Annotation of sys/lib/libsa/net.c, Revision 1.1
1.1 ! nbrk 1: /* $OpenBSD: net.c,v 1.13 2003/08/11 06:23:09 deraadt Exp $ */
! 2: /* $NetBSD: net.c,v 1.14 1996/10/13 02:29:02 christos Exp $ */
! 3:
! 4: /*
! 5: * Copyright (c) 1992 Regents of the University of California.
! 6: * All rights reserved.
! 7: *
! 8: * This software was developed by the Computer Systems Engineering group
! 9: * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
! 10: * contributed to Berkeley.
! 11: *
! 12: * Redistribution and use in source and binary forms, with or without
! 13: * modification, are permitted provided that the following conditions
! 14: * are met:
! 15: * 1. Redistributions of source code must retain the above copyright
! 16: * notice, this list of conditions and the following disclaimer.
! 17: * 2. Redistributions in binary form must reproduce the above copyright
! 18: * notice, this list of conditions and the following disclaimer in the
! 19: * documentation and/or other materials provided with the distribution.
! 20: * 3. All advertising materials mentioning features or use of this software
! 21: * must display the following acknowledgement:
! 22: * This product includes software developed by the University of
! 23: * California, Lawrence Berkeley Laboratory and its contributors.
! 24: * 4. Neither the name of the University nor the names of its contributors
! 25: * may be used to endorse or promote products derived from this software
! 26: * without specific prior written permission.
! 27: *
! 28: * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
! 29: * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
! 30: * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
! 31: * ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
! 32: * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
! 33: * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
! 34: * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
! 35: * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
! 36: * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
! 37: * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
! 38: * SUCH DAMAGE.
! 39: *
! 40: * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp (LBL)
! 41: */
! 42:
! 43: #include <sys/param.h>
! 44: #include <sys/socket.h>
! 45:
! 46: #include <net/if.h>
! 47: #include <netinet/in.h>
! 48:
! 49: #include <netinet/in.h>
! 50: #include <netinet/if_ether.h>
! 51: #include <netinet/in_systm.h>
! 52: #include <netinet/ip.h>
! 53: #include <netinet/ip_var.h>
! 54: #include <netinet/udp.h>
! 55: #include <netinet/udp_var.h>
! 56:
! 57: #include "stand.h"
! 58: #include "net.h"
! 59:
! 60: /* Caller must leave room for ethernet, ip and udp headers in front!! */
! 61: ssize_t
! 62: sendudp(struct iodesc *d, void *pkt, size_t len)
! 63: {
! 64: ssize_t cc;
! 65: struct ip *ip;
! 66: struct udpiphdr *ui;
! 67: struct udphdr *uh;
! 68: u_char *ea;
! 69: struct ip tip;
! 70:
! 71: #ifdef NET_DEBUG
! 72: if (debug) {
! 73: printf("sendudp: d=%x called.\n", (u_int)d);
! 74: if (d) {
! 75: printf("saddr: %s:%d",
! 76: inet_ntoa(d->myip), ntohs(d->myport));
! 77: printf(" daddr: %s:%d\n",
! 78: inet_ntoa(d->destip), ntohs(d->destport));
! 79: }
! 80: }
! 81: #endif
! 82:
! 83: uh = (struct udphdr *)pkt - 1;
! 84: ip = (struct ip *)uh - 1;
! 85: len += sizeof(*ip) + sizeof(*uh);
! 86:
! 87: bzero(ip, sizeof(*ip) + sizeof(*uh));
! 88:
! 89: ip->ip_v = IPVERSION; /* half-char */
! 90: ip->ip_hl = sizeof(*ip) >> 2; /* half-char */
! 91: ip->ip_len = htons(len);
! 92: ip->ip_p = IPPROTO_UDP; /* char */
! 93: ip->ip_ttl = IP_TTL; /* char */
! 94: ip->ip_src = d->myip;
! 95: ip->ip_dst = d->destip;
! 96: ip->ip_sum = in_cksum(ip, sizeof(*ip)); /* short, but special */
! 97:
! 98: uh->uh_sport = d->myport;
! 99: uh->uh_dport = d->destport;
! 100: uh->uh_ulen = htons(len - sizeof(*ip));
! 101:
! 102: /* Calculate checksum (must save and restore ip header) */
! 103: tip = *ip;
! 104: ui = (struct udpiphdr *)ip;
! 105: bzero(ui->ui_x1, sizeof(ui->ui_x1));
! 106: ui->ui_len = uh->uh_ulen;
! 107: uh->uh_sum = in_cksum(ui, len);
! 108: *ip = tip;
! 109:
! 110: if (ip->ip_dst.s_addr == INADDR_BROADCAST || ip->ip_src.s_addr == 0 ||
! 111: netmask == 0 || SAMENET(ip->ip_src, ip->ip_dst, netmask))
! 112: ea = arpwhohas(d, ip->ip_dst);
! 113: else
! 114: ea = arpwhohas(d, gateip);
! 115:
! 116: cc = sendether(d, ip, len, ea, ETHERTYPE_IP);
! 117: if (cc < 0)
! 118: return (-1);
! 119: if ((size_t)cc != len)
! 120: panic("sendudp: bad write (%d != %d)", cc, len);
! 121: return (cc - (sizeof(*ip) + sizeof(*uh)));
! 122: }
! 123:
! 124: /*
! 125: * Receive a UDP packet and validate it is for us.
