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Diffstat (limited to 'sshfs.c')
-rw-r--r--sshfs.c224
1 files changed, 222 insertions, 2 deletions
diff --git a/sshfs.c b/sshfs.c
index d9226d8..0649805 100644
--- a/sshfs.c
+++ b/sshfs.c
@@ -40,6 +40,8 @@
#include <netinet/in.h>
#include <netinet/tcp.h>
#include <glib.h>
+#include <pwd.h>
+#include <grp.h>
#if __APPLE__
# include <strings.h>
# include <libgen.h>
@@ -224,6 +226,13 @@ struct sshfs {
int follow_symlinks;
int no_check_root;
int detect_uid;
+ int idmap;
+ char *uid_file;
+ char *gid_file;
+ GHashTable *uid_map;
+ GHashTable *gid_map;
+ GHashTable *r_uid_map;
+ GHashTable *r_gid_map;
unsigned max_read;
unsigned max_write;
unsigned ssh_ver;
@@ -336,6 +345,12 @@ enum {
KEY_CONFIGFILE,
};
+enum {
+ IDMAP_NONE,
+ IDMAP_USER,
+ IDMAP_FILE,
+};
+
#define SSHFS_OPT(t, p, v) { t, offsetof(struct sshfs, p), v }
static struct fuse_opt sshfs_opts[] = {
@@ -347,8 +362,11 @@ static struct fuse_opt sshfs_opts[] = {
SSHFS_OPT("ssh_protocol=%u", ssh_ver, 0),
SSHFS_OPT("-1", ssh_ver, 1),
SSHFS_OPT("workaround=%s", workarounds, 0),
- SSHFS_OPT("idmap=none", detect_uid, 0),
- SSHFS_OPT("idmap=user", detect_uid, 1),
+ SSHFS_OPT("idmap=none", idmap, IDMAP_NONE),
+ SSHFS_OPT("idmap=user", idmap, IDMAP_USER),
+ SSHFS_OPT("idmap=file", idmap, IDMAP_FILE),
+ SSHFS_OPT("uidfile=%s", uid_file, 0),
+ SSHFS_OPT("gidfile=%s", gid_file, 0),
SSHFS_OPT("sshfs_sync", sync_write, 1),
SSHFS_OPT("no_readahead", sync_read, 1),
SSHFS_OPT("sshfs_debug", debug, 1),
@@ -474,6 +492,15 @@ static int list_empty(const struct list_head *head)
return head->next == head;
}
+/* given a pointer to the uid/gid, and the mapping table, remap the
+ * uid/gid, if necessary */
+static inline void translate_id(uint32_t *id, GHashTable *map)
+{
+ gpointer id_p;
+ if (g_hash_table_lookup_extended(map, GUINT_TO_POINTER(*id), NULL, &id_p))
+ *id = GPOINTER_TO_UINT(id_p);
+}
+
static inline void buf_init(struct buffer *buf, size_t size)
{
if (size) {
@@ -720,6 +747,10 @@ static int buf_get_attrs(struct buffer *buf, struct stat *stbuf, int *flagsp)
if (sshfs.remote_uid_detected && uid == sshfs.remote_uid)
uid = sshfs.local_uid;
#endif /* !__APPLE__ */
+ if (sshfs.idmap == IDMAP_FILE && sshfs.uid_map)
+ translate_id(&uid, sshfs.uid_map);
+ if (sshfs.idmap == IDMAP_FILE && sshfs.gid_map)
+ translate_id(&gid, sshfs.gid_map);
memset(stbuf, 0, sizeof(struct stat));
stbuf->st_mode = mode;
@@ -2243,6 +2274,10 @@ static int sshfs_chown(const char *path, uid_t uid, gid_t gid)
if (sshfs.remote_uid_detected && uid == sshfs.local_uid)
uid = sshfs.remote_uid;
#endif /* !__APPLE__ */
+ if (sshfs.idmap == IDMAP_FILE && sshfs.r_uid_map)
+ translate_id(&uid, sshfs.r_uid_map);
+ if (sshfs.idmap == IDMAP_FILE && sshfs.r_gid_map)
+ translate_id(&gid, sshfs.r_gid_map);
