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Author SHA1 Message Date
Simon Kelley d05dd58de1 Fix wrong reply to simple name when --domain-needed set and no servers configured.
Also return REFUSED and not SERVFAIL when out of memory.

Thanks to Allain Legacy for problem report.
2016-01-19 21:23:30 +00:00
Simon Kelley f7443d76f7 Fix problems in last commit when DNSSEC not enabled. 2016-01-19 20:29:57 +00:00
Simon Kelley f344dbc622 Complete DNSSEC server-selection code and set conntrack on DNSSEC queries. 2016-01-18 18:11:54 +00:00
Simon Kelley f4d0c660ca Fix sporadic crash in find_mac() - hwlen must be zero for empty entries. 2016-01-18 12:51:08 +00:00
Simon Kelley 1801a29226 Fix botch in forward.c flags code.
Thanks to Matthias Anfree for spotting this.
2016-01-17 21:53:57 +00:00
Simon Kelley 92be34a407 Complete work to allow DNSSEC validation with private DNS servers. 2016-01-16 18:39:54 +00:00
6 changed files with 189 additions and 57 deletions

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+9
View File
@@ -22,6 +22,15 @@ version 2.76
reading a hosts-file fails. Thanks to André Glüpker
for the patch.
Fix wrong answer to simple name query when --domain-needed
set, but no upstream servers configured. Dnsmasq returned
REFUSED, in this case, when it should be the same as when
upstream servers are configured - NOERROR. Thanks to
Allain Legacy for spotting the problem.
Return REFUSED when running out of forwarding table slots,
not SERVFAIL.
version 2.75
Fix reversion on 2.74 which caused 100% CPU use when a
+4 -1
View File
@@ -405,7 +405,10 @@ xxx.internal.thekelleys.org.uk at 192.168.1.1 then giving the flag
.B -S /internal.thekelleys.org.uk/192.168.1.1
will send all queries for
internal machines to that nameserver, everything else will go to the
servers in /etc/resolv.conf. An empty domain specification,
servers in /etc/resolv.conf. DNSSEC validation is turned off for such
private nameservers, UNLESS a
.B --trust-anchor
is specified for the domain in question. An empty domain specification,
.B //
has the special meaning of "unqualified names only" ie names without any
dots in them. A non-standard port may be specified as
+2 -1
View File
@@ -188,7 +188,8 @@ int find_mac(union mysockaddr *addr, unsigned char *mac, int lazy, time_t now)
arps = arp;
arp->status = ARP_EMPTY;
arp->family = addr->sa.sa_family;
arp->hwlen = 0;
if (addr->sa.sa_family == AF_INET)
arp->addr.addr.addr4.s_addr = addr->in.sin_addr.s_addr;
#ifdef HAVE_IPV6
+154 -38
View File
@@ -151,7 +151,7 @@ static unsigned int search_servers(time_t now, struct all_addr **addrpp, unsigne
hostname_isequal(matchstart, serv->domain) &&
(domainlen == 0 || namelen == domainlen || *(matchstart-1) == '.' ))
{
if (serv->flags & SERV_NO_REBIND)
if ((serv->flags & SERV_NO_REBIND) && norebind)
*norebind = 1;
else
{
@@ -249,9 +249,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
(void)do_bit;
/* may be no servers available. */
if (!daemon->servers)
forward = NULL;
else if (forward || (hash && (forward = lookup_frec_by_sender(ntohs(header->id), udpaddr, hash))))
if (forward || (hash && (forward = lookup_frec_by_sender(ntohs(header->id), udpaddr, hash))))
{
/* If we didn't get an answer advertising a maximal packet in EDNS,
fall back to 1280, which should work everywhere on IPv6.
