[thirdparty/squid.git] / src / icmp / Icmp6.cc

/*
 * DEBUG: section 42    ICMP Pinger program
 * AUTHOR: Duane Wessels, Amos Jeffries
 *
 * SQUID Web Proxy Cache          http://www.squid-cache.org/
 * ----------------------------------------------------------
 *
 *  Squid is the result of efforts by numerous individuals from
 *  the Internet community; see the CONTRIBUTORS file for full
 *  details.   Many organizations have provided support for Squid's
 *  development; see the SPONSORS file for full details.  Squid is
 *  Copyrighted (C) 2001 by the Regents of the University of
 *  California; see the COPYRIGHT file for full details.  Squid
 *  incorporates software developed and/or copyrighted by other
 *  sources; see the CREDITS file for full details.
 *
 *  This program is free software; you can redistribute it and/or modify
 *  it under the terms of the GNU General Public License as published by
 *  the Free Software Foundation; either version 2 of the License, or
 *  (at your option) any later version.
 *
 *  This program is distributed in the hope that it will be useful,
 *  but WITHOUT ANY WARRANTY; without even the implied warranty of
 *  MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
 *  GNU General Public License for more details.
 *
 *  You should have received a copy of the GNU General Public License
 *  along with this program; if not, write to the Free Software
 *  Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
 *
 */
//#define SQUID_HELPER 1

#include "squid.h"

#if USE_ICMP

#include "Debug.h"
#include "Icmp6.h"
#include "IcmpPinger.h"
#include "leakcheck.h"
#include "SquidTime.h"

// Some system headers are only neeed internally here.
// They should not be included via the header.

#if HAVE_NETINET_IP6_H
#include <netinet/ip6.h>
#endif

// Icmp6 OP-Codes
// see http://www.iana.org/assignments/icmpv6-parameters
// NP: LowPktStr is for codes 0-127
static const char *icmp6LowPktStr[] = {
    "ICMP 0",			// 0
    "Destination Unreachable",	// 1 - RFC2463
    "Packet Too Big", 		// 2 - RFC2463
    "Time Exceeded",		// 3 - RFC2463
    "Parameter Problem",		// 4 - RFC2463
    "ICMP 5",			// 5
    "ICMP 6",			// 6
    "ICMP 7",			// 7
    "ICMP 8",			// 8
    "ICMP 9",			// 9
    "ICMP 10"			// 10
};

// NP: HighPktStr is for codes 128-255
static const char *icmp6HighPktStr[] = {
    "Echo Request",					// 128 - RFC2463
    "Echo Reply",					// 129 - RFC2463
    "Multicast Listener Query",			// 130 - RFC2710
    "Multicast Listener Report",			// 131 - RFC2710
    "Multicast Listener Done",			// 132 - RFC2710
    "Router Solicitation",				// 133 - RFC4861
    "Router Advertisement",				// 134 - RFC4861
    "Neighbor Solicitation",			// 135 - RFC4861
    "Neighbor Advertisement",			// 136 - RFC4861
    "Redirect Message",				// 137 - RFC4861
    "Router Renumbering",				// 138 - Crawford
    "ICMP Node Information Query",			// 139 - RFC4620
    "ICMP Node Information Response",		// 140 - RFC4620
    "Inverse Neighbor Discovery Solicitation",	// 141 - RFC3122
    "Inverse Neighbor Discovery Advertisement",	// 142 - RFC3122
    "Version 2 Multicast Listener Report",		// 143 - RFC3810
    "Home Agent Address Discovery Request",		// 144 - RFC3775
    "Home Agent Address Discovery Reply",		// 145 - RFC3775
    "Mobile Prefix Solicitation",			// 146 - RFC3775
    "Mobile Prefix Advertisement",			// 147 - RFC3775
    "Certification Path Solicitation",		// 148 - RFC3971
    "Certification Path Advertisement",		// 149 - RFC3971
    "ICMP Experimental (150)",			// 150 - RFC4065
    "Multicast Router Advertisement",		// 151 - RFC4286
    "Multicast Router Solicitation",		// 152 - RFC4286
    "Multicast Router Termination",			// 153 - [RFC4286]
    "ICMP 154",
    "ICMP 155",
    "ICMP 156",
    "ICMP 157",
    "ICMP 158",
    "ICMP 159",
    "ICMP 160"
};

