/*
* libudev - interface to udev device information
*
- * Copyright (C) 2004-2009 Kay Sievers <kay.sievers@vrfy.org>
+ * Copyright (C) 2003-2009 Kay Sievers <kay.sievers@vrfy.org>
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Lesser General Public
#include <ctype.h>
#include <pwd.h>
#include <grp.h>
+#include <sys/prctl.h>
+#include <sys/epoll.h>
#include <sys/wait.h>
#include <sys/param.h>
#include "libudev.h"
#include "libudev-private.h"
-int util_create_path(struct udev *udev, const char *path)
+static int create_path(struct udev *udev, const char *path, bool selinux)
{
char p[UTIL_PATH_SIZE];
char *pos;
struct stat stats;
- int ret;
+ int err;
util_strscpy(p, sizeof(p), path);
pos = strrchr(p, '/');
- if (pos == p || pos == NULL)
+ if (pos == NULL)
return 0;
-
- while (pos[-1] == '/')
+ while (pos != p && pos[-1] == '/')
pos--;
+ if (pos == p)
+ return 0;
pos[0] = '\0';
dbg(udev, "stat '%s'\n", p);
- if (stat(p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR)
- return 0;
+ if (stat(p, &stats) == 0) {
+ if ((stats.st_mode & S_IFMT) == S_IFDIR)
+ return 0;
+ else
+ return -ENOTDIR;
+ }
- if (util_create_path(udev, p) != 0)
- return -1;
+ err = util_create_path(udev, p);
+ if (err != 0)
+ return err;
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 (selinux)
+ udev_selinux_setfscreatecon(udev, p, S_IFDIR|0755);
+ err = mkdir(p, 0755);
+ if (err != 0) {
+ err = -errno;
+ if (err == -EEXIST && stat(p, &stats) == 0) {
+ if ((stats.st_mode & S_IFMT) == S_IFDIR)
+ err = 0;
+ else
+ err = -ENOTDIR;
+ }
+ }
+ if (selinux)
+ udev_selinux_resetfscreatecon(udev);
+ return err;
+}
- if (errno == EEXIST)
- if (stat(p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR)
- return 0;
- return -1;
+int util_create_path(struct udev *udev, const char *path)
+{
+ return create_path(udev, path, false);
+}
+
+int util_create_path_selinux(struct udev *udev, const char *path)
+{
+ return create_path(udev, path, true);
}
int util_delete_path(struct udev *udev, const char *path)
{
char p[UTIL_PATH_SIZE];
char *pos;
- int retval;
+ int err = 0;
- strcpy (p, path);
+ if (path[0] == '/')
+ while(path[1] == '/')
+ path++;
+ util_strscpy(p, sizeof(p), path);
pos = strrchr(p, '/');
if (pos == p || pos == NULL)
return 0;
- while (1) {
+ for (;;) {
*pos = '\0';
pos = strrchr(p, '/');
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);
+ err = rmdir(p);
+ if (err < 0) {
+ if (errno == ENOENT)
+ err = 0;
break;
}
- dbg(udev, "removed '%s'\n", p);
}
- return 0;
+ return err;
}
/* Reset permissions on the device node, before unlinking it to make sure,
- * that permisions of possible hard links will be removed too.
+ * that permissions 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);
+ int err;
- retval = unlink(filename);
+ chown(filename, 0, 0);
+ chmod(filename, 0000);
+ err = unlink(filename);
if (errno == ENOENT)
- retval = 0;
-
- if (retval)
+ err = 0;
+ if (err)
err(udev, "unlink(%s) failed: %m\n", filename);
-
- return retval;
+ return err;
}
uid_t util_lookup_user(struct udev *udev, const char *user)
{
char *endptr;
- int buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
+ size_t buflen = sysconf(_SC_GETPW_R_SIZE_MAX);
char buf[buflen];
struct passwd pwbuf;
struct passwd *pw;
if (endptr[0] == '\0')
return uid;
- errno = 0;
- getpwnam_r(user, &pwbuf, buf, buflen, &pw);
+ errno = getpwnam_r(user, &pwbuf, buf, buflen, &pw);
if (pw != NULL)
return pw->pw_uid;
if (errno == 0 || errno == ENOENT || errno == ESRCH)
gid_t util_lookup_group(struct udev *udev, const char *group)
{
char *endptr;
