^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 1) // SPDX-License-Identifier: GPL-2.0-or-later
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 2) /*
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 3) * Twofish for CryptoAPI
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 4) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 5) * Originally Twofish for GPG
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 6) * By Matthew Skala <mskala@ansuz.sooke.bc.ca>, July 26, 1998
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 7) * 256-bit key length added March 20, 1999
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 8) * Some modifications to reduce the text size by Werner Koch, April, 1998
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 9) * Ported to the kerneli patch by Marc Mutz <Marc@Mutz.com>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 10) * Ported to CryptoAPI by Colin Slater <hoho@tacomeat.net>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 11) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 12) * The original author has disclaimed all copyright interest in this
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 13) * code and thus put it in the public domain. The subsequent authors
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 14) * have put this under the GNU General Public License.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 15) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 16) * This code is a "clean room" implementation, written from the paper
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 17) * _Twofish: A 128-Bit Block Cipher_ by Bruce Schneier, John Kelsey,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 18) * Doug Whiting, David Wagner, Chris Hall, and Niels Ferguson, available
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 19) * through http://www.counterpane.com/twofish.html
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 20) *
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 21) * For background information on multiplication in finite fields, used for
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 22) * the matrix operations in the key schedule, see the book _Contemporary
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 23) * Abstract Algebra_ by Joseph A. Gallian, especially chapter 22 in the
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 24) * Third Edition.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 25) */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 26)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 27) #include <asm/byteorder.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 28) #include <crypto/twofish.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 29) #include <linux/module.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 30) #include <linux/init.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 31) #include <linux/types.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 32) #include <linux/errno.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 33) #include <linux/crypto.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 34) #include <linux/bitops.h>
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 35)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 36) /* Macros to compute the g() function in the encryption and decryption
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 37) * rounds. G1 is the straight g() function; G2 includes the 8-bit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 38) * rotation for the high 32-bit word. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 39)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 40) #define G1(a) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 41) (ctx->s[0][(a) & 0xFF]) ^ (ctx->s[1][((a) >> 8) & 0xFF]) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 42) ^ (ctx->s[2][((a) >> 16) & 0xFF]) ^ (ctx->s[3][(a) >> 24])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 43)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 44) #define G2(b) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 45) (ctx->s[1][(b) & 0xFF]) ^ (ctx->s[2][((b) >> 8) & 0xFF]) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 46) ^ (ctx->s[3][((b) >> 16) & 0xFF]) ^ (ctx->s[0][(b) >> 24])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 47)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 48) /* Encryption and decryption Feistel rounds. Each one calls the two g()
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 49) * macros, does the PHT, and performs the XOR and the appropriate bit
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 50) * rotations. The parameters are the round number (used to select subkeys),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 51) * and the four 32-bit chunks of the text. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 52)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 53) #define ENCROUND(n, a, b, c, d) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 54) x = G1 (a); y = G2 (b); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 55) x += y; y += x + ctx->k[2 * (n) + 1]; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 56) (c) ^= x + ctx->k[2 * (n)]; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 57) (c) = ror32((c), 1); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 58) (d) = rol32((d), 1) ^ y
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 59)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 60) #define DECROUND(n, a, b, c, d) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 61) x = G1 (a); y = G2 (b); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 62) x += y; y += x; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 63) (d) ^= y + ctx->k[2 * (n) + 1]; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 64) (d) = ror32((d), 1); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 65) (c) = rol32((c), 1); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 66) (c) ^= (x + ctx->k[2 * (n)])
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 67)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 68) /* Encryption and decryption cycles; each one is simply two Feistel rounds
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 69) * with the 32-bit chunks re-ordered to simulate the "swap" */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 70)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 71) #define ENCCYCLE(n) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 72) ENCROUND (2 * (n), a, b, c, d); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 73) ENCROUND (2 * (n) + 1, c, d, a, b)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 74)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 75) #define DECCYCLE(n) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 76) DECROUND (2 * (n) + 1, c, d, a, b); \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 77) DECROUND (2 * (n), a, b, c, d)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 78)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 79) /* Macros to convert the input and output bytes into 32-bit words,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 80) * and simultaneously perform the whitening step. INPACK packs word
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 81) * number n into the variable named by x, using whitening subkey number m.
