blob: dfa9dcfaca9d7e6c3e26a90a2cadb740993c18d9 [file] [log] [blame]
/*
* agent_trap.c
*/
/* Portions of this file are subject to the following copyright(s). See
* the Net-SNMP's COPYING file for more details and other copyrights
* that may apply:
*/
/*
* Portions of this file are copyrighted by:
* Copyright © 2003 Sun Microsystems, Inc. All rights reserved.
* Use is subject to license terms specified in the COPYING file
* distributed with the Net-SNMP package.
*/
/** @defgroup agent_trap Trap generation routines for mib modules to use
* @ingroup agent
*
* @{
*/
#include <net-snmp/net-snmp-config.h>
#include <net-snmp/net-snmp-features.h>
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#if HAVE_NETDB_H
#include <netdb.h>
#endif
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if TIME_WITH_SYS_TIME
# include <sys/time.h>
# include <time.h>
#else
# if HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# include <time.h>
# endif
#endif
#if HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#include <net-snmp/utilities.h>
#include <net-snmp/net-snmp-includes.h>
#include <net-snmp/agent/net-snmp-agent-includes.h>
#include <net-snmp/agent/agent_trap.h>
#include <net-snmp/agent/snmp_agent.h>
#include <net-snmp/agent/agent_callbacks.h>
#include <net-snmp/agent/agent_module_config.h>
#include <net-snmp/agent/mib_module_config.h>
#ifdef USING_AGENTX_PROTOCOL_MODULE
#include "agentx/protocol.h"
#endif
netsnmp_feature_child_of(agent_trap_all, libnetsnmpagent)
netsnmp_feature_child_of(trap_vars_with_context, agent_trap_all)
netsnmp_feature_child_of(remove_trap_session, agent_trap_all)
netsnmp_feature_child_of(send_v3trap,netsnmp_unused)
netsnmp_feature_child_of(send_trap_pdu,netsnmp_unused)
struct trap_sink {
netsnmp_session *sesp;
struct trap_sink *next;
int pdutype;
int version;
};
struct trap_sink *sinks = NULL;
const oid objid_enterprisetrap[] = { NETSNMP_NOTIFICATION_MIB };
const oid trap_version_id[] = { NETSNMP_SYSTEM_MIB };
const int enterprisetrap_len = OID_LENGTH(objid_enterprisetrap);
const int trap_version_id_len = OID_LENGTH(trap_version_id);
#define SNMPV2_TRAPS_PREFIX SNMP_OID_SNMPMODULES,1,1,5
const oid trap_prefix[] = { SNMPV2_TRAPS_PREFIX };
const oid cold_start_oid[] = { SNMPV2_TRAPS_PREFIX, 1 }; /* SNMPv2-MIB */
#define SNMPV2_TRAP_OBJS_PREFIX SNMP_OID_SNMPMODULES,1,1,4
const oid snmptrap_oid[] = { SNMPV2_TRAP_OBJS_PREFIX, 1, 0 };
const oid snmptrapenterprise_oid[] = { SNMPV2_TRAP_OBJS_PREFIX, 3, 0 };
const oid sysuptime_oid[] = { SNMP_OID_MIB2, 1, 3, 0 };
const size_t snmptrap_oid_len = OID_LENGTH(snmptrap_oid);
const size_t snmptrapenterprise_oid_len = OID_LENGTH(snmptrapenterprise_oid);
const size_t sysuptime_oid_len = OID_LENGTH(sysuptime_oid);
#define SNMPV2_COMM_OBJS_PREFIX SNMP_OID_SNMPMODULES,18,1
const oid agentaddr_oid[] = { SNMPV2_COMM_OBJS_PREFIX, 3, 0 };
const size_t agentaddr_oid_len = OID_LENGTH(agentaddr_oid);
const oid community_oid[] = { SNMPV2_COMM_OBJS_PREFIX, 4, 0 };
const size_t community_oid_len = OID_LENGTH(community_oid);
#if !defined(NETSNMP_DISABLE_SNMPV1) || !defined(NETSNMP_DISABLE_SNMPV2C)
char *snmp_trapcommunity = NULL;
#endif
#define SNMP_AUTHENTICATED_TRAPS_ENABLED 1
#define SNMP_AUTHENTICATED_TRAPS_DISABLED 2
long snmp_enableauthentraps = SNMP_AUTHENTICATED_TRAPS_DISABLED;
int snmp_enableauthentrapsset = 0;
/*
* Prototypes
*/
/*
* static int create_v1_trap_session (const char *, u_short, const char *);
* static int create_v2_trap_session (const char *, u_short, const char *);
* static int create_v2_inform_session (const char *, u_short, const char *);
* static void free_trap_session (struct trap_sink *sp);
* static void send_v1_trap (netsnmp_session *, int, int);
* static void send_v2_trap (netsnmp_session *, int, int, int);
*/
/*******************
*
* Trap session handling
*
*******************/
void
init_traps(void)
{
}
static void
free_trap_session(struct trap_sink *sp)
{
DEBUGMSGTL(("trap", "freeing callback trap session (%p, %p)\n", sp, sp->sesp));
snmp_close(sp->sesp);
free(sp);
}
int
add_trap_session(netsnmp_session * ss, int pdutype, int confirm,
int version)
{
if (snmp_callback_available(SNMP_CALLBACK_APPLICATION,
SNMPD_CALLBACK_REGISTER_NOTIFICATIONS) ==
SNMPERR_SUCCESS) {
/*
* something else wants to handle notification registrations
*/
struct agent_add_trap_args args;
DEBUGMSGTL(("trap", "adding callback trap sink (%p)\n", ss));
args.ss = ss;
args.confirm = confirm;
snmp_call_callbacks(SNMP_CALLBACK_APPLICATION,
SNMPD_CALLBACK_REGISTER_NOTIFICATIONS,
(void *) &args);
} else {
/*
* no other support exists, handle it ourselves.
