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) 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.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 | * SPDX-License-Identifier: curl
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22 | *
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23 | ***************************************************************************/
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24 |
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25 | #include "curl_setup.h"
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26 |
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27 | #if !defined(CURL_DISABLE_PROXY)
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28 |
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29 | #ifdef HAVE_NETINET_IN_H
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30 | #include <netinet/in.h>
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31 | #endif
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32 | #ifdef HAVE_ARPA_INET_H
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33 | #include <arpa/inet.h>
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34 | #endif
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35 |
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36 | #include "urldata.h"
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37 | #include "sendf.h"
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38 | #include "select.h"
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39 | #include "cfilters.h"
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40 | #include "connect.h"
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41 | #include "timeval.h"
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42 | #include "socks.h"
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43 | #include "multiif.h" /* for getsock macros */
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44 | #include "inet_pton.h"
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45 | #include "url.h"
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46 |
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47 | /* The last 3 #include files should be in this order */
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48 | #include "curl_printf.h"
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49 | #include "curl_memory.h"
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50 | #include "memdebug.h"
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51 |
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52 | /* for the (SOCKS) connect state machine */
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53 | enum connect_t {
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54 | CONNECT_INIT,
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55 | CONNECT_SOCKS_INIT, /* 1 */
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56 | CONNECT_SOCKS_SEND, /* 2 waiting to send more first data */
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57 | CONNECT_SOCKS_READ_INIT, /* 3 set up read */
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58 | CONNECT_SOCKS_READ, /* 4 read server response */
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59 | CONNECT_GSSAPI_INIT, /* 5 */
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60 | CONNECT_AUTH_INIT, /* 6 setup outgoing auth buffer */
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61 | CONNECT_AUTH_SEND, /* 7 send auth */
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62 | CONNECT_AUTH_READ, /* 8 read auth response */
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63 | CONNECT_REQ_INIT, /* 9 init SOCKS "request" */
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64 | CONNECT_RESOLVING, /* 10 */
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65 | CONNECT_RESOLVED, /* 11 */
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66 | CONNECT_RESOLVE_REMOTE, /* 12 */
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67 | CONNECT_REQ_SEND, /* 13 */
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68 | CONNECT_REQ_SENDING, /* 14 */
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69 | CONNECT_REQ_READ, /* 15 */
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70 | CONNECT_REQ_READ_MORE, /* 16 */
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71 | CONNECT_DONE /* 17 connected fine to the remote or the SOCKS proxy */
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72 | };
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73 |
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74 | #define CURL_SOCKS_BUF_SIZE 600
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75 |
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76 | /* make sure we configure it not too low */
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77 | #if CURL_SOCKS_BUF_SIZE < 600
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78 | #error CURL_SOCKS_BUF_SIZE must be at least 600
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79 | #endif
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80 |
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81 |
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82 | struct socks_state {
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83 | enum connect_t state;
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84 | ssize_t outstanding; /* send this many bytes more */
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85 | unsigned char buffer[CURL_SOCKS_BUF_SIZE];
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86 | unsigned char *outp; /* send from this pointer */
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87 |
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88 | const char *hostname;
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89 | int remote_port;
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90 | const char *proxy_user;
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91 | const char *proxy_password;
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92 | };
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93 |
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94 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
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95 | /*
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96 | * Helper read-from-socket functions. Does the same as Curl_read() but it
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97 | * blocks until all bytes amount of buffersize will be read. No more, no less.
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98 | *
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99 | * This is STUPID BLOCKING behavior. Only used by the SOCKS GSSAPI functions.
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100 | */
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101 | int Curl_blockread_all(struct Curl_cfilter *cf,
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102 | struct Curl_easy *data, /* transfer */
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103 | char *buf, /* store read data here */
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104 | ssize_t buffersize, /* max amount to read */
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105 | ssize_t *n) /* amount bytes read */
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106 | {
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107 | ssize_t nread = 0;
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108 | ssize_t allread = 0;
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109 | int result;
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110 | CURLcode err = CURLE_OK;
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111 |
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112 | *n = 0;
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113 | for(;;) {
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114 | timediff_t timeout_ms = Curl_timeleft(data, NULL, TRUE);
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115 | if(timeout_ms < 0) {
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116 | /* we already got the timeout */
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117 | result = CURLE_OPERATION_TIMEDOUT;
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118 | break;
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119 | }
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120 | if(!timeout_ms)
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121 | timeout_ms = TIMEDIFF_T_MAX;
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122 | if(SOCKET_READABLE(cf->conn->sock[cf->sockindex], timeout_ms) <= 0) {
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123 | result = ~CURLE_OK;
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124 | break;
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125 | }
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126 | nread = Curl_conn_cf_recv(cf->next, data, buf, buffersize, &err);
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127 | if(nread <= 0) {
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128 | result = err;
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129 | if(CURLE_AGAIN == err)
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130 | continue;
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131 | if(err) {
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132 | break;
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133 | }
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134 | }
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135 |
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136 | if(buffersize == nread) {
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137 | allread += nread;
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138 | *n = allread;
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139 | result = CURLE_OK;
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140 | break;
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141 | }
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142 | if(!nread) {
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143 | result = ~CURLE_OK;
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144 | break;
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145 | }
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146 |
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147 | buffersize -= nread;
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148 | buf += nread;
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149 | allread += nread;
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150 | }
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151 | return result;
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152 | }
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153 | #endif
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154 |
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155 | #if defined(DEBUGBUILD) && !defined(CURL_DISABLE_VERBOSE_STRINGS)
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156 | #define DEBUG_AND_VERBOSE
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157 | #define sxstate(x,d,y) socksstate(x,d,y, __LINE__)
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158 | #else
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159 | #define sxstate(x,d,y) socksstate(x,d,y)
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160 | #endif
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161 |
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162 | /* always use this function to change state, to make debugging easier */
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163 | static void socksstate(struct socks_state *sx, struct Curl_easy *data,
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164 | enum connect_t state
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165 | #ifdef DEBUG_AND_VERBOSE
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166 | , int lineno
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167 | #endif
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168 | )
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169 | {
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170 | enum connect_t oldstate = sx->state;
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171 | #ifdef DEBUG_AND_VERBOSE
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172 | /* synced with the state list in urldata.h */
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173 | static const char * const socks_statename[] = {
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174 | "INIT",
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175 | "SOCKS_INIT",
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176 | "SOCKS_SEND",
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177 | "SOCKS_READ_INIT",
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178 | "SOCKS_READ",
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179 | "GSSAPI_INIT",
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180 | "AUTH_INIT",
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181 | "AUTH_SEND",
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182 | "AUTH_READ",
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183 | "REQ_INIT",
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184 | "RESOLVING",
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185 | "RESOLVED",
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186 | "RESOLVE_REMOTE",
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187 | "REQ_SEND",
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188 | "REQ_SENDING",
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189 | "REQ_READ",
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190 | "REQ_READ_MORE",
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191 | "DONE"
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192 | };
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193 | #endif
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194 |
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195 | (void)data;
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196 | if(oldstate == state)
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197 | /* don't bother when the new state is the same as the old state */
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198 | return;
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199 |
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200 | sx->state = state;
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201 |
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202 | #ifdef DEBUG_AND_VERBOSE
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203 | infof(data,
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204 | "SXSTATE: %s => %s; line %d",
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205 | socks_statename[oldstate], socks_statename[sx->state],
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206 | lineno);
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207 | #endif
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208 | }
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209 |
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210 | static CURLproxycode socks_state_send(struct Curl_cfilter *cf,
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211 | struct socks_state *sx,
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212 | struct Curl_easy *data,
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213 | CURLproxycode failcode,
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214 | const char *description)
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215 | {
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216 | ssize_t nwritten;
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217 | CURLcode result;
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218 |
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219 | nwritten = Curl_conn_cf_send(cf->next, data, (char *)sx->outp,
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220 | sx->outstanding, &result);
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221 | if(nwritten <= 0) {
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222 | if(CURLE_AGAIN == result) {
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223 | return CURLPX_OK;
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224 | }
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225 | else if(CURLE_OK == result) {
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226 | /* connection closed */
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227 | failf(data, "connection to proxy closed");
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228 | return CURLPX_CLOSED;
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229 | }
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230 | failf(data, "Failed to send %s: %s", description,
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231 | curl_easy_strerror(result));
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232 | return failcode;
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233 | }
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234 | DEBUGASSERT(sx->outstanding >= nwritten);
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235 | /* not done, remain in state */
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236 | sx->outstanding -= nwritten;
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237 | sx->outp += nwritten;
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238 | return CURLPX_OK;
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239 | }
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240 |
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241 | static CURLproxycode socks_state_recv(struct Curl_cfilter *cf,
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242 | struct socks_state *sx,
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243 | struct Curl_easy *data,
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244 | CURLproxycode failcode,
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245 | const char *description)
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246 | {
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247 | ssize_t nread;
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248 | CURLcode result;
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249 |
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250 | nread = Curl_conn_cf_recv(cf->next, data, (char *)sx->outp,
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251 | sx->outstanding, &result);
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252 | if(nread <= 0) {
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253 | if(CURLE_AGAIN == result) {
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254 | return CURLPX_OK;
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255 | }
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256 | else if(CURLE_OK == result) {
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257 | /* connection closed */
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258 | failf(data, "connection to proxy closed");
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259 | return CURLPX_CLOSED;
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260 | }
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261 | failf(data, "SOCKS: Failed receiving %s: %s", description,
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262 | curl_easy_strerror(result));
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263 | return failcode;
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264 | }
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265 | /* remain in reading state */
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266 | DEBUGASSERT(sx->outstanding >= nread);
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267 | sx->outstanding -= nread;
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268 | sx->outp += nread;
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269 | return CURLPX_OK;
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270 | }
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271 |
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272 | /*
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273 | * This function logs in to a SOCKS4 proxy and sends the specifics to the final
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274 | * destination server.
