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/******************************************************************
Copyright 1989, 1991, 1992 by Carnegie Mellon University
All Rights Reserved
Permission to use, copy, modify, and distribute this software and its
documentation for any purpose and without fee is hereby granted,
provided that the above copyright notice appear in all copies and that
both that copyright notice and this permission notice appear in
supporting documentation, and that the name of CMU not be
used in advertising or publicity pertaining to distribution of the
software without specific, written prior permission.
CMU DISCLAIMS ALL WARRANTIES WITH REGARD TO THIS SOFTWARE, INCLUDING
ALL IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS, IN NO EVENT SHALL
CMU BE LIABLE FOR ANY SPECIAL, INDIRECT OR CONSEQUENTIAL DAMAGES OR
ANY DAMAGES WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS,
WHETHER IN AN ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION,
ARISING OUT OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS
SOFTWARE.
******************************************************************/
/*
* snmp_api.c - API for access to snmp.
*/
#include <config.h>
#include <stdio.h>
#include <ctype.h>
#if HAVE_STDLIB_H
#include <stdlib.h>
#endif
#if HAVE_STRING_H
#include <string.h>
#else
#include <strings.h>
#endif
#if HAVE_UNISTD_H
#include <unistd.h>
#endif
#include <sys/types.h>
#if HAVE_SYS_PARAM_H
#include <sys/param.h>
#endif
#if TIME_WITH_SYS_TIME
# ifdef WIN32
# include <sys/timeb.h>
# else
# include <sys/time.h>
# endif
# include <time.h>
#else
# if HAVE_SYS_TIME_H
# include <sys/time.h>
# else
# include <time.h>
# endif
#endif
#if HAVE_NETINET_IN_H
#include <netinet/in.h>
#endif
#if HAVE_ARPA_INET_H
#include <arpa/inet.h>
#endif
#if HAVE_SYS_SELECT_H
#include <sys/select.h>
#endif
#if HAVE_IO_H
#include <io.h>
#endif
#if HAVE_WINSOCK_H
#include <winsock.h>
#endif
#if HAVE_SYS_SOCKET_H
#include <sys/socket.h>
#endif
#if HAVE_SYS_UN_H
#include <sys/un.h>
#endif
#if HAVE_NETDB_H
#include <netdb.h>
#endif
#if HAVE_NET_IF_DL_H
#include <net/if_dl.h>
#endif
#include <errno.h>
#if HAVE_LOCALE_H
#include <locale.h>
#endif
#if HAVE_DMALLOC_H
#include <dmalloc.h>
#endif
#include "asn1.h"
#include "snmp.h"
#define SNMP_NEED_REQUEST_LIST
#include "snmp_api.h"
#include "snmp_client.h"
#include "snmp_impl.h"
#include "parse.h"
#include "mib.h"
#include "system.h"
#include "int64.h"
#include "snmpv3.h"
#include "read_config.h"
#include "snmp_debug.h"
#include "callback.h"
#include "snmp_secmod.h"
#ifdef SNMP_SECMOD_USM
#include "snmpusm.h"
#endif
#ifdef SNMP_SECMOD_KSM
#include "snmpksm.h"
#endif
#include "tools.h"
#include "keytools.h"
#include "lcd_time.h"
#include "snmp_alarm.h"
#include "snmp_logging.h"
#include "default_store.h"
#include "mt_support.h"
#include "snmp-tc.h"
#include "snmp_parse_args.h"
#include "snmp_transport.h"
static void _init_snmp (void);
#include "transform_oids.h"
#ifndef timercmp
#define timercmp(tvp, uvp, cmp) \
/* CSTYLED */ \
((tvp)->tv_sec cmp (uvp)->tv_sec || \
((tvp)->tv_sec == (uvp)->tv_sec && \
/* CSTYLED */ \
(tvp)->tv_usec cmp (uvp)->tv_usec))
#endif
#ifndef timerclear
#define timerclear(tvp) (tvp)->tv_sec = (tvp)->tv_usec = 0
#endif
/*
* Globals.
*/
#define MAX_PACKET_LENGTH (0x7fffffff)
#ifndef SNMP_STREAM_QUEUE_LEN
#define SNMP_STREAM_QUEUE_LEN 5
#endif
#ifndef BSD4_3
#define BSD4_2
#endif
#ifndef FD_SET
typedef long fd_mask;
#define NFDBITS (sizeof(fd_mask) * NBBY) /* bits per mask */
#define FD_SET(n, p) ((p)->fds_bits[(n)/NFDBITS] |= (1 << ((n) % NFDBITS)))
#define FD_CLR(n, p) ((p)->fds_bits[(n)/NFDBITS] &= ~(1 << ((n) % NFDBITS)))
#define FD_ISSET(n, p) ((p)->fds_bits[(n)/NFDBITS] & (1 << ((n) % NFDBITS)))
#define FD_ZERO(p) memset((p), 0, sizeof(*(p)))
#endif
static oid default_enterprise[] = {1, 3, 6, 1, 4, 1, 3, 1, 1};
/* enterprises.cmu.systems.cmuSNMP */
#define DEFAULT_COMMUNITY "public"
#define DEFAULT_RETRIES 5
#define DEFAULT_TIMEOUT 1000000L
#define DEFAULT_REMPORT SNMP_PORT
#define DEFAULT_ENTERPRISE default_enterprise
#define DEFAULT_TIME 0
/*
* Internal information about the state of the snmp session.
*/
struct snmp_internal_session {
struct request_list *requests;/* Info about outstanding requests */
struct request_list *requestsEnd; /* ptr to end of list */
int (*hook_pre) (struct snmp_session *, struct _snmp_transport *,
void *, int);
int (*hook_parse)(struct snmp_session *, struct snmp_pdu *,
u_char *, size_t);
int (*hook_post) (struct snmp_session *, struct snmp_pdu*, int);
int (*hook_build)(struct snmp_session *, struct snmp_pdu *,
u_char *, size_t *);
int (*hook_realloc_build)(struct snmp_session *, struct snmp_pdu *,
u_char **, size_t *, size_t *);
int (*check_packet) (u_char *, size_t);
u_char *packet;
size_t packet_len, packet_size;
};
/*
* The list of active/open sessions.
*/
struct session_list {
struct session_list *next;
struct snmp_session *session;
snmp_transport *transport;
struct snmp_internal_session *internal;
};
static const char *api_errors[-SNMPERR_MAX+1] = {
"No error", /* SNMPERR_SUCCESS */
"Generic error", /* SNMPERR_GENERR */
"Invalid local port", /* SNMPERR_BAD_LOCPORT */
"Unknown host", /* SNMPERR_BAD_ADDRESS */
"Unknown session", /* SNMPERR_BAD_SESSION */
"Too long", /* SNMPERR_TOO_LONG */
"No socket", /* SNMPERR_NO_SOCKET */
"Cannot send V2 PDU on V1 session", /* SNMPERR_V2_IN_V1 */
"Cannot send V1 PDU on V2 session", /* SNMPERR_V1_IN_V2 */
"Bad value for non-repeaters", /* SNMPERR_BAD_REPEATERS */
"Bad value for max-repetitions", /* SNMPERR_BAD_REPETITIONS */
"Error building ASN.1 representation", /* SNMPERR_BAD_ASN1_BUILD */
"Failure in sendto", /* SNMPERR_BAD_SENDTO */
"Bad parse of ASN.1 type", /* SNMPERR_BAD_PARSE */
"Bad version specified", /* SNMPERR_BAD_VERSION */
"Bad source party specified", /* SNMPERR_BAD_SRC_PARTY */
"Bad destination party specified", /* SNMPERR_BAD_DST_PARTY */
"Bad context specified", /* SNMPERR_BAD_CONTEXT */
"Bad community specified", /* SNMPERR_BAD_COMMUNITY */
"Cannot send noAuth/desPriv", /* SNMPERR_NOAUTH_DESPRIV */
"Bad ACL definition", /* SNMPERR_BAD_ACL */
"Bad Party definition", /* SNMPERR_BAD_PARTY */
"Session abort failure", /* SNMPERR_ABORT */
"Unknown PDU type", /* SNMPERR_UNKNOWN_PDU */
"Timeout", /* SNMPERR_TIMEOUT */
"Failure in recvfrom", /* SNMPERR_BAD_RECVFROM */
"Unable to determine contextEngineID", /* SNMPERR_BAD_ENG_ID */
"Unable to determine securityName", /* SNMPERR_BAD_SEC_NAME */
"Unable to determine securityLevel", /* SNMPERR_BAD_SEC_LEVEL */
"ASN.1 parse error in message", /* SNMPERR_ASN_PARSE_ERR */
"Unknown security model in message", /* SNMPERR_UNKNOWN_SEC_MODEL */
"Invalid message (e.g. msgFlags)", /* SNMPERR_INVALID_MSG */
"Unknown engine ID", /* SNMPERR_UNKNOWN_ENG_ID */
"Unknown user name", /* SNMPERR_UNKNOWN_USER_NAME */
"Unsupported security level", /* SNMPERR_UNSUPPORTED_SEC_LEVEL */
"Authentication failure", /* SNMPERR_AUTHENTICATION_FAILURE */
"Not in time window", /* SNMPERR_NOT_IN_TIME_WINDOW */
"Decryption error", /* SNMPERR_DECRYPTION_ERR */
"SCAPI general failure", /* SNMPERR_SC_GENERAL_FAILURE */
"SCAPI sub-system not configured", /* SNMPERR_SC_NOT_CONFIGURED */
"Key tools not available", /* SNMPERR_KT_NOT_AVAILABLE */
"Unknown Report message", /* SNMPERR_UNKNOWN_REPORT */
"USM generic error", /* SNMPERR_USM_GENERICERROR */
"USM unknown security name", /* SNMPERR_USM_UNKNOWNSECURITYNAME */
"USM unsupported security level", /* SNMPERR_USM_UNSUPPORTEDSECURITYLEVEL */
"USM encryption error", /* SNMPERR_USM_ENCRYPTIONERROR */
"USM authentication failure", /* SNMPERR_USM_AUTHENTICATIONFAILURE */
"USM parse error", /* SNMPERR_USM_PARSEERROR */
"USM unknown engineID", /* SNMPERR_USM_UNKNOWNENGINEID */
"USM not in time window", /* SNMPERR_USM_NOTINTIMEWINDOW */
"USM decryption error", /* SNMPERR_USM_DECRYPTIONERROR */
"MIB not initialized", /* SNMPERR_NOMIB */
"Value out of range", /* SNMPERR_RANGE */
"Sub-id out of range", /* SNMPERR_MAX_SUBID */
"Bad sub-id in object identifier", /* SNMPERR_BAD_SUBID */
"Object identifier too long", /* SNMPERR_LONG_OID */
"Bad value name", /* SNMPERR_BAD_NAME */
"Bad value notation", /* SNMPERR_VALUE */
"Unknown Object Identifier", /* SNMPERR_UNKNOWN_OBJID */
"No PDU in snmp_send", /* SNMPERR_NULL_PDU */
"Missing variables in PDU", /* SNMPERR_NO_VARS */
"Bad variable type", /* SNMPERR_VAR_TYPE */
"Out of memory (malloc failure)", /* SNMPERR_MALLOC */
"Kerberos related error", /* SNMPERR_KRB5 */
};
static const char * secLevelName[] = {
"BAD_SEC_LEVEL",
"noAuthNoPriv",
"authNoPriv",
"authPriv"
};
/*
* Multiple threads may changes these variables.
