Update libsrtp to upstream 1.5.0

srtp/README

 Secure RTP (SRTP) Reference Implementation
 David A. McGrew
 Cisco Systems, Inc.
 mcgrew@cisco.com
 
 
 This package provides an implementation of the Secure Real-time
 Transport Protocol (SRTP), the Universal Security Transform (UST), and
 a supporting cryptographic kernel.  These mechanisms are documented in
 the Internet Drafts in the doc/ subdirectory.  The SRTP API is
 documented in include/srtp.h, and the library is in libsrtp.a (after
 compilation).  An overview and reference manual is available in
 doc/libsrtp.pdf.  The PDF documentation is more up to date than this
 file.
 
 
 Installation:
 
 ./configure [ options ]       # GNU autoconf script 
 make                          # or gmake if needed; use GNU make
 
 The configure script accepts the following options:
 
    --help              provides a usage summary
    --disable-debug     compile without the runtime debugging system
    --enable-syslog     use syslog for error reporting
    --disable-stdout    use stdout for error reporting
    --enable-console    use /dev/console for error reporting
+   --enable-openssl    use OpenSSL crypto primitives
    --gdoi              use GDOI key management (disabled at present)
 
-By default, debbuging is enabled and stdout is used for debugging.
+By default, debugging is enabled and stdout is used for debugging.
 You can use the above configure options to have the debugging output
 sent to syslog or the system console.  Alternatively, you can define
 ERR_REPORTING_FILE in include/conf.h to be any other file that can be
 opened by libSRTP, and debug messages will be sent to it.  
 
 This package has been tested on Mac OS X (powerpc-apple-darwin1.4),
 Cygwin (i686-pc-cygwin), and Sparc (sparc-sun-solaris2.6).  Previous
 versions have been tested on Linux and OpenBSD on both x86 and sparc
 platforms.
 
@@ skipping 28 matching lines @@
   roc_driver    extended sequence number functions 
   replay_driver replay database (n.b. not used in libsrtp)
   cipher_driver ciphers 
   auth_driver   hash functions 
 
   The app rtpw is a simple rtp application which reads words from
   /usr/dict/words and then sends them out one at a time using [s]rtp.
   Manual srtp keying uses the -k option; automated key management
   using gdoi will be added later.
 
-usage: rtpw [-d <debug>]* [-k <key> [-a][-e]] [-s | -r] dest_ip dest_port
+usage: rtpw [-d <debug>]* [-k <key> [-a][-e <key size>][-g]] [-s | -r] dest_ip dest_port
 or     rtpw -l
 
   Either the -s (sender) or -r (receiver) option must be chosen.
 
   The values dest_ip, dest_port are the ip address and udp port to
   which the dictionary will be sent, respectively.  
 
   options:
 
   -s            (s)rtp sender - causes app to send words
 
-  -r            (s)rtp receive - causes app to receve words
+  -r            (s)rtp receive - causes app to receive words
 
   -k <key>      use srtp master key <key>, where the
                 key is a hexadecimal value (without the
                 leading "0x")
 
-  -e            encrypt/decrypt (for data confidentiality)
+  -e <keysize>  encrypt/decrypt (for data confidentiality)
                 (requires use of -k option as well)
+                (use 128, 192, or 256 for keysize)
+
+  -g            use AES-GCM mode (must be used with -e) 
 
   -a            message authentication 
                 (requires use of -k option as well)
 
   -l            list debug modules
 
   -d <debug>    turn on debugging for module <debug>
+  -i            specify input/output file 
+                (instead of using dictionary file)
 
 
 In order to get random 30-byte values for use as key/salt pairs , you
 can use the following bash function to format the output of
 /dev/random (where that device is available).
 
 function randhex() {
    cat /dev/random | od --read-bytes=32 --width=32 -x | awk '{ print $2 $3 $4 $5 $6 $7 $8 $9 $10 $11 $12 $13 $14 $15 $16 }'
 }
 
 
 An example of an SRTP session using two rtpw programs follows:
 
 set k=c1eec3717da76195bb878578790af71c4ee9f859e197a414a78d5abc7451
 
-[sh1]$ test/rtpw -s -k $k -ea 0.0.0.0 9999 
+[sh1]$ test/rtpw -s -k $k -e 128 -a 0.0.0.0 9999 
 Security services: confidentiality message authentication
 set master key/salt to C1EEC3717DA76195BB878578790AF71C/4EE9F859E197A414A78D5ABC7451
 setting SSRC to 2078917053
 sending word: A
 sending word: a
 sending word: aa
 sending word: aal
 ...
 
-[sh2]$ test/rtpw -r -k $k -ea 0.0.0.0 9999 
+[sh2]$ test/rtpw -r -k $k -e 128 -a 0.0.0.0 9999 
 security services: confidentiality message authentication
 set master key/salt to C1EEC3717DA76195BB878578790AF71C/4EE9F859E197A414A78D5ABC7451
 19 octets received from SSRC 2078917053 word: A
 19 octets received from SSRC 2078917053 word: a
 20 octets received from SSRC 2078917053 word: aa
 21 octets received from SSRC 2078917053 word: aal
 ...
 
 Implementation Notes
 
@@ skipping 22 matching lines @@
     sequence number in a random place, and the SRTP layer just jumps
     forward to that number at its first invocation.  An earlier
     version of this library used initial sequence numbers that are
     less than 32,768; this trick is no longer required as the
     rdbx_estimate_index(...) function has been made smarter.
 
   * The replay window is 128 bits in length, and is hard-coded to this
     value for now.