diff options
Diffstat (limited to 'tcpsyslog.c')
| -rw-r--r-- | tcpsyslog.c | 1236 |
1 files changed, 12 insertions, 1224 deletions
diff --git a/tcpsyslog.c b/tcpsyslog.c index 6b1c446c..d00731d3 100644 --- a/tcpsyslog.c +++ b/tcpsyslog.c @@ -1,5 +1,6 @@ /* tcpsyslog.c - * This is the implementation of TCP-based syslog. + * This is the implementation of TCP-based syslog. It includes those + * (few) things that both clients and servers need. * * File begun on 2007-07-20 by RGerhards (extracted from syslogd.c) * This file is under development and has not yet arrived at being fully @@ -9,19 +10,20 @@ * * Copyright 2007 Rainer Gerhards and Adiscon GmbH. * - * This program is free software; you can redistribute it and/or - * modify it under the terms of the GNU General Public License - * as published by the Free Software Foundation; either version 2 - * of the License, or (at your option) any later version. + * This file is part of rsyslog. * - * This program is distributed in the hope that it will be useful, + * Rsyslog is free software: you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation, either version 3 of the License, or + * (at your option) any later version. + * + * Rsyslog 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 for more details. * * You should have received a copy of the GNU General Public License - * along with this program; if not, write to the Free Software - * Foundation, Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA. + * along with Rsyslog. If not, see <http://www.gnu.org/licenses/>. * * A copy of the GPL can be found in the file "COPYING" in this distribution. */ @@ -42,1226 +44,12 @@ #if HAVE_FCNTL_H #include <fcntl.h> #endif -#if defined(SYSLOG_INET) && defined(USE_GSSAPI) -#include <gssapi/gssapi.h> -#endif #include "syslogd.h" #include "syslogd-types.h" #include "net.h" -#if defined(SYSLOG_INET) && defined(USE_GSSAPI) -#include "gss-misc.h" -#endif #include "tcpsyslog.h" -/******************************************************************** - * ### SYSLOG/TCP CODE ### - * This is code for syslog/tcp. This code would belong to a separate - * file - but I have put it here to avoid hassle with CVS. Over - * time, I expect rsyslog to utilize liblogging for actual network - * I/O. So the tcp code will be (re)moved some time. I don't like - * to add a new file to cvs that I will push to the attic in just - * a few weeks (month at most...). So I simply add the code here. - * - * Place no unrelated code between this comment and the - * END tcp comment! - * - * 2005-07-04 RGerhards (Happy independence day to our US friends!) - ********************************************************************/ -#ifdef SYSLOG_INET - -#define TCPSESS_MAX_DEFAULT 200 /* default for nbr of tcp sessions if no number is given */ - -static int iTCPSessMax = TCPSESS_MAX_DEFAULT; /* actual number of sessions */ -char *TCPLstnPort = "0"; /* read-only after startup */ -int bEnableTCP = 0; /* read-only after startup */ -int *sockTCPLstn = NULL; /* read-only after startup, modified by restart */ -struct TCPSession *pTCPSessions; -/* The thread-safeness of the sesion table is doubtful */ -#ifdef USE_GSSAPI -static gss_cred_id_t gss_server_creds = GSS_C_NO_CREDENTIAL; -char *gss_listen_service_name = NULL; -#endif - -/* configure TCP listener settings. This is called during command - * line parsing. The argument following -t is supplied as an argument. - * The format of this argument is - * "<port-to-use>, <nbr-of-sessions>" - * Typically, there is no whitespace between port and session number. - * (but it may be...). - * NOTE: you can not use dbgprintf() in here - the dbgprintf() system is - * not yet initilized when this function is called. - * rgerhards, 2007-06-21 - * We can also not use logerror(), as that system is also not yet - * initialized... rgerhards, 2007-06-28 - */ -void configureTCPListen(char *cOptarg) -{ - register int i; - register char *pArg = cOptarg; - - assert(cOptarg != NULL); - - /* extract port */ - i = 0; - while(isdigit((int) *pArg)) { - i = i * 10 + *pArg++ - '0'; - } - - if( i >= 0 && i <= 65535) { - TCPLstnPort = cOptarg; - } else { - fprintf(stderr, "rsyslogd: Invalid TCP listen port %d - changed to 514.\n", i); - TCPLstnPort = "514"; - } - - /* number of sessions */ - if(*pArg == ','){ - *pArg = '\0'; /* hack: terminates port (see a few lines above, same buffer!) */ - ++pArg; - while(isspace((int) *pArg)) - ++pArg; - /* ok, here should be the number... */ - i = 0; - while(isdigit((int) *pArg)) { - i = i * 10 + *pArg++ - '0'; - } - if(i > 1) - iTCPSessMax = i; - else { - /* too small, need to adjust */ - fprintf(stderr, - "rsyslogd: TCP session max configured to %d [-t %s] - changing to 1.\n", - i, cOptarg); - iTCPSessMax = 1; - } - } else if(*pArg == '\0') { - /* use default for session number - that's already set...*/ - /*EMPTY BY INTENSION*/ - } else { - fprintf(stderr, "rsyslogd: Invalid -t %s command line option.\n", cOptarg); - } -} - - -/* Initialize the session table - * returns 0 if OK, somewhat else otherwise - */ -static int TCPSessInit(void) -{ - register int i; - - assert(pTCPSessions == NULL); - dbgprintf("Allocating buffer for %d TCP sessions.