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 const char EVP_version[]="EVP" OPENSSL_VERSION_PTEXT;

    70 

    71 EXPORT_C void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *ctx)

    72 	{

    73 	memset(ctx,0,sizeof(EVP_CIPHER_CTX));

    74 	/* ctx->cipher=NULL; */

    75 	}

    76 

    77 EXPORT_C EVP_CIPHER_CTX *EVP_CIPHER_CTX_new(void)

    78 	{

    79 	EVP_CIPHER_CTX *ctx=OPENSSL_malloc(sizeof *ctx);

    80 	if (ctx)

    81 		EVP_CIPHER_CTX_init(ctx);

    82 	return ctx;

    83 	}

    84 

    85 EXPORT_C int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,

    86 	     const unsigned char *key, const unsigned char *iv, int enc)

    87 	{

    88 	if (cipher)

    89 		EVP_CIPHER_CTX_init(ctx);

    90 	return EVP_CipherInit_ex(ctx,cipher,NULL,key,iv,enc);

    91 	}

    92 

    93 EXPORT_C int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,

    94 	     const unsigned char *key, const unsigned char *iv, int enc)

    95 	{

    96 	if (enc == -1)

    97 		enc = ctx->encrypt;

    98 	else

    99 		{

   100 		if (enc)

   101 			enc = 1;

   102 		ctx->encrypt = enc;

   103 		}

   104 #ifndef OPENSSL_NO_ENGINE

   105 	/* Whether it's nice or not, "Inits" can be used on "Final"'d contexts

   106 	 * so this context may already have an ENGINE! Try to avoid releasing

   107 	 * the previous handle, re-querying for an ENGINE, and having a

   108 	 * reinitialisation, when it may all be unecessary. */

   109 	if (ctx->engine && ctx->cipher && (!cipher ||

   110 			(cipher && (cipher->nid == ctx->cipher->nid))))

   111 		goto skip_to_init;

   112 #endif

   113 	if (cipher)

   114 		{

   115 		/* Ensure a context left lying around from last time is cleared

   116 		 * (the previous check attempted to avoid this if the same

   117 		 * ENGINE and EVP_CIPHER could be used). */

   118 		EVP_CIPHER_CTX_cleanup(ctx);

   119 

   120 		/* Restore encrypt field: it is zeroed by cleanup */

   121 		ctx->encrypt = enc;

   122 #ifndef OPENSSL_NO_ENGINE

   123 		if(impl)

   124 			{

   125 			if (!ENGINE_init(impl))

   126 				{

   127 				EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);

   128 				return 0;

   129 				}

   130 			}

   131 		else

   132 			/* Ask if an ENGINE is reserved for this job */

   133 			impl = ENGINE_get_cipher_engine(cipher->nid);

   134 		if(impl)

   135 			{

   136 			/* There's an ENGINE for this job ... (apparently) */

   137 			const EVP_CIPHER *c = ENGINE_get_cipher(impl, cipher->nid);

   138 			if(!c)

   139 				{

   140 				/* One positive side-effect of US's export

   141 				 * control history, is that we should at least

   142 				 * be able to avoid using US mispellings of

   143 				 * "initialisation"? */

   144 				EVPerr(EVP_F_EVP_CIPHERINIT_EX, 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 			}

   154 		else

   155 			ctx->engine = NULL;

   156 #endif

   157 

   158 		ctx->cipher=cipher;

   159 		if (ctx->cipher->ctx_size)

   160 			{

   161 			ctx->cipher_data=OPENSSL_malloc(ctx->cipher->ctx_size);

   162 			if (!ctx->cipher_data)

   163 				{

   164 				EVPerr(EVP_F_EVP_CIPHERINIT_EX, ERR_R_MALLOC_FAILURE);

   165 				return 0;

   166 				}

   167 			}

   168 		else

   169 			{

   170 			ctx->cipher_data = NULL;

   171 			}

   172 		ctx->key_len = cipher->key_len;

   173 		ctx->flags = 0;

   174 		if(ctx->cipher->flags & EVP_CIPH_CTRL_INIT)

   175 			{

   176 			if(!EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_INIT, 0, NULL))

   177 				{

   178 				EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_INITIALIZATION_ERROR);

   179 				return 0;

   180 				}

   181 			}

   182 		}

   183 	else if(!ctx->cipher)

   184 		{

   185 		EVPerr(EVP_F_EVP_CIPHERINIT_EX, EVP_R_NO_CIPHER_SET);

   186 		return 0;

   187 		}

   188 #ifndef OPENSSL_NO_ENGINE

   189 skip_to_init:

