1 /*************************************************************************** 2 * _ _ ____ _ 3 * Project ___| | | | _ \| | 4 * / __| | | | |_) | | 5 * | (__| |_| | _ <| |___ 6 * \___|\___/|_| \_\_____| 7 * 8 * Copyright (C) 1998 - 2016, Daniel Stenberg, <daniel (at) haxx.se>, et al. 9 * 10 * This software is licensed as described in the file COPYING, which 11 * you should have received as part of this distribution. The terms 12 * are also available at https://curl.haxx.se/docs/copyright.html. 13 * 14 * You may opt to use, copy, modify, merge, publish, distribute and/or sell 15 * copies of the Software, and permit persons to whom the Software is 16 * furnished to do so, under the terms of the COPYING file. 17 * 18 * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY 19 * KIND, either express or implied. 20 * 21 * RFC4178 Simple and Protected GSS-API Negotiation Mechanism 22 * 23 ***************************************************************************/ 24 25 #include "curl_setup.h" 26 27 #if defined(HAVE_GSSAPI) && defined(USE_SPNEGO) 28 29 #include <curl/curl.h> 30 31 #include "vauth/vauth.h" 32 #include "urldata.h" 33 #include "curl_base64.h" 34 #include "curl_gssapi.h" 35 #include "warnless.h" 36 #include "curl_multibyte.h" 37 #include "sendf.h" 38 39 /* The last #include files should be: */ 40 #include "curl_memory.h" 41 #include "memdebug.h" 42 43 /* 44 * Curl_auth_decode_spnego_message() 45 * 46 * This is used to decode an already encoded SPNEGO (Negotiate) challenge 47 * message. 48 * 49 * Parameters: 50 * 51 * data [in] - The session handle. 52 * userp [in] - The user name in the format User or Domain\User. 53 * passdwp [in] - The user's password. 54 * service [in] - The service type such as http, smtp, pop or imap. 55 * host [in] - The host name. 56 * chlg64 [in] - The optional base64 encoded challenge message. 57 * nego [in/out] - The Negotiate data struct being used and modified. 58 * 59 * Returns CURLE_OK on success. 60 */ 61 CURLcode Curl_auth_decode_spnego_message(struct Curl_easy *data, 62 const char *user, 63 const char *password, 64 const char *service, 65 const char *host, 66 const char *chlg64, 67 struct negotiatedata *nego) 68 { 69 CURLcode result = CURLE_OK; 70 size_t chlglen = 0; 71 unsigned char *chlg = NULL; 72 OM_uint32 major_status; 73 OM_uint32 minor_status; 74 OM_uint32 unused_status; 75 gss_buffer_desc spn_token = GSS_C_EMPTY_BUFFER; 76 gss_buffer_desc input_token = GSS_C_EMPTY_BUFFER; 77 gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER; 78 79 (void) user; 80 (void) password; 81 82 if(nego->context && nego->status == GSS_S_COMPLETE) { 83 /* We finished successfully our part of authentication, but server 84 * rejected it (since we're again here). Exit with an error since we 85 * can't invent anything better */ 86 Curl_auth_spnego_cleanup(nego); 87 return CURLE_LOGIN_DENIED; 88 } 89 90 if(!nego->spn) { 91 /* Generate our SPN */ 92 char *spn = Curl_auth_build_spn(service, NULL, host); 93 if(!spn) 94 return CURLE_OUT_OF_MEMORY; 95 96 /* Populate the SPN structure */ 97 spn_token.value = spn; 98 spn_token.length = strlen(spn); 99 100 /* Import the SPN */ 101 major_status = gss_import_name(&minor_status, &spn_token, 102 GSS_C_NT_HOSTBASED_SERVICE, 103 &nego->spn); 104 if(GSS_ERROR(major_status)) { 105 Curl_gss_log_error(data, "gss_import_name() failed: ", 106 major_status, minor_status); 107 108 free(spn); 109 110 return CURLE_OUT_OF_MEMORY; 111 } 112 113 free(spn); 114 } 115 116 if(chlg64 && *chlg64) { 117 /* Decode the base-64 encoded challenge message */ 118 if(*chlg64 != '=') { 119 result = Curl_base64_decode(chlg64, &chlg, &chlglen); 120 if(result) 