1 /* 2 * Modified to interface to the Linux kernel 3 * Copyright (c) 2009, Intel Corporation. 4 * 5 * This program is free software; you can redistribute it and/or modify it 6 * under the terms and conditions of the GNU General Public License, 7 * version 2, as published by the Free Software Foundation. 8 * 9 * This program is distributed in the hope it will be useful, but WITHOUT 10 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or 11 * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for 12 * more details. 13 * 14 * You should have received a copy of the GNU General Public License along with 15 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple 16 * Place - Suite 330, Boston, MA 02111-1307 USA. 17 */ 18 19 /* -------------------------------------------------------------------------- 20 * VMAC and VHASH Implementation by Ted Krovetz (tdk@acm.org) and Wei Dai. 21 * This implementation is herby placed in the public domain. 22 * The authors offers no warranty. Use at your own risk. 23 * Please send bug reports to the authors. 24 * Last modified: 17 APR 08, 1700 PDT 25 * ----------------------------------------------------------------------- */ 26 27 #include <linux/init.h> 28 #include <linux/types.h> 29 #include <linux/crypto.h> 30 #include <linux/scatterlist.h> 31 #include <asm/byteorder.h> 32 #include <crypto/scatterwalk.h> 33 #include <crypto/vmac.h> 34 #include <crypto/internal/hash.h> 35 36 /* 37 * Constants and masks 38 */ 39 #define UINT64_C(x) x##ULL 40 const u64 p64 = UINT64_C(0xfffffffffffffeff); /* 2^64 - 257 prime */ 41 const u64 m62 = UINT64_C(0x3fffffffffffffff); /* 62-bit mask */ 42 const u64 m63 = UINT64_C(0x7fffffffffffffff); /* 63-bit mask */ 43 const u64 m64 = UINT64_C(0xffffffffffffffff); /* 64-bit mask */ 44 const u64 mpoly = UINT64_C(0x1fffffff1fffffff); /* Poly key mask */ 45 46 #ifdef __LITTLE_ENDIAN 47 #define INDEX_HIGH 1 48 #define INDEX_LOW 0 49 #else 50 #define INDEX_HIGH 0 51 #define INDEX_LOW 1 52 #endif 53 54 /* 55 * The following routines are used in this implementation. They are 56 * written via macros to simulate zero-overhead call-by-reference. 57 * 58 * MUL64: 64x64->128-bit multiplication 59 * PMUL64: assumes top bits cleared on inputs 60 * ADD128: 128x128->128-bit addition 61 */ 62 63 #define ADD128(rh, rl, ih, il) \ 64 do { \ 65 u64 _il = (il); \ 66 (rl) += (_il); \ 67 if ((rl) < (_il)) \ 68 (rh)++; \ 69 (rh) += (ih); \ 70 } while (0) 71 72 #define MUL32(i1, i2) ((u64)(u32)(i1)*(u32)(i2)) 73 74 #define PMUL64(rh, rl, i1, i2) /* Assumes m doesn't overflow */ \ 75 do { \ 76 u64 _i1 = (i1), _i2 = (i2); \ 77 u64 m = MUL32(_i1, _i2>>32) + MUL32(_i1>>32, _i2); \ 78 rh = MUL32(_i1>>32, _i2>>32); \ 79 rl = MUL32(_i1, _i2); \ 80 ADD128(rh, rl, (m >> 32), (m << 32)); \ 81 } while (0) 82 83 #define MUL64(rh, rl, i1, i2) \ 