\n", iTCPSessMax); - if((pTCPSessions = (struct TCPSession *) malloc(sizeof(struct TCPSession) * iTCPSessMax)) - == NULL) { - dbgprintf("Error: TCPSessInit() could not alloc memory for TCP session table.\n"); - return(1); - } - - for(i = 0 ; i < iTCPSessMax ; ++i) { - pTCPSessions[i].sock = -1; /* no sock */ - pTCPSessions[i].iMsg = 0; /* just make sure... */ - pTCPSessions[i].bAtStrtOfFram = 1; /* indicate frame header expected */ - pTCPSessions[i].eFraming = TCP_FRAMING_OCTET_STUFFING; /* just make sure... */ -#ifdef USE_GSSAPI - pTCPSessions[i].gss_flags = 0; - pTCPSessions[i].gss_context = GSS_C_NO_CONTEXT; - pTCPSessions[i].allowedMethods = 0; -#endif - } - return(0); -} - - -/* find a free spot in the session table. If the table - * is full, -1 is returned, else the index of the free - * entry (0 or higher). - */ -static int TCPSessFindFreeSpot(void) -{ - register int i; - - for(i = 0 ; i < iTCPSessMax ; ++i) { - if(pTCPSessions[i].sock == -1) - break; - } - - return((i < iTCPSessMax) ? i : -1); -} - - -/* Get the next session index. Free session tables entries are - * skipped. This function is provided the index of the last - * session entry, or -1 if no previous entry was obtained. It - * returns the index of the next session or -1, if there is no - * further entry in the table. Please note that the initial call - * might as well return -1, if there is no session at all in the - * session table. - */ -int TCPSessGetNxtSess(int iCurr) -{ - register int i; - - for(i = iCurr + 1 ; i < iTCPSessMax ; ++i) - if(pTCPSessions[i].sock != -1) - break; - - return((i < iTCPSessMax) ? i : -1); -} - - -/* De-Initialize TCP listner sockets. - * This function deinitializes everything, including freeing the - * session table. No TCP listen receive operations are permitted - * unless the subsystem is reinitialized. - * rgerhards, 2007-06-21 - */ -void deinit_tcp_listener(void) -{ - int iTCPSess; - - assert(pTCPSessions != NULL); - /* close all TCP connections! */ - iTCPSess = TCPSessGetNxtSess(-1); - while(iTCPSess != -1) { - int fd; - fd = pTCPSessions[iTCPSess].sock; - dbgprintf("Closing TCP Session %d\n", fd); - close(fd); - free(pTCPSessions[iTCPSess].fromHost); -#ifdef USE_GSSAPI - if(bEnableTCP & ALLOWEDMETHOD_GSS) { - OM_uint32 maj_stat, min_stat; - maj_stat = gss_delete_sec_context(&min_stat, &pTCPSessions[iTCPSess].gss_context, GSS_C_NO_BUFFER); - if (maj_stat != GSS_S_COMPLETE) - display_status("deleting context", maj_stat, min_stat); - } -#endif - /* now get next... */ - iTCPSess = TCPSessGetNxtSess(iTCPSess); - } - - /* we are done with the session table - so get rid of it... - */ - free(pTCPSessions); - pTCPSessions = NULL; /* just to make sure... */ - - /* finally close the listen sockets themselfs */ - freeAllSockets(&sockTCPLstn); -} - - -/* Initialize TCP sockets (for listener) - * This function returns either NULL (which means it failed) or - * a pointer to an array of file descriptiors. If the pointer is - * returned, the zeroest element [0] contains the count of valid - * descriptors. The descriptors themself follow in range - * [1] ... [num-descriptors]. It is guaranteed that each of these - * descriptors is valid, at least when this function returns. - * Please note that technically the array may be larger than the number - * of valid pointers stored in it. The memory overhead is minimal, so - * we do not bother to re-allocate an array of the exact size. Logically, - * the array still contains the exactly correct number of descriptors. - */ -int *create_tcp_socket(void) -{ - struct addrinfo hints, *res, *r; - int error, maxs, *s, *socks, on = 1; - - if(!strcmp(TCPLstnPort, "0")) - TCPLstnPort = "514"; - /* use default - we can not do service db update, because there is - * no IANA-assignment for syslog/tcp. In the long term, we might - * re-use RFC 3195 port of 601, but that would probably break to - * many existing configurations. - * rgerhards, 2007-06-28 - */ - memset(&hints, 0, sizeof(hints)); - hints.ai_flags = AI_PASSIVE | AI_NUMERICSERV; - hints.ai_family = family; - hints.ai_socktype = SOCK_STREAM; - - error = getaddrinfo(NULL, TCPLstnPort, &hints, &res); - if(error) { - logerror((char*) gai_strerror(error)); - return NULL; - } - - /* Count max number of sockets we may open */ - for (maxs = 0, r = res; r != NULL ; r = r->ai_next, maxs++) - /* EMPTY */; - socks = malloc((maxs+1) * sizeof(int)); - if (socks == NULL) { - logerror("couldn't allocate memory for TCP listen sockets, suspending TCP message reception."); - freeaddrinfo(res); - return NULL; - } - - *socks = 0; /* num of sockets counter at start of array */ - s = socks + 1; - for (r = res; r != NULL ; r = r->ai_next) { - *s = socket(r->ai_family, r->ai_socktype, r->ai_protocol); - if (*s < 0) { - if(!