Fix crypt mode configuration. Validate parameters in chunked input functions.

Signed-off-by: Mateusz Starzyk <mateusz.starzyk@mobica.com>
This commit is contained in:
Mateusz Starzyk 2021-07-09 12:44:07 +02:00
parent 6a15bcf61b
commit 05e92d67bb

View File

@ -52,8 +52,6 @@
#define CCM_VALIDATE( cond ) \
MBEDTLS_INTERNAL_VALIDATE( cond )
#define CCM_ENCRYPT 0
#define CCM_DECRYPT 1
/*
* Initialize context
@ -174,6 +172,10 @@ static int mbedtls_ccm_calculate_first_block(mbedtls_ccm_context *ctx)
if( !(ctx->state & CCM_STATE__STARTED) || !(ctx->state & CCM_STATE__LENGHTS_SET) )
return 0;
if( ctx->tag_len == 0 && \
( ctx->mode == MBEDTLS_CCM_ENCRYPT || ctx->mode == MBEDTLS_CCM_DECRYPT ) )
return( MBEDTLS_ERR_CCM_BAD_INPUT );
/*
* First block B_0:
* 0 .. 0 flags
@ -210,6 +212,13 @@ int mbedtls_ccm_starts( mbedtls_ccm_context *ctx,
const unsigned char *iv,
size_t iv_len )
{
CCM_VALIDATE_RET( ctx != NULL );
CCM_VALIDATE_RET( iv != NULL );
CCM_VALIDATE_RET( mode == MBEDTLS_CCM_DECRYPT || \
mode == MBEDTLS_CCM_STAR_DECRYPT || \
mode == MBEDTLS_CCM_ENCRYPT || \
mode == MBEDTLS_CCM_STAR_ENCRYPT );
/* Also implies q is within bounds */
if( iv_len < 7 || iv_len > 13 )
return( MBEDTLS_ERR_CCM_BAD_INPUT );
@ -252,6 +261,8 @@ int mbedtls_ccm_set_lengths( mbedtls_ccm_context *ctx,
size_t plaintext_len,
size_t tag_len )
{
CCM_VALIDATE_RET( ctx != NULL );
/*
* Check length requirements: SP800-38C A.1
* Additional requirement: a < 2^16 - 2^8 to simplify the code.
@ -283,6 +294,8 @@ int mbedtls_ccm_update_ad( mbedtls_ccm_context *ctx,
const unsigned char *add,
size_t add_len )
{
CCM_VALIDATE_RET( ctx->add_len == 0 || add != NULL );
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char i;
size_t olen, use_len, offset;
@ -331,6 +344,9 @@ int mbedtls_ccm_update( mbedtls_ccm_context *ctx,
unsigned char *output, size_t output_size,
size_t *output_len )
{
CCM_VALIDATE_RET( ctx->plaintext_len == 0 || input != NULL );
CCM_VALIDATE_RET( ctx->plaintext_len == 0 || output != NULL );
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char i;
size_t use_len, offset, olen;
@ -359,7 +375,8 @@ int mbedtls_ccm_update( mbedtls_ccm_context *ctx,
if( use_len + offset == 16 || ctx->processed == ctx->plaintext_len )
{
if( ctx->mode == CCM_ENCRYPT )
if( ctx->mode == MBEDTLS_CCM_ENCRYPT || \
ctx->mode == MBEDTLS_CCM_STAR_ENCRYPT )
{
UPDATE_CBC_MAC;
ret = mbedtls_ccm_crypt( ctx, 0, use_len, ctx->b, output );
@ -368,7 +385,8 @@ int mbedtls_ccm_update( mbedtls_ccm_context *ctx,
memset( ctx->b, 0, 16 );
}
if( ctx->mode == CCM_DECRYPT )
if( ctx->mode == MBEDTLS_CCM_DECRYPT || \
ctx->mode == MBEDTLS_CCM_STAR_DECRYPT )
{
ret = mbedtls_ccm_crypt( ctx, 0, use_len, ctx->b, output );
if( ret != 0 )
@ -402,6 +420,7 @@ int mbedtls_ccm_finish( mbedtls_ccm_context *ctx,
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char i;
CCM_VALIDATE_RET( tag_len == 0 || tag != NULL );
/*
* Authentication: reset counter and crypt/mask internal tag
*/
@ -457,13 +476,7 @@ int mbedtls_ccm_star_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *input, unsigned char *output,
unsigned char *tag, size_t tag_len )
{
CCM_VALIDATE_RET( ctx != NULL );
CCM_VALIDATE_RET( iv != NULL );
CCM_VALIDATE_RET( add_len == 0 || add != NULL );
CCM_VALIDATE_RET( length == 0 || input != NULL );
CCM_VALIDATE_RET( length == 0 || output != NULL );