   190 #endif

   191 	/* we assume block size is a power of 2 in *cryptUpdate */

   192 	OPENSSL_assert(ctx->cipher->block_size == 1

   193 	    || ctx->cipher->block_size == 8

   194 	    || ctx->cipher->block_size == 16);

   195 

   196 	if(!(EVP_CIPHER_CTX_flags(ctx) & EVP_CIPH_CUSTOM_IV)) {

   197 		switch(EVP_CIPHER_CTX_mode(ctx)) {

   198 

   199 			case EVP_CIPH_STREAM_CIPHER:

   200 			case EVP_CIPH_ECB_MODE:

   201 			break;

   202 

   203 			case EVP_CIPH_CFB_MODE:

   204 			case EVP_CIPH_OFB_MODE:

   205 

   206 			ctx->num = 0;

   207 

   208 			case EVP_CIPH_CBC_MODE:

   209 

   210 			OPENSSL_assert(EVP_CIPHER_CTX_iv_length(ctx) <=

   211 					(int)sizeof(ctx->iv));

   212 			if(iv) memcpy(ctx->oiv, iv, EVP_CIPHER_CTX_iv_length(ctx));

   213 			memcpy(ctx->iv, ctx->oiv, EVP_CIPHER_CTX_iv_length(ctx));

   214 			break;

   215 

   216 			default:

   217 			return 0;

   218 			break;

   219 		}

   220 	}

   221 

   222 	if(key || (ctx->cipher->flags & EVP_CIPH_ALWAYS_CALL_INIT)) {

   223 		if(!ctx->cipher->init(ctx,key,iv,enc)) return 0;

   224 	}

   225 	ctx->buf_len=0;

   226 	ctx->final_used=0;

   227 	ctx->block_mask=ctx->cipher->block_size-1;

   228 	return 1;

   229 	}

   230 

   231 EXPORT_C int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,

   232 	     const unsigned char *in, int inl)

   233 	{

   234 	if (ctx->encrypt)

   235 		return EVP_EncryptUpdate(ctx,out,outl,in,inl);

   236 	else	return EVP_DecryptUpdate(ctx,out,outl,in,inl);

   237 	}

   238 

   239 EXPORT_C int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

   240 	{

   241 	if (ctx->encrypt)

   242 		return EVP_EncryptFinal_ex(ctx,out,outl);

   243 	else	return EVP_DecryptFinal_ex(ctx,out,outl);

   244 	}

   245 

   246 EXPORT_C int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

   247 	{

   248 	if (ctx->encrypt)

   249 		return EVP_EncryptFinal(ctx,out,outl);

   250 	else	return EVP_DecryptFinal(ctx,out,outl);

   251 	}

   252 

   253 EXPORT_C int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,

   254 	     const unsigned char *key, const unsigned char *iv)

   255 	{

   256 	return EVP_CipherInit(ctx, cipher, key, iv, 1);

   257 	}

   258 

   259 EXPORT_C int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx,const EVP_CIPHER *cipher, ENGINE *impl,

   260 		const unsigned char *key, const unsigned char *iv)

   261 	{

   262 	return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 1);

   263 	}

   264 

   265 EXPORT_C int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher,

   266 	     const unsigned char *key, const unsigned char *iv)

   267 	{

   268 	return EVP_CipherInit(ctx, cipher, key, iv, 0);

   269 	}

   270 

   271 EXPORT_C int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *cipher, ENGINE *impl,

   272 	     const unsigned char *key, const unsigned char *iv)

   273 	{

   274 	return EVP_CipherInit_ex(ctx, cipher, impl, key, iv, 0);

   275 	}

   276 

   277 EXPORT_C int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,

   278 	     const unsigned char *in, int inl)

   279 	{

   280 	int i,j,bl;

   281 

   282 	OPENSSL_assert(inl > 0);

   283 	if(ctx->buf_len == 0 && (inl&(ctx->block_mask)) == 0)

   284 		{

   285 		if(ctx->cipher->do_cipher(ctx,out,in,inl))

   286 			{

   287 			*outl=inl;

   288 			return 1;

   289 			}

   290 		else

   291 			{

   292 			*outl=0;

   293 			return 0;

   294 			}

   295 		}

   296 	i=ctx->buf_len;

   297 	bl=ctx->cipher->block_size;

   298 	OPENSSL_assert(bl <= (int)sizeof(ctx->buf));

   299 	if (i != 0)

   300 		{

   301 		if (i+inl < bl)

   302 			{

   303 			memcpy(&(ctx->buf[i]),in,inl);

