crypto/aegis128-neon-inner.c

   1 // SPDX-License-Identifier: GPL-2.0-or-later
   2 /*
   3  * Copyright (C) 2019 Linaro, Ltd. <ard.biesheuvel@linaro.org>
   4  */
   5
   6 #ifdef CONFIG_ARM64
   7 #include <asm/neon-intrinsics.h>
   8
   9 #define AES_ROUND       "aese %0.16b, %1.16b \n\t aesmc %0.16b, %0.16b"
  10 #else
  11 #include <arm_neon.h>
  12
  13 #define AES_ROUND       "aese.8 %q0, %q1 \n\t aesmc.8 %q0, %q0"
  14 #endif
  15
  16 #define AEGIS_BLOCK_SIZE        16
  17
  18 #include <stddef.h>
  19 #include "aegis-neon.h"
  20
  21 extern int aegis128_have_aes_insn;
  22
  23 void *memcpy(void *dest, const void *src, size_t n);
  24
  25 struct aegis128_state {
  26         uint8x16_t v[5];
  27 };
  28
  29 extern const uint8_t crypto_aes_sbox[];
  30
  31 static struct aegis128_state aegis128_load_state_neon(const void *state)
  32 {
  33         return (struct aegis128_state){ {
  34                 vld1q_u8(state),
  35                 vld1q_u8(state + 16),
  36                 vld1q_u8(state + 32),
  37                 vld1q_u8(state + 48),
  38                 vld1q_u8(state + 64)
  39         } };
  40 }
  41
  42 static void aegis128_save_state_neon(struct aegis128_state st, void *state)
  43 {
  44         vst1q_u8(state, st.v[0]);
  45         vst1q_u8(state + 16, st.v[1]);
  46         vst1q_u8(state + 32, st.v[2]);
  47         vst1q_u8(state + 48, st.v[3]);
  48         vst1q_u8(state + 64, st.v[4]);
  49 }
  50
  51 static inline __attribute__((always_inline))
  52 uint8x16_t aegis_aes_round(uint8x16_t w)
  53 {
  54         uint8x16_t z = {};
  55
  56 #ifdef CONFIG_ARM64
  57         if (!__builtin_expect(aegis128_have_aes_insn, 1)) {
  58                 static const uint8_t shift_rows[] = {
  59                         0x0, 0x5, 0xa, 0xf, 0x4, 0x9, 0xe, 0x3,
  60                         0x8, 0xd, 0x2, 0x7, 0xc, 0x1, 0x6, 0xb,
  61                 };
  62                 static const uint8_t ror32by8[] = {
  63                         0x1, 0x2, 0x3, 0x0, 0x5, 0x6, 0x7, 0x4,
  64                         0x9, 0xa, 0xb, 0x8, 0xd, 0xe, 0xf, 0xc,
  65                 };
  66                 uint8x16_t v;
  67
  68                 // shift rows
  69                 w = vqtbl1q_u8(w, vld1q_u8(shift_rows));
  70
  71                 // sub bytes
  72 #ifndef CONFIG_CC_IS_GCC
  73                 v = vqtbl4q_u8(vld1q_u8_x4(crypto_aes_sbox), w);
  74                 v = vqtbx4q_u8(v, vld1q_u8_x4(crypto_aes_sbox + 0x40), w - 0x40);
  75                 v = vqtbx4q_u8(v, vld1q_u8_x4(crypto_aes_sbox + 0x80), w - 0x80);
  76                 v = vqtbx4q_u8(v, vld1q_u8_x4(crypto_aes_sbox + 0xc0), w - 0xc0);
  77 #else
  78                 asm("tbl %0.16b, {v16.16b-v19.16b}, %1.16b" : "=w"(v) : "w"(w));
  79                 w -= 0x40;
  80                 asm("tbx %0.16b, {v20.16b-v23.16b}, %1.16b" : "+w"(v) : "w"(w));
  81                 w -= 0x40;
  82                 asm("tbx %0.16b, {v24.16b-v27.16b}, %1.16b" : "+w"(v) : "w"(w));
  83                 w -= 0x40;
  84                 asm("tbx %0.16b, {v28.16b-v31.16b}, %1.16b" : "+w"(v) : "w"(w));
  85 #endif
  86
  87                 // mix columns
  88                 w = (v << 1) ^ (uint8x16_t)(((int8x16_t)v >> 7) & 0x1b);
  89                 w ^= (uint8x16_t)vrev32q_u16((uint16x8_t)v);
  90                 w ^= vqtbl1q_u8(v ^ w, vld1q_u8(ror32by8));
  91
  92                 return w;
  93         }
  94 #endif
  95
  96         /*
  97          * We use inline asm here instead of the vaeseq_u8/vaesmcq_u8 intrinsics
  98          * to force the compiler to issue the aese/aesmc instructions in pairs.
  99          * This is much faster on many cores, where the instruction pair can
 100          * execute in a single cycle.
