2 15cacd92 2019-03-29 martijn * Copyright (c) 2019 Martijn van Duren <martijn@openbsd.org>
4 15cacd92 2019-03-29 martijn * Permission to use, copy, modify, and distribute this software for any
5 15cacd92 2019-03-29 martijn * purpose with or without fee is hereby granted, provided that the above
6 15cacd92 2019-03-29 martijn * copyright notice and this permission notice appear in all copies.
8 15cacd92 2019-03-29 martijn * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
9 15cacd92 2019-03-29 martijn * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
10 15cacd92 2019-03-29 martijn * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
11 15cacd92 2019-03-29 martijn * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
12 15cacd92 2019-03-29 martijn * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
13 15cacd92 2019-03-29 martijn * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
14 15cacd92 2019-03-29 martijn * OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
16 c75461cd 2019-03-29 martijn #include <sys/tree.h>
17 aeda4d4e 2019-03-28 martijn #include <sys/types.h>
18 a248a3c1 2019-03-27 martijn #include <sys/socket.h>
20 2e3e5d5f 2019-03-29 martijn #include <arpa/inet.h>
21 a248a3c1 2019-03-27 martijn #include <errno.h>
22 aeda4d4e 2019-03-28 martijn #include <event.h>
23 a287838f 2019-03-31 martijn #include <inttypes.h>
24 a248a3c1 2019-03-27 martijn #include <netdb.h>
25 a248a3c1 2019-03-27 martijn #include <stdlib.h>
26 a248a3c1 2019-03-27 martijn #include <stdio.h>
27 a248a3c1 2019-03-27 martijn #include <string.h>
28 b633fa4c 2019-03-29 martijn #include <syslog.h>
29 a248a3c1 2019-03-27 martijn #include <unistd.h>
30 aeda4d4e 2019-03-28 martijn #include <asr.h>
32 b633fa4c 2019-03-29 martijn #include "log.h"
33 a248a3c1 2019-03-27 martijn #include "smtp_proc.h"
35 aeda4d4e 2019-03-28 martijn struct dnsbl_session;
37 aeda4d4e 2019-03-28 martijn struct dnsbl_query {
38 aeda4d4e 2019-03-28 martijn struct asr_query *query;
39 aeda4d4e 2019-03-28 martijn struct event_asr *event;
40 76e3b8e2 2019-03-28 martijn struct event timeout;
41 aeda4d4e 2019-03-28 martijn int resolved;
42 aeda4d4e 2019-03-28 martijn int blacklist;
43 aeda4d4e 2019-03-28 martijn struct dnsbl_session *session;
46 aeda4d4e 2019-03-28 martijn struct dnsbl_session {
47 aeda4d4e 2019-03-28 martijn uint64_t reqid;
48 aeda4d4e 2019-03-28 martijn uint64_t token;
49 2e3e5d5f 2019-03-29 martijn char addr[INET6_ADDRSTRLEN];
50 5468729e 2019-03-29 martijn int listed;
51 a287838f 2019-03-31 martijn int set_header;
52 a287838f 2019-03-31 martijn int logged_mark;
53 aeda4d4e 2019-03-28 martijn struct dnsbl_query *query;
54 c75461cd 2019-03-29 martijn RB_ENTRY(dnsbl_session) entry;
57 c75461cd 2019-03-29 martijn RB_HEAD(dnsbl_sessions, dnsbl_session) dnsbl_sessions = RB_INITIALIZER(NULL);
58 c75461cd 2019-03-29 martijn RB_PROTOTYPE(dnsbl_sessions, dnsbl_session, entry, dnsbl_session_cmp);
60 a248a3c1 2019-03-27 martijn static char **blacklists = NULL;
61 a248a3c1 2019-03-27 martijn static size_t nblacklists = 0;
62 5468729e 2019-03-29 martijn static int markspam = 0;
64 a248a3c1 2019-03-27 martijn void usage(void);
65 42a4c512 2019-03-28 martijn void dnsbl_connect(char *, int, struct timespec *, char *, char *, uint64_t,
66 03a6f52a 2019-03-29 martijn uint64_t, char *, struct inx_addr *);
67 a287838f 2019-03-31 martijn void dnsbl_data(char *, int, struct timespec *, char *, char *, uint64_t,
