ccRTP
rtppkt.h
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00001 // Copyright (C) 2002 Federico Montesino Pouzols <fedemp@altern.org>.
00002 //
00003 // This program is free software; you can redistribute it and/or modify
00004 // it under the terms of the GNU General Public License as published by
00005 // the Free Software Foundation; either version 2 of the License, or
00006 // (at your option) any later version.
00007 //
00008 // This program is distributed in the hope that it will be useful,
00009 // but WITHOUT ANY WARRANTY; without even the implied warranty of
00010 // MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
00011 // GNU General Public License for more details.
00012 //
00013 // You should have received a copy of the GNU General Public License
00014 // along with this program; if not, write to the Free Software
00015 // Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
00016 //
00017 // As a special exception, you may use this file as part of a free software
00018 // library without restriction.  Specifically, if other files instantiate
00019 // templates or use macros or inline functions from this file, or you compile
00020 // this file and link it with other files to produce an executable, this
00021 // file does not by itself cause the resulting executable to be covered by
00022 // the GNU General Public License.  This exception does not however
00023 // invalidate any other reasons why the executable file might be covered by
00024 // the GNU General Public License.
00025 //
00026 // This exception applies only to the code released under the name GNU
00027 // ccRTP.  If you copy code from other releases into a copy of GNU
00028 // ccRTP, as the General Public License permits, the exception does
00029 // not apply to the code that you add in this way.  To avoid misleading
00030 // anyone as to the status of such modified files, you must delete
00031 // this exception notice from them.
00032 //
00033 // If you write modifications of your own for GNU ccRTP, it is your choice
00034 // whether to permit this exception to apply to your modifications.
00035 // If you do not wish that, delete this exception notice.
00036 //
00037 
00038 #ifndef CCXX_RTP_RTPPKT_H_
00039 #define CCXX_RTP_RTPPKT_H_
00040 
00041 #include <ccrtp/base.h>
00042 #include <ccrtp/formats.h>
00043 #include <ccrtp/CryptoContext.h>
00044 
00045 #ifdef CCXX_NAMESPACES
00046 namespace ost {
00047 #endif
00048 
00073 class CryptoContext;
00074 
00075 class  __EXPORT RTPPacket
00076 {
00077 private:
00078         struct RTPFixedHeader;
00079         struct RTPHeaderExt;
00080 
00081 public:
00094         RTPPacket(const unsigned char* const block, size_t len,
00095                   bool duplicate = false);
00096 
00108         RTPPacket(size_t hdrlen, size_t plen, uint8 paddinglen, CryptoContext* pcc= NULL);
00109 
00116         inline uint32
00117         getHeaderSize() const
00118         { return hdrSize; }
00119 
00123         inline const uint8* const
00124         getPayload() const
00125         { return (uint8*)(buffer + getHeaderSize()); }
00126 
00130         inline uint32
00131         getPayloadSize() const
00132         { return payloadSize; }
00133 
00137         inline PayloadType
00138         getPayloadType() const
00139         { return static_cast<PayloadType>(getHeader()->payload); }
00140 
00144         inline uint16
00145         getSeqNum() const
00146         { return cachedSeqNum; }
00147 
00151         inline uint32
00152         getTimestamp() const
00153         { return cachedTimestamp; }
00154 
00158         inline uint8
00159         getProtocolVersion() const
00160         { return getHeader()->version; }
00161 
00166         inline bool
00167         isPadded() const
00168         { return getHeader()->padding; }
00169 
00176         inline uint8
00177         getPaddingSize() const
00178         { return buffer[total - 1]; }
00179 
00186         inline bool
00187         isMarked() const
00188         { return getHeader()->marker; }
00189 
00195         inline bool
00196         isExtended() const
00197         { return getHeader()->extension; }
00198 
00203         inline uint16
00204         getCSRCsCount() const
00205         { return getHeader()->cc; }
00206 
00214         inline const uint32*
00215         getCSRCs() const
00216         { return static_cast<const uint32*>(&(getHeader()->sources[1])); }
00217 
00230         inline uint16
00231         getHdrExtUndefined() const
00232         { return (isExtended()? getHeaderExt()->undefined : 0); }
00233 
00245         inline uint32
00246         getHdrExtSize() const
00247         { return (isExtended()?
