/*************************************************************************** * nsock_core.c -- This contains the core engine routines for the nsock * * parallel socket event library. * * * ***********************IMPORTANT NSOCK LICENSE TERMS*********************** * * * The nsock parallel socket event library is (C) 1999-2009 Insecure.Com * * LLC This library is free software; you may redistribute and/or * * modify it under the terms of the GNU General Public License as * * published by the Free Software Foundation; Version 2. This guarantees * * your right to use, modify, and redistribute this software under certain * * conditions. If this license is unacceptable to you, Insecure.Com LLC * * may be willing to sell alternative licenses (contact * * sales@insecure.com ). * * * * As a special exception to the GPL terms, Insecure.Com LLC grants * * permission to link the code of this program with any version of the * * OpenSSL library which is distributed under a license identical to that * * listed in the included COPYING.OpenSSL file, and distribute linked * * combinations including the two. You must obey the GNU GPL in all * * respects for all of the code used other than OpenSSL. If you modify * * this file, you may extend this exception to your version of the file, * * but you are not obligated to do so. * * * * If you received these files with a written license agreement stating * * terms other than the (GPL) terms above, then that alternative license * * agreement takes precedence over this comment. * * * * Source is provided to this software because we believe users have a * * right to know exactly what a program is going to do before they run it. * * This also allows you to audit the software for security holes (none * * have been found so far). * * * * Source code also allows you to port Nmap to new platforms, fix bugs, * * and add new features. You are highly encouraged to send your changes * * to nmap-dev@insecure.org for possible incorporation into the main * * distribution. By sending these changes to Fyodor or one of the * * Insecure.Org development mailing lists, it is assumed that you are * * offering the Nmap Project (Insecure.Com LLC) the unlimited, * * non-exclusive right to reuse, modify, and relicense the code. Nmap * * will always be available Open Source, but this is important because the * * inability to relicense code has caused devastating problems for other * * Free Software projects (such as KDE and NASM). We also occasionally * * relicense the code to third parties as discussed above. If you wish to * * specify special license conditions of your contributions, just say so * * when you send them. * * * * This program is distributed in the hope that it will be useful, but * * WITHOUT ANY WARRANTY; without even the implied warranty of * * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU * * General Public License v2.0 for more details * * (http://www.gnu.org/licenses/gpl-2.0.html). * * * ***************************************************************************/ /* $Id: nsock_core.c 13728 2009-06-13 02:13:45Z david $ */ #include "nsock_internal.h" #include "gh_list.h" #include "filespace.h" #include #if HAVE_ERRNO_H #include #endif #if HAVE_SYS_TYPES_H #include #endif #if HAVE_SYS_SOCKET_H #include #endif #if HAVE_NETINET_IN_H #include #endif #if HAVE_ARPA_INET_H #include #endif #if HAVE_STRING_H #include #endif #include "netutils.h" #if HAVE_PCAP #include "nsock_pcap.h" static int pcap_read_on_nonselect(mspool *nsp); #endif /* Msock time of day -- we update this at least once per nsock_loop round (and after most calls that are likely to block). Other nsock files should grab this */ struct timeval nsock_tod; /* Returns -1 (and sets ms->errno if there is an error so severe that we might as well quit waiting and have nsock_loop() return an error */ static int wait_for_events(mspool *ms, int msec_timeout) { int event_msecs; /* Msecs before an event goes off */ int combined_msecs; int sock_err = 0; struct timeval select_tv; struct timeval *select_tv_p; assert(msec_timeout >= -1); if (ms->evl.events_pending == 0) return 0; /* No need to wait on 0 events ... */ do { if (ms->tracelevel > 3) nsock_trace(ms, "wait_for_events"); if (ms->evl.next_ev.tv_sec == 0) { event_msecs = -1; /* None of the events specified a timeout */ } else { event_msecs = MAX(0, TIMEVAL_MSEC_SUBTRACT(ms->evl.next_ev, nsock_tod)); } /* We cast to unsigned because we want -1 to be very high (since it means no timeout) */ combined_msecs = MIN((unsigned) event_msecs, (unsigned) msec_timeout); /* printf("wait_for_events: starting wait -- combined_msecs=%d\n", combined_msecs); */ /* Set up the timeval pointer we will give to select() */ memset(&select_tv, 0, sizeof(select_tv)); if (combined_msecs > 0) { select_tv.tv_sec = combined_msecs / 1000; select_tv.tv_usec = (combined_msecs % 1000) * 1000; select_tv_p = &select_tv; } else if (combined_msecs == 0) { /* we want the tv_sec and tv_usec to be zero -- but they already are from bzero */ select_tv_p = &select_tv; } else { assert(combined_msecs == -1); select_tv_p = NULL; } #if HAVE_PCAP /* do non-blocking read on pcap devices that doesn't support select() * If there is anything read, don't do usleep() or select(), just leave this loop */ if (pcap_read_on_nonselect(ms)) { /* okay, something was read. */ } else #endif { /* Set up the descriptors for select */ ms->mioi.fds_results_r = ms->mioi.fds_master_r; ms->mioi.fds_results_w = ms->mioi.fds_master_w; ms->mioi.fds_results_x = ms->mioi.fds_master_x; ms->mioi.results_left = fselect(ms->mioi.max_sd + 1, &ms->mioi.fds_results_r, &ms->mioi.fds_results_w, &ms->mioi.fds_results_x, select_tv_p); if (ms->mioi.results_left == -1) sock_err = socket_errno(); } gettimeofday(&nsock_tod, NULL); /* Due to usleep or select delay */ } while (ms->mioi.results_left == -1 && sock_err == EINTR);// repeat only if signal occured if (ms->mioi.results_left == -1 && sock_err != EINTR) { nsock_trace(ms, "nsock_loop error %d: %s", sock_err, strerror(sock_err)); ms->errnum = sock_err; return -1; } return 0; } /* A handler function is defined for each of the main event types (read, write, connect, timer, etc) -- the handler is called when new information is available for the event. The handler makes any neccessary updates to the event based on any new information available. If the event becomes ready for delivery, the handler sets nse->event_done and fills out the relevant event fields (status, errnum) as applicable. The handlers also take care of event type specific teardown (such as clearing socket descriptors from select/poll lists). If event_done is not set, the handler will be called again in the case of more information or an event timeout */ /* The event type handlers -- the first three arguments of each are the same: mspool *ms msevent *nse -- the event we have new info on enum nse_status -- The reason for the call, usually NSE_STATUS_SUCCESS (which generally means a successful I/O call or NSE_STATUS_TIMEOUT or NSE_STATUS_CANCELLED Some of the event type handlers have other parameters, specific to their needs. All the handlers can assume that the calling function has checked that select or poll said their descriptors were readable/writeable (as appropriate). The idea is that each handler will take care of the stuff that is specific to it and the calling function will handle the stuff that can be generalized to dispatching/deleting/etc. all events. But the calling function may use type-specific info to determine whether the handler should be called at all (to save CPU time). */ /* handle_connect_results assumes that select or poll have already shown the descriptor to be active */ void handle_connect_result(mspool *ms, msevent *nse, enum nse_status status) { int optval; socklen_t optlen = sizeof(int); char buf[1024]; msiod *iod = nse->iod; #if HAVE_OPENSSL int sslerr; int sslconnect_inprogress = nse->type == NSE_TYPE_CONNECT_SSL && iod->ssl; #else int sslconnect_inprogress = 0; #endif int rc; rc = 0; if (status == NSE_STATUS_TIMEOUT || status == NSE_STATUS_CANCELLED) { nse->status = status; nse->event_done = 1; } else if (sslconnect_inprogress) { /* Do nothing */ } else if (status == NSE_STATUS_SUCCESS) { /* First we want to determine whether the socket really is connected */ if (getsockopt(iod->sd, SOL_SOCKET, SO_ERROR, (char *) &optval, &optlen) != 0) optval = socket_errno(); /* Stupid Solaris */ switch(optval) { case 0: #ifdef LINUX if (!FD_ISSET(iod->sd, &ms->mioi.fds_results_r)) { /* Linux goofiness -- We need to actually test that it is writeable */ rc = send(iod->sd, "", 0, 0); if (rc < 0 ) { nse->status = NSE_STATUS_ERROR; nse->errnum = ECONNREFUSED; } else { nse->status = NSE_STATUS_SUCCESS; } } else { nse->status = NSE_STATUS_SUCCESS; } #else nse->status = NSE_STATUS_SUCCESS; #endif break; case ECONNREFUSED: case EHOSTUNREACH: case ENETDOWN: case ENETUNREACH: case ENETRESET: case ECONNABORTED: case ETIMEDOUT: case EHOSTDOWN: case ECONNRESET: #ifdef WIN32 case WSAEADDRNOTAVAIL: #endif #ifndef WIN32 case EPIPE: /* Has been seen after connect on Linux. */ case ENOPROTOOPT: /* Also seen on Linux, perhaps in response to protocol unreachable. */ #endif