// Copyright (c) 2004-2013 Sergey Lyubka // Copyright (c) 2013 Cesanta Software Limited // All rights reserved // // This library is dual-licensed: you can redistribute it and/or modify // it under the terms of the GNU General Public License version 2 as // published by the Free Software Foundation. For the terms of this // license, see . // // You are free to use this library under the terms of the GNU General // Public License, but WITHOUT ANY WARRANTY; without even the implied // warranty of MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. // See the GNU General Public License for more details. // // Alternatively, you can license this library under a commercial // license, as set out in . #if defined(_WIN32) #undef _UNICODE #define _MBCS #if !defined(_CRT_SECURE_NO_WARNINGS) #define _CRT_SECURE_NO_WARNINGS // Disable deprecation warning in VS2005 #endif #else #ifdef __linux__ #define _XOPEN_SOURCE 600 // For flockfile() on Linux #endif #if !defined(_LARGEFILE_SOURCE) #define _LARGEFILE_SOURCE // Enable 64-bit file offsets #endif #define __STDC_FORMAT_MACROS // wants this for C++ #define __STDC_LIMIT_MACROS // C++ wants that for INT64_MAX #endif #if defined (_MSC_VER) // conditional expression is constant: introduced by FD_SET(..) #pragma warning (disable : 4127) // non-constant aggregate initializer: issued due to missing C99 support #pragma warning (disable : 4204) #endif // Disable WIN32_LEAN_AND_MEAN. // This makes windows.h always include winsock2.h #ifdef WIN32_LEAN_AND_MEAN #undef WIN32_LEAN_AND_MEAN #endif #ifndef _WIN32_WCE // Some ANSI #includes are not available on Windows CE #include #include #include #include #include #endif // !_WIN32_WCE #include #include #include #include #include #include #include #include #include #if defined(_WIN32) // Windows specific #undef _WIN32_WINNT #define _WIN32_WINNT 0x0400 // To make it link in VS2005 #include #ifndef PATH_MAX #define PATH_MAX MAX_PATH #endif #ifndef _WIN32_WCE #include #include #include #else // _WIN32_WCE #define NO_CGI // WinCE has no pipes typedef long off_t; #define errno GetLastError() #define strerror(x) _ultoa(x, (char *) _alloca(sizeof(x) *3 ), 10) #endif // _WIN32_WCE #define MAKEUQUAD(lo, hi) ((uint64_t)(((uint32_t)(lo)) | \ ((uint64_t)((uint32_t)(hi))) << 32)) #define RATE_DIFF 10000000 // 100 nsecs #define EPOCH_DIFF MAKEUQUAD(0xd53e8000, 0x019db1de) #define SYS2UNIX_TIME(lo, hi) \ (time_t) ((MAKEUQUAD((lo), (hi)) - EPOCH_DIFF) / RATE_DIFF) // Visual Studio 6 does not know __func__ or __FUNCTION__ // The rest of MS compilers use __FUNCTION__, not C99 __func__ // Also use _strtoui64 on modern M$ compilers #if defined(_MSC_VER) && _MSC_VER < 1300 #define STRX(x) #x #define STR(x) STRX(x) #define __func__ __FILE__ ":" STR(__LINE__) #define strtoull(x, y, z) (unsigned __int64) _atoi64(x) #define strtoll(x, y, z) _atoi64(x) #else #define __func__ __FUNCTION__ #define strtoull(x, y, z) _strtoui64(x, y, z) #define strtoll(x, y, z) _strtoi64(x, y, z) #endif // _MSC_VER #define ERRNO GetLastError() #define NO_SOCKLEN_T #define SSL_LIB "ssleay32.dll" #define CRYPTO_LIB "libeay32.dll" #define O_NONBLOCK 0 #if !defined(EWOULDBLOCK) #define EWOULDBLOCK WSAEWOULDBLOCK #endif // !EWOULDBLOCK #define _POSIX_ #define INT64_FMT "I64d" #define WINCDECL __cdecl #define SHUT_WR 1 #define snprintf _snprintf #define vsnprintf _vsnprintf #define mg_sleep(x) Sleep(x) #define pipe(x) _pipe(x, MG_BUF_LEN, _O_BINARY) #ifndef popen #define popen(x, y) _popen(x, y) #endif #ifndef pclose #define pclose(x) _pclose(x) #endif #define close(x) _close(x) #define dlsym(x,y) GetProcAddress((HINSTANCE) (x), (y)) #define RTLD_LAZY 0 #define fseeko(x, y, z) _lseeki64(_fileno(x), (y), (z)) #define fdopen(x, y) _fdopen((x), (y)) #define write(x, y, z) _write((x), (y), (unsigned) z) #define read(x, y, z) _read((x), (y), (unsigned) z) #define flockfile(x) #define funlockfile(x) #define sleep(x) Sleep((x) * 1000) #define rmdir(x) _rmdir(x) #if !defined(va_copy) #define va_copy(x, y) x = y #endif // !va_copy MINGW #defines va_copy #if !defined(fileno) #define fileno(x) _fileno(x) #endif // !fileno MINGW #defines fileno typedef HANDLE pthread_mutex_t; typedef DWORD pthread_t; #define pid_t HANDLE // MINGW typedefs pid_t to int. Using #define here. static int pthread_mutex_lock(pthread_mutex_t *); static int pthread_mutex_unlock(pthread_mutex_t *); static void to_unicode(const char *path, wchar_t *wbuf, size_t wbuf_len); #if defined(HAVE_STDINT) #include #else typedef unsigned int uint32_t; typedef unsigned short uint16_t; typedef unsigned __int64 uint64_t; typedef __int64 int64_t; #define INT64_MAX 9223372036854775807 #endif // HAVE_STDINT // POSIX dirent interface struct dirent { char d_name[PATH_MAX]; }; typedef struct DIR { HANDLE handle; WIN32_FIND_DATAW info; struct dirent result; } DIR; struct pollfd { SOCKET fd; short events; short revents; }; #define POLLIN 1 #ifdef HAVE_POLL #define poll(x, y, z) WSAPoll((x), (y), (z)) #endif // Mark required libraries #ifdef _MSC_VER #pragma comment(lib, "Ws2_32.lib") #endif #else // UNIX specific #include #include #include #include #include #include #include #include #include #include #include #include #if !defined(NO_SSL_DL) && !defined(NO_SSL) #include #endif #include #if defined(__MACH__) #define SSL_LIB "libssl.dylib" #define CRYPTO_LIB "libcrypto.dylib" #else #if !defined(SSL_LIB) #define SSL_LIB "libssl.so" #endif #if !defined(CRYPTO_LIB) #define CRYPTO_LIB "libcrypto.so" #endif #endif #ifndef O_BINARY #define O_BINARY 0 #endif // O_BINARY #define closesocket(a) close(a) #define mg_mkdir(x, y) mkdir(x, y) #define mg_remove(x) remove(x) #define mg_sleep(x) usleep((x) * 1000) #define ERRNO errno #define INVALID_SOCKET (-1) #define INT64_FMT PRId64 typedef int SOCKET; #define WINCDECL #endif // End of Windows and UNIX specific includes #include "mongoose.h" #define MONGOOSE_VERSION "5.0" #define PASSWORDS_FILE_NAME ".htpasswd" #define CGI_ENVIRONMENT_SIZE 4096 #define MAX_CGI_ENVIR_VARS 64 #define MG_BUF_LEN 8192 #define MAX_REQUEST_SIZE 16384 #define ARRAY_SIZE(array) (sizeof(array) / sizeof(array[0])) typedef SOCKET sock_t; #ifdef DEBUG_TRACE #undef DEBUG_TRACE #define DEBUG_TRACE(x) #else #if defined(DEBUG) #define DEBUG_TRACE(x) do { \ flockfile(stdout); \ printf("*** %lu.%p.%s.%d: ", \ (unsigned long) time(NULL), (void *) pthread_self(), \ __func__, __LINE__); \ printf x; \ putchar('\n'); \ fflush(stdout); \ funlockfile(stdout); \ } while (0) #else #define DEBUG_TRACE(x) #endif // DEBUG #endif // DEBUG_TRACE // Darwin prior to 7.0 and Win32 do not have socklen_t #ifdef NO_SOCKLEN_T typedef int socklen_t; #endif // NO_SOCKLEN_T #define _DARWIN_UNLIMITED_SELECT #define IP_ADDR_STR_LEN 50 // IPv6 hex string is 46 chars #if !defined(MSG_NOSIGNAL) #define MSG_NOSIGNAL 0 #endif #if !defined(SOMAXCONN) #define SOMAXCONN 100 #endif #if !defined(PATH_MAX) #define PATH_MAX 4096 #endif // Size of the accepted socket queue #if !defined(MGSQLEN) #define MGSQLEN 20 #endif // Extra HTTP headers to send in every static file reply #if !defined(EXTRA_HTTP_HEADERS) #define EXTRA_HTTP_HEADERS "" #endif static const char *http_500_error = "Internal Server Error"; #if defined(NO_SSL_DL) #include #include #else // SSL loaded dynamically from DLL. // I put the prototypes here to be independent from OpenSSL source installation. typedef struct ssl_st SSL; typedef struct ssl_method_st SSL_METHOD; typedef struct ssl_ctx_st SSL_CTX; struct ssl_func { const char *name; // SSL function name void (*ptr)(void); // Function pointer }; #define SSL_free (* (void (*)(SSL *)) ssl_sw[0].ptr) #define SSL_accept (* (int (*)(SSL *)) ssl_sw[1].ptr) #define SSL_connect (* (int (*)(SSL *)) ssl_sw[2].ptr) #define SSL_read (* (int (*)(SSL *, void *, int)) ssl_sw[3].ptr) #define SSL_write (* (int (*)(SSL *, const void *,int)) ssl_sw[4].ptr) #define SSL_get_error (* (int (*)(SSL *, int)) ssl_sw[5].ptr) #define SSL_set_fd (* (int (*)(SSL *, SOCKET)) ssl_sw[6].ptr) #define SSL_new (* (SSL * (*)(SSL_CTX *)) ssl_sw[7].ptr) #define SSL_CTX_new (* (SSL_CTX * (*)(SSL_METHOD *)) ssl_sw[8].ptr) #define SSLv23_server_method (* (SSL_METHOD * (*)(void)) ssl_sw[9].ptr) #define SSL_library_init (* (int (*)(void)) ssl_sw[10].ptr) #define SSL_CTX_use_PrivateKey_file (* (int (*)(SSL_CTX *, \ const char *, int)) ssl_sw[11].ptr) #define SSL_CTX_use_certificate_file (* (int (*)(SSL_CTX *, \ const char *, int)) ssl_sw[12].ptr) #define SSL_CTX_set_default_passwd_cb \ (* (void (*)(SSL_CTX *, mg_event_handler_t)) ssl_sw[13].ptr) #define SSL_CTX_free (* (void (*)(SSL_CTX *)) ssl_sw[14].ptr) #define SSL_load_error_strings (* (void (*)(void)) ssl_sw[15].ptr) #define SSL_CTX_use_certificate_chain_file \ (* (int (*)(SSL_CTX *, const char *)) ssl_sw[16].ptr) #define SSLv23_client_method (* (SSL_METHOD * (*)(void)) ssl_sw[17].ptr) #define SSL_pending (* (int (*)(SSL *)) ssl_sw[18].ptr) #define SSL_CTX_set_verify (* (void (*)(SSL_CTX *, int, int)) ssl_sw[19].ptr) #define SSL_shutdown (* (int (*)(SSL *)) ssl_sw[20].ptr) #define CRYPTO_num_locks (* (int (*)(void)) crypto_sw[0].ptr) #define CRYPTO_set_locking_callback \ (* (void (*)(void (*)(int, int, const char *, int))) crypto_sw[1].ptr) #define CRYPTO_set_id_callback \ (* (void (*)(unsigned long (*)(void))) crypto_sw[2].ptr) #define ERR_get_error (* (unsigned long (*)(void)) crypto_sw[3].ptr) #define ERR_error_string (* (char * (*)(unsigned long,char *)) crypto_sw[4].ptr) #endif // NO_SSL_DL // Unified socket address. For IPv6 support, add IPv6 address structure // in the union u. union usa { struct sockaddr sa; struct sockaddr_in sin; #if defined(USE_IPV6) struct sockaddr_in6 sin6; #endif }; // Describes a string (chunk of memory). struct vec { const char *ptr; size_t len; }; struct file { int is_directory; time_t modification_time; int64_t size; // set to 1 if the content is gzipped // in which case we need a content-encoding: gzip header int gzipped; }; #define STRUCT_FILE_INITIALIZER { 0, 0, 0, 0 } // Describes listening socket, or socket which was accept()-ed by the master // thread and queued for future handling by the worker thread. struct socket { SOCKET sock; // Listening socket union usa lsa; // Local socket address union usa rsa; // Remote socket address unsigned is_ssl:1; // Is port SSL-ed unsigned ssl_redir:1; // Is port supposed to redirect everything to SSL port }; // NOTE(lsm): this enum shoulds be in sync with the config_options. enum { CGI_EXTENSIONS, CGI_ENVIRONMENT, PUT_DELETE_PASSWORDS_FILE, CGI_INTERPRETER, PROTECT_URI, AUTHENTICATION_DOMAIN, SSI_EXTENSIONS, ACCESS_LOG_FILE, ENABLE_DIRECTORY_LISTING, ERROR_LOG_FILE, GLOBAL_PASSWORDS_FILE, INDEX_FILES, ENABLE_KEEP_ALIVE, ACCESS_CONTROL_LIST, EXTRA_MIME_TYPES, LISTENING_PORTS, DOCUMENT_ROOT, SSL_CERTIFICATE, NUM_THREADS, RUN_AS_USER, REWRITE, HIDE_FILES, REQUEST_TIMEOUT, NUM_OPTIONS }; struct mg_context { volatile int stop_flag; // Should we stop event loop SSL_CTX *ssl_ctx; // SSL context char *config[NUM_OPTIONS]; // Mongoose configuration parameters mg_event_handler_t event_handler; // User-defined callback function void *user_data; // User-defined data struct socket *listening_sockets; int num_listening_sockets; int num_threads; // Number of threads sock_t ctl[2]; // Socket pair for inter-thread communication }; struct mg_connection { struct mg_request_info request_info; struct mg_event event; struct mg_context *ctx; SSL *ssl; // SSL descriptor SSL_CTX *client_ssl_ctx; // SSL context for client connections struct socket client; // Connected client time_t birth_time; // Time when request was received int64_t num_bytes_sent; // Total bytes sent to client int64_t content_len; // Content-Length header value int64_t num_bytes_read; // Bytes read from a remote socket char *buf; // Buffer for received data char *path_info; // PATH_INFO part of the URL int must_close; // 1 if connection must be closed int buf_size; // Buffer size int request_len; // Size of the request + headers in a buffer int data_len; // Total size of data in a buffer int status_code; // HTTP reply status code, e.g. 200 }; // Directory entry struct de { struct mg_connection *conn; char *file_name; struct file file; }; static FILE *mg_fopen(const char *path, const char *mode); static int mg_stat(const char *path, struct file *filep); static void send_http_error(struct mg_connection *, int, const char *, PRINTF_FORMAT_STRING(const char *fmt), ...) PRINTF_ARGS(4, 5); static void cry(struct mg_connection *conn, PRINTF_FORMAT_STRING(const char *fmt), ...) PRINTF_ARGS(2, 3); static const char *getreq(struct mg_connection *conn); #ifdef USE_LUA #include "lua_5.2.1.h" static int handle_lsp_request(struct mg_connection *, const char *, struct file *, struct lua_State *); #endif // Return fake connection structure. Used for logging, if connection // is not applicable at the moment of logging. static struct mg_connection *fc(struct mg_context *ctx) { static struct mg_connection fake_connection; fake_connection.ctx = ctx; // See https://github.com/cesanta/mongoose/issues/236 fake_connection.event.user_data = ctx->user_data; return &fake_connection; } static void sockaddr_to_string(char *buf, size_t len, const union usa *usa) { buf[0] = '\0'; #if defined(USE_IPV6) inet_ntop(usa->sa.sa_family, usa->sa.sa_family == AF_INET ? (void *) &usa->sin.sin_addr : (void *) &usa->sin6.sin6_addr, buf, len); #elif defined(_WIN32) // Only Windoze Vista (and newer) have inet_ntop() strncpy(buf, inet_ntoa(usa->sin.sin_addr), len); #else inet_ntop(usa->sa.sa_family, (void *) &usa->sin.sin_addr, buf, len); #endif } static void gmt_time_string(char *buf, size_t buf_len, time_t *t) { strftime(buf, buf_len, "%a, %d %b %Y %H:%M:%S GMT", gmtime(t)); } static void mg_strlcpy(register char *dst, register const char *src, size_t n) { for (; *src != '\0' && n > 1; n--) { *dst++ = *src++; } *dst = '\0'; } static int lowercase(const char *s) { return tolower(* (const unsigned char *) s); } static int mg_strncasecmp(const char *s1, const char *s2, size_t len) { int diff = 0; if (len > 0) do { diff = lowercase(s1++) - lowercase(s2++); } while (diff == 0 && s1[-1] != '\0' && --len > 0); return diff; } static int mg_strcasecmp(const char *s1, const char *s2) { int diff; do { diff = lowercase(s1++) - lowercase(s2++); } while (diff == 0 && s1[-1] != '\0'); return diff; } static char * mg_strndup(const char *ptr, size_t len) { char *p; if ((p = (char *) malloc(len + 1)) != NULL) { mg_strlcpy(p, ptr, len + 1); } return p; } static char * mg_strdup(const char *str) { return mg_strndup(str, strlen(str)); } static const char *mg_strcasestr(const char *big_str, const char *small_str) { int i, big_len = strlen(big_str), small_len = strlen(small_str); for (i = 0; i <= big_len - small_len; i++) { if (mg_strncasecmp(big_str + i, small_str, small_len) == 0) { return big_str + i; } } return NULL; } // Like snprintf(), but never returns negative value, or a value // that is larger than a supplied buffer. // Thanks to Adam Zeldis to pointing snprintf()-caused vulnerability // in his audit report. static int mg_vsnprintf(char *buf, size_t buflen, const char *fmt, va_list ap) { int n; if (buflen == 0) { return 0; } n = vsnprintf(buf, buflen, fmt, ap); if (n < 0) { n = 0; } else if (n >= (int) buflen) { n = (int) buflen - 1; } buf[n] = '\0'; return n; } static int mg_snprintf(char *buf, size_t buflen, PRINTF_FORMAT_STRING(const char *fmt), ...) PRINTF_ARGS(3, 4); static int mg_snprintf(char *buf, size_t buflen, const char *fmt, ...) { va_list ap; int n; va_start(ap, fmt); n = mg_vsnprintf(buf, buflen, fmt, ap); va_end(ap); return n; } // Skip the characters until one of the delimiters characters found. // 0-terminate resulting word. Skip the delimiter and following whitespaces. // Advance pointer to buffer to the next word. Return found 0-terminated word. // Delimiters can be quoted with quotechar. static char *skip_quoted(char **buf, const char *delimiters, const char *whitespace, char quotechar) { char *p, *begin_word, *end_word, *end_whitespace; begin_word = *buf; end_word = begin_word + strcspn(begin_word, delimiters); // Check for quotechar if (end_word > begin_word) { p = end_word - 1; while (*p == quotechar) { // If there is anything beyond end_word, copy it if (*end_word == '\0') { *p = '\0'; break; } else { size_t end_off = strcspn(end_word + 1, delimiters); memmove (p, end_word, end_off + 1); p += end_off; // p must correspond to end_word - 1 end_word += end_off + 1; } } for (p++; p < end_word; p++) { *p = '\0'; } } if (*end_word == '\0') { *buf = end_word; } else { end_whitespace = end_word + 1 + strspn(end_word + 1, whitespace); for (p = end_word; p < end_whitespace; p++) { *p = '\0'; } *buf = end_whitespace; } return begin_word; } // Simplified version of skip_quoted without quote char // and whitespace == delimiters static char *skip(char **buf, const char *delimiters) { return skip_quoted(buf, delimiters, delimiters, 0); } // Return HTTP header value, or NULL if not found. static const char *get_header(const struct mg_request_info *ri, const char *name) { int i; for (i = 0; i < ri->num_headers; i++) if (!mg_strcasecmp(name, ri->http_headers[i].name)) return ri->http_headers[i].value; return NULL; } const char *mg_get_header(const struct mg_connection *conn, const char *name) { return get_header(&conn->request_info, name); } // A helper function for traversing