* Suggest using the Single API, which does not use Sessions.
*
* Reqid may need to be protected. Time will tell...
*
*/
/*MTCRITICAL_RESOURCE*/
/* use token in comments to individually protect these resources */
struct session_list *Sessions = NULL; /* MT_LIB_SESSION */
static long Reqid = 0; /* MT_LIB_REQUESTID */
static long Msgid = 0; /* MT_LIB_MESSAGEID */
static long Sessid = 0; /* MT_LIB_SESSIONID */
static long Transid = 0; /* MT_LIB_TRANSID */
int snmp_errno = 0;
/*END MTCRITICAL_RESOURCE*/
/*
* global error detail storage
*/
static char snmp_detail[192];
static int snmp_detail_f = 0;
/*
* Prototypes.
*/
int snmp_build (u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_session *pss, struct snmp_pdu *pdu);
static int snmp_parse (void *, struct snmp_session *, struct snmp_pdu *, u_char *, size_t);
static void snmpv3_calc_msg_flags (int, int, u_char *);
static int snmpv3_verify_msg (struct request_list *, struct snmp_pdu *);
static int snmpv3_build_probe_pdu (struct snmp_pdu **);
static int snmpv3_build (u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_session *session, struct snmp_pdu *pdu);
static int snmp_parse_version (u_char *, size_t);
static int snmp_resend_request (struct session_list *slp,
struct request_list *rp,
int incr_retries);
static void register_default_handlers(void);
static struct session_list *snmp_sess_copy( struct snmp_session *pss);
int snmp_get_errno(void);
void snmp_synch_reset(struct snmp_session * notused);
void snmp_synch_setup(struct snmp_session * notused);
#ifndef HAVE_STRERROR
const char *strerror(int err)
{
extern const char *sys_errlist[];
extern int sys_nerr;
if (err < 0 || err >= sys_nerr) return "Unknown error";
return sys_errlist[err];
}
#endif
#define DEBUGPRINTPDUTYPE(token, type) \
switch(type) { \
case SNMP_MSG_GET: \
DEBUGDUMPSECTION(token, "PDU-GET"); \
break; \
case SNMP_MSG_GETNEXT: \
DEBUGDUMPSECTION(token, "PDU-GETNEXT"); \
break; \
case SNMP_MSG_RESPONSE: \
DEBUGDUMPSECTION(token, "PDU-RESPONSE"); \
break; \
case SNMP_MSG_SET: \
DEBUGDUMPSECTION(token, "PDU-SET"); \
break; \
case SNMP_MSG_GETBULK: \
DEBUGDUMPSECTION(token, "PDU-GETBULK"); \
break; \
case SNMP_MSG_INFORM: \
DEBUGDUMPSECTION(token, "PDU-INFORM"); \
break; \
case SNMP_MSG_TRAP2: \
DEBUGDUMPSECTION(token, "PDU-TRAP2"); \
break; \
case SNMP_MSG_REPORT: \
DEBUGDUMPSECTION(token, "PDU-REPORT"); \
break; \
default: \
DEBUGDUMPSECTION(token, "PDU-UNKNOWN"); \
break; \
}
long
snmp_get_next_reqid (void)
{
long retVal;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_REQUESTID);
retVal = 1 + Reqid; /*MTCRITICAL_RESOURCE*/
if (!retVal) retVal = 2;
Reqid = retVal;
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_REQUESTID);
return retVal;
}
long
snmp_get_next_msgid (void)
{
long retVal;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_MESSAGEID);
retVal = 1 + Msgid; /*MTCRITICAL_RESOURCE*/
if (!retVal) retVal = 2;
Msgid = retVal;
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_MESSAGEID);
return retVal;
}
long
snmp_get_next_sessid (void)
{
long retVal;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSIONID);
retVal = 1 + Sessid; /*MTCRITICAL_RESOURCE*/
if (!retVal) retVal = 2;
Sessid = retVal;
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSIONID);
return retVal;
}
long
snmp_get_next_transid (void)
{
long retVal;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_TRANSID);
retVal = 1 + Transid; /*MTCRITICAL_RESOURCE*/
if (!retVal) retVal = 2;
Transid = retVal;
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_TRANSID);
return retVal;
}
void
snmp_perror(const char *prog_string)
{
const char *str;
int xerr;
xerr = snmp_errno; /*MTCRITICAL_RESOURCE*/
str = snmp_api_errstring(xerr);
snmp_log(LOG_ERR,"%s: %s\n",prog_string, str);
}
void
snmp_set_detail(const char *detail_string)
{
if (detail_string != NULL) {
strncpy((char *)snmp_detail, detail_string, sizeof(snmp_detail));
snmp_detail[sizeof(snmp_detail)-1] = '\0';
snmp_detail_f = 1;
}
}
/* returns pointer to static data */
/* results not guaranteed in multi-threaded use */
const char *
snmp_api_errstring(int snmp_errnumber)
{
const char *msg = "";
static char msg_buf [256];
if (snmp_errnumber >= SNMPERR_MAX && snmp_errnumber <= SNMPERR_GENERR){
msg = api_errors[-snmp_errnumber];
} else if (snmp_errnumber != SNMPERR_SUCCESS) {
msg = "Unknown Error";
}
if (snmp_detail_f) {
sprintf (msg_buf, "%s (%s)", msg, snmp_detail);
snmp_detail_f = 0;
}
else
strcpy(msg_buf,msg);
return (msg_buf);
}
/*
* snmp_error - return error data
* Inputs : address of errno, address of snmp_errno, address of string
* Caller must free the string returned after use.
*/
void
snmp_error(struct snmp_session *psess,
int *p_errno,
int *p_snmp_errno,
char **p_str)
{
char buf[SPRINT_MAX_LEN];
int snmp_errnumber;
if (p_errno) *p_errno = psess->s_errno;
if (p_snmp_errno) *p_snmp_errno = psess->s_snmp_errno;
if (p_str == NULL) return;
strcpy(buf, "");
snmp_errnumber = psess->s_snmp_errno;
if (snmp_errnumber >= SNMPERR_MAX && snmp_errnumber <= SNMPERR_GENERR){
strcpy(buf, api_errors[-snmp_errnumber]);
} else {
if (snmp_errnumber)
sprintf(buf, "Unknown Error %d", snmp_errnumber);
}
/* append a useful system errno interpretation. */
if (psess->s_errno)
sprintf (&buf[strlen(buf)], " (%s)", strerror(psess->s_errno));
*p_str = strdup(buf);
}
/*
* snmp_sess_error - same as snmp_error for single session API use.
*/
void
snmp_sess_error(void *sessp,
int *p_errno,
int *p_snmp_errno,
char **p_str)
{
struct session_list *slp = (struct session_list*)sessp;
if ((slp) && (slp->session))
snmp_error(slp->session, p_errno, p_snmp_errno, p_str);
}
/* snmp_sess_perror(): print a error stored in a session pointer */
void
snmp_sess_perror(const char *prog_string, struct snmp_session *ss) {
char *err;
snmp_error(ss, NULL, NULL, &err);
snmp_log(LOG_ERR, "%s: %s\n", prog_string, err);
free(err);
}
/*
* Primordial SNMP library initialization.
* Initializes mutex locks.
* Invokes minimum required initialization for displaying MIB objects.
* Gets initial request ID for all transactions,
* and finds which port SNMP over UDP uses.
* SNMP over AppleTalk is not currently supported.
*
* Warning: no debug messages here.
*/
static void
_init_snmp (void)
{
#ifdef HAVE_GETSERVBYNAME
struct servent *servp;
#endif
struct timeval tv;
long tmpReqid, tmpMsgid;
u_short s_port = SNMP_PORT;
if (Reqid) return;
Reqid = 1; /* quick set to avoid multiple inits */
snmp_res_init(); /* initialize the mt locking structures */
init_mib_internals();
snmp_tdomain_init();
gettimeofday(&tv,(struct timezone *)0);
/*Now = tv;*/
/* get pseudo-random values for request ID and message ID */
/* don't allow zero value to repeat init */
#ifdef SVR4
srand48(tv.tv_sec ^ tv.tv_usec);
tmpReqid = lrand48();
tmpMsgid = lrand48();
#else
srandom(tv.tv_sec ^ tv.tv_usec);
tmpReqid = random();
tmpMsgid = random();
#endif
if (tmpReqid == 0) tmpReqid = 1;
if (tmpMsgid == 0) tmpMsgid = 1;
Reqid = tmpReqid;
Msgid = tmpMsgid;
#ifdef HAVE_GETSERVBYNAME
servp = getservbyname("snmp", "udp");
if (servp) {
/* store it in host byte order */
s_port = ntohs(servp->s_port);
}
#endif
ds_set_int(DS_LIBRARY_ID, DS_LIB_DEFAULT_PORT, s_port);
#ifdef USE_REVERSE_ASNENCODING
ds_set_boolean(DS_LIBRARY_ID, DS_LIB_REVERSE_ENCODE,
DEFAULT_ASNENCODING_DIRECTION);
#endif
}
/*
* Initializes the session structure.
* May perform one time minimal library initialization.
* No MIB file processing is done via this call.
