diff options
Diffstat (limited to 'fuse/mount_bsd.c')
| -rw-r--r-- | fuse/mount_bsd.c | 388 |
1 files changed, 388 insertions, 0 deletions
diff --git a/fuse/mount_bsd.c b/fuse/mount_bsd.c new file mode 100644 index 000000000..62443ac25 --- /dev/null +++ b/fuse/mount_bsd.c @@ -0,0 +1,388 @@ +/* + FUSE: Filesystem in Userspace + Copyright (C) 2005-2008 Csaba Henk <csaba.henk@creo.hu> + + This program can be distributed under the terms of the GNU LGPLv2. + See the file COPYING.LIB. +*/ + +#include "fuse_i.h" +#include "fuse_misc.h" +#include "fuse_opt.h" + +#include <sys/stat.h> +#include <sys/wait.h> +#include <sys/sysctl.h> +#include <sys/user.h> +#include <stdio.h> +#include <stdlib.h> +#include <unistd.h> +#include <stddef.h> +#include <fcntl.h> +#include <errno.h> +#include <string.h> +#include <paths.h> +#include <limits.h> + +#define FUSERMOUNT_PROG "mount_fusefs" +#define FUSE_DEV_TRUNK "/dev/fuse" + +enum { + KEY_ALLOW_ROOT, + KEY_RO, + KEY_HELP, + KEY_VERSION, + KEY_KERN +}; + +struct mount_opts { + int allow_other; + int allow_root; + int ishelp; + char *kernel_opts; +}; + +#define FUSE_DUAL_OPT_KEY(templ, key) \ + FUSE_OPT_KEY(templ, key), FUSE_OPT_KEY("no" templ, key) + +static const struct fuse_opt fuse_mount_opts[] = { + { "allow_other", offsetof(struct mount_opts, allow_other), 1 }, + { "allow_root", offsetof(struct mount_opts, allow_root), 1 }, + FUSE_OPT_KEY("allow_root", KEY_ALLOW_ROOT), + FUSE_OPT_KEY("-r", KEY_RO), + FUSE_OPT_KEY("-h", KEY_HELP), + FUSE_OPT_KEY("--help", KEY_HELP), + FUSE_OPT_KEY("-V", KEY_VERSION), + FUSE_OPT_KEY("--version", KEY_VERSION), + /* standard FreeBSD mount options */ + FUSE_DUAL_OPT_KEY("dev", KEY_KERN), + FUSE_DUAL_OPT_KEY("async", KEY_KERN), + FUSE_DUAL_OPT_KEY("atime", KEY_KERN), + FUSE_DUAL_OPT_KEY("dev", KEY_KERN), + FUSE_DUAL_OPT_KEY("exec", KEY_KERN), + FUSE_DUAL_OPT_KEY("suid", KEY_KERN), + FUSE_DUAL_OPT_KEY("symfollow", KEY_KERN), + FUSE_DUAL_OPT_KEY("rdonly", KEY_KERN), + FUSE_DUAL_OPT_KEY("sync", KEY_KERN), + FUSE_DUAL_OPT_KEY("union", KEY_KERN), + FUSE_DUAL_OPT_KEY("userquota", KEY_KERN), + FUSE_DUAL_OPT_KEY("groupquota", KEY_KERN), + FUSE_DUAL_OPT_KEY("clusterr", KEY_KERN), + FUSE_DUAL_OPT_KEY("clusterw", KEY_KERN), + FUSE_DUAL_OPT_KEY("suiddir", KEY_KERN), + FUSE_DUAL_OPT_KEY("snapshot", KEY_KERN), + FUSE_DUAL_OPT_KEY("multilabel", KEY_KERN), + FUSE_DUAL_OPT_KEY("acls", KEY_KERN), + FUSE_DUAL_OPT_KEY("force", KEY_KERN), + FUSE_DUAL_OPT_KEY("update", KEY_KERN), + FUSE_DUAL_OPT_KEY("ro", KEY_KERN), + FUSE_DUAL_OPT_KEY("rw", KEY_KERN), + FUSE_DUAL_OPT_KEY("auto", KEY_KERN), + /* options supported under both Linux and FBSD */ + FUSE_DUAL_OPT_KEY("allow_other", KEY_KERN), + FUSE_DUAL_OPT_KEY("default_permissions",KEY_KERN), + FUSE_OPT_KEY("max_read=", KEY_KERN), + FUSE_OPT_KEY("subtype=", KEY_KERN), + /* FBSD FUSE specific mount options */ + FUSE_DUAL_OPT_KEY("private", KEY_KERN), + FUSE_DUAL_OPT_KEY("neglect_shares", KEY_KERN), + FUSE_DUAL_OPT_KEY("push_symlinks_in", KEY_KERN), + FUSE_OPT_KEY("nosync_unmount", KEY_KERN), + /* stock