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275 | *
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276 | * Reference :
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277 | * https://www.openssh.com/txt/socks4.protocol
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278 | *
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279 | * Note :
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280 | * Set protocol4a=true for "SOCKS 4A (Simple Extension to SOCKS 4 Protocol)"
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281 | * Nonsupport "Identification Protocol (RFC1413)"
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282 | */
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283 | static CURLproxycode do_SOCKS4(struct Curl_cfilter *cf,
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284 | struct socks_state *sx,
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285 | struct Curl_easy *data)
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286 | {
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287 | struct connectdata *conn = cf->conn;
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288 | const bool protocol4a =
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289 | (conn->socks_proxy.proxytype == CURLPROXY_SOCKS4A) ? TRUE : FALSE;
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290 | unsigned char *socksreq = sx->buffer;
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291 | CURLcode result;
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292 | CURLproxycode presult;
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293 | struct Curl_dns_entry *dns = NULL;
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294 |
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295 | switch(sx->state) {
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296 | case CONNECT_SOCKS_INIT:
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297 | /* SOCKS4 can only do IPv4, insist! */
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298 | conn->ip_version = CURL_IPRESOLVE_V4;
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299 | if(conn->bits.httpproxy)
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300 | infof(data, "SOCKS4%s: connecting to HTTP proxy %s port %d",
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301 | protocol4a ? "a" : "", sx->hostname, sx->remote_port);
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302 |
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303 | infof(data, "SOCKS4 communication to %s:%d",
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304 | sx->hostname, sx->remote_port);
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305 |
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306 | /*
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307 | * Compose socks4 request
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308 | *
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309 | * Request format
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310 | *
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311 | * +----+----+----+----+----+----+----+----+----+----+....+----+
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312 | * | VN | CD | DSTPORT | DSTIP | USERID |NULL|
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313 | * +----+----+----+----+----+----+----+----+----+----+....+----+
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314 | * # of bytes: 1 1 2 4 variable 1
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315 | */
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316 |
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317 | socksreq[0] = 4; /* version (SOCKS4) */
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318 | socksreq[1] = 1; /* connect */
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319 | socksreq[2] = (unsigned char)((sx->remote_port >> 8) & 0xff); /* MSB */
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320 | socksreq[3] = (unsigned char)(sx->remote_port & 0xff); /* LSB */
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321 |
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322 | /* DNS resolve only for SOCKS4, not SOCKS4a */
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323 | if(!protocol4a) {
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324 | enum resolve_t rc =
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325 | Curl_resolv(data, sx->hostname, sx->remote_port, TRUE, &dns);
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326 |
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327 | if(rc == CURLRESOLV_ERROR)
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328 | return CURLPX_RESOLVE_HOST;
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329 | else if(rc == CURLRESOLV_PENDING) {
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330 | sxstate(sx, data, CONNECT_RESOLVING);
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331 | infof(data, "SOCKS4 non-blocking resolve of %s", sx->hostname);
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332 | return CURLPX_OK;
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333 | }
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334 | sxstate(sx, data, CONNECT_RESOLVED);
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335 | goto CONNECT_RESOLVED;
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336 | }
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337 |
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338 | /* socks4a doesn't resolve anything locally */
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339 | sxstate(sx, data, CONNECT_REQ_INIT);
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340 | goto CONNECT_REQ_INIT;
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341 |
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342 | case CONNECT_RESOLVING:
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343 | /* check if we have the name resolved by now */
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344 | dns = Curl_fetch_addr(data, sx->hostname, conn->primary.remote_port);
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345 |
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346 | if(dns) {
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347 | #ifdef CURLRES_ASYNCH
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348 | data->state.async.dns = dns;
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349 | data->state.async.done = TRUE;
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350 | #endif
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351 | infof(data, "Hostname '%s' was found", sx->hostname);
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352 | sxstate(sx, data, CONNECT_RESOLVED);
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353 | }
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354 | else {
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355 | result = Curl_resolv_check(data, &dns);
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356 | if(!dns) {
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357 | if(result)
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358 | return CURLPX_RESOLVE_HOST;
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359 | return CURLPX_OK;
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360 | }
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361 | }
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362 | FALLTHROUGH();
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363 | case CONNECT_RESOLVED:
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364 | CONNECT_RESOLVED:
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365 | {
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366 | struct Curl_addrinfo *hp = NULL;
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367 | /*
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368 | * We cannot use 'hostent' as a struct that Curl_resolv() returns. It
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369 | * returns a Curl_addrinfo pointer that may not always look the same.
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370 | */
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371 | if(dns) {
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372 | hp = dns->addr;
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373 |
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374 | /* scan for the first IPv4 address */
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375 | while(hp && (hp->ai_family != AF_INET))
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376 | hp = hp->ai_next;
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377 |
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378 | if(hp) {
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379 | struct sockaddr_in *saddr_in;
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380 | char buf[64];
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381 | Curl_printable_address(hp, buf, sizeof(buf));
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382 |
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383 | saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
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384 | socksreq[4] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[0];
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385 | socksreq[5] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[1];
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386 | socksreq[6] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[2];
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387 | socksreq[7] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[3];
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388 |
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389 | infof(data, "SOCKS4 connect to IPv4 %s (locally resolved)", buf);
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390 |
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391 | Curl_resolv_unlock(data, dns); /* not used anymore from now on */
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392 | }
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393 | else
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394 | failf(data, "SOCKS4 connection to %s not supported", sx->hostname);
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395 | }
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396 | else
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397 | failf(data, "Failed to resolve \"%s\" for SOCKS4 connect.",
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398 | sx->hostname);
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399 |
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400 | if(!hp)
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401 | return CURLPX_RESOLVE_HOST;
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402 | }
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403 | FALLTHROUGH();
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404 | case CONNECT_REQ_INIT:
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405 | CONNECT_REQ_INIT:
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406 | /*
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407 | * This is currently not supporting "Identification Protocol (RFC1413)".
