ncacn_http: Authentication modules for http library

Signed-off-by: Samuel Cabrero <samuelcabrero@kernevil.me>
Reviewed-by: Stefan Metzmacher <metze@samba.org>
Reviewed-by: Andrew Bartlett <abartlet@samba.org>

1 files changed, 361 insertions, 0 deletions

diff --git a/source4/lib/http/http_auth.c b/source4/lib/http/http_auth.c
new file mode 100644
index 0000000000..2bf4392e8f
--- /dev/null
+++ b/source4/lib/http/http_auth.c
@@ -0,0 +1,361 @@
+/*
+   Unix SMB/CIFS implementation.
+
+   HTTP library
+
+   Copyright (C) 2014 Samuel Cabrero <samuelcabrero@kernevil.me>
+
+   This program is free software; you can redistribute it and/or modify
+   it under the terms of the GNU General Public License as published by
+   the Free Software Foundation; either version 3 of the License, or
+   (at your option) any later version.
+
+   This program is distributed in the hope that it will be useful,
+   but WITHOUT ANY WARRANTY; without even the implied warranty of
+   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+   GNU General Public License for more details.
+
+   You should have received a copy of the GNU General Public License
+   along with this program.  If not, see <http://www.gnu.org/licenses/>.
+*/
+
+#include "includes.h"
+#include "http.h"
+#include "http_internal.h"
+#include "lib/util/tevent_ntstatus.h"
+#include "lib/param/param.h"
+#include "tevent.h"
+#include "auth/gensec/gensec.h"
+#include "auth/credentials/credentials.h"
+#include "lib/util/data_blob.h"
+
+/**
+ * Copy the request headers from src to dst
+ */
+static NTSTATUS http_copy_header(struct http_request *src,
+				 struct http_request *dst)
+{
+	struct http_header *h;
+
+	dst->type = src->type;
+	dst->major = src->major;
+	dst->minor = src->minor;
+	dst->uri = talloc_strdup(dst, src->uri);
+
+	for (h = src->headers; h != NULL; h = h->next) {
+		http_add_header(dst, &dst->headers, h->key, h->value);
+	}
+	dst->headers_size = src->headers_size;
+
+	return NT_STATUS_OK;
+}
+
+/*
+ * Retrieve the WWW-Authenticate header from server response based on the
+ * authentication scheme being used.
+ */
+static NTSTATUS http_parse_auth_response(enum http_auth_method auth,
+					 struct http_request *auth_response,
+					 DATA_BLOB *in)
+{
+	struct http_header *h;
+
+	for (h = auth_response->headers; h != NULL; h = h->next) {
+		if (strncasecmp(h->key, "WWW-Authenticate", 16) == 0) {
+			switch (auth) {
+			case HTTP_AUTH_NTLM:
+				if (strncasecmp(h->value, "NTLM ", 5) == 0) {
+					*in = data_blob_string_const(h->value);
+					return NT_STATUS_OK;
+				}
+				break;
+			default:
+				break;
+			}
+		}
+	}
+
+	return NT_STATUS_NOT_SUPPORTED;
+}
+
+/*
+ * Create the next authentication request to send to server if authentication
+ * is not completed. If it is completed, attachs the 'Authorization' header
+ * to the original request.
