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+21
View File
@@ -1,3 +1,24 @@
version 2.66
Add the ability to act as an authoritative DNS
server. Dnsmasq can now answer queries from the wider 'net
with local data, as long as the correct NS records are set
up. Only local data is provided, to avoid creating an open
DNS relay. Zone transfer is supported, to allow secondary
servers to be configured.
Add "constructed DHCP ranges" for DHCPv6. This is intended
for IPv6 routers which get prefixes dynamically via prefix
delegation. With suitable configuration, stateful DHCPv6
and RA can happen automatically as prefixes are delegated
and then deprecated, without having to re-write the
dnsmasq configuration file or restart the daemon. Thanks to
Steven Barth for extensive testing and development work on
this idea.
Fix crash on startup on Solaris 11. Regression probably
introduced in 2.61. Thanks to Geoff Johnstone for the patch.
version 2.65
Fix regression which broke forwarding of queries sent via
TCP which are not for A and AAAA and which were directed to
+171 -2
View File
@@ -75,6 +75,9 @@ the upstream DNS servers.
.B --max-cache-ttl=<time>
Set a maximum TTL value for entries in the cache.
.TP
.B --auth-ttl=<time>
Set the TTL value returned in answers from the authoritative server.
.TP
.B \-k, --keep-in-foreground
Do not go into the background at startup but otherwise run as
normal. This is intended for use when dnsmasq is run under daemontools
@@ -541,8 +544,27 @@ needed for a client to do validation itself.
.TP
.B --auth-zone=<domain>[,<subnet>[,<subnet>.....]]
Define a DNS zone for which dnsmasq acts as authoritative server. Locally defined DNS records which are in the domain
will be served, except that A and AAAA records must be in one of the specified subnets, or in a subnet corresponding to a contructed DHCP range. The subnet(s) are also used to define in-addr.arpa and ipv6.arpa domains which are served for reverse-DNS queries.
.TP
will be served, except that A and AAAA records must be in one of the
specified subnets, or in a subnet corresponding to a contructed DHCP
range. The subnet(s) are also used to define in-addr.arpa and
ipv6.arpa domains which are served for reverse-DNS queries.
.TP
.B --auth-soa=<serial>[,<hostmaster>[,<refresh>[,<retry>[,<expiry>]]]]
Specify fields in the SOA record associated with authoritative
zones. Note that this is optional, all the values are set to sane defaults.
.TP
.B --auth-sec-servers=<domain>[,<domain>[,<domain>...]]
Specify any secondary servers for a zone for which dnsmasq is
authoritative. These servers must be configured to get zone data from
dnsmasq by zone transfer, and answer queries for the same
authoritative zones and dnsmasq.
.TP
.B --auth-peer=<ip-address>[,<ip-address>[,<ip-address>...]]
Specify the addresses of secondary servers which are allowed to
initiate zone transfer (AXFR) requests for zones for which dnsmasq is
authoritative. If this option is not given, then AXFR requests wil be
accepted from any secondary.
.TP
.B --conntrack
Read the Linux connection track mark associated with incoming DNS
queries and set the same mark value on upstream traffic used to answer
@@ -1671,6 +1693,153 @@ parameter in a BOOTP request is used as a tag,
as is the tag "bootp", allowing some control over the options returned to
different classes of hosts.
.SH AUTHORITATIVE CONFIGURATION
.PP
Configuring dnsmasq to act as an authoritative DNS server is
complicated by the fact that it involves configuration of external DNS
servers to provide delegation. We will walk through three scenarios of
increasing complexity. Prerequisites for all of these scenarios
are a globally accesible IP address, an A or AAAA record pointing to that address,
and an external DNS server capable of doing delegation of the zone in
question. For the first part of this explanation, we will call the A (or AAAA) record
for the globally accessible address server.example.com, and the zone
for which dnsmasq is authoritative our.zone.com.
The simplest configuration consists of two lines of dnsmasq configuration; something like
.nf
.B auth-server=server.example.com,eth0
.B auth=zone=our.zone.com,1.2.3.0/24
.fi
and two records in the external DNS
.nf
server.example.com A 192.0.43.10
our.zone.com NS server.example.com
.fi
eth0 is the external network interface on which dnsmasq is listening,
and has (globally accessible) address 192.0.43.10.
