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-rw-r--r--crypto/vmac.c697
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diff --git a/crypto/vmac.c b/crypto/vmac.c
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+++ b/crypto/vmac.c
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+/*
+ * VMAC: Message Authentication Code using Universal Hashing
+ *
+ * Reference: https://tools.ietf.org/html/draft-krovetz-vmac-01
+ *
+ * Copyright (c) 2009, Intel Corporation.
+ * Copyright (c) 2018, Google Inc.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc., 59 Temple
+ * Place - Suite 330, Boston, MA 02111-1307 USA.
+ */
+
+/*
+ * Derived from:
+ * VMAC and VHASH Implementation by Ted Krovetz (tdk@acm.org) and Wei Dai.
+ * This implementation is herby placed in the public domain.
+ * The authors offers no warranty. Use at your own risk.
+ * Last modified: 17 APR 08, 1700 PDT
+ */
+
+#include <asm/unaligned.h>
+#include <linux/init.h>
+#include <linux/types.h>
+#include <linux/crypto.h>
+#include <linux/module.h>
+#include <linux/scatterlist.h>
+#include <asm/byteorder.h>
+#include <crypto/scatterwalk.h>
+#include <crypto/internal/cipher.h>
+#include <crypto/internal/hash.h>
+
+/*
+ * User definable settings.
+ */
+#define VMAC_TAG_LEN 64
+#define VMAC_KEY_SIZE 128/* Must be 128, 192 or 256 */
+#define VMAC_KEY_LEN (VMAC_KEY_SIZE/8)
+#define VMAC_NHBYTES 128/* Must 2^i for any 3 < i < 13 Standard = 128*/
+#define VMAC_NONCEBYTES 16
+
+/* per-transform (per-key) context */
+struct vmac_tfm_ctx {
+ struct crypto_cipher *cipher;
+ u64 nhkey[(VMAC_NHBYTES/8)+2*(VMAC_TAG_LEN/64-1)];
+ u64 polykey[2*VMAC_TAG_LEN/64];
+ u64 l3key[2*VMAC_TAG_LEN/64];
+};
+
+/* per-request context */
+struct vmac_desc_ctx {
+ union {
+ u8 partial[VMAC_NHBYTES]; /* partial block */
+ __le64 partial_words[VMAC_NHBYTES / 8];
+ };
+ unsigned int partial_size; /* size of the partial block */
+ bool first_block_processed;
+ u64 polytmp[2*VMAC_TAG_LEN/64]; /* running total of L2-hash */
+ union {
+ u8 bytes[VMAC_NONCEBYTES];
+ __be64 pads[VMAC_NONCEBYTES / 8];
+ } nonce;
+ unsigned int nonce_size; /* nonce bytes filled so far */
+};
+
+/*
+ * Constants and masks
+ */
+#define UINT64_C(x) x##ULL
+static const u64 p64 = UINT64_C(0xfffffffffffffeff); /* 2^64 - 257 prime */
+static const u64 m62 = UINT64_C(0x3fffffffffffffff); /* 62-bit mask */
+static const u64 m63 = UINT64_C(0x7fffffffffffffff); /* 63-bit mask */
+static const u64 m64 = UINT64_C(0xffffffffffffffff); /* 64-bit mask */
+static const u64 mpoly = UINT64_C(0x1fffffff1fffffff); /* Poly key mask */
+
+#define pe64_to_cpup le64_to_cpup /* Prefer little endian */
+
+#ifdef __LITTLE_ENDIAN
+#define INDEX_HIGH 1
+#define INDEX_LOW 0
+#else
+#define INDEX_HIGH 0
+#define INDEX_LOW 1
+#endif
+
+/*
+ * The following routines are used in this implementation. They are
+ * written via macros to simulate zero-overhead call-by-reference.
