mirror of git://anongit.mindrot.org/openssh.git
1665 lines
40 KiB
C
1665 lines
40 KiB
C
/* $OpenBSD: netcat.c,v 1.126 2014/10/30 16:08:31 tedu Exp $ */
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/*
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* Copyright (c) 2001 Eric Jackson <ericj@monkey.org>
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*
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* Redistribution and use in source and binary forms, with or without
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* modification, are permitted provided that the following conditions
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* are met:
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*
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* 1. Redistributions of source code must retain the above copyright
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* notice, this list of conditions and the following disclaimer.
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* 2. Redistributions in binary form must reproduce the above copyright
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* notice, this list of conditions and the following disclaimer in the
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* documentation and/or other materials provided with the distribution.
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* 3. The name of the author may not be used to endorse or promote products
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* derived from this software without specific prior written permission.
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*
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* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
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* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
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* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
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* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
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* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
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* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
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* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
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* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
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* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
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* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
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*/
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/*
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* Re-written nc(1) for OpenBSD. Original implementation by
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* *Hobbit* <hobbit@avian.org>.
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*/
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#include "includes.h"
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#include <sys/types.h>
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#include <sys/socket.h>
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#include <sys/time.h>
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#include <sys/uio.h>
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#include <sys/un.h>
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#include <netinet/in.h>
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#include <netinet/tcp.h>
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#include <netinet/ip.h>
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#include <errno.h>
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#include <netdb.h>
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#include <stdarg.h>
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#include <stdio.h>
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#include <stdlib.h>
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#include <string.h>
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#include <unistd.h>
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#include <fcntl.h>
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#include <limits.h>
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#include "atomicio.h"
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#ifdef HAVE_POLL_H
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#include <poll.h>
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#else
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# ifdef HAVE_SYS_POLL_H
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# include <sys/poll.h>
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# endif
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#endif
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#ifdef HAVE_ERR_H
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# include <err.h>
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#endif
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/* Telnet options from arpa/telnet.h */
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#define IAC 255
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#define DONT 254
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#define DO 253
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#define WONT 252
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#define WILL 251
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#ifndef SUN_LEN
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#define SUN_LEN(su) \
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(sizeof(*(su)) - sizeof((su)->sun_path) + strlen((su)->sun_path))
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#endif
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#define PORT_MAX 65535
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#define PORT_MAX_LEN 6
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#define UNIX_DG_TMP_SOCKET_SIZE 19
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#define POLL_STDIN 0
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#define POLL_NETOUT 1
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#define POLL_NETIN 2
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#define POLL_STDOUT 3
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#define BUFSIZE 16384
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/* Command Line Options */
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int dflag; /* detached, no stdin */
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int Fflag; /* fdpass sock to stdout */
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unsigned int iflag; /* Interval Flag */
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int kflag; /* More than one connect */
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int lflag; /* Bind to local port */
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int Nflag; /* shutdown() network socket */
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int nflag; /* Don't do name look up */
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char *Pflag; /* Proxy username */
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char *pflag; /* Localport flag */
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int rflag; /* Random ports flag */
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char *sflag; /* Source Address */
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int tflag; /* Telnet Emulation */
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int uflag; /* UDP - Default to TCP */
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int vflag; /* Verbosity */
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int xflag; /* Socks proxy */
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int zflag; /* Port Scan Flag */
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int Dflag; /* sodebug */
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int Iflag; /* TCP receive buffer size */
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int Oflag; /* TCP send buffer size */
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int Sflag; /* TCP MD5 signature option */
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int Tflag = -1; /* IP Type of Service */
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int rtableid = -1;
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int timeout = -1;
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int family = AF_UNSPEC;
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char *portlist[PORT_MAX+1];
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char *unix_dg_tmp_socket;
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void atelnet(int, unsigned char *, unsigned int);
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void build_ports(char *);
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void help(void);
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int local_listen(char *, char *, struct addrinfo);
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void readwrite(int);
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void fdpass(int nfd) __attribute__((noreturn));
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int remote_connect(const char *, const char *, struct addrinfo);
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int timeout_connect(int, const struct sockaddr *, socklen_t);
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int socks_connect(const char *, const char *, struct addrinfo,
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const char *, const char *, struct addrinfo, int, const char *);
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int udptest(int);
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int unix_bind(char *);
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int unix_connect(char *);
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int unix_listen(char *);
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void set_common_sockopts(int);
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int map_tos(char *, int *);
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void report_connect(const struct sockaddr *, socklen_t);
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void usage(int);
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ssize_t drainbuf(int, unsigned char *, size_t *);
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ssize_t fillbuf(int, unsigned char *, size_t *);
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int
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main(int argc, char *argv[])
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{
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int ch, s, ret, socksv;
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char *host, *uport;
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struct addrinfo hints;
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struct servent *sv;
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socklen_t len;
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struct sockaddr_storage cliaddr;
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char *proxy = NULL;
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const char *errstr, *proxyhost = "", *proxyport = NULL;
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struct addrinfo proxyhints;
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char unix_dg_tmp_socket_buf[UNIX_DG_TMP_SOCKET_SIZE];
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ret = 1;
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s = 0;
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socksv = 5;
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host = NULL;
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uport = NULL;
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sv = NULL;
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while ((ch = getopt(argc, argv,
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"46DdFhI:i:klNnO:P:p:rSs:tT:UuV:vw:X:x:z")) != -1) {
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switch (ch) {
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case '4':
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family = AF_INET;
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break;
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case '6':
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family = AF_INET6;
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break;
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case 'U':
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family = AF_UNIX;
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break;
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case 'X':
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if (strcasecmp(optarg, "connect") == 0)
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socksv = -1; /* HTTP proxy CONNECT */
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else if (strcmp(optarg, "4") == 0)
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socksv = 4; /* SOCKS v.4 */
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else if (strcmp(optarg, "5") == 0)
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socksv = 5; /* SOCKS v.5 */
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else
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errx(1, "unsupported proxy protocol");
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break;
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case 'd':
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dflag = 1;
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break;
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case 'F':
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Fflag = 1;
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break;
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case 'h':
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help();
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break;
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case 'i':
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iflag = strtonum(optarg, 0, UINT_MAX, &errstr);
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if (errstr)
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errx(1, "interval %s: %s", errstr, optarg);
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break;
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case 'k':
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kflag = 1;
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break;
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case 'l':
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lflag = 1;
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break;
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case 'N':
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Nflag = 1;
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break;
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case 'n':
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nflag = 1;
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break;
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case 'P':
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Pflag = optarg;
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break;
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case 'p':
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pflag = optarg;
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break;
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case 'r':
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rflag = 1;
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break;
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case 's':
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sflag = optarg;
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break;
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case 't':
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tflag = 1;
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break;
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case 'u':
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uflag = 1;
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break;
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#ifdef SO_RTABLE
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case 'V':
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rtableid = (int)strtonum(optarg, 0,
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RT_TABLEID_MAX, &errstr);
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if (errstr)
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errx(1, "rtable %s: %s", errstr, optarg);
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break;
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#endif
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case 'v':
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vflag = 1;
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break;
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case 'w':
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timeout = strtonum(optarg, 0, INT_MAX / 1000, &errstr);
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if (errstr)
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errx(1, "timeout %s: %s", errstr, optarg);
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timeout *= 1000;
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break;
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case 'x':
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xflag = 1;
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if ((proxy = strdup(optarg)) == NULL)
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errx(1, "strdup");
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break;
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case 'z':
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zflag = 1;
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break;
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case 'D':
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Dflag = 1;
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break;
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case 'I':
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Iflag = strtonum(optarg, 1, 65536 << 14, &errstr);