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408 | */
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409 | socksreq[8] = 0; /* ensure empty userid is NUL-terminated */
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410 | if(sx->proxy_user) {
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411 | size_t plen = strlen(sx->proxy_user);
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412 | if(plen > 255) {
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413 | /* there is no real size limit to this field in the protocol, but
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414 | SOCKS5 limits the proxy user field to 255 bytes and it seems likely
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415 | that a longer field is either a mistake or malicious input */
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416 | failf(data, "Too long SOCKS proxy user name");
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417 | return CURLPX_LONG_USER;
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418 | }
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419 | /* copy the proxy name WITH trailing zero */
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420 | memcpy(socksreq + 8, sx->proxy_user, plen + 1);
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421 | }
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422 |
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423 | /*
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424 | * Make connection
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425 | */
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426 | {
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427 | size_t packetsize = 9 +
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428 | strlen((char *)socksreq + 8); /* size including NUL */
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429 |
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430 | /* If SOCKS4a, set special invalid IP address 0.0.0.x */
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431 | if(protocol4a) {
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432 | size_t hostnamelen = 0;
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433 | socksreq[4] = 0;
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434 | socksreq[5] = 0;
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435 | socksreq[6] = 0;
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436 | socksreq[7] = 1;
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437 | /* append hostname */
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438 | hostnamelen = strlen(sx->hostname) + 1; /* length including NUL */
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439 | if((hostnamelen <= 255) &&
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440 | (packetsize + hostnamelen < sizeof(sx->buffer)))
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441 | strcpy((char *)socksreq + packetsize, sx->hostname);
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442 | else {
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443 | failf(data, "SOCKS4: too long host name");
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444 | return CURLPX_LONG_HOSTNAME;
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445 | }
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446 | packetsize += hostnamelen;
|
---|
447 | }
|
---|
448 | sx->outp = socksreq;
|
---|
449 | DEBUGASSERT(packetsize <= sizeof(sx->buffer));
|
---|
450 | sx->outstanding = packetsize;
|
---|
451 | sxstate(sx, data, CONNECT_REQ_SENDING);
|
---|
452 | }
|
---|
453 | FALLTHROUGH();
|
---|
454 | case CONNECT_REQ_SENDING:
|
---|
455 | /* Send request */
|
---|
456 | presult = socks_state_send(cf, sx, data, CURLPX_SEND_CONNECT,
|
---|
457 | "SOCKS4 connect request");
|
---|
458 | if(CURLPX_OK != presult)
|
---|
459 | return presult;
|
---|
460 | else if(sx->outstanding) {
|
---|
461 | /* remain in sending state */
|
---|
462 | return CURLPX_OK;
|
---|
463 | }
|
---|
464 | /* done sending! */
|
---|
465 | sx->outstanding = 8; /* receive data size */
|
---|
466 | sx->outp = socksreq;
|
---|
467 | sxstate(sx, data, CONNECT_SOCKS_READ);
|
---|
468 |
|
---|
469 | FALLTHROUGH();
|
---|
470 | case CONNECT_SOCKS_READ:
|
---|
471 | /* Receive response */
|
---|
472 | presult = socks_state_recv(cf, sx, data, CURLPX_RECV_CONNECT,
|
---|
473 | "connect request ack");
|
---|
474 | if(CURLPX_OK != presult)
|
---|
475 | return presult;
|
---|
476 | else if(sx->outstanding) {
|
---|
477 | /* remain in reading state */
|
---|
478 | return CURLPX_OK;
|
---|
479 | }
|
---|
480 | sxstate(sx, data, CONNECT_DONE);
|
---|
481 | break;
|
---|
482 | default: /* lots of unused states in SOCKS4 */
|
---|
483 | break;
|
---|
484 | }
|
---|
485 |
|
---|
486 | /*
|
---|
487 | * Response format
|
---|
488 | *
|
---|
489 | * +----+----+----+----+----+----+----+----+
|
---|
490 | * | VN | CD | DSTPORT | DSTIP |
|
---|
491 | * +----+----+----+----+----+----+----+----+
|
---|
492 | * # of bytes: 1 1 2 4
|
---|
493 | *
|
---|
494 | * VN is the version of the reply code and should be 0. CD is the result
|
---|
495 | * code with one of the following values:
|
---|
496 | *
|
---|
497 | * 90: request granted
|
---|
498 | * 91: request rejected or failed
|
---|
499 | * 92: request rejected because SOCKS server cannot connect to
|
---|
500 | * identd on the client
|
---|
501 | * 93: request rejected because the client program and identd
|
---|
502 | * report different user-ids
|
---|
503 | */
|
---|
504 |
|
---|
505 | /* wrong version ? */
|
---|
506 | if(socksreq[0]) {
|
---|
507 | failf(data,
|
---|
508 | "SOCKS4 reply has wrong version, version should be 0.");
|
---|
509 | return CURLPX_BAD_VERSION;
|
---|
510 | }
|
---|
511 |
|
---|
512 | /* Result */
|
---|
513 | switch(socksreq[1]) {
|
---|
514 | case 90:
|
---|
515 | infof(data, "SOCKS4%s request granted.", protocol4a?"a":"");
|
---|
516 | break;
|
---|
517 | case 91:
|
---|
518 | failf(data,
|
---|
519 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
|
---|
520 | ", request rejected or failed.",
|
---|
521 | socksreq[4], socksreq[5], socksreq[6], socksreq[7],
|
---|
522 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
|
---|
523 | (unsigned char)socksreq[1]);
|
---|
524 | return CURLPX_REQUEST_FAILED;
|
---|
525 | case 92:
|
---|
526 | failf(data,
|
---|
527 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
|
---|
528 | ", request rejected because SOCKS server cannot connect to "
|
---|
529 | "identd on the client.",
|
---|
530 | socksreq[4], socksreq[5], socksreq[6], socksreq[7],
|
---|
531 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
|
---|
532 | (unsigned char)socksreq[1]);
|
---|
533 | return CURLPX_IDENTD;
|
---|
534 | case 93:
|
---|
535 | failf(data,
|
---|
536 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
|
---|
537 | ", request rejected because the client program and identd "
|
---|
538 | "report different user-ids.",
|
---|
539 | socksreq[4], socksreq[5], socksreq[6], socksreq[7],
|
---|
540 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
|
---|
541 | (unsigned char)socksreq[1]);
|
---|
542 | return CURLPX_IDENTD_DIFFER;
|
---|
543 | default:
|
---|
544 | failf(data,
|
---|
545 | "Can't complete SOCKS4 connection to %d.%d.%d.%d:%d. (%d)"
|
---|
546 | ", Unknown.",
|
---|
547 | socksreq[4], socksreq[5], socksreq[6], socksreq[7],
|
---|
548 | (((unsigned char)socksreq[2] << 8) | (unsigned char)socksreq[3]),
|
---|
549 | (unsigned char)socksreq[1]);
|
---|
550 | return CURLPX_UNKNOWN_FAIL;
|
---|
551 | }
|
---|
552 |
|
---|
553 | return CURLPX_OK; /* Proxy was successful! */
|
---|
554 | }
|
---|
555 |
|
---|
556 | /*
|
---|
557 | * This function logs in to a SOCKS5 proxy and sends the specifics to the final
|
---|
558 | * destination server.
