From 4a830b3d444af976d81ccbba4711a9e8664ec93b Mon Sep 17 00:00:00 2001
From: Guillem Jover <gjover@sipwise.com>
Date: Tue, 6 Feb 2018 18:07:05 +0100
Subject: [PATCH] TT#32302 Implement config file parsing

We need a new configuration file for multiple reasons. For security
purposes, to avoid passing passwords as part of the program arguments,
which are publicly visible. And to be able to use systemd services
files, because there's at least the maintenance configuration that's set
conditionally, and that's not easily supported in systemd service files.

Refactor the code to make it easier to add a simple config file parser,
based on a key or key=value per line, with support for comments starting
with # on the first column.

In addition this also gives us long command-line options for the
existing short options.

Change-Id: I611f262847fa2ec4e3c569ca27e01b691e585fcc
---
 config.c   | 388 ++++++++++++++++++++++++++++++++++++++++-------------
 config.h   |   2 +-
 mediator.c |   2 +-
 mediator.h |   1 +
 4 files changed, 297 insertions(+), 96 deletions(-)

diff --git a/config.c b/config.c
index 8e6138a..5930a7d 100644
--- a/config.c
+++ b/config.c
@@ -1,8 +1,10 @@
+#include <ctype.h>
 #include <getopt.h>
 
 #include "config.h"
 #include "mediator.h"
 
+char *config_file_path;
 unsigned int config_interval = MEDIATOR_DEFAULT_INTERVAL;
 uint8_t config_dumpcdr = MEDIATOR_DEFAULT_DUMPCDR;
 uint8_t config_daemonize = MEDIATOR_DEFAULT_DAEMONIZE;
@@ -36,39 +38,108 @@ med_stats_period_t config_stats_period = MEDIATOR_DEFAULT_STATSPERIOD;
 int config_maintenance = 0;
 int strict_leg_tokens = 0;
 
