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sjaeckelsjaeckel
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add TEA
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6 files changed

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‎src/ciphers/tea.c‎

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/* LibTomCrypt, modular cryptographic library -- Tom St Denis
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*
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* LibTomCrypt is a library that provides various cryptographic
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* algorithms in a highly modular and flexible manner.
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*
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* The library is free for all purposes without any express
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* guarantee it works.
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*/
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/**
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@file tea.c
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Implementation of TEA, Steffen Jaeckel
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*/
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#include "tomcrypt_private.h"
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#ifdef LTC_TEA
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const struct ltc_cipher_descriptor tea_desc =
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{
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"tea",
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26,
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16, 16, 8, 32,
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&tea_setup,
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&tea_ecb_encrypt,
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&tea_ecb_decrypt,
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&tea_test,
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&tea_done,
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&tea_keysize,
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NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL, NULL
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};
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#define DELTA 0x9E3779B9uL
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#define SUM 0xC6EF3720uL
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int tea_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey)
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{
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LTC_ARGCHK(key != NULL);
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LTC_ARGCHK(skey != NULL);
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/* check arguments */
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if (keylen != 16) {
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return CRYPT_INVALID_KEYSIZE;
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}
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if (num_rounds != 0 && num_rounds != 32) {
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return CRYPT_INVALID_ROUNDS;
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}
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/* load key */
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LOAD32H(skey->tea.k[0], key+0);
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LOAD32H(skey->tea.k[1], key+4);
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LOAD32H(skey->tea.k[2], key+8);
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LOAD32H(skey->tea.k[3], key+12);
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return CRYPT_OK;
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}
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/**
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Encrypts a block of text with TEA
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@param pt The input plaintext (8 bytes)
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@param ct The output ciphertext (8 bytes)
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@param skey The key as scheduled
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@return CRYPT_OK if successful
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*/
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int tea_ecb_encrypt(const unsigned char *pt, unsigned char *ct, const symmetric_key *skey)
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{
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ulong32 y, z, sum = 0;
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const ulong32 delta = DELTA;
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int r;
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LTC_ARGCHK(pt != NULL);
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LTC_ARGCHK(ct != NULL);
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LTC_ARGCHK(skey != NULL);
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LOAD32H(y, &pt[0]);
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LOAD32H(z, &pt[4]);
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for (r = 0; r < 32; r += 4) {
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sum += delta;
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y += ((z<<4) + skey->tea.k[0]) ^ (z + sum) ^ ((z>>5) + skey->tea.k[1]);
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z += ((y<<4) + skey->tea.k[2]) ^ (y + sum) ^ ((y>>5) + skey->tea.k[3]);
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}
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STORE32H(y, &ct[0]);
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STORE32H(z, &ct[4]);
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return CRYPT_OK;
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}
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/**
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Decrypts a block of text with TEA
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@param ct The input ciphertext (8 bytes)
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@param pt The output plaintext (8 bytes)
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@param skey The key as scheduled
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@return CRYPT_OK if successful
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*/
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int tea_ecb_decrypt(const unsigned char *ct, unsigned char *pt, const symmetric_key *skey)
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{
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ulong32 v0, v1, sum = SUM;
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const ulong32 delta = DELTA;
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int r;
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LTC_ARGCHK(pt != NULL);
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LTC_ARGCHK(ct != NULL);
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LTC_ARGCHK(skey != NULL);
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LOAD32H(v0, &ct[0]);
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LOAD32H(v1, &ct[4]);
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for (r = 0; r < 32; r++) {
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v1 -= ((v0 << 4) + skey->tea.k[2]) ^ (v0 + sum) ^ ((v0 >> 5) + skey->tea.k[3]);
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v0 -= ((v1 << 4) + skey->tea.k[0]) ^ (v1 + sum) ^ ((v1 >> 5) + skey->tea.k[1]);
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sum -= delta;
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}
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STORE32H(v0, &pt[0]);
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STORE32H(v1, &pt[4]);
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return CRYPT_OK;
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}
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/**
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Performs a self-test of the TEA block cipher
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@return CRYPT_OK if functional, CRYPT_NOP if self-test has been disabled
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*/
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int tea_test(void)
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{
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#ifndef LTC_TEST
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return CRYPT_NOP;
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#else
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static const struct {
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const char *key, *pt, *ct;
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} tests[] = {
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{
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"00000000000000000000000000000000",
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"0000000000000000",
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"41ea3a0a94baa940"
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}, {
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"32a1e65408b63bb9214105744ec5d2e2",
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"5ada1d89a9c3801a",
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"dd46249e28aa0b4b"
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}, {
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"60388adadf70a1f5d9cb4e097d2c6c57",
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"7a6adb4d69c53e0f",
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"44b71215cf25368a"
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}, {
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"4368d2249bd0321eb7c56d5b63a1bfac",
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"5a5d7ca2e186c41a",
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"91f56dff7281794f"
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}, {
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"5c60bff27072d01c4513c5eb8f3a38ab",
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"80d9c4adcf899635",
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"2bb0f1b3c023ed11"
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}
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};
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unsigned char ptct[2][8];
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unsigned char tmp[2][8];
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unsigned char key[16];
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unsigned long l;
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symmetric_key skey;
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size_t i;
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int err, y;
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for (i = 0; i < sizeof(tests)/sizeof(tests[0]); i++) {
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zeromem(&skey, sizeof(skey));
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l = sizeof(key);
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if ((err = base16_decode(tests[i].key, strlen(tests[i].key), key, &l)) != CRYPT) return err;
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l = sizeof(ptct[0]);
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if ((err = base16_decode(tests[i].pt, strlen(tests[i].pt), ptct[0], &l)) != CRYPT) return err;
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l = sizeof(ptct[1]);
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if ((err = base16_decode(tests[i].ct, strlen(tests[i].ct), ptct[1], &l)) != CRYPT) return err;
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if ((err = tea_setup(key, 16, 0, &skey)) != CRYPT_OK) {
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return err;
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}
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tea_ecb_encrypt(ptct[0], tmp[0], &skey);
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tea_ecb_decrypt(tmp[0], tmp[1], &skey);
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if (compare_testvector(tmp[0], 8, ptct[0], 8, "TEA Encrypt", i) != 0 ||
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compare_testvector(tmp[1], 8, ptct[1], 8, "TEA Decrypt", i) != 0) {
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return CRYPT_FAIL_TESTVECTOR;
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}
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/* now see if we can encrypt all zero bytes 1000 times, decrypt and come back where we started */
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for (y = 0; y < 8; y++) tmp[0][y] = 0;
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for (y = 0; y < 1000; y++) tea_ecb_encrypt(tmp[0], tmp[0], &skey);
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for (y = 0; y < 1000; y++) tea_ecb_decrypt(tmp[0], tmp[0], &skey);
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for (y = 0; y < 8; y++) if (tmp[0][y] != 0) return CRYPT_FAIL_TESTVECTOR;
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} /* for */
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return CRYPT_OK;
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#endif
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}
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/** Terminate the context
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@param skey The scheduled key
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*/
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void tea_done(symmetric_key *skey)
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{
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LTC_UNUSED_PARAM(skey);
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}
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/**
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Gets suitable key size
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@param keysize [in/out] The length of the recommended key (in bytes). This function will store the suitable size back in this variable.
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@return CRYPT_OK if the input key size is acceptable.
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*/
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int tea_keysize(int *keysize)
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{
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LTC_ARGCHK(keysize != NULL);
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if (*keysize < 16) {
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return CRYPT_INVALID_KEYSIZE;
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}
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*keysize = 16;
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return CRYPT_OK;
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}
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#endif
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/* ref: $Format:%D$ */
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/* git commit: $Format:%H$ */
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/* commit time: $Format:%ai$ */

