diff options
Diffstat (limited to 'c/src/exec/libnetworking/net/ethernet.h')
-rw-r--r-- | c/src/exec/libnetworking/net/ethernet.h | 63 |
1 files changed, 63 insertions, 0 deletions
diff --git a/c/src/exec/libnetworking/net/ethernet.h b/c/src/exec/libnetworking/net/ethernet.h new file mode 100644 index 0000000000..c6c07189ec --- /dev/null +++ b/c/src/exec/libnetworking/net/ethernet.h @@ -0,0 +1,63 @@ +/* + * Fundamental constants relating to ethernet. + * + * $Id$ + * + */ + +#ifndef _NET_ETHERNET_H_ +#define _NET_ETHERNET_H_ + +/* + * The number of bytes in an ethernet (MAC) address. + */ +#define ETHER_ADDR_LEN 6 + +/* + * The number of bytes in the type field. + */ +#define ETHER_TYPE_LEN 2 + +/* + * The number of bytes in the trailing CRC field. + */ +#define ETHER_CRC_LEN 4 + +/* + * The length of the combined header. + */ +#define ETHER_HDR_LEN (ETHER_ADDR_LEN*2+ETHER_TYPE_LEN) + +/* + * The minimum packet length. + */ +#define ETHER_MIN_LEN 64 + +/* + * The maximum packet length. + */ +#define ETHER_MAX_LEN 1518 + +/* + * A macro to validate a length with + */ +#define ETHER_IS_VALID_LEN(foo) \ + ((foo) >= ETHER_MIN_LEN && (foo) <= ETHER_MAX_LEN) + +/* + * Structure of a 10Mb/s Ethernet header. + */ +struct ether_header { + u_char ether_dhost[ETHER_ADDR_LEN]; + u_char ether_shost[ETHER_ADDR_LEN]; + u_short ether_type; +}; + +/* + * Structure of a 48-bit Ethernet address. + */ +struct ether_addr { + u_char octet[ETHER_ADDR_LEN]; +}; + +#endif |