Not all headers in HTTP, RTSP, SIP, etc. are entity headers; rename some

files, routines, data structures, etc..

svn path=/trunk/; revision=9428

1 files changed, 170 insertions, 0 deletions

diff --git a/req_resp_hdrs.c b/req_resp_hdrs.c
new file mode 100644
index 0000000000..a1aef35a17
--- /dev/null
+++ b/req_resp_hdrs.c
@@ -0,0 +1,170 @@
+/* req_resp_hdrs.c
+ * Routines handling protocols with a request/response line, headers,
+ * a blank line, and an optional body.
+ *
+ * $Id: req_resp_hdrs.c,v 1.1 2003/12/23 02:29:11 guy Exp $
+ *
+ * Ethereal - Network traffic analyzer
+ * By Gerald Combs <gerald@ethereal.com>
+ * Copyright 1998 Gerald Combs
+ *
+ * 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 (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, write to the Free Software
+ * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA  02111-1307, USA.
+ */
+
+#ifdef HAVE_CONFIG_H
+#include "config.h"
+#endif
+
+#include <glib.h>
+#include <epan/packet.h>
+#include <epan/strutil.h>
+
+#include "req_resp_hdrs.h"
+
+/*
+ * Optionally do reassembly of the request/response line, headers, and body.
+ */
+gboolean
+req_resp_hdrs_do_reassembly(tvbuff_t *tvb, packet_info *pinfo,
+    gboolean desegment_headers, gboolean desegment_body)
+{
+	gint		offset = 0;
+	gint		next_offset;
+	gint		next_offset_sav;
+	int		linelen;
+	long int	content_length;
+	gboolean	content_length_found = FALSE;
+
+	/*
+	 * Do header desegmentation if we've been told to.
+	 *
+	 * RFC 2616 defines HTTP messages as being either of the
+	 * Request or the Response type
+	 * (HTTP-message = Request | Response).
+	 * Request and Response are defined as:
+	 *     Request = Request-Line
+	 *         *(( general-header
+	 *         | request-header
+	 *         | entity-header ) CRLF)
+	 *         CRLF
+	 *         [ message-body ]
+	 *     Response = Status-Line
+	 *         *(( general-header
+	 *         | response-header
+	 *         | entity-header ) CRLF)
+	 *         CRLF
+	 *         [ message-body ]
+	 * that's why we can always assume two consecutive line
+	 * endings (we allow CR, LF, or CRLF, as some clients
+	 * or servers might not use a full CRLF) to mark the end
+	 * of the headers.  The worst thing that would happen
+	 * otherwise would be the packet not being desegmented
+	 * or being interpreted as only headers.
+	 *
+	 * RFC 2326 says RTSP works the same way; RFC 3261 says SIP
+	 * works the same way.
+	 */
+
+	/*
+	 * If header desegmentation is activated, check that all
+	 * headers are in this tvbuff (search for an empty line
+	 * marking end of headers) or request one more byte (we
+	 * don't know how many bytes we'll need, so we just ask
+	 * for one).
+	 */
+	if (desegment_headers && pinfo->can_desegment) {
+		next_offset = offset;
+		for (;;) {
+			next_offset_sav = next_offset;
+
+			/*
+			 * Request one more byte if there're no
+			 * bytes left.
+			 */
+			if (tvb_offset_exists(tvb, next_offset) == FALSE) {
+				pinfo->desegment_offset = offset;
+				pinfo->desegment_len = 1;
+				return FALSE;
+			}
+
+			/*
+			 * Request one more byte if we cannot find a
+			 * header (i.e. a line end).
+			 */
+			linelen = tvb_find_line_end(tvb, next_offset,
+			    -1, &next_offset, TRUE);
+			if (linelen == -1) {
+				/*
+				 * Not enough data; ask for one more
+				 * byte.
+				 */
+				pinfo->desegment_offset = offset;
+				pinfo->desegment_len = 1;
+				return FALSE;
+			} else if (linelen == 0) {
+				/*
+				 * We found the end of the headers.
+				 */
+				break;
+			}
+
+			/*
+			 * Is this a Content-Length header?
+			 * If not, it either means that we are in
+			 * a different header line, or that we are
+			 * at the end of the headers, or that there
+			 * isn't enough data; the two latter cases
+			 * have already been handled above.
+			 */
+			if (desegment_body) {
+				/*
+				 * Check if we've found Content-Length.
+				 */
+				if (tvb_strneql(tvb, next_offset_sav,
+				    "Content-Length:", 15) == 0) {
+					if (sscanf(
+					    tvb_get_string(tvb,
+					        next_offset_sav + 15,
+					        linelen - 15),
+					    "%li", &content_length)
+					    == 1)
+						content_length_found = TRUE;
+				}
+			}
+		}
+	}
+
+	/*
+	 * The above loop ends when we reached the end of the headers, so
+	 * there should be content_length byte after the 4 terminating bytes
+	 * and next_offset points to after the end of the headers.
+	 */
+	if (desegment_body && content_length_found) {
+		/* next_offset has been set because content-length was found */
+		if (!tvb_bytes_exist(tvb, next_offset, content_length)) {
+			gint length = tvb_length_remaining(tvb, next_offset);
+			if (length == -1)
+				length = 0;
+			pinfo->desegment_offset = offset;
+			pinfo->desegment_len = content_length - length;
+			return FALSE;
+		}
+	}
+
+	/*
+	 * No further desegmentation needed.
+	 */
+	return TRUE;
+}