X-Git-Url: http://www.chiark.greenend.org.uk/ucgi/~ianmdlvl/git?a=blobdiff_plain;f=src%2Fevent.c;h=b36288ddfab610e305a4205d659f963bdaabb4d4;hb=17afb298d90c5aafed76bd3855a5fe7dcd58594c;hp=f1d22dc7d9a95b6853583e008d4184c7099c3c7d;hpb=239d2e4dfb6fcfc26fe3f740efae8f6944b99799;p=adns.git diff --git a/src/event.c b/src/event.c index f1d22dc..b36288d 100644 --- a/src/event.c +++ b/src/event.c @@ -5,16 +5,16 @@ * - user-visible check/wait and event-loop-related functions */ /* - * This file is - * Copyright (C) 1997-2000 Ian Jackson - * - * It is part of adns, which is - * Copyright (C) 1997-2000 Ian Jackson - * Copyright (C) 1999-2000 Tony Finch + * This file is part of adns, which is + * Copyright (C) 1997-2000,2003,2006,2014-2016 Ian Jackson + * Copyright (C) 2014 Mark Wooding + * Copyright (C) 1999-2000,2003,2006 Tony Finch + * Copyright (C) 1991 Massachusetts Institute of Technology + * (See the file INSTALL for full details.) * * This program is free software; you can redistribute it and/or modify * it under the terms of the GNU General Public License as published by - * the Free Software Foundation; either version 2, or (at your option) + * the Free Software Foundation; either version 3, or (at your option) * any later version. * * This program is distributed in the hope that it will be useful, @@ -23,8 +23,7 @@ * GNU General Public License for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software Foundation, - * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * along with this program; if not, write to the Free Software Foundation. */ #include @@ -44,9 +43,6 @@ /* TCP connection management. */ static void tcp_close(adns_state ads) { - int serv; - - serv= ads->tcpserver; close(ads->tcpsocket); ads->tcpsocket= -1; ads->tcprecv.used= ads->tcprecv_skip= ads->tcpsend.used= 0; @@ -83,9 +79,24 @@ static void tcp_connected(adns_state ads, struct timeval now) { } } +static void tcp_broken_events(adns_state ads) { + adns_query qu, nqu; + + assert(ads->tcpstate == server_broken); + for (qu= ads->tcpw.head; qu; qu= nqu) { + nqu= qu->next; + assert(qu->state == query_tcpw); + if (qu->retries > ads->nservers) { + LIST_UNLINK(ads->tcpw,qu); + adns__query_fail(qu,adns_s_allservfail); + } + } + ads->tcpstate= server_disconnected; +} + void adns__tcp_tryconnect(adns_state ads, struct timeval now) { int r, fd, tries; - struct sockaddr_in addr; + adns_rr_addr *addr; struct protoent *proto; for (tries=0; triesnservers; tries++) { @@ -105,23 +116,24 @@ void adns__tcp_tryconnect(adns_state ads, struct timeval now) { assert(!ads->tcprecv_skip); proto= getprotobyname("tcp"); - if (!proto) { adns__diag(ads,-1,0,"unable to find protocol no. for TCP !"); return; } - fd= socket(AF_INET,SOCK_STREAM,proto->p_proto); + if (!proto) { + adns__diag(ads,-1,0,"unable to find protocol no. for TCP !"); + return; + } + addr = &ads->servers[ads->tcpserver]; + fd= socket(addr->addr.sa.sa_family, SOCK_STREAM, proto->p_proto); if (fd<0) { adns__diag(ads,-1,0,"cannot create TCP socket: %s",strerror(errno)); return; } r= adns__setnonblock(ads,fd); if (r) { - adns__diag(ads,-1,0,"cannot make TCP socket nonblocking: %s",strerror(r)); + adns__diag(ads,-1,0,"cannot make TCP socket