Add SIMON-64 and SIMON-128 lightweight block ciphers (GH #539)

1 files changed, 365 insertions, 0 deletions

diff --git a/simon.cpp b/simon.cpp
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+++ b/simon.cpp
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+// simon.h - written and placed in the public domain by Jeffrey Walton

+

+#include "pch.h"

+#include "config.h"

+

+#include "simon.h"

+#include "misc.h"

+

+ANONYMOUS_NAMESPACE_BEGIN

+

+using CryptoPP::word32;

+using CryptoPP::word64;

+using CryptoPP::rotlFixed;

+using CryptoPP::rotrFixed;

+

+//! \brief Round transformation helper

+//! \tparam W word type

+//! \param v value

+template <class W>

+inline W f(const W v)

+{

+    return (rotlFixed(v, 1) & rotlFixed(v, 8)) ^ rotlFixed(v, 2);

+}

+

+//! \brief Round transformation

+//! \tparam W word type

+//! \param x value

+//! \param y value

+//! \param k value

+//! \param l value

+template <class W>

+inline void R2(W& x, W& y, const W k, const W l)

+{

+    y ^= f(x); y ^= k;

+    x ^= f(y); x ^= l;

+}

+

+//! \brief Forward transformation

+//! \tparam W word type

+//! \tparam R number of rounds

+//! \param c output array

+//! \param p input array

+//! \param k subkey array

+template <class W, unsigned int R>

+inline void SIMON_Encrypt(W c[2], const W p[2], const W k[R])

+{

+    c[0]=p[0]; c[1]=p[1];

+

+    for (size_t i = 0; static_cast<int>(i) < R-1; i += 2)

+        R2(c[0], c[1], k[i], k[i + 1]);

+

+    // The constexpr residue should allow the optimizer to remove unneeded statements

+    if (R%2 == 1)

+    {

+        c[1] ^= f(c[0]); c[1] ^= k[R-1];

+        W t = c[0]; c[0] = c[1]; c[1] = t;

+    }

+}

+

+//! \brief Reverse transformation

+//! \tparam W word type

+//! \tparam R number of rounds

+//! \param p output array

+//! \param c input array

+//! \param k subkey array

+template <class W, unsigned int R>

+inline void SIMON_Decrypt(W p[2], const W c[2], const W k[R])

+{

+    p[0]=c[0]; p[1]=c[1];

+

+    // The constexpr residue should allow the optimizer to remove unneeded statements

+    if (R % 2 == 0)

+    {

+        for (size_t i = R-2; static_cast<int>(i) >= 0; i -= 2)

+            R2(p[1], p[0], k[i+1], k[i]);

+    }

+    else

+    {

+        const W t = p[1]; p[1] = p[0];

+        p[0] = t; p[1] ^= k[R-1]; p[1] ^= f(p[0]);

+

+        for (size_t i = R-3; static_cast<int>(i) >= 0; i -= 2)

+            R2(p[1], p[0], k[i+1], k[i]);

+    }

+}

+

+//! \brief Subkey generation function

+//! \details Used for SIMON-64 with 96-bit key and 42 rounds. A template was

+//!   not worthwile because all instantiations would need specialization.

+//! \param key empty subkey array

+//! \param k user key array

+inline void SPECK64_ExpandKey_42R3K(word32 key[42], const word32 k[3])

+{

+	const word32 c = 0xfffffffc;

+	word64 z = 0x7369f885192c0ef5LL;

+

+	key[0] = k[0]; key[1] = k[1]; key[2] = k[2];

+	for (size_t i = 3; i<42; ++i)

+	{

+		key[i] = c ^ (z & 1) ^ key[i-3] ^ rotrFixed(key[i-1], 3) ^ rotrFixed(key[i-1], 4);

+		z >>= 1;

+	}

+}

+

+//! \brief Subkey generation function

+//! \details Used for SIMON-64 with 128-bit key and 44 rounds. A template was

+//!   not worthwile because all instantiations would need specialization.

+//! \param key empty subkey array

+//! \param k user key array

+inline void SPECK64_ExpandKey_44R4K(word32 key[44], const word32 k[4])

+{

+	const word32 c = 0xfffffffc;

+	word64 z = W64LIT(0xfc2ce51207a635db);

+

+	key[0] = k[0]; key[1] = k[1]; key[2] = k[2]; key[3] = k[3];

+	for (size_t i = 4; i<44; ++i)

+	{

+		key[i] = c ^ (z & 1) ^ key[i-4] ^ rotrFixed(key[i-1], 3) ^ key[i-3] ^ rotrFixed(key[i-1], 4) ^ rotrFixed(key[i-3], 1);

+		z >>= 1;

+	}

+}

+

+//! \brief Subkey generation function

+//! \details Used for SIMON-128 with 128-bit key and 68 rounds. A template was

+//!   not worthwile because all instantiations would need specialization.

