From: Neil Horman Subject: Re: [PATCH 1/1] add fips(ansi_cprng) (v2) Date: Fri, 18 Sep 2009 14:34:46 -0400 Message-ID: <20090918183446.GB28540@hmsreliant.think-freely.org> References: <20090916160456.GC11163@hmsreliant.think-freely.org> <20090918183254.GA28540@hmsreliant.think-freely.org> Mime-Version: 1.0 Content-Type: text/plain; charset=us-ascii Cc: jarod@redhat.com, herbert@gondor.apana.org.au, davem@davemloft.net To: linux-crypto@vger.kernel.org Return-path: Received: from charlotte.tuxdriver.com ([70.61.120.58]:51536 "EHLO smtp.tuxdriver.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1757772AbZIRSes (ORCPT ); Fri, 18 Sep 2009 14:34:48 -0400 Content-Disposition: inline In-Reply-To: <20090918183254.GA28540@hmsreliant.think-freely.org> Sender: linux-crypto-owner@vger.kernel.org List-ID: Patch to add fips(ansi_cprng) alg, which is ansi_cprng plus a continuous test Signed-off-by: Neil Horman ansi_cprng.c | 79 ++++++++++++++++++++++++++++++++++++++++++++++++++++------- 1 file changed, 70 insertions(+), 9 deletions(-) diff --git a/crypto/ansi_cprng.c b/crypto/ansi_cprng.c index 3aa6e38..027176a 100644 --- a/crypto/ansi_cprng.c +++ b/crypto/ansi_cprng.c @@ -85,7 +85,7 @@ static void xor_vectors(unsigned char *in1, unsigned char *in2, * Returns DEFAULT_BLK_SZ bytes of random data per call * returns 0 if generation succeded, <0 if something went wrong */ -static int _get_more_prng_bytes(struct prng_context *ctx) +static int _get_more_prng_bytes(struct prng_context *ctx, int cont_test) { int i; unsigned char tmp[DEFAULT_BLK_SZ]; @@ -132,7 +132,7 @@ static int _get_more_prng_bytes(struct prng_context *ctx) */ if (!memcmp(ctx->rand_data, ctx->last_rand_data, DEFAULT_BLK_SZ)) { - if (fips_enabled) { + if (cont_test) { panic("cprng %p Failed repetition check!\n", ctx); } @@ -185,7 +185,8 @@ static int _get_more_prng_bytes(struct prng_context *ctx) } /* Our exported functions */ -static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx) +static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx, + int do_cont_test) { unsigned char *ptr = buf; unsigned int byte_count = (unsigned int)nbytes; @@ -220,7 +221,7 @@ static int get_prng_bytes(char *buf, size_t nbytes, struct prng_context *ctx) remainder: if (ctx->rand_data_valid == DEFAULT_BLK_SZ) { - if (_get_more_prng_bytes(ctx) < 0) { + if (_get_more_prng_bytes(ctx, do_cont_test) < 0) { memset(buf, 0, nbytes); err = -EINVAL; goto done; @@ -247,7 +248,7 @@ empty_rbuf: */ for (; byte_count >= DEFAULT_BLK_SZ; byte_count -= DEFAULT_BLK_SZ) { if (ctx->rand_data_valid == DEFAULT_BLK_SZ) { - if (_get_more_prng_bytes(ctx) < 0) { + if (_get_more_prng_bytes(ctx, do_cont_test) < 0) { memset(buf, 0, nbytes); err = -EINVAL; goto done; @@ -356,7 +357,15 @@ static int cprng_get_random(struct crypto_rng *tfm, u8 *rdata, { struct prng_context *prng = crypto_rng_ctx(tfm); - return get_prng_bytes(rdata, dlen, prng); + return get_prng_bytes(rdata, dlen, prng, 0); +} + +static int fips_cprng_get_random(struct crypto_rng *tfm, u8 *rdata, + unsigned int dlen) +{ + struct prng_context *prng = crypto_rng_ctx(tfm); + + return get_prng_bytes(rdata, dlen, prng, 1); } /* @@ -384,6 +393,26 @@ static int cprng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen) return 0; } +static int fips_cprng_reset(struct crypto_rng *tfm, u8 *seed, unsigned int slen) +{ + u8 rdata[DEFAULT_BLK_SZ]; + int rc; + + struct prng_context *prng = crypto_rng_ctx(tfm); + + rc = cprng_reset(tfm, seed, slen); + + if (!rc) + goto out; + + /* this primes our continuity test */ + rc = get_prng_bytes(rdata, DEFAULT_BLK_SZ, prng, 0); + prng->rand_data_valid = DEFAULT_BLK_SZ; + +out: + return rc; +} + static struct crypto_alg rng_alg = { .cra_name = "stdrng", .cra_driver_name = "ansi_cprng", @@ -404,19 +433,51 @@ static struct crypto_alg rng_alg = { } }; +#ifdef CONFIG_CRYPTO_FIPS +static struct crypto_alg fips_rng_alg = { + .cra_name = "fips(ansi_cprng)", + .cra_driver_name = "fips_ansi_cprng", + .cra_priority = 300, + .cra_flags = CRYPTO_ALG_TYPE_RNG, + .cra_ctxsize = sizeof(struct prng_context), + .cra_type = &crypto_rng_type, + .cra_module = THIS_MODULE, + .cra_list = LIST_HEAD_INIT(rng_alg.cra_list), + .cra_init = cprng_init, + .cra_exit = cprng_exit, + .cra_u = { + .rng = { + .rng_make_random = fips_cprng_get_random, + .rng_reset = fips_cprng_reset, + .seedsize = DEFAULT_PRNG_KSZ + 2*DEFAULT_BLK_SZ, + } + } +}; +#endif /* Module initalization */ static int __init prng_mod_init(void) { - if (fips_enabled) - rng_alg.cra_priority += 200; + int rc = 0; - return crypto_register_alg(&rng_alg); + rc = crypto_register_alg(&rng_alg); +#ifdef CONFIG_CRYPTO_FIPS + if (rc) + goto out; + + rc = crypto_register_alg(&fips_rng_alg); + +out: +#endif + return rc; } static void __exit prng_mod_fini(void) { crypto_unregister_alg(&rng_alg); +#ifdef CONFIG_CRYPTO_FIPS + crypto_unregister_alg(&fips_rng_alg); +#endif return; }