src/sbin/unwind/libunbound/services/outside_network.c

3932 lines
120 KiB
C

/*
* services/outside_network.c - implement sending of queries and wait answer.
*
* Copyright (c) 2007, NLnet Labs. All rights reserved.
*
* This software is open source.
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* Redistributions of source code must retain the above copyright notice,
* this list of conditions and the following disclaimer.
*
* Redistributions in binary form must reproduce the above copyright notice,
* this list of conditions and the following disclaimer in the documentation
* and/or other materials provided with the distribution.
*
* Neither the name of the NLNET LABS nor the names of its contributors may
* be used to endorse or promote products derived from this software without
* specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
* "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
* LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
* A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
* HOLDER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
* SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED
* TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR
* PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
/**
* \file
*
* This file has functions to send queries to authoritative servers and
* wait for the pending answer events.
*/
#include "config.h"
#include <ctype.h>
#ifdef HAVE_SYS_TYPES_H
# include <sys/types.h>
#endif
#include <sys/time.h>
#include "services/outside_network.h"
#include "services/listen_dnsport.h"
#include "services/cache/infra.h"
#include "iterator/iterator.h"
#include "util/data/msgparse.h"
#include "util/data/msgreply.h"
#include "util/data/msgencode.h"
#include "util/data/dname.h"
#include "util/netevent.h"
#include "util/log.h"
#include "util/net_help.h"
#include "util/random.h"
#include "util/fptr_wlist.h"
#include "util/edns.h"
#include "sldns/sbuffer.h"
#include "dnstap/dnstap.h"
#ifdef HAVE_OPENSSL_SSL_H
#include <openssl/ssl.h>
#endif
#ifdef HAVE_X509_VERIFY_PARAM_SET1_HOST
#include <openssl/x509v3.h>
#endif
#ifdef HAVE_NETDB_H
#include <netdb.h>
#endif
#include <fcntl.h>
/** number of times to retry making a random ID that is unique. */
#define MAX_ID_RETRY 1000
/** number of times to retry finding interface, port that can be opened. */
#define MAX_PORT_RETRY 10000
/** number of retries on outgoing UDP queries */
#define OUTBOUND_UDP_RETRY 1
/** initiate TCP transaction for serviced query */
static void serviced_tcp_initiate(struct serviced_query* sq, sldns_buffer* buff);
/** with a fd available, randomize and send UDP */
static int randomize_and_send_udp(struct pending* pend, sldns_buffer* packet,
int timeout);
/** select a DNS ID for a TCP stream */
static uint16_t tcp_select_id(struct outside_network* outnet,
struct reuse_tcp* reuse);
/** Perform serviced query UDP sending operation */
static int serviced_udp_send(struct serviced_query* sq, sldns_buffer* buff);
/** Send serviced query over TCP return false on initial failure */
static int serviced_tcp_send(struct serviced_query* sq, sldns_buffer* buff);
/** call the callbacks for a serviced query */
static void serviced_callbacks(struct serviced_query* sq, int error,
struct comm_point* c, struct comm_reply* rep);
int
pending_cmp(const void* key1, const void* key2)
{
struct pending *p1 = (struct pending*)key1;
struct pending *p2 = (struct pending*)key2;
if(p1->id < p2->id)
return -1;
if(p1->id > p2->id)
return 1;
log_assert(p1->id == p2->id);
return sockaddr_cmp(&p1->addr, p1->addrlen, &p2->addr, p2->addrlen);
}
int
serviced_cmp(const void* key1, const void* key2)
{
struct serviced_query* q1 = (struct serviced_query*)key1;
struct serviced_query* q2 = (struct serviced_query*)key2;
int r;
if(q1->qbuflen < q2->qbuflen)
return -1;
if(q1->qbuflen > q2->qbuflen)
return 1;
log_assert(q1->qbuflen == q2->qbuflen);
log_assert(q1->qbuflen >= 15 /* 10 header, root, type, class */);
/* alternate casing of qname is still the same query */
if((r = memcmp(q1->qbuf, q2->qbuf, 10)) != 0)
return r;
if((r = memcmp(q1->qbuf+q1->qbuflen-4, q2->qbuf+q2->qbuflen-4, 4)) != 0)
return r;
if(q1->dnssec != q2->dnssec) {
if(q1->dnssec < q2->dnssec)
return -1;
return 1;
}
if((r = query_dname_compare(q1->qbuf+10, q2->qbuf+10)) != 0)
return r;
if((r = edns_opt_list_compare(q1->opt_list, q2->opt_list)) != 0)
return r;
return sockaddr_cmp(&q1->addr, q1->addrlen, &q2->addr, q2->addrlen);
}
/** compare if the reuse element has the same address, port and same ssl-is
* used-for-it characteristic */
static int
reuse_cmp_addrportssl(const void* key1, const void* key2)
{
struct reuse_tcp* r1 = (struct reuse_tcp*)key1;
struct reuse_tcp* r2 = (struct reuse_tcp*)key2;
int r;
/* compare address and port */
r = sockaddr_cmp(&r1->addr, r1->addrlen, &r2->addr, r2->addrlen);
if(r != 0)
return r;
/* compare if SSL-enabled */
if(r1->is_ssl && !r2->is_ssl)
return 1;
if(!r1->is_ssl && r2->is_ssl)
return -1;
return 0;
}
int
reuse_cmp(const void* key1, const void* key2)
{
int r;
r = reuse_cmp_addrportssl(key1, key2);
if(r != 0)
return r;
/* compare ptr value */
if(key1 < key2) return -1;
if(key1 > key2) return 1;
return 0;
}
int reuse_id_cmp(const void* key1, const void* key2)
{
struct waiting_tcp* w1 = (struct waiting_tcp*)key1;
struct waiting_tcp* w2 = (struct waiting_tcp*)key2;
if(w1->id < w2->id)
return -1;
if(w1->id > w2->id)
return 1;
return 0;
}
/** delete waiting_tcp entry. Does not unlink from waiting list.
* @param w: to delete.
*/
static void
waiting_tcp_delete(struct waiting_tcp* w)
{
if(!w) return;
if(w->timer)
comm_timer_delete(w->timer);
free(w);
}
/**
* Pick random outgoing-interface of that family, and bind it.
* port set to 0 so OS picks a port number for us.
* if it is the ANY address, do not bind.
* @param pend: pending tcp structure, for storing the local address choice.
* @param w: tcp structure with destination address.
* @param s: socket fd.
* @return false on error, socket closed.
*/
static int
pick_outgoing_tcp(struct pending_tcp* pend, struct waiting_tcp* w, int s)
{
struct port_if* pi = NULL;
int num;
pend->pi = NULL;
#ifdef INET6
if(addr_is_ip6(&w->addr, w->addrlen))
num = w->outnet->num_ip6;
else
#endif
num = w->outnet->num_ip4;
if(num == 0) {
log_err("no TCP outgoing interfaces of family");
log_addr(VERB_OPS, "for addr", &w->addr, w->addrlen);
sock_close(s);
return 0;
}
#ifdef INET6
if(addr_is_ip6(&w->addr, w->addrlen))
pi = &w->outnet->ip6_ifs[ub_random_max(w->outnet->rnd, num)];
else
#endif
pi = &w->outnet->ip4_ifs[ub_random_max(w->outnet->rnd, num)];
log_assert(pi);
pend->pi = pi;
if(addr_is_any(&pi->addr, pi->addrlen)) {
/* binding to the ANY interface is for listening sockets */
return 1;
}
/* set port to 0 */
if(addr_is_ip6(&pi->addr, pi->addrlen))
((struct sockaddr_in6*)&pi->addr)->sin6_port = 0;
else ((struct sockaddr_in*)&pi->addr)->sin_port = 0;
if(bind(s, (struct sockaddr*)&pi->addr, pi->addrlen) != 0) {
#ifndef USE_WINSOCK
#ifdef EADDRNOTAVAIL
if(!(verbosity < 4 && errno == EADDRNOTAVAIL))
#endif
#else /* USE_WINSOCK */
if(!(verbosity < 4 && WSAGetLastError() == WSAEADDRNOTAVAIL))
#endif
log_err("outgoing tcp: bind: %s", sock_strerror(errno));
sock_close(s);
return 0;
}
log_addr(VERB_ALGO, "tcp bound to src", &pi->addr, pi->addrlen);
return 1;
}
/** get TCP file descriptor for address, returns -1 on failure,
* tcp_mss is 0 or maxseg size to set for TCP packets. */
int
outnet_get_tcp_fd(struct sockaddr_storage* addr, socklen_t addrlen, int tcp_mss, int dscp)
{
int s;
int af;
char* err;
#if defined(SO_REUSEADDR) || defined(IP_BIND_ADDRESS_NO_PORT)
int on = 1;
#endif
#ifdef INET6
if(addr_is_ip6(addr, addrlen)){
s = socket(PF_INET6, SOCK_STREAM, IPPROTO_TCP);
af = AF_INET6;
} else {
#else
{
#endif
af = AF_INET;
s = socket(PF_INET, SOCK_STREAM, IPPROTO_TCP);
}
if(s == -1) {
log_err_addr("outgoing tcp: socket", sock_strerror(errno),
addr, addrlen);
return -1;
}
#ifdef SO_REUSEADDR
if(setsockopt(s, SOL_SOCKET, SO_REUSEADDR, (void*)&on,
(socklen_t)sizeof(on)) < 0) {
verbose(VERB_ALGO, "outgoing tcp:"
" setsockopt(.. SO_REUSEADDR ..) failed");
}
#endif
err = set_ip_dscp(s, af, dscp);
if(err != NULL) {
verbose(VERB_ALGO, "outgoing tcp:"
"error setting IP DiffServ codepoint on socket");
}
if(tcp_mss > 0) {
#if defined(IPPROTO_TCP) && defined(TCP_MAXSEG)
if(setsockopt(s, IPPROTO_TCP, TCP_MAXSEG,
(void*)&tcp_mss, (socklen_t)sizeof(tcp_mss)) < 0) {
verbose(VERB_ALGO, "outgoing tcp:"
" setsockopt(.. TCP_MAXSEG ..) failed");
}
#else
verbose(VERB_ALGO, "outgoing tcp:"
" setsockopt(TCP_MAXSEG) unsupported");
#endif /* defined(IPPROTO_TCP) && defined(TCP_MAXSEG) */
}
#ifdef IP_BIND_ADDRESS_NO_PORT
if(setsockopt(s, IPPROTO_IP, IP_BIND_ADDRESS_NO_PORT, (void*)&on,
(socklen_t)sizeof(on)) < 0) {
verbose(VERB_ALGO, "outgoing tcp:"
" setsockopt(.. IP_BIND_ADDRESS_NO_PORT ..) failed");
}
#endif /* IP_BIND_ADDRESS_NO_PORT */
return s;
}
/** connect tcp connection to addr, 0 on failure */
int
outnet_tcp_connect(int s, struct sockaddr_storage* addr, socklen_t addrlen)
{
if(connect(s, (struct sockaddr*)addr, addrlen) == -1) {
#ifndef USE_WINSOCK
#ifdef EINPROGRESS
if(errno != EINPROGRESS) {
#endif
if(tcp_connect_errno_needs_log(
(struct sockaddr*)addr, addrlen))
log_err_addr("outgoing tcp: connect",
strerror(errno), addr, addrlen);
close(s);
return 0;
#ifdef EINPROGRESS
}
#endif
#else /* USE_WINSOCK */
if(WSAGetLastError() != WSAEINPROGRESS &&
WSAGetLastError() != WSAEWOULDBLOCK) {
closesocket(s);
return 0;
}
#endif
}
return 1;
}
/** log reuse item addr and ptr with message */
static void
log_reuse_tcp(enum verbosity_value v, const char* msg, struct reuse_tcp* reuse)
{
uint16_t port;
char addrbuf[128];
if(verbosity < v) return;
if(!reuse || !reuse->pending || !reuse->pending->c)
return;
addr_to_str(&reuse->addr, reuse->addrlen, addrbuf, sizeof(addrbuf));
port = ntohs(((struct sockaddr_in*)&reuse->addr)->sin_port);
verbose(v, "%s %s#%u fd %d", msg, addrbuf, (unsigned)port,
reuse->pending->c->fd);
}
/** pop the first element from the writewait list */
struct waiting_tcp*
reuse_write_wait_pop(struct reuse_tcp* reuse)
{
struct waiting_tcp* w = reuse->write_wait_first;
if(!w)
return NULL;
log_assert(w->write_wait_queued);
log_assert(!w->write_wait_prev);
reuse->write_wait_first = w->write_wait_next;
if(w->write_wait_next)
w->write_wait_next->write_wait_prev = NULL;
else reuse->write_wait_last = NULL;
w->write_wait_queued = 0;
w->write_wait_next = NULL;
w->write_wait_prev = NULL;
return w;
}
/** remove the element from the writewait list */
void
reuse_write_wait_remove(struct reuse_tcp* reuse, struct waiting_tcp* w)
{
log_assert(w);
log_assert(w->write_wait_queued);
if(!w)
return;
if(!w->write_wait_queued)
return;
if(w->write_wait_prev)
w->write_wait_prev->write_wait_next = w->write_wait_next;
else reuse->write_wait_first = w->write_wait_next;
log_assert(!w->write_wait_prev ||
w->write_wait_prev->write_wait_next != w->write_wait_prev);
if(w->write_wait_next)
w->write_wait_next->write_wait_prev = w->write_wait_prev;
else reuse->write_wait_last = w->write_wait_prev;
log_assert(!w->write_wait_next
|| w->write_wait_next->write_wait_prev != w->write_wait_next);
w->write_wait_queued = 0;
w->write_wait_next = NULL;
w->write_wait_prev = NULL;
}
/** push the element after the last on the writewait list */
void
reuse_write_wait_push_back(struct reuse_tcp* reuse, struct waiting_tcp* w)
{
if(!w) return;
log_assert(!w->write_wait_queued);
if(reuse->write_wait_last) {
reuse->write_wait_last->write_wait_next = w;
log_assert(reuse->write_wait_last->write_wait_next !=
reuse->write_wait_last);
w->write_wait_prev = reuse->write_wait_last;
} else {
reuse->write_wait_first = w;
w->write_wait_prev = NULL;
}
w->write_wait_next = NULL;
reuse->write_wait_last = w;
w->write_wait_queued = 1;
}
/** insert element in tree by id */
void
reuse_tree_by_id_insert(struct reuse_tcp* reuse, struct waiting_tcp* w)
{
#ifdef UNBOUND_DEBUG
rbnode_type* added;
#endif
log_assert(w->id_node.key == NULL);
w->id_node.key = w;
#ifdef UNBOUND_DEBUG
added =
#else
(void)
#endif
rbtree_insert(&reuse->tree_by_id, &w->id_node);
log_assert(added); /* should have been added */
}
/** find element in tree by id */
struct waiting_tcp*
reuse_tcp_by_id_find(struct reuse_tcp* reuse, uint16_t id)
{
struct waiting_tcp key_w;
rbnode_type* n;
memset(&key_w, 0, sizeof(key_w));
key_w.id_node.key = &key_w;
key_w.id = id;
n = rbtree_search(&reuse->tree_by_id, &key_w);
if(!n) return NULL;
return (struct waiting_tcp*)n->key;
}
/** return ID value of rbnode in tree_by_id */
static uint16_t
tree_by_id_get_id(rbnode_type* node)
{
struct waiting_tcp* w = (struct waiting_tcp*)node->key;
return w->id;
}
/** insert into reuse tcp tree and LRU, false on failure (duplicate) */
int
reuse_tcp_insert(struct outside_network* outnet, struct pending_tcp* pend_tcp)
{
log_reuse_tcp(VERB_CLIENT, "reuse_tcp_insert", &pend_tcp->reuse);
if(pend_tcp->reuse.item_on_lru_list) {
if(!pend_tcp->reuse.node.key)
log_err("internal error: reuse_tcp_insert: "
"in lru list without key");
return 1;
}
pend_tcp->reuse.node.key = &pend_tcp->reuse;
pend_tcp->reuse.pending = pend_tcp;
if(!rbtree_insert(&outnet->tcp_reuse, &pend_tcp->reuse.node)) {
/* We are not in the LRU list but we are already in the
* tcp_reuse tree, strange.
* Continue to add ourselves to the LRU list. */
log_err("internal error: reuse_tcp_insert: in lru list but "
"not in the tree");
}
/* insert into LRU, first is newest */
pend_tcp->reuse.lru_prev = NULL;
if(outnet->tcp_reuse_first) {
pend_tcp->reuse.lru_next = outnet->tcp_reuse_first;
log_assert(pend_tcp->reuse.lru_next != &pend_tcp->reuse);
outnet->tcp_reuse_first->lru_prev = &pend_tcp->reuse;
log_assert(outnet->tcp_reuse_first->lru_prev !=
outnet->tcp_reuse_first);
} else {
pend_tcp->reuse.lru_next = NULL;
outnet->tcp_reuse_last = &pend_tcp->reuse;
}
outnet->tcp_reuse_first = &pend_tcp->reuse;
pend_tcp->reuse.item_on_lru_list = 1;
log_assert((!outnet->tcp_reuse_first && !outnet->tcp_reuse_last) ||
(outnet->tcp_reuse_first && outnet->tcp_reuse_last));
log_assert(outnet->tcp_reuse_first != outnet->tcp_reuse_first->lru_next &&
outnet->tcp_reuse_first != outnet->tcp_reuse_first->lru_prev);
log_assert(outnet->tcp_reuse_last != outnet->tcp_reuse_last->lru_next &&
outnet->tcp_reuse_last != outnet->tcp_reuse_last->lru_prev);
return 1;
}
/** find reuse tcp stream to destination for query, or NULL if none */
static struct reuse_tcp*
reuse_tcp_find(struct outside_network* outnet, struct sockaddr_storage* addr,
socklen_t addrlen, int use_ssl)
{
struct waiting_tcp key_w;
struct pending_tcp key_p;
struct comm_point c;
rbnode_type* result = NULL, *prev;
verbose(VERB_CLIENT, "reuse_tcp_find");
memset(&key_w, 0, sizeof(key_w));
memset(&key_p, 0, sizeof(key_p));
memset(&c, 0, sizeof(c));
key_p.query = &key_w;
key_p.c = &c;
key_p.reuse.pending = &key_p;
key_p.reuse.node.key = &key_p.reuse;
if(use_ssl)
key_p.reuse.is_ssl = 1;
if(addrlen > (socklen_t)sizeof(key_p.reuse.addr))
return NULL;
memmove(&key_p.reuse.addr, addr, addrlen);
key_p.reuse.addrlen = addrlen;
verbose(VERB_CLIENT, "reuse_tcp_find: num reuse streams %u",
(unsigned)outnet->tcp_reuse.count);
if(outnet->tcp_reuse.root == NULL ||
outnet->tcp_reuse.root == RBTREE_NULL)
return NULL;
if(rbtree_find_less_equal(&outnet->tcp_reuse, &key_p.reuse,
&result)) {
/* exact match */
/* but the key is on stack, and ptr is compared, impossible */
log_assert(&key_p.reuse != (struct reuse_tcp*)result);
log_assert(&key_p != ((struct reuse_tcp*)result)->pending);
}
/* It is possible that we search for something before the first element
* in the tree. Replace a null pointer with the first element.