+//! \param key empty subkey array

+//! \param k user key array

+inline void SIMON128_ExpandKey_68R2K(word64 key[68], const word64 k[2])

+{

+    const word64 c = W64LIT(0xfffffffffffffffc);

+    word64 z = W64LIT(0x7369f885192c0ef5);

+

+    key[0] = k[0]; key[1] = k[1];

+    for (size_t i=2; i<66; ++i)

+    {

+        key[i] = c^(z&1)^key[i-2]^rotrFixed(key[i-1],3)^rotrFixed(key[i-1],4);

+        z>>=1;

+    }

+

+    key[66] = c^1^key[64]^rotrFixed(key[65],3)^rotrFixed(key[65],4);

+    key[67] = c^key[65]^rotrFixed(key[66],3)^rotrFixed(key[66],4);

+}

+

+//! \brief Subkey generation function

+//! \details Used for SIMON-128 with 192-bit key and 69 rounds. A template was

+//!   not worthwile because all instantiations would need specialization.

+//! \param key empty subkey array

+//! \param k user key array

+inline void SIMON128_ExpandKey_69R3K(word64 key[69], const word64 k[3])

+{

+    const word64 c = W64LIT(0xfffffffffffffffc);

+    word64 z = W64LIT(0xfc2ce51207a635db);

+

+    key[0]=k[0]; key[1]=k[1]; key[2]=k[2];

+    for (size_t i=3; i<67; ++i)

+    {

+        key[i] = c^(z&1)^key[i-3]^rotrFixed(key[i-1],3)^rotrFixed(key[i-1],4);

+        z>>=1;

+    }

+

+    key[67] = c^key[64]^rotrFixed(key[66],3)^rotrFixed(key[66],4);

+    key[68] = c^1^key[65]^rotrFixed(key[67],3)^rotrFixed(key[67],4);

+}

+

+//! \brief Subkey generation function

+//! \details Used for SIMON-128 with 256-bit key and 72 rounds. A template was

+//!   not worthwile because all instantiations would need specialization.

+//! \param key empty subkey array

+//! \param k user key array

+inline void SIMON128_ExpandKey_72R4K(word64 key[72], const word64 k[4])

+{

+    const word64 c = W64LIT(0xfffffffffffffffc);

+    word64 z = W64LIT(0xfdc94c3a046d678b);

+

+    key[0]=k[0]; key[1]=k[1]; key[2]=k[2]; key[3]=k[3];

+    for (size_t i=4; i<68; ++i)

+    {

+        key[i] = c^(z&1)^key[i-4]^rotrFixed(key[i-1],3)^key[i-3]^rotrFixed(key[i-1],4)^rotrFixed(key[i-3],1);

+        z>>=1;

+    }

+

+    key[68] = c^key[64]^rotrFixed(key[67],3)^key[65]^rotrFixed(key[67],4)^rotrFixed(key[65],1);

+    key[69] = c^1^key[65]^rotrFixed(key[68],3)^key[66]^rotrFixed(key[68],4)^rotrFixed(key[66],1);

+    key[70] = c^key[66]^rotrFixed(key[69],3)^key[67]^rotrFixed(key[69],4)^rotrFixed(key[67],1);

+    key[71] = c^key[67]^rotrFixed(key[70],3)^key[68]^rotrFixed(key[70],4)^rotrFixed(key[68],1);

+}

+

+ANONYMOUS_NAMESPACE_END

+

+///////////////////////////////////////////////////////////

+

+NAMESPACE_BEGIN(CryptoPP)

+

+#if 1

+void SIMON64::Base::UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params)

+{

+    CRYPTOPP_ASSERT(keyLength == 12 || keyLength == 16);

+    CRYPTOPP_UNUSED(params);

+

+    // Building the key schedule table requires {3,4} words workspace.

+    // Encrypting and decrypting requires 4 words workspace.

+    m_kwords = keyLength/sizeof(word32);

+    m_wspace.New(STDMAX(m_kwords,4U));

+

+    // Avoid GetUserKey. SIMON does unusual things with key string and word ordering

+    // {A,B} -> {B,A}, {A,B,C} -> {C,B,A}, etc.

