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19 Commits
Author SHA1 Message Date
Simon Kelley da58455508 Tweak 7d915a0bb9
A downstream query may have gone to TCP, not just DNSSEC queries.
2025-01-13 11:03:30 +00:00
Simon Kelley b915c9a661 Attempt to keep running if a child process dies.
If a child process dies unexpectedly, log the error and
try and tidy up so the main process continues to run and
doesn't block awaiting the dead child.
2025-01-13 10:56:19 +00:00
Simon Kelley 424aaa0f9d Fix another 509afcd1d2 SNAFU 2025-01-13 10:32:55 +00:00
Andrew Sayers c72c895869 Improve "no upstream servers configured" when D-Bus is enabled
Print a specific INFO message instead of a generic WARNING message,
so users know what to do.

Starting dnsmasq without upstream servers indicates a problem by default,
but is perfectly normal with D-Bus enabled.  For example, NetworkManager
starts dnsmasq with no upstream servers, then immediately populates it
over D-Bus.
2025-01-12 22:32:32 +00:00
Simon Kelley b7156116c2 Fix SNAFU in 509afcd1d2 2025-01-12 22:28:12 +00:00
Simon Kelley 7d915a0bb9 Don't do retries over UDP when we've sent the query by TCP. 2025-01-12 22:02:05 +00:00
Simon Kelley 509afcd1d2 Refactor poll() loop.
Handling events on file descriptors can result in new file
descriptors being created or old ones being deleted. As such
the results of the last call to poll() become invalid in subtle
ways.

After handling each file descriptor in  check_dns_listeners()
return, to go around the poll() loop again and get valid data
for the new situation.

Thanks to Dominik Derigs for his indefatigable sleuthing of this one.
2025-01-12 21:36:09 +00:00
Simon Kelley 51343bd9a2 Treat replies with CD flag set the same for UDP and TCP code paths. 2025-01-12 16:25:07 +00:00
Simon Kelley b58276a73c Return EDE OTHER error when DNSSEC validation abandoned.
This distinguishes the case where we found a message was bogus
from cases where the process failed.
2025-01-12 16:00:09 +00:00
Matthias Andree f162d344c0 cache: Fix potential NULL deref in arcane situations. 2025-01-08 23:34:12 +00:00
Simon Kelley 0003db15cb Fix crash introduced in 6656790f24 2025-01-07 23:08:35 +00:00
Simon Kelley 275f4a4475 Remove arbitrary workspace size limit.
I have no memory for why this was ever there. It breaks DNSSEC
validation of large RRsets.

I can't see any DoS potential that is exposed by removing it.
2025-01-07 21:41:30 +00:00
Andrew Sayers 12e4565fef Improve "chown of PID file failed" message for missing CAP_CHOWN
Print a specific INFO message instead of a generic WARNING message,
so users aren't inconvenienced and maintainers know what to do.

Debian currently runs this service as part of NetworkManager,
in a systemd service without CAP_CHOWN.  Other distributions may
have the same problem, or might add the issue in future.
This fix should communicate the issue clearly to them.
2025-01-07 21:03:25 +00:00
Andrew Sayers 7af26eed32 Fix manpage typo.
s/will we/will be/
2025-01-07 21:01:15 +00:00
Simon Kelley 63dc6eb316 Fix read_write() changes for TCP timeout.
I misread the man page for socket(7) and TCP timeouts.

A timeout generates a -1 return and EAGAIN errno, NOT a short read.

Short reads are legit, and aborting when they are seen creates
hard-to-reproduce errors.
2025-01-07 20:53:03 +00:00
Simon Kelley 6656790f24 Handle queries with EDNS client subnet fields better.
If dnsmasq is configured to add an EDNS client subnet to a query,
it is careful to suppress use of the cache, since a cached answer may
not be valid for a query with a different client subnet.
Extend this behaviour to queries which arrive a dnsmasq
already carrying an EDNS client subnet.

This change is rather more involved than may seem necessary at first sight,
since the existing code relies on all queries being decorated by dnsmasq
and therefore not cached, so there is no chance that an incoming query
might hit the cache and cache lookup don't need to be suppressed, just
cache insertion. When downstream queries may be a mix of client-subnet
bearing and plain vanilla, it can't be assumed that the answers are never
in the cache, and queries with subnets must not do lookups.
2025-01-07 20:46:33 +00:00
Simon Kelley c8de423038 Fix finger-trouble in immediately previous commit. 2025-01-07 17:00:18 +00:00
Simon Kelley c52653f97c Correctly handle failure of pipe() call in swap_to_tcp() 2025-01-06 23:16:40 +00:00
Simon Kelley e24c341068 Fix wrong packet size when dumpong packets to file. 2025-01-01 17:03:50 +00:00
11 changed files with 444 additions and 358 deletions

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+7
View File
@@ -75,7 +75,14 @@ version 2.91
Fix erroneous "DNSSEC validated" state with non-DNSSEC
upstream servers. Thanks to Dominik Derigs for the bug report.
Handle queries with EDNS client subnet fields better. If dnsmasq
is configured to add an EDNS client subnet to a query, it is careful
to suppress use of the cache, since a cached answer may not be valid
for a query with a different client subnet. Extend this behaviour
to queries which arrive a dnsmasq already carrying an EDNS client
subnet.
version 2.90
Fix reversion in --rev-server introduced in 2.88 which
caused breakage if the prefix length is not exactly divisible
+1 -1
Submodule debian updated: 05f03dca94...83e05da879.
+1 -1
View File
@@ -1429,7 +1429,7 @@ forces "simple and safe" behaviour to avoid problems in such a case.
