/*
* Packet-oriented wrapper for non-AEAD modes
*/
int mbedtls_cipher_crypt( mbedtls_cipher_context_t *ctx,
const unsigned char *iv, size_t iv_len,
const unsigned char *input, size_t ilen,
unsigned char *output, size_t *olen )
{
int ret;
size_t finish_olen;
if( ( ret = mbedtls_cipher_set_iv( ctx, iv, iv_len ) ) != 0 )
return( ret );
if( ( ret = mbedtls_cipher_reset( ctx ) ) != 0 )
return( ret );
if( ( ret = mbedtls_cipher_update( ctx, input, ilen, output, olen ) ) != 0 )
return( ret );
if( ( ret = mbedtls_cipher_finish( ctx, output + *olen, &finish_olen ) ) != 0 )
return( ret );
*olen += finish_olen;
return( 0 );
}
static void cipher_decrypt(struct ssh_cipher_struct *cipher, void *in, void *out,
unsigned long len)
{
size_t outlen = 0;
int rc = 0;
size_t total_len = 0;
rc = mbedtls_cipher_update(&cipher->decrypt_ctx, in, len, out, &outlen);
if (rc != 0) {
SSH_LOG(SSH_LOG_WARNING, "mbedtls_cipher_update failed during decryption");
return;
}
total_len += outlen;
if (total_len == len) {
return;
}
rc = mbedtls_cipher_finish(&cipher->decrypt_ctx, (unsigned char *) out +
outlen, &outlen);
if (rc != 0) {
SSH_LOG(SSH_LOG_WARNING, "mbedtls_cipher_reset failed during decryption");
return;
}
total_len += outlen;
if (total_len != len) {
SSH_LOG(SSH_LOG_WARNING, "mbedtls_cipher_update: output size %zu for %zu",
outlen, len);
return;
}
}
static int cipher_context_update(cipher_ctx_t *ctx, uint8_t *output, int *olen,
const uint8_t *input, int ilen)
{
#ifdef USE_CRYPTO_APPLECC
cipher_cc_t *cc = &ctx->cc;
if (cc->valid == kCCContextValid) {
CCCryptorStatus ret;
ret = CCCryptorUpdate(cc->cryptor, input, ilen, output,
ilen, (size_t *)olen);
return (ret == kCCSuccess) ? 1 : 0;
}
#endif
cipher_evp_t *evp = &ctx->evp;
#if defined(USE_CRYPTO_OPENSSL)
return EVP_CipherUpdate(evp, (uint8_t *)output, olen,
(const uint8_t *)input, (size_t)ilen);
#elif defined(USE_CRYPTO_POLARSSL)
return !cipher_update(evp, (const uint8_t *)input, (size_t)ilen,
(uint8_t *)output, (size_t *)olen);
#elif defined(USE_CRYPTO_MBEDTLS)
return !mbedtls_cipher_update(evp, (const uint8_t *)input, (size_t)ilen,
(uint8_t *)output, (size_t *)olen);
#endif
}
/*
* KW-AD as defined in SP 800-38F section 6.2
* KWP-AD as defined in SP 800-38F section 6.3
*/
int mbedtls_nist_kw_unwrap( mbedtls_nist_kw_context *ctx,
mbedtls_nist_kw_mode_t mode,
const unsigned char *input, size_t in_len,
unsigned char *output, size_t *out_len, size_t out_size )
{
int ret = 0;
size_t i, olen;
unsigned char A[KW_SEMIBLOCK_LENGTH];
unsigned char diff, bad_padding = 0;
*out_len = 0;
if( out_size < in_len - KW_SEMIBLOCK_LENGTH )
{
return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
}
if( mode == MBEDTLS_KW_MODE_KW )
{
/*
* According to SP 800-38F Table 1, the ciphertext length for KW
* must be between 3 to 2^54 semiblocks inclusive.
