1 | /***************************************************************************
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2 | * _ _ ____ _
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3 | * Project ___| | | | _ \| |
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4 | * / __| | | | |_) | |
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5 | * | (__| |_| | _ <| |___
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6 | * \___|\___/|_| \_\_____|
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7 | *
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8 | * Copyright (C) 1998 - 2017, Daniel Stenberg, <daniel@haxx.se>, et al.
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9 | *
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10 | * This software is licensed as described in the file COPYING, which
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11 | * you should have received as part of this distribution. The terms
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12 | * are also available at https://curl.haxx.se/docs/copyright.html.
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13 | *
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14 | * You may opt to use, copy, modify, merge, publish, distribute and/or sell
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15 | * copies of the Software, and permit persons to whom the Software is
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16 | * furnished to do so, under the terms of the COPYING file.
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17 | *
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18 | * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
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19 | * KIND, either express or implied.
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20 | *
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21 | ***************************************************************************/
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22 |
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23 | #include "curl_setup.h"
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24 |
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25 | #if !defined(CURL_DISABLE_PROXY)
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26 |
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27 | #ifdef HAVE_NETINET_IN_H
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28 | #include <netinet/in.h>
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29 | #endif
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30 | #ifdef HAVE_ARPA_INET_H
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31 | #include <arpa/inet.h>
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32 | #endif
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33 |
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34 | #include "urldata.h"
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35 | #include "sendf.h"
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36 | #include "select.h"
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37 | #include "connect.h"
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38 | #include "timeval.h"
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39 | #include "socks.h"
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40 |
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41 | /* The last #include file should be: */
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42 | #include "memdebug.h"
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43 |
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44 | /*
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45 | * Helper read-from-socket functions. Does the same as Curl_read() but it
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46 | * blocks until all bytes amount of buffersize will be read. No more, no less.
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47 | *
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48 | * This is STUPID BLOCKING behaviour which we frown upon, but right now this
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49 | * is what we have...
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50 | */
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51 | int Curl_blockread_all(struct connectdata *conn, /* connection data */
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52 | curl_socket_t sockfd, /* read from this socket */
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53 | char *buf, /* store read data here */
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54 | ssize_t buffersize, /* max amount to read */
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55 | ssize_t *n) /* amount bytes read */
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56 | {
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57 | ssize_t nread;
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58 | ssize_t allread = 0;
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59 | int result;
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60 | timediff_t timeleft;
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61 | *n = 0;
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62 | for(;;) {
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63 | timeleft = Curl_timeleft(conn->data, NULL, TRUE);
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64 | if(timeleft < 0) {
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65 | /* we already got the timeout */
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66 | result = CURLE_OPERATION_TIMEDOUT;
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67 | break;
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68 | }
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69 | if(SOCKET_READABLE(sockfd, timeleft) <= 0) {
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70 | result = ~CURLE_OK;
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71 | break;
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72 | }
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73 | result = Curl_read_plain(sockfd, buf, buffersize, &nread);
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74 | if(CURLE_AGAIN == result)
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75 | continue;
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76 | if(result)
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77 | break;
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78 |
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79 | if(buffersize == nread) {
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80 | allread += nread;
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81 | *n = allread;
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82 | result = CURLE_OK;
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83 | break;
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84 | }
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85 | if(!nread) {
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86 | result = ~CURLE_OK;
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87 | break;
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88 | }
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89 |
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90 | buffersize -= nread;
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91 | buf += nread;
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92 | allread += nread;
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93 | }
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94 | return result;
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95 | }
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96 |
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97 | /*
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98 | * This function logs in to a SOCKS4 proxy and sends the specifics to the final
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99 | * destination server.