Icmp6::Icmp6() : Icmp()
{
    ; // nothing new.
}

Icmp6::~Icmp6()
{
    Close();
}

int
Icmp6::Open(void)
{
    icmp_sock = socket(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6);

    if (icmp_sock < 0) {
        debugs(50, DBG_CRITICAL, HERE << " icmp_sock: " << xstrerror());
        return -1;
    }

    icmp_ident = getpid() & 0xffff;
    debugs(42, DBG_IMPORTANT, "pinger: ICMPv6 socket opened");

    return icmp_sock;
}

/**
 * Generates an RFC 4443 Icmp6 ECHO Packet and sends into the network.
 */
void
Icmp6::SendEcho(Ip::Address &to, int opcode, const char *payload, int len)
{
    int x;
    LOCAL_ARRAY(char, pkt, MAX_PKT6_SZ);
    struct icmp6_hdr *icmp = NULL;
    icmpEchoData *echo = NULL;
    struct addrinfo *S = NULL;
    size_t icmp6_pktsize = 0;

    memset(pkt, '\0', MAX_PKT6_SZ);
    icmp = (struct icmp6_hdr *)pkt;

    /*
     * cevans - beware signed/unsigned issues in untrusted data from
     * the network!!
     */
    if (len < 0) {
        len = 0;
    }

    // Construct Icmp6 ECHO header
    icmp->icmp6_type = ICMP6_ECHO_REQUEST;
    icmp->icmp6_code = 0;
    icmp->icmp6_cksum = 0;
    icmp->icmp6_id = icmp_ident;
    icmp->icmp6_seq = (unsigned short) icmp_pkts_sent;
    ++icmp_pkts_sent;

    icmp6_pktsize = sizeof(struct icmp6_hdr);

    // Fill Icmp6 ECHO data content
    echo = (icmpEchoData *) (pkt + sizeof(icmp6_hdr));
    echo->opcode = (unsigned char) opcode;
    memcpy(&echo->tv, &current_time, sizeof(struct timeval));

    icmp6_pktsize += sizeof(struct timeval) + sizeof(char);

    if (payload) {
        if (len > MAX_PAYLOAD)
            len = MAX_PAYLOAD;

        memcpy(echo->payload, payload, len);

        icmp6_pktsize += len;
    }

    icmp->icmp6_cksum = CheckSum((unsigned short *) icmp, icmp6_pktsize);

    to.getAddrInfo(S);
    ((sockaddr_in6*)S->ai_addr)->sin6_port = 0;

    assert(icmp6_pktsize <= MAX_PKT6_SZ);

    debugs(42, 5, HERE << "Send Icmp6 packet to " << to << ".");

    x = sendto(icmp_sock,
               (const void *) pkt,
               icmp6_pktsize,
               0,
               S->ai_addr,
               S->ai_addrlen);

    if (x < 0) {
        debugs(42, DBG_IMPORTANT, HERE << "Error sending to ICMPv6 packet to " << to << ". ERR: " << xstrerror());
    }
    debugs(42,9, HERE << "x=" << x);

