yuzu/mbedtls
1
0
Fork 0
mirror of https://github.com/yuzu-emu/mbedtls.git synced 2024-10-19 10:11:24 +00:00
Code Issues Packages Projects Releases Wiki Activity
mbedtls/library/psa_crypto_cipher.c
Gilles Peskine 8890f64338 Add ARIA to the PSA API 
Use the encoding from an upcoming version of the specification.

Add as much (or as little) testing as is currently present for Camellia.

Signed-off-by: Gilles Peskine <Gilles.Peskine@arm.com>
2021-10-08 18:28:15 +02:00

745 lines
25 KiB
C
Raw Blame History

/*
* PSA cipher driver entry points
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0
*
* Licensed under the Apache License, Version 2.0 (the "License"); you may
* not use this file except in compliance with the License.
* You may obtain a copy of the License at
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
* WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#include "common.h"
#if defined(MBEDTLS_PSA_CRYPTO_C)
#include <psa_crypto_cipher.h>
#include "psa_crypto_core.h"
#include "psa_crypto_random_impl.h"
#include "mbedtls/cipher.h"
#include "mbedtls/error.h"
#include <string.h>
#if ( defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_DES) || \
( defined(PSA_CRYPTO_DRIVER_TEST) && \
defined(MBEDTLS_PSA_ACCEL_KEY_TYPE_DES) ) )
#define BUILTIN_KEY_TYPE_DES 1
#endif
#if ( defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_NO_PADDING) || \
( defined(PSA_CRYPTO_DRIVER_TEST) && \
defined(MBEDTLS_PSA_ACCEL_ALG_CBC_NO_PADDING) ) )
#define BUILTIN_ALG_CBC_NO_PADDING 1
#endif
#if ( defined(MBEDTLS_PSA_BUILTIN_ALG_CBC_PKCS7) || \
( defined(PSA_CRYPTO_DRIVER_TEST) && \
defined(MBEDTLS_PSA_ACCEL_ALG_CBC_PKCS7) ) )
#define BUILTIN_ALG_CBC_PKCS7 1
#endif
#if ( defined(MBEDTLS_PSA_BUILTIN_KEY_TYPE_CHACHA20) || \
( defined(PSA_CRYPTO_DRIVER_TEST) && \
defined(MBEDTLS_PSA_ACCEL_KEY_TYPE_CHACHA20) ) )
#define BUILTIN_KEY_TYPE_CHACHA20 1
#endif
const mbedtls_cipher_info_t *mbedtls_cipher_info_from_psa(
psa_algorithm_t alg,
psa_key_type_t key_type,
size_t key_bits,
mbedtls_cipher_id_t* cipher_id )
{
mbedtls_cipher_mode_t mode;
mbedtls_cipher_id_t cipher_id_tmp;
if( PSA_ALG_IS_AEAD( alg ) )
alg = PSA_ALG_AEAD_WITH_SHORTENED_TAG( alg, 0 );
if( PSA_ALG_IS_CIPHER( alg ) || PSA_ALG_IS_AEAD( alg ) )
{
switch( alg )
{
case PSA_ALG_STREAM_CIPHER:
mode = MBEDTLS_MODE_STREAM;
break;
case PSA_ALG_CTR:
mode = MBEDTLS_MODE_CTR;
break;
case PSA_ALG_CFB:
mode = MBEDTLS_MODE_CFB;
break;
case PSA_ALG_OFB:
mode = MBEDTLS_MODE_OFB;
break;
case PSA_ALG_ECB_NO_PADDING:
mode = MBEDTLS_MODE_ECB;
break;
case PSA_ALG_CBC_NO_PADDING:
mode = MBEDTLS_MODE_CBC;
break;
case PSA_ALG_CBC_PKCS7:
mode = MBEDTLS_MODE_CBC;
break;
case PSA_ALG_AEAD_WITH_SHORTENED_TAG( PSA_ALG_CCM, 0 ):
mode = MBEDTLS_MODE_CCM;
break;
case PSA_ALG_AEAD_WITH_SHORTENED_TAG( PSA_ALG_GCM, 0 ):
mode = MBEDTLS_MODE_GCM;
break;
case PSA_ALG_AEAD_WITH_SHORTENED_TAG( PSA_ALG_CHACHA20_POLY1305, 0 ):
mode = MBEDTLS_MODE_CHACHAPOLY;
break;
default:
return( NULL );
}
}
else if( alg == PSA_ALG_CMAC )
mode = MBEDTLS_MODE_ECB;
else
return( NULL );
switch( key_type )
{
case PSA_KEY_TYPE_AES:
cipher_id_tmp = MBEDTLS_CIPHER_ID_AES;
break;
case PSA_KEY_TYPE_ARIA:
cipher_id_tmp = MBEDTLS_CIPHER_ID_ARIA;
break;
case PSA_KEY_TYPE_DES:
/* key_bits is 64 for Single-DES, 128 for two-key Triple-DES,
* and 192 for three-key Triple-DES. */
if( key_bits == 64 )
