cas_parser.c

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/*
 * The contents of this file are subject to the terms
 * of the Common Development and Distribution License
 * (the "License").  You may not use this file except
 * in compliance with the License.
 *
 * You can obtain a copy of the license at
 * http://www.opensource.org/licenses/cddl1.php
 * See the License for the specific language governing
 * permissions and limitations under the License.
 *
 * When distributing Covered Code, include this CDDL
 * HEADER in each file and include the License file at
 * http://www.opensource.org/licenses/cddl1.php.  If 
 * applicable, add the following below this CDDL HEADER, 
 * with the fields enclosed by brackets "[]" replaced 
 * with your own identifying information: 
 * Portions Copyright [yyyy]
 * [name of copyright owner]
 */ 

/*
 * $(@)cas_parser.c $Revision: 1.1.1.1 $ $Date: 2006/04/17 22:47:29 $
 * 
 * Copyright 2006 Sun Microsystems, Inc. All Rights Reserved.
 */
/*
 * Copyright (c) 2005 by Sun Microsystems, Inc.
 * Functions to perform TS parsing

 * Created:   July 29, 2005
 * Author:    Yongfang Liang
 *---------------------------------------------------------------*/
 
#include  "cas_sys.h"

static void mpeg2GatherTS(Mpeg2Ts mpeg2Ts, Pipe pipe)
{
    ca_sys_p          p_sys = (ca_sys_p)mpeg2Ts->token; 
    ca_ts_pck_p       p_ts_pkt = NULL;

    p_ts_pkt = PIPE_PEEK(pipe, ca_ts_pck_t);
    memcpy(&(p_sys->pkt_buf.data[0]), p_ts_pkt, sizeof(ca_ts_pck_t));
    return;
}

static RetCode   mpeg2PatInfoCallback (void *token, Mpeg2PatInfo *infop,
				               RetCode retCode)
{
    ca_sys_p          p_sys = (ca_sys_p)token;
    unsigned            pex;
    Mpeg2PatSection     *curPsp = &(infop->patSection);

    for (pex = 0; pex < curPsp->nPatEntries; pex++) 
    {
        Mpeg2PatEntry   *pep      = &curPsp->patEntries[pex];
        unsigned        pn        = MPEG2_PAT_ENTRY_PROGRAM_NUMBER(pep);
        unsigned        pid       = MPEG2_PAT_ENTRY_PROGRAM_MAP_PID(pep);
        p_sys->pid[pid].b_seen    = TRUE;
        p_sys->pid[pid].pn        = pn;
        p_sys->pid[pid].b_pmt_pid = TRUE;
    }
    return RETCODE_SUCCESS;
    
}

static RetCode   mpeg2GatherTSCallback (void *token, Mpeg2TsInfo *infop,
				                RetCode retCode)
{
    ca_sys_p          p_sys = (ca_sys_p)token;
    unsigned          pid;
    Pipe              pidPipe  = NULL;
    #define MPEG2_TS_GATHER_TS 7

    if ((retCode & 0xffff) == MPEG2_TS_GATHER_TS)
    {
        mpeg2GatherTS((Mpeg2Ts)token, (Pipe)infop);
        return RETCODE_SUCCESS;
    }

    pid = MPEG2_TS_TRANSPORT_PACKET_PID(&infop->transportPacket);
    pidPipe = MMP_CONTEXT_PIDTOPIPE(p_sys->mpeg2TScop, pid);

    if (p_sys->tsCallback)
    {
    	(*p_sys->tsCallback)(p_sys->ts_token, infop->position);
    }
    
    if (pidPipe != PIPE_NULL && pidPipe != NULL)
    {
    	if (pid == MPEG2_TS_NULL_PID || pid == MPEG2_TS_PAT_PID
    		|| pid == MPEG2_TS_CAT_PID)
    	{
    		/* break: output the packet as it is */
			/* output the packet  */
    		pipeSync(p_sys->outpipe);
    		pipePut(p_sys->outpipe,&(p_sys->pkt_buf.data[0]), MPEG2_TS_PKT_SIZE, FALSE, p_sys->putPosition);
			p_sys->putPosition += MPEG2_TS_PKT_SIZE;
    	}
    	else  /* pmt */
    	{
    		if (infop->transportPacket.adaptationFieldControl == MPEG2_TS_ADAPTATION_FIELD_CONTROL_ADAPTATION_ONLY 
    			|| infop->transportPacket.adaptationFieldControl == MPEG2_TS_ADAPTATION_FIELD_CONTROL_ADAPTATION_PAYLOAD)
    		{
    			/* output a new ts packet contains only adaptation field, since we will generate a new pmt */
                int i = 0;
    			/* adaptation field only */
    			p_sys->pkt_buf.data[3] |= 0x20; /* bit 4 */
    			p_sys->pkt_buf.data[3] &= 0xef; /* bit 3 */
    		    /* change adaptation field length */
    			p_sys->pkt_buf.data[4] = MPEG2_TS_PKT_SIZE - 5;
    			for (i = infop->adaptationFieldLength + 5; i < MPEG2_TS_PKT_SIZE; i++)
    			{
    			    p_sys->pkt_buf.data[i] = 0xff; /* stuffing bytes */
    			}
			    /* output this additional packet before new pmt is built */
                pipeSync(p_sys->outpipe);
			    pipePut(p_sys->outpipe,&(p_sys->pkt_buf.data[0]), MPEG2_TS_PKT_SIZE, FALSE, p_sys->putPosition);
			    p_sys->putPosition += MPEG2_TS_PKT_SIZE;
    			msg_TRACE("old PMT contains adaptation field, output one adaptation_only TS packet.\n");
    		}
    	}
    }
    else
    {
    	/* scramble the packet if required, only the payload! */
    	scrambleTsPacket(p_sys, pid, &(p_sys->pkt_buf.data[0]), &(p_sys->pkt_buf.data[0]) + MPEG2_TS_PKT_SIZE - infop->payloadLen, 
    	                 infop->payloadLen, infop->position);
	    /* output the packet  */
	    pipeSync(p_sys->outpipe);
	    pipePut(p_sys->outpipe,&(p_sys->pkt_buf.data[0]), MPEG2_TS_PKT_SIZE, FALSE, p_sys->putPosition);
	    p_sys->putPosition += MPEG2_TS_PKT_SIZE;
    }
    