+ *
+ * MUL64: 64x64->128-bit multiplication
+ * PMUL64: assumes top bits cleared on inputs
+ * ADD128: 128x128->128-bit addition
+ */
+
+#define ADD128(rh, rl, ih, il) \
+ do { \
+ u64 _il = (il); \
+ (rl) += (_il); \
+ if ((rl) < (_il)) \
+ (rh)++; \
+ (rh) += (ih); \
+ } while (0)
+
+#define MUL32(i1, i2) ((u64)(u32)(i1)*(u32)(i2))
+
+#define PMUL64(rh, rl, i1, i2) /* Assumes m doesn't overflow */ \
+ do { \
+ u64 _i1 = (i1), _i2 = (i2); \
+ u64 m = MUL32(_i1, _i2>>32) + MUL32(_i1>>32, _i2); \
+ rh = MUL32(_i1>>32, _i2>>32); \
+ rl = MUL32(_i1, _i2); \
+ ADD128(rh, rl, (m >> 32), (m << 32)); \
+ } while (0)
+
+#define MUL64(rh, rl, i1, i2) \
+ do { \
+ u64 _i1 = (i1), _i2 = (i2); \
+ u64 m1 = MUL32(_i1, _i2>>32); \
+ u64 m2 = MUL32(_i1>>32, _i2); \
+ rh = MUL32(_i1>>32, _i2>>32); \
+ rl = MUL32(_i1, _i2); \
+ ADD128(rh, rl, (m1 >> 32), (m1 << 32)); \
+ ADD128(rh, rl, (m2 >> 32), (m2 << 32)); \
+ } while (0)
+
+/*
+ * For highest performance the L1 NH and L2 polynomial hashes should be
+ * carefully implemented to take advantage of one's target architecture.
+ * Here these two hash functions are defined multiple time; once for
+ * 64-bit architectures, once for 32-bit SSE2 architectures, and once
+ * for the rest (32-bit) architectures.
+ * For each, nh_16 *must* be defined (works on multiples of 16 bytes).
+ * Optionally, nh_vmac_nhbytes can be defined (for multiples of
+ * VMAC_NHBYTES), and nh_16_2 and nh_vmac_nhbytes_2 (versions that do two
+ * NH computations at once).
+ */
+
+#ifdef CONFIG_64BIT
+
+#define nh_16(mp, kp, nw, rh, rl) \
+ do { \
+ int i; u64 th, tl; \
+ rh = rl = 0; \
+ for (i = 0; i < nw; i += 2) { \
+ MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i], \
+ pe64_to_cpup((mp)+i+1)+(kp)[i+1]); \
+ ADD128(rh, rl, th, tl); \
+ } \
+ } while (0)
+
+#define nh_16_2(mp, kp, nw, rh, rl, rh1, rl1) \
+ do { \
+ int i; u64 th, tl; \
+ rh1 = rl1 = rh = rl = 0; \
+ for (i = 0; i < nw; i += 2) { \
+ MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i], \
+ pe64_to_cpup((mp)+i+1)+(kp)[i+1]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i+2], \
+ pe64_to_cpup((mp)+i+1)+(kp)[i+3]); \
+ ADD128(rh1, rl1, th, tl); \
+ } \
+ } while (0)
+
+#if (VMAC_NHBYTES >= 64) /* These versions do 64-bytes of message at a time */
+#define nh_vmac_nhbytes(mp, kp, nw, rh, rl) \
+ do { \
+ int i; u64 th, tl; \
+ rh = rl = 0; \
+ for (i = 0; i < nw; i += 8) { \
+ MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i], \
+ pe64_to_cpup((mp)+i+1)+(kp)[i+1]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+2], \
