usr/src/boot/lib/libstand/net.c

   1 /*      $NetBSD: net.c,v 1.20 1997/12/26 22:41:30 scottr Exp $  */
   2
   3 /*
   4  * Copyright (c) 1992 Regents of the University of California.
   5  * All rights reserved.
   6  *
   7  * This software was developed by the Computer Systems Engineering group
   8  * at Lawrence Berkeley Laboratory under DARPA contract BG 91-66 and
   9  * contributed to Berkeley.
  10  *
  11  * Redistribution and use in source and binary forms, with or without
  12  * modification, are permitted provided that the following conditions
  13  * are met:
  14  * 1. Redistributions of source code must retain the above copyright
  15  *    notice, this list of conditions and the following disclaimer.
  16  * 2. Redistributions in binary form must reproduce the above copyright
  17  *    notice, this list of conditions and the following disclaimer in the
  18  *    documentation and/or other materials provided with the distribution.
  19  * 4. Neither the name of the University nor the names of its contributors
  20  *    may be used to endorse or promote products derived from this software
  21  *    without specific prior written permission.
  22  *
  23  * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
  24  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  25  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  26  * ARE DISCLAIMED.  IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
  27  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  28  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  29  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  30  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  31  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  32  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  33  * SUCH DAMAGE.
  34  *
  35  * @(#) Header: net.c,v 1.9 93/08/06 19:32:15 leres Exp  (LBL)
  36  */
  37
  38 #include <sys/cdefs.h>
  39
  40 #include <sys/param.h>
  41 #include <sys/socket.h>
  42
  43 #include <string.h>
  44
  45 #include <net/if.h>
  46 #include <netinet/in.h>
  47 #include <netinet/if_ether.h>
  48 #include <netinet/in_systm.h>
  49
  50 #include <netinet/in_pcb.h>
  51 #include <netinet/ip.h>
  52 #include <netinet/ip_var.h>
  53 #include <netinet/udp.h>
  54 #include <netinet/udp_var.h>
  55
  56 #include "stand.h"
  57 #include "net.h"
  58
  59 /*
  60  * Maximum wait time for sending and receiving before we give up and timeout.
  61  * If set to 0, operations will eventually timeout completely, but send/recv
  62  * timeouts must progress exponentially from MINTMO to MAXTMO before final
  63  * timeout is hit.
  64  */
  65 #ifndef MAXWAIT
  66 #define MAXWAIT 0       /* seconds */
  67 #endif
  68
  69 #if MAXWAIT < 0
  70 #error MAXWAIT must not be a negative number
  71 #endif
  72
  73 /*
  74  * Send a packet and wait for a reply, with exponential backoff.
  75  *
  76  * The send routine must return the actual number of bytes written,
  77  * or -1 on error.
  78  *
  79  * The receive routine can indicate success by returning the number of
  80  * bytes read; it can return 0 to indicate EOF; it can return -1 with a
  81  * non-zero errno to indicate failure; finally, it can return -1 with a
  82  * zero errno to indicate it isn't done yet.
  83  */
  84 ssize_t
  85 sendrecv(struct iodesc *d,
  86     ssize_t (*sproc)(struct iodesc *, void *, size_t),
  87     void *sbuf, size_t ssize,
  88     ssize_t (*rproc)(struct iodesc *, void **, void**, time_t, void *),
  89     void **pkt, void **payload, void *recv_extra)
  90 {
  91         ssize_t cc;
  92         time_t t, tmo, tlast;
  93         time_t tref;
  94         long tleft;
  95
  96 #ifdef NET_DEBUG
  97         if (debug)
  98                 printf("sendrecv: called\n");
  99 #endif
 100
 101         tmo = MINTMO;
 102         tlast = 0;
 103         tleft = 0;
 104         tref = getsecs();
 105         t = getsecs();
 106         for (;;) {
 107                 if (MAXWAIT > 0 && (getsecs() - tref) >= MAXWAIT) {
 108                         errno = ETIMEDOUT;
 109                         return (-1);
 110                 }
 111                 if (tleft <= 0) {
 112                         if (tmo >= MAXTMO) {
 113                                 errno = ETIMEDOUT;
 114                                 return (-1);
 115                         }
 116                         cc = (*sproc)(d, sbuf, ssize);
 117                         if (cc != -1 && cc < ssize)
 118                                 panic("sendrecv: short write! (%zd < %zd)",
 119                                     cc, ssize);
 120
 121                         tleft = tmo;
 122                         tmo += MINTMO;
 123                         if (tmo > MAXTMO)
 124                                 tmo = MAXTMO;
 125
 126                         if (cc == -1) {
 127                                 /* Error on transmit; wait before retrying */
 128                                 while ((getsecs() - t) < tmo)
 129                                         ;
 130                                 tleft = 0;
 131                                 continue;
 132                         }
 133
 134                         tlast = t;
 135                 }
 136
 137                 /* Try to get a packet and process it. */
 138                 cc = (*rproc)(d, pkt, payload, tleft, recv_extra);
 139                 /* Return on data, EOF or real error. */
 140                 if (cc != -1 || (errno != 0 && errno != ETIMEDOUT))
 141                         return (cc);
 142
 143                 /* Timed out or didn't get the packet we're waiting for */
 144                 t = getsecs();
 145                 tleft -= t - tlast;
 146                 tlast = t;
 147         }
 148 }
 149
 150 /*
 151  * Like inet_addr() in the C library, but we only accept base-10.