+enum config_option {
+	OPT_CONFIGFILE = 'c',
+	OPT_DAEMONIZE = 'd',
+	OPT_PIDFILE = 'D',
+	OPT_SYSLOG = 'l',
+	OPT_INTERVAL = 'i',
+	OPT_MED_HOST = 'h',
+	OPT_MED_PORT = 'o',
+	OPT_MED_USER = 'u',
+	OPT_MED_PASS = 'p',
+	OPT_MED_DB = 'b',
+	OPT_CDR_HOST = 'H',
+	OPT_CDR_PORT = 'O',
+	OPT_CDR_USER = 'U',
+	OPT_CDR_PASS = 'P',
+	OPT_CDR_DB = 'B',
+	OPT_PROV_HOST = 'S',
+	OPT_PROV_PORT = 'T',
+	OPT_PROV_USER = 'R',
+	OPT_PROV_PASS = 'A',
+	OPT_PROV_DB = 'N',
+	OPT_STATS_HOST = 'Z',
+	OPT_STATS_PORT = 'z',
+	OPT_STATS_USER = 'W',
+	OPT_STATS_PASS = 'w',
+	OPT_STATS_DB = 'X',
+	OPT_STATS_PERIOD = 'x',
+	OPT_MAINTENANCE = 'm',
+	OPT_LEG_TOKENS = 's',
+};
+
+static const char options[] = "?c:D:i:dlh:u:p:b:o:H:U:P:B:O:S:T:R:A:N:Z:z:W:w:X:x:ms";
+
+struct option long_options[] = {
+	{ "configfile", required_argument, NULL, OPT_CONFIGFILE },
+	{ "pidfile", required_argument, NULL, OPT_PIDFILE },
+	{ "daemonize", no_argument, NULL, OPT_DAEMONIZE },
+	{ "syslog", no_argument, NULL, OPT_SYSLOG },
+	{ "interval", required_argument, NULL, OPT_INTERVAL },
+	{ "med-host", required_argument, NULL, OPT_MED_HOST },
+	{ "med-port", required_argument, NULL, OPT_MED_PORT },
+	{ "med-user", required_argument, NULL, OPT_MED_USER },
+	{ "med-pass", required_argument, NULL, OPT_MED_PASS },
+	{ "med-db", required_argument, NULL, OPT_MED_DB },
+	{ "cdr-host", required_argument, NULL, OPT_CDR_HOST },
+	{ "cdr-port", required_argument, NULL, OPT_CDR_PORT },
+	{ "cdr-user", required_argument, NULL, OPT_CDR_USER },
+	{ "cdr-pass", required_argument, NULL, OPT_CDR_PASS },
+	{ "cdr-db", required_argument, NULL, OPT_CDR_DB },
+	{ "prov-host", required_argument, NULL, OPT_PROV_HOST },
+	{ "prov-port", required_argument, NULL, OPT_PROV_PORT },
+	{ "prov-user", required_argument, NULL, OPT_PROV_USER },
+	{ "prov-pass", required_argument, NULL, OPT_PROV_PASS },
+	{ "prov-db", required_argument, NULL, OPT_PROV_DB },
+	{ "stats-host", required_argument, NULL, OPT_STATS_HOST },
+	{ "stats-port", required_argument, NULL, OPT_STATS_PORT },
+	{ "stats-user", required_argument, NULL, OPT_STATS_USER },
+	{ "stats-pass", required_argument, NULL, OPT_STATS_PASS },
+	{ "stats-db", required_argument, NULL, OPT_STATS_DB },
+	{ "stats-period", required_argument, NULL, OPT_STATS_PERIOD },
+	{ "maintenance", no_argument, NULL, OPT_MAINTENANCE },
+	{ "leg-tokens", no_argument, NULL, OPT_LEG_TOKENS },
+	{ NULL, 0, NULL, 0 },
+};
+
 static void config_help(const char *self, int rc)
 {
-	printf("mediator %s - Creates call detail records from OpenSER accounting.\n" \
-		"Usage: %s [-?] [-d] [-D pidpath]\n" \
-		"  -D\tThe path of the PID file (default = '%s').\n" \
-		"  -d\tEnables daemonization of the process (default = disabled).\n" \
-		"  -l\tEnables dumping of CDRs to syslog (default = disabled).\n" \
-		"  -i\tThe creation interval (default = %d).\n" \
-		"  -h\tThe ACC db host (default = '%s').\n" \
-		"  -o\tThe ACC db port (default = '%d').\n" \
-		"  -u\tThe ACC db user (default = '%s').\n" \
-		"  -p\tThe ACC db pass (default = '%s').\n" \
-		"  -b\tThe ACC db name (default = '%s').\n" \
-		"  -H\tThe CDR db host (default = '%s').\n" \
-		"  -O\tThe CDR db port (default = '%d').\n" \
-		"  -U\tThe CDR db user (default = '%s').\n" \