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if (errstr != NULL)
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errx(1, "TCP receive window %s: %s",
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errstr, optarg);
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break;
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case 'O':
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Oflag = strtonum(optarg, 1, 65536 << 14, &errstr);
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if (errstr != NULL)
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errx(1, "TCP send window %s: %s",
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errstr, optarg);
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break;
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case 'S':
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Sflag = 1;
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break;
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case 'T':
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errstr = NULL;
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errno = 0;
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if (map_tos(optarg, &Tflag))
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break;
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if (strlen(optarg) > 1 && optarg[0] == '0' &&
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optarg[1] == 'x')
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Tflag = (int)strtol(optarg, NULL, 16);
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else
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Tflag = (int)strtonum(optarg, 0, 255,
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&errstr);
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if (Tflag < 0 || Tflag > 255 || errstr || errno)
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errx(1, "illegal tos value %s", optarg);
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break;
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default:
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usage(1);
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}
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}
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argc -= optind;
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argv += optind;
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/* Cruft to make sure options are clean, and used properly. */
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if (argv[0] && !argv[1] && family == AF_UNIX) {
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host = argv[0];
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uport = NULL;
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} else if (argv[0] && !argv[1]) {
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if (!lflag)
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usage(1);
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uport = argv[0];
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host = NULL;
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} else if (argv[0] && argv[1]) {
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host = argv[0];
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uport = argv[1];
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} else
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usage(1);
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if (lflag && sflag)
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errx(1, "cannot use -s and -l");
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if (lflag && pflag)
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errx(1, "cannot use -p and -l");
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if (lflag && zflag)
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errx(1, "cannot use -z and -l");
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if (!lflag && kflag)
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errx(1, "must use -l with -k");
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/* Get name of temporary socket for unix datagram client */
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if ((family == AF_UNIX) && uflag && !lflag) {
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if (sflag) {
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unix_dg_tmp_socket = sflag;
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} else {
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strlcpy(unix_dg_tmp_socket_buf, "/tmp/nc.XXXXXXXXXX",
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UNIX_DG_TMP_SOCKET_SIZE);
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if (mktemp(unix_dg_tmp_socket_buf) == NULL)
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err(1, "mktemp");
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unix_dg_tmp_socket = unix_dg_tmp_socket_buf;
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}
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}
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/* Initialize addrinfo structure. */
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if (family != AF_UNIX) {
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memset(&hints, 0, sizeof(struct addrinfo));
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hints.ai_family = family;
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hints.ai_socktype = uflag ? SOCK_DGRAM : SOCK_STREAM;
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hints.ai_protocol = uflag ? IPPROTO_UDP : IPPROTO_TCP;
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if (nflag)
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hints.ai_flags |= AI_NUMERICHOST;
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}
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if (xflag) {
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if (uflag)
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errx(1, "no proxy support for UDP mode");
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if (lflag)
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errx(1, "no proxy support for listen");
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if (family == AF_UNIX)
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errx(1, "no proxy support for unix sockets");
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/* XXX IPv6 transport to proxy would probably work */
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if (family == AF_INET6)
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errx(1, "no proxy support for IPv6");
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if (sflag)
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errx(1, "no proxy support for local source address");
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proxyhost = strsep(&proxy, ":");
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proxyport = proxy;
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memset(&proxyhints, 0, sizeof(struct addrinfo));
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proxyhints.ai_family = family;
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proxyhints.ai_socktype = SOCK_STREAM;
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proxyhints.ai_protocol = IPPROTO_TCP;
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if (nflag)
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proxyhints.ai_flags |= AI_NUMERICHOST;
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}
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if (lflag) {
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int connfd;
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ret = 0;
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if (family == AF_UNIX) {
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if (uflag)
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s = unix_bind(host);
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else
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s = unix_listen(host);
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}
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/* Allow only one connection at a time, but stay alive. */
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for (;;) {
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if (family != AF_UNIX)
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s = local_listen(host, uport, hints);
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if (s < 0)
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err(1, "local_listen");
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/*
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* For UDP and -k, don't connect the socket, let it
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* receive datagrams from multiple socket pairs.
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*/
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if (uflag && kflag)
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readwrite(s);
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/*
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* For UDP and not -k, we will use recvfrom() initially
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* to wait for a caller, then use the regular functions
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* to talk to the caller.
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*/
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else if (uflag && !kflag) {
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int rv, plen;
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char buf[16384];
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struct sockaddr_storage z;
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len = sizeof(z);
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plen = 2048;
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rv = recvfrom(s, buf, plen, MSG_PEEK,
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(struct sockaddr *)&z, &len);
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if (rv < 0)
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err(1, "recvfrom");
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rv = connect(s, (struct sockaddr *)&z, len);
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if (rv < 0)
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err(1, "connect");
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if (vflag)
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report_connect((struct sockaddr *)&z, len);
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readwrite(s);
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} else {
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len = sizeof(cliaddr);
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connfd = accept(s, (struct sockaddr *)&cliaddr,
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&len);
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if (connfd == -1) {
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/* For now, all errnos are fatal */
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err(1, "accept");
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}
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if (vflag)
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report_connect((struct sockaddr *)&cliaddr, len);
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readwrite(connfd);
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close(connfd);
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}
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if (family != AF_UNIX)
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close(s);
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else if (uflag) {
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if (connect(s, NULL, 0) < 0)
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err(1, "connect");
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}
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if (!kflag)
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break;
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}
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} else if (family == AF_UNIX) {
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ret = 0;
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if ((s = unix_connect(host)) > 0 && !zflag) {
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readwrite(s);
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close(s);
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} else
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ret = 1;
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if (uflag)
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unlink(unix_dg_tmp_socket);
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exit(ret);
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} else {
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int i = 0;
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/* Construct the portlist[] array. */
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build_ports(uport);
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/* Cycle through portlist, connecting to each port. */
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for (i = 0; portlist[i] != NULL; i++) {
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if (s)
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close(s);
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if (xflag)
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s = socks_connect(host, portlist[i], hints,
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proxyhost, proxyport, proxyhints, socksv,
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Pflag);
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else
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s = remote_connect(host, portlist[i], hints);
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if (s < 0)
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continue;
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ret = 0;
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if (vflag || zflag) {
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/* For UDP, make sure we are connected. */
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if (uflag) {
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if (udptest(s) == -1) {
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ret = 1;
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continue;
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}
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}
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/* Don't look up port if -n. */
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if (nflag)
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sv = NULL;
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else {
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sv = getservbyport(
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ntohs(atoi(portlist[i])),
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uflag ? "udp" : "tcp");
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}
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|
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fprintf(stderr,
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"Connection to %s %s port [%s/%s] "
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"succeeded!\n", host, portlist[i],
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uflag ? "udp" : "tcp",
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sv ? sv->s_name : "*");
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}
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if (Fflag)
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fdpass(s);
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else if (!zflag)
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readwrite(s);
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}
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}
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|
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if (s)
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close(s);
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|
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exit(ret);
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}
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|
|
/*
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* unix_bind()
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* Returns a unix socket bound to the given path
|
|
*/
|
|
int
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unix_bind(char *path)
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|
{
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|
struct sockaddr_un sun_sa;
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int s;
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|
|
/* Create unix domain socket. */
|
|
if ((s = socket(AF_UNIX, uflag ? SOCK_DGRAM : SOCK_STREAM,
|
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0)) < 0)
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return (-1);
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|
|
memset(&sun_sa, 0, sizeof(struct sockaddr_un));
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|
sun_sa.sun_family = AF_UNIX;
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|
|
if (strlcpy(sun_sa.sun_path, path, sizeof(sun_sa.sun_path)) >=
|
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sizeof(sun_sa.sun_path)) {
|
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close(s);
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errno = ENAMETOOLONG;
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return (-1);
|
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}
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|
|
if (bind(s, (struct sockaddr *)&sun_sa, SUN_LEN(&sun_sa)) < 0) {
|
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close(s);
|
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return (-1);
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|
}
|
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return (s);
|
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}
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|
|
/*
|
|
* unix_connect()
|
|
* Returns a socket connected to a local unix socket. Returns -1 on failure.
