1 /*
2 * Copyright 2019-2024 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 (ctx == NULL)
75 return NULL;
76 dctx = OPENSSL_memdup(ctx, sizeof(*ctx));
77
78 if (dctx != NULL && dctx->base.tlsmac != NULL && dctx->base.alloced) {
79 dctx->base.tlsmac = OPENSSL_memdup(dctx->base.tlsmac,
80 dctx->base.tlsmacsize);
81 if (dctx->base.tlsmac == NULL) {
82 OPENSSL_free(dctx);
83 dctx = NULL;
84 }
85 }
86 return dctx;
87 }
88
aes_wrap_freectx(void * vctx)89 static void aes_wrap_freectx(void *vctx)
90 {
91 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
92
93 ossl_cipher_generic_reset_ctx((PROV_CIPHER_CTX *)vctx);
94 OPENSSL_clear_free(wctx, sizeof(*wctx));
95 }
96
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)97 static int aes_wrap_init(void *vctx, const unsigned char *key,
98 size_t keylen, const unsigned char *iv,
99 size_t ivlen, const OSSL_PARAM params[], int enc)
100 {
101 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
102 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
103
104 if (!ossl_prov_is_running())
105 return 0;
106
107 ctx->enc = enc;
108 if (ctx->pad)
109 wctx->wrapfn = enc ? CRYPTO_128_wrap_pad : CRYPTO_128_unwrap_pad;
110 else
111 wctx->wrapfn = enc ? CRYPTO_128_wrap : CRYPTO_128_unwrap;
112
113 if (iv != NULL) {
114 if (!ossl_cipher_generic_initiv(ctx, iv, ivlen))
115 return 0;
116 }
117 if (key != NULL) {
118 int use_forward_transform;
119
120 if (keylen != ctx->keylen) {
121 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
122 return 0;
123 }
124 /*
125 * See SP800-38F : Section 5.1
126 * The forward and inverse transformations for the AES block
127 * cipher—called “cipher” and “inverse cipher” are informally known as
128 * the AES encryption and AES decryption functions, respectively.
129 * If the designated cipher function for a key-wrap algorithm is chosen
130 * to be the AES decryption function, then CIPH-1K will be the AES
131 * encryption function.
132 */
133 if (ctx->inverse_cipher == 0)
134 use_forward_transform = ctx->enc;
135 else
136 use_forward_transform = !ctx->enc;
137 if (use_forward_transform) {
138 AES_set_encrypt_key(key, keylen * 8, &wctx->ks.ks);
139 ctx->block = (block128_f)AES_encrypt;
140 } else {
141 AES_set_decrypt_key(key, keylen * 8, &wctx->ks.ks);
142 ctx->block = (block128_f)AES_decrypt;
143 }
144 }
145 return aes_wrap_set_ctx_params(ctx, params);
146 }
147
aes_wrap_einit(void * ctx,const unsigned char * key,size_t keylen,const unsigned char * iv,size_t ivlen,const OSSL_PARAM params[])148 static int aes_wrap_einit(void *ctx, const unsigned char *key, size_t keylen,
149 const unsigned char *iv, size_t ivlen,
150 const OSSL_PARAM params[])
151 {
152 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 1);
153 }
154
aes_wrap_dinit(void * ctx,const unsigned char * key,size_t keylen,const unsigned char * iv,size_t ivlen,const OSSL_PARAM params[])155 static int aes_wrap_dinit(void *ctx, const unsigned char *key, size_t keylen,
156 const unsigned char *iv, size_t ivlen,
157 const OSSL_PARAM params[])
158 {
159 return aes_wrap_init(ctx, key, keylen, iv, ivlen, params, 0);
160 }
161
aes_wrap_cipher_internal(void * vctx,unsigned char * out,const unsigned char * in,size_t inlen)162 static int aes_wrap_cipher_internal(void *vctx, unsigned char *out,
163 const unsigned char *in, size_t inlen)
164 {
165 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
166 PROV_AES_WRAP_CTX *wctx = (PROV_AES_WRAP_CTX *)vctx;
167 size_t rv;
168 int pad = ctx->pad;
169
170 /* No final operation so always return zero length */
171 if (in == NULL)
172 return 0;
173
174 /* Input length must always be non-zero */
175 if (inlen == 0) {
176 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH);
177 return -1;
178 }
179
180 /* If decrypting need at least 16 bytes and multiple of 8 */
181 if (!ctx->enc && (inlen < 16 || inlen & 0x7)) {
182 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH);
183 return -1;
184 }
185
186 /* If not padding input must be multiple of 8 */
187 if (!pad && inlen & 0x7) {
188 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_INPUT_LENGTH);
189 return -1;
190 }
191
192 if (out == NULL) {
193 if (ctx->enc) {
194 /* If padding round up to multiple of 8 */
195 if (pad)
196 inlen = (inlen + 7) / 8 * 8;
197 /* 8 byte prefix */
198 return inlen + 8;
199 } else {
200 /*
201 * If not padding output will be exactly 8 bytes smaller than
202 * input. If padding it will be at least 8 bytes smaller but we
203 * don't know how much.
