*: remove --enable-tcp-zebra, rework ZAPI path

[mirror_frr.git] / lib / libfrr.c

/*
 * libfrr overall management functions
 *
 * Copyright (C) 2016  David Lamparter for NetDEF, Inc.
 *
 * 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.
 *
 * This program is distributed in the hope that it will be useful, but WITHOUT
 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
 * more details.
 *
 * You should have received a copy of the GNU General Public License along
 * with this program; see the file COPYING; if not, write to the Free Software
 * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA
 */

#include <zebra.h>
#include <sys/un.h>

#include "libfrr.h"
#include "getopt.h"
#include "vty.h"
#include "command.h"
#include "version.h"
#include "memory_vty.h"
#include "zclient.h"
#include "log_int.h"
#include "module.h"

DEFINE_HOOK(frr_late_init, (struct thread_master * tm), (tm))

const char frr_sysconfdir[] = SYSCONFDIR;
const char frr_vtydir[] = DAEMON_VTY_DIR;
const char frr_moduledir[] = MODULE_PATH;

char frr_protoname[256] = "NONE";
char frr_protonameinst[256] = "NONE";

char config_default[256];
char frr_zclientpath[256];
static char pidfile_default[256];
static char vtypath_default[256];

static char comb_optstr[256];
static struct option comb_lo[64];
static struct option *comb_next_lo = &comb_lo[0];
static char comb_helpstr[4096];

struct optspec {
	const char *optstr;
	const char *helpstr;
	const struct option *longopts;
};

static void opt_extend(const struct optspec *os)
{
	const struct option *lo;

	strcat(comb_optstr, os->optstr);
	strcat(comb_helpstr, os->helpstr);
	for (lo = os->longopts; lo->name; lo++)
		memcpy(comb_next_lo++, lo, sizeof(*lo));
}


#define OPTION_VTYSOCK   1000
#define OPTION_MODULEDIR 1002

static const struct option lo_always[] = {
	{"help", no_argument, NULL, 'h'},
	{"version", no_argument, NULL, 'v'},
	{"daemon", no_argument, NULL, 'd'},
	{"module", no_argument, NULL, 'M'},
	{"vty_socket", required_argument, NULL, OPTION_VTYSOCK},
	{"moduledir", required_argument, NULL, OPTION_MODULEDIR},
	{NULL}};
static const struct optspec os_always = {
	"hvdM:",
	"  -h, --help         Display this help and exit\n"
	"  -v, --version      Print program version\n"
	"  -d, --daemon       Runs in daemon mode\n"
	"  -M, --module       Load specified module\n"
	"      --vty_socket   Override vty socket path\n"
	"      --moduledir    Override modules directory\n",
	lo_always};


static const struct option lo_cfg_pid_dry[] = {
	{"pid_file", required_argument, NULL, 'i'},
	{"config_file", required_argument, NULL, 'f'},
	{"dryrun", no_argument, NULL, 'C'},
	{NULL}};
static const struct optspec os_cfg_pid_dry = {
	"f:i:C",
	"  -f, --config_file  Set configuration file name\n"
	"  -i, --pid_file     Set process identifier file name\n"
	"  -C, --dryrun       Check configuration for validity and exit\n",
	lo_cfg_pid_dry};


static const struct option lo_zclient[] = {
	{"socket", required_argument, NULL, 'z'},
	{NULL}};
static const struct optspec os_zclient = {
	"z:", "  -z, --socket       Set path of zebra socket\n", lo_zclient};


static const struct option lo_vty[] = {
	{"vty_addr", required_argument, NULL, 'A'},
	{"vty_port", required_argument, NULL, 'P'},
	{NULL}};
static const struct optspec os_vty = {
	"A:P:",
	"  -A, --vty_addr     Set vty's bind address\n"
	"  -P, --vty_port     Set vty's port number\n",
	lo_vty};


static const struct option lo_user[] = {{"user", required_argument, NULL, 'u'},
					{"group", required_argument, NULL, 'g'},
					{NULL}};
static const struct optspec os_user = {"u:g:",
				       "  -u, --user         User to run as\n"
				       "  -g, --group        Group to run as\n",
				       lo_user};


