usr.sbin/ppp/udp.c

   1 /*-
   2  * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *    notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *    notice, this list of conditions and the following disclaimer in the
  12  *    documentation and/or other materials provided with the distribution.
  13  *
  14  * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
  15  * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
  16  * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  17  * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
  18  * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  19  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
  20  * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
  21  * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
  22  * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
  23  * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
  24  * SUCH DAMAGE.
  25  *
  26  * $FreeBSD: src/usr.sbin/ppp/udp.c,v 1.10.2.4 2002/09/01 02:12:32 brian Exp $
  27  * $DragonFly: src/usr.sbin/ppp/udp.c,v 1.2 2003/06/17 04:30:01 dillon Exp $
  28  */
  29
  30 #include <sys/types.h>
  31 #include <sys/socket.h>
  32 #include <netinet/in.h>
  33 #include <arpa/inet.h>
  34 #include <netdb.h>
  35
  36 #include <errno.h>
  37 #include <stdio.h>
  38 #include <stdlib.h>
  39 #include <string.h>
  40 #include <sysexits.h>
  41 #include <sys/stat.h>
  42 #include <sys/uio.h>
  43 #include <termios.h>
  44 #include <unistd.h>
  45
  46 #include "layer.h"
  47 #include "defs.h"
  48 #include "mbuf.h"
  49 #include "log.h"
  50 #include "timer.h"
  51 #include "lqr.h"
  52 #include "hdlc.h"
  53 #include "throughput.h"
  54 #include "fsm.h"
  55 #include "lcp.h"
  56 #include "ccp.h"
  57 #include "link.h"
  58 #include "async.h"
  59 #include "descriptor.h"
  60 #include "physical.h"
  61 #include "main.h"
  62 #include "udp.h"
  63
  64
  65 #define UDP_CONNECTED           1
  66 #define UDP_UNCONNECTED         2
  67 #define UDP_MAYBEUNCONNECTED    3
  68
  69 struct udpdevice {
  70   struct device dev;            /* What struct physical knows about */
  71   struct sockaddr_in sock;      /* peer address */
  72   unsigned connected : 2;       /* Have we connect()d ? */
  73 };
  74
  75 #define device2udp(d) ((d)->type == UDP_DEVICE ? (struct udpdevice *)d : NULL)
  76
  77 int
  78 udp_DeviceSize(void)
  79 {
  80   return sizeof(struct udpdevice);
  81 }
  82
  83 static ssize_t
  84 udp_Sendto(struct physical *p, const void *v, size_t n)
  85 {
  86   struct udpdevice *dev = device2udp(p->handler);
  87   int ret;
  88
  89   switch (dev->connected) {
  90     case UDP_CONNECTED:
  91       ret = write(p->fd, v, n);
  92       break;
  93
  94     case UDP_UNCONNECTED:
  95     default:
  96       ret = sendto(p->fd, v, n, 0, (struct sockaddr *)&dev->sock,
  97                    sizeof dev->sock);
  98       break;
  99   }
 100   if (dev->connected == UDP_MAYBEUNCONNECTED) {
 101     if (ret == -1 && errno == EISCONN) {
 102       dev->connected = UDP_CONNECTED;
 103       ret = write(p->fd, v, n);
 104     } else
 105       dev->connected = UDP_UNCONNECTED;
 106   }
 107
 108   return ret;
 109 }
 110
 111 static ssize_t
 112 udp_Recvfrom(struct physical *p, void *v, size_t n)
 113 {
 114   struct udpdevice *dev = device2udp(p->handler);
