1 files changed, 210 insertions, 0 deletions

diff --git a/kernel/arch/powerpc/crypto/sha1-spe-glue.c b/kernel/arch/powerpc/crypto/sha1-spe-glue.c
new file mode 100644
index 000000000..3e1d22212
--- /dev/null
+++ b/kernel/arch/powerpc/crypto/sha1-spe-glue.c
@@ -0,0 +1,210 @@
+/*
+ * Glue code for SHA-1 implementation for SPE instructions (PPC)
+ *
+ * Based on generic implementation.
+ *
+ * Copyright (c) 2015 Markus Stockhausen <stockhausen@collogia.de>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 2 of the License, or (at your option)
+ * any later version.
+ *
+ */
+
+#include <crypto/internal/hash.h>
+#include <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/cryptohash.h>
+#include <linux/types.h>
+#include <crypto/sha.h>
+#include <asm/byteorder.h>
+#include <asm/switch_to.h>
+#include <linux/hardirq.h>
+
+/*
+ * MAX_BYTES defines the number of bytes that are allowed to be processed
+ * between preempt_disable() and preempt_enable(). SHA1 takes ~1000
+ * operations per 64 bytes. e500 cores can issue two arithmetic instructions
+ * per clock cycle using one 32/64 bit unit (SU1) and one 32 bit unit (SU2).
+ * Thus 2KB of input data will need an estimated maximum of 18,000 cycles.
+ * Headroom for cache misses included. Even with the low end model clocked
+ * at 667 MHz this equals to a critical time window of less than 27us.
+ *
+ */
+#define MAX_BYTES 2048
+
+extern void ppc_spe_sha1_transform(u32 *state, const u8 *src, u32 blocks);
+
+static void spe_begin(void)
+{
+	/* We just start SPE operations and will save SPE registers later. */
+	preempt_disable();
+	enable_kernel_spe();
+}
+
+static void spe_end(void)
+{
+	/* reenable preemption */
+	preempt_enable();
+}
+
+static inline void ppc_sha1_clear_context(struct sha1_state *sctx)
+{
+	int count = sizeof(struct sha1_state) >> 2;
+	u32 *ptr = (u32 *)sctx;
+
+	/* make sure we can clear the fast way */
+	BUILD_BUG_ON(sizeof(struct sha1_state) % 4);
+	do { *ptr++ = 0; } while (--count);
+}
+
+static int ppc_spe_sha1_init(struct shash_desc *desc)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+
+	sctx->state[0] = SHA1_H0;
+	sctx->state[1] = SHA1_H1;
+	sctx->state[2] = SHA1_H2;
+	sctx->state[3] = SHA1_H3;
+	sctx->state[4] = SHA1_H4;
+	sctx->count = 0;
+
+	return 0;
+}
+
+static int ppc_spe_sha1_update(struct shash_desc *desc, const u8 *data,
+			unsigned int len)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+	const unsigned int offset = sctx->count & 0x3f;
+	const unsigned int avail = 64 - offset;
+	unsigned int bytes;
+	const u8 *src = data;
+
+	if (avail > len) {
+		sctx->count += len;
+		memcpy((char *)sctx->buffer + offset, src, len);
+		return 0;
+	}
+
+	sctx->count += len;
+
+	if (offset) {
+		memcpy((char *)sctx->buffer + offset, src, avail);
+
+		spe_begin();
+		ppc_spe_sha1_transform(sctx->state, (const u8 *)sctx->buffer, 1);
+		spe_end();
+
+		len -= avail;
+		src += avail;
+	}
+
+	while (len > 63) {
+		bytes = (len > MAX_BYTES) ? MAX_BYTES : len;
+		bytes = bytes & ~0x3f;
+
+		spe_begin();
+		ppc_spe_sha1_transform(sctx->state, src, bytes >> 6);
+		spe_end();
+
+		src += bytes;
+		len -= bytes;
+	};
+
+	memcpy((char *)sctx->buffer, src, len);
+	return 0;
+}
+
+static int ppc_spe_sha1_final(struct shash_desc *desc, u8 *out)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+	const unsigned int offset = sctx->count & 0x3f;
+	char *p = (char *)sctx->buffer + offset;
+	int padlen;
+	__be64 *pbits = (__be64 *)(((char *)&sctx->buffer) + 56);
+	__be32 *dst = (__be32 *)out;
+
+	padlen = 55 - offset;
+	*p++ = 0x80;
+
+	spe_begin();
+
+	if (padlen < 0) {
+		memset(p, 0x00, padlen + sizeof (u64));
+		ppc_spe_sha1_transform(sctx->state, sctx->buffer, 1);
+		p = (char *)sctx->buffer;
+		padlen = 56;
+	}
+
+	memset(p, 0, padlen);
+	*pbits = cpu_to_be64(sctx->count << 3);
+	ppc_spe_sha1_transform(sctx->state, sctx->buffer, 1);
+
+	spe_end();
+
+	dst[0] = cpu_to_be32(sctx->state[0]);
+	dst[1] = cpu_to_be32(sctx->state[1]);
+	dst[2] = cpu_to_be32(sctx->state[2]);
+	dst[3] = cpu_to_be32(sctx->state[3]);
+	dst[4] = cpu_to_be32(sctx->state[4]);
+
+	ppc_sha1_clear_context(sctx);
+	return 0;
+}
+
+static int ppc_spe_sha1_export(struct shash_desc *desc, void *out)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+
+	memcpy(out, sctx, sizeof(*sctx));
+	return 0;
+}
+
+static int ppc_spe_sha1_import(struct shash_desc *desc, const void *in)
+{
+	struct sha1_state *sctx = shash_desc_ctx(desc);
+
+	memcpy(sctx, in, sizeof(*sctx));
+	return 0;
+}
+
+static struct shash_alg alg = {
+	.digestsize	=	SHA1_DIGEST_SIZE,
+	.init		=	ppc_spe_sha1_init,
+	.update		=	ppc_spe_sha1_update,
+	.final		=	ppc_spe_sha1_final,
+	.export		=	ppc_spe_sha1_export,
+	.import		=	ppc_spe_sha1_import,
+	.descsize	=	sizeof(struct sha1_state),
+	.statesize	=	sizeof(struct sha1_state),
+	.base		=	{
+		.cra_name	=	"sha1",
+		.cra_driver_name=	"sha1-ppc-spe",
+		.cra_priority	=	300,
+		.cra_flags	=	CRYPTO_ALG_TYPE_SHASH,
+		.cra_blocksize	=	SHA1_BLOCK_SIZE,
+		.cra_module	=	THIS_MODULE,
+	}
+};
+
+static int __init ppc_spe_sha1_mod_init(void)
+{
+	return crypto_register_shash(&alg);
+}
+
+static void __exit ppc_spe_sha1_mod_fini(void)
+{
+	crypto_unregister_shash(&alg);
+}
+
+module_init(ppc_spe_sha1_mod_init);
+module_exit(ppc_spe_sha1_mod_fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm, SPE optimized");
+
+MODULE_ALIAS_CRYPTO("sha1");
+MODULE_ALIAS_CRYPTO("sha1-ppc-spe");