move generate_uuid from mkswap to libbb

Signed-off-by: Vladimir Dronnikov <dronnikov@gmail.com>
Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Vladimir Dronnikov 2009-10-15 09:24:25 +02:00 committed by Denys Vlasenko
parent 7eabffafa5
commit db67a20595
3 changed files with 79 additions and 79 deletions

View File

@ -701,6 +701,9 @@ const char *make_human_readable_str(unsigned long long size,
/* Put a string of hex bytes ("1b2e66fe"...), return advanced pointer */
char *bin2hex(char *buf, const char *cp, int count) FAST_FUNC;
/* Generate a UUID */
void generate_uuid(uint8_t *buf) FAST_FUNC;
/* Last element is marked by mult == 0 */
struct suffix_mult {
char suffix[4];

View File

@ -209,3 +209,66 @@ int FAST_FUNC tcsetattr_stdin_TCSANOW(const struct termios *tp)
{
return tcsetattr(STDIN_FILENO, TCSANOW, tp);
}
void FAST_FUNC 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;
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;
}

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@ -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.