linux/crypto/vmac.c
<<
>>
Prefs
   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/module.h>
  31#include <linux/scatterlist.h>
  32#include <asm/byteorder.h>
  33#include <crypto/scatterwalk.h>
  34#include <crypto/vmac.h>
  35#include <crypto/internal/hash.h>
  36
  37/*
  38 * Constants and masks
  39 */
  40#define UINT64_C(x) x##ULL
  41static const u64 p64   = UINT64_C(0xfffffffffffffeff);  /* 2^64 - 257 prime  */
  42static const u64 m62   = UINT64_C(0x3fffffffffffffff);  /* 62-bit mask       */
  43static const u64 m63   = UINT64_C(0x7fffffffffffffff);  /* 63-bit mask       */
  44static const u64 m64   = UINT64_C(0xffffffffffffffff);  /* 64-bit mask       */
  45static const u64 mpoly = UINT64_C(0x1fffffff1fffffff);  /* Poly key mask     */
  46
  47#define pe64_to_cpup le64_to_cpup               /* Prefer little endian */
  48
  49#ifdef __LITTLE_ENDIAN
  50#define INDEX_HIGH 1
  51#define INDEX_LOW 0
  52#else
  53#define INDEX_HIGH 0
  54#define INDEX_LOW 1
  55#endif
  56
  57/*
  58 * The following routines are used in this implementation. They are
  59 * written via macros to simulate zero-overhead call-by-reference.
  60 *
  61 * MUL64: 64x64->128-bit multiplication
  62 * PMUL64: assumes top bits cleared on inputs
  63 * ADD128: 128x128->128-bit addition
  64 */
  65
  66#define ADD128(rh, rl, ih, il)                                          \
  67        do {                                                            \
  68                u64 _il = (il);                                         \
  69                (rl) += (_il);                                          \
  70                if ((rl) < (_il))                                       \
  71                        (rh)++;                                         \
  72                (rh) += (ih);                                           \
  73        } while (0)
  74
  75#define MUL32(i1, i2)   ((u64)(u32)(i1)*(u32)(i2))
  76
  77#define PMUL64(rh, rl, i1, i2)  /* Assumes m doesn't overflow */        \
  78        do {                                                            \
  79                u64 _i1 = (i1), _i2 = (i2);                             \
  80                u64 m = MUL32(_i1, _i2>>32) + MUL32(_i1>>32, _i2);      \
  81                rh = MUL32(_i1>>32, _i2>>32);                           \
  82                rl = MUL32(_i1, _i2);                                   \
  83                ADD128(rh, rl, (m >> 32), (m << 32));                   \
  84        } while (0)
  85
  86#define MUL64(rh, rl, i1, i2)                                           \
  87        do {                                                            \
  88                u64 _i1 = (i1), _i2 = (i2);                             \
  89                u64 m1 = MUL32(_i1, _i2>>32);                           \
  90                u64 m2 = MUL32(_i1>>32, _i2);                           \
  91                rh = MUL32(_i1>>32, _i2>>32);                           \
  92                rl = MUL32(_i1, _i2);                                   \
  93                ADD128(rh, rl, (m1 >> 32), (m1 << 32));                 \
  94                ADD128(rh, rl, (m2 >> 32), (m2 << 32));                 \
  95        } while (0)
  96
  97/*
  98 * For highest performance the L1 NH and L2 polynomial hashes should be
  99 * carefully implemented to take advantage of one's target architecture.
 100 * Here these two hash functions are defined multiple time; once for
 101 * 64-bit architectures, once for 32-bit SSE2 architectures, and once
 102 * for the rest (32-bit) architectures.
 103 * For each, nh_16 *must* be defined (works on multiples of 16 bytes).
 104 * Optionally, nh_vmac_nhbytes can be defined (for multiples of
 105 * VMAC_NHBYTES), and nh_16_2 and nh_vmac_nhbytes_2 (versions that do two
 106 * NH computations at once).