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100 | *
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101 | * Reference :
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102 | * http://socks.permeo.com/protocol/socks4.protocol
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103 | *
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104 | * Note :
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105 | * Set protocol4a=true for "SOCKS 4A (Simple Extension to SOCKS 4 Protocol)"
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106 | * Nonsupport "Identification Protocol (RFC1413)"
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107 | */
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108 | CURLcode Curl_SOCKS4(const char *proxy_user,
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109 | const char *hostname,
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110 | int remote_port,
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111 | int sockindex,
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112 | struct connectdata *conn)
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113 | {
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114 | const bool protocol4a =
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115 | (conn->socks_proxy.proxytype == CURLPROXY_SOCKS4A) ? TRUE : FALSE;
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116 | #define SOCKS4REQLEN 262
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117 | unsigned char socksreq[SOCKS4REQLEN]; /* room for SOCKS4 request incl. user
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118 | id */
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119 | int result;
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120 | CURLcode code;
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121 | curl_socket_t sock = conn->sock[sockindex];
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122 | struct Curl_easy *data = conn->data;
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123 |
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124 | if(Curl_timeleft(data, NULL, TRUE) < 0) {
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125 | /* time-out, bail out, go home */
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126 | failf(data, "Connection time-out");
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127 | return CURLE_OPERATION_TIMEDOUT;
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128 | }
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129 |
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130 | if(conn->bits.httpproxy)
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131 | infof(conn->data, "SOCKS4%s: connecting to HTTP proxy %s port %d\n",
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132 | protocol4a ? "a" : "", hostname, remote_port);
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133 |
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134 | (void)curlx_nonblock(sock, FALSE);
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135 |
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136 | infof(data, "SOCKS4 communication to %s:%d\n", hostname, remote_port);
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137 |
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138 | /*
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139 | * Compose socks4 request
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140 | *
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141 | * Request format
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142 | *
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143 | * +----+----+----+----+----+----+----+----+----+----+....+----+
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144 | * | VN | CD | DSTPORT | DSTIP | USERID |NULL|
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145 | * +----+----+----+----+----+----+----+----+----+----+....+----+
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146 | * # of bytes: 1 1 2 4 variable 1
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147 | */
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148 |
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149 | socksreq[0] = 4; /* version (SOCKS4) */
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150 | socksreq[1] = 1; /* connect */
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151 | socksreq[2] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */
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152 | socksreq[3] = (unsigned char)(remote_port & 0xff); /* PORT LSB */
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153 |
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154 | /* DNS resolve only for SOCKS4, not SOCKS4a */
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155 | if(!protocol4a) {
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156 | struct Curl_dns_entry *dns;
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157 | Curl_addrinfo *hp = NULL;
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158 | int rc;
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159 |
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160 | rc = Curl_resolv(conn, hostname, remote_port, &dns);
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161 |
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162 | if(rc == CURLRESOLV_ERROR)
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163 | return CURLE_COULDNT_RESOLVE_PROXY;
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164 |
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165 | if(rc == CURLRESOLV_PENDING)
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166 | /* ignores the return code, but 'dns' remains NULL on failure */
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167 | (void)Curl_resolver_wait_resolv(conn, &dns);
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168 |
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169 | /*
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170 | * We cannot use 'hostent' as a struct that Curl_resolv() returns. It
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171 | * returns a Curl_addrinfo pointer that may not always look the same.
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172 | */
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173 | if(dns)
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174 | hp = dns->addr;
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175 | if(hp) {
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176 | char buf[64];
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177 | Curl_printable_address(hp, buf, sizeof(buf));
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178 |
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179 | if(hp->ai_family == AF_INET) {
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180 | struct sockaddr_in *saddr_in;
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181 |
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182 | saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
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183 | socksreq[4] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[0];
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184 | socksreq[5] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[1];
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185 | socksreq[6] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[2];
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186 | socksreq[7] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[3];
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187 |
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188 | infof(data, "SOCKS4 connect to IPv4 %s (locally resolved)\n", buf);
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189 | }
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190 | else {
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191 | hp = NULL; /* fail! */
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192 |
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193 | failf(data, "SOCKS4 connection to %s not supported\n", buf);
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194 | }
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195 |
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196 | Curl_resolv_unlock(data, dns); /* not used anymore from now on */
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197 | }
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198 | if(!hp) {
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199 | failf(data, "Failed to resolve \"%s\" for SOCKS4 connect.",
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200 | hostname);
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201 | return CURLE_COULDNT_RESOLVE_HOST;
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202 | }
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203 | }
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204 |
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205 | /*
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206 | * This is currently not supporting "Identification Protocol (RFC1413)".
