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authorlloyd <[email protected]>2014-01-10 03:41:59 +0000
committerlloyd <[email protected]>2014-01-10 03:41:59 +0000
commit6894dca64c04936d07048c0e8cbf7e25858548c3 (patch)
tree5d572bfde9fe667dab14e3f04b5285a85d8acd95 /src/lib/stream/salsa20
parent9efa3be92442afb3d0b69890a36c7f122df18eda (diff)
Move lib into src
Diffstat (limited to 'src/lib/stream/salsa20')
-rw-r--r--src/lib/stream/salsa20/info.txt1
-rw-r--r--src/lib/stream/salsa20/salsa20.cpp243
-rw-r--r--src/lib/stream/salsa20/salsa20.h46
3 files changed, 290 insertions, 0 deletions
diff --git a/src/lib/stream/salsa20/info.txt b/src/lib/stream/salsa20/info.txt
new file mode 100644
index 000000000..10f9a8cb2
--- /dev/null
+++ b/src/lib/stream/salsa20/info.txt
@@ -0,0 +1 @@
+define SALSA20 20131128
diff --git a/src/lib/stream/salsa20/salsa20.cpp b/src/lib/stream/salsa20/salsa20.cpp
new file mode 100644
index 000000000..d8db69ae6
--- /dev/null
+++ b/src/lib/stream/salsa20/salsa20.cpp
@@ -0,0 +1,243 @@
+/*
+* Salsa20 / XSalsa20
+* (C) 1999-2010 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/salsa20.h>
+#include <botan/loadstor.h>
+#include <botan/rotate.h>
+#include <botan/internal/xor_buf.h>
+
+namespace Botan {
+
+namespace {
+
+#define SALSA20_QUARTER_ROUND(x1, x2, x3, x4) \
+ do { \
+ x2 ^= rotate_left(x1 + x4, 7); \
+ x3 ^= rotate_left(x2 + x1, 9); \
+ x4 ^= rotate_left(x3 + x2, 13); \
+ x1 ^= rotate_left(x4 + x3, 18); \
+ } while(0)
+
+/*
+* Generate HSalsa20 cipher stream (for XSalsa20 IV setup)
+*/
+void hsalsa20(u32bit output[8], const u32bit input[16])
+ {
+ u32bit x00 = input[ 0], x01 = input[ 1], x02 = input[ 2], x03 = input[ 3],
+ x04 = input[ 4], x05 = input[ 5], x06 = input[ 6], x07 = input[ 7],
+ x08 = input[ 8], x09 = input[ 9], x10 = input[10], x11 = input[11],
+ x12 = input[12], x13 = input[13], x14 = input[14], x15 = input[15];
+
+ for(size_t i = 0; i != 10; ++i)
+ {
+ SALSA20_QUARTER_ROUND(x00, x04, x08, x12);
+ SALSA20_QUARTER_ROUND(x05, x09, x13, x01);
+ SALSA20_QUARTER_ROUND(x10, x14, x02, x06);
+ SALSA20_QUARTER_ROUND(x15, x03, x07, x11);
+
+ SALSA20_QUARTER_ROUND(x00, x01, x02, x03);
+ SALSA20_QUARTER_ROUND(x05, x06, x07, x04);
+ SALSA20_QUARTER_ROUND(x10, x11, x08, x09);
+ SALSA20_QUARTER_ROUND(x15, x12, x13, x14);
+ }
+
+ output[0] = x00;
+ output[1] = x05;
+ output[2] = x10;
+ output[3] = x15;
+ output[4] = x06;
+ output[5] = x07;
+ output[6] = x08;
+ output[7] = x09;
+ }
+
+/*
+* Generate Salsa20 cipher stream
+*/
+void salsa20(byte output[64], const u32bit input[16])
+ {
+ u32bit x00 = input[ 0], x01 = input[ 1], x02 = input[ 2], x03 = input[ 3],
+ x04 = input[ 4], x05 = input[ 5], x06 = input[ 6], x07 = input[ 7],