 107 */
 108
 109#ifdef CONFIG_64BIT
 110
 111#define nh_16(mp, kp, nw, rh, rl)                                       \
 112        do {                                                            \
 113                int i; u64 th, tl;                                      \
 114                rh = rl = 0;                                            \
 115                for (i = 0; i < nw; i += 2) {                           \
 116                        MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],     \
 117                                pe64_to_cpup((mp)+i+1)+(kp)[i+1]);      \
 118                        ADD128(rh, rl, th, tl);                         \
 119                }                                                       \
 120        } while (0)
 121
 122#define nh_16_2(mp, kp, nw, rh, rl, rh1, rl1)                           \
 123        do {                                                            \
 124                int i; u64 th, tl;                                      \
 125                rh1 = rl1 = rh = rl = 0;                                \
 126                for (i = 0; i < nw; i += 2) {                           \
 127                        MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],     \
 128                                pe64_to_cpup((mp)+i+1)+(kp)[i+1]);      \
 129                        ADD128(rh, rl, th, tl);                         \
 130                        MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i+2],   \
 131                                pe64_to_cpup((mp)+i+1)+(kp)[i+3]);      \
 132                        ADD128(rh1, rl1, th, tl);                       \
 133                }                                                       \
 134        } while (0)
 135
 136#if (VMAC_NHBYTES >= 64) /* These versions do 64-bytes of message at a time */
 137#define nh_vmac_nhbytes(mp, kp, nw, rh, rl)                             \
 138        do {                                                            \
 139                int i; u64 th, tl;                                      \
 140                rh = rl = 0;                                            \
 141                for (i = 0; i < nw; i += 8) {                           \
 142                        MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],     \
 143                                pe64_to_cpup((mp)+i+1)+(kp)[i+1]);      \
 144                        ADD128(rh, rl, th, tl);                         \
 145                        MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+2], \
 146                                pe64_to_cpup((mp)+i+3)+(kp)[i+3]);      \
 147                        ADD128(rh, rl, th, tl);                         \
 148                        MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+4], \
 149                                pe64_to_cpup((mp)+i+5)+(kp)[i+5]);      \
 150                        ADD128(rh, rl, th, tl);                         \
 151                        MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+6], \
 152                                pe64_to_cpup((mp)+i+7)+(kp)[i+7]);      \
 153                        ADD128(rh, rl, th, tl);                         \
 154                }                                                       \
 155        } while (0)
 156
 157#define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh1, rl1)                 \
 158        do {                                                            \
 159                int i; u64 th, tl;                                      \
 160                rh1 = rl1 = rh = rl = 0;                                \
 161                for (i = 0; i < nw; i += 8) {                           \
 162                        MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],     \
 163                                pe64_to_cpup((mp)+i+1)+(kp)[i+1]);      \
 164                        ADD128(rh, rl, th, tl);                         \
 165                        MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i+2],   \
 166                                pe64_to_cpup((mp)+i+1)+(kp)[i+3]);      \
 167                        ADD128(rh1, rl1, th, tl);                       \
 168                        MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+2], \
 169                                pe64_to_cpup((mp)+i+3)+(kp)[i+3]);      \