204 */
205 return inlen - 8;
206 }
207 }
208
209 rv = wctx->wrapfn(&wctx->ks.ks, ctx->iv_set ? ctx->iv : NULL, out, in,
210 inlen, ctx->block);
211 if (!rv) {
212 ERR_raise(ERR_LIB_PROV, PROV_R_CIPHER_OPERATION_FAILED);
213 return -1;
214 }
215 if (rv > INT_MAX) {
216 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_OUTPUT_LENGTH);
217 return -1;
218 }
219 return (int)rv;
220 }
221
aes_wrap_final(void * vctx,unsigned char * out,size_t * outl,size_t outsize)222 static int aes_wrap_final(void *vctx, unsigned char *out, size_t *outl,
223 size_t outsize)
224 {
225 if (!ossl_prov_is_running())
226 return 0;
227
228 *outl = 0;
229 return 1;
230 }
231
aes_wrap_cipher(void * vctx,unsigned char * out,size_t * outl,size_t outsize,const unsigned char * in,size_t inl)232 static int aes_wrap_cipher(void *vctx,
233 unsigned char *out, size_t *outl, size_t outsize,
234 const unsigned char *in, size_t inl)
235 {
236 PROV_AES_WRAP_CTX *ctx = (PROV_AES_WRAP_CTX *)vctx;
237 size_t len;
238
239 if (!ossl_prov_is_running())
240 return 0;
241
242 if (inl == 0) {
243 *outl = 0;
244 return 1;
245 }
246
247 if (outsize < inl) {
248 ERR_raise(ERR_LIB_PROV, PROV_R_OUTPUT_BUFFER_TOO_SMALL);
249 return 0;
250 }
251
252 len = aes_wrap_cipher_internal(ctx, out, in, inl);
253 if (len <= 0)
254 return 0;
255
256 *outl = len;
257 return 1;
258 }
259
aes_wrap_set_ctx_params(void * vctx,const OSSL_PARAM params[])260 static int aes_wrap_set_ctx_params(void *vctx, const OSSL_PARAM params[])
261 {
262 PROV_CIPHER_CTX *ctx = (PROV_CIPHER_CTX *)vctx;
263 const OSSL_PARAM *p;
264 size_t keylen = 0;
265
266 if (params == NULL)
267 return 1;
268
269 p = OSSL_PARAM_locate_const(params, OSSL_CIPHER_PARAM_KEYLEN);
270 if (p != NULL) {
271 if (!OSSL_PARAM_get_size_t(p, &keylen)) {
272 ERR_raise(ERR_LIB_PROV, PROV_R_FAILED_TO_GET_PARAMETER);
273 return 0;
274 }
275 if (ctx->keylen != keylen) {
276 ERR_raise(ERR_LIB_PROV, PROV_R_INVALID_KEY_LENGTH);
277 return 0;
278 }
279 }
280 return 1;
281 }
282
283 #define IMPLEMENT_cipher(mode, fname, UCMODE, flags, kbits, blkbits, ivbits) \
284 static OSSL_FUNC_cipher_get_params_fn aes_##kbits##_##fname##_get_params; \
285 static int aes_##kbits##_##fname##_get_params(OSSL_PARAM params[]) \
286 { \
287 return ossl_cipher_generic_get_params(params, EVP_CIPH_##UCMODE##_MODE,\
288 flags, kbits, blkbits, ivbits); \
289 } \
290 static OSSL_FUNC_cipher_newctx_fn aes_##kbits##fname##_newctx; \
