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/* packet-rtsp.c
* Routines for RTSP packet disassembly (RFC 2326)
*
* Jason Lango <jal@netapp.com>
* Liberally copied from packet-http.c, by Guy Harris <guy@alum.mit.edu>
*
* $Id: packet-rtsp.c,v 1.60 2004/01/05 03:51:28 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.
*/
#include "config.h"
#include <string.h>
#include <ctype.h>
#include <stdlib.h>
#include "prefs.h"
#include <glib.h>
#include <epan/packet.h>
#include "req_resp_hdrs.h"
#include "packet-rtp.h"
#include "packet-rtcp.h"
#include <epan/conversation.h>
#include <epan/strutil.h>
static int proto_rtsp = -1;
static gint ett_rtsp = -1;
static gint ett_rtspframe = -1;
static int hf_rtsp_method = -1;
static int hf_rtsp_url = -1;
static int hf_rtsp_status = -1;
static dissector_handle_t sdp_handle;
static dissector_handle_t rtp_handle;
static dissector_handle_t rtcp_handle;
void proto_reg_handoff_rtsp(void);
static GMemChunk *rtsp_vals = NULL;
#define rtsp_hash_init_count 20
/*
* desegmentation of RTSP headers
* (when we are over TCP or another protocol providing the desegmentation API)
*/
static gboolean rtsp_desegment_headers = FALSE;
/*
* desegmentation of RTSP bodies
* (when we are over TCP or another protocol providing the desegmentation API)
* TODO let the user filter on content-type the bodies he wants desegmented
*/
static gboolean rtsp_desegment_body = FALSE;
/* http://www.iana.org/assignments/port-numberslists two rtsp ports */
#define TCP_PORT_RTSP 554
#define TCP_ALTERNATE_PORT_RTSP 8554
static guint global_rtsp_tcp_port = TCP_PORT_RTSP;
static guint global_rtsp_tcp_alternate_port = TCP_ALTERNATE_PORT_RTSP;
/*
* Variables to allow for proper deletion of dissector registration when
* the user changes port from the gui.
*/
static guint tcp_port = 0;
static guint tcp_alternate_port = 0;
/*
* Takes an array of bytes, assumed to contain a null-terminated
* string, as an argument, and returns the length of the string -
* i.e., the size of the array, minus 1 for the null terminator.
*/
#define STRLEN_CONST(str) (sizeof (str) - 1)
#define RTSP_FRAMEHDR ('$')
typedef struct {
dissector_handle_t dissector;
} rtsp_interleaved_t;
#define RTSP_MAX_INTERLEAVED (8)
/*
* Careful about dynamically allocating memory in this structure (say
* for dynamically increasing the size of the 'interleaved' array) -
* the containing structure is garbage collected and contained
* pointers will not be freed.
*/
typedef struct {
rtsp_interleaved_t interleaved[RTSP_MAX_INTERLEAVED];
} rtsp_conversation_data_t;
static int
dissect_rtspinterleaved(tvbuff_t *tvb, int offset, packet_info *pinfo,
proto_tree *tree)
{
guint length_remaining;
proto_item *ti;
proto_tree *rtspframe_tree = NULL;
int orig_offset;
guint8 rf_start; /* always RTSP_FRAMEHDR */
guint8 rf_chan; /* interleaved channel id */
guint16 rf_len; /* packet length */
tvbuff_t *next_tvb;
conversation_t *conv;
rtsp_conversation_data_t *data;
dissector_handle_t dissector;
/*
* This will throw an exception if we don't have any data left.
* That's what we want. (See "tcp_dissect_pdus()", which is
* similar.)
*/
length_remaining = tvb_ensure_length_remaining(tvb, offset);
/*
* Can we do reassembly?
*/
if (rtsp_desegment_headers && pinfo->can_desegment) {
/*
* Yes - would an RTSP multiplexed header starting at
* this offset be split across segment boundaries?
*/
if (length_remaining < 4) {
/*
* Yes. Tell the TCP dissector where the data
* for this message starts in the data it handed
* us, and how many more bytes we need, and return.
