1 /* 2 * src/nf-monitor.c Monitor netfilter events 3 * 4 * This library is free software; you can redistribute it and/or 5 * modify it under the terms of the GNU Lesser General Public 6 * License as published by the Free Software Foundation version 2.1 7 * of the License. 8 * 9 * Copyright (c) 2003-2008 Thomas Graf <tgraf (at) suug.ch> 10 * Copyright (c) 2007 Philip Craig <philipc (at) snapgear.com> 11 * Copyright (c) 2007 Secure Computing Corporation 12 */ 13 14 #include <netlink/cli/utils.h> 15 #include <netlink/netfilter/nfnl.h> 16 17 static void obj_input(struct nl_object *obj, void *arg) 18 { 19 struct nl_dump_params dp = { 20 .dp_type = NL_DUMP_STATS, 21 .dp_fd = stdout, 22 .dp_dump_msgtype = 1, 23 }; 24 25 nl_object_dump(obj, &dp); 26 } 27 28 static int event_input(struct nl_msg *msg, void *arg) 29 { 30 if (nl_msg_parse(msg, &obj_input, NULL) < 0) 31 fprintf(stderr, "<<EVENT>> Unknown message type\n"); 32 33 /* Exit nl_recvmsgs_def() and return to the main select() */ 34 return NL_STOP; 35 } 36 37 int main(int argc, char *argv[]) 38 { 39 struct nl_sock *sock; 40 int err; 41 int i, idx; 42 43 static const struct { 44 enum nfnetlink_groups gr_id; 45 const char* gr_name; 46 } groups[] = { 47 { NFNLGRP_CONNTRACK_NEW, "ct-new" }, 48 { NFNLGRP_CONNTRACK_UPDATE, "ct-update" }, 49 { NFNLGRP_CONNTRACK_DESTROY, "ct-destroy" }, 50 { NFNLGRP_NONE, NULL } 51 }; 52 53 sock = nl_cli_alloc_socket(); 54 nl_socket_disable_seq_check(sock); 55 nl_socket_modify_cb(sock, NL_CB_VALID, NL_CB_CUSTOM, event_input, NULL); 56 57 if (argc > 1 && !strcasecmp(argv[1], "-h")) { 58 printf("Usage: nf-monitor [<groups>]\n"); 59 60 printf("Known groups:"); 61 for (i = 0; groups[i].gr_id != NFNLGRP_NONE; i++) 62 printf(" %s", groups[i].gr_name); 63 printf("\n"); 64 return 2; 65 } 66 67 nl_cli_connect(sock, NETLINK_NETFILTER); 68 69 for (idx = 1; argc > idx; idx++) { 70 for (i = 0; groups[i].gr_id != NFNLGRP_NONE; i++) { 71 if (strcmp(argv[idx], groups[i].gr_name)) 72 continue; 73 74 err = nl_socket_add_membership(sock, groups[i].gr_id); 75 if (err < 0) 76 nl_cli_fatal(err, 77 "Unable to add membership: %s", 78 nl_geterror(err)); 79 break; 80 } 81 82 if (groups[i].gr_id == NFNLGRP_NONE) 83 nl_cli_fatal(NLE_OBJ_NOTFOUND, "Unknown group: \"%s\"", 84 argv[idx]); 85 } 86 87 while (1) { 88 fd_set rfds; 89 int fd, retval; 90 91 fd = nl_socket_get_fd(sock); 92 93 FD_ZERO(&rfds); 94 FD_SET(fd, &rfds); 95 /* wait for an incoming message on the netlink socket */ 96 retval = select(fd+1, &rfds, NULL, NULL, NULL); 97 98 if (retval) { 99 /* FD_ISSET(fd, &rfds) will be true */ 100 nl_recvmsgs_default(sock); 101 } 102 } 103 104 return 0; 105 } 106
