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-rw-r--r--include/crypto/internal/poly1305.h58
1 files changed, 58 insertions, 0 deletions
diff --git a/include/crypto/internal/poly1305.h b/include/crypto/internal/poly1305.h
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+++ b/include/crypto/internal/poly1305.h
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+/* SPDX-License-Identifier: GPL-2.0 */
+/*
+ * Common values for the Poly1305 algorithm
+ */
+
+#ifndef _CRYPTO_INTERNAL_POLY1305_H
+#define _CRYPTO_INTERNAL_POLY1305_H
+
+#include <asm/unaligned.h>
+#include <linux/types.h>
+#include <crypto/poly1305.h>
+
+/*
+ * Poly1305 core functions. These implement the ε-almost-∆-universal hash
+ * function underlying the Poly1305 MAC, i.e. they don't add an encrypted nonce
+ * ("s key") at the end. They also only support block-aligned inputs.
+ */
+void poly1305_core_setkey(struct poly1305_key *key, const u8 *raw_key);
+static inline void poly1305_core_init(struct poly1305_state *state)
+{
+ *state = (struct poly1305_state){};
+}
+
+void poly1305_core_blocks(struct poly1305_state *state,
+ const struct poly1305_key *key, const void *src,
+ unsigned int nblocks, u32 hibit);
+void poly1305_core_emit(const struct poly1305_state *state, void *dst);
+
+/*
+ * 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.
+ */
+static inline
+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 = 1;
+ }
+ 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;
+}
+
+#endif