X-Git-Url: https://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=udev%2Fudev-util.c;h=3d5eb7657c40b812e14b6a395e5e8a0629930710;hp=59c4d194dd4d1a447a9f29bd5035eb22205ced70;hb=db71b500b2fe1fc74c4d9b60082cb142283b6eda;hpb=a390e6f764087b74b1567e1daf1f1c41eae42c74

diff --git a/udev/udev-util.c b/udev/udev-util.c
index 59c4d194d..3d5eb7657 100644
--- a/udev/udev-util.c
+++ b/udev/udev-util.c
@@ -25,10 +25,11 @@
 #include <ctype.h>
 #include <pwd.h>
 #include <grp.h>
+#include <sys/wait.h>
 
 #include "udev.h"
 
-int create_path(struct udev *udev, const char *path)
+int util_create_path(struct udev *udev, const char *path)
 {
 	char p[UTIL_PATH_SIZE];
 	char *pos;
@@ -48,7 +49,7 @@ int create_path(struct udev *udev, const char *path)
 	if (stat(p, &stats) == 0 && (stats.st_mode & S_IFMT) == S_IFDIR)
 		return 0;
 
-	if (create_path(udev, p) != 0)
+	if (util_create_path(udev, p) != 0)
 		return -1;
 
 	dbg(udev, "mkdir '%s'\n", p);
@@ -64,7 +65,7 @@ int create_path(struct udev *udev, const char *path)
 	return -1;
 }
 
-int delete_path(struct udev *udev, const char *path)
+int util_delete_path(struct udev *udev, const char *path)
 {
 	char p[UTIL_PATH_SIZE];
 	char *pos;
@@ -101,7 +102,7 @@ int delete_path(struct udev *udev, const char *path)
 /* Reset permissions on the device node, before unlinking it to make sure,
  * that permisions of possible hard links will be removed too.
  */
-int unlink_secure(struct udev *udev, const char *filename)
+int util_unlink_secure(struct udev *udev, const char *filename)
 {
 	int retval;
 
@@ -123,38 +124,329 @@ int unlink_secure(struct udev *udev, const char *filename)
 	return retval;
 }
 
-uid_t lookup_user(struct udev *udev, const char *user)
+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 = 0;
+	uid_t uid;
 
-	errno = 0;
-	pw = getpwnam(user);
-	if (pw == NULL) {
-		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);
-	} else
-		uid = pw->pw_uid;
+	if (strcmp(user, "root") == 0)
+		return 0;
+	uid = strtoul(user, &endptr, 10);
+	if (endptr[0] == '\0')
+		return uid;
 
-	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 lookup_group(struct udev *udev, const char *group)
+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;
-	gr = getgrnam(group);
-	if (gr == NULL) {
-		if (errno == 0 || errno == ENOENT || errno == ESRCH)
-			err(udev, "specified group '%s' unknown\n", group);
+	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
-			err(udev, "error resolving group '%s': %m\n", group);
-	} else
-		gid = gr->gr_gid;
+			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;
+}
 
-	return gid;
+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;
 }