On Tue, Oct 29, 2019 at 3:29 PM Lorenzo Bianconi <lorenzo.bianc...@redhat.com> wrote: > > Introduce the possibility to specify a DNSSL option to Router > Advertisement packets. DNS Search list can be specified using > 'dnssl' tag in the ipv6_ra_configs column of logical router > port table > > Signed-off-by: Lorenzo Bianconi <lorenzo.bianc...@redhat.com> > --- > Changes since v4: > - update documentation > - fix possible array out of bounds issue in packet_put_ra_dnssl_opt > - fix strtok_r usage > --- > controller/pinctrl.c | 59 ++++++++++++++++++++++++++++++++++++++++++++ > lib/ovn-l7.h | 11 +++++++++ > northd/ovn-northd.c | 4 +++ > ovn-nb.xml | 5 ++++ > tests/ovn.at | 30 ++++++++++++++-------- > 5 files changed, 99 insertions(+), 10 deletions(-) > > diff --git a/controller/pinctrl.c b/controller/pinctrl.c > index f105ebb5c..cddf98648 100644 > --- a/controller/pinctrl.c > +++ b/controller/pinctrl.c > @@ -2194,6 +2194,7 @@ struct ipv6_ra_config { > struct lport_addresses prefixes; > struct in6_addr rdnss; > bool has_rdnss; > + struct ds dnssl; > }; > > struct ipv6_ra_state { > @@ -2215,6 +2216,7 @@ ipv6_ra_config_delete(struct ipv6_ra_config *config) > { > if (config) { > destroy_lport_addresses(&config->prefixes); > + ds_destroy(&config->dnssl); > free(config); > } > } > @@ -2253,6 +2255,7 @@ ipv6_ra_update_config(const struct sbrec_port_binding > *pb) > nd_ra_min_interval_default(config->max_interval)); > config->mtu = smap_get_int(&pb->options, "ipv6_ra_mtu", ND_MTU_DEFAULT); > config->la_flags = IPV6_ND_RA_OPT_PREFIX_ON_LINK; > + ds_init(&config->dnssl); > > const char *address_mode = smap_get(&pb->options, > "ipv6_ra_address_mode"); > if (!address_mode) { > @@ -2298,6 +2301,11 @@ ipv6_ra_update_config(const struct sbrec_port_binding > *pb) > } > config->has_rdnss = !!rdnss; > > + const char *dnssl = smap_get(&pb->options, "ipv6_ra_dnssl"); > + if (dnssl) { > + ds_put_buffer(&config->dnssl, dnssl, strlen(dnssl)); > + } > + > return config; > > fail: > @@ -2354,6 +2362,53 @@ packet_put_ra_rdnss_opt(struct dp_packet *b, uint8_t > num, > prev_l4_size + len * > 8)); > } > > +static void > +packet_put_ra_dnssl_opt(struct dp_packet *b, ovs_be32 lifetime, > + char *dnssl_list) > +{ > + size_t prev_l4_size = dp_packet_l4_size(b); > + size_t size = sizeof(struct ovs_nd_dnssl); > + struct ip6_hdr *nh = dp_packet_l3(b); > + char *t0, *r0, dnssl[255] = {}; > + int i = 0; > + > + /* Multiple DNS Search List must be 'comma' separated > + * (e.g. "a.b.c, d.e.f") */
Can you please add a comment on how the dns list will be encode with an example. Like if dns list is a.b.c,www.ovn.org then it will be encoded as - 01 61 01 62 01 63 00 03 77 77 77 03 6f 76 63 03 6f 72 67 00 This will really help in understanding what's going on. Also can you link the RFC version. > + for (t0 = strtok_r(dnssl_list, ",", &r0); t0; > + t0 = strtok_r(NULL, ",", &r0)) { > + char *t1, *r1; > + > + size += strlen(t0) + 2; > + if (size > sizeof(dnssl)) { For the sake of simplicity let's assume the length of dnssl is 10. Then if the dns list is a.b.c,d.e.f then this will cause the buffer to overflow right ? For the first outer for loop with t0 = a.b.c, the 'size' will be 7. So 7 < 10. In the next outer for loop with t0 = d.e.f, the size will be again 7 and it will cause the inner for loop to copy the