 115   int sz, ret;
 116
 117   if (dev->connected == UDP_CONNECTED)
 118     return read(p->fd, v, n);
 119
 120   sz = sizeof dev->sock;
 121   ret = recvfrom(p->fd, v, n, 0, (struct sockaddr *)&dev->sock, &sz);
 122
 123   if (*p->name.full == '\0') {
 124     snprintf(p->name.full, sizeof p->name.full, "%s:%d/udp",
 125              inet_ntoa(dev->sock.sin_addr), ntohs(dev->sock.sin_port));
 126     p->name.base = p->name.full;
 127   }
 128
 129   return ret;
 130 }
 131
 132 static void
 133 udp_Free(struct physical *p)
 134 {
 135   struct udpdevice *dev = device2udp(p->handler);
 136
 137   free(dev);
 138 }
 139
 140 static void
 141 udp_device2iov(struct device *d, struct iovec *iov, int *niov,
 142                int maxiov, int *auxfd, int *nauxfd)
 143 {
 144   int sz = physical_MaxDeviceSize();
 145
 146   iov[*niov].iov_base = realloc(d, sz);
 147   if (iov[*niov].iov_base == NULL) {
 148     log_Printf(LogALERT, "Failed to allocate memory: %d\n", sz);
 149     AbortProgram(EX_OSERR);
 150   }
 151   iov[*niov].iov_len = sz;
 152   (*niov)++;
 153 }
 154
 155 static const struct device baseudpdevice = {
 156   UDP_DEVICE,
 157   "udp",
 158   0,
 159   { CD_NOTREQUIRED, 0 },
 160   NULL,
 161   NULL,
 162   NULL,
 163   NULL,
 164   NULL,
 165   NULL,
 166   NULL,
 167   udp_Free,
 168   udp_Recvfrom,
 169   udp_Sendto,
 170   udp_device2iov,
 171   NULL,
 172   NULL,
 173   NULL
 174 };
 175
 176 struct device *
 177 udp_iov2device(int type, struct physical *p, struct iovec *iov, int *niov,
 178                int maxiov, int *auxfd, int *nauxfd)
 179 {
 180   if (type == UDP_DEVICE) {
 181     struct udpdevice *dev = (struct udpdevice *)iov[(*niov)++].iov_base;
 182
 183     dev = realloc(dev, sizeof *dev);    /* Reduce to the correct size */
 184     if (dev == NULL) {
 185       log_Printf(LogALERT, "Failed to allocate memory: %d\n",
 186                  (int)(sizeof *dev));
 187       AbortProgram(EX_OSERR);
 188     }
 189
 190     /* Refresh function pointers etc */
 191     memcpy(&dev->dev, &baseudpdevice, sizeof dev->dev);
 192
 193     physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNC);
 194     return &dev->dev;
 195   }
 196
 197   return NULL;
 198 }
 199
 200 static struct udpdevice *
 201 udp_CreateDevice(struct physical *p, char *host, char *port)
 202 {
 203   struct udpdevice *dev;
 204   struct servent *sp;
 205
 206   if ((dev = malloc(sizeof *dev)) == NULL) {
 207     log_Printf(LogWARN, "%s: Cannot allocate a udp device: %s\n",
 208                p->link.name, strerror(errno));
 209     return NULL;
 210   }
 211
 212   dev->sock.sin_family = AF_INET;
 213   dev->sock.sin_addr = GetIpAddr(host);
 214   if (dev->sock.sin_addr.s_addr == INADDR_NONE) {
 215     log_Printf(LogWARN, "%s: %s: unknown host\n", p->link.name, host);
 216     free(dev);
 217     return NULL;
 218   }
 219   dev->sock.sin_port = htons(atoi(port));
 220   if (dev->sock.sin_port == 0) {
 221     sp = getservbyname(port, "udp");
 222     if (sp)
 223       dev->sock.sin_port = sp->s_port;
 224     else {
 225       log_Printf(LogWARN, "%s: %s: unknown service\n", p->link.name, port);
 226       free(dev);
 227       return NULL;
 228     }
 229   }
 230
 231   log_Printf(LogPHASE, "%s: Connecting to %s:%s/udp\n", p->link.name,
 232              host, port);
 233
