| /* |
| FUSE: Filesystem in Userspace |
| Copyright (C) 2001-2007 Miklos Szeredi <miklos@szeredi.hu> |
| |
| This program can be distributed under the terms of the GNU LGPL. |
| See the file COPYING.LIB. |
| */ |
| |
| #include "mount_util.h" |
| #include <stdio.h> |
| #include <unistd.h> |
| #include <stdlib.h> |
| #include <string.h> |
| #include <dirent.h> |
| #include <errno.h> |
| #include <limits.h> |
| #include <sys/stat.h> |
| #include <sys/wait.h> |
| |
| int fuse_mnt_add_mount(const char *progname, const char *fsname, |
| const char *mnt, const char *type, const char *opts) |
| { |
| int res; |
| int status; |
| |
| res = fork(); |
| if (res == -1) { |
| fprintf(stderr, "%s: fork: %s\n", progname, strerror(errno)); |
| return -1; |
| } |
| if (res == 0) { |
| char templ[] = "/tmp/fusermountXXXXXX"; |
| char *tmp; |
| |
| setuid(geteuid()); |
| |
| /* |
| * hide in a directory, where mount isn't able to resolve |
| * fsname as a valid path |
| */ |
| tmp = mkdtemp(templ); |
| if (!tmp) { |
| fprintf(stderr, "%s: failed to create temporary directory\n", |
| progname); |
| exit(1); |
| } |
| if (chdir(tmp)) { |
| fprintf(stderr, "%s: failed to chdir to %s: %s\n", |
| progname, tmp, strerror(errno)); |
| exit(1); |
| } |
| rmdir(tmp); |
| execl("/bin/mount", "/bin/mount", "-i", "-f", "-t", type, "-o", opts, |
| fsname, mnt, NULL); |
| fprintf(stderr, "%s: failed to execute /bin/mount: %s\n", progname, |
| strerror(errno)); |
| exit(1); |
| } |
| res = waitpid(res, &status, 0); |
| if (res == -1) { |
| fprintf(stderr, "%s: waitpid: %s\n", progname, strerror(errno)); |
| return -1; |
| } |
| if (status != 0) |
| return -1; |
| |
| return 0; |
| } |
| |
| int fuse_mnt_umount(const char *progname, const char *mnt, int lazy) |
| { |
| int res; |
| int status; |
| |
| res = fork(); |
| if (res == -1) { |
| fprintf(stderr, "%s: fork: %s\n", progname, strerror(errno)); |
| return -1; |
| } |
| if (res == 0) { |
| setuid(geteuid()); |
| execl("/bin/umount", "/bin/umount", "-i", mnt, lazy ? "-l" : NULL, |
| NULL); |
| fprintf(stderr, "%s: failed to execute /bin/umount: %s\n", progname, |
| strerror(errno)); |
| exit(1); |
| } |
| res = waitpid(res, &status, 0); |
| if (res == -1) { |
| fprintf(stderr, "%s: waitpid: %s\n", progname, strerror(errno)); |
| return -1; |
| } |
| if (status != 0) |
| return -1; |
| |
| return 0; |
| } |
| |
| char *fuse_mnt_resolve_path(const char *progname, const char *orig) |
| { |
| char buf[PATH_MAX]; |
| char *copy; |
| char *dst; |
| char *end; |
| char *lastcomp; |
| const char *toresolv; |
| |
| if (!orig[0]) { |
| fprintf(stderr, "%s: invalid mountpoint '%s'\n", progname, orig); |
| return NULL; |
| } |
| |
| copy = strdup(orig); |
| if (copy == NULL) { |
| fprintf(stderr, "%s: failed to allocate memory\n", progname); |
| return NULL; |
| } |
| |
| toresolv = copy; |
| lastcomp = NULL; |
| for (end = copy + strlen(copy) - 1; end > copy && *end == '/'; end --); |
| if (end[0] != '/') { |
| char *tmp; |
| end[1] = '\0'; |
| tmp = strrchr(copy, '/'); |
| if (tmp == NULL) { |
| lastcomp = copy; |
| toresolv = "."; |
| } else { |
| lastcomp = tmp + 1; |
| if (tmp == copy) |
| toresolv = "/"; |
| } |
| if (strcmp(lastcomp, ".") == 0 || strcmp(lastcomp, "..") == 0) { |
| lastcomp = NULL; |
| toresolv = copy; |
| } |
| else if (tmp) |
| tmp[0] = '\0'; |
| } |
| if (realpath(toresolv, buf) == NULL) { |
| fprintf(stderr, "%s: bad mount point %s: %s\n", progname, orig, |
| strerror(errno)); |
| free(copy); |
| return NULL; |
| } |
| if (lastcomp == NULL) |
| dst = strdup(buf); |
| else { |
| dst = (char *) malloc(strlen(buf) + 1 + strlen(lastcomp) + 1); |
| if (dst) { |
| unsigned buflen = strlen(buf); |
| if (buflen && buf[buflen-1] == '/') |
| sprintf(dst, "%s%s", buf, lastcomp); |
| else |
| sprintf(dst, "%s/%s", buf, lastcomp); |
| } |
| } |
| free(copy); |
| if (dst == NULL) |
| fprintf(stderr, "%s: failed to allocate memory\n", progname); |
| return dst; |
| } |
| |
| int fuse_mnt_check_empty(const char *progname, const char *mnt, |
| mode_t rootmode, off_t rootsize) |
| { |
| int isempty = 1; |
| |
| if (S_ISDIR(rootmode)) { |
| struct dirent *ent; |
| DIR *dp = opendir(mnt); |
| if (dp == NULL) { |
| fprintf(stderr, "%s: failed to open mountpoint for reading: %s\n", |
| progname, strerror(errno)); |
| return -1; |
| } |
| while ((ent = readdir(dp)) != NULL) { |
| if (strcmp(ent->d_name, ".") != 0 && |
| strcmp(ent->d_name, "..") != 0) { |
| isempty = 0; |
| break; |
| } |
| } |
| closedir(dp); |
| } else if (rootsize) |
| isempty = 0; |
| |
| if (!isempty) { |
| fprintf(stderr, "%s: mountpoint is not empty\n", progname); |
| fprintf(stderr, "%s: if you are sure this is safe, use the 'nonempty' mount option\n", progname); |
| return -1; |
| } |
| return 0; |
| } |