|
|
*/
|
|
int
|
|
unix_connect(char *path)
|
|
{
|
|
struct sockaddr_un sun_sa;
|
|
int s;
|
|
|
|
if (uflag) {
|
|
if ((s = unix_bind(unix_dg_tmp_socket)) < 0)
|
|
return (-1);
|
|
} else {
|
|
if ((s = socket(AF_UNIX, SOCK_STREAM, 0)) < 0)
|
|
return (-1);
|
|
}
|
|
(void)fcntl(s, F_SETFD, FD_CLOEXEC);
|
|
|
|
memset(&sun_sa, 0, sizeof(struct sockaddr_un));
|
|
sun_sa.sun_family = AF_UNIX;
|
|
|
|
if (strlcpy(sun_sa.sun_path, path, sizeof(sun_sa.sun_path)) >=
|
|
sizeof(sun_sa.sun_path)) {
|
|
close(s);
|
|
errno = ENAMETOOLONG;
|
|
return (-1);
|
|
}
|
|
if (connect(s, (struct sockaddr *)&sun_sa, SUN_LEN(&sun_sa)) < 0) {
|
|
close(s);
|
|
return (-1);
|
|
}
|
|
return (s);
|
|
|
|
}
|
|
|
|
/*
|
|
* unix_listen()
|
|
* Create a unix domain socket, and listen on it.
|
|
*/
|
|
int
|
|
unix_listen(char *path)
|
|
{
|
|
int s;
|
|
if ((s = unix_bind(path)) < 0)
|
|
return (-1);
|
|
|
|
if (listen(s, 5) < 0) {
|
|
close(s);
|
|
return (-1);
|
|
}
|
|
return (s);
|
|
}
|
|
|
|
/*
|
|
* remote_connect()
|
|
* Returns a socket connected to a remote host. Properly binds to a local
|
|
* port or source address if needed. Returns -1 on failure.
|
|
*/
|
|
int
|
|
remote_connect(const char *host, const char *port, struct addrinfo hints)
|
|
{
|
|
struct addrinfo *res, *res0;
|
|
int s, error;
|
|
#if defined(SO_RTABLE) || defined(SO_BINDANY)
|
|
int on = 1;
|
|
#endif
|
|
|
|
if ((error = getaddrinfo(host, port, &hints, &res)))
|
|
errx(1, "getaddrinfo: %s", gai_strerror(error));
|
|
|
|
res0 = res;
|
|
do {
|
|
if ((s = socket(res0->ai_family, res0->ai_socktype,
|
|
res0->ai_protocol)) < 0)
|
|
continue;
|
|
|
|
#ifdef SO_RTABLE
|
|
if (rtableid >= 0 && (setsockopt(s, SOL_SOCKET, SO_RTABLE,
|
|
&rtableid, sizeof(rtableid)) == -1))
|
|
err(1, "setsockopt SO_RTABLE");
|
|
#endif
|
|
/* Bind to a local port or source address if specified. */
|
|
if (sflag || pflag) {
|
|
struct addrinfo ahints, *ares;
|
|
|
|
#ifdef SO_BINDANY
|
|
/* try SO_BINDANY, but don't insist */
|
|
setsockopt(s, SOL_SOCKET, SO_BINDANY, &on, sizeof(on));
|
|
#endif
|
|
memset(&ahints, 0, sizeof(struct addrinfo));
|
|
ahints.ai_family = res0->ai_family;
|
|
ahints.ai_socktype = uflag ? SOCK_DGRAM : SOCK_STREAM;
|
|
ahints.ai_protocol = uflag ? IPPROTO_UDP : IPPROTO_TCP;
|
|
ahints.ai_flags = AI_PASSIVE;
|
|
if ((error = getaddrinfo(sflag, pflag, &ahints, &ares)))
|
|
errx(1, "getaddrinfo: %s", gai_strerror(error));
|
|
|
|
if (bind(s, (struct sockaddr *)ares->ai_addr,
|
|
ares->ai_addrlen) < 0)
|
|
err(1, "bind failed");
|
|
freeaddrinfo(ares);
|
|
}
|
|
|
|
set_common_sockopts(s);
|
|
|
|
if (timeout_connect(s, res0->ai_addr, res0->ai_addrlen) == 0)
|
|
break;
|
|
else if (vflag)
|
|
warn("connect to %s port %s (%s) failed", host, port,
|
|
uflag ? "udp" : "tcp");
|
|
|
|
close(s);
|
|
s = -1;
|
|
} while ((res0 = res0->ai_next) != NULL);
|
|
|
|
freeaddrinfo(res);
|
|
|
|
return (s);
|
|
}
|
|
|
|
int
|
|
timeout_connect(int s, const struct sockaddr *name, socklen_t namelen)
|
|
{
|
|
struct pollfd pfd;
|
|
socklen_t optlen;
|
|
int flags = 0, optval;
|
|
int ret;
|
|
|
|
if (timeout != -1) {
|
|
flags = fcntl(s, F_GETFL, 0);
|
|
if (fcntl(s, F_SETFL, flags | O_NONBLOCK) == -1)
|
|
err(1, "set non-blocking mode");
|
|
}
|
|
|
|
if ((ret = connect(s, name, namelen)) != 0 && errno == EINPROGRESS) {
|
|
pfd.fd = s;
|
|
pfd.events = POLLOUT;
|
|
if ((ret = poll(&pfd, 1, timeout)) == 1) {
|
|
optlen = sizeof(optval);
|
|
if ((ret = getsockopt(s, SOL_SOCKET, SO_ERROR,
|
|
&optval, &optlen)) == 0) {
|
|
errno = optval;
|
|
ret = optval == 0 ? 0 : -1;
|
|
}
|
|
} else if (ret == 0) {
|
|
errno = ETIMEDOUT;
|
|
ret = -1;
|
|
} else
|
|
err(1, "poll failed");
|
|
}
|
|
|
|
if (timeout != -1 && fcntl(s, F_SETFL, flags) == -1)
|
|
err(1, "restoring flags");
|
|
|
|
return (ret);
|
|
}
|
|
|
|
/*
|
|
* local_listen()
|
|
* Returns a socket listening on a local port, binds to specified source
|
|
* address. Returns -1 on failure.
|
|
*/
|
|
int
|
|
local_listen(char *host, char *port, struct addrinfo hints)
|
|
{
|
|
struct addrinfo *res, *res0;
|
|
int s, ret, x = 1;
|
|
int error;
|
|
|
|
/* Allow nodename to be null. */
|
|
hints.ai_flags |= AI_PASSIVE;
|
|
|
|
/*
|
|
* In the case of binding to a wildcard address
|
|
* default to binding to an ipv4 address.
|
|
*/
|
|
if (host == NULL && hints.ai_family == AF_UNSPEC)
|
|
hints.ai_family = AF_INET;
|
|
|
|
if ((error = getaddrinfo(host, port, &hints, &res)))
|
|
errx(1, "getaddrinfo: %s", gai_strerror(error));
|
|
|
|
res0 = res;
|
|
do {
|
|
if ((s = socket(res0->ai_family, res0->ai_socktype,
|
|
res0->ai_protocol)) < 0)
|
|
continue;
|
|
|
|
#ifdef SO_RTABLE
|
|
if (rtableid >= 0 && (setsockopt(s, SOL_SOCKET, SO_RTABLE,
|
|
&rtableid, sizeof(rtableid)) == -1))
|
|
err(1, "setsockopt SO_RTABLE");
|
|
#endif
|
|
#ifdef SO_REUSEPORT
|
|
ret = setsockopt(s, SOL_SOCKET, SO_REUSEPORT, &x, sizeof(x));
|
|
if (ret == -1)
|
|
err(1, "setsockopt SO_REUSEPORT");
|
|
#endif
|
|
#ifdef SO_REUSEADDR
|
|
ret = setsockopt(s, SOL_SOCKET, SO_REUSEADDR, &x, sizeof(x));
|
|
if (ret == -1)
|
|
err(1, "setsockopt SO_REUSEADDR");
|
|
#endif
|
|
set_common_sockopts(s);
|
|
|
|
if (bind(s, (struct sockaddr *)res0->ai_addr,
|
|
res0->ai_addrlen) == 0)
|
|
break;
|
|
|
|
close(s);
|
|
s = -1;
|
|
} while ((res0 = res0->ai_next) != NULL);
|
|
|
|
if (!uflag && s != -1) {
|
|
if (listen(s, 1) < 0)
|
|
err(1, "listen");
|
|
}
|
|
|
|
freeaddrinfo(res);
|
|
|
|
return (s);
|
|
}
|
|
|
|
/*
|
|
* readwrite()
|
|
* Loop that polls on the network file descriptor and stdin.
