[http] Add support for NTLM authentication

Signed-off-by: Michael Brown <mcb30@ipxe.org>

1 files changed, 201 insertions, 0 deletions

diff --git a/src/net/tcp/httpntlm.c b/src/net/tcp/httpntlm.c
new file mode 100644
index 00000000..00238e96
--- /dev/null
+++ b/src/net/tcp/httpntlm.c
@@ -0,0 +1,201 @@
+/*
+ * Copyright (C) 2017 Michael Brown <mbrown@fensystems.co.uk>.
+ *
+ * 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 2 of the
+ * License, or 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, write to the Free Software
+ * Foundation, Inc., 51 Franklin Street, Fifth Floor, Boston, MA
+ * 02110-1301, USA.
+ *
+ * You can also choose to distribute this program under the terms of
+ * the Unmodified Binary Distribution Licence (as given in the file
+ * COPYING.UBDL), provided that you have satisfied its requirements.
+ */
+
+FILE_LICENCE ( GPL2_OR_LATER_OR_UBDL );
+
+/**
+ * @file
+ *
+ * Hyper Text Transfer Protocol (HTTP) NTLM authentication
+ *
+ */
+
+#include <string.h>
+#include <errno.h>
+#include <ipxe/uri.h>
+#include <ipxe/base64.h>
+#include <ipxe/ntlm.h>
+#include <ipxe/http.h>
+
+struct http_authentication http_ntlm_auth __http_authentication;
+
+/** Workstation name used for NTLM authentication */
+static const char http_ntlm_workstation[] = "iPXE";
+
+/**
+ * Parse HTTP "WWW-Authenticate" header for NTLM authentication
+ *
+ * @v http		HTTP transaction
+ * @v line		Remaining header line
+ * @ret rc		Return status code
+ */
+static int http_parse_ntlm_auth ( struct http_transaction *http, char *line ) {
+	struct http_response_auth_ntlm *rsp = &http->response.auth.ntlm;
+	char *copy;
+	int len;
+	int rc;
+
+	/* Create temporary copy of Base64-encoded challenge message */
+	copy = strdup ( line );
+	if ( ! copy ) {
+		rc = -ENOMEM;
+		goto err_alloc;
+	}
+
+	/* Decode challenge message, overwriting the original */
+	len = base64_decode ( copy, line, strlen ( line ) );
+	if ( len < 0 ) {
+		rc = len;
+		DBGC ( http, "HTTP %p could not decode NTLM challenge "
+		       "\"%s\": %s\n", http, copy, strerror ( rc ) );
+		goto err_decode;
+	}
+
+	/* Parse challenge, if present */
+	if ( len ) {
+		rsp->challenge = ( ( void * ) line );
+		if ( ( rc = ntlm_challenge ( rsp->challenge, len,
+					     &rsp->info ) ) != 0 ) {
+			DBGC ( http, "HTTP %p could not parse NTLM challenge: "
+			       "%s\n", http, strerror ( rc ) );
+			goto err_challenge;
+		}
+	}
+
+	/* Allow HTTP request to be retried if the request had not
+	 * already tried authentication.  Note that NTLM requires an
+	 * additional round trip to obtain the challenge message,
+	 * which is not present in the initial WWW-Authenticate.
+	 */
+	if ( ( http->request.auth.auth == NULL ) ||
+	     ( ( http->request.auth.auth == &http_ntlm_auth ) &&
+	       ( http->request.auth.ntlm.len == 0 ) && len ) ) {
+		http->response.flags |= HTTP_RESPONSE_RETRY;
+	}
+
+	/* Success */
+	rc = 0;
+
+ err_challenge:
+ err_decode:
+	free ( copy );
+ err_alloc:
+	return rc;
+}
+
+/**
+ * Perform HTTP NTLM authentication
+ *
+ * @v http		HTTP transaction
+ * @ret rc		Return status code
+ */
+static int http_ntlm_authenticate ( struct http_transaction *http ) {
+	struct http_request_auth_ntlm *req = &http->request.auth.ntlm;
+	struct http_response_auth_ntlm *rsp = &http->response.auth.ntlm;
+	struct ntlm_key key;
+	const char *password;
+
+	/* If we have no challenge yet, then just send a Negotiate message */
+	if ( ! rsp->challenge ) {
+		DBGC ( http, "HTTP %p sending NTLM Negotiate\n", http );
+		return 0;
+	}
+
+	/* Record username */
+	if ( ! http->uri->user ) {
+		DBGC ( http, "HTTP %p has no username for NTLM "
+		       "authentication\n", http );
+		return -EACCES;
+	}
+	req->username = http->uri->user;
+	password = ( http->uri->password ? http->uri->password : "" );
+
+	/* Generate key */
+	ntlm_key ( NULL, req->username, password, &key );
+
+	/* Generate responses */
+	ntlm_response ( &rsp->info, &key, NULL, &req->lm, &req->nt );
+
+	/* Calculate Authenticate message length */
+	req->len = ntlm_authenticate_len ( &rsp->info, NULL, req->username,
+					   http_ntlm_workstation );
+
+	return 0;
+}
+
+/**
+ * Construct HTTP "Authorization" header for NTLM authentication
+ *
+ * @v http		HTTP transaction
+ * @v buf		Buffer
+ * @v len		Length of buffer
+ * @ret len		Length of header value, or negative error
+ */
+static int http_format_ntlm_auth ( struct http_transaction *http,
+				   char *buf, size_t len ) {
+	struct http_request_auth_ntlm *req = &http->request.auth.ntlm;
+	struct http_response_auth_ntlm *rsp = &http->response.auth.ntlm;
+	struct ntlm_authenticate *auth;
+	size_t check;
+
+	/* If we have no challenge yet, then just send a Negotiate message */
+	if ( ! rsp->challenge ) {
+		return base64_encode ( &ntlm_negotiate,
+				       sizeof ( ntlm_negotiate ), buf, len );
+	}
+
+	/* Skip allocation if just calculating length */
+	if ( ! len )
+		return base64_encoded_len ( req->len );
+
+	/* Allocate temporary buffer for Authenticate message */
+	auth = malloc ( req->len );
+	if ( ! auth )
+		return -ENOMEM;
+
+	/* Construct raw Authenticate message */
+	check = ntlm_authenticate ( &rsp->info, NULL, req->username,
+				    http_ntlm_workstation, &req->lm,
+				    &req->nt, auth );
+	assert ( check == req->len );
+
+	/* Base64-encode Authenticate message */
+	len = base64_encode ( auth, req->len, buf, len );
+
+	/* Free raw Authenticate message */
+	free ( auth );
+
+	return len;
+}
+
+/** HTTP NTLM authentication scheme */
+struct http_authentication http_ntlm_auth __http_authentication = {
+	.name = "NTLM",
+	.parse = http_parse_ntlm_auth,
+	.authenticate = http_ntlm_authenticate,
+	.format = http_format_ntlm_auth,
+};
+
+/* Drag in HTTP authentication support */
+REQUIRING_SYMBOL ( http_ntlm_auth );
+REQUIRE_OBJECT ( httpauth );