mbedtls/library/psa_crypto_aead.c
Dave Rodgman e3c05853d6 Header updates
Signed-off-by: Dave Rodgman <dave.rodgman@arm.com>
2023-11-03 12:21:36 +00:00

653 lines
22 KiB
C

/*
* PSA AEAD entry points
*/
/*
* Copyright The Mbed TLS Contributors
* SPDX-License-Identifier: Apache-2.0 OR GPL-2.0-or-later
*/
#include "common.h"
#if defined(MBEDTLS_PSA_CRYPTO_C)
#include "psa_crypto_aead.h"
#include "psa_crypto_core.h"
#include "psa_crypto_cipher.h"
#include <string.h>
#include "mbedtls/platform.h"
#include "mbedtls/ccm.h"
#include "mbedtls/chachapoly.h"
#include "mbedtls/cipher.h"
#include "mbedtls/gcm.h"
#include "mbedtls/error.h"
static psa_status_t psa_aead_setup(
mbedtls_psa_aead_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t key_bits;
const mbedtls_cipher_info_t *cipher_info;
mbedtls_cipher_id_t cipher_id;
(void) key_buffer_size;
key_bits = attributes->core.bits;
cipher_info = mbedtls_cipher_info_from_psa(alg,
attributes->core.type, key_bits,
&cipher_id);
if (cipher_info == NULL) {
return PSA_ERROR_NOT_SUPPORTED;
}
switch (PSA_ALG_AEAD_WITH_SHORTENED_TAG(alg, 0)) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
case PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_CCM, 0):
operation->alg = PSA_ALG_CCM;
/* CCM allows the following tag lengths: 4, 6, 8, 10, 12, 14, 16.
* The call to mbedtls_ccm_encrypt_and_tag or
* mbedtls_ccm_auth_decrypt will validate the tag length. */
if (PSA_BLOCK_CIPHER_BLOCK_LENGTH(attributes->core.type) != 16) {
return PSA_ERROR_INVALID_ARGUMENT;
}
mbedtls_ccm_init(&operation->ctx.ccm);
status = mbedtls_to_psa_error(
mbedtls_ccm_setkey(&operation->ctx.ccm, cipher_id,
key_buffer, (unsigned int) key_bits));
if (status != PSA_SUCCESS) {
return status;
}
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
case PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_GCM, 0):
operation->alg = PSA_ALG_GCM;
/* GCM allows the following tag lengths: 4, 8, 12, 13, 14, 15, 16.
* The call to mbedtls_gcm_crypt_and_tag or
* mbedtls_gcm_auth_decrypt will validate the tag length. */
if (PSA_BLOCK_CIPHER_BLOCK_LENGTH(attributes->core.type) != 16) {
return PSA_ERROR_INVALID_ARGUMENT;
}
mbedtls_gcm_init(&operation->ctx.gcm);
status = mbedtls_to_psa_error(
mbedtls_gcm_setkey(&operation->ctx.gcm, cipher_id,
key_buffer, (unsigned int) key_bits));
if (status != PSA_SUCCESS) {
return status;
}
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
case PSA_ALG_AEAD_WITH_SHORTENED_TAG(PSA_ALG_CHACHA20_POLY1305, 0):
operation->alg = PSA_ALG_CHACHA20_POLY1305;
/* We only support the default tag length. */
if (alg != PSA_ALG_CHACHA20_POLY1305) {
return PSA_ERROR_NOT_SUPPORTED;
}
mbedtls_chachapoly_init(&operation->ctx.chachapoly);
status = mbedtls_to_psa_error(
mbedtls_chachapoly_setkey(&operation->ctx.chachapoly,
key_buffer));
if (status != PSA_SUCCESS) {
return status;
}
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
default:
(void) status;
(void) key_buffer;
return PSA_ERROR_NOT_SUPPORTED;
}
operation->key_type = psa_get_key_type(attributes);
operation->tag_length = PSA_ALG_AEAD_GET_TAG_LENGTH(alg);
return PSA_SUCCESS;
}
psa_status_t mbedtls_psa_aead_encrypt(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *nonce, size_t nonce_length,
const uint8_t *additional_data, size_t additional_data_length,
const uint8_t *plaintext, size_t plaintext_length,
uint8_t *ciphertext, size_t ciphertext_size, size_t *ciphertext_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_psa_aead_operation_t operation = MBEDTLS_PSA_AEAD_OPERATION_INIT;
uint8_t *tag;
status = psa_aead_setup(&operation, attributes, key_buffer,
key_buffer_size, alg);
if (status != PSA_SUCCESS) {
goto exit;
}
/* For all currently supported modes, the tag is at the end of the
* ciphertext. */
if (ciphertext_size < (plaintext_length + operation.tag_length)) {
status = PSA_ERROR_BUFFER_TOO_SMALL;
goto exit;
}
tag = ciphertext + plaintext_length;
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if (operation.alg == PSA_ALG_CCM) {
status = mbedtls_to_psa_error(
mbedtls_ccm_encrypt_and_tag(&operation.ctx.ccm,