.B --dhcp-relay=<local address>[,<server address>[#<server port>]][,<interface]
Configure dnsmasq to do DHCP relay. The local address is an address
allocated to an interface on the host running dnsmasq. All DHCP
requests arriving on that interface will we relayed to a remote DHCP
requests arriving on that interface will be relayed to a remote DHCP
server at the server address. It is possible to relay from a single local
address to multiple remote servers by using multiple \fB--dhcp-relay\fP
configs with the same local address and different server
+1 -1
View File
@@ -479,7 +479,7 @@ static struct crec *cache_scan_free(char *name, union all_addr *addr, unsigned s
if ((crecp->flags & F_FORWARD) && hostname_isequal(cache_get_name(crecp), name))
{
int rrmatch = 0;
if (crecp->flags & flags & F_RR)
if (addr && (crecp->flags & flags & F_RR))
{
unsigned short rrc = (crecp->flags & F_KEYTAG) ? crecp->addr.rrblock.rrtype : crecp->addr.rrdata.rrtype;
unsigned short rra = (flags & F_KEYTAG) ? addr->rrblock.rrtype : addr->rrdata.rrtype;
+293 -227
View File
@@ -32,6 +32,7 @@ static volatile int pipewrite;
static void set_dns_listeners(void);
static void set_tftp_listeners(void);
static void check_dns_listeners(time_t now);
static void do_tcp_connection(struct listener *listener, time_t now, int slot);
static void sig_handler(int sig);
static void async_event(int pipe, time_t now);
static void fatal_event(struct event_desc *ev, char *msg);
@@ -61,6 +62,7 @@ int main (int argc, char **argv)
int need_cap_net_admin = 0;
int need_cap_net_raw = 0;
int need_cap_net_bind_service = 0;
int have_cap_chown = 0;
char *bound_device = NULL;
int did_bind = 0;
struct server *serv;
@@ -556,6 +558,8 @@ int main (int argc, char **argv)
data = safe_malloc(sizeof(*data) * capsize);
capget(hdr, data); /* Get current values, for verification */
have_cap_chown = data->permitted & (1 << CAP_CHOWN);
if (need_cap_net_admin && !(data->permitted & (1 << CAP_NET_ADMIN)))
fail = "NET_ADMIN";
else if (need_cap_net_raw && !(data->permitted & (1 << CAP_NET_RAW)))
@@ -869,7 +873,14 @@ int main (int argc, char **argv)
my_syslog(LOG_INFO, _("compile time options: %s"), compile_opts);
if (chown_warn != 0)
my_syslog(LOG_WARNING, "chown of PID file %s failed: %s", daemon->runfile, strerror(chown_warn));
{
#if defined(HAVE_LINUX_NETWORK)
if (chown_warn == EPERM && !have_cap_chown)
my_syslog(LOG_INFO, "chown of PID file %s failed: please add capability CAP_CHOWN", daemon->runfile);
else
#endif
my_syslog(LOG_WARNING, "chown of PID file %s failed: %s", daemon->runfile, strerror(chown_warn));
}
#ifdef HAVE_DBUS
if (option_bool(OPT_DBUS))
@@ -951,7 +962,14 @@ int main (int argc, char **argv)
my_syslog(LOG_WARNING, _("warning: ignoring resolv-file flag because no-resolv is set"));
daemon->resolv_files = NULL;
if (!daemon->servers)
my_syslog(LOG_WARNING, _("warning: no upstream servers configured"));
{
#ifdef HAVE_DBUS
if (option_bool(OPT_DBUS))
my_syslog(LOG_INFO, _("no upstream servers configured - please set them from DBus"));
else
#endif
my_syslog(LOG_WARNING, _("warning: no upstream servers configured"));
}
}
if (daemon->max_logs != 0)
@@ -1466,7 +1484,7 @@ static void async_event(int pipe, time_t now)
{
pid_t p;
struct event_desc ev;
int i, check = 0;
int wstatus, i, check = 0;
char *msg;
/* NOTE: the memory used to return msg is leaked: use msgs in events only
@@ -1529,7 +1547,7 @@ static void async_event(int pipe, time_t now)
case EVENT_CHILD:
/* See Stevens 5.10 */
while ((p = waitpid(-1, NULL, WNOHANG)) != 0)
while ((p = waitpid(-1, &wstatus, WNOHANG)) != 0)
if (p == -1)
{
if (errno != EINTR)
@@ -1540,6 +1558,20 @@ static void async_event(int pipe, time_t now)
if (daemon->tcp_pids[i] == p)
{
daemon->tcp_pids[i] = 0;
if (!WIFEXITED(wstatus))
{
/* If a helper process dies, (eg with SIGSEV)
log that and attempt to patch things up so that the
parent can continue to function. */
my_syslog(LOG_WARNING, _("TCP helper process %u died unexpectedly"), (unsigned int)p);
if (daemon->tcp_pipes[i] != -1)
{
close(daemon->tcp_pipes[i]);
daemon->tcp_pipes[i] = -1;
}
}
/* tcp_pipes == -1 && tcp_pids == 0 required to free slot */
if (daemon->tcp_pipes[i] == -1)
daemon->metrics[METRIC_TCP_CONNECTIONS]--;
@@ -1822,247 +1854,281 @@ static void check_dns_listeners(time_t now)
struct listener *listener;
struct randfd_list *rfl;
int i;
int pipefd[2];
/* Note that handling events here can create or destroy fds and
render the result of the last poll() call invalid. Once
we find an fd that needs service, do it, then return to go around the
poll() loop again. This avoid really, really, wierd bugs. */
if (!option_bool(OPT_DEBUG))
for (i = 0; i < daemon->max_procs; i++)
if (daemon->tcp_pipes[i] != -1 &&
poll_check(daemon->tcp_pipes[i], POLLIN | POLLHUP))
{
/* Races. The child process can die before we read all of the data from the
pipe, or vice versa. Therefore send tcp_pids to zero when we wait() the
process, and tcp_pipes to -1 and close the FD when we read the last
of the data - indicated by cache_recv_insert returning zero.
The order of these events is indeterminate, and both are needed
to free the process slot. Once the child process has gone, poll()
returns POLLHUP, not POLLIN, so have to check for both here. */
if (!cache_recv_insert(now, daemon->tcp_pipes[i]))
{
close(daemon->tcp_pipes[i]);
daemon->tcp_pipes[i] = -1;
/* tcp_pipes == -1 && tcp_pids == 0 required to free slot */
if (daemon->tcp_pids[i] == 0)
daemon->metrics[METRIC_TCP_CONNECTIONS]--;
}
return;
}
for (serverfdp = daemon->sfds; serverfdp; serverfdp = serverfdp->next)
if (poll_check(serverfdp->fd, POLLIN))
reply_query(serverfdp->fd, now);
{
reply_query(serverfdp->fd, now);
return;
}
for (i = 0; i < daemon->numrrand; i++)
if (daemon->randomsocks[i].refcount != 0 &&
poll_check(daemon->randomsocks[i].fd, POLLIN))
reply_query(daemon->randomsocks[i].fd, now);
{
reply_query(daemon->randomsocks[i].fd, now);
return;
}
/* Check overflow random sockets too. */
for (rfl = daemon->rfl_poll; rfl; rfl = rfl->next)
if (poll_check(rfl->rfd->fd, POLLIN))
reply_query(rfl->rfd->fd, now);
/* Races. The child process can die before we read all of the data from the
pipe, or vice versa. Therefore send tcp_pids to zero when we wait() the
process, and tcp_pipes to -1 and close the FD when we read the last
of the data - indicated by cache_recv_insert returning zero.
