1 files changed, 74 insertions, 0 deletions
diff --git a/lib/checksum.h b/lib/checksum.h
new file mode 100644
index 0000000..508c3f3
--- /dev/null
+++ b/lib/checksum.h
@@ -0,0 +1,74 @@
+#ifndef _FRR_CHECKSUM_H
+#define _FRR_CHECKSUM_H
+
+#include <stdint.h>
+#include <netinet/in.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+
+/* IPv4 pseudoheader */
+struct ipv4_ph {
+	struct in_addr src;
+	struct in_addr dst;
+	uint8_t rsvd;
+	uint8_t proto;
+	uint16_t len;
+} __attribute__((packed));
+
+/* IPv6 pseudoheader */
+struct ipv6_ph {
+	struct in6_addr src;
+	struct in6_addr dst;
+	uint32_t ulpl;
+	uint8_t zero[3];
+	uint8_t next_hdr;
+} __attribute__((packed));
+
+
+extern uint16_t in_cksumv(const struct iovec *iov, size_t iov_len);
+
+static inline uint16_t in_cksum(const void *data, size_t nbytes)
+{
+	struct iovec iov[1];
+
+	iov[0].iov_base = (void *)data;
+	iov[0].iov_len = nbytes;
+	return in_cksumv(iov, array_size(iov));
+}
+
+static inline uint16_t in_cksum_with_ph4(const struct ipv4_ph *ph,
+					 const void *data, size_t nbytes)
+{
+	struct iovec iov[2];
+
+	iov[0].iov_base = (void *)ph;
+	iov[0].iov_len = sizeof(*ph);
+	iov[1].iov_base = (void *)data;
+	iov[1].iov_len = nbytes;
+	return in_cksumv(iov, array_size(iov));
+}
+
+static inline uint16_t in_cksum_with_ph6(const struct ipv6_ph *ph,
+					 const void *data, size_t nbytes)
+{
+	struct iovec iov[2];
+
+	iov[0].iov_base = (void *)ph;
+	iov[0].iov_len = sizeof(*ph);
+	iov[1].iov_base = (void *)data;
+	iov[1].iov_len = nbytes;
+	return in_cksumv(iov, array_size(iov));
+}
+
+#define FLETCHER_CHECKSUM_VALIDATE 0xffff
+extern uint16_t fletcher_checksum(uint8_t *, const size_t len,
+				  const uint16_t offset);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _FRR_CHECKSUM_H */