    Log(to, 0, NULL, 0, 0);
    Ip::Address::FreeAddrInfo(S);
}

/**
 * Reads an RFC 4443 Icmp6 ECHO-REPLY Packet from the network.
 */
void
Icmp6::Recv(void)
{
    int n;
    struct addrinfo *from = NULL;
//    struct ip6_hdr *ip = NULL;
    static char *pkt = NULL;
    struct icmp6_hdr *icmp6header = NULL;
    icmpEchoData *echo = NULL;
    struct timeval now;
    static pingerReplyData preply;

    if (icmp_sock < 0) {
        debugs(42, DBG_CRITICAL, HERE << "dropping ICMPv6 read. No socket!?");
        return;
    }

    if (pkt == NULL) {
        pkt = (char *)xmalloc(MAX_PKT6_SZ);
    }

    Ip::Address::InitAddrInfo(from);

    n = recvfrom(icmp_sock,
                 (void *)pkt,
                 MAX_PKT6_SZ,
                 0,
                 from->ai_addr,
                 &from->ai_addrlen);

    preply.from = *from;

#if GETTIMEOFDAY_NO_TZP

    gettimeofday(&now);

#else

    gettimeofday(&now, NULL);

#endif

    debugs(42, 8, HERE << n << " bytes from " << preply.from);

// FIXME INET6 : The IPv6 Header (ip6_hdr) is not availble directly >:-(
//
// TTL still has to come from the IP header somewhere.
//	still need to strip and process it properly.
//	probably have to rely on RTT as given by timestamp in data sent and current.
    /* IPv6 Header Structures (linux)
    struct ip6_hdr

    // fields (via simple define)
    #define ip6_vfc		// N.A
    #define ip6_flow	// N/A
    #define ip6_plen	// payload length.
    #define ip6_nxt		// expect to be type 0x3a - ICMPv6
    #define ip6_hlim	// MAX hops  (always 64, but no guarantee)
    #define ip6_hops	// HOPS!!!  (can it be true??)

        ip = (struct ip6_hdr *) pkt;
        pkt += sizeof(ip6_hdr);

    debugs(42, DBG_CRITICAL, HERE << "ip6_nxt=" << ip->ip6_nxt <<
    		", ip6_plen=" << ip->ip6_plen <<
    		", ip6_hlim=" << ip->ip6_hlim <<
    		", ip6_hops=" << ip->ip6_hops	<<
    		" ::: 40 == sizef(ip6_hdr) == " << sizeof(ip6_hdr)
    );
    */

    icmp6header = (struct icmp6_hdr *) pkt;
    pkt += sizeof(icmp6_hdr);

    if (icmp6header->icmp6_type != ICMP6_ECHO_REPLY) {

        switch (icmp6header->icmp6_type) {
        case 134:
        case 135:
        case 136:
            /* ignore Router/Neighbour Advertisements */
            break;

        default:
            debugs(42, 8, HERE << preply.from << " said: " << icmp6header->icmp6_type << "/" << (int)icmp6header->icmp6_code << " " <<
                   ( icmp6header->icmp6_type&0x80 ? icmp6HighPktStr[(int)(icmp6header->icmp6_type&0x7f)] : icmp6LowPktStr[(int)(icmp6header->icmp6_type&0x7f)] )
                  );
        }
        Ip::Address::FreeAddrInfo(from);
        return;
    }

    if (icmp6header->icmp6_id != icmp_ident) {
        debugs(42, 8, HERE << "dropping Icmp6 read. IDENT check failed. ident=='" << icmp_ident << "'=='" << icmp6header->icmp6_id << "'");
        Ip::Address::FreeAddrInfo(from);
        return;
    }

    echo = (icmpEchoData *) pkt;

    preply.opcode = echo->opcode;

    struct timeval tv;
    memcpy(&tv, &echo->tv, sizeof(struct timeval));
    preply.rtt = tvSubMsec(tv, now);

    /*
     * FIXME INET6: Without access to the IPv6-Hops header we must rely on the total RTT
     *      and could caculate the hops from that, but it produces some weird value mappings using ipHops
     *	for now everything is 1 v6 hop away with variant RTT
     * WANT:    preply.hops = ip->ip6_hops; // ipHops(ip->ip_hops);
     */
    preply.hops = 1;

    preply.psize = n - /* sizeof(ip6_hdr) - */ sizeof(icmp6_hdr) - (sizeof(icmpEchoData) - MAX_PKT6_SZ);