The order of these events is indeterminate, and both are needed
to free the process slot. Once the child process has gone, poll()
returns POLLHUP, not POLLIN, so have to check for both here. */
if (!option_bool(OPT_DEBUG))
for (i = 0; i < daemon->max_procs; i++)
if (daemon->tcp_pipes[i] != -1 &&
poll_check(daemon->tcp_pipes[i], POLLIN | POLLHUP) &&
!cache_recv_insert(now, daemon->tcp_pipes[i]))
{
close(daemon->tcp_pipes[i]);
daemon->tcp_pipes[i] = -1;
/* tcp_pipes == -1 && tcp_pids == 0 required to free slot */
if (daemon->tcp_pids[i] == 0)
daemon->metrics[METRIC_TCP_CONNECTIONS]--;
}
{
reply_query(rfl->rfd->fd, now);
return;
}
for (listener = daemon->listeners; listener; listener = listener->next)
{
if (listener->fd != -1 && poll_check(listener->fd, POLLIN))
if (listener->fd != -1 && poll_check(listener->fd, POLLIN))
{
receive_query(listener, now);
/* check to see if we have a free tcp process slot.
Note that we can't assume that because we had
at least one a poll() time, that we still do.
There may be more waiting connections after
poll() returns then free process slots. */
for (i = daemon->max_procs - 1; i >= 0; i--)
if (daemon->tcp_pids[i] == 0 && daemon->tcp_pipes[i] == -1)
break;
return;
}
/* check to see if we have a free tcp process slot.
Note that we can't assume that because we had
at least one a poll() time, that we still do.
There may be more waiting connections after
poll() returns then free process slots. */
for (i = daemon->max_procs - 1; i >= 0; i--)
if (daemon->tcp_pids[i] == 0 && daemon->tcp_pipes[i] == -1)
break;
if (listener->tcpfd != -1 && i >= 0 && poll_check(listener->tcpfd, POLLIN))
if (i >= 0)
for (listener = daemon->listeners; listener; listener = listener->next)
if (listener->tcpfd != -1 && poll_check(listener->tcpfd, POLLIN))
{
int confd, client_ok = 1;
struct irec *iface = NULL;
pid_t p;
union mysockaddr tcp_addr;
socklen_t tcp_len = sizeof(union mysockaddr);
do_tcp_connection(listener, now, i);
return;
}
}
while ((confd = accept(listener->tcpfd, NULL, NULL)) == -1 && errno == EINTR);
if (confd == -1)
continue;
if (getsockname(confd, (struct sockaddr *)&tcp_addr, &tcp_len) == -1)
{
close(confd);
continue;
}
/* Make sure that the interface list is up-to-date.
We do this here as we may need the results below, and
the DNS code needs them for --interface-name stuff.
static void do_tcp_connection(struct listener *listener, time_t now, int slot)
{
int confd, client_ok = 1;
struct irec *iface = NULL;
pid_t p;
union mysockaddr tcp_addr;
socklen_t tcp_len = sizeof(union mysockaddr);
unsigned char a = 0, *buff;
struct server *s;
int flags, auth_dns;
struct in_addr netmask;
int pipefd[2];
Multiple calls to enumerate_interfaces() per select loop are
inhibited, so calls to it in the child process (which doesn't select())
have no effect. This avoids two processes reading from the same
netlink fd and screwing the pooch entirely.
*/
enumerate_interfaces(0);
while ((confd = accept(listener->tcpfd, NULL, NULL)) == -1 && errno == EINTR);
if (confd == -1)
return;
if (getsockname(confd, (struct sockaddr *)&tcp_addr, &tcp_len) == -1)
{
closeconandreturn:
shutdown(confd, SHUT_RDWR);
close(confd);
return;
}
/* Make sure that the interface list is up-to-date.
We do this here as we may need the results below, and
the DNS code needs them for --interface-name stuff.
Multiple calls to enumerate_interfaces() per select loop are
inhibited, so calls to it in the child process (which doesn't select())
have no effect. This avoids two processes reading from the same
netlink fd and screwing the pooch entirely.
*/
enumerate_interfaces(0);
if (option_bool(OPT_NOWILD))
iface = listener->iface; /* May be NULL */
else
{
int if_index;
char intr_name[IF_NAMESIZE];
/* if we can find the arrival interface, check it's one that's allowed */
if ((if_index = tcp_interface(confd, tcp_addr.sa.sa_family)) != 0 &&
indextoname(listener->tcpfd, if_index, intr_name))
{
union all_addr addr;
if (option_bool(OPT_NOWILD))
iface = listener->iface; /* May be NULL */
else
{
int if_index;
char intr_name[IF_NAMESIZE];
/* if we can find the arrival interface, check it's one that's allowed */
if ((if_index = tcp_interface(confd, tcp_addr.sa.sa_family)) != 0 &&
indextoname(listener->tcpfd, if_index, intr_name))
{
union all_addr addr;
if (tcp_addr.sa.sa_family == AF_INET6)
addr.addr6 = tcp_addr.in6.sin6_addr;
else
addr.addr4 = tcp_addr.in.sin_addr;
for (iface = daemon->interfaces; iface; iface = iface->next)
if (iface->index == if_index &&
iface->addr.sa.sa_family == tcp_addr.sa.sa_family)
break;
if (!iface && !loopback_exception(listener->tcpfd, tcp_addr.sa.sa_family, &addr, intr_name))
client_ok = 0;
}
if (option_bool(OPT_CLEVERBIND))
iface = listener->iface; /* May be NULL */
else
{
/* Check for allowed interfaces when binding the wildcard address:
we do this by looking for an interface with the same address as
the local address of the TCP connection, then looking to see if that's
an allowed interface. As a side effect, we get the netmask of the
interface too, for localisation. */
for (iface = daemon->interfaces; iface; iface = iface->next)
if (sockaddr_isequal(&iface->addr, &tcp_addr))
break;
if (!iface)
client_ok = 0;
}
}
if (!client_ok)
{
shutdown(confd, SHUT_RDWR);
close(confd);
}
else if (!option_bool(OPT_DEBUG) && pipe(pipefd) == 0 && (p = fork()) != 0)
{
close(pipefd[1]); /* parent needs read pipe end. */
if (p == -1)
close(pipefd[0]);
else
{
#ifdef HAVE_LINUX_NETWORK
/* The child process inherits the netlink socket,
which it never uses, but when the parent (us)
uses it in the future, the answer may go to the
child, resulting in the parent blocking
forever awaiting the result. To avoid this
the child closes the netlink socket, but there's
a nasty race, since the parent may use netlink
before the child has done the close.