|
---|
559 | */
|
---|
560 | static CURLproxycode do_SOCKS5(struct Curl_cfilter *cf,
|
---|
561 | struct socks_state *sx,
|
---|
562 | struct Curl_easy *data)
|
---|
563 | {
|
---|
564 | /*
|
---|
565 | According to the RFC1928, section "6. Replies". This is what a SOCK5
|
---|
566 | replies:
|
---|
567 |
|
---|
568 | +----+-----+-------+------+----------+----------+
|
---|
569 | |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
|
---|
570 | +----+-----+-------+------+----------+----------+
|
---|
571 | | 1 | 1 | X'00' | 1 | Variable | 2 |
|
---|
572 | +----+-----+-------+------+----------+----------+
|
---|
573 |
|
---|
574 | Where:
|
---|
575 |
|
---|
576 | o VER protocol version: X'05'
|
---|
577 | o REP Reply field:
|
---|
578 | o X'00' succeeded
|
---|
579 | */
|
---|
580 | struct connectdata *conn = cf->conn;
|
---|
581 | unsigned char *socksreq = sx->buffer;
|
---|
582 | size_t idx;
|
---|
583 | CURLcode result;
|
---|
584 | CURLproxycode presult;
|
---|
585 | bool socks5_resolve_local =
|
---|
586 | (conn->socks_proxy.proxytype == CURLPROXY_SOCKS5) ? TRUE : FALSE;
|
---|
587 | const size_t hostname_len = strlen(sx->hostname);
|
---|
588 | size_t len = 0;
|
---|
589 | const unsigned char auth = data->set.socks5auth;
|
---|
590 | bool allow_gssapi = FALSE;
|
---|
591 | struct Curl_dns_entry *dns = NULL;
|
---|
592 |
|
---|
593 | DEBUGASSERT(auth & (CURLAUTH_BASIC | CURLAUTH_GSSAPI));
|
---|
594 | switch(sx->state) {
|
---|
595 | case CONNECT_SOCKS_INIT:
|
---|
596 | if(conn->bits.httpproxy)
|
---|
597 | infof(data, "SOCKS5: connecting to HTTP proxy %s port %d",
|
---|
598 | sx->hostname, sx->remote_port);
|
---|
599 |
|
---|
600 | /* RFC1928 chapter 5 specifies max 255 chars for domain name in packet */
|
---|
601 | if(!socks5_resolve_local && hostname_len > 255) {
|
---|
602 | failf(data, "SOCKS5: the destination hostname is too long to be "
|
---|
603 | "resolved remotely by the proxy.");
|
---|
604 | return CURLPX_LONG_HOSTNAME;
|
---|
605 | }
|
---|
606 |
|
---|
607 | if(auth & ~(CURLAUTH_BASIC | CURLAUTH_GSSAPI))
|
---|
608 | infof(data,
|
---|
609 | "warning: unsupported value passed to CURLOPT_SOCKS5_AUTH: %u",
|
---|
610 | auth);
|
---|
611 | if(!(auth & CURLAUTH_BASIC))
|
---|
612 | /* disable username/password auth */
|
---|
613 | sx->proxy_user = NULL;
|
---|
614 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
615 | if(auth & CURLAUTH_GSSAPI)
|
---|
616 | allow_gssapi = TRUE;
|
---|
617 | #endif
|
---|
618 |
|
---|
619 | idx = 0;
|
---|
620 | socksreq[idx++] = 5; /* version */
|
---|
621 | idx++; /* number of authentication methods */
|
---|
622 | socksreq[idx++] = 0; /* no authentication */
|
---|
623 | if(allow_gssapi)
|
---|
624 | socksreq[idx++] = 1; /* GSS-API */
|
---|
625 | if(sx->proxy_user)
|
---|
626 | socksreq[idx++] = 2; /* username/password */
|
---|
627 | /* write the number of authentication methods */
|
---|
628 | socksreq[1] = (unsigned char) (idx - 2);
|
---|
629 |
|
---|
630 | sx->outp = socksreq;
|
---|
631 | DEBUGASSERT(idx <= sizeof(sx->buffer));
|
---|
632 | sx->outstanding = idx;
|
---|
633 | presult = socks_state_send(cf, sx, data, CURLPX_SEND_CONNECT,
|
---|
634 | "initial SOCKS5 request");
|
---|
635 | if(CURLPX_OK != presult)
|
---|
636 | return presult;
|
---|
637 | else if(sx->outstanding) {
|
---|
638 | /* remain in sending state */
|
---|
639 | return CURLPX_OK;
|
---|
640 | }
|
---|
641 | sxstate(sx, data, CONNECT_SOCKS_READ);
|
---|
642 | goto CONNECT_SOCKS_READ_INIT;
|
---|
643 | case CONNECT_SOCKS_SEND:
|
---|
644 | presult = socks_state_send(cf, sx, data, CURLPX_SEND_CONNECT,
|
---|
645 | "initial SOCKS5 request");
|
---|
646 | if(CURLPX_OK != presult)
|
---|
647 | return presult;
|
---|
648 | else if(sx->outstanding) {
|
---|
649 | /* remain in sending state */
|
---|
650 | return CURLPX_OK;
|
---|
651 | }
|
---|
652 | FALLTHROUGH();
|
---|
653 | case CONNECT_SOCKS_READ_INIT:
|
---|
654 | CONNECT_SOCKS_READ_INIT:
|
---|
655 | sx->outstanding = 2; /* expect two bytes */
|
---|
656 | sx->outp = socksreq; /* store it here */
|
---|
657 | FALLTHROUGH();
|
---|
658 | case CONNECT_SOCKS_READ:
|
---|
659 | presult = socks_state_recv(cf, sx, data, CURLPX_RECV_CONNECT,
|
---|
660 | "initial SOCKS5 response");
|
---|
661 | if(CURLPX_OK != presult)
|
---|
662 | return presult;
|
---|
663 | else if(sx->outstanding) {
|
---|
664 | /* remain in reading state */
|
---|
665 | return CURLPX_OK;
|
---|
666 | }
|
---|
667 | else if(socksreq[0] != 5) {
|
---|
668 | failf(data, "Received invalid version in initial SOCKS5 response.");
|
---|
669 | return CURLPX_BAD_VERSION;
|
---|
670 | }
|
---|
671 | else if(socksreq[1] == 0) {
|
---|
672 | /* DONE! No authentication needed. Send request. */
|
---|
673 | sxstate(sx, data, CONNECT_REQ_INIT);
|
---|
674 | goto CONNECT_REQ_INIT;
|
---|
675 | }
|
---|
676 | else if(socksreq[1] == 2) {
|
---|
677 | /* regular name + password authentication */
|
---|
678 | sxstate(sx, data, CONNECT_AUTH_INIT);
|
---|
679 | goto CONNECT_AUTH_INIT;
|
---|
680 | }
|
---|
681 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
682 | else if(allow_gssapi && (socksreq[1] == 1)) {
|
---|
683 | sxstate(sx, data, CONNECT_GSSAPI_INIT);
|
---|
684 | result = Curl_SOCKS5_gssapi_negotiate(cf, data);
|
---|
685 | if(result) {
|
---|
686 | failf(data, "Unable to negotiate SOCKS5 GSS-API context.");
|
---|
687 | return CURLPX_GSSAPI;
|
---|
688 | }
|
---|
689 | }
|
---|
690 | #endif
|
---|
691 | else {
|
---|
692 | /* error */
|
---|
693 | if(!allow_gssapi && (socksreq[1] == 1)) {
|
---|
694 | failf(data,
|
---|
695 | "SOCKS5 GSSAPI per-message authentication is not supported.");
|
---|
696 | return CURLPX_GSSAPI_PERMSG;
|
---|