|
|
*/
|
|
void
|
|
readwrite(int net_fd)
|
|
{
|
|
struct pollfd pfd[4];
|
|
int stdin_fd = STDIN_FILENO;
|
|
int stdout_fd = STDOUT_FILENO;
|
|
unsigned char netinbuf[BUFSIZE];
|
|
size_t netinbufpos = 0;
|
|
unsigned char stdinbuf[BUFSIZE];
|
|
size_t stdinbufpos = 0;
|
|
int n, num_fds;
|
|
ssize_t ret;
|
|
|
|
/* don't read from stdin if requested */
|
|
if (dflag)
|
|
stdin_fd = -1;
|
|
|
|
/* stdin */
|
|
pfd[POLL_STDIN].fd = stdin_fd;
|
|
pfd[POLL_STDIN].events = POLLIN;
|
|
|
|
/* network out */
|
|
pfd[POLL_NETOUT].fd = net_fd;
|
|
pfd[POLL_NETOUT].events = 0;
|
|
|
|
/* network in */
|
|
pfd[POLL_NETIN].fd = net_fd;
|
|
pfd[POLL_NETIN].events = POLLIN;
|
|
|
|
/* stdout */
|
|
pfd[POLL_STDOUT].fd = stdout_fd;
|
|
pfd[POLL_STDOUT].events = 0;
|
|
|
|
while (1) {
|
|
/* both inputs are gone, buffers are empty, we are done */
|
|
if (pfd[POLL_STDIN].fd == -1 && pfd[POLL_NETIN].fd == -1
|
|
&& stdinbufpos == 0 && netinbufpos == 0) {
|
|
close(net_fd);
|
|
return;
|
|
}
|
|
/* both outputs are gone, we can't continue */
|
|
if (pfd[POLL_NETOUT].fd == -1 && pfd[POLL_STDOUT].fd == -1) {
|
|
close(net_fd);
|
|
return;
|
|
}
|
|
/* listen and net in gone, queues empty, done */
|
|
if (lflag && pfd[POLL_NETIN].fd == -1
|
|
&& stdinbufpos == 0 && netinbufpos == 0) {
|
|
close(net_fd);
|
|
return;
|
|
}
|
|
|
|
/* help says -i is for "wait between lines sent". We read and
|
|
* write arbitrary amounts of data, and we don't want to start
|
|
* scanning for newlines, so this is as good as it gets */
|
|
if (iflag)
|
|
sleep(iflag);
|
|
|
|
/* poll */
|
|
num_fds = poll(pfd, 4, timeout);
|
|
|
|
/* treat poll errors */
|
|
if (num_fds == -1) {
|
|
close(net_fd);
|
|
err(1, "polling error");
|
|
}
|
|
|
|
/* timeout happened */
|
|
if (num_fds == 0)
|
|
return;
|
|
|
|
/* treat socket error conditions */
|
|
for (n = 0; n < 4; n++) {
|
|
if (pfd[n].revents & (POLLERR|POLLNVAL)) {
|
|
pfd[n].fd = -1;
|
|
}
|
|
}
|
|
/* reading is possible after HUP */
|
|
if (pfd[POLL_STDIN].events & POLLIN &&
|
|
pfd[POLL_STDIN].revents & POLLHUP &&
|
|
! (pfd[POLL_STDIN].revents & POLLIN))
|
|
pfd[POLL_STDIN].fd = -1;
|
|
|
|
if (pfd[POLL_NETIN].events & POLLIN &&
|
|
pfd[POLL_NETIN].revents & POLLHUP &&
|
|
! (pfd[POLL_NETIN].revents & POLLIN))
|
|
pfd[POLL_NETIN].fd = -1;
|
|
|
|
if (pfd[POLL_NETOUT].revents & POLLHUP) {
|
|
if (Nflag)
|
|
shutdown(pfd[POLL_NETOUT].fd, SHUT_WR);
|
|
pfd[POLL_NETOUT].fd = -1;
|
|
}
|
|
/* if HUP, stop watching stdout */
|
|
if (pfd[POLL_STDOUT].revents & POLLHUP)
|
|
pfd[POLL_STDOUT].fd = -1;
|
|
/* if no net out, stop watching stdin */
|
|
if (pfd[POLL_NETOUT].fd == -1)
|
|
pfd[POLL_STDIN].fd = -1;
|
|
/* if no stdout, stop watching net in */
|
|
if (pfd[POLL_STDOUT].fd == -1) {
|
|
if (pfd[POLL_NETIN].fd != -1)
|
|
shutdown(pfd[POLL_NETIN].fd, SHUT_RD);
|
|
pfd[POLL_NETIN].fd = -1;
|
|
}
|
|
|
|
/* try to read from stdin */
|
|
if (pfd[POLL_STDIN].revents & POLLIN && stdinbufpos < BUFSIZE) {
|
|
ret = fillbuf(pfd[POLL_STDIN].fd, stdinbuf,
|
|
&stdinbufpos);
|
|
/* error or eof on stdin - remove from pfd */
|
|
if (ret == 0 || ret == -1)
|
|
pfd[POLL_STDIN].fd = -1;
|
|
/* read something - poll net out */
|
|
if (stdinbufpos > 0)
|
|
pfd[POLL_NETOUT].events = POLLOUT;
|
|
/* filled buffer - remove self from polling */
|
|
if (stdinbufpos == BUFSIZE)
|
|
pfd[POLL_STDIN].events = 0;
|
|
}
|
|
/* try to write to network */
|
|
if (pfd[POLL_NETOUT].revents & POLLOUT && stdinbufpos > 0) {
|
|
ret = drainbuf(pfd[POLL_NETOUT].fd, stdinbuf,
|
|
&stdinbufpos);
|
|
if (ret == -1)
|
|
pfd[POLL_NETOUT].fd = -1;
|
|
/* buffer empty - remove self from polling */
|
|
if (stdinbufpos == 0)
|
|
pfd[POLL_NETOUT].events = 0;
|
|
/* buffer no longer full - poll stdin again */
|
|
if (stdinbufpos < BUFSIZE)
|
|
pfd[POLL_STDIN].events = POLLIN;
|
|
}
|
|
/* try to read from network */
|
|
if (pfd[POLL_NETIN].revents & POLLIN && netinbufpos < BUFSIZE) {
|
|
ret = fillbuf(pfd[POLL_NETIN].fd, netinbuf,
|
|
&netinbufpos);
|
|
if (ret == -1)
|
|
pfd[POLL_NETIN].fd = -1;
|
|
/* eof on net in - remove from pfd */
|
|
if (ret == 0) {
|
|
shutdown(pfd[POLL_NETIN].fd, SHUT_RD);
|
|
pfd[POLL_NETIN].fd = -1;
|
|
}
|
|
/* read something - poll stdout */
|
|
