X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=udevd.c;h=371d71571603d5b0c3d99346e0b940067300844c;hb=1682c8c4a3909f9d80f17544bcfc6fb73379bc7e;hp=2cd3622ce011a5a04630ff8d05595dbd6d53fc81;hpb=138068d690d79e71239d3e776f01560afbabc1cb;p=elogind.git diff --git a/udevd.c b/udevd.c index 2cd3622ce..371d71571 100644 --- a/udevd.c +++ b/udevd.c @@ -38,6 +38,7 @@ #include #include #include +#include #include "list.h" #include "udev_libc_wrapper.h" @@ -48,16 +49,18 @@ #include "logging.h" /* global variables*/ -static int udevsendsock; +static int udevd_sock; +static int uevent_nl_sock; static pid_t sid; static int pipefds[2]; static long startup_time; -static unsigned long long expected_seqnum = 0; +static unsigned long long expected_seqnum; static volatile int sigchilds_waiting; static volatile int run_msg_q; static volatile int sig_flag; static int run_exec_q; +static int stop_exec_q; static LIST_HEAD(msg_list); static LIST_HEAD(exec_list); @@ -70,40 +73,39 @@ static void reap_sigchilds(void); char *udev_bin; #ifdef USE_LOG -void log_message (int level, const char *format, ...) +void log_message (int priority, const char *format, ...) { - va_list args; + va_list args; + + if (priority > udev_log_priority) + return; va_start(args, format); - vsyslog(level, format, args); + vsyslog(priority, format, args); va_end(args); } #endif -#define msg_dump(msg) \ - dbg("msg_dump: sequence %llu, '%s', '%s', '%s'", \ - msg->seqnum, msg->action, msg->devpath, msg->subsystem); - static void msg_dump_queue(void) { #ifdef DEBUG - struct hotplug_msg *msg; + struct uevent_msg *msg; list_for_each_entry(msg, &msg_list, node) dbg("sequence %llu in queue", msg->seqnum); #endif } -static void run_queue_delete(struct hotplug_msg *msg) +static void run_queue_delete(struct uevent_msg *msg) { list_del(&msg->node); free(msg); } /* orders the message in the queue by sequence number */ -static void msg_queue_insert(struct hotplug_msg *msg) +static void msg_queue_insert(struct uevent_msg *msg) { - struct hotplug_msg *loop_msg; + struct uevent_msg *loop_msg; struct sysinfo info; if (msg->seqnum == 0) { @@ -113,6 +115,14 @@ static void msg_queue_insert(struct hotplug_msg *msg) return; } + /* don't delay messages with timeout set */ + if (msg->timeout) { + dbg("move seq %llu with timeout %u to exec queue", msg->seqnum, msg->timeout); + list_add(&msg->node, &exec_list); + run_exec_q = 1; + return; + } + /* sort message by sequence number into list */ list_for_each_entry_reverse(loop_msg, &msg_list, node) { if (loop_msg->seqnum < msg->seqnum) @@ -120,6 +130,7 @@ static void msg_queue_insert(struct hotplug_msg *msg) if (loop_msg->seqnum == msg->seqnum) { dbg("ignoring duplicate message seq %llu", msg->seqnum); + free(msg); return; } } @@ -138,7 +149,7 @@ 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) +static void execute_udev(struct uevent_msg *msg) { char *const argv[] = { "udev", msg->subsystem, NULL }; pid_t pid; @@ -147,16 +158,18 @@ static void udev_run(struct hotplug_msg *msg) switch (pid) { case 0: /* child */ - close(udevsendsock); + if (uevent_nl_sock != -1) + close(uevent_nl_sock); + close(udevd_sock); logging_close(); setpriority(PRIO_PROCESS, 0, UDEV_PRIORITY); execve(udev_bin, argv, msg->envp); - dbg("exec of child failed"); + err("exec of child failed"); _exit(1); break; case -1: - dbg("fork of child failed"); + err("fork of