00248                   (static_cast<uint32>(ntohs(getHeaderExt()->length)) << 2) :
00249                   0); }
00250 
00257         inline const unsigned char*
00258         getHdrExtContent() const
00259         { return (isExtended() ?
00260                   (reinterpret_cast<const unsigned char*>(getHeaderExt()) +
00261                    sizeof(RTPHeaderExt)) :
00262                   NULL); }
00263 
00270         inline const unsigned char* const
00271         getRawPacket() const
00272         { return buffer; }
00273 
00280         inline uint32
00281         getRawPacketSize() const
00282         { return total; }
00283 
00284         inline uint32
00285         getRawPacketSizeSrtp() const
00286         { return total + srtpLength; }
00287 
00288         inline size_t
00289         getSizeOfFixedHeader() const
00290         { return sizeof(RTPFixedHeader); }
00291         
00303     void reComputePayLength(bool padding);
00304     
00305 protected:
00309         inline virtual ~RTPPacket()
00310         { endPacket(); }
00311 
00315         void
00316         endPacket();
00317 
00323         inline RTPFixedHeader*
00324         getHeader() const
00325         { return reinterpret_cast<RTPFixedHeader*>(buffer); }
00326 
00327         inline void
00328         setExtension(bool e)
00329         { getHeader()->extension = e; }
00330 
00338         inline const RTPHeaderExt*
00339         getHeaderExt() const
00340         {
00341          uint32 fixsize = sizeof(RTPFixedHeader) + (getHeader()->cc << 2);
00342          return (reinterpret_cast<RTPHeaderExt*>(buffer + fixsize));
00343         }
00344 
00350         inline uint32
00351         getRawTimestamp() const
00352         { return ntohl(getHeader()->timestamp); }
00353 
00354         inline void
00355         setbuffer(const void* src, size_t len, size_t pos)
00356         { memcpy(buffer + pos,src,len); }
00357 
00359         uint16 cachedSeqNum;
00361         uint32 cachedTimestamp;
00362 
00369         uint32 srtpDataOffset;
00370 
00376         int32 srtpLength;
00377 
00379         uint32 total;
00380 
00382         uint32 payloadSize;
00383 
00384 private:
00386         unsigned char* buffer;
00388         uint32 hdrSize;
00390         bool duplicated;
00391 
00392 #ifdef  CCXX_PACKED
00393 #pragma pack(1)
00394 #endif
00395 
00405         struct RTPFixedHeader
00406         {
00407 #if     __BYTE_ORDER == __BIG_ENDIAN
00408 
00409                 unsigned char version:2;       
00410                 unsigned char padding:1;       
00411                 unsigned char extension:1;     
00412                 unsigned char cc:4;            
00413                 unsigned char marker:1;        
00414                 unsigned char payload:7;       
00415 #else
00416 
00417                 unsigned char cc:4;            
00418                 unsigned char extension:1;     
00419                 unsigned char padding:1;       
00420                 unsigned char version:2;       
00421                 unsigned char payload:7;       
00422                 unsigned char marker:1;        
00423 #endif
00424                 uint16 sequence;        
00425                 uint32 timestamp;       
00426                 uint32 sources[1];      
00427         };
00428 
00437 public:
00438         struct RFC2833Payload
00439         {
00440 #if __BYTE_ORDER == __BIG_ENDIAN
00441                 uint8 event : 8;
00442                 bool ebit : 1;
00443                 bool rbit : 1;
00444                 uint8 vol : 6;
00445                 uint16 duration : 16;
00446 #else
00447                 uint8 event : 8;
00448                 uint8 vol : 6;
00449                 bool rbit : 1;
00450                 bool ebit : 1;
00451                 uint16 duration : 16;
00452 #endif
00453         };
00454 
00455 private:
00463         struct RTPHeaderExt
00464         {
00465                 uint16 undefined; 
00466                 uint16 length;    
00467         };
00468 #ifdef  CCXX_PACKED
00469 #pragma pack()
00470 #endif
00471 
00472         /* definitions for access to most common 2833 fields... */
00473 
00474 public:
00480         inline struct RFC2833Payload *getRaw2833Payload(void)
