--- /dev/null	Thu Jan 01 00:00:00 1970 +0000
+++ b/mupdf-source/thirdparty/curl/lib/vauth/spnego_sspi.c	Mon Sep 15 11:43:07 2025 +0200
@@ -0,0 +1,369 @@
+/***************************************************************************
+ *                                  _   _ ____  _
+ *  Project                     ___| | | |  _ \| |
+ *                             / __| | | | |_) | |
+ *                            | (__| |_| |  _ <| |___
+ *                             \___|\___/|_| \_\_____|
+ *
+ * Copyright (C) 1998 - 2019, Daniel Stenberg, <daniel@haxx.se>, et al.
+ *
+ * This software is licensed as described in the file COPYING, which
+ * you should have received as part of this distribution. The terms
+ * are also available at https://curl.haxx.se/docs/copyright.html.
+ *
+ * You may opt to use, copy, modify, merge, publish, distribute and/or sell
+ * copies of the Software, and permit persons to whom the Software is
+ * furnished to do so, under the terms of the COPYING file.
+ *
+ * This software is distributed on an "AS IS" basis, WITHOUT WARRANTY OF ANY
+ * KIND, either express or implied.
+ *
+ * RFC4178 Simple and Protected GSS-API Negotiation Mechanism
+ *
+ ***************************************************************************/
+
+#include "curl_setup.h"
+
+#if defined(USE_WINDOWS_SSPI) && defined(USE_SPNEGO)
+
+#include <curl/curl.h>
+
+#include "vauth/vauth.h"
+#include "urldata.h"
+#include "curl_base64.h"
+#include "warnless.h"
+#include "curl_multibyte.h"
+#include "sendf.h"
+#include "strerror.h"
+
+/* The last #include files should be: */
+#include "curl_memory.h"
+#include "memdebug.h"
+
+/*
+ * Curl_auth_is_spnego_supported()
+ *
+ * This is used to evaluate if SPNEGO (Negotiate) is supported.
+ *
+ * Parameters: None
+ *
+ * Returns TRUE if Negotiate is supported by Windows SSPI.
+ */
+bool Curl_auth_is_spnego_supported(void)
+{
+  PSecPkgInfo SecurityPackage;
+  SECURITY_STATUS status;
+
+  /* Query the security package for Negotiate */
+  status = s_pSecFn->QuerySecurityPackageInfo((TCHAR *)
+                                              TEXT(SP_NAME_NEGOTIATE),
+                                              &SecurityPackage);
+
+  /* Release the package buffer as it is not required anymore */
+  if(status == SEC_E_OK) {
+    s_pSecFn->FreeContextBuffer(SecurityPackage);
+  }
+
+
+  return (status == SEC_E_OK ? TRUE : FALSE);
+}
+
+/*
+ * Curl_auth_decode_spnego_message()
+ *
+ * This is used to decode an already encoded SPNEGO (Negotiate) challenge
+ * message.
+ *
+ * Parameters:
+ *
+ * data        [in]     - The session handle.
+ * user        [in]     - The user name in the format User or Domain\User.
+ * password    [in]     - The user's password.
+ * service     [in]     - The service type such as http, smtp, pop or imap.
+ * host        [in]     - The host name.
+ * chlg64      [in]     - The optional base64 encoded challenge message.
+ * nego        [in/out] - The Negotiate data struct being used and modified.
+ *
+ * Returns CURLE_OK on success.
