mongoose/examples/device-dashboard/net.c

289 lines
11 KiB
C

// Copyright (c) 2020-2022 Cesanta Software Limited
// All rights reserved
#include "mongoose.h"
#if !defined(MQTT_SERVER)
#if MG_ENABLE_MBEDTLS || MG_ENABLE_OPENSSL
#define MQTT_SERVER "mqtts://broker.hivemq.com:8883"
#else
#define MQTT_SERVER "mqtt://broker.hivemq.com:1883"
#endif
#endif
#define MQTT_PUBLISH_TOPIC "mg/my_device"
#define MQTT_SUBSCRIBE_TOPIC "mg/#"
// Certificate generation procedure:
// openssl ecparam -name prime256v1 -genkey -noout -out key.pem
// openssl req -new -key key.pem -x509 -nodes -days 3650 -out cert.pem
static const char *s_ssl_cert =
"-----BEGIN CERTIFICATE-----\n"
"MIIBCTCBsAIJAK9wbIDkHnAoMAoGCCqGSM49BAMCMA0xCzAJBgNVBAYTAklFMB4X\n"
"DTIzMDEyOTIxMjEzOFoXDTMzMDEyNjIxMjEzOFowDTELMAkGA1UEBhMCSUUwWTAT\n"
"BgcqhkjOPQIBBggqhkjOPQMBBwNCAARzSQS5OHd17lUeNI+6kp9WYu0cxuEIi/JT\n"
"jphbCmdJD1cUvhmzM9/phvJT9ka10Z9toZhgnBq0o0xfTQ4jC1vwMAoGCCqGSM49\n"
"BAMCA0gAMEUCIQCe0T2E0GOiVe9KwvIEPeX1J1J0T7TNacgR0Ya33HV9VgIgNvdn\n"
"aEWiBp1xshs4iz6WbpxrS1IHucrqkZuJLfNZGZI=\n"
"-----END CERTIFICATE-----\n";
static const char *s_ssl_key =
"-----BEGIN EC PRIVATE KEY-----\n"
"MHcCAQEEICBz3HOkQLPBDtdknqC7k1PNsWj6HfhyNB5MenfjmqiooAoGCCqGSM49\n"
"AwEHoUQDQgAEc0kEuTh3de5VHjSPupKfVmLtHMbhCIvyU46YWwpnSQ9XFL4ZszPf\n"
"6YbyU/ZGtdGfbaGYYJwatKNMX00OIwtb8A==\n"
"-----END EC PRIVATE KEY-----\n";
static time_t s_boot_timestamp = 0; // Updated by SNTP
#ifndef DISABLE_ROUTING
static struct mg_connection *s_sntp_conn = NULL; // SNTP connection
#endif
// Define a system time alternative
time_t ourtime(time_t *tp) {
time_t t = s_boot_timestamp + (time_t) (mg_millis() / 1000);
if (tp != NULL) *tp = t;
return t;
}
// Authenticated user.
// A user can be authenticated by:
// - a name:pass pair
// - a token
// When a user is shown a login screen, she enters a user:pass. If successful,
// a server returns user info which includes token. From that point on,
// client can use token for authentication. Tokens could be refreshed/changed
// on a server side, forcing clients to re-login.
struct user {
const char *name, *pass, *token;
};
// This is a configuration structure we're going to show on a dashboard
static struct config {
char *url, *pub, *sub; // MQTT settings
} s_config;
static struct mg_connection *s_mqtt = NULL; // MQTT connection
static bool s_connected = false; // MQTT connection established
// Try to update a single configuration value
static void update_config(struct mg_str *body, const char *name, char **value) {
char buf[256];
if (mg_http_get_var(body, name, buf, sizeof(buf)) > 0) {
free(*value);
*value = strdup(buf);
}
}
// Parse HTTP requests, return authenticated user or NULL
static struct user *getuser(struct mg_http_message *hm) {
// In production, make passwords strong and tokens randomly generated
// In this example, user list is kept in RAM. In production, it can
// be backed by file, database, or some other method.