*/
struct trap_sink *new_sink;
DEBUGMSGTL(("trap", "adding internal trap sink\n"));
new_sink = (struct trap_sink *) malloc(sizeof(*new_sink));
if (new_sink == NULL)
return 0;
new_sink->sesp = ss;
new_sink->pdutype = pdutype;
new_sink->version = version;
new_sink->next = sinks;
sinks = new_sink;
}
return 1;
}
#ifndef NETSNMP_FEATURE_REMOVE_REMOVE_TRAP_SESSION
int
remove_trap_session(netsnmp_session * ss)
{
struct trap_sink *sp = sinks, *prev = NULL;
DEBUGMSGTL(("trap", "removing trap sessions\n"));
while (sp) {
if (sp->sesp == ss) {
if (prev) {
prev->next = sp->next;
} else {
sinks = sp->next;
}
/*
* I don't believe you *really* want to close the session here;
* it may still be in use for other purposes. In particular this
* is awkward for AgentX, since we want to call this function
* from the session's callback. Let's just free the trapsink
* data structure. [jbpn]
*/
/*
* free_trap_session(sp);
*/
DEBUGMSGTL(("trap", "removing trap session (%p, %p)\n", sp, sp->sesp));
free(sp);
return 1;
}
prev = sp;
sp = sp->next;
}
return 0;
}
#endif /* NETSNMP_FEATURE_REMOVE_REMOVE_TRAP_SESSION */
#if !defined(NETSNMP_DISABLE_SNMPV1) || !defined(NETSNMP_DISABLE_SNMPV2C)
static int
create_trap_session2(const char *sink, const char* sinkport,
char *com, int version, int pdutype)
{
netsnmp_transport *t;
netsnmp_session session, *sesp;
memset(&session, 0, sizeof(netsnmp_session));
session.version = version;
if (com) {
session.community = (u_char *) com;
session.community_len = strlen(com);
}
/*
* for informs, set retries to default
*/
if (SNMP_MSG_INFORM == pdutype) {
session.timeout = SNMP_DEFAULT_TIMEOUT;
session.retries = SNMP_DEFAULT_RETRIES;
}
/*
* if the sink is localhost, bind to localhost, to reduce open ports.
*/
if ((NULL == netsnmp_ds_get_string(NETSNMP_DS_LIBRARY_ID,
NETSNMP_DS_LIB_CLIENT_ADDR)) &&
((0 == strcmp("localhost",sink)) || (0 == strcmp("127.0.0.1",sink))))
session.localname = strdup("localhost");
t = netsnmp_tdomain_transport_full("snmptrap", sink, 0, NULL, sinkport);
if (t != NULL) {
sesp = snmp_add(&session, t, NULL, NULL);
if (sesp) {
return add_trap_session(sesp, pdutype,
(pdutype == SNMP_MSG_INFORM), version);
}
}
/*
* diagnose snmp_open errors with the input netsnmp_session pointer
*/
snmp_sess_perror("snmpd: create_trap_session", &session);
return 0;
}
int
create_trap_session(char *sink, u_short sinkport,
char *com, int version, int pdutype)
{
char buf[sizeof(sinkport) * 3 + 2];
if (sinkport != 0) {
sprintf(buf, ":%hu", sinkport);
snmp_log(LOG_NOTICE,
"Using a separate port number is deprecated, please correct "
"the sink specification instead");
}
return create_trap_session2(sink, sinkport ? buf : NULL, com, version,
pdutype);
}
#endif /* support for community based SNMP */
#ifndef NETSNMP_DISABLE_SNMPV1
static int
create_v1_trap_session(char *sink, const char *sinkport, char *com)
{
return create_trap_session2(sink, sinkport, com,
SNMP_VERSION_1, SNMP_MSG_TRAP);
}
#endif
#ifndef NETSNMP_DISABLE_SNMPV2C
static int
create_v2_trap_session(const char *sink, const char *sinkport, char *com)
{
return create_trap_session2(sink, sinkport, com,
SNMP_VERSION_2c, SNMP_MSG_TRAP2);
}
static int
create_v2_inform_session(const char *sink, const char *sinkport, char *com)
{
return create_trap_session2(sink, sinkport, com,
SNMP_VERSION_2c, SNMP_MSG_INFORM);
}
#endif
void
snmpd_free_trapsinks(void)
{
struct trap_sink *sp = sinks;
DEBUGMSGTL(("trap", "freeing trap sessions\n"));
while (sp) {
sinks = sinks->next;
free_trap_session(sp);
sp = sinks;
}
}
/*******************
*
* Trap handling
*
*******************/
netsnmp_pdu*
convert_v2pdu_to_v1( netsnmp_pdu* template_v2pdu )
{
netsnmp_pdu *template_v1pdu;
netsnmp_variable_list *first_vb, *vblist;
netsnmp_variable_list *var;
/*
* Make a copy of the v2 Trap PDU
* before starting to convert this
* into a v1 Trap PDU.
