1 /* $OpenBSD: ypldap_dns.c,v 1.8 2015/01/16 06:40:22 deraadt Exp $ */
5 * Copyright (c) 2003-2008 Henning Brauer <henning@openbsd.org>
7 * Permission to use, copy, modify, and distribute this software for any
8 * purpose with or without fee is hereby granted, provided that the above
9 * copyright notice and this permission notice appear in all copies.
11 * THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
12 * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
13 * MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
14 * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
15 * WHATSOEVER RESULTING FROM LOSS OF MIND, USE, DATA OR PROFITS, WHETHER
16 * IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING
17 * OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
20 #include <sys/types.h>
21 #include <sys/param.h>
22 #include <sys/socket.h>
26 #include <sys/queue.h>
28 #include <netinet/in.h>
29 #include <arpa/nameser.h>
45 volatile sig_atomic_t quit_dns = 0;
46 struct imsgev *iev_dns;
48 void dns_dispatch_imsg(int, short, void *);
49 void dns_sig_handler(int, short, void *);
50 void dns_shutdown(void);
51 int host_dns(const char *, struct ypldap_addr_list *);
54 dns_sig_handler(int sig, short event, void *p)
62 fatalx("unexpected signal");
69 log_info("dns engine exiting");
74 ypldap_dns(int pipe_ntp[2], struct passwd *pw)
77 struct event ev_sigint;
78 struct event ev_sigterm;
79 struct event ev_sighup;
82 switch (pid = fork()) {
92 setproctitle("dns engine");
95 if (setgroups(1, &pw->pw_gid) ||
96 setresgid(pw->pw_gid, pw->pw_gid, pw->pw_gid) ||
97 setresuid(pw->pw_uid, pw->pw_uid, pw->pw_uid))
98 fatal("can't drop privileges");
102 signal_set(&ev_sigint, SIGINT, dns_sig_handler, NULL);
103 signal_set(&ev_sigterm, SIGTERM, dns_sig_handler, NULL);
104 signal_set(&ev_sighup, SIGHUP, dns_sig_handler, NULL);
105 signal_add(&ev_sigint, NULL);
106 signal_add(&ev_sigterm, NULL);
107 signal_add(&ev_sighup, NULL);
109 if ((env.sc_iev = calloc(1, sizeof(*env.sc_iev))) == NULL)
112 env.sc_iev->events = EV_READ;
113 env.sc_iev->data = &env;
114 imsg_init(&env.sc_iev->ibuf, pipe_ntp[1]);
115 env.sc_iev->handler = dns_dispatch_imsg;
116 event_set(&env.sc_iev->ev, env.sc_iev->ibuf.fd, env.sc_iev->events,
117 env.sc_iev->handler, &env);
118 event_add(&env.sc_iev->ev, NULL);
127 dns_dispatch_imsg(int fd, short events, void *p)
132 struct ypldap_addr_list hn = TAILQ_HEAD_INITIALIZER(hn);
133 struct ypldap_addr *h;
136 struct imsgev *iev = env->sc_iev;
137 struct imsgbuf *ibuf = &iev->ibuf;
140 if ((events & (EV_READ | EV_WRITE)) == 0)
141 fatalx("unknown event");
143 if (events & EV_READ) {
144 if ((n = imsg_read(ibuf)) == -1 && errno != EAGAIN)
145 fatal("imsg_read error");
149 if (events & EV_WRITE) {
150 if ((n = msgbuf_write(&ibuf->w)) == -1 && errno != EAGAIN)
151 fatal("msgbuf_write");
158 if ((n = imsg_get(ibuf, &imsg)) == -1)
159 fatal("client_dispatch_imsg: imsg_get error");
163 switch (imsg.hdr.type) {
166 if (imsg.hdr.len < 1 + IMSG_HEADER_SIZE)
167 fatalx("invalid IMSG_HOST_DNS received");
168 imsg.hdr.len -= 1 + IMSG_HEADER_SIZE;
169 if (name[imsg.hdr.len] != '\0' ||
170 strlen(name) != imsg.hdr.len)
171 fatalx("invalid IMSG_HOST_DNS received");
172 if ((cnt = host_dns(name, &hn)) == -1)
174 buf = imsg_create(ibuf, IMSG_HOST_DNS,
176 cnt * sizeof(struct sockaddr_storage));
180 while(!TAILQ_EMPTY(&hn)) {
181 h = TAILQ_FIRST(&hn);
182 TAILQ_REMOVE(&hn, h, next);
183 imsg_add(buf, &h->ss, sizeof(h->ss));
188 imsg_close(ibuf, buf);
200 /* this pipe is dead, so remove the event handler */
202 event_loopexit(NULL);
207 host_dns(const char *s, struct ypldap_addr_list *hn)
209 struct addrinfo hints, *res0, *res;
211 struct sockaddr_in *sa_in;
212 struct sockaddr_in6 *sa_in6;
213 struct ypldap_addr *h;
215 memset(&hints, 0, sizeof(hints));
216 hints.ai_family = PF_UNSPEC;
217 hints.ai_socktype = SOCK_DGRAM; /* DUMMY */
218 error = getaddrinfo(s, NULL, &hints, &res0);
219 if (error == EAI_AGAIN || error == EAI_NONAME)
222 log_warnx("could not parse \"%s\": %s", s,
223 gai_strerror(error));
227 for (res = res0; res && cnt < MAX_SERVERS_DNS; res = res->ai_next) {
228 if (res->ai_family != AF_INET &&
229 res->ai_family != AF_INET6)
231 if ((h = calloc(1, sizeof(struct ypldap_addr))) == NULL)
233 h->ss.ss_family = res->ai_family;
234 if (res->ai_family == AF_INET) {
235 sa_in = (struct sockaddr_in *)&h->ss;
236 sa_in->sin_len = sizeof(struct sockaddr_in);
237 sa_in->sin_addr.s_addr = ((struct sockaddr_in *)
238 res->ai_addr)->sin_addr.s_addr;
240 sa_in6 = (struct sockaddr_in6 *)&h->ss;
241 sa_in6->sin6_len = sizeof(struct sockaddr_in6);
242 memcpy(&sa_in6->sin6_addr, &((struct sockaddr_in6 *)
243 res->ai_addr)->sin6_addr, sizeof(struct in6_addr));
246 TAILQ_INSERT_HEAD(hn, h, next);