static struct user users[] = {
{"admin", "pass0", "admin_token"},
{"user1", "pass1", "user1_token"},
{"user2", "pass2", "user2_token"},
{NULL, NULL, NULL},
};
char user[256], pass[256];
struct user *u;
mg_http_creds(hm, user, sizeof(user), pass, sizeof(pass));
if (user[0] != '\0' && pass[0] != '\0') {
// Both user and password is set, search by user/password
for (u = users; u->name != NULL; u++)
if (strcmp(user, u->name) == 0 && strcmp(pass, u->pass) == 0) return u;
} else if (user[0] == '\0') {
// Only password is set, search by token
for (u = users; u->name != NULL; u++)
if (strcmp(pass, u->token) == 0) return u;
}
return NULL;
}
// Notify all config watchers about the config change
static void send_notification(struct mg_mgr *mgr, const char *fmt, ...) {
struct mg_connection *c;
for (c = mgr->conns; c != NULL; c = c->next) {
if (c->data[0] == 'W') {
va_list ap;
va_start(ap, fmt);
mg_ws_vprintf(c, WEBSOCKET_OP_TEXT, fmt, &ap);
va_end(ap);
}
}
}
// Send simulated metrics data to the dashboard, for chart rendering
static void timer_metrics_fn(void *param) {
send_notification(param, "{%m:%m,%m:[%lu, %d]}", mg_print_esc, 0, "name",
mg_print_esc, 0, "metrics", mg_print_esc, 0, "data",
(unsigned long) ourtime(NULL),
10 + (int) ((double) rand() * 10 / RAND_MAX));
}
#ifndef DISABLE_ROUTING
// MQTT event handler function
static void mqtt_fn(struct mg_connection *c, int ev, void *ev_data, void *fnd) {
if (ev == MG_EV_CONNECT && mg_url_is_ssl(s_config.url)) {
struct mg_tls_opts opts = {.ca = "ca.pem",
.srvname = mg_url_host(s_config.url)};
mg_tls_init(c, &opts);
} else if (ev == MG_EV_MQTT_OPEN) {
s_connected = true;
c->is_hexdumping = 1;
struct mg_mqtt_opts sub_opts;
memset(&sub_opts, 0, sizeof(sub_opts));
sub_opts.topic = mg_str(s_config.sub);
sub_opts.qos = 2;
mg_mqtt_sub(s_mqtt, &sub_opts);
send_notification(c->mgr, "{%m:%m,%m:null}", mg_print_esc, 0, "name",
mg_print_esc, 0, "config", mg_print_esc, 0, "data");
MG_INFO(("MQTT connected, server %s", MQTT_SERVER));
} else if (ev == MG_EV_MQTT_MSG) {
struct mg_mqtt_message *mm = ev_data;
send_notification(c->mgr, "{%m:%m,%m:{%m: %m, %m: %m, %m: %d}}",
mg_print_esc, 0, "name", mg_print_esc, 0, "message",
mg_print_esc, 0, "data", mg_print_esc, 0, "topic",
mg_print_esc, (int) mm->topic.len, mm->topic.ptr,
mg_print_esc, 0, "data", mg_print_esc, (int) mm->data.len,
mm->data.ptr, mg_print_esc, 0, "qos", (int) mm->qos);
} else if (ev == MG_EV_MQTT_CMD) {
struct mg_mqtt_message *mm = (struct mg_mqtt_message *) ev_data;
MG_DEBUG(("%lu cmd %d qos %d", c->id, mm->cmd, mm->qos));
} else if (ev == MG_EV_CLOSE) {
s_mqtt = NULL;
if (s_connected) {
s_connected = false;
send_notification(c->mgr, "{%m:%m,%m:null}", mg_print_esc, 0, "name",
mg_print_esc, 0, "config", mg_print_esc, 0, "data");
}
}
(void) fnd;
}
// Keep MQTT connection open - reconnect if closed
static void timer_mqtt_fn(void *param) {
struct mg_mgr *mgr = (struct mg_mgr *) param;
if (s_mqtt == NULL) {
struct mg_mqtt_opts opts;
memset(&opts, 0, sizeof(opts));
s_mqtt = mg_mqtt_connect(mgr, s_config.url, &opts, mqtt_fn, NULL);
}
}
// SNTP connection event handler. When we get a response from an SNTP server,
// adjust s_boot_timestamp. We'll get a valid time from that point on
static void sfn(struct mg_connection *c, int ev, void *ev_data, void *fn_data) {
if (ev == MG_EV_SNTP_TIME) {
uint64_t t = *(uint64_t *) ev_data;
s_boot_timestamp = (time_t) ((t - mg_millis()) / 1000);
c->is_closing = 1;
} else if (ev == MG_EV_CLOSE) {
s_sntp_conn = NULL;
}
(void) fn_data;
}
static void timer_sntp_fn(void *param) { // SNTP timer function. Sync up time
struct mg_mgr *mgr = (struct mg_mgr *) param;
