xref: /dragonfly/crypto/libressl/crypto/evp/evp_enc.c (revision f5b1c8a1)
1 /* $OpenBSD: evp_enc.c,v 1.30 2016/05/04 15:05:13 tedu Exp $ */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
3  * All rights reserved.
4  *
5  * This package is an SSL implementation written
6  * by Eric Young (eay@cryptsoft.com).
7  * The implementation was written so as to conform with Netscapes SSL.
8  *
9  * This library is free for commercial and non-commercial use as long as
10  * the following conditions are aheared to.  The following conditions
11  * apply to all code found in this distribution, be it the RC4, RSA,
12  * lhash, DES, etc., code; not just the SSL code.  The SSL documentation
13  * included with this distribution is covered by the same copyright terms
14  * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15  *
16  * Copyright remains Eric Young's, and as such any Copyright notices in
17  * the code are not to be removed.
18  * If this package is used in a product, Eric Young should be given attribution
19  * as the author of the parts of the library used.
20  * This can be in the form of a textual message at program startup or
21  * in documentation (online or textual) provided with the package.
22  *
23  * Redistribution and use in source and binary forms, with or without
24  * modification, are permitted provided that the following conditions
25  * are met:
26  * 1. Redistributions of source code must retain the copyright
27  *    notice, this list of conditions and the following disclaimer.
28  * 2. Redistributions in binary form must reproduce the above copyright
29  *    notice, this list of conditions and the following disclaimer in the
30  *    documentation and/or other materials provided with the distribution.
31  * 3. All advertising materials mentioning features or use of this software
32  *    must display the following acknowledgement:
33  *    "This product includes cryptographic software written by
34  *     Eric Young (eay@cryptsoft.com)"
35  *    The word 'cryptographic' can be left out if the rouines from the library
36  *    being used are not cryptographic related :-).
37  * 4. If you include any Windows specific code (or a derivative thereof) from
38  *    the apps directory (application code) you must include an acknowledgement:
39  *    "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40  *
41  * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
42  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
43  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
44  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
45  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
46  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
47  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
48  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
49  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
50  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
51  * SUCH DAMAGE.
52  *
53  * The licence and distribution terms for any publically available version or
54  * derivative of this code cannot be changed.  i.e. this code cannot simply be
55  * copied and put under another distribution licence
56  * [including the GNU Public Licence.]
57  */
58 
59 #include <stdio.h>
60 #include <stdlib.h>
61 #include <string.h>
62 
63 #include <openssl/opensslconf.h>
64 
65 #include <openssl/err.h>
66 #include <openssl/evp.h>
67 
68 #ifndef OPENSSL_NO_ENGINE
69 #include <openssl/engine.h>
70 #endif
71 
72 #include "evp_locl.h"
73 
74 #define M_do_cipher(ctx, out, in, inl) ctx->cipher->do_cipher(ctx, out, in, inl)
75 
76 void
77 EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)
78 {
79 	memset(ctx, 0, sizeof(EVP_CIPHER_CTX));
80 }
81 
82 EVP_CIPHER_CTX *
83 EVP_CIPHER_CTX_new(void)
84 {
85 	return calloc(1, sizeof(EVP_CIPHER_CTX));