a comma separated list of values. // It returns a list pointer shifted to the next value, or NULL if the end // of the list found. // Value is stored in val vector. If value has form "x=y", then eq_val // vector is initialized to point to the "y" part, and val vector length // is adjusted to point only to "x". static const char *next_option(const char *list, struct vec *val, struct vec *eq_val) { if (list == NULL || *list == '\0') { // End of the list list = NULL; } else { val->ptr = list; if ((list = strchr(val->ptr, ',')) != NULL) { // Comma found. Store length and shift the list ptr val->len = list - val->ptr; list++; } else { // This value is the last one list = val->ptr + strlen(val->ptr); val->len = list - val->ptr; } if (eq_val != NULL) { // Value has form "x=y", adjust pointers and lengths // so that val points to "x", and eq_val points to "y". eq_val->len = 0; eq_val->ptr = (const char *) memchr(val->ptr, '=', val->len); if (eq_val->ptr != NULL) { eq_val->ptr++; // Skip over '=' character eq_val->len = val->ptr + val->len - eq_val->ptr; val->len = (eq_val->ptr - val->ptr) - 1; } } } return list; } // Perform case-insensitive match of string against pattern static int match_prefix(const char *pattern, int pattern_len, const char *str) { const char *or_str; int i, j, len, res; if ((or_str = (const char *) memchr(pattern, '|', pattern_len)) != NULL) { res = match_prefix(pattern, or_str - pattern, str); return res > 0 ? res : match_prefix(or_str + 1, (pattern + pattern_len) - (or_str + 1), str); } i = j = 0; res = -1; for (; i < pattern_len; i++, j++) { if (pattern[i] == '?' && str[j] != '\0') { continue; } else if (pattern[i] == '$') { return str[j] == '\0' ? j : -1; } else if (pattern[i] == '*') { i++; if (pattern[i] == '*') { i++; len = (int) strlen(str + j); } else { len = (int) strcspn(str + j, "/"); } if (i == pattern_len) { return j + len; } do { res = match_prefix(pattern + i, pattern_len - i, str + j + len); } while (res == -1 && len-- > 0); return res == -1 ? -1 : j + res + len; } else if (lowercase(&pattern[i]) != lowercase(&str[j])) { return -1; } } return j; } // Protect against directory disclosure attack by removing '..', // excessive '/' and '\' characters static void remove_double_dots_and_double_slashes(char *s) { char *p = s; while (*s != '\0') { *p++ = *s++; if (s[-1] == '/' || s[-1] == '\\') { // Skip all following slashes, backslashes and double-dots while (s[0] != '\0') { if (s[0] == '/' || s[0] == '\\') { s++; } else if (s[0] == '.' && s[1] == '.') { s += 2; } else { break; } } } } *p = '\0'; } void mg_url_encode(const char *src, char *dst, size_t dst_len) { static const char *dont_escape = "._-$,;~()"; static const char *hex = "0123456789abcdef"; const char *end = dst + dst_len - 1; for (; *src != '\0' && dst < end; src++, dst++) { if (isalnum(*(const unsigned char *) src) || strchr(dont_escape, * (const unsigned char *) src) != NULL) { *dst = *src; } else if (dst + 2 < end) { dst[0] = '%'; dst[1] = hex[(* (const unsigned char *) src) >> 4]; dst[2] = hex[(* (const unsigned char *) src) & 0xf]; dst += 2; } } *dst = '\0'; } int mg_url_decode(const char *src, int src_len, char *dst, int dst_len, int is_form_url_encoded) { int i, j, a, b; #define HEXTOI(x) (isdigit(x) ? x - '0' : x - 'W') for (i = j = 0; i < src_len && j < dst_len - 1; i++, j++) { if (src[i] == '%' && i < src_len - 2 && isxdigit(* (const unsigned char *) (src + i + 1)) && isxdigit(* (const unsigned char *) (src + i + 2))) { a = tolower(* (const unsigned char *) (src + i + 1)); b = tolower(* (const unsigned char *) (src + i + 2)); dst[j] = (char) ((HEXTOI(a) << 4) | HEXTOI(b)); i += 2; } else if (is_form_url_encoded && src[i] == '+') { dst[j] = ' '; } else { dst[j] = src[i]; } } dst[j] = '\0'; // Null-terminate the destination return i >= src_len ? j : -1; } // Check whether full request is buffered. Return: // -1 if request is malformed // 0 if request is not yet fully buffered // >0 actual request length, including last \r\n\r\n static int get_request_len(const char *buf, int buf_len) { int i; for (i = 0; i < buf_len; i++) { // Control characters are not allowed but >=128 is. // Abort scan as soon as one malformed character is found; // don't let subsequent \r\n\r\n win us over anyhow if (!isprint(* (const unsigned char *) &buf[i]) && buf[i] != '\r' && buf[i] != '\n' && * (const unsigned char *) &buf[i] < 128) { return -1; } else if (buf[i] == '\n' && i + 1 < buf_len && buf[i + 1] == '\n') { return i + 2; } else if (buf[i] == '\n' && i + 2 < buf_len && buf[i + 1] == '\r' && buf[i + 2] == '\n') { return i + 3; } } return 0; } int mg_get_cookie(const char *cookie_header, const char *var_name, char *dst, size_t dst_size) { const char *s, *p, *end; int name_len, len = -1; if (dst == NULL || dst_size == 0) { len = -2; } else if (var_name == NULL || (s = cookie_header) == NULL) { len = -1; dst[0] = '\0'; } else { name_len = (int) strlen(var_name); end = s + strlen(s); dst[0] = '\0'; for (; (s = mg_strcasestr(s, var_name)) != NULL; s += name_len) { if (s[name_len] == '=') { s += name_len + 1; if ((p = strchr(s, ' ')) == NULL) p = end; if (p[-1] == ';') p--; if (*s == '"' && p[-1] == '"' && p > s + 1) { s++; p--; } if ((size_t) (p - s) < dst_size) { len = p - s; mg_strlcpy(dst, s, (size_t) len + 1); } else { len = -3; } break; } } } return len; } int mg_get_var(const char *data, size_t data_len, const char *name, char *dst, size_t dst_len) { const char *p, *e, *s; size_t name_len; int len; if (dst == NULL || dst_len == 0) { len = -2; } else if (data == NULL || name == NULL || data_len == 0) { len = -1; dst[0] = '\0'; } else { name_len = strlen(name); e = data + data_len; len = -1; dst[0] = '\0'; // data is "var1=val1&var2=val2...". Find variable first for (p = data; p + name_len < e; p++) { if ((p == data || p[-1] == '&') && p[name_len] == '=' && !mg_strncasecmp(name, p, name_len)) { // Point p to variable value p += name_len + 1; // Point s to the end of the value s = (const char *) memchr(p, '&', (size_t)(e - p)); if (s == NULL) { s = e; } assert(s >= p); // Decode variable into destination buffer len = mg_url_decode(p, (size_t)(s - p), dst, dst_len, 1); // Redirect error code from -1 to -2 (destination buffer too small). if (len == -1) { len = -2; } break; } } } return len; } static const char *month_names[] = { "Jan", "Feb", "Mar", "Apr", "May", "Jun", "Jul", "Aug", "Sep", "Oct", "Nov", "Dec" }; // Convert month to the month number. Return -1 on error, or month number static int get_month_index(const char *s) { int i; for (i = 0; i < (int) ARRAY_SIZE(month_names); i++) if (!strcmp(s, month_names[i])) return i; return -1; } static int num_leap_years(int year) { return year / 4 - year / 100 + year / 400; } // Parse UTC date-time string, and return the corresponding time_t value. static time_t parse_date_string(const char *datetime) { static const unsigned short days_before_month[] = { 0, 31, 59, 90, 120, 151, 181, 212, 243, 273, 304, 334 }; char month_str[32]; int second, minute, hour, day, month, year, leap_days, days; time_t result = (time_t) 0; if (((sscanf(datetime, "%d/%3s/%d %d:%d:%d", &day, month_str, &year, &hour, &minute, &second) == 6) || (sscanf(datetime, "%d %3s %d %d:%d:%d", &day, month_str, &year, &hour, &minute, &second) == 6) || (sscanf(datetime, "%*3s, %d %3s %d %d:%d:%d", &day, month_str, &year, &hour, &minute, &second) == 6) || (sscanf(datetime, "%d-%3s-%d %d:%d:%d", &day, month_str, &year, &hour, &minute, &second) == 6)) && year > 1970 && (month = get_month_index(month_str)) != -1) { leap_days = num_leap_years(year) - num_leap_years(1970); year -= 1970; days = year * 365 + days_before_month[month] + (day - 1) + leap_days; result = days * 24 * 3600 + hour * 3600 + minute * 60 + second; } return result; } // This array must be in sync with enum in internal.h static const char *config_options[] = { "cgi_pattern", "**.cgi$|**.pl$|**.php$", "cgi_environment", NULL, "put_delete_auth_file", NULL, "cgi_interpreter", NULL, "protect_uri", NULL, "authentication_domain", "mydomain.com", "ssi_pattern", "**.shtml$|**.shtm$", "access_log_file", NULL, "enable_directory_listing", "yes", "error_log_file", NULL, "global_auth_file", NULL, "index_files", "index.html,index.htm,index.cgi,index.shtml,index.php,index.lp", "enable_keep_alive", "no", "access_control_list", NULL, "extra_mime_types", NULL, "listening_ports", "8080", "document_root", NULL, "ssl_certificate", NULL, "num_threads", "50", "run_as_user", NULL, "url_rewrite_patterns", NULL, "hide_files_patterns", NULL, "request_timeout_ms", "30000", NULL }; const char **mg_get_valid_option_names(void) { return config_options; } static int get_option_index(const char *name) { int i; for (i = 0; config_options[i * 2] != NULL; i++) { if (strcmp(config_options[i * 2], name) == 0) { return i; } } return -1; } const char *mg_get_option(const struct mg_context *ctx, const char *name) { int i; if ((i = get_option_index(name)) == -1) { return NULL; } else if (ctx->config[i] == NULL) { return ""; } else { return ctx->config[i]; } } static int is_big_endian(void) { static const int n = 1; return ((char *) &n)[0] == 0; } #ifndef HAVE_MD5 typedef struct MD5Context { uint32_t buf[4]; uint32_t bits[2]; unsigned char in[64]; } MD5_CTX; static void byteReverse(unsigned char *buf, unsigned longs) { uint32_t t; // Forrest: MD5 expect LITTLE_ENDIAN, swap if BIG_ENDIAN if (is_big_endian()) { do { t = (uint32_t) ((unsigned) buf[3] << 8 | buf[2]) << 16 | ((unsigned) buf[1] << 8 | buf[0]); * (uint32_t *) buf = t; buf += 4; } while (--longs); } } #define F1(x, y, z) (z ^ (x & (y ^ z))) #define F2(x, y, z) F1(z, x, y) #define F3(x, y, z) (x ^ y ^ z) #define F4(x, y, z) (y ^ (x | ~z)) #define MD5STEP(f, w, x, y, z, data, s) \ ( w += f(x, y, z) + data, w = w<>(32-s), w += x ) // Start MD5 accumulation. Set bit count to 0 and buffer to mysterious // initialization constants. static void MD5Init(MD5_CTX *ctx) { ctx->buf[0] = 0x67452301; ctx->buf[1] = 0xefcdab89; ctx->buf[2] = 0x98badcfe; ctx->buf[3] = 0x10325476; ctx->bits[0] = 0; ctx->bits[1] = 0; } static void MD5Transform(uint32_t buf[4], uint32_t const in[16]) { register uint32_t a, b, c, d; a = buf[0]; b = buf[1]; c = buf[2]; d = buf[3]; MD5STEP(F1, a, b, c, d, in[0] + 0xd76aa478, 7); MD5STEP(F1, d, a, b, c, in[1] + 0xe8c7b756, 12); MD5STEP(F1, c, d, a, b, in[2] + 0x242070db, 17); MD5STEP(F1, b, c, d, a, in[3] + 0xc1bdceee, 22); MD5STEP(F1, a, b, c, d, in[4] + 0xf57c0faf, 7); MD5STEP(F1, d, a, b, c, in[5] + 0x4787c62a, 12); MD5STEP(F1, c, d, a, b, in[6] + 0xa8304613, 17); MD5STEP(F1, b, c, d, a, in[7] + 0xfd469501, 22); MD5STEP(F1, a, b, c, d, in[8] + 0x698098d8, 7); MD5STEP(F1, d, a, b, c, in[9] + 0x8b44f7af, 12); MD5STEP(F1, c, d, a, b, in[10] + 0xffff5bb1, 17); MD5STEP(F1, b, c, d, a, in[11] + 0x895cd7be, 22); MD5STEP(F1, a, b, c, d, in[12] + 0x6b901122, 7); MD5STEP(F1, d, a, b, c, in[13] + 0xfd987193, 12); MD5STEP(F1, c, d, a, b, in[14] + 0xa679438e, 17); MD5STEP(F1, b, c, d, a, in[15] + 0x49b40821, 22); MD5STEP(F2, a, b, c, d, in[1] + 0xf61e2562, 5); MD5STEP(F2, d, a, b, c, in[6] + 0xc040b340, 9); MD5STEP(F2, c, d, a, b, in[11] + 0x265e5a51, 14); MD5STEP(F2, b, c, d, a, in[0] + 0xe9b6c7aa, 20); MD5STEP(F2, a, b, c, d, in[5] + 0xd62f105d, 5); MD5STEP(F2, d, a, b, c, in[10] + 0x02441453, 9); MD5STEP(F2, c, d, a, b, in[15] + 0xd8a1e681, 14); MD5STEP(F2, b, c, d, a, in[4] + 0xe7d3fbc8, 20); MD5STEP(F2, a, b, c, d, in[9] + 0x21e1cde6, 5); MD5STEP(F2, d, a, b, c, in[14] + 0xc33707d6, 9); MD5STEP(F2, c, d, a, b, in[3] + 0xf4d50d87, 14); MD5STEP(F2, b, c, d, a, in[8] + 0x455a14ed, 20); MD5STEP(F2, a, b, c, d, in[13] + 0xa9e3e905, 5); MD5STEP(F2, d, a, b, c, in[2] + 0xfcefa3f8, 9); MD5STEP(F2, c, d, a, b, in[7] + 0x676f02d9, 14); MD5STEP(F2, b, c, d, a, in[12] + 0x8d2a4c8a, 20); MD5STEP(F3, a, b, c, d, in[5] + 0xfffa3942, 4); MD5STEP(F3, d, a, b, c, in[8] + 0x8771f681, 11); MD5STEP(F3, c, d, a, b, in[11] + 0x6d9d6122, 16); MD5STEP(F3, b, c, d, a, in[14] + 0xfde5380c, 23); MD5STEP(F3, a, b, c, d, in[1] + 0xa4beea44, 4); MD5STEP(F3, d, a, b, c, in[4] + 0x4bdecfa9, 11); MD5STEP(F3, c, d, a, b, in[7] + 0xf6bb4b60, 16); MD5STEP(F3, b, c, d, a, in[10] + 0xbebfbc70, 23); MD5STEP(F3, a, b, c, d, in[13] + 0x289b7ec6, 4); MD5STEP(F3, d, a, b, c, in[0] + 0xeaa127fa, 11); MD5STEP(F3, c, d, a, b, in[3] + 0xd4ef3085, 16); MD5STEP(F3, b, c, d, a, in[6] + 0x04881d05, 23); MD5STEP(F3, a, b, c, d, in[9] + 0xd9d4d039, 4); MD5STEP(F3, d, a, b, c, in[12] + 0xe6db99e5, 11); MD5STEP(F3, c, d, a, b, in[15] + 0x1fa27cf8, 16); MD5STEP(F3, b, c, d, a, in[2] + 0xc4ac5665, 23); MD5STEP(F4, a, b, c, d, in[0] + 0xf4292244, 6); MD5STEP(F4, d, a, b, c, in[7] + 0x432aff97, 10); MD5STEP(F4, c, d, a, b, in[14] + 0xab9423a7, 15); MD5STEP(F4, b, c, d, a, in[5] + 0xfc93a039, 21); MD5STEP(F4, a, b, c, d, in[12] + 0x655b59c3, 6); MD5STEP(F4, d, a, b, c, in[3] + 0x8f0ccc92, 10); MD5STEP(F4, c, d, a, b, in[10] + 0xffeff47d, 15); MD5STEP(F4, b, c, d, a, in[1] + 0x85845dd1, 21); MD5STEP(F4, a, b, c, d, in[8] + 0x6fa87e4f, 6); MD5STEP(F4, d, a, b, c, in[15] + 0xfe2ce6e0, 10); MD5STEP(F4, c, d, a, b, in[6] + 0xa3014314, 15); MD5STEP(F4, b, c, d, a, in[13] + 0x4e0811a1, 21); MD5STEP(F4, a, b, c, d, in[4] + 0xf7537e82, 6); MD5STEP(F4, d, a, b, c, in[11] + 0xbd3af235, 10); MD5STEP(F4, c, d, a, b, in[2] + 0x2ad7d2bb, 15); MD5STEP(F4, b, c, d, a, in[9] + 0xeb86d391, 21); buf[0] += a; buf[1] += b; buf[2] += c; buf[3] += d; } static void MD5Update(MD5_CTX *ctx, unsigned char const *buf, unsigned len) { uint32_t t; t = ctx->bits[0]; if ((ctx->bits[0] = t + ((uint32_t) len << 3)) < t) ctx->bits[1]++; ctx->bits[1] += len >> 29; t = (t >> 3) & 0x3f; if (t) { unsigned char *p = (unsigned char *) ctx->in + t; t = 64 - t; if (len < t) { memcpy(p, buf, len); return; } memcpy(p, buf, t); byteReverse(ctx->in, 16); MD5Transform(ctx->buf, (uint32_t *) ctx->in); buf += t; len -= t; } while (len >= 64) { memcpy(ctx->in, buf, 64); byteReverse(ctx->in, 16); MD5Transform(ctx->buf, (uint32_t *) ctx->in); buf += 64; len -= 64; } memcpy(ctx->in, buf, len); } static void MD5Final(unsigned char digest[16], MD5_CTX *ctx) { unsigned count; unsigned char *p; uint32_t *a; count = (ctx->bits[0] >> 3) & 0x3F; p = ctx->in + count; *p++ = 0x80; count = 64 - 1 - count; if (count < 8) { memset(p, 0, count); byteReverse(ctx->in, 16); MD5Transform(ctx->buf, (uint32_t *) ctx->in); memset(ctx->in, 0, 56); } else { memset(p, 0, count - 8); } byteReverse(ctx->in, 14); a = (uint32_t *)ctx->in; a[14] = ctx->bits[0]; a[15] = ctx->bits[1]; MD5Transform(ctx->buf, (uint32_t *) ctx->in); byteReverse((unsigned char *) ctx->buf, 4); memcpy(digest, ctx->buf, 16); memset((char *) ctx, 0, sizeof(*ctx)); } #endif // !HAVE_MD5 // Stringify binary data. Output buffer must be twice as big as input, // because each byte takes 2 bytes in string representation static void bin2str(char *to, const unsigned char *p, size_t len) { static const char *hex = "0123456789abcdef"; for (; len--; p++) { *to++ = hex[p[0] >> 4]; *to++ = hex[p[0] & 0x0f]; } *to = '\0'; } // Return stringified MD5 hash for list of strings. Buffer must be 33 bytes. char *mg_md5(char buf[33], ...) { unsigned char hash[16]; const char *p; va_list ap; MD5_CTX ctx; MD5Init(&ctx); va_start(ap, buf); while ((p = va_arg(ap, const char *)) != NULL) { MD5Update(&ctx, (const unsigned char *) p, (unsigned) strlen(p)); } va_end(ap); MD5Final(hash, &ctx); bin2str(buf, hash, sizeof(hash)); return buf; } // Check the user's password, return 1 if OK static int check_password(const char *method, const char *ha1, const char *uri, const char *nonce, const char *nc, const char *cnonce, const char *qop, const char *response) { char ha2[32 + 1], expected_response[32 + 1]; // Some of the parameters may be NULL if (method == NULL || nonce == NULL || nc == NULL || cnonce == NULL || qop == NULL || response == NULL) { return 0; } // NOTE(lsm): due to a bug in MSIE, we do not compare the URI // TODO(lsm): check for authentication timeout if (// strcmp(dig->uri, c->ouri) != 0 || strlen(response) != 32 // || now - strtoul(dig->nonce, NULL, 10) > 3600 ) { return 0; } mg_md5(ha2, method, ":", uri, NULL); mg_md5(expected_response, ha1, ":", nonce, ":", nc, ":", cnonce, ":", qop, ":", ha2, NULL); return mg_strcasecmp(response, expected_response) == 0; } // Use the global passwords file, if specified by auth_gpass option, // or search for .htpasswd in the requested directory. static FILE *open_auth_file(struct mg_connection *conn, const char *path) { char name[PATH_MAX]; const char *p, *e, *gpass = conn->ctx->config[GLOBAL_PASSWORDS_FILE]; struct file file = STRUCT_FILE_INITIALIZER; FILE *fp = NULL; if (gpass != NULL) { // Use global passwords file fp = mg_fopen(gpass, "r"); // Important: using local struct file to test path for is_directory flag. // If filep is used, mg_stat() makes it appear as if auth file was opened. } else if (mg_stat(path, &file) && file.is_directory) { mg_snprintf(name, sizeof(name), "%s%c%s", path, '/', PASSWORDS_FILE_NAME); fp = mg_fopen(name, "r"); } else { // Try to find .htpasswd in requested directory. for (p = path, e = p + strlen(p) - 1; e > p; e--) if (e[0] == '/') break; mg_snprintf(name, sizeof(name), "%.