*/
template_v1pdu = snmp_clone_pdu( template_v2pdu);
if (!template_v1pdu) {
snmp_log(LOG_WARNING,
"send_trap: failed to copy v1 template PDU\n");
return NULL;
}
template_v1pdu->command = SNMP_MSG_TRAP;
first_vb = template_v1pdu->variables;
vblist = template_v1pdu->variables;
/*
* The first varbind should be the system uptime.
*/
if (!vblist ||
snmp_oid_compare(vblist->name, vblist->name_length,
sysuptime_oid, sysuptime_oid_len)) {
snmp_log(LOG_WARNING,
"send_trap: no v2 sysUptime varbind to set from\n");
snmp_free_pdu(template_v1pdu);
return NULL;
}
template_v1pdu->time = *vblist->val.integer;
vblist = vblist->next_variable;
/*
* The second varbind should be the snmpTrapOID.
*/
if (!vblist ||
snmp_oid_compare(vblist->name, vblist->name_length,
snmptrap_oid, snmptrap_oid_len)) {
snmp_log(LOG_WARNING,
"send_trap: no v2 trapOID varbind to set from\n");
snmp_free_pdu(template_v1pdu);
return NULL;
}
/*
* Check the v2 varbind list for any varbinds
* that are not valid in an SNMPv1 trap.
* This basically means Counter64 values.
*
* RFC 2089 said to omit such varbinds from the list.
* RFC 2576/3584 say to drop the trap completely.
*/
for (var = vblist->next_variable; var; var = var->next_variable) {
if ( var->type == ASN_COUNTER64 ) {
snmp_log(LOG_WARNING,
"send_trap: v1 traps can't carry Counter64 varbinds\n");
snmp_free_pdu(template_v1pdu);
return NULL;
}
}
/*
* Set the generic & specific trap types,
* and the enterprise field from the v2 varbind list.
* If there's an agentIPAddress varbind, set the agent_addr too
*/
if (!snmp_oid_compare(vblist->val.objid, OID_LENGTH(trap_prefix),
trap_prefix, OID_LENGTH(trap_prefix))) {
/*
* For 'standard' traps, extract the generic trap type
* from the snmpTrapOID value, and take the enterprise
* value from the 'snmpEnterprise' varbind.
*/
template_v1pdu->trap_type =
vblist->val.objid[OID_LENGTH(trap_prefix)] - 1;
template_v1pdu->specific_type = 0;
var = find_varbind_in_list( vblist,
snmptrapenterprise_oid,
snmptrapenterprise_oid_len);
if (var) {
template_v1pdu->enterprise_length = var->val_len/sizeof(oid);
template_v1pdu->enterprise =
snmp_duplicate_objid(var->val.objid,
template_v1pdu->enterprise_length);
} else {
template_v1pdu->enterprise = NULL;
template_v1pdu->enterprise_length = 0; /* XXX ??? */
}
} else {
/*
* For enterprise-specific traps, split the snmpTrapOID value
* into enterprise and specific trap
*/
size_t len = vblist->val_len / sizeof(oid);
if ( len <= 2 ) {
snmp_log(LOG_WARNING,
"send_trap: v2 trapOID too short (%d)\n", (int)len);
snmp_free_pdu(template_v1pdu);
return NULL;
}
template_v1pdu->trap_type = SNMP_TRAP_ENTERPRISESPECIFIC;
template_v1pdu->specific_type = vblist->val.objid[len - 1];
len--;
if (vblist->val.objid[len-1] == 0)
len--;
SNMP_FREE(template_v1pdu->enterprise);
template_v1pdu->enterprise =
snmp_duplicate_objid(vblist->val.objid, len);
template_v1pdu->enterprise_length = len;
}
var = find_varbind_in_list( vblist, agentaddr_oid,
agentaddr_oid_len);
if (var) {
memcpy(template_v1pdu->agent_addr,
var->val.string, 4);
}
/*
* The remainder of the v2 varbind list is kept
* as the v2 varbind list. Update the PDU and
* free the two redundant varbinds.
*/
template_v1pdu->variables = vblist->next_variable;
vblist->next_variable = NULL;
snmp_free_varbind( first_vb );
return template_v1pdu;
}
netsnmp_pdu*
convert_v1pdu_to_v2( netsnmp_pdu* template_v1pdu )
{
netsnmp_pdu *template_v2pdu;
netsnmp_variable_list *var;
oid enterprise[MAX_OID_LEN];
size_t enterprise_len;
/*
* Make a copy of the v1 Trap PDU
* before starting to convert this
* into a v2 Trap PDU.