plaintext_length,
nonce, nonce_length,
additional_data,
additional_data_length,
plaintext, ciphertext,
tag, operation.tag_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
if (operation.alg == PSA_ALG_GCM) {
status = mbedtls_to_psa_error(
mbedtls_gcm_crypt_and_tag(&operation.ctx.gcm,
MBEDTLS_GCM_ENCRYPT,
plaintext_length,
nonce, nonce_length,
additional_data, additional_data_length,
plaintext, ciphertext,
operation.tag_length, tag));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if (operation.alg == PSA_ALG_CHACHA20_POLY1305) {
if (operation.tag_length != 16) {
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
status = mbedtls_to_psa_error(
mbedtls_chachapoly_encrypt_and_tag(&operation.ctx.chachapoly,
plaintext_length,
nonce,
additional_data,
additional_data_length,
plaintext,
ciphertext,
tag));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
{
(void) tag;
(void) nonce;
(void) nonce_length;
(void) additional_data;
(void) additional_data_length;
(void) plaintext;
return PSA_ERROR_NOT_SUPPORTED;
}
if (status == PSA_SUCCESS) {
*ciphertext_length = plaintext_length + operation.tag_length;
}
exit:
mbedtls_psa_aead_abort(&operation);
return status;
}
/* Locate the tag in a ciphertext buffer containing the encrypted data
* followed by the tag. Return the length of the part preceding the tag in
* *plaintext_length. This is the size of the plaintext in modes where
* the encrypted data has the same size as the plaintext, such as
* CCM and GCM. */
static psa_status_t psa_aead_unpadded_locate_tag(size_t tag_length,
const uint8_t *ciphertext,
size_t ciphertext_length,
size_t plaintext_size,
const uint8_t **p_tag)
{
size_t payload_length;
if (tag_length > ciphertext_length) {
return PSA_ERROR_INVALID_ARGUMENT;
}
payload_length = ciphertext_length - tag_length;
if (payload_length > plaintext_size) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
*p_tag = ciphertext + payload_length;
return PSA_SUCCESS;
}
psa_status_t mbedtls_psa_aead_decrypt(
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer, size_t key_buffer_size,
psa_algorithm_t alg,
const uint8_t *nonce, size_t nonce_length,
const uint8_t *additional_data, size_t additional_data_length,
const uint8_t *ciphertext, size_t ciphertext_length,
uint8_t *plaintext, size_t plaintext_size, size_t *plaintext_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
mbedtls_psa_aead_operation_t operation = MBEDTLS_PSA_AEAD_OPERATION_INIT;
const uint8_t *tag = NULL;
status = psa_aead_setup(&operation, attributes, key_buffer,
key_buffer_size, alg);
if (status != PSA_SUCCESS) {
goto exit;
}
status = psa_aead_unpadded_locate_tag(operation.tag_length,
ciphertext, ciphertext_length,
plaintext_size, &tag);
if (status != PSA_SUCCESS) {
goto exit;
}
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if (operation.alg == PSA_ALG_CCM) {
status = mbedtls_to_psa_error(
mbedtls_ccm_auth_decrypt(&operation.ctx.ccm,
ciphertext_length - operation.tag_length,
nonce, nonce_length,
additional_data,
additional_data_length,
ciphertext, plaintext,
tag, operation.tag_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
if (operation.alg == PSA_ALG_GCM) {
status = mbedtls_to_psa_error(
mbedtls_gcm_auth_decrypt(&operation.ctx.gcm,
ciphertext_length - operation.tag_length,
nonce, nonce_length,
additional_data,
additional_data_length,
tag, operation.tag_length,
ciphertext, plaintext));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if (operation.alg == PSA_ALG_CHACHA20_POLY1305) {
if (operation.tag_length != 16) {
status = PSA_ERROR_NOT_SUPPORTED;
goto exit;
}
status = mbedtls_to_psa_error(
mbedtls_chachapoly_auth_decrypt(&operation.ctx.chachapoly,
ciphertext_length - operation.tag_length,
nonce,
additional_data,
additional_data_length,
tag,
ciphertext,
plaintext));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
{
(void) nonce;
(void) nonce_length;
(void) additional_data;
(void) additional_data_length;
(void) plaintext;
return PSA_ERROR_NOT_SUPPORTED;
}
if (status == PSA_SUCCESS) {
*plaintext_length = ciphertext_length - operation.tag_length;