 170                        ADD128(rh, rl, th, tl);                         \
 171                        MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+4], \
 172                                pe64_to_cpup((mp)+i+3)+(kp)[i+5]);      \
 173                        ADD128(rh1, rl1, th, tl);                       \
 174                        MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+4], \
 175                                pe64_to_cpup((mp)+i+5)+(kp)[i+5]);      \
 176                        ADD128(rh, rl, th, tl);                         \
 177                        MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+6], \
 178                                pe64_to_cpup((mp)+i+5)+(kp)[i+7]);      \
 179                        ADD128(rh1, rl1, th, tl);                       \
 180                        MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+6], \
 181                                pe64_to_cpup((mp)+i+7)+(kp)[i+7]);      \
 182                        ADD128(rh, rl, th, tl);                         \
 183                        MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+8], \
 184                                pe64_to_cpup((mp)+i+7)+(kp)[i+9]);      \
 185                        ADD128(rh1, rl1, th, tl);                       \
 186                }                                                       \
 187        } while (0)
 188#endif
 189
 190#define poly_step(ah, al, kh, kl, mh, ml)                               \
 191        do {                                                            \
 192                u64 t1h, t1l, t2h, t2l, t3h, t3l, z = 0;                \
 193                /* compute ab*cd, put bd into result registers */       \
 194                PMUL64(t3h, t3l, al, kh);                               \
 195                PMUL64(t2h, t2l, ah, kl);                               \
 196                PMUL64(t1h, t1l, ah, 2*kh);                             \
 197                PMUL64(ah, al, al, kl);                                 \
 198                /* add 2 * ac to result */                              \
 199                ADD128(ah, al, t1h, t1l);                               \
 200                /* add together ad + bc */                              \
 201                ADD128(t2h, t2l, t3h, t3l);                             \
 202                /* now (ah,al), (t2l,2*t2h) need summing */             \
 203                /* first add the high registers, carrying into t2h */   \
 204                ADD128(t2h, ah, z, t2l);                                \
 205                /* double t2h and add top bit of ah */                  \
 206                t2h = 2 * t2h + (ah >> 63);                             \
 207                ah &= m63;                                              \
 208                /* now add the low registers */                         \
 209                ADD128(ah, al, mh, ml);                                 \
 210                ADD128(ah, al, z, t2h);                                 \
 211        } while (0)
 212
 213#else /* ! CONFIG_64BIT */
 214
 215#ifndef nh_16
 216#define nh_16(mp, kp, nw, rh, rl)                                       \
 217        do {                                                            \
 218                u64 t1, t2, m1, m2, t;                                  \
 219                int i;                                                  \
 220                rh = rl = t = 0;                                        \
 221                for (i = 0; i < nw; i += 2)  {                          \
 222                        t1 = pe64_to_cpup(mp+i) + kp[i];                \
 223                        t2 = pe64_to_cpup(mp+i+1) + kp[i+1];            \
 224                        m2 = MUL32(t1 >> 32, t2);                       \
 225                        m1 = MUL32(t1, t2 >> 32);                       \
 226                        ADD128(rh, rl, MUL32(t1 >> 32, t2 >> 32),       \
 227                                MUL32(t1, t2));                         \
 228                        rh += (u64)(u32)(m1 >> 32)                      \
 229                                + (u32)(m2 >> 32);                      \
 230                        t += (u64)(u32)m1 + (u32)m2;                    \
 231                }                                                       \
 232                ADD128(rh, rl, (t >> 32), (t << 32));                   \
