/*
* testcode/delayer.c - debug program that delays queries to a server.
*
* Copyright (c) 2008, 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 program delays queries made. It performs as a proxy to another
* server and delays queries to it.
*/
#include "config.h"
#ifdef HAVE_GETOPT_H
#include <getopt.h>
#endif
#ifdef HAVE_TIME_H
#include <time.h>
#endif
#include <sys/time.h>
#include "util/net_help.h"
#include "util/config_file.h"
#include "sldns/sbuffer.h"
#include <signal.h>
/** number of reads per select for delayer */
#define TRIES_PER_SELECT 100
/**
* The ring buffer
*/
struct ringbuf {
/** base of buffer */
uint8_t* buf;
/** size of buffer */
size_t size;
/** low mark, items start here */
size_t low;
/** high mark, items end here */
size_t high;
};
/**
* List of proxy fds that return replies from the server to our clients.
*/
struct proxy {
/** the fd to listen for replies from server */
int s;
/** last time this was used */
struct timeval lastuse;
/** remote address */
struct sockaddr_storage addr;
/** length of addr */
socklen_t addr_len;
/** number of queries waiting (in total) */
size_t numwait;
/** number of queries sent to server (in total) */
size_t numsent;
/** numberof answers returned to client (in total) */
size_t numreturn;
/** how many times repurposed */
size_t numreuse;
/** next in proxylist */
struct proxy* next;
};
/**
* An item that has to be TCP relayed
*/
struct tcp_send_list {
/** the data item */
uint8_t* item;
/** size of item */
size_t len;
/** time when the item can be transmitted on */
struct timeval wait;
/** how much of the item has already been transmitted */
size_t done;
/** next in list */
struct tcp_send_list* next;
};
/**
* List of TCP proxy fd pairs to TCP connect client to server
*/
struct tcp_proxy {
/** the fd to listen for client query */
int client_s;
/** the fd to listen for server answer */
int server_s;
/** remote client address */
struct sockaddr_storage addr;
/** length of address */
socklen_t addr_len;
/** timeout on this entry */
struct timeval timeout;
/** list of query items to send to server */
struct tcp_send_list* querylist;
/** last in query list */
struct tcp_send_list* querylast;
/** list of answer items to send to client */
struct tcp_send_list* answerlist;
/** last in answerlist */
struct tcp_send_list* answerlast;
/** next in list */
struct tcp_proxy* next;
};
/** usage information for delayer */
static void usage(char* argv[])
{
printf("usage: %s [options]\n", argv[0]);
printf(" -f addr : use addr, forward to that server, @port.\n");
printf(" -b addr : bind to this address to listen.\n");
printf(" -p port : bind to this port (use 0 for random).\n");
printf(" -m mem : use this much memory for waiting queries.\n");
printf(" -d delay: UDP queries are delayed n milliseconds.\n");
printf(" TCP is delayed twice (on send, on recv).\n");
printf(" -h : this help message\n");
exit(1);
}
/** timeval compare, t1 < t2 */
static int
dl_tv_smaller(struct timeval* t1, const struct timeval* t2)
{
#ifndef S_SPLINT_S
if(t1->tv_sec < t2->tv_sec)
return 1;
if(t1->tv_sec == t2->tv_sec &&
t1->tv_usec < t2->tv_usec)
return 1;
#endif
return 0;
}
/** timeval add, t1 += t2 */
static void
dl_tv_add(struct timeval* t1, const struct timeval* t2)
{
#ifndef S_SPLINT_S
t1->tv_sec += t2->tv_sec;
t1->tv_usec += t2->tv_usec;
while(t1->tv_usec > 1000000) {
t1->tv_usec -= 1000000;
t1->tv_sec++;
}
#endif
}
/** timeval subtract, t1 -= t2 */