child failed"); run_queue_delete(msg); break; default: @@ -286,13 +299,17 @@ static int compare_devpath(const char *running, const char *waiting) } /* returns still running task for the same device, its parent or its physical device */ -static struct hotplug_msg *running_with_devpath(struct hotplug_msg *msg) +static struct uevent_msg *running_with_devpath(struct uevent_msg *msg) { - struct hotplug_msg *loop_msg; + struct uevent_msg *loop_msg; if (msg->devpath == NULL) return NULL; + /* skip any events with a timeout set */ + if (msg->timeout) + return NULL; + list_for_each_entry(loop_msg, &running_list, node) { if (loop_msg->devpath == NULL) continue; @@ -313,9 +330,9 @@ static struct hotplug_msg *running_with_devpath(struct hotplug_msg *msg) /* 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; - struct hotplug_msg *msg; + struct uevent_msg *loop_msg; + struct uevent_msg *tmp_msg; + struct uevent_msg *msg; int running; running = running_processes(); @@ -338,7 +355,7 @@ static void exec_queue_manager(void) if (!msg) { /* move event to run list */ list_move_tail(&loop_msg->node, &running_list); - udev_run(loop_msg); + execute_udev(loop_msg); running++; dbg("moved seq %llu to running list", loop_msg->seqnum); } else { @@ -348,7 +365,7 @@ static void exec_queue_manager(void) } } -static void msg_move_exec(struct hotplug_msg *msg) +static void msg_move_exec(struct uevent_msg *msg) { list_move_tail(&msg->node, &exec_list); run_exec_q = 1; @@ -360,8 +377,8 @@ 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(void) { - struct hotplug_msg *loop_msg; - struct hotplug_msg *tmp_msg; + struct uevent_msg *loop_msg; + struct uevent_msg *tmp_msg; struct sysinfo info; long msg_age = 0; static int timeout = EVENT_INIT_TIMEOUT_SEC; @@ -405,13 +422,60 @@ recheck: } } -/* receive the udevsend message and do some sanity checks */ -static struct hotplug_msg *get_udevsend_msg(void) +static struct uevent_msg *get_msg_from_envbuf(const char *buf, int buf_size) { - static struct udevsend_msg usend_msg; - struct hotplug_msg *msg; int bufpos; int i; + struct uevent_msg *msg; + + msg = malloc(sizeof(struct uevent_msg) + buf_size); + if (msg == NULL) + return NULL; + memset(msg, 0x00, sizeof(struct uevent_msg) + buf_size); + + /* copy environment buffer and reconstruct envp */ + memcpy(msg->envbuf, buf, buf_size); + bufpos = 0; + for (i = 0; (bufpos < buf_size) && (i < UEVENT_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]; + + if (strncmp(key, "TIMEOUT=", 8) == 0) + msg->timeout = strtoull(&key[8], NULL, 10); + } + msg->envp[i++] = "UDEVD_EVENT=1"; + msg->envp[i] = NULL; + + return msg; +} + +/* receive the udevd message from userspace */ +static struct uevent_msg *get_udevd_msg(void) +{ + static struct udevd_msg usend_msg; + struct uevent_msg *msg; ssize_t size; struct msghdr smsg; struct cmsghdr *cmsg; @@ -420,9 +484,9 @@ static struct hotplug_msg *get_udevsend_msg(void) char cred_msg[CMSG_SPACE(sizeof(struct ucred))]; int envbuf_size; - memset(&usend_msg, 0x00, sizeof(struct udevsend_msg)); + memset(&usend_msg, 0x00, sizeof(struct udevd_msg)); iov.iov_base = &usend_msg; - iov.iov_len = sizeof(struct udevsend_msg); + iov.iov_len = sizeof(struct udevd_msg); memset(&smsg, 0x00, sizeof(struct msghdr)); smsg.msg_iov = &iov; @@ -430,69 +494,101 @@ static struct hotplug_msg *get_udevsend_msg(void) smsg.msg_control = cred_msg; smsg.msg_controllen = sizeof(cred_msg); - size = recvmsg(udevsendsock, &smsg, 0); + size = recvmsg(udevd_sock, &smsg, 0); if (size < 0) { if (errno != EINTR) - dbg("unable to receive udevsend message"); + dbg("unable to receive udevd message"); return NULL; } cmsg = CMSG_FIRSTHDR(&smsg); cred = (struct ucred *) CMSG_DATA(cmsg); if (cmsg == NULL || cmsg->cmsg_type != SCM_CREDENTIALS) { - dbg("no sender credentials received, message ignored"); + info("no sender credentials received, message ignored"); return NULL; } if (cred->uid != 0) { - dbg("sender uid=%i, message ignored", cred->uid); + info("sender uid=%i, message ignored", cred->uid); return NULL; } if (strncmp(usend_msg.magic, UDEV_MAGIC, sizeof(UDEV_MAGIC)) != 0 ) { - dbg("message magic '%s' doesn't match, ignore it", usend_msg.magic); + info("message magic '%s' doesn't match, ignore it", usend_msg.magic); return NULL; } - envbuf_size = size - offsetof(struct udevsend_msg, envbuf); - dbg("envbuf_size=%i", envbuf_size); - msg = malloc(sizeof(struct hotplug_msg) + envbuf_size); - if (msg == NULL) - return NULL; - - memset(msg, 0x00, sizeof(struct hotplug_msg) + envbuf_size); +switch (usend_msg.type) { + case UDEVD_UEVENT: + dbg("udevd message (UEVENT) received"); + envbuf_size = size - offsetof(struct udevd_msg, envbuf); + dbg("envbuf_size=%i", envbuf_size); + msg = get_msg_from_envbuf(usend_msg.envbuf, envbuf_size); + if (msg == NULL) + return NULL; + return msg; + case UDEVD_STOP_EXEC_QUEUE: + dbg("udevd message (STOP_EXEC_QUEUE) received"); + stop_exec_q = 1; + break; + case UDEVD_START_EXEC_QUEUE: + dbg("udevd message (START_EXEC_QUEUE) received"); + stop_exec_q = 0; + exec_queue_manager(); + break; + default: + dbg("unknown message type"); + } + return NULL; +} - /* 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; +/* receive the kernel user event message and do some sanity checks */ +static struct uevent_msg *get_uevent_msg(void) +{ + struct uevent_msg *msg; + int bufpos; + ssize_t size; + static char buffer[UEVENT_BUFFER_SIZE + 512]; + char *pos; - 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); + size = recv(uevent_nl_sock, &buffer, sizeof(buffer), 0); + if (size < 0) { + if (errno != EINTR) + dbg("unable to receive udevd message"); + return NULL; + } - /* remember some keys for further processing */ - if (strncmp(key, "ACTION=", 7) == 0) - msg->action = &key[7]; + if ((size_t)size > sizeof(buffer)-1) + size = sizeof(buffer)-1; + buffer[size] = '\0'; + dbg("uevent_size=%i", size); - if (strncmp(key, "DEVPATH=", 8) == 0) - msg->devpath = &key[8]; + /* start of event payload */ + bufpos = strlen(buffer)+1; + msg = get_msg_from_envbuf(&buffer[bufpos], size-bufpos); + if (msg == NULL) + return NULL; - if (strncmp(key, "SUBSYSTEM=", 10) == 0) - msg->subsystem = &key[10]; + /* validate message */ + pos = strchr(buffer, '@'); + if (pos == NULL) { + dbg("invalid uevent '%s'", buffer); + free(msg); + return NULL; + } + pos[0] = '\0'; - if (strncmp(key, "SEQNUM=", 7) == 0) - msg->seqnum = strtoull(&key[7], NULL, 10); + if (msg->action == NULL) { + dbg("no ACTION in payload found, skip event '%s'", buffer); + free(msg); + return NULL; + } - if (strncmp(key, "PHYSDEVPATH=", 12) == 0) - msg->physdevpath = &key[12]; + if (strcmp(msg->action, buffer) != 0) { + dbg("ACTION in payload does not match uevent, skip event '%s'", buffer); + free(msg); + return