/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 1998 - 2021, Daniel Stenberg, , 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.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(HAVE_GSSAPI) && defined(USE_SPNEGO) #include #include "vauth/vauth.h" #include "urldata.h" #include "curl_base64.h" #include "curl_gssapi.h" #include "warnless.h" #include "curl_multibyte.h" #include "sendf.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 supported by the GSS-API library. */ bool Curl_auth_is_spnego_supported(void) { return TRUE; } /* * Curl_auth_decode_spnego_message() * * This is used to decode an already encoded SPNEGO (Negotiate) challenge * message. * * Parameters: * * data [in] - The session handle. * userp [in] - The user name in the format User or Domain\User. * passwdp [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; OM_uint32 major_status; OM_uint32 minor_status; OM_uint32 unused_status; gss_buffer_desc spn_token = GSS_C_EMPTY_BUFFER; gss_buffer_desc input_token = GSS_C_EMPTY_BUFFER; gss_buffer_desc output_token = GSS_C_EMPTY_BUFFER; (void) user; (void) password; if(nego->context && nego->status == GSS_S_COMPLETE) { /* 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 */ char *spn = Curl_auth_build_spn(service, NULL, host); if(!spn) return CURLE_OUT_OF_MEMORY; /* Populate the SPN structure */ spn_token.value = spn; spn_token.length = strlen(spn); /* Import the SPN */ major_status = gss_import_name(&minor_status, &spn_token, GSS_C_NT_HOSTBASED_SERVICE, &nego->spn); if(GSS_ERROR(major_status)) { Curl_gss_log_error(data, "gss_import_name() failed: ", major_status, minor_status); free(spn); return CURLE_AUTH_ERROR; } free(spn); } 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)"); return CURLE_BAD_CONTENT_ENCODING; } /* Setup the challenge "input" security buffer */ input_token.value = chlg; input_token.length = chlglen; } /* Generate our challenge-response message */ major_status = Curl_gss_init_sec_context(data, &minor_status, &nego->context, nego->spn, &Curl_spnego_mech_oid, GSS_C_NO_CHANNEL_BINDINGS, &input_token, &output_token, TRUE, NULL); /* Free the decoded challenge as it is not required anymore */ Curl_safefree(input_token.value); nego->status = major_status; if(GSS_ERROR(major_status)) { if(output_token.value) gss_release_buffer(&unused_status, &output_token); Curl_gss_log_error(data, "gss_init_sec_context() failed: ", major_status, minor_status); return CURLE_AUTH_ERROR; } if(!output_token.value || !output_token.length) { if(output_token.value) gss_release_buffer(&unused_status, &output_token); return CURLE_AUTH_ERROR; } /* Free previous token */ if(nego->output_token.length && nego->output_token.value) gss_release_buffer(&unused_status, &nego->output_token); nego->output_token = output_token; return CURLE_OK; } /* * 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; OM_uint32 minor_status; /* Base64 encode the already generated response */ result = Curl_base64_encode(data, nego->output_token.value, nego->output_token.length, outptr, outlen); if(result) { gss_release_buffer(&minor_status, &nego->output_token); nego->output_token.value = NULL; nego->output_token.length = 0; return result; } if(!*outptr || !*outlen) { gss_release_buffer(&minor_status, &nego->output_token); nego->output_token.value = NULL; nego->output_token.length = 0; 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) { OM_uint32 minor_status; /* Free our security context */ if(nego->context != GSS_C_NO_CONTEXT) { gss_delete_sec_context(&minor_status, &nego->context, GSS_C_NO_BUFFER); nego->context = GSS_C_NO_CONTEXT; } /* Free the output token */ if(nego->output_token.value) { gss_release_buffer(&minor_status, &nego->output_token); nego->output_token.value = NULL; nego->output_token.length = 0; } /* Free the SPN */ if(nego->spn != GSS_C_NO_NAME) { gss_release_name(&minor_status, &nego->spn); nego->spn = GSS_C_NO_NAME; } /* Reset any variables */ nego->status = 0; nego->noauthpersist = FALSE; nego->havenoauthpersist = FALSE; nego->havenegdata = FALSE; nego->havemultiplerequests = FALSE; } #endif /* HAVE_GSSAPI && USE_SPNEGO */