diff options
Diffstat (limited to 'plugins/omgssapi/omgssapi.c')
| -rw-r--r-- | plugins/omgssapi/omgssapi.c | 685 |
1 files changed, 685 insertions, 0 deletions
diff --git a/plugins/omgssapi/omgssapi.c b/plugins/omgssapi/omgssapi.c new file mode 100644 index 00000000..7097d742 --- /dev/null +++ b/plugins/omgssapi/omgssapi.c @@ -0,0 +1,685 @@ +/* omgssapi.c + * This is the implementation of the build-in forwarding output module. + * + * NOTE: read comments in module-template.h to understand how this file + * works! + * + * Copyright 2007 Rainer Gerhards and Adiscon GmbH. + * + * This file is part of rsyslog. + * + * 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 Rsyslog. If not, see <http://www.gnu.org/licenses/>. + * + * A copy of the GPL can be found in the file "COPYING" in this distribution. + */ +#include "config.h" +#ifdef USE_GSSAPI +#include "rsyslog.h" +#include <stdio.h> +#include <stdarg.h> +#include <stdlib.h> +#include <string.h> +#include <time.h> +#include <netinet/in.h> +#include <netdb.h> +#include <fnmatch.h> +#include <assert.h> +#include <errno.h> +#include <ctype.h> +#include <unistd.h> +#ifdef USE_NETZIP +#include <zlib.h> +#endif +#include <pthread.h> +#include <gssapi/gssapi.h> +#include "syslogd.h" +#include "syslogd-types.h" +#include "srUtils.h" +#include "net.h" +#include "omfwd.h" +#include "template.h" +#include "msg.h" +#include "tcpsyslog.h" +#include "cfsysline.h" +#include "module-template.h" +#include "gss-misc.h" + +MODULE_TYPE_OUTPUT + +#define INET_SUSPEND_TIME 60 /* equal to 1 minute + * rgerhards, 2005-07-26: This was 3 minutes. As the + * same timer is used for tcp based syslog, we have + * reduced it. However, it might actually be worth + * thinking about a buffered tcp sender, which would be + * a much better alternative. When that happens, this + * time here can be re-adjusted to 3 minutes (or, + * even better, made configurable). + */ +#define INET_RETRY_MAX 30 /* maximum of retries for gethostbyname() */ + /* was 10, changed to 30 because we reduced INET_SUSPEND_TIME by one third. So + * this "fixes" some of implications of it (see comment on INET_SUSPEND_TIME). + * rgerhards, 2005-07-26 + */ + +/* internal structures + */ +DEF_OMOD_STATIC_DATA + +typedef struct _instanceData { + char f_hname[MAXHOSTNAMELEN+1]; + short sock; /* file descriptor */ + enum { /* TODO: we shoud revisit these definitions */ + eDestFORW, + eDestFORW_SUSP, + eDestFORW_UNKN + } eDestState; + int iRtryCnt; + struct addrinfo *f_addr; + int compressionLevel; /* 0 - no compression, else level for zlib */ + char *port; + TCPFRAMINGMODE tcp_framing; +# define FORW_UDP 0 +# define FORW_TCP 1 + /* following fields for TCP-based delivery */ + time_t ttSuspend; /* time selector was suspended */ + gss_ctx_id_t gss_context; + OM_uint32 gss_flags; +} instanceData; + +static char *gss_base_service_name = NULL; +static enum gss_mode_t { + GSSMODE_MIC, + GSSMODE_ENC +} gss_mode = GSSMODE_ENC; + +/* get the syslog forward port from selector_t. The passed in + * struct must be one that is setup for forwarding. + * rgerhards, 2007-06-28 + * We may change the implementation to try to lookup the port + * if it is unspecified. So far, we use the IANA default auf 514. + */ +char *getFwdSyslogPt(instanceData *pData) +{ + assert(pData != NULL); + if(pData->port == NULL) + return("514"); + else + return(pData->port); +} + +BEGINcreateInstance +CODESTARTcreateInstance +ENDcreateInstance + + +BEGINisCompatibleWithFeature +CODESTARTisCompatibleWithFeature + if(eFeat == sFEATURERepeatedMsgReduction) + iRet = RS_RET_OK; +ENDisCompatibleWithFeature + + +BEGINfreeInstance +OM_uint32 maj_stat, min_stat; +CODESTARTfreeInstance + switch (pData->eDestState) { + case eDestFORW: + case eDestFORW_SUSP: + freeaddrinfo(pData->f_addr); + /* fall through */ + case eDestFORW_UNKN: + if(pData->port != NULL) + free(pData->port); + break; + } + + if (pData->gss_context != GSS_C_NO_CONTEXT) { + maj_stat = gss_delete_sec_context(&min_stat, &pData->gss_context, GSS_C_NO_BUFFER); + if (maj_stat != GSS_S_COMPLETE) + display_status("deleting context", maj_stat, min_stat); + } + /* this is meant to be done when module is unloaded, + but since this module is static... + */ + if (gss_base_service_name != NULL) { + free(gss_base_service_name); + gss_base_service_name = NULL; + } + + /* final cleanup */ + if(pData->sock >= 0) + close(pData->sock); +ENDfreeInstance + + +BEGINdbgPrintInstInfo +CODESTARTdbgPrintInstInfo + printf("%s", pData->f_hname); +ENDdbgPrintInstInfo + + +/* CODE FOR SENDING TCP MESSAGES */ + +/* This function is called immediately before a send retry is attempted. + * It shall clean up whatever makes sense. + * rgerhards, 2007-12-28 + */ +static rsRetVal TCPSendGSSPrepRetry(void __attribute__((unused)) *pData) +{ + /* in case of TCP/GSS, there is nothing to do */ + return RS_RET_OK; +} + + +static rsRetVal TCPSendGSSInit(void *pvData) +{ + DEFiRet; + int s = -1; + char *base; + OM_uint32 maj_stat, min_stat, init_sec_min_stat, *sess_flags, ret_flags; + gss_buffer_desc out_tok, in_tok; + gss_buffer_t tok_ptr; + gss_name_t target_name; + gss_ctx_id_t *context; + instanceData *pData = (instanceData *) pvData; + + assert(pData != NULL); + + /* if the socket is already initialized, we are done */ + if(pData->sock > 0) + ABORT_FINALIZE(RS_RET_OK); + + base = (gss_base_service_name == NULL) ? "host" : gss_base_service_name; + out_tok.length = strlen(pData->f_hname) + strlen(base) + 2; + if ((out_tok.value = malloc(out_tok.length)) == NULL) { + ABORT_FINALIZE(RS_RET_OUT_OF_MEMORY); + } + strcpy(out_tok.value, base); + strcat(out_tok.value, "@"); + strcat(out_tok.value, pData->f_hname); + dbgprintf("GSS-API service name: %s\n", (char*) out_tok.value); + + tok_ptr = GSS_C_NO_BUFFER; + context = &pData->gss_context; + *context = GSS_C_NO_CONTEXT; + + maj_stat = gss_import_name(&min_stat, &out_tok, GSS_C_NT_HOSTBASED_SERVICE, &target_name); + free(out_tok.value); + out_tok.value = NULL; + out_tok.length = 0; + + if (maj_stat != GSS_S_COMPLETE) { + display_status("parsing name", maj_stat, min_stat); + goto fail; + } + + sess_flags = &pData->gss_flags; + *sess_flags = GSS_C_MUTUAL_FLAG; + if (gss_mode == GSSMODE_MIC) { + *sess_flags |= GSS_C_INTEG_FLAG; + } + if (gss_mode == GSSMODE_ENC) { + *sess_flags |= GSS_C_CONF_FLAG; + } + dbgprintf("GSS-API requested context flags:\n"); + display_ctx_flags(*sess_flags); + + do { + maj_stat = gss_init_sec_context(&init_sec_min_stat, GSS_C_NO_CREDENTIAL, context, + target_name, GSS_C_NO_OID, *sess_flags, 0, NULL, + tok_ptr, NULL, &out_tok, &ret_flags, NULL); + if (tok_ptr != GSS_C_NO_BUFFER) + free(in_tok.value); + + if (maj_stat != GSS_S_COMPLETE + && maj_stat != GSS_S_CONTINUE_NEEDED) { + display_status("initializing context", maj_stat, init_sec_min_stat); + goto fail; + } + + if (s == -1) + if ((s = pData->sock = TCPSendCreateSocket(pData->f_addr)) == -1) + goto fail; + + if (out_tok.length != 0) { + dbgprintf("GSS-API Sending init_sec_context token (length: %ld)\n", (long) out_tok.length); + if (send_token(s, &out_tok) < 0) { + goto fail; + } + } + gss_release_buffer(&min_stat, &out_tok); + + if (maj_stat == GSS_S_CONTINUE_NEEDED) { + dbgprintf("GSS-API Continue needed...\n"); + if (recv_token(s, &in_tok) <= 0) { + goto fail; + } + tok_ptr = &in_tok; + } + } while (maj_stat == GSS_S_CONTINUE_NEEDED); + + dbgprintf("GSS-API Provided context flags:\n"); + *sess_flags = ret_flags; + display_ctx_flags(*sess_flags); + + dbgprintf("GSS-API Context initialized\n"); + gss_release_name(&min_stat, &target_name); + +finalize_it: + return iRet; + + fail: + logerror("GSS-API Context initialization failed\n"); + gss_release_name(&min_stat, &target_name); + gss_release_buffer(&min_stat, &out_tok); + if (*context != GSS_C_NO_CONTEXT) { + gss_delete_sec_context(&min_stat, context, GSS_C_NO_BUFFER); + *context = GSS_C_NO_CONTEXT; + } + if (s != -1) + close(s); + pData->sock = -1; + return RS_RET_GSS_SENDINIT_ERROR; +} + + +static rsRetVal TCPSendGSSSend(void *pvData, char *msg, size_t len) +{ + int s; + gss_ctx_id_t *context; + OM_uint32 maj_stat, min_stat; + gss_buffer_desc in_buf, out_buf; + instanceData *pData = (instanceData *) pvData; + + assert(pData != NULL); + assert(msg != NULL); + assert(len > 0); + + s = pData->sock; + context = &pData->gss_context; + in_buf.value = msg; + in_buf.length = len; + maj_stat = gss_wrap(&min_stat, *context, (gss_mode == GSSMODE_ENC) ? 1 : 0, GSS_C_QOP_DEFAULT, + &in_buf, NULL, &out_buf); + if (maj_stat != GSS_S_COMPLETE) { + display_status("wrapping message", maj_stat, min_stat); + goto fail; + } + + if (send_token(s, &out_buf) < 0) { + goto fail; + } + gss_release_buffer(&min_stat, &out_buf); + + return RS_RET_OK; + + fail: + close(s); + pData->sock = -1; + gss_delete_sec_context(&min_stat, context, GSS_C_NO_BUFFER); + *context = GSS_C_NO_CONTEXT; + gss_release_buffer(&min_stat, &out_buf); + dbgprintf("message not (GSS/tcp)send"); + return RS_RET_GSS_SEND_ERROR; +} + + +/* try to resume connection if it is not ready + * rgerhards, 2007-08-02 + */ +static rsRetVal doTryResume(instanceData *pData) +{ + DEFiRet; + struct addrinfo *res; + struct addrinfo hints; + unsigned e; + + switch (pData->eDestState) { + case eDestFORW_SUSP: + iRet = RS_RET_OK; /* the actual check happens during doAction() only */ + pData->eDestState = eDestFORW; + break; + + case eDestFORW_UNKN: + /* The remote address is not yet known and needs to be obtained */ + dbgprintf(" %s\n", pData->f_hname); + memset(&hints, 0, sizeof(hints)); + /* port must be numeric, because config file syntax requests this */ + /* TODO: this code is a duplicate from cfline() - we should later create + * a common function. + */ + hints.ai_flags = AI_NUMERICSERV; + hints.ai_family = family; + hints.ai_socktype = SOCK_STREAM; + if((e = getaddrinfo(pData->f_hname, + getFwdSyslogPt(pData), &hints, &res)) == 0) { + dbgprintf("%s found, resuming.