nonblocking:" + " %s",strerror(r)); close(fd); return; } - memset(&addr,0,sizeof(addr)); - addr.sin_family= AF_INET; - addr.sin_port= htons(DNS_PORT); - addr.sin_addr= ads->servers[ads->tcpserver].addr; - r= connect(fd,(const struct sockaddr*)&addr,sizeof(addr)); + r= connect(fd,&addr->addr.sa,addr->len); ads->tcpsocket= fd; ads->tcpstate= server_connecting; if (r==0) { tcp_connected(ads,now); return; } @@ -131,7 +143,7 @@ void adns__tcp_tryconnect(adns_state ads, struct timeval now) { return; } adns__tcp_broken(ads,"connect",strerror(errno)); - ads->tcpstate= server_disconnected; + tcp_broken_events(ads); } } @@ -218,21 +230,11 @@ static void timeouts_queue(adns_state ads, int act, static void tcp_events(adns_state ads, int act, struct timeval **tv_io, struct timeval *tvbuf, struct timeval now) { - adns_query qu, nqu; - for (;;) { switch (ads->tcpstate) { case server_broken: if (!act) { inter_immed(tv_io,tvbuf); return; } - for (qu= ads->tcpw.head; qu; qu= nqu) { - nqu= qu->next; - assert(qu->state == query_tcpw); - if (qu->retries > ads->nservers) { - LIST_UNLINK(ads->tcpw,qu); - adns__query_fail(qu,adns_s_allservfail); - } - } - ads->tcpstate= server_disconnected; + tcp_broken_events(ads); case server_disconnected: /* fall through */ if (!ads->tcpw.head) return; if (!act) { inter_immed(tv_io,tvbuf); return; } @@ -284,7 +286,7 @@ void adns_firsttimeout(adns_state ads, struct timeval now) { adns__consistency(ads,0,cc_entex); adns__timeouts(ads, 0, tv_io,tvbuf, now); - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } void adns_processtimeouts(adns_state ads, const struct timeval *now) { @@ -293,7 +295,7 @@ void adns_processtimeouts(adns_state ads, const struct timeval *now) { adns__consistency(ads,0,cc_entex); adns__must_gettimeofday(ads,&now,&tv_buf); if (now) adns__timeouts(ads, 1, 0,0, *now); - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } /* fd handling functions. These are the top-level of the real work of @@ -302,34 +304,47 @@ void adns_processtimeouts(adns_state ads, const struct timeval *now) { int adns__pollfds(adns_state ads, struct pollfd pollfds_buf[MAX_POLLFDS]) { /* Returns the number of entries filled in. Always zeroes revents. */ + int nwanted=0; +#define ADD_POLLFD(wantfd, wantevents) do{ \ + pollfds_buf[nwanted].fd= (wantfd); \ + pollfds_buf[nwanted].events= (wantevents); \ + pollfds_buf[nwanted].revents= 0; \ + nwanted++; \ + }while(0) - assert(MAX_POLLFDS==2); + int i; - pollfds_buf[0].fd= ads->udpsocket; - pollfds_buf[0].events= POLLIN; - pollfds_buf[0].revents= 0; + assert(MAX_POLLFDS == MAXUDP + 1); + + for (i=0; inudpsockets; i++) + ADD_POLLFD(ads->udpsockets[i].fd, POLLIN); switch (ads->tcpstate) { case server_disconnected: case server_broken: - return 1; + break; case server_connecting: - pollfds_buf[1].events= POLLOUT; + ADD_POLLFD(ads->tcpsocket, POLLOUT); break; case server_ok: - pollfds_buf[1].events= ads->tcpsend.used ? POLLIN|POLLOUT|POLLPRI : POLLIN|POLLPRI; + ADD_POLLFD(ads->tcpsocket, + ads->tcpsend.used ? POLLIN|POLLOUT|POLLPRI : POLLIN|POLLPRI); break; default: abort(); } - pollfds_buf[1].fd= ads->tcpsocket; - return 2; + assert(nwanted<=MAX_POLLFDS); +#undef ADD_POLLFD + return