1=pod 2 3=head1 NAME 4 5EVP_CIPHER_CTX_init, EVP_EncryptInit_ex, EVP_EncryptUpdate, 6EVP_EncryptFinal_ex, EVP_DecryptInit_ex, EVP_DecryptUpdate, 7EVP_DecryptFinal_ex, EVP_CipherInit_ex, EVP_CipherUpdate, 8EVP_CipherFinal_ex, EVP_CIPHER_CTX_set_key_length, 9EVP_CIPHER_CTX_ctrl, EVP_CIPHER_CTX_cleanup, EVP_EncryptInit, 10EVP_EncryptFinal, EVP_DecryptInit, EVP_DecryptFinal, 11EVP_CipherInit, EVP_CipherFinal, EVP_get_cipherbyname, 12EVP_get_cipherbynid, EVP_get_cipherbyobj, EVP_CIPHER_nid, 13EVP_CIPHER_block_size, EVP_CIPHER_key_length, EVP_CIPHER_iv_length, 14EVP_CIPHER_flags, EVP_CIPHER_mode, EVP_CIPHER_type, EVP_CIPHER_CTX_cipher, 15EVP_CIPHER_CTX_nid, EVP_CIPHER_CTX_block_size, EVP_CIPHER_CTX_key_length, 16EVP_CIPHER_CTX_iv_length, EVP_CIPHER_CTX_get_app_data, 17EVP_CIPHER_CTX_set_app_data, EVP_CIPHER_CTX_type, EVP_CIPHER_CTX_flags, 18EVP_CIPHER_CTX_mode, EVP_CIPHER_param_to_asn1, EVP_CIPHER_asn1_to_param, 19EVP_CIPHER_CTX_set_padding - EVP cipher routines 20 21=head1 SYNOPSIS 22 23 #include <openssl/evp.h> 24 25 void EVP_CIPHER_CTX_init(EVP_CIPHER_CTX *a); 26 27 int EVP_EncryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type, 28 ENGINE *impl, unsigned char *key, unsigned char *iv); 29 int EVP_EncryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, 30 int *outl, unsigned char *in, int inl); 31 int EVP_EncryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *out, 32 int *outl); 33 34 int EVP_DecryptInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type, 35 ENGINE *impl, unsigned char *key, unsigned char *iv); 36 int EVP_DecryptUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, 37 int *outl, unsigned char *in, int inl); 38 int EVP_DecryptFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm, 39 int *outl); 40 41 int EVP_CipherInit_ex(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type, 42 ENGINE *impl, unsigned char *key, unsigned char *iv, int enc); 43 int EVP_CipherUpdate(EVP_CIPHER_CTX *ctx, unsigned char *out, 44 int *outl, unsigned char *in, int inl); 45 int EVP_CipherFinal_ex(EVP_CIPHER_CTX *ctx, unsigned char *outm, 46 int *outl); 47 48 int EVP_EncryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type, 49 unsigned char *key, unsigned char *iv); 50 int EVP_EncryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *out, 51 int *outl); 52 53 int EVP_DecryptInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type, 54 unsigned char *key, unsigned char *iv); 55 int EVP_DecryptFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm, 56 int *outl); 57 58 int EVP_CipherInit(EVP_CIPHER_CTX *ctx, const EVP_CIPHER *type, 59 unsigned char *key, unsigned char *iv, int enc); 60 int EVP_CipherFinal(EVP_CIPHER_CTX *ctx, unsigned char *outm, 61 int *outl); 62 63 int EVP_CIPHER_CTX_set_padding(EVP_CIPHER_CTX *x, int padding); 64 int EVP_CIPHER_CTX_set_key_length(EVP_CIPHER_CTX *x, int keylen); 65 int EVP_CIPHER_CTX_ctrl(EVP_CIPHER_CTX *ctx, int type, int arg, void *ptr); 66 int EVP_CIPHER_CTX_cleanup(EVP_CIPHER_CTX *a); 67 68 const EVP_CIPHER *EVP_get_cipherbyname(const char *name); 69 #define EVP_get_cipherbynid(a) EVP_get_cipherbyname(OBJ_nid2sn(a)) 70 #define EVP_get_cipherbyobj(a) EVP_get_cipherbynid(OBJ_obj2nid(a)) 71 72 #define EVP_CIPHER_nid(e) ((e)->nid) 73 #define EVP_CIPHER_block_size(e) ((e)->block_size) 74 #define EVP_CIPHER_key_length(e) ((e)->key_len) 75 #define EVP_CIPHER_iv_length(e) ((e)->iv_len) 76 #define EVP_CIPHER_flags(e) ((e)->flags) 77 #define EVP_CIPHER_mode(e) ((e)->flags) & EVP_CIPH_MODE) 78 int EVP_CIPHER_type(const EVP_CIPHER *ctx); 79 80 #define EVP_CIPHER_CTX_cipher(e) ((e)->cipher) 81 #define EVP_CIPHER_CTX_nid(e) ((e)->cipher->nid) 