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-rw-r--r--lib/crypto/poly1305-donna32.c204
1 files changed, 204 insertions, 0 deletions
diff --git a/lib/crypto/poly1305-donna32.c b/lib/crypto/poly1305-donna32.c
new file mode 100644
index 000000000000..3cc77d94390b
--- /dev/null
+++ b/lib/crypto/poly1305-donna32.c
@@ -0,0 +1,204 @@
+// SPDX-License-Identifier: GPL-2.0 OR MIT
+/*
+ * Copyright (C) 2015-2019 Jason A. Donenfeld <Jason@zx2c4.com>. All Rights Reserved.
+ *
+ * This is based in part on Andrew Moon's poly1305-donna, which is in the
+ * public domain.
+ */
+
+#include <linux/kernel.h>
+#include <asm/unaligned.h>
+#include <crypto/internal/poly1305.h>
+
+void poly1305_core_setkey(struct poly1305_core_key *key, const u8 raw_key[16])
+{
+ /* r &= 0xffffffc0ffffffc0ffffffc0fffffff */
+ key->key.r[0] = (get_unaligned_le32(&raw_key[0])) & 0x3ffffff;
+ key->key.r[1] = (get_unaligned_le32(&raw_key[3]) >> 2) & 0x3ffff03;
+ key->key.r[2] = (get_unaligned_le32(&raw_key[6]) >> 4) & 0x3ffc0ff;
+ key->key.r[3] = (get_unaligned_le32(&raw_key[9]) >> 6) & 0x3f03fff;
+ key->key.r[4] = (get_unaligned_le32(&raw_key[12]) >> 8) & 0x00fffff;
+
+ /* s = 5*r */
+ key->precomputed_s.r[0] = key->key.r[1] * 5;
+ key->precomputed_s.r[1] = key->key.r[2] * 5;
+ key->precomputed_s.r[2] = key->key.r[3] * 5;
+ key->precomputed_s.r[3] = key->key.r[4] * 5;
+}
+EXPORT_SYMBOL(poly1305_core_setkey);
+
+void poly1305_core_blocks(struct poly1305_state *state,
+ const struct poly1305_core_key *key, const void *src,
+ unsigned int nblocks, u32 hibit)
+{
+ const u8 *input = src;
+ u32 r0, r1, r2, r3, r4;
+ u32 s1, s2, s3, s4;
+ u32 h0, h1, h2, h3, h4;
+ u64 d0, d1, d2, d3, d4;
+ u32 c;
+
+ if (!nblocks)
+ return;
+
+ hibit <<= 24;
+
+ r0 = key->key.r[0];
+ r1 = key->key.r[1];
+ r2 = key->key.r[2];
+ r3 = key->key.r[3];
+ r4 = key->key.r[4];
+
+ s1 = key->precomputed_s.r[0];
+ s2 = key->precomputed_s.r[1];
+ s3 = key->precomputed_s.r[2];
+ s4 = key->precomputed_s.r[3];
+
+ 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(&input[0])) & 0x3ffffff;
+ h1 += (get_unaligned_le32(&input[3]) >> 2) & 0x3ffffff;
+ h2 += (get_unaligned_le32(&input[6]) >> 4) & 0x3ffffff;
+ h3 += (get_unaligned_le32(&input[9]) >> 6) & 0x3ffffff;
+ h4 += (get_unaligned_le32(&input[12]) >> 8) | hibit;
+
+ /* h *= r */
+ d0 = ((u64)h0 * r0) + ((u64)h1 * s4) +
