From 93ca5ff7030aaf1219e1de05ec89a68384bfc50b Mon Sep 17 00:00:00 2001 From: Guy Harris Date: Thu, 25 Aug 2016 13:26:43 -0700 Subject: On Linux, handle all CAN captures with pcap-linux.c, in cooked mode. There's no need to support capturing on PF_CAN sockets; CAN interfaces show up as regular interfaces on which you can capture with PF_PACKET sockets, so just let pcap-linux.c handle them, and get rid of pcap-can-linux.c. Capture on them in cooked mode, so we get the protocol field and can distinguish between "classic" CAN and CAN FD. The hardware for which pcap-canusb-linux.c was intended never reached production: https://github.com/axos88/libpcap/commit/f3edbb599b8cbcc7e4560000dcba8e992dc11a31#commitcomment-18716617 so we don't need pcap-canusb-linux.c, either. This all removes the need for the "host-endian" link-layer header type; it never made it into a libpcap release, so we just remove it. The "big-endian" link-layer header type is kept for the benefit of packets captured with the old pcap-can-linux.c code; we revert it to its old name. --- pcap-linux.c | 22 ++++++---------------- 1 file changed, 6 insertions(+), 16 deletions(-) (limited to 'pcap-linux.c') diff --git a/pcap-linux.c b/pcap-linux.c index a2ace7b7..b7fb6889 100644 --- a/pcap-linux.c +++ b/pcap-linux.c @@ -2944,23 +2944,13 @@ static void map_arphrd_to_dlt(pcap_t *handle, int sock_fd, int arptype, #endif case ARPHRD_CAN: /* - * DLT_CAN_SOCKETCAN_BIGENDIAN is defined to have the - * can_id field of the pseudo-header in big-endian - * (network) byte order. - * - * The packets delivered to sockets have that field - * in host byte order. - * - * The code that implements it in packet-can-linux.c - * passes that field to htonl() to put it into network - * byte order. - * - * The code that reads from a PF_PACKET socket doesn't - * change the byte order of that field, so we define - * a new DLT_CAN_SOCKETCAN_HOSTENDIAN, where the can_id - * is in host byte order. + * Map this to DLT_LINUX_SLL; that way, CAN frames will + * have ETH_P_CAN/LINUX_SLL_P_CAN as the protocol and + * CAN FD frames will have ETH_P_CANFD/LINUX_SLL_P_CANFD + * as the protocol, so they can be distinguished by the + * protocol in the SLL header. */ - handle->linktype = DLT_CAN_SOCKETCAN_HOSTENDIAN; + handle->linktype = DLT_LINUX_SLL; break; #ifndef ARPHRD_IEEE802_TR -- cgit v1.2.3