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authorArd Biesheuvel <ardb@kernel.org>2019-11-08 13:22:19 +0100
committerHerbert Xu <herbert@gondor.apana.org.au>2019-11-17 09:02:41 +0800
commit48ea8c6ebc96bc0990e12ee1c43d0832c23576bb (patch)
tree2344893a15adb14df257f4375a306353cf0dfdab /crypto/poly1305_generic.c
parent22cf705360707ced15f9fe5423938f313c7df536 (diff)
crypto: poly1305 - move core routines into a separate library
Move the core Poly1305 routines shared between the generic Poly1305 shash driver and the Adiantum and NHPoly1305 drivers into a separate library so that using just this pieces does not pull in the crypto API pieces of the generic Poly1305 routine. In a subsequent patch, we will augment this generic library with init/update/final routines so that Poyl1305 algorithm can be used directly without the need for using the crypto API's shash abstraction. Signed-off-by: Ard Biesheuvel <ardb@kernel.org> Signed-off-by: Herbert Xu <herbert@gondor.apana.org.au>
Diffstat (limited to 'crypto/poly1305_generic.c')
-rw-r--r--crypto/poly1305_generic.c195
1 files changed, 8 insertions, 187 deletions
diff --git a/crypto/poly1305_generic.c b/crypto/poly1305_generic.c
index adc40298c749..067f493c2504 100644
--- a/crypto/poly1305_generic.c
+++ b/crypto/poly1305_generic.c
@@ -13,27 +13,12 @@
#include <crypto/algapi.h>
#include <crypto/internal/hash.h>
-#include <crypto/poly1305.h>
+#include <crypto/internal/poly1305.h>
#include <linux/crypto.h>
#include <linux/kernel.h>
#include <linux/module.h>
#include <asm/unaligned.h>
-static inline u64 mlt(u64 a, u64 b)
-{
- return a * b;
-}
-
-static inline u32 sr(u64 v, u_char n)
-{
- return v >> n;
-}
-
-static inline u32 and(u32 v, u32 mask)
-{
- return v & mask;
-}
-
int crypto_poly1305_init(struct shash_desc *desc)
{
struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
@@ -47,124 +32,8 @@ int crypto_poly1305_init(struct shash_desc *desc)
}
EXPORT_SYMBOL_GPL(crypto_poly1305_init);
-void poly1305_core_setkey(struct poly1305_key *key, const u8 *raw_key)
-{
- /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */
- key->r[0] = (get_unaligned_le32(raw_key + 0) >> 0) & 0x3ffffff;
- key->r[1] = (get_unaligned_le32(raw_key + 3) >> 2) & 0x3ffff03;
- key->r[2] = (get_unaligned_le32(raw_key + 6) >> 4) & 0x3ffc0ff;
- key->r[3] = (get_unaligned_le32(raw_key + 9) >> 6) & 0x3f03fff;
- key->r[4] = (get_unaligned_le32(raw_key + 12) >> 8) & 0x00fffff;
-}
-EXPORT_SYMBOL_GPL(poly1305_core_setkey);
-
-/*
- * Poly1305 requires a unique key for each tag, which implies that we can't set
- * it on the tfm that gets accessed by multiple users simultaneously. Instead we
- * expect the key as the first 32 bytes in the update() call.