CCM_VALIDATE_RET( tag_len == 0 || tag != NULL );
return( ccm_auth_crypt( ctx, CCM_ENCRYPT, length, iv, iv_len,
return( ccm_auth_crypt( ctx, MBEDTLS_CCM_STAR_ENCRYPT, length, iv, iv_len,
add, add_len, input, output, tag, tag_len ) );
}
@ -473,17 +486,25 @@ int mbedtls_ccm_encrypt_and_tag( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *input, unsigned char *output,
unsigned char *tag, size_t tag_len )
{
CCM_VALIDATE_RET( ctx != NULL );
CCM_VALIDATE_RET( iv != NULL );
CCM_VALIDATE_RET( add_len == 0 || add != NULL );
CCM_VALIDATE_RET( length == 0 || input != NULL );
CCM_VALIDATE_RET( length == 0 || output != NULL );
CCM_VALIDATE_RET( tag_len == 0 || tag != NULL );
if( tag_len == 0 )
return( MBEDTLS_ERR_CCM_BAD_INPUT );
return( ccm_auth_crypt( ctx, MBEDTLS_CCM_ENCRYPT, length, iv, iv_len,
add, add_len, input, output, tag, tag_len ) );
}
return( mbedtls_ccm_star_encrypt_and_tag( ctx, length, iv, iv_len, add,
add_len, input, output, tag, tag_len ) );
static int mbedtls_ccm_compare_tags(const unsigned char *tag1, const unsigned char *tag2, size_t tag_len)
{
unsigned char i;
int diff;
/* Check tag in "constant-time" */
for( diff = 0, i = 0; i < tag_len; i++ )
diff |= tag1[i] ^ tag2[i];
if( diff != 0 )
{
return( MBEDTLS_ERR_CCM_AUTH_FAILED );
}
return( 0 );
}
/*
@ -497,31 +518,18 @@ int mbedtls_ccm_star_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
{
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char check_tag[16];
unsigned char i;
int diff;
CCM_VALIDATE_RET( ctx != NULL );
CCM_VALIDATE_RET( iv != NULL );
CCM_VALIDATE_RET( add_len == 0 || add != NULL );
CCM_VALIDATE_RET( length == 0 || input != NULL );
CCM_VALIDATE_RET( length == 0 || output != NULL );
CCM_VALIDATE_RET( tag_len == 0 || tag != NULL );
if( ( ret = ccm_auth_crypt( ctx, CCM_DECRYPT, length,
if( ( ret = ccm_auth_crypt( ctx, MBEDTLS_CCM_STAR_DECRYPT, length,
iv, iv_len, add, add_len,
input, output, check_tag, tag_len ) ) != 0 )
{
return( ret );
}
/* Check tag in "constant-time" */
for( diff = 0, i = 0; i < tag_len; i++ )
diff |= tag[i] ^ check_tag[i];
if( diff != 0 )
if( ( ret = mbedtls_ccm_compare_tags( tag, check_tag, tag_len ) ) != 0 )
{
mbedtls_platform_zeroize( output, length );
return( MBEDTLS_ERR_CCM_AUTH_FAILED );
return( ret );
}
return( 0 );
@ -533,18 +541,23 @@ int mbedtls_ccm_auth_decrypt( mbedtls_ccm_context *ctx, size_t length,
const unsigned char *input, unsigned char *output,
const unsigned char *tag, size_t tag_len )
{
CCM_VALIDATE_RET( ctx != NULL );
CCM_VALIDATE_RET( iv != NULL );
CCM_VALIDATE_RET( add_len == 0 || add != NULL );
CCM_VALIDATE_RET( length == 0 || input != NULL );
CCM_VALIDATE_RET( length == 0 || output != NULL );
CCM_VALIDATE_RET( tag_len == 0 || tag != NULL );
int ret = MBEDTLS_ERR_ERROR_CORRUPTION_DETECTED;
unsigned char check_tag[16];
if( tag_len == 0 )
return( MBEDTLS_ERR_CCM_BAD_INPUT );
if( ( ret = ccm_auth_crypt( ctx, MBEDTLS_CCM_DECRYPT, length,
iv, iv_len, add, add_len,
input, output, check_tag, tag_len ) ) != 0 )
{
return( ret );
}
return( mbedtls_ccm_star_auth_decrypt( ctx, length, iv, iv_len, add,
add_len, input, output, tag, tag_len ) );
if( ( ret = mbedtls_ccm_compare_tags( tag, check_tag, tag_len ) ) != 0 )
{
mbedtls_platform_zeroize( output, length );
return( ret );
}
return( 0 );
}
#endif /* !MBEDTLS_CCM_ALT */