/* * util/netevent.c - event notification * * 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 contains event notification functions. */ #include "config.h" #include "util/netevent.h" #include "util/ub_event.h" #include "util/log.h" #include "util/net_help.h" #include "util/tcp_conn_limit.h" #include "util/fptr_wlist.h" #include "sldns/pkthdr.h" #include "sldns/sbuffer.h" #include "sldns/str2wire.h" #include "dnstap/dnstap.h" #include "dnscrypt/dnscrypt.h" #include "services/listen_dnsport.h" #ifdef HAVE_SYS_TYPES_H #include #endif #ifdef HAVE_SYS_SOCKET_H #include #endif #ifdef HAVE_NETDB_H #include #endif #ifdef HAVE_OPENSSL_SSL_H #include #endif #ifdef HAVE_OPENSSL_ERR_H #include #endif /* -------- Start of local definitions -------- */ /** if CMSG_ALIGN is not defined on this platform, a workaround */ #ifndef CMSG_ALIGN # ifdef __CMSG_ALIGN # define CMSG_ALIGN(n) __CMSG_ALIGN(n) # elif defined(CMSG_DATA_ALIGN) # define CMSG_ALIGN _CMSG_DATA_ALIGN # else # define CMSG_ALIGN(len) (((len)+sizeof(long)-1) & ~(sizeof(long)-1)) # endif #endif /** if CMSG_LEN is not defined on this platform, a workaround */ #ifndef CMSG_LEN # define CMSG_LEN(len) (CMSG_ALIGN(sizeof(struct cmsghdr))+(len)) #endif /** if CMSG_SPACE is not defined on this platform, a workaround */ #ifndef CMSG_SPACE # ifdef _CMSG_HDR_ALIGN # define CMSG_SPACE(l) (CMSG_ALIGN(l)+_CMSG_HDR_ALIGN(sizeof(struct cmsghdr))) # else # define CMSG_SPACE(l) (CMSG_ALIGN(l)+CMSG_ALIGN(sizeof(struct cmsghdr))) # endif #endif /** The TCP writing query timeout in milliseconds */ #define TCP_QUERY_TIMEOUT 120000 /** The minimum actual TCP timeout to use, regardless of what we advertise, * in msec */ #define TCP_QUERY_TIMEOUT_MINIMUM 200 #ifndef NONBLOCKING_IS_BROKEN /** number of UDP reads to perform per read indication from select */ #define NUM_UDP_PER_SELECT 100 #else #define NUM_UDP_PER_SELECT 1 #endif /** * The internal event structure for keeping ub_event info for the event. * Possibly other structures (list, tree) this is part of. */ struct internal_event { /** the comm base */ struct comm_base* base; /** ub_event event type */ struct ub_event* ev; }; /** * Internal base structure, so that every thread has its own events. */ struct internal_base { /** ub_event event_base type. */ struct ub_event_base* base; /** seconds time pointer points here */ time_t secs; /** timeval with current time */ struct timeval now; /** the event used for slow_accept timeouts */ struct ub_event* slow_accept; /** true if slow_accept is enabled */ int slow_accept_enabled; }; /** * Internal timer structure, to store timer event in. */ struct internal_timer { /** the super struct from which derived */ struct comm_timer super; /** the comm base */ struct comm_base* base; /** ub_event event type */ struct ub_event* ev; /** is timer enabled */ uint8_t enabled; }; /** * Internal signal structure, to store signal event in. */ struct internal_signal { /** ub_event event type */ struct ub_event* ev; /** next in signal list */ struct internal_signal* next; }; /** create a tcp handler with a parent */ static struct comm_point* comm_point_create_tcp_handler( struct comm_base *base, struct comm_point* parent, size_t bufsize, struct sldns_buffer* spoolbuf, comm_point_callback_type* callback, void* callback_arg, struct unbound_socket* socket); /* -------- End of local definitions -------- */ struct comm_base* comm_base_create(int sigs) { struct comm_base* b = (struct comm_base*)calloc(1, sizeof(struct comm_base)); const char *evnm="event", *evsys="", *evmethod=""; if(!b) return NULL; b->eb = (struct internal_base*)calloc(1, sizeof(struct internal_base)); if(!b->eb) { free(b); return NULL; } b->eb->base = ub_default_event_base(sigs, &b->eb->secs, &b->eb->now); if(!b->eb->base) { free(b->eb); free(b); return NULL; } ub_comm_base_now(b); ub_get_event_sys(b->eb->base, &evnm, &evsys, &evmethod); verbose(VERB_ALGO, "%s %s uses %s method.", evnm, evsys, evmethod); return b; } struct comm_base* comm_base_create_event(struct ub_event_base* base) { struct comm_base* b = (struct comm_base*)calloc(1, sizeof(struct comm_base)); if(!b) return NULL; b->eb = (struct internal_base*)calloc(1, sizeof(struct internal_base)); if(!b->eb) { free(b); return NULL; } b->eb->base = base; ub_comm_base_now(b); return b; } void comm_base_delete(struct comm_base* b) { if(!b) return; if(b->eb->slow_accept_enabled) { if(ub_event_del(b->eb->slow_accept) != 0) { log_err("could not event_del slow_accept"); } ub_event_free(b->eb->slow_accept); } ub_event_base_free(b->eb->base); b->eb->base = NULL; free(b->eb); free(b); } void comm_base_delete_no_base(struct comm_base* b) { if(!b) return; if(b->eb->slow_accept_enabled) { if(ub_event_del(b->eb->slow_accept) != 0) { log_err("could not event_del slow_accept"); } ub_event_free(b->eb->slow_accept); } b->eb->base = NULL; free(b->eb); free(b); } void comm_base_timept(struct comm_base* b, time_t** tt, struct timeval** tv) { *tt = &b->eb->secs; *tv = &b->eb->now; } void comm_base_dispatch(struct comm_base* b) { int retval; retval = ub_event_base_dispatch(b->eb->base); if(retval < 0) { fatal_exit("event_dispatch returned error %d, " "errno is %s", retval, strerror(errno)); } } void comm_base_exit(struct comm_base* b) { if(ub_event_base_loopexit(b->eb->base) != 0) { log_err("Could not loopexit"); } } void comm_base_set_slow_accept_handlers(struct comm_base* b, void (*stop_acc)(void*), void (*start_acc)(void*), void* arg) { b->stop_accept = stop_acc; b->start_accept = start_acc; b->cb_arg = arg; } struct ub_event_base* comm_base_internal(struct comm_base* b) { return b->eb->base; } /** see if errno for udp has to be logged or not uses globals */ static int udp_send_errno_needs_log(struct sockaddr* addr, socklen_t addrlen) { /* do not log transient errors (unless high verbosity) */ #if defined(ENETUNREACH) || defined(EHOSTDOWN) || defined(EHOSTUNREACH) || defined(ENETDOWN) switch(errno) { # ifdef ENETUNREACH case ENETUNREACH: # endif # ifdef EHOSTDOWN case EHOSTDOWN: # endif # ifdef EHOSTUNREACH case EHOSTUNREACH: # endif # ifdef ENETDOWN case ENETDOWN: # endif case EPERM: case EACCES: if(verbosity < VERB_ALGO) return 0; default: break; } #endif /* permission denied is gotten for every send if the * network is disconnected (on some OS), squelch it */ if( ((errno == EPERM) # ifdef EADDRNOTAVAIL /* 'Cannot assign requested address' also when disconnected */ || (errno == EADDRNOTAVAIL) # endif ) && verbosity < VERB_ALGO) return 0; # ifdef EADDRINUSE /* If SO_REUSEADDR is set, we could try to connect to the same server * from the same source port twice. */ if(errno == EADDRINUSE && verbosity < VERB_DETAIL) return 0; # endif /* squelch errors where people deploy AAAA ::ffff:bla for * authority servers, which we try for intranets. */ if(errno == EINVAL && addr_is_ip4mapped( (struct sockaddr_storage*)addr, addrlen) && verbosity < VERB_DETAIL) return 0; /* SO_BROADCAST sockopt can give access to 255.255.255.255, * but a dns cache does not need it. */ if(errno == EACCES && addr_is_broadcast( (struct sockaddr_storage*)addr, addrlen) && verbosity < VERB_DETAIL) return 0; return 1; } int tcp_connect_errno_needs_log(struct sockaddr* addr, socklen_t addrlen) { return udp_send_errno_needs_log(addr, addrlen); } /* send a UDP reply */ int comm_point_send_udp_msg(struct comm_point *c, sldns_buffer* packet, struct sockaddr* addr, socklen_t addrlen, int is_connected) { ssize_t sent; log_assert(c->fd != -1); #ifdef UNBOUND_DEBUG if(sldns_buffer_remaining(packet) == 0) log_err("error: send empty UDP packet"); #endif log_assert(addr && addrlen > 0); if(!is_connected) { sent = sendto(c->fd, (void*)sldns_buffer_begin(packet), sldns_buffer_remaining(packet), 0, addr, addrlen); } else { sent = send(c->fd, (void*)sldns_buffer_begin(packet), sldns_buffer_remaining(packet), 0); } if(sent == -1) { /* try again and block, waiting for IO to complete, * we want to send the answer, and we will wait for * the ethernet interface buffer to have space. */ #ifndef USE_WINSOCK if(errno == EAGAIN || # ifdef EWOULDBLOCK errno == EWOULDBLOCK || # endif errno == ENOBUFS) { #else if(WSAGetLastError() == WSAEINPROGRESS || WSAGetLastError() == WSAENOBUFS || WSAGetLastError() == WSAEWOULDBLOCK) { #endif int e; fd_set_block(c->fd); if (!is_connected) { sent = sendto(c->fd, (void*)sldns_buffer_begin(packet), sldns_buffer_remaining(packet), 0, addr, addrlen); } else { sent = send(c->fd, (void*)sldns_buffer_begin(packet), sldns_buffer_remaining(packet), 0); } e = errno; fd_set_nonblock(c->fd); errno = e; } } if(sent == -1) { if(!udp_send_errno_needs_log(addr, addrlen)) return 0; if (!is_connected) { verbose(VERB_OPS, "sendto failed: %s", sock_strerror(errno)); } else { verbose(VERB_OPS, "send failed: %s", sock_strerror(errno)); } if(addr) log_addr(VERB_OPS, "remote address is", (struct sockaddr_storage*)addr, addrlen); return 0; } else if((size_t)sent != sldns_buffer_remaining(packet)) { log_err("sent %d in place of %d bytes", (int)sent, (int)sldns_buffer_remaining(packet)); return 0; } return 1; } #if defined(AF_INET6) && defined(IPV6_PKTINFO) && (defined(HAVE_RECVMSG) || defined(HAVE_SENDMSG)) /** print debug ancillary info */ static void p_ancil(const char* str, struct comm_reply* r) { if(r->srctype != 4 && r->srctype != 6) { log_info("%s: unknown srctype %d", str, r->srctype); return; } if(r->srctype == 6) { #ifdef IPV6_PKTINFO char buf[1024]; if(inet_ntop(AF_INET6, &r->pktinfo.v6info.ipi6_addr, buf, (socklen_t)sizeof(buf)) == 0) { (void)strlcpy(buf, "(inet_ntop error)", sizeof(buf)); } buf[sizeof(buf)-1]=0; log_info("%s: %s %d", str, buf, r->pktinfo.v6info.ipi6_ifindex); #endif } else if(r->srctype == 4) { #ifdef IP_PKTINFO char buf1[1024], buf2[1024]; if(inet_ntop(AF_INET, &r->pktinfo.v4info.ipi_addr, buf1, (socklen_t)sizeof(buf1)) == 0) { (void)strlcpy(buf1, "(inet_ntop error)", sizeof(buf1)); } buf1[sizeof(buf1)-1]=0; #ifdef HAVE_STRUCT_IN_PKTINFO_IPI_SPEC_DST if(inet_ntop(AF_INET, &r->pktinfo.v4info.ipi_spec_dst, buf2, (socklen_t)sizeof(buf2)) == 0) { (void)strlcpy(buf2, "(inet_ntop error)", sizeof(buf2)); } buf2[sizeof(buf2)-1]=0; #else buf2[0]=0; #endif log_info("%s: %d %s %s", str, r->pktinfo.v4info.ipi_ifindex, buf1, buf2); #elif defined(IP_RECVDSTADDR) char buf1[1024]; if(inet_ntop(AF_INET, &r->pktinfo.v4addr, buf1, (socklen_t)sizeof(buf1)) == 0) { (void)strlcpy(buf1, "(inet_ntop error)", sizeof(buf1)); } buf1[sizeof(buf1)-1]=0; log_info("%s: %s", str, buf1); #endif /* IP_PKTINFO or PI_RECVDSTDADDR */ } } #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_RECVMSG||HAVE_SENDMSG */ /** send a UDP reply over specified interface*/ static int comm_point_send_udp_msg_if(struct comm_point *c, sldns_buffer* packet, struct sockaddr* addr, socklen_t addrlen, struct comm_reply* r) { #if defined(AF_INET6) && defined(IPV6_PKTINFO) && defined(HAVE_SENDMSG) ssize_t sent; struct msghdr msg; struct iovec iov[1]; union { struct cmsghdr hdr; char buf[256]; } control; #ifndef S_SPLINT_S struct cmsghdr *cmsg; #endif /* S_SPLINT_S */ log_assert(c->fd != -1); #ifdef UNBOUND_DEBUG if(sldns_buffer_remaining(packet) == 0) log_err("error: send empty UDP packet"); #endif log_assert(addr && addrlen > 0); msg.msg_name = addr; msg.msg_namelen = addrlen; iov[0].iov_base = sldns_buffer_begin(packet); iov[0].iov_len = sldns_buffer_remaining(packet); msg.msg_iov = iov; msg.msg_iovlen = 1; msg.msg_control = control.buf; #ifndef S_SPLINT_S msg.msg_controllen = sizeof(control.buf); #endif /* S_SPLINT_S */ msg.msg_flags = 0; #ifndef S_SPLINT_S cmsg = CMSG_FIRSTHDR(&msg); if(r->srctype == 4) { #ifdef IP_PKTINFO void* cmsg_data; msg.msg_controllen = CMSG_SPACE(sizeof(struct in_pktinfo)); log_assert(msg.msg_controllen <= sizeof(control.buf)); cmsg->cmsg_level = IPPROTO_IP; cmsg->cmsg_type = IP_PKTINFO; memmove(CMSG_DATA(cmsg), &r->pktinfo.v4info, sizeof(struct in_pktinfo)); /* unset the ifindex to not bypass the routing tables */ cmsg_data = CMSG_DATA(cmsg); ((struct in_pktinfo *) cmsg_data)->ipi_ifindex = 0; cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_pktinfo)); #elif defined(IP_SENDSRCADDR) msg.msg_controllen = CMSG_SPACE(sizeof(struct in_addr)); log_assert(msg.msg_controllen <= sizeof(control.buf)); cmsg->cmsg_level = IPPROTO_IP; cmsg->cmsg_type = IP_SENDSRCADDR; memmove(CMSG_DATA(cmsg), &r->pktinfo.v4addr, sizeof(struct in_addr)); cmsg->cmsg_len = CMSG_LEN(sizeof(struct in_addr)); #else verbose(VERB_ALGO, "no IP_PKTINFO or IP_SENDSRCADDR"); msg.msg_control = NULL; #endif /* IP_PKTINFO or IP_SENDSRCADDR */ } else if(r->srctype == 6) { void* cmsg_data; msg.