82 #define EVP_CIPHER_CTX_block_size(e) ((e)->cipher->block_size) 83 #define EVP_CIPHER_CTX_key_length(e) ((e)->key_len) 84 #define EVP_CIPHER_CTX_iv_length(e) ((e)->cipher->iv_len) 85 #define EVP_CIPHER_CTX_get_app_data(e) ((e)->app_data) 86 #define EVP_CIPHER_CTX_set_app_data(e,d) ((e)->app_data=(char *)(d)) 87 #define EVP_CIPHER_CTX_type(c) EVP_CIPHER_type(EVP_CIPHER_CTX_cipher(c)) 88 #define EVP_CIPHER_CTX_flags(e) ((e)->cipher->flags) 89 #define EVP_CIPHER_CTX_mode(e) ((e)->cipher->flags & EVP_CIPH_MODE) 90 91 int EVP_CIPHER_param_to_asn1(EVP_CIPHER_CTX *c, ASN1_TYPE *type); 92 int EVP_CIPHER_asn1_to_param(EVP_CIPHER_CTX *c, ASN1_TYPE *type); 93 94=head1 DESCRIPTION 95 96The EVP cipher routines are a high level interface to certain 97symmetric ciphers. 98 99EVP_CIPHER_CTX_init() initializes cipher contex B<ctx>. 100 101EVP_EncryptInit_ex() sets up cipher context B<ctx> for encryption 102with cipher B<type> from ENGINE B<impl>. B<ctx> must be initialized 103before calling this function. B<type> is normally supplied 104by a function such as EVP_des_cbc(). If B<impl> is NULL then the 105default implementation is used. B<key> is the symmetric key to use 106and B<iv> is the IV to use (if necessary), the actual number of bytes 107used for the key and IV depends on the cipher. It is possible to set 108all parameters to NULL except B<type> in an initial call and supply 109the remaining parameters in subsequent calls, all of which have B<type> 110set to NULL. This is done when the default cipher parameters are not 111appropriate. 112 113EVP_EncryptUpdate() encrypts B<inl> bytes from the buffer B<in> and 114writes the encrypted version to B<out>. This function can be called 115multiple times to encrypt successive blocks of data. The amount 116of data written depends on the block alignment of the encrypted data: 117as a result the amount of data written may be anything from zero bytes 118to (inl + cipher_block_size - 1) so B<out> should contain sufficient 119room. The actual number of bytes written is placed in B<outl>. 120 121If padding is enabled (the default) then EVP_EncryptFinal_ex() encrypts 122the "final" data, that is any data that remains in a partial block. 123It uses L<standard block padding|/NOTES> (aka PKCS padding). The encrypted 124final data is written to B<out> which should have sufficient space for 125one cipher block. The number of bytes written is placed in B<outl>. After 126this function is called the encryption operation is finished and no further 127calls to EVP_EncryptUpdate() should be made. 128 129If padding is disabled then EVP_EncryptFinal_ex() will not encrypt any more 130data and it will return an error if any data remains in a partial block: 131that is if the total data length is not a multiple of the block size. 132 133EVP_DecryptInit_ex(), EVP_DecryptUpdate() and EVP_DecryptFinal_ex() are the 134corresponding decryption operations. EVP_DecryptFinal() will return an 135error code if padding is enabled and the final block is not correctly 136formatted. The parameters and restrictions are identical to the encryption 137operations except that if padding is enabled the decrypted data buffer B<out> 138passed to EVP_DecryptUpdate() should have sufficient room for 139(B<inl> + cipher_block_size) bytes unless the cipher block size is 1 in 140which case B<inl> bytes is sufficient. 141 142EVP_CipherInit_ex(), EVP_CipherUpdate() and EVP_CipherFinal_ex() are 143functions that can be used for decryption or encryption. The operation 144performed depends on the value of the B<enc> parameter. It should be set 145to 1 for encryption, 0 for decryption and -1 to leave the value unchanged 146(the actual value of 'enc' being supplied in a previous call). 