    /* Ensure the response packet has safe payload size */
    if ( preply.psize > (unsigned short) MAX_PKT6_SZ) {
        preply.psize = MAX_PKT6_SZ;
    } else if ( preply.psize < (unsigned short)0) {
        preply.psize = 0;
    }

    Log(preply.from,
        icmp6header->icmp6_type,
        ( icmp6header->icmp6_type&0x80 ? icmp6HighPktStr[(int)(icmp6header->icmp6_type&0x7f)] : icmp6LowPktStr[(int)(icmp6header->icmp6_type&0x7f)] ),
        preply.rtt,
        preply.hops);

    /* send results of the lookup back to squid.*/
    control.SendResult(preply, (sizeof(pingerReplyData) - PINGER_PAYLOAD_SZ + preply.psize) );
    Ip::Address::FreeAddrInfo(from);
}

#endif /* USE_ICMP */
Commit	Line	Data
	1	/*
	2	* DEBUG: section 42 ICMP Pinger program
	3	* AUTHOR: Duane Wessels, Amos Jeffries
	4	*
	5	* SQUID Web Proxy Cache http://www.squid-cache.org/
	6	* ----------------------------------------------------------
	7	*
	8	* Squid is the result of efforts by numerous individuals from
	9	* the Internet community; see the CONTRIBUTORS file for full
	10	* details. Many organizations have provided support for Squid's
	11	* development; see the SPONSORS file for full details. Squid is
	12	* Copyrighted (C) 2001 by the Regents of the University of
	13	* California; see the COPYRIGHT file for full details. Squid
	14	* incorporates software developed and/or copyrighted by other
	15	* sources; see the CREDITS file for full details.
	16	*
	17	* This program is free software; you can redistribute it and/or modify
	18	* it under the terms of the GNU General Public License as published by
	19	* the Free Software Foundation; either version 2 of the License, or
	20	* (at your option) any later version.
	21	*
	22	* This program is distributed in the hope that it will be useful,
	23	* but WITHOUT ANY WARRANTY; without even the implied warranty of
	24	* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
	25	* GNU General Public License for more details.
	26	*
	27	* You should have received a copy of the GNU General Public License
	28	* along with this program; if not, write to the Free Software
	29	* Foundation, Inc., 59 Temple Place, Suite 330, Boston, MA 02111, USA.
	30	*
	31	*/
	32	//#define SQUID_HELPER 1
	33
	34	#include "squid.h"
	35
	36	#if USE_ICMP
	37
	38	#include "Debug.h"
	39	#include "Icmp6.h"
	40	#include "IcmpPinger.h"
	41	#include "leakcheck.h"
	42	#include "SquidTime.h"
	43
	44	// Some system headers are only neeed internally here.
	45	// They should not be included via the header.
	46
	47	#if HAVE_NETINET_IP6_H
	48	#include <netinet/ip6.h>
	49	#endif
	50
	51	// Icmp6 OP-Codes
	52	// see http://www.iana.org/assignments/icmpv6-parameters
	53	// NP: LowPktStr is for codes 0-127
	54	static const char *icmp6LowPktStr[] = {
	55	"ICMP 0", // 0
	56	"Destination Unreachable", // 1 - RFC2463
