lib/checksum.h

   1 #ifndef _FRR_CHECKSUM_H
   2 #define _FRR_CHECKSUM_H
   3
   4 #include <stdint.h>
   5 #include <netinet/in.h>
   6
   7 #ifdef __cplusplus
   8 extern "C" {
   9 #endif
  10
  11
  12 /* IPv4 pseudoheader */
  13 struct ipv4_ph {
  14         struct in_addr src;
  15         struct in_addr dst;
  16         uint8_t rsvd;
  17         uint8_t proto;
  18         uint16_t len;
  19 } __attribute__((packed));
  20
  21 /* IPv6 pseudoheader */
  22 struct ipv6_ph {
  23         struct in6_addr src;
  24         struct in6_addr dst;
  25         uint32_t ulpl;
  26         uint8_t zero[3];
  27         uint8_t next_hdr;
  28 } __attribute__((packed));
  29
  30
  31 extern uint16_t in_cksumv(const struct iovec *iov, size_t iov_len);
  32
  33 static inline uint16_t in_cksum(const void *data, size_t nbytes)
  34 {
  35         struct iovec iov[1];
  36
  37         iov[0].iov_base = (void *)data;
  38         iov[0].iov_len = nbytes;
  39         return in_cksumv(iov, array_size(iov));
  40 }
  41
  42 static inline uint16_t in_cksum_with_ph4(const struct ipv4_ph *ph,
  43                                          const void *data, size_t nbytes)
  44 {
  45         struct iovec iov[2];
  46
  47         iov[0].iov_base = (void *)ph;
  48         iov[0].iov_len = sizeof(*ph);
  49         iov[1].iov_base = (void *)data;
  50         iov[1].iov_len = nbytes;
  51         return in_cksumv(iov, array_size(iov));
  52 }
  53
  54 static inline uint16_t in_cksum_with_ph6(const struct ipv6_ph *ph,
  55                                          const void *data, size_t nbytes)
  56 {
  57         struct iovec iov[2];
  58
  59         iov[0].iov_base = (void *)ph;
  60         iov[0].iov_len = sizeof(*ph);
  61         iov[1].iov_base = (void *)data;
  62         iov[1].iov_len = nbytes;
  63         return in_cksumv(iov, array_size(iov));
  64 }
  65
  66 #define FLETCHER_CHECKSUM_VALIDATE 0xffff
  67 extern uint16_t fletcher_checksum(uint8_t *, const size_t len,
  68                                   const uint16_t offset);
  69
  70 #ifdef __cplusplus
  71 }
  72 #endif
  73
  74 #endif /* _FRR_CHECKSUM_H */