With this clients can learn the presence and used prefix for Network
Address and Protocol Translation between IPv6 and IPv4 (NAT64).
Apparently there is support in mobile devices as well as in macOS.
This option, together with the the dhcp "IPv6-only preferred"
option (108) enables the Customer-side transLATor (CLAT) on macOS so
IPv4 literals can be used in IPv6-only networks.
OK?
diff --git engine.c engine.c
index dddff2d4579..543abffe388 100644
--- engine.c
+++ engine.c
@@ -269,6 +269,7 @@ engine_dispatch_main(int fd, short event, void *bula)
struct ra_prefix_conf *ra_prefix_conf;
struct ra_rdnss_conf *ra_rdnss_conf;
struct ra_dnssl_conf *ra_dnssl_conf;
+ struct ra_pref64_conf *pref64;
ssize_t n;
int shut = 0;
@@ -333,6 +334,7 @@ engine_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INIT(&nconf->ra_iface_list);
SIMPLEQ_INIT(&nconf->ra_options.ra_rdnss_list);
SIMPLEQ_INIT(&nconf->ra_options.ra_dnssl_list);
+ SIMPLEQ_INIT(&nconf->ra_options.ra_pref64_list);
ra_options = &nconf->ra_options;
break;
case IMSG_RECONF_RA_IFACE:
@@ -349,6 +351,7 @@ engine_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INIT(&ra_iface_conf->ra_prefix_list);
SIMPLEQ_INIT(&ra_iface_conf->ra_options.ra_rdnss_list);
SIMPLEQ_INIT(&ra_iface_conf->ra_options.ra_dnssl_list);
+ SIMPLEQ_INIT(&ra_iface_conf->ra_options.ra_pref64_list);
SIMPLEQ_INSERT_TAIL(&nconf->ra_iface_list,
ra_iface_conf, entry);
ra_options = &ra_iface_conf->ra_options;
@@ -405,6 +408,18 @@ engine_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INSERT_TAIL(&ra_options->ra_dnssl_list,
ra_dnssl_conf, entry);
break;
+ case IMSG_RECONF_RA_PREF64:
+ if(IMSG_DATA_SIZE(imsg) != sizeof(struct
+ ra_pref64_conf))
+ fatalx("%s: IMSG_RECONF_RA_PREF64 wrong length:
"
+ "%lu", __func__, IMSG_DATA_SIZE(imsg));
+ if ((pref64 = malloc(sizeof(struct ra_pref64_conf))) ==
+ NULL)
+ fatal(NULL);
+ memcpy(pref64, imsg.data, sizeof(struct
ra_pref64_conf));
+ SIMPLEQ_INSERT_TAIL(&ra_options->ra_pref64_list, pref64,
+ entry);
+ break;
case IMSG_RECONF_END:
if (nconf == NULL)
fatalx("%s: IMSG_RECONF_END without "
diff --git frontend.c frontend.c
index 30bcde218c4..435d6aed8a8 100644
--- frontend.c
+++ frontend.c
@@ -113,6 +113,14 @@ struct ra_iface {
uint8_t data[RA_MAX_SIZE];
};
+#define ND_OPT_PREF64 38
+struct nd_opt_pref64 {
+ u_int8_t nd_opt_pref64_type;
+ u_int8_t nd_opt_pref64_len;
+ u_int16_t nd_opt_pref64_sltime_plc;
+ u_int8_t nd_opt_pref64[12];
+};
+
TAILQ_HEAD(, ra_iface) ra_interfaces;
__dead void frontend_shutdown(void);
@@ -300,6 +308,7 @@ frontend_dispatch_main(int fd, short event, void *bula)
struct ra_prefix_conf *ra_prefix_conf;
struct ra_rdnss_conf *ra_rdnss_conf;
struct ra_dnssl_conf *ra_dnssl_conf;
+ struct ra_pref64_conf *pref64;
int n, shut = 0, icmp6sock, rdomain;
if (event & EV_READ) {