	57	"Packet Too Big", // 2 - RFC2463
	58	"Time Exceeded", // 3 - RFC2463
	59	"Parameter Problem", // 4 - RFC2463
	60	"ICMP 5", // 5
	61	"ICMP 6", // 6
	62	"ICMP 7", // 7
	63	"ICMP 8", // 8
	64	"ICMP 9", // 9
	65	"ICMP 10" // 10
	66	};
	67
	68	// NP: HighPktStr is for codes 128-255
	69	static const char *icmp6HighPktStr[] = {
	70	"Echo Request", // 128 - RFC2463
	71	"Echo Reply", // 129 - RFC2463
	72	"Multicast Listener Query", // 130 - RFC2710
	73	"Multicast Listener Report", // 131 - RFC2710
	74	"Multicast Listener Done", // 132 - RFC2710
	75	"Router Solicitation", // 133 - RFC4861
	76	"Router Advertisement", // 134 - RFC4861
	77	"Neighbor Solicitation", // 135 - RFC4861
	78	"Neighbor Advertisement", // 136 - RFC4861
	79	"Redirect Message", // 137 - RFC4861
	80	"Router Renumbering", // 138 - Crawford
	81	"ICMP Node Information Query", // 139 - RFC4620
	82	"ICMP Node Information Response", // 140 - RFC4620
	83	"Inverse Neighbor Discovery Solicitation", // 141 - RFC3122
	84	"Inverse Neighbor Discovery Advertisement", // 142 - RFC3122
	85	"Version 2 Multicast Listener Report", // 143 - RFC3810
	86	"Home Agent Address Discovery Request", // 144 - RFC3775
	87	"Home Agent Address Discovery Reply", // 145 - RFC3775
	88	"Mobile Prefix Solicitation", // 146 - RFC3775
	89	"Mobile Prefix Advertisement", // 147 - RFC3775
	90	"Certification Path Solicitation", // 148 - RFC3971
	91	"Certification Path Advertisement", // 149 - RFC3971
	92	"ICMP Experimental (150)", // 150 - RFC4065
	93	"Multicast Router Advertisement", // 151 - RFC4286
	94	"Multicast Router Solicitation", // 152 - RFC4286
	95	"Multicast Router Termination", // 153 - [RFC4286]
	96	"ICMP 154",
	97	"ICMP 155",
	98	"ICMP 156",
	99	"ICMP 157",
	100	"ICMP 158",
	101	"ICMP 159",
	102	"ICMP 160"
	103	};
	104
	105	Icmp6::Icmp6() : Icmp()
	106	{
	107	; // nothing new.
	108	}
	109
	110	Icmp6::~Icmp6()
	111	{
	112	Close();
	113	}
	114
	115	int
	116	Icmp6::Open(void)
	117	{
	118	icmp_sock = socket(PF_INET6, SOCK_RAW, IPPROTO_ICMPV6);
	119
	120	if (icmp_sock < 0) {
	121	debugs(50, DBG_CRITICAL, HERE << " icmp_sock: " << xstrerror());
	122	return -1;
	123	}
	124
	125	icmp_ident = getpid() & 0xffff;
	126	debugs(42, DBG_IMPORTANT, "pinger: ICMPv6 socket opened");
	127
	128	return icmp_sock;
	129	}
	130
	131	/**
	132	* Generates an RFC 4443 Icmp6 ECHO Packet and sends into the network.
	133	*/
	134	void
	135	Icmp6::SendEcho(Ip::Address &to, int opcode, const char *payload, int len)
	136	{
	137	int x;
	138	LOCAL_ARRAY(char, pkt, MAX_PKT6_SZ);
	139	struct icmp6_hdr *icmp = NULL;
	140	icmpEchoData *echo = NULL;
	141	struct addrinfo *S = NULL;
	142	size_t icmp6_pktsize = 0;
	143
	144	memset(pkt, '\0', MAX_PKT6_SZ);
	145	icmp = (struct icmp6_hdr *)pkt;
	146
	147	/*
	148	* cevans - beware signed/unsigned issues in untrusted data from
	149	* the network!!
	150	*/