nse->status = NSE_STATUS_ERROR; nse->errnum = optval; break; default: Snprintf(buf, sizeof(buf), "Strange connect error from %s (%d)", inet_ntop_ez(&iod->peer, iod->peerlen), optval); perror(buf); assert(0); /* I'd like for someone to report it */ break; } /* Now special code for the SSL case where the TCP connection was successful. */ if (nse->type == NSE_TYPE_CONNECT_SSL && nse->status == NSE_STATUS_SUCCESS) { #if HAVE_OPENSSL assert(ms->sslctx != NULL); iod->ssl = SSL_new(ms->sslctx); if (!iod->ssl) fatal("SSL_new failed: %s", ERR_error_string(ERR_get_error(), NULL)); /* Associate our new SSL with the connected socket. It will inherit the non-blocking nature of the sd */ if (SSL_set_fd(iod->ssl, iod->sd) != 1) { fatal("SSL_set_fd failed: %s", ERR_error_string(ERR_get_error(), NULL)); } /* Event not done -- need to do SSL connect below */ nse->sslinfo.ssl_desire = SSL_ERROR_WANT_CONNECT; #endif } else { /* This is not an SSL connect (in which case we are always done), or the TCP connect() underlying the SSL failed (in which case we are also done */ nse->event_done = 1; } } else { assert(0); /* Currently we only know about TIMEOUT and SUCCESS callbacks */ } /* Clear the socket descriptors from all the lists -- we might put it back on some of them in the SSL case */ if (iod->sd != -1) { FD_CLR(iod->sd, &ms->mioi.fds_master_r); FD_CLR(iod->sd, &ms->mioi.fds_master_w); FD_CLR(iod->sd, &ms->mioi.fds_master_x); FD_CLR(iod->sd, &ms->mioi.fds_results_r); FD_CLR(iod->sd, &ms->mioi.fds_results_w); FD_CLR(iod->sd, &ms->mioi.fds_results_x); if (ms->mioi.max_sd == iod->sd) ms->mioi.max_sd--; } #if HAVE_OPENSSL if (nse->type == NSE_TYPE_CONNECT_SSL && !nse->event_done) { /* Lets now start/continue/finish the connect! */ if (iod->ssl_session) { rc = SSL_set_session(iod->ssl, iod->ssl_session); if (rc == 0) { printf("Uh-oh: SSL_set_session() failed - please tell Fyodor\n"); } iod->ssl_session = NULL; /* No need for this any more */ } rc = SSL_connect(iod->ssl); /* printf("DBG: SSL_connect()=%d", rc); */ if (rc == 1) { /* Woop! Connect is done! */ nse->event_done = 1; /* Check that certificate verification was okay, if requested. */ if (nsi_ssl_post_connect_verify(iod)) { nse->status = NSE_STATUS_SUCCESS; } else { if (ms->tracelevel > 0) { nsock_trace(ms, "certificate verification error for EID %li: %s", nse->id, ERR_error_string(ERR_get_error(), NULL)); } nse->status = NSE_STATUS_ERROR; } } else { sslerr = SSL_get_error(iod->ssl, rc); if (rc == -1 && sslerr == SSL_ERROR_WANT_READ) { nse->sslinfo.ssl_desire = sslerr; FD_SET(iod->sd, &ms->mioi.fds_master_r); ms->mioi.max_sd = MAX(ms->mioi.max_sd, iod->sd); } else if (rc == -1 && sslerr == SSL_ERROR_WANT_WRITE) { nse->sslinfo.ssl_desire = sslerr; FD_SET(iod->sd, &ms->mioi.fds_master_w); ms->mioi.max_sd = MAX(ms->mioi.max_sd, iod->sd); } else { /* Unexpected error */ if (ms->tracelevel > 0) nsock_trace(ms, "EID %li %s", nse->id, ERR_error_string(ERR_get_error(), NULL)); nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = EIO; } } } #endif return; } void handle_write_result(mspool *ms, msevent *nse, enum nse_status status) { int bytesleft; char *str; int res; int err; msiod *iod = nse->iod; if (status == NSE_STATUS_TIMEOUT || status == NSE_STATUS_CANCELLED) { nse->event_done = 1; nse->status = status; } else if (status == NSE_STATUS_SUCCESS) { str = FILESPACE_STR(&nse->iobuf) + nse->writeinfo.written_so_far; bytesleft = FILESPACE_LENGTH(&nse->iobuf) - nse->writeinfo.written_so_far; assert(bytesleft > 0); #if HAVE_OPENSSL if (iod->ssl) res = SSL_write(iod->ssl, str, bytesleft); else #endif res = send(nse->iod->sd, str, bytesleft, 0); if (res == bytesleft) { nse->event_done = 1; nse->status = NSE_STATUS_SUCCESS; } else if (res >= 0) { nse->writeinfo.written_so_far += res; } else { assert(res == -1); if (iod->ssl) { #if HAVE_OPENSSL err = SSL_get_error(iod->ssl, res); if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE ) { nse->sslinfo.ssl_desire = err; } else { /* Unexpected error */ nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = EIO; } #endif } else { err = socket_errno(); if (err != EINTR && err != EAGAIN #ifndef WIN32 && err != EBUSY #endif ) { nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = err; } } } } if (nse->event_done && nse->iod->sd != -1) { /* Decrement the count of waiting writes on this IOD. When it hits 0 we remove it from the descriptor lists. */ iod->writesd_count--; assert(iod->writesd_count >= 0); if (!iod->ssl && iod->writesd_count == 0) { FD_CLR(iod->sd, &ms->mioi.fds_master_w); FD_CLR(iod->sd, &ms->mioi.fds_results_w); } else if (iod->ssl && iod->events_pending <= 1) { /* Exception: If this is an SSL socket and there is another pending event (such as a read), it might actually be waiting on a write so we can't clear in that case */ FD_CLR(iod->sd, &ms->mioi.fds_master_r); FD_CLR(iod->sd, &ms->mioi.fds_results_r); FD_CLR(iod->sd, &ms->mioi.fds_master_w); FD_CLR(iod->sd, &ms->mioi.fds_results_w); } /* Note -- I only want to decrement IOD if there are no other events hinging on it. For example, there could be a READ and WRITE outstanding at once */ if (nse->iod->events_pending <= 1 && ms->mioi.max_sd == nse->iod->sd) ms->mioi.max_sd--; } return; } void handle_timer_result(mspool *ms, msevent *nse, enum nse_status status) { /* Ooh this is a hard job :) */ nse->event_done = 1; nse->status = status; return; } /* Returns -1 if an error, otherwise the number of newly written bytes */ static int do_actual_read(mspool *ms, msevent *nse) { char buf[8192]; int buflen = 0; msiod *iod = nse->iod; int err = 0; int max_chunk = NSOCK_READ_CHUNK_SIZE; int startlen = FILESPACE_LENGTH(&nse->iobuf); if (nse->readinfo.read_type == NSOCK_READBYTES) max_chunk = nse->readinfo.num; if (!iod->ssl) { /* Traditional read() - no SSL - using recv() because that works better on Windows */ do { buflen = recv(iod->sd, buf, sizeof(buf), 0); /* Using recv() was failing, at least on UNIX, for non-network sockets (i.e. stdin) * in this case, a read() is done - as on ENOTSOCK we may have a non-network socket */ if (buflen == -1 && socket_errno() == ENOTSOCK) buflen = read(iod->sd, buf, sizeof(buf)); if (buflen == -1) err = socket_errno(); if (buflen > 0) { if (fscat(&nse->iobuf, buf, buflen) == -1) { nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = ENOMEM; return -1; } /* Sometimes a service just spews and spews data. So we return * after a somewhat large amount to avoid monopolizing resources * and avoid DOS attacks. */ if (FILESPACE_LENGTH(&nse->iobuf) > max_chunk) return FILESPACE_LENGTH(&nse->iobuf) - startlen; /* No good reason to read again if we we were successful in the read but * didn't fill up the buffer. Espcecially for UDP, where we want to * return only one datagram at a time. */ if (buflen > 0 && buflen < sizeof(buf)) return FILESPACE_LENGTH(&nse->iobuf) - startlen; } } while (buflen > 0 || (buflen == -1 && err == EINTR)); if (buflen == -1) { if (err != EINTR && err != EAGAIN) { nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = err; return -1; } } } else { #if HAVE_OPENSSL /* OpenSSL read */ while ((buflen = SSL_read(iod->ssl, buf, sizeof(buf))) > 0) { if (fscat(&nse->iobuf, buf, buflen) == -1) { nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = ENOMEM; return -1; } /* Sometimes a service just spews and spews data. So we return * after a somewhat large amount to avoid monopolizing resources * and avoid DOS attacks. */ if (FILESPACE_LENGTH(&nse->iobuf) > NSOCK_READ_CHUNK_SIZE) return FILESPACE_LENGTH(&nse->iobuf) - startlen; } if (buflen == -1) { err = SSL_get_error(iod->ssl, buflen); if (err == SSL_ERROR_WANT_READ || err == SSL_ERROR_WANT_WRITE ) { nse->sslinfo.ssl_desire = err; } else { /* Unexpected error */ nse->event_done = 1; nse->status = NSE_STATUS_ERROR; nse->errnum = EIO; if (ms->tracelevel > 2) nsock_trace(ms, "SSL_read() failed for reason %s on NSI %li", ERR_reason_error_string(err), iod->id); return -1; } } #endif /* HAVE_OPENSSL */ } if (buflen == 0) { nse->event_done = 1; nse->eof = 1; if (FILESPACE_LENGTH(&nse->iobuf) > 0) { nse->status = NSE_STATUS_SUCCESS; return FILESPACE_LENGTH(&nse->iobuf) - startlen; } else { nse->status = NSE_STATUS_EOF; return 0; } } return FILESPACE_LENGTH(&nse->iobuf) - startlen; } void handle_read_result(mspool *ms, msevent *nse, enum nse_status status) { unsigned int count; char *str; int rc, len; msiod *iod = nse->iod; if (status == NSE_STATUS_TIMEOUT) { nse->event_done = 1; if (FILESPACE_LENGTH(&nse->iobuf) > 0) { nse->status = NSE_STATUS_SUCCESS; } else { nse->status = NSE_STATUS_TIMEOUT; } } else if (status == NSE_STATUS_CANCELLED) { nse->status = status; nse->event_done = 1; } else if (status == NSE_STATUS_SUCCESS) { rc = do_actual_read(ms, nse); /* printf("DBG: Just read %d new bytes%s.