Note that the external IP address may well be dynamic (ie assigned
from an ISP by DHCP or PPP) If so, the A record must be linked to this
dynamic assignment by one of the usual dynamic-DNS systems.
A more complex, but practically useful configuration has the address
record for the globally accessible IP address residing in the
authoritative zone which dnsmasq is serving, typically at the root. Now
we have
.nf
.B auth-server=our.zone.com,eth0
.B auth=zone=our.zone.com,1.2.3.0/24
.fi
.nf
our.zone.com A 192.0.43.10
our.zone.com NS our.zone.com
.fi
The A record for our.zone.com has now become a glue record, it solves
the chicken-and-egg problem of finding the IP address of the
nameserver for our.zone.com when the A record is within that
zone. Note that this is the only role of this record: as dnsmasq is
now authoritative from our.zone.com it too must provide this
record. If the external address is static, this can be done with an
.B /etc/hosts
entry or
.B --host-record.
If the external address is dynamic,
then it must be done using something like
.nf
.B --interface-name=our.zone.com,eth0
.fi
Our final configuration builds on that above, but also adds a
secondary DNS server. This is another DNS server which learns the DNS data
for the zone by doing zones transfer, and acts as a backup should
the primary server become inaccessible. The configuration of the
secondary is beyond the scope of this man-page, but the extra
configuration of dnsmasq is simple:
.nf
.B auth-sec-servers=secondary.myisp.com
.fi
and
.nf
our.zone.com NS secondary.myisp.com
.fi
Adding auth-sec-servers enables zone transfer in dnsmasq, to allow the
secondary to collect the DNS data. If you wish to restrict this data
to particular hosts then
.nf
.B auth-peer=<IP address of secondary>
.fi
will do so.
Dnsmasq acts as an authoritative server for in-addr.arpa and
ipv6.arpa domains associated with the subnets given in auth-zone
declarations, so reverse (address to name) lookups can be simply
configured with a suitable NS record, for instance in this example,
where we allow 1.2.3.0/24 addresses.
.nf
3.2.1.in-addr.arpa NS our.zone.com
.fi
Note that at present, reverse (in-addr.arpa and ip6.arpa) zones are
not available in zone transfers, so there is no point arranging
secondary servers for reverse lookups.
.PP
When dnsmasq is configured to act as an authoritative server, the
following data is used to populate the authoritative zone.
.PP
.B --mx-host, --srv-host, --dns-rr, --txt-record, --naptr-record
, as long as the record names are in the authoritative domain.
.PP
.B --cname
as long as the record name is in the authoritative domain. If the
target of the CNAME is unqualified, then it is qualified with the
authoritative zone name.
.PP
IPv4 and IPv6 addresses from /etc/hosts (and
.B --addn-hosts
) and
.B --host-record
provided the address falls into one of the subnets specified in the
.B --auth-zone.
.PP
Addresses specified by
.B --interface-name.
In this case, the address is not contrained to a subnet from
.B --auth-zone.
.PP
Addresses of DHCP leases, provided the address falls into one of the subnets specified in the
.B --auth-zone
OR a constructed DHCP range. In the default mode, where a DHCP lease
has an unqualified name, and possibly a qualified name constructed
using
.B --domain
then the name in the authoritative zone is constructed from the
unqualified name and the zone's domain. This may or may not equal
that specified by
.B --domain.
If
.B --dhcp-fqdn
is set, then the fully qualified names associated with DHCP leases are
used, and must match the zone's domain.