\n", pData->f_hname); + pData->f_addr = res; + pData->iRtryCnt = 0; + pData->eDestState = eDestFORW; + } else { + iRet = RS_RET_SUSPENDED; + } + break; + case eDestFORW: + /* rgerhards, 2007-09-11: this can not happen, but I've included it to + * a) make the compiler happy, b) detect any logic errors */ + assert(0); + break; + } + + return iRet; +} + + +BEGINtryResume +CODESTARTtryResume + iRet = doTryResume(pData); +ENDtryResume + +BEGINdoAction + char *psz; /* temporary buffering */ + register unsigned l; +CODESTARTdoAction + switch (pData->eDestState) { + case eDestFORW_SUSP: + dbgprintf("internal error in omgssapi.c, eDestFORW_SUSP in doAction()!\n"); + iRet = RS_RET_SUSPENDED; + break; + + case eDestFORW_UNKN: + dbgprintf("doAction eDestFORW_UNKN\n"); + iRet = doTryResume(pData); + break; + + case eDestFORW: + dbgprintf(" %s:%s/%s\n", pData->f_hname, getFwdSyslogPt(pData), "tcp-gssapi"); + pData->ttSuspend = time(NULL); + psz = (char*) ppString[0]; + l = strlen((char*) psz); + if (l > MAXLINE) + l = MAXLINE; + +# ifdef USE_NETZIP + /* Check if we should compress and, if so, do it. We also + * check if the message is large enough to justify compression. + * The smaller the message, the less likely is a gain in compression. + * To save CPU cycles, we do not try to compress very small messages. + * What "very small" means needs to be configured. Currently, it is + * hard-coded but this may be changed to a config parameter. + * rgerhards, 2006-11-30 + */ + if(pData->compressionLevel && (l > MIN_SIZE_FOR_COMPRESS)) { + Bytef out[MAXLINE+MAXLINE/100+12] = "z"; + uLongf destLen = sizeof(out) / sizeof(Bytef); + uLong srcLen = l; + int ret; + ret = compress2((Bytef*) out+1, &destLen, (Bytef*) psz, + srcLen, pData->compressionLevel); + dbgprintf("Compressing message, length was %d now %d, return state %d.\n", + l, (int) destLen, ret); + if(ret != Z_OK) { + /* if we fail, we complain, but only in debug mode + * Otherwise, we are silent. In any case, we ignore the + * failed compression and just sent the uncompressed + * data, which is still valid. So this is probably the + * best course of action. + * rgerhards, 2006-11-30 + */ + dbgprintf("Compression failed, sending uncompressed message\n"); + } else if(destLen+1 < l) { + /* only use compression if there is a gain in using it! */ + dbgprintf("there is gain in compression, so we do it\n"); + psz = (char*) out; + l = destLen + 1; /* take care for the "z" at message start! */ + } + ++destLen; + } +# endif + + CHKiRet_Hdlr(TCPSend(pData, psz, l, pData->tcp_framing, TCPSendGSSInit, TCPSendGSSSend, TCPSendGSSPrepRetry)) { + /* error! */ + dbgprintf("error forwarding via tcp, suspending\n"); + pData->eDestState = eDestFORW_SUSP; + iRet = RS_RET_SUSPENDED; + } + break; + } +ENDdoAction + + +BEGINparseSelectorAct + uchar *q; + int i; + int error; + int bErr; + struct addrinfo hints, *res; +CODESTARTparseSelectorAct +CODE_STD_STRING_REQUESTparseSelectorAct(1) + /* first check if this config line is actually for us + * The first test [*p == '>'] can be skipped if a module shall only + * support the newer slection syntax [:modname:]. This is in fact + * recommended for new modules. Please note that over time this part + * will be handled by rsyslogd