   304 			ctx->buf_len+=inl;

   305 			*outl=0;

   306 			return 1;

   307 			}

   308 		else

   309 			{

   310 			j=bl-i;

   311 			memcpy(&(ctx->buf[i]),in,j);

   312 			if(!ctx->cipher->do_cipher(ctx,out,ctx->buf,bl)) return 0;

   313 			inl-=j;

   314 			in+=j;

   315 			out+=bl;

   316 			*outl=bl;

   317 			}

   318 		}

   319 	else

   320 		*outl = 0;

   321 	i=inl&(bl-1);

   322 	inl-=i;

   323 	if (inl > 0)

   324 		{

   325 		if(!ctx->cipher->do_cipher(ctx,out,in,inl)) return 0;

   326 		*outl+=inl;

   327 		}

   328 

   329 	if (i != 0)

   330 		memcpy(ctx->buf,&(in[inl]),i);

   331 	ctx->buf_len=i;

   332 	return 1;

   333 	}

   334 

   335 EXPORT_C int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

   336 	{

   337 	int ret;

   338 	ret = EVP_EncryptFinal_ex(ctx, out, outl);

   339 	return ret;

   340 	}

   341 

   342 EXPORT_C int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

   343 	{

   344 	int n,ret;

   345 	unsigned int i, b, bl;

   346 

   347 	b=ctx->cipher->block_size;

   348 	OPENSSL_assert(b <= sizeof ctx->buf);

   349 	if (b == 1)

   350 		{

   351 		*outl=0;

   352 		return 1;

   353 		}

   354 	bl=ctx->buf_len;

   355 	if (ctx->flags & EVP_CIPH_NO_PADDING)

   356 		{

   357 		if(bl)

   358 			{

   359 			EVPerr(EVP_F_EVP_ENCRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);

   360 			return 0;

   361 			}

   362 		*outl = 0;

   363 		return 1;

   364 		}

   365 

   366 	n=b-bl;

   367 	for (i=bl; i<b; i++)

   368 		ctx->buf[i]=n;

   369 	ret=ctx->cipher->do_cipher(ctx,out,ctx->buf,b);

   370 

   371 

   372 	if(ret)

   373 		*outl=b;

   374 

   375 	return ret;

   376 	}

   377 

   378 EXPORT_C int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl,

   379 	     const unsigned char *in, int inl)

   380 	{

   381 	int fix_len;

   382 	unsigned int b;

   383 

   384 	if (inl == 0)

   385 		{

   386 		*outl=0;

   387 		return 1;

   388 		}

   389 

   390 	if (ctx->flags & EVP_CIPH_NO_PADDING)

   391 		return EVP_EncryptUpdate(ctx, out, outl, in, inl);

   392 

   393 	b=ctx->cipher->block_size;

   394 	OPENSSL_assert(b <= sizeof ctx->final);

   395 

   396 	if(ctx->final_used)

   397 		{

   398 		memcpy(out,ctx->final,b);

   399 		out+=b;

   400 		fix_len = 1;

   401 		}

   402 	else

   403 		fix_len = 0;

   404 

   405 

   406 	if(!EVP_EncryptUpdate(ctx,out,outl,in,inl))

   407 		return 0;

   408 

   409 	/* if we have 'decrypted' a multiple of block size, make sure

   410 	 * we have a copy of this last block */

   411 	if (b > 1 && !ctx->buf_len)

   412 		{

   413 		*outl-=b;

   414 		ctx->final_used=1;

   415 		memcpy(ctx->final,&out[*outl],b);

   416 		}

   417 	else

   418 		ctx->final_used = 0;

   419 

   420 	if (fix_len)

   421 		*outl += b;

   422 		

   423 	return 1;

   424 	}

   425 

   426 EXPORT_C int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

   427 	{

   428 	int ret;

   429 	ret = EVP_DecryptFinal_ex(ctx, out, outl);

   430 	return ret;

   431 	}

   432 

   433 EXPORT_C int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, int *outl)

   434 	{

   435 	int i,n;

   436 	unsigned int b;

   437 

   438 	*outl=0;

   439 	b=ctx->cipher->block_size;

   440 	if (ctx->flags & EVP_CIPH_NO_PADDING)

   441 		{

   442 		if(ctx->buf_len)

   443 			{

   444 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_DATA_NOT_MULTIPLE_OF_BLOCK_LENGTH);

   445 			return 0;

   446 			}

   447 		*outl = 0;

   448 		return 1;

   449 		}

   450 	if (b > 1)