buf_init(&buf, 0);
buf_add_path(&buf, path);
@@ -3221,6 +3256,9 @@ static void usage(const char *progname)
" -o idmap=TYPE user/group ID mapping, possible types are:\n"
" none no translation of the ID space (default)\n"
" user only translate UID of connecting user\n"
+" file translate UIDs/GIDs contained in uidfile/gidfile\n"
+" -o uidfile=FILE file containing username:remote_uid mappings\n"
+" -o gidfile=FILE file containing groupname:remote_gid mappings\n"
" -o ssh_command=CMD execute CMD instead of 'ssh'\n"
" -o ssh_protocol=N ssh protocol to use (default: 2)\n"
" -o sftp_server=SERV path to sftp server or subsystem (default: sftp)\n"
@@ -3551,6 +3589,166 @@ static int ssh_connect(void)
return 0;
}
+/* remove trailing '\n', like the perl func of the same name */
+static inline void chomp(char *line)
+{
+ char *p = line;
+ if ((p = strrchr(line, '\n')))
+ *p = '\0';
+}
+
+/* number of ':' separated fields in a passwd/group file that we care
+ * about */
+#define IDMAP_FIELDS 3
+
+/* given a line from a uidmap or gidmap, parse out the name and id */
+static void parse_idmap_line(char *line, const char* filename,
+ const unsigned int lineno, uint32_t *ret_id, char **ret_name)
+{
+ chomp(line);
+ char *tokens[IDMAP_FIELDS];
+ char *tok;
+ int i;
+ for (i = 0; (tok = strsep(&line, ":")) && (i < IDMAP_FIELDS) ; i++) {
+ tokens[i] = tok;
+ }
+
+ char *name_tok, *id_tok;
+ if (i == 2) {
+ /* assume name:id format */
+ name_tok = tokens[0];
+ id_tok = tokens[1];
+ } else if (i >= IDMAP_FIELDS) {
+ /* assume passwd/group file format */
+ name_tok = tokens[0];
+ id_tok = tokens[2];
+ } else {
+ fprintf(stderr, "Unknown format at line %u of '%s'\n",
+ lineno, filename);
+ exit(1);
+ }
+
+ errno = 0;
+ uint32_t remote_id = strtoul(id_tok, NULL, 10);
+ if (errno) {
+ fprintf(stderr, "Invalid id number on line %u of '%s': %s\n",
+ lineno, filename, strerror(errno));
+ exit(1);
+ }
+
+ *ret_name = strdup(name_tok);
+ *ret_id = remote_id;
+}
+
+/* read a uidmap or gidmap */
+static void read_id_map(char *file, uint32_t *(*map_fn)(char *),
+ const char *name_id, GHashTable **idmap, GHashTable **r_idmap)
+{
+ *idmap = g_hash_table_new(NULL, NULL);
+ *r_idmap = g_hash_table_new(NULL, NULL);
+ FILE *fp;
+ char *line = NULL;
+ size_t len = 0;
+ unsigned int lineno = 0;
+
+ fp = fopen(file, "r");
+ if (fp == NULL) {
+ fprintf(stderr, "failed to open '%s': %s\n",
+ file, strerror(errno));
+ exit(1);
+ }
+
+ while (getline(&line, &len, fp) != EOF) {
+ lineno++;
+ uint32_t remote_id;
+ char *name;
+
+ parse_idmap_line(line, file, lineno, &remote_id, &name);
+
+ uint32_t *local_id = map_fn(name);
+ if (local_id == NULL) {
+ /* not found */
+ DEBUG("%s(%u): no local %s\n", name, remote_id, name_id);
+ free(name);
+ continue;
+ }
+
+ DEBUG("%s: remote %s %u => local %s %u\n",