.SH EXIT CODES
.PP
0 - Dnsmasq successfully forked into the background, or terminated
+20 -22
View File
@@ -376,35 +376,33 @@ size_t answer_auth(struct dns_header *header, char *limit, size_t qlen, time_t n
}
else if (qtype == T_AXFR)
{
if (daemon->auth_peers)
struct iname *peers;
if (peer_addr->sa.sa_family == AF_INET)
peer_addr->in.sin_port = 0;
#ifdef HAVE_IPV6
else
peer_addr->in6.sin6_port = 0;
#endif
for (peers = daemon->auth_peers; peers; peers = peers->next)
if (sockaddr_isequal(peer_addr, &peers->addr))
break;
/* Refuse all AXFR unless --auth-sec-servers is set */
if ((!peers && daemon->auth_peers) || !daemon->secondary_forward_server)
{
struct iname *peers;
if (peer_addr->sa.sa_family == AF_INET)
peer_addr->in.sin_port = 0;
inet_ntop(AF_INET, &peer_addr->in.sin_addr, daemon->addrbuff, ADDRSTRLEN);
#ifdef HAVE_IPV6
else
peer_addr->in6.sin6_port = 0;
inet_ntop(AF_INET6, &peer_addr->in6.sin6_addr, daemon->addrbuff, ADDRSTRLEN);
#endif
for (peers = daemon->auth_peers; peers; peers = peers->next)
if (sockaddr_isequal(peer_addr, &peers->addr))
break;
if (!peers)
{
if (peer_addr->sa.sa_family == AF_INET)
inet_ntop(AF_INET, &peer_addr->in.sin_addr, daemon->addrbuff, ADDRSTRLEN);
#ifdef HAVE_IPV6
else
inet_ntop(AF_INET6, &peer_addr->in6.sin6_addr, daemon->addrbuff, ADDRSTRLEN);
#endif
my_syslog(LOG_WARNING, _("ignoring zone transfer request from %s"), daemon->addrbuff);
return 0;
}
my_syslog(LOG_WARNING, _("ignoring zone transfer request from %s"), daemon->addrbuff);
return 0;
}
soa = 1; /* inhibits auth section */
ns = 1; /* ensure we include NS records! */
axfr = 1;
+5 -2
View File
@@ -111,7 +111,7 @@ int iface_enumerate(int family, void *parm, int (*callback)())
{
int iface_index = if_nametoindex(addrs->ifa_name);
if (iface_index == 0)
if (iface_index == 0 || !addrs->ifa_addr || !addrs->ifa_netmask)
continue;
if (family == AF_INET)
@@ -119,7 +119,10 @@ int iface_enumerate(int family, void *parm, int (*callback)())
struct in_addr addr, netmask, broadcast;
addr = ((struct sockaddr_in *) addrs->ifa_addr)->sin_addr;
netmask = ((struct sockaddr_in *) addrs->ifa_netmask)->sin_addr;
broadcast = ((struct sockaddr_in *) addrs->ifa_broadaddr)->sin_addr;
if (addrs->ifa_broadaddr)
broadcast = ((struct sockaddr_in *) addrs->ifa_broadaddr)->sin_addr;
else
broadcast.s_addr = 0;
if (!((*callback)(addr, iface_index, netmask, broadcast, parm)))
goto err;
}
+36 -44
View File
@@ -679,7 +679,7 @@ void log_context(int family, struct dhcp_context *context)
void *start = &context->start;
void *end = &context->end;
char *n = "", *m = "", *p = daemon->namebuff;
char *template = "", *p = daemon->namebuff;
*p = 0;
@@ -694,67 +694,59 @@ void log_context(int family, struct dhcp_context *context)
end = &context->end6;
}
#endif
if ((context->flags & CONTEXT_DHCP) ||
!(context->flags & (CONTEXT_CONSTRUCTED | CONTEXT_TEMPLATE)))
if (family != AF_INET && (context->flags & CONTEXT_DEPRECATE))
strcpy(daemon->namebuff, _(", prefix deprecated"));
else
{
if (family != AF_INET && (context->flags & CONTEXT_DEPRECATE))
strcpy(daemon->namebuff, _(", prefix deprecated"));
else
{
p += sprintf(p, _(", lease time "));
m = p;
prettyprint_time(p, context->lease_time);
p += strlen(p);
}
}
p += sprintf(p, _(", lease time "));
prettyprint_time(p, context->lease_time);
p += strlen(p);
}
#ifdef HAVE_DHCP6
if (context->flags & CONTEXT_CONSTRUCTED)
{
char ifrn_name[IFNAMSIZ];
if (indextoname(daemon->doing_dhcp6 ? daemon->dhcp6fd : daemon->icmp6fd, context->if_index, ifrn_name))
{
n = p;
p += sprintf(p, ", constructed for %s", ifrn_name);
}
}
if (context->flags & CONTEXT_TEMPLATE)
{
n = p;
p += sprintf(p, ", template for %s%s", context->template_interface,
(context->flags & CONTEXT_WILDCARD) ? "*" : "");
}
{
char ifrn_name[IFNAMSIZ];
template = p;
p += sprintf(p, ", ");
if (indextoname(daemon->doing_dhcp6 ? daemon->dhcp6fd : daemon->icmp6fd, context->if_index, ifrn_name))
sprintf(p, "constructed for %s", ifrn_name);
}
else if (context->flags & CONTEXT_TEMPLATE)
{
template = p;
p += sprintf(p, ", ");
sprintf(p, "template for %s%s", context->template_interface,
(context->flags & CONTEXT_WILDCARD) ? "*" : "");
}
#endif
if ((context->flags & CONTEXT_DHCP) || family == AF_INET)
{
inet_ntop(family, start, daemon->dhcp_buff, 256);
inet_ntop(family, end, daemon->dhcp_buff3, 256);
my_syslog(MS_DHCP | LOG_INFO,
(context->flags & CONTEXT_RA_STATELESS) ?