(r->ai_family == PF_INET6 && errno == EAFNOSUPPORT)) - logerror("create_udp_socket(), socket"); - /* it is debatable if PF_INET with EAFNOSUPPORT should - * also be ignored... - */ - continue; - } - -#ifdef IPV6_V6ONLY - if (r->ai_family == AF_INET6) { - int iOn = 1; - if (setsockopt(*s, IPPROTO_IPV6, IPV6_V6ONLY, - (char *)&iOn, sizeof (iOn)) < 0) { - logerror("TCP setsockopt"); - close(*s); - *s = -1; - continue; - } - } -#endif - if (setsockopt(*s, SOL_SOCKET, SO_REUSEADDR, - (char *) &on, sizeof(on)) < 0 ) { - logerror("TCP setsockopt(REUSEADDR)"); - close(*s); - *s = -1; - continue; - } - - /* We need to enable BSD compatibility. Otherwise an attacker - * could flood our log files by sending us tons of ICMP errors. - */ -#ifndef BSD - if (should_use_so_bsdcompat()) { - if (setsockopt(*s, SOL_SOCKET, SO_BSDCOMPAT, - (char *) &on, sizeof(on)) < 0) { - logerror("TCP setsockopt(BSDCOMPAT)"); - close(*s); - *s = -1; - continue; - } - } -#endif - - if( (bind(*s, r->ai_addr, r->ai_addrlen) < 0) -#ifndef IPV6_V6ONLY - && (errno != EADDRINUSE) -#endif - ) { - logerror("TCP bind"); - close(*s); - *s = -1; - continue; - } - - if( listen(*s,iTCPSessMax / 10 + 5) < 0) { - /* If the listen fails, it most probably fails because we ask - * for a too-large backlog. So in this case we first set back - * to a fixed, reasonable, limit that should work. Only if - * that fails, too, we give up. - */ - logerrorInt("listen with a backlog of %d failed - retrying with default of 32.", - iTCPSessMax / 10 + 5); - if(listen(*s, 32) < 0) { - logerror("TCP listen, suspending tcp inet"); - close(*s); - *s = -1; - continue; - } - } - - (*socks)++; - s++; - } - - if(res != NULL) - freeaddrinfo(res); - - if(Debug && *socks != maxs) - dbgprintf("We could initialize %d TCP listen sockets out of %d we received " - "- this may or may not be an error indication.\n", *socks, maxs); - - if(*socks == 0) { - logerror("No TCP listen socket could successfully be initialized, " - "message reception via TCP disabled.\n"); - free(socks); - return(NULL); - } - - /* OK, we had success. Now it is also time to - * initialize our connections - */ - if(TCPSessInit() != 0) { - /* OK, we are in some trouble - we could not initialize the - * session table, so we can not continue. We need to free all - * we have assigned so far, because we can not really use it... - */ - logerror("Could not initialize TCP session table, suspending TCP message reception."); - freeAllSockets(&socks); /* prevent a socket leak */ - return(NULL); - } - - return(socks); -} - - -/* Accept new TCP connection; make entry in session table. If there - * is no more space left in the connection table, the new TCP - * connection is immediately dropped. - */ -int TCPSessAccept(int fd) -{ - int newConn; - int iSess; - struct sockaddr_storage addr; - socklen_t addrlen = sizeof(struct sockaddr_storage); - size_t lenHostName; - uchar fromHost[NI_MAXHOST]; - uchar fromHostFQDN[NI_MAXHOST]; - char *pBuf; -#ifdef USE_GSSAPI - char allowedMethods = 0; -#endif - - newConn = accept(fd, (struct sockaddr*) &addr, &addrlen); - if (newConn < 0) { - logerror("tcp accept, ignoring error and connection request"); - return -1; - } - - /* Add to session list */ - iSess = TCPSessFindFreeSpot(); - if(iSess == -1) { - errno = 0; - logerror("too many tcp sessions - dropping incoming request"); - close(newConn); - return -1; - } - - /* OK, we have a "good" index... */ - /* get the host name */ - if(cvthname(&addr, fromHost, fromHostFQDN) != RS_RET_OK) { - /* we seem to have something malicous - at least we - * are now told to discard the connection request. - * Error message has been generated by cvthname. - */ - close (newConn); - return -1; - } - - /* Here we check if a host is permitted to send us - * syslog messages. If it isn't, we do not further - * process the message but log a warning (if we are - * configured to do this). - * rgerhards, 2005-09-26 - */ -#ifdef USE_GSSAPI - if((bEnableTCP & ALLOWEDMETHOD_TCP) && - isAllowedSender(pAllowedSenders_TCP, (struct sockaddr *)&addr, (char*)fromHostFQDN)) - allowedMethods |= ALLOWEDMETHOD_TCP; - if((bEnableTCP & ALLOWEDMETHOD_GSS) && - isAllowedSender(pAllowedSenders_GSS, (struct sockaddr *)&addr, (char*)fromHostFQDN)) - allowedMethods |= ALLOWEDMETHOD_GSS; - if(allowedMethods) - pTCPSessions[iSess].allowedMethods = allowedMethods; - else -#else - if(!isAllowedSender(pAllowedSenders_TCP, (struct sockaddr *)&addr, (char*)fromHostFQDN)) -#endif - { - dbgprintf("%s is not an allowed sender\n", (char *) fromHostFQDN); - if(option_DisallowWarning) { - errno = 0; - logerrorSz("TCP message from disallowed sender %s discarded", - (char*)fromHost); - } - close(newConn); - return -1; - } - - /* OK, we have an allowed sender, so let's continue */ - lenHostName = strlen((char*)fromHost) + 1; /* for \0 byte */ - if((pBuf = (char*) malloc(sizeof(char) * lenHostName)) == NULL) { - glblHadMemShortage = 1; - pTCPSessions[iSess].fromHost = "NO-MEMORY-FOR-HOSTNAME"; - } else { - memcpy(pBuf, fromHost, lenHostName); - pTCPSessions[iSess].fromHost = pBuf; - } - - pTCPSessions[iSess].sock = newConn; - pTCPSessions[iSess].iMsg = 0; /* init msg buffer! */ - return iSess; -} - - -/* This should be called before a normal (non forced) close - * of a TCP session. This function checks if there is any unprocessed - * message left in the TCP stream. Such a message is probably a - * fragement. If evrything goes well, we must