if (netinbufpos > 0)
|
|
pfd[POLL_STDOUT].events = POLLOUT;
|
|
/* filled buffer - remove self from polling */
|
|
if (netinbufpos == BUFSIZE)
|
|
pfd[POLL_NETIN].events = 0;
|
|
/* handle telnet */
|
|
if (tflag)
|
|
atelnet(pfd[POLL_NETIN].fd, netinbuf,
|
|
netinbufpos);
|
|
}
|
|
/* try to write to stdout */
|
|
if (pfd[POLL_STDOUT].revents & POLLOUT && netinbufpos > 0) {
|
|
ret = drainbuf(pfd[POLL_STDOUT].fd, netinbuf,
|
|
&netinbufpos);
|
|
if (ret == -1)
|
|
pfd[POLL_STDOUT].fd = -1;
|
|
/* buffer empty - remove self from polling */
|
|
if (netinbufpos == 0)
|
|
pfd[POLL_STDOUT].events = 0;
|
|
/* buffer no longer full - poll net in again */
|
|
if (netinbufpos < BUFSIZE)
|
|
pfd[POLL_NETIN].events = POLLIN;
|
|
}
|
|
|
|
/* stdin gone and queue empty? */
|
|
if (pfd[POLL_STDIN].fd == -1 && stdinbufpos == 0) {
|
|
if (pfd[POLL_NETOUT].fd != -1 && Nflag)
|
|
shutdown(pfd[POLL_NETOUT].fd, SHUT_WR);
|
|
pfd[POLL_NETOUT].fd = -1;
|
|
}
|
|
/* net in gone and queue empty? */
|
|
if (pfd[POLL_NETIN].fd == -1 && netinbufpos == 0) {
|
|
pfd[POLL_STDOUT].fd = -1;
|
|
}
|
|
}
|
|
}
|
|
|
|
ssize_t
|
|
drainbuf(int fd, unsigned char *buf, size_t *bufpos)
|
|
{
|
|
ssize_t n;
|
|
ssize_t adjust;
|
|
|
|
n = write(fd, buf, *bufpos);
|
|
/* don't treat EAGAIN, EINTR as error */
|
|
if (n == -1 && (errno == EAGAIN || errno == EINTR))
|
|
n = -2;
|
|
if (n <= 0)
|
|
return n;
|
|
/* adjust buffer */
|
|
adjust = *bufpos - n;
|
|
if (adjust > 0)
|
|
memmove(buf, buf + n, adjust);
|
|
*bufpos -= n;
|
|
return n;
|
|
}
|
|
|
|
|
|
ssize_t
|
|
fillbuf(int fd, unsigned char *buf, size_t *bufpos)
|
|
{
|
|
size_t num = BUFSIZE - *bufpos;
|
|
ssize_t n;
|
|
|
|
n = read(fd, buf + *bufpos, num);
|
|
/* don't treat EAGAIN, EINTR as error */
|
|
if (n == -1 && (errno == EAGAIN || errno == EINTR))
|
|
n = -2;
|
|
if (n <= 0)
|
|
return n;
|
|
*bufpos += n;
|
|
return n;
|
|
}
|
|
|
|
/*
|
|
* fdpass()
|
|
* Pass the connected file descriptor to stdout and exit.
|
|
*/
|
|
void
|
|
fdpass(int nfd)
|
|
{
|
|
#if defined(HAVE_SENDMSG) && (defined(HAVE_ACCRIGHTS_IN_MSGHDR) || defined(HAVE_CONTROL_IN_MSGHDR))
|
|
struct msghdr msg;
|
|
#ifndef HAVE_ACCRIGHTS_IN_MSGHDR
|
|
union {
|
|
struct cmsghdr hdr;
|
|
char buf[CMSG_SPACE(sizeof(int))];
|
|
} cmsgbuf;
|
|
struct cmsghdr *cmsg;
|
|
#endif
|
|
struct iovec vec;
|
|
char ch = '\0';
|
|
struct pollfd pfd;
|
|
ssize_t r;
|
|
|
|
memset(&msg, 0, sizeof(msg));
|
|
#ifdef HAVE_ACCRIGHTS_IN_MSGHDR
|
|
msg.msg_accrights = (caddr_t)&nfd;
|
|
msg.msg_accrightslen = sizeof(nfd);
|
|
#else
|
|
memset(&cmsgbuf, 0, sizeof(cmsgbuf));
|
|
msg.msg_control = (caddr_t)&cmsgbuf.buf;
|
|
msg.msg_controllen = sizeof(cmsgbuf.buf);
|
|
cmsg = CMSG_FIRSTHDR(&msg);
|
|
cmsg->cmsg_len = CMSG_LEN(sizeof(int));
|
|
cmsg->cmsg_level = SOL_SOCKET;
|
|
cmsg->cmsg_type = SCM_RIGHTS;
|
|
*(int *)CMSG_DATA(cmsg) = nfd;
|
|
#endif
|
|
|
|
vec.iov_base = &ch;
|
|
vec.iov_len = 1;
|
|
msg.msg_iov = &vec;
|
|
msg.msg_iovlen = 1;
|
|
|
|
bzero(&pfd, sizeof(pfd));
|
|
pfd.fd = STDOUT_FILENO;
|
|
for (;;) {
|
|
r = sendmsg(STDOUT_FILENO, &msg, 0);
|
|
if (r == -1) {
|
|
if (errno == EAGAIN || errno == EINTR) {
|
|
pfd.events = POLLOUT;
|
|
if (poll(&pfd, 1, -1) == -1)
|
|
err(1, "poll");
|
|
continue;
|
|
}
|
|
err(1, "sendmsg");
|
|
} else if (r == -1)
|
|
errx(1, "sendmsg: unexpected return value %zd", r);
|
|
else
|
|
break;
|
|
}
|
|
exit(0);
|
|
#else
|
|
errx(1, "%s: file descriptor passing not supported", __func__);
|
|
#endif
|
|
}
|
|
|
|
/* Deal with RFC 854 WILL/WONT DO/DONT negotiation. */
|
|
void
|
|
atelnet(int nfd, unsigned char *buf, unsigned int size)
|
|
{
|
|
unsigned char *p, *end;
|
|
unsigned char obuf[4];
|
|
|
|
if (size < 3)
|
|
return;
|
|
end = buf + size - 2;
|
|
|
|
for (p = buf; p < end; p++) {
|
|
if (*p != IAC)
|
|
continue;
|
|
|
|
obuf[0] = IAC;
|
|
p++;
|
|
if ((*p == WILL) || (*p == WONT))
|
|
obuf[1] = DONT;
|
|
else if ((*p == DO) || (*p == DONT))
|
|
obuf[1] = WONT;
|
|
else
|
|
continue;
|
|
|
|
p++;
|
|
obuf[2] = *p;
|
|
if (atomicio(vwrite, nfd, obuf, 3) != 3)
|
|
warn("Write Error!");
|
|
}
|
|
}
|
|
|
|
/*
|
|
* build_ports()
|
|
* Build an array of ports in portlist[], listing each port
|
|
* that we should try to connect to.
