volume_id: old md metadata has only 32 bit for the uuid

[elogind.git] / extras / volume_id / vol_id.c

diff --git a/extras/volume_id/vol_id.c b/extras/volume_id/vol_id.c
index 7bdfda17e7ab5b967ac923935cbee08c7351e140..0427d70da199e312e518c5e48792350de9cc4e26 100644 (file)
--- a/extras/volume_id/vol_id.c
+++ b/extras/volume_id/vol_id.c
@@ -27,6 +27,8 @@
 #include <unistd.h>
 #include <string.h>
 #include <ctype.h>
+#include <errno.h>
+#include <pwd.h>
 #include <grp.h>
 #include <sys/ioctl.h>
 
@@ -114,6 +116,7 @@ int main(int argc, char *argv[])
                            "  -t             filesystem type\n"
                            "  -l             filesystem label\n"
                            "  -u             filesystem uuid\n"
+                           "  -L             raw label\n"
                            " --skip-raid     don't probe for raid\n"
                            " --probe-all     find possibly conflicting signatures\n"
                            " --help\n"
@@ -123,6 +126,7 @@ int main(int argc, char *argv[])
                PRINT_TYPE,
                PRINT_LABEL,
                PRINT_UUID,
+               PRINT_RAW_LABEL,
        } print = PRINT_EXPORT;
        struct volume_id *vid = NULL;
        static char name[VOLUME_ID_LABEL_SIZE];
@@ -131,8 +135,7 @@ int main(int argc, char *argv[])
        int skip_raid = 0;
        int probe_all = 0;
        const char *node = NULL;
-       uid_t nobody_uid;
-       gid_t nobody_gid;
+       struct passwd *pw;
        int retval;
        int rc = 0;
 
@@ -152,6 +155,8 @@ int main(int argc, char *argv[])
                        print = PRINT_LABEL;
                } else if (strcmp(arg, "-u") == 0) {
                        print = PRINT_UUID;
+               } else if (strcmp(arg, "-L") == 0) {
+                       print = PRINT_RAW_LABEL;
                } else if (strcmp(arg, "--skip-raid") == 0) {
                        skip_raid = 1;
                } else if (strcmp(arg, "--probe-all") == 0) {
@@ -178,15 +183,17 @@ int main(int argc, char *argv[])
 
        if (ioctl(vid->fd, BLKGETSIZE64, &size) != 0)
                size = 0;
-       dbg("BLKGETSIZE64=%llu", size);
+       dbg("BLKGETSIZE64=%llu", (unsigned long long)size);
 
-       /* drop all privileges */
-       nobody_uid = lookup_user("nobody");
-       nobody_gid = lookup_group("nogroup");
-       if (nobody_uid > 0 && nobody_gid > 0) {
+       /* try to drop all privileges before reading disk content */
+       pw = getpwnam ("nobody");
+       if (pw != NULL && pw->pw_uid > 0 && pw->pw_gid > 0) {
+               dbg("dropping privileges to %u:%u",
+                   (unsigned int)pw->pw_uid, (unsigned int)pw->pw_gid);
                if (setgroups(0, NULL) != 0 ||
-                   setgid(nobody_gid) != 0 ||
-                   setuid(nobody_uid) != 0) {
+                   setgid(pw->pw_gid) != 0 ||
+                   setuid(pw->pw_uid) != 0) {
+                       fprintf(stderr, "error dropping privileges: %s\n", strerror(errno));
                        rc = 3;
                        goto exit;
                }
@@ -304,6 +311,13 @@ int main(int argc, char *argv[])
                }
                printf("%s\n", vid->uuid);
                break;
+       case PRINT_RAW_LABEL:
+               if (vid->label[0] == '\0' || vid->usage_id == VOLUME_ID_RAID) {
+                       rc = 3;
+                       goto exit;
+               }
+               printf("%s\n", vid->label);
+               break;
        }
 
 exit: