From: kay.sievers@vrfy.org Date: Sat, 6 Nov 2004 13:30:15 +0000 (+0100) Subject: [PATCH] pass the whole event environment to udevd X-Git-Tag: 046~22 X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=commitdiff_plain;h=4a231017ff6e9f66a685b0d1e4e49dc46645bb40 [PATCH] pass the whole event environment to udevd Make _all_ hotplug variables available to the forked udev, the udev callouts and the udev dev.d/ scripts. We put the whole environment into a buffer and send it over the udevd socket. udevd recreates *envp[] and passes it to the exec(). --- diff --git a/udevd.c b/udevd.c index 395cdca88..12fbe1725 100644 --- a/udevd.c +++ b/udevd.c @@ -86,16 +86,6 @@ 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); @@ -132,22 +122,12 @@ static void msg_queue_insert(struct hotplug_msg *msg) static void udev_run(struct hotplug_msg *msg) { 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); + execle(udev_bin, "udev", msg->subsystem, NULL, msg->envp); dbg("exec of child failed"); _exit(1); break; @@ -245,24 +225,23 @@ recheck: } /* 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 +249,8 @@ 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; @@ -281,18 +260,51 @@ 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-1); 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] = NULL; /* if no seqnum is given, we move straight to exec queue */ if (msg->seqnum == 0) { @@ -301,10 +313,8 @@ static void handle_msg(int sock) } else { msg_queue_insert(msg); } - return; -skip: - free(msg); +exit: return; } @@ -511,7 +521,7 @@ int main(int argc, char *argv[], char *envp[]) } if (FD_ISSET(ssock, &workreadfds)) - handle_msg(ssock); + handle_udevsend_msg(ssock); if (FD_ISSET(pipefds[0], &workreadfds)) user_sighandler(); diff --git a/udevd.h b/udevd.h index 657f684e3..b393a28bf 100644 --- a/udevd.h +++ b/udevd.h @@ -30,14 +30,23 @@ #define SEND_WAIT_MAX_SECONDS 3 #define SEND_WAIT_LOOP_PER_SECOND 10 +/* environment buffer, should match the kernel's size in lib/kobject_uevent.h */ +#define HOTPLUG_BUFFER_SIZE 1024 +#define HOTPLUG_NUM_ENVP 32 -struct hotplug_msg { +struct udevsend_msg { char magic[20]; + char envbuf[HOTPLUG_BUFFER_SIZE]; +}; + +struct hotplug_msg { struct list_head list; pid_t pid; - unsigned long long seqnum; long queue_time; - char action[ACTION_SIZE]; - char devpath[DEVPATH_SIZE]; - char subsystem[SUBSYSTEM_SIZE]; + char *action; + char *devpath; + char *subsystem; + unsigned long long seqnum; + char *envp[HOTPLUG_NUM_ENVP]; + char envbuf[]; }; diff --git a/udevsend.c b/udevsend.c index 19922f387..7db2378b8 100644 --- a/udevsend.c +++ b/udevsend.c @@ -70,7 +70,7 @@ static int start_daemon(void) chdir("/"); execl(UDEVD_BIN, "udevd", NULL); dbg("exec of daemon failed"); - exit(1); + _exit(1); case -1: dbg("fork of daemon failed"); return -1; @@ -107,51 +107,29 @@ static void run_udev(const char *subsystem) } } -int main(int argc, char* argv[]) +int main(int argc, char *argv[], char *envp[]) { - struct hotplug_msg msg; - char *action; - char *devpath; - char *subsystem; - char *seqnum; - unsigned long long seq; - int retval = 1; + static struct udevsend_msg usend_msg; + int usend_msg_len; + int i; int loop; - int sock = -1; struct sockaddr_un saddr; socklen_t addrlen; + const char *subsystem_argv; + int subsystem_env = 0; + int bufpos = 0; + int retval = 1; + int sock = -1; int started_daemon = 0; logging_init("udevsend"); dbg("version %s", UDEV_VERSION); - subsystem = get_subsystem(argv[1]); - if (subsystem == NULL) { + subsystem_argv = argv[1]; + if (subsystem_argv == NULL) { dbg("no subsystem"); goto exit; } - dbg("subsystem = '%s'", subsystem); - - devpath = get_devpath(); - if (devpath == NULL) { - dbg("no devpath"); - goto exit; - } - dbg("DEVPATH = '%s'", devpath); - - action = get_action(); - if (action == NULL) { - dbg("no action"); - goto exit; - } - dbg("ACTION = '%s'", action); - - seqnum = get_seqnum(); - if (seqnum == NULL) - seq = 0; - else - seq = strtoull(seqnum, NULL, 10); - dbg("SEQNUM = '%llu'", seq); sock = socket(AF_LOCAL, SOCK_DGRAM, 0); if (sock == -1) { @@ -167,25 +145,49 @@ 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; - memset(&msg, 0x00, sizeof(struct hotplug_msg)); - strcpy(msg.magic, UDEV_MAGIC); - msg.seqnum = seq; - strfieldcpy(msg.action, action); - strfieldcpy(msg.devpath, devpath); - strfieldcpy(msg.subsystem, subsystem); + memset(&usend_msg, 0x00, sizeof(struct udevsend_msg)); + + strcpy(usend_msg.magic, UDEV_MAGIC); + + /* copy all keys to send buffer */ + for (i = 0; envp[i]; i++) { + const char *key; + int keylen; + + key = envp[i]; + keylen = strlen(key); + if (bufpos + keylen >= HOTPLUG_BUFFER_SIZE-1) { + dbg("environment buffer too small, probably not called by the kernel"); + continue; + } + + /* older kernels do not have the SUBSYSTEM in the environment */ + if (strncmp(key, "SUBSYSTEM=", 10) == 0) + subsystem_env = 1; + + dbg("add '%s' to env[%i] buffer", key, i); + strcpy(&usend_msg.envbuf[bufpos], key); + bufpos += keylen + 1; + } + if (!subsystem_env) { + bufpos += sprintf(&usend_msg.envbuf[bufpos], "SUBSYSTEM=%s", subsystem_argv) + 1; + dbg("add 'SUBSYSTEM=%s' to env[%i] buffer from argv", subsystem_argv, i); + } + + usend_msg_len = offsetof(struct udevsend_msg, envbuf) + bufpos; + dbg("usend_msg_len=%i", usend_msg_len); /* If we can't send, try to start daemon and resend message */ loop = SEND_WAIT_MAX_SECONDS * SEND_WAIT_LOOP_PER_SECOND; while (--loop) { - retval = sendto(sock, &msg, sizeof(struct hotplug_msg), 0, - (struct sockaddr *)&saddr, addrlen); + retval = sendto(sock, &usend_msg, usend_msg_len, 0, (struct sockaddr *)&saddr, addrlen); if (retval != -1) { retval = 0; goto exit; } if (errno != ECONNREFUSED) { - dbg("error sending message"); + dbg("error sending message (%s)", strerror(errno)); goto fallback; } @@ -206,7 +208,7 @@ int main(int argc, char* argv[]) fallback: info("unable to connect to event daemon, try to call udev directly"); - run_udev(subsystem); + run_udev(subsystem_argv); exit: if (sock != -1)