‎src/ciphers/xtea.c‎

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@@ -9,7 +9,7 @@
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/**
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@file xtea.c
12-
Implementation of LTC_XTEA, Tom St Denis
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Implementation of eXtended TEA, Tom St Denis
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*/
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#include "tomcrypt_private.h"
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‎src/headers/tomcrypt_cipher.h‎

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@@ -171,6 +171,12 @@ struct serpent_key {
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};
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#endif
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#ifdef LTC_TEA
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struct tea_key {
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ulong32 k[4];
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};
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#endif
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typedef union Symmetric_key {
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#ifdef LTC_DES
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struct des_key des;
@@ -235,6 +241,9 @@ typedef union Symmetric_key {
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#endif
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#ifdef LTC_SERPENT
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struct serpent_key serpent;
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#endif
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#ifdef LTC_TEA
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struct tea_key tea;
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#endif
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void *data;
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} symmetric_key;
@@ -859,6 +868,16 @@ int serpent_keysize(int *keysize);
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extern const struct ltc_cipher_descriptor serpent_desc;
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#endif
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#ifdef LTC_TEA
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int tea_setup(const unsigned char *key, int keylen, int num_rounds, symmetric_key *skey);
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int tea_ecb_encrypt(const unsigned char *pt, unsigned char *ct, const symmetric_key *skey);
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int tea_ecb_decrypt(const unsigned char *ct, unsigned char *pt, const symmetric_key *skey);
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int tea_test(void);
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void tea_done(symmetric_key *skey);
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int tea_keysize(int *keysize);
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extern const struct ltc_cipher_descriptor tea_desc;
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#endif
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#ifdef LTC_ECB_MODE
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int ecb_start(int cipher, const unsigned char *key,
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int keylen, int num_rounds, symmetric_ECB *ecb);

‎src/headers/tomcrypt_custom.h‎

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#define LTC_CAMELLIA
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#define LTC_IDEA
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#define LTC_SERPENT
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#define LTC_TEA
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/* stream ciphers */
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#define LTC_CHACHA

‎src/misc/crypt/crypt.c‎

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@@ -127,6 +127,9 @@ const char *crypt_build_settings =
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#endif
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#if defined(LTC_SERPENT)
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" Serpent\n"
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#endif
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#if defined(LTC_TEA)
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" TEA\n"
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#endif
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"Stream ciphers built-in:\n"
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#if defined(LTC_CHACHA)

‎src/misc/crypt/crypt_register_all_ciphers.c‎

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@@ -97,6 +97,9 @@ int register_all_ciphers(void)
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#endif
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#ifdef LTC_SERPENT
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REGISTER_CIPHER(&serpent_desc);
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#endif
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#ifdef LTC_TEA
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REGISTER_CIPHER(&tea_desc);
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#endif
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return CRYPT_OK;
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}

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