bool frr_zclient_addr(struct sockaddr_storage *sa, socklen_t *sa_len,
		      const char *path)
{
	memset(sa, 0, sizeof(*sa));

	if (!path)
		path = ZEBRA_SERV_PATH;

	if (!strncmp(path, ZAPI_TCP_PATHNAME, strlen(ZAPI_TCP_PATHNAME))) {
		int af;
		int port = ZEBRA_PORT;
		char *err = NULL;
		struct sockaddr_in *sin = NULL;
		struct sockaddr_in6 *sin6 = NULL;

		path += strlen(ZAPI_TCP_PATHNAME);

		switch (path[0]) {
		case '4':
			path++;
			af = AF_INET;
			break;
		case '6':
			path++;
			/* fallthrough */
		default:
			af = AF_INET6;
			break;
		}

		switch (path[0]) {
		case '\0':
			break;
		case ':':
			path++;
			port = strtoul(path, &err, 10);
			if (*err || !*path)
				return false;
			break;
		default:
			return false;
		}

		sa->ss_family = af;
		switch (af) {
		case AF_INET:
			sin = (struct sockaddr_in *)sa;
			sin->sin_port = htons(port);
			sin->sin_addr.s_addr = htonl(INADDR_LOOPBACK);
			*sa_len = sizeof(struct sockaddr_in);
#ifdef HAVE_STRUCT_SOCKADDR_IN_SIN_LEN
			sin->sin_len = *sa_len;
#endif
			break;
		case AF_INET6:
			sin6 = (struct sockaddr_in6 *)sa;
			sin6->sin6_port = htons(port);
			inet_pton(AF_INET6, "::1", &sin6->sin6_addr);
			*sa_len = sizeof(struct sockaddr_in6);
#ifdef SIN6_LEN
			sin6->sin6_len = *sa_len;
#endif
			break;
		}
	} else {
		/* "sun" is a #define on solaris */
		struct sockaddr_un *suna = (struct sockaddr_un *)sa;

		suna->sun_family = AF_UNIX;
		strlcpy(suna->sun_path, path, sizeof(suna->sun_path));
#ifdef HAVE_STRUCT_SOCKADDR_UN_SUN_LEN
		*sa_len = suna->sun_len = SUN_LEN(suna);
#else
		*sa_len = sizeof(suna->sun_family) + strlen(suna->sun_path);
#endif /* HAVE_STRUCT_SOCKADDR_UN_SUN_LEN */
#if 0
		/* this is left here for future reference;  Linux abstract
		 * socket namespace support can be enabled by replacing
		 * above #if 0 with #ifdef GNU_LINUX.
		 *
		 * THIS IS A SECURITY ISSUE, the abstract socket namespace
		 * does not have user/group permission control on sockets.
		 * we'd need to implement SCM_CREDENTIALS support first to
		 * check that only proper users can connect to abstract
		 * sockets. (same problem as tcp-zebra, except there is a
		 * fix with SCM_CREDENTIALS.  tcp-zebra has no such fix.)
		 */
		if (suna->sun_path[0] == '@')
			suna->sun_path[0] = '\0';
#endif
	}
	return true;
}

static struct frr_daemon_info *di = NULL;

void frr_preinit(struct frr_daemon_info *daemon, int argc, char **argv)
{
	di = daemon;

	/* basename(), opencoded. */
	char *p = strrchr(argv[0], '/');
	di->progname = p ? p + 1 : argv[0];

	umask(0027);

	opt_extend(&os_always);
	if (!(di->flags & FRR_NO_CFG_PID_DRY))
		opt_extend(&os_cfg_pid_dry);
	if (!(di->flags & FRR_NO_PRIVSEP))
		opt_extend(&os_user);
	if (!(di->flags & FRR_NO_ZCLIENT))
		opt_extend(&os_zclient);
	if (!(di->flags & FRR_NO_TCPVTY))
		opt_extend(&os_vty);

	snprintf(config_default, sizeof(config_default), "%s/%s.conf",
		 frr_sysconfdir, di->name);
	snprintf(pidfile_default, sizeof(pidfile_default), "%s/%s.pid",
		 frr_vtydir, di->name);