    return RETCODE_SUCCESS;
}

/* callback functin for PMT */
static RetCode   mpeg2InjectCA2Pmt (void *token, Mpeg2PmtInfo *infop,
				                           RetCode retCode)
{
    ca_sys_p          p_sys = (ca_sys_p)token;
    Mpeg2PmtTsProgramMapSection *pmsp = &infop->tsProgramMapSection;

     unsigned   pcr_pid;
    Mpeg2PmtStream    *streamList = pmsp->streamList;
    Mpeg2PmtDescriptor *desc = NULL;
    unsigned            pn;  /* program number */
    encrypt_key_p p_keys = NULL;
    ts_ca_descriptor_p p_ca_descriptor = NULL; /* CA descriptors to be inserted for this pmt */
    int i = 0;
 
    pn = MPEG2_PMT_PROGRAM_NUMBER(&pmsp->psiExtension);

    /* record the pids (pcr_pid and elementary stream pid) that have been used */
    pcr_pid = MPEG2_PMT_HEADER_PCR_PID(&(pmsp->pmtHeader));
    p_sys->pid[pcr_pid].b_seen = TRUE;
    p_sys->pid[pcr_pid].pn     = pn;

    /* note: we assume there are no CA descriptors for current program
       and that is why we need to introduce them */
    for (streamList = pmsp->streamList; streamList != NULL; 
             streamList = streamList->next)
    {
        unsigned   ePid = MPEG2_PMT_STREAM_HEADER_ELEMENTARY_PID(&streamList->streamHeader);
        p_sys->pid[ePid].b_seen = TRUE;
        p_sys->pid[ePid].pn     = pn;
    }

    /* look up the keys. do we need CA injection for this PMT ? */
    for (p_keys = p_sys->p_keys; p_keys != NULL; 
             p_keys = p_keys->next)
    {
    	int key_count = 0;
        if (p_keys->pn == pn || p_keys->pn == FOR_ANY_PROGRAM)
        {
            /* create the CAs if an injection is needed */
            short availabe_pid = 0;
            int   i = 0;

            key_count ++;
            if (p_keys->ecm_pid != 0)
            {
            	/* we already got one */
            	availabe_pid = p_keys->ecm_pid;
            }
            else
            {
	            /* find available pid */
	            for (i = 0x10; i < 0x01FFE; i++)
	            {
	            	if (p_sys->pid[i].b_seen == FALSE)
	            	{
	                    availabe_pid         = (short)i;
	                    p_sys->pid[i].b_seen = TRUE;
	                    p_sys->pid[i].pn     = pn;
                        msg_TRACE("ECM pid allocated: %d,the %dth key.\n", availabe_pid, key_count);
	            		break;
	            	}
	            }
            }
            if (availabe_pid != 0)
            {
                p_sys->pid[availabe_pid].b_seen = TRUE;
                p_sys->pid[availabe_pid].pn     = pn;
                
                /* assign pid to this key */
                p_keys->ecm_pid = availabe_pid;
                
                /* we can support multiple CA system, now just CA_SYS_ID */
                /* we don't have privdate data for the descriptor */
                ts_ca_descriptor_p d = ts_ca_descriptor_create(p_keys->e_type, p_sys->i_ca_system_id, availabe_pid, NULL, 0);
                d->p_key             = p_keys;
                p_ca_descriptor      = ts_ca_descriptor_append(p_ca_descriptor, d);
            }
            else
            {
            	printf("all the pids are being used, key ignored, pn# %d\n", p_keys->pn);
            }
        }
    }

    if (p_ca_descriptor)
    {
        /* set up the encryption key for each ES */
	    for (streamList = pmsp->streamList; streamList != NULL; 
	             streamList = streamList->next)
	    {
            ts_ca_descriptor_p d = NULL;
	        short    ePid = MPEG2_PMT_STREAM_HEADER_ELEMENTARY_PID(&streamList->streamHeader);

	        for (d = p_ca_descriptor; d != NULL; d = d->next)
	        {
                /* what type of CA? for the whole program, video or audio? */
	        	switch (d->en_type)
	        	{
	        		case ENCRYPT_ALL:
                        p_sys->pid[pcr_pid].p_key = d->p_key;
                        
	        			p_sys->pid[ePid].p_key    = d->p_key;
	        			/* now we have the specific stream type */
	        			d->stream_type = ANY_STREAM_TYPE; 
	        			break;