86 }
87 
88 int
89 EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
90     const unsigned char *key, const unsigned char *iv, int enc)
91 {
92 	if (cipher)
93 		EVP_CIPHER_CTX_init(ctx);
94 	return EVP_CipherInit_ex(ctx, cipher, NULL, key, iv, enc);
95 }
96 
97 int
98 EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
99     const unsigned char *key, const unsigned char *iv, int enc)
100 {
101 	if (enc == -1)
102 		enc = ctx->encrypt;
103 	else {
104 		if (enc)
105 			enc = 1;
106 		ctx->encrypt = enc;
107 	}
108 #ifndef OPENSSL_NO_ENGINE
109 	/* Whether it's nice or not, "Inits" can be used on "Final"'d contexts
110 	 * so this context may already have an ENGINE! Try to avoid releasing
111 	 * the previous handle, re-querying for an ENGINE, and having a
112 	 * reinitialisation, when it may all be unecessary. */
113 	if (ctx->engine && ctx->cipher &&
114 	    (!cipher || (cipher && (cipher->nid == ctx->cipher->nid))))
115 		goto skip_to_init;
116 #endif
117 	if (cipher) {
118 		/* Ensure a context left lying around from last time is cleared
119 		 * (the previous check attempted to avoid this if the same
120 		 * ENGINE and EVP_CIPHER could be used). */
121 		if (ctx->cipher) {
122 			unsigned long flags = ctx->flags;
123 			EVP_CIPHER_CTX_cleanup(ctx);
124 			/* Restore encrypt and flags */
125 			ctx->encrypt = enc;
126 			ctx->flags = flags;
127 		}
128 #ifndef OPENSSL_NO_ENGINE
129 		if (impl) {
130 			if (!ENGINE_init(impl)) {
131 				EVPerr(EVP_F_EVP_CIPHERINIT_EX,
132 				    EVP_R_INITIALIZATION_ERROR);
133 				return 0;
134 			}
135 		} else
136 			/* Ask if an ENGINE is reserved for this job */
137 			impl = ENGINE_get_cipher_engine(cipher->nid);
138 		if (impl) {
139 			/* There's an ENGINE for this job ... (apparently) */
140 			const EVP_CIPHER *c =
141 			    ENGINE_get_cipher(impl, cipher->nid);
142 			if (!c) {
143 				EVPerr(EVP_F_EVP_CIPHERINIT_EX,
144 				    EVP_R_INITIALIZATION_ERROR);
145 				return 0;
146 			}
147 			/* We'll use the ENGINE's private cipher definition */
148 			cipher = c;
149 			/* Store the ENGINE functional reference so we know
150 			 * 'cipher' came from an ENGINE and we need to release
151 			 * it when done. */
152 			ctx->engine = impl;
153 		} else
154 			ctx->engine = NULL;
155 #endif
156 
157 		ctx->cipher = cipher;
158 		if (ctx->cipher->ctx_size) {
159 			ctx->cipher_data = malloc(ctx->cipher->ctx_size);
160 			if (!ctx->cipher_data) {
161 				EVPerr(EVP_F_EVP_CIPHERINIT_EX,
162 				    ERR_R_MALLOC_FAILURE);
163 				return 0;
164 			}
165 		} else {
166 			ctx->cipher_data = NULL;
167 		}
168 		ctx->key_len = cipher->key_len;
169 		ctx->flags = 0;
170 		if (ctx->cipher->flags & EVP_CIPH_CTRL_INIT) {
171 			if (!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL)) {
172 				EVPerr(EVP_F_EVP_CIPHERINIT_EX,
173 				    EVP_R_INITIALIZATION_ERROR);
174 				return 0;
175 			}
176 		}
177 	} else if (!ctx->cipher) {
178 		EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);
179 		return 0;
180 	}
181 #ifndef OPENSSL_NO_ENGINE
182 skip_to_init:
183 #endif
184 	/* we assume block size is a power of 2 in *cryptUpdate */
185 	if (ctx->cipher->block_size != 1 &&
186 	    ctx->cipher->block_size != 8 &&
187 	    ctx->cipher->block_size != 16) {
188 		EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_BAD_BLOCK_LENGTH);
189 		return 0;
190 	}
191 
192 	if (!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {
193 		switch (EVP_CIPHER_CTX_mode(ctx)) {
194 
195 		case EVP_CIPH_STREAM_CIPHER:
196 		case EVP_CIPH_ECB_MODE:
197 			break;
198 
199 		case EVP_CIPH_CFB_MODE:
200 		case EVP_CIPH_OFB_MODE:
201 
202 			ctx->num = 0;
203 			/* fall-through */
204 
205 		case EVP_CIPH_CBC_MODE:
206 
207 			if ((size_t)EVP_CIPHER_CTX_iv_length(ctx) >
208 			    sizeof(ctx->iv)) {
