1 files changed, 321 insertions, 0 deletions

diff --git a/src/mailers.c b/src/mailers.c
new file mode 100644
index 0000000..05d5313
--- /dev/null
+++ b/src/mailers.c
@@ -0,0 +1,321 @@
+/*
+ * Mailer management.
+ *
+ * Copyright 2015 Horms Solutions Ltd, Simon Horman <horms@verge.net.au>
+ * Copyright 2020 Willy Tarreau <w@1wt.eu>
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version
+ * 2 of the License, or (at your option) any later version.
+ *
+ */
+
+#include <stdlib.h>
+
+#include <haproxy/action-t.h>
+#include <haproxy/api.h>
+#include <haproxy/check.h>
+#include <haproxy/errors.h>
+#include <haproxy/list.h>
+#include <haproxy/mailers.h>
+#include <haproxy/pool.h>
+#include <haproxy/proxy-t.h>
+#include <haproxy/server-t.h>
+#include <haproxy/task.h>
+#include <haproxy/tcpcheck.h>
+#include <haproxy/thread.h>
+#include <haproxy/time.h>
+#include <haproxy/tools.h>
+
+
+struct mailers *mailers = NULL;
+
+DECLARE_STATIC_POOL(pool_head_email_alert,   "email_alert",   sizeof(struct email_alert));
+
+/****************************** Email alerts ******************************/
+/* NOTE: It may be pertinent to use an applet to handle email alerts      */
+/*        instead of a tcp-check ruleset                                  */
+/**************************************************************************/
+void email_alert_free(struct email_alert *alert)
+{
+	struct tcpcheck_rule *rule, *back;
+
+	if (!alert)
+		return;
+
+	if (alert->rules.list) {
+		list_for_each_entry_safe(rule, back, alert->rules.list, list) {
+			LIST_DELETE(&rule->list);
+			free_tcpcheck(rule, 1);
+		}
+		free_tcpcheck_vars(&alert->rules.preset_vars);
+		ha_free(&alert->rules.list);
+	}
+	pool_free(pool_head_email_alert, alert);
+}
+
+static struct task *process_email_alert(struct task *t, void *context, unsigned int state)
+{
+	struct check        *check = context;
+	struct email_alertq *q;
+	struct email_alert  *alert;
+
+	q = container_of(check, typeof(*q), check);
+
+	HA_SPIN_LOCK(EMAIL_ALERTS_LOCK, &q->lock);
+	while (1) {
+		if (!(check->state & CHK_ST_ENABLED)) {
+			if (LIST_ISEMPTY(&q->email_alerts)) {
+				/* All alerts processed, queue the task */
+				t->expire = TICK_ETERNITY;
+				task_queue(t);
+				goto end;
+			}
+
+			alert = LIST_NEXT(&q->email_alerts, typeof(alert), list);
+			LIST_DELETE(&alert->list);
+			t->expire             = now_ms;
+			check->tcpcheck_rules = &alert->rules;
+			check->status         = HCHK_STATUS_INI;
+			check->state         |= CHK_ST_ENABLED;
+		}
+
+		process_chk(t, context, state);
+		if (check->state & CHK_ST_INPROGRESS)
+			break;
+
+		alert = container_of(check->tcpcheck_rules, typeof(*alert), rules);
+		email_alert_free(alert);
+		check->tcpcheck_rules = NULL;
+		check->server         = NULL;
+		check->state         &= ~CHK_ST_ENABLED;
+	}
+  end:
+	HA_SPIN_UNLOCK(EMAIL_ALERTS_LOCK, &q->lock);
+	return t;
+}
+
+/* Initializes mailer alerts for the proxy <p> using <mls> parameters.
+ *
+ * The function returns 1 in success case, otherwise, it returns 0 and err is
+ * filled.
+ */
+int init_email_alert(struct mailers *mls, struct proxy *p, char **err)
+{
+	struct mailer       *mailer;
+	struct email_alertq *queues;
+	const char          *err_str;
+	int                  i = 0;
+
+	if ((queues = calloc(mls->count, sizeof(*queues))) == NULL) {
+		memprintf(err, "out of memory while allocating mailer alerts queues");
+		goto fail_no_queue;
+	}
+
+	for (mailer = mls->mailer_list; mailer; i++, mailer = mailer->next) {
+		struct email_alertq *q     = &queues[i];
+		struct check        *check = &q->check;
+		struct task         *t;
+
+		LIST_INIT(&q->email_alerts);
+		HA_SPIN_INIT(&q->lock);
+		check->obj_type = OBJ_TYPE_CHECK;
+		check->inter = mls->timeout.mail;
+		check->rise = DEF_AGENT_RISETIME;
+		check->proxy = p;
+		check->fall = DEF_AGENT_FALLTIME;
+		if ((err_str = init_check(check, PR_O2_TCPCHK_CHK))) {
+			memprintf(err, "%s", err_str);
+			goto error;
+		}
+
+		check->xprt = mailer->xprt;
+		check->addr = mailer->addr;
+		check->port = get_host_port(&mailer->addr);
+
+		if ((t = task_new_anywhere()) == NULL) {
+			memprintf(err, "out of memory while allocating mailer alerts task");
+			goto error;
+		}
+
+		check->task = t;
+		t->process = process_email_alert;
+		t->context = check;
