/*
* 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;
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) {
infof(data, "GSSAPI handshake failure (empty challenge message)\n");
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,
mutual_auth,
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;
}
CURLcode Curl_input_negotiate(struct connectdata *conn, bool proxy,
const char *header)
{
struct SessionHandle *data = conn->data;
struct negotiatedata *neg_ctx = proxy?&data->state.proxyneg:
&data->state.negotiate;
OM_uint32 major_status, minor_status, discard_st;
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;
size_t len;
size_t rawlen = 0;
CURLcode result;
if(neg_ctx->context && neg_ctx->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_cleanup_negotiate(data);
return CURLE_LOGIN_DENIED;
}
if(!neg_ctx->server_name) {
/* Generate our SPN */
char *spn = Curl_sasl_build_gssapi_spn(
proxy ? data->set.str[STRING_PROXY_SERVICE_NAME] :
data->set.str[STRING_SERVICE_NAME],
proxy ? conn->proxy.name : 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 */
major_status = gss_import_name(&minor_status, &spn_token,
GSS_C_NT_HOSTBASED_SERVICE,
&neg_ctx->server_name);
if(GSS_ERROR(major_status)) {
Curl_gss_log_error(data, minor_status, "gss_import_name() failed: ");
free(spn);
return CURLE_OUT_OF_MEMORY;
}
free(spn);
}
header += strlen("Negotiate");
while(*header && ISSPACE(*header))
header++;
len = strlen(header);
if(len > 0) {
result = Curl_base64_decode(header, (unsigned char **)&input_token.value,
&rawlen);
if(result)
return result;
if(!rawlen) {
infof(data, "Negotiate handshake failure (empty challenge message)\n");
return CURLE_BAD_CONTENT_ENCODING;
}
input_token.length = rawlen;
DEBUGASSERT(input_token.value != NULL);
}
major_status = Curl_gss_init_sec_context(data,
&minor_status,
&neg_ctx->context,
neg_ctx->server_name,
&Curl_spnego_mech_oid,
GSS_C_NO_CHANNEL_BINDINGS,
&input_token,
&output_token,
TRUE,
NULL);
Curl_safefree(input_token.value);
neg_ctx->status = major_status;
if(GSS_ERROR(major_status)) {
if(output_token.value)
gss_release_buffer(&discard_st, &output_token);
Curl_gss_log_error(conn->data, minor_status,
"gss_init_sec_context() failed: ");
return CURLE_OUT_OF_MEMORY;
}
if(!output_token.value || !output_token.length) {
if(output_token.value)
gss_release_buffer(&discard_st, &output_token);
return CURLE_OUT_OF_MEMORY;
}
neg_ctx->output_token = output_token;
return CURLE_OK;
}