*/
template_v2pdu = snmp_clone_pdu( template_v1pdu);
if (!template_v2pdu) {
snmp_log(LOG_WARNING,
"send_trap: failed to copy v2 template PDU\n");
return NULL;
}
template_v2pdu->command = SNMP_MSG_TRAP2;
/*
* Insert an snmpTrapOID varbind before the original v1 varbind list
* either using one of the standard defined trap OIDs,
* or constructing this from the PDU enterprise & specific trap fields
*/
if (template_v1pdu->trap_type == SNMP_TRAP_ENTERPRISESPECIFIC) {
memcpy(enterprise, template_v1pdu->enterprise,
template_v1pdu->enterprise_length*sizeof(oid));
enterprise_len = template_v1pdu->enterprise_length;
enterprise[enterprise_len++] = 0;
enterprise[enterprise_len++] = template_v1pdu->specific_type;
} else {
memcpy(enterprise, cold_start_oid, sizeof(cold_start_oid));
enterprise[9] = template_v1pdu->trap_type+1;
enterprise_len = sizeof(cold_start_oid)/sizeof(oid);
}
var = NULL;
if (!snmp_varlist_add_variable( &var,
snmptrap_oid, snmptrap_oid_len,
ASN_OBJECT_ID,
(u_char*)enterprise, enterprise_len*sizeof(oid))) {
snmp_log(LOG_WARNING,
"send_trap: failed to insert copied snmpTrapOID varbind\n");
snmp_free_pdu(template_v2pdu);
return NULL;
}
var->next_variable = template_v2pdu->variables;
template_v2pdu->variables = var;
/*
* Insert a sysUptime varbind at the head of the v2 varbind list
*/
var = NULL;
if (!snmp_varlist_add_variable( &var,
sysuptime_oid, sysuptime_oid_len,
ASN_TIMETICKS,
(u_char*)&(template_v1pdu->time),
sizeof(template_v1pdu->time))) {
snmp_log(LOG_WARNING,
"send_trap: failed to insert copied sysUptime varbind\n");
snmp_free_pdu(template_v2pdu);
return NULL;
}
var->next_variable = template_v2pdu->variables;
template_v2pdu->variables = var;
/*
* Append the other three conversion varbinds,
* (snmpTrapAgentAddr, snmpTrapCommunity & snmpTrapEnterprise)
* if they're not already present.
* But don't bomb out completely if there are problems.
*/
var = find_varbind_in_list( template_v2pdu->variables,
agentaddr_oid, agentaddr_oid_len);
if (!var && (template_v1pdu->agent_addr[0]
|| template_v1pdu->agent_addr[1]
|| template_v1pdu->agent_addr[2]
|| template_v1pdu->agent_addr[3])) {
if (!snmp_varlist_add_variable( &(template_v2pdu->variables),
agentaddr_oid, agentaddr_oid_len,
ASN_IPADDRESS,
(u_char*)&(template_v1pdu->agent_addr),
sizeof(template_v1pdu->agent_addr)))
snmp_log(LOG_WARNING,
"send_trap: failed to append snmpTrapAddr varbind\n");
}
var = find_varbind_in_list( template_v2pdu->variables,
community_oid, community_oid_len);
if (!var && template_v1pdu->community) {
if (!snmp_varlist_add_variable( &(template_v2pdu->variables),
community_oid, community_oid_len,
ASN_OCTET_STR,
template_v1pdu->community,
template_v1pdu->community_len))
snmp_log(LOG_WARNING,
"send_trap: failed to append snmpTrapCommunity varbind\n");
}
var = find_varbind_in_list( template_v2pdu->variables,
snmptrapenterprise_oid,
snmptrapenterprise_oid_len);
if (!var) {
if (!snmp_varlist_add_variable( &(template_v2pdu->variables),
snmptrapenterprise_oid, snmptrapenterprise_oid_len,
ASN_OBJECT_ID,
(u_char*)template_v1pdu->enterprise,
template_v1pdu->enterprise_length*sizeof(oid)))
snmp_log(LOG_WARNING,
"send_trap: failed to append snmpEnterprise varbind\n");
}
return template_v2pdu;
}
/**
* This function allows you to make a distinction between generic
* traps from different classes of equipment. For example, you may want
* to handle a SNMP_TRAP_LINKDOWN trap for a particular device in a
* different manner to a generic system SNMP_TRAP_LINKDOWN trap.
*
*
* @param trap is the generic trap type. The trap types are:
* - SNMP_TRAP_COLDSTART:
* cold start
* - SNMP_TRAP_WARMSTART:
* warm start
* - SNMP_TRAP_LINKDOWN:
* link down
* - SNMP_TRAP_LINKUP:
* link up
* - SNMP_TRAP_AUTHFAIL:
* authentication failure
* - SNMP_TRAP_EGPNEIGHBORLOSS:
* egp neighbor loss
* - SNMP_TRAP_ENTERPRISESPECIFIC:
* enterprise specific
*
* @param specific is the specific trap value.
*
* @param enterprise is an enterprise oid in which you want to send specific
* traps from.
*
* @param enterprise_length is the length of the enterprise oid, use macro,
* OID_LENGTH, to compute length.
*
* @param vars is used to supply list of variable bindings to form an SNMPv2
* trap.
*
* @param context currently unused
*
* @param flags currently unused
*
* @return void
*
* @see send_easy_trap
* @see send_v2trap
*/
int
netsnmp_send_traps(int trap, int specific,
const oid * enterprise, int enterprise_length,
netsnmp_variable_list * vars,
const char * context, int flags)
{
netsnmp_pdu *template_v1pdu;
netsnmp_pdu *template_v2pdu;
netsnmp_variable_list *vblist = NULL;
netsnmp_variable_list *trap_vb;
netsnmp_variable_list *var;
in_addr_t *pdu_in_addr_t;
u_long uptime;
struct trap_sink *sink;
const char *v1trapaddress;
int res = 0;
DEBUGMSGTL(( "trap", "send_trap %d %d ", trap, specific));
DEBUGMSGOID(("trap", enterprise, enterprise_length));
DEBUGMSG(( "trap", "\n"));
if (vars) {
vblist = snmp_clone_varbind( vars );
if (!vblist) {
snmp_log(LOG_WARNING,
"send_trap: failed to clone varbind list\n");
return -1;
}
}
if ( trap == -1 ) {
/*
* Construct the SNMPv2-style notification PDU
*/
if (!vblist) {
snmp_log(LOG_WARNING,
"send_trap: called with NULL v2 information\n");
return -1;
}
template_v2pdu = snmp_pdu_create(SNMP_MSG_TRAP2);
if (!template_v2pdu) {
snmp_log(LOG_WARNING,
"send_trap: failed to construct v2 template PDU\n");
snmp_free_varbind(vblist);
return -1;
}
/*
* Check the varbind list we've been given.