nwanted; } int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { - int want, dgramlen, r, udpaddrlen, serv, old_skip; + int want, dgramlen, r, i, serv, old_skip; + socklen_t udpaddrlen; byte udpbuf[DNS_MAXUDP]; - struct sockaddr_in udpaddr; + char addrbuf[ADNS_ADDR2TEXT_BUFLEN]; + struct udpsocket *udp; + adns_sockaddr udpaddr; adns__consistency(ads,0,cc_entex); @@ -358,7 +373,8 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { want= 2; } ads->tcprecv.used -= ads->tcprecv_skip; - memmove(ads->tcprecv.buf,ads->tcprecv.buf+ads->tcprecv_skip,ads->tcprecv.used); + memmove(ads->tcprecv.buf, ads->tcprecv.buf+ads->tcprecv_skip, + ads->tcprecv.used); ads->tcprecv_skip= 0; if (!adns__vbuf_ensure(&ads->tcprecv,want)) { r= ENOMEM; goto xit; } assert(ads->tcprecv.used <= ads->tcprecv.avail); @@ -381,11 +397,12 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { default: abort(); } - if (fd == ads->udpsocket) { + for (i=0; inudpsockets; i++) { + udp= &ads->udpsockets[i]; + if (fd != udp->fd) continue; for (;;) { udpaddrlen= sizeof(udpaddr); - r= recvfrom(ads->udpsocket,udpbuf,sizeof(udpbuf),0, - (struct sockaddr*)&udpaddr,&udpaddrlen); + r= recvfrom(fd,udpbuf,sizeof(udpbuf),0, &udpaddr.sa,&udpaddrlen); if (r<0) { if (errno == EAGAIN || errno == EWOULDBLOCK) { r= 0; goto xit; } if (errno == EINTR) continue; @@ -393,37 +410,23 @@ int adns_processreadable(adns_state ads, int fd, const struct timeval *now) { adns__warn(ads,-1,0,"datagram receive error: %s",strerror(errno)); r= 0; goto xit; } - if (udpaddrlen != sizeof(udpaddr)) { - adns__diag(ads,-1,0,"datagram received with wrong address length %d" - " (expected %lu)", udpaddrlen, - (unsigned long)sizeof(udpaddr)); - continue; - } - if (udpaddr.sin_family != AF_INET) { - adns__diag(ads,-1,0,"datagram received with wrong protocol family" - " %u (expected %u)",udpaddr.sin_family,AF_INET); - continue; - } - if (ntohs(udpaddr.sin_port) != DNS_PORT) { - adns__diag(ads,-1,0,"datagram received from wrong port %u (expected %u)", - ntohs(udpaddr.sin_port),DNS_PORT); - continue; - } for (serv= 0; serv < ads->nservers && - ads->servers[serv].addr.s_addr != udpaddr.sin_addr.s_addr; + !adns__sockaddrs_equal(&udpaddr.sa, + &ads->servers[serv].addr.sa); serv++); if (serv >= ads->nservers) { adns__warn(ads,-1,0,"datagram received from unknown nameserver %s", - inet_ntoa(udpaddr.sin_addr)); + adns__sockaddr_ntoa(&udpaddr.sa, addrbuf)); continue; } adns__procdgram(ads,udpbuf,r,serv,0,*now); } + break; } r= 0; xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; } @@ -441,8 +444,24 @@ int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { assert(ads->tcprecv.used==0); assert(ads->tcprecv_skip==0); for (;;) { + /* This function can be called even if the fd wasn't actually + * flagged as writeable. For asynch tcp connect we have to + * actually use the writeability to tell us the connect has + * completed (or failed), so we need to double check. */ + fd_set writeable; + struct timeval timeout = { 0,0 }; + FD_ZERO(&writeable); + FD_SET(ads->tcpsocket,&writeable); + r= select(ads->tcpsocket+1,0,&writeable,0,&timeout); + if (r==0) break; + if (r<0) { + if (errno==EINTR) continue; + adns__tcp_broken(ads,"select","failed connecting writeability