84 do { \ 85 u64 _i1 = (i1), _i2 = (i2); \ 86 u64 m1 = MUL32(_i1, _i2>>32); \ 87 u64 m2 = MUL32(_i1>>32, _i2); \ 88 rh = MUL32(_i1>>32, _i2>>32); \ 89 rl = MUL32(_i1, _i2); \ 90 ADD128(rh, rl, (m1 >> 32), (m1 << 32)); \ 91 ADD128(rh, rl, (m2 >> 32), (m2 << 32)); \ 92 } while (0) 93 94 /* 95 * For highest performance the L1 NH and L2 polynomial hashes should be 96 * carefully implemented to take advantage of one's target architechture. 97 * Here these two hash functions are defined multiple time; once for 98 * 64-bit architectures, once for 32-bit SSE2 architectures, and once 99 * for the rest (32-bit) architectures. 100 * For each, nh_16 *must* be defined (works on multiples of 16 bytes). 101 * Optionally, nh_vmac_nhbytes can be defined (for multiples of 102 * VMAC_NHBYTES), and nh_16_2 and nh_vmac_nhbytes_2 (versions that do two 103 * NH computations at once). 104 */ 105 106 #ifdef CONFIG_64BIT 107 108 #define nh_16(mp, kp, nw, rh, rl) \ 109 do { \ 110 int i; u64 th, tl; \ 111 rh = rl = 0; \ 112 for (i = 0; i < nw; i += 2) { \ 113 MUL64(th, tl, le64_to_cpup((mp)+i)+(kp)[i], \ 114 le64_to_cpup((mp)+i+1)+(kp)[i+1]); \ 115 ADD128(rh, rl, th, tl); \ 116 } \ 117 } while (0) 118 119 #define nh_16_2(mp, kp, nw, rh, rl, rh1, rl1) \ 120 do { \ 121 int i; u64 th, tl; \ 122 rh1 = rl1 = rh = rl = 0; \ 123 for (i = 0; i < nw; i += 2) { \ 124 MUL64(th, tl, le64_to_cpup((mp)+i)+(kp)[i], \ 125 le64_to_cpup((mp)+i+1)+(kp)[i+1]); \ 126 ADD128(rh, rl, th, tl); \ 127 MUL64(th, tl, le64_to_cpup((mp)+i)+(kp)[i+2], \ 128 le64_to_cpup((mp)+i+1)+(kp)[i+3]); \ 129 ADD128(rh1, rl1, th, tl); \ 130 } \ 131 } while (0) 132 133 #if (VMAC_NHBYTES >= 64) /* These versions do 64-bytes of message at a time */ 134 #define nh_vmac_nhbytes(mp, kp, nw, rh, rl) \ 135 do { \ 136 int i; u64 th, tl; \ 137 rh = rl = 0; \ 138 for (i = 0; i < nw; i += 8) { \ 139 MUL64(th, tl, le64_to_cpup((mp)+i)+(kp)[i], \ 140 le64_to_cpup((mp)+i+1)+(kp)[i+1]); \ 141 ADD128(rh, rl, th, tl); \ 142 MUL64(th, tl, le64_to_cpup((mp)+i+2)+(kp)[i+2], \ 143 le64_to_cpup((mp)+i+3)+(kp)[i+3]); \ 144 ADD128(rh, rl, th, tl); \ 145 MUL64(th, tl, le64_to_cpup((mp)+i+4)+(kp)[i+4], \ 146 le64_to_cpup((mp)+i+5)+(kp)[i+5]); \ 147 ADD128(rh, rl, th, tl); \ 148 MUL64(th, tl, le64_to_cpup((mp)+i+6)+(kp)[i+6], \ 149 le64_to_cpup((mp)+i+7)+(kp)[i+7]); \ 150 ADD128(rh, rl, th, tl); \ 151 } \ 152 } while (0) 153 154 #define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh1, rl1) \ 155 do { \ 156 int i; u64 th, tl; \ 157 rh1 = rl1 = rh = rl = 0; \ 158 for (i = 0; i < nw; i += 8) { \ 159 MUL64(th, tl, le64_to_cpup((mp)+i)+(kp)[i], \ 160 le64_to_cpup((mp)+i+1)+(kp)[i+1]); \ 161 ADD128(rh, rl, th, tl); \ 162 MUL64(th, tl, le64_to_cpup((mp)+i)+(kp)[i+2], \ 163 le64_to_cpup((mp)+i+1)+(kp)[i+3]); \ 164 ADD128(rh1, rl1, th, tl); \ 165 