1/***************************************************************************
2 * _ _ ____ _
3 * Project ___| | | | _ \| |
4 * / __| | | | |_) | |
5 * | (__| |_| | _ <| |___
6 * \___|\___/|_| \_\_____|
7 *
8 * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@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(USE_WINDOWS_SSPI) && 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 "warnless.h"
35#include "curl_multibyte.h"
36#include "sendf.h"
37#include "strerror.h"
38
39/* The last #include files should be: */
40#include "curl_memory.h"
41#include "memdebug.h"
42
43/*
44 * Curl_auth_is_spnego_supported()
45 *
46 * This is used to evaluate if SPNEGO (Negotiate) is supported.
47 *
48 * Parameters: None
49 *
50 * Returns TRUE if Negotiate is supported by Windows SSPI.
51 */
52bool Curl_auth_is_spnego_supported(void)
53{
54 PSecPkgInfo SecurityPackage;
55 SECURITY_STATUS status;
56
57 /* Query the security package for Negotiate */
58 status = s_pSecFn->QuerySecurityPackageInfo((TCHAR *)
59 TEXT(SP_NAME_NEGOTIATE),
60 &SecurityPackage);
61
62 /* Release the package buffer as it is not required anymore */
63 if(status == SEC_E_OK) {
64 s_pSecFn->FreeContextBuffer(SecurityPackage);
65 }
66
67
68 return (status == SEC_E_OK ? TRUE : FALSE);
69}
70
71/*
72 * Curl_auth_decode_spnego_message()
73 *
74 * This is used to decode an already encoded SPNEGO (Negotiate) challenge
75 * message.
76 *
77 * Parameters:
78 *
79 * data [in] - The session handle.
80 * user [in] - The user name in the format User or Domain\User.
81 * password [in] - The user's password.
82 * service [in] - The service type such as http, smtp, pop or imap.
83 * host [in] - The host name.
84 * chlg64 [in] - The optional base64 encoded challenge message.
85 * nego [in/out] - The Negotiate data struct being used and modified.
86 *
87 * Returns CURLE_OK on success.
88 */
89CURLcode Curl_auth_decode_spnego_message(struct Curl_easy *data,
90 const char *user,
91 const char *password,
92 const char *service,
93 const char *host,
94 const char *chlg64,
95 struct negotiatedata *nego)
96{
97 CURLcode result = CURLE_OK;
98 size_t chlglen = 0;
99 unsigned char *chlg = NULL;
100 PSecPkgInfo SecurityPackage;
101 SecBuffer chlg_buf[2];
102 SecBuffer resp_buf;
103 SecBufferDesc chlg_desc;
104 SecBufferDesc resp_desc;
105 unsigned long attrs;
106 TimeStamp expiry; /* For Windows 9x compatibility of SSPI calls */
107
108#if defined(CURL_DISABLE_VERBOSE_STRINGS)
109 (void) data;
110#endif
111
112 if(nego->context && nego->status == SEC_E_OK) {
113 /* We finished successfully our part of authentication, but server
114 * rejected it (since we're again here). Exit with an error since we
115 * can't invent anything better */
116 Curl_auth_cleanup_spnego(nego);
117 return CURLE_LOGIN_DENIED;
118 }
119
120 if(!nego->spn) {
121 /* Generate our SPN */
122 nego->spn = Curl_auth_build_spn(service, host, NULL);
123 if(!nego->spn)
124 return CURLE_OUT_OF_MEMORY;
125 }
126
127 if(!nego->output_token) {
128 /* Query the security package for Negotiate */
129 nego->status = s_pSecFn->QuerySecurityPackageInfo((TCHAR *)
130 TEXT(SP_NAME_NEGOTIATE),
131 &SecurityPackage);
132 if(nego->status != SEC_E_OK)
133 return CURLE_NOT_BUILT_IN;
134
135 nego->token_max = SecurityPackage->cbMaxToken;
136
137 /* Release the package buffer as it is not required anymore */
138 s_pSecFn->FreeContextBuffer(SecurityPackage);
