Initial env events impl + some rework

Makefile

@@ -8,6 +8,7 @@ CFLAGS  += -Wall -Wextra
 LDLIBS  += -pthread -lcurl
 STRIP    = strip
 VERSION  = v0.1
+OBJS     = alertik.o events.o env_events.o notifiers.o
 
 ifeq ($(LOG_FILE),yes)
 	CFLAGS += -DUSE_FILE_AS_LOG
@@ -32,7 +33,7 @@ CFLAGS += -DGIT_HASH=\"$(GIT_HASH)\"
 all: alertik Makefile
 	$(STRIP) --strip-all alertik
 
-alertik: alertik.o events.o
+alertik: $(OBJS)
 
 clean:
-	rm -f alertik.o events.o alertik
+	rm -f $(OBJS) alertik

alertik.c

@@ -19,29 +19,18 @@
 #include <netinet/in.h>
 #include <netdb.h>
 
-#include <curl/curl.h>
-
 #include "alertik.h"
 #include "events.h"
+#include "env_events.h"
+#include "notifiers.h"
 
 /* Uncomment/comment to enable/disable the following settings. */
 // #define USE_FILE_AS_LOG           /* stdout if commented. */
-// #define CURL_VERBOSE
-// #define VALIDATE_CERTS
-// #define DISABLE_NOTIFICATIONS
 
 #define FIFO_MAX    64
 #define SYSLOG_PORT 5140
 #define LOG_FILE    "log/log.txt"
 
-/* Telegram & request settings. */
-static char *TELEGRAM_BOT_TOKEN;
-static char *TELEGRAM_CHAT_ID;
-char *TELEGRAM_NICKNAME;
-
-#define CURL_USER_AGENT "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 " \
-                        "(KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36"
-
 /* Circular message buffer. */
 static struct circ_buffer {
 	int head;
@@ -56,7 +45,7 @@ static pthread_cond_t fifo_new_log_entry = PTHREAD_COND_INITIALIZER;
 
 /* Misc. */
 #define LAST_SENT_THRESHOLD_SECS 10  /* Minimum time (in secs) between two */
-static time_t time_last_sent_notify; /* notifications. */
+time_t time_last_sent_notify; /* notifications. */
 static int curr_file;
 
 //////////////////////////////// LOGGING //////////////////////////////////////
@@ -228,75 +217,6 @@ static int pop_msg_from_fifo(struct log_event *ev)
 }
 
 ///////////////////////////// MESSAGE HANDLING ////////////////////////////////
-
-/* Just to omit the print to stdout. */
-size_t libcurl_noop_cb(void *ptr, size_t size, size_t nmemb, void *data) {
-	((void)ptr);
-	((void)data);
-	return size * nmemb;
-}
-
-int send_telegram_notification(const char *msg)
-{
-	char full_request_url[4096] = {0};
-	char *escaped_msg = NULL;
-	CURLcode ret_curl;
-	CURL *hnd;
-	int ret;
-
-	ret = -1;
-
-	hnd = curl_easy_init();
-	if (!hnd) {
-		log_msg("> Unable to initialize libcurl!\n");
-		return ret;
-	}
-
-	log_msg("> Sending notification!\n");
-
-	escaped_msg = curl_easy_escape(hnd, msg, 0);
-	if (!escaped_msg) {
-		log_msg("> Unable to escape notification message...\n");
-		goto error;
-	}
-
-	snprintf(
-		full_request_url,
-		sizeof full_request_url - 1,
-		"https://api.telegram.org/bot%s/sendMessage?chat_id=%s&text=%s",
-		TELEGRAM_BOT_TOKEN, TELEGRAM_CHAT_ID, escaped_msg);
-
-	curl_easy_setopt(hnd, CURLOPT_URL, full_request_url);
-	curl_easy_setopt(hnd, CURLOPT_NOPROGRESS,    1L);
-	curl_easy_setopt(hnd, CURLOPT_USERAGENT, CURL_USER_AGENT);
-	curl_easy_setopt(hnd, CURLOPT_MAXREDIRS,     3L);
-	curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
-	curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, libcurl_noop_cb);
-#ifdef CURL_VERBOSE
-	curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
-#endif
-#ifndef VALIDATE_CERTS
-	curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
-#endif
-
-#ifndef DISABLE_NOTIFICATIONS
-	ret_curl = curl_easy_perform(hnd);
-	if (ret_curl != CURLE_OK) {
-		log_msg("> Unable to send request!\n");
-		goto error;
-	} else {
-		time_last_sent_notify = time(NULL); /* Update the time of our last sent */
-		log_msg("> Done!\n");               /* notification. */
-	}
-#endif
-
-	ret = 0;
-error:
-	curl_free(escaped_msg);
-	curl_easy_cleanup(hnd);
-	return ret;
-}
-
 static void *handle_messages(void *p)
 {
 	((void)p);
@@ -332,21 +252,12 @@ int main(void)
 
 	atexit(close_log_file);
 
