nginx/src/http/modules/ngx_http_realip_module.c
2009-02-21 07:02:02 +00:00

419 lines
10 KiB
C

/*
* Copyright (C) Igor Sysoev
*/
#include <ngx_config.h>
#include <ngx_core.h>
#include <ngx_http.h>
#define NGX_HTTP_REALIP_XREALIP 0
#define NGX_HTTP_REALIP_XFWD 1
#define NGX_HTTP_REALIP_HEADER 2
typedef struct {
in_addr_t mask;
in_addr_t addr;
} ngx_http_realip_from_t;
typedef struct {
ngx_array_t *from; /* array of ngx_http_realip_from_t */
ngx_uint_t type;
ngx_uint_t hash;
ngx_str_t header;
} ngx_http_realip_loc_conf_t;
typedef struct {
ngx_connection_t *connection;
in_addr_t addr;
ngx_str_t addr_text;
} ngx_http_realip_ctx_t;
static ngx_int_t ngx_http_realip_handler(ngx_http_request_t *r);
static void ngx_http_realip_cleanup(void *data);
static char *ngx_http_realip_from(ngx_conf_t *cf, ngx_command_t *cmd,
void *conf);
static char *ngx_http_realip(ngx_conf_t *cf, ngx_command_t *cmd, void *conf);
static void *ngx_http_realip_create_loc_conf(ngx_conf_t *cf);
static char *ngx_http_realip_merge_loc_conf(ngx_conf_t *cf,
void *parent, void *child);
static ngx_int_t ngx_http_realip_init(ngx_conf_t *cf);
static ngx_command_t ngx_http_realip_commands[] = {
{ ngx_string("set_real_ip_from"),
NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
ngx_http_realip_from,
NGX_HTTP_LOC_CONF_OFFSET,
0,
NULL },
{ ngx_string("real_ip_header"),
NGX_HTTP_MAIN_CONF|NGX_HTTP_SRV_CONF|NGX_HTTP_LOC_CONF|NGX_CONF_TAKE1,
ngx_http_realip,
NGX_HTTP_LOC_CONF_OFFSET,
0,
NULL },
ngx_null_command
};
static ngx_http_module_t ngx_http_realip_module_ctx = {
NULL, /* preconfiguration */
ngx_http_realip_init, /* postconfiguration */
NULL, /* create main configuration */
NULL, /* init main configuration */
NULL, /* create server configuration */
NULL, /* merge server configuration */
ngx_http_realip_create_loc_conf, /* create location configuration */
ngx_http_realip_merge_loc_conf /* merge location configuration */
};
ngx_module_t ngx_http_realip_module = {
NGX_MODULE_V1,
&ngx_http_realip_module_ctx, /* module context */
ngx_http_realip_commands, /* module directives */
NGX_HTTP_MODULE, /* module type */
NULL, /* init master */
NULL, /* init module */
NULL, /* init process */
NULL, /* init thread */
NULL, /* exit thread */
NULL, /* exit process */
NULL, /* exit master */
NGX_MODULE_V1_PADDING
};
static ngx_int_t
ngx_http_realip_handler(ngx_http_request_t *r)
{
u_char *ip, *p;
size_t len;
in_addr_t addr;
ngx_uint_t i, hash;
ngx_list_part_t *part;
ngx_table_elt_t *header;
struct sockaddr_in *sin;
ngx_connection_t *c;
ngx_pool_cleanup_t *cln;
ngx_http_realip_ctx_t *ctx;
ngx_http_realip_from_t *from;
ngx_http_realip_loc_conf_t *rlcf;
ctx = ngx_http_get_module_ctx(r, ngx_http_realip_module);
if (ctx) {
return NGX_DECLINED;
}
cln = ngx_pool_cleanup_add(r->pool, sizeof(ngx_http_realip_ctx_t));
if (cln == NULL) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
rlcf = ngx_http_get_module_loc_conf(r, ngx_http_realip_module);
if (rlcf->from == NULL) {
return NGX_DECLINED;
}
switch (rlcf->type) {
case NGX_HTTP_REALIP_XREALIP:
if (r->headers_in.x_real_ip == NULL) {
return NGX_DECLINED;
}
len = r->headers_in.x_real_ip->value.len;
ip = r->headers_in.x_real_ip->value.data;
break;
case NGX_HTTP_REALIP_XFWD:
if (r->headers_in.x_forwarded_for == NULL) {
return NGX_DECLINED;
}
len = r->headers_in.x_forwarded_for->value.len;
ip = r->headers_in.x_forwarded_for->value.data;
for (p = ip + len - 1; p > ip; p--) {
if (*p == ' ' || *p == ',') {
p++;
len -= p - ip;
ip = p;
break;
}
}
break;
default: /* NGX_HTTP_REALIP_HEADER */
part = &r->headers_in.headers.part;
header = part->elts;
hash = rlcf->hash;
len = rlcf->header.len;
p = rlcf->header.data;
for (i = 0; /* void */ ; i++) {
if (i >= part->nelts) {
if (part->next == NULL) {
break;
}
part = part->next;
header = part->elts;
i = 0;
}
if (hash == header[i].hash
&& len == header[i].key.len
&& ngx_strncmp(p, header[i].lowcase_key, len) == 0)
{
len = header[i].value.len;
ip = header[i].value.data;
