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1/*2 * VMAC: Message Authentication Code using Universal Hashing3 *4 * Reference: https://tools.ietf.org/html/draft-krovetz-vmac-015 *6 * Copyright (c) 2009, Intel Corporation.7 * Copyright (c) 2018, Google Inc.8 *9 * This program is free software; you can redistribute it and/or modify it10 * under the terms and conditions of the GNU General Public License,11 * version 2, as published by the Free Software Foundation.12 *13 * This program is distributed in the hope it will be useful, but WITHOUT14 * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or15 * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for16 * more details.17 *18 * You should have received a copy of the GNU General Public License along with19 * this program; if not, write to the Free Software Foundation, Inc., 59 Temple20 * Place - Suite 330, Boston, MA 02111-1307 USA.21 */22 23/*24 * Derived from:25 *	VMAC and VHASH Implementation by Ted Krovetz (tdk@acm.org) and Wei Dai.26 *	This implementation is herby placed in the public domain.27 *	The authors offers no warranty. Use at your own risk.28 *	Last modified: 17 APR 08, 1700 PDT29 */30 31#include <linux/unaligned.h>32#include <linux/init.h>33#include <linux/types.h>34#include <linux/crypto.h>35#include <linux/module.h>36#include <linux/scatterlist.h>37#include <asm/byteorder.h>38#include <crypto/scatterwalk.h>39#include <crypto/internal/cipher.h>40#include <crypto/internal/hash.h>41 42/*43 * User definable settings.44 */45#define VMAC_TAG_LEN	6446#define VMAC_KEY_SIZE	128/* Must be 128, 192 or 256			*/47#define VMAC_KEY_LEN	(VMAC_KEY_SIZE/8)48#define VMAC_NHBYTES	128/* Must 2^i for any 3 < i < 13 Standard = 128*/49#define VMAC_NONCEBYTES	1650 51/* per-transform (per-key) context */52struct vmac_tfm_ctx {53	struct crypto_cipher *cipher;54	u64 nhkey[(VMAC_NHBYTES/8)+2*(VMAC_TAG_LEN/64-1)];55	u64 polykey[2*VMAC_TAG_LEN/64];56	u64 l3key[2*VMAC_TAG_LEN/64];57};58 59/* per-request context */60struct vmac_desc_ctx {61	union {62		u8 partial[VMAC_NHBYTES];	/* partial block */63		__le64 partial_words[VMAC_NHBYTES / 8];64	};65	unsigned int partial_size;	/* size of the partial block */66	bool first_block_processed;67	u64 polytmp[2*VMAC_TAG_LEN/64];	/* running total of L2-hash */68	union {69		u8 bytes[VMAC_NONCEBYTES];70		__be64 pads[VMAC_NONCEBYTES / 8];71	} nonce;72	unsigned int nonce_size; /* nonce bytes filled so far */73};74 75/*76 * Constants and masks77 */78#define UINT64_C(x) x##ULL79static const u64 p64   = UINT64_C(0xfffffffffffffeff);	/* 2^64 - 257 prime  */80static const u64 m62   = UINT64_C(0x3fffffffffffffff);	/* 62-bit mask       */81static const u64 m63   = UINT64_C(0x7fffffffffffffff);	/* 63-bit mask       */82static const u64 m64   = UINT64_C(0xffffffffffffffff);	/* 64-bit mask       */83static const u64 mpoly = UINT64_C(0x1fffffff1fffffff);	/* Poly key mask     */84 85#define pe64_to_cpup le64_to_cpup		/* Prefer little endian */86 87#ifdef __LITTLE_ENDIAN88#define