1 files changed, 78 insertions, 0 deletions
diff --git a/src/sha1-generic.c b/src/sha1-generic.c
new file mode 100644
index 0000000..d897a8f
--- /dev/null
+++ b/src/sha1-generic.c
@@ -0,0 +1,78 @@
+#include "common.h"
+#include "sha1.h"
+#include "xendian.h"
+
+static inline uint32_t rotl32(uint32_t x, uint8_t bits)
+	__attribute__((always_inline, const));
+
+static const uint32_t K[] = {
+	0x5A827999,
+	0x6ED9EBA1,
+	0x8F1BBCDC,
+	0xCA62C1D6,
+};
+
+void
+sha1hashblk(sha1_t *s, const uint8_t *blk)
+{
+	uint32_t w[80];
+	uint32_t a, b, c, d, e, tmp;
+
+	for (int i = 0; i < 16; i++)
+		w[i] = htobe32(((uint32_t *)blk)[i]);
+	for (int i = 16; i < 32; i++)
+		w[i] = rotl32(w[i-3] ^ w[i-8] ^ w[i-14] ^ w[i-16], 1);
+	for (int i = 32; i < 80; i++)
+		w[i] = rotl32(w[i-6] ^ w[i-16] ^ w[i-28] ^ w[i-32], 2);
+
+	a = s->dgst[0];
+	b = s->dgst[1];
+	c = s->dgst[2];
+	d = s->dgst[3];
+	e = s->dgst[4];
+
+	for (int i = 0; i < 80; i++) {
+		uint32_t f, k;
+
+		if (i < 20) {
+			f = b&c | ~b&d;
+			k = K[0];
+		} else if (i < 40) {
+			f = b ^ c ^ d;
+			k = K[1];
+		} else if (i < 60) {
+			f = b&c | b&d | c&d;
+			k = K[2];
+		} else {
+			f = b ^ c ^ d;
+			k = K[3];
+		}
+
+		tmp = rotl32(a, 5) + f + e + w[i] + k;
+		e = d;
+		d = c;
+		c = rotl32(b, 30);
+		b = a;
+		a = tmp;
+	}
+
+	s->dgst[0] += a;
+	s->dgst[1] += b;
+	s->dgst[2] += c;
+	s->dgst[3] += d;
+	s->dgst[4] += e;
+}
+
+uint32_t
+rotl32(uint32_t x, uint8_t bits)
+{
+#if (__GNUC__ || __TINYC__) && __x86_64__
+	__asm__ ("roll %1, %0" : "+r" (x) : "c" (bits) : "cc");
+	return x;
+#elif __GNUC__ && __aarch64__ /* TODO: Test this! */
+	__asm__ ("ror %0, %0, %1" : "+r" (x) : "c" (-bits));
+	return x;
+#else
+	return (x << bits) | (x >> (32 - bits));
+#endif
+}