1 /**
2 * Copyright 2017 Florian Forster
3 *
4 * Permission is hereby granted, free of charge, to any person obtaining a copy
5 * of this software and associated documentation files (the "Software"), to deal
6 * in the Software without restriction, including without limitation the rights
7 * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
8 * copies of the Software, and to permit persons to whom the Software is
9 * furnished to do so, subject to the following conditions:
10 *
11 * The above copyright notice and this permission notice shall be included in
12 * all copies or substantial portions of the Software.
13 *
14 * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
15 * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
16 * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
17 * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
18 * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
19 * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
20 * SOFTWARE.
21 *
22 * Authors:
23 * Florian octo Forster <octo at collectd.org>
24 **/
26 #include "config.h"
28 #if !defined(__GNUC__) || !__GNUC__
29 #define __attribute__(x) /**/
30 #endif
32 #include "collectd/lcc_features.h"
33 #include "collectd/network_parse.h" /* for lcc_network_parse_options_t */
34 #include "collectd/server.h"
36 #include <errno.h>
37 #include <net/if.h>
38 #include <netdb.h>
39 #include <netinet/in.h>
40 #include <string.h>
41 #include <sys/socket.h>
42 #include <sys/types.h>
43 #include <unistd.h>
45 #include <stdio.h>
46 #define DEBUG(...) printf(__VA_ARGS__)
48 static _Bool is_multicast(struct addrinfo const *ai) {
49 if (ai->ai_family == AF_INET) {
50 struct sockaddr_in *addr = (struct sockaddr_in *)ai->ai_addr;
51 return IN_MULTICAST(ntohl(addr->sin_addr.s_addr));
52 } else if (ai->ai_family == AF_INET6) {
53 struct sockaddr_in6 *addr = (struct sockaddr_in6 *)ai->ai_addr;
54 return IN6_IS_ADDR_MULTICAST(&addr->sin6_addr);
55 }
56 return 0;
57 }
59 static int server_multicast_join(lcc_listener_t *srv,
60 struct sockaddr_storage *group, int loop_back,
61 int ttl) {
62 if (group->ss_family == AF_INET) {
63 struct sockaddr_in *sa = (struct sockaddr_in *)group;
65 int status = setsockopt(srv->conn, IPPROTO_IP, IP_MULTICAST_LOOP,
66 &loop_back, sizeof(loop_back));
67 if (status == -1) {
68 DEBUG("setsockopt(IP_MULTICAST_LOOP, %d) = %d\n", loop_back, errno);
69 return errno;
70 }
72 status =
73 setsockopt(srv->conn, IPPROTO_IP, IP_MULTICAST_TTL, &ttl, sizeof(ttl));
74 if (status == -1)
75 return errno;
77 #if HAVE_STRUCT_IP_MREQN_IMR_IFINDEX
78 struct ip_mreqn mreq = {
79 .imr_address.s_addr = INADDR_ANY,
80 .imr_multiaddr.s_addr = sa->sin_addr.s_addr,
81 .imr_ifindex = if_nametoindex(srv->interface),
82 };
83 #else
84 struct ip_mreq mreq = {
85 .imr_multiaddr.s_addr = sa->sin_addr.s_addr,
86 };
87 #endif
88 status = setsockopt(srv->conn, IPPROTO_IP, IP_ADD_MEMBERSHIP, &mreq,
89 sizeof(mreq));
90 if (status == -1)
91 return errno;
92 } else if (group->ss_family == AF_INET6) {
93 struct sockaddr_in6 *sa = (struct sockaddr_in6 *)group;
95 int status = setsockopt(srv->conn, IPPROTO_IPV6, IPV6_MULTICAST_LOOP,
96 &loop_back, sizeof(loop_back));
97 if (status == -1)
98 return errno;
100 status = setsockopt(srv->conn, IPPROTO_IPV6, IPV6_MULTICAST_HOPS, &ttl,
101 sizeof(ttl));
102 if (status == -1)
103 return errno;
105 struct ipv6_mreq mreq6 = {
106 .ipv6mr_interface = if_nametoindex(srv->interface),
107 };
108 memmove(&mreq6.ipv6mr_multiaddr, &sa->sin6_addr, sizeof(struct in6_addr));
110 status = setsockopt(srv->conn, IPPROTO_IPV6, IPV6_JOIN_GROUP, &mreq6,
111 sizeof(mreq6));
112 if (status == -1)
113 return errno;
114 } else {
115 return EINVAL;
116 }
118 return 0;
119 }
121 static int server_bind_socket(lcc_listener_t *srv, struct addrinfo const *ai) {
122 /* allow multiple sockets to use the same PORT number */
123 if (setsockopt(srv->conn, SOL_SOCKET, SO_REUSEADDR, &(int){1}, sizeof(int)) ==
124 -1) {
125 return errno;
126 }
128 if (bind(srv->conn, ai->ai_addr, ai->ai_addrlen) == -1) {
129 return -1;
130 }
132 if (is_multicast(ai)) {
133 int status = server_multicast_join(srv, (void *)ai->ai_addr, /* loop = */ 1,
134 /* ttl = */ 16);
135 if (status != 0)
136 return status;
137 }
139 return 0;
140 }
142 static int server_open(lcc_listener_t *srv) {
143 struct addrinfo *res = NULL;
144 int status = getaddrinfo(srv->node ? srv->node : "::",
145 srv->service ? srv->service : LCC_DEFAULT_PORT,
146 &(struct addrinfo){
147 .ai_flags = AI_ADDRCONFIG,
148 .ai_family = AF_UNSPEC,
149 .ai_socktype = SOCK_DGRAM,
150 },
151 &res);
152 if (status != 0)
153 return status;
155 for (struct addrinfo *ai = res; ai != NULL; ai = ai->ai_next) {
156 srv->conn = socket(ai->ai_family, ai->ai_socktype, 0);
157 if (srv->conn == -1)
158 continue;
160 status = server_bind_socket(srv, ai);
161 if (status != 0) {
162 close(srv->conn);
163 srv->conn = -1;
164 continue;
165 }
167 break;
168 }
170 freeaddrinfo(res);
172 if (srv->conn >= 0)
173 return 0;
174 return status != 0 ? status : -1;
175 }
177 int lcc_listen_and_write(lcc_listener_t srv) {
178 _Bool close_socket = 0;
180 if (srv.conn < 0) {
181 int status = server_open(&srv);
182 if (status != 0)
183 return status;
184 close_socket = 1;
185 }
187 if (srv.buffer_size == 0)
188 srv.buffer_size = LCC_NETWORK_BUFFER_SIZE;
190 if (srv.parser == NULL)
191 srv.parser = lcc_network_parse;
193 int ret = 0;
194 while (42) {
195 char buffer[srv.buffer_size];
196 ssize_t len = recv(srv.conn, buffer, sizeof(buffer), /* flags = */ 0);
197 if (len == -1) {
198 ret = errno;
199 break;
200 } else if (len == 0) {
201 break;
202 }
204 (void)srv.parser(buffer, (size_t)len, srv.parse_options);
205 }
207 if (close_socket) {
208 close(srv.conn);
209 srv.conn = -1;
210 }
212 return ret;
213 }