697 | }
|
---|
698 | else if(socksreq[1] == 255) {
|
---|
699 | failf(data, "No authentication method was acceptable.");
|
---|
700 | return CURLPX_NO_AUTH;
|
---|
701 | }
|
---|
702 | }
|
---|
703 | failf(data,
|
---|
704 | "Undocumented SOCKS5 mode attempted to be used by server.");
|
---|
705 | return CURLPX_UNKNOWN_MODE;
|
---|
706 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
707 | case CONNECT_GSSAPI_INIT:
|
---|
708 | /* GSSAPI stuff done non-blocking */
|
---|
709 | break;
|
---|
710 | #endif
|
---|
711 |
|
---|
712 | default: /* do nothing! */
|
---|
713 | break;
|
---|
714 |
|
---|
715 | CONNECT_AUTH_INIT:
|
---|
716 | case CONNECT_AUTH_INIT: {
|
---|
717 | /* Needs user name and password */
|
---|
718 | size_t proxy_user_len, proxy_password_len;
|
---|
719 | if(sx->proxy_user && sx->proxy_password) {
|
---|
720 | proxy_user_len = strlen(sx->proxy_user);
|
---|
721 | proxy_password_len = strlen(sx->proxy_password);
|
---|
722 | }
|
---|
723 | else {
|
---|
724 | proxy_user_len = 0;
|
---|
725 | proxy_password_len = 0;
|
---|
726 | }
|
---|
727 |
|
---|
728 | /* username/password request looks like
|
---|
729 | * +----+------+----------+------+----------+
|
---|
730 | * |VER | ULEN | UNAME | PLEN | PASSWD |
|
---|
731 | * +----+------+----------+------+----------+
|
---|
732 | * | 1 | 1 | 1 to 255 | 1 | 1 to 255 |
|
---|
733 | * +----+------+----------+------+----------+
|
---|
734 | */
|
---|
735 | len = 0;
|
---|
736 | socksreq[len++] = 1; /* username/pw subnegotiation version */
|
---|
737 | socksreq[len++] = (unsigned char) proxy_user_len;
|
---|
738 | if(sx->proxy_user && proxy_user_len) {
|
---|
739 | /* the length must fit in a single byte */
|
---|
740 | if(proxy_user_len > 255) {
|
---|
741 | failf(data, "Excessive user name length for proxy auth");
|
---|
742 | return CURLPX_LONG_USER;
|
---|
743 | }
|
---|
744 | memcpy(socksreq + len, sx->proxy_user, proxy_user_len);
|
---|
745 | }
|
---|
746 | len += proxy_user_len;
|
---|
747 | socksreq[len++] = (unsigned char) proxy_password_len;
|
---|
748 | if(sx->proxy_password && proxy_password_len) {
|
---|
749 | /* the length must fit in a single byte */
|
---|
750 | if(proxy_password_len > 255) {
|
---|
751 | failf(data, "Excessive password length for proxy auth");
|
---|
752 | return CURLPX_LONG_PASSWD;
|
---|
753 | }
|
---|
754 | memcpy(socksreq + len, sx->proxy_password, proxy_password_len);
|
---|
755 | }
|
---|
756 | len += proxy_password_len;
|
---|
757 | sxstate(sx, data, CONNECT_AUTH_SEND);
|
---|
758 | DEBUGASSERT(len <= sizeof(sx->buffer));
|
---|
759 | sx->outstanding = len;
|
---|
760 | sx->outp = socksreq;
|
---|
761 | }
|
---|
762 | FALLTHROUGH();
|
---|
763 | case CONNECT_AUTH_SEND:
|
---|
764 | presult = socks_state_send(cf, sx, data, CURLPX_SEND_AUTH,
|
---|
765 | "SOCKS5 sub-negotiation request");
|
---|
766 | if(CURLPX_OK != presult)
|
---|
767 | return presult;
|
---|
768 | else if(sx->outstanding) {
|
---|
769 | /* remain in sending state */
|
---|
770 | return CURLPX_OK;
|
---|
771 | }
|
---|
772 | sx->outp = socksreq;
|
---|
773 | sx->outstanding = 2;
|
---|
774 | sxstate(sx, data, CONNECT_AUTH_READ);
|
---|
775 | FALLTHROUGH();
|
---|
776 | case CONNECT_AUTH_READ:
|
---|
777 | presult = socks_state_recv(cf, sx, data, CURLPX_RECV_AUTH,
|
---|
778 | "SOCKS5 sub-negotiation response");
|
---|
779 | if(CURLPX_OK != presult)
|
---|
780 | return presult;
|
---|
781 | else if(sx->outstanding) {
|
---|
782 | /* remain in reading state */
|
---|
783 | return CURLPX_OK;
|
---|
784 | }
|
---|
785 | /* ignore the first (VER) byte */
|
---|
786 | else if(socksreq[1]) { /* status */
|
---|
787 | failf(data, "User was rejected by the SOCKS5 server (%d %d).",
|
---|
788 | socksreq[0], socksreq[1]);
|
---|
789 | return CURLPX_USER_REJECTED;
|
---|
790 | }
|
---|
791 |
|
---|
792 | /* Everything is good so far, user was authenticated! */
|
---|
793 | sxstate(sx, data, CONNECT_REQ_INIT);
|
---|
794 | FALLTHROUGH();
|
---|
795 | case CONNECT_REQ_INIT:
|
---|
796 | CONNECT_REQ_INIT:
|
---|
797 | if(socks5_resolve_local) {
|
---|
798 | enum resolve_t rc = Curl_resolv(data, sx->hostname, sx->remote_port,
|
---|
799 | TRUE, &dns);
|
---|
800 |
|
---|
801 | if(rc == CURLRESOLV_ERROR)
|
---|
802 | return CURLPX_RESOLVE_HOST;
|
---|
803 |
|
---|
804 | if(rc == CURLRESOLV_PENDING) {
|
---|
805 | sxstate(sx, data, CONNECT_RESOLVING);
|
---|
806 | return CURLPX_OK;
|
---|
807 | }
|
---|
808 | sxstate(sx, data, CONNECT_RESOLVED);
|
---|
809 | goto CONNECT_RESOLVED;
|
---|
810 | }
|
---|
811 | goto CONNECT_RESOLVE_REMOTE;
|
---|
812 |
|
---|
813 | case CONNECT_RESOLVING:
|
---|
814 | /* check if we have the name resolved by now */
|
---|
815 | dns = Curl_fetch_addr(data, sx->hostname, sx->remote_port);
|
---|
816 |
|
---|
817 | if(dns) {
|
---|
818 | #ifdef CURLRES_ASYNCH
|
---|
819 | data->state.async.dns = dns;
|
---|
820 | data->state.async.done = TRUE;
|
---|
821 | #endif
|
---|
822 | infof(data, "SOCKS5: hostname '%s' found", sx->hostname);
|
---|
823 | }
|
---|
824 |
|
---|
825 | if(!dns) {
|
---|
826 | result = Curl_resolv_check(data, &dns);
|
---|
827 | if(!dns) {
|
---|
828 | if(result)
|
---|
829 | return CURLPX_RESOLVE_HOST;
|
---|
830 | return CURLPX_OK;
|
---|
831 | }
|
---|
832 | }
|
---|
833 | FALLTHROUGH();
|
---|
834 | case CONNECT_RESOLVED:
|
---|
835 | CONNECT_RESOLVED:
|
---|
836 | {
|
---|
837 | char dest[MAX_IPADR_LEN]; /* printable address */
|
---|
838 | struct Curl_addrinfo *hp = NULL;
|
---|
839 | if(dns)
|
---|
840 | hp = dns->addr;
|
---|
841 | #ifdef ENABLE_IPV6
|
---|
842 | if(data->set.ipver != CURL_IPRESOLVE_WHATEVER) {
|
---|
843 | int wanted_family = data->set.ipver == CURL_IPRESOLVE_V4 ?