@@ -361,6 +370,7 @@ frontend_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INIT(&nconf->ra_iface_list);
SIMPLEQ_INIT(&nconf->ra_options.ra_rdnss_list);
SIMPLEQ_INIT(&nconf->ra_options.ra_dnssl_list);
+ SIMPLEQ_INIT(&nconf->ra_options.ra_pref64_list);
ra_options = &nconf->ra_options;
break;
case IMSG_RECONF_RA_IFACE:
@@ -377,6 +387,7 @@ frontend_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INIT(&ra_iface_conf->ra_prefix_list);
SIMPLEQ_INIT(&ra_iface_conf->ra_options.ra_rdnss_list);
SIMPLEQ_INIT(&ra_iface_conf->ra_options.ra_dnssl_list);
+ SIMPLEQ_INIT(&ra_iface_conf->ra_options.ra_pref64_list);
SIMPLEQ_INSERT_TAIL(&nconf->ra_iface_list,
ra_iface_conf, entry);
ra_options = &ra_iface_conf->ra_options;
@@ -433,6 +444,18 @@ frontend_dispatch_main(int fd, short event, void *bula)
SIMPLEQ_INSERT_TAIL(&ra_options->ra_dnssl_list,
ra_dnssl_conf, entry);
break;
+ case IMSG_RECONF_RA_PREF64:
+ if (IMSG_DATA_SIZE(imsg) != sizeof(struct
+ ra_pref64_conf))
+ fatalx("%s: IMSG_RECONF_RA_PREF64 wrong length:
"
+ "%lu", __func__, IMSG_DATA_SIZE(imsg));
+ if ((pref64 = malloc(sizeof(struct ra_pref64_conf))) ==
+ NULL)
+ fatal(NULL);
+ memcpy(pref64, imsg.data, sizeof(struct
ra_pref64_conf));
+ SIMPLEQ_INSERT_TAIL(&ra_options->ra_pref64_list, pref64,
+ entry);
+ break;
case IMSG_RECONF_END:
if (nconf == NULL)
fatalx("%s: IMSG_RECONF_END without "
@@ -1084,8 +1107,10 @@ build_packet(struct ra_iface *ra_iface)
struct ra_prefix_conf *ra_prefix_conf;
struct nd_opt_rdnss *ndopt_rdnss;
struct nd_opt_dnssl *ndopt_dnssl;
+ struct nd_opt_pref64 *ndopt_pref64;
struct ra_rdnss_conf *ra_rdnss;
struct ra_dnssl_conf *ra_dnssl;
+ struct ra_pref64_conf *pref64;
size_t len, label_len;
uint8_t *p, buf[RA_MAX_SIZE];
char *label_start, *label_end;
@@ -1108,6 +1133,10 @@ build_packet(struct ra_iface *ra_iface)
len += sizeof(*ndopt_dnssl) +
((ra_iface_conf->ra_options.dnssl_len + 7) & ~7);
+ SIMPLEQ_FOREACH(pref64, &ra_iface_conf->ra_options.ra_pref64_list,
+ entry)
+ len += sizeof(struct nd_opt_pref64);
+
if (len > sizeof(ra_iface->data))
fatalx("%s: packet too big", __func__); /* XXX send multiple */
@@ -1207,6 +1236,46 @@ build_packet(struct ra_iface *ra_iface)
*p++ = '\0';
}
+ SIMPLEQ_FOREACH(pref64, &ra_iface_conf->ra_options.ra_pref64_list,
+ entry) {
+ uint16_t sltime_plc;
+
+ /* scaled lifetime in units of 8 seconds */
+ sltime_plc = pref64->ltime / 8;
+ sltime_plc = sltime_plc << 3;
+ /* encode prefix lenght in lower 3 bits */
+ switch (pref64->prefixlen) {
+ case 96:
+ sltime_plc |= 0;
+ break;
+ case 64:
+ sltime_plc |= 1;
+ break;
+ case 56:
+ sltime_plc |= 2;
+ break;
+ case 48:
+ sltime_plc |= 3;
+ break;
+ case 40:
+ sltime_plc |= 4;
+ break;
+ case 32:
+ sltime_plc |= 5;
+ break;
+ default:
+ fatalx("%s: invalid pref64 length: %d", __func__,
+ pref64->prefixlen);
+ }