*/
if( in_len < 24 ||
#if SIZE_MAX > 0x200000000000000
in_len > 0x200000000000000 ||
#endif
in_len % KW_SEMIBLOCK_LENGTH != 0 )
{
return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
}
ret = unwrap( ctx, input, in_len / KW_SEMIBLOCK_LENGTH,
A, output, out_len );
if( ret != 0 )
goto cleanup;
/* Check ICV in "constant-time" */
diff = mbedtls_nist_kw_safer_memcmp( NIST_KW_ICV1, A, KW_SEMIBLOCK_LENGTH );
if( diff != 0 )
{
ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
goto cleanup;
}
}
else if( mode == MBEDTLS_KW_MODE_KWP )
{
size_t padlen = 0;
uint32_t Plen;
/*
* According to SP 800-38F Table 1, the ciphertext length for KWP
* must be between 2 to 2^29 semiblocks inclusive.
*/
if( in_len < KW_SEMIBLOCK_LENGTH * 2 ||
#if SIZE_MAX > 0x100000000
in_len > 0x100000000 ||
#endif
in_len % KW_SEMIBLOCK_LENGTH != 0 )
{
return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
}
if( in_len == KW_SEMIBLOCK_LENGTH * 2 )
{
unsigned char outbuff[KW_SEMIBLOCK_LENGTH * 2];
ret = mbedtls_cipher_update( &ctx->cipher_ctx,
input, 16, outbuff, &olen );
if( ret != 0 )
goto cleanup;
memcpy( A, outbuff, KW_SEMIBLOCK_LENGTH );
memcpy( output, outbuff + KW_SEMIBLOCK_LENGTH, KW_SEMIBLOCK_LENGTH );
mbedtls_platform_zeroize( outbuff, sizeof( outbuff ) );
*out_len = KW_SEMIBLOCK_LENGTH;
}
else
{
/* in_len >= KW_SEMIBLOCK_LENGTH * 3 */
ret = unwrap( ctx, input, in_len / KW_SEMIBLOCK_LENGTH,
A, output, out_len );
if( ret != 0 )
goto cleanup;
}
/* Check ICV in "constant-time" */
diff = mbedtls_nist_kw_safer_memcmp( NIST_KW_ICV2, A, KW_SEMIBLOCK_LENGTH / 2 );
if( diff != 0 )
{
ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
}
GET_UINT32_BE( Plen, A, KW_SEMIBLOCK_LENGTH / 2 );
/*
* Plen is the length of the plaintext, when the input is valid.
* If Plen is larger than the plaintext and padding, padlen will be
* larger than 8, because of the type wrap around.
*/
padlen = in_len - KW_SEMIBLOCK_LENGTH - Plen;
if ( padlen > 7 )
{
padlen &= 7;
ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
}
/* Check padding in "constant-time" */
for( diff = 0, i = 0; i < KW_SEMIBLOCK_LENGTH; i++ )
{
if( i >= KW_SEMIBLOCK_LENGTH - padlen )
diff |= output[*out_len - KW_SEMIBLOCK_LENGTH + i];
else
bad_padding |= output[*out_len - KW_SEMIBLOCK_LENGTH + i];
}
if( diff != 0 )
{
ret = MBEDTLS_ERR_CIPHER_AUTH_FAILED;
}
if( ret != 0 )
{
goto cleanup;
}
memset( output + Plen, 0, padlen );
*out_len = Plen;
}
else
{
ret = MBEDTLS_ERR_CIPHER_FEATURE_UNAVAILABLE;
goto cleanup;
}
cleanup:
if( ret != 0 )
{
memset( output, 0, *out_len );
*out_len = 0;
}
mbedtls_platform_zeroize( &bad_padding, sizeof( bad_padding) );
mbedtls_platform_zeroize( &diff, sizeof( diff ) );
mbedtls_platform_zeroize( A, sizeof( A ) );
return( ret );
}
/*
* KW-AE as defined in SP 800-38F section 6.2
* KWP-AE as defined in SP 800-38F section 6.3
*/
int mbedtls_nist_kw_wrap( mbedtls_nist_kw_context *ctx,
mbedtls_nist_kw_mode_t mode,
const unsigned char *input, size_t in_len,
unsigned char *output, size_t *out_len, size_t out_size )
{
int ret = 0;
size_t semiblocks = 0;
size_t s;
size_t olen, padlen = 0;
uint64_t t = 0;
unsigned char outbuff[KW_SEMIBLOCK_LENGTH * 2];
unsigned char inbuff[KW_SEMIBLOCK_LENGTH * 2];
unsigned char *R2 = output + KW_SEMIBLOCK_LENGTH;
unsigned char *A = output;
*out_len = 0;
/*
* Generate the String to work on
*/
if( mode == MBEDTLS_KW_MODE_KW )
{
if( out_size < in_len + KW_SEMIBLOCK_LENGTH )
{
return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
}
/*
* According to SP 800-38F Table 1, the plaintext length for KW
* must be between 2 to 2^54-1 semiblocks inclusive.
