diff options
Diffstat (limited to 'thirdparty/mbedtls/library/ctr_drbg.c')
| -rw-r--r-- | thirdparty/mbedtls/library/ctr_drbg.c | 175 |
1 files changed, 123 insertions, 52 deletions
diff --git a/thirdparty/mbedtls/library/ctr_drbg.c b/thirdparty/mbedtls/library/ctr_drbg.c index d0e5ba862d..fb121575bb 100644 --- a/thirdparty/mbedtls/library/ctr_drbg.c +++ b/thirdparty/mbedtls/library/ctr_drbg.c @@ -66,6 +66,18 @@ void mbedtls_ctr_drbg_init( mbedtls_ctr_drbg_context *ctx ) * Non-public function wrapped by mbedtls_ctr_drbg_seed(). Necessary to allow * NIST tests to succeed (which require known length fixed entropy) */ +/* CTR_DRBG_Instantiate with derivation function (SP 800-90A §10.2.1.3.2) + * mbedtls_ctr_drbg_seed_entropy_len(ctx, f_entropy, p_entropy, + * custom, len, entropy_len) + * implements + * CTR_DRBG_Instantiate(entropy_input, nonce, personalization_string, + * security_strength) -> initial_working_state + * with inputs + * custom[:len] = nonce || personalization_string + * where entropy_input comes from f_entropy for entropy_len bytes + * and with outputs + * ctx = initial_working_state + */ int mbedtls_ctr_drbg_seed_entropy_len( mbedtls_ctr_drbg_context *ctx, int (*f_entropy)(void *, unsigned char *, size_t), @@ -256,6 +268,14 @@ exit: return( ret ); } +/* CTR_DRBG_Update (SP 800-90A §10.2.1.2) + * ctr_drbg_update_internal(ctx, provided_data) + * implements + * CTR_DRBG_Update(provided_data, Key, V) + * with inputs and outputs + * ctx->aes_ctx = Key + * ctx->counter = V + */ static int ctr_drbg_update_internal( mbedtls_ctr_drbg_context *ctx, const unsigned char data[MBEDTLS_CTR_DRBG_SEEDLEN] ) { @@ -279,9 +299,7 @@ static int ctr_drbg_update_internal( mbedtls_ctr_drbg_context *ctx, * Crypt counter block */ if( ( ret = mbedtls_aes_crypt_ecb( &ctx->aes_ctx, MBEDTLS_AES_ENCRYPT, ctx->counter, p ) ) != 0 ) - { - return( ret ); - } + goto exit; p += MBEDTLS_CTR_DRBG_BLOCKSIZE; } @@ -293,31 +311,71 @@ static int ctr_drbg_update_internal( mbedtls_ctr_drbg_context *ctx, * Update key and counter */ if( ( ret = mbedtls_aes_setkey_enc( &ctx->aes_ctx, tmp, MBEDTLS_CTR_DRBG_KEYBITS ) ) != 0 ) - { - return( ret ); - } + goto exit; memcpy( ctx->counter, tmp + MBEDTLS_CTR_DRBG_KEYSIZE, MBEDTLS_CTR_DRBG_BLOCKSIZE ); - return( 0 ); +exit: + mbedtls_platform_zeroize( tmp, sizeof( tmp ) ); + return( ret ); } -void mbedtls_ctr_drbg_update( mbedtls_ctr_drbg_context *ctx, - const unsigned char *additional, size_t add_len ) +/* CTR_DRBG_Instantiate with derivation function (SP 800-90A §10.2.1.3.2) + * mbedtls_ctr_drbg_update(ctx, additional, add_len) + * implements + * CTR_DRBG_Instantiate(entropy_input, nonce, personalization_string, + * security_strength) -> initial_working_state + * with inputs + * ctx->counter = all-bits-0 + * ctx->aes_ctx = context from all-bits-0 key + * additional[:add_len] = entropy_input || nonce || personalization_string + * and with outputs + * ctx = initial_working_state + */ +int mbedtls_ctr_drbg_update_ret( mbedtls_ctr_drbg_context *ctx, + const unsigned char *additional, + size_t add_len ) { unsigned char add_input[MBEDTLS_CTR_DRBG_SEEDLEN]; + int ret; - if( add_len > 0 ) - { - /* MAX_INPUT would be more logical here, but we have to match - * block_cipher_df()'s limits since we can't propagate errors */ - if( add_len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT ) - add_len = MBEDTLS_CTR_DRBG_MAX_SEED_INPUT; + if( add_len == 0 ) + return( 0 ); - block_cipher_df( add_input, additional, add_len ); - ctr_drbg_update_internal( ctx, add_input ); - } + if( ( ret = block_cipher_df( add_input, additional, add_len ) ) != 0 ) + goto exit; + if( ( ret = ctr_drbg_update_internal( ctx, add_input ) ) != 0 ) + goto exit; + +exit: + mbedtls_platform_zeroize( add_input, sizeof( add_input ) ); + return( ret ); } +#if !defined(MBEDTLS_DEPRECATED_REMOVED) +void mbedtls_ctr_drbg_update( mbedtls_ctr_drbg_context *ctx, + const unsigned char *additional, + size_t add_len ) +{ + /* MAX_INPUT would be more logical here, but we have to match + * block_cipher_df()'s limits since we can't propagate errors */ + if( add_len > MBEDTLS_CTR_DRBG_MAX_SEED_INPUT ) + add_len = MBEDTLS_CTR_DRBG_MAX_SEED_INPUT; + (void) mbedtls_ctr_drbg_update_ret( ctx, additional, add_len ); +} +#endif /* MBEDTLS_DEPRECATED_REMOVED */ + +/* CTR_DRBG_Reseed with derivation function (SP 800-90A §10.2.1.4.2) + * mbedtls_ctr_drbg_reseed(ctx, additional, len) + * implements + * CTR_DRBG_Reseed(working_state, entropy_input, additional_input) + * -> new_working_state + * with inputs + * ctx contains working_state + * additional[:len] = additional_input + * and entropy_input comes from calling ctx->f_entropy + * and with output + * ctx contains new_working_state + */ int mbedtls_ctr_drbg_reseed( mbedtls_ctr_drbg_context *ctx, const unsigned char *additional, size_t len ) { @@ -355,22 +413,39 @@ int mbedtls_ctr_drbg_reseed( mbedtls_ctr_drbg_context *ctx, * Reduce to 384 bits */ if( ( ret = block_cipher_df( seed, seed, seedlen ) ) != 0 ) - { - return( ret ); - } + goto exit; /* * Update state */ if( ( ret = ctr_drbg_update_internal( ctx, seed ) ) != 0 ) - { - return( ret ); - } + goto exit; ctx->reseed_counter = 1; - return( 0 ); +exit: + mbedtls_platform_zeroize( seed, sizeof( seed ) ); + return( ret ); } +/* CTR_DRBG_Generate with derivation function (SP 800-90A §10.2.1.5.2) + * mbedtls_ctr_drbg_random_with_add(ctx, output, output_len, additional, add_len) + * implements + * CTR_DRBG_Reseed(working_state, entropy_input, additional[:add_len]) + * -> working_state_after_reseed + * if required, then + * CTR_DRBG_Generate(working_state_after_reseed, + * requested_number_of_bits, additional_input) + * -> status, returned_bits, new_working_state + * with inputs + * ctx contains working_state + * requested_number_of_bits = 8 * output_len + * additional[:add_len] = additional_input + * and entropy_input comes from calling ctx->f_entropy + * and with outputs + * status = SUCCESS (this function does the reseed internally) + * returned_bits = output[:output_len] + * ctx contains new_working_state + */ int mbedtls_ctr_drbg_random_with_add( void *p_rng, unsigned char *output, size_t output_len, const unsigned char *additional, size_t add_len ) @@ -404,13 +479,9 @@ int mbedtls_ctr_drbg_random_with_add( void *p_rng, if( add_len > 0 ) { if( ( ret = block_cipher_df( add_input, additional, add_len ) ) != 0 ) - { - return( ret ); - } + goto exit; if( ( ret = ctr_drbg_update_internal( ctx, add_input ) ) != 0 ) - { - return( ret ); - } + goto exit; } while( output_len > 0 ) @@ -426,9 +497,7 @@ int mbedtls_ctr_drbg_random_with_add( void *p_rng, * Crypt counter block */ if( ( ret = mbedtls_aes_crypt_ecb( &ctx->aes_ctx, MBEDTLS_AES_ENCRYPT, ctx->counter, tmp ) ) != 0 ) - { - return( ret ); - } + goto exit; use_len = ( output_len > MBEDTLS_CTR_DRBG_BLOCKSIZE ) ? MBEDTLS_CTR_DRBG_BLOCKSIZE : output_len; @@ -441,12 +510,13 @@ int mbedtls_ctr_drbg_random_with_add( void *p_rng, } if( ( ret = ctr_drbg_update_internal( ctx, add_input ) ) != 0 ) - { - return( ret ); - } + goto exit; ctx->reseed_counter++; +exit: + mbedtls_platform_zeroize( add_input, sizeof( add_input ) ); + mbedtls_platform_zeroize( tmp, sizeof( tmp ) ); return( 0 ); } @@ -498,35 +568,36 @@ exit: int mbedtls_ctr_drbg_update_seed_file( mbedtls_ctr_drbg_context *ctx, const char *path ) { int ret = 0; - FILE *f; + FILE *f = NULL; size_t n; unsigned char buf[ MBEDTLS_CTR_DRBG_MAX_INPUT ]; + unsigned char c; if( ( f = fopen( path, "rb" ) ) == NULL ) return( MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR ); - fseek( f, 0, SEEK_END ); - n = (size_t) ftell( f ); - fseek( f, 0, SEEK_SET ); - - if( n > MBEDTLS_CTR_DRBG_MAX_INPUT ) + n = fread( buf, 1, sizeof( buf ), f ); + if( fread( &c, 1, 1, f ) != 0 ) { - fclose( f ); - return( MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG ); + ret = MBEDTLS_ERR_CTR_DRBG_INPUT_TOO_BIG; + goto exit; } - - if( fread( buf, 1, n, f ) != n ) + if( n == 0 || ferror( f ) ) + { ret = MBEDTLS_ERR_CTR_DRBG_FILE_IO_ERROR; - else - mbedtls_ctr_drbg_update( ctx, buf, n ); - + goto exit; + } fclose( f ); + f = NULL; - mbedtls_platform_zeroize( buf, sizeof( buf ) ); + ret = mbedtls_ctr_drbg_update_ret( ctx, buf, n ); +exit: + mbedtls_platform_zeroize( buf, sizeof( buf ) ); + if( f != NULL ) + fclose( f ); if( ret != 0 ) return( ret ); - return( mbedtls_ctr_drbg_write_seed_file( ctx, path ) ); } #endif /* MBEDTLS_FS_IO */ |