usr/src/common/openssl/crypto/evp/bio_enc.c

   1 /* crypto/evp/bio_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 <errno.h>
  61 #include "cryptlib.h"
  62 #include <openssl/buffer.h>
  63 #include <openssl/evp.h>
  64
  65 static int enc_write(BIO *h, const char *buf, int num);
  66 static int enc_read(BIO *h, char *buf, int size);
  67 /*static int enc_puts(BIO *h, const char *str); */
  68 /*static int enc_gets(BIO *h, char *str, int size); */
  69 static long enc_ctrl(BIO *h, int cmd, long arg1, void *arg2);
  70 static int enc_new(BIO *h);
  71 static int enc_free(BIO *data);
  72 static long enc_callback_ctrl(BIO *h, int cmd, bio_info_cb *fps);
  73 #define ENC_BLOCK_SIZE  (1024*4)
  74 #define BUF_OFFSET      (EVP_MAX_BLOCK_LENGTH*2)
  75
  76 typedef struct enc_struct
  77         {
  78         int buf_len;
  79         int buf_off;
  80         int cont;               /* <= 0 when finished */
  81         int finished;
  82         int ok;                 /* bad decrypt */
  83         EVP_CIPHER_CTX cipher;
  84         /* buf is larger than ENC_BLOCK_SIZE because EVP_DecryptUpdate
  85          * can return up to a block more data than is presented to it
  86          */
  87         char buf[ENC_BLOCK_SIZE+BUF_OFFSET+2];
  88         } BIO_ENC_CTX;
  89
  90 static BIO_METHOD methods_enc=
  91         {
  92         BIO_TYPE_CIPHER,"cipher",
  93         enc_write,
  94         enc_read,
  95         NULL, /* enc_puts, */
  96         NULL, /* enc_gets, */
  97         enc_ctrl,
  98         enc_new,
  99         enc_free,
 100         enc_callback_ctrl,
 101         };
 102
 103 BIO_METHOD *BIO_f_cipher(void)
 104         {
 105         return(&methods_enc);
 106         }
 107
 108 static int enc_new(BIO *bi)
 109         {
 110         BIO_ENC_CTX *ctx;
 111
 112         ctx=(BIO_ENC_CTX *)OPENSSL_malloc(sizeof(BIO_ENC_CTX));
 113         if (ctx == NULL) return(0);
 114         EVP_CIPHER_CTX_init(&ctx->cipher);
 115
 116         ctx->buf_len=0;
 117         ctx->buf_off=0;
 118         ctx->cont=1;
 119         ctx->finished=0;
 120         ctx->ok=1;
 121
 122         bi->init=0;
 123         bi->ptr=(char *)ctx;
 124         bi->flags=0;
 125         return(1);
 126         }
 127
 128 static int enc_free(BIO *a)
 129         {
 130         BIO_ENC_CTX *b;
 131
 132         if (a == NULL) return(0);
 133         b=(BIO_ENC_CTX *)a->ptr;
 134         EVP_CIPHER_CTX_cleanup(&(b->cipher));
 135         OPENSSL_cleanse(a->ptr,sizeof(BIO_ENC_CTX));
 136         OPENSSL_free(a->ptr);
 137         a->ptr=NULL;
 138         a->init=0;
 139         a->flags=0;
 140         return(1);
 141         }
 142
 143 static int enc_read(BIO *b, char *out, int outl)
 144         {
 145         int ret=0,i;
 146         BIO_ENC_CTX *ctx;
 147
 148         if (out == NULL) return(0);
 149         ctx=(BIO_ENC_CTX *)b->ptr;
 150
 151         if ((ctx == NULL) || (b->next_bio == NULL)) return(0);
 152
 153         /* First check if there are bytes decoded/encoded */
 154         if (ctx->buf_len > 0)
 155                 {
 156                 i=ctx->buf_len-ctx->buf_off;
 157                 if (i > outl) i=outl;
 158                 memcpy(out,&(ctx->buf[ctx->buf_off]),i);
 159                 ret=i;
 160                 out+=i;
 161                 outl-=i;
 162                 ctx->buf_off+=i;
 163                 if (ctx->buf_len == ctx->buf_off)
 164                         {
 165                         ctx->buf_len=0;
 166                         ctx->buf_off=0;
 167                         }
 168                 }
 169
 170         /* At this point, we have room of outl bytes and an empty
 171          * buffer, so we should read in some more. */
 172
 173         while (outl > 0)
 174                 {
 175                 if (ctx->cont <= 0) break;
 176
 177                 /* read in at IV offset, read the EVP_Cipher
 178                  * documentation about why */
 179                 i=BIO_read(b->next_bio,&(ctx->buf[BUF_OFFSET]),ENC_BLOCK_SIZE);
 180
 181                 if (i <= 0)
 182                         {
 183                         /* Should be continue next time we are called? */
 184                         if (!BIO_should_retry(b->next_bio))
 185                                 {
 186                                 ctx->cont=i;
 187                                 i=EVP_CipherFinal_ex(&(ctx->cipher),
 188                                         (unsigned char *)ctx->buf,