291 static void *aes_##kbits##fname##_newctx(void *provctx) \
292 { \
293 return aes_##mode##_newctx(kbits, blkbits, ivbits, \
294 EVP_CIPH_##UCMODE##_MODE, flags); \
295 } \
296 const OSSL_DISPATCH ossl_##aes##kbits##fname##_functions[] = { \
297 { OSSL_FUNC_CIPHER_NEWCTX, \
298 (void (*)(void))aes_##kbits##fname##_newctx }, \
299 { OSSL_FUNC_CIPHER_ENCRYPT_INIT, (void (*)(void))aes_##mode##_einit }, \
300 { OSSL_FUNC_CIPHER_DECRYPT_INIT, (void (*)(void))aes_##mode##_dinit }, \
301 { OSSL_FUNC_CIPHER_UPDATE, (void (*)(void))aes_##mode##_cipher }, \
302 { OSSL_FUNC_CIPHER_FINAL, (void (*)(void))aes_##mode##_final }, \
303 { OSSL_FUNC_CIPHER_FREECTX, (void (*)(void))aes_##mode##_freectx }, \
304 { OSSL_FUNC_CIPHER_DUPCTX, (void (*)(void))aes_##mode##_dupctx }, \
305 { OSSL_FUNC_CIPHER_GET_PARAMS, \
306 (void (*)(void))aes_##kbits##_##fname##_get_params }, \
307 { OSSL_FUNC_CIPHER_GETTABLE_PARAMS, \
308 (void (*)(void))ossl_cipher_generic_gettable_params }, \
309 { OSSL_FUNC_CIPHER_GET_CTX_PARAMS, \
310 (void (*)(void))ossl_cipher_generic_get_ctx_params }, \
311 { OSSL_FUNC_CIPHER_SET_CTX_PARAMS, \
312 (void (*)(void))aes_wrap_set_ctx_params }, \
313 { OSSL_FUNC_CIPHER_GETTABLE_CTX_PARAMS, \
314 (void (*)(void))ossl_cipher_generic_gettable_ctx_params }, \
315 { OSSL_FUNC_CIPHER_SETTABLE_CTX_PARAMS, \
316 (void (*)(void))ossl_cipher_generic_settable_ctx_params }, \
317 { 0, NULL } \
318 }
319
320 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_NOPAD_IVLEN * 8);
321 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_NOPAD_IVLEN * 8);
322 IMPLEMENT_cipher(wrap, wrap, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_NOPAD_IVLEN * 8);
323 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 256, 64, AES_WRAP_PAD_IVLEN * 8);
324 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 192, 64, AES_WRAP_PAD_IVLEN * 8);
325 IMPLEMENT_cipher(wrap, wrappad, WRAP, WRAP_FLAGS, 128, 64, AES_WRAP_PAD_IVLEN * 8);
326
327 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_NOPAD_IVLEN * 8);
328 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_NOPAD_IVLEN * 8);
329 IMPLEMENT_cipher(wrap, wrapinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_NOPAD_IVLEN * 8);
330 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 256, 64, AES_WRAP_PAD_IVLEN * 8);
331 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 192, 64, AES_WRAP_PAD_IVLEN * 8);
332 IMPLEMENT_cipher(wrap, wrappadinv, WRAP, WRAP_FLAGS_INV, 128, 64, AES_WRAP_PAD_IVLEN * 8);
333