goto found;
}
}
return NGX_DECLINED;
}
found:
c = r->connection;
ngx_log_debug1(NGX_LOG_DEBUG_HTTP, c->log, 0, "realip: \"%s\"", ip);
/* AF_INET only */
if (r->connection->sockaddr->sa_family != AF_INET) {
return NGX_DECLINED;
}
sin = (struct sockaddr_in *) c->sockaddr;
from = rlcf->from->elts;
for (i = 0; i < rlcf->from->nelts; i++) {
ngx_log_debug3(NGX_LOG_DEBUG_HTTP, c->log, 0,
"realip: %08XD %08XD %08XD",
sin->sin_addr.s_addr, from[i].mask, from[i].addr);
if ((sin->sin_addr.s_addr & from[i].mask) == from[i].addr) {
ctx = cln->data;
ngx_http_set_ctx(r, ctx, ngx_http_realip_module);
addr = inet_addr((char *) ip);
if (addr == INADDR_NONE) {
return NGX_DECLINED;
}
p = ngx_pnalloc(c->pool, len);
if (p == NULL) {
return NGX_HTTP_INTERNAL_SERVER_ERROR;
}
ngx_memcpy(p, ip, len);
cln->handler = ngx_http_realip_cleanup;
ctx->connection = c;
ctx->addr = sin->sin_addr.s_addr;
ctx->addr_text = c->addr_text;
sin->sin_addr.s_addr = addr;
c->addr_text.len = len;
c->addr_text.data = p;
return NGX_DECLINED;
}
}
return NGX_DECLINED;
}
static void
ngx_http_realip_cleanup(void *data)
{
ngx_http_realip_ctx_t *ctx = data;
ngx_connection_t *c;
struct sockaddr_in *sin;
c = ctx->connection;
sin = (struct sockaddr_in *) c->sockaddr;
sin->sin_addr.s_addr = ctx->addr;
c->addr_text = ctx->addr_text;
}
static char *
ngx_http_realip_from(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
ngx_http_realip_loc_conf_t *rlcf = conf;
ngx_int_t rc;
ngx_str_t *value;
ngx_inet_cidr_t in_cidr;
ngx_http_realip_from_t *from;
if (rlcf->from == NULL) {
rlcf->from = ngx_array_create(cf->pool, 2,
sizeof(ngx_http_realip_from_t));
if (rlcf->from == NULL) {
return NGX_CONF_ERROR;
}
}
from = ngx_array_push(rlcf->from);
if (from == NULL) {
return NGX_CONF_ERROR;
}
value = cf->args->elts;
rc = ngx_ptocidr(&value[1], &in_cidr);
if (rc == NGX_ERROR) {
ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid parameter \"%V\"",
&value[1]);
return NGX_CONF_ERROR;
}
if (rc == NGX_DONE) {
ngx_conf_log_error(NGX_LOG_WARN, cf, 0,
"low address bits of %V are meaningless", &value[1]);
}
from->mask = in_cidr.mask;
from->addr = in_cidr.addr;
return NGX_CONF_OK;
}
static char *
ngx_http_realip(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
ngx_http_realip_loc_conf_t *rlcf = conf;
ngx_str_t *value;
value = cf->args->elts;
if (ngx_strcmp(value[1].data, "X-Real-IP") == 0) {
rlcf->type = NGX_HTTP_REALIP_XREALIP;
return NGX_CONF_OK;
}
if (ngx_strcmp(value[1].data, "X-Forwarded-For") == 0) {
rlcf->type = NGX_HTTP_REALIP_XFWD;
return NGX_CONF_OK;
}
rlcf->type = NGX_HTTP_REALIP_HEADER;
rlcf->hash = ngx_hash_strlow(value[1].data, value[1].data, value[1].len);
rlcf->header = value[1];
return NGX_CONF_OK;
}
static void *
ngx_http_realip_create_loc_conf(ngx_conf_t *cf)
{
ngx_http_realip_loc_conf_t *conf;
conf = ngx_pcalloc(cf->pool, sizeof(ngx_http_realip_loc_conf_t));
if (conf == NULL) {
return NGX_CONF_ERROR;
}
/*
* set by ngx_pcalloc():
*
* conf->from = NULL;
* conf->hash = 0;
* conf->header = { 0, NULL };
*/
conf->type = NGX_CONF_UNSET_UINT;
return conf;
}
static char *
ngx_http_realip_merge_loc_conf(ngx_conf_t *cf, void *parent, void *child)
{
ngx_http_realip_loc_conf_t *prev = parent;
ngx_http_realip_loc_conf_t *conf = child;
if (conf->from == NULL) {
conf->from = prev->from;
}
ngx_conf_merge_uint_value(conf->type, prev->type, NGX_HTTP_REALIP_XREALIP);
if (conf->header.len == 0) {
conf->hash = prev->hash;
conf->header = prev->header;
}
return NGX_CONF_OK;
}
static ngx_int_t
ngx_http_realip_init(ngx_conf_t *cf)
{
ngx_http_handler_pt *h;
ngx_http_core_main_conf_t *cmcf;
cmcf = ngx_http_conf_get_module_main_conf(cf, ngx_http_core_module);
h = ngx_array_push(&cmcf->phases[NGX_HTTP_POST_READ_PHASE].handlers);
if (h == NULL) {
return NGX_ERROR;
}
*h = ngx_http_realip_handler;
h = ngx_array_push(&cmcf->phases[NGX_HTTP_PREACCESS_PHASE].handlers);
if (h == NULL) {
return NGX_ERROR;
}
*h = ngx_http_realip_handler;
return NGX_OK;
}