@@ -331,12 +329,12 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
#ifdef HAVE_DNSSEC
do_dnssec = type & SERV_DO_DNSSEC;
type &= ~SERV_DO_DNSSEC;
#endif
#endif
type &= ~SERV_DO_DNSSEC;
if (!flags && !(forward = get_new_frec(now, NULL, 0)))
/* table full - server failure. */
flags = F_NEG;
if (daemon->servers && !flags)
forward = get_new_frec(now, NULL, 0);
/* table full - flags == 0, return REFUSED */
if (forward)
{
@@ -644,7 +642,7 @@ static size_t process_reply(struct dns_header *header, time_t now, struct server
return resize_packet(header, n, pheader, plen);
/* Complain loudly if the upstream server is non-recursive. */
if (!(header->hb4 & HB4_RA) && RCODE(header) == NOERROR && ntohs(header->ancount) == 0 &&
if (!(header->hb4 & HB4_RA) && RCODE(header) == NOERROR &&
server && !(server->flags & SERV_WARNED_RECURSIVE))
{
prettyprint_addr(&server->addr, daemon->namebuff);
@@ -810,9 +808,9 @@ void reply_query(int fd, int family, time_t now)
{
header->hb3 &= ~(HB3_QR | HB3_AA | HB3_TC);
header->hb4 &= ~(HB4_RA | HB4_RCODE | HB4_CD | HB4_AD);
if (forward->flags |= FREC_CHECKING_DISABLED)
if (forward->flags & FREC_CHECKING_DISABLED)
header->hb4 |= HB4_CD;
if (forward->flags |= FREC_AD_QUESTION)
if (forward->flags & FREC_AD_QUESTION)
header->hb4 |= HB4_AD;
if (forward->flags & FREC_DO_QUESTION)
add_do_bit(header, nn, (unsigned char *)pheader + plen);
@@ -923,12 +921,48 @@ void reply_query(int fd, int family, time_t now)
status = STAT_ABANDONED;
else
{
int fd;
int fd, type = SERV_DO_DNSSEC;
struct frec *next = new->next;
char *domain;
*new = *forward; /* copy everything, then overwrite */
new->next = next;
new->blocking_query = NULL;
/* Find server to forward to. This will normally be the
same as for the original query, but may be another if
servers for domains are involved. */
if (search_servers(now, NULL, F_QUERY, daemon->keyname, &type, &domain, NULL) == 0)
{
struct server *start = server, *new_server = NULL;
type &= ~SERV_DO_DNSSEC;
while (1)
{
if (type == (start->flags & SERV_TYPE) &&
(type != SERV_HAS_DOMAIN || hostname_isequal(domain, start->domain)) &&
!(start->flags & (SERV_LITERAL_ADDRESS | SERV_LOOP)))
{
new_server = start;
if (server == start)
{
new_server = NULL;
break;
}
}
if (!(start = start->next))
start = daemon->servers;
if (start == server)
break;
}
if (new_server)
server = new_server;
}
new->sentto = server;
new->rfd4 = NULL;
#ifdef HAVE_IPV6
new->rfd6 = NULL;
@@ -982,6 +1016,15 @@ void reply_query(int fd, int family, time_t now)
if (fd != -1)
{
#ifdef HAVE_CONNTRACK
/* Copy connection mark of incoming query to outgoing connection. */
if (option_bool(OPT_CONNTRACK))
{
unsigned int mark;
if (get_incoming_mark(&orig->source, &orig->dest, 0, &mark))
setsockopt(fd, SOL_SOCKET, SO_MARK, &mark, sizeof(unsigned int));
}
#endif
while (retry_send(sendto(fd, (char *)header, nn, 0,
&server->addr.sa,
sa_len(&server->addr))));
@@ -1044,7 +1087,7 @@ void reply_query(int fd, int family, time_t now)
else
header->hb4 &= ~HB4_CD;
if ((nn = process_reply(header, now, server, (size_t)n, check_rebind, no_cache_dnssec, cache_secure, bogusanswer,
if ((nn = process_reply(header, now, forward->sentto, (size_t)n, check_rebind, no_cache_dnssec, cache_secure, bogusanswer,
forward->flags & FREC_AD_QUESTION, forward->flags & FREC_DO_QUESTION,
forward->flags & FREC_ADDED_PHEADER, forward->flags & FREC_HAS_SUBNET, &forward->source)))
{
@@ -1405,20 +1448,24 @@ void receive_query(struct listener *listen, time_t now)