+ x08 = input[ 8], x09 = input[ 9], x10 = input[10], x11 = input[11],
+ x12 = input[12], x13 = input[13], x14 = input[14], x15 = input[15];
+
+ for(size_t i = 0; i != 10; ++i)
+ {
+ SALSA20_QUARTER_ROUND(x00, x04, x08, x12);
+ SALSA20_QUARTER_ROUND(x05, x09, x13, x01);
+ SALSA20_QUARTER_ROUND(x10, x14, x02, x06);
+ SALSA20_QUARTER_ROUND(x15, x03, x07, x11);
+
+ SALSA20_QUARTER_ROUND(x00, x01, x02, x03);
+ SALSA20_QUARTER_ROUND(x05, x06, x07, x04);
+ SALSA20_QUARTER_ROUND(x10, x11, x08, x09);
+ SALSA20_QUARTER_ROUND(x15, x12, x13, x14);
+ }
+
+ store_le(x00 + input[ 0], output + 4 * 0);
+ store_le(x01 + input[ 1], output + 4 * 1);
+ store_le(x02 + input[ 2], output + 4 * 2);
+ store_le(x03 + input[ 3], output + 4 * 3);
+ store_le(x04 + input[ 4], output + 4 * 4);
+ store_le(x05 + input[ 5], output + 4 * 5);
+ store_le(x06 + input[ 6], output + 4 * 6);
+ store_le(x07 + input[ 7], output + 4 * 7);
+ store_le(x08 + input[ 8], output + 4 * 8);
+ store_le(x09 + input[ 9], output + 4 * 9);
+ store_le(x10 + input[10], output + 4 * 10);
+ store_le(x11 + input[11], output + 4 * 11);
+ store_le(x12 + input[12], output + 4 * 12);
+ store_le(x13 + input[13], output + 4 * 13);
+ store_le(x14 + input[14], output + 4 * 14);
+ store_le(x15 + input[15], output + 4 * 15);
+ }
+
+}
+
+/*
+* Combine cipher stream with message
+*/
+void Salsa20::cipher(const byte in[], byte out[], size_t length)
+ {
+ while(length >= buffer.size() - position)
+ {
+ xor_buf(out, in, &buffer[position], buffer.size() - position);
+ length -= (buffer.size() - position);
+ in += (buffer.size() - position);
+ out += (buffer.size() - position);
+ salsa20(&buffer[0], &state[0]);
+
+ ++state[8];
+ if(!state[8]) // if overflow in state[8]
+ ++state[9]; // carry to state[9]
+
+ position = 0;
+ }
+
+ xor_buf(out, in, &buffer[position], length);
+
+ position += length;
+ }
+
+/*
+* Salsa20 Key Schedule
+*/
+void Salsa20::key_schedule(const byte key[], size_t length)
+ {
+ static const u32bit TAU[] =
+ { 0x61707865, 0x3120646e, 0x79622d36, 0x6b206574 };
+
+ static const u32bit SIGMA[] =
+ { 0x61707865, 0x3320646e, 0x79622d32, 0x6b206574 };
+
+ state.resize(16);
+ buffer.resize(64);
+
+ if(length == 16)
+ {
+ state[0] = TAU[0];
+ state[1] = load_le<u32bit>(key, 0);
+ state[2] = load_le<u32bit>(key, 1);
+ state[3] = load_le<u32bit>(key, 2);
+ state[4] = load_le<u32bit>(key, 3);
+ state[5] = TAU[1];
+ state[10] = TAU[2];
+ state[11] = load_le<u32bit>(key, 0);
+ state[12] = load_le<u32bit>(key, 1);
+ state[13] = load_le<u32bit>(key, 2);
+ state[14] = load_le<u32bit>(key, 3);
+ state[15] = TAU[3];
+ }
+ else if(length == 32)
+ {
+ state[0] = SIGMA[0];
+ state[1] = load_le<u32bit>(key, 0);
+ state[2] = load_le<u32bit>(key, 1);
