+++ /dev/null
-/*
-rarpd.c
-
-Created: Nov 12, 1992 by Philip Homburg
-
-Changed: May 13, 1995 by Kees J. Bot
- Rewrite to handle multiple ethernets.
-
-Changed: Jul 18, 1995 by Kees J. Bot
- Do RARP requests (formerly inet's job)
-
-Changed: Dec 14, 1996 by Kees J. Bot
- Query the netmask
-
-Changed: Dec 11, 2000 by Kees J. Bot
- Dressed down to be only a RARP server, giving the floor to DHCP
-*/
-
-#include <sys/types.h>
-#include <sys/ioctl.h>
-#include <errno.h>
-#include <fcntl.h>
-#include <stdio.h>
-#include <stdlib.h>
-#include <signal.h>
-#include <string.h>
-#include <unistd.h>
-#include <sys/asynchio.h>
-#include <net/hton.h>
-#include <net/gen/socket.h>
-#include <netdb.h>
-#include <net/gen/in.h>
-#include <net/gen/inet.h>
-#include <net/gen/ether.h>
-#include <net/gen/eth_io.h>
-#include <net/gen/if_ether.h>
-#include <net/gen/ip_io.h>
-#include <arpa/nameser.h>
-#include <arpa/inet.h>
-
-#define MAX_RARP_RETRIES 5
-#define RARP_TIMEOUT 5
-
-#undef HTONS
-#define HTONS htons
-
-typedef struct rarp46
-{
- ether_addr_t a46_dstaddr;
- ether_addr_t a46_srcaddr;
- ether_type_t a46_ethtype;
- u16_t a46_hdr, a46_pro;
- u8_t a46_hln, a46_pln;
- u16_t a46_op;
- ether_addr_t a46_sha;
- u8_t a46_spa[4];
- ether_addr_t a46_tha;
- u8_t a46_tpa[4];
- char a46_padding[ETH_MIN_PACK_SIZE - (4*6 + 2*4 + 4*2 + 2*1)];
-} rarp46_t;
-
-#define ETH_RARP_PROTO 0x8035
-
-#define RARP_ETHERNET 1
-
-#define RARP_REQUEST 3
-#define RARP_REPLY 4
-
-static char *program;
-static unsigned debug;
-
-#define between(a, c, z) ((unsigned) (c) - (a) <= (unsigned) (z) - (a))
-
-static void report(const char *label)
-{
- fprintf(stderr, "%s: %s: %s\n", program, label, strerror(errno));
-}
-
-static void fatal(const char *label)
-{
- report(label);
- exit(1);
-}
-
-static void *allocate(size_t size)
-{
- void *mem;
-
- if ((mem= malloc(size)) == NULL) fatal("Can't allocate memory");
- return mem;
-}
-
-static char *ethdev(int n)
-{
- static char an_ethdev[]= "/dev/ethNNN";
-
- sprintf(an_ethdev + sizeof(an_ethdev)-4, "%d", n);
- return an_ethdev;
-}
-
-static char *ipdev(int n)
-{
- static char an_ipdev[]= "/dev/ipNNN";
-
- sprintf(an_ipdev + sizeof(an_ipdev)-4, "%d", n);
- return an_ipdev;
-}
-
-typedef struct ethernet {
- int n; /* Network number. */
- int eth_fd; /* Open low level ethernet device. */
- ether_addr_t eth_addr; /* Ethernet address of this net. */
- char packet[ETH_MAX_PACK_SIZE]; /* Incoming packet. */
- ipaddr_t ip_addr; /* IP address of this net. */
- ipaddr_t ip_mask; /* Associated netmask. */
-} ethernet_t;
-
-static ethernet_t *ethernets;
-
-static void onsig(int sig)
-{
- switch (sig) {
- case SIGUSR1: debug++; break;
- case SIGUSR2: debug= 0; break;
- }
-}
-
-static void rarp_reply(ethernet_t *ep, char *hostname, ipaddr_t ip_addr,
- ether_addr_t eth_addr)
-{
- rarp46_t rarp46;
-
- /* Construct a RARP reply packet and send it. */
- rarp46.a46_dstaddr= eth_addr;
- rarp46.a46_hdr= HTONS(RARP_ETHERNET);
- rarp46.a46_pro= HTONS(ETH_IP_PROTO);
- rarp46.a46_hln= 6;
- rarp46.a46_pln= 4;
- rarp46.a46_op= HTONS(RARP_REPLY);
- rarp46.a46_sha= ep->eth_addr;
- memcpy(rarp46.a46_spa, &ep->ip_addr, sizeof(ipaddr_t));
- rarp46.a46_tha= eth_addr;
- memcpy(rarp46.a46_tpa, &ip_addr, sizeof(ipaddr_t));
-
- if (debug >= 1) {
- printf("%s: Replying %s (%s) to %s\n",
- ethdev(ep->n), inet_ntoa(*(struct in_addr *)&ip_addr), hostname,
- ether_ntoa(ð_addr));
- }
- (void) write(ep->eth_fd, &rarp46, sizeof(rarp46));
-}
-
-static int addhostname(char *addname, char *hostname, int n)
-{
- /* Create an additional hostname for a given hostname by adding "-n" to
- * the first part. E.g. given "wombat.cs.vu.nl" and n=2 return
- * "wombat-2.cs.vu.nl". This is useful for VU practical work where
- * people get a few extra ethernet addresses on a machine and are asked
- * to build a TCP/IP stack on it.