be right at the - * beginnig of a new frame without any data received from it. If - * not, there is some kind of a framing error. I think I remember that - * some legacy syslog/TCP implementations have non-LF terminated - * messages at the end of the stream. For now, we allow this behaviour. - * Later, it should probably become a configuration option. - * rgerhards, 2006-12-07 - */ -void TCPSessPrepareClose(int iTCPSess) -{ - if(iTCPSess < 0 || iTCPSess > iTCPSessMax) { - errno = 0; - logerror("internal error, trying to close an invalid TCP session!"); - return; - } - - if(pTCPSessions[iTCPSess].bAtStrtOfFram == 1) { - /* this is how it should be. There is no unprocessed - * data left and such we have nothing to do. For simplicity - * reasons, we immediately return in that case. - */ - return; - } - - /* we have some data left! */ - if(pTCPSessions[iTCPSess].eFraming == TCP_FRAMING_OCTET_COUNTING) { - /* In this case, we have an invalid frame count and thus - * generate an error message and discard the frame. - */ - logerrorInt("Incomplete frame at end of stream in session %d - " - "ignoring extra data (a message may be lost).\n", - pTCPSessions[iTCPSess].sock); - /* nothing more to do */ - } else { /* here, we have traditional framing. Missing LF at the end - * of message may occur. As such, we process the message in - * this case. - */ - dbgprintf("Extra data at end of stream in legacy syslog/tcp message - processing\n"); - printchopped(pTCPSessions[iTCPSess].fromHost, pTCPSessions[iTCPSess].msg, - pTCPSessions[iTCPSess].iMsg, pTCPSessions[iTCPSess].sock, 1); - pTCPSessions[iTCPSess].bAtStrtOfFram = 1; - } -} - - -/* Closes a TCP session and marks its slot in the session - * table as unused. No attention is paid to the return code - * of close, so potential-double closes are not detected. - */ -void TCPSessClose(int iSess) -{ - if(iSess < 0 || iSess > iTCPSessMax) { - errno = 0; - logerror("internal error, trying to close an invalid TCP session!"); - return; - } - - close(pTCPSessions[iSess].sock); - pTCPSessions[iSess].sock = -1; - free(pTCPSessions[iSess].fromHost); - pTCPSessions[iSess].fromHost = NULL; /* not really needed, but... */ -} - - -/* Processes the data received via a TCP session. If there - * is no other way to handle it, data is discarded. - * Input parameter data is the data received, iLen is its - * len as returned from recv(). iLen must be 1 or more (that - * is errors must be handled by caller!). iTCPSess must be - * the index of the TCP session that received the data. - * rgerhards 2005-07-04 - * Changed this functions interface. We now return a status of - * what shall happen with the session. This is information for - * the caller. If 1 is returned, the session should remain open - * and additional data be accepted. If we return 0, the TCP - * session is to be closed by the caller. This functionality is - * needed in order to support framing errors, from which there - * is no recovery possible other than session termination and - * re-establishment. The need for this functionality thus is - * primarily rooted in support for -transport-tls I-D framing. - * rgerhards, 2006-12-07 - */ -int TCPSessDataRcvd(int iTCPSess, char *pData, int iLen) -{ - register int iMsg; - char *pMsg; - char *pEnd; - assert(pData != NULL); - assert(iLen > 0); - assert(iTCPSess >= 0); - assert(iTCPSess < iTCPSessMax); - assert(pTCPSessions[iTCPSess].sock != -1); - - /* We now copy the message to the session buffer. As - * it looks, we need to do this in any case because - * we might run into multiple messages inside a single - * buffer. Of course, we could think about optimizations, - * but as this code is to be replaced by liblogging, it - * probably doesn't make so much sense... - * rgerhards 2005-07-04 - * - * Algo: - * - copy message to buffer until the first LF is found - * - printline() the buffer - * - continue with copying - */ - iMsg = pTCPSessions[iTCPSess].iMsg; /* copy for speed */ - pMsg = pTCPSessions[iTCPSess].msg; /* just a shortcut */ - pEnd = pData + iLen; /* this is one off, which is intensional */ - - while(pData < pEnd) { - /* Check if we are at a new frame */ - if(pTCPSessions[iTCPSess].bAtStrtOfFram) { - /* we need to look at the message and detect - * the framing mode used - *//* - * Contrary to -transport-tls, we accept leading zeros in the message - * length. We do this in the spirit of "Be liberal in what you accept, - * and conservative in what you send". We expect that including leading - * zeros could be a common coding error. - * rgerhards, 2006-12-07 - * The chairs of the IETF syslog-sec WG have announced that it is - * consensus to do the octet count on the SYSLOG-MSG part only. I am - * now changing the code to reflect this. Hopefully, it will not change - * once again (there can no compatibility layer programmed for this). - * To be on the save side, I just comment the code out. I mark these - * comments with "IETF20061218". - * rgerhards, 2006-12-19 - */ - if(isdigit((int) *pData)) { - int iCnt; /* the frame count specified */ - pTCPSessions[iTCPSess].eFraming = TCP_FRAMING_OCTET_COUNTING; - /* in this mode, we have OCTET-COUNT SP MSG - so we now need - * to extract the OCTET-COUNT and the SP and then extract - * the msg. - */ - iCnt = 0; - /* IETF20061218 int iNbrOctets = 0; / * number of octets already consumed */ - while(isdigit((int) *pData)) { - iCnt = iCnt * 10 + *pData - '0'; - /* IETF20061218 ++iNbrOctets; */ - ++pData; - } - dbgprintf("TCP Message with octet-counter, size %d.