+ ndopt_pref64 = (struct nd_opt_pref64 *)p;
+ ndopt_pref64->nd_opt_pref64_type = ND_OPT_PREF64;
+ ndopt_pref64->nd_opt_pref64_len = 2;
+ ndopt_pref64->nd_opt_pref64_sltime_plc = htons(sltime_plc);
+ memcpy(ndopt_pref64->nd_opt_pref64, &pref64->prefix,
+ sizeof(ndopt_pref64->nd_opt_pref64));
+ p += sizeof(struct nd_opt_pref64);
+ }
+
if (len != ra_iface->datalen || memcmp(buf, ra_iface->data, len)
!= 0) {
memcpy(ra_iface->data, buf, len);
diff --git parse.y parse.y
index 41b1f0da133..070cab3099c 100644
--- parse.y
+++ parse.y
@@ -96,11 +96,15 @@ static int errors;
static struct ra_iface_conf *ra_iface_conf;
static struct ra_prefix_conf *ra_prefix_conf;
+static struct ra_pref64_conf *ra_pref64_conf;
struct ra_prefix_conf *conf_get_ra_prefix(struct in6_addr*, int);
+struct ra_pref64_conf *conf_get_ra_pref64(struct in6_addr*, int);
struct ra_iface_conf *conf_get_ra_iface(char *);
void copy_dns_options(const struct ra_options_conf *,
struct ra_options_conf *);
+void copy_pref64_options(const struct ra_options_conf *,
+ struct ra_options_conf *);
typedef struct {
union {
@@ -116,7 +120,7 @@ typedef struct {
%token DEFAULT ROUTER HOP LIMIT MANAGED ADDRESS
%token CONFIGURATION OTHER LIFETIME REACHABLE TIME RETRANS TIMER
%token AUTO PREFIX VALID PREFERRED LIFETIME ONLINK AUTONOMOUS
-%token ADDRESS_CONFIGURATION DNS NAMESERVER SEARCH MTU
+%token ADDRESS_CONFIGURATION DNS NAMESERVER SEARCH MTU NAT64
%token <v.string> STRING
%token <v.number> NUMBER
@@ -215,6 +219,51 @@ ra_opt_block : DEFAULT ROUTER yesno {
| MTU NUMBER {
ra_options->mtu = $2;
}
+ | NAT64 PREFIX STRING {
+ struct in6_addr addr;
+ int prefixlen;
+ char *p;
+ const char *errstr;
+
+ memset(&addr, 0, sizeof(addr));
+ p = strchr($3, '/');
+ if (p != NULL) {
+ *p++ = '\0';
+ prefixlen = strtonum(p, 0, 128, &errstr);
+ if (errstr != NULL) {
+ yyerror("error parsing prefix "
+ "\"%s/%s\"", $3, p);
+ free($3);
+ YYERROR;
+ }
+ } else
+ prefixlen = 96;
+
+ switch (prefixlen) {
+ case 96:
+ case 64:
+ case 56:
+ case 48:
+ case 40:
+ case 32:
+ break;
+ default:
+ yyerror("invalid nat64 prefix length: %d",
+ prefixlen);
+ YYERROR;
+ break;
+ }
+ if(inet_pton(AF_INET6, $3, &addr) == 0) {
+ yyerror("error parsing prefix \"%s/%d\"", $3,
+ prefixlen);
+ free($3);
+ YYERROR;
+ }
+ mask_prefix(&addr, prefixlen);
+ ra_pref64_conf = conf_get_ra_pref64(&addr, prefixlen);
+ } ra_pref64_block {
+ ra_pref64_conf = NULL;
+ }
| DNS dns_block
;
@@ -312,6 +361,21 @@ ra_prefixoptsl : VALID LIFETIME NUMBER {
ra_prefix_conf->aflag = $3;
}
;
+
+ra_pref64_block : '{' optnl ra_pref64opts_l '}'
+ | '{' optnl '}'
+ | /* empty */
+ ;
+
+ra_pref64opts_l : ra_pref64opts_l ra_pref64optsl nl
+ | ra_pref64optsl optnl
+ ;
+
+ra_pref64optsl : LIFETIME NUMBER {
+ ra_pref64_conf->ltime = $2;
+ }
+ ;
+
dns_block : '{' optnl dnsopts_l '}'
| '{' optnl '}'
| /* empty */