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207 | */
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208 | socksreq[8] = 0; /* ensure empty userid is NUL-terminated */
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209 | if(proxy_user) {
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210 | size_t plen = strlen(proxy_user);
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211 | if(plen >= sizeof(socksreq) - 8) {
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212 | failf(data, "Too long SOCKS proxy name, can't use!\n");
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213 | return CURLE_COULDNT_CONNECT;
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214 | }
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215 | /* copy the proxy name WITH trailing zero */
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216 | memcpy(socksreq + 8, proxy_user, plen + 1);
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217 | }
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218 |
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219 | /*
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220 | * Make connection
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221 | */
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222 | {
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223 | ssize_t actualread;
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224 | ssize_t written;
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225 | ssize_t hostnamelen = 0;
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226 | int packetsize = 9 +
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227 | (int)strlen((char *)socksreq + 8); /* size including NUL */
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228 |
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229 | /* If SOCKS4a, set special invalid IP address 0.0.0.x */
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230 | if(protocol4a) {
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231 | socksreq[4] = 0;
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232 | socksreq[5] = 0;
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233 | socksreq[6] = 0;
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234 | socksreq[7] = 1;
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235 | /* If still enough room in buffer, also append hostname */
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236 | hostnamelen = (ssize_t)strlen(hostname) + 1; /* length including NUL */
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237 | if(packetsize + hostnamelen <= SOCKS4REQLEN)
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238 | strcpy((char *)socksreq + packetsize, hostname);
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239 | else
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240 | hostnamelen = 0; /* Flag: hostname did not fit in buffer */
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241 | }
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242 |
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243 | /* Send request */
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244 | code = Curl_write_plain(conn, sock, (char *)socksreq,
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245 | packetsize + hostnamelen,
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246 | &written);
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247 | if(code || (written != packetsize + hostnamelen)) {
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248 | failf(data, "Failed to send SOCKS4 connect request.");
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249 | return CURLE_COULDNT_CONNECT;
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250 | }
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251 | if(protocol4a && hostnamelen == 0) {
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252 | /* SOCKS4a with very long hostname - send that name separately */
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253 | hostnamelen = (ssize_t)strlen(hostname) + 1;
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254 | code = Curl_write_plain(conn, sock, (char *)hostname, hostnamelen,
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255 | &written);
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256 | if(code || (written != hostnamelen)) {
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257 | failf(data, "Failed to send SOCKS4 connect request.");
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258 | return CURLE_COULDNT_CONNECT;
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259 | }
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260 | }
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261 |
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262 | packetsize = 8; /* receive data size */
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263 |
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264 | /* Receive response */
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265 | result = Curl_blockread_all(conn, sock, (char *)socksreq, packetsize,
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266 | &actualread);
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267 | if(result || (actualread != packetsize)) {
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268 | failf(data, "Failed to receive SOCKS4 connect request ack.");
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269 | return CURLE_COULDNT_CONNECT;
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270 | }
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271 |
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272 | /*
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273 | * Response format
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274 | *
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275 | * +----+----+----+----+----+----+----+----+
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276 | * | VN | CD | DSTPORT | DSTIP |
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277 | * +----+----+----+----+----+----+----+----+
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278 | * # of bytes: 1 1 2 4
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279 | *
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280 | * VN is the version of the reply code and should be 0. CD is the result
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281 | * code with one of the following values:
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282 | *
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283 | * 90: request granted
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284 | * 91: request rejected or failed
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285 | * 92: request rejected because SOCKS server cannot connect to
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286 | * identd on the client
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287 | * 93: request rejected because the client program and identd
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288 | * report different user-ids
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289 | */
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290 |
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291 | /* wrong version ? */
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292 | if(socksreq[0] != 0) {
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293 | failf(data,
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294 | "SOCKS4 reply has wrong version, version should be 4.");
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295 | return CURLE_COULDNT_CONNECT;
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296 | }
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297 |
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298 | /* Result */
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299 | switch(socksreq[1]) {
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300 | case 90:
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301 | infof(data, "SOCKS4%s request granted.\n", protocol4a?"a":"");
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302 | break;
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303 | case 91:
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304 | failf(data,
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305 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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306 | ", request rejected or failed.",
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307 | (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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308 | (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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309 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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310 | (unsigned char)socksreq[1]);
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311 | return CURLE_COULDNT_CONNECT;
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312 | case 92:
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313 | failf(data,
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314 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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315 | ", request rejected because SOCKS server cannot connect to "
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316 | "identd on the client.",
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317 | (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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318 | (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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319 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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320 | (unsigned char)socksreq[1]);
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321 | return CURLE_COULDNT_CONNECT;
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322 | case 93:
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323 | failf(data,
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324 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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325 | ", request rejected because the client program and identd "
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326 | "report different user-ids.",
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327 | (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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328 | (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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329 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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330 | (unsigned char)socksreq[1]);
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331 | return CURLE_COULDNT_CONNECT;
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332 | default:
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333 | failf(data,
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334 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
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335 | ", Unknown.",
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336 | (unsigned char)socksreq[4], (unsigned char)socksreq[5],
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337 | (unsigned char)socksreq[6], (unsigned char)socksreq[7],
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338 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
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339 | (unsigned char)socksreq[1]);
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340 | return CURLE_COULDNT_CONNECT;
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341 | }
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342 | }
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343 |
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344 | (void)curlx_nonblock(sock, TRUE);
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345 |
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346 | return CURLE_OK; /* Proxy was successful! */
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347 | }
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348 |
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349 | /*
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350 | * This function logs in to a SOCKS5 proxy and sends the specifics to the final
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351 | * destination server.