* If it starts with a 'sysUptime.0' varbind, then use that.
* Otherwise, prepend a suitable 'sysUptime.0' varbind.
*/
if (!snmp_oid_compare( vblist->name, vblist->name_length,
sysuptime_oid, sysuptime_oid_len )) {
template_v2pdu->variables = vblist;
trap_vb = vblist->next_variable;
} else {
uptime = netsnmp_get_agent_uptime();
var = NULL;
snmp_varlist_add_variable( &var,
sysuptime_oid, sysuptime_oid_len,
ASN_TIMETICKS, (u_char*)&uptime, sizeof(uptime));
if (!var) {
snmp_log(LOG_WARNING,
"send_trap: failed to insert sysUptime varbind\n");
snmp_free_pdu(template_v2pdu);
snmp_free_varbind(vblist);
return -1;
}
template_v2pdu->variables = var;
var->next_variable = vblist;
trap_vb = vblist;
}
/*
* 'trap_vb' should point to the snmpTrapOID.0 varbind,
* identifying the requested trap. If not then bomb out.
* If it's a 'standard' trap, then we need to append an
* snmpEnterprise varbind (if there isn't already one).
*/
if (!trap_vb ||
snmp_oid_compare(trap_vb->name, trap_vb->name_length,
snmptrap_oid, snmptrap_oid_len)) {
snmp_log(LOG_WARNING,
"send_trap: no v2 trapOID varbind provided\n");
snmp_free_pdu(template_v2pdu);
return -1;
}
if (!snmp_oid_compare(vblist->val.objid, OID_LENGTH(trap_prefix),
trap_prefix, OID_LENGTH(trap_prefix))) {
var = find_varbind_in_list( template_v2pdu->variables,
snmptrapenterprise_oid,
snmptrapenterprise_oid_len);
if (!var &&
!snmp_varlist_add_variable( &(template_v2pdu->variables),
snmptrapenterprise_oid, snmptrapenterprise_oid_len,
ASN_OBJECT_ID,
enterprise, enterprise_length*sizeof(oid))) {
snmp_log(LOG_WARNING,
"send_trap: failed to add snmpEnterprise to v2 trap\n");
snmp_free_pdu(template_v2pdu);
return -1;
}
}
/*
* If everything's OK, convert the v2 template into an SNMPv1 trap PDU.
*/
template_v1pdu = convert_v2pdu_to_v1( template_v2pdu );
if (!template_v1pdu) {
snmp_log(LOG_WARNING,
"send_trap: failed to convert v2->v1 template PDU\n");
}
} else {
/*
* Construct the SNMPv1 trap PDU....
*/
template_v1pdu = snmp_pdu_create(SNMP_MSG_TRAP);
if (!template_v1pdu) {
snmp_log(LOG_WARNING,
"send_trap: failed to construct v1 template PDU\n");
snmp_free_varbind(vblist);
return -1;
}
template_v1pdu->trap_type = trap;
template_v1pdu->specific_type = specific;
template_v1pdu->time = netsnmp_get_agent_uptime();
if (snmp_clone_mem((void **) &template_v1pdu->enterprise,
enterprise, enterprise_length * sizeof(oid))) {
snmp_log(LOG_WARNING,
"send_trap: failed to set v1 enterprise OID\n");
snmp_free_varbind(vblist);
snmp_free_pdu(template_v1pdu);
return -1;
}
template_v1pdu->enterprise_length = enterprise_length;
template_v1pdu->flags |= UCD_MSG_FLAG_FORCE_PDU_COPY;
template_v1pdu->variables = vblist;
/*
* ... and convert it into an SNMPv2-style notification PDU.
