diff options
Diffstat (limited to 'contrib/netcat/socks.c')
| -rw-r--r-- | contrib/netcat/socks.c | 235 |
1 files changed, 235 insertions, 0 deletions
diff --git a/contrib/netcat/socks.c b/contrib/netcat/socks.c new file mode 100644 index 0000000..e7d35b6 --- /dev/null +++ b/contrib/netcat/socks.c @@ -0,0 +1,235 @@ +/* $OpenBSD: socks.c,v 1.9 2004/10/17 03:13:55 djm Exp $ */ + +/* + * Copyright (c) 1999 Niklas Hallqvist. 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 <err.h> +#include <errno.h> +#include <netdb.h> +#include <stdio.h> +#include <stdlib.h> +#include <string.h> +#include <unistd.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 + + +int remote_connect(char *, char *, struct addrinfo); +int socks_connect(char *host, char *port, struct addrinfo hints, + char *proxyhost, char *proxyport, struct addrinfo proxyhints, + int socksv); + +static in_addr_t +decode_addr(const char *s) +{ + struct hostent *hp = gethostbyname (s); + struct in_addr retval; + + if (hp) + return *(in_addr_t *)hp->h_addr_list[0]; + if (inet_aton (s, &retval)) + return retval.s_addr; + errx (1, "cannot decode address \"%s\"", s); +} + +static in_port_t +decode_port(const char *s) +{ + struct servent *sp; + in_port_t port; + char *p; + + port = strtol (s, &p, 10); + if (s == p) { + sp = getservbyname (s, "tcp"); + if (sp) + return sp->s_port; + } + if (*s != '\0' && *p == '\0') + return htons (port); + errx (1, "cannot decode port \"%s\"", s); +} + +static int +proxy_read_line(int fd, char *buf, int bufsz) +{ + int r, off; + + for(off = 0;;) { + if (off >= bufsz) + errx(1, "proxy read too long"); + if ((r = read(fd, buf + off, 1)) <= 0) { + if (r == -1 && errno == EINTR) + continue; + err(1, "proxy read"); + } + /* Skip CR */ + if (buf[off] == '\r') + continue; + if (buf[off] == '\n') { + buf[off] = '\0'; + break; + } + off++; + } + return (off); +} + +int +socks_connect(char *host, char *port, struct addrinfo hints, + char *proxyhost, char *proxyport, struct addrinfo proxyhints, + int socksv) +{ + int proxyfd, r; + unsigned char buf[1024]; + ssize_t cnt; + in_addr_t serveraddr; + in_port_t serverport; + + if (proxyport == NULL) + proxyport = (socksv == -1) ? HTTP_PROXY_PORT : SOCKS_PORT; + + proxyfd = remote_connect(proxyhost, proxyport, proxyhints); + + if (proxyfd < 0) + return -1; + + serveraddr = decode_addr (host); + serverport = decode_port (port); + + if (socksv == 5) { + /* Version 5, one method: no authentication */ + buf[0] = SOCKS_V5; + buf[1] = 1; + buf[2] = SOCKS_NOAUTH; + cnt = write (proxyfd, buf, 3); + if (cnt == -1) + err (1, "write failed"); + if (cnt != 3) + errx (1, "short write, %d (expected 3)", cnt); + + read (proxyfd, buf, 2); + if (buf[1] == SOCKS_NOMETHOD) + errx (1, "authentication method negotiation failed"); + + /* Version 5, connect: IPv4 address */ + buf[0] = SOCKS_V5; + buf[1] = SOCKS_CONNECT; + buf[2] = 0; + buf[3] = SOCKS_IPV4; + memcpy (buf + 4, &serveraddr, sizeof serveraddr); + memcpy (buf + 8, &serverport, sizeof serverport); + + /* XXX Handle short writes better */ + cnt = write (proxyfd, buf, 10); + if (cnt == -1) + err (1, "write failed"); + if (cnt != 10) + errx (1, "short write, %d (expected 10)", cnt); + + /* XXX Handle short reads better */ + cnt = read (proxyfd, buf, sizeof buf); + if (cnt == -1) + err (1, "read failed"); + if (cnt != 10) + errx (1, "unexpected reply size %d (expected 10)", cnt); + if (buf[1] != 0) + errx (1, "connection failed, SOCKS error %d", buf[1]); + } else if (socksv == 4) { + /* Version 4 */ + buf[0] = SOCKS_V4; + buf[1] = SOCKS_CONNECT; /* connect */ + memcpy (buf + 2, &serverport, sizeof serverport); + memcpy (buf + 4, &serveraddr, sizeof serveraddr); + buf[8] = 0; /* empty username */ + + cnt = write (proxyfd, buf, 9); + if (cnt == -1) + err (1, "write failed"); + if (cnt != 9) + errx (1, "short write, %d (expected 9)", cnt); + + /* XXX Handle short reads better */ + cnt = read (proxyfd, buf, 8); + if (cnt == -1) + err (1, "read failed"); + if (cnt != 8) + errx (1, "unexpected reply size %d (expected 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\r\n", + host, ntohs(serverport)); + } else { + r = snprintf(buf, sizeof(buf), + "CONNECT %s:%d HTTP/1.0\r\n\r\n", + host, ntohs(serverport)); + } + if (r == -1 || r >= sizeof(buf)) + errx (1, "hostname too long"); + r = strlen(buf); + + /* XXX atomicio */ + cnt = write (proxyfd, buf, r); + if (cnt == -1) + err (1, "write failed"); + if (cnt != r) + errx (1, "short write, %d (expected %d)", cnt, r); + + /* Read reply */ + for (r = 0; r < HTTP_MAXHDRS; r++) { + proxy_read_line(proxyfd, buf, sizeof(buf)); + if (r == 0 && strncmp(buf, "HTTP/1.0 200 ", 12) != 0) + errx (1, "Proxy error: \"%s\"", buf); + /* Discard headers until we hit an empty line */ + if (*buf == '\0') + break; + } + } else + errx (1, "Unknown proxy protocol %d", socksv); + + return proxyfd; +} |