121 return result; 122 } 123 124 /* Ensure we have a valid challenge message */ 125 if(!chlg) { 126 infof(data, "SPNEGO handshake failure (empty challenge message)\n"); 127 128 return CURLE_BAD_CONTENT_ENCODING; 129 } 130 131 /* Setup the challenge "input" security buffer */ 132 input_token.value = chlg; 133 input_token.length = chlglen; 134 } 135 136 /* Generate our challenge-response message */ 137 major_status = Curl_gss_init_sec_context(data, 138 &minor_status, 139 &nego->context, 140 nego->spn, 141 &Curl_spnego_mech_oid, 142 GSS_C_NO_CHANNEL_BINDINGS, 143 &input_token, 144 &output_token, 145 TRUE, 146 NULL); 147 148 /* Free the decoded challenge as it is not required anymore */ 149 Curl_safefree(input_token.value); 150 151 nego->status = major_status; 152 if(GSS_ERROR(major_status)) { 153 if(output_token.value) 154 gss_release_buffer(&unused_status, &output_token); 155 156 Curl_gss_log_error(data, "gss_init_sec_context() failed: ", 157 major_status, minor_status); 158 159 return CURLE_OUT_OF_MEMORY; 160 } 161 162 if(!output_token.value || !output_token.length) { 163 if(output_token.value) 164 gss_release_buffer(&unused_status, &output_token); 165 166 return CURLE_OUT_OF_MEMORY; 167 } 168 169 nego->output_token = output_token; 170 171 return CURLE_OK; 172 } 173 174 /* 175 * Curl_auth_create_spnego_message() 176 * 177 * This is used to generate an already encoded SPNEGO (Negotiate) response 178 * message ready for sending to the recipient. 179 * 180 * Parameters: 181 * 182 * data [in] - The session handle. 183 * nego [in/out] - The Negotiate data struct being used and modified. 184 * outptr [in/out] - The address where a pointer to newly allocated memory 185 * holding the result will be stored upon completion. 186 * outlen [out] - The length of the output message. 187 * 188 * Returns CURLE_OK on success. 189 */ 190 CURLcode Curl_auth_create_spnego_message(struct Curl_easy *data, 191 struct negotiatedata *nego, 192 char **outptr, size_t *outlen) 193 { 194 CURLcode result; 195 OM_uint32 minor_status; 196 197 /* Base64 encode the already generated response */ 198 result = Curl_base64_encode(data, 199 nego->output_token.value, 200 nego->output_token.length, 201 outptr, outlen); 202 203 if(result) { 204 gss_release_buffer(&minor_status, &nego->output_token); 205 nego->output_token.value = NULL; 206 nego->output_token.length = 0; 207 208 return result; 209 } 210 211 if(!*outptr || !*outlen) { 212 gss_release_buffer(&minor_status, &nego->output_token); 213 nego->output_token.value = NULL; 214 nego->output_token.length = 0; 215 216 return CURLE_REMOTE_ACCESS_DENIED; 217 } 218 219 return CURLE_OK; 220 } 221 222 /* 223 * Curl_auth_spnego_cleanup() 224 * 225 * This is used to clean up the SPNEGO (Negotiate) specific data. 226 * 227 * Parameters: 228 * 229 * nego [in/out] - The Negotiate data struct being cleaned up. 230 * 231 */ 232 void Curl_auth_spnego_cleanup(struct negotiatedata *nego) 233 { 234 OM_uint32 minor_status; 235 236 /* Free our security context */ 237 if(nego->context != GSS_C_NO_CONTEXT) { 238 gss_delete_sec_context(&minor_status, &nego->context, GSS_C_NO_BUFFER); 239 nego->context = GSS_C_NO_CONTEXT; 240 } 241 242 /* Free the output token */ 243 if(nego->output_token.value) { 244 gss_release_buffer(&minor_status, &nego->output_token); 245 nego->output_token.value = NULL; 246 nego->output_token.length = 0; 247 248 } 249 250 /* Free the SPN */ 251 if(nego->spn != GSS_C_NO_NAME) { 252 gss_release_name(&minor_status, &nego->spn); 253 nego->spn = GSS_C_NO_NAME; 254 } 255 256 /* Reset any variables */ 257 nego->status = 0; 258 } 259 260 #endif /* HAVE_GSSAPI && USE_SPNEGO */ 261