First commit

Signed-off-by: Mattias Andrée <maandree@kth.se>

1 files changed, 46 insertions, 0 deletions

diff --git a/init.c b/init.c
new file mode 100644
index 0000000..4e31556
--- /dev/null
+++ b/init.c
@@ -0,0 +1,46 @@
+/* See LICENSE file for copyright and license details. */
+#include "common.h"
+
+
+/**
+ * Initial state for SHA-0
+ */
+static const uint32_t H_0[] = {
+	0, 0, 0, 0, 0
+};
+
+/**
+ * Initial state for SHA_1
+ */
+static const uint32_t H_1[] = {
+	0x67452301UL, 0xEFCDAB89UL, 0x98BADCFEUL, 0x10325476UL, 0xC3D2E1F0UL
+};
+
+
+/**
+ * Initialise a state
+ * 
+ * @param   state      The state that should be initialised
+ * @param   algorithm  The hashing algorithm
+ * @return             Zero on success, -1 on error
+ */
+int
+libsha1_init(struct libsha1_state *restrict state, enum libsha1_algorithm algorithm)
+{
+	memset(state, 0, sizeof(*state));
+	state->message_size = 0;
+	state->algorithm = algorithm;
+
+	/* Set initial hash values. */
+	switch (algorithm) {
+	case LIBSHA1_0: memcpy(state->h, H_0, sizeof(H_0)); break;
+	case LIBSHA1_1: memcpy(state->h, H_1, sizeof(H_1)); break;
+	default:
+		errno = EINVAL;
+		return -1;
+	}
+
+	state->chunk_size = 64;
+  
+	return 0;
+}