static void
dl_tv_subtract(struct timeval* t1, const struct timeval* t2)
{
#ifndef S_SPLINT_S
t1->tv_sec -= t2->tv_sec;
if(t1->tv_usec >= t2->tv_usec) {
t1->tv_usec -= t2->tv_usec;
} else {
t1->tv_sec--;
t1->tv_usec = 1000000-(t2->tv_usec-t1->tv_usec);
}
#endif
}
/** create new ring buffer */
static struct ringbuf*
ring_create(size_t sz)
{
struct ringbuf* r = (struct ringbuf*)calloc(1, sizeof(*r));
if(!r) fatal_exit("out of memory");
r->buf = (uint8_t*)malloc(sz);
if(!r->buf) fatal_exit("out of memory");
r->size = sz;
r->low = 0;
r->high = 0;
return r;
}
/** delete ring buffer */
static void
ring_delete(struct ringbuf* r)
{
if(!r) return;
free(r->buf);
free(r);
}
/** add entry to ringbuffer */
static void
ring_add(struct ringbuf* r, sldns_buffer* pkt, struct timeval* now,
struct timeval* delay, struct proxy* p)
{
/* time -- proxy* -- 16bitlen -- message */
uint16_t len = (uint16_t)sldns_buffer_limit(pkt);
struct timeval when;
size_t needed;
uint8_t* where = NULL;
log_assert(sldns_buffer_limit(pkt) <= 65535);
needed = sizeof(when) + sizeof(p) + sizeof(len) + len;
/* put item into ringbuffer */
if(r->low < r->high) {
/* used part is in the middle */
if(r->size - r->high >= needed) {
where = r->buf + r->high;
r->high += needed;
} else if(r->low > needed) {
/* wrap around ringbuffer */
/* make sure r->low == r->high means empty */
/* so r->low == r->high cannot be used to signify
* a completely full ringbuf */
if(r->size - r->high > sizeof(when)+sizeof(p)) {
/* zero entry at end of buffer */
memset(r->buf+r->high, 0,
sizeof(when)+sizeof(p));
}
where = r->buf;
r->high = needed;
} else {
/* drop message */
log_warn("warning: mem full, dropped message");
return;
}
} else {
/* empty */
if(r->high == r->low) {
where = r->buf;
r->low = 0;
r->high = needed;
/* unused part is in the middle */
/* so ringbuffer has wrapped around */
} else if(r->low - r->high > needed) {
where = r->buf + r->high;
r->high += needed;
} else {
log_warn("warning: mem full, dropped message");
return;
}
}
when = *now;
dl_tv_add(&when, delay);
/* copy it at where part */
log_assert(where != NULL);
memmove(where, &when, sizeof(when));
memmove(where+sizeof(when), &p, sizeof(p));
memmove(where+sizeof(when)+sizeof(p), &len, sizeof(len));
memmove(where+sizeof(when)+sizeof(p)+sizeof(len),
sldns_buffer_begin(pkt), len);
}
/** see if the ringbuffer is empty */
static int
ring_empty(struct ringbuf* r)
{
return (r->low == r->high);
}
/** peek at timevalue for next item in ring */
static struct timeval*
ring_peek_time(struct ringbuf* r)
{
if(ring_empty(r))
return NULL;
return (struct timeval*)&r->buf[r->low];
}
/** get entry from ringbuffer */
static int
ring_pop(struct ringbuf* r, sldns_buffer* pkt, struct timeval* tv,
struct proxy** p)
{
/* time -- proxy* -- 16bitlen -- message */
uint16_t len;
uint8_t* where = NULL;
size_t done;
if(r->low == r->high)
return 0;
where = r->buf + r->low;
memmove(tv, where, sizeof(*tv));
memmove(p, where+sizeof(*tv), sizeof(*p));
memmove(&len, where+sizeof(*tv)+sizeof(*p), sizeof(len));
memmove(sldns_buffer_begin(pkt),
where+sizeof(*tv)+sizeof(*p)+sizeof(len), len);
sldns_buffer_set_limit(pkt, (size_t)len);
done = sizeof(*tv)+sizeof(*p)+sizeof(len)+len;
/* move lowmark */
if(r->low < r->high) {
/* used part in middle */
log_assert(r->high - r->low >= done);
r->low += done;
} else {
/* unused part in middle */
log_assert(r->size - r->low >= done);
r->low += done;
if(r->size - r->low > sizeof(*tv)+sizeof(*p)) {
