/*      $OpenBSD: print-ether.c,v 1.42 2022/06/09 12:56:14 mbuhl Exp $  */

/*
 * Copyright (c) 1988, 1989, 1990, 1991, 1992, 1993, 1994, 1995, 1996, 1997
 *      The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that: (1) source code distributions
 * retain the above copyright notice and this paragraph in its entirety, (2)
 * distributions including binary code include the above copyright notice and
 * this paragraph in its entirety in the documentation or other materials
 * provided with the distribution, and (3) all advertising materials mentioning
 * features or use of this software display the following acknowledgement:
 * ``This product includes software developed by the University of California,
 * Lawrence Berkeley Laboratory and its contributors.'' Neither the name of
 * the University nor the names of its contributors may be used to endorse
 * or promote products derived from this software without specific prior
 * written permission.
 * THIS SOFTWARE IS PROVIDED ``AS IS'' AND WITHOUT ANY EXPRESS OR IMPLIED
 * WARRANTIES, INCLUDING, WITHOUT LIMITATION, THE IMPLIED WARRANTIES OF
 * MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE.
 */

#include <sys/time.h>
#include <sys/socket.h>

#include <net/if.h>

#include <netinet/in.h>
#include <netinet/if_ether.h>
#include <netinet/ip.h>
#include <netinet/ip6.h>
#include <netinet/ip_var.h>
#include <netinet/udp.h>
#include <netinet/udp_var.h>
#include <netinet/tcp.h>

#include <stdio.h>
#include <stddef.h>
#include <pcap.h>


#include "interface.h"
#include "addrtoname.h"
#include "ethertype.h"
#include "extract.h"

const u_char *packetp;
const u_char *snapend;

void ether_macctl(const u_char *, u_int);
void ether_pbb_print(const u_char *, u_int, u_int);
void ether_eapol_print(const u_char *, u_int, u_int);

void
ether_print(const u_char *bp, u_int length)
{
        const struct ether_header *ep;

        ep = (const struct ether_header *)bp;
        if (qflag) {
                TCHECK2(*ep, 12);
                printf("%s %s %d: ",
                    etheraddr_string(ESRC(ep)),
                    etheraddr_string(EDST(ep)),
                    length);
        } else {
                TCHECK2(*ep, 14);
                printf("%s %s %s %d: ",
                    etheraddr_string(ESRC(ep)),
                    etheraddr_string(EDST(ep)),
                    etherproto_string(ep->ether_type),
                    length);
        }
        return;
trunc:
        printf("[|ether] ");
}

u_short extracted_ethertype;

/*
 * This is the top level routine of the printer.  'p' is the points
 * to the ether header of the packet, 'tvp' is the timestamp,
 * 'length' is the length of the packet off the wire, and 'caplen'
 * is the number of bytes actually captured.
 */
void
ether_if_print(u_char *user, const struct pcap_pkthdr *h, const u_char *p)
{
        ts_print(&h->ts);

        /*
         * Some printers want to get back at the ethernet addresses,
         * and/or check that they're not walking off the end of the packet.
         * Rather than pass them all the way down, we set these globals.
         */
        snapend = p + h->caplen;

        ether_tryprint(p, h->len, 1);
}

void
ether_tryprint(const u_char *p, u_int length, int first_header)
{
        struct ether_header *ep;
        u_int caplen = snapend - p;
        u_short ether_type;

        if (caplen < sizeof(struct ether_header)) {
                printf("[|ether]");
                goto out;
        }

        if (eflag)
                ether_print(p, length);

        packetp = p;
        length -= sizeof(struct ether_header);
        caplen -= sizeof(struct ether_header);
        ep = (struct ether_header *)p;
        p += sizeof(struct ether_header);

        ether_type = ntohs(ep->ether_type);