}
exit:
mbedtls_psa_aead_abort(&operation);
if (status == PSA_SUCCESS) {
*plaintext_length = ciphertext_length - operation.tag_length;
}
return status;
}
/* Set the key and algorithm for a multipart authenticated encryption
* operation. */
psa_status_t mbedtls_psa_aead_encrypt_setup(
mbedtls_psa_aead_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
status = psa_aead_setup(operation, attributes, key_buffer,
key_buffer_size, alg);
if (status == PSA_SUCCESS) {
operation->is_encrypt = 1;
}
return status;
}
/* Set the key and algorithm for a multipart authenticated decryption
* operation. */
psa_status_t mbedtls_psa_aead_decrypt_setup(
mbedtls_psa_aead_operation_t *operation,
const psa_key_attributes_t *attributes,
const uint8_t *key_buffer,
size_t key_buffer_size,
psa_algorithm_t alg)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
status = psa_aead_setup(operation, attributes, key_buffer,
key_buffer_size, alg);
if (status == PSA_SUCCESS) {
operation->is_encrypt = 0;
}
return status;
}
/* Set a nonce for the multipart AEAD operation*/
psa_status_t mbedtls_psa_aead_set_nonce(
mbedtls_psa_aead_operation_t *operation,
const uint8_t *nonce,
size_t nonce_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
if (operation->alg == PSA_ALG_GCM) {
status = mbedtls_to_psa_error(
mbedtls_gcm_starts(&operation->ctx.gcm,
operation->is_encrypt ?
MBEDTLS_GCM_ENCRYPT : MBEDTLS_GCM_DECRYPT,
nonce,
nonce_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if (operation->alg == PSA_ALG_CCM) {
status = mbedtls_to_psa_error(
mbedtls_ccm_starts(&operation->ctx.ccm,
operation->is_encrypt ?
MBEDTLS_CCM_ENCRYPT : MBEDTLS_CCM_DECRYPT,
nonce,
nonce_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if (operation->alg == PSA_ALG_CHACHA20_POLY1305) {
/* Note - ChaChaPoly allows an 8 byte nonce, but we would have to
* allocate a buffer in the operation, copy the nonce to it and pad
* it, so for now check the nonce is 12 bytes, as
* mbedtls_chachapoly_starts() assumes it can read 12 bytes from the
* passed in buffer. */
if (nonce_length != 12) {
return PSA_ERROR_INVALID_ARGUMENT;
}
status = mbedtls_to_psa_error(
mbedtls_chachapoly_starts(&operation->ctx.chachapoly,
nonce,
operation->is_encrypt ?
MBEDTLS_CHACHAPOLY_ENCRYPT :
MBEDTLS_CHACHAPOLY_DECRYPT));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
{
(void) operation;
(void) nonce;
(void) nonce_length;
return PSA_ERROR_NOT_SUPPORTED;
}
return status;
}
/* Declare the lengths of the message and additional data for AEAD. */
psa_status_t mbedtls_psa_aead_set_lengths(
mbedtls_psa_aead_operation_t *operation,
size_t ad_length,
size_t plaintext_length)
{
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if (operation->alg == PSA_ALG_CCM) {
return mbedtls_to_psa_error(
mbedtls_ccm_set_lengths(&operation->ctx.ccm,
ad_length,
plaintext_length,
operation->tag_length));
}
#else /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
(void) operation;
(void) ad_length;
(void) plaintext_length;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
return PSA_SUCCESS;
}
/* Pass additional data to an active multipart AEAD operation. */
psa_status_t mbedtls_psa_aead_update_ad(
mbedtls_psa_aead_operation_t *operation,
const uint8_t *input,
size_t input_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
if (operation->alg == PSA_ALG_GCM) {
status = mbedtls_to_psa_error(
mbedtls_gcm_update_ad(&operation->ctx.gcm, input, input_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if (operation->alg == PSA_ALG_CCM) {
status = mbedtls_to_psa_error(
mbedtls_ccm_update_ad(&operation->ctx.ccm, input, input_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if (operation->alg == PSA_ALG_CHACHA20_POLY1305) {
status = mbedtls_to_psa_error(
mbedtls_chachapoly_update_aad(&operation->ctx.chachapoly,
input,
input_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
{
(void) operation;
(void) input;
(void) input_length;
return PSA_ERROR_NOT_SUPPORTED;
}
return status;
}
/* Encrypt or decrypt a message fragment in an active multipart AEAD
* operation.*/
