1 /*
2 * Copyright 2019-2023 The OpenSSL Project Authors. All Rights Reserved.
3 *
4 * Licensed under the Apache License 2.0 (the "License"). You may not use
5 * this file except in compliance with the License. You can obtain a copy
6 * in the file LICENSE in the source distribution or at
7 * https://www.openssl.org/source/license.html
8 */
9
10 /*
11 * This file uses the low level AES functions (which are deprecated for
12 * non-internal use) in order to implement provider AES ciphers.
13 */
14 #include "internal/deprecated.h"
15
16 #include <openssl/proverr.h>
17 #include "cipher_aes.h"
18 #include "prov/providercommon.h"
19 #include "prov/implementations.h"
20
21 /* AES wrap with padding has IV length of 4, without padding 8 */
22 #define AES_WRAP_PAD_IVLEN 4
23 #define AES_WRAP_NOPAD_IVLEN 8
24
25 #define WRAP_FLAGS (PROV_CIPHER_FLAG_CUSTOM_IV)
26 #define WRAP_FLAGS_INV (WRAP_FLAGS | PROV_CIPHER_FLAG_INVERSE_CIPHER)
27
28 typedef size_t (*aeswrap_fn)(void *key, const unsigned char *iv,
29 unsigned char *out, const unsigned char *in,
30 size_t inlen, block128_f block);
31
32 static OSSL_FUNC_cipher_encrypt_init_fn aes_wrap_einit;
33 static OSSL_FUNC_cipher_decrypt_init_fn aes_wrap_dinit;
34 static OSSL_FUNC_cipher_update_fn aes_wrap_cipher;
35 static OSSL_FUNC_cipher_final_fn aes_wrap_final;
36 static OSSL_FUNC_cipher_freectx_fn aes_wrap_freectx;
37 static OSSL_FUNC_cipher_set_ctx_params_fn aes_wrap_set_ctx_params;
38
39 typedef struct prov_aes_wrap_ctx_st {
40 PROV_CIPHER_CTX base;
41 union {
42 OSSL_UNION_ALIGN;
43 AES_KEY ks;
44 } ks;
45 aeswrap_fn wrapfn;
46
47 } PROV_AES_WRAP_CTX;
48
49
aes_wrap_newctx(size_t kbits,size_t blkbits,size_t ivbits,unsigned int mode,uint64_t flags)50 static void *aes_wrap_newctx(size_t kbits, size_t blkbits,
51 size_t ivbits, unsigned int mode, uint64_t flags)
52 {
53 PROV_AES_WRAP_CTX *wctx;
54 PROV_CIPHER_CTX *ctx;
55
56 if (!ossl_prov_is_running())
57 return NULL;
58
59 wctx = OPENSSL_zalloc(sizeof(*wctx));
60 ctx = (PROV_CIPHER_CTX *)wctx;
61 if (ctx != NULL) {
62 ossl_cipher_generic_initkey(ctx, kbits, blkbits, ivbits, mode, flags,
63 NULL, NULL);
64 ctx->pad = (ctx->ivlen == AES_WRAP_PAD_IVLEN);
65 }
66 return wctx;
67 }
68
aes_wrap_dupctx(void * wctx)69 static void *aes_wrap_dupctx(void *wctx)
70 {
71 PROV_AES_WRAP_CTX *ctx = wctx;
72 PROV_AES_WRAP_CTX *dctx = wctx;
73
74 if (!ossl_prov_is_running())
75 return NULL;
76
77 if (ctx == NULL)
78 return NULL;
79 dctx = OPENSSL_memdup(ctx, sizeof(*ctx));
80
81 if (dctx != NULL && dctx->base.tlsmac != NULL && dctx->base.alloced) {
82 dctx->base.tlsmac = OPENSSL_memdup(dctx->base.tlsmac,
83 dctx->base.tlsmacsize);
84 if (dctx->base.tlsmac == NULL) {
85 OPENSSL_free(dctx);
86 dctx = NULL;
87 }
88 }
89 return dctx;
90 }
91
aes_wrap_freectx(void * vctx)92 static void aes_wrap_freectx(void *vctx)
93 {
94 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
95
96 ossl_cipher_generic_reset_ctx((PROV_CIPHER_CTX *)vctx);
97 OPENSSL_clear_free(wctx, sizeof(*wctx));
98 }
99
aes_wrap_init(void * vctx,const unsigned char * key,size_t keylen,const unsigned char * iv,size_t ivlen,const OSSL_PARAM params[],int enc)100 static int aes_wrap_init(void *vctx, const unsigned char *key,
101 size_t keylen, const unsigned char *iv,
102 size_t ivlen, const OSSL_PARAM params[], int enc)
103 {
104 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
105 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
106
107 if (!ossl_prov_is_running())
108 return 0;
109
110 ctx->enc = enc;
111 if (ctx->pad)
112 wctx->wrapfn = enc ? CRYPTO_128_wrap_pad : CRYPTO_128_unwrap_pad;
113 else
114 wctx->wrapfn = enc ? CRYPTO_128_wrap : CRYPTO_128_unwrap;
115
116 if (iv != NULL) {
117 if (!ossl_cipher_generic_initiv(ctx, iv, ivlen))
118 return 0;
119 }
120 if (key != NULL) {
121 int use_forward_transform;
122
123 if (keylen != ctx->keylen) {
124 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
125 return 0;
126 }
127 /*
128 * See SP800-38F : Section 5.1
129 * The forward and inverse transformations for the AES block
130 * cipher—called “cipher” and “inverse cipher” are informally known as
131 * the AES encryption and AES decryption functions, respectively.