+ pe64_to_cpup((mp)+i+3)+(kp)[i+3]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+4], \
+ pe64_to_cpup((mp)+i+5)+(kp)[i+5]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+6], \
+ pe64_to_cpup((mp)+i+7)+(kp)[i+7]); \
+ ADD128(rh, rl, th, tl); \
+ } \
+ } while (0)
+
+#define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh1, rl1) \
+ do { \
+ int i; u64 th, tl; \
+ rh1 = rl1 = rh = rl = 0; \
+ for (i = 0; i < nw; i += 8) { \
+ MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i], \
+ pe64_to_cpup((mp)+i+1)+(kp)[i+1]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i)+(kp)[i+2], \
+ pe64_to_cpup((mp)+i+1)+(kp)[i+3]); \
+ ADD128(rh1, rl1, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+2], \
+ pe64_to_cpup((mp)+i+3)+(kp)[i+3]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+2)+(kp)[i+4], \
+ pe64_to_cpup((mp)+i+3)+(kp)[i+5]); \
+ ADD128(rh1, rl1, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+4], \
+ pe64_to_cpup((mp)+i+5)+(kp)[i+5]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+4)+(kp)[i+6], \
+ pe64_to_cpup((mp)+i+5)+(kp)[i+7]); \
+ ADD128(rh1, rl1, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+6], \
+ pe64_to_cpup((mp)+i+7)+(kp)[i+7]); \
+ ADD128(rh, rl, th, tl); \
+ MUL64(th, tl, pe64_to_cpup((mp)+i+6)+(kp)[i+8], \
+ pe64_to_cpup((mp)+i+7)+(kp)[i+9]); \
+ ADD128(rh1, rl1, th, tl); \
+ } \
+ } while (0)
+#endif
+
+#define poly_step(ah, al, kh, kl, mh, ml) \
+ do { \
+ u64 t1h, t1l, t2h, t2l, t3h, t3l, z = 0; \
+ /* compute ab*cd, put bd into result registers */ \
+ PMUL64(t3h, t3l, al, kh); \
+ PMUL64(t2h, t2l, ah, kl); \
+ PMUL64(t1h, t1l, ah, 2*kh); \
+ PMUL64(ah, al, al, kl); \
+ /* add 2 * ac to result */ \
+ ADD128(ah, al, t1h, t1l); \
+ /* add together ad + bc */ \
+ ADD128(t2h, t2l, t3h, t3l); \
+ /* now (ah,al), (t2l,2*t2h) need summing */ \
+ /* first add the high registers, carrying into t2h */ \
+ ADD128(t2h, ah, z, t2l); \
+ /* double t2h and add top bit of ah */ \
+ t2h = 2 * t2h + (ah >> 63); \
+ ah &= m63; \
+ /* now add the low registers */ \
+ ADD128(ah, al, mh, ml); \
+ ADD128(ah, al, z, t2h); \
+ } while (0)
+
+#else /* ! CONFIG_64BIT */
+
+#ifndef nh_16
+#define nh_16(mp, kp, nw, rh, rl) \
+ do { \
+ u64 t1, t2, m1, m2, t; \
+ int i; \
+ rh = rl = t = 0; \
+ for (i = 0; i < nw; i += 2) { \
+ t1 = pe64_to_cpup(mp+i) + kp[i]; \
+ t2 = pe64_to_cpup(mp+i+1) + kp[i+1]; \
+ m2 = MUL32(t1 >> 32, t2); \
+ m1 = MUL32(t1, t2 >> 32); \
+ ADD128(rh, rl, MUL32(t1 >> 32, t2 >> 32), \
+ MUL32(t1, t2)); \
+ rh += (u64)(u32)(m1 >> 32) \
+ + (u32)(m2 >> 32); \
+ t += (u64)(u32)m1 + (u32)m2; \