+ */
+static NTSTATUS http_create_auth_request(TALLOC_CTX *mem_ctx,
+					 struct gensec_security *gensec_ctx,
+					 struct tevent_context *ev,
+					 enum http_auth_method auth,
+					 struct http_request *original_request,
+					 struct http_request *auth_response,
+					 struct http_request **auth_request)
+{
+	NTSTATUS status;
+	DATA_BLOB in, out;
+
+	if (auth_response) {
+		status = http_parse_auth_response(auth, auth_response, &in);
+	} else {
+		in = data_blob_null;
+	}
+
+	status = gensec_update_ev(gensec_ctx, mem_ctx, ev, in, &out);
+	if (NT_STATUS_IS_OK(status)) {
+		if (out.length) {
+			http_add_header(original_request,
+					&original_request->headers,
+					"Authorization", (char*)out.data);
+		}
+	}
+
+	if (NT_STATUS_EQUAL(status, NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+		NTSTATUS status2;
+
+		*auth_request = talloc_zero(mem_ctx, struct http_request);
+		if (*auth_request == NULL) {
+			return NT_STATUS_NO_MEMORY;
+		}
+
+		status2 = http_copy_header(original_request, *auth_request);
+		if (!NT_STATUS_IS_OK(status2)) {
+			talloc_free(*auth_request);
+			return status2;
+		}
+
+		http_replace_header(*auth_request, &((*auth_request)->headers),
+				    "Content-Length", "0");
+		if (out.length) {
+			http_add_header(*auth_request,
+					&((*auth_request)->headers),
+					"Authorization", (char*)out.data);
+		}
+	}
+
+	return status;
+}
+
+struct http_auth_state
+{
+	struct loadparm_context	*lp_ctx;
+	struct tevent_context	*ev;
+	struct tstream_context	*stream;
+	struct tevent_queue	*send_queue;
+	struct cli_credentials  *credentials;
+	struct http_request	*original_request;
+	struct gensec_security	*gensec_ctx;
+	NTSTATUS		gensec_status;
+	enum http_auth_method	auth;
+
+	int			sys_errno;
+	int			nwritten;
+};
+
+
+static void http_send_auth_request_done(struct tevent_req *);
+struct tevent_req *http_send_auth_request_send(TALLOC_CTX *mem_ctx,
+					       struct tevent_context *ev,
+					       struct tstream_context *stream,
+					       struct tevent_queue *send_queue,
+					       struct http_request *original_request,
+					       struct cli_credentials *credentials,
+					       struct loadparm_context *lp_ctx,
+					       enum http_auth_method auth)
+{
+	struct tevent_req *req;
+	struct tevent_req *subreq;
+	struct http_auth_state *state;
+	NTSTATUS status;
+	struct http_request *auth_request;
+	struct http_request *request_to_send;
+
+	req = tevent_req_create(mem_ctx, &state, struct http_auth_state);
+	if (req == NULL) {
+		return NULL;
+	}
+
+	state->ev = ev;
+	state->stream = stream;
+	state->send_queue = send_queue;
+	state->original_request = original_request;
+	state->credentials = credentials;
+	state->lp_ctx = lp_ctx;
+	state->auth = auth;
+
+	status = gensec_init();
+	if (!NT_STATUS_IS_OK(status)) {
+		goto post_status;
+	}
+	status = gensec_client_start(state, &state->gensec_ctx,
+			             lpcfg_gensec_settings(state, lp_ctx));
+	if (!NT_STATUS_IS_OK(status)) {
+		goto post_status;
+	}
+	status = gensec_set_credentials(state->gensec_ctx, credentials);
+	if (!NT_STATUS_IS_OK(status)) {
+		goto post_status;
+	}
+
+	switch (state->auth) {
+	case HTTP_AUTH_BASIC:
+		status = gensec_start_mech_by_name(state->gensec_ctx,
+						   "http_basic");
+		if (!NT_STATUS_IS_OK(status)) {
+			goto post_status;
+		}
+		break;
+	case HTTP_AUTH_NTLM:
+		status = gensec_start_mech_by_name(state->gensec_ctx,
+						   "http_ntlm");
+		if (!NT_STATUS_IS_OK(status)) {
+			goto post_status;
+		}
+		break;
+	default:
+		tevent_req_nterror(req, NT_STATUS_NOT_SUPPORTED);
+		return tevent_req_post(req, ev);
+	}
+
+	/*
+	 * Store the gensec status to read the server response on callback
+	 * if more processing is required
+	*/
+	state->gensec_status = http_create_auth_request(state,
+							state->gensec_ctx,
+							state->ev,
+							state->auth,
+							state->original_request,
+							NULL,
+							&auth_request);
+	if (!NT_STATUS_IS_OK(state->gensec_status) &&
+	    !NT_STATUS_EQUAL(state->gensec_status,
+			     NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+		goto post_status;
+	}
+
+	/*
+	 * If no more processing is necessary, the http_create_auth_request
+	 * function will attach the authentication header to the original
+	 * request
+	 */
+	request_to_send = NT_STATUS_IS_OK(state->gensec_status) ?