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352 | */
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353 | CURLcode Curl_SOCKS5(const char *proxy_user,
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354 | const char *proxy_password,
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355 | const char *hostname,
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356 | int remote_port,
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357 | int sockindex,
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358 | struct connectdata *conn)
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359 | {
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360 | /*
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361 | According to the RFC1928, section "6. Replies". This is what a SOCK5
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362 | replies:
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363 |
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364 | +----+-----+-------+------+----------+----------+
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365 | |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
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366 | +----+-----+-------+------+----------+----------+
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367 | | 1 | 1 | X'00' | 1 | Variable | 2 |
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368 | +----+-----+-------+------+----------+----------+
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369 |
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370 | Where:
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371 |
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372 | o VER protocol version: X'05'
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373 | o REP Reply field:
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374 | o X'00' succeeded
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375 | */
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376 |
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377 | unsigned char socksreq[600]; /* room for large user/pw (255 max each) */
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378 | int idx;
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379 | ssize_t actualread;
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380 | ssize_t written;
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381 | int result;
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382 | CURLcode code;
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383 | curl_socket_t sock = conn->sock[sockindex];
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384 | struct Curl_easy *data = conn->data;
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385 | timediff_t timeout;
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386 | bool socks5_resolve_local =
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387 | (conn->socks_proxy.proxytype == CURLPROXY_SOCKS5) ? TRUE : FALSE;
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388 | const size_t hostname_len = strlen(hostname);
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389 | ssize_t len = 0;
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390 | const unsigned long auth = data->set.socks5auth;
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391 | bool allow_gssapi = FALSE;
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392 |
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393 | if(conn->bits.httpproxy)
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394 | infof(conn->data, "SOCKS5: connecting to HTTP proxy %s port %d\n",
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395 | hostname, remote_port);
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396 |
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397 | /* RFC1928 chapter 5 specifies max 255 chars for domain name in packet */
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398 | if(!socks5_resolve_local && hostname_len > 255) {
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399 | infof(conn->data, "SOCKS5: server resolving disabled for hostnames of "
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400 | "length > 255 [actual len=%zu]\n", hostname_len);
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401 | socks5_resolve_local = TRUE;
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402 | }
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403 |
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404 | /* get timeout */
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405 | timeout = Curl_timeleft(data, NULL, TRUE);
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406 |
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407 | if(timeout < 0) {
