/*
** Command & Conquer Renegade(tm)
** Copyright 2025 Electronic Arts Inc.
**
** This program is free software: you can redistribute it and/or modify
** it under the terms of the GNU General Public License as published by
** the Free Software Foundation, either version 3 of the License, or
** (at your option) any later version.
**
** This program is distributed in the hope that it will be useful,
** but WITHOUT ANY WARRANTY; without even the implied warranty of
** MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
** GNU General Public License for more details.
**
** You should have received a copy of the GNU General Public License
** along with this program. If not, see <http://www.gnu.org/licenses/>.
*/
/***********************************************************************************************
*** C O N F I D E N T I A L --- W E S T W O O D S T U D I O S ***
***********************************************************************************************
* *
* Project Name : Command & Conquer *
* *
* $Archive:: /Commando/Library/BLOWPIPE.CPP $*
* *
* $Author:: Greg_h $*
* *
* $Modtime:: 7/22/97 11:37a $*
* *
* $Revision:: 1 $*
* *
*---------------------------------------------------------------------------------------------*
* Functions: *
* BlowPipe::Flush -- Flushes any pending data out the pipe. *
* BlowPipe::Key -- Submit a key to the blowfish pipe handler. *
* BlowPipe::Put -- Submit a block of data for encrypt/decrypt. *
* - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - - */
#include "always.h"
#include "blowpipe.h"
#include <string.h>
#include <assert.h>
/***********************************************************************************************
* BlowPipe::Flush -- Flushes any pending data out the pipe. *
* *
* If there is any pending data in the holding buffer, then this routine will force it to *
* be flushed out the end of the pipe. *
* *
* INPUT: none *
* *
* OUTPUT: Returns with the actual number of bytes output at the end final distant pipe *
* segment in the chain. *
* *
* WARNINGS: none *
* *
* HISTORY: *
* 07/03/1996 JLB : Created. *
*=============================================================================================*/
int BlowPipe::Flush(void)
{
int total = 0;
if (Counter > 0 && BF != NULL) {
total += Pipe::Put(Buffer, Counter);
}
Counter = 0;
total += Pipe::Flush();
return(total);
}
/***********************************************************************************************
* BlowPipe::Put -- Submit a block of data for encrypt/decrypt. *
* *
* This will take the data block specified and process it before passing it on to the next *
* link in the pipe chain. A key must be submitted before this routine will actually perform*
* any processing. Prior to key submission, the data is passed through unchanged. *
* *
* INPUT: source -- Pointer to the buffer that contains the data to pass through. *
* *
* length -- The length of the data in the buffer. *
* *
* OUTPUT: Returns with then actual number of bytes output at the final distant end link in *
* the pipe chain. *
* *
* WARNINGS: none *
* *
* HISTORY: *
* 07/03/1996 JLB : Created. *
*=============================================================================================*/
int BlowPipe::Put(void const * source, int slen)
{
if (source == NULL || slen < 1) {
return(Pipe::Put(source, slen));
}
/*
** If there is no blowfish engine present, then merely pass the data through
** unchanged in any way.
*/
if (BF == NULL) {
return(Pipe::Put(source, slen));
}
int total = 0;
/*
** If there is a partial block accumulated, then tag on the new data to
** this block and process it if the block is full. Proceed with the bulk
** processing if there are any left over bytes from this step. This step
** can be skipped if there are no pending bytes in the buffer.
*/
if (Counter) {
int sublen = ((int)sizeof(Buffer)-Counter < slen) ? (sizeof(Buffer)-Counter) : slen;
memmove(&Buffer[Counter], source, sublen);
Counter += sublen;
source = ((char *)source) + sublen;
slen -= sublen;
if (Counter == sizeof(Buffer)) {
if (Control == DECRYPT) {
BF->Decrypt(Buffer, sizeof(Buffer), Buffer);
} else {
BF->Encrypt(Buffer, sizeof(Buffer), Buffer);
}
total += Pipe::Put(Buffer, sizeof(Buffer));
Counter = 0;
}
}
/*
** Process the input data in blocks until there is not enough
** source data to fill a full block of data.
*/
while (slen >= sizeof(Buffer)) {
if (Control == DECRYPT) {
BF->Decrypt(source, sizeof(Buffer), Buffer);
} else {
BF->Encrypt(source, sizeof(Buffer), Buffer);
}
total += Pipe::Put(Buffer, sizeof(Buffer));
source = ((char *)source) + sizeof(Buffer);
slen -= sizeof(Buffer);
}
/*
** If there are any left over bytes, then they must be less than the size of
** the staging buffer. Store the bytes in the staging buffer for later
** processing.
*/
if (slen > 0) {
memmove(Buffer, source, slen);
Counter = slen;
}
/*
** Return with the total number of bytes flushed out to the final end of the
** pipe chain.
*/
return(total);
}
/***********************************************************************************************
* BlowPipe::Key -- Submit a key to the blowfish pipe handler. *
* *
* This routine will take the key provided and use it to process the data that passes *
* through this pipe. Prior to a key being submitted, the data passes through the pipe *
* unchanged. *
* *
* INPUT: key -- Pointer to the key data to use. *
* *
* length-- The length of the key. The key length must not be greater than 56 bytes. *
* *
* OUTPUT: none *
* *
* WARNINGS: none *
* *
* HISTORY: *
* 07/03/1996 JLB : Created. *
*=============================================================================================*/
void BlowPipe::Key(void const * key, int length)
{
/*
** Create the blowfish engine if one isn't already present.
*/
if (BF == NULL) {
BF = new BlowfishEngine;
}
assert(BF != NULL);
if (BF != NULL) {
BF->Submit_Key(key, length);
}
}