*/
void
snmp_sess_init(struct snmp_session *session)
{
_init_snmp();
/* initialize session to default values */
memset(session, 0, sizeof(struct snmp_session));
session->remote_port = SNMP_DEFAULT_REMPORT;
session->timeout = SNMP_DEFAULT_TIMEOUT;
session->retries = SNMP_DEFAULT_RETRIES;
session->version = SNMP_DEFAULT_VERSION;
session->securityModel = SNMP_DEFAULT_SECMODEL;
session->rcvMsgMaxSize = SNMP_MAX_MSG_SIZE;
}
static void
register_default_handlers(void) {
ds_register_config(ASN_BOOLEAN, "snmp","dumpPacket",
DS_LIBRARY_ID, DS_LIB_DUMP_PACKET);
ds_register_config(ASN_BOOLEAN, "snmp","reverseEncodeBER",
DS_LIBRARY_ID, DS_LIB_REVERSE_ENCODE);
ds_register_config(ASN_INTEGER, "snmp","defaultPort",
DS_LIBRARY_ID, DS_LIB_DEFAULT_PORT);
ds_register_config(ASN_OCTET_STR, "snmp","defCommunity",
DS_LIBRARY_ID, DS_LIB_COMMUNITY);
ds_register_premib(ASN_BOOLEAN, "snmp", "noTokenWarnings",
DS_LIBRARY_ID, DS_LIB_NO_TOKEN_WARNINGS);
ds_register_config(ASN_BOOLEAN, "snmp","noRangeCheck",
DS_LIBRARY_ID, DS_LIB_DONT_CHECK_RANGE );
}
/*******************************************************************-o-******
* init_snmp
*
* Parameters:
* *type Label for the config file "type" used by calling entity.
*
* Call appropriately the functions to do config file loading and
* mib module parsing in the correct order.
*/
void
init_snmp(const char *type)
{
static int done_init = 0; /* To prevent double init's. */
if (done_init) {
return;
}
done_init = 1;
/* make the type available everywhere else */
if (type && !ds_get_string(DS_LIBRARY_ID, DS_LIB_APPTYPE))
ds_set_string(DS_LIBRARY_ID, DS_LIB_APPTYPE, type);
_init_snmp();
/* set our current locale properly to initialize isprint() type functions */
#ifdef HAVE_SETLOCALE
setlocale(LC_CTYPE, "");
#endif
snmp_debug_init(); /* should be done first, to turn on debugging ASAP */
init_callbacks();
init_snmp_logging();
snmp_init_statistics();
register_mib_handlers();
register_default_handlers();
init_snmpv3(type);
init_snmp_alarm();
read_premib_configs();
init_mib();
read_configs();
} /* end init_snmp() */
void
snmp_store(const char *type) {
DEBUGMSGTL(("snmp_store","storing stuff...\n"));
snmp_save_persistent(type);
snmp_call_callbacks(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_STORE_DATA, NULL);
snmp_clean_persistent(type);
}
/* snmp_shutdown(const char *type):
Parameters:
*type Label for the config file "type" used by calling entity.
Does the appropriate shutdown calls for the library, saving
persistent data, clean up, etc...
*/
void
snmp_shutdown(const char *type) {
snmp_store(type);
snmp_call_callbacks(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_SHUTDOWN, NULL);
snmp_close_sessions();
shutdown_mib();
unregister_all_config_handlers();
ds_shutdown();
}
/*
* Sets up the session with the snmp_session information provided
* by the user. Then opens and binds the necessary UDP port.
* A handle to the created session is returned (this is different than
* the pointer passed to snmp_open()). On any error, NULL is returned
* and snmp_errno is set to the appropriate error code.
*/
struct snmp_session *
snmp_open(struct snmp_session *session)
{
struct session_list *slp;
slp = (struct session_list *)snmp_sess_open(session);
if (!slp) return NULL;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
slp->next = Sessions;
Sessions = slp;
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
return (slp->session);
}
/* extended open */
struct snmp_session *snmp_open_ex (
struct snmp_session *session,
int (*fpre_parse) (struct snmp_session *, snmp_transport *, void *, int),
int (*fparse) (struct snmp_session *, struct snmp_pdu *, u_char *, size_t),
int (*fpost_parse) (struct snmp_session *, struct snmp_pdu *, int),
int (*fbuild) (struct snmp_session *, struct snmp_pdu *, u_char *, size_t *),
int (*frbuild)(struct snmp_session *, struct snmp_pdu *, u_char **,
size_t *, size_t *),
int (*fcheck) (u_char *, size_t )
)
{
struct session_list *slp;
slp = (struct session_list *)snmp_sess_open(session);
if (!slp) return NULL;
slp->internal->hook_pre = fpre_parse;
slp->internal->hook_parse = fparse;
slp->internal->hook_post = fpost_parse;
slp->internal->hook_build = fbuild;
slp->internal->hook_realloc_build = frbuild;
slp->internal->check_packet = fcheck;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
slp->next = Sessions;
Sessions = slp;
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
return (slp->session);
}
static struct session_list *
_sess_copy( struct snmp_session *in_session)
{
struct session_list *slp;
struct snmp_internal_session *isp;
struct snmp_session *session;
struct snmp_secmod_def *sptr;
char *cp;
u_char *ucp;
size_t i;
in_session->s_snmp_errno = 0;
in_session->s_errno = 0;
/* Copy session structure and link into list */
slp = (struct session_list *)calloc(1,sizeof(struct session_list));
if (slp == NULL) {
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
slp->transport = NULL;
isp = (struct snmp_internal_session *)calloc(1,sizeof(struct snmp_internal_session));
if (isp == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
slp->internal = isp;
slp->session = (struct snmp_session *)malloc(sizeof(struct snmp_session));
if (slp->session == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
memmove(slp->session, in_session, sizeof(struct snmp_session));
session = slp->session;
/* zero out pointers so if we have to free the session we wont free mem
owned by in_session */
session->peername = NULL;
session->community = NULL;
session->contextEngineID = NULL;
session->contextName = NULL;
session->securityEngineID = NULL;
session->securityName = NULL;
session->securityAuthProto = NULL;
session->securityPrivProto = NULL;
/*
* session now points to the new structure that still contains pointers to
* data allocated elsewhere. Some of this data is copied to space malloc'd
* here, and the pointer replaced with the new one.
*/
if (in_session->peername != NULL){
session->peername = (char *)malloc(strlen(in_session->peername) + 1);
if (session->peername == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
strcpy(session->peername, in_session->peername);
}
/* Fill in defaults if necessary */
if (in_session->community_len != SNMP_DEFAULT_COMMUNITY_LEN){
ucp = (u_char *)malloc(in_session->community_len);
if (ucp != NULL)
memmove(ucp, in_session->community, in_session->community_len);
} else {
if ((cp = ds_get_string(DS_LIBRARY_ID, DS_LIB_COMMUNITY)) != NULL) {
session->community_len = strlen(cp);
ucp = (u_char *)malloc(session->community_len);
if (ucp)
memmove(ucp, cp, session->community_len);
}
else {
#ifdef NO_ZEROLENGTH_COMMUNITY
session->community_len = strlen(DEFAULT_COMMUNITY);
ucp = (u_char *)malloc(session->community_len);
if (ucp)
memmove(ucp, DEFAULT_COMMUNITY, session->community_len);
#else
ucp = (u_char *)strdup("");
#endif
}
}
if (ucp == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
session->community = ucp; /* replace pointer with pointer to new data */
if (session->securityLevel <= 0)
session->securityLevel = ds_get_int(DS_LIBRARY_ID, DS_LIB_SECLEVEL);
if (session->securityLevel == 0)
session->securityLevel = SNMP_SEC_LEVEL_NOAUTH;
if (in_session->securityAuthProtoLen > 0) {
session->securityAuthProto =
snmp_duplicate_objid(in_session->securityAuthProto,
in_session->securityAuthProtoLen);
if (session->securityAuthProto == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
} else if (get_default_authtype(&i) != NULL) {
session->securityAuthProto =
snmp_duplicate_objid(get_default_authtype(NULL), i);
session->securityAuthProtoLen = i;
}
if (in_session->securityPrivProtoLen > 0) {
session->securityPrivProto =
snmp_duplicate_objid(in_session->securityPrivProto,
in_session->securityPrivProtoLen);
if (session->securityPrivProto == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
} else if (get_default_privtype(&i) != NULL) {
session->securityPrivProto =
snmp_duplicate_objid(get_default_privtype(NULL), i);
session->securityPrivProtoLen = i;
}
if (in_session->securityEngineIDLen > 0) {
ucp = (u_char*)malloc(in_session->securityEngineIDLen);
if (ucp == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
memmove(ucp, in_session->securityEngineID,
in_session->securityEngineIDLen);
session->securityEngineID = ucp;
}
if (in_session->contextEngineIDLen > 0) {
ucp = (u_char*)malloc(in_session->contextEngineIDLen);
if (ucp == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
memmove(ucp, in_session->contextEngineID,
in_session->contextEngineIDLen);
session->contextEngineID = ucp;
} else if (in_session->securityEngineIDLen > 0) {
/* default contextEngineID to securityEngineIDLen if defined */
ucp = (u_char*)malloc(in_session->securityEngineIDLen);
if (ucp == NULL) {
snmp_sess_close(slp);
in_session->s_snmp_errno = SNMPERR_MALLOC;
return(NULL);
}
memmove(ucp, in_session->securityEngineID,
in_session->securityEngineIDLen);
session->contextEngineID = ucp;
session->contextEngineIDLen = in_session->securityEngineIDLen;
}
if (in_session->contextName) {
session->contextName = strdup(in_session->contextName);
if (session->contextName == NULL) {
snmp_sess_close(slp);
return(NULL);
}