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408 | /* time-out, bail out, go home */
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409 | failf(data, "Connection time-out");
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410 | return CURLE_OPERATION_TIMEDOUT;
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411 | }
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412 |
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413 | (void)curlx_nonblock(sock, TRUE);
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414 |
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415 | /* wait until socket gets connected */
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416 | result = SOCKET_WRITABLE(sock, timeout);
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417 |
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418 | if(-1 == result) {
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419 | failf(conn->data, "SOCKS5: no connection here");
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420 | return CURLE_COULDNT_CONNECT;
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421 | }
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422 | if(0 == result) {
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423 | failf(conn->data, "SOCKS5: connection timeout");
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424 | return CURLE_OPERATION_TIMEDOUT;
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425 | }
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426 |
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427 | if(result & CURL_CSELECT_ERR) {
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428 | failf(conn->data, "SOCKS5: error occurred during connection");
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429 | return CURLE_COULDNT_CONNECT;
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430 | }
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431 |
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432 | if(auth & ~(CURLAUTH_BASIC | CURLAUTH_GSSAPI))
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433 | infof(conn->data,
|
---|
434 | "warning: unsupported value passed to CURLOPT_SOCKS5_AUTH: %lu\n",
|
---|
435 | auth);
|
---|
436 | if(!(auth & CURLAUTH_BASIC))
|
---|
437 | /* disable username/password auth */
|
---|
438 | proxy_user = NULL;
|
---|
439 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
440 | if(auth & CURLAUTH_GSSAPI)
|
---|
441 | allow_gssapi = TRUE;
|
---|
442 | #endif
|
---|
443 |
|
---|
444 | idx = 0;
|
---|
445 | socksreq[idx++] = 5; /* version */
|
---|
446 | idx++; /* reserve for the number of authentication methods */
|
---|
447 | socksreq[idx++] = 0; /* no authentication */
|
---|
448 | if(allow_gssapi)
|
---|
449 | socksreq[idx++] = 1; /* GSS-API */
|
---|
450 | if(proxy_user)
|
---|
451 | socksreq[idx++] = 2; /* username/password */
|
---|
452 | /* write the number of authentication methods */
|
---|
453 | socksreq[1] = (unsigned char) (idx - 2);
|
---|
454 |
|
---|
455 | (void)curlx_nonblock(sock, FALSE);
|
---|
456 |
|
---|
457 | infof(data, "SOCKS5 communication to %s:%d\n", hostname, remote_port);
|
---|
458 |
|
---|
459 | code = Curl_write_plain(conn, sock, (char *)socksreq, (2 + (int)socksreq[1]),
|
---|
460 | &written);
|
---|
461 | if(code || (written != (2 + (int)socksreq[1]))) {
|
---|
462 | failf(data, "Unable to send initial SOCKS5 request.");
|
---|
463 | return CURLE_COULDNT_CONNECT;
|
---|
464 | }
|
---|
465 |
|
---|
466 | (void)curlx_nonblock(sock, TRUE);
|
---|
467 |
|
---|
468 | result = SOCKET_READABLE(sock, timeout);
|
---|
469 |
|
---|
470 | if(-1 == result) {
|
---|
471 | failf(conn->data, "SOCKS5 nothing to read");
|
---|
472 | return CURLE_COULDNT_CONNECT;
|
---|
473 | }
|
---|
474 | if(0 == result) {
|
---|
475 | failf(conn->data, "SOCKS5 read timeout");
|
---|
476 | return CURLE_OPERATION_TIMEDOUT;
|
---|
477 | }
|
---|
478 |
|
---|
479 | if(result & CURL_CSELECT_ERR) {
|
---|
480 | failf(conn->data, "SOCKS5 read error occurred");
|
---|
481 | return CURLE_RECV_ERROR;
|
---|
482 | }
|
---|
483 |
|
---|
484 | (void)curlx_nonblock(sock, FALSE);
|
---|
485 |
|
---|
486 | result = Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread);
|
---|
487 | if(result || (actualread != 2)) {
|
---|
488 | failf(data, "Unable to receive initial SOCKS5 response.");
|
---|
489 | return CURLE_COULDNT_CONNECT;
|
---|
490 | }
|
---|
491 |
|
---|
492 | if(socksreq[0] != 5) {
|
---|
493 | failf(data, "Received invalid version in initial SOCKS5 response.");
|
---|
494 | return CURLE_COULDNT_CONNECT;
|
---|
495 | }
|
---|
496 | if(socksreq[1] == 0) {
|
---|
497 | /* Nothing to do, no authentication needed */
|
---|
498 | ;
|
---|
499 | }
|
---|
500 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