@@ -446,6 +510,7 @@ lookup(char *s)
{"managed", MANAGED},
{"mtu", MTU},
{"nameserver", NAMESERVER},
+ {"nat64", NAT64},
{"no", NO},
{"on-link", ONLINK},
{"other", OTHER},
@@ -853,6 +918,12 @@ parse_config(char *filename)
&iface->ra_options);
}
+ if (!SIMPLEQ_EMPTY(&conf->ra_options.ra_pref64_list)) {
+ SIMPLEQ_FOREACH(iface, &conf->ra_iface_list, entry)
+ copy_pref64_options(&conf->ra_options,
+ &iface->ra_options);
+ }
+
return (conf);
}
@@ -884,6 +955,20 @@ copy_dns_options(const struct ra_options_conf *src, struct
ra_options_conf *dst)
}
}
+void
+copy_pref64_options(const struct ra_options_conf *src, struct ra_options_conf
+ *dst)
+{
+ struct ra_pref64_conf *pref64, *npref64;
+
+ SIMPLEQ_FOREACH(pref64, &src->ra_pref64_list, entry) {
+ if ((npref64 = calloc(1, sizeof(*npref64))) == NULL)
+ errx(1, "%s", __func__);
+ memcpy(npref64, pref64, sizeof(*npref64));
+ SIMPLEQ_INSERT_TAIL(&dst->ra_pref64_list, npref64, entry);
+ }
+}
+
int
symset(const char *nam, const char *val, int persist)
{
@@ -991,6 +1076,28 @@ conf_get_ra_prefix(struct in6_addr *addr, int prefixlen)
return (prefix);
}
+struct ra_pref64_conf *
+conf_get_ra_pref64(struct in6_addr *addr, int prefixlen)
+{
+ struct ra_pref64_conf *pref64;
+
+ SIMPLEQ_FOREACH(pref64, &ra_options->ra_pref64_list, entry) {
+ if (pref64->prefixlen == prefixlen && memcmp(addr,
+ &pref64->prefix, sizeof(*addr)) == 0)
+ return (pref64);
+ }
+
+ pref64 = calloc(1, sizeof(*pref64));
+ if (pref64 == NULL)
+ errx(1, "%s: calloc", __func__);
+ pref64->prefixlen = prefixlen;
+ pref64->ltime = ADV_VALID_LIFETIME;
+ pref64->prefix = *addr;
+ SIMPLEQ_INSERT_TAIL(&ra_options->ra_pref64_list, pref64, entry);
+
+ return (pref64);
+}
+
struct ra_iface_conf *
conf_get_ra_iface(char *name)
{
@@ -1017,6 +1124,7 @@ conf_get_ra_iface(char *name)
iface->ra_options.rdnss_count = 0;
SIMPLEQ_INIT(&iface->ra_options.ra_dnssl_list);
iface->ra_options.dnssl_len = 0;
+ SIMPLEQ_INIT(&iface->ra_options.ra_pref64_list);
SIMPLEQ_INSERT_TAIL(&conf->ra_iface_list, iface, entry);
diff --git printconf.c printconf.c
index 78099534812..0204491983e 100644
--- printconf.c
+++ printconf.c
@@ -48,6 +48,7 @@ print_ra_options(const char *indent, const struct
ra_options_conf *ra_options)
{
struct ra_rdnss_conf *ra_rdnss;
struct ra_dnssl_conf *ra_dnssl;
+ struct ra_pref64_conf *pref64;
char buf[INET6_ADDRSTRLEN];
printf("%sdefault router %s\n", indent, yesno(ra_options->dfr));
@@ -84,6 +85,13 @@ print_ra_options(const char *indent, const struct
ra_options_conf *ra_options)
}
printf("%s}\n", indent);
}
+ SIMPLEQ_FOREACH(pref64, &ra_options->ra_pref64_list, entry) {
+ printf("%snat64 prefix %s/%d {\n", indent, inet_ntop(AF_INET6,
+ &pref64->prefix, buf, sizeof(buf)), pref64->prefixlen);
+ printf("%s\tlifetime %u\n", indent, pref64->ltime);
+ printf("%s}\n", indent);
