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>
64 static int enc_write(BIO *h, const char *buf, int num);
65 static int enc_read(BIO *h, char *buf, int size);
67 * static int enc_puts(BIO *h, const char *str);
70 * static int enc_gets(BIO *h, char *str, int size);
72 static long enc_ctrl(BIO *h, int cmd, long arg1, void *arg2);
73 static int enc_new(BIO *h);
74 static int enc_free(BIO *data);
75 static long enc_callback_ctrl(BIO *h, int cmd, bio_info_cb *fps);
76 #define ENC_BLOCK_SIZE (1024*4)
77 #define BUF_OFFSET (EVP_MAX_BLOCK_LENGTH*2)
79 typedef struct enc_struct {
82 int cont; /* <= 0 when finished */
84 int ok; /* bad decrypt */
85 EVP_CIPHER_CTX *cipher;
87 * buf is larger than ENC_BLOCK_SIZE because EVP_DecryptUpdate can return
88 * up to a block more data than is presented to it
90 char buf[ENC_BLOCK_SIZE + BUF_OFFSET + 2];
93 static const BIO_METHOD methods_enc = {
94 BIO_TYPE_CIPHER, "cipher",
105 const BIO_METHOD *BIO_f_cipher(void)
107 return (&methods_enc);
110 static int enc_new(BIO *bi)
114 ctx = OPENSSL_zalloc(sizeof(*ctx));
118 ctx->cipher = EVP_CIPHER_CTX_new();
119 if (ctx->cipher == NULL) {
126 bi->ptr = (char *)ctx;
131 static int enc_free(BIO *a)
137 b = (BIO_ENC_CTX *)a->ptr;
138 EVP_CIPHER_CTX_free(b->cipher);
139 OPENSSL_clear_free(a->ptr, sizeof(BIO_ENC_CTX));
146 static int enc_read(BIO *b, char *out, int outl)
153 ctx = (BIO_ENC_CTX *)b->ptr;
155 if ((ctx == NULL) || (b->next_bio == NULL))
158 /* First check if there are bytes decoded/encoded */
159 if (ctx->buf_len > 0) {
160 i = ctx->buf_len - ctx->buf_off;
163 memcpy(out, &(ctx->buf[ctx->buf_off]), i);
168 if (ctx->buf_len == ctx->buf_off) {
175 * At this point, we have room of outl bytes and an empty buffer, so we
176 * should read in some more.
184 * read in at IV offset, read the EVP_Cipher documentation about why
186 i = BIO_read(b->next_bio, &(ctx->buf[BUF_OFFSET]), ENC_BLOCK_SIZE);
189 /* Should be continue next time we are called? */
190 if (!BIO_should_retry(b->next_bio)) {
192 i = EVP_CipherFinal_ex(ctx->cipher,
193 (unsigned char *)ctx->buf,
198 ret = (ret == 0) ? i : ret;
202 if (!EVP_CipherUpdate(ctx->cipher,
203 (unsigned char *)ctx->buf, &ctx->buf_len,
204 (unsigned char *)&(ctx->buf[BUF_OFFSET]),
206 BIO_clear_retry_flags(b);
211 * Note: it is possible for EVP_CipherUpdate to decrypt zero
212 * bytes because this is or looks like the final block: if this
213 * happens we should retry and either read more data or decrypt
216 if (ctx->buf_len == 0)
220 if (ctx->buf_len <= outl)
226 memcpy(out, ctx->buf, i);
233 BIO_clear_retry_flags(b);
234 BIO_copy_next_retry(b);
235 return ((ret == 0) ? ctx->cont : ret);
238 static int enc_write(BIO *b, const char *in, int inl)
243 ctx = (BIO_ENC_CTX *)b->ptr;
246 BIO_clear_retry_flags(b);
247 n = ctx->buf_len - ctx->buf_off;
249 i = BIO_write(b->next_bio, &(ctx->buf[ctx->buf_off]), n);
251 BIO_copy_next_retry(b);
257 /* at this point all pending data has been written */
259 if ((in == NULL) || (inl <= 0))
264 n = (inl > ENC_BLOCK_SIZE) ? ENC_BLOCK_SIZE : inl;
265 if (!EVP_CipherUpdate(ctx->cipher,
266 (unsigned char *)ctx->buf, &ctx->buf_len,
267 (unsigned char *)in, n)) {
268 BIO_clear_retry_flags(b);
277 i = BIO_write(b->next_bio, &(ctx->buf[ctx->buf_off]), n);
279 BIO_copy_next_retry(b);
280 return (ret == inl) ? i : ret - inl;
288 BIO_copy_next_retry(b);
292 static long enc_ctrl(BIO *b, int cmd, long num, void *ptr)
295 BIO_ENC_CTX *ctx, *dctx;
298 EVP_CIPHER_CTX **c_ctx;
300 ctx = (BIO_ENC_CTX *)b->ptr;
306 if (!EVP_CipherInit_ex(ctx->cipher, NULL, NULL, NULL, NULL,
307 EVP_CIPHER_CTX_encrypting(ctx->cipher)))
309 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
311 case BIO_CTRL_EOF: /* More to read */
315 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
317 case BIO_CTRL_WPENDING:
318 ret = ctx->buf_len - ctx->buf_off;
320 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
322 case BIO_CTRL_PENDING: /* More to read in buffer */
323 ret = ctx->buf_len - ctx->buf_off;
325 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
328 /* do a final write */
330 while (ctx->buf_len != ctx->buf_off) {
331 i = enc_write(b, NULL, 0);
336 if (!ctx->finished) {
339 ret = EVP_CipherFinal_ex(ctx->cipher,
340 (unsigned char *)ctx->buf,
346 /* push out the bytes */
350 /* Finally flush the underlying BIO */
351 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
353 case BIO_C_GET_CIPHER_STATUS:
356 case BIO_C_DO_STATE_MACHINE:
357 BIO_clear_retry_flags(b);
358 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
359 BIO_copy_next_retry(b);
361 case BIO_C_GET_CIPHER_CTX:
362 c_ctx = (EVP_CIPHER_CTX **)ptr;
363 *c_ctx = ctx->cipher;
368 dctx = (BIO_ENC_CTX *)dbio->ptr;
369 dctx->cipher = EVP_CIPHER_CTX_new();
370 if (dctx->cipher == NULL)
372 ret = EVP_CIPHER_CTX_copy(dctx->cipher, ctx->cipher);
377 ret = BIO_ctrl(b->next_bio, cmd, num, ptr);
383 static long enc_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
387 if (b->next_bio == NULL)
391 ret = BIO_callback_ctrl(b->next_bio, cmd, fp);
398 void BIO_set_cipher_ctx(b,c)
402 if (b == NULL) return;
404 if ((b->callback != NULL) &&
405 (b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,0L) <= 0))
409 ctx=(BIO_ENC_CTX *)b->ptr;
410 memcpy(ctx->cipher,c,sizeof(EVP_CIPHER_CTX));
412 if (b->callback != NULL)
413 b->callback(b,BIO_CB_CTRL,(char *)c,BIO_CTRL_SET,e,1L);
417 int BIO_set_cipher(BIO *b, const EVP_CIPHER *c, const unsigned char *k,
418 const unsigned char *i, int e)
425 if ((b->callback != NULL) &&
426 (b->callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e, 0L) <=
431 ctx = (BIO_ENC_CTX *)b->ptr;
432 if (!EVP_CipherInit_ex(ctx->cipher, c, NULL, k, i, e))
435 if (b->callback != NULL)
436 return b->callback(b, BIO_CB_CTRL, (const char *)c, BIO_CTRL_SET, e,