|
---|
844 | AF_INET : AF_INET6;
|
---|
845 | /* scan for the first proper address */
|
---|
846 | while(hp && (hp->ai_family != wanted_family))
|
---|
847 | hp = hp->ai_next;
|
---|
848 | }
|
---|
849 | #endif
|
---|
850 | if(!hp) {
|
---|
851 | failf(data, "Failed to resolve \"%s\" for SOCKS5 connect.",
|
---|
852 | sx->hostname);
|
---|
853 | return CURLPX_RESOLVE_HOST;
|
---|
854 | }
|
---|
855 |
|
---|
856 | Curl_printable_address(hp, dest, sizeof(dest));
|
---|
857 |
|
---|
858 | len = 0;
|
---|
859 | socksreq[len++] = 5; /* version (SOCKS5) */
|
---|
860 | socksreq[len++] = 1; /* connect */
|
---|
861 | socksreq[len++] = 0; /* must be zero */
|
---|
862 | if(hp->ai_family == AF_INET) {
|
---|
863 | int i;
|
---|
864 | struct sockaddr_in *saddr_in;
|
---|
865 | socksreq[len++] = 1; /* ATYP: IPv4 = 1 */
|
---|
866 |
|
---|
867 | saddr_in = (struct sockaddr_in *)(void *)hp->ai_addr;
|
---|
868 | for(i = 0; i < 4; i++) {
|
---|
869 | socksreq[len++] = ((unsigned char *)&saddr_in->sin_addr.s_addr)[i];
|
---|
870 | }
|
---|
871 |
|
---|
872 | infof(data, "SOCKS5 connect to %s:%d (locally resolved)", dest,
|
---|
873 | sx->remote_port);
|
---|
874 | }
|
---|
875 | #ifdef ENABLE_IPV6
|
---|
876 | else if(hp->ai_family == AF_INET6) {
|
---|
877 | int i;
|
---|
878 | struct sockaddr_in6 *saddr_in6;
|
---|
879 | socksreq[len++] = 4; /* ATYP: IPv6 = 4 */
|
---|
880 |
|
---|
881 | saddr_in6 = (struct sockaddr_in6 *)(void *)hp->ai_addr;
|
---|
882 | for(i = 0; i < 16; i++) {
|
---|
883 | socksreq[len++] =
|
---|
884 | ((unsigned char *)&saddr_in6->sin6_addr.s6_addr)[i];
|
---|
885 | }
|
---|
886 |
|
---|
887 | infof(data, "SOCKS5 connect to [%s]:%d (locally resolved)", dest,
|
---|
888 | sx->remote_port);
|
---|
889 | }
|
---|
890 | #endif
|
---|
891 | else {
|
---|
892 | hp = NULL; /* fail! */
|
---|
893 | failf(data, "SOCKS5 connection to %s not supported", dest);
|
---|
894 | }
|
---|
895 |
|
---|
896 | Curl_resolv_unlock(data, dns); /* not used anymore from now on */
|
---|
897 | goto CONNECT_REQ_SEND;
|
---|
898 | }
|
---|
899 | CONNECT_RESOLVE_REMOTE:
|
---|
900 | case CONNECT_RESOLVE_REMOTE:
|
---|
901 | /* Authentication is complete, now specify destination to the proxy */
|
---|
902 | len = 0;
|
---|
903 | socksreq[len++] = 5; /* version (SOCKS5) */
|
---|
904 | socksreq[len++] = 1; /* connect */
|
---|
905 | socksreq[len++] = 0; /* must be zero */
|
---|
906 |
|
---|
907 | if(!socks5_resolve_local) {
|
---|
908 | /* ATYP: domain name = 3,
|
---|
909 | IPv6 == 4,
|
---|
910 | IPv4 == 1 */
|
---|
911 | unsigned char ip4[4];
|
---|
912 | #ifdef ENABLE_IPV6
|
---|
913 | if(conn->bits.ipv6_ip) {
|
---|
914 | char ip6[16];
|
---|
915 | if(1 != Curl_inet_pton(AF_INET6, sx->hostname, ip6))
|
---|
916 | return CURLPX_BAD_ADDRESS_TYPE;
|
---|
917 | socksreq[len++] = 4;
|
---|
918 | memcpy(&socksreq[len], ip6, sizeof(ip6));
|
---|
919 | len += sizeof(ip6);
|
---|
920 | }
|
---|
921 | else
|
---|
922 | #endif
|
---|
923 | if(1 == Curl_inet_pton(AF_INET, sx->hostname, ip4)) {
|
---|
924 | socksreq[len++] = 1;
|
---|
925 | memcpy(&socksreq[len], ip4, sizeof(ip4));
|
---|
926 | len += sizeof(ip4);
|
---|
927 | }
|
---|
928 | else {
|
---|
929 | socksreq[len++] = 3;
|
---|
930 | socksreq[len++] = (unsigned char) hostname_len; /* one byte length */
|
---|
931 | memcpy(&socksreq[len], sx->hostname, hostname_len); /* w/o NULL */
|
---|
932 | len += hostname_len;
|
---|
933 | }
|
---|
934 | infof(data, "SOCKS5 connect to %s:%d (remotely resolved)",
|
---|
935 | sx->hostname, sx->remote_port);
|
---|
936 | }
|
---|
937 | FALLTHROUGH();
|
---|
938 |
|
---|
939 | case CONNECT_REQ_SEND:
|
---|
940 | CONNECT_REQ_SEND:
|
---|
941 | /* PORT MSB */
|
---|
942 | socksreq[len++] = (unsigned char)((sx->remote_port >> 8) & 0xff);
|
---|
943 | /* PORT LSB */
|
---|
944 | socksreq[len++] = (unsigned char)(sx->remote_port & 0xff);
|
---|
945 |
|
---|
946 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
947 | if(conn->socks5_gssapi_enctype) {
|
---|
948 | failf(data, "SOCKS5 GSS-API protection not yet implemented.");
|
---|
949 | return CURLPX_GSSAPI_PROTECTION;
|
---|
950 | }
|
---|
951 | #endif
|
---|
952 | sx->outp = socksreq;
|
---|
953 | DEBUGASSERT(len <= sizeof(sx->buffer));
|
---|
954 | sx->outstanding = len;
|
---|
955 | sxstate(sx, data, CONNECT_REQ_SENDING);
|
---|
956 | FALLTHROUGH();
|
---|
957 | case CONNECT_REQ_SENDING:
|
---|
958 | presult = socks_state_send(cf, sx, data, CURLPX_SEND_REQUEST,
|
---|
959 | "SOCKS5 connect request");
|
---|
960 | if(CURLPX_OK != presult)
|
---|
961 | return presult;
|
---|
962 | else if(sx->outstanding) {
|
---|
963 | /* remain in send state */
|
---|
964 | return CURLPX_OK;
|
---|
965 | }
|
---|
966 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
967 | if(conn->socks5_gssapi_enctype) {
|
---|
968 | failf(data, "SOCKS5 GSS-API protection not yet implemented.");
|
---|
969 | return CURLPX_GSSAPI_PROTECTION;
|
---|
970 | }
|
---|
971 | #endif
|
---|
972 | sx->outstanding = 10; /* minimum packet size is 10 */
|
---|
973 | sx->outp = socksreq;
|
---|
974 | sxstate(sx, data, CONNECT_REQ_READ);
|
---|
975 | FALLTHROUGH();
|
---|
976 | case CONNECT_REQ_READ:
|
---|
977 | presult = socks_state_recv(cf, sx, data, CURLPX_RECV_REQACK,
|
---|
978 | "SOCKS5 connect request ack");
|
---|
979 | if(CURLPX_OK != presult)
|
---|
980 | return presult;
|
---|
981 | else if(sx->outstanding) {
|
---|
982 | /* remain in reading state */
|
---|
983 | return CURLPX_OK;
|
---|
984 | }
|
---|
985 | else if(socksreq[0] != 5) { /* version */
|
---|
986 | failf(data,
|
---|
987 | "SOCKS5 reply has wrong version, version should be 5.");
|
---|
988 | return CURLPX_BAD_VERSION;
|
---|
989 | }
|
---|
990 | else if(socksreq[1]) { /* Anything besides 0 is an error */
|
---|
991 | CURLproxycode rc = CURLPX_REPLY_UNASSIGNED;
|
---|
992 | int code = socksreq[1];
|
---|
993 | failf(data, "Can't complete SOCKS5 connection to %s. (%d)",
|
---|
994 | sx->hostname, (unsigned char)socksreq[1]);
|
---|
995 | if(code < 9) {
|
---|
996 | /* RFC 1928 section 6 lists: */
|
---|
997 | static const CURLproxycode lookup[] = {
|
---|
998 | CURLPX_OK,
|
---|
999 | CURLPX_REPLY_GENERAL_SERVER_FAILURE,
|
---|
1000 | CURLPX_REPLY_NOT_ALLOWED,
|
---|
1001 | CURLPX_REPLY_NETWORK_UNREACHABLE,
|
---|
1002 | CURLPX_REPLY_HOST_UNREACHABLE,
|
---|
1003 | CURLPX_REPLY_CONNECTION_REFUSED,
|
---|
1004 | CURLPX_REPLY_TTL_EXPIRED,
|
---|
1005 | CURLPX_REPLY_COMMAND_NOT_SUPPORTED,
|
---|
1006 | CURLPX_REPLY_ADDRESS_TYPE_NOT_SUPPORTED,
|
---|
1007 | };
|
---|
1008 | rc = lookup[code];
|
---|
1009 | }
|
---|
1010 | return rc;
|
---|
1011 | }
|
---|
1012 |
|
---|
1013 | /* Fix: in general, returned BND.ADDR is variable length parameter by RFC
|
---|
1014 | 1928, so the reply packet should be read until the end to avoid errors
|
---|
1015 | at subsequent protocol level.