 189                                         &(ctx->buf_len));
 190                                 ctx->ok=i;
 191                                 ctx->buf_off=0;
 192                                 }
 193                         else
 194                                 {
 195                                 ret=(ret == 0)?i:ret;
 196                                 break;
 197                                 }
 198                         }
 199                 else
 200                         {
 201                         EVP_CipherUpdate(&(ctx->cipher),
 202                                 (unsigned char *)ctx->buf,&ctx->buf_len,
 203                                 (unsigned char *)&(ctx->buf[BUF_OFFSET]),i);
 204                         ctx->cont=1;
 205                         /* Note: it is possible for EVP_CipherUpdate to
 206                          * decrypt zero bytes because this is or looks like
 207                          * the final block: if this happens we should retry
 208                          * and either read more data or decrypt the final
 209                          * block
 210                          */
 211                         if(ctx->buf_len == 0) continue;
 212                         }
 213
 214                 if (ctx->buf_len <= outl)
 215                         i=ctx->buf_len;
 216                 else
 217                         i=outl;
 218                 if (i <= 0) break;
 219                 memcpy(out,ctx->buf,i);
 220                 ret+=i;
 221                 ctx->buf_off=i;
 222                 outl-=i;
 223                 out+=i;
 224                 }
 225
 226         BIO_clear_retry_flags(b);
 227         BIO_copy_next_retry(b);
 228         return((ret == 0)?ctx->cont:ret);
 229         }
 230
 231 static int enc_write(BIO *b, const char *in, int inl)
 232         {
 233         int ret=0,n,i;
 234         BIO_ENC_CTX *ctx;
 235
 236         ctx=(BIO_ENC_CTX *)b->ptr;
 237         ret=inl;
 238
 239         BIO_clear_retry_flags(b);
 240         n=ctx->buf_len-ctx->buf_off;
 241         while (n > 0)
 242                 {
 243                 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
 244                 if (i <= 0)
 245                         {
 246                         BIO_copy_next_retry(b);
 247                         return(i);
 248                         }
 249                 ctx->buf_off+=i;
 250                 n-=i;
 251                 }
 252         /* at this point all pending data has been written */
 253
 254         if ((in == NULL) || (inl <= 0)) return(0);
 255
 256         ctx->buf_off=0;
 257         while (inl > 0)
 258                 {
 259                 n=(inl > ENC_BLOCK_SIZE)?ENC_BLOCK_SIZE:inl;
 260                 EVP_CipherUpdate(&(ctx->cipher),
 261                         (unsigned char *)ctx->buf,&ctx->buf_len,
 262                         (unsigned char *)in,n);
 263                 inl-=n;
 264                 in+=n;
 265
 266                 ctx->buf_off=0;
 267                 n=ctx->buf_len;
 268                 while (n > 0)
 269                         {
 270                         i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
 271                         if (i <= 0)
 272                                 {
 273                                 BIO_copy_next_retry(b);
 274                                 return (ret == inl) ? i : ret - inl;
 275                                 }
 276                         n-=i;
 277                         ctx->buf_off+=i;
 278                         }
 279                 ctx->buf_len=0;
 280                 ctx->buf_off=0;
 281                 }
 282         BIO_copy_next_retry(b);
 283         return(ret);
 284         }
 285
 286 static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)
 287         {
 288         BIO *dbio;
 289         BIO_ENC_CTX *ctx,*dctx;
 290         long ret=1;
 291         int i;
 292         EVP_CIPHER_CTX **c_ctx;
 293
 294         ctx=(BIO_ENC_CTX *)b->ptr;
 295
 296         switch (cmd)
 297                 {
 298         case BIO_CTRL_RESET:
 299                 ctx->ok=1;
 300                 ctx->finished=0;
 301                 EVP_CipherInit_ex(&(ctx->cipher),NULL,NULL,NULL,NULL,
 302                         ctx->cipher.encrypt);
 303                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
 304                 break;
 305         case BIO_CTRL_EOF:      /* More to read */