cipher_id_tmp = MBEDTLS_CIPHER_ID_DES;
else
cipher_id_tmp = MBEDTLS_CIPHER_ID_3DES;
/* mbedtls doesn't recognize two-key Triple-DES as an algorithm,
* but two-key Triple-DES is functionally three-key Triple-DES
* with K1=K3, so that's how we present it to mbedtls. */
if( key_bits == 128 )
key_bits = 192;
break;
case PSA_KEY_TYPE_CAMELLIA:
cipher_id_tmp = MBEDTLS_CIPHER_ID_CAMELLIA;
break;
case PSA_KEY_TYPE_ARC4:
cipher_id_tmp = MBEDTLS_CIPHER_ID_ARC4;
break;
case PSA_KEY_TYPE_CHACHA20:
cipher_id_tmp = MBEDTLS_CIPHER_ID_CHACHA20;
break;
default:
return( NULL );
}
if( cipher_id != NULL )
*cipher_id = cipher_id_tmp;
return( mbedtls_cipher_info_from_values( cipher_id_tmp,
(int) key_bits, mode ) );
}
#if defined(MBEDTLS_PSA_BUILTIN_CIPHER) || defined(PSA_CRYPTO_DRIVER_TEST)
static psa_status_t cipher_setup(
mbedtls_psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg,
mbedtls_operation_t cipher_operation )
{
int ret = 0;
size_t key_bits;
const mbedtls_cipher_info_t *cipher_info = NULL;
psa_key_type_t key_type = attributes->core.type;
(void)key_buffer_size;
mbedtls_cipher_init( &operation->ctx.cipher );
operation->alg = alg;
key_bits = attributes->core.bits;
cipher_info = mbedtls_cipher_info_from_psa( alg, key_type,
key_bits, NULL );
if( cipher_info == NULL )
return( PSA_ERROR_NOT_SUPPORTED );
ret = mbedtls_cipher_setup( &operation->ctx.cipher, cipher_info );
if( ret != 0 )
goto exit;
#if defined(BUILTIN_KEY_TYPE_DES)
if( key_type == PSA_KEY_TYPE_DES && key_bits == 128 )
{
/* Two-key Triple-DES is 3-key Triple-DES with K1=K3 */
uint8_t keys[24];
memcpy( keys, key_buffer, 16 );
memcpy( keys + 16, key_buffer, 8 );
ret = mbedtls_cipher_setkey( &operation->ctx.cipher,
keys,
192, cipher_operation );
}
else
#endif
{
ret = mbedtls_cipher_setkey( &operation->ctx.cipher, key_buffer,
(int) key_bits, cipher_operation );
}
if( ret != 0 )
goto exit;
#if defined(BUILTIN_ALG_CBC_NO_PADDING) || \
defined(BUILTIN_ALG_CBC_PKCS7)
switch( alg )
{
case PSA_ALG_CBC_NO_PADDING:
ret = mbedtls_cipher_set_padding_mode( &operation->ctx.cipher,
MBEDTLS_PADDING_NONE );
break;
case PSA_ALG_CBC_PKCS7:
ret = mbedtls_cipher_set_padding_mode( &operation->ctx.cipher,
MBEDTLS_PADDING_PKCS7 );
break;
default:
/* The algorithm doesn't involve padding. */
ret = 0;
break;
}
if( ret != 0 )
goto exit;
#endif /* BUILTIN_ALG_CBC_NO_PADDING || BUILTIN_ALG_CBC_PKCS7 */
operation->block_length = ( PSA_ALG_IS_STREAM_CIPHER( alg ) ? 1 :
PSA_BLOCK_CIPHER_BLOCK_LENGTH( key_type ) );
operation->iv_length = PSA_CIPHER_IV_LENGTH( key_type, alg );
exit:
return( mbedtls_to_psa_error( ret ) );
}
static psa_status_t cipher_encrypt_setup(
mbedtls_psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_setup( operation, attributes,
key_buffer, key_buffer_size,
alg, MBEDTLS_ENCRYPT ) );
}
static psa_status_t cipher_decrypt_setup(
mbedtls_psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_setup( operation, attributes,
key_buffer, key_buffer_size,
alg, MBEDTLS_DECRYPT ) );
}
static psa_status_t cipher_set_iv( mbedtls_psa_cipher_operation_t *operation,
const uint8_t *iv, size_t iv_length )
{
if( iv_length != operation->iv_length )
return( PSA_ERROR_INVALID_ARGUMENT );
return( mbedtls_to_psa_error(
mbedtls_cipher_set_iv( &operation->ctx.cipher,
iv, iv_length ) ) );
}
/** Process input for which the algorithm is set to ECB mode.