139
140 /* Allocate our output buffer */
141 nego->output_token = malloc(nego->token_max);
142 if(!nego->output_token)
143 return CURLE_OUT_OF_MEMORY;
144 }
145
146 if(!nego->credentials) {
147 /* Do we have credentials to use or are we using single sign-on? */
148 if(user && *user) {
149 /* Populate our identity structure */
150 result = Curl_create_sspi_identity(user, password, &nego->identity);
151 if(result)
152 return result;
153
154 /* Allow proper cleanup of the identity structure */
155 nego->p_identity = &nego->identity;
156 }
157 else
158 /* Use the current Windows user */
159 nego->p_identity = NULL;
160
161 /* Allocate our credentials handle */
162 nego->credentials = calloc(1, sizeof(CredHandle));
163 if(!nego->credentials)
164 return CURLE_OUT_OF_MEMORY;
165
166 /* Acquire our credentials handle */
167 nego->status =
168 s_pSecFn->AcquireCredentialsHandle(NULL,
169 (TCHAR *)TEXT(SP_NAME_NEGOTIATE),
170 SECPKG_CRED_OUTBOUND, NULL,
171 nego->p_identity, NULL, NULL,
172 nego->credentials, &expiry);
173 if(nego->status != SEC_E_OK)
174 return CURLE_AUTH_ERROR;
175
176 /* Allocate our new context handle */
177 nego->context = calloc(1, sizeof(CtxtHandle));
178 if(!nego->context)
179 return CURLE_OUT_OF_MEMORY;
180 }
181
182 if(chlg64 && *chlg64) {
183 /* Decode the base-64 encoded challenge message */
184 if(*chlg64 != '=') {
185 result = Curl_base64_decode(chlg64, &chlg, &chlglen);
186 if(result)
187 return result;
188 }
189
190 /* Ensure we have a valid challenge message */
191 if(!chlg) {
192 infof(data, "SPNEGO handshake failure (empty challenge message)\n");
193
194 return CURLE_BAD_CONTENT_ENCODING;
195 }
196
197 /* Setup the challenge "input" security buffer */
198 chlg_desc.ulVersion = SECBUFFER_VERSION;
199 chlg_desc.cBuffers = 1;
200 chlg_desc.pBuffers = &chlg_buf[0];
201 chlg_buf[0].BufferType = SECBUFFER_TOKEN;
202 chlg_buf[0].pvBuffer = chlg;
203 chlg_buf[0].cbBuffer = curlx_uztoul(chlglen);
204
205#ifdef SECPKG_ATTR_ENDPOINT_BINDINGS
206 /* ssl context comes from Schannel.
207 * When extended protection is used in IIS server,
208 * we have to pass a second SecBuffer to the SecBufferDesc
209 * otherwise IIS will not pass the authentication (401 response).
210 * Minimum supported version is Windows 7.
211 * https://docs.microsoft.com/en-us/security-updates
212 * /SecurityAdvisories/2009/973811
213 */
214 if(nego->sslContext) {
215 SEC_CHANNEL_BINDINGS channelBindings;
216 SecPkgContext_Bindings pkgBindings;
217 pkgBindings.Bindings = &channelBindings;
218 nego->status = s_pSecFn->QueryContextAttributes(
219 nego->sslContext,
220 SECPKG_ATTR_ENDPOINT_BINDINGS,
221 &pkgBindings
222 );
223 if(nego->status == SEC_E_OK) {
224 chlg_desc.cBuffers++;
225 chlg_buf[1].BufferType = SECBUFFER_CHANNEL_BINDINGS;
226 chlg_buf[1].cbBuffer = pkgBindings.BindingsLength;
227 chlg_buf[1].pvBuffer = pkgBindings.Bindings;
228 }
229 }
230#endif
231 }
232
233 /* Setup the response "output" security buffer */
234 resp_desc.ulVersion = SECBUFFER_VERSION;
235 resp_desc.cBuffers = 1;
236 resp_desc.pBuffers = &resp_buf;
237 resp_buf.BufferType = SECBUFFER_TOKEN;
238 resp_buf.pvBuffer = nego->output_token;
239 resp_buf.cbBuffer = curlx_uztoul(nego->token_max);
240
241 /* Generate our challenge-response message */
242 nego->status = s_pSecFn->InitializeSecurityContext(nego->credentials,
243 chlg ? nego->context :