} else if ((cp = ds_get_string(DS_LIBRARY_ID, DS_LIB_CONTEXT)) != NULL) {
cp = strdup(cp);
if (cp == NULL) {
snmp_sess_close(slp);
return(NULL);
}
session->contextName = cp;
session->contextNameLen = strlen(cp);
} else {
cp = strdup(SNMP_DEFAULT_CONTEXT);
session->contextName = cp;
session->contextNameLen = strlen(cp);
}
if (in_session->securityName) {
session->securityName = strdup(in_session->securityName);
if (session->securityName == NULL) {
snmp_sess_close(slp);
return(NULL);
}
} else if ((cp = ds_get_string(DS_LIBRARY_ID, DS_LIB_SECNAME)) != NULL) {
cp = strdup(cp);
if (cp == NULL) {
snmp_sess_close(slp);
return(NULL);
}
session->securityName = cp;
session->securityNameLen = strlen(cp);
}
if ((in_session->securityAuthKeyLen <= 0) &&
(cp = ds_get_string(DS_LIBRARY_ID, DS_LIB_AUTHPASSPHRASE))) {
session->securityAuthKeyLen = USM_AUTH_KU_LEN;
if (generate_Ku(session->securityAuthProto,
session->securityAuthProtoLen,
(u_char*)cp, strlen(cp),
session->securityAuthKey,
&session->securityAuthKeyLen) != SNMPERR_SUCCESS) {
snmp_set_detail("Error generating Ku from authentication pass phrase.");
snmp_sess_close(slp);
return NULL;
}
}
if ((in_session->securityPrivKeyLen <= 0) &&
(cp = ds_get_string(DS_LIBRARY_ID, DS_LIB_PRIVPASSPHRASE))) {
session->securityPrivKeyLen = USM_PRIV_KU_LEN;
if (generate_Ku(session->securityAuthProto,
session->securityAuthProtoLen,
(u_char *)cp, strlen(cp),
session->securityPrivKey,
&session->securityPrivKeyLen) != SNMPERR_SUCCESS) {
snmp_set_detail("Error generating Ku from privacy pass phrase.");
snmp_sess_close(slp);
return NULL;
}
}
if (session->retries == SNMP_DEFAULT_RETRIES)
session->retries = DEFAULT_RETRIES;
if (session->timeout == SNMP_DEFAULT_TIMEOUT)
session->timeout = DEFAULT_TIMEOUT;
session->sessid = snmp_get_next_sessid();
snmp_call_callbacks(SNMP_CALLBACK_LIBRARY, SNMP_CALLBACK_SESSION_INIT,
session);
if ((sptr = find_sec_mod(session->securityModel)) != NULL &&
sptr->session_open != NULL) {
/* security module specific inialization */
(*sptr->session_open)(session);
}
return( slp );
}
static struct session_list *
snmp_sess_copy( struct snmp_session *pss)
{
struct session_list * psl;
psl = _sess_copy(pss);
if (!psl) {
if (!pss->s_snmp_errno) {
pss->s_snmp_errno = SNMPERR_GENERR;
}
SET_SNMP_ERROR(pss->s_snmp_errno);
}
return psl;
}
int snmpv3_engineID_probe (struct session_list *slp,
struct snmp_session *in_session)
{
struct snmp_pdu *pdu = NULL, *response = NULL;
struct snmp_session *session;
int i, status;
if (slp == NULL || slp->session == NULL) {
return 0;
}
session = slp->session;
/* If we are opening a V3 session and we don't know engineID we must probe
it -- this must be done after the session is created and inserted in the
list so that the response can handled correctly. */
if ((session->flags & SNMP_FLAGS_DONT_PROBE) == SNMP_FLAGS_DONT_PROBE)
return 1;
if (session->version == SNMP_VERSION_3) {
if (session->securityEngineIDLen == 0) {
if (snmpv3_build_probe_pdu(&pdu) != 0) {
DEBUGMSGTL(("snmp_api","unable to create probe PDU\n"));
return 0;
}
DEBUGMSGTL(("snmp_api","probing for engineID...\n"));
status = snmp_sess_synch_response(slp, pdu, &response);
if ((response == NULL) && (status == STAT_SUCCESS)) {
status = STAT_ERROR;
}
switch (status) {
case STAT_SUCCESS:
in_session->s_snmp_errno = SNMPERR_INVALID_MSG; /* XX?? */
DEBUGMSGTL(("snmp_sess_open",
"error: expected Report as response to probe: %s (%d)\n",
snmp_errstring(response->errstat), response->errstat));
break;
case STAT_ERROR: /* this is what we expected -> Report == STAT_ERROR */
in_session->s_snmp_errno = SNMPERR_UNKNOWN_ENG_ID;
break;
case STAT_TIMEOUT:
in_session->s_snmp_errno = SNMPERR_TIMEOUT;
default:
DEBUGMSGTL(("snmp_sess_open",
"unable to connect with remote engine: %s (%d)\n",
snmp_api_errstring(session->s_snmp_errno),
session->s_snmp_errno));
break;
}
if (slp->session->securityEngineIDLen == 0) {
DEBUGMSGTL(("snmp_api","unable to determine remote engine ID\n"));
return 0;
}
in_session->s_snmp_errno = SNMPERR_SUCCESS;
if (snmp_get_do_debugging()) {
DEBUGMSGTL(("snmp_sess_open", " probe found engineID: "));
for(i = 0; i < slp->session->securityEngineIDLen; i++)
DEBUGMSG(("snmp_sess_open", "%02x",
slp->session->securityEngineID[i]));
DEBUGMSG(("snmp_sess_open","\n"));
}
}
/* if boot/time supplied set it for this engineID */
if (session->engineBoots || session->engineTime) {
set_enginetime(session->securityEngineID, session->securityEngineIDLen,
session->engineBoots, session->engineTime, TRUE);
}
if (create_user_from_session(slp->session) != SNMPERR_SUCCESS) {
in_session->s_snmp_errno = SNMPERR_UNKNOWN_USER_NAME; /* XX?? */
DEBUGMSGTL(("snmp_api","snmp_sess_open(): failed(2) to create a new user from session\n"));
return 0;
}
}
return 1;
}
/*******************************************************************-o-******
* snmp_sess_open
*
* Parameters:
* *in_session
*
* Returns:
* Pointer to a session in the session list -OR- FIX -- right?
* NULL on failure.
*
* The "spin-free" version of snmp_open.
*/
static void *
_sess_open(struct snmp_session *in_session)
{
struct session_list *slp;
struct snmp_internal_session *isp;
struct snmp_session *session;
in_session->s_snmp_errno = 0;
in_session->s_errno = 0;
if (Reqid == 0) {
_init_snmp();
}
if ((slp = snmp_sess_copy(in_session)) == NULL) {
return(NULL);
}
isp = slp->internal;
session = slp->session;
slp->transport = NULL;
if (session->flags & SNMP_FLAGS_STREAM_SOCKET) {
slp->transport = snmp_tdomain_transport(session->peername,
session->local_port, "tcp");
} else {
slp->transport = snmp_tdomain_transport(session->peername,
session->local_port, "udp");
}
if (slp->transport == NULL) {
DEBUGMSGTL(("_sess_open", "couldn't interpret peername\n"));
in_session->s_snmp_errno = SNMPERR_BAD_ADDRESS;
in_session->s_errno = errno;
snmp_set_detail(session->peername);
snmp_sess_close(slp);
return NULL;
}
session->rcvMsgMaxSize = slp->transport->msgMaxSize;
if (!snmpv3_engineID_probe(slp, in_session)) {
snmp_sess_close(slp);
return 0;
}
return (void *)slp;
} /* end snmp_sess_open() */
/* EXPERIMENTAL API EXTENSIONS ------------------------------------------
snmp_sess_add_ex, snmp_sess_add, snmp_add
Analogous to snmp_open family of functions, but taking an snmp_transport
pointer as an extra argument. Unlike snmp_open et al. it doesn't attempt
to interpret the in_session->peername as a transport endpoint specifier,
but instead uses the supplied transport. JBPN
*/
struct snmp_session *snmp_add(
struct snmp_session *in_session,
snmp_transport *transport,
int (*fpre_parse) (struct snmp_session *, snmp_transport *, void *, int),
int (*fpost_parse) (struct snmp_session *, struct snmp_pdu *, int))
{
struct session_list *slp;
slp = (struct session_list *)snmp_sess_add_ex(in_session, transport,
fpre_parse, NULL, fpost_parse,
NULL, NULL, NULL);
if (slp == NULL) {
return NULL;
}
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
slp->next = Sessions;
Sessions = slp;
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
return (slp->session);
}
void *snmp_sess_add_ex(
struct snmp_session *in_session,
snmp_transport *transport,
int (*fpre_parse) (struct snmp_session *, snmp_transport *, void *, int),
int (*fparse) (struct snmp_session *, struct snmp_pdu *, u_char *, size_t),
int (*fpost_parse) (struct snmp_session *, struct snmp_pdu *, int),
int (*fbuild) (struct snmp_session *, struct snmp_pdu *, u_char *, size_t *),
int (*frbuild)(struct snmp_session *, struct snmp_pdu *, u_char **,
size_t *, size_t *),
int (*fcheck) (u_char *, size_t))
{
struct session_list *slp;
if (Reqid == 0) {
_init_snmp();
}
if (in_session == NULL || transport == NULL) {
return NULL;
}
DEBUGMSGTL(("snmp_sess_add", "fd %d\n", transport->sock));
if ((slp = snmp_sess_copy(in_session)) == NULL) {
return(NULL);
}
slp->transport = transport;
slp->internal->hook_pre = fpre_parse;
slp->internal->hook_parse = fparse;
slp->internal->hook_post = fpost_parse;
slp->internal->hook_build = fbuild;
slp->internal->hook_realloc_build = frbuild;
slp->internal->check_packet = fcheck;
slp->session->rcvMsgMaxSize = transport->msgMaxSize;
if (slp->session->version == SNMP_VERSION_3) {
DEBUGMSGTL(("snmp_sess_add", "adding v3 session -- engineID probe now\n"));
if (!snmpv3_engineID_probe(slp, in_session)) {
DEBUGMSGTL(("snmp_sess_add", "engine ID probe failed\n"));
snmp_sess_close(slp);
slp = NULL;
}
}
return (void *)slp;
} /* end snmp_sess_add_ex() */
void *snmp_sess_add (
struct snmp_session *in_session,
snmp_transport *transport,
int (*fpre_parse) (struct snmp_session *, snmp_transport *, void *, int),
int (*fpost_parse) (struct snmp_session *, struct snmp_pdu *, int))
{
return snmp_sess_add_ex(in_session, transport, fpre_parse, NULL,
fpost_parse, NULL, NULL, NULL);
}
void *
snmp_sess_open(struct snmp_session *pss)
{
void * pvoid;
pvoid = _sess_open(pss);
if ( !pvoid) {
SET_SNMP_ERROR(pss->s_snmp_errno);
}
return pvoid;
}
/* create_user_from_session(struct snmp_session *session):
creates a user in the usm table from the information in a session.
If the user already exists, it is updated with the current
information from the session
Parameters:
session -- IN: pointer to the session to use when creating the user.
