Allow to checksum on-the-wire data using either CRC32 or SHA256.

MFC after:	2 weeks

1 files changed, 28 insertions, 0 deletions

diff --git a/sbin/hastd/crc32.h b/sbin/hastd/crc32.h
new file mode 100644
index 0000000..3812a83
--- /dev/null
+++ b/sbin/hastd/crc32.h
@@ -0,0 +1,28 @@
+/*-
+ *  COPYRIGHT (C) 1986 Gary S. Brown.  You may use this program, or
+ *  code or tables extracted from it, as desired without restriction.
+ *
+ * $FreeBSD$
+ */
+
+#ifndef _CRC32_H_
+#define	_CRC32_H_
+
+#include <stdint.h>	/* uint32_t */
+#include <stdlib.h>	/* size_t */
+
+extern uint32_t crc32_tab[];
+
+static __inline uint32_t
+crc32(const void *buf, size_t size)
+{
+	const uint8_t *p = buf;
+	uint32_t crc;
+
+	crc = ~0U;
+	while (size--)
+		crc = crc32_tab[(crc ^ *p++) & 0xFF] ^ (crc >> 8);
+	return (crc ^ ~0U);
+}
+
+#endif	/* !_CRC32_H_ */