	151	if (len < 0) {
	152	len = 0;
	153	}
	154
	155	// Construct Icmp6 ECHO header
	156	icmp->icmp6_type = ICMP6_ECHO_REQUEST;
	157	icmp->icmp6_code = 0;
	158	icmp->icmp6_cksum = 0;
	159	icmp->icmp6_id = icmp_ident;
	160	icmp->icmp6_seq = (unsigned short) icmp_pkts_sent;
	161	++icmp_pkts_sent;
	162
	163	icmp6_pktsize = sizeof(struct icmp6_hdr);
	164
	165	// Fill Icmp6 ECHO data content
	166	echo = (icmpEchoData *) (pkt + sizeof(icmp6_hdr));
	167	echo->opcode = (unsigned char) opcode;
	168	memcpy(&echo->tv, &current_time, sizeof(struct timeval));
	169
	170	icmp6_pktsize += sizeof(struct timeval) + sizeof(char);
	171
	172	if (payload) {
	173	if (len > MAX_PAYLOAD)
	174	len = MAX_PAYLOAD;
	175
	176	memcpy(echo->payload, payload, len);
	177
	178	icmp6_pktsize += len;
	179	}
	180
	181	icmp->icmp6_cksum = CheckSum((unsigned short *) icmp, icmp6_pktsize);
	182
	183	to.getAddrInfo(S);
	184	((sockaddr_in6*)S->ai_addr)->sin6_port = 0;
	185
	186	assert(icmp6_pktsize <= MAX_PKT6_SZ);
	187
	188	debugs(42, 5, HERE << "Send Icmp6 packet to " << to << ".");
	189
	190	x = sendto(icmp_sock,
	191	(const void *) pkt,
	192	icmp6_pktsize,
	193	0,
	194	S->ai_addr,
	195	S->ai_addrlen);
	196
	197	if (x < 0) {
	198	debugs(42, DBG_IMPORTANT, HERE << "Error sending to ICMPv6 packet to " << to << ". ERR: " << xstrerror());
	199	}
	200	debugs(42,9, HERE << "x=" << x);
	201
	202	Log(to, 0, NULL, 0, 0);
	203	Ip::Address::FreeAddrInfo(S);
	204	}
	205
	206	/**
	207	* Reads an RFC 4443 Icmp6 ECHO-REPLY Packet from the network.
	208	*/
	209	void
	210	Icmp6::Recv(void)
	211	{
	212	int n;
	213	struct addrinfo *from = NULL;
	214	// struct ip6_hdr *ip = NULL;
	215	static char *pkt = NULL;
	216	struct icmp6_hdr *icmp6header = NULL;
	217	icmpEchoData *echo = NULL;
	218	struct timeval now;
	219	static pingerReplyData preply;
	220
	221	if (icmp_sock < 0) {
	222	debugs(42, DBG_CRITICAL, HERE << "dropping ICMPv6 read. No socket!?");
	223	return;
	224	}
	225
	226	if (pkt == NULL) {
	227	pkt = (char *)xmalloc(MAX_PKT6_SZ);
	228	}
	229
	230	Ip::Address::InitAddrInfo(from);
	231
	232	n = recvfrom(icmp_sock,
	233	(void *)pkt,
	234	MAX_PKT6_SZ,
	235	0,
	236	from->ai_addr,
	237	&from->ai_addrlen);
	238
	239	preply.from = *from;
	240
	241	#if GETTIMEOFDAY_NO_TZP
	242
	243	gettimeofday(&now);
	244
	245	#else
	246
	247	gettimeofday(&now, NULL);
	248
	249	#endif
	250
	251	debugs(42, 8, HERE << n << " bytes from " << preply.from);
	252
	253	// FIXME INET6 : The IPv6 Header (ip6_hdr) is not availble directly >:-(
	254	//
	255	// TTL still has to come from the IP header somewhere.
	256	// still need to strip and process it properly.
	257	// probably have to rely on RTT as given by timestamp in data sent and current.
	258	/* IPv6 Header Structures (linux)
	259	struct ip6_hdr
	260
	261	// fields (via simple define)
	262	#define ip6_vfc // N.A