 233        } while (0)
 234#endif
 235
 236static void poly_step_func(u64 *ahi, u64 *alo,
 237                        const u64 *kh, const u64 *kl,
 238                        const u64 *mh, const u64 *ml)
 239{
 240#define a0 (*(((u32 *)alo)+INDEX_LOW))
 241#define a1 (*(((u32 *)alo)+INDEX_HIGH))
 242#define a2 (*(((u32 *)ahi)+INDEX_LOW))
 243#define a3 (*(((u32 *)ahi)+INDEX_HIGH))
 244#define k0 (*(((u32 *)kl)+INDEX_LOW))
 245#define k1 (*(((u32 *)kl)+INDEX_HIGH))
 246#define k2 (*(((u32 *)kh)+INDEX_LOW))
 247#define k3 (*(((u32 *)kh)+INDEX_HIGH))
 248
 249        u64 p, q, t;
 250        u32 t2;
 251
 252        p = MUL32(a3, k3);
 253        p += p;
 254        p += *(u64 *)mh;
 255        p += MUL32(a0, k2);
 256        p += MUL32(a1, k1);
 257        p += MUL32(a2, k0);
 258        t = (u32)(p);
 259        p >>= 32;
 260        p += MUL32(a0, k3);
 261        p += MUL32(a1, k2);
 262        p += MUL32(a2, k1);
 263        p += MUL32(a3, k0);
 264        t |= ((u64)((u32)p & 0x7fffffff)) << 32;
 265        p >>= 31;
 266        p += (u64)(((u32 *)ml)[INDEX_LOW]);
 267        p += MUL32(a0, k0);
 268        q =  MUL32(a1, k3);
 269        q += MUL32(a2, k2);
 270        q += MUL32(a3, k1);
 271        q += q;
 272        p += q;
 273        t2 = (u32)(p);
 274        p >>= 32;
 275        p += (u64)(((u32 *)ml)[INDEX_HIGH]);
 276        p += MUL32(a0, k1);
 277        p += MUL32(a1, k0);
 278        q =  MUL32(a2, k3);
 279        q += MUL32(a3, k2);
 280        q += q;
 281        p += q;
 282        *(u64 *)(alo) = (p << 32) | t2;
 283        p >>= 32;
 284        *(u64 *)(ahi) = p + t;
 285
 286#undef a0
 287#undef a1
 288#undef a2
 289#undef a3
 290#undef k0
 291#undef k1
 292#undef k2
 293#undef k3
 294}
 295
 296#define poly_step(ah, al, kh, kl, mh, ml)                               \
 297        poly_step_func(&(ah), &(al), &(kh), &(kl), &(mh), &(ml))
 298
 299#endif  /* end of specialized NH and poly definitions */
 300
 301/* At least nh_16 is defined. Defined others as needed here */
 302#ifndef nh_16_2
 303#define nh_16_2(mp, kp, nw, rh, rl, rh2, rl2)                           \
 304        do {                                                            \
 305                nh_16(mp, kp, nw, rh, rl);                              \
 306                nh_16(mp, ((kp)+2), nw, rh2, rl2);                      \
 307        } while (0)
 308#endif
 309#ifndef nh_vmac_nhbytes
 310#define nh_vmac_nhbytes(mp, kp, nw, rh, rl)                             \
 311        nh_16(mp, kp, nw, rh, rl)
 312#endif
 313#ifndef nh_vmac_nhbytes_2
 314#define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh2, rl2)                 \
 315        do {                                                            \
 316                nh_vmac_nhbytes(mp, kp, nw, rh, rl);                    \
 317                nh_vmac_nhbytes(mp, ((kp)+2), nw, rh2, rl2);            \
 318        } while (0)
 319#endif
 320
 321static void vhash_abort(struct vmac_ctx *ctx)
 322{
 323        ctx->polytmp[0] = ctx->polykey[0] ;
 324        ctx->polytmp[1] = ctx->polykey[1] ;
 325        ctx->first_block_processed = 0;
 326}
 327
 328static u64 l3hash(u64 p1, u64 p2, u64 k1, u64 k2, u64 len)
 329{
 330        u64 rh, rl, t, z = 0;
 331
 332        /* fully reduce (p1,p2)+(len,0) mod p127 */
 333        t = p1 >> 63;
 334        p1 &= m63;
 335        ADD128(p1, p2, len, t);
 336        /* At this point, (p1,p2) is at most 2^127+(len<<64) */
 337        t = (p1 > m63) + ((p1 == m63) && (p2 == m64));
 338        ADD128(p1, p2, z, t);
 339        p1 &= m63;
 340
 341        /* compute (p1,p2)/(2^64-2^32) and (p1,p2)%(2^64-2^32) */
 342        t = p1 + (p2 >> 32);
 343        t += (t >> 32);
 344        t += (u32)t > 0xfffffffeu;
 345        p1 += (t >> 32);
 346        p2 += (p1 << 32);
 347
 348        /* compute (p1+k1)%p64 and (p2+k2)%p64 */
 349        p1 += k1;
 350        p1 += (0 - (p1 < k1)) & 257;
 351        p2 += k2;
 352        p2 += (0 - (p2 < k2)) & 257;
 353
 354        /* compute (p1+k1)*(p2+k2)%p64 */
 355        MUL64(rh, rl, p1, p2);
 356        t = rh >> 56;
 357        ADD128(t, rl, z, rh);
 358        rh <<= 8;
 359        ADD128(t, rl, z, rh);
 360        t += t << 8;
 361        rl += t;
 362        rl += (0 - (rl < t)) & 257;
 363        rl += (0 - (rl > p64-1)) & 257;
 364        return rl;
 365}
 366
 367static void vhash_update(const unsigned char *m,