+ name, name_id, remote_id, name_id, *local_id);
+ g_hash_table_insert(*idmap, GUINT_TO_POINTER(remote_id), GUINT_TO_POINTER(*local_id));
+ g_hash_table_insert(*r_idmap, GUINT_TO_POINTER(*local_id), GUINT_TO_POINTER(remote_id));
+ free(name);
+ free(local_id);
+ }
+
+ if (fclose(fp) == EOF) {
+ fprintf(stderr, "failed to close '%s': %s",
+ file, strerror(errno));
+ exit(1);
+ }
+
+ if (line)
+ free(line);
+}
+
+/* given a username, return a pointer to its uid, or NULL if it doesn't
+ * exist on this system */
+static uint32_t *username_to_uid(char *name)
+{
+ errno = 0;
+ struct passwd *pw = getpwnam(name);
+ if (pw == NULL) {
+ if (errno == 0) {
+ /* "does not exist" */
+ return NULL;
+ }
+ fprintf(stderr, "Failed to look up user '%s': %s\n",
+ name, strerror(errno));
+ exit(1);
+ }
+ uint32_t *r = malloc(sizeof(uint32_t));
+ if (r == NULL) {
+ fprintf(stderr, "sshfs: memory allocation failed\n");
+ abort();
+ }
+ *r = pw->pw_uid;
+ return r;
+}
+
+/* given a groupname, return a pointer to its gid, or NULL if it doesn't
+ * exist on this system */
+static uint32_t *groupname_to_gid(char *name)
+{
+ errno = 0;
+ struct group *gr = getgrnam(name);
+ if (gr == NULL) {
+ if (errno == 0) {
+ /* "does not exist" */
+ return NULL;
+ }
+ fprintf(stderr, "Failed to look up group '%s': %s\n",
+ name, strerror(errno));
+ exit(1);
+ }
+ uint32_t *r = malloc(sizeof(uint32_t));
+ if (r == NULL) {
+ fprintf(stderr, "sshfs: memory allocation failed\n");
+ abort();
+ }
+ *r = gr->gr_gid;
+ return r;
+}
+
+static inline void load_uid_map(void)
+{
+ read_id_map(sshfs.uid_file, &username_to_uid, "uid", &sshfs.uid_map, &sshfs.r_uid_map);
+}
+
+static inline void load_gid_map(void)
+{
+ read_id_map(sshfs.gid_file, &groupname_to_gid, "gid", &sshfs.gid_map, &sshfs.r_gid_map);
+}
+
#if __APPLE__
int main(int argc, char *argv[], __unused char *envp[], char **exec_path)
#else
@@ -3595,7 +3793,10 @@ int main(int argc, char *argv[])
sshfs.delay_connect = 0;
#if __APPLE__
sshfs.detect_uid = 1;
+#else
+ sshfs.detect_uid = 0;
#endif
+ sshfs.idmap = IDMAP_NONE;
ssh_add_arg("ssh");
ssh_add_arg("-x");
ssh_add_arg("-a");
@@ -3605,6 +3806,25 @@ int main(int argc, char *argv[])
parse_workarounds() == -1)
exit(1);
+ if (sshfs.idmap == IDMAP_USER)
+ sshfs.detect_uid = 1;
+ else if (sshfs.idmap == IDMAP_FILE) {
+ sshfs.uid_map = NULL;
+ sshfs.gid_map = NULL;
+ sshfs.r_uid_map = NULL;
+ sshfs.r_gid_map = NULL;
+ if (!sshfs.uid_file && !sshfs.gid_file) {
+ fprintf(stderr, "need a uid_file or gid_file with idmap=file\n");
+ exit(1);
+ }
+ if (sshfs.uid_file)
+ load_uid_map();
+ if (sshfs.gid_file)
+ load_gid_map();
+ }
+ free(sshfs.uid_file);
+ free(sshfs.gid_file);
+
DEBUG("SSHFS version %s\n", PACKAGE_VERSION);
if (sshfs.password_stdin) {
generated by cgit v1.2.3 (git 2.25.1) at 2024-11-19 12:27:41 +0000