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
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
|
/* $OpenBSD: ssh2.c,v 1.3 2009/07/12 18:04:03 jsg Exp $ */
/*
* ssh2.c
*
* Copyright (c) 2005 Marius Eriksen <marius@openbsd.org>
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
#include <sys/types.h>
#include <sys/uio.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <openssl/ssl.h>
#include <openssl/des.h>
#include <openssl/md5.h>
#include <errno.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>
#include <resolv.h>
#include <err.h>
#include "key.h"
#include "ssh2.h"
#define GET_32BIT(cp) (((u_long)(u_char)(cp)[0] << 24) | \
((u_long)(u_char)(cp)[1] << 16) | \
((u_long)(u_char)(cp)[2] << 8) | \
((u_long)(u_char)(cp)[3]))
/* From OpenSSH */
static int
_uudecode(const char *src, u_char *target, size_t targsize)
{
int len;
char *encoded, *p;
/* copy the 'readonly' source */
if ((encoded = strdup(src)) == NULL)
err(1, "strdup");
/* skip whitespace and data */
for (p = encoded; *p == ' ' || *p == '\t'; p++)
;
for (; *p != '\0' && *p != ' ' && *p != '\t'; p++)
;
/* and remove trailing whitespace because __b64_pton needs this */
*p = '\0';
len = __b64_pton(encoded, target, targsize);
free(encoded);
return len;
}
/*
* Small compatibility layer for the OpenSSH buffers. Only what we
* need here.
*/
static int
_keyfromstr(char *str, int len)
{
if (strncmp(str, "rsa", len) == 0 ||
strncmp(str, "ssh-rsa", len) == 0)
return KEY_RSA;
else if (strncmp(str, "dsa", len) == 0 ||
strncmp(str, "ssh-dss", len) == 0)
return KEY_DSA;
return (-1);
}
static int
_read_int(struct iovec *iov, int *ival)
{
iov->iov_len -= 4;
if (iov->iov_len < 0)
return (-1);
*ival = GET_32BIT((u_char *)iov->iov_base);
iov->iov_base = (u_char*)iov->iov_base + 4;
return (0);
}
static int
_read_opaque(struct iovec *iov, u_char **buf, int *len)
{
if (_read_int(iov, len) < 0 || *len < 0)
return (-1);
iov->iov_len -= *len;
if (iov->iov_len < 0)
return (-1);
*buf = iov->iov_base;
iov->iov_base = (u_char*)iov->iov_base + *len;
return (0);
}
static int
_read_bignum(struct iovec *iov, BIGNUM *bn)
{
u_char *bp;
int blen;
if (_read_opaque(iov, &bp, &blen) < 0)
return (-1);
if ((blen > 0 && bp[0] & 0x80) || /* No negative values */
(blen > 8*1024)) /* Too large */
return (-1);
BN_bin2bn(bp, blen, bn);
return (0);
}
int
ssh2_load_public(struct key *k, struct iovec *iovp)
{
int len, keytype, error = 0;
u_char *bp;
struct iovec iov;
/* iov->iov_base is NULL terminated */
char *cp0, *savep = NULL, *cp = iovp->iov_base;
if ((cp0 = strchr(cp, ' ')) == NULL)
return (-1);
len = cp0 - cp;
if ((keytype = _keyfromstr(cp, len)) < 0)
return (-1);
/* cp0 is a space (' '), so we have at least one more */
cp = cp0 + 1;
len = 2*strlen(cp);
if ((savep = iov.iov_base = malloc(len)) == NULL)
err(1, "malloc(%d)", len);
iov.iov_len = _uudecode(cp, iov.iov_base, len);
if (_read_opaque(&iov, &bp, &len) < 0 ||
keytype != _keyfromstr(bp, len)) {
error = -1;
goto out;
}
k->type = keytype;
switch (keytype) {
case KEY_RSA: {
RSA *rsa;
if ((rsa = RSA_new()) == NULL ||
(rsa->e = BN_new()) == NULL ||
(rsa->n = BN_new()) == NULL)
errx(1, "BN_new");
if (_read_bignum(&iov, rsa->e) < 0 ||
_read_bignum(&iov, rsa->n) < 0) {
error = -1;
RSA_free(rsa);
goto out;
}
k->data = (void *)rsa;
break;
}
case KEY_DSA: {
DSA *dsa;
if ((dsa = DSA_new()) == NULL ||
(dsa->p = BN_new()) == NULL ||
(dsa->q = BN_new()) == NULL ||
(dsa->g = BN_new()) == NULL ||
(dsa->pub_key = BN_new()) == NULL)
errx(1, "BN_new");
if (_read_bignum(&iov, dsa->p) < 0 ||
_read_bignum(&iov, dsa->q) < 0 ||
_read_bignum(&iov, dsa->g) < 0 ||
_read_bignum(&iov, dsa->pub_key) < 0) {
error = -1;
DSA_free(dsa);
goto out;
}
k->data = (void *)dsa;
break;
}
default:
error = -1;
}
#if 0
if (iov->iov_len != 0)
/* Sanity check. */
return (-1);
#endif
out:
if (savep != NULL)
free(savep);
return (error);
}
|