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo)); log_assert(msg.msg_controllen <= sizeof(control.buf)); cmsg->cmsg_level = IPPROTO_IPV6; cmsg->cmsg_type = IPV6_PKTINFO; memmove(CMSG_DATA(cmsg), &r->pktinfo.v6info, sizeof(struct in6_pktinfo)); /* unset the ifindex to not bypass the routing tables */ cmsg_data = CMSG_DATA(cmsg); ((struct in6_pktinfo *) cmsg_data)->ipi6_ifindex = 0; cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); } else { /* try to pass all 0 to use default route */ msg.msg_controllen = CMSG_SPACE(sizeof(struct in6_pktinfo)); log_assert(msg.msg_controllen <= sizeof(control.buf)); cmsg->cmsg_level = IPPROTO_IPV6; cmsg->cmsg_type = IPV6_PKTINFO; memset(CMSG_DATA(cmsg), 0, sizeof(struct in6_pktinfo)); cmsg->cmsg_len = CMSG_LEN(sizeof(struct in6_pktinfo)); } #endif /* S_SPLINT_S */ if(verbosity >= VERB_ALGO) p_ancil("send_udp over interface", r); sent = sendmsg(c->fd, &msg, 0); if(sent == -1) { /* try again and block, waiting for IO to complete, * we want to send the answer, and we will wait for * the ethernet interface buffer to have space. */ #ifndef USE_WINSOCK if(errno == EAGAIN || # ifdef EWOULDBLOCK errno == EWOULDBLOCK || # endif errno == ENOBUFS) { #else if(WSAGetLastError() == WSAEINPROGRESS || WSAGetLastError() == WSAENOBUFS || WSAGetLastError() == WSAEWOULDBLOCK) { #endif int e; fd_set_block(c->fd); sent = sendmsg(c->fd, &msg, 0); e = errno; fd_set_nonblock(c->fd); errno = e; } } if(sent == -1) { if(!udp_send_errno_needs_log(addr, addrlen)) return 0; verbose(VERB_OPS, "sendmsg failed: %s", strerror(errno)); log_addr(VERB_OPS, "remote address is", (struct sockaddr_storage*)addr, addrlen); #ifdef __NetBSD__ /* netbsd 7 has IP_PKTINFO for recv but not send */ if(errno == EINVAL && r->srctype == 4) log_err("sendmsg: No support for sendmsg(IP_PKTINFO). " "Please disable interface-automatic"); #endif return 0; } else if((size_t)sent != sldns_buffer_remaining(packet)) { log_err("sent %d in place of %d bytes", (int)sent, (int)sldns_buffer_remaining(packet)); return 0; } return 1; #else (void)c; (void)packet; (void)addr; (void)addrlen; (void)r; log_err("sendmsg: IPV6_PKTINFO not supported"); return 0; #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_SENDMSG */ } /** return true is UDP receive error needs to be logged */ static int udp_recv_needs_log(int err) { switch(err) { case EACCES: /* some hosts send ICMP 'Permission Denied' */ #ifndef USE_WINSOCK case ECONNREFUSED: # ifdef ENETUNREACH case ENETUNREACH: # endif # ifdef EHOSTDOWN case EHOSTDOWN: # endif # ifdef EHOSTUNREACH case EHOSTUNREACH: # endif # ifdef ENETDOWN case ENETDOWN: # endif #else /* USE_WINSOCK */ case WSAECONNREFUSED: case WSAENETUNREACH: case WSAEHOSTDOWN: case WSAEHOSTUNREACH: case WSAENETDOWN: #endif if(verbosity >= VERB_ALGO) return 1; return 0; default: break; } return 1; } void comm_point_udp_ancil_callback(int fd, short event, void* arg) { #if defined(AF_INET6) && defined(IPV6_PKTINFO) && defined(HAVE_RECVMSG) struct comm_reply rep; struct msghdr msg; struct iovec iov[1]; ssize_t rcv; union { struct cmsghdr hdr; char buf[256]; } ancil; int i; #ifndef S_SPLINT_S struct cmsghdr* cmsg; #endif /* S_SPLINT_S */ rep.c = (struct comm_point*)arg; log_assert(rep.c->type == comm_udp); if(!(event&UB_EV_READ)) return; log_assert(rep.c && rep.c->buffer && rep.c->fd == fd); ub_comm_base_now(rep.c->ev->base); for(i=0; ibuffer); rep.addrlen = (socklen_t)sizeof(rep.addr); log_assert(fd != -1); log_assert(sldns_buffer_remaining(rep.c->buffer) > 0); msg.msg_name = &rep.addr; msg.msg_namelen = (socklen_t)sizeof(rep.addr); iov[0].iov_base = sldns_buffer_begin(rep.c->buffer); iov[0].iov_len = sldns_buffer_remaining(rep.c->buffer); msg.msg_iov = iov; msg.msg_iovlen = 1; msg.msg_control = ancil.buf; #ifndef S_SPLINT_S msg.msg_controllen = sizeof(ancil.buf); #endif /* S_SPLINT_S */ msg.msg_flags = 0; rcv = recvmsg(fd, &msg, 0); if(rcv == -1) { if(errno != EAGAIN && errno != EINTR && udp_recv_needs_log(errno)) { log_err("recvmsg failed: %s", strerror(errno)); } return; } rep.addrlen = msg.msg_namelen; sldns_buffer_skip(rep.c->buffer, rcv); sldns_buffer_flip(rep.c->buffer); rep.srctype = 0; #ifndef S_SPLINT_S for(cmsg = CMSG_FIRSTHDR(&msg); cmsg != NULL; cmsg = CMSG_NXTHDR(&msg, cmsg)) { if( cmsg->cmsg_level == IPPROTO_IPV6 && cmsg->cmsg_type == IPV6_PKTINFO) { rep.srctype = 6; memmove(&rep.pktinfo.v6info, CMSG_DATA(cmsg), sizeof(struct in6_pktinfo)); break; #ifdef IP_PKTINFO } else if( cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_PKTINFO) { rep.srctype = 4; memmove(&rep.pktinfo.v4info, CMSG_DATA(cmsg), sizeof(struct in_pktinfo)); break; #elif defined(IP_RECVDSTADDR) } else if( cmsg->cmsg_level == IPPROTO_IP && cmsg->cmsg_type == IP_RECVDSTADDR) { rep.srctype = 4; memmove(&rep.pktinfo.v4addr, CMSG_DATA(cmsg), sizeof(struct in_addr)); break; #endif /* IP_PKTINFO or IP_RECVDSTADDR */ } } if(verbosity >= VERB_ALGO) p_ancil("receive_udp on interface", &rep); #endif /* S_SPLINT_S */ fptr_ok(fptr_whitelist_comm_point(rep.c->callback)); if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) { /* send back immediate reply */ (void)comm_point_send_udp_msg_if(rep.c, rep.c->buffer, (struct sockaddr*)&rep.addr, rep.addrlen, &rep); } if(!rep.c || rep.c->fd == -1) /* commpoint closed */ break; } #else (void)fd; (void)event; (void)arg; fatal_exit("recvmsg: No support for IPV6_PKTINFO; IP_PKTINFO or IP_RECVDSTADDR. " "Please disable interface-automatic"); #endif /* AF_INET6 && IPV6_PKTINFO && HAVE_RECVMSG */ } void comm_point_udp_callback(int fd, short event, void* arg) { struct comm_reply rep; ssize_t rcv; int i; struct sldns_buffer *buffer; rep.c = (struct comm_point*)arg; log_assert(rep.c->type == comm_udp); if(!(event&UB_EV_READ)) return; log_assert(rep.c && rep.c->buffer && rep.c->fd == fd); ub_comm_base_now(rep.c->ev->base); for(i=0; ibuffer); rep.addrlen = (socklen_t)sizeof(rep.addr); log_assert(fd != -1); log_assert(sldns_buffer_remaining(rep.c->buffer) > 0); rcv = recvfrom(fd, (void*)sldns_buffer_begin(rep.c->buffer), sldns_buffer_remaining(rep.c->buffer), 0, (struct sockaddr*)&rep.addr, &rep.addrlen); if(rcv == -1) { #ifndef USE_WINSOCK if(errno != EAGAIN && errno != EINTR && udp_recv_needs_log(errno)) log_err("recvfrom %d failed: %s", fd, strerror(errno)); #else if(WSAGetLastError() != WSAEINPROGRESS && WSAGetLastError() != WSAECONNRESET && WSAGetLastError()!= WSAEWOULDBLOCK && udp_recv_needs_log(WSAGetLastError())) log_err("recvfrom failed: %s", wsa_strerror(WSAGetLastError())); #endif return; } sldns_buffer_skip(rep.c->buffer, rcv); sldns_buffer_flip(rep.c->buffer); rep.srctype = 0; fptr_ok(fptr_whitelist_comm_point(rep.c->callback)); if((*rep.c->callback)(rep.c, rep.c->cb_arg, NETEVENT_NOERROR, &rep)) { /* send back immediate reply */ #ifdef USE_DNSCRYPT buffer = rep.c->dnscrypt_buffer; #else buffer = rep.c->buffer; #endif (void)comm_point_send_udp_msg(rep.c, buffer, (struct sockaddr*)&rep.addr, rep.addrlen, 0); } if(!rep.c || rep.c->fd != fd) /* commpoint closed to -1 or reused for another UDP port. Note rep.c cannot be reused with TCP fd. */ break; } } int adjusted_tcp_timeout(struct comm_point* c) { if(c->tcp_timeout_msec < TCP_QUERY_TIMEOUT_MINIMUM) return TCP_QUERY_TIMEOUT_MINIMUM; return c->tcp_timeout_msec; } /** Use a new tcp handler for new query fd, set to read query */ static void setup_tcp_handler(struct comm_point* c, int fd, int cur, int max) { int handler_usage; log_assert(c->type == comm_tcp || c->type == comm_http); log_assert(c->fd == -1); sldns_buffer_clear(c->buffer); #ifdef USE_DNSCRYPT if (c->dnscrypt) sldns_buffer_clear(c->dnscrypt_buffer); #endif c->tcp_is_reading = 1; c->tcp_byte_count = 0; c->tcp_keepalive = 0; /* if more than half the tcp handlers are in use, use a shorter * timeout for this TCP connection, we need to make space for * other connections to be able to get attention */ /* If > 50% TCP handler structures in use, set timeout to 1/100th * configured value. * If > 65%TCP handler structures in use, set to 1/500th configured * value. * If > 80% TCP handler structures in use, set to 0. * * If the timeout to use falls below 200 milliseconds, an actual * timeout of 200ms is used. */ handler_usage = (cur * 100) / max; if(handler_usage > 50 && handler_usage <= 65) c->tcp_timeout_msec /= 100; else if (handler_usage > 65 && handler_usage <= 80) c->tcp_timeout_msec /= 500; else if (handler_usage > 80) c->tcp_timeout_msec = 0; comm_point_start_listening(c, fd, adjusted_tcp_timeout(c)); } void comm_base_handle_slow_accept(int ATTR_UNUSED(fd), short ATTR_UNUSED(event), void* arg) { struct comm_base* b = (struct comm_base*)arg; /* timeout for the slow accept, re-enable accepts again */ if(b->start_accept) { verbose(VERB_ALGO, "wait is over, slow accept disabled"); fptr_ok(fptr_whitelist_start_accept(b->start_accept)); (*b->start_accept)(b->cb_arg); b->eb->slow_accept_enabled = 0; } } int comm_point_perform_accept(struct comm_point* c, struct sockaddr_storage* addr, socklen_t* addrlen) { int new_fd; *addrlen = (socklen_t)sizeof(*addr); #ifndef HAVE_ACCEPT4 new_fd = accept(c->fd, (struct sockaddr*)addr, addrlen); #else /* SOCK_NONBLOCK saves extra calls to fcntl for the same result */ new_fd = accept4(c->fd, (struct sockaddr*)addr, addrlen, SOCK_NONBLOCK); #endif if(new_fd == -1) { #ifndef USE_WINSOCK /* EINTR is signal interrupt. others are closed connection. */ if( errno == EINTR || errno == EAGAIN #ifdef EWOULDBLOCK || errno == EWOULDBLOCK #endif #ifdef ECONNABORTED || errno == ECONNABORTED #endif #ifdef EPROTO || errno == EPROTO #endif /* EPROTO */ ) return -1; #if defined(ENFILE) && defined(EMFILE) if(errno == ENFILE || errno == EMFILE) { /* out of file descriptors, likely outside of our * control. stop accept() calls for some time */ if(c->ev->base->stop_accept) { struct comm_base* b = c->ev->base; struct timeval tv; verbose(VERB_ALGO, "out of file descriptors: " "slow accept"); b->eb->slow_accept_enabled = 1; fptr_ok(fptr_whitelist_stop_accept( b->stop_accept)); (*b->stop_accept)(b->cb_arg); /* set timeout, no mallocs */ tv.tv_sec = NETEVENT_SLOW_ACCEPT_TIME/1000; tv.tv_usec = (NETEVENT_SLOW_ACCEPT_TIME%1000)*1000; b->eb->slow_accept = ub_event_new(b->eb->base, -1, UB_EV_TIMEOUT, comm_base_handle_slow_accept, b); if(b->eb->slow_accept == NULL) { /* we do not want to log here, because * that would spam the logfiles. * error: "event_base_set failed." */ } else if(ub_event_add(b->eb->slow_accept, &tv) != 0) { /* we do not want to log here, * error: "event_add failed." */ } } return -1; } #endif #else /* USE_WINSOCK */ if(WSAGetLastError() == WSAEINPROGRESS || WSAGetLastError() == WSAECONNRESET) return -1; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_READ); return -1; } #endif log_err_addr("accept failed", sock_strerror(errno), addr, *addrlen); return -1; } if(c->tcp_conn_limit && c->type == comm_tcp_accept) { c->tcl_addr = tcl_addr_lookup(c->tcp_conn_limit, addr, *addrlen); if(!tcl_new_connection(c->tcl_addr)) { if(verbosity >= 3) log_err_addr("accept rejected", "connection limit exceeded", addr, *addrlen); close(new_fd); return -1; } } #ifndef HAVE_ACCEPT4 fd_set_nonblock(new_fd); #endif return new_fd; } #ifdef USE_WINSOCK static long win_bio_cb(BIO *b, int oper, const char* ATTR_UNUSED(argp), #ifdef HAVE_BIO_SET_CALLBACK_EX size_t ATTR_UNUSED(len), #endif int ATTR_UNUSED(argi), long argl, #ifndef HAVE_BIO_SET_CALLBACK_EX long retvalue #else int retvalue, size_t* ATTR_UNUSED(processed) #endif ) { int wsa_err = WSAGetLastError(); /* store errcode before it is gone */ verbose(VERB_ALGO, "bio_cb %d, %s %s %s", oper, (oper&BIO_CB_RETURN)?"return":"before", (oper&BIO_CB_READ)?"read":((oper&BIO_CB_WRITE)?"write":"other"), wsa_err==WSAEWOULDBLOCK?"wsawb":""); /* on windows, check if previous operation caused EWOULDBLOCK */ if( (oper == (BIO_CB_READ|BIO_CB_RETURN) && argl == 0) || (oper == (BIO_CB_GETS|BIO_CB_RETURN) && argl == 0)) { if(wsa_err == WSAEWOULDBLOCK) ub_winsock_tcp_wouldblock((struct ub_event*) BIO_get_callback_arg(b), UB_EV_READ); } if( (oper == (BIO_CB_WRITE|BIO_CB_RETURN) && argl == 0) || (oper == (BIO_CB_PUTS|BIO_CB_RETURN) && argl == 0)) { if(wsa_err == WSAEWOULDBLOCK) ub_winsock_tcp_wouldblock((struct ub_event*) BIO_get_callback_arg(b), UB_EV_WRITE); } /* return original return value */ return retvalue; } /** set win bio callbacks for nonblocking operations */ void comm_point_tcp_win_bio_cb(struct comm_point* c, void* thessl) { SSL* ssl = (SSL*)thessl; /* set them both just in case, but usually they are the same BIO */ #ifdef HAVE_BIO_SET_CALLBACK_EX BIO_set_callback_ex(SSL_get_rbio(ssl), &win_bio_cb); #else BIO_set_callback(SSL_get_rbio(ssl), &win_bio_cb); #endif BIO_set_callback_arg(SSL_get_rbio(ssl), (char*)c->ev->ev); #ifdef HAVE_BIO_SET_CALLBACK_EX BIO_set_callback_ex(SSL_get_wbio(ssl), &win_bio_cb); #else BIO_set_callback(SSL_get_wbio(ssl), &win_bio_cb); #endif BIO_set_callback_arg(SSL_get_wbio(ssl), (char*)c->ev->ev); } #endif #ifdef HAVE_NGHTTP2 /** Create http2 session server. Per connection, after TCP accepted.*/ static int http2_session_server_create(struct http2_session* h2_session) { log_assert(h2_session->callbacks); h2_session->is_drop = 0; if(nghttp2_session_server_new(&h2_session->session, h2_session->callbacks, h2_session) == NGHTTP2_ERR_NOMEM) { log_err("failed to create nghttp2 session server"); return 0; } return 1; } /** Submit http2 setting to session. Once per session. */ static int http2_submit_settings(struct http2_session* h2_session) { int ret; nghttp2_settings_entry settings[1] = { {NGHTTP2_SETTINGS_MAX_CONCURRENT_STREAMS, h2_session->c->http2_max_streams}}; ret = nghttp2_submit_settings(h2_session->session, NGHTTP2_FLAG_NONE, settings, 1); if(ret) { verbose(VERB_QUERY, "http2: submit_settings failed, " "error: %s", nghttp2_strerror(ret)); return 0; } return 1; } #endif /* HAVE_NGHTTP2 */ void comm_point_tcp_accept_callback(int fd, short event, void* arg) { struct comm_point* c = (struct comm_point*)arg, *c_hdl; int new_fd; log_assert(c->type == comm_tcp_accept); if(!