*/
pinfo->desegment_offset = offset;
pinfo->desegment_len = 4 - length_remaining;
return -1;
}
}
/*
* Get the "$", channel, and length from the header.
*/
orig_offset = offset;
rf_start = tvb_get_guint8(tvb, offset);
rf_chan = tvb_get_guint8(tvb, offset+1);
rf_len = tvb_get_ntohs(tvb, offset+2);
/*
* Can we do reassembly?
*/
if (rtsp_desegment_body && pinfo->can_desegment) {
/*
* Yes - is the header + encapsulated packet split
* across segment boundaries?
*/
if (length_remaining < 4U + rf_len) {
/*
* Yes. Tell the TCP dissector where the data
* for this message starts in the data it handed
* us, and how many more bytes we need, and return.
*/
pinfo->desegment_offset = offset;
pinfo->desegment_len = 4U + rf_len - length_remaining;
return -1;
}
}
if (check_col(pinfo->cinfo, COL_INFO))
col_add_fstr(pinfo->cinfo, COL_INFO,
"Interleaved channel 0x%02x, %u bytes",
rf_chan, rf_len);
if (tree != NULL) {
ti = proto_tree_add_protocol_format(tree, proto_rtsp, tvb,
offset, 4,
"RTSP Interleaved Frame, Channel: 0x%02x, %u bytes",
rf_chan, rf_len);
rtspframe_tree = proto_item_add_subtree(ti, ett_rtspframe);
proto_tree_add_text(rtspframe_tree, tvb, offset, 1,
"Magic: 0x%02x",
rf_start);
}
offset += 1;
if (tree != NULL) {
proto_tree_add_text(rtspframe_tree, tvb, offset, 1,
"Channel: 0x%02x",
rf_chan);
}
offset += 1;
if (tree != NULL) {
proto_tree_add_text(rtspframe_tree, tvb, offset, 2,
"Length: %u bytes",
rf_len);
}
offset += 2;
/*
* We set the actual length of the tvbuff for the interleaved
* stuff to the minimum of what's left in the tvbuff and the
* length in the header.
*
* XXX - what if there's nothing left in the tvbuff?
* We'd want a BoundsError exception to be thrown, so
* that a Short Frame would be reported.
*/
if (length_remaining > rf_len)
length_remaining = rf_len;
next_tvb = tvb_new_subset(tvb, offset, length_remaining, rf_len);
conv = find_conversation(&pinfo->src, &pinfo->dst, pinfo->ptype,
pinfo->srcport, pinfo->destport, 0);
if (conv &&
(data = conversation_get_proto_data(conv, proto_rtsp)) &&
rf_chan < RTSP_MAX_INTERLEAVED &&
(dissector = data->interleaved[rf_chan].dissector)) {
call_dissector(dissector, next_tvb, pinfo, tree);
} else {
proto_tree_add_text(rtspframe_tree, tvb, offset, rf_len,
"Data (%u bytes)", rf_len);
}
offset += rf_len;
return offset - orig_offset;
}
static void process_rtsp_request(tvbuff_t *tvb, int offset, const guchar *data,
size_t linelen, proto_tree *tree);
static void process_rtsp_reply(tvbuff_t *tvb, int offset, const guchar *data,
size_t linelen, proto_tree *tree);
typedef enum {
RTSP_REQUEST,
RTSP_REPLY,
NOT_RTSP
} rtsp_type_t;
static const char *rtsp_methods[] = {
"DESCRIBE", "ANNOUNCE", "GET_PARAMETER", "OPTIONS",
"PAUSE", "PLAY", "RECORD", "REDIRECT", "SETUP",
"SET_PARAMETER", "TEARDOWN"
};
#define RTSP_NMETHODS (sizeof rtsp_methods / sizeof rtsp_methods[0])
static gboolean
is_rtsp_request_or_reply(const guchar *line, size_t linelen, rtsp_type_t *type)
{
unsigned ii;
/* Is this an RTSP reply? */
if (linelen >= 5 && strncasecmp("RTSP/", line, 5) == 0) {
/*
* Yes.