+ } \
+ ADD128(rh, rl, (t >> 32), (t << 32)); \
+ } while (0)
+#endif
+
+static void poly_step_func(u64 *ahi, u64 *alo,
+ const u64 *kh, const u64 *kl,
+ const u64 *mh, const u64 *ml)
+{
+#define a0 (*(((u32 *)alo)+INDEX_LOW))
+#define a1 (*(((u32 *)alo)+INDEX_HIGH))
+#define a2 (*(((u32 *)ahi)+INDEX_LOW))
+#define a3 (*(((u32 *)ahi)+INDEX_HIGH))
+#define k0 (*(((u32 *)kl)+INDEX_LOW))
+#define k1 (*(((u32 *)kl)+INDEX_HIGH))
+#define k2 (*(((u32 *)kh)+INDEX_LOW))
+#define k3 (*(((u32 *)kh)+INDEX_HIGH))
+
+ u64 p, q, t;
+ u32 t2;
+
+ p = MUL32(a3, k3);
+ p += p;
+ p += *(u64 *)mh;
+ p += MUL32(a0, k2);
+ p += MUL32(a1, k1);
+ p += MUL32(a2, k0);
+ t = (u32)(p);
+ p >>= 32;
+ p += MUL32(a0, k3);
+ p += MUL32(a1, k2);
+ p += MUL32(a2, k1);
+ p += MUL32(a3, k0);
+ t |= ((u64)((u32)p & 0x7fffffff)) << 32;
+ p >>= 31;
+ p += (u64)(((u32 *)ml)[INDEX_LOW]);
+ p += MUL32(a0, k0);
+ q = MUL32(a1, k3);
+ q += MUL32(a2, k2);
+ q += MUL32(a3, k1);
+ q += q;
+ p += q;
+ t2 = (u32)(p);
+ p >>= 32;
+ p += (u64)(((u32 *)ml)[INDEX_HIGH]);
+ p += MUL32(a0, k1);
+ p += MUL32(a1, k0);
+ q = MUL32(a2, k3);
+ q += MUL32(a3, k2);
+ q += q;
+ p += q;
+ *(u64 *)(alo) = (p << 32) | t2;
+ p >>= 32;
+ *(u64 *)(ahi) = p + t;
+
+#undef a0
+#undef a1
+#undef a2
+#undef a3
+#undef k0
+#undef k1
+#undef k2
+#undef k3
+}
+
+#define poly_step(ah, al, kh, kl, mh, ml) \
+ poly_step_func(&(ah), &(al), &(kh), &(kl), &(mh), &(ml))
+
+#endif /* end of specialized NH and poly definitions */
+
+/* At least nh_16 is defined. Defined others as needed here */
+#ifndef nh_16_2
+#define nh_16_2(mp, kp, nw, rh, rl, rh2, rl2) \
+ do { \
+ nh_16(mp, kp, nw, rh, rl); \
+ nh_16(mp, ((kp)+2), nw, rh2, rl2); \
+ } while (0)
+#endif
+#ifndef nh_vmac_nhbytes
+#define nh_vmac_nhbytes(mp, kp, nw, rh, rl) \
+ nh_16(mp, kp, nw, rh, rl)
+#endif
+#ifndef nh_vmac_nhbytes_2
+#define nh_vmac_nhbytes_2(mp, kp, nw, rh, rl, rh2, rl2) \
+ do { \
+ nh_vmac_nhbytes(mp, kp, nw, rh, rl); \
+ nh_vmac_nhbytes(mp, ((kp)+2), nw, rh2, rl2); \
+ } while (0)
+#endif
+
+static u64 l3hash(u64 p1, u64 p2, u64 k1, u64 k2, u64 len)
+{
+ u64 rh, rl, t, z = 0;
+
+ /* fully reduce (p1,p2)+(len,0) mod p127 */
+ t = p1 >> 63;
+ p1 &= m63;
+ ADD128(p1, p2, len, t);
+ /* At this point, (p1,p2) is at most 2^127+(len<<64) */
+ t = (p1 > m63) + ((p1 == m63) && (p2 == m64));
+ ADD128(p1, p2, z, t);
+ p1 &= m63;
+
+ /* compute (p1,p2)/(2^64-2^32) and (p1,p2)%(2^64-2^32) */
+ t = p1 + (p2 >> 32);
+ t += (t >> 32);
+ t += (u32)t > 0xfffffffeu;
+ p1 += (t >> 32);
+ p2 += (p1 << 32);
+
+ /* compute (p1+k1)%p64 and (p2+k2)%p64 */
