1 /* Copyright (C) 1995-1998 Eric Young (eay@cryptsoft.com)
4 * This package is an SSL implementation written
5 * by Eric Young (eay@cryptsoft.com).
6 * The implementation was written so as to conform with Netscapes SSL.
8 * This library is free for commercial and non-commercial use as long as
9 * the following conditions are aheared to. The following conditions
10 * apply to all code found in this distribution, be it the RC4, RSA,
11 * lhash, DES, etc., code; not just the SSL code. The SSL documentation
12 * included with this distribution is covered by the same copyright terms
13 * except that the holder is Tim Hudson (tjh@cryptsoft.com).
15 * Copyright remains Eric Young's, and as such any Copyright notices in
16 * the code are not to be removed.
17 * If this package is used in a product, Eric Young should be given attribution
18 * as the author of the parts of the library used.
19 * This can be in the form of a textual message at program startup or
20 * in documentation (online or textual) provided with the package.
22 * Redistribution and use in source and binary forms, with or without
23 * modification, are permitted provided that the following conditions
25 * 1. Redistributions of source code must retain the copyright
26 * notice, this list of conditions and the following disclaimer.
27 * 2. Redistributions in binary form must reproduce the above copyright
28 * notice, this list of conditions and the following disclaimer in the
29 * documentation and/or other materials provided with the distribution.
30 * 3. All advertising materials mentioning features or use of this software
31 * must display the following acknowledgement:
32 * "This product includes cryptographic software written by
33 * Eric Young (eay@cryptsoft.com)"
34 * The word 'cryptographic' can be left out if the rouines from the library
35 * being used are not cryptographic related :-).
36 * 4. If you include any Windows specific code (or a derivative thereof) from
37 * the apps directory (application code) you must include an acknowledgement:
38 * "This product includes software written by Tim Hudson (tjh@cryptsoft.com)"
40 * THIS SOFTWARE IS PROVIDED BY ERIC YOUNG ``AS IS'' AND
41 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
42 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
43 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
44 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
45 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
46 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
47 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
48 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
49 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
52 * The licence and distribution terms for any publically available version or
53 * derivative of this code cannot be changed. i.e. this code cannot simply be
54 * copied and put under another distribution licence
55 * [including the GNU Public Licence.]
60 #include "internal/cryptlib.h"
61 #include <openssl/buffer.h>
62 #include <openssl/evp.h>
63 #include "internal/bio.h"
65 static int enc_write(BIO *h, const char *buf, int num);
66 static int enc_read(BIO *h, char *buf, int size);
68 * static int enc_puts(BIO *h, const char *str);
71 * static int enc_gets(BIO *h, char *str, int size);
73 static long enc_ctrl(BIO *h, int cmd, long arg1, void *arg2);
74 static int enc_new(BIO *h);
75 static int enc_free(BIO *data);
76 static long enc_callback_ctrl(BIO *h, int cmd, bio_info_cb *fps);
77 #define ENC_BLOCK_SIZE (1024*4)
78 #define BUF_OFFSET (EVP_MAX_BLOCK_LENGTH*2)
80 typedef struct enc_struct {
83 int cont; /* <= 0 when finished */
85 int ok; /* bad decrypt */
86 EVP_CIPHER_CTX *cipher;
88 * buf is larger than ENC_BLOCK_SIZE because EVP_DecryptUpdate can return
89 * up to a block more data than is presented to it
91 char buf[ENC_BLOCK_SIZE + BUF_OFFSET + 2];
94 static const BIO_METHOD methods_enc = {
95 BIO_TYPE_CIPHER, "cipher",
106 const BIO_METHOD *BIO_f_cipher(void)
108 return (&methods_enc);
111 static int enc_new(BIO *bi)
115 ctx = OPENSSL_zalloc(sizeof(*ctx));
119 ctx->cipher = EVP_CIPHER_CTX_new();
120 if (ctx->cipher == NULL) {
126 BIO_set_data(bi, ctx);
132 static int enc_free(BIO *a)
143 EVP_CIPHER_CTX_free(b->cipher);
144 OPENSSL_clear_free(b, sizeof(BIO_ENC_CTX));
145 BIO_set_data(a, NULL);
151 static int enc_read(BIO *b, char *out, int outl)
159 ctx = BIO_get_data(b);
162 if ((ctx == NULL) || (next == NULL))
165 /* First check if there are bytes decoded/encoded */
166 if (ctx->buf_len > 0) {
167 i = ctx->buf_len - ctx->buf_off;
170 memcpy(out, &(ctx->buf[ctx->buf_off]), i);
175 if (ctx->buf_len == ctx->buf_off) {
182 * At this point, we have room of outl bytes and an empty buffer, so we
183 * should read in some more.