*/
*type = RTSP_REPLY;
return TRUE;
}
/*
* Is this an RTSP request?
* Check whether the line begins with one of the RTSP request
* methods.
*/
for (ii = 0; ii < RTSP_NMETHODS; ii++) {
size_t len = strlen(rtsp_methods[ii]);
if (linelen >= len &&
strncasecmp(rtsp_methods[ii], line, len) == 0) {
*type = RTSP_REQUEST;
return TRUE;
}
}
*type = NOT_RTSP;
return FALSE;
}
static const char rtsp_content_type[] = "Content-Type:";
static int
is_content_sdp(const guchar *line, size_t linelen)
{
static const char type[] = "application/sdp";
size_t typelen = STRLEN_CONST(type);
line += STRLEN_CONST(rtsp_content_type);
linelen -= STRLEN_CONST(rtsp_content_type);
while (linelen > 0 && (*line == ' ' || *line == '\t')) {
line++;
linelen--;
}
if (linelen < typelen || strncasecmp(type, line, typelen))
return FALSE;
line += typelen;
linelen -= typelen;
if (linelen > 0 && !isspace(*line))
return FALSE;
return TRUE;
}
static const char rtsp_transport[] = "Transport:";
static const char rtsp_sps[] = "server_port=";
static const char rtsp_cps[] = "client_port=";
static const char rtsp_rtp[] = "rtp/";
static const char rtsp_inter[] = "interleaved=";
static void
rtsp_create_conversation(packet_info *pinfo, const guchar *line_begin,
size_t line_len)
{
conversation_t *conv;
guchar buf[256];
guchar *tmp;
guint c_data_port, c_mon_port;
guint s_data_port, s_mon_port;
address null_addr;
if (line_len > sizeof(buf) - 1) {
/*
* Don't overflow the buffer.
*/
line_len = sizeof(buf) - 1;
}
memcpy(buf, line_begin, line_len);
buf[line_len] = '\0';
tmp = buf + STRLEN_CONST(rtsp_transport);
while (*tmp && isspace(*tmp))
tmp++;
if (strncasecmp(tmp, rtsp_rtp, strlen(rtsp_rtp)) != 0) {
g_warning("Frame %u: rtsp: unknown transport", pinfo->fd->num);
return;
}
c_data_port = c_mon_port = 0;
s_data_port = s_mon_port = 0;
if ((tmp = strstr(buf, rtsp_sps))) {
tmp += strlen(rtsp_sps);
if (sscanf(tmp, "%u-%u", &s_data_port, &s_mon_port) < 1) {
g_warning("Frame %u: rtsp: bad server_port",
pinfo->fd->num);
return;
}
}
if ((tmp = strstr(buf, rtsp_cps))) {
tmp += strlen(rtsp_cps);
if (sscanf(tmp, "%u-%u", &c_data_port, &c_mon_port) < 1) {
g_warning("Frame %u: rtsp: bad client_port",
pinfo->fd->num);
return;
}
}
if (!c_data_port) {
rtsp_conversation_data_t *data;
guint s_data_chan, s_mon_chan;
int i;
/*
* Deal with RTSP TCP-interleaved conversations.
*/
if ((tmp = strstr(buf, rtsp_inter)) == NULL) {
/*
* No interleaved or server_port - probably a
* SETUP request, rather than reply.
