pem_seal.c revision 55714 
1/* crypto/pem/pem_seal.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#ifndef NO_RSA
60#include <stdio.h>
61#include "cryptlib.h"
62#include <openssl/evp.h>
63#include <openssl/rand.h>
64#include <openssl/objects.h>
65#include <openssl/x509.h>
66#include <openssl/pem.h>
67
68int PEM_SealInit(PEM_ENCODE_SEAL_CTX *ctx, EVP_CIPHER *type, EVP_MD *md_type,
69	     unsigned char **ek, int *ekl, unsigned char *iv, EVP_PKEY **pubk,
70	     int npubk)
71	{
72	unsigned char key[EVP_MAX_KEY_LENGTH];
73	int ret= -1;
74	int i,j,max=0;
75	char *s=NULL;
76
77	for (i=0; i<npubk; i++)
78		{
79		if (pubk[i]->type != EVP_PKEY_RSA)
80			{
81			PEMerr(PEM_F_PEM_SEALINIT,PEM_R_PUBLIC_KEY_NO_RSA);
82			goto err;
83			}
84		j=RSA_size(pubk[i]->pkey.rsa);
85		if (j > max) max=j;
86		}
87	s=(char *)Malloc(max*2);
88	if (s == NULL)
89		{
90		PEMerr(PEM_F_PEM_SEALINIT,ERR_R_MALLOC_FAILURE);
91		goto err;
92		}
93
94	EVP_EncodeInit(&(ctx->encode));
95	EVP_SignInit(&(ctx->md),md_type);
96
97	ret=EVP_SealInit(&(ctx->cipher),type,ek,ekl,iv,pubk,npubk);
98	if (!ret) goto err;
99
100	/* base64 encode the keys */
101	for (i=0; i<npubk; i++)
102		{
103		j=EVP_EncodeBlock((unsigned char *)s,ek[i],
104			RSA_size(pubk[i]->pkey.rsa));
105		ekl[i]=j;
106		memcpy(ek[i],s,j+1);
107		}
108
109	ret=npubk;
110err:
111	if (s != NULL) Free(s);
112	memset(key,0,EVP_MAX_KEY_LENGTH);
113	return(ret);
114	}
115
116void PEM_SealUpdate(PEM_ENCODE_SEAL_CTX *ctx, unsigned char *out, int *outl,
117	     unsigned char *in, int inl)
118	{
119	unsigned char buffer[1600];
120	int i,j;
121
122	*outl=0;
123	EVP_SignUpdate(&(ctx->md),in,inl);
124	for (;;)
125		{
126		if (inl <= 0) break;
127		if (inl > 1200)
128			i=1200;
129		else
130			i=inl;
131		EVP_EncryptUpdate(&(ctx->cipher),buffer,&j,in,i);
132		EVP_EncodeUpdate(&(ctx->encode),out,&j,buffer,j);
133		*outl+=j;
134		out+=j;
135		in+=i;
136		inl-=i;
137		}
138	}
139
140int PEM_SealFinal(PEM_ENCODE_SEAL_CTX *ctx, unsigned char *sig, int *sigl,
141	     unsigned char *out, int *outl, EVP_PKEY *priv)
142	{
143	unsigned char *s=NULL;
144	int ret=0,j;
145	unsigned int i;
146
147	if (priv->type != EVP_PKEY_RSA)
148		{
149		PEMerr(PEM_F_PEM_SEALFINAL,PEM_R_PUBLIC_KEY_NO_RSA);
150		goto err;
151		}
152	i=RSA_size(priv->pkey.rsa);
153	if (i < 100) i=100;
154	s=(unsigned char *)Malloc(i*2);
155	if (s == NULL)
156		{
157		PEMerr(PEM_F_PEM_SEALFINAL,ERR_R_MALLOC_FAILURE);
158		goto err;
159		}
160
161	EVP_EncryptFinal(&(ctx->cipher),s,(int *)&i);
162	EVP_EncodeUpdate(&(ctx->encode),out,&j,s,i);
163	*outl=j;
164	out+=j;
165	EVP_EncodeFinal(&(ctx->encode),out,&j);
166	*outl+=j;
167
168	if (!EVP_SignFinal(&(ctx->md),s,&i,priv)) goto err;
169	*sigl=EVP_EncodeBlock(sig,s,i);
170
171	ret=1;
172err:
173	memset((char *)&(ctx->md),0,sizeof(ctx->md));
174	memset((char *)&(ctx->cipher),0,sizeof(ctx->cipher));
175	if (s != NULL) Free(s);
176	return(ret);
177	}
178#endif
179