To reduce the number of copies of boilerplate code throughout
the tree, this patch implements generic glue for the SHA-256
algorithm. This allows a specific arch or hardware implementation
to only implement the special handling that it needs.
Signed-off-by: Ard Biesheuvel <ard.biesheuvel@xxxxxxxxxx>
---
crypto/Kconfig | 4 ++
crypto/Makefile | 1 +
crypto/sha256_base.c | 138 +++++++++++++++++++++++++++++++++++++++++++++++++++
include/crypto/sha.h | 17 +++++++
4 files changed, 160 insertions(+)
create mode 100644 crypto/sha256_base.c
diff --git a/crypto/Kconfig b/crypto/Kconfig
index 880aa518c2eb..551bbf2e2ab5 100644
--- a/crypto/Kconfig
+++ b/crypto/Kconfig
@@ -602,6 +602,10 @@ config CRYPTO_SHA1_MB
lanes remain unfilled, a flush operation will be initiated to
process the crypto jobs, adding a slight latency.
+
+config CRYPTO_SHA256_BASE
+ tristate
+
config CRYPTO_SHA256
tristate "SHA224 and SHA256 digest algorithm"
select CRYPTO_HASH
diff --git a/crypto/Makefile b/crypto/Makefile
index 6174bf2592fe..bb9bafeb3ac7 100644
--- a/crypto/Makefile
+++ b/crypto/Makefile
@@ -44,6 +44,7 @@ obj-$(CONFIG_CRYPTO_RMD160) += rmd160.o
obj-$(CONFIG_CRYPTO_RMD256) += rmd256.o
obj-$(CONFIG_CRYPTO_RMD320) += rmd320.o
obj-$(CONFIG_CRYPTO_SHA1) += sha1_generic.o
+obj-$(CONFIG_CRYPTO_SHA256_BASE) += sha256_base.o
obj-$(CONFIG_CRYPTO_SHA256) += sha256_generic.o
obj-$(CONFIG_CRYPTO_SHA512_BASE) += sha512_base.o
obj-$(CONFIG_CRYPTO_SHA512) += sha512_generic.o
diff --git a/crypto/sha256_base.c b/crypto/sha256_base.c
new file mode 100644
index 000000000000..1ba2f6812c6b
--- /dev/null
+++ b/crypto/sha256_base.c
@@ -0,0 +1,138 @@
+/*
+ * sha256_base.c - core logic for SHA-256 implementations
+ *
+ * Copyright (C) 2015 Linaro Ltd <ard.biesheuvel@xxxxxxxxxx>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License version 2 as
+ * published by the Free Software Foundation.
+ */
+
+#include <crypto/internal/hash.h>
+#include <crypto/sha.h>
+#include <linux/crypto.h>
+#include <linux/module.h>
+
+#include <asm/unaligned.h>
+
+int sha224_base_init(struct shash_desc *desc)
+{
+ struct sha256_state *sctx = shash_desc_ctx(desc);
+
+ *sctx = (struct sha256_state){
+ .state = {
+ SHA224_H0, SHA224_H1, SHA224_H2, SHA224_H3,
+ SHA224_H4, SHA224_H5, SHA224_H6, SHA224_H7,
+ }
+ };
+ return 0;
+}
+EXPORT_SYMBOL(sha224_base_init);
+
+int sha256_base_init(struct shash_desc *desc)
+{
+ struct sha256_state *sctx = shash_desc_ctx(desc);
+
+ *sctx = (struct sha256_state){
+ .state = {
+ SHA256_H0, SHA256_H1, SHA256_H2, SHA256_H3,
+ SHA256_H4, SHA256_H5, SHA256_H6, SHA256_H7,
+ }
+ };
+ return 0;
+}
+EXPORT_SYMBOL(sha256_base_init);
+
+int sha256_base_export(struct shash_desc *desc, void *out)
+{
+ struct sha256_state *sctx = shash_desc_ctx(desc);
+ struct sha256_state *dst = out;
+
+ *dst = *sctx;
+
+ return 0;
+}
+EXPORT_SYMBOL(sha256_base_export);
+
+int sha256_base_import(struct shash_desc *desc, const void *in)
+{
+ struct sha256_state *sctx = shash_desc_ctx(desc);
+ struct sha256_state const *src = in;
+
+ *sctx = *src;
+
+ return 0;
+}
+EXPORT_SYMBOL(sha256_base_import);
+