NULL; } - msg->envp[i++] = "UDEVD_EVENT=1"; - msg->envp[i] = NULL; return msg; } @@ -532,7 +628,7 @@ do_write: static void udev_done(int pid) { /* find msg associated with pid and delete it */ - struct hotplug_msg *msg; + struct uevent_msg *msg; list_for_each_entry(msg, &running_list, node) { if (msg->pid == pid) { @@ -575,7 +671,7 @@ static void user_sighandler(void) } } -static int init_udevsend_socket(void) +static int init_udevd_socket(void) { struct sockaddr_un saddr; socklen_t addrlen; @@ -588,22 +684,50 @@ static int init_udevsend_socket(void) strcpy(&saddr.sun_path[1], UDEVD_SOCK_PATH); addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path+1) + 1; - udevsendsock = socket(AF_LOCAL, SOCK_DGRAM, 0); - if (udevsendsock == -1) { - dbg("error getting socket, %s", strerror(errno)); + udevd_sock = socket(AF_LOCAL, SOCK_DGRAM, 0); + if (udevd_sock == -1) { + err("error getting socket, %s", strerror(errno)); return -1; } /* the bind takes care of ensuring only one copy running */ - retval = bind(udevsendsock, (struct sockaddr *) &saddr, addrlen); + retval = bind(udevd_sock, (struct sockaddr *) &saddr, addrlen); if (retval < 0) { - dbg("bind failed, %s", strerror(errno)); - close(udevsendsock); + err("bind failed, %s", strerror(errno)); + close(udevd_sock); return -1; } /* enable receiving of the sender credentials */ - setsockopt(udevsendsock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on)); + setsockopt(udevd_sock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on)); + + return 0; +} + +static int init_uevent_nl_sock(void) +{ + struct sockaddr_nl snl; + int retval; + + memset(&snl, 0x00, sizeof(struct sockaddr_nl)); + snl.nl_family = AF_NETLINK; + snl.nl_pid = getpid(); + snl.nl_groups = 0xffffffff; + + uevent_nl_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT); + if (uevent_nl_sock == -1) { + dbg("error getting socket, %s", strerror(errno)); + return -1; + } + + retval = bind(uevent_nl_sock, (struct sockaddr *) &snl, + sizeof(struct sockaddr_nl)); + if (retval < 0) { + dbg("bind failed, %s", strerror(errno)); + close(uevent_nl_sock); + uevent_nl_sock = -1; + return -1; + } return 0; } @@ -617,12 +741,14 @@ int main(int argc, char *argv[], char *envp[]) struct sigaction act; fd_set readfds; const char *udevd_expected_seqnum; + int uevent_nl_active = 0; logging_init("udevd"); + udev_init_config(); dbg("version %s", UDEV_VERSION); if (getuid() != 0) { - dbg("need to be root, exit"); + err("need to be root, exit"); goto exit; } @@ -636,7 +762,7 @@ int main(int argc, char *argv[], char *envp[]) dbg("damonized fork running"); break; case -1: - dbg("fork of daemon failed"); + err("fork of daemon failed"); goto exit; default: logging_close(); @@ -664,36 +790,36 @@ int main(int argc, char *argv[], char *envp[]) if (fd > 2) close(fd); } else - dbg("error opening /dev/null %s", strerror(errno)); + err("error opening /dev/null %s", strerror(errno)); /* setup signal handler pipe */ retval = pipe(pipefds); if (retval < 0) { - dbg("error getting pipes: %s", strerror(errno)); + err("error getting pipes: %s", strerror(errno)); goto exit; } retval = fcntl(pipefds[0], F_SETFL, O_NONBLOCK); if (retval < 0) { - dbg("error fcntl on read pipe: %s", strerror(errno)); + err("error fcntl on read pipe: %s", strerror(errno)); goto exit; } retval = fcntl(pipefds[0], F_SETFD, FD_CLOEXEC); if (retval < 0) - dbg("error