501 | else if(allow_gssapi && (socksreq[1] == 1)) {
|
---|
502 | code = Curl_SOCKS5_gssapi_negotiate(sockindex, conn);
|
---|
503 | if(code) {
|
---|
504 | failf(data, "Unable to negotiate SOCKS5 GSS-API context.");
|
---|
505 | return CURLE_COULDNT_CONNECT;
|
---|
506 | }
|
---|
507 | }
|
---|
508 | #endif
|
---|
509 | else if(socksreq[1] == 2) {
|
---|
510 | /* Needs user name and password */
|
---|
511 | size_t proxy_user_len, proxy_password_len;
|
---|
512 | if(proxy_user && proxy_password) {
|
---|
513 | proxy_user_len = strlen(proxy_user);
|
---|
514 | proxy_password_len = strlen(proxy_password);
|
---|
515 | }
|
---|
516 | else {
|
---|
517 | proxy_user_len = 0;
|
---|
518 | proxy_password_len = 0;
|
---|
519 | }
|
---|
520 |
|
---|
521 | /* username/password request looks like
|
---|
522 | * +----+------+----------+------+----------+
|
---|
523 | * |VER | ULEN | UNAME | PLEN | PASSWD |
|
---|
524 | * +----+------+----------+------+----------+
|
---|
525 | * | 1 | 1 | 1 to 255 | 1 | 1 to 255 |
|
---|
526 | * +----+------+----------+------+----------+
|
---|
527 | */
|
---|
528 | len = 0;
|
---|
529 | socksreq[len++] = 1; /* username/pw subnegotiation version */
|
---|
530 | socksreq[len++] = (unsigned char) proxy_user_len;
|
---|
531 | if(proxy_user && proxy_user_len)
|
---|
532 | memcpy(socksreq + len, proxy_user, proxy_user_len);
|
---|
533 | len += proxy_user_len;
|
---|
534 | socksreq[len++] = (unsigned char) proxy_password_len;
|
---|
535 | if(proxy_password && proxy_password_len)
|
---|
536 | memcpy(socksreq + len, proxy_password, proxy_password_len);
|
---|
537 | len += proxy_password_len;
|
---|
538 |
|
---|
539 | code = Curl_write_plain(conn, sock, (char *)socksreq, len, &written);
|
---|
540 | if(code || (len != written)) {
|
---|
541 | failf(data, "Failed to send SOCKS5 sub-negotiation request.");
|
---|
542 | return CURLE_COULDNT_CONNECT;
|
---|
543 | }
|
---|
544 |
|
---|
545 | result = Curl_blockread_all(conn, sock, (char *)socksreq, 2, &actualread);
|
---|
546 | if(result || (actualread != 2)) {
|
---|
547 | failf(data, "Unable to receive SOCKS5 sub-negotiation response.");
|
---|
548 | return CURLE_COULDNT_CONNECT;
|
---|
549 | }
|
---|
550 |
|
---|
551 | /* ignore the first (VER) byte */
|
---|
552 | if(socksreq[1] != 0) { /* status */
|
---|
553 | failf(data, "User was rejected by the SOCKS5 server (%d %d).",
|
---|
554 | socksreq[0], socksreq[1]);
|
---|
555 | return CURLE_COULDNT_CONNECT;
|
---|
556 | }
|
---|
557 |
|
---|
558 | /* Everything is good so far, user was authenticated! */
|
---|
559 | }
|
---|
560 | else {
|
---|
561 | /* error */
|
---|
562 | if(!allow_gssapi && (socksreq[1] == 1)) {
|
---|
563 | failf(data,
|
---|
564 | "SOCKS5 GSSAPI per-message authentication is not supported.");
|
---|
565 | return CURLE_COULDNT_CONNECT;
|
---|
566 | }
|
---|
567 | if(socksreq[1] == 255) {
|
---|
568 | if(!proxy_user || !*proxy_user) {
|
---|
569 | failf(data,
|
---|
570 | "No authentication method was acceptable. (It is quite likely"
|
---|
571 | " that the SOCKS5 server wanted a username/password, since none"
|
---|
572 | " was supplied to the server on this connection.)");
|
---|
573 | }
|
---|
574 | else {
|
---|
575 | failf(data, "No authentication method was acceptable.");
|
---|
576 | }
|
---|
577 | return CURLE_COULDNT_CONNECT;
|
---|
578 | }
|
---|
579 | else {
|
---|
580 | failf(data,
|
---|
581 | "Undocumented SOCKS5 mode attempted to be used by server.");
|
---|
582 | return CURLE_COULDNT_CONNECT;
|
---|
583 | }
|
---|
584 | }
|
---|
585 |
|
---|
586 | /* Authentication is complete, now specify destination to the proxy */
|
---|
587 | len = 0;
|
---|
588 | socksreq[len++] = 5; /* version (SOCKS5) */
|
---|
589 | socksreq[len++] = 1; /* connect */
|
---|
590 | socksreq[len++] = 0; /* must be zero */
|
---|
591 |
|
---|
592 | if(!socks5_resolve_local) {
|
---|
593 | socksreq[len++] = 3; /* ATYP: domain name = 3 */
|
---|
594 | socksreq[len++] = (char) hostname_len; /* address length */
|
---|
595 | memcpy(&socksreq[len], hostname, hostname_len); /* address str w/o NULL */
|
---|
596 | len += hostname_len;
|
---|
597 | }
|
---|
598 | else {
|
---|
599 | struct Curl_dns_entry *dns;
|
---|
600 | Curl_addrinfo *hp = NULL;
|
---|
601 | int rc = Curl_resolv(conn, hostname, remote_port, &dns);
|
---|
602 |
|
---|
603 | if(rc == CURLRESOLV_ERROR)
|
---|
604 | return CURLE_COULDNT_RESOLVE_HOST;
|
---|
605 |
|
---|
606 | if(rc == CURLRESOLV_PENDING) {
|
---|
607 | /* this requires that we're in "wait for resolve" state */
|
---|
608 | code = Curl_resolver_wait_resolv(conn, &dns);
|
---|
609 | if(code)
|
---|
610 | return code;
|
---|
611 | }
|
---|
612 |
|
---|
613 | /*
|
---|
614 | * We cannot use 'hostent' as a struct that Curl_resolv() returns. It
|
---|
615 | * returns a Curl_addrinfo pointer that may not always look the same.