+int sha256_base_do_update(struct shash_desc *desc, const u8 *data,
+ unsigned int len, sha256_block_fn *block_fn, void *p)
+{
+ struct sha256_state *sctx = shash_desc_ctx(desc);
+ unsigned int partial = sctx->count % SHA256_BLOCK_SIZE;
+
+ sctx->count += len;
+
+ if ((partial + len) >= SHA256_BLOCK_SIZE) {
+ int blocks;
+
+ if (partial) {
+ int p = SHA256_BLOCK_SIZE - partial;
+
+ memcpy(sctx->buf + partial, data, p);
+ data += p;
+ len -= p;
+ }
+
+ blocks = len / SHA256_BLOCK_SIZE;
+ len %= SHA256_BLOCK_SIZE;
+
+ block_fn(blocks, data, sctx->state,
+ partial ? sctx->buf : NULL, p);
+ data += blocks * SHA256_BLOCK_SIZE;
+ partial = 0;
+ }
+ if (len)
+ memcpy(sctx->buf + partial, data, len);
+
+ return 0;
+}
+EXPORT_SYMBOL(sha256_base_do_update);
+
+int sha256_base_do_finalize(struct shash_desc *desc, sha256_block_fn *block_fn,
+ void *p)
+{
+ static const u8 padding[SHA256_BLOCK_SIZE] = { 0x80, };
+
+ struct sha256_state *sctx = shash_desc_ctx(desc);
+ unsigned int padlen;
+ __be64 bits;
+
+ padlen = SHA256_BLOCK_SIZE -
+ (sctx->count + sizeof(bits)) % SHA256_BLOCK_SIZE;
+
+ bits = cpu_to_be64(sctx->count << 3);
+
+ sha256_base_do_update(desc, padding, padlen, block_fn, p);
+
+ memcpy(sctx->buf + SHA256_BLOCK_SIZE - sizeof(bits),
+ &bits, sizeof(bits));
+ block_fn(1, sctx->buf, sctx->state, NULL, p);
+ return 0;
+}
+EXPORT_SYMBOL(sha256_base_do_finalize);
+
+int sha256_base_finish(struct shash_desc *desc, u8 *out)
+{
+ unsigned int digest_size = crypto_shash_digestsize(desc->tfm);
+ struct sha256_state *sctx = shash_desc_ctx(desc);
+ __be32 *digest = (__be32 *)out;
+ int i;
+
+ for (i = 0; digest_size > 0; i++, digest_size -= sizeof(__be32))
+ put_unaligned_be32(sctx->state[i], digest++);
+
+ *sctx = (struct sha256_state){};
+ return 0;
+}
+EXPORT_SYMBOL(sha256_base_finish);
diff --git a/include/crypto/sha.h b/include/crypto/sha.h
index d252a8fcc4de..bc87995e9771 100644
--- a/include/crypto/sha.h
+++ b/include/crypto/sha.h
@@ -82,6 +82,8 @@ struct sha512_state {
u8 buf[SHA512_BLOCK_SIZE];
};
+typedef void (sha256_block_fn)(int blocks, u8 const *src, u32 *state,
+ const u8 *head, void *p);
typedef void (sha512_block_fn)(int blocks, u8 const *src, u64 *state,
const u8 *head, void *p);
@@ -112,4 +114,19 @@ extern int sha512_base_do_finalize(struct shash_desc *desc,
extern int sha512_base_finish(struct shash_desc *desc, u8 *out);
+extern int sha224_base_init(struct shash_desc *desc);
+extern int sha256_base_init(struct shash_desc *desc);
+
+extern int sha256_base_export(struct shash_desc *desc, void *out);
+extern int sha256_base_import(struct shash_desc *desc, const void *in);
+
+extern int sha256_base_do_update(struct shash_desc *desc, const u8 *data,
+ unsigned int len, sha256_block_fn *block_fn,
+ void *p);
+
+extern int sha256_base_do_finalize(struct shash_desc *desc,
+ sha256_block_fn *block_fn, void *p);
+
+extern int sha256_base_finish(struct shash_desc *desc, u8 *out);
+
#endif
--
1.8.3.2
--
To unsubscribe from this list: send the line "unsubscribe linux-crypto" in
the body of a message to majordomo@xxxxxxxxxxxxxxx
More majordomo info at http://vger.kernel.org/majordomo-info.html