+ p1 += k1;
+ p1 += (0 - (p1 < k1)) & 257;
+ p2 += k2;
+ p2 += (0 - (p2 < k2)) & 257;
+
+ /* compute (p1+k1)*(p2+k2)%p64 */
+ MUL64(rh, rl, p1, p2);
+ t = rh >> 56;
+ ADD128(t, rl, z, rh);
+ rh <<= 8;
+ ADD128(t, rl, z, rh);
+ t += t << 8;
+ rl += t;
+ rl += (0 - (rl < t)) & 257;
+ rl += (0 - (rl > p64-1)) & 257;
+ return rl;
+}
+
+/* L1 and L2-hash one or more VMAC_NHBYTES-byte blocks */
+static void vhash_blocks(const struct vmac_tfm_ctx *tctx,
+ struct vmac_desc_ctx *dctx,
+ const __le64 *mptr, unsigned int blocks)
+{
+ const u64 *kptr = tctx->nhkey;
+ const u64 pkh = tctx->polykey[0];
+ const u64 pkl = tctx->polykey[1];
+ u64 ch = dctx->polytmp[0];
+ u64 cl = dctx->polytmp[1];
+ u64 rh, rl;
+
+ if (!dctx->first_block_processed) {
+ dctx->first_block_processed = true;
+ nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl);
+ rh &= m62;
+ ADD128(ch, cl, rh, rl);
+ mptr += (VMAC_NHBYTES/sizeof(u64));
+ blocks--;
+ }
+
+ while (blocks--) {
+ nh_vmac_nhbytes(mptr, kptr, VMAC_NHBYTES/8, rh, rl);
+ rh &= m62;
+ poly_step(ch, cl, pkh, pkl, rh, rl);
+ mptr += (VMAC_NHBYTES/sizeof(u64));
+ }
+
+ dctx->polytmp[0] = ch;
+ dctx->polytmp[1] = cl;
+}
+
+static int vmac_setkey(struct crypto_shash *tfm,
+ const u8 *key, unsigned int keylen)
+{
+ struct vmac_tfm_ctx *tctx = crypto_shash_ctx(tfm);
+ __be64 out[2];
+ u8 in[16] = { 0 };
+ unsigned int i;
+ int err;
+
+ if (keylen != VMAC_KEY_LEN)
+ return -EINVAL;
+
+ err = crypto_cipher_setkey(tctx->cipher, key, keylen);
+ if (err)
+ return err;
+
+ /* Fill nh key */
+ in[0] = 0x80;
+ for (i = 0; i < ARRAY_SIZE(tctx->nhkey); i += 2) {
+ crypto_cipher_encrypt_one(tctx->cipher, (u8 *)out, in);
+ tctx->nhkey[i] = be64_to_cpu(out[0]);
+ tctx->nhkey[i+1] = be64_to_cpu(out[1]);
+ in[15]++;
+ }
+
+ /* Fill poly key */
+ in[0] = 0xC0;
+ in[15] = 0;
+ for (i = 0; i < ARRAY_SIZE(tctx->polykey); i += 2) {
+ crypto_cipher_encrypt_one(tctx->cipher, (u8 *)out, in);
+ tctx->polykey[i] = be64_to_cpu(out[0]) & mpoly;
+ tctx->polykey[i+1] = be64_to_cpu(out[1]) & mpoly;
+ in[15]++;
+ }
+
+ /* Fill ip key */
+ in[0] = 0xE0;
+ in[15] = 0;
+ for (i = 0; i < ARRAY_SIZE(tctx->l3key); i += 2) {
+ do {
+ crypto_cipher_encrypt_one(tctx->cipher, (u8 *)out, in);
+ tctx->l3key[i] = be64_to_cpu(out[0]);
+ tctx->l3key[i+1] = be64_to_cpu(out[1]);
+ in[15]++;
+ } while (tctx->l3key[i] >= p64 || tctx->l3key[i+1] >= p64);
+ }
+
+ return 0;
+}
+
+static int vmac_init(struct shash_desc *desc)
+{
+ const struct vmac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
+ struct vmac_desc_ctx *dctx = shash_desc_ctx(desc);
+