+ state[3] = load_le<u32bit>(key, 2);
+ state[4] = load_le<u32bit>(key, 3);
+ state[5] = SIGMA[1];
+ state[10] = SIGMA[2];
+ state[11] = load_le<u32bit>(key, 4);
+ state[12] = load_le<u32bit>(key, 5);
+ state[13] = load_le<u32bit>(key, 6);
+ state[14] = load_le<u32bit>(key, 7);
+ state[15] = SIGMA[3];
+ }
+
+ position = 0;
+
+ const byte ZERO[8] = { 0 };
+ set_iv(ZERO, sizeof(ZERO));
+ }
+
+/*
+* Return the name of this type
+*/
+void Salsa20::set_iv(const byte iv[], size_t length)
+ {
+ if(!valid_iv_length(length))
+ throw Invalid_IV_Length(name(), length);
+
+ if(length == 8)
+ {
+ // Salsa20
+ state[6] = load_le<u32bit>(iv, 0);
+ state[7] = load_le<u32bit>(iv, 1);
+ }
+ else
+ {
+ // XSalsa20
+ state[6] = load_le<u32bit>(iv, 0);
+ state[7] = load_le<u32bit>(iv, 1);
+ state[8] = load_le<u32bit>(iv, 2);
+ state[9] = load_le<u32bit>(iv, 3);
+
+ secure_vector<u32bit> hsalsa(8);
+ hsalsa20(&hsalsa[0], &state[0]);
+
+ state[ 1] = hsalsa[0];
+ state[ 2] = hsalsa[1];
+ state[ 3] = hsalsa[2];
+ state[ 4] = hsalsa[3];
+ state[ 6] = load_le<u32bit>(iv, 4);
+ state[ 7] = load_le<u32bit>(iv, 5);
+ state[11] = hsalsa[4];
+ state[12] = hsalsa[5];
+ state[13] = hsalsa[6];
+ state[14] = hsalsa[7];
+ }
+
+ state[8] = 0;
+ state[9] = 0;
+
+ salsa20(&buffer[0], &state[0]);
+ ++state[8];
+ if(!state[8]) // if overflow in state[8]
+ ++state[9]; // carry to state[9]
+
+ position = 0;
+ }
+
+/*
+* Return the name of this type
+*/
+std::string Salsa20::name() const
+ {
+ return "Salsa20";
+ }
+
+/*
+* Clear memory of sensitive data
+*/
+void Salsa20::clear()
+ {
+ zap(state);
+ zap(buffer);
+ position = 0;
+ }
+
+}
diff --git a/src/lib/stream/salsa20/salsa20.h b/src/lib/stream/salsa20/salsa20.h
new file mode 100644
index 000000000..b68bb979e
--- /dev/null
+++ b/src/lib/stream/salsa20/salsa20.h
@@ -0,0 +1,46 @@
+/*
+* Salsa20 / XSalsa20
+* (C) 1999-2010 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#ifndef BOTAN_SALSA20_H__
+#define BOTAN_SALSA20_H__
+
+#include <botan/stream_cipher.h>
+
+namespace Botan {
+
+/**
+* DJB's Salsa20 (and XSalsa20)
+*/
+class BOTAN_DLL Salsa20 : public StreamCipher
+ {
+ public:
+ void cipher(const byte in[], byte out[], size_t length);
+
+ void set_iv(const byte iv[], size_t iv_len);
+
+ bool valid_iv_length(size_t iv_len) const
+ { return (iv_len == 8 || iv_len == 24); }
+
+ Key_Length_Specification key_spec() const
+ {
+ return Key_Length_Specification(16, 32, 16);
+ }
+
+ void clear();
+ std::string name() const;
+ StreamCipher* clone() const { return new Salsa20; }
+ private:
+ void key_schedule(const byte key[], size_t key_len);
+
+ secure_vector<u32bit> state;
+ secure_vector<byte> buffer;
+ size_t position;
+ };
+
+}
+
+#endif