+    typedef GetBlock<word32, BigEndian, false> InBlock;

+    InBlock iblk(userKey);

+

+    switch (m_kwords)

+    {

+    case 3:

+        m_rkey.New(42);

+        iblk(m_wspace[2])(m_wspace[1])(m_wspace[0]);

+		SPECK64_ExpandKey_42R3K(m_rkey, m_wspace);

+        break;

+    case 4:

+        m_rkey.New(44);

+        iblk(m_wspace[3])(m_wspace[2])(m_wspace[1])(m_wspace[0]);

+		SPECK64_ExpandKey_44R4K(m_rkey, m_wspace);

+        break;

+    default:

+        CRYPTOPP_ASSERT(0);;

+    }

+}

+

+void SIMON64::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const

+{

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef GetBlock<word32, BigEndian, false> InBlock;

+    InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);

+

+    switch (m_kwords)

+    {

+    case 3:

+        SIMON_Encrypt<word32, 42>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    case 4:

+        SIMON_Encrypt<word32, 44>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    default:

+        CRYPTOPP_ASSERT(0);;

+    }

+

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef PutBlock<word32, BigEndian, false> OutBlock;

+    OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);

+}

+

+void SIMON64::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const

+{

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef GetBlock<word32, BigEndian, false> InBlock;

+    InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);

+

+    switch (m_kwords)

+    {

+    case 3:

+        SIMON_Decrypt<word32, 42>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    case 4:

+        SIMON_Decrypt<word32, 44>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    default:

+        CRYPTOPP_ASSERT(0);;

+    }

+

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef PutBlock<word32, BigEndian, false> OutBlock;

+    OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);

+}

+#endif

+

+///////////////////////////////////////////////////////////

+

+void SIMON128::Base::UncheckedSetKey(const byte *userKey, unsigned int keyLength, const NameValuePairs &params)

+{

+    CRYPTOPP_ASSERT(keyLength == 16 || keyLength == 24 || keyLength == 32);

+    CRYPTOPP_UNUSED(params);

+

+    // Building the key schedule table requires {2,3,4} words workspace.

+    // Encrypting and decrypting requires 4 words workspace.

+    m_kwords = keyLength/sizeof(word64);

+    m_wspace.New(STDMAX(m_kwords,4U));

+

+    // Avoid GetUserKey. SIMON does unusual things with key string and word ordering

+    // {A,B} -> {B,A}, {A,B,C} -> {C,B,A}, etc.

+    typedef GetBlock<word64, BigEndian, false> InBlock;

+    InBlock iblk(userKey);

+

+    switch (m_kwords)

+    {

+    case 2:

+        m_rkey.New(68);

+        iblk(m_wspace[1])(m_wspace[0]);

+        SIMON128_ExpandKey_68R2K(m_rkey, m_wspace);

+        break;

+    case 3:

+        m_rkey.New(69);

+        iblk(m_wspace[2])(m_wspace[1])(m_wspace[0]);

+        SIMON128_ExpandKey_69R3K(m_rkey, m_wspace);

+        break;

+    case 4:

+        m_rkey.New(72);

+        iblk(m_wspace[3])(m_wspace[2])(m_wspace[1])(m_wspace[0]);

+        SIMON128_ExpandKey_72R4K(m_rkey, m_wspace);

+        break;

+    default:

+        CRYPTOPP_ASSERT(0);;

+    }

+}

+

+void SIMON128::Enc::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const

+{

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef GetBlock<word64, BigEndian, false> InBlock;

+    InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);

+

+    switch (m_kwords)

+    {

+    case 2:

+        SIMON_Encrypt<word64, 68>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    case 3:

+        SIMON_Encrypt<word64, 69>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    case 4:

+        SIMON_Encrypt<word64, 72>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    default:

+        CRYPTOPP_ASSERT(0);;

+    }

+

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef PutBlock<word64, BigEndian, false> OutBlock;

+    OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);

+}

+

+void SIMON128::Dec::ProcessAndXorBlock(const byte *inBlock, const byte *xorBlock, byte *outBlock) const

+{

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef GetBlock<word64, BigEndian, false> InBlock;

+    InBlock iblk(inBlock); iblk(m_wspace[0])(m_wspace[1]);

+

+    switch (m_kwords)

+    {

+    case 2:

+        SIMON_Decrypt<word64, 68>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    case 3:

+        SIMON_Decrypt<word64, 69>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    case 4:

+        SIMON_Decrypt<word64, 72>(m_wspace+2, m_wspace+0, m_rkey);

+        break;

+    default:

+        CRYPTOPP_ASSERT(0);;

+    }

+

+    // Reverse bytes on LittleEndian; align pointer on BigEndian

+    typedef PutBlock<word64, BigEndian, false> OutBlock;

+    OutBlock oblk(xorBlock, outBlock); oblk(m_wspace[2])(m_wspace[3]);

+}

+

+NAMESPACE_END