\n", iCnt); - if(*pData == ' ') { - ++pData; /* skip over SP */ - /* IETF20061218 ++iNbrOctets; */ - } else { - /* TODO: handle "invalid frame" case */ - logerrorInt("Framing Error in received TCP message: " - "delimiter is not SP but has ASCII value %d.\n", - *pData); - return(0); /* unconditional error exit */ - } - /* IETF20061218 pTCPSessions[iTCPSess].iOctetsRemain = iCnt - iNbrOctets; */ - pTCPSessions[iTCPSess].iOctetsRemain = iCnt; - if(pTCPSessions[iTCPSess].iOctetsRemain < 1) { - /* TODO: handle the case where the octet count is 0 or negative! */ - dbgprintf("Framing Error: invalid octet count\n"); - logerrorInt("Framing Error in received TCP message: " - "invalid octet count %d.\n", - pTCPSessions[iTCPSess].iOctetsRemain); - return(0); /* unconditional error exit */ - } - } else { - pTCPSessions[iTCPSess].eFraming = TCP_FRAMING_OCTET_STUFFING; - /* No need to do anything else here in this case */ - } - pTCPSessions[iTCPSess].bAtStrtOfFram = 0; /* done frame header */ - } - - /* now copy message until end of record */ - - if(iMsg >= MAXLINE) { - /* emergency, we now need to flush, no matter if - * we are at end of message or not... - */ - printchopped(pTCPSessions[iTCPSess].fromHost, pMsg, iMsg, - pTCPSessions[iTCPSess].sock, 1); - iMsg = 0; - /* we might think if it is better to ignore the rest of the - * message than to treat it as a new one. Maybe this is a good - * candidate for a configuration parameter... - * rgerhards, 2006-12-04 - */ - } - - if(*pData == '\n' && - pTCPSessions[iTCPSess].eFraming == TCP_FRAMING_OCTET_STUFFING) { /* record delemiter? */ - printchopped(pTCPSessions[iTCPSess].fromHost, pMsg, iMsg, - pTCPSessions[iTCPSess].sock, 1); - iMsg = 0; - pTCPSessions[iTCPSess].bAtStrtOfFram = 1; - ++pData; - } else { - /* IMPORTANT: here we copy the actual frame content to the message! */ - *(pMsg + iMsg++) = *pData++; - } - - if(pTCPSessions[iTCPSess].eFraming == TCP_FRAMING_OCTET_COUNTING) { - /* do we need to find end-of-frame via octet counting? */ - pTCPSessions[iTCPSess].iOctetsRemain--; - if(pTCPSessions[iTCPSess].iOctetsRemain < 1) { - /* we have end of frame! */ - printchopped(pTCPSessions[iTCPSess].fromHost, pMsg, iMsg, - pTCPSessions[iTCPSess].sock, 1); - iMsg = 0; - pTCPSessions[iTCPSess].bAtStrtOfFram = 1; - } - } - } - - pTCPSessions[iTCPSess].iMsg = iMsg; /* persist value */ - - return(1); /* successful return */ -} - - -#ifdef USE_GSSAPI -int TCPSessGSSInit(void) -{ - gss_buffer_desc name_buf; - gss_name_t server_name; - OM_uint32 maj_stat, min_stat; - - if (gss_server_creds != GSS_C_NO_CREDENTIAL) - return 0; - - name_buf.value = (gss_listen_service_name == NULL) ? "host" : gss_listen_service_name; - name_buf.length = strlen(name_buf.value) + 1; - maj_stat = gss_import_name(&min_stat, &name_buf, GSS_C_NT_HOSTBASED_SERVICE, &server_name); - if (maj_stat != GSS_S_COMPLETE) { - display_status("importing name", maj_stat, min_stat); - return -1; - } - - maj_stat = gss_acquire_cred(&min_stat, server_name, 0, - GSS_C_NULL_OID_SET, GSS_C_ACCEPT, - &gss_server_creds, NULL, NULL); - if (maj_stat != GSS_S_COMPLETE) { - display_status("acquiring credentials", maj_stat, min_stat); - return -1; - } - - gss_release_name(&min_stat, &server_name); - dbgprintf("GSS-API initialized\n"); - return 0; -} - - -int TCPSessGSSAccept(int fd) -{ - gss_buffer_desc send_tok, recv_tok; - gss_name_t client; - OM_uint32 maj_stat, min_stat, acc_sec_min_stat; - int iSess; - gss_ctx_id_t *context; - OM_uint32 *sess_flags; - int fdSess; - char allowedMethods; - - if ((iSess = TCPSessAccept(fd)) == -1) - return -1; - - allowedMethods = pTCPSessions[iSess].allowedMethods; - if (allowedMethods & ALLOWEDMETHOD_GSS) { - /* Buffer to store raw message in case that - * gss authentication fails halfway through. - */ - char buf[MAXLINE]; - int ret = 0; - - dbgprintf("GSS-API Trying to accept TCP session %d\n", iSess); - - fdSess = pTCPSessions[iSess].sock; - if (allowedMethods & ALLOWEDMETHOD_TCP) { - int len; - fd_set fds; - struct timeval tv; - - do { - FD_ZERO(&fds); - FD_SET(fdSess, &fds); - tv.tv_sec = 1; - tv.tv_usec = 0; - ret = select(fdSess + 1, &fds, NULL, NULL, &tv); - } while (ret < 0 && errno == EINTR); - if (ret < 0) { - logerrorInt("TCP session %d will be closed, error ignored\n", iSess); - TCPSessClose(iSess); - return -1; - } else if (ret == 0) { - dbgprintf("GSS-API Reverting to plain TCP\n"); - pTCPSessions[iSess].allowedMethods = ALLOWEDMETHOD_TCP; - return 0; - } - - do { - ret = recv(fdSess, buf, sizeof (buf), MSG_PEEK); - } while (ret < 0 && errno == EINTR); - if (ret <= 0) { - if (ret == 0) - dbgprintf("GSS-API Connection closed by peer\n"); - else - logerrorInt("TCP session %d will be closed, error ignored\n", iSess); - TCPSessClose(iSess); - return -1; - } - - if (ret < 4) { - dbgprintf("GSS-API Reverting to plain TCP\n"); - pTCPSessions[iSess].allowedMethods = ALLOWEDMETHOD_TCP; - return 0; - } else if (ret == 4) { - /* The client might has been interupted after sending - * the data length (4B), give him another chance. - */ - sleep(1); - do { - ret = recv(fdSess, buf, sizeof (buf), MSG_PEEK); - } while (ret < 0 && errno == EINTR); - if (ret <= 0) { - if (ret == 0) - dbgprintf("GSS-API Connection closed by peer\n"); - else - logerrorInt("TCP session %d will be closed, error ignored\n", iSess); - TCPSessClose(iSess); - return -1; - } - } - - len = ntohl((buf[0] << 24) - | (buf[1] << 16) - | (buf[2] << 8) - | buf[3]); - if ((ret - 4) < len || len == 0) { - dbgprintf("GSS-API Reverting to plain TCP\n"); - pTCPSessions[iSess].allowedMethods = ALLOWEDMETHOD_TCP; - return 0; - } - } - - context = &pTCPSessions[iSess].gss_context; - *context = GSS_C_NO_CONTEXT; - sess_flags = &pTCPSessions[iSess].gss_flags; - do { - if (recv_token(fdSess, &recv_tok) <= 0) { - logerrorInt("TCP session %d will be closed, error ignored\n", iSess); - TCPSessClose(iSess); - return -1; - } - maj_stat = gss_accept_sec_context(&acc_sec_min_stat, context, gss_server_creds, - &recv_tok, GSS_C_NO_CHANNEL_BINDINGS, &client, - NULL, &send_tok, sess_flags, NULL, NULL); - if (recv_tok.value) { - free(recv_tok.value); - recv_tok.value = NULL; - } - if (maj_stat != GSS_S_COMPLETE - && maj_stat != GSS_S_CONTINUE_NEEDED) { - gss_release_buffer(&min_stat, &send_tok); - if (*context != GSS_C_NO_CONTEXT) - gss_delete_sec_context(&min_stat, context, GSS_C_NO_BUFFER); - if ((allowedMethods & ALLOWEDMETHOD_TCP) && - (GSS_ROUTINE_ERROR(maj_stat) == GSS_S_DEFECTIVE_TOKEN)) { - dbgprintf("GSS-API Reverting to plain TCP\n"); - dbgprintf("tcp session socket with new data: #%d\n", fdSess); - if(TCPSessDataRcvd(iSess, buf, ret) == 0) { - logerrorInt("Tearing down TCP Session %d - see " - "previous messages for reason(s)\n", - iSess); - TCPSessClose(iSess); - return -1; - } - pTCPSessions[iSess].allowedMethods = ALLOWEDMETHOD_TCP; - return 0; - } - display_status("accepting context", maj_stat, - acc_sec_min_stat); - TCPSessClose(iSess); - return -1; - } - if (send_tok.length != 0) { - if (send_token(fdSess, &send_tok) < 0) { - gss_release_buffer(&min_stat, &send_tok); - logerrorInt("TCP session %d will be closed, error ignored\n", iSess); - if (*context != GSS_C_NO_CONTEXT) - gss_delete_sec_context(&min_stat, context, GSS_C_NO_BUFFER); - TCPSessClose(iSess); - return -1; - } - gss_release_buffer(&min_stat, &send_tok); - } - } while (maj_stat == GSS_S_CONTINUE_NEEDED); - - maj_stat = gss_display_name(&min_stat, client, &recv_tok, NULL); - if (maj_stat != GSS_S_COMPLETE) - display_status("displaying name", maj_stat, min_stat); - else - dbgprintf("GSS-API Accepted connection from: %s\n", recv_tok.value); - gss_release_name(&min_stat, &client); - gss_release_buffer(&min_stat, &recv_tok); - - dbgprintf("GSS-API Provided context flags:\n"); - display_ctx_flags(*sess_flags); - pTCPSessions[iSess].allowedMethods = ALLOWEDMETHOD_GSS; - } - - return 0; -} - - -int TCPSessGSSRecv(int iSess, void *buf, size_t buf_len) -{ - gss_buffer_desc xmit_buf, msg_buf; - gss_ctx_id_t *context; - OM_uint32 maj_stat, min_stat; - int fdSess; - int conf_state; - int state, len; - - fdSess = pTCPSessions[iSess].sock; - if ((state = recv_token(fdSess, &xmit_buf)) <= 0) - return state; - - context = &pTCPSessions[iSess].gss_context; - maj_stat = gss_unwrap(&min_stat, *context, &xmit_buf, &msg_buf, - &conf_state, (gss_qop_t *) NULL); - if (maj_stat != GSS_S_COMPLETE) { - display_status("unsealing message", maj_stat, min_stat); - if (xmit_buf.value) { - free(xmit_buf.value); - xmit_buf.value = 0; - } - return (-1); - } - if (xmit_buf.value) { - free(xmit_buf.value); - xmit_buf.value = 0; - } - - len = msg_buf.length < buf_len ? msg_buf.length : buf_len; - memcpy(buf, msg_buf.value, len); - gss_release_buffer(&min_stat, &msg_buf); - - return len; -} - - -void TCPSessGSSClose(int iSess) { - OM_uint32 maj_stat, min_stat; - gss_ctx_id_t *context; - - if(iSess < 0 || iSess > iTCPSessMax) { - errno = 0; - logerror("internal error, trying to close an invalid TCP session!"); - return; - } - - context = &pTCPSessions[iSess].gss_context; - maj_stat = gss_delete_sec_context(&min_stat, context, GSS_C_NO_BUFFER); - if (maj_stat != GSS_S_COMPLETE) - display_status("deleting context", maj_stat, min_stat); - *context = GSS_C_NO_CONTEXT; - pTCPSessions[iSess].gss_flags = 0; - pTCPSessions[iSess].allowedMethods = 0; - - TCPSessClose(iSess); -} - - -void TCPSessGSSDeinit(void) { - OM_uint32 maj_stat, min_stat; - - maj_stat = gss_release_cred(&min_stat, &gss_server_creds); - if (maj_stat != GSS_S_COMPLETE) - display_status("releasing credentials", maj_stat, min_stat); -} -#endif /* #ifdef USE_GSSAPI */ - - -#endif -/******************************************************************** - * ### END OF SYSLOG/TCP CODE ### - ********************************************************************/ - -/* ----------------------------------------------------------------- * - * CODE