*/
template_v2pdu = convert_v1pdu_to_v2( template_v1pdu );
if (!template_v2pdu) {
snmp_log(LOG_WARNING,
"send_trap: failed to convert v1->v2 template PDU\n");
}
}
/*
* Check whether we're ignoring authFail traps
*/
if (template_v1pdu) {
if (template_v1pdu->trap_type == SNMP_TRAP_AUTHFAIL &&
snmp_enableauthentraps == SNMP_AUTHENTICATED_TRAPS_DISABLED) {
snmp_free_pdu(template_v1pdu);
snmp_free_pdu(template_v2pdu);
return 0;
}
/*
* Ensure that the v1 trap PDU includes the local IP address
*/
pdu_in_addr_t = (in_addr_t *) template_v1pdu->agent_addr;
v1trapaddress = netsnmp_ds_get_string(NETSNMP_DS_APPLICATION_ID,
NETSNMP_DS_AGENT_TRAP_ADDR);
if (v1trapaddress != NULL) {
/* "v1trapaddress" was specified in config, try to resolve it */
res = netsnmp_gethostbyname_v4(v1trapaddress, pdu_in_addr_t);
}
if (v1trapaddress == NULL || res < 0) {
/* "v1trapaddress" was not specified in config or the resolution failed,
* try any local address */
*pdu_in_addr_t = get_myaddr();
}
}
if (template_v2pdu) {
/* A context name was provided, so copy it and its length to the v2 pdu
* template. */
if (context != NULL)
{
template_v2pdu->contextName = strdup(context);
template_v2pdu->contextNameLen = strlen(context);
}
}
/*
* Now loop through the list of trap sinks
* and call the trap callback routines,
* providing an appropriately formatted PDU in each case
*/
for (sink = sinks; sink; sink = sink->next) {
#ifndef NETSNMP_DISABLE_SNMPV1
if (sink->version == SNMP_VERSION_1) {
if (template_v1pdu) {
send_trap_to_sess(sink->sesp, template_v1pdu);
}
} else {
#endif
if (template_v2pdu) {
template_v2pdu->command = sink->pdutype;
send_trap_to_sess(sink->sesp, template_v2pdu);
}
#ifndef NETSNMP_DISABLE_SNMPV1
}
#endif
}
if (template_v1pdu)
snmp_call_callbacks(SNMP_CALLBACK_APPLICATION,
SNMPD_CALLBACK_SEND_TRAP1, template_v1pdu);
if (template_v2pdu)
snmp_call_callbacks(SNMP_CALLBACK_APPLICATION,
SNMPD_CALLBACK_SEND_TRAP2, template_v2pdu);
snmp_free_pdu(template_v1pdu);
snmp_free_pdu(template_v2pdu);
return 0;
}
void
send_enterprise_trap_vars(int trap,
int specific,
const oid * enterprise, int enterprise_length,
netsnmp_variable_list * vars)
{
netsnmp_send_traps(trap, specific,
enterprise, enterprise_length,
vars, NULL, 0);
return;
}
/**
* Captures responses or the lack there of from INFORMs that were sent
* 1) a response is received from an INFORM
* 2) one isn't received and the retries/timeouts have failed
*/
int
handle_inform_response(int op, netsnmp_session * session,
int reqid, netsnmp_pdu *pdu,
void *magic)
{
/* XXX: possibly stats update */
switch (op) {
case NETSNMP_CALLBACK_OP_RECEIVED_MESSAGE:
snmp_increment_statistic(STAT_SNMPINPKTS);
DEBUGMSGTL(("trap", "received the inform response for reqid=%d\n",
reqid));
break;
case NETSNMP_CALLBACK_OP_TIMED_OUT:
DEBUGMSGTL(("trap",
"received a timeout sending an inform for reqid=%d\n",
reqid));
break;
case NETSNMP_CALLBACK_OP_SEND_FAILED:
DEBUGMSGTL(("trap",
"failed to send an inform for reqid=%d\n",
reqid));
break;
default:
DEBUGMSGTL(("trap", "received op=%d for reqid=%d when trying to send an inform\n", op, reqid));
}
return 1;
}
/*
* send_trap_to_sess: sends a trap to a session but assumes that the
* pdu is constructed correctly for the session type.
*/
void
send_trap_to_sess(netsnmp_session * sess, netsnmp_pdu *template_pdu)
{
netsnmp_pdu *pdu;
int result;
if (!sess || !template_pdu)
return;
DEBUGMSGTL(("trap", "sending trap type=%d, version=%ld\n",
template_pdu->command, sess->version));
#ifndef NETSNMP_DISABLE_SNMPV1
if (sess->version == SNMP_VERSION_1 &&
(template_pdu->command != SNMP_MSG_TRAP))
return; /* Skip v1 sinks for v2 only traps */
if (sess->version != SNMP_VERSION_1 &&
(template_pdu->command == SNMP_MSG_TRAP))
return; /* Skip v2+ sinks for v1 only traps */
#endif
template_pdu->version = sess->version;
pdu = snmp_clone_pdu(template_pdu);
pdu->sessid = sess->sessid; /* AgentX only ? */
if ( template_pdu->command == SNMP_MSG_INFORM
#ifdef USING_AGENTX_PROTOCOL_MODULE
|| template_pdu->command == AGENTX_MSG_NOTIFY
#endif
) {
result =
snmp_async_send(sess, pdu, &handle_inform_response, NULL);
} else {
if ((sess->version == SNMP_VERSION_3) &&
(pdu->command == SNMP_MSG_TRAP2) &&
(sess->securityEngineIDLen == 0)) {
u_char tmp[SPRINT_MAX_LEN];
int len = snmpv3_get_engineID(tmp, sizeof(tmp));
memdup(&pdu->securityEngineID, tmp, len);
pdu->securityEngineIDLen = len;
}
result = snmp_send(sess, pdu);
}
if (result == 0) {
snmp_sess_perror("snmpd: send_trap", sess);
snmp_free_pdu(pdu);
} else {
snmp_increment_statistic(STAT_SNMPOUTTRAPS);
snmp_increment_statistic(STAT_SNMPOUTPKTS);
}
}
void
send_trap_vars(int trap, int specific, netsnmp_variable_list * vars)
{
if (trap == SNMP_TRAP_ENTERPRISESPECIFIC)
send_enterprise_trap_vars(trap, specific, objid_enterprisetrap,
OID_LENGTH(objid_enterprisetrap), vars);
else
send_enterprise_trap_vars(trap, specific, trap_version_id,
OID_LENGTH(trap_version_id), vars);
}
#ifndef NETSNMP_FEATURE_REMOVE_TRAP_VARS_WITH_CONTEXT
/* Send a trap under a context */
void send_trap_vars_with_context(int trap, int specific,
netsnmp_variable_list *vars, const char *context)
{
if (trap == SNMP_TRAP_ENTERPRISESPECIFIC)
netsnmp_send_traps(trap, specific, objid_enterprisetrap,
OID_LENGTH(objid_enterprisetrap), vars,
context, 0);
else
netsnmp_send_traps(trap, specific, trap_version_id,
OID_LENGTH(trap_version_id), vars,
context, 0);
}
#endif /* NETSNMP_FEATURE_REMOVE_TRAP_VARS_WITH_CONTEXT */
/**
* Sends an SNMPv1 trap (or the SNMPv2 equivalent) to the list of
* configured trap destinations (or "sinks"), using the provided
* values for the generic trap type and specific trap value.
