The patch titled Subject: prandom: introduce prandom_bytes() and prandom_bytes_state() has been added to the -mm tree. Its filename is prandom-introduce-prandom_bytes-and-prandom_bytes_state.patch Before you just go and hit "reply", please: a) Consider who else should be cc'ed b) Prefer to cc a suitable mailing list as well c) Ideally: find the original patch on the mailing list and do a reply-to-all to that, adding suitable additional cc's *** Remember to use Documentation/SubmitChecklist when testing your code *** The -mm tree is included into linux-next and is updated there every 3-4 working days ------------------------------------------------------ From: Akinobu Mita <akinobu.mita@xxxxxxxxx> Subject: prandom: introduce prandom_bytes() and prandom_bytes_state() Add functions to get the requested number of pseudo-random bytes. The difference from get_random_bytes() is that it generates pseudo-random numbers by prandom_u32(). It doesn't consume the entropy pool, and the sequence is reproducible if the same rnd_state is used. So it is suitable for generating random bytes for testing. Signed-off-by: Akinobu Mita <akinobu.mita@xxxxxxxxx> Cc: "Theodore Ts'o" <tytso@xxxxxxx> Cc: Artem Bityutskiy <dedekind1@xxxxxxxxx> Cc: Adrian Hunter <adrian.hunter@xxxxxxxxx> Cc: David Woodhouse <dwmw2@xxxxxxxxxxxxx> Cc: Eilon Greenstein <eilong@xxxxxxxxxxxx> Cc: David Laight <david.laight@xxxxxxxxxx> Cc: Michel Lespinasse <walken@xxxxxxxxxx> Cc: Robert Love <robert.w.love@xxxxxxxxx> Cc: Valdis Kletnieks <valdis.kletnieks@xxxxxx> Signed-off-by: Andrew Morton <akpm@xxxxxxxxxxxxxxxxxxxx> --- include/linux/random.h | 2 + lib/random32.c | 49 +++++++++++++++++++++++++++++++++++++++ 2 files changed, 51 insertions(+) diff -puN include/linux/random.h~prandom-introduce-prandom_bytes-and-prandom_bytes_state include/linux/random.h --- a/include/linux/random.h~prandom-introduce-prandom_bytes-and-prandom_bytes_state +++ a/include/linux/random.h @@ -26,6 +26,7 @@ unsigned int get_random_int(void); unsigned long randomize_range(unsigned long start, unsigned long end, unsigned long len); u32 prandom_u32(void); +void prandom_bytes(void *buf, int nbytes); void prandom_seed(u32 seed); /* @@ -36,6 +37,7 @@ void prandom_seed(u32 seed); #define srandom32(seed) prandom_seed(seed) u32 prandom_u32_state(struct rnd_state *); +void prandom_bytes_state(struct rnd_state *state, void *buf, int nbytes); /* * Handle minimum values for seeds diff -puN lib/random32.c~prandom-introduce-prandom_bytes-and-prandom_bytes_state lib/random32.c --- a/lib/random32.c~prandom-introduce-prandom_bytes-and-prandom_bytes_state +++ a/lib/random32.c @@ -77,6 +77,55 @@ u32 prandom_u32(void) } EXPORT_SYMBOL(prandom_u32); +/* + * prandom_bytes_state - get the requested number of pseudo-random bytes + * + * @state: pointer to state structure holding seeded state. + * @buf: where to copy the pseudo-random bytes to + * @bytes: the requested number of bytes + * + * This is used for pseudo-randomness with no outside seeding. + * For more random results, use prandom_bytes(). + */ +void prandom_bytes_state(struct rnd_state *state, void *buf, int bytes) +{ + unsigned char *p = buf; + int i; + + for (i = 0; i < round_down(bytes, sizeof(u32)); i += sizeof(u32)) { + u32 random = prandom_u32_state(state); + int j; + + for (j = 0; j < sizeof(u32); j++) { + p[i + j] = random; + random >>= BITS_PER_BYTE; + } + } + if (i < bytes) { + u32 random = prandom_u32_state(state); + + for (; i < bytes; i++) { + p[i] = random; + random >>= BITS_PER_BYTE; + } + } +} +EXPORT_SYMBOL(prandom_bytes_state); + +/** + * prandom_bytes - get the requested number of pseudo-random bytes + * @buf: where to copy the pseudo-random bytes to + * @bytes: the requested number of bytes + */ +void prandom_bytes(void *buf, int bytes) +{ + struct rnd_state *state = &get_cpu_var(net_rand_state); + + prandom_bytes_state(state, buf, bytes); + put_cpu_var(state); +} +EXPORT_SYMBOL(prandom_bytes); + /** * prandom_seed - add entropy to pseudo random number generator * @seed: seed value _ Patches currently in -mm which might be from akinobu.mita@xxxxxxxxx are linux-next.patch random32-rename-random32-to-prandom.patch prandom-introduce-prandom_bytes-and-prandom_bytes_state.patch bnx2x-use-prandom_bytes.patch mtd-nandsim-use-prandom_bytes.patch ubifs-use-prandom_bytes.patch mtd-mtd_nandecctest-use-prandom_bytes-instead-of-get_random_bytes.patch mtd-mtd_oobtest-convert-to-use-prandom-library.patch mtd-mtd_pagetest-convert-to-use-prandom-library.patch mtd-mtd_speedtest-use-prandom_bytes.patch mtd-mtd_subpagetest-convert-to-use-prandom-library.patch mtd-mtd_stresstest-use-prandom_bytes.patch -- To unsubscribe from this list: send the line "unsubscribe mm-commits" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html