Returns:
SNMPERR_SUCCESS
SNMPERR_GENERR
*/
int
create_user_from_session(struct snmp_session *session)
{
struct usmUser *user;
int user_just_created = 0;
/* now that we have the engineID, create an entry in the USM list
for this user using the information in the session */
user = usm_get_user_from_list(session->securityEngineID,
session->securityEngineIDLen,
session->securityName,
usm_get_userList(), 0);
if (user == NULL) {
DEBUGMSGTL(("snmp_api","Building user %s...\n",session->securityName));
/* user doesn't exist so we create and add it */
user = (struct usmUser *) calloc(1,sizeof(struct usmUser));
if (user == NULL)
return SNMPERR_GENERR;
/* copy in the securityName */
if (session->securityName) {
user->name = strdup(session->securityName);
user->secName = strdup(session->securityName);
if (user->name == NULL || user->secName == NULL) {
usm_free_user(user);
return SNMPERR_GENERR;
}
}
/* copy in the engineID */
if (memdup(&user->engineID, session->securityEngineID,
session->securityEngineIDLen) != SNMPERR_SUCCESS) {
usm_free_user(user);
return SNMPERR_GENERR;
}
user->engineIDLen = session->securityEngineIDLen;
user_just_created = 1;
}
/* copy the auth protocol */
if (session->securityAuthProto != NULL) {
SNMP_FREE(user->authProtocol);
user->authProtocol =
snmp_duplicate_objid(session->securityAuthProto,
session->securityAuthProtoLen);
if (user->authProtocol == NULL) {
usm_free_user(user);
return SNMPERR_GENERR;
}
user->authProtocolLen = session->securityAuthProtoLen;
}
/* copy the priv protocol */
if (session->securityPrivProto != NULL) {
SNMP_FREE(user->privProtocol);
user->privProtocol =
snmp_duplicate_objid(session->securityPrivProto,
session->securityPrivProtoLen);
if (user->privProtocol == NULL) {
usm_free_user(user);
return SNMPERR_GENERR;
}
user->privProtocolLen = session->securityPrivProtoLen;
}
/* copy in the authentication Key, and convert to the localized version */
if (session->securityAuthKey != NULL && session->securityAuthKeyLen != 0) {
SNMP_FREE(user->authKey);
user->authKey = (u_char *)calloc(1,USM_LENGTH_KU_HASHBLOCK);
if (user->authKey == NULL) {
usm_free_user(user);
return SNMPERR_GENERR;
}
user->authKeyLen = USM_LENGTH_KU_HASHBLOCK;
if (generate_kul( user->authProtocol, user->authProtocolLen,
session->securityEngineID, session->securityEngineIDLen,
session->securityAuthKey, session->securityAuthKeyLen,
user->authKey, &user->authKeyLen ) != SNMPERR_SUCCESS) {
usm_free_user(user);
return SNMPERR_GENERR;
}
}
/* copy in the privacy Key, and convert to the localized version */
if (session->securityPrivKey != NULL && session->securityPrivKeyLen != 0) {
SNMP_FREE(user->privKey);
user->privKey = (u_char *)calloc(1,USM_LENGTH_KU_HASHBLOCK);
if (user->privKey == NULL) {
usm_free_user(user);
return SNMPERR_GENERR;
}
user->privKeyLen = USM_LENGTH_KU_HASHBLOCK;
if (generate_kul( user->authProtocol, user->authProtocolLen,
session->securityEngineID, session->securityEngineIDLen,
session->securityPrivKey, session->securityPrivKeyLen,
user->privKey, &user->privKeyLen ) != SNMPERR_SUCCESS) {
usm_free_user(user);
return SNMPERR_GENERR;
}
}
user->userStatus = RS_ACTIVE;
user->userStorageType = ST_READONLY;
if (user_just_created) {
/* add the user into the database */
usm_add_user(user);
}
return SNMPERR_SUCCESS;
} /* end create_user_from_session() */
/*
* Do a "deep free()" of a struct snmp_session.
*
* CAUTION: SHOULD ONLY BE USED FROM snmp_sess_close() OR SIMILAR.
* (hence it is static)
*/
static void
snmp_free_session(struct snmp_session *s)
{
if (s) {
SNMP_FREE(s->peername);
SNMP_FREE(s->community);
SNMP_FREE(s->contextEngineID);
SNMP_FREE(s->contextName);
SNMP_FREE(s->securityEngineID);
SNMP_FREE(s->securityName);
SNMP_FREE(s->securityAuthProto);
SNMP_FREE(s->securityPrivProto);
free((char *)s);
}
}
/*
* Close the input session. Frees all data allocated for the session,
* dequeues any pending requests, and closes any sockets allocated for
* the session. Returns 0 on error, 1 otherwise.
*/
int
snmp_sess_close(void *sessp)
{
struct session_list *slp = (struct session_list *)sessp;
snmp_transport *transport;
struct snmp_internal_session *isp;
struct snmp_session *sesp = NULL;
struct snmp_secmod_def *sptr;
if (slp == NULL) {
return 0;
}
if ((sptr = find_sec_mod(slp->session->securityModel)) != NULL &&
sptr->session_close != NULL) {
(*sptr->session_close)(slp->session);
}
isp = slp->internal; slp->internal = 0;
if (isp) {
struct request_list *rp, *orp;
SNMP_FREE(isp->packet);
/* Free each element in the input request list. */
rp = isp->requests;
while(rp) {
orp = rp;
rp = rp->next_request;
snmp_free_pdu(orp->pdu);
free((char *)orp);
}
free((char *)isp);
}
transport = slp->transport; slp->transport = 0;
if (transport) {
transport->f_close(transport);
snmp_transport_free(transport);
}
sesp = slp->session; slp->session = 0;
/* The following is necessary to avoid memory leakage when closing AgentX
sessions that may have multiple subsessions. These hang off the main
session at ->subsession, and chain through ->next. */
if (sesp != NULL && sesp->subsession != NULL) {
struct snmp_session *subsession = sesp->subsession, *tmpsub;
while (subsession != NULL) {
DEBUGMSGTL(("snmp_sess_close", "closing session %p, subsession %p\n",
sesp, subsession));
tmpsub = subsession->next;
snmp_free_session(subsession);
subsession = tmpsub;
}
}
snmp_free_session(sesp);
free((char *)slp);
return 1;
}
int
snmp_close(struct snmp_session *session)
{
struct session_list *slp = NULL, *oslp = NULL;
{ /*MTCRITICAL_RESOURCE*/
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
if (Sessions && Sessions->session == session){ /* If first entry */
slp = Sessions;
Sessions = slp->next;
} else {
for(slp = Sessions; slp; slp = slp->next){
if (slp->session == session){
if (oslp) /* if we found entry that points here */
oslp->next = slp->next; /* link around this entry */
break;
}
oslp = slp;
}
}
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
} /*END MTCRITICAL_RESOURCE*/
if (slp == NULL){
return 0;
}
return snmp_sess_close((void *)slp);
}
int
snmp_close_sessions( void )
{
struct session_list *slp;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
while ( Sessions ) {
slp = Sessions;
Sessions = Sessions->next;
snmp_sess_close((void *)slp);
}
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
return 1;
}
static int
snmpv3_build_probe_pdu (struct snmp_pdu **pdu)
{
struct usmUser *user;
/* create the pdu */
if (!pdu) return -1;
*pdu = snmp_pdu_create(SNMP_MSG_GET);
if (!(*pdu) ) return -1;
(*pdu)->version = SNMP_VERSION_3;
(*pdu)->securityName = strdup("");
(*pdu)->securityNameLen = strlen((*pdu)->securityName);
(*pdu)->securityLevel = SNMP_SEC_LEVEL_NOAUTH;
(*pdu)->securityModel = SNMP_SEC_MODEL_USM;
/* create the empty user */
user = usm_get_user(NULL, 0, (*pdu)->securityName);
if (user == NULL) {
user = (struct usmUser *) calloc(1,sizeof(struct usmUser));
if (user == NULL) {
snmp_free_pdu(*pdu);
*pdu = (struct snmp_pdu *)NULL;
return -1;
}
user->name = strdup((*pdu)->securityName);
user->secName = strdup((*pdu)->securityName);
user->authProtocolLen = sizeof(usmNoAuthProtocol)/sizeof(oid);
user->authProtocol =
snmp_duplicate_objid(usmNoAuthProtocol, user->authProtocolLen);
user->privProtocolLen = sizeof(usmNoPrivProtocol)/sizeof(oid);
user->privProtocol =
snmp_duplicate_objid(usmNoPrivProtocol, user->privProtocolLen);
usm_add_user(user);
}
return 0;
}
static void
snmpv3_calc_msg_flags (int sec_level, int msg_command, u_char *flags)
{
*flags = 0;
if (sec_level == SNMP_SEC_LEVEL_AUTHNOPRIV)
*flags = SNMP_MSG_FLAG_AUTH_BIT;
else if (sec_level == SNMP_SEC_LEVEL_AUTHPRIV)
*flags = SNMP_MSG_FLAG_AUTH_BIT | SNMP_MSG_FLAG_PRIV_BIT;
if (SNMP_CMD_CONFIRMED(msg_command)) *flags |= SNMP_MSG_FLAG_RPRT_BIT;
return;
}
static int
snmpv3_verify_msg(struct request_list *rp, struct snmp_pdu *pdu)
{
struct snmp_pdu *rpdu;
if (!rp || !rp->pdu || !pdu) return 0;
/* Reports don't have to match anything according to the spec */
if (pdu->command == SNMP_MSG_REPORT) return 1;
rpdu = rp->pdu;
if (rp->request_id != pdu->reqid || rpdu->reqid != pdu->reqid) return 0;
if (rpdu->version != pdu->version) return 0;
if (rpdu->securityModel != pdu->securityModel) return 0;
if (rpdu->securityLevel != pdu->securityLevel) return 0;
if (rpdu->contextEngineIDLen != pdu->contextEngineIDLen ||
memcmp(rpdu->contextEngineID, pdu->contextEngineID,
pdu->contextEngineIDLen))
return 0;
if (rpdu->contextNameLen != pdu->contextNameLen ||
memcmp(rpdu->contextName, pdu->contextName, pdu->contextNameLen))
return 0;
if (rpdu->securityEngineIDLen != pdu->securityEngineIDLen ||
memcmp(rpdu->securityEngineID, pdu->securityEngineID,
pdu->securityEngineIDLen))
return 0;
if (rpdu->securityNameLen != pdu->securityNameLen ||
memcmp(rpdu->securityName, pdu->securityName, pdu->securityNameLen))
return 0;
return 1;
}
/* SNMPv3
* Takes a session and a pdu and serializes the ASN PDU into the area
* pointed to by packet. out_length is the size of the data area available.
* Returns the length of the completed packet in out_length. If any errors
* occur, -1 is returned. If all goes well, 0 is returned.