INDEX_HIGH 189#define INDEX_LOW 090#else91#define INDEX_HIGH 092#define INDEX_LOW 193#endif94 95/*96 * The following routines are used in this implementation. They are97 * written via macros to simulate zero-overhead call-by-reference.98 *99 * MUL64: 64x64->128-bit multiplication100 * PMUL64: assumes top bits cleared on inputs101 * ADD128: 128x128->128-bit addition102 */103 104#define ADD128(rh, rl, ih, il)						\105	do {								\106		u64 _il = (il);						\107		(rl) += (_il);						\108		if ((rl) < (_il))					\109			(rh)++;						\110		(rh) += (ih);						\111	} while (0)112 113#define MUL32(i1, i2)	((u64)(u32)(i1)*(u32)(i2))114 115#define PMUL64(rh, rl, i1, i2)	/* Assumes m doesn't overflow */	\116	do {								\117		u64 _i1 = (i1), _i2 = (i2);				\118		u64 m = MUL32(_i1, _i2>>32) + MUL32(_i1>>32, _i2);	\119		rh = MUL32(_i1>>32, _i2>>32);				\120		rl = MUL32(_i1, _i2);					\121		ADD128(rh, rl, (m >> 32), (m << 32));			\122	} while (0)123 124#define MUL64(rh, rl, i1, i2)						\125	do {								\126		u64 _i1 = (i1), _i2 = (i2);				\127		u64 m1 = MUL32(_i1, _i2>>32);				\128		u64 m2 = MUL32(_i1>>32, _i2);				\129		rh = MUL32(_i1>>32, _i2>>32);				\130		rl = MUL32(_i1, _i2);					\131		ADD128(rh, rl, (m1 >> 32), (m1 << 32));			\132		ADD128(rh, rl, (m2 >> 32), (m2 << 32));			\133	} while (0)134 135/*136 * For highest performance the L1 NH and L2 polynomial hashes should be137 * carefully implemented to take advantage of one's target architecture.138 * Here these two hash functions are defined multiple time; once for139 * 64-bit architectures, once for 32-bit SSE2 architectures, and once140 * for the rest (32-bit) architectures.141 * For each, nh_16 *must* be defined (works on multiples of 16 bytes).142 * Optionally, nh_vmac_nhbytes can be defined (for multiples of143 * VMAC_NHBYTES), and nh_16_2 and nh_vmac_nhbytes_2 (versions that do two144 * NH computations at once).145 */146 147#ifdef CONFIG_64BIT148 149#define nh_16(mp, kp, nw, rh, rl)					\150	do {								\151		int i; u64 th, tl;					\152		rh = rl = 0;						\153		for (i = 0; i < nw; i += 2) {				\154			MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],	\155				pe64_to_cpup((mp)+i+1)+(kp)[i+1]);	\156			ADD128(rh, rl, th, tl);				\157		}							\158	} while (0)159 160#define nh_16_2(mp, kp, nw, rh, rl, rh1, rl1)				\161	do {								\162		int i; u64 th, tl;					\163		rh1 = rl1 = rh = rl = 0;				\164		for (i = 0; i < nw; i += 2) {				\165			MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],	\166				pe64_to_cpup((mp)+i+1)+(kp)[i+1]);	\167			ADD128(rh, rl, th, tl);				\168			MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i+2],	\169				pe64_to_cpup((mp)+i+1)+(kp)[i+3]);	\170			ADD128(rh1, rl1, th, tl);			\171		}							\172	} while (0)173 174#if (VMAC_NHBYTES >= 64) /* These versions do 64-bytes of message at a time */175#define nh_vmac_nhbytes(mp, kp, nw, rh, rl)				\176	do {								\177		int i; u64 th, tl;					\178		rh = rl = 0;						\179		for (i = 0; i < nw; i += 