*/
return;
}
tmp += strlen(rtsp_inter);
i = sscanf(tmp, "%u-%u", &s_data_chan, &s_mon_chan);
if (i < 1) {
g_warning("Frame %u: rtsp: bad interleaved",
pinfo->fd->num);
return;
}
conv = find_conversation(&pinfo->src, &pinfo->dst, pinfo->ptype,
pinfo->srcport, pinfo->destport, 0);
if (!conv) {
conv = conversation_new(&pinfo->src, &pinfo->dst,
pinfo->ptype, pinfo->srcport, pinfo->destport,
0);
}
data = conversation_get_proto_data(conv, proto_rtsp);
if (!data) {
data = g_mem_chunk_alloc(rtsp_vals);
conversation_add_proto_data(conv, proto_rtsp, data);
}
if (s_data_chan < RTSP_MAX_INTERLEAVED) {
data->interleaved[s_data_chan].dissector =
rtp_handle;
}
if (i > 1 && s_mon_chan < RTSP_MAX_INTERLEAVED) {
data->interleaved[s_mon_chan].dissector =
rtcp_handle;
}
return;
}
/*
* We only want to match on the destination address, not the
* source address, because the server might send back a packet
* from an address other than the address to which its client
* sent the packet, so we construct a conversation with no
* second address.
*/
SET_ADDRESS(&null_addr, pinfo->src.type, 0, NULL);
conv = conversation_new(&pinfo->dst, &null_addr, PT_UDP, c_data_port,
s_data_port, NO_ADDR2 | (!s_data_port ? NO_PORT2 : 0));
conversation_set_dissector(conv, rtp_handle);
if (!c_mon_port)
return;
conv = conversation_new(&pinfo->dst, &null_addr, PT_UDP, c_mon_port,
s_mon_port, NO_ADDR2 | (!s_mon_port ? NO_PORT2 : 0));
conversation_set_dissector(conv, rtcp_handle);
}
static const char rtsp_content_length[] = "Content-Length:";
static int
rtsp_get_content_length(const guchar *line_begin, size_t line_len)
{
guchar buf[256];
guchar *tmp;
long content_length;
char *p;
guchar *up;
if (line_len > sizeof(buf) - 1) {
/*
* Don't overflow the buffer.
*/
line_len = sizeof(buf) - 1;
}
memcpy(buf, line_begin, line_len);
buf[line_len] = '\0';
tmp = buf + STRLEN_CONST(rtsp_content_length);
while (*tmp && isspace(*tmp))
tmp++;
content_length = strtol(tmp, &p, 10);
up = p;
if (up == tmp || (*up != '\0' && !isspace(*up)))
return -1; /* not a valid number */
return content_length;
}
static int
dissect_rtspmessage(tvbuff_t *tvb, int offset, packet_info *pinfo,
proto_tree *tree)
{
proto_tree *rtsp_tree = NULL;
proto_item *ti = NULL;
const guchar *line;
gint next_offset;
const guchar *linep, *lineend;
int orig_offset;
int first_linelen, linelen;
gboolean is_request_or_reply;
gboolean body_requires_content_len;
gboolean saw_req_resp_or_header;
guchar c;
rtsp_type_t rtsp_type;
gboolean is_mime_header;
int is_sdp = FALSE;
int datalen;
int content_length;
int reported_datalen;
/*
* Is this a request or response?
*
* Note that "tvb_find_line_end()" will return a value that
* is not longer than what's in the buffer, so the
* "tvb_get_ptr()" call won't throw an exception.
*/
first_linelen = tvb_find_line_end(tvb, offset,
tvb_ensure_length_remaining(tvb, offset), &next_offset,
FALSE);
/*
* Is the first line a request or response?
*/
line = tvb_get_ptr(tvb, offset, first_linelen);
is_request_or_reply = is_rtsp_request_or_reply(line, first_linelen,
&rtsp_type);
if (is_request_or_reply) {
/*
* Yes, it's a request or response.
* Do header desegmentation if we've been told to,
* and do body desegmentation if we've been told to and
* we find a Content-Length header.
*/
if (!req_resp_hdrs_do_reassembly(tvb, pinfo,
rtsp_desegment_headers, rtsp_desegment_body)) {
/*
* More data needed for desegmentation.
*/
return -1;
}
}
/*
* RFC 2326 says that a content length must be specified
* in requests that have a body, although section 4.4 speaks
* of a server closing the connection indicating the end of
* a reply body.