/* see if it is zeroed; means end of buffer */
struct proxy* pz;
memmove(&pz, r->buf+r->low+sizeof(*tv), sizeof(pz));
if(pz == NULL)
r->low = 0;
} else r->low = 0;
}
if(r->low == r->high) {
r->low = 0; /* reset if empty */
r->high = 0;
}
return 1;
}
/** signal handler global info */
static volatile int do_quit = 0;
/** signal handler for user quit */
static RETSIGTYPE delayer_sigh(int sig)
{
printf("exit on signal %d\n", sig);
do_quit = 1;
}
/** send out waiting packets */
static void
service_send(struct ringbuf* ring, struct timeval* now, sldns_buffer* pkt,
struct sockaddr_storage* srv_addr, socklen_t srv_len)
{
struct proxy* p;
struct timeval tv;
ssize_t sent;
while(!ring_empty(ring) &&
dl_tv_smaller(ring_peek_time(ring), now)) {
/* this items needs to be sent out */
if(!ring_pop(ring, pkt, &tv, &p))
fatal_exit("ringbuf error: pop failed");
verbose(1, "send out query %d.%6.6d",
(unsigned)tv.tv_sec, (unsigned)tv.tv_usec);
log_addr(1, "from client", &p->addr, p->addr_len);
/* send it */
sent = sendto(p->s, (void*)sldns_buffer_begin(pkt),
sldns_buffer_limit(pkt), 0,
(struct sockaddr*)srv_addr, srv_len);
if(sent == -1) {
#ifndef USE_WINSOCK
log_err("sendto: %s", strerror(errno));
#else
log_err("sendto: %s", wsa_strerror(WSAGetLastError()));
#endif
} else if(sent != (ssize_t)sldns_buffer_limit(pkt)) {
log_err("sendto: partial send");
}
p->lastuse = *now;
p->numsent++;
}
}
/** do proxy for one readable client */
static void
do_proxy(struct proxy* p, int retsock, sldns_buffer* pkt)
{
int i;
ssize_t r;
for(i=0; i<TRIES_PER_SELECT; i++) {
r = recv(p->s, (void*)sldns_buffer_begin(pkt),
sldns_buffer_capacity(pkt), 0);
if(r == -1) {
#ifndef USE_WINSOCK
if(errno == EAGAIN || errno == EINTR)
return;
log_err("recv: %s", strerror(errno));
#else
if(WSAGetLastError() == WSAEINPROGRESS ||
WSAGetLastError() == WSAEWOULDBLOCK)
return;
log_err("recv: %s", wsa_strerror(WSAGetLastError()));
#endif
return;
}
sldns_buffer_set_limit(pkt, (size_t)r);
log_addr(1, "return reply to client", &p->addr, p->addr_len);
/* send reply back to the real client */
p->numreturn++;
r = sendto(retsock, (void*)sldns_buffer_begin(pkt), (size_t)r,
0, (struct sockaddr*)&p->addr, p->addr_len);
if(r == -1) {
#ifndef USE_WINSOCK
log_err("sendto: %s", strerror(errno));
#else
log_err("sendto: %s", wsa_strerror(WSAGetLastError()));
#endif
}
}
}
/** proxy return replies to clients */
static void
service_proxy(fd_set* rset, int retsock, struct proxy* proxies,
sldns_buffer* pkt, struct timeval* now)
{
struct proxy* p;
for(p = proxies; p; p = p->next) {
if(FD_ISSET(p->s, rset)) {
p->lastuse = *now;
do_proxy(p, retsock, pkt);
}
}
}
/** find or else create proxy for this remote client */
static struct proxy*
find_create_proxy(struct sockaddr_storage* from, socklen_t from_len,
fd_set* rorig, int* max, struct proxy** proxies, int serv_ip6,
struct timeval* now, struct timeval* reuse_timeout)
{
struct proxy* p;
struct timeval t;
for(p = *proxies; p; p = p->next) {
if(sockaddr_cmp(from, from_len, &p->addr, p->addr_len)==0)
return p;
}
/* possibly: reuse lapsed entries */
for(p = *proxies; p; p = p->next) {
if(p->numwait > p->numsent || p->numsent > p->numreturn)
continue;
t = *now;
dl_tv_subtract(&t, &p->lastuse);
if(dl_tv_smaller(&t, reuse_timeout))
continue;
/* yes! */
verbose(1, "reuse existing entry");
memmove(&p->addr, from, from_len);
p->addr_len = from_len;
p->numreuse++;
return p;
}
/* create new */
