X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udevd.c;h=58f5be94bc42c43f368e1fe9665e5f34d861ab2b;hp=811f62243eb98473d6691624dadcb2dfe67b235e;hb=4497fcbf7159975560b680fd8130adcd414d3d67;hpb=e5a5b54ab675988febeaa9cd831e21e675d5947b

diff --git a/udevd.c b/udevd.c
index 811f62243..58f5be94b 100644
--- a/udevd.c
+++ b/udevd.c
@@ -33,20 +33,22 @@
 #include <sys/socket.h>
 #include <sys/un.h>
 #include <fcntl.h>
-#include "klibc_fixups.h"
 #include <sys/sysinfo.h>
 #include <sys/stat.h>
 
 #include "list.h"
 #include "udev.h"
-#include "udev_lib.h"
 #include "udev_version.h"
+#include "udev_utils.h"
 #include "udevd.h"
 #include "logging.h"
 
+/* global variables*/
+static int udevsendsock;
+
 static int pipefds[2];
 static unsigned long long expected_seqnum = 0;
-static volatile int children_waiting;
+static volatile int sigchilds_waiting;
 static volatile int run_msg_q;
 static volatile int sig_flag;
 static int run_exec_q;
@@ -58,7 +60,7 @@ static LIST_HEAD(running_list);
 static void exec_queue_manager(void);
 static void msg_queue_manager(void);
 static void user_sighandler(void);
-static void reap_kids(void);
+static void reap_sigchilds(void);
 char *udev_bin;
 
 #ifdef LOG
@@ -87,16 +89,6 @@ static void msg_dump_queue(void)
 #endif
 }
 
-static struct hotplug_msg *msg_create(void)
-{
-	struct hotplug_msg *new_msg;
-
-	new_msg = malloc(sizeof(struct hotplug_msg));
-	if (new_msg == NULL)
-		dbg("error malloc");
-	return new_msg;
-}
-
 static void run_queue_delete(struct hotplug_msg *msg)
 {
 	list_del(&msg->list);
@@ -132,25 +124,18 @@ static void msg_queue_insert(struct hotplug_msg *msg)
 /* forks event and removes event from run queue when finished */
 static void udev_run(struct hotplug_msg *msg)
 {
+	char *const argv[] = { "udev", msg->subsystem, NULL };
 	pid_t pid;
-	char action[ACTION_SIZE];
-	char devpath[DEVPATH_SIZE];
-	char seqnum[SEQNUM_SIZE];
-	char *env[] = { action, devpath, seqnum, NULL };
-
-	snprintf(action, ACTION_SIZE-1, "ACTION=%s", msg->action);
-	action[ACTION_SIZE-1] = '\0';
-	snprintf(devpath, DEVPATH_SIZE-1, "DEVPATH=%s", msg->devpath);
-	devpath[DEVPATH_SIZE-1] = '\0';
-	sprintf(seqnum, "SEQNUM=%llu", msg->seqnum);
 
 	pid = fork();
 	switch (pid) {
 	case 0:
 		/* child */
-		execle(udev_bin, "udev", msg->subsystem, NULL, env);
+		close(udevsendsock);
+		logging_close();
+		execve(udev_bin, argv, msg->envp);
 		dbg("exec of child failed");
-		exit(1);
+		_exit(1);
 		break;
 	case -1:
 		dbg("fork of child failed");
@@ -170,14 +155,19 @@ static void udev_run(struct hotplug_msg *msg)
 static struct hotplug_msg *running_with_devpath(struct hotplug_msg *msg)
 {
 	struct hotplug_msg *loop_msg;
-	list_for_each_entry(loop_msg, &running_list, list)
-		if (strncmp(loop_msg->devpath, msg->devpath, sizeof(loop_msg->devpath)) == 0)
+	list_for_each_entry(loop_msg, &running_list, list) {
+		if (loop_msg->devpath == NULL || msg->devpath == NULL)
+			continue;
+
+		if (strcmp(loop_msg->devpath, msg->devpath) == 0)
 			return loop_msg;
+	}
+
 	return NULL;
 }
 
 /* exec queue management routine executes the events and delays events for the same devpath */
-static void exec_queue_manager()
+static void exec_queue_manager(void)
 {
 	struct hotplug_msg *loop_msg;
 	struct hotplug_msg *tmp_msg;
@@ -207,7 +197,7 @@ static void msg_move_exec(struct hotplug_msg *msg)
 }
 
