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 __FBSDID("$FreeBSD$");
  40
  41 #include <sys/param.h>
  42 #include <sys/socket.h>
  43
  44 #include <string.h>
  45
  46 #include <net/if.h>
  47 #include <netinet/in.h>
  48 #include <netinet/if_ether.h>
  49 #include <netinet/in_systm.h>
  50
  51 #include <netinet/in_pcb.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 /*
  61  * Send a packet and wait for a reply, with exponential backoff.
  62  *
  63  * The send routine must return the actual number of bytes written,
  64  * or -1 on error.
  65  *
  66  * The receive routine can indicate success by returning the number of
  67  * bytes read; it can return 0 to indicate EOF; it can return -1 with a
  68  * non-zero errno to indicate failure; finally, it can return -1 with a
  69  * zero errno to indicate it isn't done yet.
  70  */
  71 ssize_t
  72 sendrecv(struct iodesc *d,
  73         ssize_t (*sproc)(struct iodesc *, void *, size_t),
  74         void *sbuf, size_t ssize,
  75         ssize_t (*rproc)(struct iodesc *, void *, size_t, time_t),
  76         void *rbuf, size_t rsize)
  77 {
  78         ssize_t cc;
  79         time_t t, tmo, tlast;
  80         long tleft;
  81
  82 #ifdef NET_DEBUG
  83         if (debug)
  84                 printf("sendrecv: called\n");
  85 #endif
  86
  87         tmo = MINTMO;
  88         tlast = 0;
  89         tleft = 0;
  90         t = getsecs();
  91         for (;;) {
  92                 if (tleft <= 0) {
  93                         if (tmo >= MAXTMO) {
  94                                 errno = ETIMEDOUT;
  95                                 return -1;
  96                         }
  97                         cc = (*sproc)(d, sbuf, ssize);
  98                         if (cc != -1 && cc < ssize)
  99                                 panic("sendrecv: short write! (%zd < %zd)",
 100                                     cc, ssize);
 101
 102                         tleft = tmo;
 103                         tmo += MINTMO;
 104                         if (tmo > MAXTMO)
 105                                 tmo = MAXTMO;
 106
 107                         if (cc == -1) {
 108                                 /* Error on transmit; wait before retrying */
 109                                 while ((getsecs() - t) < tmo)
 110                                         ;
 111                                 tleft = 0;
 112                                 continue;
 113                         }
 114
 115                         tlast = t;
 116                 }
 117
 118                 /* Try to get a packet and process it. */
 119                 cc = (*rproc)(d, rbuf, rsize, tleft);
 120                 /* Return on data, EOF or real error. */
 121                 if (cc != -1 || errno != 0)
 122                         return (cc);
 123
 124                 /* Timed out or didn't get the packet we're waiting for */
 125                 t = getsecs();
 126                 tleft -= t - tlast;
 127                 tlast = t;
 128         }
 129 }
 130
 131 /*
 132  * Like inet_addr() in the C library, but we only accept base-10.
 133  * Return values are in network order.
 134  */
 135 n_long
 136 inet_addr(char *cp)
 137 {
 138         u_long val;
 139         int n;
 140         char c;
 141         u_int parts[4];
 142         u_int *pp = parts;
 143
 144         for (;;) {
 145                 /*
 146                  * Collect number up to ``.''.
 147                  * Values are specified as for C:
 148                  * 0x=hex, 0=octal, other=decimal.
 149                  */
 150                 val = 0;
 151                 while ((c = *cp) != '\0') {
 152                         if (c >= '0' && c <= '9') {
 153                                 val = (val * 10) + (c - '0');
 154                                 cp++;
 155                                 continue;
 156                         }
 157                         break;
 158                 }
 159                 if (*cp == '.') {
 160                         /*
 161                          * Internet format:
 162                          *      a.b.c.d
 163                          *      a.b.c   (with c treated as 16-bits)
 164                          *      a.b     (with b treated as 24 bits)
 165                          */
 166                         if (pp >= parts + 3 || val > 0xff)
 167                                 goto bad;
 168                         *pp++ = val, cp++;
 169                 } else
 170                         break;
 171         }
 172         /*
 173          * Check for trailing characters.
 174          */
 175         if (*cp != '\0')
 176                 goto bad;
 177
 178         /*
 179          * Concoct the address according to
 180          * the number of parts specified.
 181          */
 182         n = pp - parts + 1;
 183         switch (n) {
 184
 185         case 1:                         /* a -- 32 bits */
 186                 break;
 187
 188         case 2:                         /* a.b -- 8.24 bits */
 189                 if (val > 0xffffff)
 190                         goto bad;
 191                 val |= parts[0] << 24;
 192                 break;
 193
 194         case 3:                         /* a.b.c -- 8.8.16 bits */
 195                 if (val > 0xffff)
 196                         goto bad;
 197                 val |= (parts[0] << 24) | (parts[1] << 16);
 198                 break;
 199
 200         case 4:                         /* a.b.c.d -- 8.8.8.8 bits */
 201                 if (val > 0xff)
 202                         goto bad;
 203                 val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
 204                 break;
 205         }
 206
 207         return (htonl(val));
 208  bad:
 209         return (htonl(INADDR_NONE));
 210 }
 211
 212 char *
 213 inet_ntoa(struct in_addr ia)
 214 {
 215         return (intoa(ia.s_addr));
 216 }
 217
 218 /* Similar to inet_ntoa() */
 219 char *
 220 intoa(n_long addr)
 221 {
 222         char *cp;
 223         u_int byte;
 224         int n;
 225         static char buf[17];    /* strlen(".255.255.255.255") + 1 */
 226
 227         addr = ntohl(addr);
 228         cp = &buf[sizeof buf];
 229         *--cp = '\0';
 230
 231         n = 4;
 232         do {
 233                 byte = addr & 0xff;
 234                 *--cp = byte % 10 + '0';
 235                 byte /= 10;
 236                 if (byte > 0) {
 237                         *--cp = byte % 10 + '0';
 238                         byte /= 10;
 239                         if (byte > 0)
 240                                 *--cp = byte + '0';
 241                 }
 242                 *--cp = '.';
 243                 addr >>= 8;
 244         } while (--n > 0);
 245
 246         return (cp+1);
 247 }
 248
 249 static char *
 250 number(char *s, int *n)
 251 {
 252         for (*n = 0; isdigit(*s); s++)
 253                 *n = (*n * 10) + *s - '0';
 254         return s;
 255 }
 256
 257 n_long
 258 ip_convertaddr(char *p)
 259 {
 260 #define IP_ANYADDR      0
 261         n_long addr = 0, n;
 262
 263         if (p == NULL || *p == '\0')
 264                 return IP_ANYADDR;
 265         p = number(p, &n);
 266         addr |= (n << 24) & 0xff000000;
 267         if (*p == '\0' || *p++ != '.')
 268                 return IP_ANYADDR;
 269         p = number(p, &n);
 270         addr |= (n << 16) & 0xff0000;
 271         if (*p == '\0' || *p++ != '.')
 272                 return IP_ANYADDR;
 273         p = number(p, &n);
 274         addr |= (n << 8) & 0xff00;
 275         if (*p == '\0' || *p++ != '.')
 276                 return IP_ANYADDR;
 277         p = number(p, &n);
 278         addr |= n & 0xff;
 279         if (*p != '\0')
 280                 return IP_ANYADDR;
 281
 282         return htonl(addr);
 283 }