00481                 {return (struct RFC2833Payload *)getPayload();}
00482 
00488         inline uint16 get2833Duration(void)
00489                 {return ntohs(getRaw2833Payload()->duration);}
00490 
00496         inline void set2833Duration(uint16 timestamp)
00497                 {getRaw2833Payload()->duration = htons(timestamp);}
00498 };
00499 
00510 class __EXPORT OutgoingRTPPkt : public RTPPacket
00511 {
00512 public:
00539         OutgoingRTPPkt(const uint32* const csrcs, uint16 numcsrc,
00540                        const unsigned char* const hdrext, uint32 hdrextlen,
00541                        const unsigned char* const data, size_t datalen,
00542                        uint8 paddinglen= 0, CryptoContext* pcc= NULL);
00543 
00564         OutgoingRTPPkt(const uint32* const csrcs, uint16 numcsrc,
00565                        const unsigned char* const data, size_t datalen,
00566                        uint8 paddinglen= 0, CryptoContext* pcc= NULL);
00567 
00584         OutgoingRTPPkt(const unsigned char* const data, size_t datalen,
00585                        uint8 paddinglen= 0, CryptoContext* pcc= NULL);
00586 
00587         ~OutgoingRTPPkt()
00588         { }
00589 
00593         inline void
00594         setPayloadType(PayloadType pt)
00595         { getHeader()->payload = pt; }
00596 
00602         inline void
00603         setSeqNum(uint16 seq)
00604         {
00605                 cachedSeqNum = seq;
00606                 getHeader()->sequence = htons(seq);
00607         }
00608 
00612         inline void
00613         setTimestamp(uint32 pts)
00614         {
00615                 cachedTimestamp = pts;
00616                 getHeader()->timestamp = htonl(pts);
00617         }
00618 
00625         inline void
00626         setSSRC(uint32 ssrc) const
00627         { getHeader()->sources[0] = htonl(ssrc); }
00628 
00636         inline void
00637         setSSRCNetwork(uint32 ssrc) const
00638         { getHeader()->sources[0] = ssrc; }
00639 
00647         inline void
00648         setMarker(bool mark)
00649         { getHeader()->marker = mark; }
00650 
00657         void protect(uint32 ssrc, CryptoContext* pcc);
00658 
00662         inline bool
00663         operator==(const OutgoingRTPPkt &p) const
00664         { return ( this->getSeqNum() == p.getSeqNum() ); }
00665 
00669         inline bool
00670         operator!=(const OutgoingRTPPkt &p) const
00671         { return ( this->getSeqNum() != p.getSeqNum() ); }
00672 
00673 private:
00678         OutgoingRTPPkt(const OutgoingRTPPkt &o);
00679 
00684         OutgoingRTPPkt&
00685         operator=(const OutgoingRTPPkt &o);
00686 
00691         void setCSRCArray(const uint32* const csrcs, uint16 numcsrc);
00692 
00693 };
00694 
00707 class __EXPORT IncomingRTPPkt : public RTPPacket
00708 {
00709 public:
00722         IncomingRTPPkt(const unsigned char* block, size_t len);
00723 
00724         ~IncomingRTPPkt()
00725         { }
00726 
00732         inline bool
00733         isHeaderValid()
00734         { return headerValid; }
00735 
00742         inline uint32
00743         getSSRC() const
00744         { return cachedSSRC; }
00745 
00756         int32
00757         unprotect(CryptoContext* pcc);
00758 
00763         inline bool
00764         operator==(const IncomingRTPPkt &p) const
00765         { return ( (this->getSeqNum() == p.getSeqNum()) &&
00766                    (this->getSSRC() == p.getSSRC()) ); }
00767 
00772         inline bool
00773         operator!=(const IncomingRTPPkt &p) const
00774         { return !( *this == p ); }
00775 
00776 private:
00781         IncomingRTPPkt(const IncomingRTPPkt &ip);
00782 
00787         IncomingRTPPkt&
00788         operator=(const IncomingRTPPkt &ip);
00789 
00791         bool headerValid;
00793         uint32 cachedSSRC;
00794         // Masks for RTP header validation: types matching RTCP SR or
00795         // RR must be rejected to avoid accepting misaddressed RTCP
00796         // packets.
00797         static const uint16 RTP_INVALID_PT_MASK;
00798         static const uint16 RTP_INVALID_PT_VALUE;
00799 };
00800  // rtppacket
00802 
00803 #ifdef  CCXX_NAMESPACES
00804 }
00805 #endif
00806 
00807 #endif  // ndef CCXX_RTP_RTPPKT_H_
00808