- */
- char *dot;
-
- if (strlen(hostname) + 4 >= 1024) return 0;
- if ((dot= strchr(hostname, '.')) == NULL) dot= strchr(hostname, 0);
- sprintf(addname, "%.*s-%d%s", (dot - hostname), hostname, n, dot);
- return 1;
-}
-
-static void usage(void)
-{
- fprintf(stderr, "Usage: %s [-d[level]] network-name ...\n", program);
- exit(1);
-}
-
-static int ifname2n(const char *name)
-{
- /* Translate an interface name, ip0, ip1, etc, to a number. */
- const char *np;
- char *end;
- unsigned long n;
-
- np= name;
- if (*np++ != 'i' || *np++ != 'p') usage();
- n= strtoul(np, &end, 10);
- if (end == np || *end != 0) usage();
- if (n >= 1000) {
- fprintf(stderr, "%s: Network number of \"%s\" is a bit large\n",
- program, name);
- exit(1);
- }
- return n;
-}
-
-int main(int argc, char **argv)
-{
- int i;
- ethernet_t *ep;
- nwio_ethopt_t ethopt;
- nwio_ethstat_t ethstat;
- char hostname[1024];
- struct hostent *hostent;
- struct sigaction sa;
- nwio_ipconf_t ipconf;
- asynchio_t asyn;
- ssize_t n;
- ipaddr_t ip_addr;
- rarp46_t rarp46;
- int fd;
- int n_eths;
-
- program= argv[0];
- asyn_init(&asyn);
-
- debug= 0;
- i= 1;
- while (i < argc && argv[i][0] == '-') {
- char *opt= argv[i++]+1;
-
- if (opt[0] == '-' && opt[1] == 0) break; /* -- */
-
- while (*opt != 0) switch (*opt++) {
- case 'd':
- debug= 1;
- if (between('0', *opt, '9')) debug= strtoul(opt, &opt, 10);
- break;
- default:
- usage();
- }
- }
-
- if ((n_eths= (argc - i)) == 0) usage();
-
-#if __minix_vmd
- /* Minix-vmd can handle all nets at once using async I/O. */
- ethernets= allocate(n_eths * sizeof(ethernets[0]));
- for (i= 0; i < n_eths; i++) {
- ethernets[i].n= ifname2n(argv[argc - n_eths + i]);
- }
-#else
- /* Minix forks n-1 times to handle each net in a process each. */
- for (i= 0; i < n_eths; i++) {
- if (i+1 < n_eths) {
- switch (fork()) {
- case -1: fatal("fork()");
- case 0: break;
- default: continue;
- }
- }
- ethernets= allocate(1 * sizeof(ethernets[0]));
- ethernets[0].n= ifname2n(argv[argc - n_eths + i]);
- }
- n_eths= 1;
-#endif
-
- sa.sa_handler= onsig;
- sigemptyset(&sa.sa_mask);
- sa.sa_flags= 0;
- sigaction(SIGUSR1, &sa, NULL);
- sigaction(SIGUSR2, &sa, NULL);
-
- for (i= 0; i < n_eths; i++) {
- ep= ðernets[i];
- if ((ep->eth_fd= open(ethdev(ep->n), O_RDWR)) < 0) fatal(ethdev(ep->n));
-
- if (ioctl(ep->eth_fd, NWIOGETHSTAT, ðstat) < 0) {
- fprintf(stderr, "%s: %s: Unable to get eth statistics: %s\n",
- program, ethdev(ep->n), strerror(errno));
- exit(1);
- }
- ep->eth_addr= ethstat.nwes_addr;
- if (debug >= 1) {
- printf("%s: Ethernet address is %s\n",
- ethdev(ep->n), ether_ntoa(&ep->eth_addr));
- }
-