*
* We assume that an absent content length in a request means
* that we don't have a body, and that an absent content length
* in a reply means that the reply body runs to the end of
* the connection. If the first line is neither, we assume
* that whatever follows a blank line should be treated as a
* body; there's not much else we can do, as we're jumping
* into the message in the middle.
*
* XXX - if there was no Content-Length entity header, we should
* accumulate all data until the end of the connection.
* That'd require that the TCP dissector call subdissectors
* for all frames with FIN, even if they contain no data,
* which would require subdissectors to deal intelligently
* with empty segments.
*/
if (rtsp_type == RTSP_REQUEST)
body_requires_content_len = TRUE;
else
body_requires_content_len = FALSE;
if (check_col(pinfo->cinfo, COL_PROTOCOL))
col_set_str(pinfo->cinfo, COL_PROTOCOL, "RTSP");
if (check_col(pinfo->cinfo, COL_INFO)) {
/*
* Put the first line from the buffer into the summary
* if it's an RTSP request or reply (but leave out the
* line terminator).
* Otherwise, just call it a continuation.
*
* Note that "tvb_find_line_end()" will return a value that
* is not longer than what's in the buffer, so the
* "tvb_get_ptr()" call won't throw an exception.
*/
line = tvb_get_ptr(tvb, offset, first_linelen);
if (is_request_or_reply)
col_add_str(pinfo->cinfo, COL_INFO,
format_text(line, first_linelen));
else
col_set_str(pinfo->cinfo, COL_INFO, "Continuation");
}
orig_offset = offset;
if (tree) {
ti = proto_tree_add_item(tree, proto_rtsp, tvb, offset, -1,
FALSE);
rtsp_tree = proto_item_add_subtree(ti, ett_rtsp);
}
/*
* We haven't yet seen a Content-Length header.
*/
content_length = -1;
/*
* Process the packet data, a line at a time.
*/
saw_req_resp_or_header = FALSE; /* haven't seen anything yet */
while (tvb_reported_length_remaining(tvb, offset) != 0) {
/*
* We haven't yet concluded that this is a MIME header.
*/
is_mime_header = FALSE;
/*
* Find the end of the line.
*/
linelen = tvb_find_line_end(tvb, offset,
tvb_ensure_length_remaining(tvb, offset), &next_offset,
FALSE);
if (linelen < 0)
return -1;
/*
* Get a buffer that refers to the line.
*/
line = tvb_get_ptr(tvb, offset, linelen);
lineend = line + linelen;
/*
* OK, does it look like an RTSP request or response?
*/
is_request_or_reply = is_rtsp_request_or_reply(line, linelen,
&rtsp_type);
if (is_request_or_reply)
goto is_rtsp;
/*
* No. Does it look like a blank line (as would appear
* at the end of an RTSP request)?
*/
if (linelen == 0)
goto is_rtsp; /* Yes. */
/*
* No. Does it look like a header?
*/
linep = line;
while (linep < lineend) {
c = *linep++;
if (!isprint(c))
break; /* not printable, not a MIME header */
switch (c) {
case '(':
case ')':
case '<':
case '>':
case '@':
case ',':
case ';':
case '\\':
case '"':
case '/':
case '[':
case ']':
case '?':
case '=':
case '{':
case '}':
/*
* It's a tspecial, so it's not
* part of a token, so it's not
* a field name for the beginning
* of a MIME header.
*/
goto not_rtsp;
case ':':
/*
* This ends the token; we consider
* this to be a MIME header.
*/
is_mime_header = TRUE;
goto is_rtsp;
case ' ':
case '\t':
/*
* LWS (RFC-2616, 4.2); continue the previous
* header.
*/
goto is_rtsp;
}
}
/*
* We haven't seen the colon, but everything else looks
* OK for a header line.
*
* If we've already seen an RTSP request or response
* line, or a header line, and we're at the end of
* the tvbuff, we assume this is an incomplete header
* line. (We quit this loop after seeing a blank line,
* so if we've seen a request or response line, or a
* header line, this is probably more of the request
* or response we're presumably seeing. There is some
* risk of false positives, but the same applies for
* full request or response lines or header lines,
* although that's less likely.)
