lib: use iovec for checksum code

... to allow checksumming noncontiguous blurbs of data.

Signed-off-by: David Lamparter <equinox@opensourcerouting.org>

1 files changed, 35 insertions, 3 deletions

diff --git a/lib/checksum.h b/lib/checksum.h
index 16e6945422..508c3f38a6 100644
--- a/lib/checksum.h
+++ b/lib/checksum.h
@@ -27,9 +27,41 @@ struct ipv6_ph {
 	uint8_t next_hdr;
 } __attribute__((packed));
 
-extern int in_cksum(void *data, int nbytes);
-extern int in_cksum_with_ph4(struct ipv4_ph *ph, void *data, int nbytes);
-extern int in_cksum_with_ph6(struct ipv6_ph *ph, void *data, int nbytes);
+
+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,