- int buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
- char buf[buflen];
+ size_t buflen = sysconf(_SC_GETGR_R_SIZE_MAX);
+ char *buf;
struct group grbuf;
struct group *gr;
gid_t gid = 0;
gid = strtoul(group, &endptr, 10);
if (endptr[0] == '\0')
return gid;
+ buf = NULL;
+ gid = 0;
+ for (;;) {
+ char *newbuf;
- 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;
+ newbuf = realloc(buf, buflen);
+ if (!newbuf)
+ break;
+ buf = newbuf;
+ errno = getgrnam_r(group, &grbuf, buf, buflen, &gr);
+ if (gr != NULL) {
+ gid = gr->gr_gid;
+ } else if (errno == ERANGE) {
+ buflen *= 2;
+ continue;
+ } else 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);
+ }
+ break;
+ }
+ free(buf);
+ return gid;
}
/* handle "[<SUBSYSTEM>/<KERNEL>]<attribute>" format */
return 0;
}
+static int run_program_exec(struct udev *udev, int fd_stdout, int fd_stderr,
+ char *const argv[], char **envp, const sigset_t *sigmask)
+{
+ int err;
+ int fd;
+
+ /* discard child output or connect to pipe */
+ fd = open("/dev/null", O_RDWR);
+ if (fd >= 0) {
+ dup2(fd, STDIN_FILENO);
+ if (fd_stdout < 0)
+ dup2(fd, STDOUT_FILENO);
+ if (fd_stderr < 0)
+ dup2(fd, STDERR_FILENO);
+ close(fd);
+ } else {
+ err(udev, "open /dev/null failed: %m\n");
+ }
+
+ /* connect pipes to std{out,err} */
+ if (fd_stdout >= 0) {
+ dup2(fd_stdout, STDOUT_FILENO);
+ close(fd_stdout);
+ }
+ if (fd_stderr >= 0) {
+ dup2(fd_stderr, STDERR_FILENO);
+ close(fd_stderr);
+ }
+
+ /* terminate child in case parent goes away */
+ prctl(PR_SET_PDEATHSIG, SIGTERM);
+
+ /* restore original udev sigmask before exec */
+ if (sigmask)
+ sigprocmask(SIG_SETMASK, sigmask, NULL);
+
+ execve(argv[0], argv, envp);
+
+ /* exec failed */
+ err = -errno;
+ if (err == -ENOENT || err == -ENOTDIR) {
+ /* may be on a filesystem 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]);
+ }
+ return err;
+}
+
+static int run_program_read(struct udev *udev, int fd_stdout, int fd_stderr,
+ char *const argv[], char *result, size_t ressize, size_t *reslen)
+{
+ size_t respos = 0;
+ int fd_ep = -1;
+ struct epoll_event ep_outpipe;
+ struct epoll_event ep_errpipe;
+ int err = 0;
+
+ /* read from child if requested */
+ if (fd_stdout < 0 && fd_stderr < 0)
+ return 0;
+
+ fd_ep = epoll_create1(EPOLL_CLOEXEC);
+ if (fd_ep < 0) {
+ err = -errno;
+ err(udev, "error creating epoll fd: %m\n");
+ goto out;
+ }
+
+ if (fd_stdout >= 0) {
+ memset(&ep_outpipe, 0, sizeof(struct epoll_event));
+ ep_outpipe.events = EPOLLIN;
+ ep_outpipe.data.ptr = &fd_stdout;
+ if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stdout, &ep_outpipe) < 0) {
+ err(udev, "fail to add fd to epoll: %m\n");
+ goto out;
+ }
+ }
+
+ if (fd_stderr >= 0) {
+ memset(&ep_errpipe, 0, sizeof(struct epoll_event));
+ ep_errpipe.events = EPOLLIN;
+ ep_errpipe.data.ptr = &fd_stderr;
+ if (epoll_ctl(fd_ep, EPOLL_CTL_ADD, fd_stderr, &ep_errpipe) < 0) {
+ err(udev, "fail to add fd to epoll: %m\n");
+ goto out;
+ }
+ }
+
+ /* read child output */
+ while (fd_stdout >= 0 || fd_stderr >= 0) {
+ int fdcount;
+ struct epoll_event ev[4];
+ int i;
+
+ fdcount = epoll_wait(fd_ep, ev, ARRAY_SIZE(ev), -1);
+ if (fdcount < 0) {
+ if (errno == EINTR)
+ continue;
+ err(udev, "failed to poll: %m\n");
+ err = -errno;
+ goto out;
+ }
+
+ for (i = 0; i < fdcount; i++) {
+ int *fd = (int *)ev[i].data.ptr;
+
+ if (ev[i].events & EPOLLIN) {
+ ssize_t count;
+ char buf[4096];
+
+ count = read(*fd, buf, sizeof(buf)-1);
+ if (count <= 0)
+ continue;
+ buf[count] = '\0';
+
+ /* store stdout result */
+ if (result != NULL && *fd == fd_stdout) {
+ if (respos + count < ressize) {
+ memcpy(&result[respos], buf, count);