To avoid this, the parent blocks here until a
single byte comes back up the pipe, which
is sent by the child after it has closed the
netlink socket. */
unsigned char a;
read_write(pipefd[0], &a, 1, RW_READ);
#endif
/* i holds index of free slot */
daemon->tcp_pids[i] = p;
daemon->tcp_pipes[i] = pipefd[0];
daemon->metrics[METRIC_TCP_CONNECTIONS]++;
if (daemon->metrics[METRIC_TCP_CONNECTIONS] > daemon->max_procs_used)
daemon->max_procs_used = daemon->metrics[METRIC_TCP_CONNECTIONS];
}
close(confd);
/* The child can use up to TCP_MAX_QUERIES ids, so skip that many. */
daemon->log_id += TCP_MAX_QUERIES;
#ifdef HAVE_DNSSEC
/* It can do more if making DNSSEC queries too. */
if (option_bool(OPT_DNSSEC_VALID))
daemon->log_id += daemon->limit[LIMIT_WORK];
#endif
}
if (tcp_addr.sa.sa_family == AF_INET6)
addr.addr6 = tcp_addr.in6.sin6_addr;
else
{
unsigned char *buff;
struct server *s;
int flags;
struct in_addr netmask;
int auth_dns;
if (iface)
{
netmask = iface->netmask;
auth_dns = iface->dns_auth;
}
else
{
netmask.s_addr = 0;
auth_dns = 0;
}
/* Arrange for SIGALRM after CHILD_LIFETIME seconds to
terminate the process. */
if (!option_bool(OPT_DEBUG))
{
#ifdef HAVE_LINUX_NETWORK
/* See comment above re: netlink socket. */
unsigned char a = 0;
close(daemon->netlinkfd);
read_write(pipefd[1], &a, 1, RW_WRITE);
#endif
alarm(CHILD_LIFETIME);
close(pipefd[0]); /* close read end in child. */
daemon->pipe_to_parent = pipefd[1];
}
/* The connected socket inherits non-blocking
attribute from the listening socket.
Reset that here. */
if ((flags = fcntl(confd, F_GETFL, 0)) != -1)
while(retry_send(fcntl(confd, F_SETFL, flags & ~O_NONBLOCK)));
buff = tcp_request(confd, now, &tcp_addr, netmask, auth_dns);
if (buff)
free(buff);
for (s = daemon->servers; s; s = s->next)
if (s->tcpfd != -1)
{
shutdown(s->tcpfd, SHUT_RDWR);
close(s->tcpfd);
s->tcpfd = -1;
}
if (!option_bool(OPT_DEBUG))
{
close(daemon->pipe_to_parent);
flush_log();
_exit(0);
}
}
addr.addr4 = tcp_addr.in.sin_addr;
for (iface = daemon->interfaces; iface; iface = iface->next)
if (iface->index == if_index &&
iface->addr.sa.sa_family == tcp_addr.sa.sa_family)
break;
if (!iface && !loopback_exception(listener->tcpfd, tcp_addr.sa.sa_family, &addr, intr_name))
client_ok = 0;
}
if (option_bool(OPT_CLEVERBIND))
iface = listener->iface; /* May be NULL */
else
{
/* Check for allowed interfaces when binding the wildcard address:
we do this by looking for an interface with the same address as
the local address of the TCP connection, then looking to see if that's
an allowed interface. As a side effect, we get the netmask of the
interface too, for localisation. */
for (iface = daemon->interfaces; iface; iface = iface->next)
if (sockaddr_isequal(&iface->addr, &tcp_addr))
break;
if (!iface)
client_ok = 0;
}
}
if (!client_ok)
goto closeconandreturn;
if (!option_bool(OPT_DEBUG))
{
if (pipe(pipefd) == -1)
goto closeconandreturn; /* pipe failed */
if ((p = fork()) == -1)
{
/* fork failed */
close(pipefd[0]);
close(pipefd[1]);
goto closeconandreturn;
}
if (p != 0)
{
/* fork() done: parent side */
close(pipefd[1]); /* parent needs read pipe end. */
#ifdef HAVE_LINUX_NETWORK
/* The child process inherits the netlink socket,
which it never uses, but when the parent (us)
uses it in the future, the answer may go to the
child, resulting in the parent blocking
forever awaiting the result. To avoid this
the child closes the netlink socket, but there's
a nasty race, since the parent may use netlink
before the child has done the close.
To avoid this, the parent blocks here until a
single byte comes back up the pipe, which
is sent by the child after it has closed the
netlink socket. */
read_write(pipefd[0], &a, 1, RW_READ);
#endif
daemon->tcp_pids[slot] = p;
daemon->tcp_pipes[slot] = pipefd[0];
daemon->metrics[METRIC_TCP_CONNECTIONS]++;
if (daemon->metrics[METRIC_TCP_CONNECTIONS] > daemon->max_procs_used)
daemon->max_procs_used = daemon->metrics[METRIC_TCP_CONNECTIONS];
close(confd);
/* The child can use up to TCP_MAX_QUERIES ids, so skip that many. */
daemon->log_id += TCP_MAX_QUERIES;
#ifdef HAVE_DNSSEC
/* It can do more if making DNSSEC queries too. */
if (option_bool(OPT_DNSSEC_VALID))
daemon->log_id += daemon->limit[LIMIT_WORK];
#endif
return;
}
}
if (iface)
{
netmask = iface->netmask;
auth_dns = iface->dns_auth;
}
else
{
netmask.s_addr = 0;
auth_dns = 0;
}
/* Arrange for SIGALRM after CHILD_LIFETIME seconds to
terminate the process. */
if (!option_bool(OPT_DEBUG))
{
#ifdef HAVE_LINUX_NETWORK
/* See comment above re: netlink socket. */
close(daemon->netlinkfd);
read_write(pipefd[1], &a, 1, RW_WRITE);
#endif
alarm(CHILD_LIFETIME);
close(pipefd[0]); /* close read end in child. */
daemon->pipe_to_parent = pipefd[1];
}
/* The connected socket inherits non-blocking
attribute from the listening socket.
