22 #include "checksum.h"
30  * calculates the checksum over all the packet components starting from pos
31  * checksum - checksum of packet components before pos
32  * packet   - packet to calculate the checksum of
34  * returns  - the completed 16-bit checksum, ready to write into a checksum header field
36 uint16_t packet_checksum(uint32_t checksum, clat_packet packet, clat_packet_index pos) {  in packet_checksum()  argument
40       checksum = ip_checksum_add(checksum, packet[i].iov_base, packet[i].iov_len);  in packet_checksum()
43   return ip_checksum_finish(checksum);  in packet_checksum()
222  * checksum     - pseudo-header checksum
228                   uint32_t checksum, const uint8_t *payload, size_t payload_size) {  in icmp_to_icmp6()  argument
248     // The pseudo-header checksum was calculated on the transport length of the original IPv4  in icmp_to_icmp6()
253     // pseudo-header when calculating its checksum (as the IPv4 header has its own checksum).  in icmp_to_icmp6()
254     checksum = checksum + htons(20);  in icmp_to_icmp6()
267   icmp6_targ->icmp6_cksum = 0;  // Checksum field must be 0 when calculating checksum.  in icmp_to_icmp6()
268   icmp6_targ->icmp6_cksum = packet_checksum(checksum, out, pos);  in icmp_to_icmp6()
313   icmp_targ->checksum = 0;  // Checksum field must be 0 when calculating checksum.  in icmp6_to_icmp()
314   icmp_targ->checksum = packet_checksum(0, out, pos);  in icmp6_to_icmp()
339  * old_sum  - pseudo-header checksum of old header
340  * new_sum  - pseudo-header checksum of new header
363  * checksum - pseudo-header checksum
395  * common between ipv4/ipv6 - setup checksum and send udp packet
398  * old_sum      - pseudo-header checksum of old header
399  * new_sum      - pseudo-header checksum of new header
417     // Zero checksums are special. RFC 768 says, "An all zero transmitted checksum value means that  in udp_translate()
418     // the transmitter generated no checksum (for debugging or for higher level protocols that  in udp_translate()
421     udp_targ->check = 0;  // Checksum field must be 0 when calculating checksum.  in udp_translate()
425   // RFC 768: "If the computed checksum is zero, it is transmitted as all ones (the equivalent  in udp_translate()
435  * common between ipv4/ipv6 - setup checksum and send tcp packet
439  * checksum     - partial checksum covering ipv4/ipv6 header