8) {				\180			MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],	\181				pe64_to_cpup((mp)+i+1)+(kp)[i+1]);	\182			ADD128(rh, rl, th, tl);				\183			MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+2],	\184				pe64_to_cpup((mp)+i+3)+(kp)[i+3]);	\185			ADD128(rh, rl, th, tl);				\186			MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+4],	\187				pe64_to_cpup((mp)+i+5)+(kp)[i+5]);	\188			ADD128(rh, rl, th, tl);				\189			MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+6],	\190				pe64_to_cpup((mp)+i+7)+(kp)[i+7]);	\191			ADD128(rh, rl, th, tl);				\192		}							\193	} while (0)194 195#define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh1, rl1)			\196	do {								\197		int i; u64 th, tl;					\198		rh1 = rl1 = rh = rl = 0;				\199		for (i = 0; i < nw; i += 8) {				\200			MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i],	\201				pe64_to_cpup((mp)+i+1)+(kp)[i+1]);	\202			ADD128(rh, rl, th, tl);				\203			MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i+2],	\204				pe64_to_cpup((mp)+i+1)+(kp)[i+3]);	\205			ADD128(rh1, rl1, th, tl);			\206			MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+2],	\207				pe64_to_cpup((mp)+i+3)+(kp)[i+3]);	\208			ADD128(rh, rl, th, tl);				\209			MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+4],	\210				pe64_to_cpup((mp)+i+3)+(kp)[i+5]);	\211			ADD128(rh1, rl1, th, tl);			\212			MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+4],	\213				pe64_to_cpup((mp)+i+5)+(kp)[i+5]);	\214			ADD128(rh, rl, th, tl);				\215			MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+6],	\216				pe64_to_cpup((mp)+i+5)+(kp)[i+7]);	\217			ADD128(rh1, rl1, th, tl);			\218			MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+6],	\219				pe64_to_cpup((mp)+i+7)+(kp)[i+7]);	\220			ADD128(rh, rl, th, tl);				\221			MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+8],	\222				pe64_to_cpup((mp)+i+7)+(kp)[i+9]);	\223			ADD128(rh1, rl1, th, tl);			\224		}							\225	} while (0)226#endif227 228#define poly_step(ah, al, kh, kl, mh, ml)				\229	do {								\230		u64 t1h, t1l, t2h, t2l, t3h, t3l, z = 0;		\231		/* compute ab*cd, put bd into result registers */	\232		PMUL64(t3h, t3l, al, kh);				\233		PMUL64(t2h, t2l, ah, kl);				\234		PMUL64(t1h, t1l, ah, 2*kh);				\235		PMUL64(ah, al, al, kl);					\236		/* add 2 * ac to result */				\237		ADD128(ah, al, t1h, t1l);				\238		/* add together ad + bc */				\239		ADD128(t2h, t2l, t3h, t3l);				\240		/* now (ah,al), (t2l,2*t2h) need summing */		\241		/* first add the high registers, carrying into t2h */	\242		ADD128(t2h, ah, z, t2l);				\243		/* double t2h and add top bit of ah */			\244		t2h = 2 * t2h + (ah >> 63);				\245		ah &= m63;						\246		/* now add the low registers */				\247		ADD128(ah, al, mh, ml);					\248		ADD128(ah, al, z, t2h);					\249	} while (0)250 251#else /* ! CONFIG_64BIT */252 253#ifndef nh_16254#define nh_16(mp, kp, nw, rh, rl)					\255	do {								\256		u64 t1, t2, m1, m2, t;					\257		int i;							