check"); + r= 0; goto xit; + } + assert(FD_ISSET(ads->tcpsocket,&writeable)); if (!adns__vbuf_ensure(&ads->tcprecv,1)) { r= ENOMEM; goto xit; } - r= read(ads->tcpsocket,&ads->tcprecv.buf,1); + r= read(ads->tcpsocket,ads->tcprecv.buf,1); if (r==0 || (r<0 && (errno==EAGAIN || errno==EWOULDBLOCK))) { tcp_connected(ads,*now); r= 0; goto xit; @@ -480,11 +499,12 @@ int adns_processwriteable(adns_state ads, int fd, const struct timeval *now) { } r= 0; xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; } -int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { +int adns_processexceptional(adns_state ads, int fd, + const struct timeval *now) { adns__consistency(ads,0,cc_entex); switch (ads->tcpstate) { case server_disconnected: @@ -498,14 +518,15 @@ int adns_processexceptional(adns_state ads, int fd, const struct timeval *now) { default: abort(); } - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return 0; } static void fd_event(adns_state ads, int fd, int revent, int pollflag, int maxfd, const fd_set *fds, - int (*func)(adns_state, int fd, const struct timeval *now), + int (*func)(adns_state, int fd, + const struct timeval *now), struct timeval now, int *r_r) { int r; @@ -516,7 +537,8 @@ static void fd_event(adns_state ads, int fd, if (r_r) { *r_r= r; } else { - adns__diag(ads,-1,0,"process fd failed after select: %s",strerror(errno)); + adns__diag(ads,-1,0,"process fd failed after select:" + " %s",strerror(errno)); adns_globalsystemfailure(ads); } } @@ -533,9 +555,12 @@ void adns__fdevents(adns_state ads, fd= pollfds[i].fd; if (fd >= maxfd) maxfd= fd+1; revents= pollfds[i].revents; - fd_event(ads,fd, revents,POLLIN, maxfd,readfds, adns_processreadable,now,r_r); - fd_event(ads,fd, revents,POLLOUT, maxfd,writefds, adns_processwriteable,now,r_r); - fd_event(ads,fd, revents,POLLPRI, maxfd,exceptfds, adns_processexceptional,now,r_r); +#define EV(pollfl,fds,how) \ + fd_event(ads,fd, revents,pollfl, maxfd,fds, adns_process##how,now,r_r) + EV( POLLIN, readfds, readable ); + EV( POLLOUT, writefds, writeable ); + EV( POLLPRI, exceptfds, exceptional ); +#undef EV } } @@ -570,7 +595,7 @@ void adns_beforeselect(adns_state ads, int *maxfd_io, fd_set *readfds_io, *maxfd_io= maxfd; xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, @@ -592,7 +617,7 @@ void adns_afterselect(adns_state ads, int maxfd, const fd_set *readfds, maxfd,readfds,writefds,exceptfds, *now, 0); xit: - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } /* General helpful functions. */ @@ -614,7 +639,7 @@ void adns_globalsystemfailure(adns_state ads) { default: abort(); } - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); } int adns_processany(adns_state ads) { @@ -639,7 +664,7 @@ int adns_processany(adns_state ads) { 0,0,0,0, now,&r); - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return 0; } @@ -703,7 +728,7 @@ int adns_wait(adns_state ads, adns_afterselect(ads,maxfd,&readfds,&writefds,&exceptfds,0); } } - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; } @@ -719,6 +744,6 @@ int adns_check(adns_state ads, if (!r) adns__autosys(ads,now); r= adns__internal_check(ads,query_io,answer_r,context_r); - adns__consistency(ads,0,cc_entex); + adns__returning(ads,0); return r; }