68 a287838f 2019-03-31 martijn uint64_t);
69 5468729e 2019-03-29 martijn void dnsbl_dataline(char *, int, struct timespec *, char *, char *, uint64_t,
70 5468729e 2019-03-29 martijn uint64_t, char *);
71 c75461cd 2019-03-29 martijn void dnsbl_disconnect(char *, int, struct timespec *, char *, char *, uint64_t);
72 aeda4d4e 2019-03-28 martijn void dnsbl_resolve(struct asr_result *, void *);
73 76e3b8e2 2019-03-28 martijn void dnsbl_timeout(int, short, void *);
74 5468729e 2019-03-29 martijn void dnsbl_session_query_done(struct dnsbl_session *);
75 aeda4d4e 2019-03-28 martijn void dnsbl_session_free(struct dnsbl_session *);
76 c75461cd 2019-03-29 martijn int dnsbl_session_cmp(struct dnsbl_session *, struct dnsbl_session *);
79 a248a3c1 2019-03-27 martijn main(int argc, char *argv[])
83 b633fa4c 2019-03-29 martijn int debug = 0;
85 5905c22e 2019-03-29 martijn while ((ch = getopt(argc, argv, "dm")) != -1) {
86 a248a3c1 2019-03-27 martijn switch (ch) {
87 b633fa4c 2019-03-29 martijn case 'd':
88 b633fa4c 2019-03-29 martijn debug = 1;
90 5468729e 2019-03-29 martijn case 'm':
91 5468729e 2019-03-29 martijn markspam = 1;
98 b633fa4c 2019-03-29 martijn log_init(debug, LOG_MAIL);
99 b633fa4c 2019-03-29 martijn if (pledge("stdio dns", NULL) == -1)
100 b633fa4c 2019-03-29 martijn fatal("pledge");
102 96a01110 2019-03-29 martijn if ((nblacklists = argc - optind) == 0)
103 b633fa4c 2019-03-29 martijn fatalx("No blacklist specified");
105 deafb383 2019-03-29 martijn if ((blacklists = calloc(nblacklists, sizeof(*blacklists))) == NULL)
106 b633fa4c 2019-03-29 martijn fatal(NULL);
107 deafb383 2019-03-29 martijn for (i = 0; i < nblacklists; i++)
108 deafb383 2019-03-29 martijn blacklists[i] = argv[optind + i];
110 a248a3c1 2019-03-27 martijn smtp_register_filter_connect(dnsbl_connect);
111 a287838f 2019-03-31 martijn if (markspam) {
112 a287838f 2019-03-31 martijn smtp_register_filter_data(dnsbl_data);
113 deafb383 2019-03-29 martijn smtp_register_filter_dataline(dnsbl_dataline);
115 c75461cd 2019-03-29 martijn smtp_in_register_report_disconnect(dnsbl_disconnect);
116 b633fa4c 2019-03-29 martijn smtp_run(debug);
118 a248a3c1 2019-03-27 martijn return 0;
122 42a4c512 2019-03-28 martijn dnsbl_connect(char *type, int version, struct timespec *tm, char *direction,
123 03a6f52a 2019-03-29 martijn char *phase, uint64_t reqid, uint64_t token, char *hostname,
124 03a6f52a 2019-03-29 martijn struct inx_addr *xaddr)
126 aeda4d4e 2019-03-28 martijn struct dnsbl_session *session;
127 76e3b8e2 2019-03-28 martijn struct timeval timeout = {1, 0};
128 a248a3c1 2019-03-27 martijn char query[255];
129 a248a3c1 2019-03-27 martijn u_char *addr;
130 57cbfccc 2019-03-27 martijn int i, try;
132 aeda4d4e 2019-03-28 martijn if ((session = calloc(1, sizeof(*session))) == NULL)
133 b633fa4c 2019-03-29 martijn fatal(NULL);
134 aeda4d4e 2019-03-28 martijn if ((session->query = calloc(nblacklists, sizeof(*(session->query))))
135 aeda4d4e 2019-03-28 martijn == NULL)
136 b633fa4c 2019-03-29 martijn fatal(NULL);
137 aeda4d4e 2019-03-28 martijn session->reqid = reqid;
138 aeda4d4e 2019-03-28 martijn session->token = token;
139 5468729e 2019-03-29 martijn session->listed = -1;
140 a287838f 2019-03-31 martijn session->set_header = 0;
141 a287838f 2019-03-31 martijn session->logged_mark = 0;
142 2e3e5d5f 2019-03-29 martijn if (inet_ntop(xaddr->af, xaddr->af == AF_INET ?