- ethopt.nweo_flags= NWEO_COPY | NWEO_EN_LOC | NWEO_EN_BROAD |
- NWEO_TYPESPEC;
- ethopt.nweo_type= HTONS(ETH_RARP_PROTO);
-
- if (ioctl(ep->eth_fd, NWIOSETHOPT, ðopt) < 0) {
- fprintf(stderr, "%s: %s: Unable to set eth options: %s\n",
- program, ethdev(ep->n), strerror(errno));
- exit(1);
- }
-
- /* What are my address and netmask? */
- if ((fd= open(ipdev(ep->n), O_RDWR)) < 0) fatal(ipdev(ep->n));
- if (ioctl(fd, NWIOGIPCONF, &ipconf) < 0) fatal(ipdev(ep->n));
-
- ep->ip_addr= ipconf.nwic_ipaddr;
- ep->ip_mask= ipconf.nwic_netmask;
- close(fd);
- if (debug >= 1) {
- printf("%s: IP address is %s / ",
- ipdev(ep->n), inet_ntoa(*(struct in_addr *)&ep->ip_addr));
- printf("%s\n", inet_ntoa(*(struct in_addr *)&ep->ip_mask));
- }
- }
-
- /* Wait for RARP requests, reply, repeat. */
- for(;;) {
- fflush(NULL);
-
- /* Wait for a RARP request. */
- for (i= 0; i < n_eths; i++) {
- ep= ðernets[i];
-
- n= asyn_read(&asyn, ep->eth_fd, ep->packet, sizeof(ep->packet));
- if (n != -1) break;
- if (errno != EINPROGRESS) {
- report(ethdev(ep->n));
- sleep(10);
- }
- }
-
- /* RARP request? */
- if (i < n_eths
- && n >= sizeof(rarp46)
- && (memcpy(&rarp46, ep->packet, sizeof(rarp46)), 1)
- && rarp46.a46_hdr == HTONS(RARP_ETHERNET)
- && rarp46.a46_pro == HTONS(ETH_IP_PROTO)
- && rarp46.a46_hln == 6
- && rarp46.a46_pln == 4
- && rarp46.a46_op == HTONS(RARP_REQUEST)
- ) {
- if ((ether_ntohost(hostname, &rarp46.a46_tha) == 0
- || (rarp46.a46_tha.ea_addr[0] == 'v'
- && (memcpy(&ip_addr, rarp46.a46_tha.ea_addr+2, 4), 1)
- && (hostent= gethostbyaddr((char*) &ip_addr,
- 4, AF_INET)) != NULL
- && addhostname(hostname, hostent->h_name,
- rarp46.a46_tha.ea_addr[1])))
- && (hostent= gethostbyname(hostname)) != NULL
- && hostent->h_addrtype == AF_INET
- ) {
- /* Host is found in the ethers file and the DNS, or the
- * ethernet address denotes a special additional address
- * used for implementing a TCP/IP stack in user space.
- */
- for (i= 0; hostent->h_addr_list[i] != NULL; i++) {
- memcpy(&ip_addr, hostent->h_addr_list[i], sizeof(ipaddr_t));
-
- /* Check if the address is on this network. */
- if (((ip_addr ^ ep->ip_addr) & ep->ip_mask) == 0) break;
- }
-
- if (hostent->h_addr_list[i] != NULL) {
- rarp_reply(ep, hostname, ip_addr, rarp46.a46_tha);
- } else {
- if (debug >= 2) {
- printf("%s: Host '%s' (%s) is on the wrong net\n",
- ethdev(ep->n),
- hostname, ether_ntoa(&rarp46.a46_tha));
- }
- }
- } else {
- if (debug >= 2) {
- printf("%s: RARP request from unknown host '%s'\n",
- ethdev(ep->n), ether_ntoa(&rarp46.a46_tha));
- }
- }
- }
-
- /* Wait for another request. */
- if (asyn_wait(&asyn, 0, NULL) < 0) {
- report("asyn_wait()");
- sleep(10);
- }
- }
-}