 368                        unsigned int mbytes, /* Pos multiple of VMAC_NHBYTES */
 369                        struct vmac_ctx *ctx)
 370{
 371        u64 rh, rl, *mptr;
 372        const u64 *kptr = (u64 *)ctx->nhkey;
 373        int i;
 374        u64 ch, cl;
 375        u64 pkh = ctx->polykey[0];
 376        u64 pkl = ctx->polykey[1];
 377
 378        if (!mbytes)
 379                return;
 380
 381        BUG_ON(mbytes % VMAC_NHBYTES);
 382
 383        mptr = (u64 *)m;
 384        i = mbytes / VMAC_NHBYTES;  /* Must be non-zero */
 385
 386        ch = ctx->polytmp[0];
 387        cl = ctx->polytmp[1];
 388
 389        if (!ctx->first_block_processed) {
 390                ctx->first_block_processed = 1;
 391                nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl);
 392                rh &= m62;
 393                ADD128(ch, cl, rh, rl);
 394                mptr += (VMAC_NHBYTES/sizeof(u64));
 395                i--;
 396        }
 397
 398        while (i--) {
 399                nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl);
 400                rh &= m62;
 401                poly_step(ch, cl, pkh, pkl, rh, rl);
 402                mptr += (VMAC_NHBYTES/sizeof(u64));
 403        }
 404
 405        ctx->polytmp[0] = ch;
 406        ctx->polytmp[1] = cl;
 407}
 408
 409static u64 vhash(unsigned char m[], unsigned int mbytes,
 410                        u64 *tagl, struct vmac_ctx *ctx)
 411{
 412        u64 rh, rl, *mptr;
 413        const u64 *kptr = (u64 *)ctx->nhkey;
 414        int i, remaining;
 415        u64 ch, cl;
 416        u64 pkh = ctx->polykey[0];
 417        u64 pkl = ctx->polykey[1];
 418
 419        mptr = (u64 *)m;
 420        i = mbytes / VMAC_NHBYTES;
 421        remaining = mbytes % VMAC_NHBYTES;
 422
 423        if (ctx->first_block_processed) {
 424                ch = ctx->polytmp[0];
 425                cl = ctx->polytmp[1];
 426        } else if (i) {
 427                nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, ch, cl);
 428                ch &= m62;
 429                ADD128(ch, cl, pkh, pkl);
 430                mptr += (VMAC_NHBYTES/sizeof(u64));
 431                i--;
 432        } else if (remaining) {
 433                nh_16(mptr, kptr, 2*((remaining+15)/16), ch, cl);
 434                ch &= m62;
 435                ADD128(ch, cl, pkh, pkl);
 436                mptr += (VMAC_NHBYTES/sizeof(u64));
 437                goto do_l3;
 438        } else {/* Empty String */
 439                ch = pkh; cl = pkl;
 440                goto do_l3;
 441        }
 442
 443        while (i--) {
 444                nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl);
 445                rh &= m62;
 446                poly_step(ch, cl, pkh, pkl, rh, rl);
 447                mptr += (VMAC_NHBYTES/sizeof(u64));
 448        }
 449        if (remaining) {
 450                nh_16(mptr, kptr, 2*((remaining+15)/16), rh, rl);
 451                rh &= m62;
 452                poly_step(ch, cl, pkh, pkl, rh, rl);
 453        }
 454
 455do_l3:
 456        vhash_abort(ctx);
 457        remaining *= 8;
 458        return l3hash(ch, cl, ctx->l3key[0], ctx->l3key[1], remaining);
 459}
 460
 461static u64 vmac(unsigned char m[], unsigned int mbytes,
 462                        const unsigned char n[16], u64 *tagl,
 463                        struct vmac_ctx_t *ctx)
 464{
 465        u64 *in_n, *out_p;
 466        u64 p, h;
 467        int i;
 468
 469        in_n = ctx->__vmac_ctx.cached_nonce;
 470        out_p = ctx->__vmac_ctx.cached_aes;
 471
 472        i = n[15] & 1;
 473        if ((*(u64 *)(n+8) != in_n[1]) || (*(u64 *)(n) != in_n[0])) {
 474                in_n[0] = *(u64 *)(n);
 475                in_n[1] = *(u64 *)(n+8);
 476                ((unsigned char *)in_n)[15] &= 0xFE;
 477                crypto_cipher_encrypt_one(ctx->child,
 478                        (unsigned char *)out_p, (unsigned char *)in_n);
 479
 480                ((unsigned char *)in_n)[15] |= (unsigned char)(1-i);
 481        }
 482        p = be64_to_cpup(out_p + i);
 483        h = vhash(m, mbytes, (u64 *)0, &ctx->__vmac_ctx);
 484        return le64_to_cpu(p + h);
 485}
 486
 487static int vmac_set_key(unsigned char user_key[], struct vmac_ctx_t *ctx)
 488{
 489        u64 in[2] = {0}, out[2];
 490        unsigned i;
 491        int err = 0;
 492
 493        err = crypto_cipher_setkey(ctx->child, user_key, VMAC_KEY_LEN);