fcntl on read pipe: %s", strerror(errno)); + err("error fcntl on read pipe: %s", strerror(errno)); retval = fcntl(pipefds[1], F_SETFL, O_NONBLOCK); if (retval < 0) { - dbg("error fcntl on write pipe: %s", strerror(errno)); + err("error fcntl on write pipe: %s", strerror(errno)); goto exit; } retval = fcntl(pipefds[1], F_SETFD, FD_CLOEXEC); if (retval < 0) - dbg("error fcntl on write pipe: %s", strerror(errno)); + err("error fcntl on write pipe: %s", strerror(errno)); /* set signal handlers */ memset(&act, 0x00, sizeof(struct sigaction)); - act.sa_handler = (void (*) (int))sig_handler; + act.sa_handler = (void (*)(int)) sig_handler; sigemptyset(&act.sa_mask); act.sa_flags = SA_RESTART; sigaction(SIGINT, &act, NULL); @@ -701,11 +827,15 @@ int main(int argc, char *argv[], char *envp[]) sigaction(SIGALRM, &act, NULL); sigaction(SIGCHLD, &act, NULL); - if (init_udevsend_socket() < 0) { + if (init_uevent_nl_sock() < 0) { + dbg("uevent socket not available"); + } + + if (init_udevd_socket() < 0) { if (errno == EADDRINUSE) dbg("another udevd running, exit"); else - dbg("error initialising udevsend socket: %s", strerror(errno)); + dbg("error initialising udevd socket: %s", strerror(errno)); goto exit; } @@ -713,7 +843,7 @@ int main(int argc, char *argv[], char *envp[]) /* possible override of udev binary, used for testing */ udev_bin = getenv("UDEV_BIN"); if (udev_bin != NULL) - dbg("udev binary is set to '%s'", udev_bin); + info("udev binary is set to '%s'", udev_bin); else udev_bin = UDEV_BIN; @@ -721,7 +851,7 @@ int main(int argc, char *argv[], char *envp[]) udevd_expected_seqnum = getenv("UDEVD_EXPECTED_SEQNUM"); if (udevd_expected_seqnum != NULL) { expected_seqnum = strtoull(udevd_expected_seqnum, NULL, 10); - dbg("initialize expected_seqnum to %llu", expected_seqnum); + info("initialize expected_seqnum to %llu", expected_seqnum); } /* get current time to provide shorter timeout on startup */ @@ -729,11 +859,13 @@ int main(int argc, char *argv[], char *envp[]) startup_time = info.uptime; FD_ZERO(&readfds); - FD_SET(udevsendsock, &readfds); + FD_SET(udevd_sock, &readfds); + if (uevent_nl_sock != -1) + FD_SET(uevent_nl_sock, &readfds); FD_SET(pipefds[0], &readfds); - maxsockplus = udevsendsock+1; + maxsockplus = udevd_sock+1; while (1) { - struct hotplug_msg *msg; + struct uevent_msg *msg; fd_set workreadfds = readfds; retval = select(maxsockplus, &workreadfds, NULL, NULL, NULL); @@ -744,10 +876,29 @@ int main(int argc, char *argv[], char *envp[]) continue; } - if (FD_ISSET(udevsendsock, &workreadfds)) { - msg = get_udevsend_msg(); - if (msg) + if (FD_ISSET(udevd_sock, &workreadfds)) { + msg = get_udevd_msg(); + if (msg) { + /* discard kernel messages if netlink is active */ + if (uevent_nl_active && msg->seqnum != 0) { + dbg("skip uevent_helper message, netlink is active"); + free(msg); + continue; + } msg_queue_insert(msg); + } + } + + if (FD_ISSET(uevent_nl_sock, &workreadfds)) { + msg = get_uevent_msg(); + if (msg) { + msg_queue_insert(msg); + /* disable udevsend with first netlink message */ + if (!uevent_nl_active) { + info("uevent_nl message received, disable uevent_helper messages"); + uevent_nl_active = 1; + } + } } if (FD_ISSET(pipefds[0], &workreadfds)) @@ -771,7 +922,8 @@ int main(int argc, char *argv[], char *envp[]) } run_exec_q = 0; - exec_queue_manager(); + if (!stop_exec_q) + exec_queue_manager(); } }