Revert "isisd: bpf: ETHER_HDR_LEN -> ETH_ALEN"

This reverts commit d9e5b009554f99230be1eee62daf098403c3cadf.

ETH_ALEN is not equivalent to ETHER_HDR_LEN. ETHER_HDR_LEN is the
definition for the length of the full ethernet header, meanwhile
ETH_ALEN is just the length of the ethernet address.

Here is the OpenBSD/FreeBSD definition for ETHER_HDR_LEN:
 #define ETHER_ADDR_LEN  6       /* Ethernet address length */
 #define ETHER_TYPE_LEN  2       /* Ethernet type field length */
 #define ETHER_HDR_LEN   ((ETHER_ADDR_LEN * 2) + ETHER_TYPE_LEN)

(OpenBSD's definition is at net/if_ether.h, FreeBSD's is at
 net/ethernet.h)

Linux definitions can be found at: net/ethernet.h
 #define ETHER_ADDR_LEN  ETH_ALEN  /* size of ethernet addr */
 #define ETHER_TYPE_LEN  2         /* bytes in type field */
 #define ETHER_HDR_LEN   ETH_HLEN  /* total octets in header */

net/if_ether.h:
 #define ETH_HLEN       14 /* Total octets in header.       */
 #define ETH_ALEN       6  /* Octets in one ethernet addr   */

Signed-off-by: Rafael Zalamena <rzalamena@opensourcerouting.org>

diff --git a/isisd/isis_bpf.c b/isisd/isis_bpf.c
index 591af3b8eddf3a3dbc813b948a79a95b6d2cf7ed..a4c6b4c75d055a3e6e089b02e237c11defc00c7a 100644 (file)
--- a/isisd/isis_bpf.c
+++ b/isisd/isis_bpf.c
@@ -46,15 +46,14 @@
 #include "privs.h"
 
 struct bpf_insn llcfilter[] = {
-       /* check first byte */
-       BPF_STMT(BPF_LD + BPF_B + BPF_ABS, ETH_ALEN),
+       BPF_STMT(BPF_LD + BPF_B + BPF_ABS,
+                ETHER_HDR_LEN), /* check first byte */
        BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ISO_SAP, 0, 5),
-       /* check second byte */
-       BPF_STMT(BPF_LD + BPF_B + BPF_ABS, ETH_ALEN + 1),
-       BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ISO_SAP, 0, 3),
-       /* check third byte */
-       BPF_STMT(BPF_LD + BPF_B + BPF_ABS, ETH_ALEN + 2),
-       BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0x03, 0, 1),
+       BPF_STMT(BPF_LD + BPF_B + BPF_ABS, ETHER_HDR_LEN + 1),
+       BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, ISO_SAP, 0,
+                3), /* check second byte */
+       BPF_STMT(BPF_LD + BPF_B + BPF_ABS, ETHER_HDR_LEN + 2),
+       BPF_JUMP(BPF_JMP + BPF_JEQ + BPF_K, 0x03, 0, 1), /* check third byte */
        BPF_STMT(BPF_RET + BPF_K, (u_int)-1),
        BPF_STMT(BPF_RET + BPF_K, 0)};
 u_int readblen = 0;
@@ -242,14 +241,15 @@ int isis_recv_pdu_bcast(struct isis_circuit *circuit, u_char *ssnpa)
 
        assert(bpf_hdr->bh_caplen == bpf_hdr->bh_datalen);
 
-       offset = bpf_hdr->bh_hdrlen + LLC_LEN + ETH_ALEN;
+       offset = bpf_hdr->bh_hdrlen + LLC_LEN + ETHER_HDR_LEN;
 
        /* then we lose the BPF, LLC and ethernet headers */
        stream_write(circuit->rcv_stream, readbuff + offset,
-                    bpf_hdr->bh_caplen - LLC_LEN - ETH_ALEN);
+                    bpf_hdr->bh_caplen - LLC_LEN - ETHER_HDR_LEN);
        stream_set_getp(circuit->rcv_stream, 0);
 
-       memcpy(ssnpa, readbuff + bpf_hdr->bh_hdrlen + ETH_ALEN, ETH_ALEN);
+       memcpy(ssnpa, readbuff + bpf_hdr->bh_hdrlen + ETH_ALEN,
+              ETH_ALEN);
 
        if (ioctl(circuit->fd, BIOCFLUSH, &one) < 0)
                zlog_warn("Flushing failed: %s", safe_strerror(errno));
@@ -263,7 +263,7 @@ int isis_send_pdu_bcast(struct isis_circuit *circuit, int level)
        ssize_t written;
        size_t buflen;
 
-       buflen = stream_get_endp(circuit->snd_stream) + LLC_LEN + ETH_ALEN;
+       buflen = stream_get_endp(circuit->snd_stream) + LLC_LEN + ETHER_HDR_LEN;
        if (buflen > sizeof(sock_buff)) {
                zlog_warn(
                        "isis_send_pdu_bcast: sock_buff size %zu is less than "
@@ -289,12 +289,12 @@ int isis_send_pdu_bcast(struct isis_circuit *circuit, int level)
        /*
         * Then the LLC
         */
-       sock_buff[ETH_ALEN] = ISO_SAP;
-       sock_buff[ETH_ALEN + 1] = ISO_SAP;
-       sock_buff[ETH_ALEN + 2] = 0x03;
+       sock_buff[ETHER_HDR_LEN] = ISO_SAP;
+       sock_buff[ETHER_HDR_LEN + 1] = ISO_SAP;
+       sock_buff[ETHER_HDR_LEN + 2] = 0x03;
 
        /* then we copy the data */
-       memcpy(sock_buff + (LLC_LEN + ETH_ALEN), circuit->snd_stream->data,
+       memcpy(sock_buff + (LLC_LEN + ETHER_HDR_LEN), circuit->snd_stream->data,
               stream_get_endp(circuit->snd_stream));
 
        /* now we can send this */