 234   p->fd = socket(PF_INET, SOCK_DGRAM, 0);
 235   if (p->fd >= 0) {
 236     log_Printf(LogDEBUG, "%s: Opened udp socket %s\n", p->link.name,
 237                p->name.full);
 238     if (connect(p->fd, (struct sockaddr *)&dev->sock, sizeof dev->sock) == 0) {
 239       dev->connected = UDP_CONNECTED;
 240       return dev;
 241     } else
 242       log_Printf(LogWARN, "%s: connect: %s\n", p->name.full, strerror(errno));
 243   } else
 244     log_Printf(LogWARN, "%s: socket: %s\n", p->name.full, strerror(errno));
 245
 246   close(p->fd);
 247   p->fd = -1;
 248   free(dev);
 249
 250   return NULL;
 251 }
 252
 253 struct device *
 254 udp_Create(struct physical *p)
 255 {
 256   char *cp, *host, *port, *svc;
 257   struct udpdevice *dev;
 258
 259   dev = NULL;
 260   if (p->fd < 0) {
 261     if ((cp = strchr(p->name.full, ':')) != NULL && !strchr(cp + 1, ':')) {
 262       *cp = '\0';
 263       host = p->name.full;
 264       port = cp + 1;
 265       svc = strchr(port, '/');
 266       if (svc && strcasecmp(svc, "/udp")) {
 267         *cp = ':';
 268         return NULL;
 269       }
 270       if (svc) {
 271         p->fd--;     /* We own the device but maybe can't use it - change fd */
 272         *svc = '\0';
 273       }
 274
 275       if (*host && *port)
 276         dev = udp_CreateDevice(p, host, port);
 277
 278       *cp = ':';
 279       if (svc)
 280         *svc = '/';
 281     }
 282   } else {
 283     /* See if we're a connected udp socket */
 284     struct stat st;
 285
 286     if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
 287       int type, sz;
 288
 289       sz = sizeof type;
 290       if (getsockopt(p->fd, SOL_SOCKET, SO_TYPE, &type, &sz) == -1) {
 291         log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
 292         close(p->fd);
 293         p->fd = -1;
 294         return NULL;
 295       }
 296
 297       if (sz == sizeof type && type == SOCK_DGRAM) {
 298         struct sockaddr_in sock;
 299         struct sockaddr *sockp = (struct sockaddr *)&sock;
 300
 301         if ((dev = malloc(sizeof *dev)) == NULL) {
 302           log_Printf(LogWARN, "%s: Cannot allocate a udp device: %s\n",
 303                      p->link.name, strerror(errno));
 304           return NULL;
 305         }
 306
 307         if (getpeername(p->fd, sockp, &sz) == 0) {
 308           log_Printf(LogPHASE, "%s: Link is a connected udp socket\n",
 309                      p->link.name);
 310           dev->connected = UDP_CONNECTED;
 311         } else {
 312           log_Printf(LogPHASE, "%s: Link is a disconnected udp socket\n",
 313                      p->link.name);
 314
 315           dev->connected = UDP_MAYBEUNCONNECTED;
 316
 317           if (p->link.lcp.cfg.openmode != OPEN_PASSIVE) {
 318             log_Printf(LogPHASE, "%s:   Changing openmode to PASSIVE\n",
 319                        p->link.name);
 320             p->link.lcp.cfg.openmode = OPEN_PASSIVE;
 321           }
 322         }
 323       }
 324     }
 325   }
 326
 327   if (dev) {
 328     memcpy(&dev->dev, &baseudpdevice, sizeof dev->dev);
 329     physical_SetupStack(p, dev->dev.name, PHYSICAL_FORCE_SYNC);
 330     if (p->cfg.cd.necessity != CD_DEFAULT)
 331       log_Printf(LogWARN, "Carrier settings ignored\n");
 332     return &dev->dev;
 333   }
 334
 335   return NULL;
 336 }