-		"  -P\tThe CDR db pass (default = '%s').\n" \
-		"  -B\tThe CDR db name (default = '%s').\n" \
-		"  -S\tThe prov db host (default = '%s').\n" \
-		"  -T\tThe prov db port (default = '%d').\n" \
-		"  -R\tThe prov db user (default = '%s').\n" \
-		"  -A\tThe prov db pass (default = '%s').\n" \
-		"  -N\tThe prov db name (default = '%s').\n" \
-		"  -Z\tThe stats db host (default = '%s').\n" \
-		"  -z\tThe stats db port (default = '%d').\n" \
-		"  -W\tThe stats db user (default = '%s').\n" \
-		"  -w\tThe stats db pass (default = '%s').\n" \
-		"  -X\tThe stats db name (default = '%s').\n" \
-		"  -x\tThe stats db period (default = '%d', 1=hour, 2=day, 3=month).\n" \
-		"  -m\tMaintenance mode (do nothing, just sleep).\n" \
-		"  -s\tStrict acc fields (move to trash otherwise).\n" \
-		"  -?\tDisplays this message.\n",
-		MEDIATOR_VERSION, self,
+	printf(
+"mediator %s - Creates call detail records from OpenSER accounting.\n" \
+"Usage: %s [<option>...]\n" \
+"\n" \
+"Options:\n" \
+"  -c, --configfile FILE\tThe config file to use (default = '%s').\n" \
+"  -D, --pidfile PIDFILE\tThe path of the PID file (default = '%s').\n" \
+"  -d, --daemonize\tEnables daemonization of the process (default = disabled).\n" \
+"  -l, --syslog\t\tEnables dumping of CDRs to syslog (default = disabled).\n" \
+"  -i, --interval INT\tThe creation interval (default = %d).\n" \
+"  -h, --med-host HOST\tThe ACC db host (default = '%s').\n" \
+"  -o, --med-port PORT\tThe ACC db port (default = '%d').\n" \
+"  -u, --med-user USER\tThe ACC db user (default = '%s').\n" \
+"  -p, --med-pass PASS\tThe ACC db pass (default = '%s').\n" \
+"  -b, --med-db DB\tThe ACC db name (default = '%s').\n" \
+"  -H, --cdr-host HOST\tThe CDR db host (default = '%s').\n" \
+"  -O, --cdr-port PORT\tThe CDR db port (default = '%d').\n" \
+"  -U, --cdr-user USER\tThe CDR db user (default = '%s').\n" \
+"  -P, --cdr-pass PASS\tThe CDR db pass (default = '%s').\n" \
+"  -B, --cdr-db DB\tThe CDR db name (default = '%s').\n" \
+"  -S, --prov-host HOST\tThe prov db host (default = '%s').\n" \
+"  -T, --prov-port PORT\tThe prov db port (default = '%d').\n" \
+"  -R, --prov-user USER\tThe prov db user (default = '%s').\n" \
+"  -A, --prov-pass PASS\tThe prov db pass (default = '%s').\n" \
+"  -N, --prov-db DB\tThe prov db name (default = '%s').\n" \
+"  -Z, --stats-host HOST\tThe stats db host (default = '%s').\n" \
+"  -z, --stats-port PORT\tThe stats db port (default = '%d').\n" \
+"  -W, --stats-user USER\tThe stats db user (default = '%s').\n" \
+"  -w, --stats-pass PASS\tThe stats db pass (default = '%s').\n" \
+"  -X, --stats-db DB\tThe stats db name (default = '%s').\n" \
+"  -x, --stats-period INT\tThe stats db period (default = '%d', 1=hour, 2=day, 3=month).\n" \
+"  -m, --maintenance\tMaintenance mode (do nothing, just sleep).\n" \
+"  -s, --leg-tokens\tStrict acc fields (move to trash otherwise).\n" \
+"  -?, --help\t\tDisplays this message.\n",
+		MEDIATOR_VERSION, self, MEDIATOR_DEFAULT_CONFIG_FILE,
 		MEDIATOR_DEFAULT_PIDPATH, MEDIATOR_DEFAULT_INTERVAL,
 		MEDIATOR_DEFAULT_ACCHOST, MEDIATOR_DEFAULT_ACCPORT,
 		MEDIATOR_DEFAULT_ACCUSER, MEDIATOR_DEFAULT_ACCPASS,
@@ -86,82 +157,110 @@ static void config_help(const char *self, int rc)
 	exit(rc);
 }
 