244 NULL,
245 nego->spn,
246 ISC_REQ_CONFIDENTIALITY,
247 0, SECURITY_NATIVE_DREP,
248 chlg ? &chlg_desc : NULL,
249 0, nego->context,
250 &resp_desc, &attrs,
251 &expiry);
252
253 /* Free the decoded challenge as it is not required anymore */
254 free(chlg);
255
256 if(GSS_ERROR(nego->status)) {
257 char buffer[STRERROR_LEN];
258 failf(data, "InitializeSecurityContext failed: %s",
259 Curl_sspi_strerror(nego->status, buffer, sizeof(buffer)));
260
261 if(nego->status == (DWORD)SEC_E_INSUFFICIENT_MEMORY)
262 return CURLE_OUT_OF_MEMORY;
263
264 return CURLE_AUTH_ERROR;
265 }
266
267 if(nego->status == SEC_I_COMPLETE_NEEDED ||
268 nego->status == SEC_I_COMPLETE_AND_CONTINUE) {
269 nego->status = s_pSecFn->CompleteAuthToken(nego->context, &resp_desc);
270 if(GSS_ERROR(nego->status)) {
271 char buffer[STRERROR_LEN];
272 failf(data, "CompleteAuthToken failed: %s",
273 Curl_sspi_strerror(nego->status, buffer, sizeof(buffer)));
274
275 if(nego->status == (DWORD)SEC_E_INSUFFICIENT_MEMORY)
276 return CURLE_OUT_OF_MEMORY;
277
278 return CURLE_AUTH_ERROR;
279 }
280 }
281
282 nego->output_token_length = resp_buf.cbBuffer;
283
284 return result;
285}
286
287/*
288 * Curl_auth_create_spnego_message()
289 *
290 * This is used to generate an already encoded SPNEGO (Negotiate) response
291 * message ready for sending to the recipient.
292 *
293 * Parameters:
294 *
295 * data [in] - The session handle.
296 * nego [in/out] - The Negotiate data struct being used and modified.
297 * outptr [in/out] - The address where a pointer to newly allocated memory
298 * holding the result will be stored upon completion.
299 * outlen [out] - The length of the output message.
300 *
301 * Returns CURLE_OK on success.
302 */
303CURLcode Curl_auth_create_spnego_message(struct Curl_easy *data,
304 struct negotiatedata *nego,
305 char **outptr, size_t *outlen)
306{
307 CURLcode result;
308
309 /* Base64 encode the already generated response */
310 result = Curl_base64_encode(data,
311 (const char *) nego->output_token,
312 nego->output_token_length,
313 outptr, outlen);
314
315 if(result)
316 return result;
317
318 if(!*outptr || !*outlen) {
319 free(*outptr);
320 return CURLE_REMOTE_ACCESS_DENIED;
321 }
322
323 return CURLE_OK;
324}
325
326/*
327 * Curl_auth_cleanup_spnego()
328 *
329 * This is used to clean up the SPNEGO (Negotiate) specific data.
330 *
331 * Parameters:
332 *
333 * nego [in/out] - The Negotiate data struct being cleaned up.
334 *
335 */
336void Curl_auth_cleanup_spnego(struct negotiatedata *nego)
337{
338 /* Free our security context */
339 if(nego->context) {
340 s_pSecFn->DeleteSecurityContext(nego->context);
341 free(nego->context);
342 nego->context = NULL;
343 }
344
345 /* Free our credentials handle */
346 if(nego->credentials) {
347 s_pSecFn->FreeCredentialsHandle(nego->credentials);
348 free(nego->credentials);
349 nego->credentials = NULL;
350 }
351
352 /* Free our identity */
353 Curl_sspi_free_identity(nego->p_identity);
354 nego->p_identity = NULL;
355
356 /* Free the SPN and output token */
357 Curl_safefree(nego->spn);
358 Curl_safefree(nego->output_token);
359
360 /* Reset any variables */
361 nego->status = 0;
362 nego->token_max = 0;
363 nego->noauthpersist = FALSE;
364 nego->havenoauthpersist = FALSE;
365 nego->havenegdata = FALSE;
366 nego->havemultiplerequests = FALSE;
367}
368
369#endif /* USE_WINDOWS_SSPI && USE_SPNEGO */
370