Replay	RnsPutSyslog
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putsyslog.pl request

   http://rns.replaytv.net/cgi-bin/2.0/putsyslog.pl

In this requst, the X-Replay-Serial-Number value is hashed and hex-encoded. Given a serial number, this value can be generated, but given just this value, returning to a serial number is basically impossible; I assume this is done for privacy, so that users can't be identified solely by the syslog message.

The serial number is hashed to generate a key; that key is used in a stream cypher similar to the one used in RDDNS (but with different constants) to encrypt a particular block of daata. An MD5hash is taken of the serial number and the encrypted block, and used as the obfuscated serial number.

#include <openssl/md5.h>                                                        
                                                                                
static unsigned char obfusc_plaintext[32] = {                                   
    0x5b, 0xaf, 0x2f, 0x8b,  0x07, 0x03, 0x5e, 0xad,                            
    0x05, 0xe3, 0x87, 0xdc,  0xbb, 0xe4, 0x5f, 0xef,                            
    0xbc, 0x8c, 0x9d, 0x01,  0xd3, 0x96, 0xeb, 0xe9,                            
    0x7f, 0x23, 0x46, 0xdb,  0xed, 0x2a, 0xd0, 0x87                             
};                                                                              
                                                                                
static void obfuscate_sn(unsigned char * source, unsigned char * dest)          
{                                                                               
    int i;                                                                      
    MD5_CTX md5ctx;                                                             
    unsigned char cyphertext[32];                                               
    unsigned long k;                                                            
                                                                                
    k = 1;                                                                      
    for (i = 0; i < strlen(source); i++)                                        
        k = k * 0x159c1 + source[i];                                            
                                                                                
    for (i = 0; i < 32; i++) {                                                  
        cyphertext[i] = obfusc_plaintext[i] ^ k;                                
        k = k * 0x17573 + 0xf750;                                               
    }                                                                           
                                                                                
    MD5_Init(&md5ctx);                                                          
    MD5_Update(&md5ctx, source, strlen(source));                                
    MD5_Update(&md5ctx, cyphertext, 32);                                        
    MD5_Final(dest, &md5ctx);                                                   
}                                                                               

The POSTed data has content-type vnd.replay.syslog. Its format is the same as the on-system SysLog.

There is no body in the response; the only purpose is to make the system log available to Replay.

-- ToddLarason - 17 Mar 2002