-static void config_set_string_option(char **str, char *opt)
+static void config_set_string_option(char **str, const char *opt)
 {
 	free(*str);
 	*str = strdup(opt);
 }
 
-static void config_set_string_default(char **str, char *def)
+static void config_set_string_default(char **str, const char *def)
 {
 	if (*str == NULL)
 		*str = strdup(def);
 }
 
-int config_parse_cmdopts(int argc, char **argv)
+static void config_set_option(enum config_option option, const char *value)
 {
-	int c;
-
-	while((c = getopt(argc, argv, "D:i:dl?h:u:p:b:o:H:U:P:B:O:S:T:R:A:N:Z:z:W:w:X:x:ms")) != -1)
-	{
-		if(c == '?' || c == ':')
-			config_help(argv[0], 0);
-		else if(c == 'd')
-			config_daemonize = 1;
-		else if(c == 'l')
-			config_dumpcdr = 1;
-		else if(c == 'D')
-			config_set_string_option(&config_pid_path, optarg);
-		else if(c == 'i')
-			config_interval = atoi(optarg);
-		else if(c == 'h')
-			config_set_string_option(&config_med_host, optarg);
-		else if(c == 'u')
-			config_set_string_option(&config_med_user, optarg);
-		else if(c == 'p')
-			config_set_string_option(&config_med_pass, optarg);
-		else if(c == 'b')
-			config_set_string_option(&config_med_db, optarg);
-		else if(c == 'o')
-			config_med_port = atoi(optarg);
-		else if(c == 'H')
-			config_set_string_option(&config_cdr_host, optarg);
-		else if(c == 'U')
-			config_set_string_option(&config_cdr_user, optarg);
-		else if(c == 'P')
-			config_set_string_option(&config_cdr_pass, optarg);
-		else if(c == 'B')
-			config_set_string_option(&config_cdr_db, optarg);
-		else if(c == 'O')
-			config_cdr_port = atoi(optarg);
-		else if(c == 'S')
-			config_set_string_option(&config_prov_host, optarg);
-		else if(c == 'R')
-			config_set_string_option(&config_prov_user, optarg);
-		else if(c == 'A')
-			config_set_string_option(&config_prov_pass, optarg);
-		else if(c == 'N')
-			config_set_string_option(&config_prov_db, optarg);
-		else if(c == 'T')
-			config_prov_port = atoi(optarg);
-		else if(c == 'Z')
-			config_set_string_option(&config_stats_host, optarg);
-		else if(c == 'z')
-			config_stats_port = atoi(optarg);
-		else if(c == 'W')
-			config_set_string_option(&config_stats_user, optarg);
-		else if(c == 'w')
-			config_set_string_option(&config_stats_pass, optarg);
-		else if(c == 'X')
-			config_set_string_option(&config_stats_db, optarg);
-		else if(c == 'x')
-			config_stats_period = (med_stats_period_t)atoi(optarg);
-		else if(c == 'm')
-			config_maintenance = 1;
-		else if(c == 's')
-			strict_leg_tokens = 1;
+	switch (option) {
+	case OPT_DAEMONIZE:
+		config_daemonize = 1;
+		break;
+	case OPT_SYSLOG:
+		config_dumpcdr = 1;
+		break;
+	case OPT_CONFIGFILE:
+		config_set_string_option(&config_file_path, value);
+		break;
+	case OPT_PIDFILE:
+		config_set_string_option(&config_pid_path, value);
+		break;
+	case OPT_INTERVAL:
+		config_interval = atoi(value);
+		break;
+	case OPT_MED_HOST:
+		config_set_string_option(&config_med_host, value);
+		break;
+	case OPT_MED_USER:
+		config_set_string_option(&config_med_user, value);
+		break;
+	case OPT_MED_PASS:
+		config_set_string_option(&config_med_pass, value);
+		break;
+	case OPT_MED_DB:
+		config_set_string_option(&config_med_db, value);
+		break;
+	case OPT_MED_PORT:
+		config_med_port = atoi(value);
+		break;
+	case OPT_CDR_HOST:
+		config_set_string_option(&config_cdr_host, value);
+		break;
+	case OPT_CDR_USER:
+		config_set_string_option(&config_cdr_user, value);
+		break;
+	case OPT_CDR_PASS:
+		config_set_string_option(&config_cdr_pass, value);
+		break;
+	case OPT_CDR_DB:
+		config_set_string_option(&config_cdr_db, value);
+		break;
+	case OPT_CDR_PORT:
+		config_cdr_port = atoi(value);
+		break;
+	case OPT_PROV_HOST:
+		config_set_string_option(&config_prov_host, value);
+		break;
+	case OPT_PROV_USER:
+		config_set_string_option(&config_prov_user, value);
+		break;
+	case OPT_PROV_PASS:
+		config_set_string_option(&config_prov_pass, value);
+		break;
+	case OPT_PROV_DB:
+		config_set_string_option(&config_prov_db, value);
+		break;
+	case OPT_PROV_PORT:
+		config_prov_port = atoi(value);
+		break;
+	case OPT_STATS_HOST:
+		config_set_string_option(&config_stats_host, value);
+		break;
+	case OPT_STATS_USER:
+		config_set_string_option(&config_stats_user, value);
+		break;
+	case OPT_STATS_PASS:
+		config_set_string_option(&config_stats_pass, value);
+		break;
+	case OPT_STATS_PORT:
+		config_stats_port = atoi(value);
+		break;
+	case OPT_STATS_DB:
+		config_set_string_option(&config_stats_db, value);
+		break;
+	case OPT_STATS_PERIOD:
+		config_stats_period = (med_stats_period_t)atoi(value);
+		break;
+	case OPT_MAINTENANCE:
+		config_maintenance = 1;
+		break;
+	case OPT_LEG_TOKENS:
+		strict_leg_tokens = 1;
+		break;
 	}
+}
 