209 				EVPerr(EVP_F_EVP_CIPHERINIT_EX,
210 				    EVP_R_IV_TOO_LARGE);
211 				return 0;
212 			}
213 			if (iv)
214 				memcpy(ctx->oiv, iv,
215 				    EVP_CIPHER_CTX_iv_length(ctx));
216 			memcpy(ctx->iv, ctx->oiv,
217 			    EVP_CIPHER_CTX_iv_length(ctx));
218 			break;
219 
220 		case EVP_CIPH_CTR_MODE:
221 			ctx->num = 0;
222 			/* Don't reuse IV for CTR mode */
223 			if (iv)
224 				memcpy(ctx->iv, iv,
225 				    EVP_CIPHER_CTX_iv_length(ctx));
226 			break;
227 
228 		default:
229 			return 0;
230 			break;
231 		}
232 	}
233 
234 	if (key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {
235 		if (!ctx->cipher->init(ctx, key, iv, enc))
236 			return 0;
237 	}
238 	ctx->buf_len = 0;
239 	ctx->final_used = 0;
240 	ctx->block_mask = ctx->cipher->block_size - 1;
241 	return 1;
242 }
243 
244 int
245 EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
246     const unsigned char *in, int inl)
247 {
248 	if (ctx->encrypt)
249 		return EVP_EncryptUpdate(ctx, out, outl, in, inl);
250 	else
251 		return EVP_DecryptUpdate(ctx, out, outl, in, inl);
252 }
253 
254 int
255 EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
256 {
257 	if (ctx->encrypt)
258 		return EVP_EncryptFinal_ex(ctx, out, outl);
259 	else
260 		return EVP_DecryptFinal_ex(ctx, out, outl);
261 }
262 
263 int
264 EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
265 {
266 	if (ctx->encrypt)
267 		return EVP_EncryptFinal_ex(ctx, out, outl);
268 	else
269 		return EVP_DecryptFinal_ex(ctx, out, outl);
270 }
271 
272 int
273 EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
274     const unsigned char *key, const unsigned char *iv)
275 {
276 	return EVP_CipherInit(ctx, cipher, key, iv, 1);
277 }
278 
279 int
280 EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
281     const unsigned char *key, const unsigned char *iv)
282 {
283 	return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
284 }
285 
286 int
287 EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
288     const unsigned char *key, const unsigned char *iv)
289 {
290 	return EVP_CipherInit(ctx, cipher, key, iv, 0);
291 }
292 
293 int
294 EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
295     const unsigned char *key, const unsigned char *iv)
296 {
297 	return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
298 }
299 
300 int
301 EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
302     const unsigned char *in, int inl)
303 {
304 	int i, j, bl;
305 
306 	if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
307 		i = M_do_cipher(ctx, out, in, inl);
308 		if (i < 0)
309 			return 0;
310 		else
311 			*outl = i;
312 		return 1;
313 	}
314 
315 	if (inl <= 0) {
316 		*outl = 0;
317 		return inl == 0;
318 	}
319 
320 	if (ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0) {
321 		if (M_do_cipher(ctx, out, in, inl)) {
322 			*outl = inl;
323 			return 1;
324 		} else {
325 			*outl = 0;
326 			return 0;
327 		}
328 	}
329 	i = ctx->buf_len;
330 	bl = ctx->cipher->block_size;
331 	if ((size_t)bl > sizeof(ctx->buf)) {
332 		EVPerr(EVP_F_EVP_ENCRYPTUPDATE, EVP_R_BAD_BLOCK_LENGTH);
333 		*outl = 0;
334 		return 0;
335 	}
336 	if (i != 0) {
337 		if (bl - i > inl) {
338 			memcpy(&(ctx->buf[i]), in, inl);
339 			ctx->buf_len += inl;
340 			*outl = 0;
341 			return 1;
342 		} else {
343 			j = bl - i;
344 			memcpy(&(ctx->buf[i]), in, j);
345 			if (!M_do_cipher(ctx, out, ctx->buf, bl))
346 				return 0;
347 			inl -= j;
348 			in += j;
349 			out += bl;
350 			*outl = bl;
351 		}
352 	} else
353 		*outl = 0;
354 	i = inl&(bl - 1);
355 	inl -= i;
356 	if (inl > 0) {
357 		if (!M_do_cipher(ctx, out, in, inl))
358 			return 0;
359 		*outl += inl;
360 	}
361 
362 	if (i != 0)
363 		memcpy(ctx->buf, &(in[inl]), i);
364 	ctx->buf_len = i;
365 	return 1;
366 }
367 
368 int