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 82) * OUTUNPACK unpacks word number n from the variable named by x, using
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 83) * whitening subkey number m. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 84)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 85) #define INPACK(n, x, m) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 86) x = le32_to_cpu(src[n]) ^ ctx->w[m]
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 87)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 88) #define OUTUNPACK(n, x, m) \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 89) x ^= ctx->w[m]; \
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 90) dst[n] = cpu_to_le32(x)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 91)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 92)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 93)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 94) /* Encrypt one block. in and out may be the same. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 95) static void twofish_encrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 96) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 97) struct twofish_ctx *ctx = crypto_tfm_ctx(tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 98) const __le32 *src = (const __le32 *)in;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 99) __le32 *dst = (__le32 *)out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 100)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 101) /* The four 32-bit chunks of the text. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 102) u32 a, b, c, d;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 103)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 104) /* Temporaries used by the round function. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 105) u32 x, y;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 106)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 107) /* Input whitening and packing. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 108) INPACK (0, a, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 109) INPACK (1, b, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 110) INPACK (2, c, 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 111) INPACK (3, d, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 112)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 113) /* Encryption Feistel cycles. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 114) ENCCYCLE (0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 115) ENCCYCLE (1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 116) ENCCYCLE (2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 117) ENCCYCLE (3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 118) ENCCYCLE (4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 119) ENCCYCLE (5);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 120) ENCCYCLE (6);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 121) ENCCYCLE (7);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 122)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 123) /* Output whitening and unpacking. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 124) OUTUNPACK (0, c, 4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 125) OUTUNPACK (1, d, 5);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 126) OUTUNPACK (2, a, 6);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 127) OUTUNPACK (3, b, 7);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 128)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 129) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 130)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 131) /* Decrypt one block. in and out may be the same. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 132) static void twofish_decrypt(struct crypto_tfm *tfm, u8 *out, const u8 *in)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 133) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 134) struct twofish_ctx *ctx = crypto_tfm_ctx(tfm);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 135) const __le32 *src = (const __le32 *)in;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 136) __le32 *dst = (__le32 *)out;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 137)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 138) /* The four 32-bit chunks of the text. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 139) u32 a, b, c, d;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 140)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 141) /* Temporaries used by the round function. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 142) u32 x, y;
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 143)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 144) /* Input whitening and packing. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 145) INPACK (0, c, 4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 146) INPACK (1, d, 5);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 147) INPACK (2, a, 6);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 148) INPACK (3, b, 7);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 149)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 150) /* Encryption Feistel cycles. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 151) DECCYCLE (7);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 152) DECCYCLE (6);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 153) DECCYCLE (5);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 154) DECCYCLE (4);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 155) DECCYCLE (3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 156) DECCYCLE (2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 157) DECCYCLE (1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 158) DECCYCLE (0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 159)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 160) /* Output whitening and unpacking. */
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 161) OUTUNPACK (0, a, 0);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 162) OUTUNPACK (1, b, 1);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 163) OUTUNPACK (2, c, 2);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 164) OUTUNPACK (3, d, 3);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 165)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 166) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 167)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 168) static struct crypto_alg alg = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 169) .cra_name = "twofish",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 170) .cra_driver_name = "twofish-generic",
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 171) .cra_priority = 100,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 172) .cra_flags = CRYPTO_ALG_TYPE_CIPHER,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 173) .cra_blocksize = TF_BLOCK_SIZE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 174) .cra_ctxsize = sizeof(struct twofish_ctx),
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 175) .cra_alignmask = 3,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 176) .cra_module = THIS_MODULE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 177) .cra_u = { .cipher = {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 178) .cia_min_keysize = TF_MIN_KEY_SIZE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 179) .cia_max_keysize = TF_MAX_KEY_SIZE,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 180) .cia_setkey = twofish_setkey,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 181) .cia_encrypt = twofish_encrypt,
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 182) .cia_decrypt = twofish_decrypt } }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 183) };
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 184)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 185) static int __init twofish_mod_init(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 186) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 187) return crypto_register_alg(&alg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 188) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 189)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 190) static void __exit twofish_mod_fini(void)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 191) {
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 192) crypto_unregister_alg(&alg);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 193) }
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 194)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 195) subsys_initcall(twofish_mod_init);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 196) module_exit(twofish_mod_fini);
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 197)
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 198) MODULE_LICENSE("GPL");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 199) MODULE_DESCRIPTION ("Twofish Cipher Algorithm");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 200) MODULE_ALIAS_CRYPTO("twofish");
^8f3ce5b39 (kx 2023-10-28 12:00:06 +0300 201) MODULE_ALIAS_CRYPTO("twofish-generic");
Orange Pi5 kernel
Deprecated Linux kernel 5.10.110 for OrangePi 5/5B/5+ boards
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