	263	#define ip6_flow // N/A
	264	#define ip6_plen // payload length.
	265	#define ip6_nxt // expect to be type 0x3a - ICMPv6
	266	#define ip6_hlim // MAX hops (always 64, but no guarantee)
	267	#define ip6_hops // HOPS!!! (can it be true??)
	268
	269	ip = (struct ip6_hdr *) pkt;
	270	pkt += sizeof(ip6_hdr);
	271
	272	debugs(42, DBG_CRITICAL, HERE << "ip6_nxt=" << ip->ip6_nxt <<
	273	", ip6_plen=" << ip->ip6_plen <<
	274	", ip6_hlim=" << ip->ip6_hlim <<
	275	", ip6_hops=" << ip->ip6_hops <<
	276	" ::: 40 == sizef(ip6_hdr) == " << sizeof(ip6_hdr)
	277	);
	278	*/
	279
	280	icmp6header = (struct icmp6_hdr *) pkt;
	281	pkt += sizeof(icmp6_hdr);
	282
	283	if (icmp6header->icmp6_type != ICMP6_ECHO_REPLY) {
	284
	285	switch (icmp6header->icmp6_type) {
	286	case 134:
	287	case 135:
	288	case 136:
	289	/* ignore Router/Neighbour Advertisements */
	290	break;
	291
	292	default:
	293	debugs(42, 8, HERE << preply.from << " said: " << icmp6header->icmp6_type << "/" << (int)icmp6header->icmp6_code << " " <<
	294	( icmp6header->icmp6_type&0x80 ? icmp6HighPktStr[(int)(icmp6header->icmp6_type&0x7f)] : icmp6LowPktStr[(int)(icmp6header->icmp6_type&0x7f)] )
	295	);
	296	}
	297	Ip::Address::FreeAddrInfo(from);
	298	return;
	299	}
	300
	301	if (icmp6header->icmp6_id != icmp_ident) {
	302	debugs(42, 8, HERE << "dropping Icmp6 read. IDENT check failed. ident=='" << icmp_ident << "'=='" << icmp6header->icmp6_id << "'");
	303	Ip::Address::FreeAddrInfo(from);
	304	return;
	305	}
	306
	307	echo = (icmpEchoData *) pkt;
	308
	309	preply.opcode = echo->opcode;
	310
	311	struct timeval tv;
	312	memcpy(&tv, &echo->tv, sizeof(struct timeval));
	313	preply.rtt = tvSubMsec(tv, now);
	314
	315	/*
	316	* FIXME INET6: Without access to the IPv6-Hops header we must rely on the total RTT
	317	* and could caculate the hops from that, but it produces some weird value mappings using ipHops
	318	* for now everything is 1 v6 hop away with variant RTT
	319	* WANT: preply.hops = ip->ip6_hops; // ipHops(ip->ip_hops);
	320	*/
	321	preply.hops = 1;
	322
	323	preply.psize = n - /* sizeof(ip6_hdr) - */ sizeof(icmp6_hdr) - (sizeof(icmpEchoData) - MAX_PKT6_SZ);
	324
	325	/* Ensure the response packet has safe payload size */
	326	if ( preply.psize > (unsigned short) MAX_PKT6_SZ) {
	327	preply.psize = MAX_PKT6_SZ;
	328	} else if ( preply.psize < (unsigned short)0) {
	329	preply.psize = 0;
	330	}
	331
	332	Log(preply.from,
	333	icmp6header->icmp6_type,
	334	( icmp6header->icmp6_type&0x80 ? icmp6HighPktStr[(int)(icmp6header->icmp6_type&0x7f)] : icmp6LowPktStr[(int)(icmp6header->icmp6_type&0x7f)] ),
	335	preply.rtt,
	336	preply.hops);
	337
	338	/* send results of the lookup back to squid.*/
	339	control.SendResult(preply, (sizeof(pingerReplyData) - PINGER_PAYLOAD_SZ + preply.psize) );
	340	Ip::Address::FreeAddrInfo(from);
	341	}
	342
	343	#endif /* USE_ICMP */