*
* This function eventually calls send_enterprise_trap_vars. If the
* trap type is not set to SNMP_TRAP_ENTERPRISESPECIFIC the enterprise
* and enterprise_length paramater is set to the pre defined NETSNMP_SYSTEM_MIB
* oid and length respectively. If the trap type is set to
* SNMP_TRAP_ENTERPRISESPECIFIC the enterprise and enterprise_length
* parameters are set to the pre-defined NETSNMP_NOTIFICATION_MIB oid and length
* respectively.
*
* @param trap is the generic trap type.
*
* @param specific is the specific trap value.
*
* @return void
*
* @see send_enterprise_trap_vars
* @see send_v2trap
*/
void
send_easy_trap(int trap, int specific)
{
send_trap_vars(trap, specific, NULL);
}
/**
* Uses the supplied list of variable bindings to form an SNMPv2 trap,
* which is sent to SNMPv2-capable sinks on the configured list.
* An equivalent INFORM is sent to the configured list of inform sinks.
* Sinks that can only handle SNMPv1 traps are skipped.
*
* This function eventually calls send_enterprise_trap_vars. If the
* trap type is not set to SNMP_TRAP_ENTERPRISESPECIFIC the enterprise
* and enterprise_length paramater is set to the pre defined NETSNMP_SYSTEM_MIB
* oid and length respectively. If the trap type is set to
* SNMP_TRAP_ENTERPRISESPECIFIC the enterprise and enterprise_length
* parameters are set to the pre-defined NETSNMP_NOTIFICATION_MIB oid and length
* respectively.
*
* @param vars is used to supply list of variable bindings to form an SNMPv2
* trap.
*
* @return void
*
* @see send_easy_trap
* @see send_enterprise_trap_vars
*/
void
send_v2trap(netsnmp_variable_list * vars)
{
send_trap_vars(-1, -1, vars);
}
/**
* Similar to send_v2trap(), with the added ability to specify a context. If
* the last parameter is NULL, then this call is equivalent to send_v2trap().
*
* @param vars is used to supply the list of variable bindings for the trap.
*
* @param context is used to specify the context of the trap.
*
* @return void
*
* @see send_v2trap
*/
#ifndef NETSNMP_FEATURE_REMOVE_SEND_V3TRAP
void send_v3trap(netsnmp_variable_list *vars, const char *context)
{
netsnmp_send_traps(-1, -1,
trap_version_id, OID_LENGTH(trap_version_id),
vars, context, 0);
}
#endif /* NETSNMP_FEATURE_REMOVE_SEND_V3TRAP */
#ifndef NETSNMP_FEATURE_REMOVE_SEND_TRAP_PDU
void
send_trap_pdu(netsnmp_pdu *pdu)
{
send_trap_vars(-1, -1, pdu->variables);
}
#endif /* NETSNMP_FEATURE_REMOVE_SEND_TRAP_PDU */
/*******************
*
* Config file handling
*
*******************/
void
snmpd_parse_config_authtrap(const char *token, char *cptr)
{
int i;
i = atoi(cptr);
if (i == 0) {
if (strcmp(cptr, "enable") == 0) {
i = SNMP_AUTHENTICATED_TRAPS_ENABLED;
} else if (strcmp(cptr, "disable") == 0) {
i = SNMP_AUTHENTICATED_TRAPS_DISABLED;
}
}
if (i < 1 || i > 2) {
config_perror("authtrapenable must be 1 or 2");
} else {
if (strcmp(token, "pauthtrapenable") == 0) {
if (snmp_enableauthentrapsset < 0) {
/*
* This is bogus (and shouldn't happen anyway) -- the value
* of snmpEnableAuthenTraps.0 is already configured
* read-only.
*/
snmp_log(LOG_WARNING,
"ignoring attempted override of read-only snmpEnableAuthenTraps.0\n");
return;
} else {
snmp_enableauthentrapsset++;
}
} else {
if (snmp_enableauthentrapsset > 0) {
/*
* This is bogus (and shouldn't happen anyway) -- we already
* read a persistent value of snmpEnableAuthenTraps.0, which
* we should ignore in favour of this one.
*/
snmp_log(LOG_WARNING,
"ignoring attempted override of read-only snmpEnableAuthenTraps.0\n");
/*
* Fall through and copy in this value.