\n", rc, iod->ssl? "( SSL!)" : ""); */ if (rc > 0) { /* We decide whether we have read enough to return */ switch(nse->readinfo.read_type) { case NSOCK_READ: nse->status = NSE_STATUS_SUCCESS; nse->event_done = 1; break; case NSOCK_READBYTES: if (FILESPACE_LENGTH(&nse->iobuf) >= nse->readinfo.num) { nse->status = NSE_STATUS_SUCCESS; nse->event_done = 1; } /* else we are not done */ break; case NSOCK_READLINES: /* Lets count the number of lines we have ... */ count = 0; len = FILESPACE_LENGTH(&nse->iobuf) -1; str = FILESPACE_STR(&nse->iobuf); for(count=0; len >= 0; len--) { if (str[len] == '\n') { count++; if ((int) count >= nse->readinfo.num) break; } } if ((int) count >= nse->readinfo.num) { nse->event_done = 1; nse->status = NSE_STATUS_SUCCESS; } /* Else we are not done */ break; default: assert(0); break; /* unreached */ } } } else { assert(0); /* Currently we only know about TIMEOUT, CANCELLED, and SUCCESS callbacks */ } /* If there are no more reads for this IOD, we are done reading on the socket so we can take it off the descriptor list ... */ if (nse->event_done && iod->sd >= 0) { /* Decrement the count of waiting reads on this IOD. When it hits 0 we remove it from the descriptor lists. */ iod->readsd_count--; assert(iod->readsd_count >= 0); if (!iod->ssl && iod->readsd_count == 0) { FD_CLR(iod->sd, &ms->mioi.fds_master_r); FD_CLR(iod->sd, &ms->mioi.fds_results_r); } else if (iod->ssl && iod->events_pending <= 1) { /* Exception: If this is an SSL socket and there is another pending event (such as a write), it might actually be waiting on a read so we can't clear in that case */ FD_CLR(iod->sd, &ms->mioi.fds_master_r); FD_CLR(iod->sd, &ms->mioi.fds_results_r); FD_CLR(iod->sd, &ms->mioi.fds_master_w); FD_CLR(iod->sd, &ms->mioi.fds_results_w); } /* Note -- I only want to decrement IOD if there are no other events hinging on it. * For example, there could be a READ and WRITE outstanding at once */ if (iod->events_pending <= 1 && ms->mioi.max_sd == iod->sd) ms->mioi.max_sd--; } #if HAVE_OPENSSL /* For SSL the type of listening we have to do varies. I can't clear the other type due to the possibility of a pending event needing it */ if (iod->ssl && nse->event_done == 0) { if (nse->sslinfo.ssl_desire == SSL_ERROR_WANT_READ) { FD_SET(iod->sd, &ms->mioi.fds_master_r); ms->mioi.max_sd = MAX(ms->mioi.max_sd, iod->sd); } else if (nse->sslinfo.ssl_desire == SSL_ERROR_WANT_WRITE) { FD_SET(iod->sd, &ms->mioi.fds_master_w); ms->mioi.max_sd = MAX(ms->mioi.max_sd, iod->sd); } } #endif /* HAVE_OPENSSL */ return; } #if HAVE_PCAP void handle_pcap_read_result(mspool *ms, msevent *nse, enum nse_status status) { msiod *iod = nse->iod; mspcap *mp = (mspcap *) iod->pcap; if (status == NSE_STATUS_TIMEOUT) { nse->status = NSE_STATUS_TIMEOUT; nse->event_done = 1; } else if (status == NSE_STATUS_CANCELLED) { nse->status = NSE_STATUS_CANCELLED; nse->event_done = 1; } else if (status == NSE_STATUS_SUCCESS) { /* check if we already have something read */ if(FILESPACE_LENGTH(&(nse->iobuf)) == 0){ nse->status = NSE_STATUS_TIMEOUT; nse->event_done = 0; }else{ nse->status = NSE_STATUS_SUCCESS;/* we have full buffer */ nse->event_done = 1; } } else { assert(0); /* Currently we only know about TIMEOUT, CANCELLED, and SUCCESS callbacks */ } /* If there are no more read events, we are done reading on the socket so we can take it off the descriptor list ... */ if (nse->event_done && mp->pcap_desc >= 0) { /* Decrement the count of waiting reads on this pcap descriptor. When it hits 0 we remove it from the descriptor lists. */ mp->readsd_count--; assert(mp->readsd_count >= 0); if (mp->readsd_count == 0) { FD_CLR(mp->pcap_desc, &ms->mioi.fds_master_r); FD_CLR(mp->pcap_desc, &ms->mioi.fds_results_r); } } return; } /* * returns number of descriptors on which data was read * */ static int pcap_read_on_nonselect(mspool *nsp) { gh_list *event_list = &nsp->evl.pcap_read_events; gh_list_elem *current, *next; msevent *nse; int rc; int ret = 0; for(current = GH_LIST_FIRST_ELEM(event_list); current != NULL; current = next) { nse = (msevent *) GH_LIST_ELEM_DATA(current); rc = do_actual_pcap_read(nse); if(rc==1){ /* something received */ ret++; break; } next = GH_LIST_ELEM_NEXT(current); } return(ret); } #endif // HAVE_PCAP /* Iterate through all the event lists (such as connect_events, read_events, timer_events, etc) and take action for those that have completed (due to timeout, i/o, etc) */ static void iterate_through_event_lists(mspool *nsp) { gh_list_elem *current, *next, *last; msevent *nse; int match_r = 0, match_w = 0; #if HAVE_OPENSSL int desire_r = 0, desire_w = 0; #endif gh_list *event_lists[] = { &nsp->evl.connect_events, &nsp->evl.read_events, &nsp->evl.write_events, &nsp->evl.timer_events, #if HAVE_PCAP &nsp->evl.pcap_read_events, #endif 0 }; int current_list_idx; nsp->evl.next_ev.tv_sec = 0; /* Clear it -- We will find the next event as we go through the list */ /* We keep the events seperate because we want to handle them in the order: connect => read => write => timer for