 494        if (err)
 495                return err;
 496
 497        /* Fill nh key */
 498        ((unsigned char *)in)[0] = 0x80;
 499        for (i = 0; i < sizeof(ctx->__vmac_ctx.nhkey)/8; i += 2) {
 500                crypto_cipher_encrypt_one(ctx->child,
 501                        (unsigned char *)out, (unsigned char *)in);
 502                ctx->__vmac_ctx.nhkey[i] = be64_to_cpup(out);
 503                ctx->__vmac_ctx.nhkey[i+1] = be64_to_cpup(out+1);
 504                ((unsigned char *)in)[15] += 1;
 505        }
 506
 507        /* Fill poly key */
 508        ((unsigned char *)in)[0] = 0xC0;
 509        in[1] = 0;
 510        for (i = 0; i < sizeof(ctx->__vmac_ctx.polykey)/8; i += 2) {
 511                crypto_cipher_encrypt_one(ctx->child,
 512                        (unsigned char *)out, (unsigned char *)in);
 513                ctx->__vmac_ctx.polytmp[i] =
 514                        ctx->__vmac_ctx.polykey[i] =
 515                                be64_to_cpup(out) & mpoly;
 516                ctx->__vmac_ctx.polytmp[i+1] =
 517                        ctx->__vmac_ctx.polykey[i+1] =
 518                                be64_to_cpup(out+1) & mpoly;
 519                ((unsigned char *)in)[15] += 1;
 520        }
 521
 522        /* Fill ip key */
 523        ((unsigned char *)in)[0] = 0xE0;
 524        in[1] = 0;
 525        for (i = 0; i < sizeof(ctx->__vmac_ctx.l3key)/8; i += 2) {
 526                do {
 527                        crypto_cipher_encrypt_one(ctx->child,
 528                                (unsigned char *)out, (unsigned char *)in);
 529                        ctx->__vmac_ctx.l3key[i] = be64_to_cpup(out);
 530                        ctx->__vmac_ctx.l3key[i+1] = be64_to_cpup(out+1);
 531                        ((unsigned char *)in)[15] += 1;
 532                } while (ctx->__vmac_ctx.l3key[i] >= p64
 533                        || ctx->__vmac_ctx.l3key[i+1] >= p64);
 534        }
 535
 536        /* Invalidate nonce/aes cache and reset other elements */
 537        ctx->__vmac_ctx.cached_nonce[0] = (u64)-1; /* Ensure illegal nonce */
 538        ctx->__vmac_ctx.cached_nonce[1] = (u64)0;  /* Ensure illegal nonce */
 539        ctx->__vmac_ctx.first_block_processed = 0;
 540
 541        return err;
 542}
 543
 544static int vmac_setkey(struct crypto_shash *parent,
 545                const u8 *key, unsigned int keylen)
 546{
 547        struct vmac_ctx_t *ctx = crypto_shash_ctx(parent);
 548
 549        if (keylen != VMAC_KEY_LEN) {
 550                crypto_shash_set_flags(parent, CRYPTO_TFM_RES_BAD_KEY_LEN);
 551                return -EINVAL;
 552        }
 553
 554        return vmac_set_key((u8 *)key, ctx);
 555}
 556
 557static int vmac_init(struct shash_desc *pdesc)
 558{
 559        return 0;
 560}
 561
 562static int vmac_update(struct shash_desc *pdesc, const u8 *p,
 563                unsigned int len)
 564{
 565        struct crypto_shash *parent = pdesc->tfm;
 566        struct vmac_ctx_t *ctx = crypto_shash_ctx(parent);
 567        int expand;
 568        int min;
 569
 570        expand = VMAC_NHBYTES - ctx->partial_size > 0 ?
 571                        VMAC_NHBYTES - ctx->partial_size : 0;
 572
 573        min = len < expand ? len : expand;
 574
 575        memcpy(ctx->partial + ctx->partial_size, p, min);
 576        ctx->partial_size += min;
 577
 578        if (len < expand)
 579                return 0;
 580
 581        vhash_update(ctx->partial, VMAC_NHBYTES, &ctx->__vmac_ctx);
 582        ctx->partial_size = 0;
 583
 584        len -= expand;
 585        p += expand;
 586
 587        if (len % VMAC_NHBYTES) {
 588                memcpy(ctx->partial, p + len - (len % VMAC_NHBYTES),
 589                        len % VMAC_NHBYTES);
 590                ctx->partial_size = len % VMAC_NHBYTES;
 591        }
 592
 593        vhash_update(p, len - len % VMAC_NHBYTES, &ctx->__vmac_ctx);
 594
 595        return 0;
 596}
 597
 598static int vmac_final(struct shash_desc *pdesc, u8 *out)
 599{
 600        struct crypto_shash *parent = pdesc->tfm;
 601        struct vmac_ctx_t *ctx = crypto_shash_ctx(parent);
 602        vmac_t mac;
 603        u8 nonce[16] = {};
 604
 605        /* vmac() ends up accessing outside the array bounds that
 606         * we specify.  In appears to access up to the next 2-word
 607         * boundary.  We'll just be uber cautious and zero the
 608         * unwritten bytes in the buffer.
