diff options
Diffstat (limited to 'include/crypto/gf128mul.h')
| -rw-r--r-- | include/crypto/gf128mul.h | 47 |
1 files changed, 25 insertions, 22 deletions
diff --git a/include/crypto/gf128mul.h b/include/crypto/gf128mul.h index da2530e34b26..230760aef93b 100644 --- a/include/crypto/gf128mul.h +++ b/include/crypto/gf128mul.h @@ -43,7 +43,7 @@ --------------------------------------------------------------------------- Issue Date: 31/01/2006 - An implementation of field multiplication in Galois Field GF(128) + An implementation of field multiplication in Galois Field GF(2^128) */ #ifndef _CRYPTO_GF128MUL_H @@ -65,7 +65,7 @@ * are left and the lsb's are right. char b[16] is an array and b[0] is * the first octet. * - * 80000000 00000000 00000000 00000000 .... 00000000 00000000 00000000 + * 10000000 00000000 00000000 00000000 .... 00000000 00000000 00000000 * b[0] b[1] b[2] b[3] b[13] b[14] b[15] * * Every bit is a coefficient of some power of X. We can store the bits @@ -99,21 +99,21 @@ * * bbe on a little endian machine u32 x[4]: * - * MS x[0] LS MS x[1] LS + * MS x[0] LS MS x[1] LS * ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls * 103..96 111.104 119.112 127.120 71...64 79...72 87...80 95...88 * - * MS x[2] LS MS x[3] LS + * MS x[2] LS MS x[3] LS * ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls * 39...32 47...40 55...48 63...56 07...00 15...08 23...16 31...24 * * ble on a little endian machine * - * MS x[0] LS MS x[1] LS + * MS x[0] LS MS x[1] LS * ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls * 31...24 23...16 15...08 07...00 63...56 55...48 47...40 39...32 * - * MS x[2] LS MS x[3] LS + * MS x[2] LS MS x[3] LS * ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls * 95...88 87...80 79...72 71...64 127.120 199.112 111.104 103..96 * @@ -127,7 +127,7 @@ * machines this will automatically aligned to wordsize and on a 64-bit * machine also. */ -/* Multiply a GF128 field element by x. Field elements are held in arrays +/* Multiply a GF128 field element by x. Field elements are held in arrays of bytes in which field bits 8n..8n + 7 are held in byte[n], with lower indexed bits placed in the more numerically significant bit positions within bytes. @@ -135,62 +135,65 @@ On little endian machines the bit indexes translate into the bit positions within four 32-bit words in the following way - MS x[0] LS MS x[1] LS + MS x[0] LS MS x[1] LS ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls 24...31 16...23 08...15 00...07 56...63 48...55 40...47 32...39 - MS x[2] LS MS x[3] LS + MS x[2] LS MS x[3] LS ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls 88...95 80...87 72...79 64...71 120.127 112.119 104.111 96..103 On big endian machines the bit indexes translate into the bit positions within four 32-bit words in the following way - MS x[0] LS MS x[1] LS + MS x[0] LS MS x[1] LS ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls 00...07 08...15 16...23 24...31 32...39 40...47 48...55 56...63 - MS x[2] LS MS x[3] LS + MS x[2] LS MS x[3] LS ms ls ms ls ms ls ms ls ms ls ms ls ms ls ms ls 64...71 72...79 80...87 88...95 96..103 104.111 112.119 120.127 */ -/* A slow generic version of gf_mul, implemented for lle and bbe - * It multiplies a and b and puts the result in a */ +/* A slow generic version of gf_mul, implemented for lle, bbe, and ble. + * It multiplies a and b and puts the result in a + */ void gf128mul_lle(be128 *a, const be128 *b); - void gf128mul_bbe(be128 *a, const be128 *b); +void gf128mul_ble(be128 *a, const be128 *b); -/* multiply by x in ble format, needed by XTS */ +/* multiply by x in ble format, needed by XTS and HEH */ void gf128mul_x_ble(be128 *a, const be128 *b); /* 4k table optimization */ - struct gf128mul_4k { be128 t[256]; }; struct gf128mul_4k *gf128mul_init_4k_lle(const be128 *g); struct gf128mul_4k *gf128mul_init_4k_bbe(const be128 *g); +struct gf128mul_4k *gf128mul_init_4k_ble(const be128 *g); void gf128mul_4k_lle(be128 *a, struct gf128mul_4k *t); void gf128mul_4k_bbe(be128 *a, struct gf128mul_4k *t); +void gf128mul_4k_ble(be128 *a, struct gf128mul_4k *t); static inline void gf128mul_free_4k(struct gf128mul_4k *t) { - kfree(t); + kzfree(t); } -/* 64k table optimization, implemented for lle and bbe */ +/* 64k table optimization, implemented for lle, ble, and bbe */ struct gf128mul_64k { struct gf128mul_4k *t[16]; }; -/* first initialize with the constant factor with which you - * want to multiply and then call gf128_64k_lle with the other - * factor in the first argument, the table in the second and a - * scratch register in the third. Afterwards *a = *r. */ +/* First initialize with the constant factor with which you + * want to multiply and then call gf128mul_64k_bbe with the other + * factor in the first argument, and the table in the second. + * Afterwards, the result is stored in *a. + */ struct gf128mul_64k *gf128mul_init_64k_lle(const be128 *g); struct gf128mul_64k *gf128mul_init_64k_bbe(const be128 *g); void gf128mul_free_64k(struct gf128mul_64k *t); |