/*****************************************************************************
* sap.c : SAP announce handler
*****************************************************************************
* Copyright (C) 2002-2007 the VideoLAN team
* $Id$
*
* Authors: Clément Stenac <zorglub@videolan.org>
* Rémi Denis-Courmont <rem # videolan.org>
*
* 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., 51 Franklin Street, Fifth Floor, Boston MA 02110-1301, USA.
*****************************************************************************/
/*****************************************************************************
* Preamble
*****************************************************************************/
#ifdef HAVE_CONFIG_H
# include "config.h"
#endif
#include "vlc_common.h"
#include <stdlib.h> /* free() */
#include <stdio.h> /* sprintf() */
#include <string.h>
#include <ctype.h> /* tolower(), isxdigit() */
#include <assert.h>
#include "vlc_sout.h"
#include "vlc_network.h"
#include "vlc_charset.h"
#include "stream_output.h"
#include "libvlc.h"
/* SAP is always on that port */
#define SAP_PORT 9875
#define DEFAULT_PORT "1234"
#undef EXTRA_DEBUG
/* SAP Specific structures */
/* 100ms */
#define SAP_IDLE ((mtime_t)(0.100*CLOCK_FREQ))
#define SAP_MAX_BUFFER 65534
#define MIN_INTERVAL 2
#define MAX_INTERVAL 300
/* A SAP announce address. For each of these, we run the
* control flow algorithm */
struct sap_address_t
{
char *psz_address;
struct sockaddr_storage orig;
socklen_t origlen;
int i_rfd; /* Read socket */
int i_wfd; /* Write socket */
/* Used for flow control */
mtime_t t1;
bool b_enabled;
bool b_ready;
int i_interval;
int i_buff;
int i_limit;
};
/* A SAP session descriptor, enqueued in the SAP handler queue */
struct sap_session_t {
uint8_t *psz_data;
unsigned i_length;
sap_address_t *p_address;
session_descriptor_t *p_sd;
/* Last and next send */
mtime_t i_last;
mtime_t i_next;
};
/*****************************************************************************
* Local prototypes
*****************************************************************************/
static void * RunThread( vlc_object_t *p_this);
static int ComputeRate( sap_address_t *p_address );
static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
sap_session_t *p_session );
static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
session_descriptor_t *p_session );
static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
session_descriptor_t *p_session );
static void announce_SAPHandlerDestructor( vlc_object_t *p_this );
/**
* Create the SAP handler
*
* \param p_announce the parent announce_handler
* \return the newly created SAP handler or NULL on error
*/
sap_handler_t *announce_SAPHandlerCreate( announce_handler_t *p_announce )
{
sap_handler_t *p_sap;
p_sap = vlc_custom_create( VLC_OBJECT(p_announce), sizeof( sap_handler_t ),
VLC_OBJECT_ANNOUNCE, "announce" );
if( !p_sap )
return NULL;
p_sap->psz_object_name = strdup( "sap announcer" );
p_sap->pf_add = announce_SAPAnnounceAdd;
p_sap->pf_del = announce_SAPAnnounceDel;
p_sap->i_sessions = 0;
p_sap->i_addresses = 0;
p_sap->i_current_session = 0;
p_sap->b_control = config_GetInt( p_sap, "sap-flow-control");
if( vlc_thread_create( p_sap, "sap handler", RunThread,
VLC_THREAD_PRIORITY_LOW, false ) )
{
msg_Dbg( p_announce, "unable to spawn SAP handler thread");
vlc_object_release( p_sap );
return NULL;
}
vlc_object_set_destructor( p_sap, announce_SAPHandlerDestructor );
msg_Dbg( p_announce, "thread created, %i sessions", p_sap->i_sessions);