+static void config_set_defaults(void)
+{
 	/* Set defaults for string values. */
 	config_set_string_default(&config_pid_path, MEDIATOR_DEFAULT_PIDPATH);
 	config_set_string_default(&config_med_host, MEDIATOR_DEFAULT_ACCHOST);
@@ -180,10 +279,111 @@ int config_parse_cmdopts(int argc, char **argv)
 	config_set_string_default(&config_stats_user, MEDIATOR_DEFAULT_STATSUSER);
 	config_set_string_default(&config_stats_pass, MEDIATOR_DEFAULT_STATSPASS);
 	config_set_string_default(&config_stats_db, MEDIATOR_DEFAULT_STATSDB);
+}
+
+static int config_parse_line(char *line)
+{
+	char *sep = line;
+	const char *value;
+	struct option *option;
+
+	for (sep = line; *sep; sep++)
+		if (isspace(*sep) || *sep == '=')
+			break;
+	for (value = sep; *value; value++)
+		if (!isspace(*value) && *value != '=')
+			break;
+	if (value != sep)
+		*sep = '\0';
+
+	for (option = long_options; option->name; option++)
+		if (strcmp(option->name, line) == 0)
+			break;
+
+	if (option->name == NULL) {
+		syslog(LOG_ERR, "No option found in config file line '%s'", line);
+		return -1;
+	}
+
+	if (option->has_arg == no_argument && *value != '\0') {
+		syslog(LOG_ERR, "Unexpected value in config file option '%s'",
+		       option->name);
+		return -1;
+	} else if (option->has_arg == required_argument && *value == '\0') {
+		syslog(LOG_ERR, "Missing value in config file option '%s'",
+		       option->name);
+		return -1;
+	}
+
+	config_set_option(option->val, value);
+
+	return 0;
+}
+
+static int config_parse_file(const char *filename)
+{
+	FILE *conffile;
+	char *line = NULL;
+	size_t len = 0;
+	ssize_t nread;
+
+	syslog(LOG_DEBUG, "Loading config file '%s'", filename);
+
+	conffile = fopen(filename, "r");
+	if (conffile == NULL) {
+		if (errno == ENOENT)
+			return 0;
+
+		syslog(LOG_ERR, "Error loading config file: %s", strerror(errno));
+		return -1;
+	}
+
+	while ((nread = getline(&line, &len, conffile)) >= 0) {
+		if (line[0] == '#')
+			continue;
+
+		if (line[nread -1] == '\n')
+			line[nread - 1] = '\0';
+
+		if (config_parse_line(line) < 0) {
+			syslog(LOG_ERR, "Error parsing config file");
+			return -1;
+		}
+	}
+
+	free(line);
+	fclose(conffile);
+
+	return 0;
+}
+
+static int config_parse_cmdopts(int argc, char **argv)
+{
+	int c;
+
+	while ((c = getopt_long(argc, argv, options, long_options, NULL)) != -1)
+	{
+		if (c == '?' || c == ':')
+			config_help(argv[0], 0);
+		else
+			config_set_option(c, optarg);
+	}
 
 	return 0;
 }
 
+int config_parse(int argc, char **argv)
+{
+	int rc = 0;
+
+	rc |= config_parse_cmdopts(argc, argv);
+	config_set_string_default(&config_file_path, MEDIATOR_DEFAULT_CONFIG_FILE);
+	rc |= config_parse_file(config_file_path);
+	config_set_defaults();
+
+	return rc;
+}
+
 void config_cleanup()
 {
 	free(config_pid_path);
diff --git a/config.h b/config.h
index a2f7cda..16958b5 100644
--- a/config.h
+++ b/config.h
@@ -39,7 +39,7 @@ extern uint8_t config_dumpcdr;
 extern int config_maintenance;
 extern int strict_leg_tokens;
 
-int config_parse_cmdopts(int argc, char **argv);
+int config_parse(int argc, char **argv);
 void config_cleanup();
 
 #endif /* _CONFIG_H */
diff --git a/mediator.c b/mediator.c
index 5287237..ecfd956 100644
--- a/mediator.c
+++ b/mediator.c
@@ -171,7 +171,7 @@ int main(int argc, char **argv)
 	signal(SIGTERM, mediator_signal);
 	signal(SIGINT, mediator_signal);
 
-	if(config_parse_cmdopts(argc, argv) == -1)
+	if (config_parse(argc, argv) == -1)
 	{
 		return -1;
 	}
diff --git a/mediator.h b/mediator.h
index e74d9ad..e9f8a93 100644
--- a/mediator.h
+++ b/mediator.h
@@ -17,6 +17,7 @@
 
 #define MEDIATOR_SYSLOG_NAME "mediator"
 #define MEDIATOR_LOCK_FILE "/var/lock/mediator.lock"
+#define MEDIATOR_DEFAULT_CONFIG_FILE "/etc/ngcp-mediator/ngcp-mediator.conf"
 #define MEDIATOR_DEFAULT_DAEMONIZE 0
 #define MEDIATOR_DEFAULT_DUMPCDR 0
 #define MEDIATOR_DEFAULT_PIDPATH "/var/run/mediator.pid"