-	TELEGRAM_BOT_TOKEN = getenv("TELEGRAM_BOT_TOKEN");
-	TELEGRAM_CHAT_ID   = getenv("TELEGRAM_CHAT_ID");
-	TELEGRAM_NICKNAME  = getenv("TELEGRAM_NICKNAME");
-
 #ifndef USE_FILE_AS_LOG
 	curr_file = STDOUT_FILENO;
 #endif
 
-	if (!TELEGRAM_BOT_TOKEN || !TELEGRAM_CHAT_ID || !TELEGRAM_NICKNAME) {
+	setup_notifiers();
-		panic("Unable to find env vars, please check if you have all of the "
+	init_environment_events();
-			"following set:\n"
-			"- TELEGRAM_BOT_TOKEN\n"
-			"- TELEGRAM_CHAT_ID\n"
-			"- TELEGRAM_NICKNAME\n");
-	}
 
 	log_msg(
 		"Alertik (" GIT_HASH ") (built at " __DATE__ " " __TIME__ ")\n");

alertik.h

@@ -8,6 +8,7 @@
 
 	#include <stdarg.h>
 	#include <stdlib.h>
+	#include <time.h>
 
 	#define panic_errno(s) \
 		do {\
@@ -23,7 +24,7 @@
 
 	#define MIN(a,b) (((a)<(b))?(a):(b))
 
-	extern char *TELEGRAM_NICKNAME;
+	extern time_t time_last_sent_notify;
 	extern char *get_formatted_time(time_t time, char *time_str);
 	extern void log_msg(const char *fmt, ...);
 	extern int  send_telegram_notification(const char *msg);

env_events.c

@@ -0,0 +1,131 @@
+/*
+ * Alertik: a tiny 'syslog' server & notification tool for Mikrotik routers.
+ * This is free and unencumbered software released into the public domain.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+#include "env_events.h"
+#include "alertik.h"
+#include "notifiers.h"
+
+/* Event match types. */
+#define MATCH_TYPES_LEN 2
+static const char *const match_types[] = {"substr", "regex"};
+
+/* Environment events list. */
+struct env_event env_events[MAX_ENV_EVENTS] = {0};
+
+/**
+ * Safe string-to-int routine that takes into account:
+ * - Overflow and Underflow
+ * - No undefined behavior
+ *
+ * Taken from https://stackoverflow.com/a/12923949/3594716
+ * and slightly adapted: no error classification, because
+ * I don't need to know, error is error.
+ *
+ * @param out Pointer to integer.
+ * @param s String to be converted.
+ *
+ * @return Returns 0 if success and a negative number otherwise.
+ */
+static int str2int(int *out, const char *s)
+{
+	char *end;
+	if (s[0] == '\0' || isspace(s[0]))
+		return -1;
+	errno = 0;
+
+	long l = strtol(s, &end, 10);
+
+	/* Both checks are needed because INT_MAX == LONG_MAX is possible. */
+	if (l > INT_MAX || (errno == ERANGE && l == LONG_MAX))
+		return -1;
+	if (l < INT_MIN || (errno == ERANGE && l == LONG_MIN))
+		return -1;
+	if (*end != '\0')
+		return -1;
+
+	*out = l;
+	return 0;
+}
+
+/**/
+static char *get_event_str(int ev_num, char *str)
+{
+	char *env;
+	char ev[64] = {0};
+	snprintf(ev, sizeof ev - 1, "EVENT%d_%s", ev_num, str);
+	if (!(env = getenv(ev)))
+		panic("Unable to find event for %s\n", ev);
+	return env;
+}
+
+/**/
+static int
+get_event_idx(int ev_num, char *str, const char *const *str_list, int size)
+{
+	char *env = get_event_str(ev_num, str);
+	for (int i = 0; i < size; i++) {
+		if (!strcmp(env, str_list[i]))
+			return i;
+	}
+	panic("String parameter (%s) invalid for %s\n", env, str);
+}
+
+
+
+
+
+
+
+/**/
+int init_environment_events(void)
+{
+	char *tmp;
+	int events;
+
+	tmp = getenv("ENV_EVENTS");
+	if (!tmp || (str2int(&events, tmp) < 0) || events <= 0)  {
+		log_msg("Environment events not detected, disabling...\n");
+		return (0);
+	}
+
+	if (events >= MAX_ENV_EVENTS)
+		panic("Environment events exceeds the maximum supported (%d/%d)\n",
+			events, MAX_ENV_EVENTS);
+
+	log_msg("%d environment events found, registering...\n");
+	for (int i = 0; i < events; i++) {
+		/* EVENTn_MATCH_TYPE. */
+		env_events[i].ev_match_type   = get_event_idx(i, "MATCH_TYPE",
+			match_types, MATCH_TYPES_LEN);
+		/* EVENTn_NOTIFIER. */
+		env_events[i].ev_notifier_idx = get_event_idx(i, "NOTIFIER",
+			notifiers_str, NUM_NOTIFIERS);
+		/* EVENTn_MATCH_STR. */
+		env_events[i].ev_match_str    = get_event_str(i, "MATCH_STR");
+		/* EVENTn_MASK_MSG. */
+		env_events[i].ev_mask_msg     = get_event_str(i, "MASK_MSG");
+	}
+
+	log_msg("Environment events summary:\n");
+	for (int i = 0; i < events; i++) {
+		printf(
+			"EVENT%d_MATCH_TYPE: %s\n"
+			"EVENT%d_MATCH_STR:  %s\n"
+			"EVENT%d_NOTIFIER:   %s\n"
+			"EVENT%d_MASK_MSG:   %s\n\n",
+			i, match_types[env_events[i].ev_match_type],
+			i, env_events[i].ev_match_str,
+			i, notifiers_str[env_events[i].ev_notifier_idx],
+			i, env_events[i].ev_mask_msg
+		);
+	}
+
+	return (0);
+}