|
|
*/
|
|
void
|
|
build_ports(char *p)
|
|
{
|
|
const char *errstr;
|
|
char *n;
|
|
int hi, lo, cp;
|
|
int x = 0;
|
|
|
|
if ((n = strchr(p, '-')) != NULL) {
|
|
*n = '\0';
|
|
n++;
|
|
|
|
/* Make sure the ports are in order: lowest->highest. */
|
|
hi = strtonum(n, 1, PORT_MAX, &errstr);
|
|
if (errstr)
|
|
errx(1, "port number %s: %s", errstr, n);
|
|
lo = strtonum(p, 1, PORT_MAX, &errstr);
|
|
if (errstr)
|
|
errx(1, "port number %s: %s", errstr, p);
|
|
|
|
if (lo > hi) {
|
|
cp = hi;
|
|
hi = lo;
|
|
lo = cp;
|
|
}
|
|
|
|
/* Load ports sequentially. */
|
|
for (cp = lo; cp <= hi; cp++) {
|
|
portlist[x] = calloc(1, PORT_MAX_LEN);
|
|
if (portlist[x] == NULL)
|
|
errx(1, "calloc");
|
|
snprintf(portlist[x], PORT_MAX_LEN, "%d", cp);
|
|
x++;
|
|
}
|
|
|
|
/* Randomly swap ports. */
|
|
if (rflag) {
|
|
int y;
|
|
char *c;
|
|
|
|
for (x = 0; x <= (hi - lo); x++) {
|
|
y = (arc4random() & 0xFFFF) % (hi - lo);
|
|
c = portlist[x];
|
|
portlist[x] = portlist[y];
|
|
portlist[y] = c;
|
|
}
|
|
}
|
|
} else {
|
|
hi = strtonum(p, 1, PORT_MAX, &errstr);
|
|
if (errstr)
|
|
errx(1, "port number %s: %s", errstr, p);
|
|
portlist[0] = strdup(p);
|
|
if (portlist[0] == NULL)
|
|
errx(1, "strdup");
|
|
}
|
|
}
|
|
|
|
/*
|
|
* udptest()
|
|
* Do a few writes to see if the UDP port is there.
|
|
* Fails once PF state table is full.
|
|
*/
|
|
int
|
|
udptest(int s)
|
|
{
|
|
int i, ret;
|
|
|
|
for (i = 0; i <= 3; i++) {
|
|
if (write(s, "X", 1) == 1)
|
|
ret = 1;
|
|
else
|
|
ret = -1;
|
|
}
|
|
return (ret);
|
|
}
|
|
|
|
void
|
|
set_common_sockopts(int s)
|
|
{
|
|
int x = 1;
|
|
|
|
#ifdef TCP_MD5SIG
|
|
if (Sflag) {
|
|
if (setsockopt(s, IPPROTO_TCP, TCP_MD5SIG,
|
|
&x, sizeof(x)) == -1)
|
|
err(1, "setsockopt");
|
|
}
|
|
#endif
|
|
if (Dflag) {
|
|
if (setsockopt(s, SOL_SOCKET, SO_DEBUG,
|
|
&x, sizeof(x)) == -1)
|
|
err(1, "setsockopt");
|
|
}
|
|
if (Tflag != -1) {
|
|
if (setsockopt(s, IPPROTO_IP, IP_TOS,
|
|
&Tflag, sizeof(Tflag)) == -1)
|
|
err(1, "set IP ToS");
|
|
}
|
|
if (Iflag) {
|
|
if (setsockopt(s, SOL_SOCKET, SO_RCVBUF,
|
|
&Iflag, sizeof(Iflag)) == -1)
|
|
err(1, "set TCP receive buffer size");
|
|
}
|
|
if (Oflag) {
|
|
if (setsockopt(s, SOL_SOCKET, SO_SNDBUF,
|
|
&Oflag, sizeof(Oflag)) == -1)
|
|
err(1, "set TCP send buffer size");
|
|
}
|
|
}
|
|
|
|
int
|
|
map_tos(char *s, int *val)
|
|
{
|
|
/* DiffServ Codepoints and other TOS mappings */
|
|
const struct toskeywords {
|
|
const char *keyword;
|
|
int val;
|
|
} *t, toskeywords[] = {
|
|
{ "af11", IPTOS_DSCP_AF11 },
|
|
{ "af12", IPTOS_DSCP_AF12 },
|
|
{ "af13", IPTOS_DSCP_AF13 },
|
|
{ "af21", IPTOS_DSCP_AF21 },
|
|
{ "af22", IPTOS_DSCP_AF22 },
|
|
{ "af23", IPTOS_DSCP_AF23 },
|
|
{ "af31", IPTOS_DSCP_AF31 },
|
|
{ "af32", IPTOS_DSCP_AF32 },
|
|
{ "af33", IPTOS_DSCP_AF33 },
|
|
{ "af41", IPTOS_DSCP_AF41 },
|
|
{ "af42", IPTOS_DSCP_AF42 },
|
|
{ "af43", IPTOS_DSCP_AF43 },
|
|
{ "critical", IPTOS_PREC_CRITIC_ECP },
|
|
{ "cs0", IPTOS_DSCP_CS0 },
|
|
{ "cs1", IPTOS_DSCP_CS1 },
|
|
{ "cs2", IPTOS_DSCP_CS2 },
|
|
{ "cs3", IPTOS_DSCP_CS3 },
|
|
{ "cs4", IPTOS_DSCP_CS4 },
|
|
{ "cs5", IPTOS_DSCP_CS5 },
|
|
{ "cs6", IPTOS_DSCP_CS6 },
|
|
{ "cs7", IPTOS_DSCP_CS7 },
|
|
{ "ef", IPTOS_DSCP_EF },
|
|
{ "inetcontrol", IPTOS_PREC_INTERNETCONTROL },
|
|
{ "lowdelay", IPTOS_LOWDELAY },
|
|
{ "netcontrol", IPTOS_PREC_NETCONTROL },
|
|
{ "reliability", IPTOS_RELIABILITY },
|
|
{ "throughput", IPTOS_THROUGHPUT },
|
|
{ NULL, -1 },
|
|
};
|
|
|
|
for (t = toskeywords; t->keyword != NULL; t++) {
|
|
if (strcmp(s, t->keyword) == 0) {
|
|
*val = t->val;
|
|
return (1);
|
|
}
|
|
}
|
|
|
|
return (0);
|
|
}
|
|
|
|
void
|
|
report_connect(const struct sockaddr *sa, socklen_t salen)
|
|
{
|
|
char remote_host[NI_MAXHOST];
|
|
char remote_port[NI_MAXSERV];
|
|
int herr;
|
|
int flags = NI_NUMERICSERV;
|
|
|
|
if (nflag)
|
|
flags |= NI_NUMERICHOST;
|
|
|
|
if ((herr = getnameinfo(sa, salen,
|
|
remote_host, sizeof(remote_host),
|
|
remote_port, sizeof(remote_port),
|
|
flags)) != 0) {
|
|
if (herr == EAI_SYSTEM)
|
|
err(1, "getnameinfo");
|
|
else
|
|
errx(1, "getnameinfo: %s", gai_strerror(herr));
|
|
}
|
|
|
|
fprintf(stderr,
|
|
"Connection from %s %s "
|
|
"received!\n", remote_host, remote_port);
|
|
}
|
|
|
|
void
|
|
help(void)
|
|
{
|
|
usage(0);
|
|
fprintf(stderr, "\tCommand Summary:\n\
|
|
\t-4 Use IPv4\n\
|
|
\t-6 Use IPv6\n\
|
|
\t-D Enable the debug socket option\n\
|
|
\t-d Detach from stdin\n\
|
|
\t-F Pass socket fd\n\
|
|
\t-h This help text\n\
|
|
\t-I length TCP receive buffer length\n\
|
|
\t-i secs\t Delay interval for lines sent, ports scanned\n\
|
|
\t-k Keep inbound sockets open for multiple connects\n\
|
|
\t-l Listen mode, for inbound connects\n\
|
|
\t-N Shutdown the network socket after EOF on stdin\n\
|
|
\t-n Suppress name/port resolutions\n\
|
|
\t-O length TCP send buffer length\n\
|
|
\t-P proxyuser\tUsername for proxy authentication\n\
|
|
\t-p port\t Specify local port for remote connects\n\
|
|
\t-r Randomize remote ports\n\
|
|
\t-S Enable the TCP MD5 signature option\n\
|
|
\t-s addr\t Local source address\n\
|
|
\t-T toskeyword\tSet IP Type of Service\n\
|
|
\t-t Answer TELNET negotiation\n\
|
|
\t-U Use UNIX domain socket\n\
|
|
\t-u UDP mode\n\
|
|
\t-V rtable Specify alternate routing table\n\
|
|
\t-v Verbose\n\
|
|
\t-w secs\t Timeout for connects and final net reads\n\
|
|
\t-X proto Proxy protocol: \"4\", \"5\" (SOCKS) or \"connect\"\n\
|
|
\t-x addr[:port]\tSpecify proxy address and port\n\
|
|
\t-z Zero-I/O mode [used for scanning]\n\
|
|
Port numbers can be individual or ranges: lo-hi [inclusive]\n");
|
|
exit(1);
|
|
}
|
|
|
|
void
|
|
usage(int ret)
|
|
{
|
|
fprintf(stderr,
|
|
"usage: nc [-46DdFhklNnrStUuvz] [-I length] [-i interval] [-O length]\n"
|
|
"\t [-P proxy_username] [-p source_port] [-s source] [-T ToS]\n"
|
|
"\t [-V rtable] [-w timeout] [-X proxy_protocol]\n"
|
|
"\t [-x proxy_address[:port]] [destination] [port]\n");
|
|
if (ret)
|
|
exit(1);
|
|
}
|
|
|
|
/* *** src/usr.bin/nc/socks.c *** */
|
|
|
|
|
|
/* $OpenBSD: socks.c,v 1.20 2012/03/08 09:56:28 espie Exp $ */
|
|
|
|
/*
|
|
* Copyright (c) 1999 Niklas Hallqvist. All rights reserved.