}
#ifdef HAVE_DNSSEC
/* Recurse up the key heirarchy */
static int tcp_key_recurse(time_t now, int status, struct dns_header *header, size_t n,
int class, char *name, char *keyname, struct server *server, int *keycount)
int class, char *name, char *keyname, struct server *server,
int have_mark, unsigned int mark, int *keycount)
{
/* Recurse up the key heirarchy */
int new_status;
unsigned char *packet = NULL;
size_t m;
unsigned char *payload = NULL;
struct dns_header *new_header = NULL;
u16 *length = NULL;
unsigned char c1, c2;
while (1)
{
int type = SERV_DO_DNSSEC;
char *domain;
size_t m;
unsigned char c1, c2;
/* limit the amount of work we do, to avoid cycling forever on loops in the DNS */
if (--(*keycount) == 0)
new_status = STAT_ABANDONED;
@@ -1452,6 +1499,67 @@ static int tcp_key_recurse(time_t now, int status, struct dns_header *header, si
new_status == STAT_NEED_KEY ? T_DNSKEY : T_DS, &server->addr, server->edns_pktsz);
*length = htons(m);
/* Find server to forward to. This will normally be the
same as for the original query, but may be another if
servers for domains are involved. */
if (search_servers(now, NULL, F_QUERY, keyname, &type, &domain, NULL) == 0)
{
struct server *start = server, *new_server = NULL;
type &= ~SERV_DO_DNSSEC;
while (1)
{
if (type == (start->flags & SERV_TYPE) &&
(type != SERV_HAS_DOMAIN || hostname_isequal(domain, start->domain)) &&
!(start->flags & (SERV_LITERAL_ADDRESS | SERV_LOOP)))
{
new_server = start;
if (server == start)
{
new_server = NULL;
break;
}
}
if (!(start = start->next))
start = daemon->servers;
if (start == server)
break;
}
if (new_server)
{
server = new_server;
/* may need to make new connection. */
if (server->tcpfd == -1)
{
if ((server->tcpfd = socket(server->addr.sa.sa_family, SOCK_STREAM, 0)) == -1)
{
new_status = STAT_ABANDONED;
break;
}
#ifdef HAVE_CONNTRACK
/* Copy connection mark of incoming query to outgoing connection. */
if (have_mark)
setsockopt(server->tcpfd, SOL_SOCKET, SO_MARK, &mark, sizeof(unsigned int));
#endif
if (!local_bind(server->tcpfd, &server->source_addr, server->interface, 1) ||
connect(server->tcpfd, &server->addr.sa, sa_len(&server->addr)) == -1)
{
close(server->tcpfd);
server->tcpfd = -1;
new_status = STAT_ABANDONED;
break;
}
}
}
}
if (!read_write(server->tcpfd, packet, m + sizeof(u16), 0) ||
!read_write(server->tcpfd, &c1, 1, 1) ||
@@ -1464,7 +1572,7 @@ static int tcp_key_recurse(time_t now, int status, struct dns_header *header, si
m = (c1 << 8) | c2;
new_status = tcp_key_recurse(now, new_status, new_header, m, class, name, keyname, server, keycount);
new_status = tcp_key_recurse(now, new_status, new_header, m, class, name, keyname, server, have_mark, mark, keycount);
if (new_status != STAT_OK)
break;
@@ -1508,10 +1616,31 @@ unsigned char *tcp_request(int confd, time_t now,
socklen_t peer_len = sizeof(union mysockaddr);
int query_count = 0;
unsigned char *pheader;
unsigned int mark = 0;
int have_mark = 0;
(void)mark;
(void)have_mark;
if (getpeername(confd, (struct sockaddr *)&peer_addr, &peer_len) == -1)
return packet;
#ifdef HAVE_CONNTRACK
/* Get connection mark of incoming query to set on outgoing connections. */
if (option_bool(OPT_CONNTRACK))
{
struct all_addr local;
#ifdef HAVE_IPV6
if (local_addr->sa.sa_family == AF_INET6)
local.addr.addr6 = local_addr->in6.sin6_addr;
else
#endif
local.addr.addr4 = local_addr->in.sin_addr;
have_mark = get_incoming_mark(&peer_addr, &local, 1, &mark);