contents beyond the size of dnssl right ? I think this code needs to be refined a bit to take all these things into consideration. Thanks Numan > + return; > + } > + > + for (t1 = strtok_r(t0, ".", &r1); t1; > + t1 = strtok_r(NULL, ".", &r1)) { > + dnssl[i++] = strlen(t1); > + memcpy(&dnssl[i], t1, strlen(t1)); > + i += strlen(t1); > + } > + dnssl[i++] = 0; > + } > + size = ROUND_UP(size, 8); > + nh->ip6_plen = htons(prev_l4_size + size); > + > + struct ovs_nd_dnssl *nd_dnssl = dp_packet_put_uninit(b, sizeof > *nd_dnssl); > + nd_dnssl->type = ND_OPT_DNSSL; > + nd_dnssl->len = size / 8; > + nd_dnssl->reserved = 0; > + put_16aligned_be32(&nd_dnssl->lifetime, lifetime); > + > + dp_packet_put(b, dnssl, size - sizeof *nd_dnssl); > + > + struct ovs_ra_msg *ra = dp_packet_l4(b); > + ra->icmph.icmp6_cksum = 0; > + uint32_t icmp_csum = packet_csum_pseudoheader6(dp_packet_l3(b)); > + ra->icmph.icmp6_cksum = csum_finish(csum_continue(icmp_csum, ra, > + prev_l4_size + size)); > +} > + > /* Called with in the pinctrl_handler thread context. */ > static long long int > ipv6_ra_send(struct rconn *swconn, struct ipv6_ra_state *ra) > @@ -2382,6 +2437,10 @@ ipv6_ra_send(struct rconn *swconn, struct > ipv6_ra_state *ra) > packet_put_ra_rdnss_opt(&packet, 1, htonl(0xffffffff), > &ra->config->rdnss); > } > + if (ra->config->dnssl.length) { > + packet_put_ra_dnssl_opt(&packet, htonl(0xffffffff), > + ra->config->dnssl.string); > + } > > uint64_t ofpacts_stub[4096 / 8]; > struct ofpbuf ofpacts = OFPBUF_STUB_INITIALIZER(ofpacts_stub); > diff --git a/lib/ovn-l7.h b/lib/ovn-l7.h > index 12cee6329..5fc370bf5 100644 > --- a/lib/ovn-l7.h > +++ b/lib/ovn-l7.h > @@ -231,6 +231,17 @@ struct nd_rdnss_opt { > }; > BUILD_ASSERT_DECL(ND_RDNSS_OPT_LEN == sizeof(struct nd_rdnss_opt)); > > +/* DNSSL option RFC 6106 */ > +#define ND_OPT_DNSSL 31 > +#define ND_DNSSL_OPT_LEN 8 > +struct ovs_nd_dnssl { > + u_int8_t type; /* ND_OPT_DNSSL */ > + u_int8_t len; /* >= 2 */ > + ovs_be16 reserved; > + ovs_16aligned_be32 lifetime; > +}; > +BUILD_ASSERT_DECL(ND_DNSSL_OPT_LEN == sizeof(struct ovs_nd_dnssl)); > + > #define DHCPV6_DUID_LL 3 > #define DHCPV6_HW_TYPE_ETH 1 > > diff --git a/northd/ovn-northd.c b/northd/ovn-northd.c > index 33fe9363c..194e4bf4a 100644 > --- a/northd/ovn-northd.c > +++ b/northd/ovn-northd.c > @@ -6489,6 +6489,10 @@ copy_ra_to_sb(struct ovn_port *op, const char > *address_mode) > if (rdnss) { > smap_add(&options, "ipv6_ra_rdnss", rdnss); > } > + const char *dnssl = smap_get(&op->nbrp->ipv6_ra_configs, "dnssl"); > + if (dnssl) { > + smap_add(&options, "ipv6_ra_dnssl", dnssl); > + } > > smap_add(&options, "ipv6_ra_src_eth", op->lrp_networks.ea_s); > > diff --git a/ovn-nb.xml b/ovn-nb.xml > index 2faf9390b..899089422 100644 > --- a/ovn-nb.xml > +++ b/ovn-nb.xml > @@ -1890,6 +1890,11 @@ > IPv6 address of RDNSS server announced in RA packets. At the moment > OVN supports just one RDNSS server. > </column> > + > + <column name="ipv6_ra_configs" key="dnssl"> > + DNS Search List announced in RA packets. Multiple DNS Search List > + must be 'comma' separated (e.g. "a.b.c, d.e.f") > + </column> > </group> > > <group title="Options"> > diff --git a/tests/ovn.at b/tests/ovn.at > index 1cfc0796d..9f06059fa 100644 > --- a/tests/ovn.at > +++ b/tests/ovn.at > @@ -11408,14 +11408,15 @@ construct_expected_ra() { > local