*s%c%s", (int) (e - p), p, '/', PASSWORDS_FILE_NAME); fp = mg_fopen(name, "r"); } return fp; } // Parsed Authorization header struct ah { char *user, *uri, *cnonce, *response, *qop, *nc, *nonce; }; // Return 1 on success. Always initializes the ah structure. static int parse_auth_header(struct mg_connection *conn, char *buf, size_t buf_size, struct ah *ah) { char *name, *value, *s; const char *auth_header; (void) memset(ah, 0, sizeof(*ah)); if ((auth_header = mg_get_header(conn, "Authorization")) == NULL || mg_strncasecmp(auth_header, "Digest ", 7) != 0) { return 0; } // Make modifiable copy of the auth header (void) mg_strlcpy(buf, auth_header + 7, buf_size); s = buf; // Parse authorization header for (;;) { // Gobble initial spaces while (isspace(* (unsigned char *) s)) { s++; } name = skip_quoted(&s, "=", " ", 0); // Value is either quote-delimited, or ends at first comma or space. if (s[0] == '\"') { s++; value = skip_quoted(&s, "\"", " ", '\\'); if (s[0] == ',') { s++; } } else { value = skip_quoted(&s, ", ", " ", 0); // IE uses commas, FF uses spaces } if (*name == '\0') { break; } if (!strcmp(name, "username")) { ah->user = value; } else if (!strcmp(name, "cnonce")) { ah->cnonce = value; } else if (!strcmp(name, "response")) { ah->response = value; } else if (!strcmp(name, "uri")) { ah->uri = value; } else if (!strcmp(name, "qop")) { ah->qop = value; } else if (!strcmp(name, "nc")) { ah->nc = value; } else if (!strcmp(name, "nonce")) { ah->nonce = value; } } // CGI needs it as REMOTE_USER if (ah->user != NULL) { conn->request_info.remote_user = mg_strdup(ah->user); } else { return 0; } return 1; } // Authorize against the opened passwords file. Return 1 if authorized. static int authorize(struct mg_connection *conn, FILE *fp) { struct ah ah; char line[256], f_user[256], ha1[256], f_domain[256], buf[MG_BUF_LEN]; if (!parse_auth_header(conn, buf, sizeof(buf), &ah)) { return 0; } // Loop over passwords file while (fgets(line, sizeof(line), fp) != NULL) { if (sscanf(line, "%[^:]:%[^:]:%s", f_user, f_domain, ha1) != 3) { continue; } if (!strcmp(ah.user, f_user) && !strcmp(conn->ctx->config[AUTHENTICATION_DOMAIN], f_domain)) return check_password(conn->request_info.request_method, ha1, ah.uri, ah.nonce, ah.nc, ah.cnonce, ah.qop, ah.response); } return 0; } // Return 1 if request is authorised, 0 otherwise. static int check_authorization(struct mg_connection *conn, const char *path) { char fname[PATH_MAX]; struct vec uri_vec, filename_vec; const char *list; FILE *fp = NULL; int authorized = 1; list = conn->ctx->config[PROTECT_URI]; while ((list = next_option(list, &uri_vec, &filename_vec)) != NULL) { if (!memcmp(conn->request_info.uri, uri_vec.ptr, uri_vec.len)) { mg_snprintf(fname, sizeof(fname), "%.*s", (int) filename_vec.len, filename_vec.ptr); fp = mg_fopen(fname, "r"); break; } } if (fp == NULL) { fp = open_auth_file(conn, path); } if (fp != NULL) { authorized = authorize(conn, fp); fclose(fp); } return authorized; } static void send_authorization_request(struct mg_connection *conn) { conn->status_code = 401; mg_printf(conn, "HTTP/1.1 401 Unauthorized\r\n" "Content-Length: 0\r\n" "WWW-Authenticate: Digest qop=\"auth\", " "realm=\"%s\", nonce=\"%lu\"\r\n\r\n", conn->ctx->config[AUTHENTICATION_DOMAIN], (unsigned long) time(NULL)); } static int is_authorized_for_put(struct mg_connection *conn) { const char *passfile = conn->ctx->config[PUT_DELETE_PASSWORDS_FILE]; FILE *fp; int ret = 0; if (passfile != NULL && (fp = mg_fopen(passfile, "r")) != NULL) { ret = authorize(conn, fp); fclose(fp); } return ret; } int mg_modify_passwords_file(const char *fname, const char *domain, const char *user, const char *pass) { int found; char line[512], u[512], d[512], ha1[33], tmp[PATH_MAX]; FILE *fp, *fp2; found = 0; fp = fp2 = NULL; // Regard empty password as no password - remove user record. if (pass != NULL && pass[0] == '\0') { pass = NULL; } (void) snprintf(tmp, sizeof(tmp), "%s.tmp", fname); // Create the file if does not exist if ((fp = fopen(fname, "a+")) != NULL) { fclose(fp); } // Open the given file and temporary file if ((fp = fopen(fname, "r")) == NULL) { return 0; } else if ((fp2 = fopen(tmp, "w+")) == NULL) { fclose(fp); return 0; } // Copy the stuff to temporary file while (fgets(line, sizeof(line), fp) != NULL) { if (sscanf(line, "%[^:]:%[^:]:%*s", u, d) != 2) { continue; } if (!strcmp(u, user) && !strcmp(d, domain)) { found++; if (pass != NULL) { mg_md5(ha1, user, ":", domain, ":", pass, NULL); fprintf(fp2, "%s:%s:%s\n", user, domain, ha1); } } else { fprintf(fp2, "%s", line); } } // If new user, just add it if (!found && pass != NULL) { mg_md5(ha1, user, ":", domain, ":", pass, NULL); fprintf(fp2, "%s:%s:%s\n", user, domain, ha1); } // Close files fclose(fp); fclose(fp2); // Put the temp file in place of real file remove(fname); rename(tmp, fname); return 1; } #if defined(_WIN32) static pthread_t pthread_self(void) { return GetCurrentThreadId(); } static int pthread_mutex_init(pthread_mutex_t *mutex, void *unused) { (void) unused; *mutex = CreateMutex(NULL, FALSE, NULL); return *mutex == NULL ? -1 : 0; } static int pthread_mutex_destroy(pthread_mutex_t *mutex) { return CloseHandle(*mutex) == 0 ? -1 : 0; } static int pthread_mutex_lock(pthread_mutex_t *mutex) { return WaitForSingleObject(*mutex, INFINITE) == WAIT_OBJECT_0? 0 : -1; } static int pthread_mutex_unlock(pthread_mutex_t *mutex) { return ReleaseMutex(*mutex) == 0 ? -1 : 0; } // For Windows, change all slashes to backslashes in path names. static void change_slashes_to_backslashes(char *path) { int i; for (i = 0; path[i] != '\0'; i++) { if (path[i] == '/') path[i] = '\\'; // i > 0 check is to preserve UNC paths, like \\server\file.txt if (path[i] == '\\' && i > 0) while (path[i + 1] == '\\' || path[i + 1] == '/') (void) memmove(path + i + 1, path + i + 2, strlen(path + i + 1)); } } // Encode 'path' which is assumed UTF-8 string, into UNICODE string. // wbuf and wbuf_len is a target buffer and its length. static void to_unicode(const char *path, wchar_t *wbuf, size_t wbuf_len) { char buf[PATH_MAX * 2], buf2[PATH_MAX * 2]; mg_strlcpy(buf, path, sizeof(buf)); change_slashes_to_backslashes(buf); // Convert to Unicode and back. If doubly-converted string does not // match the original, something is fishy, reject. memset(wbuf, 0, wbuf_len * sizeof(wchar_t)); MultiByteToWideChar(CP_UTF8, 0, buf, -1, wbuf, (int) wbuf_len); WideCharToMultiByte(CP_UTF8, 0, wbuf, (int) wbuf_len, buf2, sizeof(buf2), NULL, NULL); if (strcmp(buf, buf2) != 0) { wbuf[0] = L'\0'; } } #if defined(_WIN32_WCE) static time_t time(time_t *ptime) { time_t t; SYSTEMTIME st; FILETIME ft; GetSystemTime(&st); SystemTimeToFileTime(&st, &ft); t = SYS2UNIX_TIME(ft.dwLowDateTime, ft.dwHighDateTime); if (ptime != NULL) { *ptime = t; } return t; } static struct tm *localtime(const time_t *ptime, struct tm *ptm) { int64_t t = ((int64_t) *ptime) * RATE_DIFF + EPOCH_DIFF; FILETIME ft, lft; SYSTEMTIME st; TIME_ZONE_INFORMATION tzinfo; if (ptm == NULL) { return NULL; } * (int64_t *) &ft = t; FileTimeToLocalFileTime(&ft, &lft); FileTimeToSystemTime(&lft, &st); ptm->tm_year = st.wYear - 1900; ptm->tm_mon = st.wMonth - 1; ptm->tm_wday = st.wDayOfWeek; ptm->tm_mday = st.wDay; ptm->tm_hour = st.wHour; ptm->tm_min = st.wMinute; ptm->tm_sec = st.wSecond; ptm->tm_yday = 0; // hope nobody uses this ptm->tm_isdst = GetTimeZoneInformation(&tzinfo) == TIME_ZONE_ID_DAYLIGHT ? 1 : 0; return ptm; } static struct tm *gmtime(const time_t *ptime, struct tm *ptm) { // FIXME(lsm): fix this. return localtime(ptime, ptm); } static size_t strftime(char *dst, size_t dst_size, const char *fmt, const struct tm *tm) { (void) snprintf(dst, dst_size, "implement strftime() for WinCE"); return 0; } #endif // Windows happily opens files with some garbage at the end of file name. // For example, fopen("a.cgi ", "r") on Windows successfully opens // "a.cgi", despite one would expect an error back. // This function returns non-0 if path ends with some garbage. static int path_cannot_disclose_cgi(const char *path) { static const char *allowed_last_characters = "_-"; int last = path[strlen(path) - 1]; return isalnum(last) || strchr(allowed_last_characters, last) != NULL; } static int mg_stat(const char *path, struct file *filep) { wchar_t wbuf[PATH_MAX] = L"\\\\?\\"; WIN32_FILE_ATTRIBUTE_DATA info; filep->modification_time = 0; to_unicode(path, wbuf + 4, ARRAY_SIZE(wbuf) - 4); if (GetFileAttributesExW(wbuf, GetFileExInfoStandard, &info) != 0) { filep->size = MAKEUQUAD(info.nFileSizeLow, info.nFileSizeHigh); filep->modification_time = SYS2UNIX_TIME( info.ftLastWriteTime.dwLowDateTime, info.ftLastWriteTime.dwHighDateTime); filep->is_directory = info.dwFileAttributes & FILE_ATTRIBUTE_DIRECTORY; // If file name is fishy, reset the file structure and return error. // Note it is important to reset, not just return the error, cause // functions like is_file_opened() check the struct. if (!filep->is_directory && !path_cannot_disclose_cgi(path)) { memset(filep, 0, sizeof(*filep)); } } return filep->modification_time != 0; } static int mg_remove(const char *path) { wchar_t wbuf[PATH_MAX]; to_unicode(path, wbuf, ARRAY_SIZE(wbuf)); return DeleteFileW(wbuf) ? 0 : -1; } static int mg_mkdir(const char *path, int mode) { char buf[PATH_MAX]; wchar_t wbuf[PATH_MAX]; (void) mode; mg_strlcpy(buf, path, sizeof(buf)); change_slashes_to_backslashes(buf); (void) MultiByteToWideChar(CP_UTF8, 0, buf, -1, wbuf, ARRAY_SIZE(wbuf)); return CreateDirectoryW(wbuf, NULL) ? 0 : -1; } // Implementation of POSIX opendir/closedir/readdir for Windows. static DIR * opendir(const char *name) { DIR *dir = NULL; wchar_t wpath[PATH_MAX]; DWORD attrs; if (name == NULL) { SetLastError(ERROR_BAD_ARGUMENTS); } else if ((dir = (DIR *) malloc(sizeof(*dir))) == NULL) { SetLastError(ERROR_NOT_ENOUGH_MEMORY); } else { to_unicode(name, wpath, ARRAY_SIZE(wpath)); attrs = GetFileAttributesW(wpath); if (attrs != 0xFFFFFFFF && ((attrs & FILE_ATTRIBUTE_DIRECTORY) == FILE_ATTRIBUTE_DIRECTORY)) { (void) wcscat(wpath, L"\\*"); dir->handle = FindFirstFileW(wpath, &dir->info); dir->result.d_name[0] = '\0'; } else { free(dir); dir = NULL; } } return dir; } static int closedir(DIR *dir) { int result = 0; if (dir != NULL) { if (dir->handle != INVALID_HANDLE_VALUE) result = FindClose(dir->handle) ? 0 : -1; free(dir); } else { result = -1; SetLastError(ERROR_BAD_ARGUMENTS); } return result; } static struct dirent *readdir(DIR *dir) { struct dirent *result = 0; if (dir) { if (dir->handle != INVALID_HANDLE_VALUE) { result = &dir->result; (void) WideCharToMultiByte(CP_UTF8, 0, dir->info.cFileName, -1, result->d_name, sizeof(result->d_name), NULL, NULL); if (!FindNextFileW(dir->handle, &dir->info)) { (void) FindClose(dir->handle); dir->handle = INVALID_HANDLE_VALUE; } } else { SetLastError(ERROR_FILE_NOT_FOUND); } } else { SetLastError(ERROR_BAD_ARGUMENTS); } return result; } #ifndef HAVE_POLL static int poll(struct pollfd *pfd, int n, int milliseconds) { struct timeval tv; fd_set set; int i, result; SOCKET maxfd = 0; tv.tv_sec = milliseconds / 1000; tv.tv_usec = (milliseconds % 1000) * 1000; FD_ZERO(&set); for (i = 0; i < n; i++) { FD_SET((SOCKET) pfd[i].fd, &set); pfd[i].revents = 0; if (pfd[i].fd > maxfd) { maxfd = pfd[i].fd; } } if ((result = select(maxfd + 1, &set, NULL, NULL, &tv)) > 0) { for (i = 0; i < n; i++) { if (FD_ISSET(pfd[i].fd, &set)) { pfd[i].revents = POLLIN; } } } return result; } #endif // HAVE_POLL static void set_close_on_exec(SOCKET sock) { (void) SetHandleInformation((HANDLE) sock, HANDLE_FLAG_INHERIT, 0); } int mg_start_thread(mg_thread_func_t f, void *p) { return (long)_beginthread((void (__cdecl *)(void *)) f, 0, p) == -1L ? -1 : 0; } static HANDLE dlopen(const char *dll_name, int flags) { wchar_t wbuf[PATH_MAX]; (void) flags; to_unicode(dll_name, wbuf, ARRAY_SIZE(wbuf)); return LoadLibraryW(wbuf); } #if !defined(NO_CGI) #define SIGKILL 0 static int kill(pid_t pid, int sig_num) { (void) TerminateProcess(pid, sig_num); (void) CloseHandle(pid); return 0; } static void trim_trailing_whitespaces(char *s) { char *e = s + strlen(s) - 1; while (e > s && isspace(* (unsigned char *) e)) { *e-- = '\0'; } } static pid_t spawn_process(struct mg_connection *conn, const char *prog, char *envblk, char *envp[], int fdin, int fdout, const char *dir) { HANDLE me; char *interp, full_interp[PATH_MAX], full_dir[PATH_MAX], cmdline[PATH_MAX], buf[PATH_MAX]; FILE *fp; STARTUPINFOA si; PROCESS_INFORMATION pi = { 0 }; (void) envp; memset(&si, 0, sizeof(si)); si.cb = sizeof(si); // TODO(lsm): redirect CGI errors to the error log file si.dwFlags = STARTF_USESTDHANDLES | STARTF_USESHOWWINDOW; si.wShowWindow = SW_HIDE; me = GetCurrentProcess(); DuplicateHandle(me, (HANDLE) _get_osfhandle(fdin), me, &si.hStdInput, 0, TRUE, DUPLICATE_SAME_ACCESS); DuplicateHandle(me, (HANDLE) _get_osfhandle(fdout), me, &si.hStdOutput, 0, TRUE, DUPLICATE_SAME_ACCESS); // If CGI file is a script, try to read the interpreter line interp = conn->ctx->config[CGI_INTERPRETER]; if (interp == NULL) { buf[0] = buf[1] = '\0'; // Read the first line of the script into the buffer snprintf(cmdline, sizeof(cmdline), "%s%c%s", dir, '/', prog); if ((fp = mg_fopen(cmdline, "r")) != NULL) { fgets(buf, sizeof(buf), fp); fclose(fp); buf[sizeof(buf) - 1] = '\0'; } if (buf[0] == '#' && buf[1] == '!') { trim_trailing_whitespaces(buf + 2); } else { buf[2] = '\0'; } interp = buf + 2; } if (interp[0] != '\0') { GetFullPathNameA(interp, sizeof(full_interp), full_interp, NULL); interp = full_interp; } GetFullPathNameA(dir, sizeof(full_dir), full_dir, NULL); mg_snprintf(cmdline, sizeof(cmdline), "%s%s\"%s\\%s\"", interp, interp[0] == '\0' ? "" : " ", full_dir, prog); DEBUG_TRACE(("Running [%s]", cmdline)); if (CreateProcessA(NULL, cmdline, NULL, NULL, TRUE, CREATE_NEW_PROCESS_GROUP, envblk, NULL, &si, &pi) == 0) { cry(conn, "%s: CreateProcess(%s): %ld", __func__, cmdline, ERRNO); pi.hProcess = (pid_t) -1; } (void) CloseHandle(si.hStdOutput); (void) CloseHandle(si.hStdInput); (void) CloseHandle(pi.hThread); return (pid_t) pi.hProcess; } #endif // !NO_CGI static int set_non_blocking_mode(SOCKET sock) { unsigned long on = 1; return ioctlsocket(sock, FIONBIO, &on); } #endif #if !defined(_WIN32) static int mg_stat(const char *path, struct file *filep) { struct stat st; filep->modification_time = (time_t) 0; if (stat(path, &st) == 0) { filep->size = st.st_size; filep->modification_time = st.st_mtime; filep->is_directory = S_ISDIR(st.st_mode); // See https://github.com/cesanta/mongoose/issues/109 // Some filesystems report modification time as 0. Artificially // bump it up to mark mg_stat() success. if (filep->modification_time == (time_t) 0) { filep->modification_time = (time_t) 1; } } return filep->modification_time != (time_t) 0; } static void set_close_on_exec(int fd) { fcntl(fd, F_SETFD, FD_CLOEXEC); } int mg_start_thread(mg_thread_func_t func, void *param) { pthread_t thread_id; pthread_attr_t attr; int result; (void) pthread_attr_init(&attr); (void) pthread_attr_setdetachstate(&attr, PTHREAD_CREATE_DETACHED); #if USE_STACK_SIZE > 1 // Compile-time option to control stack size, e.g. -DUSE_STACK_SIZE=16384 (void) pthread_attr_setstacksize(&attr, USE_STACK_SIZE); #endif result = pthread_create(&thread_id, &attr, func, param); pthread_attr_destroy(&attr); return result; } #ifndef NO_CGI static pid_t spawn_process(struct mg_connection *conn, const char *prog, char *envblk, char *envp[], int fdin, int fdout, const char *dir) { pid_t pid; const char *interp; (void) envblk; if ((pid = fork()) == -1) { // Parent send_http_error(conn, 500, http_500_error, "fork(): %s", strerror(ERRNO)); } else if (pid == 0) { // Child if (chdir(dir) != 0) { cry(conn, "%s: chdir(%s): %s", __func__, dir, strerror(ERRNO)); } else if (dup2(fdin, 0) == -1) { cry(conn, "%s: dup2(%d, 0): %s", __func__, fdin, strerror(ERRNO)); } else if (dup2(fdout, 1) == -1) { cry(conn, "%s: dup2(%d, 1): %s", __func__, fdout, strerror(ERRNO)); } else { // Not redirecting stderr to stdout, to avoid output being littered // with the error messages. (void) close(fdin); (void) close(fdout); // After exec, all signal handlers are restored to their default values, // with one exception of SIGCHLD. According to POSIX.1-2001 and Linux's // implementation, SIGCHLD's handler will leave unchanged after exec // if it was set to be ignored. Restore it to default action. signal(SIGCHLD, SIG_DFL); interp = conn->ctx->config[CGI_INTERPRETER]; if (interp == NULL) { (void) execle(prog, prog, NULL, envp); cry(conn, "%s: execle(%s): %s", __func__, prog, strerror(ERRNO)); } else { (void) execle(interp, interp, prog, NULL, envp); cry(conn, "%s: execle(%s %s): %s", __func__, interp, prog, strerror(ERRNO)); } } exit(EXIT_FAILURE); } return pid; } #endif // !NO_CGI static int set_non_blocking_mode(SOCKET sock) { int flags; flags = fcntl(sock, F_GETFL, 0); (void) fcntl(sock, F_SETFL, flags | O_NONBLOCK); return 0; } #endif // _WIN32 // Print message to buffer. If buffer is large enough to hold the message, // return buffer. If buffer is to small, allocate large enough buffer on heap, // and return allocated buffer. static int alloc_vprintf(char **buf, size_t size, const char *fmt, va_list ap) { va_list ap_copy; int len; // Windows is not standard-compliant, and vsnprintf() returns -1 if // buffer is too small. Also, older versions of msvcrt.dll do not have // _vscprintf(). However, if size is 0, vsnprintf() behaves correctly. // Therefore, we make two passes: on first pass, get required message length. // On