 609         */
 610        if (ctx->partial_size) {
 611                memset(ctx->partial + ctx->partial_size, 0,
 612                        VMAC_NHBYTES - ctx->partial_size);
 613        }
 614        mac = vmac(ctx->partial, ctx->partial_size, nonce, NULL, ctx);
 615        memcpy(out, &mac, sizeof(vmac_t));
 616        memset(&mac, 0, sizeof(vmac_t));
 617        memset(&ctx->__vmac_ctx, 0, sizeof(struct vmac_ctx));
 618        ctx->partial_size = 0;
 619        return 0;
 620}
 621
 622static int vmac_init_tfm(struct crypto_tfm *tfm)
 623{
 624        struct crypto_cipher *cipher;
 625        struct crypto_instance *inst = (void *)tfm->__crt_alg;
 626        struct crypto_spawn *spawn = crypto_instance_ctx(inst);
 627        struct vmac_ctx_t *ctx = crypto_tfm_ctx(tfm);
 628
 629        cipher = crypto_spawn_cipher(spawn);
 630        if (IS_ERR(cipher))
 631                return PTR_ERR(cipher);
 632
 633        ctx->child = cipher;
 634        return 0;
 635}
 636
 637static void vmac_exit_tfm(struct crypto_tfm *tfm)
 638{
 639        struct vmac_ctx_t *ctx = crypto_tfm_ctx(tfm);
 640        crypto_free_cipher(ctx->child);
 641}
 642
 643static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)
 644{
 645        struct shash_instance *inst;
 646        struct crypto_alg *alg;
 647        int err;
 648
 649        err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH);
 650        if (err)
 651                return err;
 652
 653        alg = crypto_get_attr_alg(tb, CRYPTO_ALG_TYPE_CIPHER,
 654                        CRYPTO_ALG_TYPE_MASK);
 655        if (IS_ERR(alg))
 656                return PTR_ERR(alg);
 657
 658        inst = shash_alloc_instance("vmac", alg);
 659        err = PTR_ERR(inst);
 660        if (IS_ERR(inst))
 661                goto out_put_alg;
 662
 663        err = crypto_init_spawn(shash_instance_ctx(inst), alg,
 664                        shash_crypto_instance(inst),
 665                        CRYPTO_ALG_TYPE_MASK);
 666        if (err)
 667                goto out_free_inst;
 668
 669        inst->alg.base.cra_priority = alg->cra_priority;
 670        inst->alg.base.cra_blocksize = alg->cra_blocksize;
 671        inst->alg.base.cra_alignmask = alg->cra_alignmask;
 672
 673        inst->alg.digestsize = sizeof(vmac_t);
 674        inst->alg.base.cra_ctxsize = sizeof(struct vmac_ctx_t);
 675        inst->alg.base.cra_init = vmac_init_tfm;
 676        inst->alg.base.cra_exit = vmac_exit_tfm;
 677
 678        inst->alg.init = vmac_init;
 679        inst->alg.update = vmac_update;
 680        inst->alg.final = vmac_final;
 681        inst->alg.setkey = vmac_setkey;
 682
 683        err = shash_register_instance(tmpl, inst);
 684        if (err) {
 685out_free_inst:
 686                shash_free_instance(shash_crypto_instance(inst));
 687        }
 688
 689out_put_alg:
 690        crypto_mod_put(alg);
 691        return err;
 692}
 693
 694static struct crypto_template vmac_tmpl = {
 695        .name = "vmac",
 696        .create = vmac_create,
 697        .free = shash_free_instance,
 698        .module = THIS_MODULE,
 699};
 700
 701static int __init vmac_module_init(void)
 702{
 703        return crypto_register_template(&vmac_tmpl);
 704}
 705
 706static void __exit vmac_module_exit(void)
 707{
 708        crypto_unregister_template(&vmac_tmpl);
 709}
 710
 711module_init(vmac_module_init);
 712module_exit(vmac_module_exit);
 713
 714MODULE_LICENSE("GPL");
 715MODULE_DESCRIPTION("VMAC hash algorithm");
 716
lxr.linux.no kindly hosted by Redpill Linpro AS, provider of Linux consulting and operations services since 1995.