132 * If the designated cipher function for a key-wrap algorithm is chosen
133 * to be the AES decryption function, then CIPH-1K will be the AES
134 * encryption function.
135 */
136 if (ctx->inverse_cipher == 0)
137 use_forward_transform = ctx->enc;
138 else
139 use_forward_transform = !ctx->enc;
140 if (use_forward_transform) {
141 AES_set_encrypt_key(key, keylen * 8, &wctx->ks.ks);
142 ctx->block = (block128_f)AES_encrypt;
143 } else {
144 AES_set_decrypt_key(key, keylen * 8, &wctx->ks.ks);
145 ctx->block = (block128_f)AES_decrypt;
146 }
147 }
148 return aes_wrap_set_ctx_params(ctx, params);
149 }
150
aes_wrap_einit(void * ctx,const unsigned char * key,size_t keylen,const unsigned char * iv,size_t ivlen,const OSSL_PARAM params[])151 static int aes_wrap_einit(void *ctx, const unsigned char *key, size_t keylen,
152 const unsigned char *iv, size_t ivlen,
153 const OSSL_PARAM params[])
154 {
155 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 1);
156 }
157
aes_wrap_dinit(void * ctx,const unsigned char * key,size_t keylen,const unsigned char * iv,size_t ivlen,const OSSL_PARAM params[])158 static int aes_wrap_dinit(void *ctx, const unsigned char *key, size_t keylen,
159 const unsigned char *iv, size_t ivlen,
160 const OSSL_PARAM params[])
161 {
162 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 0);
163 }
164
aes_wrap_cipher_internal(void * vctx,unsigned char * out,const unsigned char * in,size_t inlen)165 static int aes_wrap_cipher_internal(void *vctx, unsigned char *out,
166 const unsigned char *in, size_t inlen)
167 {
168 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
169 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
170 size_t rv;
171 int pad = ctx->pad;
172
173 /* No final operation so always return zero length */
174 if (in == NULL)
175 return 0;
176
177 /* Input length must always be non-zero */
178 if (inlen == 0) {
179 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH);
180 return -1;
181 }
182
183 /* If decrypting need at least 16 bytes and multiple of 8 */
184 if (!ctx->enc && (inlen < 16 || inlen & 0x7)) {
185 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH);
186 return -1;
187 }
188
189 /* If not padding input must be multiple of 8 */
190 if (!pad && inlen & 0x7) {
191 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH);
192 return -1;
193 }
194
195 if (out == NULL) {
196 if (ctx->enc) {
197 /* If padding round up to multiple of 8 */
198 if (pad)
199 inlen = (inlen + 7) / 8 * 8;
200 /* 8 byte prefix */
201 return inlen + 8;
202 } else {
203 /*
204 * If not padding output will be exactly 8 bytes smaller than
205 * input. If padding it will be at least 8 bytes smaller but we
206 * don't know how much.