second pass, actually print the message. va_copy(ap_copy, ap); len = vsnprintf(NULL, 0, fmt, ap_copy); if (len > (int) size && (size = len + 1) > 0 && (*buf = (char *) malloc(size)) == NULL) { len = -1; // Allocation failed, mark failure } else { va_copy(ap_copy, ap); vsnprintf(*buf, size, fmt, ap_copy); } return len; } int mg_vprintf(struct mg_connection *conn, const char *fmt, va_list ap) { char mem[MG_BUF_LEN], *buf = mem; int len; if ((len = alloc_vprintf(&buf, sizeof(mem), fmt, ap)) > 0) { len = mg_write(conn, buf, (size_t) len); } if (buf != mem && buf != NULL) { free(buf); } return len; } int mg_printf(struct mg_connection *conn, const char *fmt, ...) { va_list ap; va_start(ap, fmt); return mg_vprintf(conn, fmt, ap); } static int mg_chunked_printf(struct mg_connection *conn, const char *fmt, ...) { char mem[MG_BUF_LEN], *buf = mem; int len; va_list ap; va_start(ap, fmt); if ((len = alloc_vprintf(&buf, sizeof(mem), fmt, ap)) > 0) { len = mg_printf(conn, "%X\r\n%s\r\n", len, buf); } if (buf != mem && buf != NULL) { free(buf); } return len; } #if !defined(NO_SSL) // set_ssl_option() function updates this array. // It loads SSL library dynamically and changes NULLs to the actual addresses // of respective functions. The macros above (like SSL_connect()) are really // just calling these functions indirectly via the pointer. static struct ssl_func ssl_sw[] = { {"SSL_free", NULL}, {"SSL_accept", NULL}, {"SSL_connect", NULL}, {"SSL_read", NULL}, {"SSL_write", NULL}, {"SSL_get_error", NULL}, {"SSL_set_fd", NULL}, {"SSL_new", NULL}, {"SSL_CTX_new", NULL}, {"SSLv23_server_method", NULL}, {"SSL_library_init", NULL}, {"SSL_CTX_use_PrivateKey_file", NULL}, {"SSL_CTX_use_certificate_file",NULL}, {"SSL_CTX_set_default_passwd_cb",NULL}, {"SSL_CTX_free", NULL}, {"SSL_load_error_strings", NULL}, {"SSL_CTX_use_certificate_chain_file", NULL}, {"SSLv23_client_method", NULL}, {"SSL_pending", NULL}, {"SSL_CTX_set_verify", NULL}, {"SSL_shutdown", NULL}, {NULL, NULL} }; // Similar array as ssl_sw. These functions could be located in different lib. static struct ssl_func crypto_sw[] = { {"CRYPTO_num_locks", NULL}, {"CRYPTO_set_locking_callback", NULL}, {"CRYPTO_set_id_callback", NULL}, {"ERR_get_error", NULL}, {"ERR_error_string", NULL}, {NULL, NULL} }; static pthread_mutex_t *ssl_mutexes; static int sslize(struct mg_connection *conn, SSL_CTX *s, int (*func)(SSL *)) { return (conn->ssl = SSL_new(s)) != NULL && SSL_set_fd(conn->ssl, conn->client.sock) == 1 && func(conn->ssl) == 1; } // Return OpenSSL error message static const char *ssl_error(void) { unsigned long err; err = ERR_get_error(); return err == 0 ? "" : ERR_error_string(err, NULL); } static void ssl_locking_callback(int mode, int mutex_num, const char *file, int line) { (void) line; (void) file; if (mode & 1) { // 1 is CRYPTO_LOCK (void) pthread_mutex_lock(&ssl_mutexes[mutex_num]); } else { (void) pthread_mutex_unlock(&ssl_mutexes[mutex_num]); } } static unsigned long ssl_id_callback(void) { return (unsigned long) pthread_self(); } #if !defined(NO_SSL_DL) static int load_dll(struct mg_context *ctx, const char *dll_name, struct ssl_func *sw) { union {void *p; void (*fp)(void);} u; void *dll_handle; struct ssl_func *fp; if ((dll_handle = dlopen(dll_name, RTLD_LAZY)) == NULL) { cry(fc(ctx), "%s: cannot load %s", __func__, dll_name); return 0; } for (fp = sw; fp->name != NULL; fp++) { #ifdef _WIN32 // GetProcAddress() returns pointer to function u.fp = (void (*)(void)) dlsym(dll_handle, fp->name); #else // dlsym() on UNIX returns void *. ISO C forbids casts of data pointers to // function pointers. We need to use a union to make a cast. u.p = dlsym(dll_handle, fp->name); #endif // _WIN32 if (u.fp == NULL) { cry(fc(ctx), "%s: %s: cannot find %s", __func__, dll_name, fp->name); return 0; } else { fp->ptr = u.fp; } } return 1; } #endif // NO_SSL_DL // Dynamically load SSL library. Set up ctx->ssl_ctx pointer. static int set_ssl_option(struct mg_context *ctx) { int i, size; const char *pem; // If PEM file is not specified and the init_ssl callback // is not specified, skip SSL initialization. if ((pem = ctx->config[SSL_CERTIFICATE]) == NULL) { // MG_INIT_SSL // ctx->callbacks.init_ssl == NULL) { return 1; } #if !defined(NO_SSL_DL) if (!load_dll(ctx, SSL_LIB, ssl_sw) || !load_dll(ctx, CRYPTO_LIB, crypto_sw)) { return 0; } #endif // NO_SSL_DL // Initialize SSL library SSL_library_init(); SSL_load_error_strings(); if ((ctx->ssl_ctx = SSL_CTX_new(SSLv23_server_method())) == NULL) { cry(fc(ctx), "SSL_CTX_new (server) error: %s", ssl_error()); return 0; } // If user callback returned non-NULL, that means that user callback has // set up certificate itself. In this case, skip sertificate setting. // MG_INIT_SSL if (SSL_CTX_use_certificate_file(ctx->ssl_ctx, pem, 1) == 0 || SSL_CTX_use_PrivateKey_file(ctx->ssl_ctx, pem, 1) == 0) { cry(fc(ctx), "%s: cannot open %s: %s", __func__, pem, ssl_error()); return 0; } if (pem != NULL) { (void) SSL_CTX_use_certificate_chain_file(ctx->ssl_ctx, pem); } // Initialize locking callbacks, needed for thread safety. // http://www.openssl.org/support/faq.html#PROG1 size = sizeof(pthread_mutex_t) * CRYPTO_num_locks(); if ((ssl_mutexes = (pthread_mutex_t *) malloc((size_t)size)) == NULL) { cry(fc(ctx), "%s: cannot allocate mutexes: %s", __func__, ssl_error()); return 0; } for (i = 0; i < CRYPTO_num_locks(); i++) { pthread_mutex_init(&ssl_mutexes[i], NULL); } CRYPTO_set_locking_callback(&ssl_locking_callback); CRYPTO_set_id_callback(&ssl_id_callback); return 1; } static void uninitialize_ssl(struct mg_context *ctx) { int i; if (ctx->ssl_ctx != NULL) { CRYPTO_set_locking_callback(NULL); for (i = 0; i < CRYPTO_num_locks(); i++) { pthread_mutex_destroy(&ssl_mutexes[i]); } CRYPTO_set_locking_callback(NULL); CRYPTO_set_id_callback(NULL); } } #endif // !NO_SSL static SOCKET conn2(const char *host, int port, int use_ssl, char *ebuf, size_t ebuf_len) { struct sockaddr_in sin; struct hostent *he = NULL; SOCKET sock = INVALID_SOCKET; (void) use_ssl; // Prevent warning for -DNO_SSL case if (host == NULL) { snprintf(ebuf, ebuf_len, "%s", "NULL host"); #ifndef NO_SSL } else if (use_ssl && SSLv23_client_method == NULL) { snprintf(ebuf, ebuf_len, "%s", "SSL is not initialized"); // TODO(lsm): use something threadsafe instead of gethostbyname() #endif } else if ((he = gethostbyname(host)) == NULL) { snprintf(ebuf, ebuf_len, "gethostbyname(%s): %s", host, strerror(ERRNO)); } else if ((sock = socket(PF_INET, SOCK_STREAM, 0)) == INVALID_SOCKET) { snprintf(ebuf, ebuf_len, "socket(): %s", strerror(ERRNO)); } else { set_close_on_exec(sock); sin.sin_family = AF_INET; sin.sin_port = htons((uint16_t) port); sin.sin_addr = * (struct in_addr *) he->h_addr_list[0]; if (connect(sock, (struct sockaddr *) &sin, sizeof(sin)) != 0) { snprintf(ebuf, ebuf_len, "connect(%s:%d): %s", host, port, strerror(ERRNO)); closesocket(sock); sock = INVALID_SOCKET; } } return sock; } struct mg_connection *mg_connect(const char *host, int port, int use_ssl, char *ebuf, size_t ebuf_len) { static struct mg_context fake_ctx; struct mg_connection *conn = NULL; SOCKET sock; if ((sock = conn2(host, port, use_ssl, ebuf, ebuf_len)) == INVALID_SOCKET) { } else if ((conn = (struct mg_connection *) calloc(1, sizeof(*conn) + MAX_REQUEST_SIZE)) == NULL) { snprintf(ebuf, ebuf_len, "calloc(): %s", strerror(ERRNO)); closesocket(sock); #ifndef NO_SSL } else if (use_ssl && (conn->client_ssl_ctx = SSL_CTX_new(SSLv23_client_method())) == NULL) { snprintf(ebuf, ebuf_len, "SSL_CTX_new error"); closesocket(sock); free(conn); conn = NULL; #endif // NO_SSL } else { socklen_t len = sizeof(struct sockaddr); conn->buf_size = MAX_REQUEST_SIZE; conn->buf = (char *) (conn + 1); conn->ctx = &fake_ctx; conn->client.sock = sock; getsockname(sock, &conn->client.rsa.sa, &len); conn->client.is_ssl = use_ssl; #ifndef NO_SSL if (use_ssl) { // SSL_CTX_set_verify call is needed to switch off server certificate // checking, which is off by default in OpenSSL and on in yaSSL. SSL_CTX_set_verify(conn->client_ssl_ctx, 0, 0); sslize(conn, conn->client_ssl_ctx, SSL_connect); } #endif } return conn; } struct mg_connection *mg_download(const char *host, int port, int use_ssl, char *ebuf, size_t ebuf_len, const char *fmt, ...) { struct mg_connection *conn; const char *msg = NULL; va_list ap; va_start(ap, fmt); if ((conn = mg_connect(host, port, use_ssl, ebuf, ebuf_len)) == NULL) { } else if (mg_vprintf(conn, fmt, ap) <= 0) { snprintf(ebuf, ebuf_len, "%s", "Error sending request"); } else { msg = getreq(conn); } if (msg != NULL && conn != NULL) { mg_close_connection(conn); conn = NULL; } return conn; } static const struct { const char *extension; size_t ext_len; const char *mime_type; } builtin_mime_types[] = { {".html", 5, "text/html"}, {".htm", 4, "text/html"}, {".shtm", 5, "text/html"}, {".shtml", 6, "text/html"}, {".css", 4, "text/css"}, {".js", 3, "application/x-javascript"}, {".ico", 4, "image/x-icon"}, {".gif", 4, "image/gif"}, {".jpg", 4, "image/jpeg"}, {".jpeg", 5, "image/jpeg"}, {".png", 4, "image/png"}, {".svg", 4, "image/svg+xml"}, {".txt", 4, "text/plain"}, {".torrent", 8, "application/x-bittorrent"}, {".wav", 4, "audio/x-wav"}, {".mp3", 4, "audio/x-mp3"}, {".mid", 4, "audio/mid"}, {".m3u", 4, "audio/x-mpegurl"}, {".ogg", 4, "application/ogg"}, {".ram", 4, "audio/x-pn-realaudio"}, {".xml", 4, "text/xml"}, {".json", 5, "text/json"}, {".xslt", 5, "application/xml"}, {".xsl", 4, "application/xml"}, {".ra", 3, "audio/x-pn-realaudio"}, {".doc", 4, "application/msword"}, {".exe", 4, "application/octet-stream"}, {".zip", 4, "application/x-zip-compressed"}, {".xls", 4, "application/excel"}, {".tgz", 4, "application/x-tar-gz"}, {".tar", 4, "application/x-tar"}, {".gz", 3, "application/x-gunzip"}, {".arj", 4, "application/x-arj-compressed"}, {".rar", 4, "application/x-arj-compressed"}, {".rtf", 4, "application/rtf"}, {".pdf", 4, "application/pdf"}, {".swf", 4, "application/x-shockwave-flash"}, {".mpg", 4, "video/mpeg"}, {".webm", 5, "video/webm"}, {".mpeg", 5, "video/mpeg"}, {".mov", 4, "video/quicktime"}, {".mp4", 4, "video/mp4"}, {".m4v", 4, "video/x-m4v"}, {".asf", 4, "video/x-ms-asf"}, {".avi", 4, "video/x-msvideo"}, {".bmp", 4, "image/bmp"}, {".ttf", 4, "application/x-font-ttf"}, {NULL, 0, NULL} }; const char *mg_get_builtin_mime_type(const char *path) { const char *ext; size_t i, path_len; path_len = strlen(path); for (i = 0; builtin_mime_types[i].extension != NULL; i++) { ext = path + (path_len - builtin_mime_types[i].ext_len); if (path_len > builtin_mime_types[i].ext_len && mg_strcasecmp(ext, builtin_mime_types[i].extension) == 0) { return builtin_mime_types[i].mime_type; } } return "text/plain"; } // Look at the "path" extension and figure what mime type it has. // Store mime type in the vector. static void get_mime_type(struct mg_context *ctx, const char *path, struct vec *vec) { struct vec ext_vec, mime_vec; const char *list, *ext; size_t path_len; path_len = strlen(path); // Scan user-defined mime types first, in case user wants to // override default mime types. list = ctx->config[EXTRA_MIME_TYPES]; while ((list = next_option(list, &ext_vec, &mime_vec)) != NULL) { // ext now points to the path suffix ext = path + path_len - ext_vec.len; if (mg_strncasecmp(ext, ext_vec.ptr, ext_vec.len) == 0) { *vec = mime_vec; return; } } vec->ptr = mg_get_builtin_mime_type(path); vec->len = strlen(vec->ptr); } static void print_dir_entry(const struct de *de) { char size[64], mod[64], href[PATH_MAX * 3]; const char *slash = de->file.is_directory ? "/" : ""; if (de->file.is_directory) { mg_snprintf(size, sizeof(size), "%s", "[DIRECTORY]"); } else { // We use (signed) cast below because MSVC 6 compiler cannot // convert unsigned __int64 to double. Sigh. if (de->file.size < 1024) { mg_snprintf(size, sizeof(size), "%d", (int) de->file.size); } else if (de->file.size < 0x100000) { mg_snprintf(size, sizeof(size), "%.1fk", (double) de->file.size / 1024.0); } else if (de->file.size < 0x40000000) { mg_snprintf(size, sizeof(size), "%.1fM", (double) de->file.size / 1048576); } else { mg_snprintf(size, sizeof(size), "%.1fG", (double) de->file.size / 1073741824); } } strftime(mod, sizeof(mod), "%d-%b-%Y %H:%M", localtime(&de->file.modification_time)); mg_url_encode(de->file_name, href, sizeof(href)); de->conn->num_bytes_sent += mg_chunked_printf(de->conn, "%s%s" " %s  %s\n", de->conn->request_info.uri, href, slash, de->file_name, slash, mod, size); } // This function is called from send_directory() and used for // sorting directory entries by size, or name, or modification time. // On windows, __cdecl specification is needed in case if project is built // with __stdcall convention. qsort always requires __cdels callback. static int WINCDECL compare_dir_entries(const void *p1, const void *p2) { const struct de *a = (const struct de *) p1, *b = (const struct de *) p2; const char *query_string = a->conn->request_info.query_string; int cmp_result = 0; if (query_string == NULL) { query_string = "na"; } if (a->file.is_directory && !b->file.is_directory) { return -1; // Always put directories on top } else if (!a->file.is_directory && b->file.is_directory) { return 1; // Always put directories on top } else if (*query_string == 'n') { cmp_result = strcmp(a->file_name, b->file_name); } else if (*query_string == 's') { cmp_result = a->file.size == b->file.size ? 0 : a->file.size > b->file.size ? 1 : -1; } else if (*query_string == 'd') { cmp_result = a->file.modification_time == b->file.modification_time ? 0 : a->file.modification_time > b->file.modification_time ? 1 : -1; } return query_string[1] == 'd' ? -cmp_result : cmp_result; } static int must_hide_file(struct mg_connection *conn, const char *path) { const char *pw_pattern = "**" PASSWORDS_FILE_NAME "$"; const char *pattern = conn->ctx->config[HIDE_FILES]; return match_prefix(pw_pattern, strlen(pw_pattern), path) > 0 || (pattern != NULL && match_prefix(pattern, strlen(pattern), path) > 0); } static int scan_directory(struct mg_connection *conn, const char *dir, void *data, void (*cb)(struct de *, void *)) { char path[PATH_MAX]; struct dirent *dp; DIR *dirp; struct de de; if ((dirp = opendir(dir)) == NULL) { return 0; } else { de.conn = conn; while ((dp = readdir(dirp)) != NULL) { // Do not show current dir and hidden files if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, "..") || must_hide_file(conn, dp->d_name)) { continue; } mg_snprintf(path, sizeof(path), "%s%c%s", dir, '/', dp->d_name); // If we don't memset stat structure to zero, mtime will have // garbage and strftime() will segfault later on in // print_dir_entry(). memset is required only if mg_stat() // fails. For more details, see // http://code.google.com/p/mongoose/issues/detail?id=79 memset(&de.file, 0, sizeof(de.file)); mg_stat(path, &de.file); de.file_name = dp->d_name; cb(&de, data); } (void) closedir(dirp); } return 1; } static int remove_directory(struct mg_connection *conn, const char *dir) { char path[PATH_MAX]; struct dirent *dp; DIR *dirp; struct de de; if ((dirp = opendir(dir)) == NULL) { return 0; } else { de.conn = conn; while ((dp = readdir(dirp)) != NULL) { // Do not show current dir, but show hidden files if (!strcmp(dp->d_name, ".") || !strcmp(dp->d_name, "..")) { continue; } mg_snprintf(path, sizeof(path), "%s%c%s", dir, '/', dp->d_name); // If we don't memset stat structure to zero, mtime will have // garbage and strftime() will segfault later on in // print_dir_entry(). memset is required only if mg_stat() // fails. For more details, see // http://code.google.com/p/mongoose/issues/detail?id=79 memset(&de.file, 0, sizeof(de.file)); mg_stat(path, &de.file); if(de.file.modification_time) { if(de.file.is_directory) { remove_directory(conn, path); } else { mg_remove(path); } } } (void) closedir(dirp); rmdir(dir); } return 1; } struct dir_scan_data { struct de *entries; int num_entries; int arr_size; }; // Behaves like realloc(), but frees original pointer on failure static void *realloc2(void *ptr, size_t size) { void *new_ptr = realloc(ptr, size); if (new_ptr == NULL) { free(ptr); } return new_ptr; } static void dir_scan_callback(struct de *de, void *data) { struct dir_scan_data *dsd = (struct dir_scan_data *) data; if (dsd->entries == NULL || dsd->num_entries >= dsd->arr_size) { dsd->arr_size *= 2; dsd->entries = (struct de *) realloc2(dsd->entries, dsd->arr_size * sizeof(dsd->entries[0])); } if (dsd->entries == NULL) { // TODO(lsm): propagate an error to the caller dsd->num_entries = 0; } else { dsd->entries[dsd->num_entries].file_name = mg_strdup(de->file_name); dsd->entries[dsd->num_entries].file = de->file; dsd->entries[dsd->num_entries].conn = de->conn; dsd->num_entries++; } } static void handle_directory_request(struct mg_connection *conn, const char *dir) { int i, sort_direction; struct dir_scan_data data = { NULL, 0, 128 }; if (!scan_directory(conn, dir, &data, dir_scan_callback)) { send_http_error(conn, 500, "Cannot open directory", "Error: opendir(%s): %s", dir, strerror(ERRNO)); return; } sort_direction = conn->request_info.query_string != NULL && conn->request_info.query_string[1] == 'd' ? 'a' : 'd'; conn->must_close = 1; mg_printf(conn, "%s", "HTTP/1.1 200 OK\r\n" "Transfer-Encoding: Chunked\r\n" "Content-Type: text/html; charset=utf-8\r\n\r\n"); conn->num_bytes_sent += mg_chunked_printf(conn, "Index of %s" "" "