 /* msg queue management routine handles the timeouts and dispatches the events */
-static void msg_queue_manager()
+static void msg_queue_manager(void)
 {
 	struct hotplug_msg *loop_msg;
 	struct hotplug_msg *tmp_msg;
@@ -241,29 +231,28 @@ recheck:
 	if (list_empty(&msg_list) == 0) {
 		struct itimerval itv = {{0, 0}, {EVENT_TIMEOUT_SEC - msg_age, 0}};
 		dbg("next event expires in %li seconds", EVENT_TIMEOUT_SEC - msg_age);
-		setitimer(ITIMER_REAL, &itv, 0);
+		setitimer(ITIMER_REAL, &itv, NULL);
 	}
 }
 
 /* receive the msg, do some basic sanity checks, and queue it */
-static void handle_msg(int sock)
+static void handle_udevsend_msg(int sock)
 {
+	static struct udevsend_msg usend_msg;
 	struct hotplug_msg *msg;
-	int retval;
+	int bufpos;
+	int i;
+	ssize_t size;
 	struct msghdr smsg;
 	struct cmsghdr *cmsg;
 	struct iovec iov;
 	struct ucred *cred;
 	char cred_msg[CMSG_SPACE(sizeof(struct ucred))];
+	int envbuf_size;
 
-	msg = msg_create();
-	if (msg == NULL) {
-		dbg("unable to store message");
-		return;
-	}
-
-	iov.iov_base = msg;
-	iov.iov_len = sizeof(struct hotplug_msg);
+	memset(&usend_msg, 0x00, sizeof(struct udevsend_msg));
+	iov.iov_base = &usend_msg;
+	iov.iov_len = sizeof(struct udevsend_msg);
 
 	memset(&smsg, 0x00, sizeof(struct msghdr));
 	smsg.msg_iov = &iov;
@@ -271,8 +260,8 @@ static void handle_msg(int sock)
 	smsg.msg_control = cred_msg;
 	smsg.msg_controllen = sizeof(cred_msg);
 
-	retval = recvmsg(sock, &smsg, 0);
-	if (retval <  0) {
+	size = recvmsg(sock, &smsg, 0);
+	if (size <  0) {
 		if (errno != EINTR)
 			dbg("unable to receive message");
 		return;
@@ -282,18 +271,52 @@ static void handle_msg(int sock)
 
 	if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) {
 		dbg("no sender credentials received, message ignored");
-		goto skip;
+		goto exit;
 	}
 
 	if (cred->uid != 0) {
 		dbg("sender uid=%i, message ignored", cred->uid);
-		goto skip;
+		goto exit;
+	}
+
+	if (strncmp(usend_msg.magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
+		dbg("message magic '%s' doesn't match, ignore it", usend_msg.magic);
+		goto exit;
 	}
 
-	if (strncmp(msg->magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) {
-		dbg("message magic '%s' doesn't match, ignore it", msg->magic);
-		goto skip;
+	envbuf_size = size - offsetof(struct udevsend_msg, envbuf);
+	dbg("envbuf_size=%i", envbuf_size);
+	msg = malloc(sizeof(struct hotplug_msg) + envbuf_size);
+	memset(msg, 0x00, sizeof(struct hotplug_msg) + envbuf_size);
+
+	/* copy environment buffer and reconstruct envp */
+	memcpy(msg->envbuf, usend_msg.envbuf, envbuf_size);
+	bufpos = 0;
+	for (i = 0; (bufpos < envbuf_size) && (i < HOTPLUG_NUM_ENVP-2); i++) {
+		int keylen;
+		char *key;
+
+		key = &msg->envbuf[bufpos];
+		keylen = strlen(key);
+		msg->envp[i] = key;
+		bufpos += keylen + 1;
+		dbg("add '%s' to msg.envp[%i]", msg->envp[i], i);
+
+		/* remember some keys for further processing */
+		if (strncmp(key, "ACTION=", 7) == 0)
+			msg->action = &key[7];
+
+		if (strncmp(key, "DEVPATH=", 8) == 0)
+			msg->devpath = &key[8];
+
+		if (strncmp(key, "SUBSYSTEM=", 10) == 0)
+			msg->subsystem = &key[10];
+
+		if (strncmp(key, "SEQNUM=", 7) == 0)
+			msg->seqnum = strtoull(&key[7], NULL, 10);
 	}
+	msg->envp[i++] = "MANAGED_EVENT=1";
+	msg->envp[i] = NULL;
 