+ dctx->partial_size = 0;
+ dctx->first_block_processed = false;
+ memcpy(dctx->polytmp, tctx->polykey, sizeof(dctx->polytmp));
+ dctx->nonce_size = 0;
+ return 0;
+}
+
+static int vmac_update(struct shash_desc *desc, const u8 *p, unsigned int len)
+{
+ const struct vmac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
+ struct vmac_desc_ctx *dctx = shash_desc_ctx(desc);
+ unsigned int n;
+
+ /* Nonce is passed as first VMAC_NONCEBYTES bytes of data */
+ if (dctx->nonce_size < VMAC_NONCEBYTES) {
+ n = min(len, VMAC_NONCEBYTES - dctx->nonce_size);
+ memcpy(&dctx->nonce.bytes[dctx->nonce_size], p, n);
+ dctx->nonce_size += n;
+ p += n;
+ len -= n;
+ }
+
+ if (dctx->partial_size) {
+ n = min(len, VMAC_NHBYTES - dctx->partial_size);
+ memcpy(&dctx->partial[dctx->partial_size], p, n);
+ dctx->partial_size += n;
+ p += n;
+ len -= n;
+ if (dctx->partial_size == VMAC_NHBYTES) {
+ vhash_blocks(tctx, dctx, dctx->partial_words, 1);
+ dctx->partial_size = 0;
+ }
+ }
+
+ if (len >= VMAC_NHBYTES) {
+ n = round_down(len, VMAC_NHBYTES);
+ /* TODO: 'p' may be misaligned here */
+ vhash_blocks(tctx, dctx, (const __le64 *)p, n / VMAC_NHBYTES);
+ p += n;
+ len -= n;
+ }
+
+ if (len) {
+ memcpy(dctx->partial, p, len);
+ dctx->partial_size = len;
+ }
+
+ return 0;
+}
+
+static u64 vhash_final(const struct vmac_tfm_ctx *tctx,
+ struct vmac_desc_ctx *dctx)
+{
+ unsigned int partial = dctx->partial_size;
+ u64 ch = dctx->polytmp[0];
+ u64 cl = dctx->polytmp[1];
+
+ /* L1 and L2-hash the final block if needed */
+ if (partial) {
+ /* Zero-pad to next 128-bit boundary */
+ unsigned int n = round_up(partial, 16);
+ u64 rh, rl;
+
+ memset(&dctx->partial[partial], 0, n - partial);
+ nh_16(dctx->partial_words, tctx->nhkey, n / 8, rh, rl);
+ rh &= m62;
+ if (dctx->first_block_processed)
+ poly_step(ch, cl, tctx->polykey[0], tctx->polykey[1],
+ rh, rl);
+ else
+ ADD128(ch, cl, rh, rl);
+ }
+
+ /* L3-hash the 128-bit output of L2-hash */
+ return l3hash(ch, cl, tctx->l3key[0], tctx->l3key[1], partial * 8);
+}
+
+static int vmac_final(struct shash_desc *desc, u8 *out)
+{
+ const struct vmac_tfm_ctx *tctx = crypto_shash_ctx(desc->tfm);
+ struct vmac_desc_ctx *dctx = shash_desc_ctx(desc);
+ int index;
+ u64 hash, pad;
+
+ if (dctx->nonce_size != VMAC_NONCEBYTES)
+ return -EINVAL;
+
+ /*
+ * The VMAC specification requires a nonce at least 1 bit shorter than
+ * the block cipher's block length, so we actually only accept a 127-bit
+ * nonce. We define the unused bit to be the first one and require that
+ * it be 0, so the needed prepending of a 0 bit is implicit.