MUL64(th, tl, le64_to_cpup((mp)+i+2)+(kp)[i+2], \ 166 le64_to_cpup((mp)+i+3)+(kp)[i+3]); \ 167 ADD128(rh, rl, th, tl); \ 168 MUL64(th, tl, le64_to_cpup((mp)+i+2)+(kp)[i+4], \ 169 le64_to_cpup((mp)+i+3)+(kp)[i+5]); \ 170 ADD128(rh1, rl1, th, tl); \ 171 MUL64(th, tl, le64_to_cpup((mp)+i+4)+(kp)[i+4], \ 172 le64_to_cpup((mp)+i+5)+(kp)[i+5]); \ 173 ADD128(rh, rl, th, tl); \ 174 MUL64(th, tl, le64_to_cpup((mp)+i+4)+(kp)[i+6], \ 175 le64_to_cpup((mp)+i+5)+(kp)[i+7]); \ 176 ADD128(rh1, rl1, th, tl); \ 177 MUL64(th, tl, le64_to_cpup((mp)+i+6)+(kp)[i+6], \ 178 le64_to_cpup((mp)+i+7)+(kp)[i+7]); \ 179 ADD128(rh, rl, th, tl); \ 180 MUL64(th, tl, le64_to_cpup((mp)+i+6)+(kp)[i+8], \ 181 le64_to_cpup((mp)+i+7)+(kp)[i+9]); \ 182 ADD128(rh1, rl1, th, tl); \ 183 } \ 184 } while (0) 185 #endif 186 187 #define poly_step(ah, al, kh, kl, mh, ml) \ 188 do { \ 189 u64 t1h, t1l, t2h, t2l, t3h, t3l, z = 0; \ 190 /* compute ab*cd, put bd into result registers */ \ 191 PMUL64(t3h, t3l, al, kh); \ 192 PMUL64(t2h, t2l, ah, kl); \ 193 PMUL64(t1h, t1l, ah, 2*kh); \ 194 PMUL64(ah, al, al, kl); \ 195 /* add 2 * ac to result */ \ 196 ADD128(ah, al, t1h, t1l); \ 197 /* add together ad + bc */ \ 198 ADD128(t2h, t2l, t3h, t3l); \ 199 /* now (ah,al), (t2l,2*t2h) need summing */ \ 200 /* first add the high registers, carrying into t2h */ \ 201 ADD128(t2h, ah, z, t2l); \ 202 /* double t2h and add top bit of ah */ \ 203 t2h = 2 * t2h + (ah >> 63); \ 204 ah &= m63; \ 205 /* now add the low registers */ \ 206 ADD128(ah, al, mh, ml); \ 207 ADD128(ah, al, z, t2h); \ 208 } while (0) 209 210 #else /* ! CONFIG_64BIT */ 211 212 #ifndef nh_16 213 #define nh_16(mp, kp, nw, rh, rl) \ 214 do { \ 215 u64 t1, t2, m1, m2, t; \ 216 int i; \ 217 rh = rl = t = 0; \ 218 for (i = 0; i < nw; i += 2) { \ 219 t1 = le64_to_cpup(mp+i) + kp[i]; \ 220 t2 = le64_to_cpup(mp+i+1) + kp[i+1]; \ 221 m2 = MUL32(t1 >> 32, t2); \ 222 m1 = MUL32(t1, t2 >> 32); \ 223 ADD128(rh, rl, MUL32(t1 >> 32, t2 >> 32), \ 224 MUL32(t1, t2)); \ 225 rh += (u64)(u32)(m1 >> 32) \ 226 + (u32)(m2 >> 32); \ 227 t += (u64)(u32)m1 + (u32)m2; \ 228 } \ 229 ADD128(rh, rl, (t >> 32), (t << 32)); \ 230 } while (0) 231 #endif 232 233 static void poly_step_func(u64 *ahi, u64 *alo, 234 const u64 *kh, const u64 *kl, 235 const u64 *mh, const u64 *ml) 236 { 237 #define a0 (*(((u32 *)alo)+INDEX_LOW)) 238 #define a1 (*(((u32 *)alo)+INDEX_HIGH)) 239 #define a2 (*(((u32 *)ahi)+INDEX_LOW)) 240 #define a3 (*(((u32 *)ahi)+INDEX_HIGH)) 241 #define k0 (*(((u32 *)kl)+INDEX_LOW)) 242 #define k1 (*(((u32 *)kl)+INDEX_HIGH)) 243 #define k2 (*(((u32 *)kh)+INDEX_LOW)) 244 #define k3 (*(((u32 *)kh)+INDEX_HIGH)) 245 246 u64 p, q, t; 247 u32 t2; 248 249 p = MUL32(a3, k3); 250 p += p; 251 p += *(u64 *)mh; 252 p += MUL32(a0, k2); 253 p += MUL32(a1, k1); 254 p += MUL32(a2, k0); 255 t = (u32)(p); 256 p >>= 32; 257 