*
* This requires manual processing, since the PSA API is defined as being
* able to process arbitrary-length calls to psa_cipher_update() with ECB mode,
* but the underlying mbedtls_cipher_update only takes full blocks.
*
* \param ctx The mbedtls cipher context to use. It must have been
* set up for ECB.
* \param[in] input The input plaintext or ciphertext to process.
* \param input_length The number of bytes to process from \p input.
* This does not need to be aligned to a block boundary.
* If there is a partial block at the end of the input,
* it is stored in \p ctx for future processing.
* \param output The buffer where the output is written. It must be
* at least `BS * floor((p + input_length) / BS)` bytes
* long, where `p` is the number of bytes in the
* unprocessed partial block in \p ctx (with
* `0 <= p <= BS - 1`) and `BS` is the block size.
* \param output_length On success, the number of bytes written to \p output.
* \c 0 on error.
*
* \return #PSA_SUCCESS or an error from a hardware accelerator
*/
static psa_status_t psa_cipher_update_ecb(
mbedtls_cipher_context_t *ctx,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t block_size = ctx->cipher_info->block_size;
size_t internal_output_length = 0;
*output_length = 0;
if( input_length == 0 )
{
status = PSA_SUCCESS;
goto exit;
}
if( ctx->unprocessed_len > 0 )
{
/* Fill up to block size, and run the block if there's a full one. */
size_t bytes_to_copy = block_size - ctx->unprocessed_len;
if( input_length < bytes_to_copy )
bytes_to_copy = input_length;
memcpy( &( ctx->unprocessed_data[ctx->unprocessed_len] ),
input, bytes_to_copy );
input_length -= bytes_to_copy;
input += bytes_to_copy;
ctx->unprocessed_len += bytes_to_copy;
if( ctx->unprocessed_len == block_size )
{
status = mbedtls_to_psa_error(
mbedtls_cipher_update( ctx,
ctx->unprocessed_data,
block_size,
output, &internal_output_length ) );
if( status != PSA_SUCCESS )
goto exit;
output += internal_output_length;
*output_length += internal_output_length;
ctx->unprocessed_len = 0;
}
}
while( input_length >= block_size )
{
/* Run all full blocks we have, one by one */
status = mbedtls_to_psa_error(
mbedtls_cipher_update( ctx, input,
block_size,
output, &internal_output_length ) );
if( status != PSA_SUCCESS )
goto exit;
input_length -= block_size;
input += block_size;
output += internal_output_length;
*output_length += internal_output_length;
}
if( input_length > 0 )
{
/* Save unprocessed bytes for later processing */
memcpy( &( ctx->unprocessed_data[ctx->unprocessed_len] ),
input, input_length );
ctx->unprocessed_len += input_length;
}
status = PSA_SUCCESS;
exit:
return( status );
}
static psa_status_t cipher_update( mbedtls_psa_cipher_operation_t *operation,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t expected_output_size;
if( ! PSA_ALG_IS_STREAM_CIPHER( operation->alg ) )
{
/* Take the unprocessed partial block left over from previous
* update calls, if any, plus the input to this call. Remove
* the last partial block, if any. You get the data that will be
* output in this call. */
expected_output_size =
( operation->ctx.cipher.unprocessed_len + input_length )
/ operation->block_length * operation->block_length;
}
else
{
expected_output_size = input_length;
}
if( output_size < expected_output_size )
return( PSA_ERROR_BUFFER_TOO_SMALL );
if( operation->alg == PSA_ALG_ECB_NO_PADDING )
{
/* mbedtls_cipher_update has an API inconsistency: it will only
* process a single block at a time in ECB mode. Abstract away that
* inconsistency here to match the PSA API behaviour. */
status = psa_cipher_update_ecb( &operation->ctx.cipher,
input,
input_length,
output,
output_length );