	strlcpy(frr_protoname, di->logname, sizeof(frr_protoname));
	strlcpy(frr_protonameinst, di->logname, sizeof(frr_protonameinst));

	strlcpy(frr_zclientpath, ZEBRA_SERV_PATH, sizeof(frr_zclientpath));
}

void frr_opt_add(const char *optstr, const struct option *longopts,
		 const char *helpstr)
{
	const struct optspec main_opts = {optstr, helpstr, longopts};
	opt_extend(&main_opts);
}

void frr_help_exit(int status)
{
	FILE *target = status ? stderr : stdout;

	if (status != 0)
		fprintf(stderr, "Invalid options.\n\n");

	if (di->printhelp)
		di->printhelp(target);
	else
		fprintf(target, "Usage: %s [OPTION...]\n\n%s%s%s\n\n%s",
			di->progname, di->proghelp, di->copyright ? "\n\n" : "",
			di->copyright ? di->copyright : "", comb_helpstr);
	fprintf(target, "\nReport bugs to %s\n", FRR_BUG_ADDRESS);
	exit(status);
}

struct option_chain {
	struct option_chain *next;
	const char *arg;
};

static struct option_chain *modules = NULL, **modnext = &modules;
static int errors = 0;

static int frr_opt(int opt)
{
	static int vty_port_set = 0;
	static int vty_addr_set = 0;
	struct option_chain *oc;
	char *err;

	switch (opt) {
	case 'h':
		frr_help_exit(0);
		break;
	case 'v':
		print_version(di->progname);
		exit(0);
		break;
	case 'd':
		di->daemon_mode = 1;
		break;
	case 'M':
		oc = XMALLOC(MTYPE_TMP, sizeof(*oc));
		oc->arg = optarg;
		oc->next = NULL;
		*modnext = oc;
		modnext = &oc->next;
		break;
	case 'i':
		if (di->flags & FRR_NO_CFG_PID_DRY)
			return 1;
		di->pid_file = optarg;
		break;
	case 'f':
		if (di->flags & FRR_NO_CFG_PID_DRY)
			return 1;
		di->config_file = optarg;
		break;
	case 'C':
		if (di->flags & FRR_NO_CFG_PID_DRY)
			return 1;
		di->dryrun = 1;
		break;
	case 'z':
		if (di->flags & FRR_NO_ZCLIENT)
			return 1;
		strlcpy(frr_zclientpath, optarg, sizeof(frr_zclientpath));
		break;
	case 'A':
		if (di->flags & FRR_NO_TCPVTY)
			return 1;
		if (vty_addr_set) {
			fprintf(stderr,
				"-A option specified more than once!\n");
			errors++;
			break;
		}
		vty_addr_set = 1;
		di->vty_addr = optarg;
		break;
	case 'P':
		if (di->flags & FRR_NO_TCPVTY)
			return 1;
		if (vty_port_set) {
			fprintf(stderr,
				"-P option specified more than once!\n");
			errors++;
			break;
		}
		vty_port_set = 1;
		di->vty_port = strtoul(optarg, &err, 0);
		if (*err || !*optarg) {
			fprintf(stderr,
				"invalid port number \"%s\" for -P option\n",
				optarg);
			errors++;
			break;
		}
		break;
	case OPTION_VTYSOCK:
		if (di->vty_sock_path) {
			fprintf(stderr,
				"--vty_socket option specified more than once!\n");
			errors++;
			break;
		}
		di->vty_sock_path = optarg;
		break;
	case OPTION_MODULEDIR:
		if (di->module_path) {
			fprintf(stderr,
				"----moduledir option specified more than once!\n");
			errors++;
			break;
		}
		di->module_path = optarg;
		break;
	case 'u':
		if (di->flags & FRR_NO_PRIVSEP)
			return 1;
		di->privs->user = optarg;
		break;
	case 'g':
		if (di->flags & FRR_NO_PRIVSEP)
			return 1;
		di->privs->group = optarg;
		break;
	default:
		return 1;
	}
	return 0;
}

