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-rw-r--r--util-linux/mkswap.c92
1 files changed, 13 insertions, 79 deletions
diff --git a/util-linux/mkswap.c b/util-linux/mkswap.c
index f718843..226831b 100644
--- a/util-linux/mkswap.c
+++ b/util-linux/mkswap.c
@@ -50,84 +50,6 @@ static void mkswap_selinux_setcontext(int fd, const char *path)
# define mkswap_selinux_setcontext(fd, path) ((void)0)
#endif
-#if ENABLE_FEATURE_MKSWAP_UUID
-static void mkswap_generate_uuid(uint8_t *buf)
-{
- /* http://www.ietf.org/rfc/rfc4122.txt
- * 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1 2 3 4 5 6 7 8 9 0 1
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * | time_low |
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * | time_mid | time_hi_and_version |
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * |clk_seq_and_variant | node (0-1) |
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * | node (2-5) |
- * +-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+-+
- * IOW, uuid has this layout:
- * uint32_t time_low (big endian)
- * uint16_t time_mid (big endian)
- * uint16_t time_hi_and_version (big endian)
- * version is a 4-bit field:
- * 1 Time-based
- * 2 DCE Security, with embedded POSIX UIDs
- * 3 Name-based (MD5)
- * 4 Randomly generated
- * 5 Name-based (SHA-1)
- * uint16_t clk_seq_and_variant (big endian)
- * variant is a 3-bit field:
- * 0xx Reserved, NCS backward compatibility
- * 10x The variant specified in rfc4122
- * 110 Reserved, Microsoft backward compatibility
- * 111 Reserved for future definition
- * uint8_t node[6]
- *
- * For version 4, these bits are set/cleared:
- * time_hi_and_version & 0x0fff | 0x4000
- * clk_seq_and_variant & 0x3fff | 0x8000
- */
- pid_t pid;
- int i;
- char uuid_string[32];
-
- i = open("/dev/urandom", O_RDONLY);
- if (i >= 0) {
- read(i, buf, 16);
- close(i);
- }
- /* Paranoia. /dev/urandom may be missing.
- * rand() is guaranteed to generate at least [0, 2^15) range,
- * but lowest bits in some libc are not so "random". */
- srand(monotonic_us());
- pid = getpid();
- while (1) {
- for (i = 0; i < 16; i++)
- buf[i] ^= rand() >> 5;
- if (pid == 0)
- break;
- srand(pid);
- pid = 0;
- }
-
- /* version = 4 */
- buf[4 + 2 ] = (buf[4 + 2 ] & 0x0f) | 0x40;
- /* variant = 10x */
- buf[4 + 2 + 2] = (buf[4 + 2 + 2] & 0x3f) | 0x80;
-
- bin2hex(uuid_string, (void*) buf, 16);
- /* f.e. UUID=dfd9c173-be52-4d27-99a5-c34c6c2ff55f */
- printf("UUID=%.8s" "-%.4s-%.4s-%.4s-%.12s\n",
- uuid_string,
- uuid_string+8,
- uuid_string+8+4,
- uuid_string+8+4+4,
- uuid_string+8+4+4+4
- );
-}
-#else
-# define mkswap_generate_uuid(buf) ((void)0)
-#endif
-
#if 0 /* from Linux 2.6.23 */
/*
* Magic header for a swap area. The first part of the union is
@@ -190,7 +112,19 @@ int mkswap_main(int argc, char **argv)
// Make a header. hdr is zero-filled so far...
hdr[0] = 1;
hdr[1] = (len / pagesize) - 1;
- mkswap_generate_uuid((void*) &hdr[3]);
+#if ENABLE_FEATURE_MKSWAP_UUID
+ char uuid_string[32];
+ generate_uuid((void*) &hdr[3]);
+ bin2hex(uuid_string, (void*) &hdr[3], 16);
+ /* f.e. UUID=dfd9c173-be52-4d27-99a5-c34c6c2ff55f */
+ printf("UUID=%.8s" "-%.4s-%.4s-%.4s-%.12s\n",
+ uuid_string,
+ uuid_string+8,
+ uuid_string+8+4,
+ uuid_string+8+4+4,
+ uuid_string+8+4+4+4
+ );
+#endif
// Write the header. Sync to disk because some kernel versions check
// signature on disk (not in cache) during swapon.