/* * udevmonitor.c * * Copyright (C) 2004-2005 Kay Sievers * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the * Free Software Foundation version 2 of the License. * * This program is distributed in the hope that it will be useful, but * WITHOUT ANY WARRANTY; without even the implied warranty of * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * General Public License for more details. * * You should have received a copy of the GNU General Public License along * with this program; if not, write to the Free Software Foundation, Inc., * 675 Mass Ave, Cambridge, MA 02139, USA. * */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include "udev.h" #include "udevd.h" #include "udev_utils.h" #include "udev_libc_wrapper.h" static int uevent_netlink_sock; static int udev_monitor_sock; static volatile int udev_exit; static int init_udev_monitor_socket(void) { struct sockaddr_un saddr; socklen_t addrlen; const int feature_on = 1; int retval; memset(&saddr, 0x00, sizeof(saddr)); saddr.sun_family = AF_LOCAL; /* use abstract namespace for socket path */ strcpy(&saddr.sun_path[1], "/org/kernel/udev/monitor"); addrlen = offsetof(struct sockaddr_un, sun_path) + strlen(saddr.sun_path+1) + 1; udev_monitor_sock = socket(AF_LOCAL, SOCK_DGRAM, 0); if (udev_monitor_sock == -1) { fprintf(stderr, "error getting socket, %s\n", strerror(errno)); return -1; } /* the bind takes care of ensuring only one copy running */ retval = bind(udev_monitor_sock, (struct sockaddr *) &saddr, addrlen); if (retval < 0) { fprintf(stderr, "bind failed, %s\n", strerror(errno)); close(udev_monitor_sock); udev_monitor_sock = -1; return -1; } /* enable receiving of the sender credentials */ setsockopt(udev_monitor_sock, SOL_SOCKET, SO_PASSCRED, &feature_on, sizeof(feature_on)); return 0; } static int init_uevent_netlink_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_netlink_sock = socket(PF_NETLINK, SOCK_DGRAM, NETLINK_KOBJECT_UEVENT); if (uevent_netlink_sock == -1) { fprintf(stderr, "error getting socket, %s\n", strerror(errno)); return -1; } retval = bind(uevent_netlink_sock, (struct sockaddr *) &snl, sizeof(struct sockaddr_nl)); if (retval < 0) { fprintf(stderr, "bind failed, %s\n", strerror(errno)); close(uevent_netlink_sock); uevent_netlink_sock = -1; return -1; } return 0; } static void asmlinkage sig_handler(int signum) { if (signum == SIGINT || signum == SIGTERM) udev_exit = 1; } int main(int argc, char *argv[]) { struct sigaction act; int env = 0; fd_set readfds; int i; int retval = 0; for (i = 1 ; i < argc; i++) { char *arg = argv[i]; if (strcmp(arg, "--env") == 0 || strcmp(arg, "-e") == 0) { env = 1; } else if (strcmp(arg, "--help") == 0 || strcmp(arg, "-h") == 0){ printf("Usage: udevmonitor [--env]\n" " --env print the whole event environment\n" " --help print this help text\n\n"); exit(0); } else { fprintf(stderr, "unknown option\n\n"); exit(1); } } if (getuid() != 0) { fprintf(stderr, "need to be root, exit\n\n"); exit(2); } /* set signal handlers */ memset(&act, 0x00, sizeof(struct sigaction)); act.sa_handler = (void (*)(int)) sig_handler; sigemptyset(&act.sa_mask); act.sa_flags = SA_RESTART; sigaction(SIGINT, &act, NULL); sigaction(SIGTERM, &act, NULL); retval = init_udev_monitor_socket(); if (retval) goto out; retval = init_uevent_netlink_sock(); if (retval) goto out; printf("udevmonitor prints the received event from the kernel [UEVENT]\n" "and the event which udev sends out after rule processing [UDEV]\n\n"); while (!udev_exit) { static char buf[UEVENT_BUFFER_SIZE*2]; ssize_t buflen; int fdcount; buflen = 0; FD_ZERO(&readfds); if (uevent_netlink_sock > 0) FD_SET(uevent_netlink_sock, &readfds); if (udev_monitor_sock > 0) FD_SET(udev_monitor_sock, &readfds); fdcount = select(UDEV_MAX(uevent_netlink_sock, udev_monitor_sock)+1, &readfds, NULL, NULL, NULL); if (fdcount < 0) { if (errno != EINTR) fprintf(stderr, "error receiving uevent message\n"); continue; } if ((uevent_netlink_sock > 0) && FD_ISSET(uevent_netlink_sock, &readfds)) { buflen = recv(uevent_netlink_sock, &buf, sizeof(buf), 0); if (buflen <= 0) { fprintf(stderr, "error receiving uevent message\n"); continue; } printf("UEVENT[%llu] %s\n", (unsigned long long) time(NULL), buf); } if ((udev_monitor_sock > 0) && FD_ISSET(udev_monitor_sock, &readfds)) { buflen = recv(udev_monitor_sock, &buf, sizeof(buf), 0); if (buflen <= 0) { fprintf(stderr, "error receiving udev message\n"); continue; } printf("UDEV [%llu] %s\n", (unsigned long long) time(NULL), buf); } if (buflen == 0) continue; /* print environment */ if (env) { size_t bufpos; /* start of payload */ bufpos = strlen(buf) + 1; while (bufpos < (size_t)buflen) { int keylen; char *key; key = &buf[bufpos]; keylen = strlen(key); if (keylen == 0) break; printf("%s\n", key); bufpos += keylen + 1; } printf("\n"); } } out: if (uevent_netlink_sock > 0) close(uevent_netlink_sock); if (udev_monitor_sock > 0) close(udev_monitor_sock); if (retval) return 3; return 0; }