*/
if (!result) {
verbose(VERB_CLIENT, "reuse_tcp_find: taking first");
result = rbtree_first(&outnet->tcp_reuse);
}
/* not found, return null */
if(!result || result == RBTREE_NULL)
return NULL;
/* It is possible that we got the previous address, but that the
* address we are looking for is in the tree. If the address we got
* is less than the address we are looking, then take the next entry.
*/
if (reuse_cmp_addrportssl(result->key, &key_p.reuse) < 0) {
verbose(VERB_CLIENT, "reuse_tcp_find: key too low");
result = rbtree_next(result);
}
verbose(VERB_CLIENT, "reuse_tcp_find check inexact match");
/* inexact match, find one of possibly several connections to the
* same destination address, with the correct port, ssl, and
* also less than max number of open queries, or else, fail to open
* a new one */
/* rewind to start of sequence of same address,port,ssl */
prev = rbtree_previous(result);
while(prev && prev != RBTREE_NULL &&
reuse_cmp_addrportssl(prev->key, &key_p.reuse) == 0) {
result = prev;
prev = rbtree_previous(result);
}
/* loop to find first one that has correct characteristics */
while(result && result != RBTREE_NULL &&
reuse_cmp_addrportssl(result->key, &key_p.reuse) == 0) {
if(((struct reuse_tcp*)result)->tree_by_id.count <
outnet->max_reuse_tcp_queries) {
/* same address, port, ssl-yes-or-no, and has
* space for another query */
return (struct reuse_tcp*)result;
}
result = rbtree_next(result);
}
return NULL;
}
/** use the buffer to setup writing the query */
static void
outnet_tcp_take_query_setup(int s, struct pending_tcp* pend,
struct waiting_tcp* w)
{
struct timeval tv;
verbose(VERB_CLIENT, "outnet_tcp_take_query_setup: setup packet to write "
"len %d timeout %d msec",
(int)w->pkt_len, w->timeout);
pend->c->tcp_write_pkt = w->pkt;
pend->c->tcp_write_pkt_len = w->pkt_len;
pend->c->tcp_write_and_read = 1;
pend->c->tcp_write_byte_count = 0;
pend->c->tcp_is_reading = 0;
comm_point_start_listening(pend->c, s, -1);
/* set timer on the waiting_tcp entry, this is the write timeout
* for the written packet. The timer on pend->c is the timer
* for when there is no written packet and we have readtimeouts */
#ifndef S_SPLINT_S
tv.tv_sec = w->timeout/1000;
tv.tv_usec = (w->timeout%1000)*1000;
#endif
/* if the waiting_tcp was previously waiting for a buffer in the
* outside_network.tcpwaitlist, then the timer is reset now that
* we start writing it */
comm_timer_set(w->timer, &tv);
}
/** use next free buffer to service a tcp query */
static int
outnet_tcp_take_into_use(struct waiting_tcp* w)
{
struct pending_tcp* pend = w->outnet->tcp_free;
int s;
log_assert(pend);
log_assert(w->pkt);
log_assert(w->pkt_len > 0);
log_assert(w->addrlen > 0);
pend->c->tcp_do_toggle_rw = 0;
pend->c->tcp_do_close = 0;
/* Consistency check, if we have ssl_upstream but no sslctx, then
* log an error and return failure.
*/
if (w->ssl_upstream && !w->outnet->sslctx) {
log_err("SSL upstream requested but no SSL context");
return 0;
}
/* open socket */
s = outnet_get_tcp_fd(&w->addr, w->addrlen, w->outnet->tcp_mss, w->outnet->ip_dscp);
if(s == -1)
return 0;
if(!pick_outgoing_tcp(pend, w, s))
return 0;
fd_set_nonblock(s);
#ifdef USE_OSX_MSG_FASTOPEN
/* API for fast open is different here. We use a connectx() function and
then writes can happen as normal even using SSL.*/
/* connectx requires that the len be set in the sockaddr struct*/
struct sockaddr_in *addr_in = (struct sockaddr_in *)&w->addr;
addr_in->sin_len = w->addrlen;
sa_endpoints_t endpoints;
endpoints.sae_srcif = 0;
endpoints.sae_srcaddr = NULL;
endpoints.sae_srcaddrlen = 0;
endpoints.sae_dstaddr = (struct sockaddr *)&w->addr;
endpoints.sae_dstaddrlen = w->addrlen;
if (connectx(s, &endpoints, SAE_ASSOCID_ANY,
CONNECT_DATA_IDEMPOTENT | CONNECT_RESUME_ON_READ_WRITE,
NULL, 0, NULL, NULL) == -1) {
/* if fails, failover to connect for OSX 10.10 */
#ifdef EINPROGRESS
if(errno != EINPROGRESS) {
#else
if(1) {
#endif
if(connect(s, (struct sockaddr*)&w->addr, w->addrlen) == -1) {
#else /* USE_OSX_MSG_FASTOPEN*/
#ifdef USE_MSG_FASTOPEN
pend->c->tcp_do_fastopen = 1;
/* Only do TFO for TCP in which case no connect() is required here.
Don't combine client TFO with SSL, since OpenSSL can't
currently support doing a handshake on fd that already isn't connected*/
if (w->outnet->sslctx && w->ssl_upstream) {
if(connect(s, (struct sockaddr*)&w->addr, w->addrlen) == -1) {
#else /* USE_MSG_FASTOPEN*/
if(connect(s, (struct sockaddr*)&w->addr, w->addrlen) == -1) {
#endif /* USE_MSG_FASTOPEN*/
#endif /* USE_OSX_MSG_FASTOPEN*/
#ifndef USE_WINSOCK
#ifdef EINPROGRESS
if(errno != EINPROGRESS) {
#else
if(1) {
#endif
if(tcp_connect_errno_needs_log(
(struct sockaddr*)&w->addr, w->addrlen))
log_err_addr("outgoing tcp: connect",
strerror(errno), &w->addr, w->addrlen);
close(s);
#else /* USE_WINSOCK */
if(WSAGetLastError() != WSAEINPROGRESS &&
WSAGetLastError() != WSAEWOULDBLOCK) {
closesocket(s);
#endif
return 0;
}
}
#ifdef USE_MSG_FASTOPEN
}
#endif /* USE_MSG_FASTOPEN */
#ifdef USE_OSX_MSG_FASTOPEN
}
}
#endif /* USE_OSX_MSG_FASTOPEN */
if(w->outnet->sslctx && w->ssl_upstream) {
pend->c->ssl = outgoing_ssl_fd(w->outnet->sslctx, s);
if(!pend->c->ssl) {
pend->c->fd = s;
comm_point_close(pend->c);
return 0;
}
verbose(VERB_ALGO, "the query is using TLS encryption, for %s",
(w->tls_auth_name?w->tls_auth_name:"an unauthenticated connection"));
#ifdef USE_WINSOCK
comm_point_tcp_win_bio_cb(pend->c, pend->c->ssl);
#endif
pend->c->ssl_shake_state = comm_ssl_shake_write;
if(!set_auth_name_on_ssl(pend->c->ssl, w->tls_auth_name,
w->outnet->tls_use_sni)) {
pend->c->fd = s;
#ifdef HAVE_SSL
SSL_free(pend->c->ssl);
#endif
pend->c->ssl = NULL;
comm_point_close(pend->c);
return 0;
}
}
w->next_waiting = (void*)pend;
w->outnet->num_tcp_outgoing++;
w->outnet->tcp_free = pend->next_free;
pend->next_free = NULL;
pend->query = w;
pend->reuse.outnet = w->outnet;
pend->c->repinfo.remote_addrlen = w->addrlen;
pend->c->tcp_more_read_again = &pend->reuse.cp_more_read_again;
pend->c->tcp_more_write_again = &pend->reuse.cp_more_write_again;
pend->reuse.cp_more_read_again = 0;
pend->reuse.cp_more_write_again = 0;
memcpy(&pend->c->repinfo.remote_addr, &w->addr, w->addrlen);
pend->reuse.pending = pend;
/* Remove from tree in case the is_ssl will be different and causes the
* identity of the reuse_tcp to change; could result in nodes not being
* deleted from the tree (because the new identity does not match the
* previous node) but their ->key would be changed to NULL. */
if(pend->reuse.node.key)
reuse_tcp_remove_tree_list(w->outnet, &pend->reuse);
if(pend->c->ssl)
pend->reuse.is_ssl = 1;
else pend->reuse.is_ssl = 0;
/* insert in reuse by address tree if not already inserted there */
(void)reuse_tcp_insert(w->outnet, pend);
reuse_tree_by_id_insert(&pend->reuse, w);
outnet_tcp_take_query_setup(s, pend, w);
return 1;
}
/** Touch the lru of a reuse_tcp element, it is in use.
* This moves it to the front of the list, where it is not likely to
* be closed. Items at the back of the list are closed to make space. */
void
reuse_tcp_lru_touch(struct outside_network* outnet, struct reuse_tcp* reuse)
{
if(!reuse->item_on_lru_list) {
log_err("internal error: we need to touch the lru_list but item not in list");
return; /* not on the list, no lru to modify */
}
log_assert(reuse->lru_prev ||
(!reuse->lru_prev && outnet->tcp_reuse_first == reuse));
if(!reuse->lru_prev)
return; /* already first in the list */
/* remove at current position */
/* since it is not first, there is a previous element */
reuse->lru_prev->lru_next = reuse->lru_next;
log_assert(reuse->lru_prev->lru_next != reuse->lru_prev);
if(reuse->lru_next)
reuse->lru_next->lru_prev = reuse->lru_prev;
else outnet->tcp_reuse_last = reuse->lru_prev;
log_assert(!reuse->lru_next || reuse->lru_next->lru_prev != reuse->lru_next);
log_assert(outnet->tcp_reuse_last != outnet->tcp_reuse_last->lru_next &&
outnet->tcp_reuse_last != outnet->tcp_reuse_last->lru_prev);
/* insert at the front */
reuse->lru_prev = NULL;
reuse->lru_next = outnet->tcp_reuse_first;
if(outnet->tcp_reuse_first) {
outnet->tcp_reuse_first->lru_prev = reuse;
}
log_assert(reuse->lru_next != reuse);
/* since it is not first, it is not the only element and
* lru_next is thus not NULL and thus reuse is now not the last in
* the list, so outnet->tcp_reuse_last does not need to be modified */
outnet->tcp_reuse_first = reuse;
log_assert(outnet->tcp_reuse_first != outnet->tcp_reuse_first->lru_next &&
outnet->tcp_reuse_first != outnet->tcp_reuse_first->lru_prev);
log_assert((!outnet->tcp_reuse_first && !outnet->tcp_reuse_last) ||
(outnet->tcp_reuse_first && outnet->tcp_reuse_last));
}
/** Snip the last reuse_tcp element off of the LRU list */
struct reuse_tcp*
reuse_tcp_lru_snip(struct outside_network* outnet)
{
struct reuse_tcp* reuse = outnet->tcp_reuse_last;
if(!reuse) return NULL;
/* snip off of LRU */
log_assert(reuse->lru_next == NULL);
if(reuse->lru_prev) {
outnet->tcp_reuse_last = reuse->lru_prev;
reuse->lru_prev->lru_next = NULL;
} else {
outnet->tcp_reuse_last = NULL;
outnet->tcp_reuse_first = NULL;
}
log_assert((!outnet->tcp_reuse_first && !outnet->tcp_reuse_last) ||
(outnet->tcp_reuse_first && outnet->tcp_reuse_last));
reuse->item_on_lru_list = 0;
reuse->lru_next = NULL;
reuse->lru_prev = NULL;
return reuse;
}
/** remove waiting tcp from the outnet waiting list */
void
outnet_waiting_tcp_list_remove(struct outside_network* outnet, struct waiting_tcp* w)
{
struct waiting_tcp* p = outnet->tcp_wait_first, *prev = NULL;
w->on_tcp_waiting_list = 0;
while(p) {
if(p == w) {
/* remove w */
if(prev)
prev->next_waiting = w->next_waiting;
else outnet->tcp_wait_first = w->next_waiting;
if(outnet->tcp_wait_last == w)
outnet->tcp_wait_last = prev;
w->next_waiting = NULL;
return;
}
prev = p;
p = p->next_waiting;
}
/* outnet_waiting_tcp_list_remove is currently called only with items
* that are already in the waiting list. */
log_assert(0);
}
/** pop the first waiting tcp from the outnet waiting list */
struct waiting_tcp*
outnet_waiting_tcp_list_pop(struct outside_network* outnet)
{
struct waiting_tcp* w = outnet->tcp_wait_first;
if(!outnet->tcp_wait_first) return NULL;
log_assert(w->on_tcp_waiting_list);
outnet->tcp_wait_first = w->next_waiting;
if(outnet->tcp_wait_last == w)
outnet->tcp_wait_last = NULL;
w->on_tcp_waiting_list = 0;
w->next_waiting = NULL;
return w;
}
/** add waiting_tcp element to the outnet tcp waiting list */
void
outnet_waiting_tcp_list_add(struct outside_network* outnet,
struct waiting_tcp* w, int set_timer)
{
struct timeval tv;
log_assert(!w->on_tcp_waiting_list);
if(w->on_tcp_waiting_list)
return;
w->next_waiting = NULL;
if(outnet->tcp_wait_last)
outnet->tcp_wait_last->next_waiting = w;
else outnet->tcp_wait_first = w;
outnet->tcp_wait_last = w;
w->on_tcp_waiting_list = 1;
if(set_timer) {
#ifndef S_SPLINT_S
tv.tv_sec = w->timeout/1000;
tv.tv_usec = (w->timeout%1000)*1000;
#endif
comm_timer_set(w->timer, &tv);
}
}
/** add waiting_tcp element as first to the outnet tcp waiting list */
void
outnet_waiting_tcp_list_add_first(struct outside_network* outnet,
struct waiting_tcp* w, int reset_timer)
{
struct timeval tv;
log_assert(!w->on_tcp_waiting_list);
if(w->on_tcp_waiting_list)
return;
w->next_waiting = outnet->tcp_wait_first;
log_assert(w->next_waiting != w);
if(!outnet->tcp_wait_last)
outnet->tcp_wait_last = w;
outnet->tcp_wait_first = w;
w->on_tcp_waiting_list = 1;
if(reset_timer) {
#ifndef S_SPLINT_S
tv.tv_sec = w->timeout/1000;
tv.tv_usec = (w->timeout%1000)*1000;
#endif
comm_timer_set(w->timer, &tv);
}
log_assert(
(!outnet->tcp_reuse_first && !outnet->tcp_reuse_last) ||
(outnet->tcp_reuse_first && outnet->tcp_reuse_last));
}
/** call callback on waiting_tcp, if not NULL */
static void
waiting_tcp_callback(struct waiting_tcp* w, struct comm_point* c, int error,
struct comm_reply* reply_info)
{
if(w && w->cb) {
fptr_ok(fptr_whitelist_pending_tcp(w->cb));
(void)(*w->cb)(c, w->cb_arg, error, reply_info);
}
}
/** see if buffers can be used to service TCP queries */
static void
use_free_buffer(struct outside_network* outnet)
{
struct waiting_tcp* w;
while(outnet->tcp_wait_first && !outnet->want_to_quit) {
#ifdef USE_DNSTAP
struct pending_tcp* pend_tcp = NULL;
#endif
struct reuse_tcp* reuse = NULL;
w = outnet_waiting_tcp_list_pop(outnet);
log_assert(
(!outnet->tcp_reuse_first && !outnet->tcp_reuse_last) ||
(outnet->tcp_reuse_first && outnet->tcp_reuse_last));
reuse = reuse_tcp_find(outnet, &w->addr, w->addrlen,
w->ssl_upstream);
/* re-select an ID when moving to a new TCP buffer */
w->id = tcp_select_id(outnet, reuse);
LDNS_ID_SET(w->pkt, w->id);
if(reuse) {
log_reuse_tcp(VERB_CLIENT, "use free buffer for waiting tcp: "
"found reuse", reuse);
#ifdef USE_DNSTAP
pend_tcp = reuse->pending;
#endif
reuse_tcp_lru_touch(outnet, reuse);
comm_timer_disable(w->timer);
w->next_waiting = (void*)reuse->pending;
reuse_tree_by_id_insert(reuse, w);
if(reuse->pending->query) {
/* on the write wait list */
reuse_write_wait_push_back(reuse, w);
} else {
/* write straight away */
/* stop the timer on read of the fd */
comm_point_stop_listening(reuse->pending->c);
reuse->pending->query = w;
outnet_tcp_take_query_setup(
reuse->pending->c->fd, reuse->pending,
w);
}
} else if(outnet->tcp_free) {
struct pending_tcp* pend = w->outnet->tcp_free;
rbtree_init(&pend->reuse.tree_by_id, reuse_id_cmp);
pend->reuse.pending = pend;
memcpy(&pend->reuse.addr, &w->addr, w->addrlen);
pend->reuse.addrlen = w->addrlen;
if(!outnet_tcp_take_into_use(w)) {
waiting_tcp_callback(w, NULL, NETEVENT_CLOSED,
NULL);
waiting_tcp_delete(w);
#ifdef USE_DNSTAP
w = NULL;
#endif
}
#ifdef USE_DNSTAP
pend_tcp = pend;
#endif
} else {
/* no reuse and no free buffer, put back at the start */
outnet_waiting_tcp_list_add_first(outnet, w, 0);
break;
}
#ifdef USE_DNSTAP
if(outnet->dtenv && pend_tcp && w && w->sq &&