Reset that here. */
if ((flags = fcntl(confd, F_GETFL, 0)) != -1)
while(retry_send(fcntl(confd, F_SETFL, flags & ~O_NONBLOCK)));
buff = tcp_request(confd, now, &tcp_addr, netmask, auth_dns);
if (buff)
free(buff);
for (s = daemon->servers; s; s = s->next)
if (s->tcpfd != -1)
{
shutdown(s->tcpfd, SHUT_RDWR);
close(s->tcpfd);
s->tcpfd = -1;
}
if (!option_bool(OPT_DEBUG))
{
close(daemon->pipe_to_parent);
flush_log();
_exit(0);
}
}
#ifdef HAVE_DNSSEC
/* If a DNSSEC query over UDP returns a truncated answer,
we swap to the TCP path. This routine is responsible for forking
@@ -2091,11 +2157,11 @@ int swap_to_tcp(struct frec *forward, time_t now, int status, struct dns_header
if (daemon->tcp_pids[i] == 0 && daemon->tcp_pipes[i] == -1)
break;
/* No slots */
if (i < 0)
/* No slots or no pipe */
if (i < 0 || pipe(pipefd) != 0)
return STAT_ABANDONED;
if (pipe(pipefd) == 0 && (p = fork()) != 0)
if ((p = fork()) != 0)
{
close(pipefd[1]); /* parent needs read pipe end. */
if (p == -1)
+3 -4
View File
@@ -772,9 +772,8 @@ struct dyndir {
#define FREC_DS_QUERY 16
#define FREC_AD_QUESTION 32
#define FREC_DO_QUESTION 64
#define FREC_ADDED_PHEADER 128
#define FREC_HAS_PHEADER 256
#define FREC_GONE_TO_TCP 512
#define FREC_HAS_PHEADER 128
#define FREC_GONE_TO_TCP 256
struct frec {
struct frec_src {
@@ -1402,7 +1401,7 @@ void report_addresses(struct dns_header *header, size_t len, u32 mark);
#endif
size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
struct in_addr local_addr, struct in_addr local_netmask,
time_t now, int ad_reqd, int do_bit, int *stale, int *filtered);
time_t now, int ad_reqd, int do_bit, int no_cache, int *stale, int *filtered);
int check_for_bogus_wildcard(struct dns_header *header, size_t qlen, char *name,
time_t now);
int check_for_ignored_address(struct dns_header *header, size_t qlen);
+29 -11
View File
@@ -417,21 +417,34 @@ static size_t add_source_addr(struct dns_header *header, size_t plen, unsigned c
else if (option_bool(OPT_STRIP_ECS))
replace = 2;
else
return plen;
{
unsigned char *pheader;
/* If we still think the data is cacheable, and we're not
messing with EDNS client subnet ourselves, see if the client
sent a client subnet. If so, mark the data as uncacheable */
if (*cacheable &&
(pheader = find_pseudoheader(header, plen, NULL, NULL, NULL, NULL)) &&
!check_source(header, plen, pheader, NULL))
*cacheable = 0;
return plen;
}
return add_pseudoheader(header, plen, (unsigned char *)limit, EDNS0_OPTION_CLIENT_SUBNET, (unsigned char *)&opt, len, 0, replace);
}
int check_source(struct dns_header *header, size_t plen, unsigned char *pseudoheader, union mysockaddr *peer)
{
/* Section 9.2, Check that subnet option in reply matches. */
/* Section 9.2, Check that subnet option (if any) in reply matches.
if peer == NULL, this degrades to a check for the existence of and EDNS0 client-subnet option. */
int len, calc_len;
struct subnet_opt opt;
unsigned char *p;
int code, i, rdlen;
calc_len = calc_subnet_opt(&opt, peer, NULL);
if (peer)
calc_len = calc_subnet_opt(&opt, peer, NULL);
if (!(p = skip_name(pseudoheader, header, plen, 10)))
return 1;
@@ -443,21 +456,26 @@ int check_source(struct dns_header *header, size_t plen, unsigned char *pseudohe
return 1; /* bad packet */
/* check if option there */
for (i = 0; i + 4 < rdlen; i += len + 4)
for (i = 0; i + 4 < rdlen; i += len + 4)
{
GETSHORT(code, p);
GETSHORT(len, p);
if (code == EDNS0_OPTION_CLIENT_SUBNET)
{
/* make sure this doesn't mismatch. */
opt.scope_netmask = p[3];
if (len != calc_len || memcmp(p, &opt, len) != 0)
if (peer)
{
/* make sure this doesn't mismatch. */
opt.scope_netmask = p[3];
if (len != calc_len || memcmp(p, &opt, len) != 0)
return 0;
}
else if (((struct subnet_opt *)p)->source_netmask != 0)
return 0;
}
p += len;
}
return 1;
return 1;
}
/* See https://docs.umbrella.com/umbrella-api/docs/identifying-dns-traffic for
@@ -541,6 +559,6 @@ size_t add_edns0_config(struct dns_header *header, size_t plen, unsigned char *l
plen = add_umbrella_opt(header, plen, limit, source, cacheable);
plen = add_source_addr(header, plen, limit, source, cacheable);
return plen;
}
+76 -86
View File
@@ -163,37 +163,22 @@ static int domain_no_rebind(char *domain)
return 0;
}
static int forward_query(int udpfd, union mysockaddr *udpaddr,
union all_addr *dst_addr, unsigned int dst_iface,
struct dns_header *header, size_t plen, size_t replylimit, time_t now,
struct frec *forward, int ad_reqd, int do_bit, int fast_retry)
static void forward_query(int udpfd, union mysockaddr *udpaddr,
union all_addr *dst_addr, unsigned int dst_iface,
struct dns_header *header, size_t plen, size_t replylimit, time_t now,
struct frec *forward, unsigned int fwd_flags, int fast_retry)
{
unsigned int flags = 0;
unsigned int fwd_flags = 0;
int is_dnssec = forward && (forward->flags & (FREC_DNSKEY_QUERY | FREC_DS_QUERY));
struct server *master;
unsigned int gotname;
int old_src = 0, old_reply = 0;
int first, last, start = 0;
int cacheable, forwarded = 0;
unsigned char *oph;
int forwarded = 0;
int ede = EDE_UNSET;
(void)do_bit;
unsigned short rrtype;
gotname = extract_request(header, plen, daemon->namebuff, &rrtype);
oph = find_pseudoheader(header, plen, NULL, NULL, NULL, NULL);
if (header->hb4 & HB4_CD)
fwd_flags |= FREC_CHECKING_DISABLED;
if (ad_reqd)
fwd_flags |= FREC_AD_QUESTION;
if (oph)
fwd_flags |= FREC_HAS_PHEADER;
#ifdef HAVE_DNSSEC
if (do_bit)
fwd_flags |= FREC_DO_QUESTION;
#endif
/* Check for retry on existing query.
