--- /dev/null
+/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
+ * Junior University
+ *
+ * We are making the OpenFlow specification and associated documentation
+ * (Software) available for public use and benefit with the expectation
+ * that others will use, modify and enhance the Software and contribute
+ * those enhancements back to the community. However, since we would
+ * like to make the Software available for broadest use, with as few
+ * restrictions as possible permission is hereby granted, free of
+ * charge, to any person obtaining a copy of this Software to deal in
+ * the Software under the copyrights without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * The name and trademarks of copyright holder(s) may NOT be used in
+ * advertising or publicity pertaining to the Software or any
+ * derivatives without specific, written prior permission.
+ */
+
+#ifndef CSUM_H
+#define CSUM_H 1
+
+#include <stddef.h>
+#include <stdint.h>
+
+uint16_t csum(const void *, size_t);
+uint32_t csum_add16(uint32_t partial, uint16_t);
+uint32_t csum_add32(uint32_t partial, uint32_t);
+uint32_t csum_continue(uint32_t partial, const void *, size_t);
+uint16_t csum_finish(uint32_t partial);
+uint16_t recalc_csum16(uint16_t old_csum, uint16_t old_u16, uint16_t new_u16);
+uint16_t recalc_csum32(uint16_t old_csum, uint32_t old_u32, uint32_t new_u32);
+
+#endif /* csum.h */
--- /dev/null
+/* Copyright (c) 2008 The Board of Trustees of The Leland Stanford
+ * Junior University
+ *
+ * We are making the OpenFlow specification and associated documentation
+ * (Software) available for public use and benefit with the expectation
+ * that others will use, modify and enhance the Software and contribute
+ * those enhancements back to the community. However, since we would
+ * like to make the Software available for broadest use, with as few
+ * restrictions as possible permission is hereby granted, free of
+ * charge, to any person obtaining a copy of this Software to deal in
+ * the Software under the copyrights without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ *
+ * The name and trademarks of copyright holder(s) may NOT be used in
+ * advertising or publicity pertaining to the Software or any
+ * derivatives without specific, written prior permission.
+ */
+
+#include "csum.h"
+
+/* Returns the IP checksum of the 'n' bytes in 'data'. */
+uint16_t
+csum(const void *data, size_t n)
+{
+ return csum_finish(csum_continue(0, data, n));
+}
+
+/* Adds the 16 bits in 'new' to the partial IP checksum 'partial' and returns
+ * the updated checksum. (To start a new checksum, pass 0 for 'partial'. To
+ * obtain the finished checksum, pass the return value to csum_finish().) */
+uint32_t
+csum_add16(uint32_t partial, uint16_t new)
+{
+ return partial + new;
+}
+
+/* Adds the 32 bits in 'new' to the partial IP checksum 'partial' and returns
+ * the updated checksum. (To start a new checksum, pass 0 for 'partial'. To
+ * obtain the finished checksum, pass the return value to csum_finish().) */
+uint32_t
+csum_add32(uint32_t partial, uint32_t new)
+{
+ return partial + (new >> 16) + (new & 0xffff);
+}
+
+
+/* Adds the 'n' bytes in 'data' to the partial IP checksum 'partial' and
+ * returns the updated checksum. (To start a new checksum, pass 0 for
+ * 'partial'. To obtain the finished checksum, pass the return value to
+ * csum_finish().) */
+uint32_t
+csum_continue(uint32_t partial, const void *data_, size_t n)
+{
+ const uint16_t *data = data_;
+
+ for (; n > 1; n -= 2) {
+ partial = csum_add16(partial, *data++);
+ }
+ if (n) {
+ partial += *(uint8_t *) data;
+ }
+ return partial;
+}
+
+/* Returns the IP checksum corresponding to 'partial', which is a value updated
+ * by some combination of csum_add16(), csum_add32(), and csum_continue(). */
+uint16_t
+csum_finish(uint32_t partial)
+{
+ return ~((partial & 0xffff) + (partial >> 16));
+}
+
+/* Returns the new checksum for a packet in which the checksum field previously
+ * contained 'old_csum' and in which a field that contained 'old_u16' was
+ * changed to contain 'new_u16'. */
+uint16_t
+recalc_csum16(uint16_t old_csum, uint16_t old_u16, uint16_t new_u16)
+{
+ /* Ones-complement arithmetic is endian-independent, so this code does not
+ * use htons() or ntohs().
+ *
+ * See RFC 1624 for formula and explanation. */
+ uint16_t hc_complement = ~old_csum;
+ uint16_t m_complement = ~old_u16;
+ uint16_t m_prime = new_u16;
+ uint32_t sum = hc_complement + m_complement + m_prime;
+ uint16_t hc_prime_complement = sum + (sum >> 16);
+ return ~hc_prime_complement;
+}
+
+/* Returns the new checksum for a packet in which the checksum field previously
+ * contained 'old_csum' and in which a field that contained 'old_u32' was
+ * changed to contain 'new_u32'. */
+uint16_t
+recalc_csum32(uint16_t old_csum, uint32_t old_u32, uint32_t new_u32)
+{
+ return recalc_csum16(recalc_csum16(old_csum, old_u32, new_u32),
+ old_u32 >> 16, new_u32 >> 16);
+}
#include <string.h>
#include "buffer.h"
#include "chain.h"
+#include "csum.h"
#include "flow.h"
#include "netdev.h"
#include "packets.h"
buffer_delete(buffer);
}
-/* Returns the new checksum for a packet in which the checksum field previously
- * contained 'old_csum' and in which a field that contained 'old_u16' was
- * changed to contain 'new_u16'. */
-static uint16_t
-recalc_csum16(uint16_t old_csum, uint16_t old_u16, uint16_t new_u16)
-{
- /* Ones-complement arithmetic is endian-independent, so this code does not
- * use htons() or ntohs().
- *
- * See RFC 1624 for formula and explanation. */
- uint16_t hc_complement = ~old_csum;
- uint16_t m_complement = ~old_u16;
- uint16_t m_prime = new_u16;
- uint32_t sum = hc_complement + m_complement + m_prime;
- uint16_t hc_prime_complement = sum + (sum >> 16);
- return ~hc_prime_complement;
-}
-
-/* Returns the new checksum for a packet in which the checksum field previously
- * contained 'old_csum' and in which a field that contained 'old_u32' was
- * changed to contain 'new_u32'. */
-static uint16_t
-recalc_csum32(uint16_t old_csum, uint32_t old_u32, uint32_t new_u32)
-{
- return recalc_csum16(recalc_csum16(old_csum, old_u32, new_u32),
- old_u32 >> 16, new_u32 >> 16);
-}
-
static void modify_nh(struct buffer *buffer, uint16_t eth_proto,
uint8_t nw_proto, const struct ofp_action *a)
{
projects / openvswitch / commitdiff