- */
-unsigned int crypto_poly1305_setdesckey(struct poly1305_desc_ctx *dctx,
- const u8 *src, unsigned int srclen)
-{
- if (!dctx->sset) {
- if (!dctx->rset && srclen >= POLY1305_BLOCK_SIZE) {
- poly1305_core_setkey(&dctx->r, src);
- src += POLY1305_BLOCK_SIZE;
- srclen -= POLY1305_BLOCK_SIZE;
- dctx->rset = true;
- }
- if (srclen >= POLY1305_BLOCK_SIZE) {
- dctx->s[0] = get_unaligned_le32(src + 0);
- dctx->s[1] = get_unaligned_le32(src + 4);
- dctx->s[2] = get_unaligned_le32(src + 8);
- dctx->s[3] = get_unaligned_le32(src + 12);
- src += POLY1305_BLOCK_SIZE;
- srclen -= POLY1305_BLOCK_SIZE;
- dctx->sset = true;
- }
- }
- return srclen;
-}
-EXPORT_SYMBOL_GPL(crypto_poly1305_setdesckey);
-
-static void poly1305_blocks_internal(struct poly1305_state *state,
- const struct poly1305_key *key,
- const void *src, unsigned int nblocks,
- u32 hibit)
-{
- u32 r0, r1, r2, r3, r4;
- u32 s1, s2, s3, s4;
- u32 h0, h1, h2, h3, h4;
- u64 d0, d1, d2, d3, d4;
-
- if (!nblocks)
- return;
-
- r0 = key->r[0];
- r1 = key->r[1];
- r2 = key->r[2];
- r3 = key->r[3];
- r4 = key->r[4];
-
- s1 = r1 * 5;
- s2 = r2 * 5;
- s3 = r3 * 5;
- s4 = r4 * 5;
-
- h0 = state->h[0];
- h1 = state->h[1];
- h2 = state->h[2];
- h3 = state->h[3];
- h4 = state->h[4];
-
- do {
- /* h += m[i] */
- h0 += (get_unaligned_le32(src + 0) >> 0) & 0x3ffffff;
- h1 += (get_unaligned_le32(src + 3) >> 2) & 0x3ffffff;
- h2 += (get_unaligned_le32(src + 6) >> 4) & 0x3ffffff;
- h3 += (get_unaligned_le32(src + 9) >> 6) & 0x3ffffff;
- h4 += (get_unaligned_le32(src + 12) >> 8) | hibit;
-
- /* h *= r */
- d0 = mlt(h0, r0) + mlt(h1, s4) + mlt(h2, s3) +
- mlt(h3, s2) + mlt(h4, s1);
- d1 = mlt(h0, r1) + mlt(h1, r0) + mlt(h2, s4) +
- mlt(h3, s3) + mlt(h4, s2);
- d2 = mlt(h0, r2) + mlt(h1, r1) + mlt(h2, r0) +
- mlt(h3, s4) + mlt(h4, s3);
- d3 = mlt(h0, r3) + mlt(h1, r2) + mlt(h2, r1) +
- mlt(h3, r0) + mlt(h4, s4);
- d4 = mlt(h0, r4) + mlt(h1, r3) + mlt(h2, r2) +
- mlt(h3, r1) + mlt(h4, r0);
-
- /* (partial) h %= p */
- d1 += sr(d0, 26); h0 = and(d0, 0x3ffffff);
- d2 += sr(d1, 26); h1 = and(d1, 0x3ffffff);
- d3 += sr(d2, 26); h2 = and(d2, 0x3ffffff);
- d4 += sr(d3, 26); h3 = and(d3, 0x3ffffff);
- h0 += sr(d4, 26) * 5; h4 = and(d4, 0x3ffffff);
- h1 += h0 >> 26; h0 = h0 & 0x3ffffff;
-
- src += POLY1305_BLOCK_SIZE;
- } while (--nblocks);
-
- state->h[0] = h0;
- state->h[1] = h1;
- state->h[2] = h2;
- state->h[3] = h3;
- state->h[4] = h4;
-}
-
-void poly1305_core_blocks(struct poly1305_state *state,
- const struct poly1305_key *key,
- const void *src, unsigned int nblocks)
-{
- poly1305_blocks_internal(state, key, src, nblocks, 1 << 24);
-}
-EXPORT_SYMBOL_GPL(poly1305_core_blocks);
-
-static void poly1305_blocks(struct poly1305_desc_ctx *dctx,
- const u8 *src, unsigned int srclen, u32 hibit)
