1 /*
2 * pgp-info.c
3 * Provide info about PGP data.
4 *
5 * Copyright (c) 2005 Marko Kreen
6 * All rights reserved.
7 *
8 * Redistribution and use in source and binary forms, with or without
9 * modification, are permitted provided that the following conditions
10 * are met:
11 * 1. Redistributions of source code must retain the above copyright
12 * notice, this list of conditions and the following disclaimer.
13 * 2. Redistributions in binary form must reproduce the above copyright
14 * notice, this list of conditions and the following disclaimer in the
15 * documentation and/or other materials provided with the distribution.
16 *
17 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
18 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
19 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
20 * ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
21 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
22 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
23 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
24 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
25 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
26 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
27 * SUCH DAMAGE.
28 *
29 * contrib/pgcrypto/pgp-info.c
30 */
31 #include "postgres.h"
32
33 #include "px.h"
34 #include "mbuf.h"
35 #include "pgp.h"
36
37 static int
read_pubkey_keyid(PullFilter * pkt,uint8 * keyid_buf)38 read_pubkey_keyid(PullFilter *pkt, uint8 *keyid_buf)
39 {
40 int res;
41 PGP_PubKey *pk = NULL;
42
43 res = _pgp_read_public_key(pkt, &pk);
44 if (res < 0)
45 goto err;
46
47 /* skip secret key part, if it exists */
48 res = pgp_skip_packet(pkt);
49 if (res < 0)
50 goto err;
51
52 /* is it encryption key */
53 switch (pk->algo)
54 {
55 case PGP_PUB_ELG_ENCRYPT:
56 case PGP_PUB_RSA_ENCRYPT:
57 case PGP_PUB_RSA_ENCRYPT_SIGN:
58 memcpy(keyid_buf, pk->key_id, 8);
59 res = 1;
60 break;
61 default:
62 res = 0;
63 }
64
65 err:
66 pgp_key_free(pk);
67 return res;
68 }
69
70 static int
read_pubenc_keyid(PullFilter * pkt,uint8 * keyid_buf)71 read_pubenc_keyid(PullFilter *pkt, uint8 *keyid_buf)
72 {
73 uint8 ver;
74 int res;
75
76 GETBYTE(pkt, ver);
77 if (ver != 3)
78 return -1;
79
80 res = pullf_read_fixed(pkt, 8, keyid_buf);
81 if (res < 0)
82 return res;
83
84 return pgp_skip_packet(pkt);
85 }
86
87 static const char hextbl[] = "0123456789ABCDEF";
88
89 static int
print_key(uint8 * keyid,char * dst)90 print_key(uint8 *keyid, char *dst)
91 {
92 int i;
93 unsigned c;
94
95 for (i = 0; i < 8; i++)
96 {
97 c = keyid[i];
98 *dst++ = hextbl[(c >> 4) & 0x0F];
99 *dst++ = hextbl[c & 0x0F];
100 }
101 *dst = 0;
102 return 8 * 2;
103 }
104
105 static const uint8 any_key[] =
106 {0, 0, 0, 0, 0, 0, 0, 0};
107
108 /*
109 * dst should have room for 17 bytes
110 */
111 int
pgp_get_keyid(MBuf * pgp_data,char * dst)112 pgp_get_keyid(MBuf *pgp_data, char *dst)
113 {
114 int res;
115 PullFilter *src;
116 PullFilter *pkt = NULL;
117 int len;
118 uint8 tag;
119 int got_pub_key = 0,
120 got_symenc_key = 0,
121 got_pubenc_key = 0;
122 int got_data = 0;
123 uint8 keyid_buf[8];
124 int got_main_key = 0;
125
126
127 res = pullf_create_mbuf_reader(&src, pgp_data);
128 if (res < 0)
129 return res;
130
131 while (1)
132 {
133 res = pgp_parse_pkt_hdr(src, &tag, &len, 0);
134 if (res <= 0)
135 break;
136 res = pgp_create_pkt_reader(&pkt, src, len, res, NULL);
137 if (res < 0)
138 break;
139
140 switch (tag)
141 {
142 case PGP_PKT_SECRET_KEY:
143 case PGP_PKT_PUBLIC_KEY:
144 /* main key is for signing, so ignore it */
145 if (!got_main_key)
146 {
147 got_main_key = 1;
148 res = pgp_skip_packet(pkt);
149 }
150 else
151 res = PXE_PGP_MULTIPLE_KEYS;
152 break;
153 case PGP_PKT_SECRET_SUBKEY:
154 case PGP_PKT_PUBLIC_SUBKEY:
155 res = read_pubkey_keyid(pkt, keyid_buf);
156 if (res < 0)
157 break;
158 if (res > 0)
159 got_pub_key++;
160 break;
161 case PGP_PKT_PUBENCRYPTED_SESSKEY:
162 got_pubenc_key++;
163 res = read_pubenc_keyid(pkt, keyid_buf);
164 break;
165 case PGP_PKT_SYMENCRYPTED_DATA:
166 case PGP_PKT_SYMENCRYPTED_DATA_MDC:
167 /* don't skip it, just stop */
168 got_data = 1;
169 break;
170 case PGP_PKT_SYMENCRYPTED_SESSKEY:
171 got_symenc_key++;
172 /* fallthru */
173 case PGP_PKT_SIGNATURE:
174 case PGP_PKT_MARKER:
175 case PGP_PKT_TRUST:
176 case PGP_PKT_USER_ID:
177 case PGP_PKT_USER_ATTR:
178 case PGP_PKT_PRIV_61:
179 res = pgp_skip_packet(pkt);
180 break;
181 default:
182 res = PXE_PGP_CORRUPT_DATA;
183 }
184
185 if (pkt)
186 pullf_free(pkt);
187 pkt = NULL;
188
189 if (res < 0 || got_data)
190 break;
191 }
192
193 pullf_free(src);
194 if (pkt)
195 pullf_free(pkt);
196
197 if (res < 0)
198 return res;
199
200 /* now check sanity */
201 if (got_pub_key && got_pubenc_key)
202 res = PXE_PGP_CORRUPT_DATA;
203
204 if (got_pub_key > 1)
205 res = PXE_PGP_MULTIPLE_KEYS;
206
207 if (got_pubenc_key > 1)
208 res = PXE_PGP_MULTIPLE_KEYS;
209
210 /*
211 * if still ok, look what we got
212 */
213 if (res >= 0)
214 {
215 if (got_pubenc_key || got_pub_key)
216 {
217 if (memcmp(keyid_buf, any_key, 8) == 0)
218 {
219 memcpy(dst, "ANYKEY", 7);
220 res = 6;
221 }
222 else
223 res = print_key(keyid_buf, dst);
224 }
225 else if (got_symenc_key)
226 {
227 memcpy(dst, "SYMKEY", 7);
228 res = 6;
229 }
230 else
231 res = PXE_PGP_NO_USABLE_KEY;
232 }
233
234 return res;
235 }
236