(outnet->dtenv->log_resolver_query_messages ||
outnet->dtenv->log_forwarder_query_messages)) {
sldns_buffer tmp;
sldns_buffer_init_frm_data(&tmp, w->pkt, w->pkt_len);
dt_msg_send_outside_query(outnet->dtenv, &w->sq->addr,
&pend_tcp->pi->addr, comm_tcp, NULL, w->sq->zone,
w->sq->zonelen, &tmp);
}
#endif
}
}
/** delete element from tree by id */
static void
reuse_tree_by_id_delete(struct reuse_tcp* reuse, struct waiting_tcp* w)
{
#ifdef UNBOUND_DEBUG
rbnode_type* rem;
#endif
log_assert(w->id_node.key != NULL);
#ifdef UNBOUND_DEBUG
rem =
#else
(void)
#endif
rbtree_delete(&reuse->tree_by_id, w);
log_assert(rem); /* should have been there */
w->id_node.key = NULL;
}
/** move writewait list to go for another connection. */
static void
reuse_move_writewait_away(struct outside_network* outnet,
struct pending_tcp* pend)
{
/* the writewait list has not been written yet, so if the
* stream was closed, they have not actually been failed, only
* the queries written. Other queries can get written to another
* stream. For upstreams that do not support multiple queries
* and answers, the stream can get closed, and then the queries
* can get written on a new socket */
struct waiting_tcp* w;
if(pend->query && pend->query->error_count == 0 &&
pend->c->tcp_write_pkt == pend->query->pkt &&
pend->c->tcp_write_pkt_len == pend->query->pkt_len) {
/* since the current query is not written, it can also
* move to a free buffer */
if(verbosity >= VERB_CLIENT && pend->query->pkt_len > 12+2+2 &&
LDNS_QDCOUNT(pend->query->pkt) > 0 &&
dname_valid(pend->query->pkt+12, pend->query->pkt_len-12)) {
char buf[LDNS_MAX_DOMAINLEN+1];
dname_str(pend->query->pkt+12, buf);
verbose(VERB_CLIENT, "reuse_move_writewait_away current %s %d bytes were written",
buf, (int)pend->c->tcp_write_byte_count);
}
pend->c->tcp_write_pkt = NULL;
pend->c->tcp_write_pkt_len = 0;
pend->c->tcp_write_and_read = 0;
pend->reuse.cp_more_read_again = 0;
pend->reuse.cp_more_write_again = 0;
pend->c->tcp_is_reading = 1;
w = pend->query;
pend->query = NULL;
/* increase error count, so that if the next socket fails too
* the server selection is run again with this query failed
* and it can select a different server (if possible), or
* fail the query */
w->error_count ++;
reuse_tree_by_id_delete(&pend->reuse, w);
outnet_waiting_tcp_list_add(outnet, w, 1);
}
while((w = reuse_write_wait_pop(&pend->reuse)) != NULL) {
if(verbosity >= VERB_CLIENT && w->pkt_len > 12+2+2 &&
LDNS_QDCOUNT(w->pkt) > 0 &&
dname_valid(w->pkt+12, w->pkt_len-12)) {
char buf[LDNS_MAX_DOMAINLEN+1];
dname_str(w->pkt+12, buf);
verbose(VERB_CLIENT, "reuse_move_writewait_away item %s", buf);
}
reuse_tree_by_id_delete(&pend->reuse, w);
outnet_waiting_tcp_list_add(outnet, w, 1);
}
}
/** remove reused element from tree and lru list */
void
reuse_tcp_remove_tree_list(struct outside_network* outnet,
struct reuse_tcp* reuse)
{
verbose(VERB_CLIENT, "reuse_tcp_remove_tree_list");
if(reuse->node.key) {
/* delete it from reuse tree */
if(!rbtree_delete(&outnet->tcp_reuse, reuse)) {
/* should not be possible, it should be there */
char buf[256];
addr_to_str(&reuse->addr, reuse->addrlen, buf,
sizeof(buf));
log_err("reuse tcp delete: node not present, internal error, %s ssl %d lru %d", buf, reuse->is_ssl, reuse->item_on_lru_list);
}
reuse->node.key = NULL;
/* defend against loops on broken tree by zeroing the
* rbnode structure */
memset(&reuse->node, 0, sizeof(reuse->node));
}
/* delete from reuse list */
if(reuse->item_on_lru_list) {
if(reuse->lru_prev) {
/* assert that members of the lru list are waiting
* and thus have a pending pointer to the struct */
log_assert(reuse->lru_prev->pending);
reuse->lru_prev->lru_next = reuse->lru_next;
log_assert(reuse->lru_prev->lru_next != reuse->lru_prev);
} else {
log_assert(!reuse->lru_next || reuse->lru_next->pending);
outnet->tcp_reuse_first = reuse->lru_next;
log_assert(!outnet->tcp_reuse_first ||
(outnet->tcp_reuse_first !=
outnet->tcp_reuse_first->lru_next &&
outnet->tcp_reuse_first !=
outnet->tcp_reuse_first->lru_prev));
}
if(reuse->lru_next) {
/* assert that members of the lru list are waiting
* and thus have a pending pointer to the struct */
log_assert(reuse->lru_next->pending);
reuse->lru_next->lru_prev = reuse->lru_prev;
log_assert(reuse->lru_next->lru_prev != reuse->lru_next);
} else {
log_assert(!reuse->lru_prev || reuse->lru_prev->pending);
outnet->tcp_reuse_last = reuse->lru_prev;
log_assert(!outnet->tcp_reuse_last ||
(outnet->tcp_reuse_last !=
outnet->tcp_reuse_last->lru_next &&
outnet->tcp_reuse_last !=
outnet->tcp_reuse_last->lru_prev));
}
log_assert((!outnet->tcp_reuse_first && !outnet->tcp_reuse_last) ||
(outnet->tcp_reuse_first && outnet->tcp_reuse_last));
reuse->item_on_lru_list = 0;
reuse->lru_next = NULL;
reuse->lru_prev = NULL;
}
reuse->pending = NULL;
}
/** helper function that deletes an element from the tree of readwait
* elements in tcp reuse structure */
static void reuse_del_readwait_elem(rbnode_type* node, void* ATTR_UNUSED(arg))
{
struct waiting_tcp* w = (struct waiting_tcp*)node->key;
waiting_tcp_delete(w);
}
/** delete readwait waiting_tcp elements, deletes the elements in the list */
void reuse_del_readwait(rbtree_type* tree_by_id)
{
if(tree_by_id->root == NULL ||
tree_by_id->root == RBTREE_NULL)
return;
traverse_postorder(tree_by_id, &reuse_del_readwait_elem, NULL);
rbtree_init(tree_by_id, reuse_id_cmp);
}
/** decommission a tcp buffer, closes commpoint and frees waiting_tcp entry */
static void
decommission_pending_tcp(struct outside_network* outnet,
struct pending_tcp* pend)
{
verbose(VERB_CLIENT, "decommission_pending_tcp");
/* A certain code path can lead here twice for the same pending_tcp
* creating a loop in the free pending_tcp list. */
if(outnet->tcp_free != pend) {
pend->next_free = outnet->tcp_free;
outnet->tcp_free = pend;
}
if(pend->reuse.node.key) {
/* needs unlink from the reuse tree to get deleted */
reuse_tcp_remove_tree_list(outnet, &pend->reuse);
}
/* free SSL structure after remove from outnet tcp reuse tree,
* because the c->ssl null or not is used for sorting in the tree */
if(pend->c->ssl) {
#ifdef HAVE_SSL
SSL_shutdown(pend->c->ssl);
SSL_free(pend->c->ssl);
pend->c->ssl = NULL;
#endif
}
comm_point_close(pend->c);
pend->reuse.cp_more_read_again = 0;
pend->reuse.cp_more_write_again = 0;
/* unlink the query and writewait list, it is part of the tree
* nodes and is deleted */
pend->query = NULL;
pend->reuse.write_wait_first = NULL;
pend->reuse.write_wait_last = NULL;
reuse_del_readwait(&pend->reuse.tree_by_id);
}
/** perform failure callbacks for waiting queries in reuse read rbtree */
static void reuse_cb_readwait_for_failure(rbtree_type* tree_by_id, int err)
{
rbnode_type* node;
if(tree_by_id->root == NULL ||
tree_by_id->root == RBTREE_NULL)
return;
node = rbtree_first(tree_by_id);
while(node && node != RBTREE_NULL) {
struct waiting_tcp* w = (struct waiting_tcp*)node->key;
waiting_tcp_callback(w, NULL, err, NULL);
node = rbtree_next(node);
}
}
/** mark the entry for being in the cb_and_decommission stage */
static void mark_for_cb_and_decommission(rbnode_type* node,
void* ATTR_UNUSED(arg))
{
struct waiting_tcp* w = (struct waiting_tcp*)node->key;
/* Mark the waiting_tcp to signal later code (serviced_delete) that
* this item is part of the backed up tree_by_id and will be deleted
* later. */
w->in_cb_and_decommission = 1;
/* Mark the serviced_query for deletion so that later code through
* callbacks (iter_clear .. outnet_serviced_query_stop) won't
* prematurely delete it. */
if(w->cb)
((struct serviced_query*)w->cb_arg)->to_be_deleted = 1;
}
/** perform callbacks for failure and also decommission pending tcp.
* the callbacks remove references in sq->pending to the waiting_tcp
* members of the tree_by_id in the pending tcp. The pending_tcp is
* removed before the callbacks, so that the callbacks do not modify
* the pending_tcp due to its reference in the outside_network reuse tree */
static void reuse_cb_and_decommission(struct outside_network* outnet,
struct pending_tcp* pend, int error)
{
rbtree_type store;
store = pend->reuse.tree_by_id;
pend->query = NULL;
rbtree_init(&pend->reuse.tree_by_id, reuse_id_cmp);
pend->reuse.write_wait_first = NULL;
pend->reuse.write_wait_last = NULL;
decommission_pending_tcp(outnet, pend);
if(store.root != NULL && store.root != RBTREE_NULL) {
traverse_postorder(&store, &mark_for_cb_and_decommission, NULL);
}
reuse_cb_readwait_for_failure(&store, error);
reuse_del_readwait(&store);
}
/** set timeout on tcp fd and setup read event to catch incoming dns msgs */
static void
reuse_tcp_setup_timeout(struct pending_tcp* pend_tcp, int tcp_reuse_timeout)
{
log_reuse_tcp(VERB_CLIENT, "reuse_tcp_setup_timeout", &pend_tcp->reuse);
comm_point_start_listening(pend_tcp->c, -1, tcp_reuse_timeout);
}
/** set timeout on tcp fd and setup read event to catch incoming dns msgs */
static void
reuse_tcp_setup_read_and_timeout(struct pending_tcp* pend_tcp, int tcp_reuse_timeout)
{
log_reuse_tcp(VERB_CLIENT, "reuse_tcp_setup_readtimeout", &pend_tcp->reuse);
sldns_buffer_clear(pend_tcp->c->buffer);
pend_tcp->c->tcp_is_reading = 1;
pend_tcp->c->tcp_byte_count = 0;
comm_point_stop_listening(pend_tcp->c);
comm_point_start_listening(pend_tcp->c, -1, tcp_reuse_timeout);
}
int
outnet_tcp_cb(struct comm_point* c, void* arg, int error,
struct comm_reply *reply_info)
{
struct pending_tcp* pend = (struct pending_tcp*)arg;
struct outside_network* outnet = pend->reuse.outnet;
struct waiting_tcp* w = NULL;
log_assert(pend->reuse.item_on_lru_list && pend->reuse.node.key);
verbose(VERB_ALGO, "outnettcp cb");
if(error == NETEVENT_TIMEOUT) {
if(pend->c->tcp_write_and_read) {
verbose(VERB_QUERY, "outnettcp got tcp timeout "
"for read, ignored because write underway");
/* if we are writing, ignore readtimer, wait for write timer
* or write is done */
return 0;
} else {
verbose(VERB_QUERY, "outnettcp got tcp timeout %s",
(pend->reuse.tree_by_id.count?"for reading pkt":
"for keepalive for reuse"));
}
/* must be timeout for reading or keepalive reuse,
* close it. */
reuse_tcp_remove_tree_list(outnet, &pend->reuse);
} else if(error == NETEVENT_PKT_WRITTEN) {
/* the packet we want to write has been written. */
verbose(VERB_ALGO, "outnet tcp pkt was written event");
log_assert(c == pend->c);
log_assert(pend->query->pkt == pend->c->tcp_write_pkt);
log_assert(pend->query->pkt_len == pend->c->tcp_write_pkt_len);
pend->c->tcp_write_pkt = NULL;
pend->c->tcp_write_pkt_len = 0;
/* the pend.query is already in tree_by_id */
log_assert(pend->query->id_node.key);
pend->query = NULL;
/* setup to write next packet or setup read timeout */
if(pend->reuse.write_wait_first) {
verbose(VERB_ALGO, "outnet tcp setup next pkt");
/* we can write it straight away perhaps, set flag
* because this callback called after a tcp write
* succeeded and likely more buffer space is available
* and we can write some more. */
pend->reuse.cp_more_write_again = 1;
pend->query = reuse_write_wait_pop(&pend->reuse);
comm_point_stop_listening(pend->c);
outnet_tcp_take_query_setup(pend->c->fd, pend,
pend->query);
} else {
verbose(VERB_ALGO, "outnet tcp writes done, wait");
pend->c->tcp_write_and_read = 0;
pend->reuse.cp_more_read_again = 0;
pend->reuse.cp_more_write_again = 0;
pend->c->tcp_is_reading = 1;
comm_point_stop_listening(pend->c);
reuse_tcp_setup_timeout(pend, outnet->tcp_reuse_timeout);
}
return 0;
} else if(error != NETEVENT_NOERROR) {
verbose(VERB_QUERY, "outnettcp got tcp error %d", error);
reuse_move_writewait_away(outnet, pend);
/* pass error below and exit */
} else {
/* check ID */
if(sldns_buffer_limit(c->buffer) < sizeof(uint16_t)) {
log_addr(VERB_QUERY,
"outnettcp: bad ID in reply, too short, from:",
&pend->reuse.addr, pend->reuse.addrlen);
error = NETEVENT_CLOSED;
} else {
uint16_t id = LDNS_ID_WIRE(sldns_buffer_begin(
c->buffer));
/* find the query the reply is for */
w = reuse_tcp_by_id_find(&pend->reuse, id);
/* Make sure that the reply we got is at least for a
* sent query with the same ID; the waiting_tcp that
* gets a reply is assumed to not be waiting to be
* sent. */
if(w && (w->on_tcp_waiting_list || w->write_wait_queued))
w = NULL;
}
}
if(error == NETEVENT_NOERROR && !w) {
/* no struct waiting found in tree, no reply to call */
log_addr(VERB_QUERY, "outnettcp: bad ID in reply, from:",
&pend->reuse.addr, pend->reuse.addrlen);
error = NETEVENT_CLOSED;
}
if(error == NETEVENT_NOERROR) {
/* add to reuse tree so it can be reused, if not a failure.
* This is possible if the state machine wants to make a tcp
* query again to the same destination. */
if(outnet->tcp_reuse.count < outnet->tcp_reuse_max) {
(void)reuse_tcp_insert(outnet, pend);
}
}
if(w) {
log_assert(!w->on_tcp_waiting_list);
log_assert(!w->write_wait_queued);
reuse_tree_by_id_delete(&pend->reuse, w);
verbose(VERB_CLIENT, "outnet tcp callback query err %d buflen %d",
error, (int)sldns_buffer_limit(c->buffer));
waiting_tcp_callback(w, c, error, reply_info);
waiting_tcp_delete(w);
}
verbose(VERB_CLIENT, "outnet_tcp_cb reuse after cb");
if(error == NETEVENT_NOERROR && pend->reuse.node.key) {
verbose(VERB_CLIENT, "outnet_tcp_cb reuse after cb: keep it");
/* it is in the reuse_tcp tree, with other queries, or
* on the empty list. do not decommission it */
/* if there are more outstanding queries, we could try to
* read again, to see if it is on the input,
* because this callback called after a successful read
* and there could be more bytes to read on the input */
if(pend->reuse.tree_by_id.count != 0)
pend->reuse.cp_more_read_again = 1;
reuse_tcp_setup_read_and_timeout(pend, outnet->tcp_reuse_timeout);
return 0;
}
verbose(VERB_CLIENT, "outnet_tcp_cb reuse after cb: decommission it");
/* no queries on it, no space to keep it. or timeout or closed due
* to error. Close it */
reuse_cb_and_decommission(outnet, pend, (error==NETEVENT_TIMEOUT?
