1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
|
/*
*
* rsa.c
*
* Author: Tatu Ylonen <ylo@cs.hut.fi>
*
* Copyright (c) 1995 Tatu Ylonen <ylo@cs.hut.fi>, Espoo, Finland
* All rights reserved
*
* Created: Fri Mar 3 22:07:06 1995 ylo
*
* Description of the RSA algorithm can be found e.g. from the following sources:
*
* Bruce Schneier: Applied Cryptography. John Wiley & Sons, 1994.
*
* Jennifer Seberry and Josed Pieprzyk: Cryptography: An Introduction to
* Computer Security. Prentice-Hall, 1989.
*
* Man Young Rhee: Cryptography and Secure Data Communications. McGraw-Hill,
* 1994.
*
* R. Rivest, A. Shamir, and L. M. Adleman: Cryptographic Communications
* System and Method. US Patent 4,405,829, 1983.
*
* Hans Riesel: Prime Numbers and Computer Methods for Factorization.
* Birkhauser, 1994.
*
* The RSA Frequently Asked Questions document by RSA Data Security, Inc., 1995.
*
* RSA in 3 lines of perl by Adam Back <aba@atlax.ex.ac.uk>, 1995, as included
* below:
*
* [gone - had to be deleted - what a pity]
*
*/
#include "includes.h"
RCSID("$Id: rsa.c,v 1.11 2000/03/17 12:40:16 damien Exp $");
#include "rsa.h"
#include "ssh.h"
#include "xmalloc.h"
#include "random.h"
int rsa_verbose = 1;
/*
* Seed OpenSSL's random number generator
*/
void
seed_rng()
{
char buf[64];
get_random_bytes(buf, sizeof(buf));
RAND_seed(buf, sizeof(buf));
memset(buf, 0, sizeof(buf));
}
int
rsa_alive()
{
RSA *key;
seed_rng();
key = RSA_generate_key(32, 3, NULL, NULL);
if (key == NULL)
return (0);
RSA_free(key);
return (1);
}
/*
* Key generation progress meter callback
*/
void
keygen_progress(int p, int n, void *arg)
{
const char progress_chars[] = ".o+O?";
if ((p < 0) || (p > (sizeof(progress_chars) - 2)))
p = sizeof(progress_chars) - 2;
putchar(progress_chars[p]);
fflush(stdout);
}
/*
* Generates RSA public and private keys. This initializes the data
* structures; they should be freed with rsa_clear_private_key and
* rsa_clear_public_key.
*/
void
rsa_generate_key(RSA *prv, RSA *pub, unsigned int bits)
{
RSA *key;
seed_rng();
if (rsa_verbose) {
printf("Generating RSA keys: ");
fflush(stdout);
key = RSA_generate_key(bits, 35, keygen_progress, NULL);
printf("\n");
} else {
key = RSA_generate_key(bits, 35, NULL, NULL);
}
if (key == NULL)
fatal("rsa_generate_key: key generation failed.");
/* Copy public key parameters */
pub->n = BN_new();
BN_copy(pub->n, key->n);
pub->e = BN_new();
BN_copy(pub->e, key->e);
/* Copy private key parameters */
prv->n = BN_new();
BN_copy(prv->n, key->n);
prv->e = BN_new();
BN_copy(prv->e, key->e);
prv->d = BN_new();
BN_copy(prv->d, key->d);
prv->p = BN_new();
BN_copy(prv->p, key->p);
prv->q = BN_new();
BN_copy(prv->q, key->q);
prv->dmp1 = BN_new();
BN_copy(prv->dmp1, key->dmp1);
prv->dmq1 = BN_new();
BN_copy(prv->dmq1, key->dmq1);
prv->iqmp = BN_new();
BN_copy(prv->iqmp, key->iqmp);
RSA_free(key);
if (rsa_verbose)
printf("Key generation complete.\n");
}
void
rsa_public_encrypt(BIGNUM *out, BIGNUM *in, RSA *key)
{
unsigned char *inbuf, *outbuf;
int len, ilen, olen;
if (BN_num_bits(key->e) < 2 || !BN_is_odd(key->e))
fatal("rsa_public_encrypt() exponent too small or not odd");
olen = BN_num_bytes(key->n);
outbuf = xmalloc(olen);
ilen = BN_num_bytes(in);
inbuf = xmalloc(ilen);
BN_bn2bin(in, inbuf);
if ((len = RSA_public_encrypt(ilen, inbuf, outbuf, key,
RSA_PKCS1_PADDING)) <= 0)
fatal("rsa_public_encrypt() failed");
BN_bin2bn(outbuf, len, out);
memset(outbuf, 0, olen);
memset(inbuf, 0, ilen);
xfree(outbuf);
xfree(inbuf);
}
void
rsa_private_decrypt(BIGNUM *out, BIGNUM *in, RSA *key)
{
unsigned char *inbuf, *outbuf;
int len, ilen, olen;
olen = BN_num_bytes(key->n);
outbuf = xmalloc(olen);
ilen = BN_num_bytes(in);
inbuf = xmalloc(ilen);
BN_bn2bin(in, inbuf);
if ((len = RSA_private_decrypt(ilen, inbuf, outbuf, key,
RSA_PKCS1_PADDING)) <= 0)
fatal("rsa_private_decrypt() failed");
BN_bin2bn(outbuf, len, out);
memset(outbuf, 0, olen);
memset(inbuf, 0, ilen);
xfree(outbuf);
xfree(inbuf);
}
/* Set whether to output verbose messages during key generation. */
void
rsa_set_verbose(int verbose)
{
rsa_verbose = verbose;
}
|