}
else
{
status = mbedtls_to_psa_error(
mbedtls_cipher_update( &operation->ctx.cipher, input,
input_length, output, output_length ) );
if( *output_length > output_size )
return( PSA_ERROR_CORRUPTION_DETECTED );
}
return( status );
}
static psa_status_t cipher_finish( mbedtls_psa_cipher_operation_t *operation,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_GENERIC_ERROR;
uint8_t temp_output_buffer[MBEDTLS_MAX_BLOCK_LENGTH];
if( operation->ctx.cipher.unprocessed_len != 0 )
{
if( operation->alg == PSA_ALG_ECB_NO_PADDING ||
operation->alg == PSA_ALG_CBC_NO_PADDING )
{
status = PSA_ERROR_INVALID_ARGUMENT;
goto exit;
}
}
status = mbedtls_to_psa_error(
mbedtls_cipher_finish( &operation->ctx.cipher,
temp_output_buffer,
output_length ) );
if( status != PSA_SUCCESS )
goto exit;
if( *output_length == 0 )
; /* Nothing to copy. Note that output may be NULL in this case. */
else if( output_size >= *output_length )
memcpy( output, temp_output_buffer, *output_length );
else
status = PSA_ERROR_BUFFER_TOO_SMALL;
exit:
mbedtls_platform_zeroize( temp_output_buffer,
sizeof( temp_output_buffer ) );
return( status );
}
static psa_status_t cipher_abort( mbedtls_psa_cipher_operation_t *operation )
{
/* Sanity check (shouldn't happen: operation->alg should
* always have been initialized to a valid value). */
if( ! PSA_ALG_IS_CIPHER( operation->alg ) )
return( PSA_ERROR_BAD_STATE );
mbedtls_cipher_free( &operation->ctx.cipher );
return( PSA_SUCCESS );
}
static psa_status_t cipher_encrypt( const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_psa_cipher_operation_t operation = MBEDTLS_PSA_CIPHER_OPERATION_INIT;
size_t olength, accumulated_length;
status = cipher_encrypt_setup( &operation, attributes,
key_buffer, key_buffer_size, alg );
if( status != PSA_SUCCESS )
goto exit;
accumulated_length = 0;
if( operation.iv_length > 0 )
{
status = cipher_set_iv( &operation, output, operation.iv_length );
if( status != PSA_SUCCESS )
goto exit;
accumulated_length = operation.iv_length;
}
status = cipher_update( &operation, input, input_length,
output + operation.iv_length,
output_size - operation.iv_length,
&olength );
if( status != PSA_SUCCESS )
goto exit;
accumulated_length += olength;
status = cipher_finish( &operation, output + accumulated_length,
output_size - accumulated_length, &olength );
if( status != PSA_SUCCESS )
goto exit;
*output_length = accumulated_length + olength;
exit:
if( status == PSA_SUCCESS )
status = cipher_abort( &operation );
else
cipher_abort( &operation );
return( status );
}
static psa_status_t cipher_decrypt( const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_psa_cipher_operation_t operation = MBEDTLS_PSA_CIPHER_OPERATION_INIT;
size_t olength, accumulated_length;
status = cipher_decrypt_setup( &operation, attributes,
key_buffer, key_buffer_size, alg );
if( status != PSA_SUCCESS )
goto exit;
if( operation.iv_length > 0 )
{
status = cipher_set_iv( &operation, input, operation.iv_length );
if( status != PSA_SUCCESS )
goto exit;
}
status = cipher_update( &operation, input + operation.iv_length,
input_length - operation.iv_length,
output, output_size, &olength );
if( status != PSA_SUCCESS )
goto exit;
accumulated_length = olength;
status = cipher_finish( &operation, output + accumulated_length,
output_size - accumulated_length, &olength );
if( status != PSA_SUCCESS )
goto exit;
*output_length = accumulated_length + olength;
exit:
if ( status == PSA_SUCCESS )
status = cipher_abort( &operation );
else
cipher_abort( &operation );
return( status );
}
#endif /* MBEDTLS_PSA_BUILTIN_CIPHER || PSA_CRYPTO_DRIVER_TEST */
#if defined(MBEDTLS_PSA_BUILTIN_CIPHER)
psa_status_t mbedtls_psa_cipher_encrypt_setup(
