Encoding and decoding of Base64 in LoadRunner

Base64 Encode/decode for LoadRunner This article describes how to encode and decode strings Base64 in LoadRunner:

http://ptfrontline.wordpress.com/2009/09/30/base64-encodedecode-for-loadrunner/

Encapsulate the b64_encode_string and b64_decode_string functions in the header file:

/*
Base Encode and Decode functions for LoadRunner
==================================================
This include the file provides functions to Encode and Decode
LoadRunner variables. It ' s based on source codes found on the
Internet and have been modified to work in LoadRunner.





Created by Kim sandell/celarius-www.celarius.com
*/
Encoding lookup Table
Char base64encode_lut[] = {
' A ', ' B ', ' C ', ' D ', ' E ', ' F ', ' G ', ' H ', ' I ', ' J ', ' K ', ' L ', ' M ', ' N ', ' O ', ' P ', ' Q ',
' R ', ' S ', ' T ', ' U ', ' V ', ' W ', ' X ', ' Y ', ' Z ', ' A ', ' B ', ' C ', ' d ', ' e ', ' f ', ' g ', ' H ',
' I ', ' j ', ' K ', ' l ', ' m ', ' n ', ' o ', ' P ', ' Q ', ' R ', ' s ', ' t ', ' u ', ' V ', ' w ', ' x ', ' Y ',
' Z ', ' 0 ', ' 1 ', ' 2 ', ' 3 ', ' 4 ', ' 5 ', ' 6 ', ' 7 ', ' 8 ', ' 9 ', ' + ', '/', ' = '};





Decode lookup Table
Char base64decode_lut[] = {
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,
0, 0, 0, 62, 0, 0, 0,63,52,53,54,55,56,57,58,59,60,61, 0, 0,
0, 0, 0, 0, 0, 0, 1, 2, 3, 4, 5, 6, 7, 8, 9,10,11,12,13,14,
15,16,17,18,19,20,21,22,23,24,25, 0, 0, 0, 0, 0, 0,26,27,28,
29,30,31,32,33,34,35,36,37,38,39,40,41,42,43,44,45,46,47,48,
49,50,51, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0,};





Void Base64Encode (char *src, char *dest, int len) 
//encodes a buffer to base64 
{
 int i=0, Slen=strlen (s RC); 
 for (I=0;i<slen && i<len;i+=3,src+=3) 
 {//ENC next 4 characters 
 * (dest++) = base64encode_lut[(*SRC&0XFC) >>0x2]; 
 * (dest++) =base64encode_lut[(*src&0x3) <<0x4| ( * (src+1) &0xf0) >>0x4]; 
 * (dest++) = ((i+1) <slen)? base64encode_lut[(* (src+1) &0xf) <<0x2| ( * (src+2) &0xc0) >>0x6]: ' = '; 
 * (dest++) = ((i+2) <slen)? base64encode_lut[* (src+2) &0x3f]: ' = '; 
 } 
 *dest= '/0 ';//Append Terminator 
}





void Base64decode (char *src, char *dest, int len)
Encodes a buffer to Base64
{
int i=0, Slen=strlen (SRC);
for (i=0;i<slen&&i<len;i+=4,src+=4)
{//Store next 4 chars in VARs for faster access
Char C1=base64decode_lut[*src], c2=base64decode_lut[* (src+1)], c3=base64decode_lut[* (src+2)], c4=base64decode_lut[ * (src+3)];
Decode to 3 chars
* (dest++) = (c1&0x3f) <<0x2| (c2&0x30) >>0x4;
* (dest++) = (c3!=64)? ((C2&0XF) <<0x4| (c3&0x3c) >>0x2): '/0 ';
* (dest++) = (c4!=64)? ((c3&0x3) <<0x6|c4&0x3f): '/0 ';
}
*dest= '/0 '; Append Terminator
}



int b64_encode_string (char *source, char *lrvar)
// ----------------------------------------------------------------------------
Encodes a string to base64 format
//
Parameters:
&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;source&nbsp;&nbsp;&nbsp; Pointer to source string to encode
&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;lrvar&nbsp;&nbsp;&nbsp;&nbsp; LR variable where base64 encoded string is stored
//
Example:
//
&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;b64_encode_string ("Encode me!", "b64")
// ----------------------------------------------------------------------------
{
int dest_size;
int res;
Char *dest;
Allocate dest Buffer
Dest_size = 1 + ((strlen (source) +2)/3*4);
Dest = (char *) malloc (dest_size);
memset (dest,0,dest_size);
Encode & Save
Base64Encode (source, dest, dest_size);
Lr_save_string (dest, Lrvar);
Free Dest Buffer
res = strlen (dest);
Free (dest);
Return length of Dest string
return res;
}

int b64_decode_string (char *source, char *lrvar)
// ----------------------------------------------------------------------------
Decodes a Base64 string to plaintext
//
Parameters:
&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;source&nbsp;&nbsp;&nbsp; Pointer to source Base64 encoded string
&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;lrvar&nbsp;&nbsp;&nbsp;&nbsp; LR variable where decoded string is stored
//
Example:
//
&nbsp;&nbsp; &nbsp;&nbsp;&nbsp; &nbsp;b64_decode_string (Lr_eval_string ("{b64}"), "Plain")
// ----------------------------------------------------------------------------
{
int dest_size;
int res;
Char *dest;
Allocate dest Buffer
Dest_size = strlen (source);
Dest = (char *) malloc (dest_size);
memset (dest,0,dest_size);
Encode & Save
Base64decode (source, dest, dest_size);
Lr_save_string (dest, Lrvar);
Free Dest Buffer
res = strlen (dest);
Free (dest);
Return length of Dest string
return res;
}

The example used is as follows:

#include "base64.h"





Vuser_init ()
{
int res;





ENCODE
Lr_save_string ("ABCDEFGHIJKLMNOPQRSTUVWXYZ0123456789", "plain");
B64_encode_string (lr_eval_string ("{Plain}"), "b64str");
Lr_output_message ("Encoded:%s", lr_eval_string ("{b64str}"));





DECODE
B64_decode_string (Lr_eval_string ("{b64str}"), "plain2");
Lr_output_message ("Decoded:%s", lr_eval_string ("{plain2}"));

Verify decoded matches original plain text
res = strcmp (lr_eval_string ("{Plain}"), Lr_eval_string ("{plain2}"));
if (res==0) lr_output_message ("Decoded matches original plain text");

return 0;





}

Encoding and decoding of Base64 in LoadRunner