p = (struct proxy*)calloc(1, sizeof(*p));
if(!p) fatal_exit("out of memory");
p->s = socket(serv_ip6?AF_INET6:AF_INET, SOCK_DGRAM, 0);
if(p->s == -1) {
#ifndef USE_WINSOCK
fatal_exit("socket: %s", strerror(errno));
#else
fatal_exit("socket: %s", wsa_strerror(WSAGetLastError()));
#endif
}
fd_set_nonblock(p->s);
memmove(&p->addr, from, from_len);
p->addr_len = from_len;
p->next = *proxies;
*proxies = p;
FD_SET(FD_SET_T p->s, rorig);
if(p->s+1 > *max)
*max = p->s+1;
return p;
}
/** recv new waiting packets */
static void
service_recv(int s, struct ringbuf* ring, sldns_buffer* pkt,
fd_set* rorig, int* max, struct proxy** proxies,
struct sockaddr_storage* srv_addr, socklen_t srv_len,
struct timeval* now, struct timeval* delay, struct timeval* reuse)
{
int i;
struct sockaddr_storage from;
socklen_t from_len;
ssize_t len;
struct proxy* p;
for(i=0; i<TRIES_PER_SELECT; i++) {
from_len = (socklen_t)sizeof(from);
len = recvfrom(s, (void*)sldns_buffer_begin(pkt),
sldns_buffer_capacity(pkt), 0,
(struct sockaddr*)&from, &from_len);
if(len < 0) {
#ifndef USE_WINSOCK
if(errno == EAGAIN || errno == EINTR)
return;
fatal_exit("recvfrom: %s", strerror(errno));
#else
if(WSAGetLastError() == WSAEWOULDBLOCK ||
WSAGetLastError() == WSAEINPROGRESS)
return;
fatal_exit("recvfrom: %s",
wsa_strerror(WSAGetLastError()));
#endif
}
sldns_buffer_set_limit(pkt, (size_t)len);
/* find its proxy element */
p = find_create_proxy(&from, from_len, rorig, max, proxies,
addr_is_ip6(srv_addr, srv_len), now, reuse);
if(!p) fatal_exit("error: cannot find or create proxy");
p->lastuse = *now;
ring_add(ring, pkt, now, delay, p);
p->numwait++;
log_addr(1, "recv from client", &p->addr, p->addr_len);
}
}
/** delete tcp proxy */
static void
tcp_proxy_delete(struct tcp_proxy* p)
{
struct tcp_send_list* s, *sn;
if(!p)
return;
log_addr(1, "delete tcp proxy", &p->addr, p->addr_len);
s = p->querylist;
while(s) {
sn = s->next;
free(s->item);
free(s);
s = sn;
}
s = p->answerlist;
while(s) {
sn = s->next;
free(s->item);
free(s);
s = sn;
}
#ifndef USE_WINSOCK
close(p->client_s);
if(p->server_s != -1)
close(p->server_s);
#else
closesocket(p->client_s);
if(p->server_s != -1)
closesocket(p->server_s);
#endif
free(p);
}
/** accept new TCP connections, and set them up */
static void
service_tcp_listen(int s, fd_set* rorig, int* max, struct tcp_proxy** proxies,
struct sockaddr_storage* srv_addr, socklen_t srv_len,
struct timeval* now, struct timeval* tcp_timeout)
{
int newfd;
struct sockaddr_storage addr;
struct tcp_proxy* p;
socklen_t addr_len;
newfd = accept(s, (struct sockaddr*)&addr, &addr_len);
if(newfd == -1) {
#ifndef USE_WINSOCK
if(errno == EAGAIN || errno == EINTR)
return;
fatal_exit("accept: %s", strerror(errno));
#else
if(WSAGetLastError() == WSAEWOULDBLOCK ||
WSAGetLastError() == WSAEINPROGRESS ||
WSAGetLastError() == WSAECONNRESET)
return;
fatal_exit("accept: %s", wsa_strerror(WSAGetLastError()));
#endif
}
p = (struct tcp_proxy*)calloc(1, sizeof(*p));
if(!p) fatal_exit("out of memory");
memmove(&p->addr, &addr, addr_len);
p->addr_len = addr_len;
log_addr(1, "new tcp proxy", &p->addr, p->addr_len);
p->client_s = newfd;
p->server_s = socket(addr_is_ip6(srv_addr, srv_len)?AF_INET6:AF_INET,
SOCK_STREAM, 0);
if(p->server_s == -1) {
#ifndef USE_WINSOCK
fatal_exit("tcp socket: %s", strerror(errno));
#else
fatal_exit("tcp socket: %s", wsa_strerror(WSAGetLastError()));
#endif
}
fd_set_nonblock(p->client_s);
fd_set_nonblock(p->server_s);