FREC_DNSKEY and FREC_DS_QUERY are never set in flags, so the test below
@@ -205,6 +190,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
{
old_src = 1;
old_reply = 1;
fwd_flags = forward->flags;
}
else if (gotname && (forward = lookup_frec(daemon->namebuff, C_IN, (int)rrtype, -1, fwd_flags,
FREC_CHECKING_DISABLED | FREC_AD_QUESTION | FREC_DO_QUESTION |
@@ -268,7 +254,7 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
it's safe to wait for the reply from the first without
forwarding the second. */
if (difftime(now, forward->time) < 2)
return 0;
return;
}
/* use our id when resending */
@@ -321,11 +307,6 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
forward->flags = fwd_flags;
plen = add_edns0_config(header, plen, ((unsigned char *)header) + daemon->edns_pktsz, &forward->frec_src.source, now, &cacheable);
if (!cacheable)
forward->flags |= FREC_NO_CACHE;
#ifdef HAVE_DNSSEC
if (option_bool(OPT_DNSSEC_VALID) && (master->flags & SERV_DO_DNSSEC))
{
@@ -338,10 +319,6 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
}
#endif
/* If there wasn't a PH before, and there is now, we added it. */
if (!oph && find_pseudoheader(header, plen, NULL, NULL, NULL, NULL))
forward->flags |= FREC_ADDED_PHEADER;
/* Do these before saving query. */
forward->frec_src.orig_id = ntohs(header->id);
forward->new_id = get_id();
@@ -365,15 +342,9 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
forward->forwardall = 0;
if (domain_no_rebind(daemon->namebuff))
forward->flags |= FREC_NOREBIND;
if (header->hb4 & HB4_CD)
forward->flags |= FREC_CHECKING_DISABLED;
if (ad_reqd)
forward->flags |= FREC_AD_QUESTION;
#ifdef HAVE_DNSSEC
forward->work_counter = daemon->limit[LIMIT_WORK];
forward->validate_counter = daemon->limit[LIMIT_CRYPTO];
if (do_bit)
forward->flags |= FREC_DO_QUESTION;
#endif
start = first;
@@ -403,6 +374,10 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
while (forward->blocking_query)
forward = forward->blocking_query;
/* Don't retry if we've already sent it via TCP. */
if (forward->flags & FREC_GONE_TO_TCP)
return;
if (forward->flags & (FREC_DNSKEY_QUERY | FREC_DS_QUERY))
{
/* log_id should match previous DNSSEC query. */
@@ -415,8 +390,8 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
/* Find suitable servers: should never fail. */
if (!filter_servers(forward->sentto->arrayposn, F_DNSSECOK, &first, &last))
return 0;
return;
is_dnssec = 1;
forward->forwardall = 1;
}
@@ -531,8 +506,9 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
if (forwarded || is_dnssec)
{
daemon->metrics[METRIC_DNS_QUERIES_FORWARDED]++;
forward->forward_timestamp = dnsmasq_milliseconds();
return 1;
return;
}
/* could not send on, prepare to return */
@@ -544,16 +520,16 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
if (udpfd != -1)
{
if (!(plen = make_local_answer(flags, gotname, plen, header, daemon->namebuff, (char *)(header + replylimit), first, last, ede)))
return 0;
return;
if (oph)
if (fwd_flags & FREC_HAS_PHEADER)
{
u16 swap = htons((u16)ede);
if (ede != EDE_UNSET)
plen = add_pseudoheader(header, plen, (unsigned char *)(header + replylimit), EDNS0_OPTION_EDE, (unsigned char *)&swap, 2, do_bit, 0);
plen = add_pseudoheader(header, plen, (unsigned char *)(header + replylimit), EDNS0_OPTION_EDE, (unsigned char *)&swap, 2, 0, 0);
else
plen = add_pseudoheader(header, plen, (unsigned char *)(header + replylimit), 0, NULL, 0, do_bit, 0);
plen = add_pseudoheader(header, plen, (unsigned char *)(header + replylimit), 0, NULL, 0, 0, 0);
}
#if defined(HAVE_CONNTRACK) && defined(HAVE_UBUS)
@@ -572,7 +548,8 @@ static int forward_query(int udpfd, union mysockaddr *udpaddr,
send_from(udpfd, option_bool(OPT_NOWILD) || option_bool(OPT_CLEVERBIND), (char *)header, plen, udpaddr, dst_addr, dst_iface);
}
return 0;
daemon->metrics[METRIC_DNS_LOCAL_ANSWERED]++;
return;
}
/* Check if any frecs need to do a retry, and action that if so.
@@ -611,8 +588,7 @@ int fast_retry(time_t now)
daemon->log_display_id = f->frec_src.log_id;
daemon->log_source_addr = NULL;
forward_query(-1, NULL, NULL, 0, header, f->stash_len, 0, now, f,
f->flags & FREC_AD_QUESTION, f->flags & FREC_DO_QUESTION, 1);
forward_query(-1, NULL, NULL, 0, header, f->stash_len, 0, now, f, 0, 1);
to_run = f->forward_delay = 2 * f->forward_delay;
}
@@ -810,10 +786,9 @@ static size_t process_reply(struct dns_header *header, time_t now, struct server
header->ancount = htons(0);
header->nscount = htons(0);
header->arcount = htons(0);
ede = EDE_DNSSEC_BOGUS;
}
}
else if (!(header->hb4 & HB4_CD) && ad_reqd && cache_secure)
else if (ad_reqd && cache_secure)
header->hb4 |= HB4_AD;
/* If the requestor didn't set the DO bit, don't return DNSSEC info. */
@@ -1192,8 +1167,7 @@ void reply_query(int fd, time_t now)
/* Get the saved query back. */
blockdata_retrieve(forward->stash, forward->stash_len, (void *)header);
forward_query(-1, NULL, NULL, 0, header, forward->stash_len, 0, now, forward,
forward->flags & FREC_AD_QUESTION, forward->flags & FREC_DO_QUESTION, 0);
forward_query(-1, NULL, NULL, 0, header, forward->stash_len, 0, now, forward, 0, 0);
return;
}
@@ -1275,20 +1249,25 @@ void return_reply(time_t now, struct frec *forward, struct dns_header *header, s
char *result, *domain = "result";
union all_addr a;
a.log.ede = ede = errflags_to_ede(status);
ede = errflags_to_ede(status);
if (STAT_ISEQUAL(status, STAT_ABANDONED))
{
result = "ABANDONED";
status = STAT_BOGUS;