mtu=$1 > local ra_mo=$2 > local rdnss=$3 > - local ra_prefix_la=$4 > + local dnssl=$4 > + local ra_prefix_la=$5 > > local slla=0101${src_mac} > local mtu_opt="" > if test $mtu != 0; then > mtu_opt=05010000${mtu} > fi > - shift 4 > + shift 5 > > local prefix="" > while [[ $# -gt 0 ]] ; do > @@ -11429,8 +11430,12 @@ construct_expected_ra() { > if test $rdnss != 0; then > rdnss_opt=19030000ffffffff${rdnss} > fi > + local dnssl_opt="" > + if test $dnssl != 0; then > + dnssl_opt=1f030000ffffffff${dnssl} > + fi > > - local > ra=ff${ra_mo}ffff0000000000000000${slla}${mtu_opt}${prefix}${rdnss_opt} > + local > ra=ff${ra_mo}ffff0000000000000000${slla}${mtu_opt}${prefix}${rdnss_opt}${dnssl_opt} > local icmp=8600XXXX${ra} > > local ip_len=$(expr ${#icmp} / 2) > @@ -11465,28 +11470,33 @@ ra_test() { > } > > # Baseline test with no MTU > -ra_test 0 00 0 c0 40 aef00000000000000000000000000000 > +ra_test 0 00 0 0 c0 40 aef00000000000000000000000000000 > > # Now make sure an MTU option makes it > ovn-nbctl --wait=hv set Logical_Router_Port ro-sw ipv6_ra_configs:mtu=1500 > -ra_test 000005dc 00 0 c0 40 aef00000000000000000000000000000 > +ra_test 000005dc 00 0 0 c0 40 aef00000000000000000000000000000 > > # Now test for multiple network prefixes > ovn-nbctl --wait=hv set Logical_Router_port ro-sw networks='aef0\:\:1/64 > fd0f\:\:1/48' > -ra_test 000005dc 00 0 c0 40 aef00000000000000000000000000000 30 > fd0f0000000000000000000000000000 > +ra_test 000005dc 00 0 0 c0 40 aef00000000000000000000000000000 30 > fd0f0000000000000000000000000000 > > # Now test for RDNSS > ovn-nbctl --wait=hv set Logical_Router_port ro-sw > ipv6_ra_configs:rdnss='aef0::11' > dns_addr=aef00000000000000000000000000011 > -ra_test 000005dc 00 $dns_addr c0 40 aef00000000000000000000000000000 30 > fd0f0000000000000000000000000000 > +ra_test 000005dc 00 $dns_addr 0 c0 40 aef00000000000000000000000000000 30 > fd0f0000000000000000000000000000 > + > +# Now test for DNSSL > +ovn-nbctl --wait=hv set Logical_Router_port ro-sw > ipv6_ra_configs:dnssl="aa.bb.cc" > +dnssl=02616102626202636300000000000000 > +ra_test 000005dc 00 $dns_addr $dnssl c0 40 aef00000000000000000000000000000 > 30 fd0f0000000000000000000000000000 > > -# Test a different address mode now > +## Test a different address mode now > ovn-nbctl --wait=hv set Logical_Router_Port ro-sw > ipv6_ra_configs:address_mode=dhcpv6_stateful > -ra_test 000005dc 80 $dns_addr 80 40 aef00000000000000000000000000000 30 > fd0f0000000000000000000000000000 > +ra_test 000005dc 80 $dns_addr $dnssl 80 40 aef00000000000000000000000000000 > 30 fd0f0000000000000000000000000000 > > # And the other address mode > ovn-nbctl --wait=hv set Logical_Router_Port ro-sw > ipv6_ra_configs:address_mode=dhcpv6_stateless > -ra_test 000005dc 40 $dns_addr c0 40 aef00000000000000000000000000000 30 > fd0f0000000000000000000000000000 > +ra_test 000005dc 40 $dns_addr $dnssl c0 40 aef00000000000000000000000000000 > 30 fd0f0000000000000000000000000000 > > OVN_CLEANUP([hv1],[hv2]) > AT_CLEANUP > -- > 2.21.0 > > _______________________________________________ > dev mailing list > d...@openvswitch.org > https://mail.openvswitch.org/mailman/listinfo/ovs-dev _______________________________________________ dev mailing list d...@openvswitch.org https://mail.openvswitch.org/mailman/listinfo/ovs-dev