lib/nwamd/util.c

/*
 * CDDL HEADER START
 *
 * The contents of this file are subject to the terms of the
 * Common Development and Distribution License (the "License").
 * You may not use this file except in compliance with the License.
 *
 * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE
 * or http://www.opensolaris.org/os/licensing.
 * See the License for the specific language governing permissions
 * and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL HEADER in each
 * file and include the License file at usr/src/OPENSOLARIS.LICENSE.
 * If applicable, add the following below this CDDL HEADER, with the
 * fields enclosed by brackets "[]" replaced with your own identifying
 * information: Portions Copyright [yyyy] [name of copyright owner]
 *
 * CDDL HEADER END
 */

/*
 * Copyright 2008 Sun Microsystems, Inc.  All rights reserved.
 * Use is subject to license terms.
 */

/*
 * util.c contains a set of miscellaneous utility functions which:
 * - syslog(LOG_DEBUG, ...) if debugging is enabled
 * - check for an IP interface being marked running
 * - look up all flags for an IP interface
 * - start a child process
 * - schedule a timer
 * - look up the zone name
 */

#include <stdarg.h>
#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <pthread.h>
#include <string.h>
#include <stropts.h>
#include <syslog.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <spawn.h>
#include <wait.h>
#include <inetcfg.h>
#include <errno.h>
#include <zone.h>

#include "defines.h"
#include "structures.h"
#include "functions.h"
#include "variables.h"

extern char **environ;
boolean_t debug = B_FALSE;

/* PRINTFLIKE1 */
void
dprintf(const char *fmt, ...)
{
	va_list ap;
	char vbuf[1024];

	va_start(ap, fmt);
	if (debug) {
		(void) vsnprintf(vbuf, sizeof (vbuf), fmt, ap);
		syslog(LOG_DEBUG, "%d: %s", pthread_self(), vbuf);
	}
	va_end(ap);
}

uint64_t
get_ifflags(const char *name, sa_family_t family)
{
	icfg_if_t intf;
	icfg_handle_t h;
	uint64_t flags = 0;

	(void) strlcpy(intf.if_name, name, sizeof (intf.if_name));
	intf.if_protocol = family;

	if (icfg_open(&h, &intf) != ICFG_SUCCESS)
		return (0);

	if (icfg_get_flags(h, &flags) != ICFG_SUCCESS) {
		/*
		 * Interfaces can be ripped out from underneath us (for example
		 * by DHCP).  We don't want to spam the console for those.
		 */
		if (errno == ENOENT)
			dprintf("get_ifflags: icfg_get_flags failed for '%s'",
			    name);
		else
			syslog(LOG_ERR, "get_ifflags: icfg_get_flags %s af "
			    "%d: %m", name, family);
		/* just to be sure... */
		flags = 0;
	}
	icfg_close(h);

	return (flags);
}

/* This is just a work-around for CR 6745448: clear out a toxic interface */
void
zero_out_v4addr(const char *name)
{
	icfg_if_t intf;
	icfg_handle_t h;
	struct sockaddr_in sinv;
	socklen_t sinlen;
	int pfxlen;

	(void) strlcpy(intf.if_name, name, sizeof (intf.if_name));
	intf.if_protocol = AF_INET;

	if (icfg_open(&h, &intf) != ICFG_SUCCESS)
		return;

	sinlen = sizeof (sinv);
	if (icfg_get_addr(h, (struct sockaddr *)&sinv, &sinlen, &pfxlen,
	    B_FALSE) == ICFG_SUCCESS &&
	    sinv.sin_addr.s_addr != INADDR_ANY) {
		dprintf("bug workaround: clear out address %s on %s",
		    inet_ntoa(sinv.sin_addr), name);
		sinv.sin_addr.s_addr = INADDR_ANY;
		(void) icfg_set_addr(h, (const struct sockaddr *)&sinv, sinlen);
	}
	icfg_close(h);
}