+ ((u64)h2 * s3) + ((u64)h3 * s2) +
+ ((u64)h4 * s1);
+ d1 = ((u64)h0 * r1) + ((u64)h1 * r0) +
+ ((u64)h2 * s4) + ((u64)h3 * s3) +
+ ((u64)h4 * s2);
+ d2 = ((u64)h0 * r2) + ((u64)h1 * r1) +
+ ((u64)h2 * r0) + ((u64)h3 * s4) +
+ ((u64)h4 * s3);
+ d3 = ((u64)h0 * r3) + ((u64)h1 * r2) +
+ ((u64)h2 * r1) + ((u64)h3 * r0) +
+ ((u64)h4 * s4);
+ d4 = ((u64)h0 * r4) + ((u64)h1 * r3) +
+ ((u64)h2 * r2) + ((u64)h3 * r1) +
+ ((u64)h4 * r0);
+
+ /* (partial) h %= p */
+ c = (u32)(d0 >> 26);
+ h0 = (u32)d0 & 0x3ffffff;
+ d1 += c;
+ c = (u32)(d1 >> 26);
+ h1 = (u32)d1 & 0x3ffffff;
+ d2 += c;
+ c = (u32)(d2 >> 26);
+ h2 = (u32)d2 & 0x3ffffff;
+ d3 += c;
+ c = (u32)(d3 >> 26);
+ h3 = (u32)d3 & 0x3ffffff;
+ d4 += c;
+ c = (u32)(d4 >> 26);
+ h4 = (u32)d4 & 0x3ffffff;
+ h0 += c * 5;
+ c = (h0 >> 26);
+ h0 = h0 & 0x3ffffff;
+ h1 += c;
+
+ input += 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;
+}
+EXPORT_SYMBOL(poly1305_core_blocks);
+
+void poly1305_core_emit(const struct poly1305_state *state, const u32 nonce[4],
+ void *dst)
+{
+ u8 *mac = dst;
+ u32 h0, h1, h2, h3, h4, c;
+ u32 g0, g1, g2, g3, g4;
+ u64 f;
+ 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];
+
+ c = h1 >> 26;
+ h1 = h1 & 0x3ffffff;
+ h2 += c;
+ c = h2 >> 26;
+ h2 = h2 & 0x3ffffff;
+ h3 += c;
+ c = h3 >> 26;
+ h3 = h3 & 0x3ffffff;
+ h4 += c;
+ c = h4 >> 26;
+ h4 = h4 & 0x3ffffff;
+ h0 += c * 5;
+ c = h0 >> 26;
+ h0 = h0 & 0x3ffffff;
+ h1 += c;
+
+ /* compute h + -p */
+ g0 = h0 + 5;
+ c = g0 >> 26;
+ g0 &= 0x3ffffff;
+ g1 = h1 + c;
+ c = g1 >> 26;
+ g1 &= 0x3ffffff;
+ g2 = h2 + c;
+ c = g2 >> 26;
+ g2 &= 0x3ffffff;
+ g3 = h3 + c;
+ c = g3 >> 26;
+ g3 &= 0x3ffffff;
+ g4 = h4 + c - (1UL << 26);
+
+ /* 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) */
+ h0 = ((h0) | (h1 << 26)) & 0xffffffff;
+ h1 = ((h1 >> 6) | (h2 << 20)) & 0xffffffff;
+ h2 = ((h2 >> 12) | (h3 << 14)) & 0xffffffff;
+ h3 = ((h3 >> 18) | (h4 << 8)) & 0xffffffff;
+
+ if (likely(nonce)) {
+ /* mac = (h + nonce) % (2^128) */
+ f = (u64)h0 + nonce[0];
+ h0 = (u32)f;
+ f = (u64)h1 + nonce[1] + (f >> 32);
+ h1 = (u32)f;
+ f = (u64)h2 + nonce[2] + (f >> 32);
+ h2 = (u32)f;
+ f = (u64)h3 + nonce[3] + (f >> 32);
+ h3 = (u32)f;
+ }
+
+ put_unaligned_le32(h0, &mac[0]);
+ put_unaligned_le32(h1, &mac[4]);
+ put_unaligned_le32(h2, &mac[8]);
+ put_unaligned_le32(h3, &mac[12]);
+}
+EXPORT_SYMBOL(poly1305_core_emit);