NETEVENT_TIMEOUT:NETEVENT_CLOSED));
use_free_buffer(outnet);
return 0;
}
/** lower use count on pc, see if it can be closed */
static void
portcomm_loweruse(struct outside_network* outnet, struct port_comm* pc)
{
struct port_if* pif;
pc->num_outstanding--;
if(pc->num_outstanding > 0) {
return;
}
/* close it and replace in unused list */
verbose(VERB_ALGO, "close of port %d", pc->number);
comm_point_close(pc->cp);
pif = pc->pif;
log_assert(pif->inuse > 0);
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
pif->avail_ports[pif->avail_total - pif->inuse] = pc->number;
#endif
pif->inuse--;
pif->out[pc->index] = pif->out[pif->inuse];
pif->out[pc->index]->index = pc->index;
pc->next = outnet->unused_fds;
outnet->unused_fds = pc;
}
/** try to send waiting UDP queries */
static void
outnet_send_wait_udp(struct outside_network* outnet)
{
struct pending* pend;
/* process waiting queries */
while(outnet->udp_wait_first && outnet->unused_fds
&& !outnet->want_to_quit) {
pend = outnet->udp_wait_first;
outnet->udp_wait_first = pend->next_waiting;
if(!pend->next_waiting) outnet->udp_wait_last = NULL;
sldns_buffer_clear(outnet->udp_buff);
sldns_buffer_write(outnet->udp_buff, pend->pkt, pend->pkt_len);
sldns_buffer_flip(outnet->udp_buff);
free(pend->pkt); /* freeing now makes get_mem correct */
pend->pkt = NULL;
pend->pkt_len = 0;
log_assert(!pend->sq->busy);
pend->sq->busy = 1;
if(!randomize_and_send_udp(pend, outnet->udp_buff,
pend->timeout)) {
/* callback error on pending */
if(pend->cb) {
fptr_ok(fptr_whitelist_pending_udp(pend->cb));
(void)(*pend->cb)(outnet->unused_fds->cp, pend->cb_arg,
NETEVENT_CLOSED, NULL);
}
pending_delete(outnet, pend);
} else {
pend->sq->busy = 0;
}
}
}
int
outnet_udp_cb(struct comm_point* c, void* arg, int error,
struct comm_reply *reply_info)
{
struct outside_network* outnet = (struct outside_network*)arg;
struct pending key;
struct pending* p;
verbose(VERB_ALGO, "answer cb");
if(error != NETEVENT_NOERROR) {
verbose(VERB_QUERY, "outnetudp got udp error %d", error);
return 0;
}
if(sldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE) {
verbose(VERB_QUERY, "outnetudp udp too short");
return 0;
}
log_assert(reply_info);
/* setup lookup key */
key.id = (unsigned)LDNS_ID_WIRE(sldns_buffer_begin(c->buffer));
memcpy(&key.addr, &reply_info->remote_addr, reply_info->remote_addrlen);
key.addrlen = reply_info->remote_addrlen;
verbose(VERB_ALGO, "Incoming reply id = %4.4x", key.id);
log_addr(VERB_ALGO, "Incoming reply addr =",
&reply_info->remote_addr, reply_info->remote_addrlen);
/* find it, see if this thing is a valid query response */
verbose(VERB_ALGO, "lookup size is %d entries", (int)outnet->pending->count);
p = (struct pending*)rbtree_search(outnet->pending, &key);
if(!p) {
verbose(VERB_QUERY, "received unwanted or unsolicited udp reply dropped.");
log_buf(VERB_ALGO, "dropped message", c->buffer);
outnet->unwanted_replies++;
if(outnet->unwanted_threshold && ++outnet->unwanted_total
>= outnet->unwanted_threshold) {
log_warn("unwanted reply total reached threshold (%u)"
" you may be under attack."
" defensive action: clearing the cache",
(unsigned)outnet->unwanted_threshold);
fptr_ok(fptr_whitelist_alloc_cleanup(
outnet->unwanted_action));
(*outnet->unwanted_action)(outnet->unwanted_param);
outnet->unwanted_total = 0;
}
return 0;
}
verbose(VERB_ALGO, "received udp reply.");
log_buf(VERB_ALGO, "udp message", c->buffer);
if(p->pc->cp != c) {
verbose(VERB_QUERY, "received reply id,addr on wrong port. "
"dropped.");
outnet->unwanted_replies++;
if(outnet->unwanted_threshold && ++outnet->unwanted_total
>= outnet->unwanted_threshold) {
log_warn("unwanted reply total reached threshold (%u)"
" you may be under attack."
" defensive action: clearing the cache",
(unsigned)outnet->unwanted_threshold);
fptr_ok(fptr_whitelist_alloc_cleanup(
outnet->unwanted_action));
(*outnet->unwanted_action)(outnet->unwanted_param);
outnet->unwanted_total = 0;
}
return 0;
}
comm_timer_disable(p->timer);
verbose(VERB_ALGO, "outnet handle udp reply");
/* delete from tree first in case callback creates a retry */
(void)rbtree_delete(outnet->pending, p->node.key);
if(p->cb) {
fptr_ok(fptr_whitelist_pending_udp(p->cb));
(void)(*p->cb)(p->pc->cp, p->cb_arg, NETEVENT_NOERROR, reply_info);
}
portcomm_loweruse(outnet, p->pc);
pending_delete(NULL, p);
outnet_send_wait_udp(outnet);
return 0;
}
/** calculate number of ip4 and ip6 interfaces*/
static void
calc_num46(char** ifs, int num_ifs, int do_ip4, int do_ip6,
int* num_ip4, int* num_ip6)
{
int i;
*num_ip4 = 0;
*num_ip6 = 0;
if(num_ifs <= 0) {
if(do_ip4)
*num_ip4 = 1;
if(do_ip6)
*num_ip6 = 1;
return;
}
for(i=0; i<num_ifs; i++)
{
if(str_is_ip6(ifs[i])) {
if(do_ip6)
(*num_ip6)++;
} else {
if(do_ip4)
(*num_ip4)++;
}
}
}
void
pending_udp_timer_delay_cb(void* arg)
{
struct pending* p = (struct pending*)arg;
struct outside_network* outnet = p->outnet;
verbose(VERB_ALGO, "timeout udp with delay");
portcomm_loweruse(outnet, p->pc);
pending_delete(outnet, p);
outnet_send_wait_udp(outnet);
}
void
pending_udp_timer_cb(void *arg)
{
struct pending* p = (struct pending*)arg;
struct outside_network* outnet = p->outnet;
/* it timed out */
verbose(VERB_ALGO, "timeout udp");
if(p->cb) {
fptr_ok(fptr_whitelist_pending_udp(p->cb));
(void)(*p->cb)(p->pc->cp, p->cb_arg, NETEVENT_TIMEOUT, NULL);
}
/* if delayclose, keep port open for a longer time.
* But if the udpwaitlist exists, then we are struggling to
* keep up with demand for sockets, so do not wait, but service
* the customer (customer service more important than portICMPs) */
if(outnet->delayclose && !outnet->udp_wait_first) {
p->cb = NULL;
p->timer->callback = &pending_udp_timer_delay_cb;
comm_timer_set(p->timer, &outnet->delay_tv);
return;
}
portcomm_loweruse(outnet, p->pc);
pending_delete(outnet, p);
outnet_send_wait_udp(outnet);
}
/** create pending_tcp buffers */
static int
create_pending_tcp(struct outside_network* outnet, size_t bufsize)
{
size_t i;
if(outnet->num_tcp == 0)
return 1; /* no tcp needed, nothing to do */
if(!(outnet->tcp_conns = (struct pending_tcp **)calloc(
outnet->num_tcp, sizeof(struct pending_tcp*))))
return 0;
for(i=0; i<outnet->num_tcp; i++) {
if(!(outnet->tcp_conns[i] = (struct pending_tcp*)calloc(1,
sizeof(struct pending_tcp))))
return 0;
outnet->tcp_conns[i]->next_free = outnet->tcp_free;
outnet->tcp_free = outnet->tcp_conns[i];
outnet->tcp_conns[i]->c = comm_point_create_tcp_out(
outnet->base, bufsize, outnet_tcp_cb,
outnet->tcp_conns[i]);
if(!outnet->tcp_conns[i]->c)
return 0;
}
return 1;
}
/** setup an outgoing interface, ready address */
static int setup_if(struct port_if* pif, const char* addrstr,
int* avail, int numavail, size_t numfd)
{
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
pif->avail_total = numavail;
pif->avail_ports = (int*)memdup(avail, (size_t)numavail*sizeof(int));
if(!pif->avail_ports)
return 0;
#endif
if(!ipstrtoaddr(addrstr, UNBOUND_DNS_PORT, &pif->addr, &pif->addrlen) &&
!netblockstrtoaddr(addrstr, UNBOUND_DNS_PORT,
&pif->addr, &pif->addrlen, &pif->pfxlen))
return 0;
pif->maxout = (int)numfd;
pif->inuse = 0;
pif->out = (struct port_comm**)calloc(numfd,
sizeof(struct port_comm*));
if(!pif->out)
return 0;
return 1;
}
struct outside_network*
outside_network_create(struct comm_base *base, size_t bufsize,
size_t num_ports, char** ifs, int num_ifs, int do_ip4,
int do_ip6, size_t num_tcp, int dscp, struct infra_cache* infra,
struct ub_randstate* rnd, int use_caps_for_id, int* availports,
int numavailports, size_t unwanted_threshold, int tcp_mss,
void (*unwanted_action)(void*), void* unwanted_param, int do_udp,
void* sslctx, int delayclose, int tls_use_sni, struct dt_env* dtenv,
int udp_connect, int max_reuse_tcp_queries, int tcp_reuse_timeout,
int tcp_auth_query_timeout)
{
struct outside_network* outnet = (struct outside_network*)
calloc(1, sizeof(struct outside_network));
size_t k;
if(!outnet) {
log_err("malloc failed");
return NULL;
}
comm_base_timept(base, &outnet->now_secs, &outnet->now_tv);
outnet->base = base;
outnet->num_tcp = num_tcp;
outnet->max_reuse_tcp_queries = max_reuse_tcp_queries;
outnet->tcp_reuse_timeout= tcp_reuse_timeout;
outnet->tcp_auth_query_timeout = tcp_auth_query_timeout;
outnet->num_tcp_outgoing = 0;
outnet->num_udp_outgoing = 0;
outnet->infra = infra;
outnet->rnd = rnd;
outnet->sslctx = sslctx;
outnet->tls_use_sni = tls_use_sni;
#ifdef USE_DNSTAP
outnet->dtenv = dtenv;
#else
(void)dtenv;
#endif
outnet->svcd_overhead = 0;
outnet->want_to_quit = 0;
outnet->unwanted_threshold = unwanted_threshold;
outnet->unwanted_action = unwanted_action;
outnet->unwanted_param = unwanted_param;
outnet->use_caps_for_id = use_caps_for_id;
outnet->do_udp = do_udp;
outnet->tcp_mss = tcp_mss;
outnet->ip_dscp = dscp;
#ifndef S_SPLINT_S
if(delayclose) {
outnet->delayclose = 1;
outnet->delay_tv.tv_sec = delayclose/1000;
outnet->delay_tv.tv_usec = (delayclose%1000)*1000;
}
#endif
if(udp_connect) {
outnet->udp_connect = 1;
}
if(numavailports == 0 || num_ports == 0) {
log_err("no outgoing ports available");
outside_network_delete(outnet);
return NULL;
}
#ifndef INET6
do_ip6 = 0;
#endif
calc_num46(ifs, num_ifs, do_ip4, do_ip6,
&outnet->num_ip4, &outnet->num_ip6);
if(outnet->num_ip4 != 0) {
if(!(outnet->ip4_ifs = (struct port_if*)calloc(
(size_t)outnet->num_ip4, sizeof(struct port_if)))) {
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
}
if(outnet->num_ip6 != 0) {
if(!(outnet->ip6_ifs = (struct port_if*)calloc(
(size_t)outnet->num_ip6, sizeof(struct port_if)))) {
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
}
if( !(outnet->udp_buff = sldns_buffer_new(bufsize)) ||
!(outnet->pending = rbtree_create(pending_cmp)) ||
!(outnet->serviced = rbtree_create(serviced_cmp)) ||
!create_pending_tcp(outnet, bufsize)) {
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
rbtree_init(&outnet->tcp_reuse, reuse_cmp);
outnet->tcp_reuse_max = num_tcp;
/* allocate commpoints */
for(k=0; k<num_ports; k++) {
struct port_comm* pc;
pc = (struct port_comm*)calloc(1, sizeof(*pc));
if(!pc) {
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
pc->cp = comm_point_create_udp(outnet->base, -1,
outnet->udp_buff, 0, outnet_udp_cb, outnet, NULL);
if(!pc->cp) {
log_err("malloc failed");
free(pc);
outside_network_delete(outnet);
return NULL;
}
pc->next = outnet->unused_fds;
outnet->unused_fds = pc;
}
/* allocate interfaces */
if(num_ifs == 0) {
if(do_ip4 && !setup_if(&outnet->ip4_ifs[0], "0.0.0.0",
availports, numavailports, num_ports)) {
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
if(do_ip6 && !setup_if(&outnet->ip6_ifs[0], "::",
availports, numavailports, num_ports)) {
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
} else {
size_t done_4 = 0, done_6 = 0;
int i;
for(i=0; i<num_ifs; i++) {
if(str_is_ip6(ifs[i]) && do_ip6) {
if(!setup_if(&outnet->ip6_ifs[done_6], ifs[i],
availports, numavailports, num_ports)){
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
done_6++;
}
if(!str_is_ip6(ifs[i]) && do_ip4) {
if(!setup_if(&outnet->ip4_ifs[done_4], ifs[i],
availports, numavailports, num_ports)){
log_err("malloc failed");
outside_network_delete(outnet);
return NULL;
}
done_4++;
}
}
}
return outnet;
}
/** helper pending delete */
static void
pending_node_del(rbnode_type* node, void* arg)
{
struct pending* pend = (struct pending*)node;
struct outside_network* outnet = (struct outside_network*)arg;
pending_delete(outnet, pend);
}
/** helper serviced delete */
static void
serviced_node_del(rbnode_type* node, void* ATTR_UNUSED(arg))
{
struct serviced_query* sq = (struct serviced_query*)node;
alloc_reg_release(sq->alloc, sq->region);
if(sq->timer)
comm_timer_delete(sq->timer);
free(sq);
}
void
outside_network_quit_prepare(struct outside_network* outnet)
{
if(!outnet)
return;
/* prevent queued items from being sent */
outnet->want_to_quit = 1;
}
void
outside_network_delete(struct outside_network* outnet)
{
if(!outnet)
return;
outnet->want_to_quit = 1;
/* check every element, since we can be called on malloc error */
if(outnet->pending) {
/* free pending elements, but do no unlink from tree. */
traverse_postorder(outnet->pending, pending_node_del, NULL);
free(outnet->pending);
}
if(outnet->serviced) {
traverse_postorder(outnet->serviced, serviced_node_del, NULL);
free(outnet->serviced);
}
if(outnet->udp_buff)
sldns_buffer_free(outnet->udp_buff);
if(outnet->unused_fds) {
struct port_comm* p = outnet->unused_fds, *np;
while(p) {
np = p->next;
comm_point_delete(p->cp);
free(p);
p = np;
}
outnet->unused_fds = NULL;
}
if(outnet->ip4_ifs) {
int i, k;
for(i=0; i<outnet->num_ip4; i++) {
for(k=0; k<outnet->ip4_ifs[i].inuse; k++) {
struct port_comm* pc = outnet->ip4_ifs[i].
out[k];
comm_point_delete(pc->cp);
free(pc);
}
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
free(outnet->ip4_ifs[i].avail_ports);
#endif
free(outnet->ip4_ifs[i].out);
}
free(outnet->ip4_ifs);
}
if(outnet->ip6_ifs) {
int i, k;
for(i=0; i<outnet->num_ip6; i++) {
for(k=0; k<outnet->ip6_ifs[i].inuse; k++) {
struct port_comm* pc = outnet->ip6_ifs[i].
out[k];
comm_point_delete(pc->cp);
free(pc);
}
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
free(outnet->ip6_ifs[i].avail_ports);
#endif
free(outnet->ip6_ifs[i].out);
}
free(outnet->ip6_ifs);
}
if(outnet->tcp_conns) {
size_t i;
for(i=0; i<outnet->num_tcp; i++)
if(outnet->tcp_conns[i]) {
struct pending_tcp* pend;
pend = outnet->tcp_conns[i];
if(pend->reuse.item_on_lru_list) {
/* delete waiting_tcp elements that
* the tcp conn is working on */
decommission_pending_tcp(outnet, pend);
}
comm_point_delete(outnet->tcp_conns[i]->c);
free(outnet->tcp_conns[i]);
outnet->tcp_conns[i] = NULL;
}
free(outnet->tcp_conns);
outnet->tcp_conns = NULL;
}
if(outnet->tcp_wait_first) {
struct waiting_tcp* p = outnet->tcp_wait_first, *np;
while(p) {
np = p->next_waiting;
waiting_tcp_delete(p);
p = np;
}
}
/* was allocated in struct pending that was deleted above */
rbtree_init(&outnet->tcp_reuse, reuse_cmp);
outnet->tcp_reuse_first = NULL;
outnet->tcp_reuse_last = NULL;
if(outnet->udp_wait_first) {
struct pending* p = outnet->udp_wait_first, *np;
while(p) {
np = p->next_waiting;
pending_delete(NULL, p);
p = np;
}
}
free(outnet);
}
void
pending_delete(struct outside_network* outnet, struct pending* p)
{
if(!p)
return;
if(outnet && outnet->udp_wait_first &&
(p->next_waiting || p == outnet->udp_wait_last) ) {
/* delete from waiting list, if it is in the waiting list */
struct pending* prev = NULL, *x = outnet->udp_wait_first;
while(x && x != p) {
prev = x;
x = x->next_waiting;
}
if(x) {
log_assert(x == p);
if(prev)
prev->next_waiting = p->next_waiting;
else outnet->udp_wait_first = p->next_waiting;
if(outnet->udp_wait_last == p)
outnet->udp_wait_last = prev;
}
}
if(outnet) {
(void)rbtree_delete(outnet->pending, p->node.key);
}
if(p->timer)
comm_timer_delete(p->timer);
free(p->pkt);
free(p);
}
static void
sai6_putrandom(struct sockaddr_in6 *sa, int pfxlen, struct ub_randstate *rnd)
{
int i, last;
if(!(pfxlen > 0 && pfxlen < 128))
return;
for(i = 0; i < (128 - pfxlen) / 8; i++) {
sa->sin6_addr.s6_addr[15-i] = (uint8_t)ub_random_max(rnd, 256);
}
last = pfxlen & 7;
if(last != 0) {
sa->sin6_addr.s6_addr[15-i] |=
((0xFF >> last) & ub_random_max(rnd, 256));
}
}
/**
* Try to open a UDP socket for outgoing communication.
* Sets sockets options as needed.
* @param addr: socket address.
* @param addrlen: length of address.
* @param pfxlen: length of network prefix (for address randomisation).
* @param port: port override for addr.