+static void poly1305_blocks(struct poly1305_desc_ctx *dctx, const u8 *src,
+ unsigned int srclen)
{
unsigned int datalen;
@@ -174,8 +43,8 @@ static void poly1305_blocks(struct poly1305_desc_ctx *dctx,
srclen = datalen;
}
- poly1305_blocks_internal(&dctx->h, &dctx->r,
- src, srclen / POLY1305_BLOCK_SIZE, hibit);
+ poly1305_core_blocks(&dctx->h, &dctx->r, src,
+ srclen / POLY1305_BLOCK_SIZE, 1);
}
int crypto_poly1305_update(struct shash_desc *desc,
@@ -193,13 +62,13 @@ int crypto_poly1305_update(struct shash_desc *desc,
if (dctx->buflen == POLY1305_BLOCK_SIZE) {
poly1305_blocks(dctx, dctx->buf,
- POLY1305_BLOCK_SIZE, 1 << 24);
+ POLY1305_BLOCK_SIZE);
dctx->buflen = 0;
}
}
if (likely(srclen >= POLY1305_BLOCK_SIZE)) {
- poly1305_blocks(dctx, src, srclen, 1 << 24);
+ poly1305_blocks(dctx, src, srclen);
src += srclen - (srclen % POLY1305_BLOCK_SIZE);
srclen %= POLY1305_BLOCK_SIZE;
}
@@ -213,54 +82,6 @@ int crypto_poly1305_update(struct shash_desc *desc,
}
EXPORT_SYMBOL_GPL(crypto_poly1305_update);
-void poly1305_core_emit(const struct poly1305_state *state, void *dst)
-{
- u32 h0, h1, h2, h3, h4;
- u32 g0, g1, g2, g3, g4;
- u32 mask;
-
- /* fully carry h */
- h0 = state->h[0];
- h1 = state->h[1];
- h2 = state->h[2];
- h3 = state->h[3];
- h4 = state->h[4];
-
- h2 += (h1 >> 26); h1 = h1 & 0x3ffffff;
- h3 += (h2 >> 26); h2 = h2 & 0x3ffffff;
- h4 += (h3 >> 26); h3 = h3 & 0x3ffffff;
- h0 += (h4 >> 26) * 5; h4 = h4 & 0x3ffffff;
- h1 += (h0 >> 26); h0 = h0 & 0x3ffffff;
-
- /* compute h + -p */
- g0 = h0 + 5;
- g1 = h1 + (g0 >> 26); g0 &= 0x3ffffff;
- g2 = h2 + (g1 >> 26); g1 &= 0x3ffffff;
- g3 = h3 + (g2 >> 26); g2 &= 0x3ffffff;
- g4 = h4 + (g3 >> 26) - (1 << 26); g3 &= 0x3ffffff;
-
- /* select h if h < p, or h + -p if h >= p */
- mask = (g4 >> ((sizeof(u32) * 8) - 1)) - 1;
- g0 &= mask;
- g1 &= mask;
- g2 &= mask;
- g3 &= mask;
- g4 &= mask;
- mask = ~mask;
- h0 = (h0 & mask) | g0;
- h1 = (h1 & mask) | g1;
- h2 = (h2 & mask) | g2;
- h3 = (h3 & mask) | g3;
- h4 = (h4 & mask) | g4;
-
- /* h = h % (2^128) */
- put_unaligned_le32((h0 >> 0) | (h1 << 26), dst + 0);
- put_unaligned_le32((h1 >> 6) | (h2 << 20), dst + 4);
- put_unaligned_le32((h2 >> 12) | (h3 << 14), dst + 8);
- put_unaligned_le32((h3 >> 18) | (h4 << 8), dst + 12);
-}
-EXPORT_SYMBOL_GPL(poly1305_core_emit);
-
int crypto_poly1305_final(struct shash_desc *desc, u8 *dst)
{
struct poly1305_desc_ctx *dctx = shash_desc_ctx(desc);
@@ -274,7 +95,7 @@ int crypto_poly1305_final(struct shash_desc *desc, u8 *dst)
dctx->buf[dctx->buflen++] = 1;
memset(dctx->buf + dctx->buflen, 0,
POLY1305_BLOCK_SIZE - dctx->buflen);
- poly1305_blocks(dctx, dctx->buf, POLY1305_BLOCK_SIZE, 0);
+ poly1305_core_blocks(&dctx->h, &dctx->r, dctx->buf, 1, 0);
}
poly1305_core_emit(&dctx->h, digest);