1 /*
2 * rtmon.c RTnetlink listener.
3 *
4 * This program is free software; you can redistribute it and/or
5 * modify it under the terms of the GNU General Public License
6 * as published by the Free Software Foundation; either version
7 * 2 of the License, or (at your option) any later version.
8 *
9 * Authors: Alexey Kuznetsov, <kuznet@ms2.inr.ac.ru>
10 *
11 */
12
13 #include <stdio.h>
14 #include <stdlib.h>
15 #include <unistd.h>
16 #include <syslog.h>
17 #include <fcntl.h>
18 #include <sys/socket.h>
19 #include <sys/time.h>
20 #include <netinet/in.h>
21 #include <string.h>
22
23 #include "SNAPSHOT.h"
24
25 #include "utils.h"
26 #include "libnetlink.h"
27
28 int resolve_hosts = 0;
29 static int init_phase = 1;
30
write_stamp(FILE * fp)31 static void write_stamp(FILE *fp)
32 {
33 char buf[128];
34 struct nlmsghdr *n1 = (void*)buf;
35 struct timeval tv;
36
37 n1->nlmsg_type = NLMSG_TSTAMP;
38 n1->nlmsg_flags = 0;
39 n1->nlmsg_seq = 0;
40 n1->nlmsg_pid = 0;
41 n1->nlmsg_len = NLMSG_LENGTH(4*2);
42 gettimeofday(&tv, NULL);
43 ((__u32*)NLMSG_DATA(n1))[0] = tv.tv_sec;
44 ((__u32*)NLMSG_DATA(n1))[1] = tv.tv_usec;
45 fwrite((void*)n1, 1, NLMSG_ALIGN(n1->nlmsg_len), fp);
46 }
47
dump_msg(const struct sockaddr_nl * who,struct rtnl_ctrl_data * ctrl,struct nlmsghdr * n,void * arg)48 static int dump_msg(const struct sockaddr_nl *who, struct rtnl_ctrl_data *ctrl,
49 struct nlmsghdr *n, void *arg)
50 {
51 FILE *fp = (FILE*)arg;
52 if (!init_phase)
53 write_stamp(fp);
54 fwrite((void*)n, 1, NLMSG_ALIGN(n->nlmsg_len), fp);
55 fflush(fp);
56 return 0;
57 }
58
dump_msg2(const struct sockaddr_nl * who,struct nlmsghdr * n,void * arg)59 static int dump_msg2(const struct sockaddr_nl *who,
60 struct nlmsghdr *n, void *arg)
61 {
62 return dump_msg(who, NULL, n, arg);
63 }
64
usage(void)65 static void usage(void)
66 {
67 fprintf(stderr, "Usage: rtmon file FILE [ all | LISTofOBJECTS]\n");
68 fprintf(stderr, "LISTofOBJECTS := [ link ] [ address ] [ route ]\n");
69 exit(-1);
70 }
71
72 int
main(int argc,char ** argv)73 main(int argc, char **argv)
74 {
75 FILE *fp;
76 struct rtnl_handle rth;
77 int family = AF_UNSPEC;
78 unsigned groups = ~0U;
79 int llink = 0;
80 int laddr = 0;
81 int lroute = 0;
82 char *file = NULL;
83
84 while (argc > 1) {
85 if (matches(argv[1], "-family") == 0) {
86 argc--;
87 argv++;
88 if (argc <= 1)
89 usage();
90 if (strcmp(argv[1], "inet") == 0)
91 family = AF_INET;
92 else if (strcmp(argv[1], "inet6") == 0)
93 family = AF_INET6;
94 else if (strcmp(argv[1], "link") == 0)
95 family = AF_INET6;
96 else if (strcmp(argv[1], "help") == 0)
97 usage();
98 else {
99 fprintf(stderr, "Protocol ID \"%s\" is unknown, try \"rtmon help\".\n", argv[1]);
100 exit(-1);
101 }
102 } else if (strcmp(argv[1], "-4") == 0) {
103 family = AF_INET;
104 } else if (strcmp(argv[1], "-6") == 0) {
105 family = AF_INET6;
106 } else if (strcmp(argv[1], "-0") == 0) {
107 family = AF_PACKET;
108 } else if (matches(argv[1], "-Version") == 0) {
109 printf("rtmon utility, iproute2-ss%s\n", SNAPSHOT);
110 exit(0);
111 } else if (matches(argv[1], "file") == 0) {
112 argc--;
113 argv++;
114 if (argc <= 1)
115 usage();
116 file = argv[1];
117 } else if (matches(argv[1], "link") == 0) {
118 llink=1;
119 groups = 0;
120 } else if (matches(argv[1], "address") == 0) {
121 laddr=1;
122 groups = 0;
123 } else if (matches(argv[1], "route") == 0) {
124 lroute=1;
125 groups = 0;
126 } else if (strcmp(argv[1], "all") == 0) {
127 groups = ~0U;
128 } else if (matches(argv[1], "help") == 0) {
129 usage();
130 } else {
131 fprintf(stderr, "Argument \"%s\" is unknown, try \"rtmon help\".\n", argv[1]);
132 exit(-1);
133 }
134 argc--; argv++;
135 }
136
137 if (file == NULL) {
138 fprintf(stderr, "Not enough information: argument \"file\" is required\n");
139 exit(-1);
140 }
141 if (llink)
142 groups |= nl_mgrp(RTNLGRP_LINK);
143 if (laddr) {
144 if (!family || family == AF_INET)
145 groups |= nl_mgrp(RTNLGRP_IPV4_IFADDR);
146 if (!family || family == AF_INET6)
147 groups |= nl_mgrp(RTNLGRP_IPV6_IFADDR);
148 }
149 if (lroute) {
150 if (!family || family == AF_INET)
151 groups |= nl_mgrp(RTNLGRP_IPV4_ROUTE);
152 if (!family || family == AF_INET6)
153 groups |= nl_mgrp(RTNLGRP_IPV6_ROUTE);
154 }
155
156 fp = fopen(file, "w");
157 if (fp == NULL) {
158 perror("Cannot fopen");
159 exit(-1);
160 }
161
162 if (rtnl_open(&rth, groups) < 0)
163 exit(1);
164
165 if (rtnl_wilddump_request(&rth, AF_UNSPEC, RTM_GETLINK) < 0) {
166 perror("Cannot send dump request");
167 exit(1);
168 }
169
170 write_stamp(fp);
171
172 if (rtnl_dump_filter(&rth, dump_msg2, fp) < 0) {
173 fprintf(stderr, "Dump terminated\n");
174 return 1;
175 }
176
177 init_phase = 0;
178
179 if (rtnl_listen(&rth, dump_msg, (void*)fp) < 0)
180 exit(2);
181
182 exit(0);
183 }
184