! 126: * Caller leaves room for the headers (Ether, IP, UDP)
! 127: */
! 128: ssize_t
! 129: readudp(struct iodesc *d, void *pkt, size_t len, time_t tleft)
! 130: {
! 131: ssize_t n;
! 132: size_t hlen;
! 133: struct ip *ip;
! 134: struct udphdr *uh;
! 135: struct udpiphdr *ui;
! 136: struct ip tip;
! 137: u_int16_t etype; /* host order */
! 138:
! 139: #ifdef NET_DEBUG
! 140: if (debug)
! 141: printf("readudp: called\n");
! 142: #endif
! 143:
! 144: uh = (struct udphdr *)pkt - 1;
! 145: ip = (struct ip *)uh - 1;
! 146:
! 147: n = readether(d, ip, len + sizeof(*ip) + sizeof(*uh), tleft, &etype);
! 148: if (n < 0 || (size_t)n < sizeof(*ip) + sizeof(*uh))
! 149: return -1;
! 150:
! 151: /* Ethernet address checks now in readether() */
! 152:
! 153: /* Need to respond to ARP requests. */
! 154: if (etype == ETHERTYPE_ARP) {
! 155: struct arphdr *ah = (void *)ip;
! 156: if (ah->ar_op == htons(ARPOP_REQUEST)) {
! 157: /* Send ARP reply */
! 158: arp_reply(d, ah);
! 159: }
! 160: return -1;
! 161: }
! 162:
! 163: if (etype != ETHERTYPE_IP) {
! 164: #ifdef NET_DEBUG
! 165: if (debug)
! 166: printf("readudp: not IP. ether_type=%x\n", etype);
! 167: #endif
! 168: return -1;
! 169: }
! 170:
! 171: /* Check ip header */
! 172: if (ip->ip_v != IPVERSION ||
! 173: ip->ip_p != IPPROTO_UDP) { /* half char */
! 174: #ifdef NET_DEBUG
! 175: if (debug)
! 176: printf("readudp: IP version or not UDP. ip_v=%d ip_p=%d\n", ip->ip_v, ip->ip_p);
! 177: #endif
! 178: return -1;
! 179: }
! 180:
! 181: hlen = ip->ip_hl << 2;
! 182: if (hlen < sizeof(*ip) ||
! 183: in_cksum(ip, hlen) != 0) {
! 184: #ifdef NET_DEBUG
! 185: if (debug)
! 186: printf("readudp: short hdr or bad cksum.\n");
! 187: #endif
! 188: return -1;
! 189: }
! 190: NTOHS(ip->ip_len);
! 191: if (n < ip->ip_len) {
! 192: #ifdef NET_DEBUG
! 193: if (debug)
! 194: printf("readudp: bad length %d < %d.\n", n, ip->ip_len);
! 195: #endif
! 196: return -1;
! 197: }
! 198: if (d->myip.s_addr && ip->ip_dst.s_addr != d->myip.s_addr) {
! 199: #ifdef NET_DEBUG
! 200: if (debug) {
! 201: printf("readudp: bad saddr %s != ", inet_ntoa(d->myip));
! 202: printf("%s\n", inet_ntoa(ip->ip_dst));
! 203: }
! 204: #endif
! 205: return -1;
! 206: }
! 207:
! 208: /* If there were ip options, make them go away */
! 209: if (hlen != sizeof(*ip)) {
! 210: bcopy(((u_char *)ip) + hlen, uh, len - hlen);
! 211: ip->ip_len = sizeof(*ip);
! 212: n -= hlen - sizeof(*ip);
! 213: }
! 214: if (uh->uh_dport != d->myport) {
! 215: #ifdef NET_DEBUG
! 216: if (debug)
! 217: printf("readudp: bad dport %d != %d\n",
! 218: d->myport, ntohs(uh->uh_dport));
! 219: #endif
! 220: return -1;
! 221: }
! 222:
! 223: if (uh->uh_sum) {
! 224: n = ntohs(uh->uh_ulen) + sizeof(*ip);
! 225: if (n > RECV_SIZE - ETHER_SIZE) {
! 226: printf("readudp: huge packet, udp len %ld\n", (long)n);
! 227: return -1;
! 228: }
