Skip to content
New issue

Have a question about this project? Sign up for a free GitHub account to open an issue and contact its maintainers and the community.

Sign up for GitHub

By clicking “Sign up for GitHub”, you agree to our terms of service and privacy statement. We’ll occasionally send you account related emails.

Already on GitHub? Sign in to your account

Jump to bottom

Add ability to use Little Endian mode. #235

Open
wants to merge 2 commits into
base: master
Choose a base branch
from
Open

Add ability to use Little Endian mode. #235

Changes from all commits
Commits
Show all changes
2 commits
Select commit Hold shift + click to select a range
14af111
Add ability to use Little Endian mode.
Apr 8, 2020
81c5869
Rename compatibility flag and remove constructor override
Apr 9, 2020
File filter

Filter by extension

Filter by extension
Conversations
Failed to load comments.
Loading
Jump to
Jump to file
Failed to load files.
Loading
Diff view
Diff view
67 changes: 54 additions & 13 deletions crypto/src/crypto/engines/BlowfishEngine.cs
View file
Open in desktop
Original file line number Diff line number Diff line change
Expand Up @@ -308,6 +308,8 @@ public sealed class BlowfishEngine

private byte[] workingKey;

private bool useLittleEndian = false;

public BlowfishEngine()
{
S0 = new uint[SBOX_SK];
Expand All @@ -317,15 +319,15 @@ public BlowfishEngine()
P = new uint[P_SZ];
}

/**
/**
* initialise a Blowfish cipher.
*
* @param forEncryption whether or not we are for encryption.
* @param parameters the parameters required to set up the cipher.
* @exception ArgumentException if the parameters argument is
* inappropriate.
*/
public void Init(
public void Init(
bool forEncryption,
ICipherParameters parameters)
{
Expand All @@ -347,6 +349,8 @@ public bool IsPartialBlockOkay
get { return false; }
}

public bool UseLittleEndian { get => useLittleEndian; set => useLittleEndian = value; }

public int ProcessBlock(
byte[] input,
int inOff,
Expand Down Expand Up @@ -505,8 +509,18 @@ private void SetKey(byte[] key)
byte[] dst,
int dstIndex)
{
uint xl = Pack.BE_To_UInt32(src, srcIndex);
uint xr = Pack.BE_To_UInt32(src, srcIndex+4);
uint xl;
uint xr;
if (useLittleEndian)
{
xl = Pack.LE_To_UInt32(src, srcIndex);
xr = Pack.LE_To_UInt32(src, srcIndex + 4);
}
else
{
xl = Pack.BE_To_UInt32(src, srcIndex);
xr = Pack.BE_To_UInt32(src, srcIndex + 4);
}

xl ^= P[0];

Expand All @@ -518,8 +532,16 @@ private void SetKey(byte[] key)

xr ^= P[ROUNDS + 1];

Pack.UInt32_To_BE(xr, dst, dstIndex);
Pack.UInt32_To_BE(xl, dst, dstIndex + 4);
if (useLittleEndian)
{
Pack.UInt32_To_LE(xr, dst, dstIndex);
Pack.UInt32_To_LE(xl, dst, dstIndex + 4);
}
else
{
Pack.UInt32_To_BE(xr, dst, dstIndex);
Pack.UInt32_To_BE(xl, dst, dstIndex + 4);
}
}

/**
Expand All @@ -533,10 +555,21 @@ private void SetKey(byte[] key)
byte[] dst,
int dstIndex)
{
uint xl = Pack.BE_To_UInt32(src, srcIndex);
uint xr = Pack.BE_To_UInt32(src, srcIndex + 4);

xl ^= P[ROUNDS + 1];
uint xl;
uint xr;

if (useLittleEndian)
{
xl = Pack.LE_To_UInt32(src, srcIndex);
xr = Pack.LE_To_UInt32(src, srcIndex + 4);
}
else
{
xl = Pack.BE_To_UInt32(src, srcIndex);
xr = Pack.BE_To_UInt32(src, srcIndex + 4);
}

xl ^= P[ROUNDS + 1];

for (int i = ROUNDS; i > 0 ; i -= 2)
{
Expand All @@ -546,8 +579,16 @@ private void SetKey(byte[] key)

xr ^= P[0];

Pack.UInt32_To_BE(xr, dst, dstIndex);
Pack.UInt32_To_BE(xl, dst, dstIndex + 4);
}
if (useLittleEndian)
{
Pack.UInt32_To_LE(xr, dst, dstIndex);
Pack.UInt32_To_LE(xl, dst, dstIndex + 4);
}
else
{
Pack.UInt32_To_BE(xr, dst, dstIndex);
Pack.UInt32_To_BE(xl, dst, dstIndex + 4);
}
}
}
}