X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udevd.c;h=c6642f4359b890d1cb63cdf75ddff4739df52fab;hp=d807e4168d8b96b04ea939bdf661ff49ae3a4a22;hb=8b72687876747186d5f1a5a45464bf64b1a166f5;hpb=7d855c3116ec9ddab9adde96b568681930d9855b diff --git a/udevd.c b/udevd.c index d807e4168..c6642f435 100644 --- a/udevd.c +++ b/udevd.c @@ -33,23 +33,25 @@ #include #include #include -#include "klibc_fixups.h" -#ifndef __KLIBC__ #include -#endif +#include #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 int expected_seqnum = 0; -volatile static int children_waiting; -volatile static int run_msg_q; -volatile static int sig_flag; +static long startup_time; +static unsigned long long expected_seqnum = 0; +static volatile int sigchilds_waiting; +static volatile int run_msg_q; +static volatile int sig_flag; static int run_exec_q; static LIST_HEAD(msg_list); @@ -59,11 +61,10 @@ 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 -unsigned char logname[LOGNAME_SIZE]; void log_message (int level, const char *format, ...) { va_list args; @@ -75,7 +76,7 @@ void log_message (int level, const char *format, ...) #endif #define msg_dump(msg) \ - dbg("msg_dump: sequence %d, '%s', '%s', '%s'", \ + dbg("msg_dump: sequence %llu, '%s', '%s', '%s'", \ msg->seqnum, msg->action, msg->devpath, msg->subsystem); static void msg_dump_queue(void) @@ -84,20 +85,10 @@ static void msg_dump_queue(void) struct hotplug_msg *msg; list_for_each_entry(msg, &msg_list, list) - dbg("sequence %d in queue", msg->seqnum); + dbg("sequence %llu in queue", msg->seqnum); #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); @@ -122,7 +113,7 @@ static void msg_queue_insert(struct hotplug_msg *msg) msg->queue_time = info.uptime; list_add(&msg->list, &loop_msg->list); - dbg("queued message seq %d", msg->seqnum); + dbg("queued message seq %llu", msg->seqnum); /* run msg queue manager */ run_msg_q = 1; @@ -133,23 +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 *env[] = { action, devpath, NULL }; - - strcpy(action, "ACTION="); - strfieldcat(action, msg->action); - strcpy(devpath, "DEVPATH="); - strfieldcat(devpath, msg->devpath); 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"); @@ -160,23 +146,46 @@ static void udev_run(struct hotplug_msg *msg) break; default: /* get SIGCHLD in main loop */ - dbg("==> exec seq %d [%d] working at '%s'", msg->seqnum, pid, msg->devpath); + dbg("==> exec seq %llu [%d] working at '%s'", msg->seqnum, pid, msg->devpath); msg->pid = pid; } } -/* returns already running task with devpath */ +/* returns still running task for the same event sequence */ 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) - return loop_msg; + int i; + + list_for_each_entry(loop_msg, &running_list, list) { + if (loop_msg->devpath == NULL || msg->devpath == NULL) + continue; + + /* is a parent or child device event still running */ + for (i = 0; i < DEVPATH_SIZE; i++) { + if (loop_msg->devpath[i] == '\0' || msg->devpath[i] == '\0') + return loop_msg; + + if (loop_msg->devpath[i] != msg->devpath[i]) + break; + } + + /* is the physical device event still running on an add sequence */ + if (msg->physdevpath && msg->action && strcmp(msg->action, "add") == 0) + for (i = 0; i < DEVPATH_SIZE; i++) { + if (loop_msg->devpath[i] == '\0' || msg->physdevpath[i] == '\0') + return loop_msg; + + if (loop_msg->devpath[i] != msg->physdevpath[i]) + break; + } + } + return NULL; } -/* exec queue management routine executes the events and delays events for the same devpath */ -static void exec_queue_manager() +/* exec queue management routine executes the events and serializes events in the same sequence */ +static void exec_queue_manager(void) { struct hotplug_msg *loop_msg; struct hotplug_msg *tmp_msg; @@ -188,10 +197,10 @@ static void exec_queue_manager() /* move event to run list */ list_move_tail(&loop_msg->list, &running_list); udev_run(loop_msg); - dbg("moved seq %d to running list", loop_msg->seqnum); + dbg("moved seq %llu to running list", loop_msg->seqnum); } else { - dbg("delay seq %d, cause seq %d already working on '%s'", - loop_msg->seqnum, msg->seqnum, msg->devpath); + dbg("delay seq %llu (%s), cause seq %llu (%s) is still running", + loop_msg->seqnum, loop_msg->devpath, msg->seqnum, msg->devpath); } } } @@ -201,19 +210,21 @@ static void msg_move_exec(struct hotplug_msg *msg) list_move_tail(&msg->list, &exec_list); run_exec_q = 1; expected_seqnum = msg->seqnum+1; - dbg("moved seq %d to exec, next expected is %d", + dbg("moved seq %llu to exec, next expected is %llu", msg->seqnum, expected_seqnum); } /* 