! 229:
! 230: /* Check checksum (must save and restore ip header) */
! 231: tip = *ip;
! 232: ui = (struct udpiphdr *)ip;
! 233: bzero(ui->ui_x1, sizeof(ui->ui_x1));
! 234: ui->ui_len = uh->uh_ulen;
! 235: if (in_cksum(ui, n) != 0) {
! 236: #ifdef NET_DEBUG
! 237: if (debug)
! 238: printf("readudp: bad cksum\n");
! 239: #endif
! 240: *ip = tip;
! 241: return -1;
! 242: }
! 243: *ip = tip;
! 244: }
! 245: NTOHS(uh->uh_dport);
! 246: NTOHS(uh->uh_sport);
! 247: NTOHS(uh->uh_ulen);
! 248: if (uh->uh_ulen < sizeof(*uh)) {
! 249: #ifdef NET_DEBUG
! 250: if (debug)
! 251: printf("readudp: bad udp len %d < %d\n",
! 252: uh->uh_ulen, sizeof(*uh));
! 253: #endif
! 254: return -1;
! 255: }
! 256:
! 257: n -= sizeof(*ip) + sizeof(*uh);
! 258: return (n);
! 259: }
! 260:
! 261: /*
! 262: * Send a packet and wait for a reply, with exponential backoff.
! 263: *
! 264: * The send routine must return the actual number of bytes written.
! 265: *
! 266: * The receive routine can indicate success by returning the number of
! 267: * bytes read; it can return 0 to indicate EOF; it can return -1 with a
! 268: * non-zero errno to indicate failure; finally, it can return -1 with a
! 269: * zero errno to indicate it isn't done yet.
! 270: */
! 271: ssize_t
! 272: sendrecv(struct iodesc *d, ssize_t (*sproc)(struct iodesc *, void *, size_t),
! 273: void *sbuf, size_t ssize,
! 274: ssize_t (*rproc)(struct iodesc *, void *, size_t, time_t),
! 275: void *rbuf, size_t rsize)
! 276: {
! 277: ssize_t cc;
! 278: time_t t, tmo, tlast;
! 279: long tleft;
! 280:
! 281: #ifdef NET_DEBUG
! 282: if (debug)
! 283: printf("sendrecv: called\n");
! 284: #endif
! 285:
! 286: tmo = MINTMO;
! 287: tlast = tleft = 0;
! 288: t = getsecs();
! 289: for (;;) {
! 290: if (tleft <= 0) {
! 291: if (tmo >= MAXTMO) {
! 292: errno = ETIMEDOUT;
! 293: return -1;
! 294: }
! 295: cc = (*sproc)(d, sbuf, ssize);
! 296: if (cc < 0 || (size_t)cc < ssize)
! 297: panic("sendrecv: short write! (%d < %d)",
! 298: cc, ssize);
! 299:
! 300: tleft = tmo;
! 301: tmo <<= 1;
! 302: if (tmo > MAXTMO)
! 303: tmo = MAXTMO;
! 304: tlast = t;
! 305: }
! 306:
! 307: /* Try to get a packet and process it. */
! 308: cc = (*rproc)(d, rbuf, rsize, tleft);
! 309: /* Return on data, EOF or real error. */
! 310: if (cc != -1 || errno != 0)
! 311: return (cc);
! 312:
! 313: /* Timed out or didn't get the packet we're waiting for */
! 314: t = getsecs();
! 315: tleft -= t - tlast;
! 316: tlast = t;
! 317: }
! 318: }
! 319:
! 320: /*
! 321: * Like inet_addr() in the C library, but we only accept base-10.
! 322: * Return values are in network order.
! 323: */
! 324: n_long
! 325: inet_addr(char *cp)
! 326: {
! 327: u_long val;
! 328: int n;
! 329: char c;
! 330: u_int parts[4];
! 331: u_int *pp = parts;
! 332:
! 333: for (;;) {
! 334: /*
! 335: * Collect number up to ``.''.
