xref: /aosp_15_r20/external/boringssl/src/decrepit/cfb/cfb.c (revision 8fb009dc861624b67b6cdb62ea21f0f22d0c584b)
1 // Copyright (c) 2017, Google Inc.
2 //
3 // Permission to use, copy, modify, and/or distribute this software for any
4 // purpose with or without fee is hereby granted, provided that the above
5 // copyright notice and this permission notice appear in all copies.
6 //
7 // THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
8 // WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
9 // MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY
10 // SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
11 // WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN ACTION
12 // OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF OR IN
13 // CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
14 
15 #include <openssl/cipher.h>
16 
17 #include <string.h>
18 
19 #include <openssl/aes.h>
20 #include <openssl/obj.h>
21 
22 #include "../../crypto/fipsmodule/cipher/internal.h"
23 #include "../../crypto/internal.h"
24 
25 typedef struct {
26   AES_KEY ks;
27 } EVP_CFB_CTX;
28 
aes_cfb_init_key(EVP_CIPHER_CTX * ctx,const uint8_t * key,const uint8_t * iv,int enc)29 static int aes_cfb_init_key(EVP_CIPHER_CTX *ctx, const uint8_t *key,
30                             const uint8_t *iv, int enc) {
31   if (key) {
32     EVP_CFB_CTX *cfb_ctx = ctx->cipher_data;
33     AES_set_encrypt_key(key, ctx->key_len * 8, &cfb_ctx->ks);
34   }
35 
36   return 1;
37 }
38 
aes_cfb128_cipher(EVP_CIPHER_CTX * ctx,uint8_t * out,const uint8_t * in,size_t len)39 static int aes_cfb128_cipher(EVP_CIPHER_CTX *ctx, uint8_t *out,
40                              const uint8_t *in, size_t len) {
41   if (!out || !in) {
42     return 0;
43   }
44 
45   EVP_CFB_CTX *cfb_ctx = ctx->cipher_data;
46   int num = ctx->num;
47   AES_cfb128_encrypt(in, out, len, &cfb_ctx->ks, ctx->iv, &num,
48                      ctx->encrypt ? AES_ENCRYPT : AES_DECRYPT);
49   ctx->num = num;
50 
51   return 1;
52 }
53 
54 static const EVP_CIPHER aes_128_cfb128 = {
55     .nid = NID_aes_128_cfb128,
56     .block_size = 1,
57     .key_len = 16,
58     .iv_len = 16,
59     .ctx_size = sizeof(EVP_CFB_CTX),
60     .flags = EVP_CIPH_CFB_MODE,
61     .init = aes_cfb_init_key,
62     .cipher = aes_cfb128_cipher,
63 };
64 
65 static const EVP_CIPHER aes_192_cfb128 = {
66     .nid = NID_aes_192_cfb128,
67     .block_size = 1,
68     .key_len = 24,
69     .iv_len = 16,
70     .ctx_size = sizeof(EVP_CFB_CTX),
71     .flags = EVP_CIPH_CFB_MODE,
72     .init = aes_cfb_init_key,
73     .cipher = aes_cfb128_cipher,
74 };
75 
76 static const EVP_CIPHER aes_256_cfb128 = {
77     .nid = NID_aes_256_cfb128,
78     .block_size = 1,
79     .key_len = 32,
80     .iv_len = 16,
81     .ctx_size = sizeof(EVP_CFB_CTX),
82     .flags = EVP_CIPH_CFB_MODE,
83     .init = aes_cfb_init_key,
84     .cipher = aes_cfb128_cipher,
85 };
86 
EVP_aes_128_cfb128(void)87 const EVP_CIPHER *EVP_aes_128_cfb128(void) { return &aes_128_cfb128; }
EVP_aes_128_cfb(void)88 const EVP_CIPHER *EVP_aes_128_cfb(void) { return &aes_128_cfb128; }
EVP_aes_192_cfb128(void)89 const EVP_CIPHER *EVP_aes_192_cfb128(void) { return &aes_192_cfb128; }
EVP_aes_192_cfb(void)90 const EVP_CIPHER *EVP_aes_192_cfb(void) { return &aes_192_cfb128; }
EVP_aes_256_cfb128(void)91 const EVP_CIPHER *EVP_aes_256_cfb128(void) { return &aes_256_cfb128; }
EVP_aes_256_cfb(void)92 const EVP_CIPHER *EVP_aes_256_cfb(void) { return &aes_256_cfb128; }
93