1/*-
2 * SPDX-License-Identifier: BSD-2-Clause
3 *
4 * Copyright (c) 1999 Brian Somers <brian@Awfulhak.org>
5 * All rights reserved.
6 *
7 * Redistribution and use in source and binary forms, with or without
8 * modification, are permitted provided that the following conditions
9 * are met:
10 * 1. Redistributions of source code must retain the above copyright
11 *    notice, this list of conditions and the following disclaimer.
12 * 2. Redistributions in binary form must reproduce the above copyright
13 *    notice, this list of conditions and the following disclaimer in the
14 *    documentation and/or other materials provided with the distribution.
15 *
16 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
17 * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
18 * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
19 * ARE DISCLAIMED.  IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
20 * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
21 * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
22 * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
23 * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
24 * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
25 * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
26 * SUCH DAMAGE.
27 */
28
29#include <sys/types.h>
30#include <sys/socket.h>
31#include <netinet/in.h>
32#include <arpa/inet.h>
33#include <netdb.h>
34
35#include <errno.h>
36#include <stdio.h>
37#include <stdlib.h>
38#include <string.h>
39#include <sys/stat.h>
40#include <sys/uio.h>
41#include <termios.h>
42#include <unistd.h>
43
44#include "layer.h"
45#include "defs.h"
46#include "mbuf.h"
47#include "log.h"
48#include "timer.h"
49#include "lqr.h"
50#include "hdlc.h"
51#include "throughput.h"
52#include "fsm.h"
53#include "lcp.h"
54#include "ccp.h"
55#include "link.h"
56#include "async.h"
57#include "descriptor.h"
58#include "physical.h"
59#include "tcp.h"
60
61static int
62tcp_OpenConnection(const char *name, char *host, char *port)
63{
64  struct sockaddr_in dest;
65  int sock;
66  struct servent *sp;
67
68  dest.sin_family = AF_INET;
69  dest.sin_addr = GetIpAddr(host);
70  if (dest.sin_addr.s_addr == INADDR_NONE) {
71    log_Printf(LogWARN, "%s: %s: unknown host\n", name, host);
72    return -2;
73  }
74  dest.sin_port = htons(atoi(port));
75  if (dest.sin_port == 0) {
76    sp = getservbyname(port, "tcp");
77    if (sp)
78      dest.sin_port = sp->s_port;
79    else {
80      log_Printf(LogWARN, "%s: %s: unknown service\n", name, port);
81      return -2;
82    }
83  }
84  log_Printf(LogPHASE, "%s: Connecting to %s:%s/tcp\n", name, host, port);
85
86  sock = socket(PF_INET, SOCK_STREAM, 0);
87  if (sock < 0)
88    return -2;
89
90  if (connect(sock, (struct sockaddr *)&dest, sizeof dest) < 0) {
91    log_Printf(LogWARN, "%s: connect: %s\n", name, strerror(errno));
92    close(sock);
93    return -2;
94  }
95
96  return sock;
97}
98
99static struct device tcpdevice = {
100  TCP_DEVICE,
101  "tcp",
102  0,
103  { CD_NOTREQUIRED, 0 },
104  NULL,
105  NULL,
106  NULL,
107  NULL,
108  NULL,
109  NULL,
110  NULL,
111  NULL,
112  NULL,
113  NULL,
114  NULL,
115  NULL,
116  NULL,
117  NULL
118};
119
120struct device *
121tcp_iov2device(int type, struct physical *p, struct iovec *iov,
122               int *niov, int maxiov __unused, int *auxfd __unused,
123	       int *nauxfd __unused)
124{
125  if (type == TCP_DEVICE) {
126    free(iov[(*niov)++].iov_base);
127    physical_SetupStack(p, tcpdevice.name, PHYSICAL_FORCE_ASYNC);
128    return &tcpdevice;
129  }
130
131  return NULL;
132}
133
134struct device *
135tcp_Create(struct physical *p)
136{
137  char *cp, *host, *port, *svc;
138
139  if (p->fd < 0) {
140    if ((cp = strchr(p->name.full, ':')) != NULL && !strchr(cp + 1, ':')) {
141      *cp = '\0';
142      host = p->name.full;
143      port = cp + 1;
144      svc = strchr(port, '/');
145      if (svc && strcasecmp(svc, "/tcp")) {
146        *cp = ':';
147        return 0;
148      }
149      if (svc) {
150        p->fd--;     /* We own the device but maybe can't use it - change fd */
151        *svc = '\0';
152      }
153      if (*host && *port) {
154        p->fd = tcp_OpenConnection(p->link.name, host, port);
155        *cp = ':';
156        if (svc)
157          *svc = '/';
158        if (p->fd >= 0)
159          log_Printf(LogDEBUG, "%s: Opened tcp socket %s\n", p->link.name,
160                     p->name.full);
161      } else {
162        if (svc)
163          *svc = '/';
164        *cp = ':';
165      }
166    }
167  }
168
169  if (p->fd >= 0) {
170    /* See if we're a tcp socket */
171    struct stat st;
172
173    if (fstat(p->fd, &st) != -1 && (st.st_mode & S_IFSOCK)) {
174      int type, sz;
175
176      sz = sizeof type;
177      if (getsockopt(p->fd, SOL_SOCKET, SO_TYPE, &type, &sz) == -1) {
178        log_Printf(LogPHASE, "%s: Link is a closed socket !\n", p->link.name);
179        close(p->fd);
180        p->fd = -1;
181        return NULL;
182      }
183
184      if (sz == sizeof type && type == SOCK_STREAM) {
185        struct sockaddr_in sock;
186        struct sockaddr *sockp = (struct sockaddr *)&sock;
187
188        if (*p->name.full == '\0') {
189          sz = sizeof sock;
190          if (getpeername(p->fd, sockp, &sz) != 0 ||
191              sz != sizeof(struct sockaddr_in) || sock.sin_family != AF_INET) {
192            log_Printf(LogDEBUG, "%s: Link is SOCK_STREAM, but not inet\n",
193                       p->link.name);
194            return NULL;
195          }
196
197          log_Printf(LogPHASE, "%s: Link is a tcp socket\n", p->link.name);
198
199          snprintf(p->name.full, sizeof p->name.full, "%s:%d/tcp",
200                   inet_ntoa(sock.sin_addr), ntohs(sock.sin_port));
201          p->name.base = p->name.full;
202        }
203        physical_SetupStack(p, tcpdevice.name, PHYSICAL_FORCE_ASYNC);
204        if (p->cfg.cd.necessity != CD_DEFAULT)
205          log_Printf(LogWARN, "Carrier settings ignored\n");
206        return &tcpdevice;
207      }
208    }
209  }
210
211  return NULL;
212}
213