_("%s stateless on %s%.0s%.0s") :
_("%s stateless on %s%.0s%.0s%s") :
(context->flags & CONTEXT_STATIC) ?
_("%s, static leases only on %.0s%s%s") :
_("%s, static leases only on %.0s%s%s%.0s") :
(context->flags & CONTEXT_PROXY) ?
_("%s, proxy on subnet %.0s%s%.0s") :
_("%s, IP range %s -- %s%s"),
_("%s, proxy on subnet %.0s%s%.0s%.0s") :
_("%s, IP range %s -- %s%s%.0s"),
(family != AF_INET) ? "DHCPv6" : "DHCP",
daemon->dhcp_buff, daemon->dhcp_buff3, daemon->namebuff);
daemon->dhcp_buff, daemon->dhcp_buff3, daemon->namebuff, template);
}
#ifdef HAVE_DHCP6
if (context->flags & CONTEXT_RA_NAME)
my_syslog(MS_DHCP | LOG_INFO, _("DHCPv4-derived IPv6 names on %s%s"),
daemon->addrbuff, n);
my_syslog(MS_DHCP | LOG_INFO, _("DHCPv4-derived IPv6 names on %s%s"), daemon->addrbuff, template);
if (context->flags & CONTEXT_RA)
my_syslog(MS_DHCP | LOG_INFO, _("router advertisement on %s%s%s"),
daemon->addrbuff,
(context->flags & (CONTEXT_CONSTRUCTED | CONTEXT_TEMPLATE)) ? "" : ", prefix valid ",
(context->flags & (CONTEXT_CONSTRUCTED | CONTEXT_TEMPLATE)) ? n : m);
if ((context->flags & CONTEXT_RA) || (option_bool(OPT_RA) && (context->flags & CONTEXT_DHCP) && family == AF_INET6))
my_syslog(MS_DHCP | LOG_INFO, _("router advertisement on %s%s"), daemon->addrbuff, template);
#endif
}
+24 -16
View File
@@ -211,7 +211,8 @@ static int complete_context6(struct in6_addr *local, int prefix,
for (context = daemon->dhcp6; context; context = context->next)
{
if (!(context->flags & CONTEXT_TEMPLATE) &&
if ((context->flags & CONTEXT_DHCP) &&
!(context->flags & CONTEXT_TEMPLATE) &&
prefix == context->prefix &&
is_same_net6(local, &context->start6, prefix) &&
is_same_net6(local, &context->end6, prefix))
@@ -328,6 +329,7 @@ int address6_allocate(struct dhcp_context *context, unsigned char *clid, int cl
return 0;
}
/* can dynamically allocate addr */
struct dhcp_context *address6_available(struct dhcp_context *context,
struct in6_addr *taddr,
struct dhcp_netid *netids)
@@ -352,6 +354,21 @@ struct dhcp_context *address6_available(struct dhcp_context *context,
return NULL;
}
/* address OK if configured */
struct dhcp_context *address6_valid(struct dhcp_context *context,
struct in6_addr *taddr,
struct dhcp_netid *netids)
{
struct dhcp_context *tmp;
for (tmp = context; tmp; tmp = tmp->current)
if (is_same_net6(&tmp->start6, taddr, tmp->prefix) &&
match_netid(tmp->filter, netids, 1))
return tmp;
return NULL;
}
struct dhcp_context *narrow_context6(struct dhcp_context *context,
struct in6_addr *taddr,
struct dhcp_netid *netids)
@@ -366,21 +383,12 @@ struct dhcp_context *narrow_context6(struct dhcp_context *context,
struct dhcp_context *tmp;
if (!(tmp = address6_available(context, taddr, netids)))
{
for (tmp = context; tmp; tmp = tmp->current)
if (match_netid(tmp->filter, netids, 1) &&
