in regress/netcat.c [1450:1663]
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);
}