mbed TLS v2.24.0
gcm.h
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1 
14 /*
15  * Copyright The Mbed TLS Contributors
16  * SPDX-License-Identifier: Apache-2.0
17  *
18  * Licensed under the Apache License, Version 2.0 (the "License"); you may
19  * not use this file except in compliance with the License.
20  * You may obtain a copy of the License at
21  *
22  * http://www.apache.org/licenses/LICENSE-2.0
23  *
24  * Unless required by applicable law or agreed to in writing, software
25  * distributed under the License is distributed on an "AS IS" BASIS, WITHOUT
26  * WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
27  * See the License for the specific language governing permissions and
28  * limitations under the License.
29  */
30 
31 #ifndef MBEDTLS_GCM_H
32 #define MBEDTLS_GCM_H
33 
34 #if !defined(MBEDTLS_CONFIG_FILE)
35 #include "mbedtls/config.h"
36 #else
37 #include MBEDTLS_CONFIG_FILE
38 #endif
39 
40 #include "mbedtls/cipher.h"
41 
42 #include <stdint.h>
43 
44 #define MBEDTLS_GCM_ENCRYPT 1
45 #define MBEDTLS_GCM_DECRYPT 0
46 
47 #define MBEDTLS_ERR_GCM_AUTH_FAILED -0x0012
49 /* MBEDTLS_ERR_GCM_HW_ACCEL_FAILED is deprecated and should not be used. */
50 #define MBEDTLS_ERR_GCM_HW_ACCEL_FAILED -0x0013
52 #define MBEDTLS_ERR_GCM_BAD_INPUT -0x0014
54 #ifdef __cplusplus
55 extern "C" {
56 #endif
57 
58 #if !defined(MBEDTLS_GCM_ALT)
59 
63 typedef struct mbedtls_gcm_context
64 {
65  mbedtls_cipher_context_t cipher_ctx;
66  uint64_t HL[16];
67  uint64_t HH[16];
68  uint64_t len;
69  uint64_t add_len;
70  unsigned char base_ectr[16];
71  unsigned char y[16];
72  unsigned char buf[16];
73  int mode;
76 }
77 mbedtls_gcm_context;
78 
79 #else /* !MBEDTLS_GCM_ALT */
80 #include "gcm_alt.h"
81 #endif /* !MBEDTLS_GCM_ALT */
82 
94 void mbedtls_gcm_init( mbedtls_gcm_context *ctx );
95 
112 int mbedtls_gcm_setkey( mbedtls_gcm_context *ctx,
113  mbedtls_cipher_id_t cipher,
114  const unsigned char *key,
115  unsigned int keybits );
116 
168 int mbedtls_gcm_crypt_and_tag( mbedtls_gcm_context *ctx,
169  int mode,
170  size_t length,
171  const unsigned char *iv,
172  size_t iv_len,
173  const unsigned char *add,
174  size_t add_len,
175  const unsigned char *input,
176  unsigned char *output,
177  size_t tag_len,
178  unsigned char *tag );
179 
213 int mbedtls_gcm_auth_decrypt( mbedtls_gcm_context *ctx,
214  size_t length,
215  const unsigned char *iv,
216  size_t iv_len,
217  const unsigned char *add,
218  size_t add_len,
219  const unsigned char *tag,
220  size_t tag_len,
221  const unsigned char *input,
222  unsigned char *output );
223 
241 int mbedtls_gcm_starts( mbedtls_gcm_context *ctx,
242  int mode,
243  const unsigned char *iv,
244  size_t iv_len,
245  const unsigned char *add,
246  size_t add_len );
247 
273 int mbedtls_gcm_update( mbedtls_gcm_context *ctx,
274  size_t length,
275  const unsigned char *input,
276  unsigned char *output );
277 
294 int mbedtls_gcm_finish( mbedtls_gcm_context *ctx,
295  unsigned char *tag,
296  size_t tag_len );
297 
305 void mbedtls_gcm_free( mbedtls_gcm_context *ctx );
306 
307 #if defined(MBEDTLS_SELF_TEST)
308 
315 int mbedtls_gcm_self_test( int verbose );
316 
317 #endif /* MBEDTLS_SELF_TEST */
318 
319 #ifdef __cplusplus
320 }
321 #endif
322 
323 
324 #endif /* gcm.h */
void mbedtls_gcm_init(mbedtls_gcm_context *ctx)
This function initializes the specified GCM context, to make references valid, and prepares the conte...
int mbedtls_gcm_starts(mbedtls_gcm_context *ctx, int mode, const unsigned char *iv, size_t iv_len, const unsigned char *add, size_t add_len)
This function starts a GCM encryption or decryption operation.
int mbedtls_gcm_self_test(int verbose)
The GCM checkup routine.
void mbedtls_gcm_free(mbedtls_gcm_context *ctx)
This function clears a GCM context and the underlying cipher sub-context.
Configuration options (set of defines)
int mbedtls_gcm_update(mbedtls_gcm_context *ctx, size_t length, const unsigned char *input, unsigned char *output)
This function feeds an input buffer into an ongoing GCM encryption or decryption operation.
mbedtls_cipher_id_t
Supported cipher types.
Definition: cipher.h:82
This file contains an abstraction interface for use with the cipher primitives provided by the librar...
int mbedtls_gcm_setkey(mbedtls_gcm_context *ctx, mbedtls_cipher_id_t cipher, const unsigned char *key, unsigned int keybits)
This function associates a GCM context with a cipher algorithm and a key.
int mbedtls_gcm_finish(mbedtls_gcm_context *ctx, unsigned char *tag, size_t tag_len)
This function finishes the GCM operation and generates the authentication tag.
int mbedtls_gcm_auth_decrypt(mbedtls_gcm_context *ctx, size_t length, const unsigned char *iv, size_t iv_len, const unsigned char *add, size_t add_len, const unsigned char *tag, size_t tag_len, const unsigned char *input, unsigned char *output)
This function performs a GCM authenticated decryption of a buffer.
int mbedtls_gcm_crypt_and_tag(mbedtls_gcm_context *ctx, int mode, size_t length, const unsigned char *iv, size_t iv_len, const unsigned char *add, size_t add_len, const unsigned char *input, unsigned char *output, size_t tag_len, unsigned char *tag)
This function performs GCM encryption or decryption of a buffer.