diff options
Diffstat (limited to 'thirdparty/mbedtls/library/hmac_drbg.c')
-rw-r--r-- | thirdparty/mbedtls/library/hmac_drbg.c | 25 |
1 files changed, 14 insertions, 11 deletions
diff --git a/thirdparty/mbedtls/library/hmac_drbg.c b/thirdparty/mbedtls/library/hmac_drbg.c index 50d88bd54b..284c9b4e96 100644 --- a/thirdparty/mbedtls/library/hmac_drbg.c +++ b/thirdparty/mbedtls/library/hmac_drbg.c @@ -273,16 +273,19 @@ int mbedtls_hmac_drbg_seed( mbedtls_hmac_drbg_context *ctx, ctx->reseed_interval = MBEDTLS_HMAC_DRBG_RESEED_INTERVAL; - /* - * See SP800-57 5.6.1 (p. 65-66) for the security strength provided by - * each hash function, then according to SP800-90A rev1 10.1 table 2, - * min_entropy_len (in bits) is security_strength. - * - * (This also matches the sizes used in the NIST test vectors.) - */ - ctx->entropy_len = md_size <= 20 ? 16 : /* 160-bits hash -> 128 bits */ - md_size <= 28 ? 24 : /* 224-bits hash -> 192 bits */ - 32; /* better (256+) -> 256 bits */ + if( ctx->entropy_len == 0 ) + { + /* + * See SP800-57 5.6.1 (p. 65-66) for the security strength provided by + * each hash function, then according to SP800-90A rev1 10.1 table 2, + * min_entropy_len (in bits) is security_strength. + * + * (This also matches the sizes used in the NIST test vectors.) + */ + ctx->entropy_len = md_size <= 20 ? 16 : /* 160-bits hash -> 128 bits */ + md_size <= 28 ? 24 : /* 224-bits hash -> 192 bits */ + 32; /* better (256+) -> 256 bits */ + } if( ( ret = hmac_drbg_reseed_core( ctx, custom, len, 1 /* add nonce */ ) ) != 0 ) @@ -303,7 +306,7 @@ void mbedtls_hmac_drbg_set_prediction_resistance( mbedtls_hmac_drbg_context *ctx } /* - * Set entropy length grabbed for reseeds + * Set entropy length grabbed for seeding */ void mbedtls_hmac_drbg_set_entropy_len( mbedtls_hmac_drbg_context *ctx, size_t len ) { |