\258		rh = rl = t = 0;					\259		for (i = 0; i < nw; i += 2)  {				\260			t1 = pe64_to_cpup(mp+i) + kp[i];		\261			t2 = pe64_to_cpup(mp+i+1) + kp[i+1];		\262			m2 = MUL32(t1 >> 32, t2);			\263			m1 = MUL32(t1, t2 >> 32);			\264			ADD128(rh, rl, MUL32(t1 >> 32, t2 >> 32),	\265				MUL32(t1, t2));				\266			rh += (u64)(u32)(m1 >> 32)			\267				+ (u32)(m2 >> 32);			\268			t += (u64)(u32)m1 + (u32)m2;			\269		}							\270		ADD128(rh, rl, (t >> 32), (t << 32));			\271	} while (0)272#endif273 274static void poly_step_func(u64 *ahi, u64 *alo,275			const u64 *kh, const u64 *kl,276			const u64 *mh, const u64 *ml)277{278#define a0 (*(((u32 *)alo)+INDEX_LOW))279#define a1 (*(((u32 *)alo)+INDEX_HIGH))280#define a2 (*(((u32 *)ahi)+INDEX_LOW))281#define a3 (*(((u32 *)ahi)+INDEX_HIGH))282#define k0 (*(((u32 *)kl)+INDEX_LOW))283#define k1 (*(((u32 *)kl)+INDEX_HIGH))284#define k2 (*(((u32 *)kh)+INDEX_LOW))285#define k3 (*(((u32 *)kh)+INDEX_HIGH))286 287	u64 p, q, t;288	u32 t2;289 290	p = MUL32(a3, k3);291	p += p;292	p += *(u64 *)mh;293	p += MUL32(a0, k2);294	p += MUL32(a1, k1);295	p += MUL32(a2, k0);296	t = (u32)(p);297	p >>= 32;298	p += MUL32(a0, k3);299	p += MUL32(a1, k2);300	p += MUL32(a2, k1);301	p += MUL32(a3, k0);302	t |= ((u64)((u32)p & 0x7fffffff)) << 32;303	p >>= 31;304	p += (u64)(((u32 *)ml)[INDEX_LOW]);305	p += MUL32(a0, k0);306	q =  MUL32(a1, k3);307	q += MUL32(a2, k2);308	q += MUL32(a3, k1);309	q += q;310	p += q;311	t2 = (u32)(p);312	p >>= 32;313	p += (u64)(((u32 *)ml)[INDEX_HIGH]);314	p += MUL32(a0, k1);315	p += MUL32(a1, k0);316	q =  MUL32(a2, k3);317	q += MUL32(a3, k2);318	q += q;319	p += q;320	*(u64 *)(alo) = (p << 32) | t2;321	p >>= 32;322	*(u64 *)(ahi) = p + t;323 324#undef a0325#undef a1326#undef a2327#undef a3328#undef k0329#undef k1330#undef k2331#undef k3332}333 334#define poly_step(ah, al, kh, kl, mh, ml)				\335	poly_step_func(&(ah), &(al), &(kh), &(kl), &(mh), &(ml))336 337#endif  /* end of specialized NH and poly definitions */338 339/* At least nh_16 is defined. Defined others as needed here */340#ifndef nh_16_2341#define nh_16_2(mp, kp, nw, rh, rl, rh2, rl2)				\342	do { 								\343		nh_16(mp, kp, nw, rh, rl);				\344		nh_16(mp, ((kp)+2), nw, rh2, rl2);			\345	} while (0)346#endif347#ifndef nh_vmac_nhbytes348#define nh_vmac_nhbytes(mp, kp, nw, rh, rl)				\349	nh_16(mp, kp, nw, rh, rl)350#endif351#ifndef nh_vmac_nhbytes_2352#define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh2, rl2)			\353	do {								\354		nh_vmac_nhbytes(mp, kp, nw, rh, rl);			\355		nh_vmac_nhbytes(mp, ((kp)+2), nw, rh2, rl2);		\356	} while (0)357#endif358 359static u64 l3hash(u64 p1, u64 p2, u64 k1, u64 k2, u64 len)360{361	u64 rh, rl, t, z = 0;362 363	/* fully reduce (p1,p2)+(len,0) mod p127 */364	t = p1 >> 63;365	p1 &= m63;366	ADD128(p1, p2, len, t);367	/* At this point, (p1,p2) is at most 2^127+(len<<64) */368	t = (p1 > m63) + ((p1 == m63) && (p2 == m64));369	ADD128(p1, p2, z, t);370	p1 &= m63;371 372	/* compute (p1,p2)/(2^64-2^32) and (p1,p2)%(2^64-2^32) */373	t = p1 + (p2 >> 32);374	t += (t >> 32);375	t += (u32)t > 0xfffffffeu;376	p1 += (t >> 32);377	p2 += (p1 << 32);378 379	/* compute (p1+k1)%p64 and (p2+k2)%p64 */380	p1 += k1;381	p1 += (0 - (p1 < k1)) & 257;382	p2 += k2;383	p2 += (0 - (p2 < k2)) & 257;384 385	/* compute (p1+k1)*(p2+k2)%p64 */386	MUL64(rh, rl, p1, p2);387	t = rh >> 56;388	ADD128(t, rl, z, rh);389	rh <<= 8;390	ADD128(t, rl, z, rh);391	t += t << 8;392	rl += t;393	rl += (0 - (rl < t)) & 257;394	rl += (0 - (rl > p64-1)) & 257;395	return rl;396}397 398/* L1 and L2-hash one or more VMAC_NHBYTES-byte blocks */399static void vhash_blocks(const struct vmac_tfm_ctx *tctx,400			 struct vmac_desc_ctx *dctx,401			 const __le64 *mptr, unsigned int blocks)402{403	const u64 *kptr = tctx->nhkey;404	const u64 pkh = tctx->polykey[0];405	const u64 pkl = tctx->polykey[1];406	u64 ch = dctx->polytmp[0];407	u64 cl = dctx->polytmp[1];408	u64 rh, rl;409 410	if (!dctx->first_block_processed) {411		dctx->first_block_processed = true;412		nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl);413		rh &= m62;414		ADD128(ch, cl, rh, rl);415		mptr += (VMAC_NHBYTES/sizeof(u64));416		blocks--;417	}418 419	while (blocks--) {420		nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl);421		rh &= m62;422		poly_step(ch, cl, pkh, pkl, rh, rl);423		mptr += (VMAC_NHBYTES/sizeof(u64));424	}425 426	dctx->polytmp[0] = ch;427	dctx->polytmp[1] = cl;428}429 430static int vmac_setkey(struct crypto_shash *tfm,431		       const u8 *key, unsigned int keylen)432{433	struct vmac_tfm_ctx *tctx = crypto_shash_ctx(tfm);434	__be64 out[2];435	u8 in[16] = { 0 };436	unsigned int i;437	int err;438 439	if (keylen != VMAC_KEY_LEN)440		return -EINVAL;441 442	err = crypto_cipher_setkey(tctx->cipher, key, keylen);443	if (err)444		return err;445 446	/* Fill nh key */447	in[0] = 0x80;448	for (i = 0; i < ARRAY_SIZE(tctx->nhkey); i += 2) {449		crypto_cipher_encrypt_one(tctx->cipher, (u8 *)out, in);450		tctx->nhkey[i] = be64_to_cpu(out[0]);451		tctx->nhkey[i+1] = be64_to_cpu(out[1]);452		in[15]++;453	}454 455	/* Fill poly key */456	in[0] = 0xC0;457	in[15] = 0;458	for (i = 0; i < ARRAY_SIZE(tctx->polykey); i += 2) {459		crypto_cipher_encrypt_one(tctx->cipher, (u8 *)out, in);460		tctx->polykey[i] = be64_to_cpu(out[0]) & mpoly;461		tctx->polykey[i+1] = be64_to_cpu(out[1]) & mpoly;462		in[15]++;463	}464 465	/* Fill ip key */466	in[0] = 0xE0;467	in[15] = 0;468	for (i = 0; i < ARRAY_SIZE(tctx->l3key); i += 2) {469		do {470			crypto_cipher_encrypt_one(tctx->cipher, (u8 *)out, in);471			tctx->l3key[i] = be64_to_cpu(out[0]);472			tctx->l3key[i+1] = be64_to_cpu(out[1]);473			in[15]++;474		} while (tctx->l3key[i] >= p64 || tctx->l3key[i+1] >= p64);475	}476 477	return 0;478}479 480static int vmac_init(struct shash_desc *desc)481{482	const struct vmac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);483	struct vmac_desc_ctx *dctx = shash_desc_ctx(desc);484 485	dctx->partial_size = 0;486	dctx->first_block_processed = false;487	memcpy(dctx->polytmp, tctx->polykey, sizeof(dctx->polytmp));488	dctx->nonce_size = 0;489	return 0;490}491 492static int vmac_update(struct shash_desc *desc, const u8 *p, unsigned int len)493{494	const struct vmac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);495	struct vmac_desc_ctx *dctx = shash_desc_ctx(desc);496	unsigned int n;497 498	/* Nonce is passed as first VMAC_NONCEBYTES bytes of data */499	if (dctx->nonce_size < VMAC_NONCEBYTES) {500		n = min(len, VMAC_NONCEBYTES - dctx->nonce_size);501		memcpy(&dctx->nonce.bytes[dctx->nonce_size], p, n);502		dctx->nonce_size += n;503		p += n;504		len -= n;505	}506 507	if (dctx->partial_size) {508		n = min(len, VMAC_NHBYTES - dctx->partial_size);509		memcpy(&dctx->partial[dctx->partial_size], p, n);510		dctx->partial_size += n;511		p += n;512		len -= n;513		if (dctx->partial_size == VMAC_NHBYTES) {514			vhash_blocks(tctx, dctx, dctx->partial_words, 1);515			dctx->partial_size = 0;516		}517	}518 519	if (len >= VMAC_NHBYTES) {520		n = round_down(len, VMAC_NHBYTES);521		/* TODO: 'p' may be misaligned here */522		vhash_blocks(tctx, dctx, (const __le64 *)p, n / VMAC_NHBYTES);523		p += n;524		len -= n;525	}526 527	if (len) {528		memcpy(dctx->partial, p, len);529		dctx->partial_size = len;530	}531 532	return 0;533}534 535static u64 vhash_final(const struct vmac_tfm_ctx *tctx,536		       struct vmac_desc_ctx *dctx)537{538	unsigned int partial = dctx->partial_size;539	u64 ch = dctx->polytmp[0];540	u64 cl = dctx->polytmp[1];541 542	/* L1 and L2-hash the final block if needed */543	if (partial) {544		/* Zero-pad to next 128-bit boundary */545		unsigned int n = round_up(partial, 16);546		u64 rh, rl;547 548		memset(&dctx->partial[partial], 0, n - partial);549		nh_16(dctx->partial_words, tctx->nhkey, n / 8, rh, rl);550		rh &= m62;551		if (dctx->first_block_processed)552			poly_step(ch, cl, tctx->polykey[0], tctx->polykey[1],553				  rh, rl);554		else555			ADD128(ch, cl, rh, rl);556	}557 558	/* L3-hash the 128-bit output of L2-hash */559	return l3hash(ch, cl, tctx->l3key[0], tctx->l3key[1], partial * 8);560}561 562static int vmac_final(struct shash_desc *desc, u8 *out)563{564	const struct vmac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);565	struct vmac_desc_ctx *dctx = shash_desc_ctx(desc);566	int index;567	u64 hash, pad;568 569	if (dctx->nonce_size != VMAC_NONCEBYTES)570		return -EINVAL;571 572	/*573	 * The VMAC specification requires a nonce at least 1 bit shorter than574	 * the block cipher's block length, so we actually only accept a 127-bit575	 * nonce.  