* @param inuse: if -1 is returned, this bool means the port was in use.
* @param rnd: random state (for address randomisation).
* @param dscp: DSCP to use.
* @return fd or -1
*/
static int
udp_sockport(struct sockaddr_storage* addr, socklen_t addrlen, int pfxlen,
int port, int* inuse, struct ub_randstate* rnd, int dscp)
{
int fd, noproto;
if(addr_is_ip6(addr, addrlen)) {
int freebind = 0;
struct sockaddr_in6 sa = *(struct sockaddr_in6*)addr;
sa.sin6_port = (in_port_t)htons((uint16_t)port);
sa.sin6_flowinfo = 0;
sa.sin6_scope_id = 0;
if(pfxlen != 0) {
freebind = 1;
sai6_putrandom(&sa, pfxlen, rnd);
}
fd = create_udp_sock(AF_INET6, SOCK_DGRAM,
(struct sockaddr*)&sa, addrlen, 1, inuse, &noproto,
0, 0, 0, NULL, 0, freebind, 0, dscp);
} else {
struct sockaddr_in* sa = (struct sockaddr_in*)addr;
sa->sin_port = (in_port_t)htons((uint16_t)port);
fd = create_udp_sock(AF_INET, SOCK_DGRAM,
(struct sockaddr*)addr, addrlen, 1, inuse, &noproto,
0, 0, 0, NULL, 0, 0, 0, dscp);
}
return fd;
}
/** Select random ID */
static int
select_id(struct outside_network* outnet, struct pending* pend,
sldns_buffer* packet)
{
int id_tries = 0;
pend->id = GET_RANDOM_ID(outnet->rnd);
LDNS_ID_SET(sldns_buffer_begin(packet), pend->id);
/* insert in tree */
pend->node.key = pend;
while(!rbtree_insert(outnet->pending, &pend->node)) {
/* change ID to avoid collision */
pend->id = GET_RANDOM_ID(outnet->rnd);
LDNS_ID_SET(sldns_buffer_begin(packet), pend->id);
id_tries++;
if(id_tries == MAX_ID_RETRY) {
pend->id=99999; /* non existent ID */
log_err("failed to generate unique ID, drop msg");
return 0;
}
}
verbose(VERB_ALGO, "inserted new pending reply id=%4.4x", pend->id);
return 1;
}
/** return true is UDP connect error needs to be logged */
static int udp_connect_needs_log(int err)
{
switch(err) {
case ECONNREFUSED:
# ifdef ENETUNREACH
case ENETUNREACH:
# endif
# ifdef EHOSTDOWN
case EHOSTDOWN:
# endif
# ifdef EHOSTUNREACH
case EHOSTUNREACH:
# endif
# ifdef ENETDOWN
case ENETDOWN:
# endif
# ifdef EADDRNOTAVAIL
case EADDRNOTAVAIL:
# endif
case EPERM:
case EACCES:
if(verbosity >= VERB_ALGO)
return 1;
return 0;
default:
break;
}
return 1;
}
/** Select random interface and port */
static int
select_ifport(struct outside_network* outnet, struct pending* pend,
int num_if, struct port_if* ifs)
{
int my_if, my_port, fd, portno, inuse, tries=0;
struct port_if* pif;
/* randomly select interface and port */
if(num_if == 0) {
verbose(VERB_QUERY, "Need to send query but have no "
"outgoing interfaces of that family");
return 0;
}
log_assert(outnet->unused_fds);
tries = 0;
while(1) {
my_if = ub_random_max(outnet->rnd, num_if);
pif = &ifs[my_if];
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
if(outnet->udp_connect) {
/* if we connect() we cannot reuse fds for a port */
if(pif->inuse >= pif->avail_total) {
tries++;
if(tries < MAX_PORT_RETRY)
continue;
log_err("failed to find an open port, drop msg");
return 0;
}
my_port = pif->inuse + ub_random_max(outnet->rnd,
pif->avail_total - pif->inuse);
} else {
my_port = ub_random_max(outnet->rnd, pif->avail_total);
if(my_port < pif->inuse) {
/* port already open */
pend->pc = pif->out[my_port];
verbose(VERB_ALGO, "using UDP if=%d port=%d",
my_if, pend->pc->number);
break;
}
}
/* try to open new port, if fails, loop to try again */
log_assert(pif->inuse < pif->maxout);
portno = pif->avail_ports[my_port - pif->inuse];
#else
my_port = portno = 0;
#endif
fd = udp_sockport(&pif->addr, pif->addrlen, pif->pfxlen,
portno, &inuse, outnet->rnd, outnet->ip_dscp);
if(fd == -1 && !inuse) {
/* nonrecoverable error making socket */
return 0;
}
if(fd != -1) {
verbose(VERB_ALGO, "opened UDP if=%d port=%d",
my_if, portno);
if(outnet->udp_connect) {
/* connect() to the destination */
if(connect(fd, (struct sockaddr*)&pend->addr,
pend->addrlen) < 0) {
if(udp_connect_needs_log(errno)) {
log_err_addr("udp connect failed",
strerror(errno), &pend->addr,
pend->addrlen);
}
sock_close(fd);
return 0;
}
}
/* grab fd */
pend->pc = outnet->unused_fds;
outnet->unused_fds = pend->pc->next;
/* setup portcomm */
pend->pc->next = NULL;
pend->pc->number = portno;
pend->pc->pif = pif;
pend->pc->index = pif->inuse;
pend->pc->num_outstanding = 0;
comm_point_start_listening(pend->pc->cp, fd, -1);
/* grab port in interface */
pif->out[pif->inuse] = pend->pc;
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
pif->avail_ports[my_port - pif->inuse] =
pif->avail_ports[pif->avail_total-pif->inuse-1];
#endif
pif->inuse++;
break;
}
/* failed, already in use */
verbose(VERB_QUERY, "port %d in use, trying another", portno);
tries++;
if(tries == MAX_PORT_RETRY) {
log_err("failed to find an open port, drop msg");
return 0;
}
}
log_assert(pend->pc);
pend->pc->num_outstanding++;
return 1;
}
static int
randomize_and_send_udp(struct pending* pend, sldns_buffer* packet, int timeout)
{
struct timeval tv;
struct outside_network* outnet = pend->sq->outnet;
/* select id */
if(!select_id(outnet, pend, packet)) {
return 0;
}
/* select src_if, port */
if(addr_is_ip6(&pend->addr, pend->addrlen)) {
if(!select_ifport(outnet, pend,
outnet->num_ip6, outnet->ip6_ifs))
return 0;
} else {
if(!select_ifport(outnet, pend,
outnet->num_ip4, outnet->ip4_ifs))
return 0;
}
log_assert(pend->pc && pend->pc->cp);
/* send it over the commlink */
if(!comm_point_send_udp_msg(pend->pc->cp, packet,
(struct sockaddr*)&pend->addr, pend->addrlen, outnet->udp_connect)) {
portcomm_loweruse(outnet, pend->pc);
return 0;
}
outnet->num_udp_outgoing++;
/* system calls to set timeout after sending UDP to make roundtrip
smaller. */
#ifndef S_SPLINT_S
tv.tv_sec = timeout/1000;
tv.tv_usec = (timeout%1000)*1000;
#endif
comm_timer_set(pend->timer, &tv);
#ifdef USE_DNSTAP
/*
* sending src (local service)/dst (upstream) addresses over DNSTAP
* There are no chances to get the src (local service) addr if unbound
* is not configured with specific outgoing IP-addresses. So we will
* pass 0.0.0.0 (::) to argument for
* dt_msg_send_outside_query()/dt_msg_send_outside_response() calls.
*/
if(outnet->dtenv &&
(outnet->dtenv->log_resolver_query_messages ||
outnet->dtenv->log_forwarder_query_messages)) {
log_addr(VERB_ALGO, "from local addr", &pend->pc->pif->addr, pend->pc->pif->addrlen);
log_addr(VERB_ALGO, "request to upstream", &pend->addr, pend->addrlen);
dt_msg_send_outside_query(outnet->dtenv, &pend->addr, &pend->pc->pif->addr, comm_udp, NULL,
pend->sq->zone, pend->sq->zonelen, packet);
}
#endif
return 1;
}
struct pending*
pending_udp_query(struct serviced_query* sq, struct sldns_buffer* packet,
int timeout, comm_point_callback_type* cb, void* cb_arg)
{
struct pending* pend = (struct pending*)calloc(1, sizeof(*pend));
if(!pend) return NULL;
pend->outnet = sq->outnet;
pend->sq = sq;
pend->addrlen = sq->addrlen;
memmove(&pend->addr, &sq->addr, sq->addrlen);
pend->cb = cb;
pend->cb_arg = cb_arg;
pend->node.key = pend;
pend->timer = comm_timer_create(sq->outnet->base, pending_udp_timer_cb,
pend);
if(!pend->timer) {
free(pend);
return NULL;
}
if(sq->outnet->unused_fds == NULL) {
/* no unused fd, cannot create a new port (randomly) */
verbose(VERB_ALGO, "no fds available, udp query waiting");
pend->timeout = timeout;
pend->pkt_len = sldns_buffer_limit(packet);
pend->pkt = (uint8_t*)memdup(sldns_buffer_begin(packet),
pend->pkt_len);
if(!pend->pkt) {
comm_timer_delete(pend->timer);
free(pend);
return NULL;
}
/* put at end of waiting list */
if(sq->outnet->udp_wait_last)
sq->outnet->udp_wait_last->next_waiting = pend;
else
sq->outnet->udp_wait_first = pend;
sq->outnet->udp_wait_last = pend;
return pend;
}
log_assert(!sq->busy);
sq->busy = 1;
if(!randomize_and_send_udp(pend, packet, timeout)) {
pending_delete(sq->outnet, pend);
return NULL;
}
sq->busy = 0;
return pend;
}
void
outnet_tcptimer(void* arg)
{
struct waiting_tcp* w = (struct waiting_tcp*)arg;
struct outside_network* outnet = w->outnet;
verbose(VERB_CLIENT, "outnet_tcptimer");
if(w->on_tcp_waiting_list) {
/* it is on the waiting list */
outnet_waiting_tcp_list_remove(outnet, w);
waiting_tcp_callback(w, NULL, NETEVENT_TIMEOUT, NULL);
waiting_tcp_delete(w);
} else {
/* it was in use */
struct pending_tcp* pend=(struct pending_tcp*)w->next_waiting;
reuse_cb_and_decommission(outnet, pend, NETEVENT_TIMEOUT);
}
use_free_buffer(outnet);
}
/** close the oldest reuse_tcp connection to make a fd and struct pend
* available for a new stream connection */
static void
reuse_tcp_close_oldest(struct outside_network* outnet)
{
struct reuse_tcp* reuse;
verbose(VERB_CLIENT, "reuse_tcp_close_oldest");
reuse = reuse_tcp_lru_snip(outnet);
if(!reuse) return;
/* free up */
reuse_cb_and_decommission(outnet, reuse->pending, NETEVENT_CLOSED);
}
static uint16_t
tcp_select_id(struct outside_network* outnet, struct reuse_tcp* reuse)
{
if(reuse)
return reuse_tcp_select_id(reuse, outnet);
return GET_RANDOM_ID(outnet->rnd);
}
/** find spare ID value for reuse tcp stream. That is random and also does
* not collide with an existing query ID that is in use or waiting */
uint16_t
reuse_tcp_select_id(struct reuse_tcp* reuse, struct outside_network* outnet)
{
uint16_t id = 0, curid, nextid;
const int try_random = 2000;
int i;
unsigned select, count, space;
rbnode_type* node;
/* make really sure the tree is not empty */
if(reuse->tree_by_id.count == 0) {
id = GET_RANDOM_ID(outnet->rnd);
return id;
}
/* try to find random empty spots by picking them */
for(i = 0; i<try_random; i++) {
id = GET_RANDOM_ID(outnet->rnd);
if(!reuse_tcp_by_id_find(reuse, id)) {
return id;
}
}
/* equally pick a random unused element from the tree that is
* not in use. Pick a the n-th index of an unused number,
* then loop over the empty spaces in the tree and find it */
log_assert(reuse->tree_by_id.count < 0xffff);
select = ub_random_max(outnet->rnd, 0xffff - reuse->tree_by_id.count);
/* select value now in 0 .. num free - 1 */
count = 0; /* number of free spaces passed by */
node = rbtree_first(&reuse->tree_by_id);
log_assert(node && node != RBTREE_NULL); /* tree not empty */
/* see if select is before first node */
if(select < (unsigned)tree_by_id_get_id(node))
return select;
count += tree_by_id_get_id(node);
/* perhaps select is between nodes */
while(node && node != RBTREE_NULL) {
rbnode_type* next = rbtree_next(node);
if(next && next != RBTREE_NULL) {
curid = tree_by_id_get_id(node);
nextid = tree_by_id_get_id(next);
log_assert(curid < nextid);
if(curid != 0xffff && curid + 1 < nextid) {
/* space between nodes */
space = nextid - curid - 1;
log_assert(select >= count);
if(select < count + space) {
/* here it is */
return curid + 1 + (select - count);
}
count += space;
}
}
node = next;
}
/* select is after the last node */
/* count is the number of free positions before the nodes in the
* tree */
node = rbtree_last(&reuse->tree_by_id);
log_assert(node && node != RBTREE_NULL); /* tree not empty */
curid = tree_by_id_get_id(node);
log_assert(count + (0xffff-curid) + reuse->tree_by_id.count == 0xffff);
return curid + 1 + (select - count);
}
struct waiting_tcp*
pending_tcp_query(struct serviced_query* sq, sldns_buffer* packet,
int timeout, comm_point_callback_type* callback, void* callback_arg)
{
struct pending_tcp* pend = sq->outnet->tcp_free;
struct reuse_tcp* reuse = NULL;
struct waiting_tcp* w;
verbose(VERB_CLIENT, "pending_tcp_query");
if(sldns_buffer_limit(packet) < sizeof(uint16_t)) {
verbose(VERB_ALGO, "pending tcp query with too short buffer < 2");
return NULL;
}
/* find out if a reused stream to the target exists */
/* if so, take it into use */
reuse = reuse_tcp_find(sq->outnet, &sq->addr, sq->addrlen,
sq->ssl_upstream);
if(reuse) {
log_reuse_tcp(VERB_CLIENT, "pending_tcp_query: found reuse", reuse);
log_assert(reuse->pending);
pend = reuse->pending;
reuse_tcp_lru_touch(sq->outnet, reuse);
}
log_assert(!reuse || (reuse && pend));
/* if !pend but we have reuse streams, close a reuse stream
* to be able to open a new one to this target, no use waiting
* to reuse a file descriptor while another query needs to use
* that buffer and file descriptor now. */
if(!pend) {
reuse_tcp_close_oldest(sq->outnet);
pend = sq->outnet->tcp_free;
log_assert(!reuse || (pend == reuse->pending));
}
/* allocate space to store query */
w = (struct waiting_tcp*)malloc(sizeof(struct waiting_tcp)
+ sldns_buffer_limit(packet));
if(!w) {
return NULL;
}
if(!(w->timer = comm_timer_create(sq->outnet->base, outnet_tcptimer, w))) {
free(w);
return NULL;
}
w->pkt = (uint8_t*)w + sizeof(struct waiting_tcp);
w->pkt_len = sldns_buffer_limit(packet);
memmove(w->pkt, sldns_buffer_begin(packet), w->pkt_len);
w->id = tcp_select_id(sq->outnet, reuse);
LDNS_ID_SET(w->pkt, w->id);
memcpy(&w->addr, &sq->addr, sq->addrlen);
w->addrlen = sq->addrlen;
w->outnet = sq->outnet;
w->on_tcp_waiting_list = 0;
w->next_waiting = NULL;
w->cb = callback;
w->cb_arg = callback_arg;
w->ssl_upstream = sq->ssl_upstream;
w->tls_auth_name = sq->tls_auth_name;
w->timeout = timeout;
w->id_node.key = NULL;
w->write_wait_prev = NULL;
w->write_wait_next = NULL;
w->write_wait_queued = 0;
w->error_count = 0;
#ifdef USE_DNSTAP
w->sq = NULL;
#endif
w->in_cb_and_decommission = 0;
if(pend) {
/* we have a buffer available right now */
if(reuse) {
log_assert(reuse == &pend->reuse);
/* reuse existing fd, write query and continue */
/* store query in tree by id */
verbose(VERB_CLIENT, "pending_tcp_query: reuse, store");
w->next_waiting = (void*)pend;
reuse_tree_by_id_insert(&pend->reuse, w);
/* can we write right now? */
if(pend->query == NULL) {
/* write straight away */
/* stop the timer on read of the fd */
comm_point_stop_listening(pend->c);
pend->query = w;
outnet_tcp_take_query_setup(pend->c->fd, pend,
w);
} else {
/* put it in the waiting list for
* this stream */
reuse_write_wait_push_back(&pend->reuse, w);
}
} else {
/* create new fd and connect to addr, setup to
* write query */
verbose(VERB_CLIENT, "pending_tcp_query: new fd, connect");
rbtree_init(&pend->reuse.tree_by_id, reuse_id_cmp);
pend->reuse.pending = pend;
memcpy(&pend->reuse.addr, &sq->addr, sq->addrlen);
pend->reuse.addrlen = sq->addrlen;
if(!outnet_tcp_take_into_use(w)) {
waiting_tcp_delete(w);
return NULL;
}
}
#ifdef USE_DNSTAP
if(sq->outnet->dtenv &&
(sq->outnet->dtenv->log_resolver_query_messages ||
sq->outnet->dtenv->log_forwarder_query_messages)) {
/* use w->pkt, because it has the ID value */
sldns_buffer tmp;
sldns_buffer_init_frm_data(&tmp, w->pkt, w->pkt_len);
dt_msg_send_outside_query(sq->outnet->dtenv, &sq->addr,
&pend->pi->addr, comm_tcp, NULL, sq->zone,
sq->zonelen, &tmp);
}
#endif
} else {
/* queue up */
/* waiting for a buffer on the outside network buffer wait
* list */
verbose(VERB_CLIENT, "pending_tcp_query: queue to wait");
#ifdef USE_DNSTAP
w->sq = sq;