several reasons: 1) Makes sure we have gone through all the net i/o events before a timer expires (would be a shame to timeout after the data was available but before we delivered the events 2) The connect() results often lead to a read or write that can be processed in the same cycle. In the same way, read() often leads to write(). */ /* foreach list */ if (nsp->tracelevel > 7){ for(current_list_idx = 0; event_lists[current_list_idx] != NULL; current_list_idx++) { nsock_trace(nsp, "before iterating, list %i", current_list_idx); for(current = GH_LIST_FIRST_ELEM(event_lists[current_list_idx]); current != NULL; current = GH_LIST_ELEM_NEXT(current)) { nse = (msevent *) GH_LIST_ELEM_DATA(current); nsock_trace(nsp, "before iterating %lu",nse->id); } } } /* foreach list */ for(current_list_idx = 0; event_lists[current_list_idx] != NULL; current_list_idx++) { /* Remember the last element and don't look past it. This is because, for example, handling a read event may add another read event to the end of the list, which then adds another, and so on. */ last = GH_LIST_LAST_ELEM(event_lists[current_list_idx]); /* foreach element in the list */ for(current = GH_LIST_FIRST_ELEM(event_lists[current_list_idx]); current != NULL && GH_LIST_ELEM_PREV(current) != last; current = next) { nse = (msevent *) GH_LIST_ELEM_DATA(current); if (nsp->tracelevel > 7) nsock_trace(nsp, "list %i, iterating %lu",current_list_idx, nse->id); if ( ! nse->event_done) { switch(nse->type) { case NSE_TYPE_CONNECT: case NSE_TYPE_CONNECT_SSL: if (FD_ISSET(nse->iod->sd, &nsp->mioi.fds_results_r) || FD_ISSET(nse->iod->sd, &nsp->mioi.fds_results_w) || FD_ISSET(nse->iod->sd, &nsp->mioi.fds_results_x)) { handle_connect_result(nsp, nse, NSE_STATUS_SUCCESS); } if (!nse->event_done && nse->timeout.tv_sec && TIMEVAL_MSEC_SUBTRACT(nse->timeout, nsock_tod) <= 0) { handle_connect_result(nsp, nse, NSE_STATUS_TIMEOUT); } break; case NSE_TYPE_READ: match_r = FD_ISSET(nse->iod->sd, &nsp->mioi.fds_results_r); match_w = FD_ISSET(nse->iod->sd, &nsp->mioi.fds_results_w); #if HAVE_OPENSSL desire_r = nse->sslinfo.ssl_desire == SSL_ERROR_WANT_READ; desire_w = nse->sslinfo.ssl_desire == SSL_ERROR_WANT_WRITE; if (nse->iod->ssl && ((desire_r && match_r) || (desire_w && match_w))) handle_read_result(nsp, nse, NSE_STATUS_SUCCESS); else #endif if (!nse->iod->ssl && match_r) handle_read_result(nsp, nse, NSE_STATUS_SUCCESS); if (!nse->event_done && nse->timeout.tv_sec && TIMEVAL_MSEC_SUBTRACT(nse->timeout, nsock_tod) <= 0) { handle_read_result(nsp, nse, NSE_STATUS_TIMEOUT); } break; case NSE_TYPE_WRITE: match_r = FD_ISSET(nse->iod->sd, &nsp->mioi.fds_results_r); match_w = FD_ISSET(nse->iod->sd, &nsp->mioi.fds_results_w); #if HAVE_OPENSSL desire_r = nse->sslinfo.ssl_desire == SSL_ERROR_WANT_READ; desire_w = nse->sslinfo.ssl_desire == SSL_ERROR_WANT_WRITE; if (nse->iod->ssl && ((desire_r && match_r) || (desire_w && match_w))) handle_write_result(nsp, nse, NSE_STATUS_SUCCESS); else #endif if (!nse->iod->ssl && match_w) handle_write_result(nsp, nse, NSE_STATUS_SUCCESS); if (!nse->event_done && nse->timeout.tv_sec && TIMEVAL_MSEC_SUBTRACT(nse->timeout, nsock_tod) <= 0) { handle_write_result(nsp, nse, NSE_STATUS_TIMEOUT); } break; case NSE_TYPE_TIMER: if (nse->timeout.tv_sec && TIMEVAL_MSEC_SUBTRACT(nse->timeout, nsock_tod) <= 0) { handle_timer_result(nsp, nse, NSE_STATUS_SUCCESS); } break; #if HAVE_PCAP case NSE_TYPE_PCAP_READ:{ if (nsp->tracelevel > 5) nsock_trace(nsp, "PCAP iterating %lu",nse->id); /* buffer empty? check it! */ if ( FILESPACE_LENGTH(&(nse->iobuf))==0 ) do_actual_pcap_read(nse); /* if already received smth */ if ( FILESPACE_LENGTH(&(nse->iobuf))>0 ) handle_pcap_read_result(nsp, nse, NSE_STATUS_SUCCESS); if (!nse->event_done && nse->timeout.tv_sec && TIMEVAL_MSEC_SUBTRACT(nse->timeout, nsock_tod) <= 0) handle_pcap_read_result(nsp, nse, NSE_STATUS_TIMEOUT); #if PCAP_BSD_SELECT_HACK /* If event occured, and we're in BSD_HACK mode, than this event was added * to two queues. evl.read_event and evl.pcap_read_event * Of coure we should destroy it only once. * I assume we're now in evl.read_event, co just unlink this event from * evl.pcap_read_event */ if(((mspcap *) nse->iod->pcap)->pcap_desc >= 0 && nse->event_done && event_lists[current_list_idx] == &nsp->evl.read_events){ /* event is done, list is read_events and we're in BSD_HACK mode. * So unlink event from pcap_read_events */ gh_list_remove(&nsp->evl.pcap_read_events, nse); if (nsp->tracelevel > 8) nsock_trace(nsp, "PCAP NSE #%lu: Removing event from PCAP_READ_EVENTS", nse->id); } if(((mspcap *) nse->iod->pcap)->pcap_desc >= 0 && nse->event_done && event_lists[current_list_idx] == &nsp->evl.pcap_read_events){ gh_list_remove(&nsp->evl.read_events, nse); if (nsp->tracelevel > 8) nsock_trace(nsp, "PCAP NSE #%lu: Removing event from READ_EVENTS", nse->id); } #endif break; } #endif default: fatal("Event has unknown type (%d)", nse->type); break; /* unreached */ } } if (nse->event_done) { if (nsp->tracelevel > 8) nsock_trace(nsp, "NSE #%lu: Removing event from event_lists[%i]", nse->id, current_list_idx); /* WooHoo! The event is ready to be sent */ msevent_dispatch_and_delete(nsp, nse, 1); next = GH_LIST_ELEM_NEXT(current); gh_list_remove_elem(event_lists[current_list_idx], current); } else { next = GH_LIST_ELEM_NEXT(current); /* Is this event the next-to-timeout? */ if (nse->timeout.tv_sec != 0) { if (nsp->evl.next_ev.tv_sec == 0) nsp->evl.next_ev = nse->timeout; else if (TIMEVAL_MSEC_SUBTRACT(nsp->evl.next_ev, nse->timeout) > 0) nsp->evl.next_ev = nse->timeout; } } } } } /* Here is the all important looping function that tells the event engine to start up and begin processing events. It will continue until all events have been delivered (including new ones started from event handlers), or the msec_timeout is reached, or a major error has occured. Use -1 if you don't want to set a maximum time for it to run. A timeout of 0 will return after 1 non-blocking loop. The nsock loop can be restarted again after it returns. For example you could do a series of 15 second runs, allowing you to do other stuff between them */ enum nsock_loopstatus nsock_loop(nsock_pool nsp, int msec_timeout) { mspool *ms = (mspool *) nsp; struct timeval loop_timeout; int msecs_left; unsigned long loopnum = 0; enum nsock_loopstatus quitstatus = NSOCK_LOOP_ERROR; gettimeofday(&nsock_tod, NULL); if (msec_timeout < -1) { ms->errnum = EINVAL; return NSOCK_LOOP_ERROR; } TIMEVAL_MSEC_ADD(loop_timeout, nsock_tod, msec_timeout); msecs_left = msec_timeout; if (ms->tracelevel > 1) { if (msec_timeout >= 0) { nsock_trace(ms, "nsock_loop() started (timeout=%dms). %d events pending", msec_timeout, ms->evl.events_pending); } else { nsock_trace(ms, "nsock_loop() started (no timeout). %d events pending", ms->evl.events_pending); } } while(1) { if (ms->evl.events_pending == 0) { /* if no events at all are pending, then none can be created until we quit nsock_loop() -- so we do that now. */ quitstatus = NSOCK_LOOP_NOEVENTS; break; } if (msec_timeout >= 0) { msecs_left = MAX(0, TIMEVAL_MSEC_SUBTRACT(loop_timeout, nsock_tod)); if (msecs_left == 0 && loopnum > 0) { quitstatus = NSOCK_LOOP_TIMEOUT; break; } } if (wait_for_events(ms, msecs_left) == -1) { quitstatus = NSOCK_LOOP_ERROR; break; } /* Now we go through the event lists, doing callbacks for those which have completed */ iterate_through_event_lists(ms); gettimeofday(&nsock_tod, NULL); /* we do this at end because there is one at beginning of function */ loopnum++; } return quitstatus; } /* Grab the latest time as recorded by the nsock library, which does so at least once per event loop (in main_loop). Not only does this function (generally) avoid a system call, but in many circumstances it is better to use nsock's time rather than the system time. If nsock has never obtained the time when you call it, it will do so before returning */ const struct timeval *nsock_gettimeofday() { if (nsock_tod.tv_sec == 0) gettimeofday(&nsock_tod, NULL); return &nsock_tod; } /* Adds an event to the appropriate nsp event list, handles housekeeping such as adjusting the descriptor select/poll lists, registering the timeout value, etc. */ void nsp_add_event(mspool *nsp, msevent *nse) { if (nsp->tracelevel > 5) nsock_trace(nsp, "NSE #%lu: Adding event", nse->id); /* First lets do the event-type independant stuff -- starting with timeouts */ if (nse->event_done) { nsp->evl.next_ev = nsock_tod; } else { if (nse->timeout.tv_sec != 0) { if (nsp->evl.next_ev.tv_sec == 0) { nsp->evl.next_ev = nse->timeout; } else if (TIMEVAL_MSEC_SUBTRACT(nsp->evl.next_ev, nse->timeout) > 0) { nsp->evl.next_ev = nse->timeout; } } } nsp->evl.events_pending++; /* Now we do the event type specific actions */ switch(nse->type) { case NSE_TYPE_CONNECT: case NSE_TYPE_CONNECT_SSL: if (!nse->event_done) { assert(nse->iod->sd >= 0); FD_SET( nse->iod->sd, &nsp->mioi.fds_master_r); FD_SET( nse->iod->sd, &nsp->mioi.fds_master_w); FD_SET( nse->iod->sd, &nsp->mioi.fds_master_x); nsp->mioi.max_sd = MAX(nsp->mioi.max_sd, nse->iod->sd); } gh_list_append(&nsp->evl.connect_events, nse); break; case NSE_TYPE_READ: if (!nse->event_done) { assert(nse->iod->sd >= 