147 148EVP_CIPHER_CTX_cleanup() clears all information from a cipher context 149and free up any allocated memory associate with it. It should be called 150after all operations using a cipher are complete so sensitive information 151does not remain in memory. 152 153EVP_EncryptInit(), EVP_DecryptInit() and EVP_CipherInit() behave in a 154similar way to EVP_EncryptInit_ex(), EVP_DecryptInit_ex and 155EVP_CipherInit_ex() except the B<ctx> parameter does not need to be 156initialized and they always use the default cipher implementation. 157 158EVP_EncryptFinal(), EVP_DecryptFinal() and EVP_CipherFinal() behave in a 159similar way to EVP_EncryptFinal_ex(), EVP_DecryptFinal_ex() and 160EVP_CipherFinal_ex() except B<ctx> is automatically cleaned up 161after the call. 162 163EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj() 164return an EVP_CIPHER structure when passed a cipher name, a NID or an 165ASN1_OBJECT structure. 166 167EVP_CIPHER_nid() and EVP_CIPHER_CTX_nid() return the NID of a cipher when 168passed an B<EVP_CIPHER> or B<EVP_CIPHER_CTX> structure. The actual NID 169value is an internal value which may not have a corresponding OBJECT 170IDENTIFIER. 171 172EVP_CIPHER_CTX_set_padding() enables or disables padding. By default 173encryption operations are padded using standard block padding and the 174padding is checked and removed when decrypting. If the B<pad> parameter 175is zero then no padding is performed, the total amount of data encrypted 176or decrypted must then be a multiple of the block size or an error will 177occur. 178 179EVP_CIPHER_key_length() and EVP_CIPHER_CTX_key_length() return the key 180length of a cipher when passed an B<EVP_CIPHER> or B<EVP_CIPHER_CTX> 181structure. The constant B<EVP_MAX_KEY_LENGTH> is the maximum key length 182for all ciphers. Note: although EVP_CIPHER_key_length() is fixed for a 183given cipher, the value of EVP_CIPHER_CTX_key_length() may be different 184for variable key length ciphers. 185 186EVP_CIPHER_CTX_set_key_length() sets the key length of the cipher ctx. 187If the cipher is a fixed length cipher then attempting to set the key 188length to any value other than the fixed value is an error. 189 190EVP_CIPHER_iv_length() and EVP_CIPHER_CTX_iv_length() return the IV 191length of a cipher when passed an B<EVP_CIPHER> or B<EVP_CIPHER_CTX>. 192It will return zero if the cipher does not use an IV. The constant 193B<EVP_MAX_IV_LENGTH> is the maximum IV length for all ciphers. 194 195EVP_CIPHER_block_size() and EVP_CIPHER_CTX_block_size() return the block 196size of a cipher when passed an B<EVP_CIPHER> or B<EVP_CIPHER_CTX> 197structure. The constant B<EVP_MAX_IV_LENGTH> is also the maximum block 198length for all ciphers. 199 200EVP_CIPHER_type() and EVP_CIPHER_CTX_type() return the type of the passed 201cipher or context. This "type" is the actual NID of the cipher OBJECT 202IDENTIFIER as such it ignores the cipher parameters and 40 bit RC2 and 203128 bit RC2 have the same NID. If the cipher does not have an object 204identifier or does not have ASN1 support this function will return 205B<NID_undef>. 206 207EVP_CIPHER_CTX_cipher() returns the B<EVP_CIPHER> structure when passed 208an B<EVP_CIPHER_CTX> structure. 209 210EVP_CIPHER_mode() and EVP_CIPHER_CTX_mode() return the block cipher mode: 211EVP_CIPH_ECB_MODE, EVP_CIPH_CBC_MODE, EVP_CIPH_CFB_MODE or 212EVP_CIPH_OFB_MODE. If the cipher is a stream cipher then 213EVP_CIPH_STREAM_CIPHER is returned. 