1 files changed, 96 insertions, 0 deletions

diff --git a/lib/sha1.c b/lib/sha1.c
new file mode 100644
index 000000000000..2f7f1148dfde
--- /dev/null
+++ b/lib/sha1.c
@@ -0,0 +1,96 @@
+/*
+ * SHA transform algorithm, originally taken from code written by
+ * Peter Gutmann, and placed in the public domain.
+ */
+
+#include <linux/kernel.h>
+#include <linux/module.h>
+#include <linux/cryptohash.h>
+
+/* The SHA f()-functions.  */
+
+#define f1(x,y,z)   (z ^ (x & (y ^ z)))         /* x ? y : z */
+#define f2(x,y,z)   (x ^ y ^ z)                 /* XOR */
+#define f3(x,y,z)   ((x & y) + (z & (x ^ y)))   /* majority */
+
+/* The SHA Mysterious Constants */
+
+#define K1  0x5A827999L                 /* Rounds  0-19: sqrt(2) * 2^30 */
+#define K2  0x6ED9EBA1L                 /* Rounds 20-39: sqrt(3) * 2^30 */
+#define K3  0x8F1BBCDCL                 /* Rounds 40-59: sqrt(5) * 2^30 */
+#define K4  0xCA62C1D6L                 /* Rounds 60-79: sqrt(10) * 2^30 */
+
+/*
+ * sha_transform: single block SHA1 transform
+ *
+ * @digest: 160 bit digest to update
+ * @data:   512 bits of data to hash
+ * @W:      80 words of workspace (see note)
+ *
+ * This function generates a SHA1 digest for a single 512-bit block.
+ * Be warned, it does not handle padding and message digest, do not
+ * confuse it with the full FIPS 180-1 digest algorithm for variable
+ * length messages.
+ *
+ * Note: If the hash is security sensitive, the caller should be sure
+ * to clear the workspace. This is left to the caller to avoid
+ * unnecessary clears between chained hashing operations.
+ */
+void sha_transform(__u32 *digest, const char *in, __u32 *W)
+{
+        __u32 a, b, c, d, e, t, i;
+
+        for (i = 0; i < 16; i++)
+                W[i] = be32_to_cpu(((const __u32 *)in)[i]);
+
+        for (i = 0; i < 64; i++)
+                W[i+16] = rol32(W[i+13] ^ W[i+8] ^ W[i+2] ^ W[i], 1);
+
+        a = digest[0];
+        b = digest[1];
+        c = digest[2];
+        d = digest[3];
+        e = digest[4];
+
+        for (i = 0; i < 20; i++) {
+                t = f1(b, c, d) + K1 + rol32(a, 5) + e + W[i];
+                e = d; d = c; c = rol32(b, 30); b = a; a = t;
+        }
+
+        for (; i < 40; i ++) {
+                t = f2(b, c, d) + K2 + rol32(a, 5) + e + W[i];
+                e = d; d = c; c = rol32(b, 30); b = a; a = t;
+        }
+
+        for (; i < 60; i ++) {
+                t = f3(b, c, d) + K3 + rol32(a, 5) + e + W[i];
+                e = d; d = c; c = rol32(b, 30); b = a; a = t;
+        }
+
+        for (; i < 80; i ++) {
+                t = f2(b, c, d) + K4 + rol32(a, 5) + e + W[i];
+                e = d; d = c; c = rol32(b, 30); b = a; a = t;
+        }
+
+        digest[0] += a;
+        digest[1] += b;
+        digest[2] += c;
+        digest[3] += d;
+        digest[4] += e;
+}
+EXPORT_SYMBOL(sha_transform);
+
+/*
+ * sha_init: initialize the vectors for a SHA1 digest
+ *
+ * @buf: vector to initialize
+ */
+void sha_init(__u32 *buf)
+{
+        buf[0] = 0x67452301;
+        buf[1] = 0xefcdab89;
+        buf[2] = 0x98badcfe;
+        buf[3] = 0x10325476;
+        buf[4] = 0xc3d2e1f0;
+}
+