mbedtls_psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_encrypt_setup(
operation, attributes, key_buffer, key_buffer_size, alg ) );
}
psa_status_t mbedtls_psa_cipher_decrypt_setup(
mbedtls_psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_decrypt_setup(
operation, attributes, key_buffer, key_buffer_size, alg ) );
}
psa_status_t mbedtls_psa_cipher_set_iv( mbedtls_psa_cipher_operation_t *operation,
const uint8_t *iv,
size_t iv_length )
{
return( cipher_set_iv( operation, iv, iv_length ) );
}
psa_status_t mbedtls_psa_cipher_update( mbedtls_psa_cipher_operation_t *operation,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
return( cipher_update( operation, input, input_length,
output, output_size, output_length ) );
}
psa_status_t mbedtls_psa_cipher_finish( mbedtls_psa_cipher_operation_t *operation,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
return( cipher_finish( operation, output, output_size, output_length ) );
}
psa_status_t mbedtls_psa_cipher_abort( mbedtls_psa_cipher_operation_t *operation )
{
return( cipher_abort( operation ) );
}
psa_status_t mbedtls_psa_cipher_encrypt( const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
return( cipher_encrypt( attributes, key_buffer, key_buffer_size,
alg, input, input_length,
output, output_size, output_length ) );
}
psa_status_t mbedtls_psa_cipher_decrypt( const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
return( cipher_decrypt( attributes, key_buffer, key_buffer_size,
alg, input, input_length,
output, output_size, output_length ) );
}
#endif /* MBEDTLS_PSA_BUILTIN_CIPHER */
/*
* BEYOND THIS POINT, TEST DRIVER ENTRY POINTS ONLY.
*/
#if defined(PSA_CRYPTO_DRIVER_TEST)
psa_status_t mbedtls_transparent_test_driver_cipher_encrypt_setup(
mbedtls_psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_encrypt_setup(
operation, attributes, key_buffer, key_buffer_size, alg ) );
}
psa_status_t mbedtls_transparent_test_driver_cipher_decrypt_setup(
mbedtls_psa_cipher_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg )
{
return( cipher_decrypt_setup(
operation, attributes, key_buffer, key_buffer_size, alg ) );
}
psa_status_t mbedtls_transparent_test_driver_cipher_set_iv(
mbedtls_psa_cipher_operation_t *operation,
const uint8_t *iv, size_t iv_length )
{
return( cipher_set_iv( operation, iv, iv_length ) );
}
psa_status_t mbedtls_transparent_test_driver_cipher_update(
mbedtls_psa_cipher_operation_t *operation,
const uint8_t *input, size_t input_length,
uint8_t *output, size_t output_size, size_t *output_length )
{
return( cipher_update( operation, input, input_length,
output, output_size, output_length ) );
}
psa_status_t mbedtls_transparent_test_driver_cipher_finish(
mbedtls_psa_cipher_operation_t *operation,
uint8_t *output, size_t output_size, size_t *output_length )
{
return( cipher_finish( operation, output, output_size, output_length ) );
}
psa_status_t mbedtls_transparent_test_driver_cipher_abort(
mbedtls_psa_cipher_operation_t *operation )
{
return( cipher_abort( operation ) );
}
psa_status_t mbedtls_transparent_test_driver_cipher_encrypt(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
return( cipher_encrypt( attributes, key_buffer, key_buffer_size,
alg, input, input_length,
output, output_size, output_length ) );
}
psa_status_t mbedtls_transparent_test_driver_cipher_decrypt(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length )
{
return( cipher_decrypt( attributes, key_buffer, key_buffer_size,
alg, input, input_length,
output, output_size, output_length ) );
}
#endif /* PSA_CRYPTO_DRIVER_TEST */
#endif /* MBEDTLS_PSA_CRYPTO_C */
Reference in a new issue View git blame Copy permalink