return p_sap;
}
static void announce_SAPHandlerDestructor( vlc_object_t * p_this )
{
sap_handler_t *p_sap = (sap_handler_t *)p_this;
int i;
/* Free the remaining sessions */
for( i = 0 ; i< p_sap->i_sessions ; i++)
{
sap_session_t *p_session = p_sap->pp_sessions[i];
FREENULL( p_session->psz_data );
REMOVE_ELEM( p_sap->pp_sessions, p_sap->i_sessions , i );
FREENULL( p_session );
}
/* Free the remaining addresses */
for( i = 0 ; i< p_sap->i_addresses ; i++)
{
sap_address_t *p_address = p_sap->pp_addresses[i];
FREENULL( p_address->psz_address );
if( p_address->i_rfd > -1 )
{
net_Close( p_address->i_rfd );
}
if( p_address->i_wfd > -1 && p_sap->b_control )
{
net_Close( p_address->i_wfd );
}
REMOVE_ELEM( p_sap->pp_addresses, p_sap->i_addresses, i );
FREENULL( p_address );
}
}
/**
* main SAP handler thread
* \param p_this the SAP Handler object
* \return nothing
*/
static void * RunThread( vlc_object_t *p_this)
{
sap_handler_t *p_sap = (sap_handler_t*)p_this;
sap_session_t *p_session;
while( !p_sap->b_die )
{
int i;
msleep( SAP_IDLE );
/* If needed, get the rate info */
if( p_sap->b_control == true )
{
for( i = 0 ; i< p_sap->i_addresses ; i++)
{
if( p_sap->pp_addresses[i]->b_enabled == true )
{
ComputeRate( p_sap->pp_addresses[i] );
}
}
}
/* Find the session to announce */
vlc_object_lock( p_sap );
if( p_sap->i_sessions > p_sap->i_current_session + 1)
{
p_sap->i_current_session++;
}
else if( p_sap->i_sessions > 0)
{
p_sap->i_current_session = 0;
}
else
{
vlc_object_unlock( p_sap );
continue;
}
p_session = p_sap->pp_sessions[p_sap->i_current_session];
/* And announce it */
if( p_session->p_address->b_enabled == true &&
p_session->p_address->b_ready == true )
{
announce_SendSAPAnnounce( p_sap, p_session );
}
vlc_object_unlock( p_sap );
}
return NULL;
}
/* Add a SAP announce */
static int announce_SAPAnnounceAdd( sap_handler_t *p_sap,
session_descriptor_t *p_session )
{
int i;
char psz_addr[NI_MAXNUMERICHOST];
bool b_ipv6 = false, b_ssm = false;
sap_session_t *p_sap_session;
mtime_t i_hash;
struct sockaddr_storage addr;
socklen_t addrlen;
vlc_object_lock( p_sap );
addrlen = p_session->addrlen;
if ((addrlen == 0) || (addrlen > sizeof (addr)))
{
vlc_object_unlock( p_sap );
msg_Err( p_sap, "No/invalid address specified for SAP announce" );
return VLC_EGENERIC;
}
/* Determine SAP multicast address automatically */
memcpy (&addr, &p_session->addr, addrlen);
switch( p_session->addr.ss_family )
{
#if defined (HAVE_INET_PTON) || defined (WIN32)
case AF_INET6:
{
/* See RFC3513 for list of valid IPv6 scopes */
struct in6_addr *a6 = &((struct sockaddr_in6 *)&addr)->sin6_addr;
memcpy( a6->s6_addr + 2, "\x00\x00\x00\x00\x00\x00"
"\x00\x00\x00\x00\x00\x02\x7f\xfe", 14 );
if( IN6_IS_ADDR_MULTICAST( a6 ) )
{
/* SSM <=> ff3x::/32 */
b_ssm = (U32_AT (a6->s6_addr) & 0xfff0ffff) == 0xff300000;
/* force flags to zero, preserve scope */
a6->s6_addr[1] &= 0xf;
}
else
/* Unicast IPv6 - assume global scope */
memcpy( a6->s6_addr, "\xff\x0e", 2 );
b_ipv6 = true;
break;
}
#endif
case AF_INET:
{
/* See RFC2365 for IPv4 scopes */
uint32_t ipv4;
ipv4 = ntohl( ((struct sockaddr_in *)&addr)->sin_addr.s_addr );
/* 224.0.0.0/24 => 224.0.0.255 */
if ((ipv4 & 0xffffff00) == 0xe0000000)
ipv4 = 0xe00000ff;
else
/* 239.255.0.0/16 => 239.255.255.255 */
if ((ipv4 & 0xffff0000) == 0xefff0000)
ipv4 = 0xefffffff;
else
/* 239.192.0.0/14 => 239.195.255.255 */
if ((ipv4 & 0xfffc0000) == 0xefc00000)
ipv4 = 0xefc3ffff;
else
if ((ipv4 & 0xff000000) == 0xef000000)