if(connect(p->server_s, (struct sockaddr*)srv_addr, srv_len) == -1) {
#ifndef USE_WINSOCK
if(errno != EINPROGRESS) {
log_err("tcp connect: %s", strerror(errno));
close(p->server_s);
close(p->client_s);
#else
if(WSAGetLastError() != WSAEWOULDBLOCK &&
WSAGetLastError() != WSAEINPROGRESS) {
log_err("tcp connect: %s",
wsa_strerror(WSAGetLastError()));
closesocket(p->server_s);
closesocket(p->client_s);
#endif
free(p);
return;
}
}
p->timeout = *now;
dl_tv_add(&p->timeout, tcp_timeout);
/* listen to client and server */
FD_SET(FD_SET_T p->client_s, rorig);
FD_SET(FD_SET_T p->server_s, rorig);
if(p->client_s+1 > *max)
*max = p->client_s+1;
if(p->server_s+1 > *max)
*max = p->server_s+1;
/* add into proxy list */
p->next = *proxies;
*proxies = p;
}
/** relay TCP, read a part */
static int
tcp_relay_read(int s, struct tcp_send_list** first,
struct tcp_send_list** last, struct timeval* now,
struct timeval* delay, sldns_buffer* pkt)
{
struct tcp_send_list* item;
ssize_t r = recv(s, (void*)sldns_buffer_begin(pkt),
sldns_buffer_capacity(pkt), 0);
if(r == -1) {
#ifndef USE_WINSOCK
if(errno == EINTR || errno == EAGAIN)
return 1;
log_err("tcp read: %s", strerror(errno));
#else
if(WSAGetLastError() == WSAEINPROGRESS ||
WSAGetLastError() == WSAEWOULDBLOCK)
return 1;
log_err("tcp read: %s", wsa_strerror(WSAGetLastError()));
#endif
return 0;
} else if(r == 0) {
/* connection closed */
return 0;
}
item = (struct tcp_send_list*)malloc(sizeof(*item));
if(!item) {
log_err("out of memory");
return 0;
}
verbose(1, "read item len %d", (int)r);
item->len = (size_t)r;
item->item = memdup(sldns_buffer_begin(pkt), item->len);
if(!item->item) {
free(item);
log_err("out of memory");
return 0;
}
item->done = 0;
item->wait = *now;
dl_tv_add(&item->wait, delay);
item->next = NULL;
/* link in */
if(*first) {
(*last)->next = item;
} else {
*first = item;
}
*last = item;
return 1;
}
/** relay TCP, write a part */
static int
tcp_relay_write(int s, struct tcp_send_list** first,
struct tcp_send_list** last, struct timeval* now)
{
ssize_t r;
struct tcp_send_list* p;
while(*first) {
p = *first;
/* is the item ready? */
if(!dl_tv_smaller(&p->wait, now))
return 1;
/* write it */
r = send(s, (void*)(p->item + p->done), p->len - p->done, 0);
if(r == -1) {
#ifndef USE_WINSOCK
if(errno == EAGAIN || errno == EINTR)
return 1;
log_err("tcp write: %s", strerror(errno));
#else
if(WSAGetLastError() == WSAEWOULDBLOCK ||
WSAGetLastError() == WSAEINPROGRESS)
return 1;
log_err("tcp write: %s",
wsa_strerror(WSAGetLastError()));
#endif
return 0;
} else if(r == 0) {
/* closed */
return 0;
}
/* account it */
p->done += (size_t)r;
verbose(1, "write item %d of %d", (int)p->done, (int)p->len);
if(p->done >= p->len) {
free(p->item);
*first = p->next;
if(!*first)
*last = NULL;
free(p);
} else {
/* partial write */
return 1;
}
}
return 1;
}
/** perform TCP relaying */
static void
service_tcp_relay(struct tcp_proxy** tcp_proxies, struct timeval* now,
struct timeval* delay, struct timeval* tcp_timeout, sldns_buffer* pkt,
fd_set* rset, fd_set* rorig, fd_set* worig)
{
struct tcp_proxy* p, **prev;
struct timeval tout;
int delete_it;
p = *tcp_proxies;
prev = tcp_proxies;
tout = *now;
dl_tv_add(&tout, tcp_timeout);
while(p) {
delete_it = 0;
/* can we receive further queries? */
if(!delete_it && FD_ISSET(p->client_s, rset)) {
p->timeout = tout;
log_addr(1, "read tcp query", &p->addr, p->addr_len);
if(!tcp_relay_read(p->client_s, &p->querylist,
&p->querylast, now, delay, pkt))