 101          */
 102         asm(AES_ROUND : "+w"(w) : "w"(z));
 103         return w;
 104 }
 105
 106 static inline __attribute__((always_inline))
 107 struct aegis128_state aegis128_update_neon(struct aegis128_state st,
 108                                            uint8x16_t m)
 109 {
 110         m       ^= aegis_aes_round(st.v[4]);
 111         st.v[4] ^= aegis_aes_round(st.v[3]);
 112         st.v[3] ^= aegis_aes_round(st.v[2]);
 113         st.v[2] ^= aegis_aes_round(st.v[1]);
 114         st.v[1] ^= aegis_aes_round(st.v[0]);
 115         st.v[0] ^= m;
 116
 117         return st;
 118 }
 119
 120 static inline __attribute__((always_inline))
 121 void preload_sbox(void)
 122 {
 123         if (!IS_ENABLED(CONFIG_ARM64) ||
 124             !IS_ENABLED(CONFIG_CC_IS_GCC) ||
 125             __builtin_expect(aegis128_have_aes_insn, 1))
 126                 return;
 127
 128         asm("ld1        {v16.16b-v19.16b}, [%0], #64    \n\t"
 129             "ld1        {v20.16b-v23.16b}, [%0], #64    \n\t"
 130             "ld1        {v24.16b-v27.16b}, [%0], #64    \n\t"
 131             "ld1        {v28.16b-v31.16b}, [%0]         \n\t"
 132             :: "r"(crypto_aes_sbox));
 133 }
 134
 135 void crypto_aegis128_init_neon(void *state, const void *key, const void *iv)
 136 {
 137         static const uint8_t const0[] = {
 138                 0x00, 0x01, 0x01, 0x02, 0x03, 0x05, 0x08, 0x0d,
 139                 0x15, 0x22, 0x37, 0x59, 0x90, 0xe9, 0x79, 0x62,
 140         };
 141         static const uint8_t const1[] = {
 142                 0xdb, 0x3d, 0x18, 0x55, 0x6d, 0xc2, 0x2f, 0xf1,
 143                 0x20, 0x11, 0x31, 0x42, 0x73, 0xb5, 0x28, 0xdd,
 144         };
 145         uint8x16_t k = vld1q_u8(key);
 146         uint8x16_t kiv = k ^ vld1q_u8(iv);
 147         struct aegis128_state st = {{
 148                 kiv,
 149                 vld1q_u8(const1),
 150                 vld1q_u8(const0),
 151                 k ^ vld1q_u8(const0),
 152                 k ^ vld1q_u8(const1),
 153         }};
 154         int i;
 155
 156         preload_sbox();
 157
 158         for (i = 0; i < 5; i++) {
 159                 st = aegis128_update_neon(st, k);
 160                 st = aegis128_update_neon(st, kiv);
 161         }
 162         aegis128_save_state_neon(st, state);
 163 }
 164
 165 void crypto_aegis128_update_neon(void *state, const void *msg)
 166 {
 167         struct aegis128_state st = aegis128_load_state_neon(state);
 168
 169         preload_sbox();
 170
 171         st = aegis128_update_neon(st, vld1q_u8(msg));
 172
 173         aegis128_save_state_neon(st, state);
 174 }
 175
 176 #ifdef CONFIG_ARM
 177 /*
 178  * AArch32 does not provide these intrinsics natively because it does not
 179  * implement the underlying instructions. AArch32 only provides 64-bit
 180  * wide vtbl.8/vtbx.8 instruction, so use those instead.
 181  */
 182 static uint8x16_t vqtbl1q_u8(uint8x16_t a, uint8x16_t b)
 183 {
 184         union {
 185                 uint8x16_t      val;
 186                 uint8x8x2_t     pair;
 187         } __a = { a };
 188
 189         return vcombine_u8(vtbl2_u8(__a.pair, vget_low_u8(b)),
 190                            vtbl2_u8(__a.pair, vget_high_u8(b)));
 191 }
 192
 193 static uint8x16_t vqtbx1q_u8(uint8x16_t v, uint8x16_t a, uint8x16_t b)
 194 {
 195         union {
 196                 uint8x16_t      val;
 197                 uint8x8x2_t     pair;
 198         } __a = { a };
 199
 200         return vcombine_u8(vtbx2_u8(vget_low_u8(v), __a.pair, vget_low_u8(b)),
 201                            vtbx2_u8(vget_high_u8(v), __a.pair, vget_high_u8(b)));
 202 }
 203
 204 static int8_t vminvq_s8(int8x16_t v)
 205 {
 206         int8x8_t s = vpmin_s8(vget_low_s8(v), vget_high_s8(v));
 207
 208         s = vpmin_s8(s, s);
 209         s = vpmin_s8(s, s);
 210         s = vpmin_s8(s, s);
 211
 212         return vget_lane_s8(s, 0);
 213 }
 214 #endif
 215
 216 static const uint8_t permute[] __aligned(64) = {
 217         -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 218          0,  1,  2,  3,  4,  5,  6,  7,  8,  9, 10, 11, 12, 13, 14, 15,
 219         -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1, -1,
 220 };
 221
 222 void crypto_aegis128_encrypt_chunk_neon(void *state, void *dst, const void *src,
 223                                         unsigned int size)
 224 {
 225         struct aegis128_state st = aegis128_load_state_neon(state);
 226         const int short_input = size < AEGIS_BLOCK_SIZE;
