xref: /freebsd/crypto/openssl/crypto/evp/evp_enc.c (revision 3157ba21)
1 /* crypto/evp/evp_enc.c */
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 "cryptlib.h"
61 #include <openssl/evp.h>
62 #include <openssl/err.h>
63 #include <openssl/rand.h>
64 #ifndef OPENSSL_NO_ENGINE
65 #include <openssl/engine.h>
66 #endif
67 #include "evp_locl.h"
68 
69 #ifdef OPENSSL_FIPS
70 	#define M_do_cipher(ctx, out, in, inl) \
71 		EVP_Cipher(ctx,out,in,inl)
72 #else
73 	#define M_do_cipher(ctx, out, in, inl) \
74 		ctx->cipher->do_cipher(ctx,out,in,inl)
75 #endif
76 
77 const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;
78 
79 EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)
80 	{
81 	EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx);
82 	if (ctx)
83 		EVP_CIPHER_CTX_init(ctx);
84 	return ctx;
85 	}
86 
87 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
88 	     const unsigned char *key, const unsigned char *iv, int enc)
89 	{
90 	if (cipher)
91 		EVP_CIPHER_CTX_init(ctx);
92 	return EVP_CipherInit_ex(ctx,cipher,NULL,key,iv,enc);
93 	}
94 
95 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
96 	     const unsigned char *in, int inl)
97 	{
98 	if (ctx->encrypt)
99 		return EVP_EncryptUpdate(ctx,out,outl,in,inl);
100 	else	return EVP_DecryptUpdate(ctx,out,outl,in,inl);
101 	}
102 
103 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
104 	{
105 	if (ctx->encrypt)
106 		return EVP_EncryptFinal_ex(ctx,out,outl);
107 	else	return EVP_DecryptFinal_ex(ctx,out,outl);
108 	}
109 
110 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
111 	{
112 	if (ctx->encrypt)
113 		return EVP_EncryptFinal(ctx,out,outl);
114 	else	return EVP_DecryptFinal(ctx,out,outl);
115 	}
116 
117 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
118 	     const unsigned char *key, const unsigned char *iv)
119 	{
120 	return EVP_CipherInit(ctx, cipher, key, iv, 1);
121 	}
122 
123 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,
124 		const unsigned char *key, const unsigned char *iv)
125 	{
126 	return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);
127 	}
128 
129 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,
130 	     const unsigned char *key, const unsigned char *iv)
131 	{
132 	return EVP_CipherInit(ctx, cipher, key, iv, 0);
133 	}
134 
135 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,
136 	     const unsigned char *key, const unsigned char *iv)
137 	{
138 	return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);
139 	}
140 
141 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
142 	     const unsigned char *in, int inl)
143 	{
144 	int i,j,bl;
145 
146 	if (inl <= 0)
147 		{
148 		*outl = 0;
149 		return inl == 0;
150 		}
151 
152 	if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)
153 		{
154 		if(M_do_cipher(ctx,out,in,inl))
155 			{
156 			*outl=inl;
157 			return 1;
158 			}
159 		else
160 			{
161 			*outl=0;
162 			return 0;
163 			}
164 		}
165 	i=ctx->buf_len;
166 	bl=ctx->cipher->block_size;
167 	OPENSSL_assert(bl <= (int)sizeof(ctx->buf));
168 	if (i != 0)
169 		{
170 		if (i+inl < bl)
171 			{
172 			memcpy(&(ctx->buf[i]),in,inl);
173 			ctx->buf_len+=inl;
174 			*outl=0;
175 			return 1;
176 			}
177 		else
178 			{
179 			j=bl-i;
180 			memcpy(&(ctx->buf[i]),in,j);
181 			if(!M_do_cipher(ctx,out,ctx->buf,bl)) return 0;
182 			inl-=j;
183 			in+=j;
184 			out+=bl;
185 			*outl=bl;
186 			}
187 		}
188 	else
189 		*outl = 0;
190 	i=inl&(bl-1);
191 	inl-=i;
192 	if (inl > 0)
193 		{
194 		if(!M_do_cipher(ctx,out,in,inl)) return 0;
195 		*outl+=inl;
196 		}
197 
198 	if (i != 0)
199 		memcpy(ctx->buf,&(in[inl]),i);
200 	ctx->buf_len=i;
201 	return 1;
202 	}
203 
204 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
205 	{
206 	int ret;
207 	ret = EVP_EncryptFinal_ex(ctx, out, outl);
208 	return ret;
209 	}
210 
211 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
212 	{
213 	int n,ret;
214 	unsigned int i, b, bl;
215 
216 	b=ctx->cipher->block_size;
217 	OPENSSL_assert(b <= sizeof ctx->buf);
218 	if (b == 1)
219 		{
220 		*outl=0;
221 		return 1;
222 		}
223 	bl=ctx->buf_len;
224 	if (ctx->flags & EVP_CIPH_NO_PADDING)
225 		{
226 		if(bl)
227 			{
228 			EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
229 			return 0;
230 			}
231 		*outl = 0;
232 		return 1;
233 		}
234 
235 	n=b-bl;
236 	for (i=bl; i<b; i++)
237 		ctx->buf[i]=n;
238 	ret=M_do_cipher(ctx,out,ctx->buf,b);
239 
240 
241 	if(ret)
242 		*outl=b;
243 
244 	return ret;
245 	}
246 
247 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,
248 	     const unsigned char *in, int inl)
249 	{
250 	int fix_len;