+ respos += count;
+ } else {
+ err(udev, "ressize %zd too short\n", ressize);
+ err = -ENOBUFS;
+ }
+ }
+
+ /* log debug output only if we watch stderr */
+ if (fd_stderr >= 0) {
+ char *pos;
+ char *line;
+
+ pos = buf;
+ while ((line = strsep(&pos, "\n"))) {
+ if (pos != NULL || line[0] != '\0')
+ info(udev, "'%s'(%s) '%s'\n", argv[0], *fd == fd_stdout ? "out" : "err" , line);
+ }
+ }
+ } else if (ev[i].events & EPOLLHUP) {
+ if (epoll_ctl(fd_ep, EPOLL_CTL_DEL, *fd, NULL) < 0) {
+ err = -errno;
+ err(udev, "failed to remove fd from epoll: %m\n");
+ goto out;
+ }
+ *fd = -1;
+ }
+ }
+ }
+
+ /* return the child's stdout string */
+ if (result != NULL) {
+ result[respos] = '\0';
+ dbg(udev, "result='%s'\n", result);
+ if (reslen != NULL)
+ *reslen = respos;
+ }
+out:
+ if (fd_ep >= 0)
+ close(fd_ep);
+ return err;
+}
+
int util_run_program(struct udev *udev, const char *command, char **envp,
- char *result, size_t ressize, size_t *reslen)
+ char *result, size_t ressize, size_t *reslen,
+ const sigset_t *sigmask)
{
int status;
int outpipe[2] = {-1, -1};
pid_t pid;
char arg[UTIL_PATH_SIZE];
char program[UTIL_PATH_SIZE];
- char *argv[(sizeof(arg) / 2) + 1];
- int devnull;
+ char *argv[((sizeof(arg) + 1) / 2) + 1];
int i;
int err = 0;
/* do not separate quotes */
pos++;
argv[i] = strsep(&pos, "\'");
- while (pos != NULL && pos[0] == ' ')
- pos++;
+ if (pos != NULL)
+ while (pos[0] == ' ')
+ pos++;
} else {
argv[i] = strsep(&pos, " ");
+ if (pos != NULL)
+ while (pos[0] == ' ')
+ pos++;
}
dbg(udev, "arg[%i] '%s'\n", i, argv[i]);
i++;
argv[1] = NULL;
}
- /* prepare pipes from child to parent */
+ /* pipes from child to parent */
if (result != NULL || udev_get_log_priority(udev) >= LOG_INFO) {
- if (pipe(outpipe) != 0) {
+ if (pipe2(outpipe, O_NONBLOCK) != 0) {
+ err = -errno;
err(udev, "pipe failed: %m\n");
- return -1;
+ goto out;
}
}
if (udev_get_log_priority(udev) >= LOG_INFO) {
- if (pipe(errpipe) != 0) {
+ if (pipe2(errpipe, O_NONBLOCK) != 0) {
+ err = -errno;
err(udev, "pipe failed: %m\n");
- return -1;
+ goto out;
}
}
pid = fork();
switch(pid) {
case 0:
- /* child closes parent ends of pipes */
- if (outpipe[READ_END] > 0)
+ /* child closes parent's 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]);
+ outpipe[READ_END] = -1;
}
- 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]);
+ if (errpipe[READ_END] >= 0) {
+ close(errpipe[READ_END]);
+ errpipe[READ_END] = -1;
}
+
+ err = run_program_exec(udev, outpipe[WRITE_END], errpipe[WRITE_END], argv, envp, sigmask);
+
_exit(1);
case -1:
err(udev, "fork of '%s' failed: %m\n", argv[0]);
- return -1;
+ err = -1;
+ goto out;
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(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);
- }
+ /* parent closed child's ends of pipes */
+ if (outpipe[WRITE_END] >= 0) {
+ close(outpipe[WRITE_END]);
+ outpipe[WRITE_END] = -1;
+ }
+ if (errpipe[WRITE_END] >= 0) {
+ close(errpipe[WRITE_END]);
+ errpipe[WRITE_END] = -1;
+ }
- /* get stderr */
- if (errpipe[READ_END] > 0 && FD_ISSET(errpipe[READ_END], &readfds)) {
- char errbuf[1024];
- char *pos;
- char *line;
+ err = run_program_read(udev, outpipe[READ_END], errpipe[READ_END], argv, result, ressize, reslen);
- 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 exitcode %i\n", command, WEXITSTATUS(status));
err = -1;
}
}
+
+out:
+ if (outpipe[READ_END] >= 0)
+ close(outpipe[READ_END]);
+ if (outpipe[WRITE_END] >= 0)
+ close(outpipe[WRITE_END]);
+ if (errpipe[READ_END] >= 0)
+ close(errpipe[READ_END]);
+ if (errpipe[WRITE_END] >= 0)
+ close(errpipe[WRITE_END]);
return err;
}