Initial Contribution

1 files changed, 496 insertions, 0 deletions

diff --git a/configure.c b/configure.c
new file mode 100644
index 0000000..8c024f8
--- /dev/null
+++ b/configure.c
@@ -0,0 +1,496 @@
+/* 
+ * dhcpcd - DHCP client daemon
+ * Copyright 2006-2008 Roy Marples <roy@marples.name>
+ * All rights reserved
+
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ * 1. Redistributions of source code must retain the above copyright
+ *    notice, this list of conditions and the following disclaimer.
+ * 2. Redistributions in binary form must reproduce the above copyright
+ *    notice, this list of conditions and the following disclaimer in the
+ *    documentation and/or other materials provided with the distribution.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
+ * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
+ * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
+ * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
+ * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
+ * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
+ * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
+ * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
+ * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
+ * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
+ * SUCH DAMAGE.
+ */
+
+#include <sys/stat.h>
+#include <sys/wait.h>
+
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include <ctype.h>
+#include <errno.h>
+#include <signal.h>
+#include <stdlib.h>
+#include <unistd.h>
+
+#include "config.h"
+#include "common.h"
+#include "configure.h"
+#include "dhcp.h"
+#include "dhcpcd.h"
+#include "logger.h"
+#include "net.h"
+#include "signals.h"
+
+#define DEFAULT_PATH	"PATH=/usr/bin:/usr/sbin:/bin:/sbin"
+
+int
+exec_script(const struct options *options, const char *iface,
+	    const char *reason,
+	    const struct dhcp_message *dhcpn, const struct dhcp_message *dhcpo)
+{
+	char *const argv[2] = { UNCONST(options->script), NULL };
+	char **env = NULL, **ep;
+	char *path;
+	ssize_t e, elen;
+	int ret = 0;
+	pid_t pid;
+	int status = 0;
+	sigset_t full;
+	sigset_t old;
+
+	logger(LOG_DEBUG, "executing `%s'", options->script);
+
+	/* Make our env */
+	elen = 5;
+	env = xmalloc(sizeof(char *) * (elen + 1));
+	path = getenv("PATH");
+	if (path) {
+		e = strlen("PATH") + strlen(path) + 2;
+		env[0] = xmalloc(e);
+		snprintf(env[0], e, "PATH=%s", path);
+	} else
+		env[0] = xstrdup(DEFAULT_PATH);
+	e = strlen("interface") + strlen(iface) + 2;
+	env[1] = xmalloc(e);
+	snprintf(env[1], e, "interface=%s", iface);
+	e = strlen("reason") + strlen(reason) + 2;
+	env[2] = xmalloc(e);
+	snprintf(env[2], e, "reason=%s", reason);
+	e = 20;
+	env[3] = xmalloc(e);
+	snprintf(env[3], e, "pid=%d", getpid());
+	env[4] = xmalloc(e);
+	snprintf(env[4], e, "metric=%d", options->metric);
+	if (dhcpo) {
+		e = configure_env(NULL, NULL, dhcpo, options);
+		if (e > 0) {
+			env = xrealloc(env, sizeof(char *) * (elen + e + 1));
+			elen += configure_env(env + elen, "old", dhcpo, options);
+		}
+	}
+	if (dhcpn) {
+		e = configure_env(NULL, NULL, dhcpn, options);
+		if (e > 0) {
+			env = xrealloc(env, sizeof(char *) * (elen + e + 1));
+			elen += configure_env(env + elen, "new", dhcpn, options);