+ */
+CURLcode Curl_auth_decode_spnego_message(struct Curl_easy *data,
+                                         const char *user,
+                                         const char *password,
+                                         const char *service,
+                                         const char *host,
+                                         const char *chlg64,
+                                         struct negotiatedata *nego)
+{
+  CURLcode result = CURLE_OK;
+  size_t chlglen = 0;
+  unsigned char *chlg = NULL;
+  PSecPkgInfo SecurityPackage;
+  SecBuffer chlg_buf[2];
+  SecBuffer resp_buf;
+  SecBufferDesc chlg_desc;
+  SecBufferDesc resp_desc;
+  unsigned long attrs;
+  TimeStamp expiry; /* For Windows 9x compatibility of SSPI calls */
+
+#if defined(CURL_DISABLE_VERBOSE_STRINGS)
+  (void) data;
+#endif
+
+  if(nego->context && nego->status == SEC_E_OK) {
+    /* We finished successfully our part of authentication, but server
+     * rejected it (since we're again here). Exit with an error since we
+     * can't invent anything better */
+    Curl_auth_cleanup_spnego(nego);
+    return CURLE_LOGIN_DENIED;
+  }
+
+  if(!nego->spn) {
+    /* Generate our SPN */
+    nego->spn = Curl_auth_build_spn(service, host, NULL);
+    if(!nego->spn)
+      return CURLE_OUT_OF_MEMORY;
+  }
+
+  if(!nego->output_token) {
+    /* Query the security package for Negotiate */
+    nego->status = s_pSecFn->QuerySecurityPackageInfo((TCHAR *)
+                                                      TEXT(SP_NAME_NEGOTIATE),
+                                                      &SecurityPackage);
+    if(nego->status != SEC_E_OK)
+      return CURLE_NOT_BUILT_IN;
+
+    nego->token_max = SecurityPackage->cbMaxToken;
+
+    /* Release the package buffer as it is not required anymore */
+    s_pSecFn->FreeContextBuffer(SecurityPackage);
+
+    /* Allocate our output buffer */
+    nego->output_token = malloc(nego->token_max);
+    if(!nego->output_token)
+      return CURLE_OUT_OF_MEMORY;
+ }
+
+  if(!nego->credentials) {
+    /* Do we have credentials to use or are we using single sign-on? */
+    if(user && *user) {
+      /* Populate our identity structure */
+      result = Curl_create_sspi_identity(user, password, &nego->identity);
+      if(result)
+        return result;
+
+      /* Allow proper cleanup of the identity structure */
+      nego->p_identity = &nego->identity;
+    }
+    else
+      /* Use the current Windows user */
+      nego->p_identity = NULL;
+
+    /* Allocate our credentials handle */
+    nego->credentials = calloc(1, sizeof(CredHandle));
+    if(!nego->credentials)
+      return CURLE_OUT_OF_MEMORY;
+
+    /* Acquire our credentials handle */
+    nego->status =
+      s_pSecFn->AcquireCredentialsHandle(NULL,
+                                         (TCHAR *)TEXT(SP_NAME_NEGOTIATE),
+                                         SECPKG_CRED_OUTBOUND, NULL,
+                                         nego->p_identity, NULL, NULL,
+                                         nego->credentials, &expiry);
+    if(nego->status != SEC_E_OK)
+      return CURLE_AUTH_ERROR;
+
+    /* Allocate our new context handle */
+    nego->context = calloc(1, sizeof(CtxtHandle));
+    if(!nego->context)
+      return CURLE_OUT_OF_MEMORY;
+  }
+
+  if(chlg64 && *chlg64) {
+    /* Decode the base-64 encoded challenge message */
+    if(*chlg64 != '=') {
+      result = Curl_base64_decode(chlg64, &chlg, &chlglen);
+      if(result)
+        return result;
+    }
+
+    /* Ensure we have a valid challenge message */
+    if(!chlg) {
+      infof(data, "SPNEGO handshake failure (empty challenge message)\n");
+
+      return CURLE_BAD_CONTENT_ENCODING;
+    }
+
+    /* Setup the challenge "input" security buffer */
+    chlg_desc.ulVersion    = SECBUFFER_VERSION;
+    chlg_desc.cBuffers     = 1;
+    chlg_desc.pBuffers     = &chlg_buf[0];
+    chlg_buf[0].BufferType = SECBUFFER_TOKEN;
+    chlg_buf[0].pvBuffer   = chlg;
+    chlg_buf[0].cbBuffer   = curlx_uztoul(chlglen);
+
+#ifdef SECPKG_ATTR_ENDPOINT_BINDINGS
+    /* ssl context comes from Schannel.
+    * When extended protection is used in IIS server,
+    * we have to pass a second SecBuffer to the SecBufferDesc
+    * otherwise IIS will not pass the authentication (401 response).
+    * Minimum supported version is Windows 7.