+ */
+ if (dctx->nonce.bytes[0] & 0x80)
+ return -EINVAL;
+
+ /* Finish calculating the VHASH of the message */
+ hash = vhash_final(tctx, dctx);
+
+ /* Generate pseudorandom pad by encrypting the nonce */
+ BUILD_BUG_ON(VMAC_NONCEBYTES != 2 * (VMAC_TAG_LEN / 8));
+ index = dctx->nonce.bytes[VMAC_NONCEBYTES - 1] & 1;
+ dctx->nonce.bytes[VMAC_NONCEBYTES - 1] &= ~1;
+ crypto_cipher_encrypt_one(tctx->cipher, dctx->nonce.bytes,
+ dctx->nonce.bytes);
+ pad = be64_to_cpu(dctx->nonce.pads[index]);
+
+ /* The VMAC is the sum of VHASH and the pseudorandom pad */
+ put_unaligned_be64(hash + pad, out);
+ return 0;
+}
+
+static int vmac_init_tfm(struct crypto_tfm *tfm)
+{
+ struct crypto_instance *inst = crypto_tfm_alg_instance(tfm);
+ struct crypto_cipher_spawn *spawn = crypto_instance_ctx(inst);
+ struct vmac_tfm_ctx *tctx = crypto_tfm_ctx(tfm);
+ struct crypto_cipher *cipher;
+
+ cipher = crypto_spawn_cipher(spawn);
+ if (IS_ERR(cipher))
+ return PTR_ERR(cipher);
+
+ tctx->cipher = cipher;
+ return 0;
+}
+
+static void vmac_exit_tfm(struct crypto_tfm *tfm)
+{
+ struct vmac_tfm_ctx *tctx = crypto_tfm_ctx(tfm);
+
+ crypto_free_cipher(tctx->cipher);
+}
+
+static int vmac_create(struct crypto_template *tmpl, struct rtattr **tb)
+{
+ struct shash_instance *inst;
+ struct crypto_cipher_spawn *spawn;
+ struct crypto_alg *alg;
+ u32 mask;
+ int err;
+
+ err = crypto_check_attr_type(tb, CRYPTO_ALG_TYPE_SHASH, &mask);
+ if (err)
+ return err;
+
+ inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL);
+ if (!inst)
+ return -ENOMEM;
+ spawn = shash_instance_ctx(inst);
+
+ err = crypto_grab_cipher(spawn, shash_crypto_instance(inst),
+ crypto_attr_alg_name(tb[1]), 0, mask);
+ if (err)
+ goto err_free_inst;
+ alg = crypto_spawn_cipher_alg(spawn);
+
+ err = -EINVAL;
+ if (alg->cra_blocksize != VMAC_NONCEBYTES)
+ goto err_free_inst;
+
+ err = crypto_inst_setname(shash_crypto_instance(inst), tmpl->name, alg);
+ if (err)
+ goto err_free_inst;
+
+ inst->alg.base.cra_priority = alg->cra_priority;
+ inst->alg.base.cra_blocksize = alg->cra_blocksize;
+ inst->alg.base.cra_alignmask = alg->cra_alignmask;
+
+ inst->alg.base.cra_ctxsize = sizeof(struct vmac_tfm_ctx);
+ inst->alg.base.cra_init = vmac_init_tfm;
+ inst->alg.base.cra_exit = vmac_exit_tfm;
+
+ inst->alg.descsize = sizeof(struct vmac_desc_ctx);
+ inst->alg.digestsize = VMAC_TAG_LEN / 8;
+ inst->alg.init = vmac_init;
+ inst->alg.update = vmac_update;
+ inst->alg.final = vmac_final;
+ inst->alg.setkey = vmac_setkey;
+
+ inst->free = shash_free_singlespawn_instance;
+
+ err = shash_register_instance(tmpl, inst);
+ if (err) {
+err_free_inst:
+ shash_free_singlespawn_instance(inst);
+ }
+ return err;
+}
+
+static struct crypto_template vmac64_tmpl = {
+ .name = "vmac64",
+ .create = vmac_create,
+ .module = THIS_MODULE,
+};
+
+static int __init vmac_module_init(void)
+{
+ return crypto_register_template(&vmac64_tmpl);
+}
+
+static void __exit vmac_module_exit(void)
+{
+ crypto_unregister_template(&vmac64_tmpl);
+}
+
+subsys_initcall(vmac_module_init);
+module_exit(vmac_module_exit);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("VMAC hash algorithm");
+MODULE_ALIAS_CRYPTO("vmac64");
+MODULE_IMPORT_NS(CRYPTO_INTERNAL);
generated by cgit v1.2.3 (git 2.39.1) at 2024-11-04 11:30:39 +0000