*/
static int
snmpv3_build(u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_session *session, struct snmp_pdu *pdu)
{
int ret;
session->s_snmp_errno = 0;
session->s_errno = 0;
/* do validation for PDU types */
switch (pdu->command) {
case SNMP_MSG_RESPONSE:
case SNMP_MSG_TRAP2:
case SNMP_MSG_REPORT:
pdu->flags &= (~UCD_MSG_FLAG_EXPECT_RESPONSE);
/* Fallthrough */
case SNMP_MSG_GET:
case SNMP_MSG_GETNEXT:
case SNMP_MSG_SET:
case SNMP_MSG_INFORM:
if (pdu->errstat == SNMP_DEFAULT_ERRSTAT)
pdu->errstat = 0;
if (pdu->errindex == SNMP_DEFAULT_ERRINDEX)
pdu->errindex = 0;
break;
case SNMP_MSG_GETBULK:
if (pdu->max_repetitions < 0) {
session->s_snmp_errno = SNMPERR_BAD_REPETITIONS;
return -1;
}
if (pdu->non_repeaters < 0) {
session->s_snmp_errno = SNMPERR_BAD_REPEATERS;
return -1;
}
break;
case SNMP_MSG_TRAP:
session->s_snmp_errno = SNMPERR_V1_IN_V2;
return -1;
default:
session->s_snmp_errno = SNMPERR_UNKNOWN_PDU;
return -1;
}
if (pdu->securityEngineIDLen == 0) {
if (session->securityEngineIDLen) {
snmpv3_clone_engineID(&pdu->securityEngineID,
&pdu->securityEngineIDLen,
session->securityEngineID,
session->securityEngineIDLen);
}
}
if (pdu->contextEngineIDLen == 0) {
if (session->contextEngineIDLen) {
snmpv3_clone_engineID(&pdu->contextEngineID,
&pdu->contextEngineIDLen,
session->contextEngineID,
session->contextEngineIDLen);
} else if (pdu->securityEngineIDLen) {
snmpv3_clone_engineID(&pdu->contextEngineID,
&pdu->contextEngineIDLen,
pdu->securityEngineID,
pdu->securityEngineIDLen);
}
}
if (pdu->contextName == NULL) {
if (!session->contextName){
session->s_snmp_errno = SNMPERR_BAD_CONTEXT;
return -1;
}
pdu->contextName = strdup(session->contextName);
if (pdu->contextName == NULL) {
session->s_snmp_errno = SNMPERR_GENERR;
return -1;
}
pdu->contextNameLen = session->contextNameLen;
}
if (pdu->securityModel == SNMP_DEFAULT_SECMODEL) {
pdu->securityModel = session->securityModel;
if (pdu->securityModel == SNMP_DEFAULT_SECMODEL) {
pdu->securityModel = SNMP_SEC_MODEL_USM;
}
}
if (pdu->securityNameLen == 0 && pdu->securityName == 0) {
if (session->securityNameLen == 0){
session->s_snmp_errno = SNMPERR_BAD_SEC_NAME;
return -1;
}
pdu->securityName = strdup(session->securityName);
if (pdu->securityName == NULL) {
session->s_snmp_errno = SNMPERR_GENERR;
return -1;
}
pdu->securityNameLen = session->securityNameLen;
}
if (pdu->securityLevel == 0) {
if (session->securityLevel == 0) {
session->s_snmp_errno = SNMPERR_BAD_SEC_LEVEL;
return -1;
}
pdu->securityLevel = session->securityLevel;
}
DEBUGMSGTL(("snmp_build",
"Building SNMPv3 message (secName:\"%s\", secLevel:%s)...\n",
((session->securityName) ? (char *)session->securityName :
((pdu->securityName) ? (char *)pdu->securityName :
"ERROR: undefined")),
secLevelName[pdu->securityLevel]));
DEBUGDUMPSECTION("send", "SNMPv3 Message");
#ifdef USE_REVERSE_ASNENCODING
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_REVERSE_ENCODE)) {
ret = snmpv3_packet_realloc_rbuild(pkt, pkt_len, offset,
session, pdu, NULL, 0);
} else {
#endif
ret = snmpv3_packet_build(session, pdu, *pkt, pkt_len, NULL, 0);
#ifdef USE_REVERSE_ASNENCODING
}
#endif
DEBUGINDENTLESS();
if (-1 != ret) {
session->s_snmp_errno = ret;
}
return ret;
} /* end snmpv3_build() */
static u_char *
snmpv3_header_build(struct snmp_session *session, struct snmp_pdu *pdu,
u_char *packet, size_t *out_length,
size_t length, u_char **msg_hdr_e)
{
u_char *global_hdr, *global_hdr_e;
u_char *cp;
u_char msg_flags;
long max_size;
long sec_model;
u_char *pb, *pb0e;
/* Save current location and build SEQUENCE tag and length placeholder
* for SNMP message sequence (actual length inserted later)
*/
cp = asn_build_sequence(packet, out_length,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR), length);
if (cp == NULL) return NULL;
if (msg_hdr_e != NULL)
*msg_hdr_e = cp;
pb0e = cp;
/* store the version field - msgVersion
*/
DEBUGDUMPHEADER("send", "SNMP Version Number");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *) &pdu->version, sizeof(pdu->version));
DEBUGINDENTLESS();
if (cp == NULL) return NULL;
global_hdr = cp;
/* msgGlobalData HeaderData */
DEBUGDUMPSECTION("send", "msgGlobalData");
cp = asn_build_sequence(cp, out_length,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR), 0);
if (cp == NULL) return NULL;
global_hdr_e = cp;
/* msgID */
DEBUGDUMPHEADER("send", "msgID");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->msgid, sizeof(pdu->msgid));
DEBUGINDENTLESS();
if (cp == NULL) return NULL;
/* msgMaxSize */
max_size = session->rcvMsgMaxSize;
DEBUGDUMPHEADER("send", "msgMaxSize");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&max_size, sizeof(max_size));
DEBUGINDENTLESS();
if (cp == NULL) return NULL;
/* msgFlags */
snmpv3_calc_msg_flags(pdu->securityLevel, pdu->command, &msg_flags);
DEBUGDUMPHEADER("send", "msgFlags");
cp = asn_build_string(cp, out_length,
(u_char)(ASN_UNIVERSAL|ASN_PRIMITIVE|ASN_OCTET_STR),
&msg_flags, sizeof(msg_flags));
DEBUGINDENTLESS();
if (cp == NULL) return NULL;
/* msgSecurityModel */
sec_model = pdu->securityModel;
DEBUGDUMPHEADER("send", "msgSecurityModel");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&sec_model, sizeof(sec_model));
DEBUGINDENTADD(-4); /* return from global data indent */
if (cp == NULL) return NULL;
/* insert actual length of globalData
*/
pb = asn_build_sequence(global_hdr, out_length,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
cp - global_hdr_e);
if (pb == NULL) return NULL;
/* insert the actual length of the entire packet
*/
pb = asn_build_sequence(packet, out_length,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
length + (cp - pb0e));
if (pb == NULL) return NULL;
return cp;
} /* end snmpv3_header_build() */
#ifdef USE_REVERSE_ASNENCODING
static int
snmpv3_header_realloc_rbuild(u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_session *session, struct snmp_pdu *pdu)
{
size_t start_offset = *offset;
u_char msg_flags;
long max_size, sec_model;
int rc = 0;
/* msgSecurityModel. */
sec_model = pdu->securityModel;
DEBUGDUMPHEADER("send", "msgSecurityModel");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&sec_model, sizeof(sec_model));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* msgFlags. */
snmpv3_calc_msg_flags(pdu->securityLevel, pdu->command, &msg_flags);
DEBUGDUMPHEADER("send", "msgFlags");
rc = asn_realloc_rbuild_string(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OCTET_STR),
&msg_flags, sizeof(msg_flags));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* msgMaxSize. */
max_size = session->rcvMsgMaxSize;
DEBUGDUMPHEADER("send", "msgMaxSize");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&max_size, sizeof(max_size));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* msgID. */
DEBUGDUMPHEADER("send", "msgID");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->msgid, sizeof(pdu->msgid));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* Global data sequence. */
rc = asn_realloc_rbuild_sequence(pkt, pkt_len, offset, 1,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
*offset - start_offset);
if (rc == 0) {
return 0;
}
/* Store the version field - msgVersion. */
DEBUGDUMPHEADER("send", "SNMP Version Number");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *)&pdu->version, sizeof(pdu->version));
DEBUGINDENTLESS();
return rc;
} /* end snmpv3_header_realloc_rbuild() */
#endif /* USE_REVERSE_ASNENCODING */
static u_char *
snmpv3_scopedPDU_header_build(struct snmp_pdu *pdu,
u_char *packet, size_t *out_length,
u_char **spdu_e)
{
size_t init_length;
u_char *scopedPdu, *pb;
init_length = *out_length;
pb = scopedPdu = packet;
pb = asn_build_sequence(pb, out_length,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR), 0);
if (pb == NULL) return NULL;
if (spdu_e)
*spdu_e = pb;
DEBUGDUMPHEADER("send", "contextEngineID");
pb = asn_build_string(pb, out_length,
(ASN_UNIVERSAL|ASN_PRIMITIVE|ASN_OCTET_STR),
pdu->contextEngineID, pdu->contextEngineIDLen);
DEBUGINDENTLESS();
if (pb == NULL) return NULL;
DEBUGDUMPHEADER("send", "contextName");
pb = asn_build_string(pb, out_length,
(ASN_UNIVERSAL|ASN_PRIMITIVE|ASN_OCTET_STR),
(u_char *)pdu->contextName, pdu->contextNameLen);
DEBUGINDENTLESS();
if (pb == NULL) return NULL;
return pb;
} /* end snmpv3_scopedPDU_header_build() */
#ifdef USE_REVERSE_ASNENCODING
static int
snmpv3_scopedPDU_header_realloc_rbuild(u_char **pkt, size_t *pkt_len,
size_t *offset, struct snmp_pdu *pdu,
size_t body_len)
{
size_t start_offset = *offset;
int rc = 0;
/* contextName. */
DEBUGDUMPHEADER("send", "contextName");
rc = asn_realloc_rbuild_string(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OCTET_STR),
(u_char *)pdu->contextName, pdu->contextNameLen);
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* contextEngineID. */
DEBUGDUMPHEADER("send", "contextEngineID");
rc = asn_realloc_rbuild_string(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OCTET_STR),
pdu->contextEngineID, pdu->contextEngineIDLen);