|
---|
616 | */
|
---|
617 | if(dns)
|
---|
618 | hp = dns->addr;
|
---|
619 | if(hp) {
|
---|
620 | int i;
|
---|
621 | char buf[64];
|
---|
622 | Curl_printable_address(hp, buf, sizeof(buf));
|
---|
623 |
|
---|
624 | if(hp->ai_family == AF_INET) {
|
---|
625 | struct sockaddr_in *saddr_in;
|
---|
626 | socksreq[len++] = 1; /* ATYP: IPv4 = 1 */
|
---|
627 |
|
---|
628 | saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
|
---|
629 | for(i = 0; i < 4; i++) {
|
---|
630 | socksreq[len++] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[i];
|
---|
631 | }
|
---|
632 |
|
---|
633 | infof(data, "SOCKS5 connect to IPv4 %s (locally resolved)\n", buf);
|
---|
634 | }
|
---|
635 | #ifdef ENABLE_IPV6
|
---|
636 | else if(hp->ai_family == AF_INET6) {
|
---|
637 | struct sockaddr_in6 *saddr_in6;
|
---|
638 | socksreq[len++] = 4; /* ATYP: IPv6 = 4 */
|
---|
639 |
|
---|
640 | saddr_in6 = (struct sockaddr_in6 *)(void *)hp->ai_addr;
|
---|
641 | for(i = 0; i < 16; i++) {
|
---|
642 | socksreq[len++] =
|
---|
643 | ((unsigned char *)&saddr_in6->sin6_addr.s6_addr)[i];
|
---|
644 | }
|
---|
645 |
|
---|
646 | infof(data, "SOCKS5 connect to IPv6 %s (locally resolved)\n", buf);
|
---|
647 | }
|
---|
648 | #endif
|
---|
649 | else {
|
---|
650 | hp = NULL; /* fail! */
|
---|
651 |
|
---|
652 | failf(data, "SOCKS5 connection to %s not supported\n", buf);
|
---|
653 | }
|
---|
654 |
|
---|
655 | Curl_resolv_unlock(data, dns); /* not used anymore from now on */
|
---|
656 | }
|
---|
657 | if(!hp) {
|
---|
658 | failf(data, "Failed to resolve \"%s\" for SOCKS5 connect.",
|
---|
659 | hostname);
|
---|
660 | return CURLE_COULDNT_RESOLVE_HOST;
|
---|
661 | }
|
---|
662 | }
|
---|
663 |
|
---|
664 | socksreq[len++] = (unsigned char)((remote_port >> 8) & 0xff); /* PORT MSB */
|
---|
665 | socksreq[len++] = (unsigned char)(remote_port & 0xff); /* PORT LSB */
|
---|
666 |
|
---|
667 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
668 | if(conn->socks5_gssapi_enctype) {
|
---|
669 | failf(data, "SOCKS5 GSS-API protection not yet implemented.");
|
---|
670 | }
|
---|
671 | else
|
---|
672 | #endif
|
---|
673 | code = Curl_write_plain(conn, sock, (char *)socksreq, len, &written);
|
---|
674 |
|
---|
675 | if(code || (len != written)) {
|
---|
676 | failf(data, "Failed to send SOCKS5 connect request.");
|
---|
677 | return CURLE_COULDNT_CONNECT;
|
---|
678 | }
|
---|
679 |
|
---|
680 | len = 10; /* minimum packet size is 10 */
|
---|
681 |
|
---|
682 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
683 | if(conn->socks5_gssapi_enctype) {
|
---|
684 | failf(data, "SOCKS5 GSS-API protection not yet implemented.");
|
---|
685 | }
|
---|
686 | else
|
---|
687 | #endif
|
---|
688 | result = Curl_blockread_all(conn, sock, (char *)socksreq,
|
---|
689 | len, &actualread);
|
---|
690 |
|
---|
691 | if(result || (len != actualread)) {
|
---|
692 | failf(data, "Failed to receive SOCKS5 connect request ack.");
|
---|
693 | return CURLE_COULDNT_CONNECT;
|
---|
694 | }
|
---|
695 |
|
---|
696 | if(socksreq[0] != 5) { /* version */
|
---|
697 | failf(data,
|
---|
698 | "SOCKS5 reply has wrong version, version should be 5.");
|
---|
699 | return CURLE_COULDNT_CONNECT;
|
---|
700 | }
|
---|
701 |
|
---|
702 | /* Fix: in general, returned BND.ADDR is variable length parameter by RFC
|
---|
703 | 1928, so the reply packet should be read until the end to avoid errors at
|
---|
704 | subsequent protocol level.
