1 files changed, 53 insertions, 0 deletions
diff --git a/src/libstdcrypto/sha256_transform.c b/src/libstdcrypto/sha256_transform.c
new file mode 100644
index 0000000..e61775c
--- /dev/null
+++ b/src/libstdcrypto/sha256_transform.c
@@ -0,0 +1,53 @@
+/* ISC license. */
+
+#include <skalibs/uint32.h>
+#include "sha256-internal.h"
+
+#define F1(x, y, z) ((x & y) | ((~x) & z))
+#define F2(x, y, z) ((x & y) | (x & z) | (y & z))
+
+#define ROTR(x,n) (((x)>>(n)) | ((x)<<(32-(n))))
+#define CAPITALSIGMA0(x) (ROTR(x,2)^ROTR(x,13)^ROTR(x,22))
+#define CAPITALSIGMA1(x) (ROTR(x,6)^ROTR(x,11)^ROTR(x,25))
+#define SMALLSIGMA0(x) (ROTR(x,7)^ROTR(x,18)^((x)>>3))
+#define SMALLSIGMA1(x) (ROTR(x,17)^ROTR(x,19)^((x)>>10))
+
+static uint32 const sha256_constants[64] =
+{
+  0x428a2f98UL, 0x71374491UL, 0xb5c0fbcfUL, 0xe9b5dba5UL,
+  0x3956c25bUL, 0x59f111f1UL, 0x923f82a4UL, 0xab1c5ed5UL,
+  0xd807aa98UL, 0x12835b01UL, 0x243185beUL, 0x550c7dc3UL,
+  0x72be5d74UL, 0x80deb1feUL, 0x9bdc06a7UL, 0xc19bf174UL,
+  0xe49b69c1UL, 0xefbe4786UL, 0x0fc19dc6UL, 0x240ca1ccUL,
+  0x2de92c6fUL, 0x4a7484aaUL, 0x5cb0a9dcUL, 0x76f988daUL,
+  0x983e5152UL, 0xa831c66dUL, 0xb00327c8UL, 0xbf597fc7UL,
+  0xc6e00bf3UL, 0xd5a79147UL, 0x06ca6351UL, 0x14292967UL,
+  0x27b70a85UL, 0x2e1b2138UL, 0x4d2c6dfcUL, 0x53380d13UL,
+  0x650a7354UL, 0x766a0abbUL, 0x81c2c92eUL, 0x92722c85UL,
+  0xa2bfe8a1UL, 0xa81a664bUL, 0xc24b8b70UL, 0xc76c51a3UL,
+  0xd192e819UL, 0xd6990624UL, 0xf40e3585UL, 0x106aa070UL,
+  0x19a4c116UL, 0x1e376c08UL, 0x2748774cUL, 0x34b0bcb5UL,
+  0x391c0cb3UL, 0x4ed8aa4aUL, 0x5b9cca4fUL, 0x682e6ff3UL,
+  0x748f82eeUL, 0x78a5636fUL, 0x84c87814UL, 0x8cc70208UL,
+  0x90befffaUL, 0xa4506cebUL, 0xbef9a3f7UL, 0xc67178f2UL
+} ;
+
+void sha256_transform (uint32 *buf, uint32 const *in)
+{
+  uint32 w[64] ;
+  unsigned int i = 0 ;
+  register uint32 a = buf[0], b = buf[1], c = buf[2], d = buf[3], e = buf[4], f = buf[5], g = buf[6], h = buf[7] ;
+
+  for (; i < 16 ; i++) w[i] = in[i] ;
+  for (; i < 64 ; i++)
+    w[i] = SMALLSIGMA1(w[i-2]) + w[i-7] + SMALLSIGMA0(w[i-15]) + w[i-16] ;
+  for (i = 0 ; i < 64 ; i++)
+  {
+    uint32 temp1 = h + CAPITALSIGMA1(e) + F1(e, f, g) + sha256_constants[i] + w[i] ;
+    uint32 temp2 = CAPITALSIGMA0(a) + F2(a, b, c) ;
+    h = g ; g = f ; f = e ; e = d + temp1 ;
+    d = c ; c = b ; b = a ; a = temp1 + temp2 ;
+  }
+  buf[0] += a ; buf[1] += b ; buf[2] += c ; buf[3] += d ;
+  buf[4] += e ; buf[5] += f ; buf[6] += g ; buf[7] += h ;
+}