p += MUL32(a0, k3); 258 p += MUL32(a1, k2); 259 p += MUL32(a2, k1); 260 p += MUL32(a3, k0); 261 t |= ((u64)((u32)p & 0x7fffffff)) << 32; 262 p >>= 31; 263 p += (u64)(((u32 *)ml)[INDEX_LOW]); 264 p += MUL32(a0, k0); 265 q = MUL32(a1, k3); 266 q += MUL32(a2, k2); 267 q += MUL32(a3, k1); 268 q += q; 269 p += q; 270 t2 = (u32)(p); 271 p >>= 32; 272 p += (u64)(((u32 *)ml)[INDEX_HIGH]); 273 p += MUL32(a0, k1); 274 p += MUL32(a1, k0); 275 q = MUL32(a2, k3); 276 q += MUL32(a3, k2); 277 q += q; 278 p += q; 279 *(u64 *)(alo) = (p << 32) | t2; 280 p >>= 32; 281 *(u64 *)(ahi) = p + t; 282 283 #undef a0 284 #undef a1 285 #undef a2 286 #undef a3 287 #undef k0 288 #undef k1 289 #undef k2 290 #undef k3 291 } 292 293 #define poly_step(ah, al, kh, kl, mh, ml) \ 294 poly_step_func(&(ah), &(al), &(kh), &(kl), &(mh), &(ml)) 295 296 #endif /* end of specialized NH and poly definitions */ 297 298 /* At least nh_16 is defined. Defined others as needed here */ 299 #ifndef nh_16_2 300 #define nh_16_2(mp, kp, nw, rh, rl, rh2, rl2) \ 301 do { \ 302 nh_16(mp, kp, nw, rh, rl); \ 303 nh_16(mp, ((kp)+2), nw, rh2, rl2); \ 304 } while (0) 305 #endif 306 #ifndef nh_vmac_nhbytes 307 #define nh_vmac_nhbytes(mp, kp, nw, rh, rl) \ 308 nh_16(mp, kp, nw, rh, rl) 309 #endif 310 #ifndef nh_vmac_nhbytes_2 311 #define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh2, rl2) \ 312 do { \ 313 nh_vmac_nhbytes(mp, kp, nw, rh, rl); \ 314 nh_vmac_nhbytes(mp, ((kp)+2), nw, rh2, rl2); \ 315 } while (0) 316 #endif 317 318 static void vhash_abort(struct vmac_ctx *ctx) 319 { 320 ctx->polytmp[0] = ctx->polykey[0] ; 321 ctx->polytmp[1] = ctx->polykey[1] ; 322 ctx->first_block_processed = 0; 323 } 324 325 static u64 l3hash(u64 p1, u64 p2, 326 u64 k1, u64 k2, u64 len) 327 { 328 u64 rh, rl, t, z = 0; 329 330 /* fully reduce (p1,p2)+(len,0) mod p127 */ 331 t = p1 >> 63; 332 p1 &= m63; 333 ADD128(p1, p2, len, t); 334 /* At this point, (p1,p2) is at most 2^127+(len<<64) */ 335 t = (p1 > m63) + ((p1 == m63) && (p2 == m64)); 336 ADD128(p1, p2, z, t); 337 p1 &= m63; 338 339 /* compute (p1,p2)/(2^64-2^32) and (p1,p2)%(2^64-2^32) */ 340 t = p1 + (p2 >> 32); 341 t += (t >> 32); 342 t += (u32)t > 0xfffffffeu; 343 p1 += (t >> 32); 344 p2 += (p1 << 32); 345 346 /* compute (p1+k1)%p64 and (p2+k2)%p64 */ 347 p1 += k1; 348 p1 += (0 - (p1 < k1)) & 257; 349 p2 += k2; 350 p2 += (0 - (p2 < k2)) & 257; 351 352 /* compute (p1+k1)*(p2+k2)%p64 */ 353 MUL64(rh, rl, p1, p2); 354 t = rh >> 56; 355 ADD128(t, rl, z, rh); 356 rh <<= 8; 357 ADD128(t, rl, z, rh); 358 t += t << 8; 359 rl += t; 360 rl += (0 - (rl < t)) & 257; 361 rl += (0 - (rl > p64-1)) & 257; 362 return rl; 363 } 364 365 static void vhash_update(const unsigned char *m, 366 unsigned int mbytes, /* Pos multiple of VMAC_NHBYTES */ 367 struct vmac_ctx *ctx) 368 { 369 u64 rh, rl, *mptr; 