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-rw-r--r--crypto/sha1_generic.c140
1 files changed, 140 insertions, 0 deletions
diff --git a/crypto/sha1_generic.c b/crypto/sha1_generic.c
new file mode 100644
index 00000000000..48a3c3e0bf5
--- /dev/null
+++ b/crypto/sha1_generic.c
@@ -0,0 +1,140 @@
+/*
+ * Cryptographic API.
+ *
+ * SHA1 Secure Hash Algorithm.
+ *
+ * Derived from cryptoapi implementation, adapted for in-place
+ * scatterlist interface.
+ *
+ * Copyright (c) Alan Smithee.
+ * Copyright (c) Andrew McDonald <andrew@mcdonald.org.uk>
+ * Copyright (c) Jean-Francois Dive <jef@linuxbe.org>
+ *
+ * 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 <linux/init.h>
+#include <linux/module.h>
+#include <linux/mm.h>
+#include <linux/crypto.h>
+#include <linux/cryptohash.h>
+#include <linux/types.h>
+#include <crypto/sha.h>
+#include <asm/scatterlist.h>
+#include <asm/byteorder.h>
+
+struct sha1_ctx {
+ u64 count;
+ u32 state[5];
+ u8 buffer[64];
+};
+
+static void sha1_init(struct crypto_tfm *tfm)
+{
+ struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
+ static const struct sha1_ctx initstate = {
+ 0,
+ { SHA1_H0, SHA1_H1, SHA1_H2, SHA1_H3, SHA1_H4 },
+ { 0, }
+ };
+
+ *sctx = initstate;
+}
+
+static void sha1_update(struct crypto_tfm *tfm, const u8 *data,
+ unsigned int len)
+{
+ struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
+ unsigned int partial, done;
+ const u8 *src;
+
+ partial = sctx->count & 0x3f;
+ sctx->count += len;
+ done = 0;
+ src = data;
+
+ if ((partial + len) > 63) {
+ u32 temp[SHA_WORKSPACE_WORDS];
+
+ if (partial) {
+ done = -partial;
+ memcpy(sctx->buffer + partial, data, done + 64);
+ src = sctx->buffer;
+ }
+
+ do {
+ sha_transform(sctx->state, src, temp);
+ done += 64;
+ src = data + done;
+ } while (done + 63 < len);
+
+ memset(temp, 0, sizeof(temp));
+ partial = 0;
+ }
+ memcpy(sctx->buffer + partial, src, len - done);
+}
+
+
+/* Add padding and return the message digest. */
+static void sha1_final(struct crypto_tfm *tfm, u8 *out)
+{
+ struct sha1_ctx *sctx = crypto_tfm_ctx(tfm);
+ __be32 *dst = (__be32 *)out;
+ u32 i, index, padlen;
+ __be64 bits;
+ static const u8 padding[64] = { 0x80, };
+
+ bits = cpu_to_be64(sctx->count << 3);
+
+ /* Pad out to 56 mod 64 */
+ index = sctx->count & 0x3f;
+ padlen = (index < 56) ? (56 - index) : ((64+56) - index);
+ sha1_update(tfm, padding, padlen);
+
+ /* Append length */
+ sha1_update(tfm, (const u8 *)&bits, sizeof(bits));
+
+ /* Store state in digest */
+ for (i = 0; i < 5; i++)
+ dst[i] = cpu_to_be32(sctx->state[i]);
+
+ /* Wipe context */
+ memset(sctx, 0, sizeof *sctx);
+}
+
+static struct crypto_alg alg = {
+ .cra_name = "sha1",
+ .cra_driver_name= "sha1-generic",
+ .cra_flags = CRYPTO_ALG_TYPE_DIGEST,
+ .cra_blocksize = SHA1_BLOCK_SIZE,
+ .cra_ctxsize = sizeof(struct sha1_ctx),
+ .cra_module = THIS_MODULE,
+ .cra_alignmask = 3,
+ .cra_list = LIST_HEAD_INIT(alg.cra_list),
+ .cra_u = { .digest = {
+ .dia_digestsize = SHA1_DIGEST_SIZE,
+ .dia_init = sha1_init,
+ .dia_update = sha1_update,
+ .dia_final = sha1_final } }
+};
+
+static int __init init(void)
+{
+ return crypto_register_alg(&alg);
+}
+
+static void __exit fini(void)
+{
+ crypto_unregister_alg(&alg);
+}
+
+module_init(init);
+module_exit(fini);
+
+MODULE_LICENSE("GPL");
+MODULE_DESCRIPTION("SHA1 Secure Hash Algorithm");
+
+MODULE_ALIAS("sha1");