Commit e42f869b authored by Samuel Thibault's avatar Samuel Thibault
Browse files

slirp: Make RA build more flexible 



Do not hardcode the RA size at all, use a pl_size variable which
accounts the accumulated size, and fill rip->ip_pl at the end.

This will allow to make some blocks optional.

Signed-off-by: default avatarSamuel Thibault <samuel.thibault@ens-lyon.org>
Reviewed-by: default avatarPhilippe Mathieu-Daudé <f4bug@amsat.org>
parent 51149a2a

slirp/ip6_icmp.c

+9 −15
Original line number Diff line number Diff line
@@ -143,17 +143,10 @@ void ndp_send_ra(Slirp *slirp) 
    /* Build IPv6 packet */

    struct mbuf *t = m_get(slirp);

    struct ip6 *rip = mtod(t, struct ip6 *);

    size_t pl_size = 0;

    rip->ip_src = (struct in6_addr)LINKLOCAL_ADDR;

    rip->ip_dst = (struct in6_addr)ALLNODES_MULTICAST;

    rip->ip_nh = IPPROTO_ICMPV6;

    rip->ip_pl = htons(ICMP6_NDP_RA_MINLEN

                        + NDPOPT_LINKLAYER_LEN

                        + NDPOPT_PREFIXINFO_LEN

#ifndef _WIN32

                        + NDPOPT_RDNSS_LEN

#endif

                        );

    t->m_len = sizeof(struct ip6) + ntohs(rip->ip_pl);



    /* Build ICMPv6 packet */

    t->m_data += sizeof(struct ip6);
@@ -171,6 +164,7 @@ void ndp_send_ra(Slirp *slirp) 
    ricmp->icmp6_nra.reach_time = htonl(NDP_AdvReachableTime);

    ricmp->icmp6_nra.retrans_time = htonl(NDP_AdvRetransTime);

    t->m_data += ICMP6_NDP_RA_MINLEN;

    pl_size += ICMP6_NDP_RA_MINLEN;



    /* Source link-layer address (NDP option) */

    struct ndpopt *opt = mtod(t, struct ndpopt *);
@@ -178,6 +172,7 @@ void ndp_send_ra(Slirp *slirp) 
    opt->ndpopt_len = NDPOPT_LINKLAYER_LEN / 8;

    in6_compute_ethaddr(rip->ip_src, opt->ndpopt_linklayer);

    t->m_data += NDPOPT_LINKLAYER_LEN;

    pl_size += NDPOPT_LINKLAYER_LEN;



    /* Prefix information (NDP option) */

    struct ndpopt *opt2 = mtod(t, struct ndpopt *);
@@ -192,6 +187,7 @@ void ndp_send_ra(Slirp *slirp) 
    opt2->ndpopt_prefixinfo.reserved2 = 0;

    opt2->ndpopt_prefixinfo.prefix = slirp->vprefix_addr6;

    t->m_data += NDPOPT_PREFIXINFO_LEN;

    pl_size += NDPOPT_PREFIXINFO_LEN;



#ifndef _WIN32

    /* Prefix information (NDP option) */
@@ -203,16 +199,14 @@ void ndp_send_ra(Slirp *slirp) 
    opt3->ndpopt_rdnss.lifetime = htonl(2 * NDP_MaxRtrAdvInterval);

    opt3->ndpopt_rdnss.addr = slirp->vnameserver_addr6;

    t->m_data += NDPOPT_RDNSS_LEN;

    pl_size += NDPOPT_RDNSS_LEN;

#endif



    rip->ip_pl = htons(pl_size);

    t->m_data -= sizeof(struct ip6) + pl_size;

    t->m_len = sizeof(struct ip6) + pl_size;



    /* ICMPv6 Checksum */

#ifndef _WIN32

    t->m_data -= NDPOPT_RDNSS_LEN;

#endif

    t->m_data -= NDPOPT_PREFIXINFO_LEN;

    t->m_data -= NDPOPT_LINKLAYER_LEN;

    t->m_data -= ICMP6_NDP_RA_MINLEN;

    t->m_data -= sizeof(struct ip6);

    ricmp->icmp6_cksum = ip6_cksum(t);



    ip6_output(NULL, t, 0);