207 */
208 return inlen - 8;
209 }
210 }
211
212 rv = wctx->wrapfn(&wctx->ks.ks, ctx->iv_set ? ctx->iv : NULL, out, in,
213 inlen, ctx->block);
214 if (!rv) {
215 ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED);
216 return -1;
217 }
218 if (rv > INT_MAX) {
219 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_OUTPUT_LENGTH);
220 return -1;
221 }
222 return (int)rv;
223 }
224
aes_wrap_final(void * vctx,unsigned char * out,size_t * outl,size_t outsize)225 static int aes_wrap_final(void *vctx, unsigned char *out, size_t *outl,
226 size_t outsize)
227 {
228 if (!ossl_prov_is_running())
229 return 0;
230
231 *outl = 0;
232 return 1;
233 }
234
aes_wrap_cipher(void * vctx,unsigned char * out,size_t * outl,size_t outsize,const unsigned char * in,size_t inl)235 static int aes_wrap_cipher(void *vctx,
236 unsigned char *out, size_t *outl, size_t outsize,
237 const unsigned char *in, size_t inl)
238 {
239 PROV_AES_WRAP_CTX *ctx = (PROV_AES_WRAP_CTX *)vctx;
240 size_t len;
241
242 if (!ossl_prov_is_running())
243 return 0;
244
245 if (inl == 0) {
246 *outl = 0;
247 return 1;
248 }
249
250 if (outsize < inl) {
251 ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
252 return 0;
253 }
254
255 len = aes_wrap_cipher_internal(ctx, out, in, inl);
256 if (len <= 0)
257 return 0;
258
259 *outl = len;
260 return 1;
261 }
262
aes_wrap_set_ctx_params(void * vctx,const OSSL_PARAM params[])263 static int aes_wrap_set_ctx_params(void *vctx, const OSSL_PARAM params[])
264 {
265 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
266 const OSSL_PARAM *p;
267 size_t keylen = 0;
268
269 if (ossl_param_is_empty(params))
270 return 1;
271
272 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN);
273 if (p != NULL) {
274 if (!OSSL_PARAM_get_size_t(p, &keylen)) {
275 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER);
276 return 0;
277 }
278 if (ctx->keylen != keylen) {
279 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
280 return 0;
281 }
282 }
283 return 1;
284 }
285
286 #define IMPLEMENT_cipher(mode, fname, UCMODE, flags, kbits, blkbits, ivbits) \
287 static OSSL_FUNC_cipher_get_params_fn aes_##kbits##_##fname##_get_params; \
288 static int aes_##kbits##_##fname##_get_params(OSSL_PARAM params[]) \
289 { \
290 return ossl_cipher_generic_get_params(params, EVP_CIPH_##UCMODE##_MODE,\
291 flags, kbits, blkbits, ivbits); \
292 } \
293 static OSSL_FUNC_cipher_newctx_fn aes_##kbits##fname##_newctx; \
294 static void *aes_##kbits##fname##_newctx(void *provctx) \
295 { \
296 return aes_##mode##_newctx(kbits, blkbits, ivbits, \
297 EVP_CIPH_##UCMODE##_MODE, flags); \
298 } \
299 const OSSL_DISPATCH ossl_##aes##kbits##fname##_functions[] = { \
300 { OSSL_FUNC_CIPHER_NEWCTX, \
301 (void (*)(void))aes_##kbits##fname##_newctx }, \
302 { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))aes_##mode##_einit }, \
303 { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))aes_##mode##_dinit }, \
304 { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))aes_##mode##_cipher }, \
305 { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))aes_##mode##_final }, \
306 { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))aes_##mode##_freectx }, \
307 { OSSL_FUNC_CIPHER_DUPCTX, (void (*)(void))aes_##mode##_dupctx }, \
308 { OSSL_FUNC_CIPHER_GET_PARAMS, \
309 (void (*)(void))aes_##kbits##_##fname##_get_params }, \
310 { OSSL_FUNC_CIPHER_GETTABLE_PARAMS, \
311 (void (*)(void))ossl_cipher_generic_gettable_params }, \
312 { OSSL_FUNC_CIPHER_GET_CTX_PARAMS, \
313 (void (*)(void))ossl_cipher_generic_get_ctx_params }, \
314 { OSSL_FUNC_CIPHER_SET_CTX_PARAMS, \
315 (void (*)(void))aes_wrap_set_ctx_params }, \
316 { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS, \
317 (void (*)(void))ossl_cipher_generic_gettable_ctx_params }, \
318 { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS, \
319 (void (*)(void))ossl_cipher_generic_settable_ctx_params }, \
320 OSSL_DISPATCH_END \
321 }
322
323 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_NOPAD_IVLEN * 8);
324 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_NOPAD_IVLEN * 8);
325 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_NOPAD_IVLEN * 8);
326 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_PAD_IVLEN * 8);
327 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_PAD_IVLEN * 8);
328 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_PAD_IVLEN * 8);
329
330 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_NOPAD_IVLEN * 8);
331 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_NOPAD_IVLEN * 8);
332 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_NOPAD_IVLEN * 8);
333 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_PAD_IVLEN * 8);
334 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_PAD_IVLEN * 8);
335 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_PAD_IVLEN * 8);
336