/*
 *
 * This starts a child process determined by command.  If command contains a
 * slash then it is assumed to be a full path; otherwise the path is searched
 * for an executable file with the name command.  Command is also used as
 * argv[0] of the new process.  The rest of the arguments of the function
 * up to the first NULL make up pointers to arguments of the new process.
 *
 * This function returns child exit status on success and -1 on failure.
 *
 * NOTE: original_sigmask must be set before this function is called.
 */
int
start_childv(const char *command, char const * const *argv)
{
	posix_spawnattr_t attr;
	sigset_t fullset;
	int i, rc, status, n;
	pid_t pid;
	char vbuf[1024];

	vbuf[0] = 0;
	n = sizeof (vbuf);
	for (i = 1; argv[i] != NULL && n > 2; i++) {
		n -= strlcat(vbuf, " ", n);
		n -= strlcat(vbuf, argv[i], n);
	}
	if (argv[i] != NULL || n < 0)
		syslog(LOG_ERR, "start_childv can't log full arg vector");

	if ((rc = posix_spawnattr_init(&attr)) != 0) {
		dprintf("posix_spawnattr_init %d %s\n", rc, strerror(rc));
		return (-1);
	}
	(void) sigfillset(&fullset);
	if ((rc = posix_spawnattr_setsigdefault(&attr, &fullset)) != 0) {
		dprintf("setsigdefault %d %s\n", rc, strerror(rc));
		return (-1);
	}
	if ((rc = posix_spawnattr_setsigmask(&attr, &original_sigmask)) != 0) {
		dprintf("setsigmask %d %s\n", rc, strerror(rc));
		return (-1);
	}
	if ((rc = posix_spawnattr_setflags(&attr,
	    POSIX_SPAWN_SETSIGDEF|POSIX_SPAWN_SETSIGMASK)) != 0) {
		dprintf("setflags %d %s\n", rc, strerror(rc));
		return (-1);
	}

	if ((rc = posix_spawnp(&pid, command, NULL, &attr, (char * const *)argv,
	    environ)) > 0) {
		dprintf("posix_spawnp failed errno %d", rc);
		return (-1);
	}

	if ((rc = posix_spawnattr_destroy(&attr)) != 0) {
		dprintf("posix_spawn_attr_destroy %d %s\n", rc, strerror(rc));
		return (-1);
	}

	(void) waitpid(pid, &status, 0);
	if (WIFSIGNALED(status) || WIFSTOPPED(status)) {
		i = WIFSIGNALED(status) ? WTERMSIG(status) : WSTOPSIG(status);
		syslog(LOG_ERR, "'%s%s' %s with signal %d (%s)", command, vbuf,
		    (WIFSIGNALED(status) ? "terminated" : "stopped"), i,
		    strsignal(i));
		return (-2);
	} else {
		syslog(LOG_INFO, "'%s%s' completed normally: %d", command, vbuf,
		    WEXITSTATUS(status));
		return (WEXITSTATUS(status));
	}
}

int
start_child(const char *command, ...)
{
	const char **argv = NULL;
	int argv_len = 0;
	va_list ap;
	int i = 1, rc;

	va_start(ap, command);
	do {
		if (i >= argv_len) {
			void *p;

			argv_len = argv_len != 0 ? argv_len * 2 : 4;
			p = realloc(argv, sizeof (*argv)*argv_len);
			if (p != NULL) {
				argv = p;
			} else {
				syslog(LOG_ERR, "Out of memory in start_child");
				free(argv);
				return (-1);
			}
		}

		argv[i] = va_arg(ap, const char *);
	} while (argv[i++] != NULL);
	va_end(ap);
	argv[0] = command;

	rc = start_childv(command, argv);
	free(argv);

	return (rc);
}

uint32_t	timer_expire = TIMER_INFINITY;

/*
 * Schedules a SIGALRM in delay seconds, unless one is already
 * scheduled sooner.  If one is already scheduled later than
 * delay seconds from now, that one will be replaced.
 */
void
start_timer(uint32_t now, uint32_t delay)
{
	if (now + delay > timer_expire)
		return;

	timer_expire = now + delay;
	(void) alarm(delay);
}

void
lookup_zonename(char *zonename, size_t zonesize)
{
	zoneid_t zoneid = getzoneid();

	if (getzonenamebyid(zoneid, zonename, zonesize) >= 0)
		return;
	syslog(LOG_ERR, "could not determine zone name");
	(void) strlcpy(zonename, GLOBAL_ZONENAME, zonesize);
}