THAT SHALL GO INTO ITS OWN MODULE (SENDING) * - * ----------------------------------------------------------------- */ - -/* Initialize TCP sockets (for sender) - * This is done once per selector line, if not yet initialized. - */ -int TCPSendCreateSocket(struct addrinfo *addrDest) -{ - int fd; - struct addrinfo *r; - - r = addrDest; - - while(r != NULL) { - fd = socket(r->ai_family, r->ai_socktype, r->ai_protocol); - if (fd != -1) { - /* We can not allow the TCP sender to block syslogd, at least - * not in a single-threaded design. That would cause rsyslogd to - * loose input messages - which obviously also would affect - * other selector lines, too. So we do set it to non-blocking and - * handle the situation ourselfs (by discarding messages). IF we run - * dual-threaded, however, the situation is different: in this case, - * the receivers and the selector line processing are only loosely - * coupled via a memory buffer. Now, I think, we can afford the extra - * wait time. Thus, we enable blocking mode for TCP if we compile with - * pthreads. -- rgerhards, 2005-10-25 - * And now, we always run on multiple threads... -- rgerhards, 2007-12-20 - */ - if (connect (fd, r->ai_addr, r->ai_addrlen) != 0) { - if(errno == EINPROGRESS) { - /* this is normal - will complete later select */ - return fd; - } else { - char errStr[1024]; - dbgprintf("create tcp connection failed, reason %s\n", - rs_strerror_r(errno, errStr, sizeof(errStr))); - } - - } - else { - return fd; - } - close(fd); - } - else { - char errStr[1024]; - dbgprintf("couldn't create send socket, reason %s\n", rs_strerror_r(errno, errStr, sizeof(errStr))); - } - r = r->ai_next; - } - - dbgprintf("no working socket could be obtained\n"); - - return -1; -} - - - -/* Build frame based on selected framing - * This function was created by pulling code from TCPSend() - * on 2007-12-27 by rgerhards. Older comments are still relevant. - * - * In order to support compressed messages via TCP, we must support an - * octet-counting based framing (LF may be part of the compressed message). - * We are now supporting the same mode that is available in IETF I-D - * syslog-transport-tls-05 (current at the time of this writing). This also - * eases things when we go ahead and implement that framing. I have now made - * available two cases where this framing is used: either by explitely - * specifying it in the config file or implicitely when sending a compressed - * message. In the later case, compressed and uncompressed messages within - * the same session have different framings. If it is explicitely set to - * octet-counting, only this framing mode is used within the session. - * rgerhards, 2006-12-07 - */ -static rsRetVal TCPSendBldFrame(TCPFRAMINGMODE rqdFraming, char **pmsg, size_t *plen, int *pbMustBeFreed) -{ - DEFiRet; - TCPFRAMINGMODE framingToUse; - int bIsCompressed; - size_t len; - char *msg; - char *buf = NULL; /* if this is non-NULL, it MUST be freed before return! */ - - assert(plen != NULL); - assert(pbMustBeFreed != NULL); - assert(pmsg != NULL); - - msg = *pmsg; - len = *plen; - bIsCompressed = *msg == 'z'; /* cache this, so that we can modify the message buffer */ - /* select framing for this record. If we have a compressed record, we always need to - * use octet counting because the data potentially contains all control characters - * including LF. - */ - framingToUse = bIsCompressed ? TCP_FRAMING_OCTET_COUNTING : rqdFraming; - - /* now check if we need to add a line terminator. We need to - * copy the string in memory in this case, this is probably - * quicker than using writev and definitely quicker than doing - * two socket calls. - * rgerhards 2005-07-22 - * - * Some messages already contain a \n character at the end - * of the message. We append one only if we there is not - * already one. This seems the best fit, though this also - * means the message does not arrive unaltered at the final - * destination. But in the spirit of legacy syslog, this is - * probably the best to do... - * rgerhards 2005-07-20 - */ - - /* Build frame based on selected framing */ - if(framingToUse == TCP_FRAMING_OCTET_STUFFING) { - if((*(msg+len-1) != '\n')) { - /* in the malloc below, we need to add 2 to the length. The - * reason is that we a) add one character and b) len does - * not take care of the '\0' byte. Up until today, it was just - * +1 , which caused rsyslogd to sometimes dump core. - * I have added this comment so that the logic is not accidently - * changed again. rgerhards, 2005-10-25 - */ - if((buf = malloc((len + 2) * sizeof(char))) == NULL) { - /* extreme mem shortage, try to solve - * as good as we can. No point in calling - * any alarms, they might as well run out - * of memory (the risk is very high, so we - * do NOT risk that). If we have a message of - * more than 1 byte (what I guess), we simply - * overwrite the last character. - * rgerhards 2005-07-22 - */ - if(len > 1) { - *(msg+len-1) = '\n'; - } else { - /* we simply can not do anything in - * this case (its an error anyhow...). - */ - } - } else { - /* we got memory, so we can copy the message */ - memcpy(buf, msg, len); /* do