*/
if( in_len < 16 ||
#if SIZE_MAX > 0x1FFFFFFFFFFFFF8
in_len > 0x1FFFFFFFFFFFFF8 ||
#endif
in_len % KW_SEMIBLOCK_LENGTH != 0 )
{
return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
}
memcpy( output, NIST_KW_ICV1, KW_SEMIBLOCK_LENGTH );
memmove( output + KW_SEMIBLOCK_LENGTH, input, in_len );
}
else
{
if( in_len % 8 != 0 )
{
padlen = ( 8 - ( in_len % 8 ) );
}
if( out_size < in_len + KW_SEMIBLOCK_LENGTH + padlen )
{
return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
}
/*
* According to SP 800-38F Table 1, the plaintext length for KWP
* must be between 1 and 2^32-1 octets inclusive.
*/
if( in_len < 1
#if SIZE_MAX > 0xFFFFFFFF
|| in_len > 0xFFFFFFFF
#endif
)
{
return( MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA );
}
memcpy( output, NIST_KW_ICV2, KW_SEMIBLOCK_LENGTH / 2 );
PUT_UINT32_BE( ( in_len & 0xffffffff ), output,
KW_SEMIBLOCK_LENGTH / 2 );
memcpy( output + KW_SEMIBLOCK_LENGTH, input, in_len );
memset( output + KW_SEMIBLOCK_LENGTH + in_len, 0, padlen );
}
semiblocks = ( ( in_len + padlen ) / KW_SEMIBLOCK_LENGTH ) + 1;
s = 6 * ( semiblocks - 1 );
if( mode == MBEDTLS_KW_MODE_KWP
&& in_len <= KW_SEMIBLOCK_LENGTH )
{
memcpy( inbuff, output, 16 );
ret = mbedtls_cipher_update( &ctx->cipher_ctx,
inbuff, 16, output, &olen );
if( ret != 0 )
goto cleanup;
}
else
{
/*
* Do the wrapping function W, as defined in RFC 3394 section 2.2.1
*/
if( semiblocks < MIN_SEMIBLOCKS_COUNT )
{
ret = MBEDTLS_ERR_CIPHER_BAD_INPUT_DATA;
goto cleanup;
}
/* Calculate intermediate values */
for( t = 1; t <= s; t++ )
{
memcpy( inbuff, A, KW_SEMIBLOCK_LENGTH );
memcpy( inbuff + KW_SEMIBLOCK_LENGTH, R2, KW_SEMIBLOCK_LENGTH );
ret = mbedtls_cipher_update( &ctx->cipher_ctx,
inbuff, 16, outbuff, &olen );
if( ret != 0 )
goto cleanup;
memcpy( A, outbuff, KW_SEMIBLOCK_LENGTH );
calc_a_xor_t( A, t );
memcpy( R2, outbuff + KW_SEMIBLOCK_LENGTH, KW_SEMIBLOCK_LENGTH );
R2 += KW_SEMIBLOCK_LENGTH;
if( R2 >= output + ( semiblocks * KW_SEMIBLOCK_LENGTH ) )
R2 = output + KW_SEMIBLOCK_LENGTH;
}
}
*out_len = semiblocks * KW_SEMIBLOCK_LENGTH;
cleanup:
if( ret != 0)
{
memset( output, 0, semiblocks * KW_SEMIBLOCK_LENGTH );
}
mbedtls_platform_zeroize( inbuff, KW_SEMIBLOCK_LENGTH * 2 );
mbedtls_platform_zeroize( outbuff, KW_SEMIBLOCK_LENGTH * 2 );
return( ret );
}
