1 files changed, 78 insertions, 0 deletions
diff --git a/lib/crypto/poly1305.c b/lib/crypto/poly1305.c
new file mode 100644
index 000000000000..26d87fc3823e
--- /dev/null
+++ b/lib/crypto/poly1305.c
@@ -0,0 +1,78 @@
+// SPDX-License-Identifier: GPL-2.0-or-later
+/*
+ * Poly1305 authenticator algorithm, RFC7539
+ *
+ * Copyright (C) 2015 Martin Willi
+ *
+ * Based on public domain code by Andrew Moon and Daniel J. Bernstein.
+ */
+
+#include <crypto/internal/poly1305.h>
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <asm/unaligned.h>
+
+void poly1305_init_generic(struct poly1305_desc_ctx *desc,
+			   const u8 key[POLY1305_KEY_SIZE])
+{
+	poly1305_core_setkey(&desc->core_r, key);
+	desc->s[0] = get_unaligned_le32(key + 16);
+	desc->s[1] = get_unaligned_le32(key + 20);
+	desc->s[2] = get_unaligned_le32(key + 24);
+	desc->s[3] = get_unaligned_le32(key + 28);
+	poly1305_core_init(&desc->h);
+	desc->buflen = 0;
+	desc->sset = true;
+	desc->rset = 2;
+}
+EXPORT_SYMBOL_GPL(poly1305_init_generic);
+
+void poly1305_update_generic(struct poly1305_desc_ctx *desc, const u8 *src,
+			     unsigned int nbytes)
+{
+	unsigned int bytes;
+
+	if (unlikely(desc->buflen)) {
+		bytes = min(nbytes, POLY1305_BLOCK_SIZE - desc->buflen);
+		memcpy(desc->buf + desc->buflen, src, bytes);
+		src += bytes;
+		nbytes -= bytes;
+		desc->buflen += bytes;
+
+		if (desc->buflen == POLY1305_BLOCK_SIZE) {
+			poly1305_core_blocks(&desc->h, &desc->core_r, desc->buf,
+					     1, 1);
+			desc->buflen = 0;
+		}
+	}
+
+	if (likely(nbytes >= POLY1305_BLOCK_SIZE)) {
+		poly1305_core_blocks(&desc->h, &desc->core_r, src,
+				     nbytes / POLY1305_BLOCK_SIZE, 1);
+		src += nbytes - (nbytes % POLY1305_BLOCK_SIZE);
+		nbytes %= POLY1305_BLOCK_SIZE;
+	}
+
+	if (unlikely(nbytes)) {
+		desc->buflen = nbytes;
+		memcpy(desc->buf, src, nbytes);
+	}
+}
+EXPORT_SYMBOL_GPL(poly1305_update_generic);
+
+void poly1305_final_generic(struct poly1305_desc_ctx *desc, u8 *dst)
+{
+	if (unlikely(desc->buflen)) {
+		desc->buf[desc->buflen++] = 1;
+		memset(desc->buf + desc->buflen, 0,
+		       POLY1305_BLOCK_SIZE - desc->buflen);
+		poly1305_core_blocks(&desc->h, &desc->core_r, desc->buf, 1, 0);
+	}
+
+	poly1305_core_emit(&desc->h, desc->s, dst);
+	*desc = (struct poly1305_desc_ctx){};
+}
+EXPORT_SYMBOL_GPL(poly1305_final_generic);
+
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Martin Willi <martin@strongswan.org>");