From ee3bcddef71a8ea35db5bc3d26f124ec6530c431 Mon Sep 17 00:00:00 2001 From: Willy Tarreau Date: Sun, 8 Mar 2020 17:48:17 +0100 Subject: [PATCH] MINOR: tools: add a generic function to generate UUIDs We currently have two UUID generation functions, one for the sample fetch and the other one in the SPOE filter. Both were a bit complicated since they were made to support random() implementations returning an arbitrary number of bits, and were throwing away 33 bits every 64. Now we don't need this anymore, so let's have a generic function consuming 64 bits at once and use it as appropriate. --- include/common/standard.h | 1 + src/flt_spoe.c | 29 ++--------------------------- src/sample.c | 25 +------------------------ src/standard.c | 25 +++++++++++++++++++++++++ 4 files changed, 29 insertions(+), 51 deletions(-) diff --git a/include/common/standard.h b/include/common/standard.h index d8bccbafb6..6e1e840b79 100644 --- a/include/common/standard.h +++ b/include/common/standard.h @@ -1551,6 +1551,7 @@ static inline void *my_realloc2(void *ptr, size_t size) int parse_dotted_uints(const char *s, unsigned int **nums, size_t *sz); /* PRNG */ +void ha_generate_uuid(struct buffer *output); void ha_random_seed(const unsigned char *seed, size_t len); void ha_random_jump96(uint32_t dist); uint64_t ha_random64(); diff --git a/src/flt_spoe.c b/src/flt_spoe.c index bcdec08e78..df080d8166 100644 --- a/src/flt_spoe.c +++ b/src/flt_spoe.c @@ -257,33 +257,8 @@ static const char *spoe_appctx_state_str[SPOE_APPCTX_ST_END+1] = { static char * generate_pseudo_uuid() { - char *uuid; - uint32_t rnd[4] = { 0, 0, 0, 0 }; - uint64_t last = 0; - int byte = 0; - uint8_t bits = 0; - unsigned int rand_max_bits = my_flsl(RAND_MAX); - - if ((uuid = calloc(1, 37)) == NULL) - return NULL; - - while (byte < 4) { - while (bits < 32) { - last |= (uint64_t)ha_random() << bits; - bits += rand_max_bits; - } - rnd[byte++] = last; - last >>= 32u; - bits -= 32; - } - snprintf(uuid, 37, "%8.8x-%4.4x-%4.4x-%4.4x-%12.12llx", - rnd[0], - rnd[1] & 0xFFFF, - ((rnd[1] >> 16u) & 0xFFF) | 0x4000, // highest 4 bits indicate the uuid version - (rnd[2] & 0x3FFF) | 0x8000, // the highest 2 bits indicate the UUID variant (10), - (long long)((rnd[2] >> 14u) | ((uint64_t) rnd[3] << 18u)) & 0xFFFFFFFFFFFFull - ); - return uuid; + ha_generate_uuid(&trash); + return trash.area; } diff --git a/src/sample.c b/src/sample.c index 088da418b8..d602887b8f 100644 --- a/src/sample.c +++ b/src/sample.c @@ -3328,30 +3328,7 @@ static int smp_check_uuid(struct arg *args, char **err) static int smp_fetch_uuid(const struct arg *args, struct sample *smp, const char *kw, void *private) { if (args[0].data.sint == 4 || !args[0].type) { - uint32_t rnd[4] = { 0, 0, 0, 0 }; - uint64_t last = 0; - int byte = 0; - uint8_t bits = 0; - unsigned int rand_max_bits = my_flsl(RAND_MAX); - - while (byte < 4) { - while (bits < 32) { - last |= (uint64_t)ha_random() << bits; - bits += rand_max_bits; - } - rnd[byte++] = last; - last >>= 32u; - bits -= 32; - } - - chunk_printf(&trash, "%8.8x-%4.4x-%4.4x-%4.4x-%12.12llx", - rnd[0], - rnd[1] & 0xFFFF, - ((rnd[1] >> 16u) & 0xFFF) | 0x4000, // highest 4 bits indicate the uuid version - (rnd[2] & 0x3FFF) | 0x8000, // the highest 2 bits indicate the UUID variant (10), - (long long)((rnd[2] >> 14u) | ((uint64_t) rnd[3] << 18u)) & 0xFFFFFFFFFFFFull - ); - + ha_generate_uuid(&trash); smp->data.type = SMP_T_STR; smp->flags = SMP_F_VOL_TEST | SMP_F_MAY_CHANGE; smp->data.u.str = trash; diff --git a/src/standard.c b/src/standard.c index 5ccf44776a..e0ea8328ef 100644 --- a/src/standard.c +++ b/src/standard.c @@ -4640,6 +4640,31 @@ void ha_random_jump96(uint32_t dist) } } +/* Generates an RFC4122 UUID into chunk which must be at least 37 + * bytes large. + */ +void ha_generate_uuid(struct buffer *output) +{ + uint32_t rnd[4]; + uint64_t last; + + last = ha_random64(); + rnd[0] = last; + rnd[1] = last >> 32; + + last = ha_random64(); + rnd[2] = last; + rnd[3] = last >> 32; + + chunk_printf(output, "%8.8x-%4.4x-%4.4x-%4.4x-%12.12llx", + rnd[0], + rnd[1] & 0xFFFF, + ((rnd[1] >> 16u) & 0xFFF) | 0x4000, // highest 4 bits indicate the uuid version + (rnd[2] & 0x3FFF) | 0x8000, // the highest 2 bits indicate the UUID variant (10), + (long long)((rnd[2] >> 14u) | ((uint64_t) rnd[3] << 18u)) & 0xFFFFFFFFFFFFull); +} + + /* * Local variables: * c-indent-level: 8 -- 2.39.5