not copy '\0' */ - *(buf+len) = '\n'; - *(buf+len+1) = '\0'; - msg = buf; /* use new one */ - ++len; /* care for the \n */ - } - } - } else { - /* Octect-Counting - * In this case, we need to always allocate a buffer. This is because - * we need to put a header in front of the message text - */ - char szLenBuf[16]; - int iLenBuf; - - /* important: the printf-mask is "%d<sp>" because there must be a - * space after the len! - *//* The chairs of the IETF syslog-sec WG have announced that it is - * consensus to do the octet count on the SYSLOG-MSG part only. I am - * now changing the code to reflect this. Hopefully, it will not change - * once again (there can no compatibility layer programmed for this). - * To be on the save side, I just comment the code out. I mark these - * comments with "IETF20061218". - * rgerhards, 2006-12-19 - */ - iLenBuf = snprintf(szLenBuf, sizeof(szLenBuf)/sizeof(char), "%d ", (int) len); - /* IETF20061218 iLenBuf = - snprintf(szLenBuf, sizeof(szLenBuf)/sizeof(char), "%d ", len + iLenBuf);*/ - - if((buf = malloc((len + iLenBuf) * sizeof(char))) == NULL) { - /* we are out of memory. This is an extreme situation. We do not - * call any alarm handlers because they most likely run out of mem, - * too. We are brave enough to call debug output, though. Other than - * that, there is nothing left to do. We can not sent the message (as - * in case of the other framing, because the message is incomplete. - * We could, however, send two chunks (header and text separate), but - * that would cause a lot of complexity in the code. So we think it - * is appropriate enough to just make sure we do not crash in this - * very unlikely case. For this, it is justified just to loose - * the message. Rgerhards, 2006-12-07 - */ - dbgprintf("Error: out of memory when building TCP octet-counted " - "frame. Message is lost, trying to continue.\n"); - ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY); - } - - memcpy(buf, szLenBuf, iLenBuf); /* header */ - memcpy(buf + iLenBuf, msg, len); /* message */ - len += iLenBuf; /* new message size */ - msg = buf; /* set message buffer */ - } - - /* frame building complete, on to actual sending */ - - *plen = len; - if(buf == NULL) { - /* msg not modified */ - *pbMustBeFreed = 0; - } else { - *pmsg = msg; - *pbMustBeFreed = 1; - } - -finalize_it: - return iRet; -} - - -/* Sends a TCP message. It is first checked if the - * session is open and, if not, it is opened. Then the send - * is tried. If it fails, one silent re-try is made. If the send - * fails again, an error status (-1) is returned. If all goes well, - * 0 is returned. The TCP session is NOT torn down. - * For now, EAGAIN is ignored (causing message loss) - but it is - * hard to do something intelligent in this case. With this - * implementation here, we can not block and/or defer. Things are - * probably a bit better when we move to liblogging. The alternative - * would be to enhance the current select server with buffering and - * write descriptors. This seems not justified, given the expected - * short life span of this code (and the unlikeliness of this event). - * rgerhards 2005-07-06 - * This function is now expected to stay. Libloging won't be used for - * that purpose. I have added the param "len", because it is known by the - * caller and so saves us some time. Also, it MUST be given because there - * may be NULs inside msg so that we can not rely on strlen(). Please note - * that the restrictions outlined above do not existin in multi-threaded - * mode, which we assume will now be most often used. So there is no - * real issue with the potential message loss in single-threaded builds. - * rgerhards, 2006-11-30 - * I greatly restructured the function to be more generic and work - * with function pointers. So it now can be used with any type of transport, - * as long as it follows stream semantics. This was initially done to - * support plain TCP and GSS via common code. - */ -int TCPSend(void *pData, char *msg, size_t len, TCPFRAMINGMODE rqdFraming, - rsRetVal (*initFunc)(void*), - rsRetVal (*sendFunc)(void*, char*, size_t), - rsRetVal (*prepRetryFunc)(void*)) -{ - DEFiRet; - int bDone = 0; - int retry = 0; - int bMsgMustBeFreed = 0;/* must msg be freed at end of function? 0 - no, 1 - yes */ - - assert(pData != NULL); - assert(msg != NULL); - assert(len > 0); - - CHKiRet(TCPSendBldFrame(rqdFraming, &msg, &len, &bMsgMustBeFreed)); - - while(!bDone) { /* loop is broken when send succeeds or error occurs */ - CHKiRet(initFunc(pData)); - iRet = sendFunc(pData, msg, len); - - if(iRet == RS_RET_OK || retry > 0) { - /* we are done - either we succeeded or the retry failed */ - bDone = 1; - } else { /* OK, one retry */ - ++retry; - CHKiRet(prepRetryFunc(pData)); /* try to recover */ - } - } - -finalize_it: - if(bMsgMustBeFreed) - free(msg); - return iRet; -} - - -/* ----------------------------------------------------------------- * - * END OF CODE THAT SHALL GO INTO ITS OWN MODULE * - * ----------------------------------------------------------------- */ - +#include "srUtils.h" -/* - * vi:set ai: +/* vi:set ai: */ |