|
---|
705 |
|
---|
706 | +----+-----+-------+------+----------+----------+
|
---|
707 | |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
|
---|
708 | +----+-----+-------+------+----------+----------+
|
---|
709 | | 1 | 1 | X'00' | 1 | Variable | 2 |
|
---|
710 | +----+-----+-------+------+----------+----------+
|
---|
711 |
|
---|
712 | ATYP:
|
---|
713 | o IP v4 address: X'01', BND.ADDR = 4 byte
|
---|
714 | o domain name: X'03', BND.ADDR = [ 1 byte length, string ]
|
---|
715 | o IP v6 address: X'04', BND.ADDR = 16 byte
|
---|
716 | */
|
---|
717 |
|
---|
718 | /* Calculate real packet size */
|
---|
719 | if(socksreq[3] == 3) {
|
---|
720 | /* domain name */
|
---|
721 | int addrlen = (int) socksreq[4];
|
---|
722 | len = 5 + addrlen + 2;
|
---|
723 | }
|
---|
724 | else if(socksreq[3] == 4) {
|
---|
725 | /* IPv6 */
|
---|
726 | len = 4 + 16 + 2;
|
---|
727 | }
|
---|
728 |
|
---|
729 | /* At this point we already read first 10 bytes */
|
---|
730 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
731 | if(!conn->socks5_gssapi_enctype) {
|
---|
732 | /* decrypt_gssapi_blockread already read the whole packet */
|
---|
733 | #endif
|
---|
734 | if(len > 10) {
|
---|
735 | result = Curl_blockread_all(conn, sock, (char *)&socksreq[10],
|
---|
736 | len - 10, &actualread);
|
---|
737 | if(result || ((len - 10) != actualread)) {
|
---|
738 | failf(data, "Failed to receive SOCKS5 connect request ack.");
|
---|
739 | return CURLE_COULDNT_CONNECT;
|
---|
740 | }
|
---|
741 | }
|
---|
742 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
743 | }
|
---|
744 | #endif
|
---|
745 |
|
---|
746 | if(socksreq[1] != 0) { /* Anything besides 0 is an error */
|
---|
747 | if(socksreq[3] == 1) {
|
---|
748 | failf(data,
|
---|
749 | "Can't complete SOCKS5 connection to %d.%d.%d.%d:%d. (%d)",
|
---|
750 | (unsigned char)socksreq[4], (unsigned char)socksreq[5],
|
---|
751 | (unsigned char)socksreq[6], (unsigned char)socksreq[7],
|
---|
752 | (((unsigned char)socksreq[8] << 8) |
|
---|
753 | (unsigned char)socksreq[9]),
|
---|
754 | (unsigned char)socksreq[1]);
|
---|
755 | }
|
---|
756 | else if(socksreq[3] == 3) {
|
---|
757 | unsigned char port_upper = (unsigned char)socksreq[len - 2];
|
---|
758 | socksreq[len - 2] = 0;
|
---|
759 | failf(data,
|
---|
760 | "Can't complete SOCKS5 connection to %s:%d. (%d)",
|
---|
761 | (char *)&socksreq[5],
|
---|
762 | ((port_upper << 8) |
|
---|
763 | (unsigned char)socksreq[len - 1]),
|
---|
764 | (unsigned char)socksreq[1]);
|
---|
765 | socksreq[len - 2] = port_upper;
|
---|
766 | }
|
---|
767 | else if(socksreq[3] == 4) {
|
---|
768 | failf(data,
|
---|
769 | "Can't complete SOCKS5 connection to %02x%02x:%02x%02x:"
|
---|
770 | "%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%02x%02x:%d. (%d)",
|
---|
771 | (unsigned char)socksreq[4], (unsigned char)socksreq[5],
|
---|
772 | (unsigned char)socksreq[6], (unsigned char)socksreq[7],
|
---|
773 | (unsigned char)socksreq[8], (unsigned char)socksreq[9],
|
---|
774 | (unsigned char)socksreq[10], (unsigned char)socksreq[11],
|
---|
775 | (unsigned char)socksreq[12], (unsigned char)socksreq[13],
|
---|
776 | (unsigned char)socksreq[14], (unsigned char)socksreq[15],
|
---|
777 | (unsigned char)socksreq[16], (unsigned char)socksreq[17],
|
---|
778 | (unsigned char)socksreq[18], (unsigned char)socksreq[19],
|
---|
779 | (((unsigned char)socksreq[20] << 8) |
|
---|
780 | (unsigned char)socksreq[21]),
|
---|
781 | (unsigned char)socksreq[1]);
|
---|
782 | }
|
---|
783 | return CURLE_COULDNT_CONNECT;
|
---|
784 | }
|
---|
785 | infof(data, "SOCKS5 request granted.\n");
|
---|
786 |
|
---|
787 | (void)curlx_nonblock(sock, TRUE);
|
---|
788 | return CURLE_OK; /* Proxy was successful! */
|
---|
789 | }
|
---|
790 |
|
---|
791 | #endif /* CURL_DISABLE_PROXY */
|
---|
792 |
|
---|