|
|
* Copyright (c) 2004, 2005 Damien Miller. All rights reserved.
|
|
*
|
|
* Redistribution and use in source and binary forms, with or without
|
|
* modification, are permitted provided that the following conditions
|
|
* are met:
|
|
* 1. Redistributions of source code must retain the above copyright
|
|
* notice, this list of conditions and the following disclaimer.
|
|
* 2. Redistributions in binary form must reproduce the above copyright
|
|
* notice, this list of conditions and the following disclaimer in the
|
|
* documentation and/or other materials provided with the distribution.
|
|
*
|
|
* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
|
|
* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
|
|
* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
|
|
* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
|
|
* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
|
|
* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
|
|
* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
|
|
* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
|
|
* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
|
|
* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
|
|
*/
|
|
|
|
#include <sys/types.h>
|
|
#include <sys/socket.h>
|
|
#include <netinet/in.h>
|
|
#include <arpa/inet.h>
|
|
|
|
#include <errno.h>
|
|
#include <netdb.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <unistd.h>
|
|
#include <resolv.h>
|
|
|
|
#define SOCKS_PORT "1080"
|
|
#define HTTP_PROXY_PORT "3128"
|
|
#define HTTP_MAXHDRS 64
|
|
#define SOCKS_V5 5
|
|
#define SOCKS_V4 4
|
|
#define SOCKS_NOAUTH 0
|
|
#define SOCKS_NOMETHOD 0xff
|
|
#define SOCKS_CONNECT 1
|
|
#define SOCKS_IPV4 1
|
|
#define SOCKS_DOMAIN 3
|
|
#define SOCKS_IPV6 4
|
|
|
|
int remote_connect(const char *, const char *, struct addrinfo);
|
|
int socks_connect(const char *, const char *, struct addrinfo,
|
|
const char *, const char *, struct addrinfo, int,
|
|
const char *);
|
|
|
|
static int
|
|
decode_addrport(const char *h, const char *p, struct sockaddr *addr,
|
|
socklen_t addrlen, int v4only, int numeric)
|
|
{
|
|
int r;
|
|
struct addrinfo hints, *res;
|
|
|
|
bzero(&hints, sizeof(hints));
|
|
hints.ai_family = v4only ? PF_INET : PF_UNSPEC;
|
|
hints.ai_flags = numeric ? AI_NUMERICHOST : 0;
|
|
hints.ai_socktype = SOCK_STREAM;
|
|
r = getaddrinfo(h, p, &hints, &res);
|
|
/* Don't fatal when attempting to convert a numeric address */
|
|
if (r != 0) {
|
|
if (!numeric) {
|
|
errx(1, "getaddrinfo(\"%.64s\", \"%.64s\"): %s", h, p,
|
|
gai_strerror(r));
|
|
}
|
|
return (-1);
|
|
}
|
|
if (addrlen < res->ai_addrlen) {
|
|
freeaddrinfo(res);
|
|
errx(1, "internal error: addrlen < res->ai_addrlen");
|
|
}
|
|
memcpy(addr, res->ai_addr, res->ai_addrlen);
|
|
freeaddrinfo(res);
|
|
return (0);
|
|
}
|
|
|
|
static int
|
|
proxy_read_line(int fd, char *buf, size_t bufsz)
|
|
{
|
|
size_t off;
|
|
|
|
for(off = 0;;) {
|
|
if (off >= bufsz)
|
|
errx(1, "proxy read too long");
|
|
if (atomicio(read, fd, buf + off, 1) != 1)
|
|
err(1, "proxy read");
|
|
/* Skip CR */
|
|
if (buf[off] == '\r')
|
|
continue;
|
|
if (buf[off] == '\n') {
|
|
buf[off] = '\0';
|
|
break;
|
|
}
|
|
off++;
|
|
}
|
|
return (off);
|
|
}
|
|
|
|
static const char *
|
|
getproxypass(const char *proxyuser, const char *proxyhost)
|
|
{
|
|
char prompt[512];
|
|
static char pw[256];
|
|
|
|
snprintf(prompt, sizeof(prompt), "Proxy password for %s@%s: ",
|
|
proxyuser, proxyhost);
|
|
if (readpassphrase(prompt, pw, sizeof(pw), RPP_REQUIRE_TTY) == NULL)
|
|
errx(1, "Unable to read proxy passphrase");
|
|
return (pw);
|
|
}
|
|
|
|
int
|
|
socks_connect(const char *host, const char *port,
|
|
struct addrinfo hints __attribute__ ((__unused__)),
|
|
const char *proxyhost, const char *proxyport, struct addrinfo proxyhints,
|
|
int socksv, const char *proxyuser)
|
|
{
|
|
int proxyfd, r, authretry = 0;
|
|
size_t hlen, wlen = 0;
|
|
unsigned char buf[1024];
|
|
size_t cnt;
|
|
struct sockaddr_storage addr;
|
|
struct sockaddr_in *in4 = (struct sockaddr_in *)&addr;
|
|
struct sockaddr_in6 *in6 = (struct sockaddr_in6 *)&addr;
|
|
in_port_t serverport;
|
|
const char *proxypass = NULL;
|
|
|
|
if (proxyport == NULL)
|
|
proxyport = (socksv == -1) ? HTTP_PROXY_PORT : SOCKS_PORT;
|
|
|
|
/* Abuse API to lookup port */
|
|
if (decode_addrport("0.0.0.0", port, (struct sockaddr *)&addr,
|
|
sizeof(addr), 1, 1) == -1)
|
|
errx(1, "unknown port \"%.64s\"", port);
|
|
serverport = in4->sin_port;
|
|
|
|
again:
|
|
if (authretry++ > 3)
|
|
errx(1, "Too many authentication failures");
|
|
|
|
proxyfd = remote_connect(proxyhost, proxyport, proxyhints);
|
|
|
|
if (proxyfd < 0)
|
|
return (-1);
|
|
|
|
if (socksv == 5) {
|
|
if (decode_addrport(host, port, (struct sockaddr *)&addr,
|
|
sizeof(addr), 0, 1) == -1)
|
|
addr.ss_family = 0; /* used in switch below */
|
|
|
|
/* Version 5, one method: no authentication */
|
|
buf[0] = SOCKS_V5;
|
|
buf[1] = 1;
|
|
buf[2] = SOCKS_NOAUTH;
|
|
cnt = atomicio(vwrite, proxyfd, buf, 3);
|
|
if (cnt != 3)
|
|