FBSD mountopt parsing routine lets anything be negated... */ + /* + * Linux specific mount options, but let just the mount util + * handle them + */ + FUSE_OPT_KEY("fsname=", KEY_KERN), + FUSE_OPT_KEY("nonempty", KEY_KERN), + FUSE_OPT_KEY("large_read", KEY_KERN), + FUSE_OPT_END +}; + +static void mount_help(void) +{ + fprintf(stderr, + " -o allow_root allow access to root\n" + ); + system(FUSERMOUNT_PROG " --help"); + fputc('\n', stderr); +} + +static void mount_version(void) +{ + system(FUSERMOUNT_PROG " --version"); +} + +static int fuse_mount_opt_proc(void *data, const char *arg, int key, + struct fuse_args *outargs) +{ + struct mount_opts *mo = data; + + switch (key) { + case KEY_ALLOW_ROOT: + if (fuse_opt_add_opt(&mo->kernel_opts, "allow_other") == -1 || + fuse_opt_add_arg(outargs, "-oallow_root") == -1) + return -1; + return 0; + + case KEY_RO: + arg = "ro"; + /* fall through */ + + case KEY_KERN: + return fuse_opt_add_opt(&mo->kernel_opts, arg); + + case KEY_HELP: + mount_help(); + mo->ishelp = 1; + break; + + case KEY_VERSION: + mount_version(); + mo->ishelp = 1; + break; + } + return 1; +} + +void fuse_unmount_compat22(const char *mountpoint) +{ + char dev[128]; + char *ssc, *umount_cmd; + FILE *sf; + int rv; + char seekscript[] = + /* error message is annoying in help output */ + "exec 2>/dev/null; " + "/usr/bin/fstat " FUSE_DEV_TRUNK "* | " + "/usr/bin/awk 'BEGIN{ getline; if (! ($3 == \"PID\" && $10 == \"NAME\")) exit 1; }; " + " { if ($3 == %d) print $10; }' | " + "/usr/bin/sort | " + "/usr/bin/uniq | " + "/usr/bin/awk '{ i += 1; if (i > 1){ exit 1; }; printf; }; END{ if (i == 0) exit 1; }'"; + + (void) mountpoint; + + /* + * If we don't know the fd, we have to resort to the scripted + * solution -- iterating over the fd-s is unpractical, as we + * don't know how many of open files we have. (This could be + * looked up in procfs -- however, that's optional on FBSD; or + * read out from the kmem -- however, that's bound to + * privileges (in fact, that's what happens when we call the + * setgid kmem fstat(1) utility). + */ + if (asprintf(&ssc, seekscript, getpid()) == -1) + return; + + errno = 0; + sf = popen(ssc, "r"); + free(ssc); + if (! sf) + return; + + fgets(dev, sizeof(dev), sf); + rv = pclose(sf); + if (rv) + return; + + if (asprintf(&umount_cmd, "/sbin/umount %s", dev) == -1) + return; + system(umount_cmd); + free(umount_cmd); +} + +static void do_unmount(char *dev, int fd) +{ + char device_path[SPECNAMELEN + 12]; + const char *argv[4]; + const char umount_cmd[] = "/sbin/umount"; + pid_t pid; + + snprintf(device_path, SPECNAMELEN + 12, _PATH_DEV "%s", dev); + + argv[0] = umount_cmd; + argv[1] = "-f"; + argv[2] = device_path; + argv[3] = NULL; + + pid = fork(); + + if (pid == -1) + return; + + if (pid == 0) { + close(fd); + execvp(umount_cmd, (char **)argv); + exit(1); + } + + waitpid(pid, NULL, 0); +} + +void fuse_kern_unmount(const char *mountpoint, int fd) +{ + char *ep, dev[128]; + struct stat sbuf; + + (void)mountpoint; + + if (fstat(fd, &sbuf) == -1) + return; + + devname_r(sbuf.st_rdev, S_IFCHR, dev, 128); + + if (strncmp(dev, "fuse", 4)) + return; + + strtol(dev + 4, &ep, 10); + if (*ep != '\0') + return; + + do_unmount(dev, fd); +} + +/* Check if kernel is doing init in background */ +static int init_backgrounded(void) +{ + unsigned ibg, len; + + len = sizeof(ibg); + + if (sysctlbyname("vfs.fuse.init_backgrounded", &ibg, &len, NULL, 0)) + return 0; + + return ibg; +} + + +static int fuse_mount_core(const char *mountpoint, const char *opts) +{ + const char *mountprog = FUSERMOUNT_PROG; + int fd; + char *fdnam, *dev; + pid_t pid, cpid; + int status; + + fdnam = getenv("FUSE_DEV_FD"); + + if (fdnam) { + char *ep; + + fd = strtol(fdnam, &ep, 10); + + if (*ep != '\0') { + fprintf(stderr, "invalid value given in FUSE_DEV_FD\n"); + return -1; + } + + if (fd < 0) + return -1; + + goto mount; + } + + dev = getenv("FUSE_DEV_NAME"); + + if (! dev) + dev = (char *)FUSE_DEV_TRUNK; + + if ((fd = open(dev, O_RDWR)) < 0) { + perror("fuse: failed to open fuse device"); + return -1; + } + +mount: + if (getenv("FUSE_NO_MOUNT") || ! mountpoint) + goto out; + + pid = fork(); + cpid = pid; + + if (pid == -1) { + perror("fuse: fork() failed"); + close(fd); + return -1; + } + + if (pid == 0) { + if (! init_backgrounded()) { + /* + * If init is not backgrounded, we have to + * call the mount util backgrounded, to avoid + * deadlock. + */ + + pid = fork(); + + if (pid == -1) { + perror("fuse: fork() failed"); + close(fd); + exit(1); + } + } + + if (pid == 0) { + const char *argv[32]; + int a = 0; + + if (! fdnam && asprintf(&fdnam, "%d", fd) == -1) { + perror("fuse: failed to assemble mount arguments"); + exit(1); + } + + argv[a++] = mountprog; + if (opts) { + argv[a++] = "-o"; + argv[a++] = opts; + } + argv[a++] = fdnam; + argv[a++] = mountpoint; + argv[a++] = NULL; + execvp(mountprog, (char **) argv); + perror("fuse: failed to exec mount program"); + exit(1); + } + + exit(0); + } + + if (waitpid(cpid, &status, 0) == -1 || WEXITSTATUS(status) != 0) { + perror("fuse: failed to mount file system"); + close(fd); + return -1; + } + +out: + return fd; +} + +int fuse_kern_mount(const char *mountpoint, struct fuse_args *args) +{ + struct mount_opts mo; + int res = -1; + + memset(&mo, 0, sizeof(mo)); + /* mount util should not try to spawn the daemon */ + setenv("MOUNT_FUSEFS_SAFE", "1", 1); + /* to notify the mount util it's called from lib */ + setenv("MOUNT_FUSEFS_CALL_BY_LIB", "1", 1); + + if (args && + fuse_opt_parse(args, &mo, fuse_mount_opts, fuse_mount_opt_proc) == -1) + return -1; + + if (mo.allow_other && mo.allow_root) { + fprintf(stderr, "fuse: 'allow_other' and 'allow_root' options are mutually exclusive\n"); + goto out; + } + if (mo.ishelp) + return 0; + + res = fuse_mount_core(mountpoint, mo.kernel_opts); +out: + free(mo.kernel_opts); + return res; +} + +FUSE_SYMVER(".symver fuse_unmount_compat22,fuse_unmount@FUSE_2.2"); |