        /*
         * Is it (gag) an 802.3 encapsulation?
         */
        extracted_ethertype = 0;
        if (ether_type <= ETHERMTU) {
                /* Try to print the LLC-layer header & higher layers */
                if (llc_print(p, length, caplen, ESRC(ep), EDST(ep)) == 0) {
                        /* ether_type not known, print raw packet */
                        if (!eflag)
                                ether_print((u_char *)ep, length);
                        if (extracted_ethertype) {
                                printf("(LLC %s) ",
                               etherproto_string(htons(extracted_ethertype)));
                        }
                        if (!xflag && !qflag) {
                                if (eflag)
                                        default_print(packetp,
                                            snapend - packetp);
                                else
                                        default_print(p, caplen);
                        }
                }
        } else if (ether_encap_print(ether_type, p, length, caplen) == 0) {
                /* ether_type not known, print raw packet */
                if (!eflag)
                        ether_print((u_char *)ep, length + sizeof(*ep));
                if (!xflag && !qflag) {
                        if (eflag)
                                default_print(packetp, snapend - packetp);
                        else
                                default_print(p, caplen);
                }
        }
        if (xflag && first_header) {
                if (eflag)
                        default_print(packetp, snapend - packetp);
                else
                        default_print(p, caplen);
        }
 out:
        if (first_header)
                putchar('\n');
}

void
ether_pbb_print(const u_char *bp, u_int length, u_int caplen)
{
        uint32_t itag;
        uint8_t pri, res;

        if (caplen < sizeof(itag))
                goto trunc;

        itag = EXTRACT_32BITS(bp);

        bp += sizeof(itag);
        length -= sizeof(itag);
        caplen -= sizeof(itag);

        pri = itag >> 29;
        if (pri <= 1)
                pri = !pri;

        res = (itag >> 24) & 0x7;

        printf("802.1Q ivid %u pri %u ", itag & 0xffffff, pri);
        if (itag & (1 << 28))
                printf("dei ");
        if (itag & (1 << 27))
                printf("uca ");
        if (res)
                printf("res %u! ", res);

        ether_tryprint(bp, length, 0);

        return;

trunc:
        printf("[|pbb] ");
}

/*
 * Prints the packet encapsulated in an Ethernet data segment
 * (or an equivalent encapsulation), given the Ethernet type code.
 *
 * Returns non-zero if it can do so, zero if the ethertype is unknown.
 *
 * Stuffs the ether type into a global for the benefit of lower layers
 * that might want to know what it is.
 */

int
ether_encap_print(u_short ethertype, const u_char *p,
    u_int length, u_int caplen)
{
        uint16_t vlan, pri, vid;
recurse:
        extracted_ethertype = ethertype;

        switch (ethertype) {

        case ETHERTYPE_IP:
                ip_print(p, length);
                return (1);

        case ETHERTYPE_IPV6:
                ip6_print(p, length);
                return (1);

        case ETHERTYPE_ARP:
        case ETHERTYPE_REVARP:
                arp_print(p, length, caplen);
                return (1);

        case ETHERTYPE_DN:
                decnet_print(p, length, caplen);
                return (1);

        case ETHERTYPE_ATALK:
                if (vflag)
                        printf("et1 ");
                atalk_print_llap(p, length);
                return (1);

        case ETHERTYPE_AARP:
                aarp_print(p, length);
                return (1);

        case ETHERTYPE_8021Q:
                printf("802.1Q ");
        case ETHERTYPE_QINQ:
                if (ethertype == ETHERTYPE_QINQ)
                        printf("QinQ s");

                /* XXX caplen check */

                vlan = ntohs(*(unsigned short*)p);
                vid = vlan & 0xfff;
                pri = vlan >> 13;
                if (pri <= 1)
                        pri = !pri;

                printf("vid %d pri %d%s", vid, pri,
                    vlan & 0x1000 ? " dei " : " ");
                ethertype = ntohs(*(unsigned short*)(p+2));
                p += 4;
                length -= 4;
                caplen -= 4;
                if (ethertype > ETHERMTU) 
                        goto recurse;

                extracted_ethertype = 0;

                if (llc_print(p, length, caplen, p-18, p-12) == 0) {
                        /* ether_type not known, print raw packet */
                        if (!eflag)
                                ether_print(p-18, length+4);
                        if (extracted_ethertype) {
                                printf("(LLC %s) ",
                                etherproto_string(htons(extracted_ethertype)));
                        }
                        if (!xflag && !qflag)
                                default_print(p-18, caplen+4);
                }
                return (1);

        case ETHERTYPE_NSH:
                nsh_print(p, length);
                return (1);

        case ETHERTYPE_EAPOL:
                ether_eapol_print(p, length, caplen);
                return (1);

        case ETHERTYPE_PBB:
                ether_pbb_print(p, length, caplen);
                return (1);

        case ETHERTYPE_NHRP:
                nhrp_print(p, length);
                return (1);