+ }
+
}
void
diff --git rad.8 rad.8
index 8e023d9dbc6..551a010cd94 100644
--- rad.8
+++ rad.8
@@ -132,6 +132,14 @@ socket used for communication with
.%R RFC 8106
.%T IPv6 Router Advertisement Options for DNS Configuration
.Re
+.Pp
+.Rs
+.%A L. Colitti
+.%A J. Linkova
+.%D April 2020
+.%R RFC 8781
+.%T Discovering PREF64 in Router Advertisements
+.Re
.Sh HISTORY
The
.Nm
diff --git rad.c rad.c
index 3bb4851bdb3..2647f06bdf9 100644
--- rad.c
+++ rad.c
@@ -573,6 +573,7 @@ main_imsg_send_config(struct rad_conf *xconf)
struct ra_prefix_conf *ra_prefix_conf;
struct ra_rdnss_conf *ra_rdnss_conf;
struct ra_dnssl_conf *ra_dnssl_conf;
+ struct ra_pref64_conf *pref64;
/* Send fixed part of config to children. */
if (main_sendboth(IMSG_RECONF_CONF, xconf, sizeof(*xconf)) == -1)
@@ -592,6 +593,14 @@ main_imsg_send_config(struct rad_conf *xconf)
return (-1);
}
+ /* send global pref64 list to children */
+ SIMPLEQ_FOREACH(pref64, &xconf->ra_options.ra_pref64_list,
+ entry) {
+ if (main_sendboth(IMSG_RECONF_RA_PREF64, pref64,
+ sizeof(*pref64)) == -1)
+ return (-1);
+ }
+
/* Send the interface list to children. */
SIMPLEQ_FOREACH(ra_iface_conf, &xconf->ra_iface_list, entry) {
if (main_sendboth(IMSG_RECONF_RA_IFACE, ra_iface_conf,
@@ -621,6 +630,12 @@ main_imsg_send_config(struct rad_conf *xconf)
sizeof(*ra_dnssl_conf)) == -1)
return (-1);
}
+ SIMPLEQ_FOREACH(pref64,
+ &ra_iface_conf->ra_options.ra_pref64_list, entry) {
+ if (main_sendboth(IMSG_RECONF_RA_PREF64, pref64,
+ sizeof(*pref64)) == -1)
+ return (-1);
+ }
}
/* Tell children the revised config is now complete. */
@@ -644,6 +659,7 @@ void
free_ra_iface_conf(struct ra_iface_conf *ra_iface_conf)
{
struct ra_prefix_conf *prefix;
+ struct ra_pref64_conf *pref64;
if (!ra_iface_conf)
return;
@@ -658,6 +674,13 @@ free_ra_iface_conf(struct ra_iface_conf *ra_iface_conf)
free_dns_options(&ra_iface_conf->ra_options);
+ while ((pref64 =
+ SIMPLEQ_FIRST(&ra_iface_conf->ra_options.ra_pref64_list)) != NULL) {
+ SIMPLEQ_REMOVE_HEAD(&ra_iface_conf->ra_options.ra_pref64_list,
+ entry);
+ free(pref64);
+ }
+
free(ra_iface_conf);
}
@@ -684,6 +707,7 @@ void
merge_config(struct rad_conf *conf, struct rad_conf *xconf)
{
struct ra_iface_conf *ra_iface_conf;
+ struct ra_pref64_conf *pref64;
/* Remove & discard existing interfaces. */
while ((ra_iface_conf = SIMPLEQ_FIRST(&conf->ra_iface_list)) != NULL) {
@@ -692,9 +716,16 @@ merge_config(struct rad_conf *conf, struct rad_conf *xconf)
}
free_dns_options(&conf->ra_options);
+ while ((pref64 = SIMPLEQ_FIRST(&conf->ra_options.ra_pref64_list))
+ != NULL) {
+ SIMPLEQ_REMOVE_HEAD(&conf->ra_options.ra_pref64_list, entry);
+ free(pref64);
+ }
+
conf->ra_options = xconf->ra_options;
SIMPLEQ_INIT(&conf->ra_options.ra_rdnss_list);
SIMPLEQ_INIT(&conf->ra_options.ra_dnssl_list);
