/* * Copyright (C) 2004-2008 Kay Sievers <kay.sievers@vrfy.org> * * 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, either version 2 of the License, or * (at your option) any later version. * * 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, see <http://www.gnu.org/licenses/>. */ #include <stdlib.h> #include <stdio.h> #include <stddef.h> #include <unistd.h> #include <string.h> #include <fcntl.h> #include <errno.h> #include <ctype.h> #include <pwd.h> #include <grp.h> #include <sys/wait.h> #include "udev.h" int util_create_path(struct udev *udev, const char *path) { char p[UTIL_PATH_SIZE]; char *pos; struct stat stats; int ret; util_strlcpy(p, path, sizeof(p)); pos = strrchr(p, '/'); if (pos == p || pos == NULL) return 0; while (pos[-1] == '/') pos--; pos[0] = '\0'; dbg(udev, "stat '%s'\n", p); if (stat(p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR) return 0; if (util_create_path(udev, p) != 0) return -1; dbg(udev, "mkdir '%s'\n", p); udev_selinux_setfscreatecon(udev, p, S_IFDIR|0755); ret = mkdir(p, 0755); udev_selinux_resetfscreatecon(udev); if (ret == 0) return 0; if (errno == EEXIST) if (stat(p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR) return 0; return -1; } int util_delete_path(struct udev *udev, const char *path) { char p[UTIL_PATH_SIZE]; char *pos; int retval; strcpy (p, path); pos = strrchr(p, '/'); if (pos == p || pos == NULL) return 0; while (1) { *pos = '\0'; pos = strrchr(p, '/'); /* don't remove the last one */ if ((pos == p) || (pos == NULL)) break; /* remove if empty */ retval = rmdir(p); if (errno == ENOENT) retval = 0; if (retval) { if (errno == ENOTEMPTY) return 0; err(udev, "rmdir(%s) failed: %m\n", p); break; } dbg(udev, "removed '%s'\n", p); } return 0; } /* Reset permissions on the device node, before unlinking it to make sure, * that permisions of possible hard links will be removed too. */ int util_unlink_secure(struct udev *udev, const char *filename) { int retval; retval = chown(filename, 0, 0); if (retval) err(udev, "chown(%s, 0, 0) failed: %m\n", filename); retval = chmod(filename, 0000); if (retval) err(udev, "chmod(%s, 0000) failed: %m\n", filename); retval = unlink(filename); if (errno == ENOENT) retval = 0; if (retval) err(udev, "unlink(%s) failed: %m\n", filename); return retval; } uid_t util_lookup_user(struct udev *udev, const char *user) { char *endptr; int buflen = sysconf(_SC_GETPW_R_SIZE_MAX); char buf[buflen]; struct passwd pwbuf; struct passwd *pw; uid_t uid; if (strcmp(user, "root") == 0) return 0; uid = strtoul(user, &endptr, 10); if (endptr[0] == '\0') return uid; errno = 0; getpwnam_r(user, &pwbuf, buf, buflen, &pw); if (pw != NULL) return pw->pw_uid; if (errno == 0 || errno == ENOENT || errno == ESRCH) err(udev, "specified user '%s' unknown\n", user); else err(udev, "error resolving user '%s': %m\n", user); return 0; } extern gid_t util_lookup_group(struct udev *udev, const char *group) { char *endptr; int buflen = sysconf(_SC_GETGR_R_SIZE_MAX); char buf[buflen]; struct group grbuf; struct group *gr; gid_t gid = 0; if (strcmp(group, "root") == 0) return 0; gid = strtoul(group, &endptr, 10); if (endptr[0] == '\0') return gid; errno = 0; getgrnam_r(group, &grbuf, buf, buflen, &gr); if (gr != NULL) return gr->gr_gid; if (errno == 0 || errno == ENOENT || errno == ESRCH) err(udev, "specified group '%s' unknown\n", group); else err(udev, "error resolving group '%s': %m\n", group); return 0; } /* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */ int util_resolve_subsys_kernel(struct udev *udev, const char *string, char *result, size_t maxsize, int read_value) { char temp[UTIL_PATH_SIZE]; char *subsys; char *sysname; struct udev_device *dev; char *attr; if (string == NULL) string = result; if (string[0] != '[') return -1; util_strlcpy(temp, string, sizeof(temp)); subsys = &temp[1]; sysname = strchr(subsys, '/'); if (sysname == NULL) return -1; sysname[0] = '\0'; sysname = &sysname[1]; attr = strchr(sysname, ']'); if (attr == NULL) return -1; attr[0] = '\0'; attr = &attr[1]; if (attr[0] == '/') attr = &attr[1]; if (attr[0] == '\0') attr = NULL; if (read_value && attr == NULL) return -1; dev = udev_device_new_from_subsystem_sysname(udev, subsys, sysname); if (dev == NULL) return -1; if (read_value) { const char *val; val = udev_device_get_sysattr_value(dev, attr); if (val != NULL) util_strlcpy(result, val, maxsize); else result[0] = '\0'; info(udev, "value '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result); } else { util_strlcpy(result, udev_device_get_syspath(dev), maxsize); if (attr != NULL) { util_strlcat(result, "/", maxsize); util_strlcat(result, attr, maxsize); } info(udev, "path '[%s/%s]%s' is '%s'\n", subsys, sysname, attr, result); } udev_device_unref(dev); return 0; } int