/* * 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 #endif #ifdef HAVE_TIME_H #include #endif #include #include "util/net_help.h" #include "util/config_file.h" #include "ldns/sbuffer.h" #include /** 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; is, (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; ilastuse = *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; }