+		}
+	}
+	/* Add our base environment */
+	if (options->environ) {
+		e = 0;
+		while (options->environ[e++])
+			;
+		env = xrealloc(env, sizeof(char *) * (elen + e + 1));
+		e = 0;
+		while (options->environ[e]) {
+			env[elen + e] = xstrdup(options->environ[e]);
+			e++;
+		}
+		elen += e;
+	}
+	env[elen] = '\0';
+
+	/* OK, we need to block signals */
+	sigfillset(&full);
+	sigprocmask(SIG_SETMASK, &full, &old);
+
+#ifdef THERE_IS_NO_FORK
+	signal_reset();
+	pid = vfork();
+#else
+	pid = fork();
+#endif
+
+	switch (pid) {
+	case -1:
+#ifdef THERE_IS_NO_FORK
+		logger(LOG_ERR, "vfork: %s", strerror(errno));
+#else
+		logger(LOG_ERR, "fork: %s", strerror(errno));
+#endif
+		ret = -1;
+		break;
+	case 0:
+#ifndef THERE_IS_NO_FORK
+		signal_reset();
+#endif
+		sigprocmask(SIG_SETMASK, &old, NULL);
+		execve(options->script, argv, env);
+		logger(LOG_ERR, "%s: %s", options->script, strerror(errno));
+		_exit(111);
+		/* NOTREACHED */
+	}
+
+#ifdef THERE_IS_NO_FORK
+	signal_setup();
+#endif
+
+	/* Restore our signals */
+	sigprocmask(SIG_SETMASK, &old, NULL);
+
+	/* Wait for the script to finish */
+	while (waitpid(pid, &status, 0) == -1) {
+		if (errno != EINTR) {
+			logger(LOG_ERR, "waitpid: %s", strerror(errno));
+			status = -1;
+			break;
+		}
+	}
+
+	/* Cleanup */
+	ep = env;
+	while (*ep)
+		free(*ep++);
+	free(env);
+
+	return status;
+}
+
+static struct rt *
+reverse_routes(struct rt *routes)
+{
+	struct rt *rt;
+	struct rt *rtn = NULL;
+	
+	while (routes) {
+		rt = routes->next;
+		routes->next = rtn;
+		rtn = routes;
+		routes = rt;
+	}
+	return rtn;
+}
+
+static int
+delete_route(const char *iface, struct rt *rt, int metric)
+{
+	char *addr;
+	int retval;
+
+	addr = xstrdup(inet_ntoa(rt->dest));
+	logger(LOG_DEBUG, "removing route %s/%d via %s",
+			addr, inet_ntocidr(rt->net), inet_ntoa(rt->gate));
+	free(addr);
+	retval = del_route(iface, &rt->dest, &rt->net, &rt->gate, metric);
+	if (retval != 0)
+		logger(LOG_ERR," del_route: %s", strerror(errno));
+	return retval;
+
+}
+
+static int
+delete_routes(struct interface *iface, int metric)
+{
+	struct rt *rt;
+	struct rt *rtn;
+	int retval = 0;
+
+	rt = reverse_routes(iface->routes);
+	while (rt) {
+		rtn = rt->next;
+		retval += delete_route(iface->name, rt, metric);
+		free(rt);
+		rt = rtn;
+	}
+	iface->routes = NULL;
+
+	return retval;
+}
+
+static int
+in_routes(const struct rt *routes, const struct rt *rt)
+{
+	while (routes) {
+		if (routes->dest.s_addr == rt->dest.s_addr &&
+				routes->net.s_addr == rt->net.s_addr &&
+				routes->gate.s_addr == rt->gate.s_addr)
+			return 0;
+		routes = routes->next;
+	}
+	return -1;
+}
+
+static int
+configure_routes(struct interface *iface, const struct dhcp_message *dhcp,
+		 const struct options *options)
+{
+	struct rt *rt, *ort;
+	struct rt *rtn = NULL, *nr = NULL;
+	int remember;
+	int retval = 0;
+	char *addr;
+
+#ifdef THERE_IS_NO_FORK
+	char *skipp;
+	size_t skiplen;
+	int skip = 0;
+
+	free(dhcpcd_skiproutes);
+	/* We can never have more than 255 routes. So we need space
+	 * for 255 3 digit numbers and commas */
+	skiplen = 255 * 4 + 1;
+	skipp = dhcpcd_skiproutes = xmalloc(sizeof(char) * skiplen);
+	*skipp = '\0';
+#endif
+