}
#endif
/* We can be configured to only accept queries from at-most-one-hop-away addresses. */
if (option_bool(OPT_LOCAL_SERVICE))
{
@@ -1637,7 +1766,7 @@ unsigned char *tcp_request(int confd, time_t now,
{
unsigned int flags = 0;
struct all_addr *addrp = NULL;
int type = 0;
int type = SERV_DO_DNSSEC;
char *domain = NULL;
size_t new_size = add_edns0_config(header, size, ((unsigned char *) header) + 65536, &peer_addr, now, &check_subnet);
@@ -1650,9 +1779,7 @@ unsigned char *tcp_request(int confd, time_t now,
if (gotname)
flags = search_servers(now, &addrp, gotname, daemon->namebuff, &type, &domain, &norebind);
#ifdef HAVE_DNSSEC
type &= ~SERV_DO_DNSSEC;
#endif
if (type != 0 || option_bool(OPT_ORDER) || !daemon->last_server)
last_server = daemon->servers;
@@ -1700,20 +1827,8 @@ unsigned char *tcp_request(int confd, time_t now,
#ifdef HAVE_CONNTRACK
/* Copy connection mark of incoming query to outgoing connection. */
if (option_bool(OPT_CONNTRACK))
{
unsigned int mark;
struct all_addr local;
#ifdef HAVE_IPV6
if (local_addr->sa.sa_family == AF_INET6)
local.addr.addr6 = local_addr->in6.sin6_addr;
else
#endif
local.addr.addr4 = local_addr->in.sin_addr;
if (get_incoming_mark(&peer_addr, &local, 1, &mark))
setsockopt(last_server->tcpfd, SOL_SOCKET, SO_MARK, &mark, sizeof(unsigned int));
}
if (have_mark)
setsockopt(last_server->tcpfd, SOL_SOCKET, SO_MARK, &mark, sizeof(unsigned int));
#endif
if ((!local_bind(last_server->tcpfd, &last_server->source_addr, last_server->interface, 1) ||
@@ -1774,7 +1889,8 @@ unsigned char *tcp_request(int confd, time_t now,
if (option_bool(OPT_DNSSEC_VALID) && !checking_disabled && (last_server->flags & SERV_DO_DNSSEC))
{
int keycount = DNSSEC_WORK; /* Limit to number of DNSSEC questions, to catch loops and avoid filling cache. */
int status = tcp_key_recurse(now, STAT_OK, header, m, 0, daemon->namebuff, daemon->keyname, last_server, &keycount);
int status = tcp_key_recurse(now, STAT_OK, header, m, 0, daemon->namebuff, daemon->keyname,
last_server, have_mark, mark, &keycount);
char *result, *domain = "result";
if (status == STAT_ABANDONED)
+19 -14
View File
@@ -1442,20 +1442,25 @@ void check_servers(void)
if (!(serv->flags & (SERV_LITERAL_ADDRESS | SERV_NO_ADDR | SERV_USE_RESOLV | SERV_NO_REBIND)))
{
#ifdef HAVE_DNSSEC
if (option_bool(OPT_DNSSEC_VALID) && (serv->flags & SERV_HAS_DOMAIN))
{
struct ds_config *ds;
char *domain = serv->domain;
/* .example.com is valid */
while (*domain == '.')
domain++;
for (ds = daemon->ds; ds; ds = ds->next)
if (ds->name[0] != 0 && hostname_isequal(domain, ds->name))
break;
if (!ds)
if (option_bool(OPT_DNSSEC_VALID))
{
if (serv->flags & SERV_HAS_DOMAIN)
{
struct ds_config *ds;
char *domain = serv->domain;
/* .example.com is valid */
while (*domain == '.')
domain++;
for (ds = daemon->ds; ds; ds = ds->next)
if (ds->name[0] != 0 && hostname_isequal(domain, ds->name))
break;
if (!ds)
serv->flags &= ~SERV_DO_DNSSEC;
}
else if (serv->flags & SERV_FOR_NODOTS)
serv->flags &= ~SERV_DO_DNSSEC;
}
#endif
+1 -3
View File
@@ -896,9 +896,7 @@ size_t setup_reply(struct dns_header *header, size_t qlen,
header->nscount = htons(0);
header->arcount = htons(0);
header->ancount = htons(0); /* no answers unless changed below */
if (flags == F_NEG)
SET_RCODE(header, SERVFAIL); /* couldn't get memory */
else if (flags == F_NOERR)
if (flags == F_NOERR)
SET_RCODE(header, NOERROR); /* empty domain */
else if (flags == F_NXDOMAIN)
SET_RCODE(header, NXDOMAIN);