Index of %s

"
      ""
      ""
      ""
      "",
      conn->request_info.uri, conn->request_info.uri,
      sort_direction, sort_direction, sort_direction);

  // Print first entry - link to a parent directory
  conn->num_bytes_sent += mg_chunked_printf(conn,
      ""
      "\n",
      conn->request_info.uri, "..", "Parent directory", "-", "-");

  // Sort and print directory entries
  qsort(data.entries, (size_t) data.num_entries, sizeof(data.entries[0]),
        compare_dir_entries);
  for (i = 0; i < data.num_entries; i++) {
    print_dir_entry(&data.entries[i]);
    free(data.entries[i].file_name);
  }
  free(data.entries);

  conn->num_bytes_sent += mg_chunked_printf(conn, "%s",
                                            "
NameModifiedSize
%s %s  %s
");
  conn->num_bytes_sent += mg_write(conn, "0\r\n\r\n", 5);
  conn->status_code = 200;
}

// For a given PUT path, create all intermediate subdirectories
// for given path. Return 0 if the path itself is a directory,
// or -1 on error, 1 if OK.
static int put_dir(const char *path) {
  char buf[PATH_MAX];
  const char *s, *p;
  struct file file = STRUCT_FILE_INITIALIZER;
  int len, res = 1;

  for (s = p = path + 2; (p = strchr(s, '/')) != NULL; s = ++p) {
    len = p - path;
    if (len >= (int) sizeof(buf)) {
      res = -1;
      break;
    }
    memcpy(buf, path, len);
    buf[len] = '\0';

    // Try to create intermediate directory
    DEBUG_TRACE(("mkdir(%s)", buf));
    if (!mg_stat(buf, &file) && mg_mkdir(buf, 0755) != 0) {
      res = -1;
      break;
    }

    // Is path itself a directory?
    if (p[1] == '\0') {
      res = 0;
    }
  }

  return res;
}

static void log_header(const struct mg_connection *conn, const char *header,
                       FILE *fp) {
  const char *header_value;

  if ((header_value = mg_get_header(conn, header)) == NULL) {
    (void) fprintf(fp, "%s", " -");
  } else {
    (void) fprintf(fp, " \"%s\"", header_value);
  }
}

static void log_access(const struct mg_connection *conn) {
  const struct mg_request_info *ri;
  FILE *fp;
  char date[64], src_addr[IP_ADDR_STR_LEN];

  fp = conn->ctx->config[ACCESS_LOG_FILE] == NULL ?  NULL :
    fopen(conn->ctx->config[ACCESS_LOG_FILE], "a+");

  if (fp == NULL)
    return;

  strftime(date, sizeof(date), "%d/%b/%Y:%H:%M:%S %z",
           localtime(&conn->birth_time));

  ri = &conn->request_info;
  flockfile(fp);

  sockaddr_to_string(src_addr, sizeof(src_addr), &conn->client.rsa);
  fprintf(fp, "%s - %s [%s] \"%s %s HTTP/%s\" %d %" INT64_FMT,
          src_addr, ri->remote_user == NULL ? "-" : ri->remote_user, date,
          ri->request_method ? ri->request_method : "-",
          ri->uri ? ri->uri : "-", ri->http_version,
          conn->status_code, conn->num_bytes_sent);
  log_header(conn, "Referer", fp);
  log_header(conn, "User-Agent", fp);
  fputc('\n', fp);
  fflush(fp);

  funlockfile(fp);
  fclose(fp);
}

// Parse HTTP headers from the given buffer, advance buffer to the point
// where parsing stopped.
static void parse_http_headers(char **buf, struct mg_request_info *ri) {
  int i;

  for (i = 0; i < (int) ARRAY_SIZE(ri->http_headers); i++) {
    ri->http_headers[i].name = skip_quoted(buf, ":", " ", 0);
    ri->http_headers[i].value = skip(buf, "\r\n");
    if (ri->http_headers[i].name[0] == '\0')
      break;
    ri->num_headers = i + 1;
  }
}

static int is_valid_http_method(const char *method) {
  return !strcmp(method, "GET") || !strcmp(method, "POST") ||
    !strcmp(method, "HEAD") || !strcmp(method, "CONNECT") ||
    !strcmp(method, "PUT") || !strcmp(method, "DELETE") ||
    !strcmp(method, "OPTIONS") || !strcmp(method, "PROPFIND")
    || !strcmp(method, "MKCOL");
}

// Parse HTTP request, fill in mg_request_info structure.
// This function modifies the buffer by NUL-terminating
// HTTP request components, header names and header values.
static int parse_http_message(char *buf, int len, struct mg_request_info *ri) {
  int is_request, request_length = get_request_len(buf, len);
  if (request_length > 0) {
    // Reset attributes. DO NOT TOUCH is_ssl, remote_ip, remote_port
    ri->remote_user = ri->request_method = ri->uri = ri->http_version = NULL;
    ri->num_headers = 0;

    buf[request_length - 1] = '\0';

    // RFC says that all initial whitespaces should be ingored
    while (*buf != '\0' && isspace(* (unsigned char *) buf)) {
      buf++;
    }
    ri->request_method = skip(&buf, " ");
    ri->uri = skip(&buf, " ");
    ri->http_version = skip(&buf, "\r\n");

    // HTTP message could be either HTTP request or HTTP response, e.g.
    // "GET / HTTP/1.0 ...." or  "HTTP/1.0 200 OK ..."
    is_request = is_valid_http_method(ri->request_method);
    if ((is_request && memcmp(ri->http_version, "HTTP/", 5) != 0) ||
        (!is_request && memcmp(ri->request_method, "HTTP/", 5) != 0)) {
      request_length = -1;
    } else {
      if (is_request) {
        ri->http_version += 5;
      }
      parse_http_headers(&buf, ri);
    }
  }
  return request_length;
}

static int parse_range_header(const char *header, int64_t *a, int64_t *b) {
  return sscanf(header, "bytes=%" INT64_FMT "-%" INT64_FMT, a, b);
}

// Return number of bytes left to read for this connection
static int64_t left_to_read(const struct mg_connection *conn) {
  return conn->content_len + conn->request_len - conn->num_bytes_read;
}

// Write data to the IO channel - opened file descriptor, socket or SSL
// descriptor. Return number of bytes written.
static int64_t push(FILE *fp, SOCKET sock, SSL *ssl, const char *buf,
                    int64_t len) {
  int64_t sent;
  int n, k;

  (void) ssl;  // Get rid of warning
  sent = 0;
  while (sent < len) {

    // How many bytes we send in this iteration
    k = len - sent > INT_MAX ? INT_MAX : (int) (len - sent);

#if !defined(NO_SSL)
    if (ssl != NULL) {
      n = SSL_write(ssl, buf + sent, k);
    } else
#endif
    if (fp != NULL) {
      n = (int) fwrite(buf + sent, 1, (size_t) k, fp);
      if (ferror(fp))
        n = -1;
    } else {
      n = send(sock, buf + sent, (size_t) k, MSG_NOSIGNAL);
    }

    if (n <= 0)
      break;

    sent += n;
  }

  return sent;
}

// Read from IO channel - opened file descriptor, socket, or SSL descriptor.
// Return negative value on error, or number of bytes read on success.
static int pull(FILE *fp, struct mg_connection *conn, char *buf, int len) {
  int nread;

  if (len <= 0) return 0;
  if (fp != NULL) {
    // Use read() instead of fread(), because if we're reading from the CGI
    // pipe, fread() may block until IO buffer is filled up. We cannot afford
    // to block and must pass all read bytes immediately to the client.
    nread = read(fileno(fp), buf, (size_t) len);
#ifndef NO_SSL
  } else if (conn->ssl != NULL) {
    nread = SSL_read(conn->ssl, buf, len);
#endif
  } else {
    nread = recv(conn->client.sock, buf, (size_t) len, 0);
  }
  if (nread > 0) {
    conn->num_bytes_read += nread;
  }

  return conn->ctx->stop_flag ? -1 : nread;
}

static int pull_all(FILE *fp, struct mg_connection *conn, char *buf, int len) {
  int n, nread = 0;

  while (len > 0 && conn->ctx->stop_flag == 0) {
    n = pull(fp, conn, buf + nread, len);
    if (n < 0) {
      nread = n;  // Propagate the error
      break;
    } else if (n == 0) {
      break;  // No more data to read
    } else {
      nread += n;
      len -= n;
    }
  }

  return nread;
}

int mg_read(struct mg_connection *conn, void *buf, int len) {
  int n, buffered_len, nread = 0;
  int64_t left;

  if (conn->content_len <= 0) {
    return 0;
  }

  // conn->buf           body
  //    |=================|==========|===============|
  //    |<--request_len-->|                          |
  //    |<-----------data_len------->|      conn->buf + conn->buf_size

  // First, check for data buffered in conn->buf by read_request().
  if (len > 0 && (buffered_len = conn->data_len - conn->request_len) > 0) {
    char *body = conn->buf + conn->request_len;
    if (buffered_len > len) buffered_len = len;
    if (buffered_len > conn->content_len) buffered_len = (int)conn->content_len;

    memcpy(buf, body, (size_t) buffered_len);
    memmove(body, body + buffered_len,
            &conn->buf[conn->data_len] - &body[buffered_len]);
    len -= buffered_len;
    conn->data_len -= buffered_len;
    nread += buffered_len;
  }

  // Read data from the socket.
  if (len > 0 && (left = left_to_read(conn)) > 0) {
    if (left < len) {
      len = (int) left;
    }
    n = pull_all(NULL, conn, (char *) buf + nread, (int) len);
    nread = n >= 0 ? nread + n : n;
  }

  return nread;
}

int mg_write(struct mg_connection *conn, const void *buf, int len) {
  return (int) push(NULL, conn->client.sock, conn->ssl, (const char *) buf,
                    (int64_t) len);
}