*/
}
snmp_enableauthentrapsset = -1;
}
snmp_enableauthentraps = i;
}
}
#ifndef NETSNMP_DISABLE_SNMPV1
void
snmpd_parse_config_trapsink(const char *token, char *cptr)
{
char *sp, *cp, *pp = NULL;
char *st;
if (!snmp_trapcommunity)
snmp_trapcommunity = strdup("public");
sp = strtok_r(cptr, " \t\n", &st);
cp = strtok_r(NULL, " \t\n", &st);
if (cp)
pp = strtok_r(NULL, " \t\n", &st);
if (pp)
config_pwarn("The separate port argument to trapsink is deprecated");
if (create_v1_trap_session(sp, pp, cp ? cp : snmp_trapcommunity) == 0) {
netsnmp_config_error("cannot create trapsink: %s", cptr);
}
}
#endif
#ifndef NETSNMP_DISABLE_SNMPV2C
void
snmpd_parse_config_trap2sink(const char *word, char *cptr)
{
char *st, *sp, *cp, *pp = NULL;
if (!snmp_trapcommunity)
snmp_trapcommunity = strdup("public");
sp = strtok_r(cptr, " \t\n", &st);
cp = strtok_r(NULL, " \t\n", &st);
if (cp)
pp = strtok_r(NULL, " \t\n", &st);
if (pp)
config_pwarn("The separate port argument to trapsink2 is deprecated");
if (create_v2_trap_session(sp, pp, cp ? cp : snmp_trapcommunity) == 0) {
netsnmp_config_error("cannot create trap2sink: %s", cptr);
}
}
void
snmpd_parse_config_informsink(const char *word, char *cptr)
{
char *st, *sp, *cp, *pp = NULL;
if (!snmp_trapcommunity)
snmp_trapcommunity = strdup("public");
sp = strtok_r(cptr, " \t\n", &st);
cp = strtok_r(NULL, " \t\n", &st);
if (cp)
pp = strtok_r(NULL, " \t\n", &st);
if (pp)
config_pwarn("The separate port argument to informsink is deprecated");
if (create_v2_inform_session(sp, pp, cp ? cp : snmp_trapcommunity) == 0) {
netsnmp_config_error("cannot create informsink: %s", cptr);
}
}
#endif
/*
* this must be standardized somewhere, right?
*/
#define MAX_ARGS 128
static int traptype;
static void
trapOptProc(int argc, char *const *argv, int opt)
{
switch (opt) {
case 'C':
while (*optarg) {
switch (*optarg++) {
case 'i':
traptype = SNMP_MSG_INFORM;
break;
default:
config_perror("unknown argument passed to -C");
break;
}
}
break;
}
}
void
snmpd_parse_config_trapsess(const char *word, char *cptr)
{
char *argv[MAX_ARGS], *cp = cptr;
int argn, rc;
netsnmp_session session, *ss;
netsnmp_transport *transport;
size_t len;
/*
* inform or trap? default to trap
*/
traptype = SNMP_MSG_TRAP2;
/*
* create the argv[] like array
*/
argv[0] = strdup("snmpd-trapsess"); /* bogus entry for getopt() */
for (argn = 1; cp && argn < MAX_ARGS; argn++) {
char tmp[SPRINT_MAX_LEN];
cp = copy_nword(cp, tmp, SPRINT_MAX_LEN);
argv[argn] = strdup(tmp);
}
netsnmp_parse_args(argn, argv, &session, "C:", trapOptProc,
NETSNMP_PARSE_ARGS_NOLOGGING |
NETSNMP_PARSE_ARGS_NOZERO);
transport = netsnmp_transport_open_client("snmptrap", session.peername);
if (transport == NULL) {
config_perror("snmpd: failed to parse this line.");
return;
}
if ((rc = netsnmp_sess_config_and_open_transport(&session, transport))
!= SNMPERR_SUCCESS) {
session.s_snmp_errno = rc;
session.s_errno = 0;
return;
}
ss = snmp_add(&session, transport, NULL, NULL);
for (; argn > 0; argn--) {
free(argv[argn - 1]);
}
if (!ss) {
config_perror
("snmpd: failed to parse this line or the remote trap receiver is down. Possible cause:");
snmp_sess_perror("snmpd: snmpd_parse_config_trapsess()", &session);
return;
}
/*
* If this is an SNMPv3 TRAP session, then the agent is
* the authoritative engine, so set the engineID accordingly
*/
if (ss->version == SNMP_VERSION_3 &&
traptype != SNMP_MSG_INFORM &&
ss->securityEngineIDLen == 0) {
u_char tmp[SPRINT_MAX_LEN];
len = snmpv3_get_engineID( tmp, sizeof(tmp));
memdup(&ss->securityEngineID, tmp, len);
ss->securityEngineIDLen = len;
}
#ifndef NETSNMP_DISABLE_SNMPV1
if (ss->version == SNMP_VERSION_1)
traptype = SNMP_MSG_TRAP;
#endif
add_trap_session(ss, traptype, (traptype == SNMP_MSG_INFORM), ss->version);
}
#if !defined(NETSNMP_DISABLE_SNMPV1) || !defined(NETSNMP_DISABLE_SNMPV2C)
void
snmpd_parse_config_trapcommunity(const char *word, char *cptr)
{
if (snmp_trapcommunity != NULL) {
free(snmp_trapcommunity);
}
snmp_trapcommunity = (char *) malloc(strlen(cptr) + 1);
if (snmp_trapcommunity != NULL) {
copy_nword(cptr, snmp_trapcommunity, strlen(cptr) + 1);
}
}
void
snmpd_free_trapcommunity(void)
{
if (snmp_trapcommunity) {
free(snmp_trapcommunity);
snmp_trapcommunity = NULL;
}
}
#endif
/** @} */