191 * read in at IV offset, read the EVP_Cipher documentation about why
193 i = BIO_read(next, &(ctx->buf[BUF_OFFSET]), ENC_BLOCK_SIZE);
196 /* Should be continue next time we are called? */
197 if (!BIO_should_retry(next)) {
199 i = EVP_CipherFinal_ex(ctx->cipher,
200 (unsigned char *)ctx->buf,
205 ret = (ret == 0) ? i : ret;
209 if (!EVP_CipherUpdate(ctx->cipher,
210 (unsigned char *)ctx->buf, &ctx->buf_len,
211 (unsigned char *)&(ctx->buf[BUF_OFFSET]),
213 BIO_clear_retry_flags(b);
218 * Note: it is possible for EVP_CipherUpdate to decrypt zero
219 * bytes because this is or looks like the final block: if this
220 * happens we should retry and either read more data or decrypt
223 if (ctx->buf_len == 0)
227 if (ctx->buf_len <= outl)
233 memcpy(out, ctx->buf, i);
240 BIO_clear_retry_flags(b);
241 BIO_copy_next_retry(b);
242 return ((ret == 0) ? ctx->cont : ret);
245 static int enc_write(BIO *b, const char *in, int inl)
251 ctx = BIO_get_data(b);
253 if ((ctx == NULL) || (next == NULL))
258 BIO_clear_retry_flags(b);
259 n = ctx->buf_len - ctx->buf_off;
261 i = BIO_write(next, &(ctx->buf[ctx->buf_off]), n);
263 BIO_copy_next_retry(b);
269 /* at this point all pending data has been written */
271 if ((in == NULL) || (inl <= 0))
276 n = (inl > ENC_BLOCK_SIZE) ? ENC_BLOCK_SIZE : inl;
277 if (!EVP_CipherUpdate(ctx->cipher,
278 (unsigned char *)ctx->buf, &ctx->buf_len,
279 (unsigned char *)in, n)) {
280 BIO_clear_retry_flags(b);
289 i = BIO_write(next, &(ctx->buf[ctx->buf_off]), n);
291 BIO_copy_next_retry(b);
292 return (ret == inl) ? i : ret - inl;
300 BIO_copy_next_retry(b);
304 static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)
307 BIO_ENC_CTX *ctx, *dctx;
310 EVP_CIPHER_CTX **c_ctx;
313 ctx = BIO_get_data(b);
322 if (!EVP_CipherInit_ex(ctx->cipher, NULL, NULL, NULL, NULL,
323 EVP_CIPHER_CTX_encrypting(ctx->cipher)))
325 ret = BIO_ctrl(next, cmd, num, ptr);
327 case BIO_CTRL_EOF: /* More to read */
331 ret = BIO_ctrl(next, cmd, num, ptr);
333 case BIO_CTRL_WPENDING:
334 ret = ctx->buf_len - ctx->buf_off;
336 ret = BIO_ctrl(next, cmd, num, ptr);
338 case BIO_CTRL_PENDING: /* More to read in buffer */
339 ret = ctx->buf_len - ctx->buf_off;
341 ret = BIO_ctrl(next, cmd, num, ptr);
344 /* do a final write */
346 while (ctx->buf_len != ctx->buf_off) {
347 i = enc_write(b, NULL, 0);
352 if (!ctx->finished) {
355 ret = EVP_CipherFinal_ex(ctx->cipher,
356 (unsigned char *)ctx->buf,
362 /* push out the bytes */
366 /* Finally flush the underlying BIO */
367 ret = BIO_ctrl(next, cmd, num, ptr);
369 case BIO_C_GET_CIPHER_STATUS:
372 case BIO_C_DO_STATE_MACHINE:
373 BIO_clear_retry_flags(b);
374 ret = BIO_ctrl(next, cmd, num, ptr);
375 BIO_copy_next_retry(b);
377 case BIO_C_GET_CIPHER_CTX:
378 c_ctx = (EVP_CIPHER_CTX **)ptr;
379 *c_ctx = ctx->cipher;
384 dctx = BIO_get_data(dbio);
385 dctx->cipher = EVP_CIPHER_CTX_new();
386 if (dctx->cipher == NULL)
388 ret = EVP_CIPHER_CTX_copy(dctx->cipher, ctx->cipher);
390 BIO_set_init(dbio, 1);
393 ret = BIO_ctrl(next, cmd, num, ptr);
399 static long enc_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
402 BIO *next = BIO_next(b);
408 ret = BIO_callback_ctrl(next, cmd, fp);
415 void BIO_set_cipher_ctx(b,c)
419 if (b == NULL) return;
421 if ((b->callback != NULL) &&
422 (b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))
426 ctx=(BIO_ENC_CTX *)b->ptr;
427 memcpy(ctx->cipher,c,sizeof(EVP_CIPHER_CTX));
429 if (b->callback != NULL)
430 b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);
434 int BIO_set_cipher(BIO *b, const EVP_CIPHER *c, const unsigned char *k,
435 const unsigned char *i, int e)
438 long (*callback) (struct bio_st *, int, const char *, int, long, long);
440 ctx = BIO_get_data(b);
444 callback = BIO_get_callback(b);
446 if ((callback != NULL) &&
447 (callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e,
453 if (!EVP_CipherInit_ex(ctx->cipher, c, NULL, k, i, e))
456 if (callback != NULL)
457 return callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e, 1L);