itself, but for the time being it is + * a good compromise to do it at the module level. + * rgerhards, 2007-10-15 + */ + + if(!strncmp((char*) p, ":omgssapi:", sizeof(":omgssapi:") - 1)) { + p += sizeof(":omgssapi:") - 1; /* eat indicator sequence (-1 because of '\0'!) */ + } else { + ABORT_FINALIZE(RS_RET_CONFLINE_UNPROCESSED); + } + + /* ok, if we reach this point, we have something for us */ + if((iRet = createInstance(&pData)) != RS_RET_OK) + goto finalize_it; + + /* we are now after the protocol indicator. Now check if we should + * use compression. We begin to use a new option format for this: + * @(option,option)host:port + * The first option defined is "z[0..9]" where the digit indicates + * the compression level. If it is not given, 9 (best compression) is + * assumed. An example action statement might be: + * @@(z5,o)127.0.0.1:1400 + * Which means send via TCP with medium (5) compresion (z) to the local + * host on port 1400. The '0' option means that octet-couting (as in + * IETF I-D syslog-transport-tls) is to be used for framing (this option + * applies to TCP-based syslog only and is ignored when specified with UDP). + * That is not yet implemented. + * rgerhards, 2006-12-07 + */ + if(*p == '(') { + /* at this position, it *must* be an option indicator */ + do { + ++p; /* eat '(' or ',' (depending on when called) */ + /* check options */ + if(*p == 'z') { /* compression */ +# ifdef USE_NETZIP + ++p; /* eat */ + if(isdigit((int) *p)) { + int iLevel; + iLevel = *p - '0'; + ++p; /* eat */ + pData->compressionLevel = iLevel; + } else { + logerrorInt("Invalid compression level '%c' specified in " + "forwardig action - NOT turning on compression.", + *p); + } +# else + logerror("Compression requested, but rsyslogd is not compiled " + "with compression support - request ignored."); +# endif /* #ifdef USE_NETZIP */ + } else if(*p == 'o') { /* octet-couting based TCP framing? */ + ++p; /* eat */ + /* no further options settable */ + pData->tcp_framing = TCP_FRAMING_OCTET_COUNTING; + } else { /* invalid option! Just skip it... */ + logerrorInt("Invalid option %c in forwarding action - ignoring.", *p); + ++p; /* eat invalid option */ + } + /* the option processing is done. We now do a generic skip + * to either the next option or the end of the option + * block. + */ + while(*p && *p != ')' && *p != ',') + ++p; /* just skip it */ + } while(*p && *p == ','); /* Attention: do.. while() */ + if(*p == ')') + ++p; /* eat terminator, on to next */ + else + /* we probably have end of string - leave it for the rest + * of the code to handle it (but warn the user) + */ + logerror("Option block not terminated in gssapi forward action."); + } + /* extract the host first (we do a trick - we replace the ';' or ':' with a '\0') + * now skip to port and then template name. rgerhards 2005-07-06 + */ + for(q = p ; *p && *p != ';' && *p != ':' ; ++p) + /* JUST SKIP */; + + pData->port = NULL; + if(*p == ':') { /* process port */ + uchar * tmp; + + *p = '\0'; /* trick to obtain hostname (later)! */ + tmp = ++p; + for(i=0 ; *p && isdigit((int) *p) ; ++p, ++i) + /* SKIP AND COUNT */; + pData->port = malloc(i + 1); + if(pData->port == NULL) { + logerror("Could not get memory to store syslog forwarding port, " + "using default port, results may