+	ort = get_option_routes(dhcp);
+
+#ifdef ENABLE_IPV4LL_ALWAYSROUTE
+	if (options->options & DHCPCD_IPV4LL &&
+	    IN_PRIVATE(ntohl(dhcp->yiaddr)))
+	{
+		for (rt = ort; rt; rt = rt->next) {
+			/* Check if we have already got a link locale route
+			 * dished out by the DHCP server */
+			if (rt->dest.s_addr == htonl(LINKLOCAL_ADDR) &&
+			    rt->net.s_addr == htonl(LINKLOCAL_MASK))
+				break;
+			rtn = rt;
+		}
+
+		if (!rt) {
+			rt = xmalloc(sizeof(*rt));
+			rt->dest.s_addr = htonl(LINKLOCAL_ADDR);
+			rt->net.s_addr = htonl(LINKLOCAL_MASK);
+			rt->gate.s_addr = 0;
+			rt->next = NULL;
+			if (rtn)
+				rtn->next = rt;
+			else
+				ort = rt;
+		}
+	}
+#endif
+
+#ifdef THERE_IS_NO_FORK
+	if (dhcpcd_skiproutes) {
+		int i = -1;
+		char *sk, *skp, *token;
+		free_routes(iface->routes);
+		for (rt = ort; rt; rt = rt->next) {
+			i++;
+			/* Check that we did add this route or not */
+			sk = skp = xstrdup(dhcpcd_skiproutes);
+			while ((token = strsep(&skp, ","))) {
+				if (isdigit((unsigned char)*token) &&
+				    atoi(token) == i)
+					break;
+			}
+			free(sk);
+			if (token)
+				continue;
+			if (nr) {
+				rtn->next = xmalloc(sizeof(*rtn));
+				rtn = rtn->next;
+			} else {
+				nr = rtn = xmalloc(sizeof(*rtn));
+			}
+			rtn->dest.s_addr = rt->dest.s_addr;
+			rtn->net.s_addr = rt->net.s_addr;
+			rtn->gate.s_addr = rt->gate.s_addr;
+			rtn->next = NULL;
+		}
+		iface->routes = nr;
+		nr = NULL;
+
+		/* We no longer need this */
+		free(dhcpcd_skiproutes);
+		dhcpcd_skiproutes = NULL;
+	}
+#endif
+
+	/* Now remove old routes we no longer use.
+ 	 * We should do this in reverse order. */
+	iface->routes = reverse_routes(iface->routes);
+	for (rt = iface->routes; rt; rt = rt->next)
+		if (in_routes(ort, rt) != 0)
+			delete_route(iface->name, rt, options->metric);
+
+	for (rt = ort; rt; rt = rt->next) {
+		/* Don't set default routes if not asked to */
+		if (rt->dest.s_addr == 0 &&
+		    rt->net.s_addr == 0 &&
+		    !(options->options & DHCPCD_GATEWAY))
+			continue;
+
+		addr = xstrdup(inet_ntoa(rt->dest));
+		logger(LOG_DEBUG, "adding route to %s/%d via %s",
+			addr, inet_ntocidr(rt->net), inet_ntoa(rt->gate));
+		free(addr);
+		remember = add_route(iface->name, &rt->dest,
+				     &rt->net, &rt->gate,
+				     options->metric);
+		retval += remember;
+
+		/* If we failed to add the route, we may have already added it
+		   ourselves. If so, remember it again. */
+		if (remember < 0) {
+			if (errno != EEXIST)
+				logger(LOG_ERR, "add_route: %s",
+				       strerror(errno));
+			if (in_routes(iface->routes, rt) == 0)
+				remember = 1;
+		}
+
+		/* This login is split from above due to the #ifdef below */
+		if (remember >= 0) {
+			if (nr) {
+				rtn->next = xmalloc(sizeof(*rtn));
+				rtn = rtn->next;
+			} else {
+				nr = rtn = xmalloc(sizeof(*rtn));
+			}
+			rtn->dest.s_addr = rt->dest.s_addr;
+			rtn->net.s_addr = rt->net.s_addr;
+			rtn->gate.s_addr = rt->gate.s_addr;
+			rtn->next = NULL;
+		}
+#ifdef THERE_IS_NO_FORK
+		/* If we have daemonised yet we need to record which routes
+		 * we failed to add so we can skip them */
+		else if (!(options->options & DHCPCD_DAEMONISED)) {
+			/* We can never have more than 255 / 4 routes,
+			 * so 3 chars is plently */