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; struct sysinfo info; long msg_age = 0; + static int timeout = EVENT_INIT_TIMEOUT_SEC; + static int init = 1; - dbg("msg queue manager, next expected is %d", expected_seqnum); + dbg("msg queue manager, next expected is %llu", expected_seqnum); recheck: list_for_each_entry_safe(loop_msg, tmp_msg, &msg_list, list) { /* move event with expected sequence to the exec list */ @@ -222,11 +233,18 @@ recheck: continue; } + /* see if we are in the initialization phase and wait for the very first events */ + if (init && (info.uptime - startup_time >= INIT_TIME_SEC)) { + init = 0; + timeout = EVENT_TIMEOUT_SEC; + dbg("initialization phase passed, set timeout to %i seconds", EVENT_TIMEOUT_SEC); + } + /* move event with expired timeout to the exec list */ sysinfo(&info); msg_age = info.uptime - loop_msg->queue_time; - dbg("seq %d is %li seconds old", loop_msg->seqnum, msg_age); - if (msg_age > EVENT_TIMEOUT_SEC-1) { + dbg("seq %llu is %li seconds old", loop_msg->seqnum, msg_age); + if (msg_age >= timeout) { msg_move_exec(loop_msg); goto recheck; } else { @@ -238,31 +256,30 @@ recheck: /* set timeout for remaining queued events */ 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); + struct itimerval itv = {{0, 0}, {timeout - msg_age, 0}}; + dbg("next event expires in %li seconds", timeout - msg_age); + 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; @@ -270,8 +287,8 @@ 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; @@ -281,36 +298,72 @@ 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(msg->magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) { - dbg("message magic '%s' doesn't match, ignore it", msg->magic); - goto skip; + 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; + } + + 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); + + if (strncmp(key, "PHYSDEVPATH=", 12) == 0) + msg->physdevpath = &key[12]; } + msg->envp[i++] = "UDEVD_EVENT=1"; + msg->envp[i] = NULL; /* if no seqnum is given, we move straight to exec queue */ - if (msg->seqnum == -1) { + if (msg->seqnum == 0) { list_add(&msg->list, &exec_list); run_exec_q = 1; } else { msg_queue_insert(msg); } - return; -skip: - free(msg); +exit: return; } -static void sig_handler(int signum) +static void asmlinkage sig_handler(int signum) { int rc; + switch (signum) { case SIGINT: case SIGTERM: @@ -323,23 +376,18 @@ static void 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"); - 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; } } @@ -351,9 +399,9 @@ static void udev_done(int pid) list_for_each_entry(msg, &running_list, list) { if (msg->pid == pid) { - dbg("<== exec seq %d came back", msg->seqnum); + dbg("<== exec seq %llu came back", msg->seqnum); run_queue_delete(msg); - + /* we want to run the exec queue manager since there may * be events waiting with the devpath of the one that * just finished @@ -364,11 +412,10 @@ 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); @@ -376,13 +423,13 @@ 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; @@ -390,46 +437,75 @@ static void user_sighandler() } } - -int main(int argc, char *argv[]) +int main(int argc, char *argv[], char *envp[]) { - int ssock, maxsockplus; + struct sysinfo info; + int maxsockplus; struct sockaddr_un saddr; socklen_t addrlen; - int retval; - const int on = 1; + int retval, fd; + 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 don't lock any path */ + chdir("/"); + 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)); + goto exit; } + dup2(fd, 0); + dup2(fd, 1); + dup2(fd, 2); + if (fd > 2) + close(fd); + + /* 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) { + 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)); + 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)); + goto exit; } /* set signal handlers */ - act.sa_handler = sig_handler; + act.sa_handler = (void (*) (int))sig_handler; sigemptyset(&act.sa_mask); act.sa_flags = SA_RESTART; sigaction(SIGINT, &act, NULL); @@ -443,21 +519,22 @@ 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; } /* 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; } /* 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"); @@ -466,10 +543,14 @@ int main(int argc, char *argv[]) else udev_bin = UDEV_BIN; + /* handle special startup timeout*/ + sysinfo(&info); + startup_time = info.uptime; + 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); @@ -480,15 +561,15 @@ 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) { @@ -497,21 +578,18 @@ 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; }