+    * https://docs.microsoft.com/en-us/security-updates
+    * /SecurityAdvisories/2009/973811
+    */
+    if(nego->sslContext) {
+      SEC_CHANNEL_BINDINGS channelBindings;
+      SecPkgContext_Bindings pkgBindings;
+      pkgBindings.Bindings = &channelBindings;
+      nego->status = s_pSecFn->QueryContextAttributes(
+          nego->sslContext,
+          SECPKG_ATTR_ENDPOINT_BINDINGS,
+          &pkgBindings
+      );
+      if(nego->status == SEC_E_OK) {
+        chlg_desc.cBuffers++;
+        chlg_buf[1].BufferType = SECBUFFER_CHANNEL_BINDINGS;
+        chlg_buf[1].cbBuffer   = pkgBindings.BindingsLength;
+        chlg_buf[1].pvBuffer   = pkgBindings.Bindings;
+      }
+    }
+#endif
+  }
+
+  /* Setup the response "output" security buffer */
+  resp_desc.ulVersion = SECBUFFER_VERSION;
+  resp_desc.cBuffers  = 1;
+  resp_desc.pBuffers  = &resp_buf;
+  resp_buf.BufferType = SECBUFFER_TOKEN;
+  resp_buf.pvBuffer   = nego->output_token;
+  resp_buf.cbBuffer   = curlx_uztoul(nego->token_max);
+
+  /* Generate our challenge-response message */
+  nego->status = s_pSecFn->InitializeSecurityContext(nego->credentials,
+                                                     chlg ? nego->context :
+                                                            NULL,
+                                                     nego->spn,
+                                                     ISC_REQ_CONFIDENTIALITY,
+                                                     0, SECURITY_NATIVE_DREP,
+                                                     chlg ? &chlg_desc : NULL,
+                                                     0, nego->context,
+                                                     &resp_desc, &attrs,
+                                                     &expiry);
+
+  /* Free the decoded challenge as it is not required anymore */
+  free(chlg);
+
+  if(GSS_ERROR(nego->status)) {
+    char buffer[STRERROR_LEN];
+    failf(data, "InitializeSecurityContext failed: %s",
+          Curl_sspi_strerror(nego->status, buffer, sizeof(buffer)));
+
+    if(nego->status == (DWORD)SEC_E_INSUFFICIENT_MEMORY)
+      return CURLE_OUT_OF_MEMORY;
+
+    return CURLE_AUTH_ERROR;
+  }
+
+  if(nego->status == SEC_I_COMPLETE_NEEDED ||
+     nego->status == SEC_I_COMPLETE_AND_CONTINUE) {
+    nego->status = s_pSecFn->CompleteAuthToken(nego->context, &resp_desc);
+    if(GSS_ERROR(nego->status)) {
+      char buffer[STRERROR_LEN];
+      failf(data, "CompleteAuthToken failed: %s",
+            Curl_sspi_strerror(nego->status, buffer, sizeof(buffer)));
+
+      if(nego->status == (DWORD)SEC_E_INSUFFICIENT_MEMORY)
+        return CURLE_OUT_OF_MEMORY;
+
+      return CURLE_AUTH_ERROR;
+    }
+  }
+
+  nego->output_token_length = resp_buf.cbBuffer;
+
+  return result;
+}
+
+/*
+ * Curl_auth_create_spnego_message()
+ *
+ * This is used to generate an already encoded SPNEGO (Negotiate) response
+ * message ready for sending to the recipient.
+ *
+ * Parameters:
+ *
+ * data        [in]     - The session handle.
+ * nego        [in/out] - The Negotiate data struct being used and modified.
+ * outptr      [in/out] - The address where a pointer to newly allocated memory
+ *                        holding the result will be stored upon completion.
+ * outlen      [out]    - The length of the output message.
+ *
+ * Returns CURLE_OK on success.
+ */
+CURLcode Curl_auth_create_spnego_message(struct Curl_easy *data,
+                                         struct negotiatedata *nego,
+                                         char **outptr, size_t *outlen)
+{
+  CURLcode result;
+
+  /* Base64 encode the already generated response */
+  result = Curl_base64_encode(data,
+                              (const char *) nego->output_token,
+                              nego->output_token_length,
+                              outptr, outlen);
+
+  if(result)
+    return result;
+
+  if(!*outptr || !*outlen) {
+    free(*outptr);
+    return CURLE_REMOTE_ACCESS_DENIED;
+  }
+
+  return CURLE_OK;
+}
+
+/*
+ * Curl_auth_cleanup_spnego()
+ *
+ * This is used to clean up the SPNEGO (Negotiate) specific data.
+ *
+ * Parameters:
+ *
+ * nego     [in/out] - The Negotiate data struct being cleaned up.
+ *
+ */
+void Curl_auth_cleanup_spnego(struct negotiatedata *nego)
+{
+  /* Free our security context */
+  if(nego->context) {
+    s_pSecFn->DeleteSecurityContext(nego->context);
+    free(nego->context);
+    nego->context = NULL;
+  }
+
+  /* Free our credentials handle */
+  if(nego->credentials) {
+    s_pSecFn->FreeCredentialsHandle(nego->credentials);
+    free(nego->credentials);
+    nego->credentials = NULL;
+  }
+
+  /* Free our identity */
+  Curl_sspi_free_identity(nego->p_identity);
+  nego->p_identity = NULL;
+
+  /* Free the SPN and output token */
+  Curl_safefree(nego->spn);
+  Curl_safefree(nego->output_token);
+
+  /* Reset any variables */
+  nego->status = 0;
+  nego->token_max = 0;
+  nego->noauthpersist = FALSE;
+  nego->havenoauthpersist = FALSE;
+  nego->havenegdata = FALSE;
+  nego->havemultiplerequests = FALSE;
+}
+
+#endif /* USE_WINDOWS_SSPI && USE_SPNEGO */