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 = 15;
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 nlmsghdr * n,void * arg)48 static int dump_msg(const struct sockaddr_nl *who, struct nlmsghdr *n,
49 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
usage(void)59 void usage(void)
60 {
61 fprintf(stderr, "Usage: rtmon file FILE [ all | LISTofOBJECTS]\n");
62 fprintf(stderr, "LISTofOBJECTS := [ link ] [ address ] [ route ]\n");
63 exit(-1);
64 }
65
66 int
main(int argc,char ** argv)67 main(int argc, char **argv)
68 {
69 FILE *fp;
70 struct rtnl_handle rth;
71 int family = AF_UNSPEC;
72 unsigned groups = ~0U;
73 int llink = 0;
74 int laddr = 0;
75 int lroute = 0;
76 char *file = NULL;
77
78 while (argc > 1) {
79 if (matches(argv[1], "-family") == 0) {
80 argc--;
81 argv++;
82 if (argc <= 1)
83 usage();
84 if (strcmp(argv[1], "inet") == 0)
85 family = AF_INET;
86 else if (strcmp(argv[1], "inet6") == 0)
87 family = AF_INET6;
88 else if (strcmp(argv[1], "link") == 0)
89 family = AF_INET6;
90 else if (strcmp(argv[1], "help") == 0)
91 usage();
92 else {
93 fprintf(stderr, "Protocol ID \"%s\" is unknown, try \"rtmon help\".\n", argv[1]);
94 exit(-1);
95 }
96 } else if (strcmp(argv[1], "-4") == 0) {
97 family = AF_INET;
98 } else if (strcmp(argv[1], "-6") == 0) {
99 family = AF_INET6;
100 } else if (strcmp(argv[1], "-0") == 0) {
101 family = AF_PACKET;
102 } else if (matches(argv[1], "-Version") == 0) {
103 printf("rtmon utility, iproute2-ss%s\n", SNAPSHOT);
104 exit(0);
105 } else if (matches(argv[1], "file") == 0) {
106 argc--;
107 argv++;
108 if (argc <= 1)
109 usage();
110 file = argv[1];
111 } else if (matches(argv[1], "link") == 0) {
112 llink=1;
113 groups = 0;
114 } else if (matches(argv[1], "address") == 0) {
115 laddr=1;
116 groups = 0;
117 } else if (matches(argv[1], "route") == 0) {
118 lroute=1;
119 groups = 0;
120 } else if (strcmp(argv[1], "all") == 0) {
121 groups = ~0U;
122 } else if (matches(argv[1], "help") == 0) {
123 usage();
124 } else {
125 fprintf(stderr, "Argument \"%s\" is unknown, try \"rtmon help\".\n", argv[1]);
126 exit(-1);
127 }
128 argc--; argv++;
129 }
130
131 if (file == NULL) {
132 fprintf(stderr, "Not enough information: argument \"file\" is required\n");
133 exit(-1);
134 }
135 if (llink)
136 groups |= nl_mgrp(RTNLGRP_LINK);
137 if (laddr) {
138 if (!family || family == AF_INET)
139 groups |= nl_mgrp(RTNLGRP_IPV4_IFADDR);
140 if (!family || family == AF_INET6)
141 groups |= nl_mgrp(RTNLGRP_IPV6_IFADDR);
142 }
143 if (lroute) {
144 if (!family || family == AF_INET)
145 groups |= nl_mgrp(RTNLGRP_IPV4_ROUTE);
146 if (!family || family == AF_INET6)
147 groups |= nl_mgrp(RTNLGRP_IPV6_ROUTE);
148 }
149
150 fp = fopen(file, "w");
151 if (fp == NULL) {
152 perror("Cannot fopen");
153 exit(-1);
154 }
155
156 if (rtnl_open(&rth, groups) < 0)
157 exit(1);
158
159 if (rtnl_wilddump_request(&rth, AF_UNSPEC, RTM_GETLINK) < 0) {
160 perror("Cannot send dump request");
161 exit(1);
162 }
163
164 write_stamp(fp);
165
166 if (rtnl_dump_filter(&rth, dump_msg, fp) < 0) {
167 fprintf(stderr, "Dump terminated\n");
168 return 1;
169 }
170
171 init_phase = 0;
172
173 if (rtnl_listen(&rth, dump_msg, (void*)fp) < 0)
174 exit(2);
175
176 exit(0);
177 }
178