214 215EVP_CIPHER_param_to_asn1() sets the AlgorithmIdentifier "parameter" based 216on the passed cipher. This will typically include any parameters and an 217IV. The cipher IV (if any) must be set when this call is made. This call 218should be made before the cipher is actually "used" (before any 219EVP_EncryptUpdate(), EVP_DecryptUpdate() calls for example). This function 220may fail if the cipher does not have any ASN1 support. 221 222EVP_CIPHER_asn1_to_param() sets the cipher parameters based on an ASN1 223AlgorithmIdentifier "parameter". The precise effect depends on the cipher 224In the case of RC2, for example, it will set the IV and effective key length. 225This function should be called after the base cipher type is set but before 226the key is set. For example EVP_CipherInit() will be called with the IV and 227key set to NULL, EVP_CIPHER_asn1_to_param() will be called and finally 228EVP_CipherInit() again with all parameters except the key set to NULL. It is 229possible for this function to fail if the cipher does not have any ASN1 support 230or the parameters cannot be set (for example the RC2 effective key length 231is not supported. 232 233EVP_CIPHER_CTX_ctrl() allows various cipher specific parameters to be determined 234and set. Currently only the RC2 effective key length and the number of rounds of 235RC5 can be set. 236 237=head1 RETURN VALUES 238 239EVP_EncryptInit_ex(), EVP_EncryptUpdate() and EVP_EncryptFinal_ex() 240return 1 for success and 0 for failure. 241 242EVP_DecryptInit_ex() and EVP_DecryptUpdate() return 1 for success and 0 for failure. 243EVP_DecryptFinal_ex() returns 0 if the decrypt failed or 1 for success. 244 245EVP_CipherInit_ex() and EVP_CipherUpdate() return 1 for success and 0 for failure. 246EVP_CipherFinal_ex() returns 0 for a decryption failure or 1 for success. 247 248EVP_CIPHER_CTX_cleanup() returns 1 for success and 0 for failure. 249 250EVP_get_cipherbyname(), EVP_get_cipherbynid() and EVP_get_cipherbyobj() 251return an B<EVP_CIPHER> structure or NULL on error. 252 253EVP_CIPHER_nid() and EVP_CIPHER_CTX_nid() return a NID. 254 255EVP_CIPHER_block_size() and EVP_CIPHER_CTX_block_size() return the block 256size. 257 258EVP_CIPHER_key_length() and EVP_CIPHER_CTX_key_length() return the key 259length. 260 261EVP_CIPHER_CTX_set_padding() always returns 1. 262 263EVP_CIPHER_iv_length() and EVP_CIPHER_CTX_iv_length() return the IV 264length or zero if the cipher does not use an IV. 265 266EVP_CIPHER_type() and EVP_CIPHER_CTX_type() return the NID of the cipher's 267OBJECT IDENTIFIER or NID_undef if it has no defined OBJECT IDENTIFIER. 268 269EVP_CIPHER_CTX_cipher() returns an B<EVP_CIPHER> structure. 270 271EVP_CIPHER_param_to_asn1() and EVP_CIPHER_asn1_to_param() return 1 for 272success or zero for failure. 273 274=head1 CIPHER LISTING 275 276All algorithms have a fixed key length unless otherwise stated. 277 278=over 4 279 280=item EVP_enc_null() 281 282Null cipher: does nothing. 283 284=item EVP_des_cbc(void), EVP_des_ecb(void), EVP_des_cfb(void), EVP_des_ofb(void) 285 286DES in CBC, ECB, CFB and OFB modes respectively. 287 288=item EVP_des_ede_cbc(void), EVP_des_ede(), EVP_des_ede_ofb(void), EVP_des_ede_cfb(void) 289 290Two key triple DES in CBC, ECB, CFB and OFB modes respectively. 291 292=item EVP_des_ede3_cbc(void), EVP_des_ede3(), EVP_des_ede3_ofb(void), EVP_des_ede3_cfb(void) 293 294Three key triple DES in CBC, ECB, CFB and OFB modes respectively. 295 296=item EVP_desx_cbc(void) 297 298DESX algorithm in CBC mode. 299 300=item EVP_rc4(void) 301 302RC4 stream cipher. This is a variable key length cipher with default key length 128 bits. 303 304=item EVP_rc4_40(void) 305 306RC4 stream cipher with 40 bit key length. This is obsolete and new code should use EVP_rc4() 307and the EVP_CIPHER_CTX_set_key_length() function. 