delete_it = 1;
}
/* can we receive further answers? */
if(!delete_it && p->server_s != -1 &&
FD_ISSET(p->server_s, rset)) {
p->timeout = tout;
log_addr(1, "read tcp answer", &p->addr, p->addr_len);
if(!tcp_relay_read(p->server_s, &p->answerlist,
&p->answerlast, now, delay, pkt)) {
#ifndef USE_WINSOCK
close(p->server_s);
#else
closesocket(p->server_s);
#endif
FD_CLR(FD_SET_T p->server_s, worig);
FD_CLR(FD_SET_T p->server_s, rorig);
p->server_s = -1;
}
}
/* can we send on further queries */
if(!delete_it && p->querylist && p->server_s != -1) {
p->timeout = tout;
if(dl_tv_smaller(&p->querylist->wait, now))
log_addr(1, "write tcp query",
&p->addr, p->addr_len);
if(!tcp_relay_write(p->server_s, &p->querylist,
&p->querylast, now))
delete_it = 1;
if(p->querylist && p->server_s != -1 &&
dl_tv_smaller(&p->querylist->wait, now))
FD_SET(FD_SET_T p->server_s, worig);
else FD_CLR(FD_SET_T p->server_s, worig);
}
/* can we send on further answers */
if(!delete_it && p->answerlist) {
p->timeout = tout;
if(dl_tv_smaller(&p->answerlist->wait, now))
log_addr(1, "write tcp answer",
&p->addr, p->addr_len);
if(!tcp_relay_write(p->client_s, &p->answerlist,
&p->answerlast, now))
delete_it = 1;
if(p->answerlist && dl_tv_smaller(&p->answerlist->wait,
now))
FD_SET(FD_SET_T p->client_s, worig);
else FD_CLR(FD_SET_T p->client_s, worig);
if(!p->answerlist && p->server_s == -1)
delete_it = 1;
}
/* does this entry timeout? (unused too long) */
if(dl_tv_smaller(&p->timeout, now)) {
delete_it = 1;
}
if(delete_it) {
struct tcp_proxy* np = p->next;
*prev = np;
FD_CLR(FD_SET_T p->client_s, rorig);
FD_CLR(FD_SET_T p->client_s, worig);
if(p->server_s != -1) {
FD_CLR(FD_SET_T p->server_s, rorig);
FD_CLR(FD_SET_T p->server_s, worig);
}
tcp_proxy_delete(p);
p = np;
continue;
}
prev = &p->next;
p = p->next;
}
}
/** find waiting time */
static int
service_findwait(struct timeval* now, struct timeval* wait,
struct ringbuf* ring, struct tcp_proxy* tcplist)
{
/* first item is the time to wait */
struct timeval* peek = ring_peek_time(ring);
struct timeval tcv;
int have_tcpval = 0;
struct tcp_proxy* p;
/* also for TCP list the first in sendlists is the time to wait */
for(p=tcplist; p; p=p->next) {
if(!have_tcpval)
tcv = p->timeout;
have_tcpval = 1;
if(dl_tv_smaller(&p->timeout, &tcv))
tcv = p->timeout;
if(p->querylist && dl_tv_smaller(&p->querylist->wait, &tcv))
tcv = p->querylist->wait;
if(p->answerlist && dl_tv_smaller(&p->answerlist->wait, &tcv))
tcv = p->answerlist->wait;
}
if(peek) {
/* peek can be unaligned */
/* use wait as a temp variable */
memmove(wait, peek, sizeof(*wait));
if(!have_tcpval)
tcv = *wait;
else if(dl_tv_smaller(wait, &tcv))
tcv = *wait;
have_tcpval = 1;
}
if(have_tcpval) {
*wait = tcv;
dl_tv_subtract(wait, now);
return 1;
}
/* nothing, block */
return 0;
}
/** clear proxy list */
static void
proxy_list_clear(struct proxy* p)
{
char from[109];
struct proxy* np;
int i=0, port;
while(p) {
np = p->next;
port = (int)ntohs(((struct sockaddr_in*)&p->addr)->sin_port);
if(addr_is_ip6(&p->addr, p->addr_len)) {
if(inet_ntop(AF_INET6,
&((struct sockaddr_in6*)&p->addr)->sin6_addr,
from, (socklen_t)sizeof(from)) == 0)
(void)strlcpy(from, "err", sizeof(from));
} else {
if(inet_ntop(AF_INET,
&((struct sockaddr_in*)&p->addr)->sin_addr,
from, (socklen_t)sizeof(from)) == 0)
(void)strlcpy(from, "err", sizeof(from));
}
printf("client[%d]: last %s@%d of %d : %u in, %u out, "
"%u returned\n", i++, from, port, (int)p->numreuse+1,