143 2e3e5d5f 2019-03-29 martijn (void *)&(xaddr->addr) : (void *)&(xaddr->addr6), session->addr,
144 2e3e5d5f 2019-03-29 martijn sizeof(session->addr)) == NULL)
145 2e3e5d5f 2019-03-29 martijn fatal("inet_ntop");
147 c75461cd 2019-03-29 martijn RB_INSERT(dnsbl_sessions, &dnsbl_sessions, session);
149 03a6f52a 2019-03-29 martijn if (xaddr->af == AF_INET)
150 03a6f52a 2019-03-29 martijn addr = (u_char *)&(xaddr->addr);
152 03a6f52a 2019-03-29 martijn addr = (u_char *)&(xaddr->addr6);
153 a248a3c1 2019-03-27 martijn for (i = 0; i < nblacklists; i++) {
154 03a6f52a 2019-03-29 martijn if (xaddr->af == AF_INET) {
155 a248a3c1 2019-03-27 martijn if (snprintf(query, sizeof(query), "%u.%u.%u.%u.%s",
156 a248a3c1 2019-03-27 martijn addr[3], addr[2], addr[1], addr[0],
157 a248a3c1 2019-03-27 martijn blacklists[i]) >= sizeof(query))
158 b633fa4c 2019-03-29 martijn fatalx("Can't create query, domain too long");
159 03a6f52a 2019-03-29 martijn } else if (xaddr->af == AF_INET6) {
160 a248a3c1 2019-03-27 martijn if (snprintf(query, sizeof(query), "%hhx.%hhx.%hhx.%hhx"
161 a248a3c1 2019-03-27 martijn ".%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx"
162 a248a3c1 2019-03-27 martijn ".%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx"
163 a248a3c1 2019-03-27 martijn ".%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%hhx.%s",
164 a248a3c1 2019-03-27 martijn (u_char) (addr[15] & 0xf), (u_char) (addr[15] >> 4),
165 a248a3c1 2019-03-27 martijn (u_char) (addr[14] & 0xf), (u_char) (addr[14] >> 4),
166 a248a3c1 2019-03-27 martijn (u_char) (addr[13] & 0xf), (u_char) (addr[13] >> 4),
167 a248a3c1 2019-03-27 martijn (u_char) (addr[12] & 0xf), (u_char) (addr[12] >> 4),
168 a248a3c1 2019-03-27 martijn (u_char) (addr[11] & 0xf), (u_char) (addr[11] >> 4),
169 a248a3c1 2019-03-27 martijn (u_char) (addr[10] & 0xf), (u_char) (addr[10] >> 4),
170 a248a3c1 2019-03-27 martijn (u_char) (addr[9] & 0xf), (u_char) (addr[9] >> 4),
171 a248a3c1 2019-03-27 martijn (u_char) (addr[8] & 0xf), (u_char) (addr[8] >> 4),
172 a248a3c1 2019-03-27 martijn (u_char) (addr[7] & 0xf), (u_char) (addr[8] >> 4),
173 a248a3c1 2019-03-27 martijn (u_char) (addr[6] & 0xf), (u_char) (addr[7] >> 4),
174 a248a3c1 2019-03-27 martijn (u_char) (addr[5] & 0xf), (u_char) (addr[5] >> 4),
175 a248a3c1 2019-03-27 martijn (u_char) (addr[4] & 0xf), (u_char) (addr[4] >> 4),
176 a248a3c1 2019-03-27 martijn (u_char) (addr[3] & 0xf), (u_char) (addr[3] >> 4),
177 a248a3c1 2019-03-27 martijn (u_char) (addr[2] & 0xf), (u_char) (addr[2] >> 4),
178 a248a3c1 2019-03-27 martijn (u_char) (addr[1] & 0xf), (u_char) (addr[1] >> 4),
179 a248a3c1 2019-03-27 martijn (u_char) (addr[0] & 0xf), (u_char) (addr[0] >> 4),
180 a248a3c1 2019-03-27 martijn blacklists[i]) >= sizeof(query))
181 b633fa4c 2019-03-29 martijn fatalx( "Can't create query, domain too long");
183 b633fa4c 2019-03-29 martijn fatalx("Invalid address family received");
185 aeda4d4e 2019-03-28 martijn session->query[i].query = gethostbyname_async(query, NULL);
186 aeda4d4e 2019-03-28 martijn session->query[i].event = event_asr_run(session->query[i].query,
187 aeda4d4e 2019-03-28 martijn dnsbl_resolve, &(session->query[i]));