*
* We throw an exception in that case, by checking for
* the existence of the next byte after the last one
* in the line. If it exists, "tvb_ensure_bytes_exist()"
* throws no exception, and we fall through to the
* "not RTSP" case. If it doesn't exist,
* "tvb_ensure_bytes_exist()" will throw the appropriate
* exception.
*/
if (saw_req_resp_or_header)
tvb_ensure_bytes_exist(tvb, offset, linelen + 1);
not_rtsp:
/*
* We don't consider this part of an RTSP request or
* reply, so we don't display it.
*/
break;
is_rtsp:
/*
* Process this line.
*/
if (linelen == 0) {
/*
* This is a blank line, which means that
* whatever follows it isn't part of this
* request or reply.
*/
proto_tree_add_text(rtsp_tree, tvb, offset,
next_offset - offset, "%s",
tvb_format_text(tvb, offset, next_offset - offset));
offset = next_offset;
break;
}
/*
* Not a blank line - either a request, a reply, or a header
* line.
*/
saw_req_resp_or_header = TRUE;
if (rtsp_tree) {
switch (rtsp_type) {
case RTSP_REQUEST:
process_rtsp_request(tvb, offset, line, linelen,
rtsp_tree);
break;
case RTSP_REPLY:
process_rtsp_reply(tvb, offset, line, linelen,
rtsp_tree);
break;
case NOT_RTSP:
break;
}
proto_tree_add_text(rtsp_tree, tvb, offset,
next_offset - offset, "%s",
tvb_format_text(tvb, offset, next_offset - offset));
}
if (is_mime_header) {
/*
* Process some MIME headers specially.
*/
#define MIME_HDR_MATCHES(header) \
(linelen > STRLEN_CONST(header) && \
strncasecmp(line, (header), STRLEN_CONST(header)) == 0)
if (MIME_HDR_MATCHES(rtsp_transport)) {
/*
* Based on the port numbers specified
* in the Transport: header, set up
* a conversation that will be dissected
* with the appropriate dissector.
*/
rtsp_create_conversation(pinfo, line, linelen);
} else if (MIME_HDR_MATCHES(rtsp_content_type)) {
/*
* If the Content-Type: header says this
* is SDP, dissect the payload as SDP.
*
* XXX - we should just do the same
* sort of header processing
* that HTTP does, and use the
* "media_type" dissector table on
* the content type.
*
* We should use those for Transport:
* and Content-Length: as well (and
* should process Content-Length: in
* HTTP).
*/
if (is_content_sdp(line, linelen))
is_sdp = TRUE;
} else if (MIME_HDR_MATCHES(rtsp_content_length)) {
/*
* Only the amount specified by the
* Content-Length: header should be treated
* as payload.
*/
content_length = rtsp_get_content_length(line,
linelen);
}
}
offset = next_offset;
}
/*
* If a content length was supplied, the amount of data to be
* processed as RTSP payload is the minimum of the content
* length and the amount of data remaining in the frame.
*
* If no content length was supplied (or if a bad content length
* was supplied), the amount of data to be processed is the amount
* of data remaining in the frame.
*/
datalen = tvb_length_remaining(tvb, offset);
reported_datalen = tvb_reported_length_remaining(tvb, offset);
if (content_length != -1) {
/*
* Content length specified; display only that amount
* as payload.
*/
if (datalen > content_length)
datalen = content_length;
/*
* XXX - limit the reported length in the tvbuff we'll
* hand to a subdissector to be no greater than the
* content length.
*
* We really need both unreassembled and "how long it'd
* be if it were reassembled" lengths for tvbuffs, so
* that we throw the appropriate exceptions for
* "not enough data captured" (running past the length),
* "packet needed reassembly" (within the length but
* running past the unreassembled length), and
* "packet is malformed" (running past the reassembled
* length).
*/
if (reported_datalen > content_length)
reported_datalen = content_length;
} else {
/*
* No content length specified; if this message doesn't
* have a body if no content length is specified, process
* nothing as payload.
