1/* crypto/evp/bio_md.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/* BIO_put and BIO_get both add to the digest,
66 * BIO_gets returns the digest */
67
68static int md_write(BIO *h, char const *buf, int num);
69static int md_read(BIO *h, char *buf, int size);
70/*static int md_puts(BIO *h, const char *str); */
71static int md_gets(BIO *h, char *str, int size);
72static long md_ctrl(BIO *h, int cmd, long arg1, void *arg2);
73static int md_new(BIO *h);
74static int md_free(BIO *data);
75static long md_callback_ctrl(BIO *h,int cmd,bio_info_cb *fp);
76
77static BIO_METHOD methods_md=
78	{
79	BIO_TYPE_MD,"message digest",
80	md_write,
81	md_read,
82	NULL, /* md_puts, */
83	md_gets,
84	md_ctrl,
85	md_new,
86	md_free,
87	md_callback_ctrl,
88	};
89
90BIO_METHOD *BIO_f_md(void)
91	{
92	return(&methods_md);
93	}
94
95static int md_new(BIO *bi)
96	{
97	EVP_MD_CTX *ctx;
98
99	ctx=EVP_MD_CTX_create();
100	if (ctx == NULL) return(0);
101
102	bi->init=0;
103	bi->ptr=(char *)ctx;
104	bi->flags=0;
105	return(1);
106	}
107
108static int md_free(BIO *a)
109	{
110	if (a == NULL) return(0);
111	EVP_MD_CTX_destroy(a->ptr);
112	a->ptr=NULL;
113	a->init=0;
114	a->flags=0;
115	return(1);
116	}
117
118static int md_read(BIO *b, char *out, int outl)
119	{
120	int ret=0;
121	EVP_MD_CTX *ctx;
122
123	if (out == NULL) return(0);
124	ctx=b->ptr;
125
126	if ((ctx == NULL) || (b->next_bio == NULL)) return(0);
127
128	ret=BIO_read(b->next_bio,out,outl);
129	if (b->init)
130		{
131		if (ret > 0)
132			{
133			EVP_DigestUpdate(ctx,(unsigned char *)out,
134				(unsigned int)ret);
135			}
136		}
137	BIO_clear_retry_flags(b);
138	BIO_copy_next_retry(b);
139	return(ret);
140	}
141
142static int md_write(BIO *b, const char *in, int inl)
143	{
144	int ret=0;
145	EVP_MD_CTX *ctx;
146
147	if ((in == NULL) || (inl <= 0)) return(0);
148	ctx=b->ptr;
149
150	if ((ctx != NULL) && (b->next_bio != NULL))
151		ret=BIO_write(b->next_bio,in,inl);
152	if (b->init)
153		{
154		if (ret > 0)
155			{
156			EVP_DigestUpdate(ctx,(const unsigned char *)in,
157				(unsigned int)ret);
158			}
159		}
160	BIO_clear_retry_flags(b);
161	BIO_copy_next_retry(b);
162	return(ret);
163	}
164
165static long md_ctrl(BIO *b, int cmd, long num, void *ptr)
166	{
167	EVP_MD_CTX *ctx,*dctx,**pctx;
168	const EVP_MD **ppmd;
169	EVP_MD *md;
170	long ret=1;
171	BIO *dbio;
172
173	ctx=b->ptr;
174
175	switch (cmd)
176		{
177	case BIO_CTRL_RESET:
178		if (b->init)
179			ret = EVP_DigestInit_ex(ctx,ctx->digest, NULL);
180		else
181			ret=0;
182		if (ret > 0)
183			ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
184		break;
185	case BIO_C_GET_MD:
186		if (b->init)
187			{
188			ppmd=ptr;
189			*ppmd=ctx->digest;
190			}
191		else
192			ret=0;
193		break;
194	case BIO_C_GET_MD_CTX:
195		if (b->init)
196			{
197			pctx=ptr;
198			*pctx=ctx;
199			}
200		else
201			ret=0;
202		break;
203	case BIO_C_SET_MD_CTX:
204		if (b->init)
205			b->ptr=ptr;
206		else
207			ret=0;
208		break;
209	case BIO_C_DO_STATE_MACHINE:
210		BIO_clear_retry_flags(b);
211		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
212		BIO_copy_next_retry(b);
213		break;
214
215	case BIO_C_SET_MD:
216		md=ptr;
217		ret = EVP_DigestInit_ex(ctx,md, NULL);
218		if (ret > 0)
219			b->init=1;
220		break;
221	case BIO_CTRL_DUP:
222		dbio=ptr;
223		dctx=dbio->ptr;
224		EVP_MD_CTX_copy_ex(dctx,ctx);
225		b->init=1;
226		break;
227	default:
228		ret=BIO_ctrl(b->next_bio,cmd,num,ptr);
229		break;
230		}
231	return(ret);
232	}
233
234static long md_callback_ctrl(BIO *b, int cmd, bio_info_cb *fp)
235	{
236	long ret=1;
237
238	if (b->next_bio == NULL) return(0);
239	switch (cmd)
240		{
241	default:
242		ret=BIO_callback_ctrl(b->next_bio,cmd,fp);
243		break;
244		}
245	return(ret);
246	}
247
248static int md_gets(BIO *bp, char *buf, int size)
249	{
250	EVP_MD_CTX *ctx;
251	unsigned int ret;
252
253
254	ctx=bp->ptr;
255	if (size < ctx->digest->md_size)
256		return(0);
257	EVP_DigestFinal_ex(ctx,(unsigned char *)buf,&ret);
258	return((int)ret);
259	}
260
261/*
262static int md_puts(bp,str)
263BIO *bp;
264char *str;
265	{
266	return(-1);
267	}
268*/
269
270