if (ede == EDE_UNSET)
ede = EDE_OTHER;
}
else
result = (STAT_ISEQUAL(status, STAT_SECURE) ? "SECURE" : (STAT_ISEQUAL(status, STAT_INSECURE) ? "INSECURE" : "BOGUS"));
if (STAT_ISEQUAL(status, STAT_SECURE))
cache_secure = 1;
else if (STAT_ISEQUAL(status, STAT_BOGUS))
{
if (ede == EDE_UNSET)
ede = EDE_DNSSEC_BOGUS;
no_cache_dnssec = 1;
bogusanswer = 1;
@@ -1296,6 +1275,7 @@ void return_reply(time_t now, struct frec *forward, struct dns_header *header, s
domain = daemon->namebuff;
}
a.log.ede = ede;
log_query(F_SECSTAT, domain, &a, result, 0);
}
}
@@ -1315,7 +1295,7 @@ void return_reply(time_t now, struct frec *forward, struct dns_header *header, s
header->hb4 |= HB4_CD;
else
header->hb4 &= ~HB4_CD;
/* Never cache answers which are contingent on the source or MAC address EDSN0 option,
since the cache is ignorant of such things. */
if (forward->flags & FREC_NO_CACHE)
@@ -1323,7 +1303,7 @@ void return_reply(time_t now, struct frec *forward, struct dns_header *header, s
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->frec_src.source,
!(forward->flags & FREC_HAS_PHEADER), &forward->frec_src.source,
((unsigned char *)header) + daemon->edns_pktsz, ede)))
{
struct frec_src *src;
@@ -1391,7 +1371,7 @@ void return_reply(time_t now, struct frec *forward, struct dns_header *header, s
&src->source, &src->dest, src->iface);
#ifdef HAVE_DUMPFILE
dump_packet_udp(DUMP_REPLY, daemon->packet, (size_t)nn, NULL, &src->source, src->fd);
dump_packet_udp(DUMP_REPLY, daemon->packet, (size_t)new, NULL, &src->source, src->fd);
#endif
}
}
@@ -1454,9 +1434,10 @@ void receive_query(struct listener *listen, time_t now)
struct in_addr netmask, dst_addr_4;
size_t m;
ssize_t n;
int if_index = 0, auth_dns = 0, do_bit = 0, have_pseudoheader = 0;
int if_index = 0, auth_dns = 0, do_bit = 0;
unsigned int fwd_flags = 0;
int stale = 0, filtered = 0, ede = EDE_UNSET, do_forward = 0;
int metric, ad_reqd, fd;
int metric, fd;
struct blockdata *saved_question = NULL;
#ifdef HAVE_CONNTRACK
unsigned int mark = 0;
@@ -1734,7 +1715,8 @@ void receive_query(struct listener *listen, time_t now)
{
unsigned short flags;
have_pseudoheader = 1;
fwd_flags |= FREC_HAS_PHEADER;
GETSHORT(udp_size, pheader);
pheader += 2; /* ext_rcode */
GETSHORT(flags, pheader);
@@ -1752,10 +1734,15 @@ void receive_query(struct listener *listen, time_t now)
udp_size = PACKETSZ; /* Sanity check - can't reduce below default. RFC 6891 6.2.3 */
}
ad_reqd = do_bit;
/* RFC 6840 5.7 */
if (header->hb4 & HB4_AD)
ad_reqd = 1;
if (do_bit || (header->hb4 & HB4_AD))
fwd_flags |= FREC_AD_QUESTION;
if (do_bit)
fwd_flags |= FREC_DO_QUESTION;
if (header->hb4 & HB4_CD)
fwd_flags |= FREC_CHECKING_DISABLED;
fd = listen->fd;
@@ -1790,10 +1777,16 @@ void receive_query(struct listener *listen, time_t now)
#endif
else
{
int cacheable;
n = add_edns0_config(header, n, ((unsigned char *)header) + daemon->edns_pktsz, &source_addr, now, &cacheable);
saved_question = blockdata_alloc((char *) header, (size_t)n);
if (!cacheable)
fwd_flags |= FREC_NO_CACHE;
m = answer_request(header, ((char *) header) + udp_size, (size_t)n,
dst_addr_4, netmask, now, ad_reqd, do_bit, &stale, &filtered);
dst_addr_4, netmask, now, fwd_flags & FREC_AD_QUESTION, do_bit, !cacheable, &stale, &filtered);
metric = stale ? METRIC_DNS_STALE_ANSWERED : METRIC_DNS_LOCAL_ANSWERED;
@@ -1814,7 +1807,7 @@ void receive_query(struct listener *listen, time_t now)
if (m != 0)
{
if (have_pseudoheader)
if (fwd_flags & FREC_HAS_PHEADER)
{
if (ede != EDE_UNSET)
{
@@ -1863,12 +1856,9 @@ void receive_query(struct listener *listen, time_t now)
blockdata_retrieve(saved_question, (size_t)n, (void *)header);
blockdata_free(saved_question);
saved_question = NULL;
if (forward_query(fd, &source_addr, &dst_addr, if_index, header, (size_t)n,
udp_size, now, NULL, ad_reqd, do_bit, 0))
daemon->metrics[METRIC_DNS_QUERIES_FORWARDED]++;
else
daemon->metrics[METRIC_DNS_LOCAL_ANSWERED]++;
forward_query(fd, &source_addr, &dst_addr, if_index, header, (size_t)n,
udp_size, now, NULL, fwd_flags, 0);
}
blockdata_free(saved_question);
@@ -2212,7 +2202,7 @@ unsigned char *tcp_request(int confd, time_t now,
#ifdef HAVE_AUTH
int local_auth = 0;
#endif
int checking_disabled, do_bit = 0, ad_reqd = 0, added_pheader = 0, have_pseudoheader = 0;
int checking_disabled, do_bit = 0, ad_reqd = 0, have_pseudoheader = 0;
struct blockdata *saved_question = NULL;
unsigned short qtype;
unsigned int gotname = 0;
@@ -2284,7 +2274,7 @@ unsigned char *tcp_request(int confd, time_t now,
while (1)
{
int stale = 0, ede = EDE_UNSET;
int cacheable = 1, stale = 0, ede = EDE_UNSET;
size_t m = 0;
unsigned int flags = 0;
#ifdef HAVE_AUTH
@@ -2329,6 +2319,7 @@ unsigned char *tcp_request(int confd, time_t now,
if (saved_question)
blockdata_free(saved_question);
size = add_edns0_config(header, size, ((unsigned char *) header) + 65536, &peer_addr, now, &cacheable);
saved_question = blockdata_alloc((char *)header, (size_t)size);
saved_size = size;
@@ -2395,7 +2386,7 @@ unsigned char *tcp_request(int confd, time_t now,
#endif
else
m = answer_request(header, ((char *) header) + 65536, (size_t)size,
dst_addr_4, netmask, now, ad_reqd, do_bit, &stale, &filtered);
dst_addr_4, netmask, now, ad_reqd, do_bit, !cacheable, &stale, &filtered);
}
}
@@ -2406,15 +2397,14 @@ unsigned char *tcp_request(int confd, time_t now,
{
struct server *master;
int start;
int cacheable, no_cache_dnssec = 0, cache_secure = 0, bogusanswer = 0;