+
+		/* check this in one ms */
+		t->expire    = TICK_ETERNITY;
+		check->start = now;
+		task_queue(t);
+	}
+
+	mls->users++;
+	free(p->email_alert.mailers.name);
+	p->email_alert.mailers.m = mls;
+	p->email_alert.queues    = queues;
+	return 0;
+
+  error:
+	for (i = 0; i < mls->count; i++) {
+		struct email_alertq *q     = &queues[i];
+		struct check        *check = &q->check;
+
+		free_check(check);
+	}
+	free(queues);
+  fail_no_queue:
+	return 1;
+}
+
+static int enqueue_one_email_alert(struct proxy *p, struct server *s,
+				   struct email_alertq *q, const char *msg)
+{
+	struct email_alert   *alert;
+	struct tcpcheck_rule *tcpcheck;
+	struct check *check = &q->check;
+
+	if ((alert = pool_alloc(pool_head_email_alert)) == NULL)
+		goto error;
+	LIST_INIT(&alert->list);
+	alert->rules.flags = TCPCHK_RULES_TCP_CHK;
+	alert->rules.list = calloc(1, sizeof(*alert->rules.list));
+	if (!alert->rules.list)
+		goto error;
+	LIST_INIT(alert->rules.list);
+	LIST_INIT(&alert->rules.preset_vars); /* unused for email alerts */
+	alert->srv = s;
+
+	if ((tcpcheck = pool_zalloc(pool_head_tcpcheck_rule)) == NULL)
+		goto error;
+	tcpcheck->action       = TCPCHK_ACT_CONNECT;
+	tcpcheck->comment      = NULL;
+
+	LIST_APPEND(alert->rules.list, &tcpcheck->list);
+
+	if (!add_tcpcheck_expect_str(&alert->rules, "220 "))
+		goto error;
+
+	{
+		const char * const strs[4] = { "HELO ", p->email_alert.myhostname, "\r\n" };
+		if (!add_tcpcheck_send_strs(&alert->rules, strs))
+			goto error;
+	}
+
+	if (!add_tcpcheck_expect_str(&alert->rules, "250 "))
+		goto error;
+
+	{
+		const char * const strs[4] = { "MAIL FROM:<", p->email_alert.from, ">\r\n" };
+		if (!add_tcpcheck_send_strs(&alert->rules, strs))
+			goto error;
+	}
+
+	if (!add_tcpcheck_expect_str(&alert->rules, "250 "))
+		goto error;
+
+	{
+		const char * const strs[4] = { "RCPT TO:<", p->email_alert.to, ">\r\n" };
+		if (!add_tcpcheck_send_strs(&alert->rules, strs))
+			goto error;
+	}
+
+	if (!add_tcpcheck_expect_str(&alert->rules, "250 "))
+		goto error;
+
+	{
+		const char * const strs[2] = { "DATA\r\n" };
+		if (!add_tcpcheck_send_strs(&alert->rules, strs))
+			goto error;
+	}
+
+	if (!add_tcpcheck_expect_str(&alert->rules, "354 "))
+		goto error;
+
+	{
+		struct tm tm;
+		char datestr[48];
+		const char * const strs[18] = {
+			"From: ", p->email_alert.from, "\r\n",
+			"To: ", p->email_alert.to, "\r\n",
+			"Date: ", datestr, "\r\n",
+			"Subject: [HAProxy Alert] ", msg, "\r\n",
+			"\r\n",
+			msg, "\r\n",
+			"\r\n",
+			".\r\n",
+			NULL
+		};
+
+		get_localtime(date.tv_sec, &tm);
+
+		if (strftime(datestr, sizeof(datestr), "%a, %d %b %Y %T %z (%Z)", &tm) == 0) {
+			goto error;
+		}
+
+		if (!add_tcpcheck_send_strs(&alert->rules, strs))
+			goto error;
+	}
+
+	if (!add_tcpcheck_expect_str(&alert->rules, "250 "))
+		goto error;
+
+	{
+		const char * const strs[2] = { "QUIT\r\n" };
+		if (!add_tcpcheck_send_strs(&alert->rules, strs))
+			goto error;
+	}
+
+	if (!add_tcpcheck_expect_str(&alert->rules, "221 "))
+		goto error;
+
+	HA_SPIN_LOCK(EMAIL_ALERTS_LOCK, &q->lock);
+	task_wakeup(check->task, TASK_WOKEN_MSG);
+	LIST_APPEND(&q->email_alerts, &alert->list);
+	HA_SPIN_UNLOCK(EMAIL_ALERTS_LOCK, &q->lock);
+	return 1;
+
+error:
+	email_alert_free(alert);
+	return 0;
+}
+
+static void enqueue_email_alert(struct proxy *p, struct server *s, const char *msg)
+{
+	int i;
+	struct mailer *mailer;
+
+	for (i = 0, mailer = p->email_alert.mailers.m->mailer_list;
+	     i < p->email_alert.mailers.m->count; i++, mailer = mailer->next) {
+		if (!enqueue_one_email_alert(p, s, &p->email_alert.queues[i], msg)) {
+			ha_alert("Email alert [%s] could not be enqueued: out of memory\n", p->id);
+			return;
+		}
+	}
+
+	return;
+}
+
+/*
+ * Send email alert if configured.
+ */
+void send_email_alert(struct server *s, int level, const char *format, ...)
+{
+	va_list argp;
+	char buf[1024];
+	int len;
+	struct proxy *p = s->proxy;
+
+	if (!p->email_alert.mailers.m || level > p->email_alert.level || format == NULL)
+		return;
+
+	va_start(argp, format);
+	len = vsnprintf(buf, sizeof(buf), format, argp);
+	va_end(argp);
+
+	if (len < 0 || len >= sizeof(buf)) {
+		ha_alert("Email alert [%s] could not format message\n", p->id);
+		return;
+	}
+
+	enqueue_email_alert(p, s, buf);
+}