is_same_net6(taddr, &tmp->start6, tmp->prefix) &&
(tmp->flags & CONTEXT_STATIC))
break;
if (!tmp)
for (tmp = context; tmp; tmp = tmp->current)
if (match_netid(tmp->filter, netids, 1) &&
is_same_net6(taddr, &tmp->start6, tmp->prefix) &&
!(tmp->flags & CONTEXT_PROXY))
break;
}
if (!(tmp = address6_available(context, taddr, netids)) &&
!(tmp = address6_valid(context, taddr, netids)))
for (tmp = context; tmp; tmp = tmp->current)
if (match_netid(tmp->filter, netids, 1) &&
is_same_net6(taddr, &tmp->start6, tmp->prefix))
break;
/* Only one context allowed now */
if (tmp)
+3
View File
@@ -1149,6 +1149,9 @@ int is_addr_in_context6(struct dhcp_context *context, struct in6_addr *addr);
struct dhcp_context *address6_available(struct dhcp_context *context,
struct in6_addr *taddr,
struct dhcp_netid *netids);
struct dhcp_context *address6_valid(struct dhcp_context *context,
struct in6_addr *taddr,
struct dhcp_netid *netids);
struct dhcp_context *narrow_context6(struct dhcp_context *context,
struct in6_addr *taddr,
struct dhcp_netid *netids);
+1 -1
View File
@@ -392,7 +392,7 @@ static struct {
{ LOPT_RR, ARG_DUP, "<name>,<RR-number>,[<data>]", gettext_noop("Specify arbitrary DNS resource record"), NULL },
{ LOPT_CLVERBIND, OPT_CLEVERBIND, NULL, gettext_noop("Bind to interfaces in use - check for new interfaces"), NULL },
{ LOPT_AUTHSERV, ARG_ONE, "<NS>,<interface>", gettext_noop("Export local names to global DNS"), NULL },
{ LOPT_AUTHZONE, ARG_DUP, "<domain>,<subnet>[,<subnet>]", gettext_noop("Domain to export to global DNS"), NULL },
{ LOPT_AUTHZONE, ARG_DUP, "<domain>,[<subnet>...]", gettext_noop("Domain to export to global DNS"), NULL },
{ LOPT_AUTHTTL, ARG_ONE, "<integer>", gettext_noop("Set TTL for authoritative replies"), NULL },
{ LOPT_AUTHSOA, ARG_ONE, "<serial>[,...]", gettext_noop("Set authoritive zone information"), NULL },
{ LOPT_AUTHSFS, ARG_DUP, "<NS>[,<NS>...]", gettext_noop("Secondary authoritative nameservers for forward domains"), NULL },
+39 -31
View File
@@ -82,18 +82,20 @@ static int dhcp6_maybe_relay(struct in6_addr *link_address, struct dhcp_netid **
{
struct dhcp_context *c;
context = NULL;
if (!IN6_IS_ADDR_LOOPBACK(link_address) &&
!IN6_IS_ADDR_LINKLOCAL(link_address) &&
!IN6_IS_ADDR_MULTICAST(link_address))
for (c = daemon->dhcp6; c; c = c->next)
if ((c->flags & CONTEXT_DHCP) &&
!(c->flags & CONTEXT_TEMPLATE) &&
is_same_net6(link_address, &c->start6, c->prefix) &&
is_same_net6(link_address, &c->end6, c->prefix))
{
c->current = context;
context = c;
}
for (c = daemon->dhcp6; c; c = c->next)
if (!IN6_IS_ADDR_LOOPBACK(link_address) &&
!IN6_IS_ADDR_LINKLOCAL(link_address) &&
!IN6_IS_ADDR_MULTICAST(link_address) &&
is_same_net6(link_address, &c->start6, c->prefix) &&
is_same_net6(link_address, &c->end6, c->prefix))
{