env_events.h

@@ -0,0 +1,23 @@
+/*
+ * Alertik: a tiny 'syslog' server & notification tool for Mikrotik routers.
+ * This is free and unencumbered software released into the public domain.
+ */
+
+#ifndef ENV_EVENTS_H
+#define ENV_EVENTS_H
+
+	#include "events.h"
+
+	#define MAX_ENV_EVENTS  16
+
+	struct env_event {
+		int         ev_match_type;     /* whether regex or str.     */
+		int         ev_notifier_idx;   /* Telegram, Discord...      */
+		const char *ev_match_str;      /* regex str or substr here. */
+		const char *ev_mask_msg;       /* Mask message to be sent.  */
+	};
+
+	extern struct env_event env_events[MAX_ENV_EVENTS];
+	extern int init_environment_events(void);
+
+#endif /* ENV_EVENTS_H */

events.c

@@ -72,9 +72,8 @@ void handle_wifi_login_attempts(struct log_event *ev)
 	snprintf(
 		notification_message,
 		sizeof notification_message - 1,
-		"%s! %s!, there is someone trying to connect "
+		"There is someone trying to connect "
 		"to your WiFi: %s, with the mac-address: %s, at:%s",
-		TELEGRAM_NICKNAME, TELEGRAM_NICKNAME,
 		wifi_iface,
 		mac_addr,
 		get_formatted_time(ev->timestamp, time_str)