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
rc = asn_realloc_rbuild_sequence(pkt, pkt_len, offset, 1,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
*offset - start_offset + body_len);
return rc;
} /* end snmpv3_scopedPDU_header_realloc_rbuild() */
#endif /* USE_REVERSE_ASNENCODING */
#ifdef USE_REVERSE_ASNENCODING
/* returns 0 if success, -1 if fail, not 0 if SM build failure */
int
snmpv3_packet_realloc_rbuild(u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_session *session,
struct snmp_pdu *pdu,
u_char *pdu_data, size_t pdu_data_len)
{
u_char *scoped_pdu, *hdrbuf = NULL, *hdr = NULL;
size_t hdrbuf_len = SNMP_MAX_MSG_V3_HDRS, hdr_offset = 0, spdu_offset = 0;
size_t body_end_offset = *offset, body_len = 0;
struct snmp_secmod_def *sptr = NULL;
int rc = 0;
/* Build a scopedPDU structure into the packet buffer. */
DEBUGPRINTPDUTYPE("send", pdu->command);
if (pdu_data) {
while ((*pkt_len - *offset) < pdu_data_len) {
if (!asn_realloc(pkt, pkt_len)) {
return -1;
}
}
*offset += pdu_data_len;
memcpy(*pkt + *pkt_len - *offset, pdu_data, pdu_data_len);
} else {
rc = snmp_pdu_realloc_rbuild(pkt, pkt_len, offset, pdu);
if (rc == 0) {
return -1;
}
}
body_len = *offset - body_end_offset;
DEBUGDUMPSECTION("send", "ScopedPdu");
rc = snmpv3_scopedPDU_header_realloc_rbuild(pkt, pkt_len, offset,
pdu, body_len);
if (rc == 0) {
return -1;
}
spdu_offset = *offset;
DEBUGINDENTADD(-4); /* Return from Scoped PDU. */
if ((hdrbuf = (u_char *)malloc(hdrbuf_len)) == NULL) {
return -1;
}
rc = snmpv3_header_realloc_rbuild(&hdrbuf, &hdrbuf_len, &hdr_offset,
session, pdu);
if (rc == 0) {
free(hdrbuf);
return -1;
}
hdr = hdrbuf + hdrbuf_len - hdr_offset;
scoped_pdu = *pkt + *pkt_len - spdu_offset;
/* Call the security module to possibly encrypt and authenticate the
message---the entire message to transmitted on the wire is returned. */
sptr = find_sec_mod(pdu->securityModel);
DEBUGDUMPSECTION("send", "SM msgSecurityParameters");
if (sptr && sptr->encode_reverse) {
struct snmp_secmod_outgoing_params parms;
parms.msgProcModel = pdu->msgParseModel;
parms.globalData = hdr;
parms.globalDataLen = hdr_offset;
parms.maxMsgSize = SNMP_MAX_MSG_SIZE;
parms.secModel = pdu->securityModel;
parms.secEngineID = pdu->securityEngineID;
parms.secEngineIDLen = pdu->securityEngineIDLen;
parms.secName = pdu->securityName;
parms.secNameLen = pdu->securityNameLen;
parms.secLevel = pdu->securityLevel;
parms.scopedPdu = scoped_pdu;
parms.scopedPduLen = spdu_offset;
parms.secStateRef = pdu->securityStateRef;
parms.wholeMsg = pkt;
parms.wholeMsgLen = pkt_len;
parms.wholeMsgOffset = offset;
parms.session = session;
parms.pdu = pdu;
rc = (*sptr->encode_reverse)(&parms);
} else {
if (!sptr) {
snmp_log(LOG_ERR,
"no such security service available: %d\n",
pdu->securityModel);
} else if (!sptr->encode_reverse) {
snmp_log(LOG_ERR,
"security service %d doesn't support reverse encoding.\n",
pdu->securityModel);
}
rc = -1;
}
DEBUGINDENTLESS();
free(hdrbuf);
return rc;
} /* end snmpv3_packet_realloc_rbuild() */
#endif /* USE_REVERSE_ASNENCODING */
/* returns 0 if success, -1 if fail, not 0 if SM build failure */
int
snmpv3_packet_build(struct snmp_session *session, struct snmp_pdu *pdu,
u_char *packet, size_t *out_length,
u_char *pdu_data, size_t pdu_data_len)
{
u_char *global_data, *sec_params, *spdu_hdr_e;
size_t global_data_len, sec_params_len;
u_char spdu_buf[SNMP_MAX_MSG_SIZE];
size_t spdu_buf_len, spdu_len;
u_char *cp;
int result;
struct snmp_secmod_def *sptr;
global_data = packet;
/*
* build the headers for the packet, returned addr = start of secParams
*/
sec_params = snmpv3_header_build(session, pdu, global_data,
out_length, 0, NULL);
if (sec_params == NULL) return -1;
global_data_len = sec_params - global_data;
sec_params_len = *out_length; /* length left in packet buf for sec_params */
/*
* build a scopedPDU structure into spdu_buf
*/
spdu_buf_len = SNMP_MAX_MSG_SIZE;
DEBUGDUMPSECTION("send", "ScopedPdu");
cp = snmpv3_scopedPDU_header_build(pdu,spdu_buf,&spdu_buf_len,&spdu_hdr_e);
if (cp == NULL) return -1;
/* build the PDU structure onto the end of spdu_buf
*/
DEBUGPRINTPDUTYPE("send", ((pdu_data) ? *pdu_data : 0x00));
if (pdu_data) {
memcpy(cp, pdu_data, pdu_data_len);
cp += pdu_data_len;
} else {
cp = snmp_pdu_build(pdu, cp, &spdu_buf_len);
if (cp == NULL) return -1;
}
DEBUGINDENTADD(-4); /* return from Scoped PDU */
/*
* re-encode the actual ASN.1 length of the scopedPdu
*/
spdu_len = cp - spdu_hdr_e; /* length of scopedPdu minus ASN.1 headers */
spdu_buf_len = SNMP_MAX_MSG_SIZE;
if (asn_build_sequence(spdu_buf, &spdu_buf_len,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
spdu_len) == NULL)
return -1;
spdu_len = cp - spdu_buf; /* the length of the entire scopedPdu */
/*
* call the security module to possibly encrypt and authenticate the
* message - the entire message to transmitted on the wire is returned
*/
cp = NULL; *out_length = SNMP_MAX_MSG_SIZE;
DEBUGDUMPSECTION("send", "SM msgSecurityParameters");
sptr = find_sec_mod(pdu->securityModel);
if (sptr && sptr->encode_forward) {
struct snmp_secmod_outgoing_params parms;
parms.msgProcModel = pdu->msgParseModel;
parms.globalData = global_data;
parms.globalDataLen = global_data_len;
parms.maxMsgSize = SNMP_MAX_MSG_SIZE;
parms.secModel = pdu->securityModel;
parms.secEngineID = pdu->securityEngineID;
parms.secEngineIDLen = pdu->securityEngineIDLen;
parms.secName = pdu->securityName;
parms.secNameLen = pdu->securityNameLen;
parms.secLevel = pdu->securityLevel;
parms.scopedPdu = spdu_buf;
parms.scopedPduLen = spdu_len;
parms.secStateRef = pdu->securityStateRef;
parms.secParams = sec_params;
parms.secParamsLen = &sec_params_len;
parms.wholeMsg = &cp;
parms.wholeMsgLen = out_length;
parms.session = session;
parms.pdu = pdu;
result =
(*sptr->encode_forward)(&parms);
} else {
if (!sptr) {
snmp_log(LOG_ERR, "no such security service available: %d\n",
pdu->securityModel);
} else if (!sptr->encode_forward) {
snmp_log(LOG_ERR, "security service %d doesn't support forward out encoding.\n",
pdu->securityModel);
}
result = -1;
}
DEBUGINDENTLESS();
return result;
} /* end snmpv3_packet_build() */
/*
* Takes a session and a pdu and serializes the ASN PDU into the area
* pointed to by *pkt. *pkt_len is the size of the data area available.
* Returns the length of the completed packet in *offset. If any errors
* occur, -1 is returned. If all goes well, 0 is returned.
*/
static int
_snmp_build(u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_session *session, struct snmp_pdu *pdu)
{
u_char *h0, *h0e = 0, *h1;
u_char *cp;
size_t length, start_offset = *offset;
long version;
int rc = 0;
session->s_snmp_errno = 0;
session->s_errno = 0;
if (pdu->version == SNMP_VERSION_3) {
return snmpv3_build(pkt, pkt_len, offset, session, pdu);
}
switch (pdu->command) {
case SNMP_MSG_RESPONSE:
pdu->flags &= (~UCD_MSG_FLAG_EXPECT_RESPONSE);
/* Fallthrough */
case SNMP_MSG_GET:
case SNMP_MSG_GETNEXT:
case SNMP_MSG_SET:
/* all versions support these PDU types */
/* initialize defaulted PDU fields */
if (pdu->errstat == SNMP_DEFAULT_ERRSTAT)
pdu->errstat = 0;
if (pdu->errindex == SNMP_DEFAULT_ERRINDEX)
pdu->errindex = 0;
break;
case SNMP_MSG_TRAP2:
pdu->flags &= (~UCD_MSG_FLAG_EXPECT_RESPONSE);
/* Fallthrough */
case SNMP_MSG_INFORM:
/* not supported in SNMPv1 and SNMPsec */
if (pdu->version == SNMP_VERSION_1) {
session->s_snmp_errno = SNMPERR_V2_IN_V1;
return -1;
}
if (pdu->errstat == SNMP_DEFAULT_ERRSTAT)
pdu->errstat = 0;
if (pdu->errindex == SNMP_DEFAULT_ERRINDEX)
pdu->errindex = 0;
break;
case SNMP_MSG_GETBULK:
/* not supported in SNMPv1 and SNMPsec */
if (pdu->version == SNMP_VERSION_1) {
session->s_snmp_errno = SNMPERR_V2_IN_V1;
return -1;
}
if (pdu->max_repetitions < 0) {
session->s_snmp_errno = SNMPERR_BAD_REPETITIONS;
return -1;
}
if (pdu->non_repeaters < 0) {
session->s_snmp_errno = SNMPERR_BAD_REPEATERS;
return -1;
}
break;
case SNMP_MSG_TRAP:
/* *only* supported in SNMPv1 and SNMPsec */
if (pdu->version != SNMP_VERSION_1) {
session->s_snmp_errno = SNMPERR_V1_IN_V2;
return -1;
}
/* initialize defaulted Trap PDU fields */
pdu->reqid = 1; /* give a bogus non-error reqid for traps */
if (pdu->enterprise_length == SNMP_DEFAULT_ENTERPRISE_LENGTH){
pdu->enterprise = (oid *)malloc(sizeof(DEFAULT_ENTERPRISE));
if (pdu->enterprise == NULL) {
session->s_snmp_errno = SNMPERR_MALLOC;
return -1;
}
memmove(pdu->enterprise, DEFAULT_ENTERPRISE,
sizeof(DEFAULT_ENTERPRISE));
pdu->enterprise_length = sizeof(DEFAULT_ENTERPRISE)/sizeof(oid);
}
if (pdu->time == SNMP_DEFAULT_TIME)
pdu->time = DEFAULT_TIME;
/* don't expect a response */
pdu->flags &= (~UCD_MSG_FLAG_EXPECT_RESPONSE);
break;
case SNMP_MSG_REPORT: /* SNMPv3 only */
default:
session->s_snmp_errno = SNMPERR_UNKNOWN_PDU;
return -1;
}
/* save length */
length = *pkt_len;
/* setup administrative fields based on version */
/* build the message wrapper and all the administrative fields
upto the PDU sequence
(note that actual length of message will be inserted later) */
h0 = *pkt;
