1 #ifndef lint 2 static char sccsid[] = "@(#)main.c 4.1 11/02/82"; 3 #endif 4 5 /* 6 * Routing Table Management Daemon 7 */ 8 #include "router.h" 9 #include <sys/ioctl.h> 10 #include <net/if.h> 11 #include <errno.h> 12 #include <nlist.h> 13 #include <signal.h> 14 #include <time.h> 15 16 int supplier = -1; /* process should supply updates */ 17 18 struct rip *msg = (struct rip *)packet; 19 20 main(argc, argv) 21 int argc; 22 char *argv[]; 23 { 24 int cc; 25 struct sockaddr from; 26 27 argv0 = argv; 28 #ifndef DEBUG 29 if (fork()) 30 exit(0); 31 for (cc = 0; cc < 10; cc++) 32 (void) close(cc); 33 (void) open("/", 0); 34 (void) dup2(0, 1); 35 (void) dup2(0, 2); 36 { int t = open("/dev/tty", 2); 37 if (t >= 0) { 38 ioctl(t, TIOCNOTTY, (char *)0); 39 (void) close(t); 40 } 41 } 42 #endif 43 if (tracing) 44 traceon("/etc/routerlog"); 45 46 /* 47 * We use two sockets. One for which outgoing 48 * packets are routed and for which they're not. 49 * The latter allows us to delete routing table 50 * entries in the kernel for network interfaces 51 * attached to our host which we believe are down 52 * while still polling it to see when/if it comes 53 * back up. With the new ipc interface we'll be 54 * able to specify ``don't route'' as an option 55 * to send, but until then we utilize a second port. 56 */ 57 sp = getservbyname("router", "udp"); 58 if (sp == 0) { 59 fprintf(stderr, "routed: udp/router: unknown service\n"); 60 exit(1); 61 } 62 routingaddr.sin_family = AF_INET; 63 routingaddr.sin_port = htons(sp->s_port); 64 noroutingaddr.sin_family = AF_INET; 65 noroutingaddr.sin_port = htons(sp->s_port + 1); 66 again: 67 s = socket(SOCK_DGRAM, 0, &routingaddr, 0); 68 if (s < 0) { 69 perror("socket"); 70 sleep(30); 71 goto again; 72 } 73 again2: 74 snoroute = socket(SOCK_DGRAM, 0, &noroutingaddr, SO_DONTROUTE); 75 if (snoroute < 0) { 76 perror("socket"); 77 sleep(30); 78 goto again2; 79 } 80 argv++, argc--; 81 while (argc > 0 && **argv == '-') { 82 if (!strcmp(*argv, "-s") == 0) { 83 supplier = 1; 84 argv++, argc--; 85 continue; 86 } 87 if (!strcmp(*argv, "-q") == 0) { 88 supplier = 0; 89 argv++, argc--; 90 continue; 91 } 92 goto usage; 93 } 94 if (argc > 0) { 95 usage: 96 fprintf(stderr, "usage: routed [ -s ] [ -q ]\n"); 97 exit(1); 98 } 99 /* 100 * Collect an initial view of the world by 101 * snooping in the kernel and the gateway kludge 102 * file. Then, send a request packet on all 103 * directly connected networks to find out what 104 * everyone else thinks. 105 */ 106 rtinit(); 107 gwkludge(); 108 ifinit(); 109 if (supplier < 0) 110 supplier = 0; 111 msg->rip_cmd = RIPCMD_REQUEST; 112 msg->rip_nets[0].rip_dst.sa_family = AF_UNSPEC; 113 msg->rip_nets[0].rip_metric = HOPCNT_INFINITY; 114 toall(sendmsg); 115 sigset(SIGALRM, timer); 116 timer(); 117 118 #define INFINITY 1000000 119 for (;;) { 120 int ibits; 121 register int n; 122 123 ibits = (1 << s) | (1 << snoroute); 124 n = select(32, &ibits, 0, INFINITY); 125 if (n < 0) 126 continue; 127 if (ibits & (1 << s)) 128 process(s); 129 if (ibits & (1 << snoroute)) 130 process(snoroute); 131 } 132 } 133 134 process(fd) 135 int fd; 136 { 137 register int cc; 138 struct sockaddr from; 139 140 cc = receive(fd, &from, packet, sizeof (packet)); 141 if (cc <= 0) { 142 if (cc < 0 && errno != EINTR) 143 perror("receive"); 144 return; 145 } 146 sighold(SIGALRM); 147 rip_input(&from, cc); 148 sigrelse(SIGALRM); 149 } 150