if (s_sntp_conn == NULL && s_boot_timestamp == 0) {
s_sntp_conn = mg_sntp_connect(mgr, NULL, sfn, NULL);
}
}
#endif
// HTTP request handler function
void device_dashboard_fn(struct mg_connection *c, int ev, void *ev_data,
void *fn_data) {
if (ev == MG_EV_OPEN && c->is_listening) {
mg_timer_add(c->mgr, 1000, MG_TIMER_REPEAT, timer_metrics_fn, c->mgr);
#ifndef DISABLE_ROUTING
mg_timer_add(c->mgr, 1000, MG_TIMER_REPEAT, timer_mqtt_fn, c->mgr);
mg_timer_add(c->mgr, 1000, MG_TIMER_REPEAT, timer_sntp_fn, c->mgr);
#endif
s_config.url = strdup(MQTT_SERVER);
s_config.pub = strdup(MQTT_PUBLISH_TOPIC);
s_config.sub = strdup(MQTT_SUBSCRIBE_TOPIC);
} else if (ev == MG_EV_ACCEPT && fn_data != NULL) {
struct mg_tls_opts opts = {.cert = s_ssl_cert, .certkey = s_ssl_key};
mg_tls_init(c, &opts);
} else if (ev == MG_EV_HTTP_MSG) {
struct mg_http_message *hm = (struct mg_http_message *) ev_data;
struct user *u = getuser(hm);
// MG_INFO(("%p [%.*s] auth %s", c->fd, (int) hm->uri.len, hm->uri.ptr,
// u ? u->name : "NULL"));
if (mg_http_match_uri(hm, "/api/hi")) {
mg_http_reply(c, 200, "", "hi\n"); // Testing endpoint
} else if (mg_http_match_uri(hm, "/api/debug")) {
int level = mg_json_get_long(hm->body, "$.level", MG_LL_DEBUG);
mg_log_set(level);
mg_http_reply(c, 200, "", "Debug level set to %d\n", level);
} else if (u == NULL && mg_http_match_uri(hm, "/api/#")) {
// All URIs starting with /api/ must be authenticated
mg_http_reply(c, 403, "", "Denied\n");
} else if (mg_http_match_uri(hm, "/api/config/get")) {
#ifdef DISABLE_ROUTING
mg_http_reply(c, 200, NULL, "{%m:%m,%m:%m,%m:%m}\n", mg_print_esc, 0,
"url", mg_print_esc, 0, s_config.url, mg_print_esc, 0,
"pub", mg_print_esc, 0, s_config.pub, mg_print_esc, 0,
"sub", mg_print_esc, 0, s_config.sub);
#else
mg_http_reply(c, 200, NULL, "{%m:%m,%m:%m,%m:%m,%m:%s}\n", mg_print_esc,
0, "url", mg_print_esc, 0, s_config.url, mg_print_esc, 0,
"pub", mg_print_esc, 0, s_config.pub, mg_print_esc, 0,
"sub", mg_print_esc, 0, s_config.sub, mg_print_esc, 0,
"connected", s_connected ? "true" : "false");
#endif
} else if (mg_http_match_uri(hm, "/api/config/set")) {
// Admins only
if (strcmp(u->name, "admin") == 0) {
update_config(&hm->body, "url", &s_config.url);
update_config(&hm->body, "pub", &s_config.pub);
update_config(&hm->body, "sub", &s_config.sub);
if (s_mqtt) s_mqtt->is_closing = 1; // Ask to disconnect from MQTT
send_notification(c->mgr, "{%m:%m,%m:null}", mg_print_esc, 0, "name",
mg_print_esc, 0, "config", mg_print_esc, 0, "data");
mg_http_reply(c, 200, "", "ok\n");
} else {
mg_http_reply(c, 403, "", "Denied\n");
}
} else if (mg_http_match_uri(hm, "/api/message/send")) {
char buf[256];
if (s_connected &&
mg_http_get_var(&hm->body, "message", buf, sizeof(buf)) > 0) {
struct mg_mqtt_opts pub_opts;
memset(&pub_opts, 0, sizeof(pub_opts));
pub_opts.topic = mg_str(s_config.pub);
pub_opts.message = mg_str(buf);
pub_opts.qos = 2, pub_opts.retain = false;
mg_mqtt_pub(s_mqtt, &pub_opts);
}
mg_http_reply(c, 200, "", "ok\n");
} else if (mg_http_match_uri(hm, "/api/watch")) {
c->data[0] = 'W'; // Mark ourselves as a event listener
mg_ws_upgrade(c, hm, NULL);
} else if (mg_http_match_uri(hm, "/api/login")) {
mg_http_reply(c, 200, NULL, "{%m:%m,%m:%m}\n", mg_print_esc, 0, "user",
mg_print_esc, 0, u->name, mg_print_esc, 0, "token",
mg_print_esc, 0, u->token);
} else {
struct mg_http_serve_opts opts;
memset(&opts, 0, sizeof(opts));
#if 1
opts.root_dir = "/web_root";
opts.fs = &mg_fs_packed;
#else
opts.root_dir = "web_root";
#endif
mg_http_serve_dir(c, ev_data, &opts);
}
MG_DEBUG(("%lu %.*s %.*s -> %.*s", c->id, (int) hm->method.len,
hm->method.ptr, (int) hm->uri.len, hm->uri.ptr, (int) 3,
&c->send.buf[9]));
}
}