308 309=item EVP_idea_cbc() EVP_idea_ecb(void), EVP_idea_cfb(void), EVP_idea_ofb(void), EVP_idea_cbc(void) 310 311IDEA encryption algorithm in CBC, ECB, CFB and OFB modes respectively. 312 313=item EVP_rc2_cbc(void), EVP_rc2_ecb(void), EVP_rc2_cfb(void), EVP_rc2_ofb(void) 314 315RC2 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key 316length cipher with an additional parameter called "effective key bits" or "effective key length". 317By default both are set to 128 bits. 318 319=item EVP_rc2_40_cbc(void), EVP_rc2_64_cbc(void) 320 321RC2 algorithm in CBC mode with a default key length and effective key length of 40 and 64 bits. 322These are obsolete and new code should use EVP_rc2_cbc(), EVP_CIPHER_CTX_set_key_length() and 323EVP_CIPHER_CTX_ctrl() to set the key length and effective key length. 324 325=item EVP_bf_cbc(void), EVP_bf_ecb(void), EVP_bf_cfb(void), EVP_bf_ofb(void); 326 327Blowfish encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key 328length cipher. 329 330=item EVP_cast5_cbc(void), EVP_cast5_ecb(void), EVP_cast5_cfb(void), EVP_cast5_ofb(void) 331 332CAST encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key 333length cipher. 334 335=item EVP_rc5_32_12_16_cbc(void), EVP_rc5_32_12_16_ecb(void), EVP_rc5_32_12_16_cfb(void), EVP_rc5_32_12_16_ofb(void) 336 337RC5 encryption algorithm in CBC, ECB, CFB and OFB modes respectively. This is a variable key length 338cipher with an additional "number of rounds" parameter. By default the key length is set to 128 339bits and 12 rounds. 340 341=back 342 343=head1 NOTES 344 345Where possible the B<EVP> interface to symmetric ciphers should be used in 346preference to the low level interfaces. This is because the code then becomes 347transparent to the cipher used and much more flexible. 348 349PKCS padding works by adding B<n> padding bytes of value B<n> to make the total 350length of the encrypted data a multiple of the block size. Padding is always 351added so if the data is already a multiple of the block size B<n> will equal 352the block size. For example if the block size is 8 and 11 bytes are to be 353encrypted then 5 padding bytes of value 5 will be added. 354 355When decrypting the final block is checked to see if it has the correct form. 356 357Although the decryption operation can produce an error if padding is enabled, 358it is not a strong test that the input data or key is correct. A random block 359has better than 1 in 256 chance of being of the correct format and problems with 360the input data earlier on will not produce a final decrypt error. 361 362If padding is disabled then the decryption operation will always succeed if 363the total amount of data decrypted is a multiple of the block size. 364 365The functions EVP_EncryptInit(), EVP_EncryptFinal(), EVP_DecryptInit(), 366EVP_CipherInit() and EVP_CipherFinal() are obsolete but are retained for 367compatibility with existing code. New code should use EVP_EncryptInit_ex(), 368EVP_EncryptFinal_ex(), EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), 369EVP_CipherInit_ex() and EVP_CipherFinal_ex() because they can reuse an 370existing context without allocating and freeing it up on each call. 371 372=head1 BUGS 373 374For RC5 the number of rounds can currently only be set to 8, 12 or 16. This is 375a limitation of the current RC5 code rather than the EVP interface. 376 377EVP_MAX_KEY_LENGTH and EVP_MAX_IV_LENGTH only refer to the internal ciphers with 378default key lengths. If custom ciphers exceed these values the results are 379unpredictable. This is because it has become standard practice to define a 380generic key as a fixed unsigned char array containing EVP_MAX_KEY_LENGTH bytes. 