 	/* if no seqnum is given, we move straight to exec queue */
 	if (msg->seqnum == 0) {
@@ -302,10 +325,8 @@ static void handle_msg(int sock)
 	} else {
 		msg_queue_insert(msg);
 	}
-	return;
 
-skip:
-	free(msg);
+exit:
 	return;
 }
 
@@ -325,23 +346,18 @@ static void asmlinkage sig_handler(int signum)
 			break;
 		case SIGCHLD:
 			/* set flag, then write to pipe if needed */
-			children_waiting = 1;
+			sigchilds_waiting = 1;
 			goto do_write;
 			break;
-		default:
-			dbg("unhandled signal %d", signum);
-			return;
 	}
-	
+
 do_write:
 	/* if pipe is empty, write to pipe to force select to return
 	 * immediately when it gets called
 	 */
 	if (!sig_flag) {
 		rc = write(pipefds[1],&signum,sizeof(signum));
-		if (rc < 0)
-			dbg("unable to write to pipe");
-		else
+		if (rc >= 0)
 			sig_flag = 1;
 	}
 }
@@ -366,11 +382,10 @@ static void udev_done(int pid)
 	}
 }
 
-static void reap_kids()
+static void reap_sigchilds(void)
 {
-	/* reap all dead children */
 	while(1) {
-		int pid = waitpid(-1, 0, WNOHANG);
+		int pid = waitpid(-1, NULL, WNOHANG);
 		if ((pid == -1) || (pid == 0))
 			break;
 		udev_done(pid);
@@ -378,13 +393,13 @@ static void reap_kids()
 }
 
 /* just read everything from the pipe and clear the flag,
- * the useful flags were set in the signal handler
+ * the flags was set in the signal handler
  */
-static void user_sighandler()
+static void user_sighandler(void)
 {
 	int sig;
 	while(1) {
-		int rc = read(pipefds[0],&sig,sizeof(sig));
+		int rc = read(pipefds[0], &sig, sizeof(sig));
 		if (rc < 0)
 			break;
 
@@ -392,71 +407,72 @@ static void user_sighandler()
 	}
 }
 
-
-int main(int argc, char *argv[])
+int main(int argc, char *argv[], char *envp[])
 {
-	int ssock, maxsockplus;
+	int maxsockplus;
 	struct sockaddr_un saddr;
 	socklen_t addrlen;
 	int retval, fd;
-	const int on = 1;
+	const int feature_on = 1;
 	struct sigaction act;
 	fd_set readfds;
 
-	init_logging("udevd");
+	logging_init("udevd");
 	dbg("version %s", UDEV_VERSION);
 
 	if (getuid() != 0) {
 		dbg("need to be root, exit");
-		exit(1);
+		goto exit;
 	}
-	/* make sure we are at top of dir */
+
+	/* make sure we don't lock any path */
 	chdir("/");
-	umask( umask( 077 ) | 022 );
+	umask(umask(077) | 022);
+
 	/* Set fds to dev/null */
 	fd = open( "/dev/null", O_RDWR );
 	if ( fd < 0 ) {
 		dbg("error opening /dev/null %s", strerror(errno));
-		exit(1);
+		goto exit;
 	}
 	dup2(fd, 0);
 	dup2(fd, 1);
 	dup2(fd, 2);
 	if (fd > 2) 
 		close(fd);
-	/* Get new session id so stray signals don't come our way. */
+
+	/* become session leader */
 	setsid();
 