|
---|
1016 |
|
---|
1017 | +----+-----+-------+------+----------+----------+
|
---|
1018 | |VER | REP | RSV | ATYP | BND.ADDR | BND.PORT |
|
---|
1019 | +----+-----+-------+------+----------+----------+
|
---|
1020 | | 1 | 1 | X'00' | 1 | Variable | 2 |
|
---|
1021 | +----+-----+-------+------+----------+----------+
|
---|
1022 |
|
---|
1023 | ATYP:
|
---|
1024 | o IP v4 address: X'01', BND.ADDR = 4 byte
|
---|
1025 | o domain name: X'03', BND.ADDR = [ 1 byte length, string ]
|
---|
1026 | o IP v6 address: X'04', BND.ADDR = 16 byte
|
---|
1027 | */
|
---|
1028 |
|
---|
1029 | /* Calculate real packet size */
|
---|
1030 | if(socksreq[3] == 3) {
|
---|
1031 | /* domain name */
|
---|
1032 | int addrlen = (int) socksreq[4];
|
---|
1033 | len = 5 + addrlen + 2;
|
---|
1034 | }
|
---|
1035 | else if(socksreq[3] == 4) {
|
---|
1036 | /* IPv6 */
|
---|
1037 | len = 4 + 16 + 2;
|
---|
1038 | }
|
---|
1039 | else if(socksreq[3] == 1) {
|
---|
1040 | len = 4 + 4 + 2;
|
---|
1041 | }
|
---|
1042 | else {
|
---|
1043 | failf(data, "SOCKS5 reply has wrong address type.");
|
---|
1044 | return CURLPX_BAD_ADDRESS_TYPE;
|
---|
1045 | }
|
---|
1046 |
|
---|
1047 | /* At this point we already read first 10 bytes */
|
---|
1048 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
1049 | if(!conn->socks5_gssapi_enctype) {
|
---|
1050 | /* decrypt_gssapi_blockread already read the whole packet */
|
---|
1051 | #endif
|
---|
1052 | if(len > 10) {
|
---|
1053 | DEBUGASSERT(len <= sizeof(sx->buffer));
|
---|
1054 | sx->outstanding = len - 10; /* get the rest */
|
---|
1055 | sx->outp = &socksreq[10];
|
---|
1056 | sxstate(sx, data, CONNECT_REQ_READ_MORE);
|
---|
1057 | }
|
---|
1058 | else {
|
---|
1059 | sxstate(sx, data, CONNECT_DONE);
|
---|
1060 | break;
|
---|
1061 | }
|
---|
1062 | #if defined(HAVE_GSSAPI) || defined(USE_WINDOWS_SSPI)
|
---|
1063 | }
|
---|
1064 | #endif
|
---|
1065 | FALLTHROUGH();
|
---|
1066 | case CONNECT_REQ_READ_MORE:
|
---|
1067 | presult = socks_state_recv(cf, sx, data, CURLPX_RECV_ADDRESS,
|
---|
1068 | "SOCKS5 connect request address");
|
---|
1069 | if(CURLPX_OK != presult)
|
---|
1070 | return presult;
|
---|
1071 | else if(sx->outstanding) {
|
---|
1072 | /* remain in reading state */
|
---|
1073 | return CURLPX_OK;
|
---|
1074 | }
|
---|
1075 | sxstate(sx, data, CONNECT_DONE);
|
---|
1076 | }
|
---|
1077 | infof(data, "SOCKS5 request granted.");
|
---|
1078 |
|
---|
1079 | return CURLPX_OK; /* Proxy was successful! */
|
---|
1080 | }
|
---|
1081 |
|
---|
1082 | static CURLcode connect_SOCKS(struct Curl_cfilter *cf,
|
---|
1083 | struct socks_state *sxstate,
|
---|
1084 | struct Curl_easy *data)
|
---|
1085 | {
|
---|
1086 | CURLcode result = CURLE_OK;
|
---|
1087 | CURLproxycode pxresult = CURLPX_OK;
|
---|
1088 | struct connectdata *conn = cf->conn;
|
---|
1089 |
|
---|
1090 | switch(conn->socks_proxy.proxytype) {
|
---|
1091 | case CURLPROXY_SOCKS5:
|
---|
1092 | case CURLPROXY_SOCKS5_HOSTNAME:
|
---|
1093 | pxresult = do_SOCKS5(cf, sxstate, data);
|
---|
1094 | break;
|
---|
1095 |
|
---|
1096 | case CURLPROXY_SOCKS4:
|
---|
1097 | case CURLPROXY_SOCKS4A:
|
---|
1098 | pxresult = do_SOCKS4(cf, sxstate, data);
|
---|
1099 | break;
|
---|
1100 |
|
---|
1101 | default:
|
---|
1102 | failf(data, "unknown proxytype option given");
|
---|
1103 | result = CURLE_COULDNT_CONNECT;
|
---|
1104 | } /* switch proxytype */
|
---|
1105 | if(pxresult) {
|
---|
1106 | result = CURLE_PROXY;
|
---|
1107 | data->info.pxcode = pxresult;
|
---|
1108 | }
|
---|
1109 |
|
---|
1110 | return result;
|
---|
1111 | }
|
---|
1112 |
|
---|
1113 | static void socks_proxy_cf_free(struct Curl_cfilter *cf)
|
---|
1114 | {
|
---|
1115 | struct socks_state *sxstate = cf->ctx;
|
---|
1116 | if(sxstate) {
|
---|
1117 | free(sxstate);
|
---|
1118 | cf->ctx = NULL;
|
---|
1119 | }
|
---|
1120 | }
|
---|
1121 |
|
---|
1122 | /* After a TCP connection to the proxy has been verified, this function does
|
---|
1123 | the next magic steps. If 'done' isn't set TRUE, it is not done yet and
|
---|
1124 | must be called again.