c->current = context;
context = c;
}
if (!context)
{
inet_ntop(AF_INET6, link_address, daemon->addrbuff, ADDRSTRLEN);
@@ -525,32 +527,38 @@ static int dhcp6_no_relay(int msg_type, struct in6_addr *link_address, struct dh
{
struct in6_addr *req_addr = opt6_ptr(ia_option, 0);
requested_time = opt6_uint(ia_option, 16, 4);
if (!address6_available(context, req_addr, tags) &&
(!have_config(config, CONFIG_ADDR6) || memcmp(&config->addr6, req_addr, IN6ADDRSZ) != 0))
struct dhcp_context *dynamic;
if ((dynamic = address6_available(context, req_addr, tags)) || address6_valid(context, req_addr, tags))
{
if (msg_type == DHCP6REQUEST)
if (!dynamic && !(have_config(config, CONFIG_ADDR6) && memcmp(&config->addr6, req_addr, IN6ADDRSZ) == 0))
{
/* host has a lease, but it's not on the correct link */
/* Static range, not configured. */
o1 = new_opt6(OPTION6_STATUS_CODE);
put_opt6_short(DHCP6NOTONLINK);
put_opt6_string("Not on link");
put_opt6_short(DHCP6UNSPEC);
put_opt6_string("Address unavailable");
end_opt6(o1);
}
else if (lease6_find_by_addr(req_addr, 128, 0) &&
!(lease = lease6_find(clid, clid_len, ia_type == OPTION6_IA_NA ? LEASE_NA : LEASE_TA, iaid, req_addr)))
{
/* Address leased to another DUID/IAID */
o1 = new_opt6(OPTION6_STATUS_CODE);
put_opt6_short(DHCP6UNSPEC);
put_opt6_string("Address in use");
end_opt6(o1);
}
else
addrp = req_addr;
}
else if ((lease = lease6_find(NULL, 0, ia_type == OPTION6_IA_NA ? LEASE_NA : LEASE_TA,
iaid, req_addr)) &&
(clid_len != lease->clid_len ||
memcmp(clid, lease->clid, clid_len) != 0))
else if (msg_type == DHCP6REQUEST)
{
/* Address leased to another DUID */
/* requested address not on the correct link */
o1 = new_opt6(OPTION6_STATUS_CODE);
put_opt6_short(DHCP6UNSPEC);
put_opt6_string("Address in use");
put_opt6_short(DHCP6NOTONLINK);
put_opt6_string("Not on link");
end_opt6(o1);
}
else
addrp = req_addr;
}
}
else
{
@@ -567,9 +575,9 @@ static int dhcp6_no_relay(int msg_type, struct in6_addr *link_address, struct dh
inet_ntop(AF_INET6, &config->addr6, daemon->addrbuff, ADDRSTRLEN);
if (ltmp && ltmp->clid &&
(ltmp->clid_len != clid_len || memcmp(ltmp->clid, clid, clid_len) != 0))
my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it is leased to %s"),
daemon->addrbuff, print_mac(daemon->namebuff, ltmp->clid, ltmp->clid_len));
(ltmp->clid_len != clid_len || memcmp(ltmp->clid, clid, clid_len) != 0 || ltmp->hwaddr_type != iaid))
my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it is leased to %s:%d"),
daemon->addrbuff, print_mac(daemon->namebuff, ltmp->clid, ltmp->clid_len), lease->hwaddr_type);
else if (have_config(config, CONFIG_DECLINED) &&
difftime(now, config->decline_time) < (float)DECLINE_BACKOFF)
my_syslog(MS_DHCP | LOG_WARNING, _("not using configured address %s because it was previously declined"),