// Keep reading the input (either opened file descriptor fd, or socket sock,
// or SSL descriptor ssl) into buffer buf, until \r\n\r\n appears in the
// buffer (which marks the end of HTTP request). Buffer buf may already
// have some data. The length of the data is stored in nread.
// Upon every read operation, increase nread by the number of bytes read.
static int read_request(FILE *fp, struct mg_connection *conn,
                        char *buf, int bufsiz, int *nread) {
  int request_len, n = 0;

  request_len = get_request_len(buf, *nread);
  while (conn->ctx->stop_flag == 0 &&
         *nread < bufsiz &&
         request_len == 0 &&
         (n = pull(fp, conn, buf + *nread, bufsiz - *nread)) > 0) {
    *nread += n;
    assert(*nread <= bufsiz);
    request_len = get_request_len(buf, *nread);
  }

  return request_len <= 0 && n <= 0 ? -1 : request_len;
}

// Send len bytes from the opened file to the client.
static void send_file_data(struct mg_connection *conn, FILE *fp,
                           int64_t offset, int64_t len) {
  char buf[MG_BUF_LEN];
  int num_read, num_written, to_read;

  // If offset is beyond file boundaries, don't send anything
  if (offset > 0 && fseeko(fp, offset, SEEK_SET) != 0) {
    return;
  }

  while (len > 0) {
    // Calculate how much to read from the file in the buffer
    to_read = sizeof(buf);
    if ((int64_t) to_read > len) {
      to_read = (int) len;
    }

    // Read from file, exit the loop on error
    if ((num_read = fread(buf, 1, (size_t) to_read, fp)) <= 0) {
      break;
    }

    // Send read bytes to the client, exit the loop on error
    if ((num_written = mg_write(conn, buf, (size_t) num_read)) != num_read) {
      break;
    }

    // Both read and were successful, adjust counters
    conn->num_bytes_sent += num_written;
    len -= num_written;
  }
}


static int forward_body_data(struct mg_connection *conn, FILE *fp,
                             SOCKET sock, SSL *ssl) {
  const char *expect, *body;
  char buf[MG_BUF_LEN];
  int nread, buffered_len, success = 0;
  int64_t left;

  expect = mg_get_header(conn, "Expect");
  assert(fp != NULL);

  if (conn->content_len == INT64_MAX) {
    send_http_error(conn, 411, "Length Required", "%s", "");
  } else if (expect != NULL && mg_strcasecmp(expect, "100-continue")) {
    send_http_error(conn, 417, "Expectation Failed", "%s", "");
  } else {
    if (expect != NULL) {
      (void) mg_printf(conn, "%s", "HTTP/1.1 100 Continue\r\n\r\n");
    }

    buffered_len = conn->data_len - conn->request_len;
    body = conn->buf + conn->request_len;
    assert(buffered_len >= 0);

    if (buffered_len > 0) {
      if ((int64_t) buffered_len > conn->content_len) {
        buffered_len = (int) conn->content_len;
      }
      push(fp, sock, ssl, body, (int64_t) buffered_len);
      memmove((char *) body, body + buffered_len, buffered_len);
      conn->data_len -= buffered_len;
    }

    nread = 0;
    while (conn->num_bytes_read < conn->content_len + conn->request_len) {
      left = left_to_read(conn);
      if (left > (int64_t) sizeof(buf)) {
        left = sizeof(buf);
      }
      nread = pull(NULL, conn, buf, (int) left);
      if (nread <= 0 || push(fp, sock, ssl, buf, nread) != nread) {
        break;
      }
    }

    if (left_to_read(conn) == 0) {
      success = nread >= 0;
    }

    // Each error code path in this function must send an error
    if (!success) {
      send_http_error(conn, 577, http_500_error, "%s", "");
    }
  }

  return success;
}


#if !defined(NO_CGI)
// This structure helps to create an environment for the spawned CGI program.
// Environment is an array of "VARIABLE=VALUE\0" ASCIIZ strings,
// last element must be NULL.
// However, on Windows there is a requirement that all these VARIABLE=VALUE\0
// strings must reside in a contiguous buffer. The end of the buffer is
// marked by two '\0' characters.
// We satisfy both worlds: we create an envp array (which is vars), all
// entries are actually pointers inside buf.
struct cgi_env_block {
  struct mg_connection *conn;
  char buf[CGI_ENVIRONMENT_SIZE]; // Environment buffer
  int len; // Space taken
  char *vars[MAX_CGI_ENVIR_VARS]; // char **envp
  int nvars; // Number of variables
};

static char *addenv(struct cgi_env_block *block,
                    PRINTF_FORMAT_STRING(const char *fmt), ...)
  PRINTF_ARGS(2, 3);

// Append VARIABLE=VALUE\0 string to the buffer, and add a respective
// pointer into the vars array.
static char *addenv(struct cgi_env_block *block, const char *fmt, ...) {
  int n, space;
  char *added;
  va_list ap;

  // Calculate how much space is left in the buffer
  space = sizeof(block->buf) - block->len - 2;
  assert(space >= 0);

  // Make a pointer to the free space int the buffer
  added = block->buf + block->len;

  // Copy VARIABLE=VALUE\0 string into the free space
  va_start(ap, fmt);
  n = mg_vsnprintf(added, (size_t) space, fmt, ap);
  va_end(ap);

  // Make sure we do not overflow buffer and the envp array
  if (n > 0 && n + 1 < space &&
      block->nvars < (int) ARRAY_SIZE(block->vars) - 2) {
    // Append a pointer to the added string into the envp array
    block->vars[block->nvars++] = added;
    // Bump up used length counter. Include \0 terminator
    block->len += n + 1;
  } else {
    cry(block->conn, "%s: CGI env buffer truncated for [%s]", __func__, fmt);
  }

  return added;
}

static void prepare_cgi_environment(struct mg_connection *conn,
                                    const char *prog,
                                    struct cgi_env_block *blk) {
  const struct mg_request_info *ri = &conn->request_info;
  const char *s, *slash;
  struct vec var_vec;
  char *p, src_addr[IP_ADDR_STR_LEN];
  int  i;

  blk->len = blk->nvars = 0;
  blk->conn = conn;
  sockaddr_to_string(src_addr, sizeof(src_addr), &conn->client.rsa);

  addenv(blk, "SERVER_NAME=%s", conn->ctx->config[AUTHENTICATION_DOMAIN]);
  addenv(blk, "SERVER_ROOT=%s", conn->ctx->config[DOCUMENT_ROOT]);
  addenv(blk, "DOCUMENT_ROOT=%s", conn->ctx->config[DOCUMENT_ROOT]);
  addenv(blk, "SERVER_SOFTWARE=%s/%s", "Mongoose", mg_version());

  // Prepare the environment block
  addenv(blk, "%s", "GATEWAY_INTERFACE=CGI/1.1");
  addenv(blk, "%s", "SERVER_PROTOCOL=HTTP/1.1");
  addenv(blk, "%s", "REDIRECT_STATUS=200"); // For PHP

  // TODO(lsm): fix this for IPv6 case
  addenv(blk, "SERVER_PORT=%d", ntohs(conn->client.lsa.sin.sin_port));

  addenv(blk, "REQUEST_METHOD=%s", ri->request_method);
  addenv(blk, "REMOTE_ADDR=%s", src_addr);
  addenv(blk, "REMOTE_PORT=%d", ri->remote_port);
  addenv(blk, "REQUEST_URI=%s%s%s", ri->uri,
         ri->query_string == NULL ? "" : "?",
         ri->query_string == NULL ? "" : ri->query_string);

  // SCRIPT_NAME
  if (conn->path_info != NULL) {
    addenv(blk, "SCRIPT_NAME=%.*s",
           (int) (strlen(ri->uri) - strlen(conn->path_info)), ri->uri);
    addenv(blk, "PATH_INFO=%s", conn->path_info);
  } else {
    s = strrchr(prog, '/');
    slash = strrchr(ri->uri, '/');
    addenv(blk, "SCRIPT_NAME=%.*s%s",
           slash == NULL ? 0 : (int) (slash - ri->uri), ri->uri,
           s == NULL ? prog : s);
  }

  addenv(blk, "SCRIPT_FILENAME=%s", prog);
  addenv(blk, "PATH_TRANSLATED=%s", prog);
  addenv(blk, "HTTPS=%s", conn->ssl == NULL ? "off" : "on");

  if ((s = mg_get_header(conn, "Content-Type")) != NULL)
    addenv(blk, "CONTENT_TYPE=%s", s);

  if (ri->query_string != NULL) {
    addenv(blk, "QUERY_STRING=%s", ri->query_string);
  }

  if ((s = mg_get_header(conn, "Content-Length")) != NULL)
    addenv(blk, "CONTENT_LENGTH=%s", s);

  if ((s = getenv("PATH")) != NULL)
    addenv(blk, "PATH=%s", s);

#if defined(_WIN32)
  if ((s = getenv("COMSPEC")) != NULL) {
    addenv(blk, "COMSPEC=%s", s);
  }
  if ((s = getenv("SYSTEMROOT")) != NULL) {
    addenv(blk, "SYSTEMROOT=%s", s);
  }
  if ((s = getenv("SystemDrive")) != NULL) {
    addenv(blk, "SystemDrive=%s", s);
  }
  if ((s = getenv("ProgramFiles")) != NULL) {
    addenv(blk, "ProgramFiles=%s", s);
  }
  if ((s = getenv("ProgramFiles(x86)")) != NULL) {
    addenv(blk, "ProgramFiles(x86)=%s", s);
  }
  if ((s = getenv("CommonProgramFiles(x86)")) != NULL) {
    addenv(blk, "CommonProgramFiles(x86)=%s", s);
  }
#else
  if ((s = getenv("LD_LIBRARY_PATH")) != NULL)
    addenv(blk, "LD_LIBRARY_PATH=%s", s);
#endif // _WIN32

  if ((s = getenv("PERLLIB")) != NULL)
    addenv(blk, "PERLLIB=%s", s);

  if (ri->remote_user != NULL) {
    addenv(blk, "REMOTE_USER=%s", ri->remote_user);
    addenv(blk, "%s", "AUTH_TYPE=Digest");
  }

  // Add all headers as HTTP_* variables
  for (i = 0; i < ri->num_headers; i++) {
    p = addenv(blk, "HTTP_%s=%s",
        ri->http_headers[i].name, ri->http_headers[i].value);

    // Convert variable name into uppercase, and change - to _
    for (; *p != '=' && *p != '\0'; p++) {
      if (*p == '-')
        *p = '_';
      *p = (char) toupper(* (unsigned char *) p);
    }
  }

  // Add user-specified variables
  s = conn->ctx->config[CGI_ENVIRONMENT];
  while ((s = next_option(s, &var_vec, NULL)) != NULL) {
    addenv(blk, "%.*s", (int) var_vec.len, var_vec.ptr);
  }

  blk->vars[blk->nvars++] = NULL;
  blk->buf[blk->len++] = '\0';

  assert(blk->nvars < (int) ARRAY_SIZE(blk->vars));
  assert(blk->len > 0);
  assert(blk->len < (int) sizeof(blk->buf));
}

static void handle_cgi_request(struct mg_connection *conn, const char *prog) {
  int headers_len, data_len, i, fdin[2] = {-1, -1}, fdout[2] = {-1, -1};
  const char *status, *status_text;
  char buf[16384], *pbuf, dir[PATH_MAX], *p;
  struct mg_request_info ri;
  struct cgi_env_block blk;
  FILE *in = NULL, *out = NULL;
  pid_t pid = (pid_t) -1;

  memset(&ri, 0, sizeof(ri));
  prepare_cgi_environment(conn, prog, &blk);

  // CGI must be executed in its own directory. 'dir' must point to the
  // directory containing executable program, 'p' must point to the
  // executable program name relative to 'dir'.
  (void) mg_snprintf(dir, sizeof(dir), "%s", prog);
  if ((p = strrchr(dir, '/')) != NULL) {
    *p++ = '\0';
  } else {
    dir[0] = '.', dir[1] = '\0';
    p = (char *) prog;
  }

  if (pipe(fdin) != 0 || pipe(fdout) != 0) {
    send_http_error(conn, 500, http_500_error,
        "Cannot create CGI pipe: %s", strerror(ERRNO));
    goto done;
  }

  pid = spawn_process(conn, p, blk.buf, blk.vars, fdin[0], fdout[1], dir);
  if (pid == (pid_t) -1) {
    send_http_error(conn, 500, http_500_error,
        "Cannot spawn CGI process [%s]: %s", prog, strerror(ERRNO));
    goto done;
  }

  // Make sure child closes all pipe descriptors. It must dup them to 0,1
  set_close_on_exec(fdin[0]);
  set_close_on_exec(fdin[1]);
  set_close_on_exec(fdout[0]);
  set_close_on_exec(fdout[1]);

  // Parent closes only one side of the pipes.
  // If we don't mark them as closed, close() attempt before
  // return from this function throws an exception on Windows.
  // Windows does not like when closed descriptor is closed again.
  (void) close(fdin[0]);
  (void) close(fdout[1]);
  fdin[0] = fdout[1] = -1;


  if ((in = fdopen(fdin[1], "wb")) == NULL ||
      (out = fdopen(fdout[0], "rb")) == NULL) {
    send_http_error(conn, 500, http_500_error,
        "fopen: %s", strerror(ERRNO));
    goto done;
  }

  setbuf(in, NULL);
  setbuf(out, NULL);

  // Send POST data to the CGI process if needed
  if (!strcmp(conn->request_info.request_method, "POST") &&
      !forward_body_data(conn, in, INVALID_SOCKET, NULL)) {
    goto done;
  }

  // Close so child gets an EOF.
  fclose(in);
  in = NULL;
  fdin[1] = -1;

  // Now read CGI reply into a buffer. We need to set correct
  // status code, thus we need to see all HTTP headers first.
  // Do not send anything back to client, until we buffer in all
  // HTTP headers.
  data_len = 0;
  headers_len = read_request(out, conn, buf, sizeof(buf), &data_len);
  if (headers_len <= 0) {
    send_http_error(conn, 500, http_500_error,
                    "CGI program sent malformed or too big (>%u bytes) "
                    "HTTP headers: [%.*s]",
                    (unsigned) sizeof(buf), data_len, buf);
    goto done;
  }
  pbuf = buf;
  buf[headers_len - 1] = '\0';
  parse_http_headers(&pbuf, &ri);

  // Make up and send the status line
  status_text = "OK";
  if ((status = get_header(&ri, "Status")) != NULL) {
    conn->status_code = atoi(status);
    status_text = status;
    while (isdigit(* (unsigned char *) status_text) || *status_text == ' ') {
      status_text++;
    }
  } else if (get_header(&ri, "Location") != NULL) {
    conn->status_code = 302;
  } else {
    conn->status_code = 200;
  }
  if (get_header(&ri, "Connection") != NULL &&
      !mg_strcasecmp(get_header(&ri, "Connection"), "keep-alive")) {
    conn->must_close = 1;
  }
  (void) mg_printf(conn, "HTTP/1.1 %d %s\r\n", conn->status_code,
                   status_text);

  // Send headers
  for (i = 0; i < ri.num_headers; i++) {
    mg_printf(conn, "%s: %s\r\n",
              ri.http_headers[i].name, ri.http_headers[i].value);
  }
  mg_write(conn, "\r\n", 2);

  // Send chunk of data that may have been read after the headers
  conn->num_bytes_sent += mg_write(conn, buf + headers_len,
                                   (size_t)(data_len - headers_len));

  // Read the rest of CGI output and send to the client
  send_file_data(conn, out, 0, INT64_MAX);

done:
  if (pid != (pid_t) -1) {
    kill(pid, SIGKILL);
  }
  if (fdin[0] != -1) {
    close(fdin[0]);
  }
  if (fdout[1] != -1) {
    close(fdout[1]);
  }

  if (in != NULL) {
    fclose(in);
  } else if (fdin[1] != -1) {
    close(fdin[1]);
  }

  if (out != NULL) {
    fclose(out);
  } else if (fdout[0] != -1) {
    close(fdout[0]);
  }
}
#endif // !NO_CGI


FILE *mg_upload(struct mg_connection *conn, const char *destination_dir,
                char *path, int path_len) {
  const char *content_type_header, *boundary_start;
  char *buf, fname[1024], boundary[100], *s, *p;
  int bl, n, i, j, headers_len, boundary_len, eof, buf_len, to_read, len = 0;
  FILE *fp;

  // Request looks like this:
  //
  // POST /upload HTTP/1.1
  // Host: 127.0.0.1:8080
  // Content-Length: 244894
  // Content-Type: multipart/form-data; boundary=----WebKitFormBoundaryRVr
  //
  // ------WebKitFormBoundaryRVr
  // Content-Disposition: form-data; name="file"; filename="accum.png"
  // Content-Type: image/png
  //
  //  <89>PNG
  //  
  // ------WebKitFormBoundaryRVr

  // Extract boundary string from the Content-Type header
  if ((content_type_header = mg_get_header(conn, "Content-Type")) == NULL ||
      (boundary_start = mg_strcasestr(content_type_header,
                                      "boundary=")) == NULL ||
      (sscanf(boundary_start, "boundary=\"%99[^\"]\"", boundary) == 0 &&
       sscanf(boundary_start, "boundary=%99s", boundary) == 0) ||
      boundary[0] == '\0') {
    return NULL;
  }

  boundary_len = strlen(boundary);
  bl = boundary_len + 4;  // \r\n--

  //                     buf
  // conn->buf            |<--------- buf_len ------>|
  //    |=================|==========|===============|
  //    |<--request_len-->|<--len--->|               |
  //    |<-----------data_len------->|      conn->buf + conn->buf_size

  buf = conn->buf + conn->request_len;
  buf_len = conn->buf_size - conn->request_len;
  len = conn->data_len - conn->request_len;

  for (;;) {
    // Pull in headers
    assert(len >= 0 && len <= buf_len);
    to_read = buf_len - len;
    if (to_read > left_to_read(conn)) {
      to_read = (int) left_to_read(conn);
    }
    while (len < buf_len &&
           (n = pull(NULL, conn, buf + len, to_read)) > 0) {
      len += n;
    }
    if ((headers_len = get_request_len(buf, len)) <= 0) {
      break;
    }

    // Fetch file name.
    fname[0] = '\0';
    for (i = j = 0; i < headers_len; i++) {
      if (buf[i] == '\r' && buf[i + 1] == '\n') {
        buf[i] = buf[i + 1] = '\0';
        // TODO(lsm): don't expect filename to be the 3rd field,
        // parse the header properly instead.
        sscanf(&buf[j], "Content-Disposition: %*s %*s filename=\"%1023[^\"]",
               fname);
        j = i + 2;
      }
    }