369 EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
370 {
371 	int ret;
372 
373 	ret = EVP_EncryptFinal_ex(ctx, out, outl);
374 	(void) EVP_CIPHER_CTX_cleanup(ctx);
375 	return ret;
376 }
377 
378 int
379 EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
380 {
381 	int n, ret;
382 	unsigned int i, b, bl;
383 
384 	if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
385 		ret = M_do_cipher(ctx, out, NULL, 0);
386 		if (ret < 0)
387 			return 0;
388 		else
389 			*outl = ret;
390 		return 1;
391 	}
392 
393 	b = ctx->cipher->block_size;
394 	if (b > sizeof ctx->buf) {
395 		EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX, EVP_R_BAD_BLOCK_LENGTH);
396 		return 0;
397 	}
398 	if (b == 1) {
399 		*outl = 0;
400 		return 1;
401 	}
402 	bl = ctx->buf_len;
403 	if (ctx->flags & EVP_CIPH_NO_PADDING) {
404 		if (bl) {
405 			EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,
406 			    EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
407 			return 0;
408 		}
409 		*outl = 0;
410 		return 1;
411 	}
412 
413 	n = b - bl;
414 	for (i = bl; i < b; i++)
415 		ctx->buf[i] = n;
416 	ret = M_do_cipher(ctx, out, ctx->buf, b);
417 
418 
419 	if (ret)
420 		*outl = b;
421 
422 	return ret;
423 }
424 
425 int
426 EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
427     const unsigned char *in, int inl)
428 {
429 	int fix_len;
430 	unsigned int b;
431 
432 	if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
433 		fix_len = M_do_cipher(ctx, out, in, inl);
434 		if (fix_len < 0) {
435 			*outl = 0;
436 			return 0;
437 		} else
438 			*outl = fix_len;
439 		return 1;
440 	}
441 
442 	if (inl <= 0) {
443 		*outl = 0;
444 		return inl == 0;
445 	}
446 
447 	if (ctx->flags & EVP_CIPH_NO_PADDING)
448 		return EVP_EncryptUpdate(ctx, out, outl, in, inl);
449 
450 	b = ctx->cipher->block_size;
451 	if (b > sizeof ctx->final) {
452 		EVPerr(EVP_F_EVP_DECRYPTUPDATE, EVP_R_BAD_BLOCK_LENGTH);
453 		return 0;
454 	}
455 
456 	if (ctx->final_used) {
457 		memcpy(out, ctx->final, b);
458 		out += b;
459 		fix_len = 1;
460 	} else
461 		fix_len = 0;
462 
463 
464 	if (!EVP_EncryptUpdate(ctx, out, outl, in, inl))
465 		return 0;
466 
467 	/* if we have 'decrypted' a multiple of block size, make sure
468 	 * we have a copy of this last block */
469 	if (b > 1 && !ctx->buf_len) {
470 		*outl -= b;
471 		ctx->final_used = 1;
472 		memcpy(ctx->final, &out[*outl], b);
473 	} else
474 		ctx->final_used = 0;
475 
476 	if (fix_len)
477 		*outl += b;
478 
479 	return 1;
480 }
481 
482 int
483 EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
484 {
485 	int ret;
486 
487 	ret = EVP_DecryptFinal_ex(ctx, out, outl);
488 	(void) EVP_CIPHER_CTX_cleanup(ctx);
489 	return ret;
490 }
491 
492 int
493 EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
494 {
495 	int i, n;
496 	unsigned int b;
497 	*outl = 0;
498 
499 	if (ctx->cipher->flags & EVP_CIPH_FLAG_CUSTOM_CIPHER) {
500 		i = M_do_cipher(ctx, out, NULL, 0);
501 		if (i < 0)
502 			return 0;
503 		else
504 			*outl = i;
505 		return 1;
506 	}
507 
508 	b = ctx->cipher->block_size;
509 	if (ctx->flags & EVP_CIPH_NO_PADDING) {
510 		if (ctx->buf_len) {
511 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
512 			    EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
513 			return 0;
514 		}
515 		*outl = 0;
516 		return 1;
517 	}
518 	if (b > 1) {
519 		if (ctx->buf_len || !ctx->final_used) {
520 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
521 			    EVP_R_WRONG_FINAL_BLOCK_LENGTH);
522 			return (0);
523 		}
524 		if (b > sizeof ctx->final) {
525 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
526 			    EVP_R_BAD_BLOCK_LENGTH);
527 			return 0;
528 		}
529 		n = ctx->final[b - 1];
530 		if (n == 0 || n > (int)b) {
531 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX, EVP_R_BAD_DECRYPT);