381 382The ASN1 code is incomplete (and sometimes inaccurate) it has only been tested 383for certain common S/MIME ciphers (RC2, DES, triple DES) in CBC mode. 384 385=head1 EXAMPLES 386 387Encrypt a string using IDEA: 388 389 int do_crypt(char *outfile) 390 { 391 unsigned char outbuf[1024]; 392 int outlen, tmplen; 393 /* Bogus key and IV: we'd normally set these from 394 * another source. 395 */ 396 unsigned char key[] = {0,1,2,3,4,5,6,7,8,9,10,11,12,13,14,15}; 397 unsigned char iv[] = {1,2,3,4,5,6,7,8}; 398 char intext[] = "Some Crypto Text"; 399 EVP_CIPHER_CTX ctx; 400 FILE *out; 401 402 EVP_CIPHER_CTX_init(&ctx); 403 EVP_EncryptInit_ex(&ctx, EVP_idea_cbc(), NULL, key, iv); 404 405 if(!EVP_EncryptUpdate(&ctx, outbuf, &outlen, intext, strlen(intext))) 406 { 407 /* Error */ 408 return 0; 409 } 410 /* Buffer passed to EVP_EncryptFinal() must be after data just 411 * encrypted to avoid overwriting it. 412 */ 413 if(!EVP_EncryptFinal_ex(&ctx, outbuf + outlen, &tmplen)) 414 { 415 /* Error */ 416 return 0; 417 } 418 outlen += tmplen; 419 EVP_CIPHER_CTX_cleanup(&ctx); 420 /* Need binary mode for fopen because encrypted data is 421 * binary data. Also cannot use strlen() on it because 422 * it wont be null terminated and may contain embedded 423 * nulls. 424 */ 425 out = fopen(outfile, "wb"); 426 fwrite(outbuf, 1, outlen, out); 427 fclose(out); 428 return 1; 429 } 430 431The ciphertext from the above example can be decrypted using the B<openssl> 432utility with the command line (shown on two lines for clarity): 433 434 openssl idea -d <filename 435 -K 000102030405060708090A0B0C0D0E0F -iv 0102030405060708 436 437General encryption and decryption function example using FILE I/O and AES128 438with a 128-bit key: 439 440 int do_crypt(FILE *in, FILE *out, int do_encrypt) 441 { 442 /* Allow enough space in output buffer for additional block */ 443 unsigned char inbuf[1024], outbuf[1024 + EVP_MAX_BLOCK_LENGTH]; 444 int inlen, outlen; 445 EVP_CIPHER_CTX ctx; 446 /* Bogus key and IV: we'd normally set these from 447 * another source. 448 */ 449 unsigned char key[] = "0123456789abcdeF"; 450 unsigned char iv[] = "1234567887654321"; 451 452 /* Don't set key or IV right away; we want to check lengths */ 453 EVP_CIPHER_CTX_init(&ctx); 454 EVP_CipherInit_ex(&ctx, EVP_aes_128_cbc(), NULL, NULL, NULL, 455 do_encrypt); 456 OPENSSL_assert(EVP_CIPHER_CTX_key_length(&ctx) == 16); 457 OPENSSL_assert(EVP_CIPHER_CTX_iv_length(&ctx) == 16); 458 459 /* Now we can set key and IV */ 460 EVP_CipherInit_ex(&ctx, NULL, NULL, key, iv, do_encrypt); 461 462 for(;;) 463 { 464 inlen = fread(inbuf, 1, 1024, in); 465 if(inlen <= 0) break; 466 if(!EVP_CipherUpdate(&ctx, outbuf, &outlen, inbuf, inlen)) 467 { 468 /* Error */ 469 EVP_CIPHER_CTX_cleanup(&ctx); 470 return 0; 471 } 472 fwrite(outbuf, 1, outlen, out); 473 } 474 if(!EVP_CipherFinal_ex(&ctx, outbuf, &outlen)) 475 { 476 /* Error */ 477 EVP_CIPHER_CTX_cleanup(&ctx); 478 return 0; 479 } 480 fwrite(outbuf, 1, outlen, out); 481 482 EVP_CIPHER_CTX_cleanup(&ctx); 483 return 1; 484 } 485 486 487=head1 SEE ALSO 488 489L<evp(3)|evp(3)> 490 491=head1 HISTORY 492 493EVP_CIPHER_CTX_init(), EVP_EncryptInit_ex(), EVP_EncryptFinal_ex(), 494EVP_DecryptInit_ex(), EVP_DecryptFinal_ex(), EVP_CipherInit_ex(), 495EVP_CipherFinal_ex() and EVP_CIPHER_CTX_set_padding() appeared in 496OpenSSL 0.9.7. 497 498IDEA appeared in OpenSSL 0.9.7 but was often disabled due to 499patent concerns; the last patents expired in 2012. 500 501=cut 502