notifiers.c

@@ -0,0 +1,122 @@
+/*
+ * Alertik: a tiny 'syslog' server & notification tool for Mikrotik routers.
+ * This is free and unencumbered software released into the public domain.
+ */
+
+#include <ctype.h>
+#include <errno.h>
+#include <limits.h>
+#include <stdio.h>
+#include <string.h>
+
+#include <curl/curl.h>
+
+#include "notifiers.h"
+#include "alertik.h"
+
+/* Just to omit the print to stdout. */
+size_t libcurl_noop_cb(void *ptr, size_t size, size_t nmemb, void *data) {
+	((void)ptr);
+	((void)data);
+	return size * nmemb;
+}
+
+//////////////////////////////// TELEGRAM //////////////////////////////////////
+/* Telegram & request settings. */
+static char *telegram_bot_token;
+static char *telegram_chat_id;
+
+void setup_telegram(void)
+{
+	telegram_bot_token = getenv("TELEGRAM_BOT_TOKEN");
+	telegram_chat_id   = getenv("TELEGRAM_CHAT_ID");
+	if (!telegram_bot_token || !telegram_chat_id) {
+		panic(
+			"Unable to find env vars, please check if you have all of the "
+			"following set:\n"
+			"- TELEGRAM_BOT_TOKEN\n"
+			"- TELEGRAM_CHAT_ID\n"
+		);
+	}
+}
+
+int send_telegram_notification(const char *msg)
+{
+	char full_request_url[4096] = {0};
+	char *escaped_msg = NULL;
+	CURLcode ret_curl;
+	CURL *hnd;
+	int ret;
+
+	ret = -1;
+
+	hnd = curl_easy_init();
+	if (!hnd) {
+		log_msg("> Unable to initialize libcurl!\n");
+		return ret;
+	}
+
+	log_msg("> Sending notification!\n");
+
+	escaped_msg = curl_easy_escape(hnd, msg, 0);
+	if (!escaped_msg) {
+		log_msg("> Unable to escape notification message...\n");
+		goto error;
+	}
+
+	snprintf(
+		full_request_url,
+		sizeof full_request_url - 1,
+		"https://api.telegram.org/bot%s/sendMessage?chat_id=%s&text=%s",
+		telegram_bot_token, telegram_chat_id, escaped_msg);
+
+	curl_easy_setopt(hnd, CURLOPT_URL, full_request_url);
+	curl_easy_setopt(hnd, CURLOPT_NOPROGRESS,    1L);
+	curl_easy_setopt(hnd, CURLOPT_USERAGENT, CURL_USER_AGENT);
+	curl_easy_setopt(hnd, CURLOPT_MAXREDIRS,     3L);
+	curl_easy_setopt(hnd, CURLOPT_TCP_KEEPALIVE, 1L);
+	curl_easy_setopt(hnd, CURLOPT_WRITEFUNCTION, libcurl_noop_cb);
+#ifdef CURL_VERBOSE
+	curl_easy_setopt(hnd, CURLOPT_VERBOSE, 1L);
+#endif
+#ifndef VALIDATE_CERTS
+	curl_easy_setopt(hnd, CURLOPT_SSL_VERIFYPEER, 0L);
+#endif
+
+#ifndef DISABLE_NOTIFICATIONS
+	ret_curl = curl_easy_perform(hnd);
+	if (ret_curl != CURLE_OK) {
+		log_msg("> Unable to send request!\n");
+		goto error;
+	} else {
+		time_last_sent_notify = time(NULL); /* Update the time of our last sent */
+		log_msg("> Done!\n");               /* notification. */
+	}
+#endif
+
+	ret = 0;
+error:
+	curl_free(escaped_msg);
+	curl_easy_cleanup(hnd);
+	return ret;
+}
+////////////////////////////////// END ////////////////////////////////////////
+
+const char *const notifiers_str[] = {
+	"Telegram"
+};
+
+struct notifier notifiers[] = {
+	/* Telegram. */
+	{
+		.setup = setup_telegram,
+		.send_notification = send_telegram_notification
+	}
+};
+
+/* Global setup. */
+void setup_notifiers(void)
+{
+	for (int i = 0; i < NUM_NOTIFIERS; i++)
+		notifiers[i].setup();
+}

notifiers.h

@@ -0,0 +1,36 @@
+/*
+ * Alertik: a tiny 'syslog' server & notification tool for Mikrotik routers.
+ * This is free and unencumbered software released into the public domain.
+ */
+
+#ifndef NOTIFIERS_H
+#define NOTIFIERS_H
+
+	/* Uncomment/comment to enable/disable the following settings. */
+	// #define CURL_VERBOSE
+	// #define VALIDATE_CERTS
+	// #define DISABLE_NOTIFICATIONS
+
+	#define CURL_USER_AGENT "Mozilla/5.0 (X11; Linux x86_64) AppleWebKit/537.36 " \
+	                        "(KHTML, like Gecko) Chrome/125.0.0.0 Safari/537.36"
+
+	#define NUM_NOTIFIERS 1
+
+	/* Notifiers list, like:
+	 * - Telegram
+	 * - Slack
+	 * - Discord
+	 * - Teams
+	 */
+	extern const char *const notifiers_str[NUM_NOTIFIERS];
+
+	/* Notifier struct. */
+	struct notifier {
+		void(*setup)(void);
+		int(*send_notification)(const char *msg);
+	};
+
+	extern struct notifier notifiers[NUM_NOTIFIERS];
+	extern void setup_notifiers(void);
+
+#endif /* NOTIFIERS_H */