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Diffstat (limited to 'src/modules/common/sapphire.cpp')
| -rw-r--r-- | src/modules/common/sapphire.cpp | 231 |
1 files changed, 0 insertions, 231 deletions
diff --git a/src/modules/common/sapphire.cpp b/src/modules/common/sapphire.cpp deleted file mode 100644 index 1c97934..0000000 --- a/src/modules/common/sapphire.cpp +++ /dev/null @@ -1,231 +0,0 @@ -/* sapphire.cpp -- the Saphire II stream cipher class. - Dedicated to the Public Domain the author and inventor: - (Michael Paul Johnson). This code comes with no warranty. - Use it at your own risk. - Ported from the Pascal implementation of the Sapphire Stream - Cipher 9 December 1994. - Added hash pre- and post-processing 27 December 1994. - Modified initialization to make index variables key dependent, - made the output function more resistant to cryptanalysis, - and renamed to Sapphire II 2 January 1995 -*/ - - -#ifdef WIN32 -#include <memory.h> -#endif - -#ifdef UNIX -#include <memory.h> -#include <unistd.h> -#else -#ifndef _MSC_VER -#include <mem.h> -#endif -#endif - -#ifdef _WIN32_WCE -#include <string.h> -#endif - -#include "sapphire.h" - -SWORD_NAMESPACE_START - -unsigned char sapphire::keyrand(int limit, - unsigned char *user_key, - unsigned char keysize, - unsigned char *rsum, - unsigned *keypos) - { - unsigned u, // Value from 0 to limit to return. - retry_limiter, // No infinite loops allowed. - mask; // Select just enough bits. - - if (!limit) return 0; // Avoid divide by zero error. - retry_limiter = 0; - mask = 1; // Fill mask with enough bits to cover - while (mask < (unsigned)limit) // the desired range. - mask = (mask << 1) + 1; - do - { - *rsum = cards[*rsum] + user_key[(*keypos)++]; - if (*keypos >= keysize) - { - *keypos = 0; // Recycle the user key. - *rsum += keysize; // key "aaaa" != key "aaaaaaaa" - } - u = mask & *rsum; - if (++retry_limiter > 11) - u %= limit; // Prevent very rare long loops. - } - while (u > (unsigned)limit); - return u; - } - -void sapphire::initialize(unsigned char *key, unsigned char keysize) - { - // Key size may be up to 256 bytes. - // Pass phrases may be used directly, with longer length - // compensating for the low entropy expected in such keys. - // Alternatively, shorter keys hashed from a pass phrase or - // generated randomly may be used. For random keys, lengths - // of from 4 to 16 bytes are recommended, depending on how - // secure you want this to be. - - int i; - unsigned char toswap, swaptemp, rsum; - unsigned keypos; - - // If we have been given no key, assume the default hash setup. - - if (keysize < 1) - { - hash_init(); - return; - } - - // Start with cards all in order, one of each. - - for (i=0;i<256;i++) - cards[i] = i; - - // Swap the card at each position with some other card. - - toswap = 0; - keypos = 0; // Start with first byte of user key. - rsum = 0; - for (i=255;i>=0;i--) - { - toswap = keyrand(i, key, keysize, &rsum, &keypos); - swaptemp = cards[i]; - cards[i] = cards[toswap]; - cards[toswap] = swaptemp; - } - - // Initialize the indices and data dependencies. - // Indices are set to different values instead of all 0 - // to reduce what is known about the state of the cards - // when the first byte is emitted. - - rotor = cards[1]; - ratchet = cards[3]; - avalanche = cards[5]; - last_plain = cards[7]; - last_cipher = cards[rsum]; - - toswap = swaptemp = rsum = 0; - keypos = 0; - } - -void sapphire::hash_init(void) - { - // This function is used to initialize non-keyed hash - // computation. - - int i, j; - - // Initialize the indices and data dependencies. - - rotor = 1; - ratchet = 3; - avalanche = 5; - last_plain = 7; - last_cipher = 11; - - // Start with cards all in inverse order. - - for (i=0, j=255;i<256;i++,j--) - cards[i] = (unsigned char) j; - } - -sapphire::sapphire(unsigned char *key, unsigned char keysize) - { - if (key && keysize) - initialize(key, keysize); - } - -void sapphire::burn(void) - { - // Destroy the key and state information in RAM. - memset(cards, 0, 256); - rotor = ratchet = avalanche = last_plain = last_cipher = 0; - } - -sapphire::~sapphire() - { - burn(); - } - -unsigned char sapphire::encrypt(unsigned char b) - { -#ifdef USBINARY - // Picture a single enigma rotor with 256 positions, rewired - // on the fly by card-shuffling. - - // This cipher is a variant of one invented and written - // by Michael Paul Johnson in November, 1993. - - unsigned char swaptemp; - - // Shuffle the deck a little more. - - ratchet += cards[rotor++]; - swaptemp = cards[last_cipher]; - cards[last_cipher] = cards[ratchet]; - cards[ratchet] = cards[last_plain]; - cards[last_plain] = cards[rotor]; - cards[rotor] = swaptemp; - avalanche += cards[swaptemp]; - - // Output one byte from the state in such a way as to make it - // very hard to figure out which one you are looking at. - - last_cipher = b^cards[(cards[ratchet] + cards[rotor]) & 0xFF] ^ - cards[cards[(cards[last_plain] + - cards[last_cipher] + - cards[avalanche])&0xFF]]; - last_plain = b; - return last_cipher; -#else - return b; -#endif - } - -unsigned char sapphire::decrypt(unsigned char b) - { - unsigned char swaptemp; - - // Shuffle the deck a little more. - - ratchet += cards[rotor++]; - swaptemp = cards[last_cipher]; - cards[last_cipher] = cards[ratchet]; - cards[ratchet] = cards[last_plain]; - cards[last_plain] = cards[rotor]; - cards[rotor] = swaptemp; - avalanche += cards[swaptemp]; - - // Output one byte from the state in such a way as to make it - // very hard to figure out which one you are looking at. - - last_plain = b^cards[(cards[ratchet] + cards[rotor]) & 0xFF] ^ - cards[cards[(cards[last_plain] + - cards[last_cipher] + - cards[avalanche])&0xFF]]; - last_cipher = b; - return last_plain; - } - -void sapphire::hash_final(unsigned char *hash, // Destination - unsigned char hashlength) // Size of hash. - { - int i; - - for (i=255;i>=0;i--) - encrypt((unsigned char) i); - for (i=0;i<hashlength;i++) - hash[i] = encrypt(0); - } - -SWORD_NAMESPACE_END |