1 /* crypto/evp/bio_enc.c */
2 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
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.
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).
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.
23 * Redistribution and use in source and binary forms, with or without
24 * modification, are permitted provided that the following conditions
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)"
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
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.]
62 #include <openssl/buffer.h>
63 #include <openssl/evp.h>
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)
76 typedef struct enc_struct
80 int cont
; /* <= 0 when 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
87 char buf
[ENC_BLOCK_SIZE
+BUF_OFFSET
+2];
90 static BIO_METHOD methods_enc
=
92 BIO_TYPE_CIPHER
,"cipher",
103 BIO_METHOD
*BIO_f_cipher(void)
105 return(&methods_enc
);
108 static int enc_new(BIO
*bi
)
112 ctx
=(BIO_ENC_CTX
*)OPENSSL_malloc(sizeof(BIO_ENC_CTX
));
113 if (ctx
== NULL
) return(0);
114 EVP_CIPHER_CTX_init(&ctx
->cipher
);
128 static int enc_free(BIO
*a
)
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
);
143 static int enc_read(BIO
*b
, char *out
, int outl
)
148 if (out
== NULL
) return(0);
149 ctx
=(BIO_ENC_CTX
*)b
->ptr
;
151 if ((ctx
== NULL
) || (b
->next_bio
== NULL
)) return(0);
153 /* First check if there are bytes decoded/encoded */
154 if (ctx
->buf_len
> 0)
156 i
=ctx
->buf_len
-ctx
->buf_off
;
157 if (i
> outl
) i
=outl
;
158 memcpy(out
,&(ctx
->buf
[ctx
->buf_off
]),i
);
163 if (ctx
->buf_len
== ctx
->buf_off
)
170 /* At this point, we have room of outl bytes and an empty
171 * buffer, so we should read in some more. */
175 if (ctx
->cont
<= 0) break;
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
);
183 /* Should be continue next time we are called? */
184 if (!BIO_should_retry(b
->next_bio
))
187 i
=EVP_CipherFinal_ex(&(ctx
->cipher
),
188 (unsigned char *)ctx
->buf
,
195 ret
=(ret
== 0)?i
:ret
;
201 EVP_CipherUpdate(&(ctx
->cipher
),
202 (unsigned char *)ctx
->buf
,&ctx
->buf_len
,
203 (unsigned char *)&(ctx
->buf
[BUF_OFFSET
]),i
);
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
211 if(ctx
->buf_len
== 0) continue;
214 if (ctx
->buf_len
<= outl
)
219 memcpy(out
,ctx
->buf
,i
);
226 BIO_clear_retry_flags(b
);
227 BIO_copy_next_retry(b
);
228 return((ret
== 0)?ctx
->cont
:ret
);
231 static int enc_write(BIO
*b
, const char *in
, int inl
)
236 ctx
=(BIO_ENC_CTX
*)b
->ptr
;
239 BIO_clear_retry_flags(b
);
240 n
=ctx
->buf_len
-ctx
->buf_off
;
243 i
=BIO_write(b
->next_bio
,&(ctx
->buf
[ctx
->buf_off
]),n
);
246 BIO_copy_next_retry(b
);
252 /* at this point all pending data has been written */
254 if ((in
== NULL
) || (inl
<= 0)) return(0);
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
);
270 i
=BIO_write(b
->next_bio
,&(ctx
->buf
[ctx
->buf_off
]),n
);
273 BIO_copy_next_retry(b
);
274 return (ret
== inl
) ? i
: ret
- inl
;
282 BIO_copy_next_retry(b
);
286 static long enc_ctrl(BIO
*b
, int cmd
, long num
, void *ptr
)
289 BIO_ENC_CTX
*ctx
,*dctx
;
292 EVP_CIPHER_CTX
**c_ctx
;
294 ctx
=(BIO_ENC_CTX
*)b
->ptr
;
301 EVP_CipherInit_ex(&(ctx
->cipher
),NULL
,NULL
,NULL
,NULL
,
302 ctx
->cipher
.encrypt
);
303 ret
=BIO_ctrl(b
->next_bio
,cmd
,num
,ptr
);
305 case BIO_CTRL_EOF
: /* More to read */
309 ret
=BIO_ctrl(b
->next_bio
,cmd
,num
,ptr
);
311 case BIO_CTRL_WPENDING
:
312 ret
=ctx
->buf_len
-ctx
->buf_off
;
314 ret
=BIO_ctrl(b
->next_bio
,cmd
,num
,ptr
);
316 case BIO_CTRL_PENDING
: /* More to read in buffer */
317 ret
=ctx
->buf_len
-ctx
->buf_off
;
319 ret
=BIO_ctrl(b
->next_bio
,cmd
,num
,ptr
);
322 /* do a final write */
324 while (ctx
->buf_len
!= ctx
->buf_off
)
326 i
=enc_write(b
,NULL
,0);
335 ret
=EVP_CipherFinal_ex(&(ctx
->cipher
),
336 (unsigned char *)ctx
->buf
,
341 /* push out the bytes */
345 /* Finally flush the underlying BIO */
346 ret
=BIO_ctrl(b
->next_bio
,cmd
,num
,ptr
);
348 case BIO_C_GET_CIPHER_STATUS
:
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
);
356 case BIO_C_GET_CIPHER_CTX
:
357 c_ctx
=(EVP_CIPHER_CTX
**)ptr
;
358 (*c_ctx
)= &(ctx
->cipher
);
363 dctx
=(BIO_ENC_CTX
*)dbio
->ptr
;
364 EVP_CIPHER_CTX_init(&dctx
->cipher
);
365 ret
= EVP_CIPHER_CTX_copy(&dctx
->cipher
,&ctx
->cipher
);
370 ret
=BIO_ctrl(b
->next_bio
,cmd
,num
,ptr
);
376 static long enc_callback_ctrl(BIO
*b
, int cmd
, bio_info_cb
*fp
)
380 if (b
->next_bio
== NULL
) return(0);
384 ret
=BIO_callback_ctrl(b
->next_bio
,cmd
,fp
);
391 void BIO_set_cipher_ctx(b,c)
395 if (b == NULL) return;
397 if ((b->callback != NULL) &&
398 (b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))
402 ctx=(BIO_ENC_CTX *)b->ptr;
403 memcpy(ctx->cipher,c,sizeof(EVP_CIPHER_CTX));
405 if (b->callback != NULL)
406 b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);
410 void BIO_set_cipher(BIO
*b
, const EVP_CIPHER
*c
, const unsigned char *k
,
411 const unsigned char *i
, int e
)
415 if (b
== NULL
) return;
417 if ((b
->callback
!= NULL
) &&
418 (b
->callback(b
,BIO_CB_CTRL
,(const char *)c
,BIO_CTRL_SET
,e
,0L) <= 0))
422 ctx
=(BIO_ENC_CTX
*)b
->ptr
;
423 EVP_CipherInit_ex(&(ctx
->cipher
),c
,NULL
, k
,i
,e
);
425 if (b
->callback
!= NULL
)
426 b
->callback(b
,BIO_CB_CTRL
,(const char *)c
,BIO_CTRL_SET
,e
,1L);