/*************************************************************************** * _ _ ____ _ * Project ___| | | | _ \| | * / __| | | | |_) | | * | (__| |_| | _ <| |___ * \___|\___/|_| \_\_____| * * Copyright (C) 2014, Steve Holme, . * * 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 http://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. * * RFC4752 The Kerberos V5 ("GSSAPI") SASL Mechanism * ***************************************************************************/ #include "curl_setup.h" #if defined(HAVE_GSSAPI) && defined(USE_KERBEROS5) #ifdef HAVE_OLD_GSSMIT #define GSS_C_NT_HOSTBASED_SERVICE gss_nt_service_name #define NCOMPAT 1 #endif #include #include "curl_sasl.h" #include "urldata.h" #include "curl_base64.h" #include "curl_gssapi.h" #include "curl_memory.h" #define _MPRINTF_REPLACE /* use our functions only */ #include /* The last #include file should be: */ #include "memdebug.h" /* * Curl_sasl_build_gssapi_spn() * * This is used to build a SPN string in the format service@host. * * Parameters: * * serivce [in] - The service type such as www, smtp, pop or imap. * host [in] - The host name or realm. * * Returns a pointer to the newly allocated SPN. */ static char *Curl_sasl_build_gssapi_spn(const char *service, const char *host) { /* Generate and return our SPN */ return aprintf("%s@%s", service, host); } /* * Curl_sasl_create_gssapi_user_message() * * This is used to generate an already encoded GSSAPI (Kerberos V5) user token * message ready for sending to the recipient. * * Parameters: * * data [in] - The session handle. * userp [in] - The user name. * passdwp [in] - The user's password. * service [in] - The service type such as www, smtp, pop or imap. * mutual_auth [in] - Flag specifing whether or not mutual authentication * is enabled. * chlg64 [in] - Pointer to the optional base64 encoded challenge * message. * krb5 [in/out] - The gssapi 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_sasl_create_gssapi_user_message(struct SessionHandle *data, const char *userp, const char *passwdp, const char *service, const bool mutual_auth, const char *chlg64, struct kerberos5data *krb5, char **outptr, size_t *outlen) { CURLcode result = CURLE_OK; size_t chlglen = 0; unsigned char *chlg = NULL; OM_uint32 gss_status; OM_uint32 gss_major_status; OM_uint32 gss_minor_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) userp; (void) passwdp; (void) mutual_auth; if(krb5->context == GSS_C_NO_CONTEXT) { /* Generate our SPN */ char *spn = Curl_sasl_build_gssapi_spn(service, data->easy_conn->host.name); if(!spn) return CURLE_OUT_OF_MEMORY; /* Populate the SPN structure */ spn_token.value = spn; spn_token.length = strlen(spn); /* Import the SPN */ gss_major_status = gss_import_name(&gss_minor_status, &spn_token, gss_nt_service_name, &krb5->spn); if(GSS_ERROR(gss_major_status)) { Curl_gss_log_error(data, gss_minor_status, "gss_import_name() failed: "); return CURLE_OUT_OF_MEMORY; } } else { /* Decode the base-64 encoded challenge message */ if(strlen(chlg64) && *chlg64 != '=') { result = Curl_base64_decode(chlg64, &chlg, &chlglen); if(result) return result; } /* Ensure we have a valid challenge message */ if(!chlg) return CURLE_BAD_CONTENT_ENCODING; /* Setup the challenge "input" security buffer */ input_token.value = chlg; input_token.length = chlglen; } gss_major_status = Curl_gss_init_sec_context(data, &gss_minor_status, &krb5->context, krb5->spn, &Curl_krb5_mech_oid, GSS_C_NO_CHANNEL_BINDINGS, &input_token, &output_token, NULL); Curl_safefree(input_token.value); if(GSS_ERROR(gss_major_status)) { if(output_token.value) gss_release_buffer(&gss_status, &output_token); Curl_gss_log_error(data, gss_minor_status, "gss_init_sec_context() failed: "); return CURLE_RECV_ERROR; } if(output_token.value && output_token.length) { /* Base64 encode the response */ result = Curl_base64_encode(data, (char *) output_token.value, output_token.length, outptr, outlen); gss_release_buffer(&gss_status, &output_token); } return result; } /* * Curl_sasl_create_gssapi_security_message() * * This is used to generate an already encoded GSSAPI (Kerberos V5) security * token message ready for sending to the recipient. * * Parameters: * * data [in] - The session handle. * chlg64 [in] - Pointer to the optional base64 encoded challenge message. * krb5 [in/out] - The gssapi 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_sasl_create_gssapi_security_message(struct SessionHandle *data, const char *chlg64, struct kerberos5data *krb5, char **outptr, size_t *outlen) { (void) data; (void) chlg64; (void) krb5; (void) outptr; (void) outlen; return CURLE_NOT_BUILT_IN; } void Curl_sasl_gssapi_cleanup(struct kerberos5data *krb5) { OM_uint32 minor_status; /* Free our security context */ if(krb5->context != GSS_C_NO_CONTEXT) { gss_delete_sec_context(&minor_status, &krb5->context, GSS_C_NO_BUFFER); krb5->context = GSS_C_NO_CONTEXT; } /* Free the SPN */ if(krb5->spn != GSS_C_NO_NAME) { gss_release_name(&minor_status, &krb5->spn); krb5->spn = GSS_C_NO_NAME; } } #endif /* HAVE_GSSAPI && USE_KERBEROS5 */