psa_status_t mbedtls_psa_aead_update(
mbedtls_psa_aead_operation_t *operation,
const uint8_t *input,
size_t input_length,
uint8_t *output,
size_t output_size,
size_t *output_length)
{
size_t update_output_length;
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
update_output_length = input_length;
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
if (operation->alg == PSA_ALG_GCM) {
status = mbedtls_to_psa_error(
mbedtls_gcm_update(&operation->ctx.gcm,
input, input_length,
output, output_size,
&update_output_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if (operation->alg == PSA_ALG_CCM) {
if (output_size < input_length) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
status = mbedtls_to_psa_error(
mbedtls_ccm_update(&operation->ctx.ccm,
input, input_length,
output, output_size,
&update_output_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if (operation->alg == PSA_ALG_CHACHA20_POLY1305) {
if (output_size < input_length) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
status = mbedtls_to_psa_error(
mbedtls_chachapoly_update(&operation->ctx.chachapoly,
input_length,
input,
output));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
{
(void) operation;
(void) input;
(void) output;
(void) output_size;
return PSA_ERROR_NOT_SUPPORTED;
}
if (status == PSA_SUCCESS) {
*output_length = update_output_length;
}
return status;
}
/* Finish encrypting a message in a multipart AEAD operation. */
psa_status_t mbedtls_psa_aead_finish(
mbedtls_psa_aead_operation_t *operation,
uint8_t *ciphertext,
size_t ciphertext_size,
size_t *ciphertext_length,
uint8_t *tag,
size_t tag_size,
size_t *tag_length)
{
psa_status_t status = PSA_ERROR_CORRUPTION_DETECTED;
size_t finish_output_size = 0;
if (tag_size < operation->tag_length) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
if (operation->alg == PSA_ALG_GCM) {
status = mbedtls_to_psa_error(
mbedtls_gcm_finish(&operation->ctx.gcm,
ciphertext, ciphertext_size, ciphertext_length,
tag, operation->tag_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
if (operation->alg == PSA_ALG_CCM) {
/* tag must be big enough to store a tag of size passed into set
* lengths. */
if (tag_size < operation->tag_length) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
status = mbedtls_to_psa_error(
mbedtls_ccm_finish(&operation->ctx.ccm,
tag, operation->tag_length));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
if (operation->alg == PSA_ALG_CHACHA20_POLY1305) {
/* Belt and braces. Although the above tag_size check should have
* already done this, if we later start supporting smaller tag sizes
* for chachapoly, then passing a tag buffer smaller than 16 into here
* could cause a buffer overflow, so better safe than sorry. */
if (tag_size < 16) {
return PSA_ERROR_BUFFER_TOO_SMALL;
}
status = mbedtls_to_psa_error(
mbedtls_chachapoly_finish(&operation->ctx.chachapoly,
tag));
} else
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
{
(void) ciphertext;
(void) ciphertext_size;
(void) ciphertext_length;
(void) tag;
(void) tag_size;
(void) tag_length;
return PSA_ERROR_NOT_SUPPORTED;
}
if (status == PSA_SUCCESS) {
/* This will be zero for all supported algorithms currently, but left
* here for future support. */
*ciphertext_length = finish_output_size;
*tag_length = operation->tag_length;
}
return status;
}
/* Abort an AEAD operation */
psa_status_t mbedtls_psa_aead_abort(
mbedtls_psa_aead_operation_t *operation)
{
switch (operation->alg) {
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CCM)
case PSA_ALG_CCM:
mbedtls_ccm_free(&operation->ctx.ccm);
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_GCM)
case PSA_ALG_GCM:
mbedtls_gcm_free(&operation->ctx.gcm);
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_GCM */
#if defined(MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305)
case PSA_ALG_CHACHA20_POLY1305:
mbedtls_chachapoly_free(&operation->ctx.chachapoly);
break;
#endif /* MBEDTLS_PSA_BUILTIN_ALG_CHACHA20_POLY1305 */
}
operation->is_encrypt = 0;
return PSA_SUCCESS;
}
#endif /* MBEDTLS_PSA_CRYPTO_C */