not be what you intend\n"); + /* we leave f_forw.port set to NULL, this is then handled by + * getFwdSyslogPt(). + */ + } else { + memcpy(pData->port, tmp, i); + *(pData->port + i) = '\0'; + } + } + + /* now skip to template */ + bErr = 0; + while(*p && *p != ';') { + if(*p && *p != ';' && !isspace((int) *p)) { + if(bErr == 0) { /* only 1 error msg! */ + bErr = 1; + errno = 0; + logerror("invalid selector line (port), probably not doing " + "what was intended"); + } + } + ++p; + } + + /* TODO: make this if go away! */ + if(*p == ';') { + *p = '\0'; /* trick to obtain hostname (later)! */ + strcpy(pData->f_hname, (char*) q); + *p = ';'; + } else + strcpy(pData->f_hname, (char*) q); + + /* process template */ + if((iRet = cflineParseTemplateName(&p, *ppOMSR, 0, OMSR_NO_RQD_TPL_OPTS, (uchar*) " StdFwdFmt")) + != RS_RET_OK) + goto finalize_it; + + /* first set the pData->eDestState */ + memset(&hints, 0, sizeof(hints)); + /* port must be numeric, because config file syntax requests this */ + hints.ai_flags = AI_NUMERICSERV; + hints.ai_family = family; + hints.ai_socktype = SOCK_STREAM; + if( (error = getaddrinfo(pData->f_hname, getFwdSyslogPt(pData), &hints, &res)) != 0) { + pData->eDestState = eDestFORW_UNKN; + pData->iRtryCnt = INET_RETRY_MAX; + pData->ttSuspend = time(NULL); + } else { + pData->eDestState = eDestFORW; + pData->f_addr = res; + } + + /* TODO: do we need to call freeInstance if we failed - this is a general question for + * all output modules. I'll address it lates as the interface evolves. rgerhards, 2007-07-25 + */ +CODE_STD_FINALIZERparseSelectorAct +ENDparseSelectorAct + + +BEGINneedUDPSocket +CODESTARTneedUDPSocket + iRet = RS_RET_TRUE; +ENDneedUDPSocket + + +BEGINmodExit +CODESTARTmodExit +ENDmodExit + + +BEGINqueryEtryPt +CODESTARTqueryEtryPt +CODEqueryEtryPt_STD_OMOD_QUERIES +ENDqueryEtryPt + + +/* set a new GSSMODE based on config directive */ +static rsRetVal setGSSMode(void __attribute__((unused)) *pVal, uchar *mode) +{ + if (!strcmp((char *) mode, "integrity")) { + gss_mode = GSSMODE_MIC; + free(mode); + dbgprintf("GSS-API gssmode set to GSSMODE_MIC\n"); + } else if (!strcmp((char *) mode, "encryption")) { + gss_mode = GSSMODE_ENC; + free(mode); + dbgprintf("GSS-API gssmode set to GSSMODE_ENC\n"); + } else { + logerrorSz("unknown gssmode parameter: %s", (char *) mode); + free(mode); + return RS_RET_ERR; + } + + return RS_RET_OK; +} + + +static rsRetVal resetConfigVariables(uchar __attribute__((unused)) *pp, void __attribute__((unused)) *pVal) +{ + gss_mode = GSSMODE_ENC; + if (gss_base_service_name != NULL) { + free(gss_base_service_name); + gss_base_service_name = NULL; + } + return RS_RET_OK; +} + + +BEGINmodInit() +CODESTARTmodInit + *ipIFVersProvided = 1; /* so far, we only support the initial definition */ +CODEmodInit_QueryRegCFSLineHdlr + CHKiRet(omsdRegCFSLineHdlr((uchar *)"gssforwardservicename", 0, eCmdHdlrGetWord, NULL, &gss_base_service_name, STD_LOADABLE_MODULE_ID)); + CHKiRet(omsdRegCFSLineHdlr((uchar *)"gssmode", 0, eCmdHdlrGetWord, setGSSMode, &gss_mode, STD_LOADABLE_MODULE_ID)); + CHKiRet(omsdRegCFSLineHdlr((uchar *)"resetconfigvariables", 1, eCmdHdlrCustomHandler, resetConfigVariables, NULL, STD_LOADABLE_MODULE_ID)); +ENDmodInit + +#endif /* #ifdef USE_GSSAPI */ +/* + * vi:set ai: + */ |