   451 		{

   452 		if (ctx->buf_len || !ctx->final_used)

   453 			{

   454 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_WRONG_FINAL_BLOCK_LENGTH);

   455 			return(0);

   456 			}

   457 		OPENSSL_assert(b <= sizeof ctx->final);

   458 		n=ctx->final[b-1];

   459 		if (n == 0 || n > (int)b)

   460 			{

   461 			EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);

   462 			return(0);

   463 			}

   464 		for (i=0; i<n; i++)

   465 			{

   466 			if (ctx->final[--b] != n)

   467 				{

   468 				EVPerr(EVP_F_EVP_DECRYPTFINAL_EX,EVP_R_BAD_DECRYPT);

   469 				return(0);

   470 				}

   471 			}

   472 		n=ctx->cipher->block_size-n;

   473 		for (i=0; i<n; i++)

   474 			out[i]=ctx->final[i];

   475 		*outl=n;

   476 		}

   477 	else

   478 		*outl=0;

   479 	return(1);

   480 	}

   481 

   482 EXPORT_C void EVP_CIPHER_CTX_free(EVP_CIPHER_CTX *ctx)

   483 	{

   484 	if (ctx)

   485 		{

   486 		EVP_CIPHER_CTX_cleanup(ctx);

   487 		OPENSSL_free(ctx);

   488 		}

   489 	}

   490 EXPORT_C int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *c)

   491 	{

   492 	if (c->cipher != NULL)

   493 		{

   494 		if(c->cipher->cleanup && !c->cipher->cleanup(c))

   495 			return 0;

   496 		/* Cleanse cipher context data */

   497 		if (c->cipher_data)

   498 			OPENSSL_cleanse(c->cipher_data, c->cipher->ctx_size);

   499 		}

   500 	if (c->cipher_data)

   501 		OPENSSL_free(c->cipher_data);

   502 #ifndef OPENSSL_NO_ENGINE

   503 	if (c->engine)

   504 		/* The EVP_CIPHER we used belongs to an ENGINE, release the

   505 		 * functional reference we held for this reason. */

   506 		ENGINE_finish(c->engine);

   507 #endif

   508 	memset(c,0,sizeof(EVP_CIPHER_CTX));

   509 	return 1;

   510 	}

   511 

   512 EXPORT_C int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *c, int keylen)

   513 	{

   514 	if(c->cipher->flags & EVP_CIPH_CUSTOM_KEY_LENGTH) 

   515 		return EVP_CIPHER_CTX_ctrl(c, EVP_CTRL_SET_KEY_LENGTH, keylen, NULL);

   516 	if(c->key_len == keylen) return 1;

   517 	if((keylen > 0) && (c->cipher->flags & EVP_CIPH_VARIABLE_LENGTH))

   518 		{

   519 		c->key_len = keylen;

   520 		return 1;

   521 		}

   522 	EVPerr(EVP_F_EVP_CIPHER_CTX_SET_KEY_LENGTH,EVP_R_INVALID_KEY_LENGTH);

   523 	return 0;

   524 	}

   525 

   526 EXPORT_C int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *ctx, int pad)

   527 	{

   528 	if (pad) ctx->flags &= ~EVP_CIPH_NO_PADDING;

   529 	else ctx->flags |= EVP_CIPH_NO_PADDING;

   530 	return 1;

   531 	}

   532 

   533 EXPORT_C int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr)

   534 {

   535 	int ret;

   536 	if(!ctx->cipher) {

   537 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_NO_CIPHER_SET);

   538 		return 0;

   539 	}

   540 

   541 	if(!ctx->cipher->ctrl) {

   542 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_NOT_IMPLEMENTED);

   543 		return 0;

   544 	}

   545 

   546 	ret = ctx->cipher->ctrl(ctx, type, arg, ptr);

   547 	if(ret == -1) {

   548 		EVPerr(EVP_F_EVP_CIPHER_CTX_CTRL, EVP_R_CTRL_OPERATION_NOT_IMPLEMENTED);

   549 		return 0;

   550 	}

   551 	return ret;

   552 }

   553 

   554 EXPORT_C int EVP_CIPHER_CTX_rand_key(EVP_CIPHER_CTX *ctx, unsigned char *key)

   555 	{

   556 	if (ctx->cipher->flags & EVP_CIPH_RAND_KEY)

   557 		return EVP_CIPHER_CTX_ctrl(ctx, EVP_CTRL_RAND_KEY, 0, key);

   558 	if (RAND_bytes(key, ctx->key_len) <= 0)

   559 		return 0;

   560 	return 1;

   561 	}

   562