 306                 if (ctx->cont <= 0)
 307                         ret=1;
 308                 else
 309                         ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
 310                 break;
 311         case BIO_CTRL_WPENDING:
 312                 ret=ctx->buf_len-ctx->buf_off;
 313                 if (ret <= 0)
 314                         ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
 315                 break;
 316         case BIO_CTRL_PENDING: /* More to read in buffer */
 317                 ret=ctx->buf_len-ctx->buf_off;
 318                 if (ret <= 0)
 319                         ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
 320                 break;
 321         case BIO_CTRL_FLUSH:
 322                 /* do a final write */
 323 again:
 324                 while (ctx->buf_len != ctx->buf_off)
 325                         {
 326                         i=enc_write(b,NULL,0);
 327                         if (i < 0)
 328                                 return i;
 329                         }
 330
 331                 if (!ctx->finished)
 332                         {
 333                         ctx->finished=1;
 334                         ctx->buf_off=0;
 335                         ret=EVP_CipherFinal_ex(&(ctx->cipher),
 336                                 (unsigned char *)ctx->buf,
 337                                 &(ctx->buf_len));
 338                         ctx->ok=(int)ret;
 339                         if (ret <= 0) break;
 340
 341                         /* push out the bytes */
 342                         goto again;
 343                         }
 344
 345                 /* Finally flush the underlying BIO */
 346                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
 347                 break;
 348         case BIO_C_GET_CIPHER_STATUS:
 349                 ret=(long)ctx->ok;
 350                 break;
 351         case BIO_C_DO_STATE_MACHINE:
 352                 BIO_clear_retry_flags(b);
 353                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
 354                 BIO_copy_next_retry(b);
 355                 break;
 356         case BIO_C_GET_CIPHER_CTX:
 357                 c_ctx=(EVP_CIPHER_CTX **)ptr;
 358                 (*c_ctx)= &(ctx->cipher);
 359                 b->init=1;
 360                 break;
 361         case BIO_CTRL_DUP:
 362                 dbio=(BIO *)ptr;
 363                 dctx=(BIO_ENC_CTX *)dbio->ptr;
 364                 memcpy(&(dctx->cipher),&(ctx->cipher),sizeof(ctx->cipher));
 365                 dbio->init=1;
 366                 break;
 367         default:
 368                 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
 369                 break;
 370                 }
 371         return(ret);
 372         }
 373
 374 static long enc_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
 375         {
 376         long ret=1;
 377
 378         if (b->next_bio == NULL) return(0);
 379         switch (cmd)
 380                 {
 381         default:
 382                 ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
 383                 break;
 384                 }
 385         return(ret);
 386         }
 387
 388 /*
 389 void BIO_set_cipher_ctx(b,c)
 390 BIO *b;
 391 EVP_CIPHER_ctx *c;
 392         {
 393         if (b == NULL) return;
 394
 395         if ((b->callback != NULL) &&
 396                 (b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))
 397                 return;
 398
 399         b->init=1;
 400         ctx=(BIO_ENC_CTX *)b->ptr;
 401         memcpy(ctx->cipher,c,sizeof(EVP_CIPHER_CTX));
 402
 403         if (b->callback != NULL)
 404                 b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);
 405         }
 406 */
 407
 408 void BIO_set_cipher(BIO *b, const EVP_CIPHER *c, const unsigned char *k,
 409              const unsigned char *i, int e)
 410         {
 411         BIO_ENC_CTX *ctx;
 412
 413         if (b == NULL) return;
 414
 415         if ((b->callback != NULL) &&
 416                 (b->callback(b,BIO_CB_CTRL,(const char *)c,BIO_CTRL_SET,e,0L) <= 0))
 417                 return;
 418
 419         b->init=1;
 420         ctx=(BIO_ENC_CTX *)b->ptr;
 421         EVP_CipherInit_ex(&(ctx->cipher),c,NULL, k,i,e);
 422
 423         if (b->callback != NULL)
 424                 b->callback(b,BIO_CB_CTRL,(const char *)c,BIO_CTRL_SET,e,1L);
 425         }
 426