ipv4 = 0;
else
/* other addresses => 224.2.127.254 */
{
/* SSM: 232.0.0.0/8 */
b_ssm = (ipv4 >> 24) == 232;
ipv4 = 0xe0027ffe;
}
if( ipv4 == 0 )
{
msg_Err( p_sap, "Out-of-scope multicast address "
"not supported by SAP" );
vlc_object_unlock( p_sap );
return VLC_EGENERIC;
}
((struct sockaddr_in *)&addr)->sin_addr.s_addr = htonl( ipv4 );
break;
}
default:
vlc_object_unlock( p_sap );
msg_Err( p_sap, "Address family %d not supported by SAP",
addr.ss_family );
return VLC_EGENERIC;
}
i = vlc_getnameinfo( (struct sockaddr *)&addr, addrlen,
psz_addr, sizeof( psz_addr ), NULL, NI_NUMERICHOST );
if( i )
{
vlc_object_unlock( p_sap );
msg_Err( p_sap, "%s", vlc_gai_strerror( i ) );
return VLC_EGENERIC;
}
msg_Dbg( p_sap, "using SAP address: %s", psz_addr);
/* XXX: Check for dupes */
p_sap_session = (sap_session_t*)malloc(sizeof(sap_session_t));
p_sap_session->p_sd = p_session;
p_sap_session->p_address = NULL;
/* Add the address to the buffer */
for( i = 0; i < p_sap->i_addresses; i++)
{
if( !strcmp( psz_addr, p_sap->pp_addresses[i]->psz_address ) )
{
p_sap_session->p_address = p_sap->pp_addresses[i];
break;
}
}
if( p_sap_session->p_address == NULL )
{
sap_address_t *p_address = (sap_address_t *)
malloc( sizeof(sap_address_t) );
if( !p_address )
{
vlc_object_unlock( p_sap );
return VLC_ENOMEM;
}
p_address->psz_address = strdup( psz_addr );
p_address->i_wfd = net_ConnectUDP( VLC_OBJECT(p_sap), psz_addr, SAP_PORT, 255 );
if( p_address->i_wfd != -1 )
{
shutdown( p_address->i_wfd, SHUT_RD );
p_address->origlen = sizeof (p_address->orig);
getsockname (p_address->i_wfd, (struct sockaddr *)&p_address->orig,
&p_address->origlen);
}
if( p_sap->b_control == true )
{
p_address->i_rfd = net_ListenUDP1( (vlc_object_t*)p_sap, psz_addr, SAP_PORT );
if( p_address->i_rfd != -1 )
shutdown( p_address->i_rfd, SHUT_WR );
p_address->i_buff = 0;
p_address->b_enabled = true;
p_address->b_ready = false;
p_address->i_limit = 10000; /* 10000 bps */
p_address->t1 = 0;
}
else
{
p_address->b_enabled = true;
p_address->b_ready = true;
p_address->i_interval = config_GetInt( p_sap,"sap-interval");
p_address->i_rfd = -1;
}
if( p_address->i_wfd == -1 || (p_address->i_rfd == -1
&& p_sap->b_control ) )
{
msg_Warn( p_sap, "disabling address" );
p_address->b_enabled = false;
}
INSERT_ELEM( p_sap->pp_addresses,
p_sap->i_addresses,
p_sap->i_addresses,
p_address );
p_sap_session->p_address = p_address;
}
memcpy (&p_session->orig, &p_sap_session->p_address->orig,
p_session->origlen = p_sap_session->p_address->origlen);
size_t headsize = 20;
switch (p_session->orig.ss_family)
{
#ifdef AF_INET6
case AF_INET6:
headsize += 16;
break;
#endif
case AF_INET:
headsize += 4;
break;
default:
msg_Err( p_sap, "Address family %d not supported by SAP",
addr.ss_family );
vlc_object_unlock( p_sap );
return VLC_EGENERIC;
}
/* If needed, build the SDP */
assert( p_session->psz_sdp != NULL );
p_sap_session->i_last = 0;
p_sap_session->i_length = headsize + strlen (p_session->psz_sdp);
p_sap_session->psz_data = malloc (p_sap_session->i_length + 1);
if (p_sap_session->psz_data == NULL)
{
free (p_session->psz_sdp);
vlc_object_unlock( p_sap );
return VLC_ENOMEM;
}
/* Build the SAP Headers */
uint8_t *psz_head = p_sap_session->psz_data;
/* SAPv1, not encrypted, not compressed */
psz_head[0] = 0x20;
psz_head[1] = 0x00; /* No authentification length */
i_hash = mdate();
psz_head[2] = i_hash >> 8; /* Msg id hash */
psz_head[3] = i_hash; /* Msg id hash 2 */
headsize = 4;
switch (p_session->orig.ss_family)
{