    // Give up if the headers are not what we expect
    if (fname[0] == '\0') {
      break;
    }

    // Move data to the beginning of the buffer
    assert(len >= headers_len);
    memmove(buf, &buf[headers_len], len - headers_len);
    len -= headers_len;
    conn->data_len = conn->request_len + len;

    // We open the file with exclusive lock held. This guarantee us
    // there is no other thread can save into the same file simultaneously.
    fp = NULL;

    // Construct destination file name. Do not allow paths to have slashes.
    s = fname;
    if ((p = strrchr(fname, '/')) != NULL && p > s) s = p;
    if ((p = strrchr(fname, '\\')) != NULL && p > s) s = p;

    // Open file in binary mode. TODO: set an exclusive lock.
    snprintf(path, path_len, "%s/%s", destination_dir, s);
    if ((fp = fopen(path, "wb")) == NULL) {
      break;
    }

    // Read POST data, write into file until boundary is found.
    eof = n = 0;
    do {
      len += n;
      for (i = 0; i < len - bl; i++) {
        if (!memcmp(&buf[i], "\r\n--", 4) &&
            !memcmp(&buf[i + 4], boundary, boundary_len)) {
          // Found boundary, that's the end of file data.
          fwrite(buf, 1, i, fp);
          eof = 1;
          memmove(buf, &buf[i + bl], len - (i + bl));
          len -= i + bl;
          break;
        }
      }
      if (!eof && len > bl) {
        fwrite(buf, 1, len - bl, fp);
        memmove(buf, &buf[len - bl], bl);
        len = bl;
      }
      to_read = buf_len - len;
      if (to_read > left_to_read(conn)) {
        to_read = (int) left_to_read(conn);
      }
    } while (!eof && (n = pull(NULL, conn, buf + len, to_read)) > 0);
    conn->data_len = conn->request_len + len;

    if (eof) {
      rewind(fp);
      return fp;
    } else {
      fclose(fp);
    }
  }

  return NULL;
}



#if defined(USE_WEBSOCKET)

// START OF SHA-1 code
// Copyright(c) By Steve Reid 
#define SHA1HANDSOFF
#if defined(__sun)
#include "solarisfixes.h"
#endif

union char64long16 { unsigned char c[64]; uint32_t l[16]; };

#define rol(value, bits) (((value) << (bits)) | ((value) >> (32 - (bits))))

static uint32_t blk0(union char64long16 *block, int i) {
  // Forrest: SHA expect BIG_ENDIAN, swap if LITTLE_ENDIAN
  if (!is_big_endian()) {
    block->l[i] = (rol(block->l[i], 24) & 0xFF00FF00) |
      (rol(block->l[i], 8) & 0x00FF00FF);
  }
  return block->l[i];
}

#define blk(i) (block->l[i&15] = rol(block->l[(i+13)&15]^block->l[(i+8)&15] \
    ^block->l[(i+2)&15]^block->l[i&15],1))
#define R0(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk0(block, i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R1(v,w,x,y,z,i) z+=((w&(x^y))^y)+blk(i)+0x5A827999+rol(v,5);w=rol(w,30);
#define R2(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0x6ED9EBA1+rol(v,5);w=rol(w,30);
#define R3(v,w,x,y,z,i) z+=(((w|x)&y)|(w&x))+blk(i)+0x8F1BBCDC+rol(v,5);w=rol(w,30);
#define R4(v,w,x,y,z,i) z+=(w^x^y)+blk(i)+0xCA62C1D6+rol(v,5);w=rol(w,30);

typedef struct {
    uint32_t state[5];
    uint32_t count[2];
    unsigned char buffer[64];
} SHA1_CTX;

static void SHA1Transform(uint32_t state[5], const unsigned char buffer[64]) {
  uint32_t a, b, c, d, e;
  union char64long16 block[1];

  memcpy(block, buffer, 64);
  a = state[0];
  b = state[1];
  c = state[2];
  d = state[3];
  e = state[4];
  R0(a,b,c,d,e, 0); R0(e,a,b,c,d, 1); R0(d,e,a,b,c, 2); R0(c,d,e,a,b, 3);
  R0(b,c,d,e,a, 4); R0(a,b,c,d,e, 5); R0(e,a,b,c,d, 6); R0(d,e,a,b,c, 7);
  R0(c,d,e,a,b, 8); R0(b,c,d,e,a, 9); R0(a,b,c,d,e,10); R0(e,a,b,c,d,11);
  R0(d,e,a,b,c,12); R0(c,d,e,a,b,13); R0(b,c,d,e,a,14); R0(a,b,c,d,e,15);
  R1(e,a,b,c,d,16); R1(d,e,a,b,c,17); R1(c,d,e,a,b,18); R1(b,c,d,e,a,19);
  R2(a,b,c,d,e,20); R2(e,a,b,c,d,21); R2(d,e,a,b,c,22); R2(c,d,e,a,b,23);
  R2(b,c,d,e,a,24); R2(a,b,c,d,e,25); R2(e,a,b,c,d,26); R2(d,e,a,b,c,27);
  R2(c,d,e,a,b,28); R2(b,c,d,e,a,29); R2(a,b,c,d,e,30); R2(e,a,b,c,d,31);
  R2(d,e,a,b,c,32); R2(c,d,e,a,b,33); R2(b,c,d,e,a,34); R2(a,b,c,d,e,35);
  R2(e,a,b,c,d,36); R2(d,e,a,b,c,37); R2(c,d,e,a,b,38); R2(b,c,d,e,a,39);
  R3(a,b,c,d,e,40); R3(e,a,b,c,d,41); R3(d,e,a,b,c,42); R3(c,d,e,a,b,43);
  R3(b,c,d,e,a,44); R3(a,b,c,d,e,45); R3(e,a,b,c,d,46); R3(d,e,a,b,c,47);
  R3(c,d,e,a,b,48); R3(b,c,d,e,a,49); R3(a,b,c,d,e,50); R3(e,a,b,c,d,51);
  R3(d,e,a,b,c,52); R3(c,d,e,a,b,53); R3(b,c,d,e,a,54); R3(a,b,c,d,e,55);
  R3(e,a,b,c,d,56); R3(d,e,a,b,c,57); R3(c,d,e,a,b,58); R3(b,c,d,e,a,59);
  R4(a,b,c,d,e,60); R4(e,a,b,c,d,61); R4(d,e,a,b,c,62); R4(c,d,e,a,b,63);
  R4(b,c,d,e,a,64); R4(a,b,c,d,e,65); R4(e,a,b,c,d,66); R4(d,e,a,b,c,67);
  R4(c,d,e,a,b,68); R4(b,c,d,e,a,69); R4(a,b,c,d,e,70); R4(e,a,b,c,d,71);
  R4(d,e,a,b,c,72); R4(c,d,e,a,b,73); R4(b,c,d,e,a,74); R4(a,b,c,d,e,75);
  R4(e,a,b,c,d,76); R4(d,e,a,b,c,77); R4(c,d,e,a,b,78); R4(b,c,d,e,a,79);
  state[0] += a;
  state[1] += b;
  state[2] += c;
  state[3] += d;
  state[4] += e;
  a = b = c = d = e = 0;
  memset(block, '\0', sizeof(block));
}

static void SHA1Init(SHA1_CTX* context) {
  context->state[0] = 0x67452301;
  context->state[1] = 0xEFCDAB89;
  context->state[2] = 0x98BADCFE;
  context->state[3] = 0x10325476;
  context->state[4] = 0xC3D2E1F0;
  context->count[0] = context->count[1] = 0;
}

static void SHA1Update(SHA1_CTX* context, const unsigned char* data,
                       uint32_t len) {
  uint32_t i, j;

  j = context->count[0];
  if ((context->count[0] += len << 3) < j)
    context->count[1]++;
  context->count[1] += (len>>29);
  j = (j >> 3) & 63;
  if ((j + len) > 63) {
    memcpy(&context->buffer[j], data, (i = 64-j));
    SHA1Transform(context->state, context->buffer);
    for ( ; i + 63 < len; i += 64) {
      SHA1Transform(context->state, &data[i]);
    }
    j = 0;
  }
  else i = 0;
  memcpy(&context->buffer[j], &data[i], len - i);
}

static void SHA1Final(unsigned char digest[20], SHA1_CTX* context) {
  unsigned i;
  unsigned char finalcount[8], c;

  for (i = 0; i < 8; i++) {
    finalcount[i] = (unsigned char)((context->count[(i >= 4 ? 0 : 1)]
                                     >> ((3-(i & 3)) * 8) ) & 255);
  }
  c = 0200;
  SHA1Update(context, &c, 1);
  while ((context->count[0] & 504) != 448) {
    c = 0000;
    SHA1Update(context, &c, 1);
  }
  SHA1Update(context, finalcount, 8);
  for (i = 0; i < 20; i++) {
    digest[i] = (unsigned char)
      ((context->state[i>>2] >> ((3-(i & 3)) * 8) ) & 255);
  }
  memset(context, '\0', sizeof(*context));
  memset(&finalcount, '\0', sizeof(finalcount));
}
// END OF SHA1 CODE

static void base64_encode(const unsigned char *src, int src_len, char *dst) {
  static const char *b64 =
    "ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789+/";
  int i, j, a, b, c;

  for (i = j = 0; i < src_len; i += 3) {
    a = src[i];
    b = i + 1 >= src_len ? 0 : src[i + 1];
    c = i + 2 >= src_len ? 0 : src[i + 2];

    dst[j++] = b64[a >> 2];
    dst[j++] = b64[((a & 3) << 4) | (b >> 4)];
    if (i + 1 < src_len) {
      dst[j++] = b64[(b & 15) << 2 | (c >> 6)];
    }
    if (i + 2 < src_len) {
      dst[j++] = b64[c & 63];
    }
  }
  while (j % 4 != 0) {
    dst[j++] = '=';
  }
  dst[j++] = '\0';
}

void mg_websocket_handshake(struct mg_connection *conn) {
  static const char *magic = "258EAFA5-E914-47DA-95CA-C5AB0DC85B11";
  char buf[100], sha[20], b64_sha[sizeof(sha) * 2];
  SHA1_CTX sha_ctx;

  mg_snprintf(buf, sizeof(buf), "%s%s",
              mg_get_header(conn, "Sec-WebSocket-Key"), magic);
  SHA1Init(&sha_ctx);
  SHA1Update(&sha_ctx, (unsigned char *) buf, strlen(buf));
  SHA1Final((unsigned char *) sha, &sha_ctx);
  base64_encode((unsigned char *) sha, sizeof(sha), b64_sha);
  mg_printf(conn, "%s%s%s",
            "HTTP/1.1 101 Switching Protocols\r\n"
            "Upgrade: websocket\r\n"
            "Connection: Upgrade\r\n"
            "Sec-WebSocket-Accept: ", b64_sha, "\r\n\r\n");
}

int mg_websocket_read(struct mg_connection *conn, int *bits, char **data) {
  // Pointer to the beginning of the portion of the incoming websocket message
  // queue. The original websocket upgrade request is never removed,
  // so the queue begins after it.
  unsigned char *buf = (unsigned char *) conn->buf + conn->request_len;
  int n, stop = 0;
  size_t i, len, mask_len, data_len, header_len, body_len;
  char mask[4];

  assert(conn->content_len == 0);

  // Loop continuously, reading messages from the socket, invoking the callback,
  // and waiting repeatedly until an error occurs.
  while (!stop) {
    header_len = 0;
    // body_len is the length of the entire queue in bytes
    // len is the length of the current message
    // data_len is the length of the current message's data payload
    // header_len is the length of the current message's header
    if ((body_len = conn->data_len - conn->request_len) >= 2) {
      len = buf[1] & 127;
      mask_len = buf[1] & 128 ? 4 : 0;
      if (len < 126 && body_len >= mask_len) {
        data_len = len;
        header_len = 2 + mask_len;
      } else if (len == 126 && body_len >= 4 + mask_len) {
        header_len = 4 + mask_len;
        data_len = ((((int) buf[2]) << 8) + buf[3]);
      } else if (body_len >= 10 + mask_len) {
        header_len = 10 + mask_len;
        data_len = (((uint64_t) htonl(* (uint32_t *) &buf[2])) << 32) +
          htonl(* (uint32_t *) &buf[6]);
      }
    }

    // Data layout is as follows:
    //  conn->buf               buf
    //     v                     v              frame1           | frame2
    //     |---------------------|----------------|--------------|-------
    //     |                     |<--header_len-->|<--data_len-->|
    //     |<-conn->request_len->|<-----body_len----------->|
    //     |<-------------------conn->data_len------------->|

    if (header_len > 0) {
      // Allocate space to hold websocket payload
      if ((*data = malloc(data_len)) == NULL) {
        // Allocation failed, exit the loop and then close the connection
        // TODO: notify user about the failure
        data_len = 0;
        break;
      }

      // Save mask and bits, otherwise it may be clobbered by memmove below
      *bits = buf[0];
      memcpy(mask, buf + header_len - mask_len, mask_len);

      // Read frame payload into the allocated buffer.
      assert(body_len >= header_len);
      if (data_len + header_len > body_len) {
        len = body_len - header_len;
        memcpy(*data, buf + header_len, len);
        // TODO: handle pull error
        pull_all(NULL, conn, *data + len, data_len - len);
        conn->data_len = conn->request_len;
      } else {
        len = data_len + header_len;
        memcpy(*data, buf + header_len, data_len);
        memmove(buf, buf + len, body_len - len);
        conn->data_len -= len;
      }

      // Apply mask if necessary
      if (mask_len > 0) {
        for (i = 0; i < data_len; i++) {
          (*data)[i] ^= mask[i % 4];
        }
      }

      return data_len;
    } else {
      // Buffering websocket request
      if ((n = pull(NULL, conn, conn->buf + conn->data_len,
                    conn->buf_size - conn->data_len)) <= 0) {
        break;
      }
      conn->data_len += n;
    }
  }

  return 0;
}

int mg_websocket_write(struct mg_connection* conn, int opcode,
                       const char *data, size_t data_len) {
    unsigned char *copy;
    size_t copy_len = 0;
    int retval = -1;

    if ((copy = (unsigned char *) malloc(data_len + 10)) == NULL) {
      return -1;
    }

    copy[0] = 0x80 + (opcode & 0x0f);

    // Frame format: http://tools.ietf.org/html/rfc6455#section-5.2
    if (data_len < 126) {
      // Inline 7-bit length field
      copy[1] = data_len;
      memcpy(copy + 2, data, data_len);
      copy_len = 2 + data_len;
    } else if (data_len <= 0xFFFF) {
      // 16-bit length field
      copy[1] = 126;
      * (uint16_t *) (copy + 2) = htons(data_len);
      memcpy(copy + 4, data, data_len);
      copy_len = 4 + data_len;
    } else {
      // 64-bit length field
      copy[1] = 127;
      * (uint32_t *) (copy + 2) = htonl((uint64_t) data_len >> 32);
      * (uint32_t *) (copy + 6) = htonl(data_len & 0xffffffff);
      memcpy(copy + 10, data, data_len);
      copy_len = 10 + data_len;
    }

    // Not thread safe
    if (copy_len > 0) {
      retval = mg_write(conn, copy, copy_len);
    }
    free(copy);

    return retval;
}
#endif // !USE_WEBSOCKET


// Writes PROPFIND properties for a collection element
static void print_props(struct mg_connection *conn, const char* uri,
                        struct file *filep) {
  char mtime[64];
  gmt_time_string(mtime, sizeof(mtime), &filep->modification_time);
  conn->num_bytes_sent += mg_printf(conn,
      ""
       "%s"
       ""
        ""
         "%s"
         "%" INT64_FMT ""
         "%s"
        ""
        "HTTP/1.1 200 OK"
       ""
      "\n",
      uri,
      filep->is_directory ? "" : "",
      filep->size,
      mtime);
}

static void print_dav_dir_entry(struct de *de, void *data) {
  char href[PATH_MAX];
  char href_encoded[PATH_MAX];
  struct mg_connection *conn = (struct mg_connection *) data;
  mg_snprintf(href, sizeof(href), "%s%s",
              conn->request_info.uri, de->file_name);
  mg_url_encode(href, href_encoded, PATH_MAX-1);
  print_props(conn, href_encoded, &de->file);
}

static void handle_propfind(struct mg_connection *conn, const char *path,
                            struct file *filep) {
  const char *depth = mg_get_header(conn, "Depth");

  conn->must_close = 1;
  conn->status_code = 207;
  mg_printf(conn, "HTTP/1.1 207 Multi-Status\r\n"
            "Connection: close\r\n"
            "Content-Type: text/xml; charset=utf-8\r\n\r\n");

  conn->num_bytes_sent += mg_printf(conn,
      ""
      "\n");

  // Print properties for the requested resource itself
  print_props(conn, conn->request_info.uri, filep);

  // If it is a directory, print directory entries too if Depth is not 0
  if (filep->is_directory &&
      !mg_strcasecmp(conn->ctx->config[ENABLE_DIRECTORY_LISTING], "yes") &&
      (depth == NULL || strcmp(depth, "0") != 0)) {
    scan_directory(conn, path, conn, &print_dav_dir_entry);
  }

  conn->num_bytes_sent += mg_printf(conn, "%s\n", "");
}

static int call_user(int type, struct mg_connection *conn, void *p) {
  if (conn != NULL && conn->ctx != NULL) {
    conn->event.user_data = conn->ctx->user_data;
    conn->event.type = type;
    conn->event.event_param = p;
    conn->event.request_info = &conn->request_info;
    conn->event.conn = conn;
  }
  return conn == NULL || conn->ctx == NULL || conn->ctx->event_handler == NULL ?
    0 : conn->ctx->event_handler(&conn->event);
}

static int mg_socketpair(sock_t sp[2]) {
  struct sockaddr_in sa;
  sock_t sock, ret = -1;
  socklen_t len = sizeof(sa);

  sp[0] = sp[1] = INVALID_SOCKET;

  (void) memset(&sa, 0, sizeof(sa));
  sa.sin_family = AF_INET;
  sa.sin_port = htons(0);
  sa.sin_addr.s_addr = htonl(0x7f000001);

  if ((sock = socket(AF_INET, SOCK_STREAM, 0)) != INVALID_SOCKET &&
      !bind(sock, (struct sockaddr *) &sa, len) &&
      !listen(sock, 1) &&
      !getsockname(sock, (struct sockaddr *) &sa, &len) &&
      (sp[0] = socket(AF_INET, SOCK_STREAM, 6)) != -1 &&
      !connect(sp[0], (struct sockaddr *) &sa, len) &&
      (sp[1] = accept(sock,(struct sockaddr *) &sa, &len)) != INVALID_SOCKET) {
    set_close_on_exec(sp[0]);
    set_close_on_exec(sp[1]);
    ret = 0;
  } else {
    if (sp[0] != INVALID_SOCKET) closesocket(sp[0]);
    if (sp[1] != INVALID_SOCKET) closesocket(sp[1]);
    sp[0] = sp[1] = INVALID_SOCKET;
  }
  closesocket(sock);

  return ret;
}

static FILE *mg_fopen(const char *path, const char *mode) {
#ifdef _WIN32
  wchar_t wbuf[PATH_MAX], wmode[20];
  to_unicode(path, wbuf, ARRAY_SIZE(wbuf));
  MultiByteToWideChar(CP_UTF8, 0, mode, -1, wmode, ARRAY_SIZE(wmode));
  return _wfopen(wbuf, wmode);
#else
  return fopen(path, mode);
#endif
}