251 	unsigned int b;
252 
253 	if (inl <= 0)
254 		{
255 		*outl = 0;
256 		return inl == 0;
257 		}
258 
259 	if (ctx->flags & EVP_CIPH_NO_PADDING)
260 		return EVP_EncryptUpdate(ctx, out, outl, in, inl);
261 
262 	b=ctx->cipher->block_size;
263 	OPENSSL_assert(b <= sizeof ctx->final);
264 
265 	if(ctx->final_used)
266 		{
267 		memcpy(out,ctx->final,b);
268 		out+=b;
269 		fix_len = 1;
270 		}
271 	else
272 		fix_len = 0;
273 
274 
275 	if(!EVP_EncryptUpdate(ctx,out,outl,in,inl))
276 		return 0;
277 
278 	/* if we have 'decrypted' a multiple of block size, make sure
279 	 * we have a copy of this last block */
280 	if (b > 1 && !ctx->buf_len)
281 		{
282 		*outl-=b;
283 		ctx->final_used=1;
284 		memcpy(ctx->final,&out[*outl],b);
285 		}
286 	else
287 		ctx->final_used = 0;
288 
289 	if (fix_len)
290 		*outl += b;
291 
292 	return 1;
293 	}
294 
295 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
296 	{
297 	int ret;
298 	ret = EVP_DecryptFinal_ex(ctx, out, outl);
299 	return ret;
300 	}
301 
302 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)
303 	{
304 	int i,n;
305 	unsigned int b;
306 
307 	*outl=0;
308 	b=ctx->cipher->block_size;
309 	if (ctx->flags & EVP_CIPH_NO_PADDING)
310 		{
311 		if(ctx->buf_len)
312 			{
313 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);
314 			return 0;
315 			}
316 		*outl = 0;
317 		return 1;
318 		}
319 	if (b > 1)
320 		{
321 		if (ctx->buf_len || !ctx->final_used)
322 			{
323 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH);
324 			return(0);
325 			}
326 		OPENSSL_assert(b <= sizeof ctx->final);
327 		n=ctx->final[b-1];
328 		if (n == 0 || n > (int)b)
329 			{
330 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);
331 			return(0);
332 			}
333 		for (i=0; i<n; i++)
334 			{
335 			if (ctx->final[--b] != n)
336 				{
337 				EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);
338 				return(0);
339 				}
340 			}
341 		n=ctx->cipher->block_size-n;
342 		for (i=0; i<n; i++)
343 			out[i]=ctx->final[i];
344 		*outl=n;
345 		}
346 	else
347 		*outl=0;
348 	return(1);
349 	}
350 
351 void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)
352 	{
353 	if (ctx)
354 		{
355 		EVP_CIPHER_CTX_cleanup(ctx);
356 		OPENSSL_free(ctx);
357 		}
358 	}
359 
360 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)
361 	{
362 	if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH)
363 		return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);
364 	if(c->key_len == keylen) return 1;
365 	if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH))
366 		{
367 		c->key_len = keylen;
368 		return 1;
369 		}
370 	EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH);
371 	return 0;
372 	}
373 
374 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)
375 	{
376 	if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING;
377 	else ctx->flags |= EVP_CIPH_NO_PADDING;
378 	return 1;
379 	}
380 
381 int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)
382 	{
383 	if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)
384 		return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);
385 	if (RAND_bytes(key, ctx->key_len) <= 0)
386 		return 0;
387 	return 1;
388 	}
389 
390 #ifndef OPENSSL_NO_ENGINE
391 
392 #ifdef OPENSSL_FIPS
393 
394 static int do_evp_enc_engine_full(EVP_CIPHER_CTX *ctx, const EVP_CIPHER **pcipher, ENGINE *impl)
395 	{
396 	if(impl)
397 		{
398 		if (!ENGINE_init(impl))
399 			{
400 			EVPerr(EVP_F_DO_EVP_ENC_ENGINE_FULL, EVP_R_INITIALIZATION_ERROR);
401 			return 0;
402 			}
403 		}
404 	else
405 		/* Ask if an ENGINE is reserved for this job */
406 		impl = ENGINE_get_cipher_engine((*pcipher)->nid);
407 	if(impl)
408 		{
409 		/* There's an ENGINE for this job ... (apparently) */
410 		const EVP_CIPHER *c = ENGINE_get_cipher(impl, (*pcipher)->nid);
411 		if(!c)
412 			{
413 			/* One positive side-effect of US's export
414 			 * control history, is that we should at least
415 			 * be able to avoid using US mispellings of
416 			 * "initialisation"? */
417 			EVPerr(EVP_F_DO_EVP_ENC_ENGINE_FULL, EVP_R_INITIALIZATION_ERROR);
418 			return 0;
419 			}
420 		/* We'll use the ENGINE's private cipher definition */
421 		*pcipher = c;
422 		/* Store the ENGINE functional reference so we know
423 		 * 'cipher' came from an ENGINE and we need to release
424 		 * it when done. */
425 		ctx->engine = impl;
426 		}
427 	else
428 		ctx->engine = NULL;
429 	return 1;
430 	}
431 
432 void int_EVP_CIPHER_init_engine_callbacks(void)
433 	{
434 	int_EVP_CIPHER_set_engine_callbacks(
435 		ENGINE_finish, do_evp_enc_engine_full);
436 	}
437 
438 #endif
439 
440 #endif
441