#ifdef AF_INET6
case AF_INET6:
{
struct in6_addr *a6 =
&((struct sockaddr_in6 *)&p_session->orig)->sin6_addr;
memcpy (psz_head + headsize, a6, 16);
psz_head[0] |= 0x10; /* IPv6 flag */
headsize += 16;
break;
}
#endif
case AF_INET:
{
uint32_t ipv4 =
(((struct sockaddr_in *)&p_session->orig)->sin_addr.s_addr);
memcpy (psz_head + headsize, &ipv4, 4);
headsize += 4;
break;
}
}
memcpy (psz_head + headsize, "application/sdp", 16);
headsize += 16;
/* Build the final message */
strcpy( (char *)psz_head + headsize, p_session->psz_sdp);
/* Enqueue the announce */
INSERT_ELEM( p_sap->pp_sessions,
p_sap->i_sessions,
p_sap->i_sessions,
p_sap_session );
msg_Dbg( p_sap,"%i addresses, %i sessions",
p_sap->i_addresses,p_sap->i_sessions);
vlc_object_unlock( p_sap );
return VLC_SUCCESS;
}
/* Remove a SAP Announce */
static int announce_SAPAnnounceDel( sap_handler_t *p_sap,
session_descriptor_t *p_session )
{
int i;
vlc_object_lock( p_sap );
msg_Dbg( p_sap, "removing session %p from SAP", p_session);
/* Dequeue the announce */
for( i = 0; i< p_sap->i_sessions; i++)
{
if( p_session == p_sap->pp_sessions[i]->p_sd )
{
free( p_session->psz_sdp );
sap_session_t *p_mysession = p_sap->pp_sessions[i];
REMOVE_ELEM( p_sap->pp_sessions,
p_sap->i_sessions,
i );
free( p_mysession->psz_data );
free( p_mysession );
break;
}
}
/* XXX: Dequeue the address too if it is not used anymore
* TODO: - address refcount
- send a SAP deletion packet */
msg_Dbg( p_sap,"%i announcements remaining", p_sap->i_sessions );
vlc_object_unlock( p_sap );
return VLC_SUCCESS;
}
static int announce_SendSAPAnnounce( sap_handler_t *p_sap,
sap_session_t *p_session )
{
int i_ret;
/* This announce has never been sent yet */
if( p_session->i_last == 0 )
{
p_session->i_next = mdate()+ p_session->p_address->i_interval*1000000;
p_session->i_last = 1;
return VLC_SUCCESS;
}
if( p_session->i_next < mdate() )
{
#ifdef EXTRA_DEBUG
msg_Dbg( p_sap, "sending announce");
#endif
i_ret = net_Write( p_sap, p_session->p_address->i_wfd, NULL,
p_session->psz_data,
p_session->i_length );
if( i_ret != (int)p_session->i_length )
{
msg_Warn( p_sap, "SAP send failed on address %s (%i %i)",
p_session->p_address->psz_address,
i_ret, p_session->i_length );
}
p_session->i_last = p_session->i_next;
p_session->i_next = p_session->i_last
+ p_session->p_address->i_interval*1000000;
}
return VLC_SUCCESS;
}
static int ComputeRate( sap_address_t *p_address )
{
uint8_t buffer[SAP_MAX_BUFFER];
ssize_t i_tot = 0;
mtime_t i_temp;
int i_rate;
if( p_address->t1 == 0 )
{
p_address->t1 = mdate();
return VLC_SUCCESS;
}
for (;;)
{
/* Might be too slow if we have huge data */
ssize_t i_read = recv( p_address->i_rfd, buffer, SAP_MAX_BUFFER, 0 );
if (i_read == -1)
break;
i_tot += i_read;
}
i_temp = mdate();
/* We calculate the rate every 5 seconds */
if( i_temp - p_address->t1 < 5000000 )
{
p_address->i_buff += i_tot;
return VLC_SUCCESS;
}
/* Bits/second */
i_rate = (int)(8*1000000*((mtime_t)p_address->i_buff + (mtime_t)i_tot ) /
(i_temp - p_address->t1 ));
p_address->i_limit = 10000;
p_address->i_interval = ((1000*i_rate / p_address->i_limit) *
(MAX_INTERVAL - MIN_INTERVAL))/1000 + MIN_INTERVAL;
if( p_address->i_interval > MAX_INTERVAL || p_address->i_interval < 0 )
{
p_address->i_interval = MAX_INTERVAL;
}
#ifdef EXTRA_DEBUG
msg_Dbg( p_sap,"%s:%i: rate=%i, interval = %i s",
p_address->psz_address,SAP_PORT, i_rate, p_address->i_interval );
#endif
p_address->b_ready = true;
p_address->t1 = i_temp;
p_address->i_buff = 0;
return VLC_SUCCESS;
}