#endif
outnet_waiting_tcp_list_add(sq->outnet, w, 1);
}
return w;
}
/** create query for serviced queries */
static void
serviced_gen_query(sldns_buffer* buff, uint8_t* qname, size_t qnamelen,
uint16_t qtype, uint16_t qclass, uint16_t flags)
{
sldns_buffer_clear(buff);
/* skip id */
sldns_buffer_write_u16(buff, flags);
sldns_buffer_write_u16(buff, 1); /* qdcount */
sldns_buffer_write_u16(buff, 0); /* ancount */
sldns_buffer_write_u16(buff, 0); /* nscount */
sldns_buffer_write_u16(buff, 0); /* arcount */
sldns_buffer_write(buff, qname, qnamelen);
sldns_buffer_write_u16(buff, qtype);
sldns_buffer_write_u16(buff, qclass);
sldns_buffer_flip(buff);
}
/** lookup serviced query in serviced query rbtree */
static struct serviced_query*
lookup_serviced(struct outside_network* outnet, sldns_buffer* buff, int dnssec,
struct sockaddr_storage* addr, socklen_t addrlen,
struct edns_option* opt_list)
{
struct serviced_query key;
key.node.key = &key;
key.qbuf = sldns_buffer_begin(buff);
key.qbuflen = sldns_buffer_limit(buff);
key.dnssec = dnssec;
memcpy(&key.addr, addr, addrlen);
key.addrlen = addrlen;
key.outnet = outnet;
key.opt_list = opt_list;
return (struct serviced_query*)rbtree_search(outnet->serviced, &key);
}
void
serviced_timer_cb(void* arg)
{
struct serviced_query* sq = (struct serviced_query*)arg;
struct outside_network* outnet = sq->outnet;
verbose(VERB_ALGO, "serviced send timer");
/* By the time this cb is called, if we don't have any registered
* callbacks for this serviced_query anymore; do not send. */
if(!sq->cblist)
goto delete;
/* perform first network action */
if(outnet->do_udp && !(sq->tcp_upstream || sq->ssl_upstream)) {
if(!serviced_udp_send(sq, outnet->udp_buff))
goto delete;
} else {
if(!serviced_tcp_send(sq, outnet->udp_buff))
goto delete;
}
/* Maybe by this time we don't have callbacks attached anymore. Don't
* proactively try to delete; let it run and maybe another callback
* will get attached by the time we get an answer. */
return;
delete:
serviced_callbacks(sq, NETEVENT_CLOSED, NULL, NULL);
}
/** Create new serviced entry */
static struct serviced_query*
serviced_create(struct outside_network* outnet, sldns_buffer* buff, int dnssec,
int want_dnssec, int nocaps, int tcp_upstream, int ssl_upstream,
char* tls_auth_name, struct sockaddr_storage* addr, socklen_t addrlen,
uint8_t* zone, size_t zonelen, int qtype, struct edns_option* opt_list,
size_t pad_queries_block_size, struct alloc_cache* alloc,
struct regional* region)
{
struct serviced_query* sq = (struct serviced_query*)malloc(sizeof(*sq));
struct timeval t;
#ifdef UNBOUND_DEBUG
rbnode_type* ins;
#endif
if(!sq) {
alloc_reg_release(alloc, region);
return NULL;
}
sq->node.key = sq;
sq->alloc = alloc;
sq->region = region;
sq->qbuf = regional_alloc_init(region, sldns_buffer_begin(buff),
sldns_buffer_limit(buff));
if(!sq->qbuf) {
alloc_reg_release(alloc, region);
free(sq);
return NULL;
}
sq->qbuflen = sldns_buffer_limit(buff);
sq->zone = regional_alloc_init(region, zone, zonelen);
if(!sq->zone) {
alloc_reg_release(alloc, region);
free(sq);
return NULL;
}
sq->zonelen = zonelen;
sq->qtype = qtype;
sq->dnssec = dnssec;
sq->want_dnssec = want_dnssec;
sq->nocaps = nocaps;
sq->tcp_upstream = tcp_upstream;
sq->ssl_upstream = ssl_upstream;
if(tls_auth_name) {
sq->tls_auth_name = regional_strdup(region, tls_auth_name);
if(!sq->tls_auth_name) {
alloc_reg_release(alloc, region);
free(sq);
return NULL;
}
} else {
sq->tls_auth_name = NULL;
}
memcpy(&sq->addr, addr, addrlen);
sq->addrlen = addrlen;
sq->opt_list = opt_list;
sq->busy = 0;
sq->timer = comm_timer_create(outnet->base, serviced_timer_cb, sq);
if(!sq->timer) {
alloc_reg_release(alloc, region);
free(sq);
return NULL;
}
memset(&t, 0, sizeof(t));
comm_timer_set(sq->timer, &t);
sq->outnet = outnet;
sq->cblist = NULL;
sq->pending = NULL;
sq->status = serviced_initial;
sq->retry = 0;
sq->to_be_deleted = 0;
sq->padding_block_size = pad_queries_block_size;
#ifdef UNBOUND_DEBUG
ins =
#else
(void)
#endif
rbtree_insert(outnet->serviced, &sq->node);
log_assert(ins != NULL); /* must not be already present */
return sq;
}
/** reuse tcp stream, remove serviced query from stream,
* return true if the stream is kept, false if it is to be closed */
static int
reuse_tcp_remove_serviced_keep(struct waiting_tcp* w,
struct serviced_query* sq)
{
struct pending_tcp* pend_tcp = (struct pending_tcp*)w->next_waiting;
verbose(VERB_CLIENT, "reuse_tcp_remove_serviced_keep");
/* remove the callback. let query continue to write to not cancel
* the stream itself. also keep it as an entry in the tree_by_id,
* in case the answer returns (that we no longer want), but we cannot
* pick the same ID number meanwhile */
w->cb = NULL;
/* see if can be entered in reuse tree
* for that the FD has to be non-1 */
if(pend_tcp->c->fd == -1) {
verbose(VERB_CLIENT, "reuse_tcp_remove_serviced_keep: -1 fd");
return 0;
}
/* if in tree and used by other queries */
if(pend_tcp->reuse.node.key) {
verbose(VERB_CLIENT, "reuse_tcp_remove_serviced_keep: in use by other queries");
/* do not reset the keepalive timer, for that
* we'd need traffic, and this is where the serviced is
* removed due to state machine internal reasons,
* eg. iterator no longer interested in this query */
return 1;
}
/* if still open and want to keep it open */
if(pend_tcp->c->fd != -1 && sq->outnet->tcp_reuse.count <
sq->outnet->tcp_reuse_max) {
verbose(VERB_CLIENT, "reuse_tcp_remove_serviced_keep: keep open");
/* set a keepalive timer on it */
if(!reuse_tcp_insert(sq->outnet, pend_tcp)) {
return 0;
}
reuse_tcp_setup_timeout(pend_tcp, sq->outnet->tcp_reuse_timeout);
return 1;
}
return 0;
}
/** cleanup serviced query entry */
static void
serviced_delete(struct serviced_query* sq)
{
verbose(VERB_CLIENT, "serviced_delete");
if(sq->pending) {
/* clear up the pending query */
if(sq->status == serviced_query_UDP_EDNS ||
sq->status == serviced_query_UDP ||
sq->status == serviced_query_UDP_EDNS_FRAG ||
sq->status == serviced_query_UDP_EDNS_fallback) {
struct pending* p = (struct pending*)sq->pending;
verbose(VERB_CLIENT, "serviced_delete: UDP");
if(p->pc)
portcomm_loweruse(sq->outnet, p->pc);
pending_delete(sq->outnet, p);
/* this call can cause reentrant calls back into the
* mesh */
outnet_send_wait_udp(sq->outnet);
} else {
struct waiting_tcp* w = (struct waiting_tcp*)
sq->pending;
verbose(VERB_CLIENT, "serviced_delete: TCP");
log_assert(!(w->write_wait_queued && w->on_tcp_waiting_list));
/* if on stream-write-waiting list then
* remove from waiting list and waiting_tcp_delete */
if(w->write_wait_queued) {
struct pending_tcp* pend =
(struct pending_tcp*)w->next_waiting;
verbose(VERB_CLIENT, "serviced_delete: writewait");
if(!w->in_cb_and_decommission)
reuse_tree_by_id_delete(&pend->reuse, w);
reuse_write_wait_remove(&pend->reuse, w);
if(!w->in_cb_and_decommission)
waiting_tcp_delete(w);
} else if(!w->on_tcp_waiting_list) {
struct pending_tcp* pend =
(struct pending_tcp*)w->next_waiting;
verbose(VERB_CLIENT, "serviced_delete: tcpreusekeep");
/* w needs to stay on tree_by_id to not assign
* the same ID; remove the callback since its
* serviced_query will be gone. */
w->cb = NULL;
if(!reuse_tcp_remove_serviced_keep(w, sq)) {
if(!w->in_cb_and_decommission)
reuse_cb_and_decommission(sq->outnet,
pend, NETEVENT_CLOSED);
use_free_buffer(sq->outnet);
}
sq->pending = NULL;
} else {
verbose(VERB_CLIENT, "serviced_delete: tcpwait");
outnet_waiting_tcp_list_remove(sq->outnet, w);
if(!w->in_cb_and_decommission)
waiting_tcp_delete(w);
}
}
}
/* does not delete from tree, caller has to do that */
serviced_node_del(&sq->node, NULL);
}
/** perturb a dname capitalization randomly */
static void
serviced_perturb_qname(struct ub_randstate* rnd, uint8_t* qbuf, size_t len)
{
uint8_t lablen;
uint8_t* d = qbuf + 10;
long int random = 0;
int bits = 0;
log_assert(len >= 10 + 5 /* offset qname, root, qtype, qclass */);
(void)len;
lablen = *d++;
while(lablen) {
while(lablen--) {
/* only perturb A-Z, a-z */
if(isalpha((unsigned char)*d)) {
/* get a random bit */
if(bits == 0) {
random = ub_random(rnd);
bits = 30;
}
if(random & 0x1) {
*d = (uint8_t)toupper((unsigned char)*d);
} else {
*d = (uint8_t)tolower((unsigned char)*d);
}
random >>= 1;
bits--;
}
d++;
}
lablen = *d++;
}
if(verbosity >= VERB_ALGO) {
char buf[LDNS_MAX_DOMAINLEN+1];
dname_str(qbuf+10, buf);
verbose(VERB_ALGO, "qname perturbed to %s", buf);
}
}
static uint16_t
serviced_query_udp_size(struct serviced_query* sq, enum serviced_query_status status) {
uint16_t udp_size;
if(status == serviced_query_UDP_EDNS_FRAG) {
if(addr_is_ip6(&sq->addr, sq->addrlen)) {
if(EDNS_FRAG_SIZE_IP6 < EDNS_ADVERTISED_SIZE)
udp_size = EDNS_FRAG_SIZE_IP6;
else udp_size = EDNS_ADVERTISED_SIZE;
} else {
if(EDNS_FRAG_SIZE_IP4 < EDNS_ADVERTISED_SIZE)
udp_size = EDNS_FRAG_SIZE_IP4;
else udp_size = EDNS_ADVERTISED_SIZE;
}
} else {
udp_size = EDNS_ADVERTISED_SIZE;
}
return udp_size;
}
/** put serviced query into a buffer */
static void
serviced_encode(struct serviced_query* sq, sldns_buffer* buff, int with_edns)
{
/* if we are using 0x20 bits for ID randomness, perturb them */
if(sq->outnet->use_caps_for_id && !sq->nocaps) {
serviced_perturb_qname(sq->outnet->rnd, sq->qbuf, sq->qbuflen);
}
/* generate query */
sldns_buffer_clear(buff);
sldns_buffer_write_u16(buff, 0); /* id placeholder */
sldns_buffer_write(buff, sq->qbuf, sq->qbuflen);
sldns_buffer_flip(buff);
if(with_edns) {
/* add edns section */
struct edns_data edns;
struct edns_option padding_option;
edns.edns_present = 1;
edns.ext_rcode = 0;
edns.edns_version = EDNS_ADVERTISED_VERSION;
edns.opt_list_in = NULL;
edns.opt_list_out = sq->opt_list;
edns.opt_list_inplace_cb_out = NULL;
edns.udp_size = serviced_query_udp_size(sq, sq->status);
edns.bits = 0;
if(sq->dnssec & EDNS_DO)
edns.bits = EDNS_DO;
if(sq->dnssec & BIT_CD)
LDNS_CD_SET(sldns_buffer_begin(buff));
if (sq->ssl_upstream && sq->padding_block_size) {
padding_option.opt_code = LDNS_EDNS_PADDING;
padding_option.opt_len = 0;
padding_option.opt_data = NULL;
padding_option.next = edns.opt_list_out;
edns.opt_list_out = &padding_option;
edns.padding_block_size = sq->padding_block_size;
}
attach_edns_record(buff, &edns);
}
}
/**
* Perform serviced query UDP sending operation.
* Sends UDP with EDNS, unless infra host marked non EDNS.
* @param sq: query to send.
* @param buff: buffer scratch space.
* @return 0 on error.
*/
static int
serviced_udp_send(struct serviced_query* sq, sldns_buffer* buff)
{
int rtt, vs;
uint8_t edns_lame_known;
time_t now = *sq->outnet->now_secs;
if(!infra_host(sq->outnet->infra, &sq->addr, sq->addrlen, sq->zone,
sq->zonelen, now, &vs, &edns_lame_known, &rtt))
return 0;
sq->last_rtt = rtt;
verbose(VERB_ALGO, "EDNS lookup known=%d vs=%d", edns_lame_known, vs);
if(sq->status == serviced_initial) {
if(vs != -1) {
sq->status = serviced_query_UDP_EDNS;
} else {
sq->status = serviced_query_UDP;
}
}
serviced_encode(sq, buff, (sq->status == serviced_query_UDP_EDNS) ||
(sq->status == serviced_query_UDP_EDNS_FRAG));
sq->last_sent_time = *sq->outnet->now_tv;
sq->edns_lame_known = (int)edns_lame_known;
verbose(VERB_ALGO, "serviced query UDP timeout=%d msec", rtt);
sq->pending = pending_udp_query(sq, buff, rtt,
serviced_udp_callback, sq);
if(!sq->pending)
return 0;
return 1;
}
/** check that perturbed qname is identical */
static int
serviced_check_qname(sldns_buffer* pkt, uint8_t* qbuf, size_t qbuflen)
{
uint8_t* d1 = sldns_buffer_begin(pkt)+12;
uint8_t* d2 = qbuf+10;
uint8_t len1, len2;
int count = 0;
if(sldns_buffer_limit(pkt) < 12+1+4) /* packet too small for qname */
return 0;
log_assert(qbuflen >= 15 /* 10 header, root, type, class */);
len1 = *d1++;
len2 = *d2++;
while(len1 != 0 || len2 != 0) {
if(LABEL_IS_PTR(len1)) {
/* check if we can read *d1 with compression ptr rest */
if(d1 >= sldns_buffer_at(pkt, sldns_buffer_limit(pkt)))
return 0;
d1 = sldns_buffer_begin(pkt)+PTR_OFFSET(len1, *d1);
/* check if we can read the destination *d1 */
if(d1 >= sldns_buffer_at(pkt, sldns_buffer_limit(pkt)))
return 0;
len1 = *d1++;
if(count++ > MAX_COMPRESS_PTRS)
return 0;
continue;
}
if(d2 > qbuf+qbuflen)
return 0;
if(len1 != len2)
return 0;
if(len1 > LDNS_MAX_LABELLEN)
return 0;
/* check len1 + 1(next length) are okay to read */
if(d1+len1 >= sldns_buffer_at(pkt, sldns_buffer_limit(pkt)))
return 0;
log_assert(len1 <= LDNS_MAX_LABELLEN);
log_assert(len2 <= LDNS_MAX_LABELLEN);
log_assert(len1 == len2 && len1 != 0);
/* compare the labels - bitwise identical */
if(memcmp(d1, d2, len1) != 0)
return 0;
d1 += len1;
d2 += len2;
len1 = *d1++;
len2 = *d2++;
}
return 1;
}
/** call the callbacks for a serviced query */
static void
serviced_callbacks(struct serviced_query* sq, int error, struct comm_point* c,
struct comm_reply* rep)
{
struct service_callback* p;
int dobackup = (sq->cblist && sq->cblist->next); /* >1 cb*/
uint8_t *backup_p = NULL;
size_t backlen = 0;
#ifdef UNBOUND_DEBUG
rbnode_type* rem =
#else
(void)
#endif
/* remove from tree, and schedule for deletion, so that callbacks
* can safely deregister themselves and even create new serviced
* queries that are identical to this one. */
rbtree_delete(sq->outnet->serviced, sq);
log_assert(rem); /* should have been present */
sq->to_be_deleted = 1;
verbose(VERB_ALGO, "svcd callbacks start");
if(sq->outnet->use_caps_for_id && error == NETEVENT_NOERROR && c &&
!sq->nocaps && sq->qtype != LDNS_RR_TYPE_PTR) {
/* for type PTR do not check perturbed name in answer,
* compatibility with cisco dns guard boxes that mess up
* reverse queries 0x20 contents */
/* noerror and nxdomain must have a qname in reply */
if(sldns_buffer_read_u16_at(c->buffer, 4) == 0 &&
(LDNS_RCODE_WIRE(sldns_buffer_begin(c->buffer))
== LDNS_RCODE_NOERROR ||
LDNS_RCODE_WIRE(sldns_buffer_begin(c->buffer))
== LDNS_RCODE_NXDOMAIN)) {
verbose(VERB_DETAIL, "no qname in reply to check 0x20ID");
log_addr(VERB_DETAIL, "from server",
&sq->addr, sq->addrlen);
log_buf(VERB_DETAIL, "for packet", c->buffer);
error = NETEVENT_CLOSED;
c = NULL;
} else if(sldns_buffer_read_u16_at(c->buffer, 4) > 0 &&
!serviced_check_qname(c->buffer, sq->qbuf,
sq->qbuflen)) {
verbose(VERB_DETAIL, "wrong 0x20-ID in reply qname");
log_addr(VERB_DETAIL, "from server",
&sq->addr, sq->addrlen);
log_buf(VERB_DETAIL, "for packet", c->buffer);
error = NETEVENT_CAPSFAIL;
/* and cleanup too */
pkt_dname_tolower(c->buffer,
sldns_buffer_at(c->buffer, 12));
} else {
verbose(VERB_ALGO, "good 0x20-ID in reply qname");
/* cleanup caps, prettier cache contents. */
pkt_dname_tolower(c->buffer,
sldns_buffer_at(c->buffer, 12));
}
}
if(dobackup && c) {
/* make a backup of the query, since the querystate processing
* may send outgoing queries that overwrite the buffer.