*/
if (body_requires_content_len)
datalen = 0;
}
if (datalen > 0) {
/*
* There's stuff left over; process it.
*/
if (is_sdp) {
tvbuff_t *new_tvb;
/*
* Fix up the top-level item so that it doesn't
* include the SDP stuff.
*/
if (ti != NULL)
proto_item_set_len(ti, offset);
/*
* Now create a tvbuff for the SDP stuff and
* dissect it.
*
* The amount of data to be processed that's
* available in the tvbuff is "datalen", which
* is the minimum of the amount of data left in
* the tvbuff and any specified content length.
*
* The amount of data to be processed that's in
* this frame, regardless of whether it was
* captured or not, is "reported_datalen",
* which, if no content length was specified,
* is -1, i.e. "to the end of the frame.
*/
new_tvb = tvb_new_subset(tvb, offset, datalen,
reported_datalen);
call_dissector(sdp_handle, new_tvb, pinfo, tree);
} else {
if (tvb_get_guint8(tvb, offset) == RTSP_FRAMEHDR) {
/*
* This is interleaved stuff; don't
* treat it as raw data - set "datalen"
* to 0, so we won't skip the offset
* past it, which will cause our
* caller to process that stuff itself.
*/
datalen = 0;
} else {
proto_tree_add_text(rtsp_tree, tvb, offset,
datalen, "Data (%d bytes)",
reported_datalen);
}
}
/*
* We've processed "datalen" bytes worth of data
* (which may be no data at all); advance the
* offset past whatever data we've processed.
*/
offset += datalen;
}
return offset - orig_offset;
}
static void
process_rtsp_request(tvbuff_t *tvb, int offset, const guchar *data,
size_t linelen, proto_tree *tree)
{
const guchar *lineend = data + linelen;
unsigned ii;
const guchar *url;
const guchar *url_start;
guchar *tmp_url;
/* Request Methods */
for (ii = 0; ii < RTSP_NMETHODS; ii++) {
size_t len = strlen(rtsp_methods[ii]);
if (linelen >= len && !strncasecmp(rtsp_methods[ii], data, len))
break;
}
if (ii == RTSP_NMETHODS) {
/*
* We got here because "is_rtsp_request_or_reply()" returned
* RTSP_REQUEST, so we know one of the request methods
* matched, so we "can't get here".
*/
g_assert_not_reached();
}
/* Method name */
proto_tree_add_string_hidden(tree, hf_rtsp_method, tvb, offset,
strlen(rtsp_methods[ii]), rtsp_methods[ii]);
/* URL */
url = data;
while (url < lineend && !isspace(*url))
url++;
while (url < lineend && isspace(*url))
url++;
url_start = url;
while (url < lineend && !isspace(*url))
url++;
tmp_url = g_malloc(url - url_start + 1);
memcpy(tmp_url, url_start, url - url_start);
tmp_url[url - url_start] = 0;
proto_tree_add_string_hidden(tree, hf_rtsp_url, tvb,
offset + (url_start - data), url - url_start, tmp_url);
g_free(tmp_url);
}
static void
process_rtsp_reply(tvbuff_t *tvb, int offset, const guchar *data,
size_t linelen, proto_tree *tree)
{
const guchar *lineend = data + linelen;
const guchar *status = data;
const guchar *status_start;
unsigned int status_i;
/* status code */
while (status < lineend && !isspace(*status))
status++;
while (status < lineend && isspace(*status))
status++;
status_start = status;
status_i = 0;
while (status < lineend && isdigit(*status))
status_i = status_i * 10 + *status++ - '0';
proto_tree_add_uint_hidden(tree, hf_rtsp_status, tvb,
offset + (status_start - data),
status - status_start, status_i);
}
static void
dissect_rtsp(tvbuff_t *tvb, packet_info *pinfo, proto_tree *tree)
{
int offset = 0;
int len;
while (tvb_reported_length_remaining(tvb, offset) != 0) {
len = (tvb_get_guint8(tvb, offset) == RTSP_FRAMEHDR)
? dissect_rtspinterleaved(tvb, offset, pinfo, tree)
: dissect_rtspmessage(tvb, offset, pinfo, tree);
if (len == -1)
break;
offset += len;
/*
* OK, we've set the Protocol and Info columns for the
* first RTSP message; make the columns non-writable,
* so that we don't change it for subsequent RTSP messages.