+ SIMPLEQ_INIT(&conf->ra_options.ra_pref64_list);
/* Add new interfaces. */
SIMPLEQ_CONCAT(&conf->ra_iface_list, &xconf->ra_iface_list);
@@ -704,6 +735,8 @@ merge_config(struct rad_conf *conf, struct rad_conf *xconf)
&xconf->ra_options.ra_rdnss_list);
SIMPLEQ_CONCAT(&conf->ra_options.ra_dnssl_list,
&xconf->ra_options.ra_dnssl_list);
+ SIMPLEQ_CONCAT(&conf->ra_options.ra_pref64_list,
+ &xconf->ra_options.ra_pref64_list);
free(xconf);
}
@@ -729,6 +762,7 @@ config_new_empty(void)
xconf->ra_options.rdns_lifetime = DEFAULT_RDNS_LIFETIME;
SIMPLEQ_INIT(&xconf->ra_options.ra_rdnss_list);
SIMPLEQ_INIT(&xconf->ra_options.ra_dnssl_list);
+ SIMPLEQ_INIT(&xconf->ra_options.ra_pref64_list);
return (xconf);
}
diff --git rad.conf.5 rad.conf.5
index b3ecf8c11be..ae42e5824fe 100644
--- rad.conf.5
+++ rad.conf.5
@@ -96,6 +96,21 @@ The MTU option is used in Router Advertisement messages to
ensure that all
nodes on a link use the same MTU value in those cases where the link MTU
is not well known.
The default is 0, meaning unspecified by this router.
+.It Ic nat64 prefix Ar prefix Oc Brq nat64 options
+Add a PREF64 router advertisement option to communicate prefixes used
+for Network Address and Protocol Translation from IPv6 to IPv4 (NAT64).
+If
+.Ar prefix
+is specified without a prefix length, its default is 64.
+.Pp
+.Ic nat64 prefix
+options are as follows:
+.Bl -tag -width Ds
+.It Ic lifetime Ar seconds
+The number of seconds the nat64 prefix option is valid after receiving a router
+advertisement message.
+The default is 2592000 seconds.
+.El
.It Ic other configuration Pq Ic yes Ns | Ns Ic no
If set to yes, hosts should consult DHCPv6 for additional configuration
like NTP servers or DNS name servers.
@@ -128,7 +143,7 @@ This can be disabled with
.Ic no auto prefix .
If
.Ar prefix
-is specified without prefixlen, its default is 64.
+is specified without a prefix length, its default is 64.
.Pp
.Ic prefix
options are as follows:
diff --git rad.h rad.h
index 9b0fedd77fb..77ad9b28c2a 100644
--- rad.h
+++ rad.h
@@ -55,6 +55,7 @@ enum imsg_type {
IMSG_RECONF_RA_PREFIX,
IMSG_RECONF_RA_RDNSS,
IMSG_RECONF_RA_DNSSL,
+ IMSG_RECONF_RA_PREF64,
IMSG_RECONF_END,
IMSG_ICMP6SOCK,
IMSG_OPEN_ICMP6SOCK,
@@ -78,6 +79,14 @@ struct ra_dnssl_conf {
char search[MAX_SEARCH];
};
+/* RFC 8781 Section 4 */
+struct ra_pref64_conf {
+ SIMPLEQ_ENTRY(ra_pref64_conf) entry;
+ struct in6_addr prefix; /* prefix */
+ int prefixlen; /* prefix length */
+ uint32_t ltime; /* lifetime */
+};
+
/* RFC 4861 Sections 4.2 and 4.6.4 */
struct ra_options_conf {
int dfr; /* is default router? */
@@ -93,6 +102,7 @@ struct ra_options_conf {
int rdnss_count;
SIMPLEQ_HEAD(, ra_dnssl_conf) ra_dnssl_list;
int dnssl_len;
+ SIMPLEQ_HEAD(, ra_pref64_conf) ra_pref64_list;
};
/* RFC 4861 Section 4.6.2 */
--
I'm not entirely sure you are real.