370 const u64 *kptr = (u64 *)ctx->nhkey; 371 int i; 372 u64 ch, cl; 373 u64 pkh = ctx->polykey[0]; 374 u64 pkl = ctx->polykey[1]; 375 376 mptr = (u64 *)m; 377 i = mbytes / VMAC_NHBYTES; /* Must be non-zero */ 378 379 ch = ctx->polytmp[0]; 380 cl = ctx->polytmp[1]; 381 382 if (!ctx->first_block_processed) { 383 ctx->first_block_processed = 1; 384 nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl); 385 rh &= m62; 386 ADD128(ch, cl, rh, rl); 387 mptr += (VMAC_NHBYTES/sizeof(u64)); 388 i--; 389 } 390 391 while (i--) { 392 nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl); 393 rh &= m62; 394 poly_step(ch, cl, pkh, pkl, rh, rl); 395 mptr += (VMAC_NHBYTES/sizeof(u64)); 396 } 397 398 ctx->polytmp[0] = ch; 399 ctx->polytmp[1] = cl; 400 } 401 402 static u64 vhash(unsigned char m[], unsigned int mbytes, 403 u64 *tagl, struct vmac_ctx *ctx) 404 { 405 u64 rh, rl, *mptr; 406 const u64 *kptr = (u64 *)ctx->nhkey; 407 int i, remaining; 408 u64 ch, cl; 409 u64 pkh = ctx->polykey[0]; 410 u64 pkl = ctx->polykey[1]; 411 412 mptr = (u64 *)m; 413 i = mbytes / VMAC_NHBYTES; 414 remaining = mbytes % VMAC_NHBYTES; 415 416 if (ctx->first_block_processed) { 417 ch = ctx->polytmp[0]; 418 cl = ctx->polytmp[1]; 419 } else if (i) { 420 nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, ch, cl); 421 ch &= m62; 422 ADD128(ch, cl, pkh, pkl); 423 mptr += (VMAC_NHBYTES/sizeof(u64)); 424 i--; 425 } else if (remaining) { 426 nh_16(mptr, kptr, 2*((remaining+15)/16), ch, cl); 427 ch &= m62; 428 ADD128(ch, cl, pkh, pkl); 429 mptr += (VMAC_NHBYTES/sizeof(u64)); 430 goto do_l3; 431 } else {/* Empty String */ 432 ch = pkh; cl = pkl; 433 goto do_l3; 434 } 435 436 while (i--) { 437 nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl); 438 rh &= m62; 439 poly_step(ch, cl, pkh, pkl, rh, rl); 440 mptr += (VMAC_NHBYTES/sizeof(u64)); 441 } 442 if (remaining) { 443 nh_16(mptr, kptr, 2*((remaining+15)/16), rh, rl); 444 rh &= m62; 445 poly_step(ch, cl, pkh, pkl, rh, rl); 446 } 447 448 do_l3: 449 vhash_abort(ctx); 450 remaining *= 8; 451 return l3hash(ch, cl, ctx->l3key[0], ctx->l3key[1], remaining); 452 } 453 454 static u64 vmac(unsigned char m[], unsigned int mbytes, 455 unsigned char n[16], u64 *tagl, 456 struct vmac_ctx_t *ctx) 457 { 458 u64 *in_n, *out_p; 459 u64 p, h; 460 int i; 461 462 in_n = ctx->__vmac_ctx.cached_nonce; 463 out_p = ctx->__vmac_ctx.cached_aes; 464 465 i = n[15] & 1; 466 if ((*(u64 *)(n+8) != in_n[1]) || (*(u64 *)(n) != in_n[0])) { 467 in_n[0] = *(u64 *)(n); 468 in_n[1] = *(u64 *)(n+8); 469 ((unsigned char *)in_n)[15] &= 0xFE; 470 crypto_cipher_encrypt_one(ctx->child, 471 (unsigned char *)out_p, (unsigned char *)in_n); 472 473 ((unsigned char *)in_n)[15] |= (unsigned char)(1-i); 474 } 475 p = be64_to_cpup(out_p + i); 476 h = vhash(m, mbytes, (u64 *)0, &ctx->__vmac_ctx); 477 