0); FD_SET( nse->iod->sd, &nsp->mioi.fds_master_r); nse->iod->readsd_count++; nsp->mioi.max_sd = MAX(nsp->mioi.max_sd, nse->iod->sd); #if HAVE_OPENSSL if (nse->iod->ssl) nse->sslinfo.ssl_desire = SSL_ERROR_WANT_READ; #endif } gh_list_append(&nsp->evl.read_events, nse); break; case NSE_TYPE_WRITE: if (!nse->event_done) { assert(nse->iod->sd >= 0); FD_SET( nse->iod->sd, &nsp->mioi.fds_master_w); nse->iod->writesd_count++; nsp->mioi.max_sd = MAX(nsp->mioi.max_sd, nse->iod->sd); #if HAVE_OPENSSL if (nse->iod->ssl) nse->sslinfo.ssl_desire = SSL_ERROR_WANT_WRITE; #endif } gh_list_append(&nsp->evl.write_events, nse); break; case NSE_TYPE_TIMER: gh_list_append(&nsp->evl.timer_events, nse); break; #if HAVE_PCAP case NSE_TYPE_PCAP_READ:{ mspcap *mp = (mspcap *) nse->iod->pcap; assert(mp); if(mp->pcap_desc >= 0){ /* pcap descriptor present */ if(!nse->event_done){ FD_SET(mp->pcap_desc, &nsp->mioi.fds_master_r); mp->readsd_count++; nsp->mioi.max_sd = MAX(nsp->mioi.max_sd, mp->pcap_desc); } if (nsp->tracelevel > 8) nsock_trace(nsp, "PCAP NSE #%lu: Adding event to READ_EVENTS", nse->id); gh_list_append(&nsp->evl.read_events, nse); #if PCAP_BSD_SELECT_HACK /* when using BSD hack we must do pcap_next() after select(). * Let's insert this pcap to bot queues, to selectable and nonselectable. * This will result in doing pcap_next_ex() just before select() */ if (nsp->tracelevel > 8) nsock_trace(nsp, "PCAP NSE #%lu: Adding event to PCAP_READ_EVENTS", nse->id); gh_list_append(&nsp->evl.pcap_read_events, nse); #endif }else{ /* pcap isn't selectable. Add it to pcap-specific queue. */ if (nsp->tracelevel > 8) nsock_trace(nsp, "PCAP NSE #%lu: Adding event to PCAP_READ_EVENTS", nse->id); gh_list_append(&nsp->evl.pcap_read_events, nse); } break; } #endif default: assert(0); break; /* unreached */ } } void nsock_trace(mspool *ms, char *fmt, ...) { va_list ap; int elapsedTimeMS; elapsedTimeMS = TIMEVAL_MSEC_SUBTRACT(nsock_tod, ms->tracebasetime); va_start(ap, fmt); fflush(stdout); printf("NSOCK (%.4fs) ", elapsedTimeMS / 1000.0); vfprintf(stdout, fmt, ap); printf("\n"); va_end(ap); return; } /* An event has been completed and the handler is about to be called. This function writes out tracing data about the event if neccessary */ void nsock_trace_handler_callback(mspool *ms, msevent *nse) { msiod *nsi; char *str; int strlength = 0; char displaystr[256]; char errstr[256]; if (ms->tracelevel == 0) return; nsi = nse->iod; if (nse->status == NSE_STATUS_ERROR) { Snprintf(errstr, sizeof(errstr), "[%s (%d)] ", strerror(nse->errnum), nse->errnum); } else errstr[0] = '\0'; /* Some types have special tracing treatment */ switch(nse->type) { case NSE_TYPE_CONNECT: case NSE_TYPE_CONNECT_SSL: nsock_trace(ms, "Callback: %s %s %sfor EID %li [%s:%hu]", nse_type2str(nse->type), nse_status2str(nse->status), errstr, nse->id, inet_ntop_ez(&nsi->peer, nsi->peerlen), nsi_peerport(nsi)); break; case NSE_TYPE_READ: if (nse->status != NSE_STATUS_SUCCESS) { if (nsi->peerlen > 0) nsock_trace(ms, "Callback: %s %s %sfor EID %li [%s:%hu]", nse_type2str(nse->type), nse_status2str(nse->status), errstr, nse->id, inet_ntop_ez(&nsi->peer, nsi->peerlen), nsi_peerport(nsi)); else nsock_trace(ms, "Callback: %s %s %sfor EID %li (peer unspecified)", nse_type2str(nse->type), nse_status2str(nse->status), errstr, nse->id); } else { str = nse_readbuf(nse, &strlength); if (ms->tracelevel > 1 && strlength < 80) { memcpy(displaystr, ": ", 2); memcpy(displaystr + 2, str, strlength); displaystr[2 + strlength] = '\0'; replacenonprintable(displaystr + 2, strlength, '.'); } else displaystr[0] = '\0'; if (nsi->peerlen > 0) nsock_trace(ms, "Callback: %s %s for EID %li [%s:%hu] %s(%d bytes)%s", nse_type2str(nse->type), nse_status2str(nse->status), nse->id, inet_ntop_ez(&nsi->peer, nsi->peerlen), nsi_peerport(nsi), nse_eof(nse)? "[EOF]" : "", strlength, displaystr); else nsock_trace(ms, "Callback %s %s for EID %li (peer unspecified) %s(%d bytes)%s", nse_type2str(nse->type), nse_status2str(nse->status), nse->id, nse_eof(nse)? "[EOF]" : "", strlength, displaystr); } break; case NSE_TYPE_WRITE: nsock_trace(ms, "Callback: %s %s %sfor EID %li [%s:%hu]", nse_type2str(nse->type), nse_status2str(nse->status), errstr, nse->id, inet_ntop_ez(&nsi->peer, nsi->peerlen), nsi_peerport(nsi)); break; case NSE_TYPE_TIMER: nsock_trace(ms, "Callback: %s %s %sfor EID %li", nse_type2str(nse->type), nse_status2str(nse->status), errstr, nse->id); break; #if HAVE_PCAP case NSE_TYPE_PCAP_READ: nsock_trace(ms, "Callback: %s %s %sfor EID %li ", nse_type2str(nse->type), nse_status2str(nse->status), errstr, nse->id); break; #endif default: assert(0); break; } }