[S390] dasd: fix race between tasklet and dasd_sleep_on
[sfrench/cifs-2.6.git] / crypto / vmac.c
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