! 336: * Values are specified as for C:
! 337: * 0x=hex, 0=octal, other=decimal.
! 338: */
! 339: val = 0;
! 340: while ((c = *cp) != '\0') {
! 341: if (c >= '0' && c <= '9') {
! 342: val = (val * 10) + (c - '0');
! 343: cp++;
! 344: continue;
! 345: }
! 346: break;
! 347: }
! 348: if (*cp == '.') {
! 349: /*
! 350: * Internet format:
! 351: * a.b.c.d
! 352: * a.b.c (with c treated as 16-bits)
! 353: * a.b (with b treated as 24 bits)
! 354: */
! 355: if (pp >= parts + 3 || val > 0xff)
! 356: goto bad;
! 357: *pp++ = val, cp++;
! 358: } else
! 359: break;
! 360: }
! 361: /*
! 362: * Check for trailing characters.
! 363: */
! 364: if (*cp != '\0')
! 365: goto bad;
! 366:
! 367: /*
! 368: * Concoct the address according to
! 369: * the number of parts specified.
! 370: */
! 371: n = pp - parts + 1;
! 372: switch (n) {
! 373:
! 374: case 1: /* a -- 32 bits */
! 375: break;
! 376:
! 377: case 2: /* a.b -- 8.24 bits */
! 378: if (val > 0xffffff)
! 379: goto bad;
! 380: val |= parts[0] << 24;
! 381: break;
! 382:
! 383: case 3: /* a.b.c -- 8.8.16 bits */
! 384: if (val > 0xffff)
! 385: goto bad;
! 386: val |= (parts[0] << 24) | (parts[1] << 16);
! 387: break;
! 388:
! 389: case 4: /* a.b.c.d -- 8.8.8.8 bits */
! 390: if (val > 0xff)
! 391: goto bad;
! 392: val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
! 393: break;
! 394: }
! 395:
! 396: return (htonl(val));
! 397: bad:
! 398: return (htonl(INADDR_NONE));
! 399: }
! 400:
! 401: char *
! 402: inet_ntoa(struct in_addr ia)
! 403: {
! 404: return (intoa(ia.s_addr));
! 405: }
! 406:
! 407: /* Similar to inet_ntoa() */
! 408: char *
! 409: intoa(n_long addr)
! 410: {
! 411: char *cp;
! 412: u_int byte;
! 413: int n;
! 414: static char buf[sizeof(".255.255.255.255")];
! 415:
! 416: NTOHL(addr);
! 417: cp = &buf[sizeof buf];
! 418: *--cp = '\0';
! 419:
! 420: n = 4;
! 421: do {
! 422: byte = addr & 0xff;
! 423: *--cp = byte % 10 + '0';
! 424: byte /= 10;
! 425: if (byte > 0) {
! 426: *--cp = byte % 10 + '0';
! 427: byte /= 10;
! 428: if (byte > 0)
! 429: *--cp = byte + '0';
! 430: }
! 431: *--cp = '.';
! 432: addr >>= 8;
! 433: } while (--n > 0);
! 434:
! 435: return (cp+1);
! 436: }
! 437:
! 438: static char *
! 439: number(char *s, int *n)
! 440: {
! 441: for (*n = 0; isdigit(*s); s++)
! 442: *n = (*n * 10) + *s - '0';
! 443: return s;
! 444: }
! 445:
! 446: n_long
! 447: ip_convertaddr(char *p)
! 448: {
! 449: #define IP_ANYADDR 0
! 450: n_long addr = 0, n;
! 451:
! 452: if (p == (char *)0 || *p == '\0')
! 453: return IP_ANYADDR;
! 454: p = number(p, &n);
! 455: addr |= (n << 24) & 0xff000000;
! 456: if (*p == '\0' || *p++ != '.')
! 457: return IP_ANYADDR;
! 458: p = number(p, &n);
! 459: addr |= (n << 16) & 0xff0000;
! 460: if (*p == '\0' || *p++ != '.')
! 461: return IP_ANYADDR;
! 462: p = number(p, &n);
! 463: addr |= (n << 8) & 0xff00;
! 464: if (*p == '\0' || *p++ != '.')
! 465: return IP_ANYADDR;
! 466: p = number(p, &n);
! 467: addr |= n & 0xff;
! 468: if (*p != '\0')
! 469: return IP_ANYADDR;
! 470:
! 471: return htonl(addr);
! 472: }
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