* use secondary buffer to store the query.
* This is a data copy, but faster than packet to server */
backlen = sldns_buffer_limit(c->buffer);
backup_p = regional_alloc_init(sq->region,
sldns_buffer_begin(c->buffer), backlen);
if(!backup_p) {
log_err("malloc failure in serviced query callbacks");
error = NETEVENT_CLOSED;
c = NULL;
}
sq->outnet->svcd_overhead = backlen;
}
/* test the actual sq->cblist, because the next elem could be deleted*/
while((p=sq->cblist) != NULL) {
sq->cblist = p->next; /* remove this element */
if(dobackup && c) {
sldns_buffer_clear(c->buffer);
sldns_buffer_write(c->buffer, backup_p, backlen);
sldns_buffer_flip(c->buffer);
}
fptr_ok(fptr_whitelist_serviced_query(p->cb));
(void)(*p->cb)(c, p->cb_arg, error, rep);
}
if(backup_p) {
sq->outnet->svcd_overhead = 0;
}
verbose(VERB_ALGO, "svcd callbacks end");
log_assert(sq->cblist == NULL);
serviced_delete(sq);
}
int
serviced_tcp_callback(struct comm_point* c, void* arg, int error,
struct comm_reply* rep)
{
struct serviced_query* sq = (struct serviced_query*)arg;
struct comm_reply r2;
#ifdef USE_DNSTAP
struct waiting_tcp* w = (struct waiting_tcp*)sq->pending;
struct pending_tcp* pend_tcp = NULL;
struct port_if* pi = NULL;
if(w && !w->on_tcp_waiting_list && w->next_waiting) {
pend_tcp = (struct pending_tcp*)w->next_waiting;
pi = pend_tcp->pi;
}
#endif
sq->pending = NULL; /* removed after this callback */
if(error != NETEVENT_NOERROR)
log_addr(VERB_QUERY, "tcp error for address",
&sq->addr, sq->addrlen);
if(error==NETEVENT_NOERROR)
infra_update_tcp_works(sq->outnet->infra, &sq->addr,
sq->addrlen, sq->zone, sq->zonelen);
#ifdef USE_DNSTAP
/*
* sending src (local service)/dst (upstream) addresses over DNSTAP
*/
if(error==NETEVENT_NOERROR && pi && sq->outnet->dtenv &&
(sq->outnet->dtenv->log_resolver_response_messages ||
sq->outnet->dtenv->log_forwarder_response_messages)) {
log_addr(VERB_ALGO, "response from upstream", &sq->addr, sq->addrlen);
log_addr(VERB_ALGO, "to local addr", &pi->addr, pi->addrlen);
dt_msg_send_outside_response(sq->outnet->dtenv, &sq->addr,
&pi->addr, c->type, c->ssl, sq->zone, sq->zonelen, sq->qbuf,
sq->qbuflen, &sq->last_sent_time, sq->outnet->now_tv,
c->buffer);
}
#endif
if(error==NETEVENT_NOERROR && sq->status == serviced_query_TCP_EDNS &&
(LDNS_RCODE_WIRE(sldns_buffer_begin(c->buffer)) ==
LDNS_RCODE_FORMERR || LDNS_RCODE_WIRE(sldns_buffer_begin(
c->buffer)) == LDNS_RCODE_NOTIMPL) ) {
/* attempt to fallback to nonEDNS */
sq->status = serviced_query_TCP_EDNS_fallback;
serviced_tcp_initiate(sq, c->buffer);
return 0;
} else if(error==NETEVENT_NOERROR &&
sq->status == serviced_query_TCP_EDNS_fallback &&
(LDNS_RCODE_WIRE(sldns_buffer_begin(c->buffer)) ==
LDNS_RCODE_NOERROR || LDNS_RCODE_WIRE(
sldns_buffer_begin(c->buffer)) == LDNS_RCODE_NXDOMAIN
|| LDNS_RCODE_WIRE(sldns_buffer_begin(c->buffer))
== LDNS_RCODE_YXDOMAIN)) {
/* the fallback produced a result that looks promising, note
* that this server should be approached without EDNS */
/* only store noEDNS in cache if domain is noDNSSEC */
if(!sq->want_dnssec)
if(!infra_edns_update(sq->outnet->infra, &sq->addr,
sq->addrlen, sq->zone, sq->zonelen, -1,
*sq->outnet->now_secs))
log_err("Out of memory caching no edns for host");
sq->status = serviced_query_TCP;
}
if(sq->tcp_upstream || sq->ssl_upstream) {
struct timeval now = *sq->outnet->now_tv;
if(error!=NETEVENT_NOERROR) {
if(!infra_rtt_update(sq->outnet->infra, &sq->addr,
sq->addrlen, sq->zone, sq->zonelen, sq->qtype,
-1, sq->last_rtt, (time_t)now.tv_sec))
log_err("out of memory in TCP exponential backoff.");
} else if(now.tv_sec > sq->last_sent_time.tv_sec ||
(now.tv_sec == sq->last_sent_time.tv_sec &&
now.tv_usec > sq->last_sent_time.tv_usec)) {
/* convert from microseconds to milliseconds */
int roundtime = ((int)(now.tv_sec - sq->last_sent_time.tv_sec))*1000
+ ((int)now.tv_usec - (int)sq->last_sent_time.tv_usec)/1000;
verbose(VERB_ALGO, "measured TCP-time at %d msec", roundtime);
log_assert(roundtime >= 0);
/* only store if less then AUTH_TIMEOUT seconds, it could be
* huge due to system-hibernated and we woke up */
if(roundtime < 60000) {
if(!infra_rtt_update(sq->outnet->infra, &sq->addr,
sq->addrlen, sq->zone, sq->zonelen, sq->qtype,
roundtime, sq->last_rtt, (time_t)now.tv_sec))
log_err("out of memory noting rtt.");
}
}
}
/* insert address into reply info */
if(!rep) {
/* create one if there isn't (on errors) */
rep = &r2;
r2.c = c;
}
memcpy(&rep->remote_addr, &sq->addr, sq->addrlen);
rep->remote_addrlen = sq->addrlen;
serviced_callbacks(sq, error, c, rep);
return 0;
}
static void
serviced_tcp_initiate(struct serviced_query* sq, sldns_buffer* buff)
{
verbose(VERB_ALGO, "initiate TCP query %s",
sq->status==serviced_query_TCP_EDNS?"EDNS":"");
serviced_encode(sq, buff, sq->status == serviced_query_TCP_EDNS);
sq->last_sent_time = *sq->outnet->now_tv;
log_assert(!sq->busy);
sq->busy = 1;
sq->pending = pending_tcp_query(sq, buff, sq->outnet->tcp_auth_query_timeout,
serviced_tcp_callback, sq);
sq->busy = 0;
if(!sq->pending) {
/* delete from tree so that a retry by above layer does not
* clash with this entry */
verbose(VERB_ALGO, "serviced_tcp_initiate: failed to send tcp query");
serviced_callbacks(sq, NETEVENT_CLOSED, NULL, NULL);
}
}
/** Send serviced query over TCP return false on initial failure */
static int
serviced_tcp_send(struct serviced_query* sq, sldns_buffer* buff)
{
int vs, rtt, timeout;
uint8_t edns_lame_known;
if(!infra_host(sq->outnet->infra, &sq->addr, sq->addrlen, sq->zone,
sq->zonelen, *sq->outnet->now_secs, &vs, &edns_lame_known,
&rtt))
return 0;
sq->last_rtt = rtt;
if(vs != -1)
sq->status = serviced_query_TCP_EDNS;
else sq->status = serviced_query_TCP;
serviced_encode(sq, buff, sq->status == serviced_query_TCP_EDNS);
sq->last_sent_time = *sq->outnet->now_tv;
if(sq->tcp_upstream || sq->ssl_upstream) {
timeout = rtt;
if(rtt >= UNKNOWN_SERVER_NICENESS && rtt < sq->outnet->tcp_auth_query_timeout)
timeout = sq->outnet->tcp_auth_query_timeout;
} else {
timeout = sq->outnet->tcp_auth_query_timeout;
}
log_assert(!sq->busy);
sq->busy = 1;
sq->pending = pending_tcp_query(sq, buff, timeout,
serviced_tcp_callback, sq);
sq->busy = 0;
return sq->pending != NULL;
}
/* see if packet is edns malformed; got zeroes at start.
* This is from servers that return malformed packets to EDNS0 queries,
* but they return good packets for nonEDNS0 queries.
* We try to detect their output; without resorting to a full parse or
* check for too many bytes after the end of the packet. */
static int
packet_edns_malformed(struct sldns_buffer* buf, int qtype)
{
size_t len;
if(sldns_buffer_limit(buf) < LDNS_HEADER_SIZE)
return 1; /* malformed */
/* they have NOERROR rcode, 1 answer. */
if(LDNS_RCODE_WIRE(sldns_buffer_begin(buf)) != LDNS_RCODE_NOERROR)
return 0;
/* one query (to skip) and answer records */
if(LDNS_QDCOUNT(sldns_buffer_begin(buf)) != 1 ||
LDNS_ANCOUNT(sldns_buffer_begin(buf)) == 0)
return 0;
/* skip qname */
len = dname_valid(sldns_buffer_at(buf, LDNS_HEADER_SIZE),
sldns_buffer_limit(buf)-LDNS_HEADER_SIZE);
if(len == 0)
return 0;
if(len == 1 && qtype == 0)
return 0; /* we asked for '.' and type 0 */
/* and then 4 bytes (type and class of query) */
if(sldns_buffer_limit(buf) < LDNS_HEADER_SIZE + len + 4 + 3)
return 0;
/* and start with 11 zeroes as the answer RR */
/* so check the qtype of the answer record, qname=0, type=0 */
if(sldns_buffer_at(buf, LDNS_HEADER_SIZE+len+4)[0] == 0 &&
sldns_buffer_at(buf, LDNS_HEADER_SIZE+len+4)[1] == 0 &&
sldns_buffer_at(buf, LDNS_HEADER_SIZE+len+4)[2] == 0)
return 1;
return 0;
}
int
serviced_udp_callback(struct comm_point* c, void* arg, int error,
struct comm_reply* rep)
{
struct serviced_query* sq = (struct serviced_query*)arg;
struct outside_network* outnet = sq->outnet;
struct timeval now = *sq->outnet->now_tv;
#ifdef USE_DNSTAP
struct pending* p = (struct pending*)sq->pending;
#endif
sq->pending = NULL; /* removed after callback */
if(error == NETEVENT_TIMEOUT) {
if(sq->status == serviced_query_UDP_EDNS && sq->last_rtt < 5000 &&
(serviced_query_udp_size(sq, serviced_query_UDP_EDNS_FRAG) < serviced_query_udp_size(sq, serviced_query_UDP_EDNS))) {
/* fallback to 1480/1280 */
sq->status = serviced_query_UDP_EDNS_FRAG;
log_name_addr(VERB_ALGO, "try edns1xx0", sq->qbuf+10,
&sq->addr, sq->addrlen);
if(!serviced_udp_send(sq, c->buffer)) {
serviced_callbacks(sq, NETEVENT_CLOSED, c, rep);
}
return 0;
}
if(sq->status == serviced_query_UDP_EDNS_FRAG) {
/* fragmentation size did not fix it */
sq->status = serviced_query_UDP_EDNS;
}
sq->retry++;
if(!infra_rtt_update(outnet->infra, &sq->addr, sq->addrlen,
sq->zone, sq->zonelen, sq->qtype, -1, sq->last_rtt,
(time_t)now.tv_sec))
log_err("out of memory in UDP exponential backoff");
if(sq->retry < OUTBOUND_UDP_RETRY) {
log_name_addr(VERB_ALGO, "retry query", sq->qbuf+10,
&sq->addr, sq->addrlen);
if(!serviced_udp_send(sq, c->buffer)) {
serviced_callbacks(sq, NETEVENT_CLOSED, c, rep);
}
return 0;
}
}
if(error != NETEVENT_NOERROR) {
/* udp returns error (due to no ID or interface available) */
serviced_callbacks(sq, error, c, rep);
return 0;
}
#ifdef USE_DNSTAP
/*
* sending src (local service)/dst (upstream) addresses over DNSTAP
*/
if(error == NETEVENT_NOERROR && outnet->dtenv && p->pc &&
(outnet->dtenv->log_resolver_response_messages ||
outnet->dtenv->log_forwarder_response_messages)) {
log_addr(VERB_ALGO, "response from upstream", &sq->addr, sq->addrlen);
log_addr(VERB_ALGO, "to local addr", &p->pc->pif->addr,
p->pc->pif->addrlen);
dt_msg_send_outside_response(outnet->dtenv, &sq->addr,
&p->pc->pif->addr, c->type, c->ssl, sq->zone, sq->zonelen,
sq->qbuf, sq->qbuflen, &sq->last_sent_time,
sq->outnet->now_tv, c->buffer);
}
#endif
if( (sq->status == serviced_query_UDP_EDNS
||sq->status == serviced_query_UDP_EDNS_FRAG)
&& (LDNS_RCODE_WIRE(sldns_buffer_begin(c->buffer))
== LDNS_RCODE_FORMERR || LDNS_RCODE_WIRE(
sldns_buffer_begin(c->buffer)) == LDNS_RCODE_NOTIMPL
|| packet_edns_malformed(c->buffer, sq->qtype)
)) {
/* try to get an answer by falling back without EDNS */
verbose(VERB_ALGO, "serviced query: attempt without EDNS");
sq->status = serviced_query_UDP_EDNS_fallback;
sq->retry = 0;
if(!serviced_udp_send(sq, c->buffer)) {
serviced_callbacks(sq, NETEVENT_CLOSED, c, rep);
}
return 0;
} else if(sq->status == serviced_query_UDP_EDNS &&
!sq->edns_lame_known) {
/* now we know that edns queries received answers store that */
log_addr(VERB_ALGO, "serviced query: EDNS works for",
&sq->addr, sq->addrlen);
if(!infra_edns_update(outnet->infra, &sq->addr, sq->addrlen,
sq->zone, sq->zonelen, 0, (time_t)now.tv_sec)) {
log_err("Out of memory caching edns works");
}
sq->edns_lame_known = 1;
} else if(sq->status == serviced_query_UDP_EDNS_fallback &&
!sq->edns_lame_known && (LDNS_RCODE_WIRE(
sldns_buffer_begin(c->buffer)) == LDNS_RCODE_NOERROR ||
LDNS_RCODE_WIRE(sldns_buffer_begin(c->buffer)) ==
LDNS_RCODE_NXDOMAIN || LDNS_RCODE_WIRE(sldns_buffer_begin(
c->buffer)) == LDNS_RCODE_YXDOMAIN)) {
/* the fallback produced a result that looks promising, note
* that this server should be approached without EDNS */
/* only store noEDNS in cache if domain is noDNSSEC */
if(!sq->want_dnssec) {
log_addr(VERB_ALGO, "serviced query: EDNS fails for",
&sq->addr, sq->addrlen);
if(!infra_edns_update(outnet->infra, &sq->addr, sq->addrlen,
sq->zone, sq->zonelen, -1, (time_t)now.tv_sec)) {
log_err("Out of memory caching no edns for host");
}
} else {
log_addr(VERB_ALGO, "serviced query: EDNS fails, but "
"not stored because need DNSSEC for", &sq->addr,
sq->addrlen);
}
sq->status = serviced_query_UDP;
}
if(now.tv_sec > sq->last_sent_time.tv_sec ||
(now.tv_sec == sq->last_sent_time.tv_sec &&
now.tv_usec > sq->last_sent_time.tv_usec)) {
/* convert from microseconds to milliseconds */
int roundtime = ((int)(now.tv_sec - sq->last_sent_time.tv_sec))*1000
+ ((int)now.tv_usec - (int)sq->last_sent_time.tv_usec)/1000;
verbose(VERB_ALGO, "measured roundtrip at %d msec", roundtime);
log_assert(roundtime >= 0);
/* in case the system hibernated, do not enter a huge value,
* above this value gives trouble with server selection */
if(roundtime < 60000) {
if(!infra_rtt_update(outnet->infra, &sq->addr, sq->addrlen,
sq->zone, sq->zonelen, sq->qtype, roundtime,
sq->last_rtt, (time_t)now.tv_sec))
log_err("out of memory noting rtt.");
}
}
/* perform TC flag check and TCP fallback after updating our
* cache entries for EDNS status and RTT times */
if(LDNS_TC_WIRE(sldns_buffer_begin(c->buffer))) {
/* fallback to TCP */
/* this discards partial UDP contents */
if(sq->status == serviced_query_UDP_EDNS ||
sq->status == serviced_query_UDP_EDNS_FRAG ||
sq->status == serviced_query_UDP_EDNS_fallback)
/* if we have unfinished EDNS_fallback, start again */
sq->status = serviced_query_TCP_EDNS;
else sq->status = serviced_query_TCP;
serviced_tcp_initiate(sq, c->buffer);
return 0;
}
/* yay! an answer */
serviced_callbacks(sq, error, c, rep);
return 0;
}
struct serviced_query*
outnet_serviced_query(struct outside_network* outnet,
struct query_info* qinfo, uint16_t flags, int dnssec, int want_dnssec,
int nocaps, int check_ratelimit, int tcp_upstream, int ssl_upstream,
char* tls_auth_name, struct sockaddr_storage* addr, socklen_t addrlen,
uint8_t* zone, size_t zonelen, struct module_qstate* qstate,
comm_point_callback_type* callback, void* callback_arg,
sldns_buffer* buff, struct module_env* env, int* was_ratelimited)
{
struct serviced_query* sq;
struct service_callback* cb;
struct edns_string_addr* client_string_addr;
struct regional* region;
struct edns_option* backed_up_opt_list = qstate->edns_opts_back_out;
struct edns_option* per_upstream_opt_list = NULL;
time_t timenow = 0;
/* If we have an already populated EDNS option list make a copy since
* we may now add upstream specific EDNS options. */
/* Use a region that could be attached to a serviced_query, if it needs
* to be created. If an existing one is found then this region will be
* destroyed here. */