util_run_program(struct udev *udev, const char *command, char **envp, char *result, size_t ressize, size_t *reslen) { int status; int outpipe[2] = {-1, -1}; int errpipe[2] = {-1, -1}; pid_t pid; char arg[UTIL_PATH_SIZE]; char program[UTIL_PATH_SIZE]; char *argv[(sizeof(arg) / 2) + 1]; int devnull; int i; int err = 0; /* build argv from command */ util_strlcpy(arg, command, sizeof(arg)); i = 0; if (strchr(arg, ' ') != NULL) { char *pos = arg; while (pos != NULL && pos[0] != '\0') { if (pos[0] == '\'') { /* do not separate quotes */ pos++; argv[i] = strsep(&pos, "\'"); while (pos != NULL && pos[0] == ' ') pos++; } else { argv[i] = strsep(&pos, " "); } dbg(udev, "arg[%i] '%s'\n", i, argv[i]); i++; } argv[i] = NULL; } else { argv[0] = arg; argv[1] = NULL; } info(udev, "'%s'\n", command); /* prepare pipes from child to parent */ if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) { if (pipe(outpipe) != 0) { err(udev, "pipe failed: %m\n"); return -1; } } if (udev_get_log_priority(udev) >= LOG_INFO) { if (pipe(errpipe) != 0) { err(udev, "pipe failed: %m\n"); return -1; } } /* allow programs in /lib/udev/ to be called without the path */ if (strchr(argv[0], '/') == NULL) { util_strlcpy(program, UDEV_PREFIX "/lib/udev/", sizeof(program)); util_strlcat(program, argv[0], sizeof(program)); argv[0] = program; } pid = fork(); switch(pid) { case 0: /* child closes parent ends of pipes */ if (outpipe[READ_END] > 0) close(outpipe[READ_END]); if (errpipe[READ_END] > 0) close(errpipe[READ_END]); /* discard child output or connect to pipe */ devnull = open("/dev/null", O_RDWR); if (devnull > 0) { dup2(devnull, STDIN_FILENO); if (outpipe[WRITE_END] < 0) dup2(devnull, STDOUT_FILENO); if (errpipe[WRITE_END] < 0) dup2(devnull, STDERR_FILENO); close(devnull); } else err(udev, "open /dev/null failed: %m\n"); if (outpipe[WRITE_END] > 0) { dup2(outpipe[WRITE_END], STDOUT_FILENO); close(outpipe[WRITE_END]); } if (errpipe[WRITE_END] > 0) { dup2(errpipe[WRITE_END], STDERR_FILENO); close(errpipe[WRITE_END]); } execve(argv[0], argv, envp); if (errno == ENOENT || errno == ENOTDIR) { /* may be on a filesytem which is not mounted right now */ info(udev, "program '%s' not found\n", argv[0]); } else { /* other problems */ err(udev, "exec of program '%s' failed\n", argv[0]); } _exit(1); case -1: err(udev, "fork of '%s' failed: %m\n", argv[0]); return -1; default: /* read from child if requested */ if (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) { ssize_t count; size_t respos = 0; /* parent closes child ends of pipes */ if (outpipe[WRITE_END] > 0) close(outpipe[WRITE_END]); if (errpipe[WRITE_END] > 0) close(errpipe[WRITE_END]); /* read child output */ while (outpipe[READ_END] > 0 || errpipe[READ_END] > 0) { int fdcount; fd_set readfds; FD_ZERO(&readfds); if (outpipe[READ_END] > 0) FD_SET(outpipe[READ_END], &readfds); if (errpipe[READ_END] > 0) FD_SET(errpipe[READ_END], &readfds); fdcount = select(UDEV_MAX(outpipe[READ_END], errpipe[READ_END])+1, &readfds, NULL, NULL, NULL); if (fdcount < 0) { if (errno == EINTR) continue; err = -1; break; } /* get stdout */ if (outpipe[READ_END] > 0 && FD_ISSET(outpipe[READ_END], &readfds)) { char inbuf[1024]; char *pos; char *line; count = read(outpipe[READ_END], inbuf, sizeof(inbuf)-1); if (count <= 0) { close(outpipe[READ_END]); outpipe[READ_END] = -1; if (count < 0) { err(udev, "stdin read failed: %m\n"); err = -1; } continue; } inbuf[count] = '\0'; /* store result for rule processing */ if (result) { if (respos + count < ressize) { memcpy(&result[respos], inbuf, count); respos += count; } else { err(udev, "ressize %ld too short\n", (long)ressize); err = -1; } } pos = inbuf; while ((line = strsep(&pos, "\n"))) if (pos || line[0] != '\0') info(udev, "'%s' (stdout) '%s'\n", argv[0], line); } /* get stderr */ if (errpipe[READ_END] > 0 && FD_ISSET(errpipe[READ_END], &readfds)) { char errbuf[1024]; char *pos; char *line; count = read(errpipe[READ_END], errbuf, sizeof(errbuf)-1); if (count <= 0) { close(errpipe[READ_END]); errpipe[READ_END] = -1; if (count < 0) err(udev, "stderr read failed: %m\n"); continue; } errbuf[count] = '\0'; pos = errbuf; while ((line = strsep(&pos, "\n"))) if (pos || line[0] != '\0') info(udev, "'%s' (stderr) '%s'\n", argv[0], line); } } if (outpipe[READ_END] > 0) close(outpipe[READ_END]); if (errpipe[READ_END] > 0) close(errpipe[READ_END]); /* return the childs stdout string */ if (result) { result[respos] = '\0'; dbg(udev, "result='%s'\n", result); if (reslen) *reslen = respos; } } waitpid(pid, &status, 0); if (WIFEXITED(status)) { info(udev, "'%s' returned with status %i\n", argv[0], WEXITSTATUS(status)); if (WEXITSTATUS(status) != 0) err = -1; } else { err(udev, "'%s' abnormal exit\n", command); err = -1; } } return err; }