532 			return (0);
533 		}
534 		for (i = 0; i < n; i++) {
535 			if (ctx->final[--b] != n) {
536 				EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,
537 				    EVP_R_BAD_DECRYPT);
538 				return (0);
539 			}
540 		}
541 		n = ctx->cipher->block_size - n;
542 		for (i = 0; i < n; i++)
543 			out[i] = ctx->final[i];
544 		*outl = n;
545 	} else
546 		*outl = 0;
547 	return (1);
548 }
549 
550 void
551 EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
552 {
553 	if (ctx) {
554 		EVP_CIPHER_CTX_cleanup(ctx);
555 		free(ctx);
556 	}
557 }
558 
559 int
560 EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)
561 {
562 	if (c->cipher != NULL) {
563 		if (c->cipher->cleanup && !c->cipher->cleanup(c))
564 			return 0;
565 		/* Cleanse cipher context data */
566 		if (c->cipher_data)
567 			explicit_bzero(c->cipher_data, c->cipher->ctx_size);
568 	}
569 	free(c->cipher_data);
570 #ifndef OPENSSL_NO_ENGINE
571 	if (c->engine)
572 		/* The EVP_CIPHER we used belongs to an ENGINE, release the
573 		 * functional reference we held for this reason. */
574 		ENGINE_finish(c->engine);
575 #endif
576 	explicit_bzero(c, sizeof(EVP_CIPHER_CTX));
577 	return 1;
578 }
579 
580 int
581 EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
582 {
583 	if (c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
584 		return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH,
585 		    keylen, NULL);
586 	if (c->key_len == keylen)
587 		return 1;
588 	if ((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH)) {
589 		c->key_len = keylen;
590 		return 1;
591 	}
592 	EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH, EVP_R_INVALID_KEY_LENGTH);
593 	return 0;
594 }
595 
596 int
597 EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
598 {
599 	if (pad)
600 		ctx->flags &= ~EVP_CIPH_NO_PADDING;
601 	else
602 		ctx->flags |= EVP_CIPH_NO_PADDING;
603 	return 1;
604 }
605 
606 int
607 EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)
608 {
609 	int ret;
610 
611 	if (!ctx->cipher) {
612 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);
613 		return 0;
614 	}
615 
616 	if (!ctx->cipher->ctrl) {
617 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);
618 		return 0;
619 	}
620 
621 	ret = ctx->cipher->ctrl(ctx, type, arg, ptr);
622 	if (ret == -1) {
623 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL,
624 		    EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);
625 		return 0;
626 	}
627 	return ret;
628 }
629 
630 int
631 EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
632 {
633 	if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
634 		return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
635 	arc4random_buf(key, ctx->key_len);
636 	return 1;
637 }
638 
639 int
640 EVP_CIPHER_CTX_copy(EVP_CIPHER_CTX *out, const EVP_CIPHER_CTX *in)
641 {
642 	if ((in == NULL) || (in->cipher == NULL)) {
643 		EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, EVP_R_INPUT_NOT_INITIALIZED);
644 		return 0;
645 	}
646 #ifndef OPENSSL_NO_ENGINE
647 	/* Make sure it's safe to copy a cipher context using an ENGINE */
648 	if (in->engine && !ENGINE_init(in->engine)) {
649 		EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_ENGINE_LIB);
650 		return 0;
651 	}
652 #endif
653 
654 	EVP_CIPHER_CTX_cleanup(out);
655 	memcpy(out, in, sizeof *out);
656 
657 	if (in->cipher_data && in->cipher->ctx_size) {
658 		out->cipher_data = malloc(in->cipher->ctx_size);
659 		if (!out->cipher_data) {
660 			EVPerr(EVP_F_EVP_CIPHER_CTX_COPY, ERR_R_MALLOC_FAILURE);
661 			return 0;
662 		}
663 		memcpy(out->cipher_data, in->cipher_data, in->cipher->ctx_size);
664 	}
665 
666 	if (in->cipher->flags & EVP_CIPH_CUSTOM_COPY)
667 		return in->cipher->ctrl((EVP_CIPHER_CTX *)in,
668 		    EVP_CTRL_COPY, 0, out);
669 	return 1;
670 }
671