int frr_getopt(int argc, char *const argv[], int *longindex)
{
	int opt;
	int lidx;

	comb_next_lo->name = NULL;

	do {
		opt = getopt_long(argc, argv, comb_optstr, comb_lo, &lidx);
		if (frr_opt(opt))
			break;
	} while (opt != -1);

	if (opt == -1 && errors)
		frr_help_exit(1);
	if (longindex)
		*longindex = lidx;
	return opt;
}

static struct thread_master *master;
struct thread_master *frr_init(void)
{
	struct option_chain *oc;
	struct frrmod_runtime *module;
	char moderr[256];
	const char *dir;
	dir = di->module_path ? di->module_path : frr_moduledir;

	srandom(time(NULL));

	if (di->instance)
		snprintf(frr_protonameinst, sizeof(frr_protonameinst), "%s[%u]",
			 di->logname, di->instance);

	openzlog(di->progname, di->logname, di->instance,
		 LOG_CONS | LOG_NDELAY | LOG_PID, LOG_DAEMON);
#if defined(HAVE_CUMULUS)
	zlog_set_level(ZLOG_DEST_SYSLOG, zlog_default->default_lvl);
#endif

	if (!frr_zclient_addr(&zclient_addr, &zclient_addr_len,
			      frr_zclientpath)) {
		fprintf(stderr, "Invalid zserv socket path: %s\n",
			frr_zclientpath);
		exit(1);
	}

	frrmod_init(di->module);
	while (modules) {
		modules = (oc = modules)->next;
		module = frrmod_load(oc->arg, dir, moderr, sizeof(moderr));
		if (!module) {
			fprintf(stderr, "%s\n", moderr);
			exit(1);
		}
		XFREE(MTYPE_TMP, oc);
	}

	zprivs_init(di->privs);

	master = thread_master_create(NULL);
	signal_init(master, di->n_signals, di->signals);

	if (di->flags & FRR_LIMITED_CLI)
		cmd_init(-1);
	else
		cmd_init(1);
	vty_init(master);
	memory_init();

	return master;
}

void frr_config_fork(void)
{
	hook_call(frr_late_init, master);

	if (di->instance) {
		snprintf(config_default, sizeof(config_default),
			 "%s/%s-%d.conf", frr_sysconfdir, di->name,
			 di->instance);
		snprintf(pidfile_default, sizeof(pidfile_default),
			 "%s/%s-%d.pid", frr_vtydir, di->name, di->instance);
	}

	vty_read_config(di->config_file, config_default);

	/* Don't start execution if we are in dry-run mode */
	if (di->dryrun)
		exit(0);

	/* Daemonize. */
	if (di->daemon_mode && daemon(0, 0) < 0) {
		zlog_err("Zebra daemon failed: %s", strerror(errno));
		exit(1);
	}

	if (!di->pid_file)
		di->pid_file = pidfile_default;
	pid_output(di->pid_file);
}

void frr_vty_serv(void)
{
	/* allow explicit override of vty_path in the future
	 * (not currently set anywhere) */
	if (!di->vty_path) {
		const char *dir;
		dir = di->vty_sock_path ? di->vty_sock_path : frr_vtydir;

		if (di->instance)
			snprintf(vtypath_default, sizeof(vtypath_default),
				 "%s/%s-%d.vty", dir, di->name, di->instance);
		else
			snprintf(vtypath_default, sizeof(vtypath_default),
				 "%s/%s.vty", dir, di->name);

		di->vty_path = vtypath_default;
	}

	vty_serv_sock(di->vty_addr, di->vty_port, di->vty_path);
}

void frr_run(struct thread_master *master)
{
	char instanceinfo[64] = "";

	frr_vty_serv();

	if (di->instance)
		snprintf(instanceinfo, sizeof(instanceinfo), "instance %u ",
			 di->instance);

	zlog_notice("%s %s starting: %svty@%d%s", di->name, FRR_VERSION,
		    instanceinfo, di->vty_port, di->startinfo);

	struct thread thread;
	while (thread_fetch(master, &thread))
		thread_call(&thread);
}