 	/* setup signal handler pipe */
 	retval = pipe(pipefds);
 	if (retval < 0) {
 		dbg("error getting pipes: %s", strerror(errno));
-		exit(1);
+		goto exit;
 	}
 
 	retval = fcntl(pipefds[0], F_SETFL, O_NONBLOCK);
 	if (retval < 0) {
 		dbg("error fcntl on read pipe: %s", strerror(errno));
-		exit(1);
+		goto exit;
 	}
 	retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC);
 	if (retval < 0) {
 		dbg("error fcntl on read pipe: %s", strerror(errno));
-		exit(1);
+		goto exit;
 	}
 
 	retval = fcntl(pipefds[1], F_SETFL, O_NONBLOCK);
 	if (retval < 0) {
 		dbg("error fcntl on write pipe: %s", strerror(errno));
-		exit(1);
+		goto exit;
 	}
 	retval = fcntl(pipefds[1], F_SETFD, FD_CLOEXEC);
 	if (retval < 0) {
 		dbg("error fcntl on write pipe: %s", strerror(errno));
-		exit(1);
+		goto exit;
 	}
 
-	
 	/* set signal handlers */
 	act.sa_handler = (void (*) (int))sig_handler;
 	sigemptyset(&act.sa_mask);
@@ -472,28 +488,22 @@ int main(int argc, char *argv[])
 	strcpy(&saddr.sun_path[1], UDEVD_SOCK_PATH);
 	addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path+1) + 1;
 
-	ssock = socket(AF_LOCAL, SOCK_DGRAM, 0);
-	if (ssock == -1) {
+	udevsendsock = socket(AF_LOCAL, SOCK_DGRAM, 0);
+	if (udevsendsock == -1) {
 		dbg("error getting socket, exit");
-		exit(1);
+		goto exit;
 	}
 
-	set_cloexec_flag(ssock, 1);
-
 	/* the bind takes care of ensuring only one copy running */
-	retval = bind(ssock, (struct sockaddr *) &saddr, addrlen);
+	retval = bind(udevsendsock, (struct sockaddr *) &saddr, addrlen);
 	if (retval < 0) {
 		dbg("bind failed, exit");
+		close(udevsendsock);
 		goto exit;
 	}
-	retval = fcntl(ssock, F_SETFD, FD_CLOEXEC);
-	if (retval < 0) {
-		dbg("error fcntl on ssock: %s", strerror(errno));
-		exit(1);
-	}
 
 	/* enable receiving of the sender credentials */
-	setsockopt(ssock, SOL_SOCKET, SO_PASSCRED, &on, sizeof(on));
+	setsockopt(udevsendsock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on));
 
 	/* possible override of udev binary, used for testing */
 	udev_bin = getenv("UDEV_BIN");
@@ -503,9 +513,9 @@ int main(int argc, char *argv[])
 		udev_bin = UDEV_BIN;
 
 	FD_ZERO(&readfds);
-	FD_SET(ssock, &readfds);
+	FD_SET(udevsendsock, &readfds);
 	FD_SET(pipefds[0], &readfds);
-	maxsockplus = ssock+1;
+	maxsockplus = udevsendsock+1;
 	while (1) {
 		fd_set workreadfds = readfds;
 		retval = select(maxsockplus, &workreadfds, NULL, NULL, NULL);
@@ -516,15 +526,15 @@ int main(int argc, char *argv[])
 			continue;
 		}
 
-		if (FD_ISSET(ssock, &workreadfds))
-			handle_msg(ssock);
+		if (FD_ISSET(udevsendsock, &workreadfds))
+			handle_udevsend_msg(udevsendsock);
 
 		if (FD_ISSET(pipefds[0], &workreadfds))
 			user_sighandler();
 
-		if (children_waiting) {
-			children_waiting = 0;
-			reap_kids();
+		if (sigchilds_waiting) {
+			sigchilds_waiting = 0;
+			reap_sigchilds();
 		}
 
 		if (run_msg_q) {
@@ -533,21 +543,18 @@ int main(int argc, char *argv[])
 		}
 
 		if (run_exec_q) {
-			/* this is tricky.  exec_queue_manager() loops over exec_list, and
-			 * calls running_with_devpath(), which loops over running_list. This gives
-			 * O(N*M), which can get *nasty*.  Clean up running_list before
-			 * calling exec_queue_manager().
-			 */
-			if (children_waiting) {
-				children_waiting = 0;
-				reap_kids();
+			 /* clean up running_list before calling exec_queue_manager() */
+			if (sigchilds_waiting) {
+				sigchilds_waiting = 0;
+				reap_sigchilds();
 			}
 
 			run_exec_q = 0;
 			exec_queue_manager();
 		}
 	}
+
 exit:
-	close(ssock);
-	exit(1);
+	logging_close();
+	return 1;
 }