(event & UB_EV_READ)) { log_info("ignoring tcp accept event %d", (int)event); return; } ub_comm_base_now(c->ev->base); /* find free tcp handler. */ if(!c->tcp_free) { log_warn("accepted too many tcp, connections full"); return; } /* accept incoming connection. */ c_hdl = c->tcp_free; /* clear leftover flags from previous use, and then set the * correct event base for the event structure for libevent */ ub_event_free(c_hdl->ev->ev); c_hdl->ev->ev = NULL; if((c_hdl->type == comm_tcp && c_hdl->tcp_req_info) || c_hdl->type == comm_local || c_hdl->type == comm_raw) c_hdl->tcp_do_toggle_rw = 0; else c_hdl->tcp_do_toggle_rw = 1; if(c_hdl->type == comm_http) { #ifdef HAVE_NGHTTP2 if(!c_hdl->h2_session || !http2_session_server_create(c_hdl->h2_session)) { log_warn("failed to create nghttp2"); return; } if(!c_hdl->h2_session || !http2_submit_settings(c_hdl->h2_session)) { log_warn("failed to submit http2 settings"); return; } if(!c->ssl) { c_hdl->tcp_do_toggle_rw = 0; c_hdl->use_h2 = 1; } #endif c_hdl->ev->ev = ub_event_new(c_hdl->ev->base->eb->base, -1, UB_EV_PERSIST | UB_EV_READ | UB_EV_TIMEOUT, comm_point_http_handle_callback, c_hdl); } else { c_hdl->ev->ev = ub_event_new(c_hdl->ev->base->eb->base, -1, UB_EV_PERSIST | UB_EV_READ | UB_EV_TIMEOUT, comm_point_tcp_handle_callback, c_hdl); } if(!c_hdl->ev->ev) { log_warn("could not ub_event_new, dropped tcp"); return; } log_assert(fd != -1); (void)fd; new_fd = comm_point_perform_accept(c, &c_hdl->repinfo.addr, &c_hdl->repinfo.addrlen); if(new_fd == -1) return; if(c->ssl) { c_hdl->ssl = incoming_ssl_fd(c->ssl, new_fd); if(!c_hdl->ssl) { c_hdl->fd = new_fd; comm_point_close(c_hdl); return; } c_hdl->ssl_shake_state = comm_ssl_shake_read; #ifdef USE_WINSOCK comm_point_tcp_win_bio_cb(c_hdl, c_hdl->ssl); #endif } /* grab the tcp handler buffers */ c->cur_tcp_count++; c->tcp_free = c_hdl->tcp_free; c_hdl->tcp_free = NULL; if(!c->tcp_free) { /* stop accepting incoming queries for now. */ comm_point_stop_listening(c); } setup_tcp_handler(c_hdl, new_fd, c->cur_tcp_count, c->max_tcp_count); } /** Make tcp handler free for next assignment */ static void reclaim_tcp_handler(struct comm_point* c) { log_assert(c->type == comm_tcp); if(c->ssl) { #ifdef HAVE_SSL SSL_shutdown(c->ssl); SSL_free(c->ssl); c->ssl = NULL; #endif } comm_point_close(c); if(c->tcp_parent) { if(c != c->tcp_parent->tcp_free) { c->tcp_parent->cur_tcp_count--; c->tcp_free = c->tcp_parent->tcp_free; c->tcp_parent->tcp_free = c; } if(!c->tcp_free) { /* re-enable listening on accept socket */ comm_point_start_listening(c->tcp_parent, -1, -1); } } c->tcp_more_read_again = NULL; c->tcp_more_write_again = NULL; c->tcp_byte_count = 0; sldns_buffer_clear(c->buffer); } /** do the callback when writing is done */ static void tcp_callback_writer(struct comm_point* c) { log_assert(c->type == comm_tcp); if(!c->tcp_write_and_read) { sldns_buffer_clear(c->buffer); c->tcp_byte_count = 0; } if(c->tcp_do_toggle_rw) c->tcp_is_reading = 1; /* switch from listening(write) to listening(read) */ if(c->tcp_req_info) { tcp_req_info_handle_writedone(c->tcp_req_info); } else { comm_point_stop_listening(c); if(c->tcp_write_and_read) { fptr_ok(fptr_whitelist_comm_point(c->callback)); if( (*c->callback)(c, c->cb_arg, NETEVENT_PKT_WRITTEN, &c->repinfo) ) { comm_point_start_listening(c, -1, adjusted_tcp_timeout(c)); } } else { comm_point_start_listening(c, -1, adjusted_tcp_timeout(c)); } } } /** do the callback when reading is done */ static void tcp_callback_reader(struct comm_point* c) { log_assert(c->type == comm_tcp || c->type == comm_local); sldns_buffer_flip(c->buffer); if(c->tcp_do_toggle_rw) c->tcp_is_reading = 0; c->tcp_byte_count = 0; if(c->tcp_req_info) { tcp_req_info_handle_readdone(c->tcp_req_info); } else { if(c->type == comm_tcp) comm_point_stop_listening(c); fptr_ok(fptr_whitelist_comm_point(c->callback)); if( (*c->callback)(c, c->cb_arg, NETEVENT_NOERROR, &c->repinfo) ) { comm_point_start_listening(c, -1, adjusted_tcp_timeout(c)); } } } #ifdef HAVE_SSL /** true if the ssl handshake error has to be squelched from the logs */ int squelch_err_ssl_handshake(unsigned long err) { if(verbosity >= VERB_QUERY) return 0; /* only squelch on low verbosity */ if(ERR_GET_LIB(err) == ERR_LIB_SSL && (ERR_GET_REASON(err) == SSL_R_HTTPS_PROXY_REQUEST || ERR_GET_REASON(err) == SSL_R_HTTP_REQUEST || ERR_GET_REASON(err) == SSL_R_WRONG_VERSION_NUMBER || ERR_GET_REASON(err) == SSL_R_SSLV3_ALERT_BAD_CERTIFICATE #ifdef SSL_F_TLS_POST_PROCESS_CLIENT_HELLO || ERR_GET_REASON(err) == SSL_R_NO_SHARED_CIPHER #endif #ifdef SSL_F_TLS_EARLY_POST_PROCESS_CLIENT_HELLO || ERR_GET_REASON(err) == SSL_R_UNKNOWN_PROTOCOL || ERR_GET_REASON(err) == SSL_R_UNSUPPORTED_PROTOCOL # ifdef SSL_R_VERSION_TOO_LOW || ERR_GET_REASON(err) == SSL_R_VERSION_TOO_LOW # endif #endif )) return 1; return 0; } #endif /* HAVE_SSL */ /** continue ssl handshake */ #ifdef HAVE_SSL static int ssl_handshake(struct comm_point* c) { int r; if(c->ssl_shake_state == comm_ssl_shake_hs_read) { /* read condition satisfied back to writing */ comm_point_listen_for_rw(c, 0, 1); c->ssl_shake_state = comm_ssl_shake_none; return 1; } if(c->ssl_shake_state == comm_ssl_shake_hs_write) { /* write condition satisfied, back to reading */ comm_point_listen_for_rw(c, 1, 0); c->ssl_shake_state = comm_ssl_shake_none; return 1; } ERR_clear_error(); r = SSL_do_handshake(c->ssl); if(r != 1) { int want = SSL_get_error(c->ssl, r); if(want == SSL_ERROR_WANT_READ) { if(c->ssl_shake_state == comm_ssl_shake_read) return 1; c->ssl_shake_state = comm_ssl_shake_read; comm_point_listen_for_rw(c, 1, 0); return 1; } else if(want == SSL_ERROR_WANT_WRITE) { if(c->ssl_shake_state == comm_ssl_shake_write) return 1; c->ssl_shake_state = comm_ssl_shake_write; comm_point_listen_for_rw(c, 0, 1); return 1; } else if(r == 0) { return 0; /* closed */ } else if(want == SSL_ERROR_SYSCALL) { /* SYSCALL and errno==0 means closed uncleanly */ #ifdef EPIPE if(errno == EPIPE && verbosity < 2) return 0; /* silence 'broken pipe' */ #endif #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif if(!tcp_connect_errno_needs_log( (struct sockaddr*)&c->repinfo.addr, c->repinfo.addrlen)) return 0; /* silence connect failures that show up because after connect this is the first system call that accesses the socket */ if(errno != 0) log_err("SSL_handshake syscall: %s", strerror(errno)); return 0; } else { unsigned long err = ERR_get_error(); if(!squelch_err_ssl_handshake(err)) { log_crypto_err_code("ssl handshake failed", err); log_addr(VERB_OPS, "ssl handshake failed", &c->repinfo.addr, c->repinfo.addrlen); } return 0; } } /* this is where peer verification could take place */ if((SSL_get_verify_mode(c->ssl)&SSL_VERIFY_PEER)) { /* verification */ if(SSL_get_verify_result(c->ssl) == X509_V_OK) { #ifdef HAVE_SSL_GET1_PEER_CERTIFICATE X509* x = SSL_get1_peer_certificate(c->ssl); #else X509* x = SSL_get_peer_certificate(c->ssl); #endif if(!x) { log_addr(VERB_ALGO, "SSL connection failed: " "no certificate", &c->repinfo.addr, c->repinfo.addrlen); return 0; } log_cert(VERB_ALGO, "peer certificate", x); #ifdef HAVE_SSL_GET0_PEERNAME if(SSL_get0_peername(c->ssl)) { char buf[255]; snprintf(buf, sizeof(buf), "SSL connection " "to %s authenticated", SSL_get0_peername(c->ssl)); log_addr(VERB_ALGO, buf, &c->repinfo.addr, c->repinfo.addrlen); } else { #endif log_addr(VERB_ALGO, "SSL connection " "authenticated", &c->repinfo.addr, c->repinfo.addrlen); #ifdef HAVE_SSL_GET0_PEERNAME } #endif X509_free(x); } else { #ifdef HAVE_SSL_GET1_PEER_CERTIFICATE X509* x = SSL_get1_peer_certificate(c->ssl); #else X509* x = SSL_get_peer_certificate(c->ssl); #endif if(x) { log_cert(VERB_ALGO, "peer certificate", x); X509_free(x); } log_addr(VERB_ALGO, "SSL connection failed: " "failed to authenticate", &c->repinfo.addr, c->repinfo.addrlen); return 0; } } else { /* unauthenticated, the verify peer flag was not set * in c->ssl when the ssl object was created from ssl_ctx */ log_addr(VERB_ALGO, "SSL connection", &c->repinfo.addr, c->repinfo.addrlen); } #ifdef HAVE_SSL_GET0_ALPN_SELECTED /* check if http2 use is negotiated */ if(c->type == comm_http && c->h2_session) { const unsigned char *alpn; unsigned int alpnlen = 0; SSL_get0_alpn_selected(c->ssl, &alpn, &alpnlen); if(alpnlen == 2 && memcmp("h2", alpn, 2) == 0) { /* connection upgraded to HTTP2 */ c->tcp_do_toggle_rw = 0; c->use_h2 = 1; } } #endif /* setup listen rw correctly */ if(c->tcp_is_reading) { if(c->ssl_shake_state != comm_ssl_shake_read) comm_point_listen_for_rw(c, 1, 0); } else { comm_point_listen_for_rw(c, 0, 1); } c->ssl_shake_state = comm_ssl_shake_none; return 1; } #endif /* HAVE_SSL */ /** ssl read callback on TCP */ static int ssl_handle_read(struct comm_point* c) { #ifdef HAVE_SSL int r; if(c->ssl_shake_state != comm_ssl_shake_none) { if(!ssl_handshake(c)) return 0; if(c->ssl_shake_state != comm_ssl_shake_none) return 1; } if(c->tcp_byte_count < sizeof(uint16_t)) { /* read length bytes */ ERR_clear_error(); if((r=SSL_read(c->ssl, (void*)sldns_buffer_at(c->buffer, c->tcp_byte_count), (int)(sizeof(uint16_t) - c->tcp_byte_count))) <= 0) { int want = SSL_get_error(c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { if(c->tcp_req_info) return tcp_req_info_handle_read_close(c->tcp_req_info); return 0; /* shutdown, closed */ } else if(want == SSL_ERROR_WANT_READ) { #ifdef USE_WINSOCK ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_READ); #endif return 1; /* read more later */ } else if(want == SSL_ERROR_WANT_WRITE) { c->ssl_shake_state = comm_ssl_shake_hs_write; comm_point_listen_for_rw(c, 0, 1); return 1; } else if(want == SSL_ERROR_SYSCALL) { #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif if(errno != 0) log_err("SSL_read syscall: %s", strerror(errno)); return 0; } log_crypto_err("could not SSL_read"); return 0; } c->tcp_byte_count += r; if(c->tcp_byte_count < sizeof(uint16_t)) return 1; if(sldns_buffer_read_u16_at(c->buffer, 0) > sldns_buffer_capacity(c->buffer)) { verbose(VERB_QUERY, "ssl: dropped larger than buffer"); return 0; } sldns_buffer_set_limit(c->buffer, sldns_buffer_read_u16_at(c->buffer, 0)); if(sldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE) { verbose(VERB_QUERY, "ssl: dropped bogus too short."); return 0; } sldns_buffer_skip(c->buffer, (ssize_t)(c->tcp_byte_count-sizeof(uint16_t))); verbose(VERB_ALGO, "Reading ssl tcp query of length %d", (int)sldns_buffer_limit(c->buffer)); } if(sldns_buffer_remaining(c->buffer) > 0) { ERR_clear_error(); r = SSL_read(c->ssl, (void*)sldns_buffer_current(c->buffer), (int)sldns_buffer_remaining(c->buffer)); if(r <= 0) { int want = SSL_get_error(c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { if(c->tcp_req_info) return tcp_req_info_handle_read_close(c->tcp_req_info); return 0; /* shutdown, closed */ } else if(want == SSL_ERROR_WANT_READ) { #ifdef USE_WINSOCK ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_READ); #endif return 1; /* read more later */ } else if(want == SSL_ERROR_WANT_WRITE) { c->ssl_shake_state = comm_ssl_shake_hs_write; comm_point_listen_for_rw(c, 0, 1); return 1; } else if(want == SSL_ERROR_SYSCALL) { #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif if(errno != 0) log_err("SSL_read syscall: %s", strerror(errno)); return 0; } log_crypto_err("could not SSL_read"); return 0; } sldns_buffer_skip(c->buffer, (ssize_t)r); } if(sldns_buffer_remaining(c->buffer) <= 0) { tcp_callback_reader(c); } return 1; #else (void)c; return 0; #endif /* HAVE_SSL */ } /** ssl write callback on TCP */ static int ssl_handle_write(struct comm_point* c) { #ifdef HAVE_SSL int r; if(c->ssl_shake_state != comm_ssl_shake_none) { if(!ssl_handshake(c)) return 0; if(c->ssl_shake_state != comm_ssl_shake_none) return 1; } /* ignore return, if fails we may simply block */ (void)SSL_set_mode(c->ssl, (long)SSL_MODE_ENABLE_PARTIAL_WRITE); if((c->tcp_write_and_read?c->tcp_write_byte_count:c->tcp_byte_count) < sizeof(uint16_t)) { uint16_t len = htons(c->tcp_write_and_read?c->tcp_write_pkt_len:sldns_buffer_limit(c->buffer)); ERR_clear_error(); if(c->tcp_write_and_read) { if(c->tcp_write_pkt_len + 2 < LDNS_RR_BUF_SIZE) { /* combine the tcp length and the query for * write, this emulates writev */ uint8_t buf[LDNS_RR_BUF_SIZE]; memmove(buf, &len, sizeof(uint16_t)); memmove(buf+sizeof(uint16_t), c->tcp_write_pkt, c->tcp_write_pkt_len); r = SSL_write(c->ssl, (void*)(buf+c->tcp_write_byte_count), c->tcp_write_pkt_len + 2 - c->tcp_write_byte_count); } else { r = SSL_write(c->ssl, (void*)(((uint8_t*)&len)+c->tcp_write_byte_count), (int)(sizeof(uint16_t)-c->tcp_write_byte_count)); } } else if(sizeof(uint16_t)+sldns_buffer_remaining(c->buffer) < LDNS_RR_BUF_SIZE) { /* combine the tcp length and the query for write, * this emulates writev */ uint8_t buf[LDNS_RR_BUF_SIZE]; memmove(buf, &len, sizeof(uint16_t)); memmove(buf+sizeof(uint16_t), sldns_buffer_current(c->buffer), sldns_buffer_remaining(c->buffer)); r = SSL_write(c->ssl, (void*)(buf+c->tcp_byte_count), (int)(sizeof(uint16_t)+ sldns_buffer_remaining(c->buffer) - c->tcp_byte_count)); } else { r = SSL_write(c->ssl, (void*)(((uint8_t*)&len)+c->tcp_byte_count), (int)(sizeof(uint16_t)-c->tcp_byte_count)); } if(r <= 0) { int want = SSL_get_error(c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { return 0; /* closed */ } else if(want == SSL_ERROR_WANT_READ) { c->ssl_shake_state = comm_ssl_shake_hs_read; comm_point_listen_for_rw(c, 1, 0); return 1; /* wait for read condition */ } else if(want == SSL_ERROR_WANT_WRITE) { #ifdef USE_WINSOCK ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); #endif return 1; /* write more later */ } else if(want == SSL_ERROR_SYSCALL) { #ifdef EPIPE if(errno == EPIPE && verbosity < 2) return 0; /* silence 'broken pipe' */ #endif if(errno != 0) log_err("SSL_write syscall: %s", strerror(errno)); return 0; } log_crypto_err("could not SSL_write"); return 0; } if(c->tcp_write_and_read) { c->tcp_write_byte_count += r; if(c->tcp_write_byte_count < sizeof(uint16_t)) return 1; } else { c->tcp_byte_count += r; if(c->tcp_byte_count < sizeof(uint16_t)) return 1; sldns_buffer_set_position(c->buffer, c->tcp_byte_count - sizeof(uint16_t)); } if((!c->tcp_write_and_read && sldns_buffer_remaining(c->buffer) == 0) || (c->tcp_write_and_read && c->tcp_write_byte_count == c->tcp_write_pkt_len + 2)) { tcp_callback_writer(c); return 1; } } log_assert(c->tcp_write_and_read || sldns_buffer_remaining(c->buffer) > 0); log_assert(!c->tcp_write_and_read || c->tcp_write_byte_count < c->tcp_write_pkt_len + 2); ERR_clear_error(); if(c->tcp_write_and_read) { r = SSL_write(c->ssl, (void*)(c->tcp_write_pkt + c->tcp_write_byte_count - 2), (int)(c->tcp_write_pkt_len + 2 - c->tcp_write_byte_count)); } else { r = SSL_write(c->ssl, (void*)sldns_buffer_current(c->buffer), (int)sldns_buffer_remaining(c->buffer)); } if(r <= 0) { int want = SSL_get_error(c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { return 0; /* closed */ } else if(want == SSL_ERROR_WANT_READ) { c->ssl_shake_state = comm_ssl_shake_hs_read; comm_point_listen_for_rw(c, 1, 0); return 1; /* wait for read condition */ } else if(want == SSL_ERROR_WANT_WRITE) { #ifdef USE_WINSOCK ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); #endif return 1; /* write more later */ } else if(want == SSL_ERROR_SYSCALL) { #ifdef EPIPE if(errno == EPIPE && verbosity < 2) return 0; /* silence 'broken pipe' */ #endif if(errno != 0) log_err("SSL_write syscall: %s", strerror(errno)); return 0; } log_crypto_err("could not SSL_write"); return 0; } if(c->tcp_write_and_read) { c->tcp_write_byte_count += r; } else { sldns_buffer_skip(c->buffer, (ssize_t)r); } if((!c->tcp_write_and_read && sldns_buffer_remaining(c->buffer) == 0) || (c->tcp_write_and_read && c->tcp_write_byte_count == c->tcp_write_pkt_len + 2)) { tcp_callback_writer(c); } return 1; #else (void)c; return 0; #endif /* HAVE_SSL */ } /** handle ssl tcp connection with dns contents */ static int ssl_handle_it(struct comm_point* c, int is_write) { /* handle case where renegotiation wants read during write call * or write during read calls */ if(is_write && c->ssl_shake_state == comm_ssl_shake_hs_write) return ssl_handle_read(c); else if(!is_write && c->ssl_shake_state == comm_ssl_shake_hs_read) return ssl_handle_write(c); /* handle read events for read operation and write events for a * write operation */ else if(!is_write) return ssl_handle_read(c); return ssl_handle_write(c); } /** Handle tcp reading callback. * @param fd: file descriptor of socket. * @param c: comm point to read from into buffer. * @param short_ok: if true, very short packets are OK (for comm_local). * @return: 0 on error */ static int comm_point_tcp_handle_read(int fd, struct comm_point* c, int short_ok) { ssize_t r; log_assert(c->type == comm_tcp || c->type == comm_local); if(c->ssl) return ssl_handle_it(c, 0); if(!c->tcp_is_reading && !c->tcp_write_and_read) return 0; log_assert(fd != -1); if(c->tcp_byte_count < sizeof(uint16_t)) { /* read length bytes */ r = recv(fd,(void*)sldns_buffer_at(c->buffer,c->tcp_byte_count), sizeof(uint16_t)-c->tcp_byte_count, 0); if(r == 0) { if(c->tcp_req_info) return tcp_req_info_handle_read_close(c->tcp_req_info); return 0; } else if(r == -1) { #ifndef USE_WINSOCK if(errno == EINTR || errno == EAGAIN) return 1; #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif #ifdef ECONNREFUSED if(errno == ECONNREFUSED && verbosity < 2) return 0; /* silence reset by peer */ #endif #ifdef ENETUNREACH if(errno == ENETUNREACH && verbosity < 2) return 0; /* silence it */ #endif #ifdef EHOSTDOWN if(errno == EHOSTDOWN && verbosity < 2) return 0; /* silence it */ #endif #ifdef EHOSTUNREACH if(errno == EHOSTUNREACH && verbosity < 2) return 0; /* silence it */ #endif #ifdef ENETDOWN if(errno == ENETDOWN && verbosity < 2) return 0; /* silence it */ #endif #ifdef EACCES if(errno == EACCES && verbosity < 2) return 0; /* silence it */ #endif #ifdef ENOTCONN if(errno == ENOTCONN) { log_err_addr("read (in tcp s) failed and this could be because TCP Fast Open is enabled [--disable-tfo-client --disable-tfo-server] but does not work", sock_strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); return 0; } #endif #else /* USE_WINSOCK */ if(WSAGetLastError() == WSAECONNREFUSED && verbosity < 2) return 0; if(WSAGetLastError() == WSAEHOSTDOWN && verbosity < 2) return 0; if(WSAGetLastError() == WSAEHOSTUNREACH && verbosity < 2) return 0; if(WSAGetLastError() == WSAENETDOWN && verbosity < 2) return 0; if(WSAGetLastError() == WSAENETUNREACH && verbosity < 2) return 0; if(WSAGetLastError() == WSAECONNRESET) return 0; if(WSAGetLastError() == WSAEINPROGRESS) return 1; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_READ); return 1; } #endif log_err_addr("read (in tcp s)", sock_strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); return 0; } c->tcp_byte_count += r; if(c->tcp_byte_count != sizeof(uint16_t)) return 1; if(sldns_buffer_read_u16_at(c->buffer, 0) > sldns_buffer_capacity(c->buffer)) { verbose(VERB_QUERY, "tcp: dropped larger than buffer"); return 0; } sldns_buffer_set_limit(c->buffer, sldns_buffer_read_u16_at(c->buffer, 0)); if(!short_ok && sldns_buffer_limit(c->buffer) < LDNS_HEADER_SIZE) { verbose(VERB_QUERY, "tcp: dropped bogus too short."); return 0; } verbose(VERB_ALGO, "Reading tcp query of length %d", (int)sldns_buffer_limit(c->buffer)); } if(sldns_buffer_remaining(c->buffer) == 0) log_err("in comm_point_tcp_handle_read buffer_remaining is not > 0 as expected, continuing with (harmless) 0 length recv"); r = recv(fd, (void*)sldns_buffer_current(c->buffer), sldns_buffer_remaining(c->buffer), 0); if(r == 0) { if(c->tcp_req_info) return tcp_req_info_handle_read_close(c->tcp_req_info); return 0; } else if(r == -1) { #ifndef USE_WINSOCK if(errno == EINTR || errno == EAGAIN) return 1; #else /* USE_WINSOCK */ if(WSAGetLastError() == WSAECONNRESET) return 0; if(WSAGetLastError() == WSAEINPROGRESS) return 1; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_READ); return 1; } #endif log_err_addr("read (in tcp r)", sock_strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); return 0; } sldns_buffer_skip(c->buffer, r); if(sldns_buffer_remaining(c->buffer) <= 0) { tcp_callback_reader(c); } return 1; } /** * Handle tcp writing callback. * @param fd: file descriptor of socket. * @param c: comm point to write buffer out of. * @return: 0 on error */ static int comm_point_tcp_handle_write(int fd, struct comm_point* c) { ssize_t r; struct sldns_buffer *buffer; log_assert(c->type == comm_tcp); #ifdef USE_DNSCRYPT buffer = c->dnscrypt_buffer; #else buffer = c->buffer; #endif if(c->tcp_is_reading && !c->ssl && !c->tcp_write_and_read) return 0; log_assert(fd != -1); if(((!c->tcp_write_and_read && c->tcp_byte_count == 0) || (c->tcp_write_and_read && c->tcp_write_byte_count == 0)) && c->tcp_check_nb_connect) { /* check for pending error from nonblocking connect */ /* from Stevens, unix network programming, vol1, 3rd ed, p450*/ int error = 0; socklen_t len = (socklen_t)sizeof(error); if(getsockopt(fd, SOL_SOCKET, SO_ERROR, (void*)&error, &len) < 0){ #ifndef USE_WINSOCK error = errno; /* on solaris errno is error */ #else /* USE_WINSOCK */ error = WSAGetLastError(); #endif } #ifndef USE_WINSOCK #if defined(EINPROGRESS) && defined(EWOULDBLOCK) if(error == EINPROGRESS || error == EWOULDBLOCK) return 1; /* try again later */ else #endif if(error != 0 && verbosity < 2) return 0; /* silence lots of chatter in the logs */ else if(error != 0) { log_err_addr("tcp connect", strerror(error), &c->repinfo.addr, c->repinfo.addrlen); #else /* USE_WINSOCK */ /* examine error */ if(error == WSAEINPROGRESS) return 1; else if(error == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); return 1; } else if(error != 0 && verbosity < 2) return 0; else if(error != 0) { log_err_addr("tcp connect", wsa_strerror(error), &c->repinfo.addr, c->repinfo.addrlen); #endif /* USE_WINSOCK */ return 0; } } if(c->ssl) return ssl_handle_it(c, 1); #ifdef USE_MSG_FASTOPEN /* Only try this on first use of a connection that uses tfo, otherwise fall through to normal write */ /* Also, TFO support on WINDOWS not implemented at the moment */ if(c->tcp_do_fastopen == 1) { /* this form of sendmsg() does both a connect() and send() so need to look for various flavours of error*/ uint16_t len = htons(c->tcp_write_and_read?c->tcp_write_pkt_len:sldns_buffer_limit(buffer)); struct msghdr msg; struct iovec iov[2]; c->tcp_do_fastopen = 0; memset(&msg, 0, sizeof(msg)); if(c->tcp_write_and_read) { iov[0].iov_base = (uint8_t*)&len + c->tcp_write_byte_count; iov[0].iov_len = sizeof(uint16_t) - c->tcp_write_byte_count; iov[1].iov_base = c->tcp_write_pkt; iov[1].iov_len = c->tcp_write_pkt_len; } else { iov[0].iov_base = (uint8_t*)&len + c->tcp_byte_count; iov[0].iov_len = sizeof(uint16_t) - c->tcp_byte_count; iov[1].iov_base = sldns_buffer_begin(buffer); iov[1].iov_len = sldns_buffer_limit(buffer); } log_assert(iov[0].iov_len > 0); msg.msg_name = &c->repinfo.addr; msg.msg_namelen = c->repinfo.addrlen; msg.msg_iov = iov; msg.msg_iovlen = 2; r = sendmsg(fd, &msg, MSG_FASTOPEN); if (r == -1) { #if defined(EINPROGRESS) && defined(EWOULDBLOCK) /* Handshake is underway, maybe because no TFO cookie available. Come back to write the message*/ if(errno == EINPROGRESS || errno == EWOULDBLOCK) return 1; #endif if(errno == EINTR || errno == EAGAIN) return 1; /* Not handling EISCONN here as shouldn't ever hit that case.*/ if(errno != EPIPE #ifdef EOPNOTSUPP /* if /proc/sys/net/ipv4/tcp_fastopen is * disabled on Linux, sendmsg may return * 'Operation not supported', if so * fallthrough to ordinary connect. */ && errno != EOPNOTSUPP #endif && errno != 0) { if(verbosity < 2) return 0; /* silence lots of chatter in the logs */ log_err_addr("tcp sendmsg", strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); return 0; } verbose(VERB_ALGO, "tcp sendmsg for fastopen failed (with %s), try normal connect", strerror(errno)); /* fallthrough to nonFASTOPEN * (MSG_FASTOPEN on Linux 3 produces EPIPE) * we need to perform connect() */ if(connect(fd, (struct sockaddr *)&c->repinfo.addr, c->repinfo.addrlen) == -1) { #ifdef EINPROGRESS if(errno == EINPROGRESS) return 1; /* wait until connect done*/ #endif #ifdef USE_WINSOCK if(WSAGetLastError() == WSAEINPROGRESS || WSAGetLastError() == WSAEWOULDBLOCK) return 1; /* wait until connect done*/ #endif if(tcp_connect_errno_needs_log( (struct sockaddr *)&c->repinfo.addr, c->repinfo.addrlen)) { log_err_addr("outgoing tcp: connect after EPIPE for fastopen", strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); } return 0; } } else { if(c->tcp_write_and_read) { c->tcp_write_byte_count += r; if(c->tcp_write_byte_count < sizeof(uint16_t)) return 1; } else { c->tcp_byte_count += r; if(c->tcp_byte_count < sizeof(uint16_t)) return 1; sldns_buffer_set_position(buffer, c->tcp_byte_count - sizeof(uint16_t)); } if((!c->tcp_write_and_read && sldns_buffer_remaining(buffer) == 0) || (c->tcp_write_and_read && c->tcp_write_byte_count == c->tcp_write_pkt_len + 2)) { tcp_callback_writer(c); return 1; } } } #endif /* USE_MSG_FASTOPEN */ if((c->tcp_write_and_read?c->tcp_write_byte_count:c->tcp_byte_count) < sizeof(uint16_t)) { uint16_t len = htons(c->tcp_write_and_read?c->tcp_write_pkt_len:sldns_buffer_limit(buffer)); #ifdef HAVE_WRITEV struct iovec iov[2]; if(c->tcp_write_and_read) { iov[0].iov_base = (uint8_t*)&len + c->tcp_write_byte_count; iov[0].iov_len = sizeof(uint16_t) - c->tcp_write_byte_count; iov[1].iov_base = c->tcp_write_pkt; iov[1].iov_len = c->tcp_write_pkt_len; } else { iov[0].iov_base = (uint8_t*)&len + c->tcp_byte_count; iov[0].iov_len = sizeof(uint16_t) - c->tcp_byte_count; iov[1].iov_base = sldns_buffer_begin(buffer); iov[1].iov_len = sldns_buffer_limit(buffer); } log_assert(iov[0].iov_len > 0); r = writev(fd, iov, 2); #else /* HAVE_WRITEV */ if(c->tcp_write_and_read) { r = send(fd, (void*)(((uint8_t*)&len)+c->tcp_write_byte_count), sizeof(uint16_t)-c->tcp_write_byte_count, 0); } else { r = send(fd, (void*)(((uint8_t*)&len)+c->tcp_byte_count), sizeof(uint16_t)-c->tcp_byte_count, 0); } #endif /* HAVE_WRITEV */ if(r == -1) { #ifndef USE_WINSOCK # ifdef EPIPE if(errno == EPIPE && verbosity < 2) return 0; /* silence 'broken pipe' */ #endif if(errno == EINTR || errno == EAGAIN) return 1; #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif # ifdef HAVE_WRITEV log_err_addr("tcp writev", strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); # else /* HAVE_WRITEV */ log_err_addr("tcp send s", strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); # endif /* HAVE_WRITEV */ #else if(WSAGetLastError() == WSAENOTCONN) return 1; if(WSAGetLastError() == WSAEINPROGRESS) return 1; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); return 1; } if(WSAGetLastError() == WSAECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ log_err_addr("tcp send s", wsa_strerror(WSAGetLastError()), &c->repinfo.addr, c->repinfo.addrlen); #endif return 0; } if(c->tcp_write_and_read) { c->tcp_write_byte_count += r; if(c->tcp_write_byte_count < sizeof(uint16_t)) return 1; } else { c->tcp_byte_count += r; if(c->tcp_byte_count < sizeof(uint16_t)) return 1; sldns_buffer_set_position(buffer, c->tcp_byte_count - sizeof(uint16_t)); } if((!c->tcp_write_and_read && sldns_buffer_remaining(buffer) == 0) || (c->tcp_write_and_read && c->tcp_write_byte_count == c->tcp_write_pkt_len + 2)) { tcp_callback_writer(c); return 1; } } log_assert(c->tcp_write_and_read || sldns_buffer_remaining(buffer) > 0); log_assert(!c->tcp_write_and_read || c->tcp_write_byte_count < c->tcp_write_pkt_len + 2); if(c->tcp_write_and_read) { r = send(fd, (void*)(c->tcp_write_pkt + c->tcp_write_byte_count - 2), c->tcp_write_pkt_len + 2 - c->tcp_write_byte_count, 0); } else { r = send(fd, (void*)sldns_buffer_current(buffer), sldns_buffer_remaining(buffer), 0); } if(r == -1) { #ifndef USE_WINSOCK if(errno == EINTR || errno == EAGAIN) return 1; #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif #else if(WSAGetLastError() == WSAEINPROGRESS) return 1; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); return 1; } if(WSAGetLastError() == WSAECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif log_err_addr("tcp send r", sock_strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); return 0; } if(c->tcp_write_and_read) { c->tcp_write_byte_count += r; } else { sldns_buffer_skip(buffer, r); } if((!c->tcp_write_and_read && sldns_buffer_remaining(buffer) == 0) || (c->tcp_write_and_read && c->tcp_write_byte_count == c->tcp_write_pkt_len + 2)) { tcp_callback_writer(c); } return 1; } /** read again to drain buffers when there could be more to read */ static void tcp_req_info_read_again(int fd, struct comm_point* c) { while(c->tcp_req_info->read_again) { int r; c->tcp_req_info->read_again = 0; if(c->tcp_is_reading) r = comm_point_tcp_handle_read(fd, c, 0); else r = comm_point_tcp_handle_write(fd, c); if(!r) { reclaim_tcp_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } return; } } } /** read again to drain buffers when there could be more to read */ static void tcp_more_read_again(int fd, struct comm_point* c) { /* if the packet is done, but another one could be waiting on * the connection, the callback signals this, and we try again */ /* this continues until the read routines get EAGAIN or so, * and thus does not call the callback, and the bool is 0 */ int* moreread = c->tcp_more_read_again; while(moreread && *moreread) { *moreread = 0; if(!comm_point_tcp_handle_read(fd, c, 0)) { reclaim_tcp_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } return; } } } /** write again to fill up when there could be more to write */ static void tcp_more_write_again(int fd, struct comm_point* c) { /* if the packet is done, but another is waiting to be written, * the callback signals it and we try again. */ /* this continues until the write routines get EAGAIN or so, * and thus does not call the callback, and the bool is 0 */ int* morewrite = c->tcp_more_write_again; while(morewrite && *morewrite) { *morewrite = 0; if(!comm_point_tcp_handle_write(fd, c)) { reclaim_tcp_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } return; } } } void comm_point_tcp_handle_callback(int fd, short event, void* arg) { struct comm_point* c = (struct comm_point*)arg; log_assert(c->type == comm_tcp); ub_comm_base_now(c->ev->base); #ifdef USE_DNSCRYPT /* Initialize if this is a dnscrypt socket */ if(c->tcp_parent) { c->dnscrypt = c->tcp_parent->dnscrypt; } if(c->dnscrypt && c->dnscrypt_buffer == c->buffer) { c->dnscrypt_buffer = sldns_buffer_new(sldns_buffer_capacity(c->buffer)); if(!c->dnscrypt_buffer) { log_err("Could not allocate dnscrypt buffer"); reclaim_tcp_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } return; } } #endif if(event&UB_EV_TIMEOUT) { verbose(VERB_QUERY, "tcp took too long, dropped"); reclaim_tcp_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_TIMEOUT, NULL); } return; } if(event&UB_EV_READ #ifdef USE_MSG_FASTOPEN && !(c->tcp_do_fastopen && (event&UB_EV_WRITE)) #endif ) { int has_tcpq = (c->tcp_req_info != NULL); int* moreread = c->tcp_more_read_again; if(!comm_point_tcp_handle_read(fd, c, 0)) { reclaim_tcp_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } return; } if(has_tcpq && c->tcp_req_info && c->tcp_req_info->read_again) tcp_req_info_read_again(fd, c); if(moreread && *moreread) tcp_more_read_again(fd, c); return; } if(event&UB_EV_WRITE) { int has_tcpq = (c->tcp_req_info != NULL); int* morewrite = c->tcp_more_write_again; if(!comm_point_tcp_handle_write(fd, c)) { reclaim_tcp_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } return; } if(has_tcpq && c->tcp_req_info && c->tcp_req_info->read_again) tcp_req_info_read_again(fd, c); if(morewrite && *morewrite) tcp_more_write_again(fd, c); return; } log_err("Ignored event %d for tcphdl.", event); } /** Make http handler free for next assignment */ static void reclaim_http_handler(struct comm_point* c) { log_assert(c->type == comm_http); if(c->ssl) { #ifdef HAVE_SSL SSL_shutdown(c->ssl); SSL_free(c->ssl); c->ssl = NULL; #endif } comm_point_close(c); if(c->tcp_parent) { if(c != c->tcp_parent->tcp_free) { c->tcp_parent->cur_tcp_count--; c->tcp_free = c->tcp_parent->tcp_free; c->tcp_parent->tcp_free = c; } if(!c->tcp_free) { /* re-enable listening on accept socket */ comm_point_start_listening(c->tcp_parent, -1, -1); } } } /** read more data for http (with ssl) */ static int ssl_http_read_more(struct comm_point* c) { #ifdef HAVE_SSL int r; log_assert(sldns_buffer_remaining(c->buffer) > 0); ERR_clear_error(); r = SSL_read(c->ssl, (void*)sldns_buffer_current(c->buffer), (int)sldns_buffer_remaining(c->buffer)); if(r <= 0) { int want = SSL_get_error(c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { return 0; /* shutdown, closed */ } else if(want == SSL_ERROR_WANT_READ) { return 1; /* read more later */ } else if(want == SSL_ERROR_WANT_WRITE) { c->ssl_shake_state = comm_ssl_shake_hs_write; comm_point_listen_for_rw(c, 0, 1); return 1; } else if(want == SSL_ERROR_SYSCALL) { #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return 0; /* silence reset by peer */ #endif if(errno != 0) log_err("SSL_read syscall: %s", strerror(errno)); return 0; } log_crypto_err("could not SSL_read"); return 0; } verbose(VERB_ALGO, "ssl http read more skip to %d + %d", (int)sldns_buffer_position(c->buffer), (int)r); sldns_buffer_skip(c->buffer, (ssize_t)r); return 1; #else (void)c; return 0; #endif /* HAVE_SSL */ } /** read more data for http */ static int http_read_more(int fd, struct comm_point* c) { ssize_t r; log_assert(sldns_buffer_remaining(c->buffer) > 0); r = recv(fd, (void*)sldns_buffer_current(c->buffer), sldns_buffer_remaining(c->buffer), 0); if(r == 0) { return 0; } else if(r == -1) { #ifndef USE_WINSOCK if(errno == EINTR || errno == EAGAIN) return 1; #else /* USE_WINSOCK */ if(WSAGetLastError() == WSAECONNRESET) return 0; if(WSAGetLastError() == WSAEINPROGRESS) return 1; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_READ); return 1; } #endif log_err_addr("read (in http r)", sock_strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); return 0; } verbose(VERB_ALGO, "http read more skip to %d + %d", (int)sldns_buffer_position(c->buffer), (int)r); sldns_buffer_skip(c->buffer, r); return 1; } /** return true if http header has been read (one line complete) */ static int http_header_done(sldns_buffer* buf) { size_t i; for(i=sldns_buffer_position(buf); ibuffer); if(!line) return 1; verbose(VERB_ALGO, "http header: %s", line); if(strncasecmp(line, "HTTP/1.1 ", 9) == 0) { /* check returncode */ if(line[9] != '2') { verbose(VERB_ALGO, "http bad status %s", line+9); return 0; } } else if(strncasecmp(line, "Content-Length: ", 16) == 0) { if(!c->http_is_chunked) c->tcp_byte_count = (size_t)atoi(line+16); } else if(strncasecmp(line, "Transfer-Encoding: chunked", 19+7) == 0) { c->tcp_byte_count = 0; c->http_is_chunked = 1; } else if(line[0] == 0) { /* end of initial headers */ c->http_in_headers = 0; if(c->http_is_chunked) c->http_in_chunk_headers = 1; /* remove header text from front of buffer * the buffer is going to be used to return the data segment * itself and we don't want the header to get returned * prepended with it */ http_moveover_buffer(c->buffer); sldns_buffer_flip(c->buffer); return 1; } /* ignore other headers */ return 1; } /** a chunk header is complete, process it, return 0=fail, 1=continue next * header line, 2=done with chunked transfer*/ static int http_process_chunk_header(struct comm_point* c) { char* line = http_header_line(c->buffer); if(!line) return 1; if(c->http_in_chunk_headers == 3) { verbose(VERB_ALGO, "http chunk trailer: %s", line); /* are we done ? */ if(line[0] == 0 && c->tcp_byte_count == 0) { /* callback of http reader when NETEVENT_DONE, * end of data, with no data in buffer */ sldns_buffer_set_position(c->buffer, 0); sldns_buffer_set_limit(c->buffer, 0); fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_DONE, NULL); /* return that we are done */ return 2; } if(line[0] == 0) { /* continue with header of the next chunk */ c->http_in_chunk_headers = 1; /* remove header text from front of buffer */ http_moveover_buffer(c->buffer); sldns_buffer_flip(c->buffer); return 1; } /* ignore further trail headers */ return 1; } verbose(VERB_ALGO, "http chunk header: %s", line); if(c->http_in_chunk_headers == 1) { /* read chunked start line */ char* end = NULL; c->tcp_byte_count = (size_t)strtol(line, &end, 16); if(end == line) return 0; c->http_in_chunk_headers = 0; /* remove header text from front of buffer */ http_moveover_buffer(c->buffer); sldns_buffer_flip(c->buffer); if(c->tcp_byte_count == 0) { /* done with chunks, process chunk_trailer lines */ c->http_in_chunk_headers = 3; } return 1; } /* ignore other headers */ return 1; } /** handle nonchunked data segment, 0=fail, 1=wait */ static int http_nonchunk_segment(struct comm_point* c) { /* c->buffer at position..limit has new data we read in. * the buffer itself is full of nonchunked data. * we are looking to read tcp_byte_count more data * and then the transfer is done. */ size_t remainbufferlen; size_t got_now = sldns_buffer_limit(c->buffer); if(c->tcp_byte_count <= got_now) { /* done, this is the last data fragment */ c->http_stored = 0; sldns_buffer_set_position(c->buffer, 0); fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_DONE, NULL); return 1; } /* if we have the buffer space, * read more data collected into the buffer */ remainbufferlen = sldns_buffer_capacity(c->buffer) - sldns_buffer_limit(c->buffer); if(remainbufferlen+got_now >= c->tcp_byte_count || remainbufferlen >= (size_t)(c->ssl?16384:2048)) { size_t total = sldns_buffer_limit(c->buffer); sldns_buffer_clear(c->buffer); sldns_buffer_set_position(c->buffer, total); c->http_stored = total; /* return and wait to read more */ return 1; } /* call callback with this data amount, then * wait for more */ c->tcp_byte_count -= got_now; c->http_stored = 0; sldns_buffer_set_position(c->buffer, 0); fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_NOERROR, NULL); /* c->callback has to buffer_clear(c->buffer). */ /* return and wait to read more */ return 1; } /** handle chunked data segment, return 0=fail, 1=wait, 2=process more */ static int http_chunked_segment(struct comm_point* c) { /* the c->buffer has from position..limit new data we read. */ /* the current chunk has length tcp_byte_count. * once we read that read more chunk headers. */ size_t remainbufferlen; size_t got_now = sldns_buffer_limit(c->buffer) - c->http_stored; verbose(VERB_ALGO, "http_chunked_segment: got now %d, tcpbytcount %d, http_stored %d, buffer pos %d, buffer limit %d", (int)got_now, (int)c->tcp_byte_count, (int)c->http_stored, (int)sldns_buffer_position(c->buffer), (int)sldns_buffer_limit(c->buffer)); if(c->tcp_byte_count <= got_now) { /* the chunk has completed (with perhaps some extra data * from next chunk header and next chunk) */ /* save too much info into temp buffer */ size_t fraglen; struct comm_reply repinfo; c->http_stored = 0; sldns_buffer_skip(c->buffer, (ssize_t)c->tcp_byte_count); sldns_buffer_clear(c->http_temp); sldns_buffer_write(c->http_temp, sldns_buffer_current(c->buffer), sldns_buffer_remaining(c->buffer)); sldns_buffer_flip(c->http_temp); /* callback with this fragment */ fraglen = sldns_buffer_position(c->buffer); sldns_buffer_set_position(c->buffer, 0); sldns_buffer_set_limit(c->buffer, fraglen); repinfo = c->repinfo; fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_NOERROR, &repinfo); /* c->callback has to buffer_clear(). */ /* is commpoint deleted? */ if(!repinfo.c) { return 1; } /* copy waiting info */ sldns_buffer_clear(c->buffer); sldns_buffer_write(c->buffer, sldns_buffer_begin(c->http_temp), sldns_buffer_remaining(c->http_temp)); sldns_buffer_flip(c->buffer); /* process end of chunk trailer header lines, until * an empty line */ c->http_in_chunk_headers = 3; /* process more data in buffer (if any) */ return 2; } c->tcp_byte_count -= got_now; /* if we have the buffer space, * read more data collected into the buffer */ remainbufferlen = sldns_buffer_capacity(c->buffer) - sldns_buffer_limit(c->buffer); if(remainbufferlen >= c->tcp_byte_count || remainbufferlen >= 2048) { size_t total = sldns_buffer_limit(c->buffer); sldns_buffer_clear(c->buffer); sldns_buffer_set_position(c->buffer, total); c->http_stored = total; /* return and wait to read more */ return 1; } /* callback of http reader for a new part of the data */ c->http_stored = 0; sldns_buffer_set_position(c->buffer, 0); fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_NOERROR, NULL); /* c->callback has to buffer_clear(c->buffer). */ /* return and wait to read more */ return 1; } #ifdef HAVE_NGHTTP2 /** Create new http2 session. Called when creating handling comm point. */ static struct http2_session* http2_session_create(struct comm_point* c) { struct http2_session* session = calloc(1, sizeof(*session)); if(!session) { log_err("malloc failure while creating http2 session"); return NULL; } session->c = c; return session; } #endif /** Delete http2 session. After closing connection or on error */ static void http2_session_delete(struct http2_session* h2_session) { #ifdef HAVE_NGHTTP2 if(h2_session->callbacks) nghttp2_session_callbacks_del(h2_session->callbacks); free(h2_session); #else (void)h2_session; #endif } #ifdef HAVE_NGHTTP2 struct http2_stream* http2_stream_create(int32_t stream_id) { struct http2_stream* h2_stream = calloc(1, sizeof(*h2_stream)); if(!h2_stream) { log_err("malloc failure while creating http2 stream"); return NULL; } h2_stream->stream_id = stream_id; return h2_stream; } /** Delete http2 stream. After session delete or stream close callback */ static void http2_stream_delete(struct http2_session* h2_session, struct http2_stream* h2_stream) { if(h2_stream->mesh_state) { mesh_state_remove_reply(h2_stream->mesh, h2_stream->mesh_state, h2_session->c); h2_stream->mesh_state = NULL; } http2_req_stream_clear(h2_stream); free(h2_stream); } #endif void http2_stream_add_meshstate(struct http2_stream* h2_stream, struct mesh_area* mesh, struct mesh_state* m) { h2_stream->mesh = mesh; h2_stream->mesh_state = m; } /** delete http2 session server. After closing connection. */ static void http2_session_server_delete(struct http2_session* h2_session) { #ifdef HAVE_NGHTTP2 struct http2_stream* h2_stream, *next; nghttp2_session_del(h2_session->session); /* NULL input is fine */ h2_session->session = NULL; for(h2_stream = h2_session->first_stream; h2_stream;) { next = h2_stream->next; http2_stream_delete(h2_session, h2_stream); h2_stream = next; } h2_session->first_stream = NULL; h2_session->is_drop = 0; h2_session->postpone_drop = 0; h2_session->c->h2_stream = NULL; #endif (void)h2_session; } #ifdef HAVE_NGHTTP2 void http2_session_add_stream(struct http2_session* h2_session, struct http2_stream* h2_stream) { if(h2_session->first_stream) h2_session->first_stream->prev = h2_stream; h2_stream->next = h2_session->first_stream; h2_session->first_stream = h2_stream; } /** remove stream from session linked list. After stream close callback or * closing connection */ static void http2_session_remove_stream(struct http2_session* h2_session, struct http2_stream* h2_stream) { if(h2_stream->prev) h2_stream->prev->next = h2_stream->next; else h2_session->first_stream = h2_stream->next; if(h2_stream->next) h2_stream->next->prev = h2_stream->prev; } int http2_stream_close_cb(nghttp2_session* ATTR_UNUSED(session), int32_t stream_id, uint32_t ATTR_UNUSED(error_code), void* cb_arg) { struct http2_stream* h2_stream; struct http2_session* h2_session = (struct http2_session*)cb_arg; if(!