+			printf("foo\n");
+			if (*skipp)
+				*skipp++ = ',';
+			skipp += snprintf(skipp,
+					  dhcpcd_skiproutes + skiplen - skipp,
+					  "%d", skip);
+		}
+		skip++;
+#endif
+	}
+	free_routes(ort);
+	free_routes(iface->routes);
+	iface->routes = nr;
+
+#ifdef THERE_IS_NO_FORK
+	if (dhcpcd_skiproutes) {
+		if (*dhcpcd_skiproutes)
+			*skipp = '\0';
+		else {
+			free(dhcpcd_skiproutes);
+			dhcpcd_skiproutes = NULL;
+		}
+	}
+#endif
+
+	return retval;
+}
+
+int
+configure(struct interface *iface, const char *reason,
+	  const struct dhcp_message *dhcp, const struct dhcp_message *old,
+	  const struct dhcp_lease *lease, const struct options *options,
+	  int up)
+{
+	struct in_addr addr;
+	struct in_addr net;
+	struct in_addr brd;
+#ifdef __linux__
+	struct in_addr dest;
+	struct in_addr gate;
+#endif
+
+	/* Grab our IP config */
+	if (dhcp == NULL || dhcp->yiaddr == 0)
+		up = 0;
+	else {
+		addr.s_addr = dhcp->yiaddr;
+		/* Ensure we have all the needed values */
+		if (get_option_addr(&net.s_addr, dhcp, DHCP_SUBNETMASK) == -1)
+			net.s_addr = get_netmask(addr.s_addr);
+		if (get_option_addr(&brd.s_addr, dhcp, DHCP_BROADCAST) == -1)
+			brd.s_addr = addr.s_addr | ~net.s_addr;
+	}
+
+	/* If we aren't up, then reset the interface as much as we can */
+	if (!up) {
+		/* Only reset things if we had set them before */
+		if (iface->addr.s_addr != 0) {
+			delete_routes(iface, options->metric);
+			logger(LOG_DEBUG, "deleting IP address %s/%d",
+			       inet_ntoa(iface->addr),
+			       inet_ntocidr(iface->net));
+			if (del_address(iface->name, &iface->addr,
+					&iface->net) == -1 &&
+			    errno != ENOENT) 
+				logger(LOG_ERR, "del_address: %s",
+				       strerror(errno));
+			iface->addr.s_addr = 0;
+			iface->net.s_addr = 0;
+		}
+
+		exec_script(options, iface->name, reason, NULL, old);
+		return 0;
+	}
+
+	/* This also changes netmask */
+	if (!(options->options & DHCPCD_INFORM) ||
+	    !has_address(iface->name, &addr, &net)) {
+		logger(LOG_DEBUG, "adding IP address %s/%d",
+		       inet_ntoa(addr), inet_ntocidr(net));
+		if (add_address(iface->name, &addr, &net, &brd) == -1 &&
+		    errno != EEXIST)
+		{
+			logger(LOG_ERR, "add_address: %s", strerror(errno));
+			return -1;
+		}
+	}
+
+	/* Now delete the old address if different */
+	if (iface->addr.s_addr != addr.s_addr &&
+	    iface->addr.s_addr != 0) 
+		del_address(iface->name, &iface->addr, &iface->net);
+
+#ifdef __linux__
+	/* On linux, we need to change the subnet route to have our metric. */
+	if (iface->addr.s_addr != lease->addr.s_addr &&
+	    options->metric > 0 && net.s_addr != INADDR_BROADCAST)
+	{
+		dest.s_addr = addr.s_addr & net.s_addr;
+		gate.s_addr = 0;
+		add_route(iface->name, &dest, &net, &gate, options->metric);
+		del_route(iface->name, &dest, &net, &gate, 0);
+	}
+#endif
+
+	configure_routes(iface, dhcp, options);
+	up = (iface->addr.s_addr != addr.s_addr ||
+	      iface->net.s_addr != net.s_addr);
+	iface->addr.s_addr = addr.s_addr;
+	iface->net.s_addr = net.s_addr;
+
+	if (!lease->frominfo)
+		if (write_lease(iface, dhcp) == -1)
+			logger(LOG_ERR, "write_lease: %s", strerror(errno));
+
+	exec_script(options, iface->name, reason, dhcp, old);
+	return 0;
+}