+				state->original_request : auth_request;
+
+	subreq = http_send_request_send(state, ev, stream, send_queue,
+					request_to_send);
+	if (tevent_req_nomem(subreq, req)) {
+		return tevent_req_post(req, ev);
+	}
+	tevent_req_set_callback(subreq, http_send_auth_request_done, req);
+	return req;
+post_status:
+	tevent_req_nterror(req, status);
+	return tevent_req_post(req, ev);
+}
+
+static void http_send_auth_request_done2(struct tevent_req *subreq);
+static void http_send_auth_request_done(struct tevent_req *subreq)
+{
+	NTSTATUS		status;
+	struct tevent_req	*req;
+	struct http_auth_state	*state;
+
+	req = tevent_req_callback_data(subreq, struct tevent_req);
+	state = tevent_req_data(req, struct http_auth_state);
+
+	status = http_send_request_recv(subreq);
+	TALLOC_FREE(subreq);
+	if (tevent_req_nterror(req, status)) {
+		return;
+	}
+
+	/* If no more processing required, it is done */
+	if (NT_STATUS_IS_OK(state->gensec_status)) {
+		tevent_req_done(req);
+		return;
+	}
+
+	/* If more processing required, read the response from server */
+	if (NT_STATUS_EQUAL(state->gensec_status,
+			    NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+		subreq = http_read_response_send(state, state->ev,
+						 state->stream);
+		if (tevent_req_nomem(subreq, req)) {
+			return;
+		}
+		tevent_req_set_callback(subreq, http_send_auth_request_done2,
+					req);
+		return;
+	}
+
+	/*
+	 * If gensec status is not NT_STATUS_OK neither
+	 * NT_STATUS_MORE_PROCESSING_REQUIRED , it is an error
+	 */
+	tevent_req_nterror(req, state->gensec_status);
+}
+
+static void http_send_auth_request_done2(struct tevent_req *subreq)
+{
+	NTSTATUS status;
+	struct tevent_req	*req;
+	struct http_auth_state	*state;
+	struct http_request *auth_response;
+	struct http_request *auth_request;
+	struct http_request *request_to_send;
+
+	req = tevent_req_callback_data(subreq, struct tevent_req);
+	state = tevent_req_data(req, struct http_auth_state);
+
+	status = http_read_response_recv(subreq, state, &auth_response);
+	TALLOC_FREE(subreq);
+	if (tevent_req_nterror(req, status)) {
+		return;
+	}
+
+	state->gensec_status = http_create_auth_request(state,
+							state->gensec_ctx,
+							state->ev,
+							state->auth,
+							state->original_request,
+							auth_response,
+							&auth_request);
+	if (!NT_STATUS_IS_OK(state->gensec_status) &&
+	    !NT_STATUS_EQUAL(state->gensec_status,
+			     NT_STATUS_MORE_PROCESSING_REQUIRED)) {
+		tevent_req_nterror(req, status);
+		return;
+	}
+
+	/*
+	 * If no more processing is necessary, the http_create_auth_request
+	 * function will attach the authentication header to the original
+	 * request
+	 */
+	request_to_send = NT_STATUS_IS_OK(state->gensec_status) ?
+				state->original_request : auth_request;
+
+	subreq = http_send_request_send(state,
+					state->ev,
+					state->stream,
+					state->send_queue,
+					request_to_send);
+	if (tevent_req_nomem(subreq, req)) {
+		return;
+	}
+	tevent_req_set_callback(subreq, http_send_auth_request_done, req);
+}
+
+
+NTSTATUS http_send_auth_request_recv(struct tevent_req *req)
+{
+	NTSTATUS status;
+
+	if (tevent_req_is_nterror(req, &status)) {
+		tevent_req_received(req);
+		return status;
+	}
+	tevent_req_received(req);
+
+	return NT_STATUS_OK;
+}