We define the unused bit to be the first one and require that576	 * it be 0, so the needed prepending of a 0 bit is implicit.577	 */578	if (dctx->nonce.bytes[0] & 0x80)579		return -EINVAL;580 581	/* Finish calculating the VHASH of the message */582	hash = vhash_final(tctx, dctx);583 584	/* Generate pseudorandom pad by encrypting the nonce */585	BUILD_BUG_ON(VMAC_NONCEBYTES != 2 * (VMAC_TAG_LEN / 8));586	index = dctx->nonce.bytes[VMAC_NONCEBYTES - 1] & 1;587	dctx->nonce.bytes[VMAC_NONCEBYTES - 1] &= ~1;588	crypto_cipher_encrypt_one(tctx->cipher, dctx->nonce.bytes,589				  dctx->nonce.bytes);590	pad = be64_to_cpu(dctx->nonce.pads[index]);591 592	/* The VMAC is the sum of VHASH and the pseudorandom pad */593	put_unaligned_be64(hash + pad, out);594	return 0;595}596 597static int vmac_init_tfm(struct crypto_tfm *tfm)598{599	struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);600	struct crypto_cipher_spawn *spawn = crypto_instance_ctx(inst);601	struct vmac_tfm_ctx *tctx = crypto_tfm_ctx(tfm);602	struct crypto_cipher *cipher;603 604	cipher = crypto_spawn_cipher(spawn);605	if (IS_ERR(cipher))606		return PTR_ERR(cipher);607 608	tctx->cipher = cipher;609	return 0;610}611 612static void vmac_exit_tfm(struct crypto_tfm *tfm)613{614	struct vmac_tfm_ctx *tctx = crypto_tfm_ctx(tfm);615 616	crypto_free_cipher(tctx->cipher);617}618 619static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)620{621	struct shash_instance *inst;622	struct crypto_cipher_spawn *spawn;623	struct crypto_alg *alg;624	u32 mask;625	int err;626 627	err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH, &mask);628	if (err)629		return err;630 631	inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);632	if (!inst)633		return -ENOMEM;634	spawn = shash_instance_ctx(inst);635 636	err = crypto_grab_cipher(spawn, shash_crypto_instance(inst),637				 crypto_attr_alg_name(tb[1]), 0, mask);638	if (err)639		goto err_free_inst;640	alg = crypto_spawn_cipher_alg(spawn);641 642	err = -EINVAL;643	if (alg->cra_blocksize != VMAC_NONCEBYTES)644		goto err_free_inst;645 646	err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg);647	if (err)648		goto err_free_inst;649 650	inst->alg.base.cra_priority = alg->cra_priority;651	inst->alg.base.cra_blocksize = alg->cra_blocksize;652 653	inst->alg.base.cra_ctxsize = sizeof(struct vmac_tfm_ctx);654	inst->alg.base.cra_init = vmac_init_tfm;655	inst->alg.base.cra_exit = vmac_exit_tfm;656 657	inst->alg.descsize = sizeof(struct vmac_desc_ctx);658	inst->alg.digestsize = VMAC_TAG_LEN / 8;659	inst->alg.init = vmac_init;660	inst->alg.update = vmac_update;661	inst->alg.final = vmac_final;662	inst->alg.setkey = vmac_setkey;663 664	inst->free = shash_free_singlespawn_instance;665 666	err = shash_register_instance(tmpl, inst);667	if (err) {668err_free_inst:669		shash_free_singlespawn_instance(inst);670	}671	return err;672}673 674static struct crypto_template vmac64_tmpl = {675	.name = "vmac64",676	.create = vmac_create,677	.module = THIS_MODULE,678};679 680static int __init vmac_module_init(void)681{682	return crypto_register_template(&vmac64_tmpl);683}684 685static void __exit vmac_module_exit(void)686{687	crypto_unregister_template(&vmac64_tmpl);688}689 690subsys_initcall(vmac_module_init);691module_exit(vmac_module_exit);692 693MODULE_LICENSE("GPL");694MODULE_DESCRIPTION("VMAC hash algorithm");695MODULE_ALIAS_CRYPTO("vmac64");696MODULE_IMPORT_NS(CRYPTO_INTERNAL);697