region = alloc_reg_obtain(env->alloc);
if(!region) return NULL;
if(qstate->edns_opts_back_out) {
per_upstream_opt_list = edns_opt_copy_region(
qstate->edns_opts_back_out, region);
if(!per_upstream_opt_list) {
alloc_reg_release(env->alloc, region);
return NULL;
}
qstate->edns_opts_back_out = per_upstream_opt_list;
}
if(!inplace_cb_query_call(env, qinfo, flags, addr, addrlen, zone,
zonelen, qstate, region)) {
alloc_reg_release(env->alloc, region);
return NULL;
}
/* Restore the option list; we can explicitly use the copied one from
* now on. */
per_upstream_opt_list = qstate->edns_opts_back_out;
qstate->edns_opts_back_out = backed_up_opt_list;
if((client_string_addr = edns_string_addr_lookup(
&env->edns_strings->client_strings, addr, addrlen))) {
edns_opt_list_append(&per_upstream_opt_list,
env->edns_strings->client_string_opcode,
client_string_addr->string_len,
client_string_addr->string, region);
}
serviced_gen_query(buff, qinfo->qname, qinfo->qname_len, qinfo->qtype,
qinfo->qclass, flags);
sq = lookup_serviced(outnet, buff, dnssec, addr, addrlen,
per_upstream_opt_list);
if(!sq) {
/* Check ratelimit only for new serviced_query */
if(check_ratelimit) {
timenow = *env->now;
if(!infra_ratelimit_inc(env->infra_cache, zone,
zonelen, timenow, env->cfg->ratelimit_backoff,
&qstate->qinfo, qstate->reply)) {
/* Can we pass through with slip factor? */
if(env->cfg->ratelimit_factor == 0 ||
ub_random_max(env->rnd,
env->cfg->ratelimit_factor) != 1) {
*was_ratelimited = 1;
alloc_reg_release(env->alloc, region);
return NULL;
}
log_nametypeclass(VERB_ALGO,
"ratelimit allowed through for "
"delegation point", zone,
LDNS_RR_TYPE_NS, LDNS_RR_CLASS_IN);
}
}
/* make new serviced query entry */
sq = serviced_create(outnet, buff, dnssec, want_dnssec, nocaps,
tcp_upstream, ssl_upstream, tls_auth_name, addr,
addrlen, zone, zonelen, (int)qinfo->qtype,
per_upstream_opt_list,
( ssl_upstream && env->cfg->pad_queries
? env->cfg->pad_queries_block_size : 0 ),
env->alloc, region);
if(!sq) {
if(check_ratelimit) {
infra_ratelimit_dec(env->infra_cache,
zone, zonelen, timenow);
}
return NULL;
}
if(!(cb = (struct service_callback*)regional_alloc(
sq->region, sizeof(*cb)))) {
if(check_ratelimit) {
infra_ratelimit_dec(env->infra_cache,
zone, zonelen, timenow);
}
(void)rbtree_delete(outnet->serviced, sq);
serviced_node_del(&sq->node, NULL);
return NULL;
}
/* No network action at this point; it will be invoked with the
* serviced_query timer instead to run outside of the mesh. */
} else {
/* We don't need this region anymore. */
alloc_reg_release(env->alloc, region);
/* duplicate entries are included in the callback list, because
* there is a counterpart registration by our caller that needs
* to be doubly-removed (with callbacks perhaps). */
if(!(cb = (struct service_callback*)regional_alloc(
sq->region, sizeof(*cb)))) {
return NULL;
}
}
/* add callback to list of callbacks */
cb->cb = callback;
cb->cb_arg = callback_arg;
cb->next = sq->cblist;
sq->cblist = cb;
return sq;
}
/** remove callback from list */
static void
callback_list_remove(struct serviced_query* sq, void* cb_arg)
{
struct service_callback** pp = &sq->cblist;
while(*pp) {
if((*pp)->cb_arg == cb_arg) {
struct service_callback* del = *pp;
*pp = del->next;
return;
}
pp = &(*pp)->next;
}
}
void outnet_serviced_query_stop(struct serviced_query* sq, void* cb_arg)
{
if(!sq)
return;
callback_list_remove(sq, cb_arg);
/* if callbacks() routine scheduled deletion, let it do that */
if(!sq->cblist && !sq->busy && !sq->to_be_deleted) {
(void)rbtree_delete(sq->outnet->serviced, sq);
serviced_delete(sq);
}
}
/** create fd to send to this destination */
static int
fd_for_dest(struct outside_network* outnet, struct sockaddr_storage* to_addr,
socklen_t to_addrlen)
{
struct sockaddr_storage* addr;
socklen_t addrlen;
int i, try, pnum, dscp;
struct port_if* pif;
/* create fd */
dscp = outnet->ip_dscp;
for(try = 0; try<1000; try++) {
int port = 0;
int freebind = 0;
int noproto = 0;
int inuse = 0;
int fd = -1;
/* select interface */
if(addr_is_ip6(to_addr, to_addrlen)) {
if(outnet->num_ip6 == 0) {
char to[64];
addr_to_str(to_addr, to_addrlen, to, sizeof(to));
verbose(VERB_QUERY, "need ipv6 to send, but no ipv6 outgoing interfaces, for %s", to);
return -1;
}
i = ub_random_max(outnet->rnd, outnet->num_ip6);
pif = &outnet->ip6_ifs[i];
} else {
if(outnet->num_ip4 == 0) {
char to[64];
addr_to_str(to_addr, to_addrlen, to, sizeof(to));
verbose(VERB_QUERY, "need ipv4 to send, but no ipv4 outgoing interfaces, for %s", to);
return -1;
}
i = ub_random_max(outnet->rnd, outnet->num_ip4);
pif = &outnet->ip4_ifs[i];
}
addr = &pif->addr;
addrlen = pif->addrlen;
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
pnum = ub_random_max(outnet->rnd, pif->avail_total);
if(pnum < pif->inuse) {
/* port already open */
port = pif->out[pnum]->number;
} else {
/* unused ports in start part of array */
port = pif->avail_ports[pnum - pif->inuse];
}
#else
pnum = port = 0;
#endif
if(addr_is_ip6(to_addr, to_addrlen)) {
struct sockaddr_in6 sa = *(struct sockaddr_in6*)addr;
sa.sin6_port = (in_port_t)htons((uint16_t)port);
fd = create_udp_sock(AF_INET6, SOCK_DGRAM,
(struct sockaddr*)&sa, addrlen, 1, &inuse, &noproto,
0, 0, 0, NULL, 0, freebind, 0, dscp);
} else {
struct sockaddr_in* sa = (struct sockaddr_in*)addr;
sa->sin_port = (in_port_t)htons((uint16_t)port);
fd = create_udp_sock(AF_INET, SOCK_DGRAM,
(struct sockaddr*)addr, addrlen, 1, &inuse, &noproto,
0, 0, 0, NULL, 0, freebind, 0, dscp);
}
if(fd != -1) {
return fd;
}
if(!inuse) {
return -1;
}
}
/* too many tries */
log_err("cannot send probe, ports are in use");
return -1;
}
struct comm_point*
outnet_comm_point_for_udp(struct outside_network* outnet,
comm_point_callback_type* cb, void* cb_arg,
struct sockaddr_storage* to_addr, socklen_t to_addrlen)
{
struct comm_point* cp;
int fd = fd_for_dest(outnet, to_addr, to_addrlen);
if(fd == -1) {
return NULL;
}
cp = comm_point_create_udp(outnet->base, fd, outnet->udp_buff, 0,
cb, cb_arg, NULL);
if(!cp) {
log_err("malloc failure");
close(fd);
return NULL;
}
return cp;
}
/** setup SSL for comm point */
static int
setup_comm_ssl(struct comm_point* cp, struct outside_network* outnet,
int fd, char* host)
{
cp->ssl = outgoing_ssl_fd(outnet->sslctx, fd);
if(!cp->ssl) {
log_err("cannot create SSL object");
return 0;
}
#ifdef USE_WINSOCK
comm_point_tcp_win_bio_cb(cp, cp->ssl);
#endif
cp->ssl_shake_state = comm_ssl_shake_write;
/* https verification */
#ifdef HAVE_SSL
if(outnet->tls_use_sni) {
(void)SSL_set_tlsext_host_name(cp->ssl, host);
}
#endif
#ifdef HAVE_SSL_SET1_HOST
if((SSL_CTX_get_verify_mode(outnet->sslctx)&SSL_VERIFY_PEER)) {
/* because we set SSL_VERIFY_PEER, in netevent in
* ssl_handshake, it'll check if the certificate
* verification has succeeded */
/* SSL_VERIFY_PEER is set on the sslctx */
/* and the certificates to verify with are loaded into
* it with SSL_load_verify_locations or
* SSL_CTX_set_default_verify_paths */
/* setting the hostname makes openssl verify the
* host name in the x509 certificate in the
* SSL connection*/
if(!SSL_set1_host(cp->ssl, host)) {
log_err("SSL_set1_host failed");
return 0;
}
}
#elif defined(HAVE_X509_VERIFY_PARAM_SET1_HOST)
/* openssl 1.0.2 has this function that can be used for
* set1_host like verification */
if((SSL_CTX_get_verify_mode(outnet->sslctx)&SSL_VERIFY_PEER)) {
X509_VERIFY_PARAM* param = SSL_get0_param(cp->ssl);
# ifdef X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS
X509_VERIFY_PARAM_set_hostflags(param, X509_CHECK_FLAG_NO_PARTIAL_WILDCARDS);
# endif
if(!X509_VERIFY_PARAM_set1_host(param, host, strlen(host))) {
log_err("X509_VERIFY_PARAM_set1_host failed");
return 0;
}
}
#else
(void)host;
#endif /* HAVE_SSL_SET1_HOST */
return 1;
}
struct comm_point*
outnet_comm_point_for_tcp(struct outside_network* outnet,
comm_point_callback_type* cb, void* cb_arg,
struct sockaddr_storage* to_addr, socklen_t to_addrlen,
sldns_buffer* query, int timeout, int ssl, char* host)
{
struct comm_point* cp;
int fd = outnet_get_tcp_fd(to_addr, to_addrlen, outnet->tcp_mss, outnet->ip_dscp);
if(fd == -1) {
return 0;
}
fd_set_nonblock(fd);
if(!outnet_tcp_connect(fd, to_addr, to_addrlen)) {
/* outnet_tcp_connect has closed fd on error for us */
return 0;
}
cp = comm_point_create_tcp_out(outnet->base, 65552, cb, cb_arg);
if(!cp) {
log_err("malloc failure");
close(fd);
return 0;
}
cp->repinfo.remote_addrlen = to_addrlen;
memcpy(&cp->repinfo.remote_addr, to_addr, to_addrlen);
/* setup for SSL (if needed) */
if(ssl) {
if(!setup_comm_ssl(cp, outnet, fd, host)) {
log_err("cannot setup XoT");
comm_point_delete(cp);
return NULL;
}
}
/* set timeout on TCP connection */
comm_point_start_listening(cp, fd, timeout);
/* copy scratch buffer to cp->buffer */
sldns_buffer_copy(cp->buffer, query);
return cp;
}
/** setup the User-Agent HTTP header based on http-user-agent configuration */
static void
setup_http_user_agent(sldns_buffer* buf, struct config_file* cfg)
{
if(cfg->hide_http_user_agent) return;
if(cfg->http_user_agent==NULL || cfg->http_user_agent[0] == 0) {
sldns_buffer_printf(buf, "User-Agent: %s/%s\r\n", PACKAGE_NAME,
PACKAGE_VERSION);
} else {
sldns_buffer_printf(buf, "User-Agent: %s\r\n", cfg->http_user_agent);
}
}
/** setup http request headers in buffer for sending query to destination */
static int
setup_http_request(sldns_buffer* buf, char* host, char* path,
struct config_file* cfg)
{
sldns_buffer_clear(buf);
sldns_buffer_printf(buf, "GET /%s HTTP/1.1\r\n", path);
sldns_buffer_printf(buf, "Host: %s\r\n", host);
setup_http_user_agent(buf, cfg);
/* We do not really do multiple queries per connection,
* but this header setting is also not needed.
* sldns_buffer_printf(buf, "Connection: close\r\n") */
sldns_buffer_printf(buf, "\r\n");
if(sldns_buffer_position(buf)+10 > sldns_buffer_capacity(buf))
return 0; /* somehow buffer too short, but it is about 60K
and the request is only a couple bytes long. */
sldns_buffer_flip(buf);
return 1;
}
struct comm_point*
outnet_comm_point_for_http(struct outside_network* outnet,
comm_point_callback_type* cb, void* cb_arg,
struct sockaddr_storage* to_addr, socklen_t to_addrlen, int timeout,
int ssl, char* host, char* path, struct config_file* cfg)
{
/* cp calls cb with err=NETEVENT_DONE when transfer is done */
struct comm_point* cp;
int fd = outnet_get_tcp_fd(to_addr, to_addrlen, outnet->tcp_mss, outnet->ip_dscp);
if(fd == -1) {
return 0;
}
fd_set_nonblock(fd);
if(!outnet_tcp_connect(fd, to_addr, to_addrlen)) {
/* outnet_tcp_connect has closed fd on error for us */
return 0;
}
cp = comm_point_create_http_out(outnet->base, 65552, cb, cb_arg,
outnet->udp_buff);
if(!cp) {
log_err("malloc failure");
close(fd);
return 0;
}
cp->repinfo.remote_addrlen = to_addrlen;
memcpy(&cp->repinfo.remote_addr, to_addr, to_addrlen);
/* setup for SSL (if needed) */
if(ssl) {
if(!setup_comm_ssl(cp, outnet, fd, host)) {
log_err("cannot setup https");
comm_point_delete(cp);
return NULL;
}
}
/* set timeout on TCP connection */
comm_point_start_listening(cp, fd, timeout);
/* setup http request in cp->buffer */
if(!setup_http_request(cp->buffer, host, path, cfg)) {
log_err("error setting up http request");
comm_point_delete(cp);
return NULL;
}
return cp;
}
/** get memory used by waiting tcp entry (in use or not) */
static size_t
waiting_tcp_get_mem(struct waiting_tcp* w)
{
size_t s;
if(!w) return 0;
s = sizeof(*w) + w->pkt_len;
if(w->timer)
s += comm_timer_get_mem(w->timer);
return s;
}
/** get memory used by port if */
static size_t
if_get_mem(struct port_if* pif)
{
size_t s;
int i;
s = sizeof(*pif) +
#ifndef DISABLE_EXPLICIT_PORT_RANDOMISATION
sizeof(int)*pif->avail_total +
#endif
sizeof(struct port_comm*)*pif->maxout;
for(i=0; i<pif->inuse; i++)
s += sizeof(*pif->out[i]) +
comm_point_get_mem(pif->out[i]->cp);
return s;
}
/** get memory used by waiting udp */
static size_t
waiting_udp_get_mem(struct pending* w)
{
size_t s;
s = sizeof(*w) + comm_timer_get_mem(w->timer) + w->pkt_len;
return s;
}
size_t outnet_get_mem(struct outside_network* outnet)
{
size_t i;
int k;
struct waiting_tcp* w;
struct pending* u;
struct serviced_query* sq;
struct service_callback* sb;
struct port_comm* pc;
size_t s = sizeof(*outnet) + sizeof(*outnet->base) +
sizeof(*outnet->udp_buff) +
sldns_buffer_capacity(outnet->udp_buff);
/* second buffer is not ours */
for(pc = outnet->unused_fds; pc; pc = pc->next) {
s += sizeof(*pc) + comm_point_get_mem(pc->cp);
}
for(k=0; k<outnet->num_ip4; k++)
s += if_get_mem(&outnet->ip4_ifs[k]);
for(k=0; k<outnet->num_ip6; k++)
s += if_get_mem(&outnet->ip6_ifs[k]);
for(u=outnet->udp_wait_first; u; u=u->next_waiting)
s += waiting_udp_get_mem(u);
s += sizeof(struct pending_tcp*)*outnet->num_tcp;
for(i=0; i<outnet->num_tcp; i++) {
s += sizeof(struct pending_tcp);
s += comm_point_get_mem(outnet->tcp_conns[i]->c);
if(outnet->tcp_conns[i]->query)
s += waiting_tcp_get_mem(outnet->tcp_conns[i]->query);
}
for(w=outnet->tcp_wait_first; w; w = w->next_waiting)
s += waiting_tcp_get_mem(w);
s += sizeof(*outnet->pending);
s += (sizeof(struct pending) + comm_timer_get_mem(NULL)) *
outnet->pending->count;
s += sizeof(*outnet->serviced);
s += outnet->svcd_overhead;
RBTREE_FOR(sq, struct serviced_query*, outnet->serviced) {
s += sizeof(*sq) + sq->qbuflen;
for(sb = sq->cblist; sb; sb = sb->next)
s += sizeof(*sb);
}
return s;
}
size_t
serviced_get_mem(struct serviced_query* sq)
{
struct service_callback* sb;
size_t s;
s = sizeof(*sq) + sq->qbuflen;
for(sb = sq->cblist; sb; sb = sb->next)
s += sizeof(*sb);
if(sq->status == serviced_query_UDP_EDNS ||
sq->status == serviced_query_UDP ||
sq->status == serviced_query_UDP_EDNS_FRAG ||
sq->status == serviced_query_UDP_EDNS_fallback) {
s += sizeof(struct pending);
s += comm_timer_get_mem(NULL);
} else {
/* does not have size of the pkt pointer */
/* always has a timer except on malloc failures */
/* these sizes are part of the main outside network mem */
/*
s += sizeof(struct waiting_tcp);
s += comm_timer_get_mem(NULL);
*/
}
return s;
}