*/
col_set_writable(pinfo->cinfo, FALSE);
}
}
static void
rtsp_init(void)
{
/* Routine to initialize rtsp protocol before each capture or filter pass. */
/* Release any memory if needed. Then setup the memory chunks. */
if (rtsp_vals)
g_mem_chunk_destroy(rtsp_vals);
rtsp_vals = g_mem_chunk_new("rtsp_vals",
sizeof(rtsp_conversation_data_t),
rtsp_hash_init_count * sizeof(rtsp_conversation_data_t),
G_ALLOC_AND_FREE);
}
void
proto_register_rtsp(void)
{
static gint *ett[] = {
&ett_rtspframe,
&ett_rtsp,
};
static hf_register_info hf[] = {
{ &hf_rtsp_method,
{ "Method", "rtsp.method", FT_STRING, BASE_NONE, NULL, 0, "", HFILL }},
{ &hf_rtsp_url,
{ "URL", "rtsp.url", FT_STRING, BASE_NONE, NULL, 0, "", HFILL }},
{ &hf_rtsp_status,
{ "Status", "rtsp.status", FT_UINT32, BASE_DEC, NULL, 0, "", HFILL }},
};
module_t *rtsp_module;
proto_rtsp = proto_register_protocol("Real Time Streaming Protocol",
"RTSP", "rtsp");
proto_register_field_array(proto_rtsp, hf, array_length(hf));
proto_register_subtree_array(ett, array_length(ett));
/* Register our configuration options, particularly our ports */
rtsp_module = prefs_register_protocol(proto_rtsp, proto_reg_handoff_rtsp);
prefs_register_uint_preference(rtsp_module, "tcp.port",
"RTSP TCP Port",
"Set the TCP port for RTSP messages",
10, &global_rtsp_tcp_port);
prefs_register_uint_preference(rtsp_module, "tcp.alternate_port",
"Alternate RTSP TCP Port",
"Set the alternate TCP port for RTSP messages",
10, &global_rtsp_tcp_alternate_port);
prefs_register_bool_preference(rtsp_module, "desegment_headers",
"Desegment all RTSP headers spanning multiple TCP segments",
"Whether the RTSP dissector should desegment all headers "
"of a request spanning multiple TCP segments",
&rtsp_desegment_headers);
prefs_register_bool_preference(rtsp_module, "desegment_body",
"Trust the \"Content-length:\" header and desegment RTSP "
"bodies spanning multiple TCP segments",
"Whether the RTSP dissector should use the "
"\"Content-length:\" value to desegment the body "
"of a request spanning multiple TCP segments",
&rtsp_desegment_body);
register_init_routine(rtsp_init); /* register re-init routine */
}
void
proto_reg_handoff_rtsp(void)
{
dissector_handle_t rtsp_handle;
static int rtsp_prefs_initialized = FALSE;
rtsp_handle = create_dissector_handle(dissect_rtsp, proto_rtsp);
if (!rtsp_prefs_initialized) {
rtsp_prefs_initialized = TRUE;
}
else {
dissector_delete("tcp.port", tcp_port, rtsp_handle);
dissector_delete("tcp.port", tcp_alternate_port, rtsp_handle);
}
/* Set our port number for future use */
tcp_port = global_rtsp_tcp_port;
tcp_alternate_port = global_rtsp_tcp_alternate_port;
dissector_add("tcp.port", tcp_port, rtsp_handle);
dissector_add("tcp.port", tcp_alternate_port, rtsp_handle);
sdp_handle = find_dissector("sdp");
rtp_handle = find_dissector("rtp");
rtcp_handle = find_dissector("rtcp");
}
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