(h2_stream = nghttp2_session_get_stream_user_data( h2_session->session, stream_id))) { return 0; } http2_session_remove_stream(h2_session, h2_stream); http2_stream_delete(h2_session, h2_stream); return 0; } ssize_t http2_recv_cb(nghttp2_session* ATTR_UNUSED(session), uint8_t* buf, size_t len, int ATTR_UNUSED(flags), void* cb_arg) { struct http2_session* h2_session = (struct http2_session*)cb_arg; ssize_t ret; log_assert(h2_session->c->type == comm_http); log_assert(h2_session->c->h2_session); #ifdef HAVE_SSL if(h2_session->c->ssl) { int r; ERR_clear_error(); r = SSL_read(h2_session->c->ssl, buf, len); if(r <= 0) { int want = SSL_get_error(h2_session->c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { return NGHTTP2_ERR_EOF; } else if(want == SSL_ERROR_WANT_READ) { return NGHTTP2_ERR_WOULDBLOCK; } else if(want == SSL_ERROR_WANT_WRITE) { h2_session->c->ssl_shake_state = comm_ssl_shake_hs_write; comm_point_listen_for_rw(h2_session->c, 0, 1); return NGHTTP2_ERR_WOULDBLOCK; } else if(want == SSL_ERROR_SYSCALL) { #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return NGHTTP2_ERR_CALLBACK_FAILURE; #endif if(errno != 0) log_err("SSL_read syscall: %s", strerror(errno)); return NGHTTP2_ERR_CALLBACK_FAILURE; } log_crypto_err("could not SSL_read"); return NGHTTP2_ERR_CALLBACK_FAILURE; } return r; } #endif /* HAVE_SSL */ ret = recv(h2_session->c->fd, buf, len, 0); if(ret == 0) { return NGHTTP2_ERR_EOF; } else if(ret < 0) { #ifndef USE_WINSOCK if(errno == EINTR || errno == EAGAIN) return NGHTTP2_ERR_WOULDBLOCK; #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return NGHTTP2_ERR_CALLBACK_FAILURE; #endif log_err_addr("could not http2 recv: %s", strerror(errno), &h2_session->c->repinfo.addr, h2_session->c->repinfo.addrlen); #else /* USE_WINSOCK */ if(WSAGetLastError() == WSAECONNRESET) return NGHTTP2_ERR_CALLBACK_FAILURE; if(WSAGetLastError() == WSAEINPROGRESS) return NGHTTP2_ERR_WOULDBLOCK; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(h2_session->c->ev->ev, UB_EV_READ); return NGHTTP2_ERR_WOULDBLOCK; } log_err_addr("could not http2 recv: %s", wsa_strerror(WSAGetLastError()), &h2_session->c->repinfo.addr, h2_session->c->repinfo.addrlen); #endif return NGHTTP2_ERR_CALLBACK_FAILURE; } return ret; } #endif /* HAVE_NGHTTP2 */ /** Handle http2 read */ static int comm_point_http2_handle_read(int ATTR_UNUSED(fd), struct comm_point* c) { #ifdef HAVE_NGHTTP2 int ret; log_assert(c->h2_session); /* reading until recv cb returns NGHTTP2_ERR_WOULDBLOCK */ ret = nghttp2_session_recv(c->h2_session->session); if(ret) { if(ret != NGHTTP2_ERR_EOF && ret != NGHTTP2_ERR_CALLBACK_FAILURE) { char a[256]; addr_to_str(&c->repinfo.addr, c->repinfo.addrlen, a, sizeof(a)); verbose(VERB_QUERY, "http2: session_recv from %s failed, " "error: %s", a, nghttp2_strerror(ret)); } return 0; } if(nghttp2_session_want_write(c->h2_session->session)) { c->tcp_is_reading = 0; comm_point_stop_listening(c); comm_point_start_listening(c, -1, adjusted_tcp_timeout(c)); } else if(!nghttp2_session_want_read(c->h2_session->session)) return 0; /* connection can be closed */ return 1; #else (void)c; return 0; #endif } /** * Handle http reading callback. * @param fd: file descriptor of socket. * @param c: comm point to read from into buffer. * @return: 0 on error */ static int comm_point_http_handle_read(int fd, struct comm_point* c) { log_assert(c->type == comm_http); log_assert(fd != -1); /* if we are in ssl handshake, handle SSL handshake */ #ifdef HAVE_SSL if(c->ssl && c->ssl_shake_state != comm_ssl_shake_none) { if(!ssl_handshake(c)) return 0; if(c->ssl_shake_state != comm_ssl_shake_none) return 1; } #endif /* HAVE_SSL */ if(!c->tcp_is_reading) return 1; if(c->use_h2) { return comm_point_http2_handle_read(fd, c); } /* http version is <= http/1.1 */ if(c->http_min_version >= http_version_2) { /* HTTP/2 failed, not allowed to use lower version. */ return 0; } /* read more data */ if(c->ssl) { if(!ssl_http_read_more(c)) return 0; } else { if(!http_read_more(fd, c)) return 0; } if(c->http_stored >= sldns_buffer_position(c->buffer)) { /* read did not work but we wanted more data, there is * no bytes to process now. */ return 1; } sldns_buffer_flip(c->buffer); /* if we are partway in a segment of data, position us at the point * where we left off previously */ if(c->http_stored < sldns_buffer_limit(c->buffer)) sldns_buffer_set_position(c->buffer, c->http_stored); else sldns_buffer_set_position(c->buffer, sldns_buffer_limit(c->buffer)); while(sldns_buffer_remaining(c->buffer) > 0) { /* Handle HTTP/1.x data */ /* if we are reading headers, read more headers */ if(c->http_in_headers || c->http_in_chunk_headers) { /* if header is done, process the header */ if(!http_header_done(c->buffer)) { /* copy remaining data to front of buffer * and set rest for writing into it */ http_moveover_buffer(c->buffer); /* return and wait to read more */ return 1; } if(!c->http_in_chunk_headers) { /* process initial headers */ if(!http_process_initial_header(c)) return 0; } else { /* process chunk headers */ int r = http_process_chunk_header(c); if(r == 0) return 0; if(r == 2) return 1; /* done */ /* r == 1, continue */ } /* see if we have more to process */ continue; } if(!c->http_is_chunked) { /* if we are reading nonchunks, process that*/ return http_nonchunk_segment(c); } else { /* if we are reading chunks, read the chunk */ int r = http_chunked_segment(c); if(r == 0) return 0; if(r == 1) return 1; continue; } } /* broke out of the loop; could not process header instead need * to read more */ /* moveover any remaining data and read more data */ http_moveover_buffer(c->buffer); /* return and wait to read more */ return 1; } /** check pending connect for http */ static int http_check_connect(int fd, struct comm_point* c) { /* check for pending error from nonblocking connect */ /* from Stevens, unix network programming, vol1, 3rd ed, p450*/ int error = 0; socklen_t len = (socklen_t)sizeof(error); if(getsockopt(fd, SOL_SOCKET, SO_ERROR, (void*)&error, &len) < 0){ #ifndef USE_WINSOCK error = errno; /* on solaris errno is error */ #else /* USE_WINSOCK */ error = WSAGetLastError(); #endif } #ifndef USE_WINSOCK #if defined(EINPROGRESS) && defined(EWOULDBLOCK) if(error == EINPROGRESS || error == EWOULDBLOCK) return 1; /* try again later */ else #endif if(error != 0 && verbosity < 2) return 0; /* silence lots of chatter in the logs */ else if(error != 0) { log_err_addr("http connect", strerror(error), &c->repinfo.addr, c->repinfo.addrlen); #else /* USE_WINSOCK */ /* examine error */ if(error == WSAEINPROGRESS) return 1; else if(error == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); return 1; } else if(error != 0 && verbosity < 2) return 0; else if(error != 0) { log_err_addr("http connect", wsa_strerror(error), &c->repinfo.addr, c->repinfo.addrlen); #endif /* USE_WINSOCK */ return 0; } /* keep on processing this socket */ return 2; } /** write more data for http (with ssl) */ static int ssl_http_write_more(struct comm_point* c) { #ifdef HAVE_SSL int r; log_assert(sldns_buffer_remaining(c->buffer) > 0); ERR_clear_error(); r = SSL_write(c->ssl, (void*)sldns_buffer_current(c->buffer), (int)sldns_buffer_remaining(c->buffer)); if(r <= 0) { int want = SSL_get_error(c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { return 0; /* closed */ } else if(want == SSL_ERROR_WANT_READ) { c->ssl_shake_state = comm_ssl_shake_hs_read; comm_point_listen_for_rw(c, 1, 0); return 1; /* wait for read condition */ } else if(want == SSL_ERROR_WANT_WRITE) { return 1; /* write more later */ } else if(want == SSL_ERROR_SYSCALL) { #ifdef EPIPE if(errno == EPIPE && verbosity < 2) return 0; /* silence 'broken pipe' */ #endif if(errno != 0) log_err("SSL_write syscall: %s", strerror(errno)); return 0; } log_crypto_err("could not SSL_write"); return 0; } sldns_buffer_skip(c->buffer, (ssize_t)r); return 1; #else (void)c; return 0; #endif /* HAVE_SSL */ } /** write more data for http */ static int http_write_more(int fd, struct comm_point* c) { ssize_t r; log_assert(sldns_buffer_remaining(c->buffer) > 0); r = send(fd, (void*)sldns_buffer_current(c->buffer), sldns_buffer_remaining(c->buffer), 0); if(r == -1) { #ifndef USE_WINSOCK if(errno == EINTR || errno == EAGAIN) return 1; #else if(WSAGetLastError() == WSAEINPROGRESS) return 1; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); return 1; } #endif log_err_addr("http send r", sock_strerror(errno), &c->repinfo.addr, c->repinfo.addrlen); return 0; } sldns_buffer_skip(c->buffer, r); return 1; } #ifdef HAVE_NGHTTP2 ssize_t http2_send_cb(nghttp2_session* ATTR_UNUSED(session), const uint8_t* buf, size_t len, int ATTR_UNUSED(flags), void* cb_arg) { ssize_t ret; struct http2_session* h2_session = (struct http2_session*)cb_arg; log_assert(h2_session->c->type == comm_http); log_assert(h2_session->c->h2_session); #ifdef HAVE_SSL if(h2_session->c->ssl) { int r; ERR_clear_error(); r = SSL_write(h2_session->c->ssl, buf, len); if(r <= 0) { int want = SSL_get_error(h2_session->c->ssl, r); if(want == SSL_ERROR_ZERO_RETURN) { return NGHTTP2_ERR_CALLBACK_FAILURE; } else if(want == SSL_ERROR_WANT_READ) { h2_session->c->ssl_shake_state = comm_ssl_shake_hs_read; comm_point_listen_for_rw(h2_session->c, 1, 0); return NGHTTP2_ERR_WOULDBLOCK; } else if(want == SSL_ERROR_WANT_WRITE) { return NGHTTP2_ERR_WOULDBLOCK; } else if(want == SSL_ERROR_SYSCALL) { #ifdef EPIPE if(errno == EPIPE && verbosity < 2) return NGHTTP2_ERR_CALLBACK_FAILURE; #endif if(errno != 0) log_err("SSL_write syscall: %s", strerror(errno)); return NGHTTP2_ERR_CALLBACK_FAILURE; } log_crypto_err("could not SSL_write"); return NGHTTP2_ERR_CALLBACK_FAILURE; } return r; } #endif /* HAVE_SSL */ ret = send(h2_session->c->fd, buf, len, 0); if(ret == 0) { return NGHTTP2_ERR_CALLBACK_FAILURE; } else if(ret < 0) { #ifndef USE_WINSOCK if(errno == EINTR || errno == EAGAIN) return NGHTTP2_ERR_WOULDBLOCK; #ifdef EPIPE if(errno == EPIPE && verbosity < 2) return NGHTTP2_ERR_CALLBACK_FAILURE; #endif #ifdef ECONNRESET if(errno == ECONNRESET && verbosity < 2) return NGHTTP2_ERR_CALLBACK_FAILURE; #endif log_err_addr("could not http2 write: %s", strerror(errno), &h2_session->c->repinfo.addr, h2_session->c->repinfo.addrlen); #else /* USE_WINSOCK */ if(WSAGetLastError() == WSAENOTCONN) return NGHTTP2_ERR_WOULDBLOCK; if(WSAGetLastError() == WSAEINPROGRESS) return NGHTTP2_ERR_WOULDBLOCK; if(WSAGetLastError() == WSAEWOULDBLOCK) { ub_winsock_tcp_wouldblock(h2_session->c->ev->ev, UB_EV_WRITE); return NGHTTP2_ERR_WOULDBLOCK; } if(WSAGetLastError() == WSAECONNRESET && verbosity < 2) return NGHTTP2_ERR_CALLBACK_FAILURE; log_err_addr("could not http2 write: %s", wsa_strerror(WSAGetLastError()), &h2_session->c->repinfo.addr, h2_session->c->repinfo.addrlen); #endif return NGHTTP2_ERR_CALLBACK_FAILURE; } return ret; } #endif /* HAVE_NGHTTP2 */ /** Handle http2 writing */ static int comm_point_http2_handle_write(int ATTR_UNUSED(fd), struct comm_point* c) { #ifdef HAVE_NGHTTP2 int ret; log_assert(c->h2_session); ret = nghttp2_session_send(c->h2_session->session); if(ret) { verbose(VERB_QUERY, "http2: session_send failed, " "error: %s", nghttp2_strerror(ret)); return 0; } if(nghttp2_session_want_read(c->h2_session->session)) { c->tcp_is_reading = 1; comm_point_stop_listening(c); comm_point_start_listening(c, -1, adjusted_tcp_timeout(c)); } else if(!nghttp2_session_want_write(c->h2_session->session)) return 0; /* connection can be closed */ return 1; #else (void)c; return 0; #endif } /** * Handle http writing callback. * @param fd: file descriptor of socket. * @param c: comm point to write buffer out of. * @return: 0 on error */ static int comm_point_http_handle_write(int fd, struct comm_point* c) { log_assert(c->type == comm_http); log_assert(fd != -1); /* check pending connect errors, if that fails, we wait for more, * or we can continue to write contents */ if(c->tcp_check_nb_connect) { int r = http_check_connect(fd, c); if(r == 0) return 0; if(r == 1) return 1; c->tcp_check_nb_connect = 0; } /* if we are in ssl handshake, handle SSL handshake */ #ifdef HAVE_SSL if(c->ssl && c->ssl_shake_state != comm_ssl_shake_none) { if(!ssl_handshake(c)) return 0; if(c->ssl_shake_state != comm_ssl_shake_none) return 1; } #endif /* HAVE_SSL */ if(c->tcp_is_reading) return 1; if(c->use_h2) { return comm_point_http2_handle_write(fd, c); } /* http version is <= http/1.1 */ if(c->http_min_version >= http_version_2) { /* HTTP/2 failed, not allowed to use lower version. */ return 0; } /* if we are writing, write more */ if(c->ssl) { if(!ssl_http_write_more(c)) return 0; } else { if(!http_write_more(fd, c)) return 0; } /* we write a single buffer contents, that can contain * the http request, and then flip to read the results */ /* see if write is done */ if(sldns_buffer_remaining(c->buffer) == 0) { sldns_buffer_clear(c->buffer); if(c->tcp_do_toggle_rw) c->tcp_is_reading = 1; c->tcp_byte_count = 0; /* switch from listening(write) to listening(read) */ comm_point_stop_listening(c); comm_point_start_listening(c, -1, -1); } return 1; } void comm_point_http_handle_callback(int fd, short event, void* arg) { struct comm_point* c = (struct comm_point*)arg; log_assert(c->type == comm_http); ub_comm_base_now(c->ev->base); if(event&UB_EV_TIMEOUT) { verbose(VERB_QUERY, "http took too long, dropped"); reclaim_http_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_TIMEOUT, NULL); } return; } if(event&UB_EV_READ) { if(!comm_point_http_handle_read(fd, c)) { reclaim_http_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } } return; } if(event&UB_EV_WRITE) { if(!comm_point_http_handle_write(fd, c)) { reclaim_http_handler(c); if(!c->tcp_do_close) { fptr_ok(fptr_whitelist_comm_point( c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } } return; } log_err("Ignored event %d for httphdl.", event); } void comm_point_local_handle_callback(int fd, short event, void* arg) { struct comm_point* c = (struct comm_point*)arg; log_assert(c->type == comm_local); ub_comm_base_now(c->ev->base); if(event&UB_EV_READ) { if(!comm_point_tcp_handle_read(fd, c, 1)) { fptr_ok(fptr_whitelist_comm_point(c->callback)); (void)(*c->callback)(c, c->cb_arg, NETEVENT_CLOSED, NULL); } return; } log_err("Ignored event %d for localhdl.", event); } void comm_point_raw_handle_callback(int ATTR_UNUSED(fd), short event, void* arg) { struct comm_point* c = (struct comm_point*)arg; int err = NETEVENT_NOERROR; log_assert(c->type == comm_raw); ub_comm_base_now(c->ev->base); if(event&UB_EV_TIMEOUT) err = NETEVENT_TIMEOUT; fptr_ok(fptr_whitelist_comm_point_raw(c->callback)); (void)(*c->callback)(c, c->cb_arg, err, NULL); } struct comm_point* comm_point_create_udp(struct comm_base *base, int fd, sldns_buffer* buffer, comm_point_callback_type* callback, void* callback_arg, struct unbound_socket* socket) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = fd; c->buffer = buffer; c->timeout = NULL; c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_parent = NULL; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_udp; c->tcp_do_close = 0; c->do_not_close = 0; c->tcp_do_toggle_rw = 0; c->tcp_check_nb_connect = 0; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 0; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = buffer; #endif c->inuse = 0; c->callback = callback; c->cb_arg = callback_arg; c->socket = socket; evbits = UB_EV_READ | UB_EV_PERSIST; /* ub_event stuff */ c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_udp_callback, c); if(c->ev->ev == NULL) { log_err("could not baseset udp event"); comm_point_delete(c); return NULL; } if(fd!=-1 && ub_event_add(c->ev->ev, c->timeout) != 0 ) { log_err("could not add udp event"); comm_point_delete(c); return NULL; } c->event_added = 1; return c; } struct comm_point* comm_point_create_udp_ancil(struct comm_base *base, int fd, sldns_buffer* buffer, comm_point_callback_type* callback, void* callback_arg, struct unbound_socket* socket) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = fd; c->buffer = buffer; c->timeout = NULL; c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_parent = NULL; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_udp; c->tcp_do_close = 0; c->do_not_close = 0; #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = buffer; #endif c->inuse = 0; c->tcp_do_toggle_rw = 0; c->tcp_check_nb_connect = 0; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 0; #endif c->callback = callback; c->cb_arg = callback_arg; c->socket = socket; evbits = UB_EV_READ | UB_EV_PERSIST; /* ub_event stuff */ c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_udp_ancil_callback, c); if(c->ev->ev == NULL) { log_err("could not baseset udp event"); comm_point_delete(c); return NULL; } if(fd!=-1 && ub_event_add(c->ev->ev, c->timeout) != 0 ) { log_err("could not add udp event"); comm_point_delete(c); return NULL; } c->event_added = 1; return c; } static struct comm_point* comm_point_create_tcp_handler(struct comm_base *base, struct comm_point* parent, size_t bufsize, struct sldns_buffer* spoolbuf, comm_point_callback_type* callback, void* callback_arg, struct unbound_socket* socket) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = -1; c->buffer = sldns_buffer_new(bufsize); if(!c->buffer) { free(c->ev); free(c); return NULL; } c->timeout = (struct timeval*)malloc(sizeof(struct timeval)); if(!c->timeout) { sldns_buffer_free(c->buffer); free(c->ev); free(c); return NULL; } c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_parent = parent; c->tcp_timeout_msec = parent->tcp_timeout_msec; c->tcp_conn_limit = parent->tcp_conn_limit; c->tcl_addr = NULL; c->tcp_keepalive = 0; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_tcp; c->tcp_do_close = 0; c->do_not_close = 0; c->tcp_do_toggle_rw = 1; c->tcp_check_nb_connect = 0; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 0; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; /* We don't know just yet if this is a dnscrypt channel. Allocation * will be done when handling the callback. */ c->dnscrypt_buffer = c->buffer; #endif c->repinfo.c = c; c->callback = callback; c->cb_arg = callback_arg; c->socket = socket; if(spoolbuf) { c->tcp_req_info = tcp_req_info_create(spoolbuf); if(!c->tcp_req_info) { log_err("could not create tcp commpoint"); sldns_buffer_free(c->buffer); free(c->timeout); free(c->ev); free(c); return NULL; } c->tcp_req_info->cp = c; c->tcp_do_close = 1; c->tcp_do_toggle_rw = 0; } /* add to parent free list */ c->tcp_free = parent->tcp_free; parent->tcp_free = c; /* ub_event stuff */ evbits = UB_EV_PERSIST | UB_EV_READ | UB_EV_TIMEOUT; c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_tcp_handle_callback, c); if(c->ev->ev == NULL) { log_err("could not basetset tcphdl event"); parent->tcp_free = c->tcp_free; tcp_req_info_delete(c->tcp_req_info); sldns_buffer_free(c->buffer); free(c->timeout); free(c->ev); free(c); return NULL; } return c; } static struct comm_point* comm_point_create_http_handler(struct comm_base *base, struct comm_point* parent, size_t bufsize, int harden_large_queries, uint32_t http_max_streams, char* http_endpoint, comm_point_callback_type* callback, void* callback_arg, struct unbound_socket* socket) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = -1; c->buffer = sldns_buffer_new(bufsize); if(!c->buffer) { free(c->ev); free(c); return NULL; } c->timeout = (struct timeval*)malloc(sizeof(struct timeval)); if(!c->timeout) { sldns_buffer_free(c->buffer); free(c->ev); free(c); return NULL; } c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_parent = parent; c->tcp_timeout_msec = parent->tcp_timeout_msec; c->tcp_conn_limit = parent->tcp_conn_limit; c->tcl_addr = NULL; c->tcp_keepalive = 0; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_http; c->tcp_do_close = 1; c->do_not_close = 0; c->tcp_do_toggle_rw = 1; /* will be set to 0 after http2 upgrade */ c->tcp_check_nb_connect = 0; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 0; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = NULL; #endif c->repinfo.c = c; c->callback = callback; c->cb_arg = callback_arg; c->socket = socket; c->http_min_version = http_version_2; c->http2_stream_max_qbuffer_size = bufsize; if(harden_large_queries && bufsize > 512) c->http2_stream_max_qbuffer_size = 512; c->http2_max_streams = http_max_streams; if(!(c->http_endpoint = strdup(http_endpoint))) { log_err("could not strdup http_endpoint"); sldns_buffer_free(c->buffer); free(c->timeout); free(c->ev); free(c); return NULL; } c->use_h2 = 0; #ifdef HAVE_NGHTTP2 if(!(c->h2_session = http2_session_create(c))) { log_err("could not create http2 session"); free(c->http_endpoint); sldns_buffer_free(c->buffer); free(c->timeout); free(c->ev); free(c); return NULL; } if(!(c->h2_session->callbacks = http2_req_callbacks_create())) { log_err("could not create http2 callbacks"); http2_session_delete(c->h2_session); free(c->http_endpoint); sldns_buffer_free(c->buffer); free(c->timeout); free(c->ev); free(c); return NULL; } #endif /* add to parent free list */ c->tcp_free = parent->tcp_free; parent->tcp_free = c; /* ub_event stuff */ evbits = UB_EV_PERSIST | UB_EV_READ | UB_EV_TIMEOUT; c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_http_handle_callback, c); if(c->ev->ev == NULL) { log_err("could not set http handler event"); parent->tcp_free = c->tcp_free; http2_session_delete(c->h2_session); sldns_buffer_free(c->buffer); free(c->timeout); free(c->ev); free(c); return NULL; } return c; } struct comm_point* comm_point_create_tcp(struct comm_base *base, int fd, int num, int idle_timeout, int harden_large_queries, uint32_t http_max_streams, char* http_endpoint, struct tcl_list* tcp_conn_limit, size_t bufsize, struct sldns_buffer* spoolbuf, enum listen_type port_type, comm_point_callback_type* callback, void* callback_arg, struct unbound_socket* socket) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; int i; /* first allocate the TCP accept listener */ if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = fd; c->buffer = NULL; c->timeout = NULL; c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_timeout_msec = idle_timeout; c->tcp_conn_limit = tcp_conn_limit; c->tcl_addr = NULL; c->tcp_keepalive = 0; c->tcp_parent = NULL; c->max_tcp_count = num; c->cur_tcp_count = 0; c->tcp_handlers = (struct comm_point**)calloc((size_t)num, sizeof(struct comm_point*)); if(!c->tcp_handlers) { free(c->ev); free(c); return NULL; } c->tcp_free = NULL; c->type = comm_tcp_accept; c->tcp_do_close = 0; c->do_not_close = 0; c->tcp_do_toggle_rw = 0; c->tcp_check_nb_connect = 0; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 0; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = NULL; #endif c->callback = NULL; c->cb_arg = NULL; c->socket = socket; evbits = UB_EV_READ | UB_EV_PERSIST; /* ub_event stuff */ c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_tcp_accept_callback, c); if(c->ev->ev == NULL) { log_err("could not baseset tcpacc event"); comm_point_delete(c); return NULL; } if (ub_event_add(c->ev->ev, c->timeout) != 0) { log_err("could not add tcpacc event"); comm_point_delete(c); return NULL; } c->event_added = 1; /* now prealloc the handlers */ for(i=0; itcp_handlers[i] = comm_point_create_tcp_handler(base, c, bufsize, spoolbuf, callback, callback_arg, socket); } else if(port_type == listen_type_http) { c->tcp_handlers[i] = comm_point_create_http_handler( base, c, bufsize, harden_large_queries, http_max_streams, http_endpoint, callback, callback_arg, socket); } else { log_err("could not create tcp handler, unknown listen " "type"); return NULL; } if(!c->tcp_handlers[i]) { comm_point_delete(c); return NULL; } } return c; } struct comm_point* comm_point_create_tcp_out(struct comm_base *base, size_t bufsize, comm_point_callback_type* callback, void* callback_arg) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = -1; c->buffer = sldns_buffer_new(bufsize); if(!c->buffer) { free(c->ev); free(c); return NULL; } c->timeout = NULL; c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_timeout_msec = TCP_QUERY_TIMEOUT; c->tcp_conn_limit = NULL; c->tcl_addr = NULL; c->tcp_keepalive = 0; c->tcp_parent = NULL; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_tcp; c->tcp_do_close = 0; c->do_not_close = 0; c->tcp_do_toggle_rw = 1; c->tcp_check_nb_connect = 1; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 1; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = c->buffer; #endif c->repinfo.c = c; c->callback = callback; c->cb_arg = callback_arg; evbits = UB_EV_PERSIST | UB_EV_WRITE; c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_tcp_handle_callback, c); if(c->ev->ev == NULL) { log_err("could not baseset tcpout event"); sldns_buffer_free(c->buffer); free(c->ev); free(c); return NULL; } return c; } struct comm_point* comm_point_create_http_out(struct comm_base *base, size_t bufsize, comm_point_callback_type* callback, void* callback_arg, sldns_buffer* temp) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = -1; c->buffer = sldns_buffer_new(bufsize); if(!c->buffer) { free(c->ev); free(c); return NULL; } c->timeout = NULL; c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_parent = NULL; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_http; c->tcp_do_close = 0; c->do_not_close = 0; c->tcp_do_toggle_rw = 1; c->tcp_check_nb_connect = 1; c->http_in_headers = 1; c->http_in_chunk_headers = 0; c->http_is_chunked = 0; c->http_temp = temp; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 1; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = c->buffer; #endif c->repinfo.c = c; c->callback = callback; c->cb_arg = callback_arg; evbits = UB_EV_PERSIST | UB_EV_WRITE; c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_http_handle_callback, c); if(c->ev->ev == NULL) { log_err("could not baseset tcpout event"); #ifdef HAVE_SSL SSL_free(c->ssl); #endif sldns_buffer_free(c->buffer); free(c->ev); free(c); return NULL; } return c; } struct comm_point* comm_point_create_local(struct comm_base *base, int fd, size_t bufsize, comm_point_callback_type* callback, void* callback_arg) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = fd; c->buffer = sldns_buffer_new(bufsize); if(!c->buffer) { free(c->ev); free(c); return NULL; } c->timeout = NULL; c->tcp_is_reading = 1; c->tcp_byte_count = 0; c->tcp_parent = NULL; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_local; c->tcp_do_close = 0; c->do_not_close = 1; c->tcp_do_toggle_rw = 0; c->tcp_check_nb_connect = 0; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 0; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = c->buffer; #endif c->callback = callback; c->cb_arg = callback_arg; /* ub_event stuff */ evbits = UB_EV_PERSIST | UB_EV_READ; c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_local_handle_callback, c); if(c->ev->ev == NULL) { log_err("could not baseset localhdl event"); free(c->ev); free(c); return NULL; } if (ub_event_add(c->ev->ev, c->timeout) != 0) { log_err("could not add localhdl event"); ub_event_free(c->ev->ev); free(c->ev); free(c); return NULL; } c->event_added = 1; return c; } struct comm_point* comm_point_create_raw(struct comm_base* base, int fd, int writing, comm_point_callback_type* callback, void* callback_arg) { struct comm_point* c = (struct comm_point*)calloc(1, sizeof(struct comm_point)); short evbits; if(!c) return NULL; c->ev = (struct internal_event*)calloc(1, sizeof(struct internal_event)); if(!c->ev) { free(c); return NULL; } c->ev->base = base; c->fd = fd; c->buffer = NULL; c->timeout = NULL; c->tcp_is_reading = 0; c->tcp_byte_count = 0; c->tcp_parent = NULL; c->max_tcp_count = 0; c->cur_tcp_count = 0; c->tcp_handlers = NULL; c->tcp_free = NULL; c->type = comm_raw; c->tcp_do_close = 0; c->do_not_close = 1; c->tcp_do_toggle_rw = 0; c->tcp_check_nb_connect = 0; #ifdef USE_MSG_FASTOPEN c->tcp_do_fastopen = 0; #endif #ifdef USE_DNSCRYPT c->dnscrypt = 0; c->dnscrypt_buffer = c->buffer; #endif c->callback = callback; c->cb_arg = callback_arg; /* ub_event stuff */ if(writing) evbits = UB_EV_PERSIST | UB_EV_WRITE; else evbits = UB_EV_PERSIST | UB_EV_READ; c->ev->ev = ub_event_new(base->eb->base, c->fd, evbits, comm_point_raw_handle_callback, c); if(c->ev->ev == NULL) { log_err("could not baseset rawhdl event"); free(c->ev); free(c); return NULL; } if (ub_event_add(c->ev->ev, c->timeout) != 0) { log_err("could not add rawhdl event"); ub_event_free(c->ev->ev); free(c->ev); free(c); return NULL; } c->event_added = 1; return c; } void comm_point_close(struct comm_point* c) { if(!c) return; if(c->fd != -1) { verbose(5, "comm_point_close of %d: event_del", c->fd); if(c->event_added) { if(ub_event_del(c->ev->ev) != 0) { log_err("could not event_del on close"); } c->event_added = 0; } } tcl_close_connection(c->tcl_addr); if(c->tcp_req_info) tcp_req_info_clear(c->tcp_req_info); if(c->h2_session) http2_session_server_delete(c->h2_session); /* close fd after removing from event lists, or epoll.. is messed up */ if(c->fd != -1 && !c->do_not_close) { #ifdef USE_WINSOCK if(c->type == comm_tcp || c->type == comm_http) { /* delete sticky events for the fd, it gets closed */ ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_READ); ub_winsock_tcp_wouldblock(c->ev->ev, UB_EV_WRITE); } #endif verbose(VERB_ALGO, "close fd %d", c->fd); sock_close(c->fd); } c->fd = -1; } void comm_point_delete(struct comm_point* c) { if(!c) return; if((c->type == comm_tcp || c->type == comm_http) && c->ssl) { #ifdef HAVE_SSL SSL_shutdown(c->ssl); SSL_free(c->ssl); #endif } if(c->type == comm_http && c->http_endpoint) { free(c->http_endpoint); c->http_endpoint = NULL; } comm_point_close(c); if(c->tcp_handlers) { int i; for(i=0; imax_tcp_count; i++) comm_point_delete(c->tcp_handlers[i]); free(c->tcp_handlers); } free(c->timeout); if(c->type == comm_tcp || c->type == comm_local || c->type == comm_http) { sldns_buffer_free(c->buffer); #ifdef USE_DNSCRYPT if(c->dnscrypt && c->dnscrypt_buffer != c->buffer) { sldns_buffer_free(c->dnscrypt_buffer); } #endif if(c->tcp_req_info) { tcp_req_info_delete(c->tcp_req_info); } if(c->h2_session) { http2_session_delete(c->h2_session); } } ub_event_free(c->ev->ev); free(c->ev); free(c); } void comm_point_send_reply(struct comm_reply *repinfo) { struct sldns_buffer* buffer; log_assert(repinfo && repinfo->c); #ifdef USE_DNSCRYPT buffer = repinfo->c->dnscrypt_buffer; if(!dnsc_handle_uncurved_request(repinfo)) { return; } #else buffer = repinfo->c->buffer; #endif if(repinfo->c->type == comm_udp) { if(repinfo->srctype) comm_point_send_udp_msg_if(repinfo->c, buffer, (struct sockaddr*)&repinfo->addr, repinfo->addrlen, repinfo); else comm_point_send_udp_msg(repinfo->c, buffer, (struct sockaddr*)&repinfo->addr, repinfo->addrlen, 0); #ifdef USE_DNSTAP /* * sending src (client)/dst (local service) addresses over DNSTAP from udp callback */ if(repinfo->c->dtenv != NULL && repinfo->c->dtenv->log_client_response_messages) { log_addr(VERB_ALGO, "from local addr", (void*)repinfo->c->socket->addr->ai_addr, repinfo->c->socket->addr->ai_addrlen); log_addr(VERB_ALGO, "response to client", &repinfo->addr, repinfo->addrlen); dt_msg_send_client_response(repinfo->c->dtenv, &repinfo->addr, (void*)repinfo->c->socket->addr->ai_addr, repinfo->c->type, repinfo->c->buffer); } #endif } else { #ifdef USE_DNSTAP /* * sending src (client)/dst (local service) addresses over DNSTAP from TCP callback */ if(repinfo->c->tcp_parent->dtenv != NULL && repinfo->c->tcp_parent->dtenv->log_client_response_messages) { log_addr(VERB_ALGO, "from local addr", (void*)repinfo->c->socket->addr->ai_addr, repinfo->c->socket->addr->ai_addrlen); log_addr(VERB_ALGO, "response to client", &repinfo->addr, repinfo->addrlen); dt_msg_send_client_response(repinfo->c->tcp_parent->dtenv, &repinfo->addr, (void*)repinfo->c->socket->addr->ai_addr, repinfo->c->type, ( repinfo->c->tcp_req_info? repinfo->c->tcp_req_info->spool_buffer: repinfo->c->buffer )); } #endif if(repinfo->c->tcp_req_info) { tcp_req_info_send_reply(repinfo->c->tcp_req_info); } else if(repinfo->c->use_h2) { if(!http2_submit_dns_response(repinfo->c->h2_session)) { comm_point_drop_reply(repinfo); return; } repinfo->c->h2_stream = NULL; repinfo->c->tcp_is_reading = 0; comm_point_stop_listening(repinfo->c); comm_point_start_listening(repinfo->c, -1, adjusted_tcp_timeout(repinfo->c)); return; } else { comm_point_start_listening(repinfo->c, -1, adjusted_tcp_timeout(repinfo->c)); } } } void comm_point_drop_reply(struct comm_reply* repinfo) { if(!repinfo) return; log_assert(repinfo->c); log_assert(repinfo->c->type != comm_tcp_accept); if(repinfo->c->type == comm_udp) return; if(repinfo->c->tcp_req_info) repinfo->c->tcp_req_info->is_drop = 1; if(repinfo->c->type == comm_http) { if(repinfo->c->h2_session) { repinfo->c->h2_session->is_drop = 1; if(!repinfo->c->h2_session->postpone_drop) reclaim_http_handler(repinfo->c); return; } reclaim_http_handler(repinfo->c); return; } reclaim_tcp_handler(repinfo->c); } void comm_point_stop_listening(struct comm_point* c) { verbose(VERB_ALGO, "comm point stop listening %d", c->fd); if(c->event_added) { if(ub_event_del(c->ev->ev) != 0) { log_err("event_del error to stoplisten"); } c->event_added = 0; } } void comm_point_start_listening(struct comm_point* c, int newfd, int msec) { verbose(VERB_ALGO, "comm point start listening %d (%d msec)", c->fd==-1?newfd:c->fd, msec); if(c->type == comm_tcp_accept && !c->tcp_free) { /* no use to start listening no free slots. */ return; } if(c->event_added) { if(ub_event_del(c->ev->ev) != 0) { log_err("event_del error to startlisten"); } c->event_added = 0; } if(msec != -1 && msec != 0) { if(!c->timeout) { c->timeout = (struct timeval*)malloc(sizeof( struct timeval)); if(!c->timeout) { log_err("cpsl: malloc failed. No net read."); return; } } ub_event_add_bits(c->ev->ev, UB_EV_TIMEOUT); #ifndef S_SPLINT_S /* splint fails on struct timeval. */ c->timeout->tv_sec = msec/1000; c->timeout->tv_usec = (msec%1000)*1000; #endif /* S_SPLINT_S */ } else { if(msec == 0 || !c->timeout) { ub_event_del_bits(c->ev->ev, UB_EV_TIMEOUT); } } if(c->type == comm_tcp || c->type == comm_http) { ub_event_del_bits(c->ev->ev, UB_EV_READ|UB_EV_WRITE); if(c->tcp_write_and_read) { verbose(5, "startlistening %d mode rw", (newfd==-1?c->fd:newfd)); ub_event_add_bits(c->ev->ev, UB_EV_READ|UB_EV_WRITE); } else if(c->tcp_is_reading) { verbose(5, "startlistening %d mode r", (newfd==-1?c->fd:newfd)); ub_event_add_bits(c->ev->ev, UB_EV_READ); } else { verbose(5, "startlistening %d mode w", (newfd==-1?c->fd:newfd)); ub_event_add_bits(c->ev->ev, UB_EV_WRITE); } } if(newfd != -1) { if(c->fd != -1 && c->fd != newfd) { verbose(5, "cpsl close of fd %d for %d", c->fd, newfd); sock_close(c->fd); } c->fd = newfd; ub_event_set_fd(c->ev->ev, c->fd); } if(ub_event_add(c->ev->ev, msec==0?NULL:c->timeout) != 0) { log_err("event_add failed. in cpsl."); return; } c->event_added = 1; } void comm_point_listen_for_rw(struct comm_point* c, int rd, int wr) { verbose(VERB_ALGO, "comm point listen_for_rw %d %d", c->fd, wr); if(c->event_added) { if(ub_event_del(c->ev->ev) != 0) { log_err("event_del error to cplf"); } c->event_added = 0; } if(!c->timeout) { ub_event_del_bits(c->ev->ev, UB_EV_TIMEOUT); } ub_event_del_bits(c->ev->ev, UB_EV_READ|UB_EV_WRITE); if(rd) ub_event_add_bits(c->ev->ev, UB_EV_READ); if(wr) ub_event_add_bits(c->ev->ev, UB_EV_WRITE); if(ub_event_add(c->ev->ev, c->timeout) != 0) { log_err("event_add failed. in cplf."); return; } c->event_added = 1; } size_t comm_point_get_mem(struct comm_point* c) { size_t s; if(!c) return 0; s = sizeof(*c) + sizeof(*c->ev); if(c->timeout) s += sizeof(*c->timeout); if(c->type == comm_tcp || c->type == comm_local) { s += sizeof(*c->buffer) + sldns_buffer_capacity(c->buffer); #ifdef USE_DNSCRYPT s += sizeof(*c->dnscrypt_buffer); if(c->buffer != c->dnscrypt_buffer) { s += sldns_buffer_capacity(c->dnscrypt_buffer); } #endif } if(c->type == comm_tcp_accept) { int i; for(i=0; imax_tcp_count; i++) s += comm_point_get_mem(c->tcp_handlers[i]); } return s; } struct comm_timer* comm_timer_create(struct comm_base* base, void (*cb)(void*), void* cb_arg) { struct internal_timer *tm = (struct internal_timer*)calloc(1, sizeof(struct internal_timer)); if(!tm) { log_err("malloc failed"); return NULL; } tm->super.ev_timer = tm; tm->base = base; tm->super.callback = cb; tm->super.cb_arg = cb_arg; tm->ev = ub_event_new(base->eb->base, -1, UB_EV_TIMEOUT, comm_timer_callback, &tm->super); if(tm->ev == NULL) { log_err("timer_create: event_base_set failed."); free(tm); return NULL; } return &tm->super; } void comm_timer_disable(struct comm_timer* timer) { if(!timer) return; ub_timer_del(timer->ev_timer->ev); timer->ev_timer->enabled = 0; } void comm_timer_set(struct comm_timer* timer, struct timeval* tv) { log_assert(tv); if(timer->ev_timer->enabled) comm_timer_disable(timer); if(ub_timer_add(timer->ev_timer->ev, timer->ev_timer->base->eb->base, comm_timer_callback, timer, tv) != 0) log_err("comm_timer_set: evtimer_add failed."); timer->ev_timer->enabled = 1; } void comm_timer_delete(struct comm_timer* timer) { if(!timer) return; comm_timer_disable(timer); /* Free the sub struct timer->ev_timer derived from the super struct timer. * i.e. assert(timer == timer->ev_timer) */ ub_event_free(timer->ev_timer->ev); free(timer->ev_timer); } void comm_timer_callback(int ATTR_UNUSED(fd), short event, void* arg) { struct comm_timer* tm = (struct comm_timer*)arg; if(!(event&UB_EV_TIMEOUT)) return; ub_comm_base_now(tm->ev_timer->base); tm->ev_timer->enabled = 0; fptr_ok(fptr_whitelist_comm_timer(tm->callback)); (*tm->callback)(tm->cb_arg); } int comm_timer_is_set(struct comm_timer* timer) { return (int)timer->ev_timer->enabled; } size_t comm_timer_get_mem(struct comm_timer* ATTR_UNUSED(timer)) { return sizeof(struct internal_timer); } struct comm_signal* comm_signal_create(struct comm_base* base, void (*callback)(int, void*), void* cb_arg) { struct comm_signal* com = (struct comm_signal*)malloc( sizeof(struct comm_signal)); if(!com) { log_err("malloc failed"); return NULL; } com->base = base; com->callback = callback; com->cb_arg = cb_arg; com->ev_signal = NULL; return com; } void comm_signal_callback(int sig, short event, void* arg) { struct comm_signal* comsig = (struct comm_signal*)arg; if(!(event & UB_EV_SIGNAL)) return; ub_comm_base_now(comsig->base); fptr_ok(fptr_whitelist_comm_signal(comsig->callback)); (*comsig->callback)(sig, comsig->cb_arg); } int comm_signal_bind(struct comm_signal* comsig, int sig) { struct internal_signal* entry = (struct internal_signal*)calloc(1, sizeof(struct internal_signal)); if(!entry) { log_err("malloc failed"); return 0; } log_assert(comsig); /* add signal event */ entry->ev = ub_signal_new(comsig->base->eb->base, sig, comm_signal_callback, comsig); if(entry->ev == NULL) { log_err("Could not create signal event"); free(entry); return 0; } if(ub_signal_add(entry->ev, NULL) != 0) { log_err("Could not add signal handler"); ub_event_free(entry->ev); free(entry); return 0; } /* link into list */ entry->next = comsig->ev_signal; comsig->ev_signal = entry; return 1; } void comm_signal_delete(struct comm_signal* comsig) { struct internal_signal* p, *np; if(!comsig) return; p=comsig->ev_signal; while(p) { np = p->next; ub_signal_del(p->ev); ub_event_free(p->ev); free(p); p = np; } free(comsig); }