int no_cache_dnssec = 0, cache_secure = 0, bogusanswer = 0;
blockdata_retrieve(saved_question, (size_t)saved_size, header);
size = saved_size;
/* save state of "cd" flag in query */
if ((checking_disabled = header->hb4 & HB4_CD))
no_cache_dnssec = 1;
checking_disabled = header->hb4 & HB4_CD;
if (lookup_domain(daemon->namebuff, gotname, &first, &last))
flags = is_local_answer(now, first, daemon->namebuff);
else
@@ -2437,8 +2427,6 @@ unsigned char *tcp_request(int confd, time_t now,
else
start = master->last_server;
size = add_edns0_config(header, size, ((unsigned char *) header) + 65536, &peer_addr, now, &cacheable);
#ifdef HAVE_DNSSEC
if (option_bool(OPT_DNSSEC_VALID) && (master->flags & SERV_DO_DNSSEC))
{
@@ -2451,11 +2439,6 @@ unsigned char *tcp_request(int confd, time_t now,
}
#endif
/* Check if we added a pheader on forwarding - may need to
strip it from the reply. */
if (!have_pseudoheader && find_pseudoheader(header, size, NULL, NULL, NULL, NULL))
added_pheader = 1;
/* Loop round available servers until we succeed in connecting to one. */
if ((m = tcp_talk(first, last, start, packet, size, have_mark, mark, &serv)) == 0)
ede = EDE_NETERR;
@@ -2472,7 +2455,9 @@ unsigned char *tcp_request(int confd, time_t now,
/* Clear this in case we don't call tcp_key_recurse() below */
memset(daemon->rr_status, 0, sizeof(*daemon->rr_status) * daemon->rr_status_sz);
if (!checking_disabled && (master->flags & SERV_DO_DNSSEC))
if (checking_disabled || (header->hb4 & HB4_CD))
no_cache_dnssec = 1;
else if (master->flags & SERV_DO_DNSSEC)
{
int keycount = daemon->limit[LIMIT_WORK]; /* Limit to number of DNSSEC questions, to catch loops and avoid filling cache. */
int validatecount = daemon->limit[LIMIT_CRYPTO];
@@ -2481,12 +2466,14 @@ unsigned char *tcp_request(int confd, time_t now,
char *result, *domain = "result";
union all_addr a;
a.log.ede = ede = errflags_to_ede(status);
ede = errflags_to_ede(status);
if (STAT_ISEQUAL(status, STAT_ABANDONED))
{
result = "ABANDONED";
status = STAT_BOGUS;
if (ede == EDE_UNSET)
ede = EDE_OTHER;
}
else
result = (STAT_ISEQUAL(status, STAT_SECURE) ? "SECURE" : (STAT_ISEQUAL(status, STAT_INSECURE) ? "INSECURE" : "BOGUS"));
@@ -2495,6 +2482,8 @@ unsigned char *tcp_request(int confd, time_t now,
cache_secure = 1;
else if (STAT_ISEQUAL(status, STAT_BOGUS))
{
if (ede == EDE_UNSET)
ede = EDE_DNSSEC_BOGUS;
no_cache_dnssec = 1;
bogusanswer = 1;
@@ -2502,6 +2491,7 @@ unsigned char *tcp_request(int confd, time_t now,
domain = daemon->namebuff;
}
a.log.ede = ede;
log_query(F_SECSTAT, domain, &a, result, 0);
if ((daemon->limit[LIMIT_CRYPTO] - validatecount) > (int)daemon->metrics[METRIC_CRYPTO_HWM])
@@ -2530,7 +2520,7 @@ unsigned char *tcp_request(int confd, time_t now,
m = process_reply(header, now, serv, (unsigned int)m,
option_bool(OPT_NO_REBIND) && !norebind, no_cache_dnssec, cache_secure, bogusanswer,
ad_reqd, do_bit, added_pheader, &peer_addr, ((unsigned char *)header) + 65536, ede);
ad_reqd, do_bit, !have_pseudoheader, &peer_addr, ((unsigned char *)header) + 65536, ede);
/* process_reply() adds pheader itself */
have_pseudoheader = 0;
+5 -1
View File
@@ -1567,7 +1567,7 @@ static int cache_validated(const struct crec *crecp)
/* return zero if we can't answer from cache, or packet size if we can */
size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
struct in_addr local_addr, struct in_addr local_netmask,
time_t now, int ad_reqd, int do_bit, int *stale, int *filtered)
time_t now, int ad_reqd, int do_bit, int no_cache, int *stale, int *filtered)
{
char *name = daemon->namebuff;
unsigned char *p, *ansp;
@@ -1582,6 +1582,10 @@ size_t answer_request(struct dns_header *header, char *limit, size_t qlen,
size_t len;
int rd_bit = (header->hb3 & HB3_RD);
int count = 255; /* catch loops */
/* Suppress cached answers of no_cache set. */
if (no_cache)
rd_bit = 0;
if (stale)
*stale = 0;
-3
View File
@@ -345,9 +345,6 @@ int expand_workspace(unsigned char ***wkspc, int *szp, int new)
if (old >= new+1)
return 1;
if (new >= 100)
return 0;
new += 5;
if (!(p = whine_realloc(*wkspc, new * sizeof(unsigned char *))))
+28 -23
View File
@@ -767,10 +767,10 @@ int retry_send(ssize_t rc)
/* rw = 0 -> write
rw = 1 -> read
rw = 2 -> read once
rw = 3 -> write once
rw = 2 -> write once
rw = 3 -> read once
"once" fail if all the data doesn't arrive/go in a single read/write.
"once" fails on EAGAIN, as this a timeout.
This indicates a timeout of a TCP socket.
*/
int read_write(int fd, unsigned char *packet, int size, int rw)
@@ -779,29 +779,34 @@ int read_write(int fd, unsigned char *packet, int size, int rw)
for (done = 0; done < size; done += n)
{
do {
if (rw & 1)
n = read(fd, &packet[done], (size_t)(size - done));
else
n = write(fd, &packet[done], (size_t)(size - done));
if (n == 0)
return 0;
if (n == -1 && errno == EINTR)
continue;
/* "once" variant */
if ((rw & 2) && n != size)
return 0;
} while (n == -1 && (errno == EINTR || errno == ENOMEM || errno == ENOBUFS ||
errno == EAGAIN || errno == EWOULDBLOCK));
if (rw & 1)
n = read(fd, &packet[done], (size_t)(size - done));
else
n = write(fd, &packet[done], (size_t)(size - done));
if (n == -1)
if (n == 0)
return 0;
if (n == -1)
{
n = 0; /* don't mess with counter when we loop. */
if (errno == EINTR || errno == ENOMEM || errno == ENOBUFS)
continue;
if (errno == EAGAIN || errno == EWOULDBLOCK)
{
/* "once" variant */
if (rw & 2)
return 0;
continue;
}
return 0;
}
}
return 1;
}