 152  * Return values are in network order.
 153  */
 154 n_long
 155 inet_addr(char *cp)
 156 {
 157         unsigned long val;
 158         int n;
 159         char c;
 160         unsigned int parts[4];
 161         unsigned int *pp = parts;
 162
 163         for (;;) {
 164                 /*
 165                  * Collect number up to ``.''.
 166                  * Values are specified as for C:
 167                  * 0x=hex, 0=octal, other=decimal.
 168                  */
 169                 val = 0;
 170                 while ((c = *cp) != '\0') {
 171                         if (c >= '0' && c <= '9') {
 172                                 val = (val * 10) + (c - '0');
 173                                 cp++;
 174                                 continue;
 175                         }
 176                         break;
 177                 }
 178                 if (*cp == '.') {
 179                         /*
 180                          * Internet format:
 181                          *      a.b.c.d
 182                          *      a.b.c   (with c treated as 16-bits)
 183                          *      a.b     (with b treated as 24 bits)
 184                          */
 185                         if (pp >= parts + 3 || val > 0xff)
 186                                 goto bad;
 187                         *pp++ = val, cp++;
 188                 } else
 189                         break;
 190         }
 191         /*
 192          * Check for trailing characters.
 193          */
 194         if (*cp != '\0')
 195                 goto bad;
 196
 197         /*
 198          * Concoct the address according to
 199          * the number of parts specified.
 200          */
 201         n = pp - parts + 1;
 202         switch (n) {
 203
 204         case 1:                         /* a -- 32 bits */
 205                 break;
 206
 207         case 2:                         /* a.b -- 8.24 bits */
 208                 if (val > 0xffffff)
 209                         goto bad;
 210                 val |= parts[0] << 24;
 211                 break;
 212
 213         case 3:                         /* a.b.c -- 8.8.16 bits */
 214                 if (val > 0xffff)
 215                         goto bad;
 216                 val |= (parts[0] << 24) | (parts[1] << 16);
 217                 break;
 218
 219         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 220                 if (val > 0xff)
 221                         goto bad;
 222                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 223                 break;
 224         }
 225
 226         return (htonl(val));
 227 bad:
 228         return (htonl(INADDR_NONE));
 229 }
 230
 231 char *
 232 inet_ntoa(struct in_addr ia)
 233 {
 234         return (intoa(ia.s_addr));
 235 }
 236
 237 /* Similar to inet_ntoa() */
 238 char *
 239 intoa(n_long addr)
 240 {
 241         char *cp;
 242         unsigned int byte;
 243         int n;
 244         static char buf[17];    /* strlen(".255.255.255.255") + 1 */
 245
 246         addr = ntohl(addr);
 247         cp = &buf[sizeof (buf)];
 248         *--cp = '\0';
 249
 250         n = 4;
 251         do {
 252                 byte = addr & 0xff;
 253                 *--cp = byte % 10 + '0';
 254                 byte /= 10;
 255                 if (byte > 0) {
 256                         *--cp = byte % 10 + '0';
 257                         byte /= 10;
 258                         if (byte > 0)
 259                                 *--cp = byte + '0';
 260                 }
 261                 *--cp = '.';
 262                 addr >>= 8;
 263         } while (--n > 0);
 264
 265         return (cp+1);
 266 }
 267
 268 static char *
 269 number(char *s, uint32_t *n)
 270 {
 271         for (*n = 0; isdigit(*s); s++)
 272                 *n = (*n * 10) + *s - '0';
 273         return (s);
 274 }
 275
 276 n_long
 277 ip_convertaddr(char *p)
 278 {
 279 #define IP_ANYADDR      0
 280         uint32_t addr = 0, n;
 281
 282         if (p == NULL || *p == '\0')
 283                 return (IP_ANYADDR);
 284         p = number(p, &n);
 285         addr |= (n << 24) & 0xff000000;
 286         if (*p == '\0' || *p++ != '.')
 287                 return (IP_ANYADDR);
 288         p = number(p, &n);
 289         addr |= (n << 16) & 0xff0000;
 290         if (*p == '\0' || *p++ != '.')
 291                 return (IP_ANYADDR);
 292         p = number(p, &n);
 293         addr |= (n << 8) & 0xff00;
 294         if (*p == '\0' || *p++ != '.')
 295                 return (IP_ANYADDR);
 296         p = number(p, &n);
 297         addr |= n & 0xff;
 298         if (*p != '\0')
 299                 return (IP_ANYADDR);
 300
 301         return (htonl(addr));
 302 }