To reduce the number of copies of boilerplate code throughout
the tree, this patch implements generic glue for the SHA-1
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>
---
include/crypto/sha1_base.h | 123 +++++++++++++++++++++++++++++++++++++++++++++
1 file changed, 123 insertions(+)
create mode 100644 include/crypto/sha1_base.h
diff --git a/include/crypto/sha1_base.h b/include/crypto/sha1_base.h
new file mode 100644
index 000000000000..919db0920203
--- /dev/null
+++ b/include/crypto/sha1_base.h
@@ -0,0 +1,123 @@
+/*
+ * sha1_base.h - core logic for SHA-1 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>
+
+typedef void (sha1_block_fn)(int blocks, u8 const *src, u32 *state,
+ const u8 *head, void *p);
+
+static inline int sha1_base_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 inline int sha1_base_export(struct shash_desc *desc, void *out)
+{
+ struct sha1_state *sctx = shash_desc_ctx(desc);
+ struct sha1_state *dst = out;
+
+ *dst = *sctx;
+
+ return 0;
+}
+
+static inline int sha1_base_import(struct shash_desc *desc, const void *in)
+{
+ struct sha1_state *sctx = shash_desc_ctx(desc);
+ struct sha1_state const *src = in;
+
+ *sctx = *src;
+
+ return 0;
+}
+
+static inline int sha1_base_do_update(struct shash_desc *desc, const u8 *data,
+ unsigned int len, sha1_block_fn *block_fn,
+ void *p)
+{
+ struct sha1_state *sctx = shash_desc_ctx(desc);
+ unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
+
+ sctx->count += len;
+
+ if (unlikely((partial + len) >= SHA1_BLOCK_SIZE)) {
+ int blocks;
+
+ if (partial) {
+ int p = SHA1_BLOCK_SIZE - partial;
+
+ memcpy(sctx->buffer + partial, data, p);
+ data += p;
+ len -= p;
+ }
+
+ blocks = len / SHA1_BLOCK_SIZE;
+ len %= SHA1_BLOCK_SIZE;
+
+ block_fn(blocks, data, sctx->state,
+ partial ? sctx->buffer : NULL, p);
+ data += blocks * SHA1_BLOCK_SIZE;
+ partial = 0;
+ }
+ if (len)
+ memcpy(sctx->buffer + partial, data, len);
+
+ return 0;
+}
+
+static inline int sha1_base_do_finalize(struct shash_desc *desc,
+ sha1_block_fn *block_fn, void *p)
+{
+ const int bit_offset = SHA1_BLOCK_SIZE - sizeof(__be64);
+ struct sha1_state *sctx = shash_desc_ctx(desc);
+ __be64 *bits = (__be64 *)(sctx->buffer + bit_offset);
+ unsigned int partial = sctx->count % SHA1_BLOCK_SIZE;
+
+ sctx->buffer[partial++] = 0x80;
+ if (partial > bit_offset) {
+ memset(sctx->buffer + partial, 0x0, SHA1_BLOCK_SIZE - partial);
+ partial = 0;
+
+ block_fn(1, sctx->buffer, sctx->state, NULL, p);
+ }
+
+ memset(sctx->buffer + partial, 0x0, bit_offset - partial);
+ *bits = cpu_to_be64(sctx->count << 3);
+ block_fn(1, sctx->buffer, sctx->state, NULL, p);
+
+ return 0;
+}
+
+static inline int sha1_base_finish(struct shash_desc *desc, u8 *out)
+{
+ struct sha1_state *sctx = shash_desc_ctx(desc);
+ __be32 *digest = (__be32 *)out;
+ int i;
+
+ for (i = 0; i < SHA1_DIGEST_SIZE / sizeof(__be32); i++)
+ put_unaligned_be32(sctx->state[i], digest++);
+
+ *sctx = (struct sha1_state){};
+ return 0;
+}
--
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
