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 8 /* XXX: why? */
76 typedef struct enc_struct
80 int cont; /* <= 0 when finished */
82 int ok; /* bad decrypt */
83 EVP_CIPHER_CTX cipher;
84 char buf[ENC_BLOCK_SIZE+BUF_OFFSET+2/*why?*/];
87 static BIO_METHOD methods_enc=
89 BIO_TYPE_CIPHER,"cipher",
100 BIO_METHOD *BIO_f_cipher(void)
102 return(&methods_enc);
105 static int enc_new(BIO *bi)
109 ctx=(BIO_ENC_CTX *)OPENSSL_malloc(sizeof(BIO_ENC_CTX));
110 EVP_CIPHER_CTX_init(&ctx->cipher);
111 if (ctx == NULL) return(0);
125 static int enc_free(BIO *a)
129 if (a == NULL) return(0);
130 b=(BIO_ENC_CTX *)a->ptr;
131 EVP_CIPHER_CTX_cleanup(&(b->cipher));
132 memset(a->ptr,0,sizeof(BIO_ENC_CTX));
133 OPENSSL_free(a->ptr);
140 static int enc_read(BIO *b, char *out, int outl)
145 if (out == NULL) return(0);
146 ctx=(BIO_ENC_CTX *)b->ptr;
148 if ((ctx == NULL) || (b->next_bio == NULL)) return(0);
150 /* First check if there are bytes decoded/encoded */
151 if (ctx->buf_len > 0)
153 i=ctx->buf_len-ctx->buf_off;
154 if (i > outl) i=outl;
155 memcpy(out,&(ctx->buf[ctx->buf_off]),i);
160 if (ctx->buf_len == ctx->buf_off)
167 /* At this point, we have room of outl bytes and an empty
168 * buffer, so we should read in some more. */
172 if (ctx->cont <= 0) break;
174 /* read in at offset 8, read the EVP_Cipher
175 * documentation about why */
176 i=BIO_read(b->next_bio,&(ctx->buf[BUF_OFFSET]),ENC_BLOCK_SIZE);
180 /* Should be continue next time we are called? */
181 if (!BIO_should_retry(b->next_bio))
184 i=EVP_CipherFinal(&(ctx->cipher),
185 (unsigned char *)ctx->buf,
192 ret=(ret == 0)?i:ret;
198 EVP_CipherUpdate(&(ctx->cipher),
199 (unsigned char *)ctx->buf,&ctx->buf_len,
200 (unsigned char *)&(ctx->buf[BUF_OFFSET]),i);
202 /* Note: it is possible for EVP_CipherUpdate to
203 * decrypt zero bytes because this is or looks like
204 * the final block: if this happens we should retry
205 * and either read more data or decrypt the final
208 if(ctx->buf_len == 0) continue;
211 if (ctx->buf_len <= outl)
216 memcpy(out,ctx->buf,i);
223 BIO_clear_retry_flags(b);
224 BIO_copy_next_retry(b);
225 return((ret == 0)?ctx->cont:ret);
228 static int enc_write(BIO *b, const char *in, int inl)
233 ctx=(BIO_ENC_CTX *)b->ptr;
236 BIO_clear_retry_flags(b);
237 n=ctx->buf_len-ctx->buf_off;
240 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
243 BIO_copy_next_retry(b);
249 /* at this point all pending data has been written */
251 if ((in == NULL) || (inl <= 0)) return(0);
256 n=(inl > ENC_BLOCK_SIZE)?ENC_BLOCK_SIZE:inl;
257 EVP_CipherUpdate(&(ctx->cipher),
258 (unsigned char *)ctx->buf,&ctx->buf_len,
259 (unsigned char *)in,n);
267 i=BIO_write(b->next_bio,&(ctx->buf[ctx->buf_off]),n);
270 BIO_copy_next_retry(b);
279 BIO_copy_next_retry(b);
283 static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)
286 BIO_ENC_CTX *ctx,*dctx;
289 EVP_CIPHER_CTX **c_ctx;
291 ctx=(BIO_ENC_CTX *)b->ptr;
298 EVP_CipherInit(&(ctx->cipher),NULL,NULL,NULL,
299 ctx->cipher.encrypt);
300 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
302 case BIO_CTRL_EOF: /* More to read */
306 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
308 case BIO_CTRL_WPENDING:
309 ret=ctx->buf_len-ctx->buf_off;
311 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
313 case BIO_CTRL_PENDING: /* More to read in buffer */
314 ret=ctx->buf_len-ctx->buf_off;
316 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
319 /* do a final write */
321 while (ctx->buf_len != ctx->buf_off)
323 i=enc_write(b,NULL,0);
335 ret=EVP_CipherFinal(&(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 memcpy(&(dctx->cipher),&(ctx->cipher),sizeof(ctx->cipher));
368 ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
374 static long enc_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
378 if (b->next_bio == NULL) return(0);
382 ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
389 void BIO_set_cipher_ctx(b,c)
393 if (b == NULL) return;
395 if ((b->callback != NULL) &&
396 (b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))
400 ctx=(BIO_ENC_CTX *)b->ptr;
401 memcpy(ctx->cipher,c,sizeof(EVP_CIPHER_CTX));
403 if (b->callback != NULL)
404 b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);
408 void BIO_set_cipher(BIO *b, const EVP_CIPHER *c, unsigned char *k,
409 unsigned char *i, int e)
413 if (b == NULL) return;
415 if ((b->callback != NULL) &&
416 (b->callback(b,BIO_CB_CTRL,(const char *)c,BIO_CTRL_SET,e,0L) <= 0))
420 ctx=(BIO_ENC_CTX *)b->ptr;
421 EVP_CipherInit(&(ctx->cipher),c,k,i,e);
423 if (b->callback != NULL)
424 b->callback(b,BIO_CB_CTRL,(const char *)c,BIO_CTRL_SET,e,1L);