X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?p=elogind.git;a=blobdiff_plain;f=extras%2Fvolume_id%2Fvol_id.c;h=04e85abb7f8bd02bd69a59ad09a0d112de0bfe5d;hp=53b4cfff0ba9dec02978e710af61ce51343687fd;hb=8b5238670d2e741bc71ae3e79b499682965dc2fd;hpb=2f2c4fa442f33d7eaee02eda016d6149b9aa0be6

diff --git a/extras/volume_id/vol_id.c b/extras/volume_id/vol_id.c
index 53b4cfff0..04e85abb7 100644
--- a/extras/volume_id/vol_id.c
+++ b/extras/volume_id/vol_id.c
@@ -134,6 +134,7 @@ int main(int argc, char *argv[])
 		{ "export", 0, NULL, 'x' },
 		{ "skip-raid", 0, NULL, 's' },
 		{ "probe-all", 0, NULL, 'a' },
+		{ "offset", 1, NULL, 'o' },
 		{ "help", 0, NULL, 'h' },
 		{}
 	};
@@ -147,13 +148,14 @@ int main(int argc, char *argv[])
 	} print = PRINT_EXPORT;
 
 	struct volume_id *vid = NULL;
-	char label_safe[128];
-	char uuid_safe[128];
+	char label_safe[256];
+	char label_enc[256];
+	char uuid_enc[256];
 	uint64_t size;
 	int skip_raid = 0;
 	int probe_all = 0;
+	uint64_t offset = 0;
 	const char *node;
-	struct passwd *pw;
 	int fd;
 	const char *label, *uuid, *type, *type_version, *usage;
 	int retval;
@@ -167,7 +169,7 @@ int main(int argc, char *argv[])
 	while (1) {
 		int option;
 
-		option = getopt_long(argc, argv, "lLutxsah", options, NULL);
+		option = getopt_long(argc, argv, "lLutxsaoh", options, NULL);
 		if (option == -1)
 			break;
 
@@ -193,6 +195,9 @@ int main(int argc, char *argv[])
 		case 'a':
 			probe_all = 1;
 			break;
+		case 'o':
+			offset = strtoull(optarg, NULL, 0);
+			break;
 		case 'h':
 			printf("Usage: vol_id [options] <device>\n"
 			    " --export        export key/value pairs\n"
@@ -202,6 +207,7 @@ int main(int argc, char *argv[])
 			    " --uuid          filesystem uuid\n"
 			    " --skip-raid     don't probe for raid\n"
 			    " --probe-all     find possibly conflicting signatures\n"
+			    " --offset        skip given number of bytes of input\n"
 			    " --help\n\n");
 			goto exit;
 		default:
@@ -236,28 +242,27 @@ int main(int argc, char *argv[])
 	dbg("BLKGETSIZE64=%llu", (unsigned long long)size);
 
 	/* 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(pw->pw_gid) != 0 ||
-		    setuid(pw->pw_uid) != 0) {
-			fprintf(stderr, "error dropping privileges: %s\n", strerror(errno));
-			rc = 3;
-			goto exit;
+	if (getuid() == 0) {
+		struct passwd *pw;
+
+		pw = getpwnam("nobody");
+		if (pw != NULL && pw->pw_uid > 0 && pw->pw_gid > 0) {
+			if (setgroups(0, NULL) != 0 ||
+			    setgid(pw->pw_gid) != 0 ||
+			    setuid(pw->pw_uid) != 0)
+				info("unable to drop privileges: %s\n", strerror(errno));
 		}
 	}
 
 	if (probe_all) {
-		volume_id_all_probers(all_probers, vid, 0, size, NULL);
+		volume_id_all_probers(all_probers, vid, offset, size, NULL);
 		goto exit;
 	}
 
 	if (skip_raid)
-		retval = volume_id_probe_filesystem(vid, 0, size);
+		retval = volume_id_probe_filesystem(vid, offset, size);
 	else
-		retval = volume_id_probe_all(vid, 0, size);
+		retval = volume_id_probe_all(vid, offset, size);
 	if (retval != 0) {
 		fprintf(stderr, "%s: unknown volume type\n", node);
 		rc = 4;
@@ -275,8 +280,9 @@ int main(int argc, char *argv[])
 
 	set_str(label_safe, label, sizeof(label_safe));
 	replace_chars(label_safe, ALLOWED_CHARS_INPUT);
-	set_str(uuid_safe, uuid, sizeof(uuid_safe));
-	replace_chars(uuid_safe, ALLOWED_CHARS_INPUT);
+
+	volume_id_encode_string(label, label_enc, sizeof(label_enc));
+	volume_id_encode_string(uuid, uuid_enc, sizeof(uuid_enc));
 
 	switch (print) {
 	case PRINT_EXPORT:
@@ -284,8 +290,9 @@ int main(int argc, char *argv[])
 		printf("ID_FS_TYPE=%s\n", type);
 		printf("ID_FS_VERSION=%s\n", type_version);
 		printf("ID_FS_UUID=%s\n", uuid);
-		printf("ID_FS_UUID_SAFE=%s\n", uuid_safe);
+		printf("ID_FS_UUID_ENC=%s\n", uuid_enc);
 		printf("ID_FS_LABEL=%s\n", label);
+		printf("ID_FS_LABEL_ENC=%s\n", label_enc);
 		printf("ID_FS_LABEL_SAFE=%s\n", label_safe);
 		break;
 	case PRINT_TYPE:
@@ -299,11 +306,11 @@ int main(int argc, char *argv[])
 		printf("%s\n", label_safe);
 		break;
 	case PRINT_UUID:
-		if (uuid_safe[0] == '\0' || strcmp(usage, "raid") == 0) {
+		if (uuid_enc[0] == '\0' || strcmp(usage, "raid") == 0) {
 			rc = 4;
 			goto exit;
 		}
-		printf("%s\n", uuid_safe);
+		printf("%s\n", uuid_enc);
 		break;
 	case PRINT_LABEL_RAW:
 		if (label[0] == '\0' || strcmp(usage, "raid") == 0) {