 227         uint8x16_t msg;
 228
 229         preload_sbox();
 230
 231         while (size >= AEGIS_BLOCK_SIZE) {
 232                 uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
 233
 234                 msg = vld1q_u8(src);
 235                 st = aegis128_update_neon(st, msg);
 236                 msg ^= s;
 237                 vst1q_u8(dst, msg);
 238
 239                 size -= AEGIS_BLOCK_SIZE;
 240                 src += AEGIS_BLOCK_SIZE;
 241                 dst += AEGIS_BLOCK_SIZE;
 242         }
 243
 244         if (size > 0) {
 245                 uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
 246                 uint8_t buf[AEGIS_BLOCK_SIZE];
 247                 const void *in = src;
 248                 void *out = dst;
 249                 uint8x16_t m;
 250
 251                 if (__builtin_expect(short_input, 0))
 252                         in = out = memcpy(buf + AEGIS_BLOCK_SIZE - size, src, size);
 253
 254                 m = vqtbl1q_u8(vld1q_u8(in + size - AEGIS_BLOCK_SIZE),
 255                                vld1q_u8(permute + 32 - size));
 256
 257                 st = aegis128_update_neon(st, m);
 258
 259                 vst1q_u8(out + size - AEGIS_BLOCK_SIZE,
 260                          vqtbl1q_u8(m ^ s, vld1q_u8(permute + size)));
 261
 262                 if (__builtin_expect(short_input, 0))
 263                         memcpy(dst, out, size);
 264                 else
 265                         vst1q_u8(out - AEGIS_BLOCK_SIZE, msg);
 266         }
 267
 268         aegis128_save_state_neon(st, state);
 269 }
 270
 271 void crypto_aegis128_decrypt_chunk_neon(void *state, void *dst, const void *src,
 272                                         unsigned int size)
 273 {
 274         struct aegis128_state st = aegis128_load_state_neon(state);
 275         const int short_input = size < AEGIS_BLOCK_SIZE;
 276         uint8x16_t msg;
 277
 278         preload_sbox();
 279
 280         while (size >= AEGIS_BLOCK_SIZE) {
 281                 msg = vld1q_u8(src) ^ st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
 282                 st = aegis128_update_neon(st, msg);
 283                 vst1q_u8(dst, msg);
 284
 285                 size -= AEGIS_BLOCK_SIZE;
 286                 src += AEGIS_BLOCK_SIZE;
 287                 dst += AEGIS_BLOCK_SIZE;
 288         }
 289
 290         if (size > 0) {
 291                 uint8x16_t s = st.v[1] ^ (st.v[2] & st.v[3]) ^ st.v[4];
 292                 uint8_t buf[AEGIS_BLOCK_SIZE];
 293                 const void *in = src;
 294                 void *out = dst;
 295                 uint8x16_t m;
 296
 297                 if (__builtin_expect(short_input, 0))
 298                         in = out = memcpy(buf + AEGIS_BLOCK_SIZE - size, src, size);
 299
 300                 m = s ^ vqtbx1q_u8(s, vld1q_u8(in + size - AEGIS_BLOCK_SIZE),
 301                                    vld1q_u8(permute + 32 - size));
 302
 303                 st = aegis128_update_neon(st, m);
 304
 305                 vst1q_u8(out + size - AEGIS_BLOCK_SIZE,
 306                          vqtbl1q_u8(m, vld1q_u8(permute + size)));
 307
 308                 if (__builtin_expect(short_input, 0))
 309                         memcpy(dst, out, size);
 310                 else
 311                         vst1q_u8(out - AEGIS_BLOCK_SIZE, msg);
 312         }
 313
 314         aegis128_save_state_neon(st, state);
 315 }
 316
 317 int crypto_aegis128_final_neon(void *state, void *tag_xor,
 318                                unsigned int assoclen,
 319                                unsigned int cryptlen,
 320                                unsigned int authsize)
 321 {
 322         struct aegis128_state st = aegis128_load_state_neon(state);
 323         uint8x16_t v;
 324         int i;
 325
 326         preload_sbox();
 327
 328         v = st.v[3] ^ (uint8x16_t)vcombine_u64(vmov_n_u64(8ULL * assoclen),
 329                                                vmov_n_u64(8ULL * cryptlen));
 330
 331         for (i = 0; i < 7; i++)
 332                 st = aegis128_update_neon(st, v);
 333
 334         v = st.v[0] ^ st.v[1] ^ st.v[2] ^ st.v[3] ^ st.v[4];
 335
 336         if (authsize > 0) {
 337                 v = vqtbl1q_u8(~vceqq_u8(v, vld1q_u8(tag_xor)),
 338                                vld1q_u8(permute + authsize));
 339
 340                 return vminvq_s8((int8x16_t)v);
 341         }
 342
 343         vst1q_u8(tag_xor, v);
 344         return 0;
 345 }