// Print error message to the opened error log stream.
static void cry(struct mg_connection *conn, const char *fmt, ...) {
  char buf[MG_BUF_LEN], src_addr[IP_ADDR_STR_LEN];
  va_list ap;
  FILE *fp;
  time_t timestamp;

  va_start(ap, fmt);
  (void) vsnprintf(buf, sizeof(buf), fmt, ap);
  va_end(ap);

  // Do not lock when getting the callback value, here and below.
  // I suppose this is fine, since function cannot disappear in the
  // same way string option can.
  if (call_user(MG_EVENT_LOG, conn, buf) == 0) {
    fp = conn->ctx == NULL || conn->ctx->config[ERROR_LOG_FILE] == NULL ? NULL :
      fopen(conn->ctx->config[ERROR_LOG_FILE], "a+");

    if (fp != NULL) {
      flockfile(fp);
      timestamp = time(NULL);

      sockaddr_to_string(src_addr, sizeof(src_addr), &conn->client.rsa);
      fprintf(fp, "[%010lu] [error] [client %s] ", (unsigned long) timestamp,
              src_addr);

      if (conn->request_info.request_method != NULL) {
        fprintf(fp, "%s %s: ", conn->request_info.request_method,
                conn->request_info.uri);
      }

      fprintf(fp, "%s", buf);
      fputc('\n', fp);
      funlockfile(fp);
      fclose(fp);
    }
  }
}

const char *mg_version(void) {
  return MONGOOSE_VERSION;
}

// HTTP 1.1 assumes keep alive if "Connection:" header is not set
// This function must tolerate situations when connection info is not
// set up, for example if request parsing failed.
static int should_keep_alive(const struct mg_connection *conn) {
  const char *http_version = conn->request_info.http_version;
  const char *header = mg_get_header(conn, "Connection");
  if (conn->must_close ||
      conn->status_code == 401 ||
      mg_strcasecmp(conn->ctx->config[ENABLE_KEEP_ALIVE], "yes") != 0 ||
      (header != NULL && mg_strcasecmp(header, "keep-alive") != 0) ||
      (header == NULL && http_version && strcmp(http_version, "1.1"))) {
    return 0;
  }
  return 1;
}

static const char *suggest_connection_header(const struct mg_connection *conn) {
  return should_keep_alive(conn) ? "keep-alive" : "close";
}

static void send_http_error(struct mg_connection *conn, int status,
                            const char *reason, const char *fmt, ...) {
  char buf[MG_BUF_LEN];
  va_list ap;
  int len = 0;

  conn->status_code = status;
  buf[0] = '\0';

  // Errors 1xx, 204 and 304 MUST NOT send a body
  if (status > 199 && status != 204 && status != 304) {
    len = mg_snprintf(buf, sizeof(buf), "Error %d: %s", status, reason);
    buf[len++] = '\n';

    va_start(ap, fmt);
    len += mg_vsnprintf(buf + len, sizeof(buf) - len, fmt, ap);
    va_end(ap);
  }
  DEBUG_TRACE(("[%s]", buf));

  if (call_user(MG_HTTP_ERROR, conn, (void *) (long) status) == 0) {
    mg_printf(conn, "HTTP/1.1 %d %s\r\n"
              "Content-Length: %d\r\n"
              "Connection: %s\r\n\r\n", status, reason, len,
              suggest_connection_header(conn));
    conn->num_bytes_sent += mg_printf(conn, "%s", buf);
  }

  if (status >= 500) {
    conn->must_close = 1;
  }
}

// Return 1 if real file has been found, 0 otherwise
static int convert_uri_to_file_name(struct mg_connection *conn, char *buf,
                                    size_t buf_len, struct file *filep) {
  struct vec a, b;
  const char *rewrite, *uri = conn->request_info.uri,
        *root = conn->ctx->config[DOCUMENT_ROOT];
  char *p;
  int match_len;
  char gz_path[PATH_MAX];
  char const* accept_encoding;

  // No filesystem access
  if (root == NULL) {
    return 0;
  }

  // Using buf_len - 1 because memmove() for PATH_INFO may shift part
  // of the path one byte on the right.
  // If document_root is NULL, leave the file empty.
  mg_snprintf(buf, buf_len - 1, "%s%s", root, uri);

  rewrite = conn->ctx->config[REWRITE];
  while ((rewrite = next_option(rewrite, &a, &b)) != NULL) {
    if ((match_len = match_prefix(a.ptr, a.len, uri)) > 0) {
      mg_snprintf(buf, buf_len - 1, "%.*s%s", (int) b.len, b.ptr,
                  uri + match_len);
      break;
    }
  }

  if (mg_stat(buf, filep)) {
    return 1;
  }

  // if we can't find the actual file, look for the file
  // with the same name but a .gz extension. If we find it,
  // use that and set the gzipped flag in the file struct
  // to indicate that the response need to have the content-
  // encoding: gzip header
  // we can only do this if the browser declares support
  if ((accept_encoding = mg_get_header(conn, "Accept-Encoding")) != NULL) {
    if (strstr(accept_encoding,"gzip") != NULL) {
      snprintf(gz_path, sizeof(gz_path), "%s.gz", buf);
      if (mg_stat(gz_path, filep)) {
        filep->gzipped = 1;
        return 1;
      }
    }
  }

  // Support PATH_INFO for CGI scripts.
  for (p = buf + strlen(root == NULL ? "" : root); *p != '\0'; p++) {
    if (*p == '/') {
      *p = '\0';
      if (match_prefix(conn->ctx->config[CGI_EXTENSIONS],
                       strlen(conn->ctx->config[CGI_EXTENSIONS]), buf) > 0 &&
          mg_stat(buf, filep)) {
        // Shift PATH_INFO block one character right, e.g.
        //  "/x.cgi/foo/bar\x00" => "/x.cgi\x00/foo/bar\x00"
        // conn->path_info is pointing to the local variable "path" declared
        // in handle_request(), so PATH_INFO is not valid after
        // handle_request returns.
        conn->path_info = p + 1;
        memmove(p + 2, p + 1, strlen(p + 1) + 1);  // +1 is for trailing \0
        p[1] = '/';
        return 1;
      } else {
        *p = '/';
      }
    }
  }

  return 0;
}

static void construct_etag(char *buf, size_t buf_len,
                           const struct file *filep) {
  snprintf(buf, buf_len, "\"%lx.%" INT64_FMT "\"",
           (unsigned long) filep->modification_time, filep->size);
}

static void fclose_on_exec(FILE *fp) {
  if (fp != NULL) {
#ifndef _WIN32
    fcntl(fileno(fp), F_SETFD, FD_CLOEXEC);
#endif
  }
}

static void handle_file_request(struct mg_connection *conn, const char *path,
                                struct file *filep) {
  char date[64], lm[64], etag[64], range[64];
  const char *msg = "OK", *hdr;
  time_t curtime = time(NULL);
  int64_t cl, r1, r2;
  struct vec mime_vec;
  int n;
  char gz_path[PATH_MAX];
  char const* encoding = "";
  FILE *fp;

  get_mime_type(conn->ctx, path, &mime_vec);
  cl = filep->size;
  conn->status_code = 200;
  range[0] = '\0';

  // if this file is in fact a pre-gzipped file, rewrite its filename
  // it's important to rewrite the filename after resolving
  // the mime type from it, to preserve the actual file's type
  if (filep->gzipped) {
    snprintf(gz_path, sizeof(gz_path), "%s.gz", path);
    path = gz_path;
    encoding = "Content-Encoding: gzip\r\n";
  }

  if ((fp = mg_fopen(path, "rb")) == NULL) {
    send_http_error(conn, 500, http_500_error,
                    "fopen(%s): %s", path, strerror(ERRNO));
    return;
  }

  fclose_on_exec(fp);

  // If Range: header specified, act accordingly
  r1 = r2 = 0;
  hdr = mg_get_header(conn, "Range");
  if (hdr != NULL && (n = parse_range_header(hdr, &r1, &r2)) > 0 &&
      r1 >= 0 && r2 >= 0) {
    // actually, range requests don't play well with a pre-gzipped
    // file (since the range is specified in the uncmpressed space)
    if (filep->gzipped) {
      send_http_error(conn, 501, "Not Implemented",
                      "range requests in gzipped files are not supported");
      return;
    }
    conn->status_code = 206;
    cl = n == 2 ? (r2 > cl ? cl : r2) - r1 + 1: cl - r1;
    mg_snprintf(range, sizeof(range),
                "Content-Range: bytes "
                "%" INT64_FMT "-%"
                INT64_FMT "/%" INT64_FMT "\r\n",
                r1, r1 + cl - 1, filep->size);
    msg = "Partial Content";
  }

  // Prepare Etag, Date, Last-Modified headers. Must be in UTC, according to
  // http://www.w3.org/Protocols/rfc2616/rfc2616-sec3.html#sec3.3
  gmt_time_string(date, sizeof(date), &curtime);
  gmt_time_string(lm, sizeof(lm), &filep->modification_time);
  construct_etag(etag, sizeof(etag), filep);

  (void) mg_printf(conn,
      "HTTP/1.1 %d %s\r\n"
      "Date: %s\r\n"
      "Last-Modified: %s\r\n"
      "Etag: %s\r\n"
      "Content-Type: %.*s\r\n"
      "Content-Length: %" INT64_FMT "\r\n"
      "Connection: %s\r\n"
      "Accept-Ranges: bytes\r\n"
      "%s%s%s\r\n",
      conn->status_code, msg, date, lm, etag, (int) mime_vec.len,
      mime_vec.ptr, cl, suggest_connection_header(conn), range, encoding,
      EXTRA_HTTP_HEADERS);

  if (strcmp(conn->request_info.request_method, "HEAD") != 0) {
    send_file_data(conn, fp, r1, cl);
  }
  fclose(fp);
}

void mg_send_file(struct mg_connection *conn, const char *path) {
  struct file file = STRUCT_FILE_INITIALIZER;
  if (mg_stat(path, &file)) {
    handle_file_request(conn, path, &file);
  } else {
    send_http_error(conn, 404, "Not Found", "%s", "File not found");
  }
}

// For given directory path, substitute it to valid index file.
// Return 0 if index file has been found, -1 if not found.
// If the file is found, it's stats is returned in stp.
static int substitute_index_file(struct mg_connection *conn, char *path,
                                 size_t path_len, struct file *filep) {
  const char *list = conn->ctx->config[INDEX_FILES];
  struct file file = STRUCT_FILE_INITIALIZER;
  struct vec filename_vec;
  size_t n = strlen(path);
  int found = 0;

  // The 'path' given to us points to the directory. Remove all trailing
  // directory separator characters from the end of the path, and
  // then append single directory separator character.
  while (n > 0 && path[n - 1] == '/') {
    n--;
  }
  path[n] = '/';

  // Traverse index files list. For each entry, append it to the given
  // path and see if the file exists. If it exists, break the loop
  while ((list = next_option(list, &filename_vec, NULL)) != NULL) {

    // Ignore too long entries that may overflow path buffer
    if (filename_vec.len > path_len - (n + 2))
      continue;

    // Prepare full path to the index file
    mg_strlcpy(path + n + 1, filename_vec.ptr, filename_vec.len + 1);

    // Does it exist?
    if (mg_stat(path, &file)) {
      // Yes it does, break the loop
      *filep = file;
      found = 1;
      break;
    }
  }

  // If no index file exists, restore directory path
  if (!found) {
    path[n] = '\0';
  }

  return found;
}

// Return True if we should reply 304 Not Modified.
static int is_not_modified(const struct mg_connection *conn,
                           const struct file *filep) {
  char etag[64];
  const char *ims = mg_get_header(conn, "If-Modified-Since");
  const char *inm = mg_get_header(conn, "If-None-Match");
  construct_etag(etag, sizeof(etag), filep);
  return (inm != NULL && !mg_strcasecmp(etag, inm)) ||
    (ims != NULL && filep->modification_time <= parse_date_string(ims));
}

static void mkcol(struct mg_connection *conn, const char *path) {
  int rc, body_len;
  struct de de;

  memset(&de.file, 0, sizeof(de.file));
  mg_stat(path, &de.file);

  if (de.file.modification_time) {
      send_http_error(conn, 405, "Method Not Allowed",
                      "mkcol(%s): %s", path, strerror(ERRNO));
      return;
  }

  body_len = conn->data_len - conn->request_len;
  if(body_len > 0) {
      send_http_error(conn, 415, "Unsupported media type",
                      "mkcol(%s): %s", path, strerror(ERRNO));
      return;
  }

  rc = mg_mkdir(path, 0755);

  if (rc == 0) {
    conn->status_code = 201;
    mg_printf(conn, "HTTP/1.1 %d Created\r\n\r\n", conn->status_code);
  } else if (rc == -1) {
      if(errno == EEXIST)
        send_http_error(conn, 405, "Method Not Allowed",
                      "mkcol(%s): %s", path, strerror(ERRNO));
      else if(errno == EACCES)
          send_http_error(conn, 403, "Forbidden",
                        "mkcol(%s): %s", path, strerror(ERRNO));
      else if(errno == ENOENT)
          send_http_error(conn, 409, "Conflict",
                        "mkcol(%s): %s", path, strerror(ERRNO));
      else
          send_http_error(conn, 500, http_500_error,
                          "fopen(%s): %s", path, strerror(ERRNO));
  }
}

static void put_file(struct mg_connection *conn, const char *path) {
  struct file file = STRUCT_FILE_INITIALIZER;
  FILE *fp;
  const char *range;
  int64_t r1, r2;
  int rc;

  conn->status_code = mg_stat(path, &file) ? 200 : 201;

  if ((rc = put_dir(path)) == 0) {
    mg_printf(conn, "HTTP/1.1 %d OK\r\n\r\n", conn->status_code);
  } else if (rc == -1) {
    send_http_error(conn, 500, http_500_error,
                    "put_dir(%s): %s", path, strerror(ERRNO));
  } else if ((fp = mg_fopen(path, "wb+")) == NULL) {
    fclose(fp);
    send_http_error(conn, 500, http_500_error,
                    "fopen(%s): %s", path, strerror(ERRNO));
  } else {
    fclose_on_exec(fp);
    range = mg_get_header(conn, "Content-Range");
    r1 = r2 = 0;
    if (range != NULL && parse_range_header(range, &r1, &r2) > 0) {
      conn->status_code = 206;
      fseeko(fp, r1, SEEK_SET);
    }
    if (!forward_body_data(conn, fp, INVALID_SOCKET, NULL)) {
      conn->status_code = 500;
    }
    mg_printf(conn, "HTTP/1.1 %d OK\r\nContent-Length: 0\r\n\r\n",
              conn->status_code);
    fclose(fp);
  }
}

static void send_ssi_file(struct mg_connection *, const char *, FILE *, int);
static void do_ssi_include(struct mg_connection *conn, const char *ssi,
                           char *tag, int include_level) {
  char file_name[MG_BUF_LEN], path[PATH_MAX], *p;
  FILE *fp;

  // sscanf() is safe here, since send_ssi_file() also uses buffer
  // of size MG_BUF_LEN to get the tag. So strlen(tag) is always < MG_BUF_LEN.
  if (sscanf(tag, " virtual=\"%[^\"]\"", file_name) == 1) {
    // File name is relative to the webserver root
    (void) mg_snprintf(path, sizeof(path), "%s%c%s",
        conn->ctx->config[DOCUMENT_ROOT], '/', file_name);
  } else if (sscanf(tag, " abspath=\"%[^\"]\"", file_name) == 1) {
    // File name is relative to the webserver working directory
    // or it is absolute system path
    (void) mg_snprintf(path, sizeof(path), "%s", file_name);
  } else if (sscanf(tag, " file=\"%[^\"]\"", file_name) == 1 ||
             sscanf(tag, " \"%[^\"]\"", file_name) == 1) {
    // File name is relative to the currect document
    (void) mg_snprintf(path, sizeof(path), "%s", ssi);
    if ((p = strrchr(path, '/')) != NULL) {
      p[1] = '\0';
    }
    (void) mg_snprintf(path + strlen(path),
        sizeof(path) - strlen(path), "%s", file_name);
  } else {
    cry(conn, "Bad SSI #include: [%s]", tag);
    return;
  }

  if ((fp = mg_fopen(path, "rb")) == NULL) {
    cry(conn, "Cannot open SSI #include: [%s]: fopen(%s): %s",
        tag, path, strerror(ERRNO));
  } else {
    fclose_on_exec(fp);
    if (match_prefix(conn->ctx->config[SSI_EXTENSIONS],
                     strlen(conn->ctx->config[SSI_EXTENSIONS]), path) > 0) {
      send_ssi_file(conn, path, fp, include_level + 1);
    } else {
      send_file_data(conn, fp, 0, INT64_MAX);
    }
    fclose(fp);
  }
}

#if !defined(NO_POPEN)
static void do_ssi_exec(struct mg_connection *conn, char *tag) {
  char cmd[MG_BUF_LEN];
  FILE *fp;

  if (sscanf(tag, " \"%[^\"]\"", cmd) != 1) {
    cry(conn, "Bad SSI #exec: [%s]", tag);
  } else if ((fp = popen(cmd, "r")) == NULL) {
    cry(conn, "Cannot SSI #exec: [%s]: %s", cmd, strerror(ERRNO));
  } else {
    send_file_data(conn, fp, 0, INT64_MAX);
    pclose(fp);
  }
}
#endif // !NO_POPEN

static void send_ssi_file(struct mg_connection *conn, const char *path,
                          FILE *fp, int include_level) {
  char buf[MG_BUF_LEN];
  int ch, offset, len, in_ssi_tag;

  if (include_level > 10) {
    cry(conn, "SSI #include level is too deep (%s)", path);
    return;
  }

  in_ssi_tag = len = offset = 0;
  while ((ch = fgetc(fp)) != EOF) {
    if (in_ssi_tag && ch == '>') {
      in_ssi_tag = 0;
      buf[len++] = (char) ch;
      buf[len] = '\0';
      assert(len <= (int) sizeof(buf));
      if (len < 6 || memcmp(buf, "