err(1, "write failed (%zu/3)", cnt);
|
|
|
|
cnt = atomicio(read, proxyfd, buf, 2);
|
|
if (cnt != 2)
|
|
err(1, "read failed (%zu/3)", cnt);
|
|
|
|
if (buf[1] == SOCKS_NOMETHOD)
|
|
errx(1, "authentication method negotiation failed");
|
|
|
|
switch (addr.ss_family) {
|
|
case 0:
|
|
/* Version 5, connect: domain name */
|
|
|
|
/* Max domain name length is 255 bytes */
|
|
hlen = strlen(host);
|
|
if (hlen > 255)
|
|
errx(1, "host name too long for SOCKS5");
|
|
buf[0] = SOCKS_V5;
|
|
buf[1] = SOCKS_CONNECT;
|
|
buf[2] = 0;
|
|
buf[3] = SOCKS_DOMAIN;
|
|
buf[4] = hlen;
|
|
memcpy(buf + 5, host, hlen);
|
|
memcpy(buf + 5 + hlen, &serverport, sizeof serverport);
|
|
wlen = 7 + hlen;
|
|
break;
|
|
case AF_INET:
|
|
/* Version 5, connect: IPv4 address */
|
|
buf[0] = SOCKS_V5;
|
|
buf[1] = SOCKS_CONNECT;
|
|
buf[2] = 0;
|
|
buf[3] = SOCKS_IPV4;
|
|
memcpy(buf + 4, &in4->sin_addr, sizeof in4->sin_addr);
|
|
memcpy(buf + 8, &in4->sin_port, sizeof in4->sin_port);
|
|
wlen = 10;
|
|
break;
|
|
case AF_INET6:
|
|
/* Version 5, connect: IPv6 address */
|
|
buf[0] = SOCKS_V5;
|
|
buf[1] = SOCKS_CONNECT;
|
|
buf[2] = 0;
|
|
buf[3] = SOCKS_IPV6;
|
|
memcpy(buf + 4, &in6->sin6_addr, sizeof in6->sin6_addr);
|
|
memcpy(buf + 20, &in6->sin6_port,
|
|
sizeof in6->sin6_port);
|
|
wlen = 22;
|
|
break;
|
|
default:
|
|
errx(1, "internal error: silly AF");
|
|
}
|
|
|
|
cnt = atomicio(vwrite, proxyfd, buf, wlen);
|
|
if (cnt != wlen)
|
|
err(1, "write failed (%zu/%zu)", cnt, wlen);
|
|
|
|
cnt = atomicio(read, proxyfd, buf, 4);
|
|
if (cnt != 4)
|
|
err(1, "read failed (%zu/4)", cnt);
|
|
if (buf[1] != 0)
|
|
errx(1, "connection failed, SOCKS error %d", buf[1]);
|
|
switch (buf[3]) {
|
|
case SOCKS_IPV4:
|
|
cnt = atomicio(read, proxyfd, buf + 4, 6);
|
|
if (cnt != 6)
|
|
err(1, "read failed (%zu/6)", cnt);
|
|
break;
|
|
case SOCKS_IPV6:
|
|
cnt = atomicio(read, proxyfd, buf + 4, 18);
|
|
if (cnt != 18)
|
|
err(1, "read failed (%zu/18)", cnt);
|
|
break;
|
|
default:
|
|
errx(1, "connection failed, unsupported address type");
|
|
}
|
|
} else if (socksv == 4) {
|
|
/* This will exit on lookup failure */
|
|
decode_addrport(host, port, (struct sockaddr *)&addr,
|
|
sizeof(addr), 1, 0);
|
|
|
|
/* Version 4 */
|
|
buf[0] = SOCKS_V4;
|
|
buf[1] = SOCKS_CONNECT; /* connect */
|
|
memcpy(buf + 2, &in4->sin_port, sizeof in4->sin_port);
|
|
memcpy(buf + 4, &in4->sin_addr, sizeof in4->sin_addr);
|
|
buf[8] = 0; /* empty username */
|
|
wlen = 9;
|
|
|
|
cnt = atomicio(vwrite, proxyfd, buf, wlen);
|
|
if (cnt != wlen)
|
|
err(1, "write failed (%zu/%zu)", cnt, wlen);
|
|
|
|
cnt = atomicio(read, proxyfd, buf, 8);
|
|
if (cnt != 8)
|
|
err(1, "read failed (%zu/8)", cnt);
|
|
if (buf[1] != 90)
|
|
errx(1, "connection failed, SOCKS error %d", buf[1]);
|
|
} else if (socksv == -1) {
|
|
/* HTTP proxy CONNECT */
|
|
|
|
/* Disallow bad chars in hostname */
|
|
if (strcspn(host, "\r\n\t []:") != strlen(host))
|
|
errx(1, "Invalid hostname");
|
|
|
|
/* Try to be sane about numeric IPv6 addresses */
|
|
if (strchr(host, ':') != NULL) {
|
|
r = snprintf(buf, sizeof(buf),
|
|
"CONNECT [%s]:%d HTTP/1.0\r\n",
|
|
host, ntohs(serverport));
|
|
} else {
|
|
r = snprintf(buf, sizeof(buf),
|
|
"CONNECT %s:%d HTTP/1.0\r\n",
|
|
host, ntohs(serverport));
|
|
}
|
|
if (r == -1 || (size_t)r >= sizeof(buf))
|
|
errx(1, "hostname too long");
|
|
r = strlen(buf);
|
|
|
|
cnt = atomicio(vwrite, proxyfd, buf, r);
|
|
if (cnt != (size_t)r)
|
|
err(1, "write failed (%zu/%d)", cnt, r);
|
|
|
|
if (authretry > 1) {
|
|
char resp[1024];
|
|
|
|
proxypass = getproxypass(proxyuser, proxyhost);
|
|
r = snprintf(buf, sizeof(buf), "%s:%s",
|
|
proxyuser, proxypass);
|
|
if (r == -1 || (size_t)r >= sizeof(buf) ||
|
|
b64_ntop(buf, strlen(buf), resp,
|
|
sizeof(resp)) == -1)
|
|
errx(1, "Proxy username/password too long");
|
|
r = snprintf(buf, sizeof(buf), "Proxy-Authorization: "
|
|
"Basic %s\r\n", resp);
|
|
if (r == -1 || (size_t)r >= sizeof(buf))
|
|
errx(1, "Proxy auth response too long");
|
|
r = strlen(buf);
|
|
if ((cnt = atomicio(vwrite, proxyfd, buf, r)) != (size_t)r)
|
|
err(1, "write failed (%zu/%d)", cnt, r);
|
|
}
|
|
|
|
/* Terminate headers */
|
|
if ((r = atomicio(vwrite, proxyfd, "\r\n", 2)) != 2)
|
|
err(1, "write failed (2/%d)", r);
|
|
|
|
/* Read status reply */
|
|
proxy_read_line(proxyfd, buf, sizeof(buf));
|
|
if (proxyuser != NULL &&
|
|
strncmp(buf, "HTTP/1.0 407 ", 12) == 0) {
|
|
if (authretry > 1) {
|
|
fprintf(stderr, "Proxy authentication "
|
|
"failed\n");
|
|
}
|
|
close(proxyfd);
|
|
goto again;
|
|
} else if (strncmp(buf, "HTTP/1.0 200 ", 12) != 0 &&
|
|
strncmp(buf, "HTTP/1.1 200 ", 12) != 0)
|
|
errx(1, "Proxy error: \"%s\"", buf);
|
|
|
|
/* Headers continue until we hit an empty line */
|
|
for (r = 0; r < HTTP_MAXHDRS; r++) {
|
|
proxy_read_line(proxyfd, buf, sizeof(buf));
|
|
if (*buf == '\0')
|
|
break;
|
|
}
|
|
if (*buf != '\0')
|
|
errx(1, "Too many proxy headers received");
|
|
} else
|
|
errx(1, "Unknown proxy protocol %d", socksv);
|
|
|
|
return (proxyfd);
|
|
}
|
|
|