#ifdef PPP
        case ETHERTYPE_PPPOEDISC:
        case ETHERTYPE_PPPOE:
                pppoe_if_print(ethertype, p, length, caplen);
                return (1);
#endif

        case ETHERTYPE_FLOWCONTROL:
                ether_macctl(p, length);
                return (1);

        case ETHERTYPE_MPLS:
        case ETHERTYPE_MPLS_MCAST:
                mpls_print(p, length);
                return (1);

        case ETHERTYPE_LLDP:
                lldp_print(p, length);
                return (1);

        case ETHERTYPE_SLOW:
                slow_print(p, length);
                return (1);

        case ETHERTYPE_LAT:
        case ETHERTYPE_SCA:
        case ETHERTYPE_MOPRC:
        case ETHERTYPE_MOPDL:
                /* default_print for now */
        default:
                return (0);
        }
}

void
ether_macctl(const u_char *p, u_int length)
{
        printf("MACCTL");

        if (length < 2)
                goto trunc;
        if (EXTRACT_16BITS(p) == 0x0001) {
                u_int plen;

                printf(" PAUSE");

                length -= 2;
                p += 2;
                if (length < 2)
                        goto trunc;
                plen = 512 * EXTRACT_16BITS(p);
                printf(" quanta %u", plen);
        } else {
                printf(" unknown-opcode(0x%04x)", EXTRACT_16BITS(p));
        }
        return;

trunc:
        printf("[|MACCTL]");
}

/*
 * 802.1X EAPOL PDU
 */

struct eapol_header {
        uint8_t                 version;
        uint8_t                 type;
#define EAPOL_T_EAP                     0x00
#define EAPOL_T_START                   0x01
#define EAPOL_T_LOGOFF                  0x02
#define EAPOL_T_KEY                     0x03
#define EAPOL_T_ENCAP_ASF_ALERT         0x04
#define EAPOL_T_MKA                     0x05
#define EAPOL_T_ANNOUNCEMENT_GENERIC    0x06
#define EAPOL_T_ANNOUNCEMENT_SPECIFIC   0x07
#define EAPOL_T_ANNOUNCEMENT_REQ        0x08
        uint16_t                length;
};

void
ether_eapol_print(const u_char *bp, u_int length, u_int caplen)
{
        struct eapol_header h;

        printf("EAPOL");

        if (caplen < sizeof(h))
                goto trunc;

        h.version = *(bp + offsetof(struct eapol_header, version));
        h.type = *(bp + offsetof(struct eapol_header, type));
        h.length = EXTRACT_16BITS(bp + offsetof(struct eapol_header, length));

        bp += sizeof(h);
        length -= sizeof(h);
        caplen -= sizeof(h);

        if (vflag)
                printf(" (v%u, len %u)", h.version, h.length);

        if (length > h.length)
                length = h.length;
        else if (length < h.length) {
                printf(" truncated-eapol - %u bytes missing!",
                    h.length - length);
        }

        switch (h.type) {
        case EAPOL_T_EAP:
                printf(" EAP");
                break;
        case EAPOL_T_START:
                printf(" Start");
                break;
        case EAPOL_T_LOGOFF:
                printf(" Logoff");
                break;
        case EAPOL_T_KEY:
                printf(" Key");
                break;
        case EAPOL_T_MKA:
                printf(" MKA");
                break;
        case EAPOL_T_ANNOUNCEMENT_GENERIC:
                printf(" Announcement (Generic)");
                break;
        case EAPOL_T_ANNOUNCEMENT_SPECIFIC:
                printf(" Announcement (Specific)");
                break;
        case EAPOL_T_ANNOUNCEMENT_REQ:
                printf(" Announcement Req");
                break;
        default:
                printf(" unknown (%u)", h.type);
                break;
        }

        return;

trunc:
        printf(" [|eapol] ");
}