188 aeda4d4e 2019-03-28 martijn session->query[i].blacklist = i;
189 aeda4d4e 2019-03-28 martijn session->query[i].session = session;
190 76e3b8e2 2019-03-28 martijn evtimer_set(&(session->query[i].timeout), dnsbl_timeout,
191 76e3b8e2 2019-03-28 martijn &(session->query[i]));
192 76e3b8e2 2019-03-28 martijn evtimer_add(&(session->query[i].timeout), &timeout);
197 aeda4d4e 2019-03-28 martijn dnsbl_resolve(struct asr_result *result, void *arg)
199 aeda4d4e 2019-03-28 martijn struct dnsbl_query *query = arg;
200 aeda4d4e 2019-03-28 martijn struct dnsbl_session *session = query->session;
201 aeda4d4e 2019-03-28 martijn int i, blacklist;
203 aeda4d4e 2019-03-28 martijn query->resolved = 1;
204 aeda4d4e 2019-03-28 martijn query->event = NULL;
205 aeda4d4e 2019-03-28 martijn query->query = NULL;
206 76e3b8e2 2019-03-28 martijn evtimer_del(&(query->timeout));
207 aeda4d4e 2019-03-28 martijn if (result->ar_hostent != NULL) {
208 5468729e 2019-03-29 martijn if (!markspam) {
209 5468729e 2019-03-29 martijn smtp_filter_disconnect(session->reqid, session->token,
210 f15f6435 2019-03-29 martijn "Listed at %s", blacklists[query->blacklist]);
211 a287838f 2019-03-31 martijn log_info("%016"PRIx64" listed at %s: rejected",
212 a287838f 2019-03-31 martijn session->reqid, blacklists[query->blacklist]);
213 5468729e 2019-03-29 martijn dnsbl_session_free(session);
214 5468729e 2019-03-29 martijn } else {
215 5468729e 2019-03-29 martijn dnsbl_session_query_done(session);
216 5468729e 2019-03-29 martijn session->listed = query->blacklist;
217 5468729e 2019-03-29 martijn smtp_filter_proceed(session->reqid, session->token);
218 a287838f 2019-03-31 martijn /* Delay logging until we have a message */
222 cf6af233 2019-03-28 martijn if (result->ar_h_errno != HOST_NOT_FOUND) {
223 cf6af233 2019-03-28 martijn smtp_filter_disconnect(session->reqid, session->token,
224 76e3b8e2 2019-03-28 martijn "DNS error on %s", blacklists[query->blacklist]);
225 cf6af233 2019-03-28 martijn dnsbl_session_free(session);
229 aeda4d4e 2019-03-28 martijn for (i = 0; i < nblacklists; i++) {
230 aeda4d4e 2019-03-28 martijn if (!session->query[i].resolved)
233 aeda4d4e 2019-03-28 martijn smtp_filter_proceed(session->reqid, session->token);
234 a287838f 2019-03-31 martijn log_info("%016"PRIx64" not listed", session->reqid);
238 76e3b8e2 2019-03-28 martijn dnsbl_timeout(int fd, short event, void *arg)
240 76e3b8e2 2019-03-28 martijn struct dnsbl_query *query = arg;
241 76e3b8e2 2019-03-28 martijn struct dnsbl_session *session = query->session;
243 76e3b8e2 2019-03-28 martijn smtp_filter_disconnect(session->reqid, session->token,
244 76e3b8e2 2019-03-28 martijn "DNS timeout on %s", blacklists[query->blacklist]);
245 76e3b8e2 2019-03-28 martijn dnsbl_session_free(session);
249 c75461cd 2019-03-29 martijn dnsbl_disconnect(char *type, int version, struct timespec *tm, char *direction,
250 c75461cd 2019-03-29 martijn char *phase, uint64_t reqid)
252 c75461cd 2019-03-29 martijn struct dnsbl_session *session, search;
254 c75461cd 2019-03-29 martijn search.reqid = reqid;
255 c75461cd 2019-03-29 martijn if ((session = RB_FIND(dnsbl_sessions, &dnsbl_sessions, &search)) != NULL)