(unsigned)p->numwait, (unsigned)p->numsent,
(unsigned)p->numreturn);
#ifndef USE_WINSOCK
close(p->s);
#else
closesocket(p->s);
#endif
free(p);
p = np;
}
}
/** clear TCP proxy list */
static void
tcp_proxy_list_clear(struct tcp_proxy* p)
{
struct tcp_proxy* np;
while(p) {
np = p->next;
tcp_proxy_delete(p);
p = np;
}
}
/** delayer service loop */
static void
service_loop(int udp_s, int listen_s, struct ringbuf* ring,
struct timeval* delay, struct timeval* reuse,
struct sockaddr_storage* srv_addr, socklen_t srv_len,
sldns_buffer* pkt)
{
fd_set rset, rorig;
fd_set wset, worig;
struct timeval now, wait;
int max, have_wait = 0;
struct proxy* proxies = NULL;
struct tcp_proxy* tcp_proxies = NULL;
struct timeval tcp_timeout;
tcp_timeout.tv_sec = 120;
tcp_timeout.tv_usec = 0;
#ifndef S_SPLINT_S
FD_ZERO(&rorig);
FD_ZERO(&worig);
FD_SET(FD_SET_T udp_s, &rorig);
FD_SET(FD_SET_T listen_s, &rorig);
#endif
max = udp_s + 1;
if(listen_s + 1 > max) max = listen_s + 1;
while(!do_quit) {
/* wait for events */
rset = rorig;
wset = worig;
if(have_wait)
verbose(1, "wait for %d.%6.6d",
(unsigned)wait.tv_sec, (unsigned)wait.tv_usec);
else verbose(1, "wait");
if(select(max, &rset, &wset, NULL, have_wait?&wait:NULL) < 0) {
if(errno == EAGAIN || errno == EINTR)
continue;
fatal_exit("select: %s", strerror(errno));
}
/* get current time */
if(gettimeofday(&now, NULL) < 0) {
if(errno == EAGAIN || errno == EINTR)
continue;
fatal_exit("gettimeofday: %s", strerror(errno));
}
verbose(1, "process at %u.%6.6u\n",
(unsigned)now.tv_sec, (unsigned)now.tv_usec);
/* sendout delayed queries to master server (frees up buffer)*/
service_send(ring, &now, pkt, srv_addr, srv_len);
/* proxy return replies */
service_proxy(&rset, udp_s, proxies, pkt, &now);
/* see what can be received to start waiting */
service_recv(udp_s, ring, pkt, &rorig, &max, &proxies,
srv_addr, srv_len, &now, delay, reuse);
/* see if there are new tcp connections */
service_tcp_listen(listen_s, &rorig, &max, &tcp_proxies,
srv_addr, srv_len, &now, &tcp_timeout);
/* service tcp connections */
service_tcp_relay(&tcp_proxies, &now, delay, &tcp_timeout,
pkt, &rset, &rorig, &worig);
/* see what next timeout is (if any) */
have_wait = service_findwait(&now, &wait, ring, tcp_proxies);
}
proxy_list_clear(proxies);
tcp_proxy_list_clear(tcp_proxies);
}
/** delayer main service routine */
static void
service(const char* bind_str, int bindport, const char* serv_str,
size_t memsize, int delay_msec)
{
struct sockaddr_storage bind_addr, srv_addr;
socklen_t bind_len, srv_len;
struct ringbuf* ring = ring_create(memsize);
struct timeval delay, reuse;
sldns_buffer* pkt;
int i, s, listen_s;
#ifndef S_SPLINT_S
delay.tv_sec = delay_msec / 1000;
delay.tv_usec = (delay_msec % 1000)*1000;
#endif
reuse = delay; /* reuse is max(4*delay, 1 second) */
dl_tv_add(&reuse, &delay);
dl_tv_add(&reuse, &delay);
dl_tv_add(&reuse, &delay);
if(reuse.tv_sec == 0)
reuse.tv_sec = 1;
if(!extstrtoaddr(serv_str, &srv_addr, &srv_len)) {
printf("cannot parse forward address: %s\n", serv_str);
exit(1);
}
pkt = sldns_buffer_new(65535);
if(!pkt)
fatal_exit("out of memory");
if( signal(SIGINT, delayer_sigh) == SIG_ERR ||
#ifdef SIGHUP
signal(SIGHUP, delayer_sigh) == SIG_ERR ||
#endif
#ifdef SIGQUIT
signal(SIGQUIT, delayer_sigh) == SIG_ERR ||
#endif
#ifdef SIGBREAK
signal(SIGBREAK, delayer_sigh) == SIG_ERR ||
#endif
#ifdef SIGALRM
signal(SIGALRM, delayer_sigh) == SIG_ERR ||
#endif