return p + h; 478 } 479 480 static int vmac_set_key(unsigned char user_key[], struct vmac_ctx_t *ctx) 481 { 482 u64 in[2] = {0}, out[2]; 483 unsigned i; 484 int err = 0; 485 486 err = crypto_cipher_setkey(ctx->child, user_key, VMAC_KEY_LEN); 487 if (err) 488 return err; 489 490 /* Fill nh key */ 491 ((unsigned char *)in)[0] = 0x80; 492 for (i = 0; i < sizeof(ctx->__vmac_ctx.nhkey)/8; i += 2) { 493 crypto_cipher_encrypt_one(ctx->child, 494 (unsigned char *)out, (unsigned char *)in); 495 ctx->__vmac_ctx.nhkey[i] = be64_to_cpup(out); 496 ctx->__vmac_ctx.nhkey[i+1] = be64_to_cpup(out+1); 497 ((unsigned char *)in)[15] += 1; 498 } 499 500 /* Fill poly key */ 501 ((unsigned char *)in)[0] = 0xC0; 502 in[1] = 0; 503 for (i = 0; i < sizeof(ctx->__vmac_ctx.polykey)/8; i += 2) { 504 crypto_cipher_encrypt_one(ctx->child, 505 (unsigned char *)out, (unsigned char *)in); 506 ctx->__vmac_ctx.polytmp[i] = 507 ctx->__vmac_ctx.polykey[i] = 508 be64_to_cpup(out) & mpoly; 509 ctx->__vmac_ctx.polytmp[i+1] = 510 ctx->__vmac_ctx.polykey[i+1] = 511 be64_to_cpup(out+1) & mpoly; 512 ((unsigned char *)in)[15] += 1; 513 } 514 515 /* Fill ip key */ 516 ((unsigned char *)in)[0] = 0xE0; 517 in[1] = 0; 518 for (i = 0; i < sizeof(ctx->__vmac_ctx.l3key)/8; i += 2) { 519 do { 520 crypto_cipher_encrypt_one(ctx->child, 521 (unsigned char *)out, (unsigned char *)in); 522 ctx->__vmac_ctx.l3key[i] = be64_to_cpup(out); 523 ctx->__vmac_ctx.l3key[i+1] = be64_to_cpup(out+1); 524 ((unsigned char *)in)[15] += 1; 525 } while (ctx->__vmac_ctx.l3key[i] >= p64 526 || ctx->__vmac_ctx.l3key[i+1] >= p64); 527 } 528 529 /* Invalidate nonce/aes cache and reset other elements */ 530 ctx->__vmac_ctx.cached_nonce[0] = (u64)-1; /* Ensure illegal nonce */ 531 ctx->__vmac_ctx.cached_nonce[1] = (u64)0; /* Ensure illegal nonce */ 532 ctx->__vmac_ctx.first_block_processed = 0; 533 534 return err; 535 } 536 537 static int vmac_setkey(struct crypto_shash *parent, 538 const u8 *key, unsigned int keylen) 539 { 540 struct vmac_ctx_t *ctx = crypto_shash_ctx(parent); 541 542 if (keylen != VMAC_KEY_LEN) { 543 crypto_shash_set_flags(parent, CRYPTO_TFM_RES_BAD_KEY_LEN); 544 return -EINVAL; 545 } 546 547 return vmac_set_key((u8 *)key, ctx); 548 } 549 550 static int vmac_init(struct shash_desc *pdesc) 551 { 552 struct crypto_shash *parent = pdesc->tfm; 553 struct vmac_ctx_t *ctx = crypto_shash_ctx(parent); 554 555 memset(&ctx->__vmac_ctx, 0, sizeof(struct vmac_ctx)); 556 return 0; 557 } 558 559 static int vmac_update(struct shash_desc *pdesc, const u8 *p, 560 unsigned int len) 561 { 562 struct crypto_shash *parent = pdesc->tfm; 563 struct vmac_ctx_t *ctx = crypto_shash_ctx(parent); 564 565 vhash_update(p, len, &ctx->__vmac_ctx); 566 567 return 0; 568 } 569 570 static int vmac_final(struct shash_desc *pdesc, u8 *out) 571 { 572 struct crypto_shash *parent = pdesc->tfm; 573 struct vmac_ctx_t *ctx = crypto_shash_ctx(parent); 574 vmac_t mac; 575 u8 nonce[16] = {}; 576 577 mac = vmac(NULL, 0, nonce, NULL, ctx); 578 memcpy(out, &mac, sizeof(vmac_t)); 579 memset(&mac, 0, sizeof(vmac_t)); 580 memset(&ctx->__vmac_ctx, 0, sizeof(struct vmac_ctx)); 581 return 0; 582 } 583 584 static int vmac_init_tfm(struct crypto_tfm *tfm) 585 { 586 struct crypto_cipher *cipher; 587 struct crypto_instance *inst = (void *)tfm->__crt_alg; 588 struct crypto_spawn *spawn = crypto_instance_ctx(inst); 589 struct vmac_ctx_t *ctx = crypto_tfm_ctx(tfm); 590 591 cipher = crypto_spawn_cipher(spawn); 592 if (IS_ERR(cipher)) 593 return PTR_ERR(cipher); 594 595 ctx->child = cipher; 596 return 0; 597 } 598 599 static void vmac_exit_tfm(struct crypto_tfm *tfm) 600 { 601 struct vmac_ctx_t *ctx = crypto_tfm_ctx(tfm); 602 crypto_free_cipher(ctx->child); 603 } 604 605 static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb) 606 { 607 struct shash_instance *inst; 608 struct crypto_alg *alg; 609 int err; 610 611 err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH); 612 if (err) 613 return err; 614 615 alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER, 616 CRYPTO_ALG_TYPE_MASK); 617 if (IS_ERR(alg)) 618 return PTR_ERR(alg); 619 620 inst = shash_alloc_instance("vmac", alg); 621 err = PTR_ERR(inst); 622 if (IS_ERR(inst)) 623 goto out_put_alg; 624 625 err = crypto_init_spawn(shash_instance_ctx(inst), alg, 626 shash_crypto_instance(inst), 627 CRYPTO_ALG_TYPE_MASK); 628 if (err) 629 goto out_free_inst; 630 631 inst->alg.base.cra_priority = alg->cra_priority; 632 inst->alg.base.cra_blocksize = alg->cra_blocksize; 633 inst->alg.base.cra_alignmask = alg->cra_alignmask; 634 635 inst->alg.digestsize = sizeof(vmac_t); 636 inst->alg.base.cra_ctxsize = sizeof(struct vmac_ctx_t); 637 inst->alg.base.cra_init = vmac_init_tfm; 638 inst->alg.base.cra_exit = vmac_exit_tfm; 639 640 inst->alg.init = vmac_init; 641 inst->alg.update = vmac_update; 642 inst->alg.final = vmac_final; 643 inst->alg.setkey = vmac_setkey; 644 645 err = shash_register_instance(tmpl, inst); 646 if (err) { 647 out_free_inst: 648 shash_free_instance(shash_crypto_instance(inst)); 649 } 650 651 out_put_alg: 652 crypto_mod_put(alg); 653 return err; 654 } 655 656 static struct crypto_template vmac_tmpl = { 657 .name = "vmac", 658 .create = vmac_create, 659 .free = shash_free_instance, 660 .module = THIS_MODULE, 661 }; 662 663 static int __init vmac_module_init(void) 664 { 665 return crypto_register_template(&vmac_tmpl); 666 } 667 668 static void __exit vmac_module_exit(void) 669 { 670 crypto_unregister_template(&vmac_tmpl); 671 } 672 673 module_init(vmac_module_init); 674 module_exit(vmac_module_exit); 675 676 MODULE_LICENSE("GPL"); 677 MODULE_DESCRIPTION("VMAC hash algorithm"); 678 679