|
---|
1125 |
|
---|
1126 | Note: this function's sub-functions call failf()
|
---|
1127 |
|
---|
1128 | */
|
---|
1129 | static CURLcode socks_proxy_cf_connect(struct Curl_cfilter *cf,
|
---|
1130 | struct Curl_easy *data,
|
---|
1131 | bool blocking, bool *done)
|
---|
1132 | {
|
---|
1133 | CURLcode result;
|
---|
1134 | struct connectdata *conn = cf->conn;
|
---|
1135 | int sockindex = cf->sockindex;
|
---|
1136 | struct socks_state *sx = cf->ctx;
|
---|
1137 |
|
---|
1138 | if(cf->connected) {
|
---|
1139 | *done = TRUE;
|
---|
1140 | return CURLE_OK;
|
---|
1141 | }
|
---|
1142 |
|
---|
1143 | result = cf->next->cft->do_connect(cf->next, data, blocking, done);
|
---|
1144 | if(result || !*done)
|
---|
1145 | return result;
|
---|
1146 |
|
---|
1147 | if(!sx) {
|
---|
1148 | sx = calloc(1, sizeof(*sx));
|
---|
1149 | if(!sx)
|
---|
1150 | return CURLE_OUT_OF_MEMORY;
|
---|
1151 | cf->ctx = sx;
|
---|
1152 | }
|
---|
1153 |
|
---|
1154 | if(sx->state == CONNECT_INIT) {
|
---|
1155 | /* for the secondary socket (FTP), use the "connect to host"
|
---|
1156 | * but ignore the "connect to port" (use the secondary port)
|
---|
1157 | */
|
---|
1158 | sxstate(sx, data, CONNECT_SOCKS_INIT);
|
---|
1159 | sx->hostname =
|
---|
1160 | conn->bits.httpproxy ?
|
---|
1161 | conn->http_proxy.host.name :
|
---|
1162 | conn->bits.conn_to_host ?
|
---|
1163 | conn->conn_to_host.name :
|
---|
1164 | sockindex == SECONDARYSOCKET ?
|
---|
1165 | conn->secondaryhostname : conn->host.name;
|
---|
1166 | sx->remote_port =
|
---|
1167 | conn->bits.httpproxy ? (int)conn->http_proxy.port :
|
---|
1168 | sockindex == SECONDARYSOCKET ? conn->secondary_port :
|
---|
1169 | conn->bits.conn_to_port ? conn->conn_to_port :
|
---|
1170 | conn->remote_port;
|
---|
1171 | sx->proxy_user = conn->socks_proxy.user;
|
---|
1172 | sx->proxy_password = conn->socks_proxy.passwd;
|
---|
1173 | }
|
---|
1174 |
|
---|
1175 | result = connect_SOCKS(cf, sx, data);
|
---|
1176 | if(!result && sx->state == CONNECT_DONE) {
|
---|
1177 | cf->connected = TRUE;
|
---|
1178 | Curl_verboseconnect(data, conn, cf->sockindex);
|
---|
1179 | socks_proxy_cf_free(cf);
|
---|
1180 | }
|
---|
1181 |
|
---|
1182 | *done = cf->connected;
|
---|
1183 | return result;
|
---|
1184 | }
|
---|
1185 |
|
---|
1186 | static void socks_cf_adjust_pollset(struct Curl_cfilter *cf,
|
---|
1187 | struct Curl_easy *data,
|
---|
1188 | struct easy_pollset *ps)
|
---|
1189 | {
|
---|
1190 | struct socks_state *sx = cf->ctx;
|
---|
1191 |
|
---|
1192 | if(!cf->connected && sx) {
|
---|
1193 | /* If we are not connected, the filter below is and has nothing
|
---|
1194 | * to wait on, we determine what to wait for. */
|
---|
1195 | curl_socket_t sock = Curl_conn_cf_get_socket(cf, data);
|
---|
1196 | switch(sx->state) {
|
---|
1197 | case CONNECT_RESOLVING:
|
---|
1198 | case CONNECT_SOCKS_READ:
|
---|
1199 | case CONNECT_AUTH_READ:
|
---|
1200 | case CONNECT_REQ_READ:
|
---|
1201 | case CONNECT_REQ_READ_MORE:
|
---|
1202 | Curl_pollset_set_in_only(data, ps, sock);
|
---|
1203 | break;
|
---|
1204 | default:
|
---|
1205 | Curl_pollset_set_out_only(data, ps, sock);
|
---|
1206 | break;
|
---|
1207 | }
|
---|
1208 | }
|
---|
1209 | }
|
---|
1210 |
|
---|
1211 | static void socks_proxy_cf_close(struct Curl_cfilter *cf,
|
---|
1212 | struct Curl_easy *data)
|
---|
1213 | {
|
---|
1214 |
|
---|
1215 | DEBUGASSERT(cf->next);
|
---|
1216 | cf->connected = FALSE;
|
---|
1217 | socks_proxy_cf_free(cf);
|
---|
1218 | cf->next->cft->do_close(cf->next, data);
|
---|
1219 | }
|
---|
1220 |
|
---|
1221 | static void socks_proxy_cf_destroy(struct Curl_cfilter *cf,
|
---|
1222 | struct Curl_easy *data)
|
---|
1223 | {
|
---|
1224 | (void)data;
|
---|
1225 | socks_proxy_cf_free(cf);
|
---|
1226 | }
|
---|
1227 |
|
---|
1228 | static void socks_cf_get_host(struct Curl_cfilter *cf,
|
---|
1229 | struct Curl_easy *data,
|
---|
1230 | const char **phost,
|
---|
1231 | const char **pdisplay_host,
|
---|
1232 | int *pport)
|
---|
1233 | {
|
---|
1234 | (void)data;
|
---|
1235 | if(!cf->connected) {
|
---|
1236 | *phost = cf->conn->socks_proxy.host.name;
|
---|
1237 | *pdisplay_host = cf->conn->http_proxy.host.dispname;
|
---|
1238 | *pport = (int)cf->conn->socks_proxy.port;
|
---|
1239 | }
|
---|
1240 | else {
|
---|
1241 | cf->next->cft->get_host(cf->next, data, phost, pdisplay_host, pport);
|
---|
1242 | }
|
---|
1243 | }
|
---|
1244 |
|
---|
1245 | struct Curl_cftype Curl_cft_socks_proxy = {
|
---|
1246 | "SOCKS-PROXYY",
|
---|
1247 | CF_TYPE_IP_CONNECT,
|
---|
1248 | 0,
|
---|
1249 | socks_proxy_cf_destroy,
|
---|
1250 | socks_proxy_cf_connect,
|
---|
1251 | socks_proxy_cf_close,
|
---|
1252 | socks_cf_get_host,
|
---|
1253 | socks_cf_adjust_pollset,
|
---|
1254 | Curl_cf_def_data_pending,
|
---|
1255 | Curl_cf_def_send,
|
---|
1256 | Curl_cf_def_recv,
|
---|
1257 | Curl_cf_def_cntrl,
|
---|
1258 | Curl_cf_def_conn_is_alive,
|
---|
1259 | Curl_cf_def_conn_keep_alive,
|
---|
1260 | Curl_cf_def_query,
|
---|
1261 | };
|
---|
1262 |
|
---|
1263 | CURLcode Curl_cf_socks_proxy_insert_after(struct Curl_cfilter *cf_at,
|
---|
1264 | struct Curl_easy *data)
|
---|
1265 | {
|
---|
1266 | struct Curl_cfilter *cf;
|
---|
1267 | CURLcode result;
|
---|
1268 |
|
---|
1269 | (void)data;
|
---|
1270 | result = Curl_cf_create(&cf, &Curl_cft_socks_proxy, NULL);
|
---|
1271 | if(!result)
|
---|
1272 | Curl_conn_cf_insert_after(cf_at, cf);
|
---|
1273 | return result;
|
---|
1274 | }
|
---|
1275 |
|
---|
1276 | #endif /* CURL_DISABLE_PROXY */
|
---|