256 c75461cd 2019-03-29 martijn dnsbl_session_free(session);
260 a287838f 2019-03-31 martijn dnsbl_data(char *type, int version, struct timespec *tm, char *direction,
261 a287838f 2019-03-31 martijn char *phase, uint64_t reqid, uint64_t token)
263 a287838f 2019-03-31 martijn struct dnsbl_session *session, search;
265 a287838f 2019-03-31 martijn search.reqid = reqid;
266 a287838f 2019-03-31 martijn session = RB_FIND(dnsbl_sessions, &dnsbl_sessions, &search);
268 a287838f 2019-03-31 martijn if (session->listed != -1) {
269 a287838f 2019-03-31 martijn if (!session->logged_mark) {
270 a287838f 2019-03-31 martijn log_info("%016"PRIx64" listed at %s: Marking as spam",
271 a287838f 2019-03-31 martijn session->reqid, blacklists[session->listed]);
272 a287838f 2019-03-31 martijn session->logged_mark = 1;
274 a287838f 2019-03-31 martijn session->set_header = 1;
276 a287838f 2019-03-31 martijn smtp_filter_proceed(reqid, token);
280 5468729e 2019-03-29 martijn dnsbl_dataline(char *type, int version, struct timespec *tm, char *direction,
281 5468729e 2019-03-29 martijn char *phase, uint64_t reqid, uint64_t token, char *line)
283 5468729e 2019-03-29 martijn struct dnsbl_session *session, search;
285 5468729e 2019-03-29 martijn search.reqid = reqid;
286 5468729e 2019-03-29 martijn session = RB_FIND(dnsbl_sessions, &dnsbl_sessions, &search);
288 a287838f 2019-03-31 martijn if (session->set_header) {
289 5468729e 2019-03-29 martijn smtp_filter_dataline(reqid, token, "X-Spam: yes");
290 5468729e 2019-03-29 martijn smtp_filter_dataline(reqid, token, "X-Spam-DNSBL: Listed at %s",
291 5468729e 2019-03-29 martijn blacklists[session->listed]);
292 a287838f 2019-03-31 martijn session->set_header = 0;
295 5468729e 2019-03-29 martijn smtp_filter_dataline(reqid, token, "%s", line);
299 5468729e 2019-03-29 martijn dnsbl_session_query_done(struct dnsbl_session *session)
303 aeda4d4e 2019-03-28 martijn for (i = 0; i < nblacklists; i++) {
304 76e3b8e2 2019-03-28 martijn if (!session->query[i].resolved) {
305 aeda4d4e 2019-03-28 martijn event_asr_abort(session->query[i].event);
306 76e3b8e2 2019-03-28 martijn evtimer_del(&(session->query[i].timeout));
307 4dce78a6 2019-04-05 martijn session->query[i].resolved = 1;
313 5468729e 2019-03-29 martijn dnsbl_session_free(struct dnsbl_session *session)
315 5468729e 2019-03-29 martijn RB_REMOVE(dnsbl_sessions, &dnsbl_sessions, session);
316 5468729e 2019-03-29 martijn dnsbl_session_query_done(session);
317 aeda4d4e 2019-03-28 martijn free(session->query);
318 aeda4d4e 2019-03-28 martijn free(session);
322 c75461cd 2019-03-29 martijn dnsbl_session_cmp(struct dnsbl_session *s1, struct dnsbl_session *s2)
324 c75461cd 2019-03-29 martijn return (s1->reqid < s2->reqid ? -1 : s1->reqid > s2->reqid);
327 f8356fc3 2019-03-28 martijn __dead void
328 a248a3c1 2019-03-27 martijn usage(void)
330 deafb383 2019-03-29 martijn fprintf(stderr, "usage: %s [-m] blacklist [...]\n",
331 a248a3c1 2019-03-27 martijn getprogname());
332 a248a3c1 2019-03-27 martijn exit(1);
335 c75461cd 2019-03-29 martijn RB_GENERATE(dnsbl_sessions, dnsbl_session, entry, dnsbl_session_cmp);