signal(SIGTERM, delayer_sigh) == SIG_ERR)
fatal_exit("could not bind to signal");
/* bind UDP port */
if((s = socket(str_is_ip6(bind_str)?AF_INET6:AF_INET,
SOCK_DGRAM, 0)) == -1) {
#ifndef USE_WINSOCK
fatal_exit("socket: %s", strerror(errno));
#else
fatal_exit("socket: %s", wsa_strerror(WSAGetLastError()));
#endif
}
i=0;
if(bindport == 0) {
bindport = 1024 + random()%64000;
i = 100;
}
while(1) {
if(!ipstrtoaddr(bind_str, bindport, &bind_addr, &bind_len)) {
printf("cannot parse listen address: %s\n", bind_str);
exit(1);
}
if(bind(s, (struct sockaddr*)&bind_addr, bind_len) == -1) {
#ifndef USE_WINSOCK
log_err("bind: %s", strerror(errno));
#else
log_err("bind: %s", wsa_strerror(WSAGetLastError()));
#endif
if(i--==0)
fatal_exit("cannot bind any port");
bindport = 1024 + random()%64000;
} else break;
}
fd_set_nonblock(s);
/* and TCP port */
if((listen_s = socket(str_is_ip6(bind_str)?AF_INET6:AF_INET,
SOCK_STREAM, 0)) == -1) {
#ifndef USE_WINSOCK
fatal_exit("tcp socket: %s", strerror(errno));
#else
fatal_exit("tcp socket: %s", wsa_strerror(WSAGetLastError()));
#endif
}
#ifdef SO_REUSEADDR
if(1) {
int on = 1;
if(setsockopt(listen_s, SOL_SOCKET, SO_REUSEADDR, (void*)&on,
(socklen_t)sizeof(on)) < 0)
#ifndef USE_WINSOCK
fatal_exit("setsockopt(.. SO_REUSEADDR ..) failed: %s",
strerror(errno));
#else
fatal_exit("setsockopt(.. SO_REUSEADDR ..) failed: %s",
wsa_strerror(WSAGetLastError()));
#endif
}
#endif
if(bind(listen_s, (struct sockaddr*)&bind_addr, bind_len) == -1) {
#ifndef USE_WINSOCK
fatal_exit("tcp bind: %s", strerror(errno));
#else
fatal_exit("tcp bind: %s", wsa_strerror(WSAGetLastError()));
#endif
}
if(listen(listen_s, 5) == -1) {
#ifndef USE_WINSOCK
fatal_exit("tcp listen: %s", strerror(errno));
#else
fatal_exit("tcp listen: %s", wsa_strerror(WSAGetLastError()));
#endif
}
fd_set_nonblock(listen_s);
printf("listening on port: %d\n", bindport);
/* process loop */
do_quit = 0;
service_loop(s, listen_s, ring, &delay, &reuse, &srv_addr, srv_len,
pkt);
/* cleanup */
verbose(1, "cleanup");
#ifndef USE_WINSOCK
close(s);
close(listen_s);
#else
closesocket(s);
closesocket(listen_s);
#endif
sldns_buffer_free(pkt);
ring_delete(ring);
}
/** getopt global, in case header files fail to declare it. */
extern int optind;
/** getopt global, in case header files fail to declare it. */
extern char* optarg;
/** main program for delayer */
int main(int argc, char** argv)
{
int c; /* defaults */
const char* server = "127.0.0.1@53";
const char* bindto = "0.0.0.0";
int bindport = 0;
size_t memsize = 10*1024*1024;
int delay = 100;
verbosity = 0;
log_init(0, 0, 0);
log_ident_set("delayer");
srandom(time(NULL) ^ getpid());
if(argc == 1) usage(argv);
while( (c=getopt(argc, argv, "b:d:f:hm:p:")) != -1) {
switch(c) {
case 'b':
bindto = optarg;
break;
case 'd':
if(atoi(optarg)==0 && strcmp(optarg,"0")!=0) {
printf("bad delay: %s\n", optarg);
return 1;
}
delay = atoi(optarg);
break;
case 'f':
server = optarg;
break;
case 'm':
if(!cfg_parse_memsize(optarg, &memsize)) {
printf("bad memsize: %s\n", optarg);
return 1;
}
break;
case 'p':
if(atoi(optarg)==0 && strcmp(optarg,"0")!=0) {
printf("bad port nr: %s\n", optarg);
return 1;
}
bindport = atoi(optarg);
break;
case 'h':
case '?':
default:
usage(argv);
}
}
argc -= optind;
argv += optind;
if(argc != 0)
usage(argv);
printf("bind to %s @ %d and forward to %s after %d msec\n",
bindto, bindport, server, delay);
service(bindto, bindport, server, memsize, delay);
return 0;
}