switch (pdu->version) {
case SNMP_VERSION_1:
case SNMP_VERSION_2c:
#ifdef NO_ZEROLENGTH_COMMUNITY
if (pdu->community_len == 0) {
if (session->community_len == 0) {
session->s_snmp_errno = SNMPERR_BAD_COMMUNITY;
return -1;
}
pdu->community = (u_char *)malloc(session->community_len);
if (pdu->community == NULL) {
session->s_snmp_errno = SNMPERR_MALLOC;
return -1;
}
memmove(pdu->community,
session->community, session->community_len);
pdu->community_len = session->community_len;
}
#else /* !NO_ZEROLENGTH_COMMUNITY */
if (pdu->community_len == 0 && pdu->command != SNMP_MSG_RESPONSE) {
/* copy session community exactly to pdu community */
if (0 == session->community_len) {
SNMP_FREE(pdu->community);
pdu->community = NULL;
} else if (pdu->community_len == session->community_len) {
memmove(pdu->community,
session->community, session->community_len);
} else {
SNMP_FREE(pdu->community);
pdu->community = (u_char *)malloc(session->community_len);
if (pdu->community == NULL) {
session->s_snmp_errno = SNMPERR_MALLOC;
return -1;
}
memmove(pdu->community,
session->community, session->community_len);
}
pdu->community_len = session->community_len;
}
#endif /* !NO_ZEROLENGTH_COMMUNITY */
DEBUGMSGTL(("snmp_send", "Building SNMPv%d message...\n",
(1 + pdu->version)));
#ifdef USE_REVERSE_ASNENCODING
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_REVERSE_ENCODE)) {
DEBUGPRINTPDUTYPE("send", pdu->command);
rc = snmp_pdu_realloc_rbuild(pkt, pkt_len, offset, pdu);
if (rc == 0) {
return -1;
}
DEBUGDUMPHEADER("send", "Community String");
rc = asn_realloc_rbuild_string(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OCTET_STR),
pdu->community, pdu->community_len);
DEBUGINDENTLESS();
if (rc == 0) {
return -1;
}
/* Store the version field. */
DEBUGDUMPHEADER("send", "SNMP Version Number");
version = pdu->version;
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *)&version, sizeof(version));
DEBUGINDENTLESS();
if (rc == 0) {
return -1;
}
/* Build the final sequence. */
if (pdu->version == SNMP_VERSION_1) {
DEBUGDUMPSECTION("send", "SNMPv1 Message");
} else {
DEBUGDUMPSECTION("send", "SNMPv2c Message");
}
rc = asn_realloc_rbuild_sequence(pkt, pkt_len, offset, 1,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
*offset - start_offset);
if (rc == 0) {
return -1;
}
return 0;
} else {
#endif /* USE_REVERSE_ASNENCODING */
/* Save current location and build SEQUENCE tag and length
placeholder for SNMP message sequence
(actual length will be inserted later) */
cp = asn_build_sequence(*pkt, pkt_len,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
0);
if (cp == NULL) {
return -1;
}
h0e = cp;
if (pdu->version == SNMP_VERSION_1) {
DEBUGDUMPSECTION("send", "SNMPv1 Message");
} else {
DEBUGDUMPSECTION("send", "SNMPv2c Message");
}
/* store the version field */
DEBUGDUMPHEADER("send", "SNMP Version Number");
version = pdu->version;
cp = asn_build_int(*pkt, pkt_len,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *)&version, sizeof(version));
DEBUGINDENTLESS();
if (cp == NULL)
return -1;
/* store the community string */
DEBUGDUMPHEADER("send", "Community String");
cp = asn_build_string(*pkt, pkt_len,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OCTET_STR),
pdu->community, pdu->community_len);
DEBUGINDENTLESS();
if (cp == NULL)
return -1;
break;
#ifdef USE_REVERSE_ASNENCODING
}
#endif /* USE_REVERSE_ASNENCODING */
case SNMP_VERSION_2p:
case SNMP_VERSION_sec:
case SNMP_VERSION_2u:
case SNMP_VERSION_2star:
default:
session->s_snmp_errno = SNMPERR_BAD_VERSION;
return -1;
}
h1 = cp;
DEBUGPRINTPDUTYPE("send", pdu->command);
cp = snmp_pdu_build(pdu, cp, pkt_len);
DEBUGINDENTADD(-4); /* return from entire v1/v2c message */
if (cp == NULL)
return -1;
/* insert the actual length of the message sequence */
switch (pdu->version) {
case SNMP_VERSION_1:
case SNMP_VERSION_2c:
asn_build_sequence(*pkt, &length,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
cp - h0e);
break;
case SNMP_VERSION_2p:
case SNMP_VERSION_sec:
case SNMP_VERSION_2u:
case SNMP_VERSION_2star:
default:
session->s_snmp_errno = SNMPERR_BAD_VERSION;
return -1;
}
*pkt_len = cp - *pkt;
return 0;
}
int
snmp_build(u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_session *pss, struct snmp_pdu *pdu)
{
int rc;
rc = _snmp_build(pkt, pkt_len, offset, pss, pdu);
if (rc) {
if (!pss->s_snmp_errno) {
pss->s_snmp_errno = SNMPERR_BAD_ASN1_BUILD;
}
SET_SNMP_ERROR(pss->s_snmp_errno);
rc = -1;
}
return rc;
}
/* on error, returns NULL (likely an encoding problem). */
u_char *
snmp_pdu_build (struct snmp_pdu *pdu, u_char *cp, size_t *out_length)
{
u_char *h1, *h1e, *h2, *h2e;
struct variable_list *vp;
size_t length;
length = *out_length;
/* Save current location and build PDU tag and length placeholder
(actual length will be inserted later) */
h1 = cp;
cp = asn_build_sequence(cp, out_length, (u_char)pdu->command, 0);
if (cp == NULL)
return NULL;
h1e = cp;
/* store fields in the PDU preceeding the variable-bindings sequence */
if (pdu->command != SNMP_MSG_TRAP){
/* PDU is not an SNMPv1 trap */
DEBUGDUMPHEADER("send", "request_id");
/* request id */
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->reqid, sizeof(pdu->reqid));
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
/* error status (getbulk non-repeaters) */
DEBUGDUMPHEADER("send", "error status");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->errstat, sizeof(pdu->errstat));
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
/* error index (getbulk max-repetitions) */
DEBUGDUMPHEADER("send", "error index");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->errindex, sizeof(pdu->errindex));
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
} else {
/* an SNMPv1 trap PDU */
/* enterprise */
DEBUGDUMPHEADER("send", "enterprise OBJID");
cp = asn_build_objid(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OBJECT_ID),
(oid *)pdu->enterprise, pdu->enterprise_length);
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
/* agent-addr */
DEBUGDUMPHEADER("send", "agent Address");
cp = asn_build_string(cp, out_length,
(u_char)(ASN_IPADDRESS | ASN_PRIMITIVE),
(u_char *)pdu->agent_addr, 4);
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
/* generic trap */
DEBUGDUMPHEADER("send", "generic trap number");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *)&pdu->trap_type, sizeof(pdu->trap_type));
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
/* specific trap */
DEBUGDUMPHEADER("send", "specific trap number");
cp = asn_build_int(cp, out_length,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *)&pdu->specific_type, sizeof(pdu->specific_type));
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
/* timestamp */
DEBUGDUMPHEADER("send", "timestamp");
cp = asn_build_unsigned_int(cp, out_length,
(u_char)(ASN_TIMETICKS | ASN_PRIMITIVE),
&pdu->time, sizeof(pdu->time));
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
}
/* Save current location and build SEQUENCE tag and length placeholder
for variable-bindings sequence
(actual length will be inserted later) */
h2 = cp;
cp = asn_build_sequence(cp, out_length,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
0);
if (cp == NULL)
return NULL;
h2e = cp;
/* Store variable-bindings */
DEBUGDUMPSECTION("send", "VarBindList");
for(vp = pdu->variables; vp; vp = vp->next_variable){
DEBUGDUMPSECTION("send", "VarBind");
cp = snmp_build_var_op(cp, vp->name, &vp->name_length, vp->type,
vp->val_len, (u_char *)vp->val.string,
out_length);
DEBUGINDENTLESS();
if (cp == NULL)
return NULL;
}
DEBUGINDENTLESS();
/* insert actual length of variable-bindings sequence */
asn_build_sequence(h2,&length,(u_char)(ASN_SEQUENCE|ASN_CONSTRUCTOR),cp-h2e);
/* insert actual length of PDU sequence */
asn_build_sequence(h1, &length, (u_char)pdu->command, cp - h1e);
return cp;
}
#ifdef USE_REVERSE_ASNENCODING
/* On error, returns 0 (likely an encoding problem). */
int
snmp_pdu_realloc_rbuild(u_char **pkt, size_t *pkt_len, size_t *offset,
struct snmp_pdu *pdu)
{
#ifndef VPCACHE_SIZE
#define VPCACHE_SIZE 50
#endif
struct variable_list *vpcache[VPCACHE_SIZE];
struct variable_list *vp, *tmpvp;
size_t start_offset = *offset;
int i, wrapped = 0, notdone, final, rc = 0;
DEBUGMSGTL(("snmp_pdu_realloc_rbuild", "starting\n"));
for(vp = pdu->variables, i = VPCACHE_SIZE-1; vp;
vp = vp->next_variable, i--) {
if (i < 0) {
wrapped = notdone = 1;
i = VPCACHE_SIZE-1;
DEBUGMSGTL(("snmp_pdu_realloc_rbuild", "wrapped\n"));
}
vpcache[i] = vp;
}
final = i + 1;
do {
for(i = final; i < VPCACHE_SIZE; i++) {
vp = vpcache[i];
DEBUGDUMPSECTION("send", "VarBind");
rc = snmp_realloc_rbuild_var_op(pkt, pkt_len, offset, 1,
vp->name, &vp->name_length, vp->type,
(u_char *)vp->val.string, vp->val_len);
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
}
DEBUGINDENTLESS();
if (wrapped) {
notdone = 1;
for(i = 0; i < final; i++) {
vp = vpcache[i];
DEBUGDUMPSECTION("send", "VarBind");
rc = snmp_realloc_rbuild_var_op(pkt, pkt_len, offset, 1,
vp->name, &vp->name_length, vp->type,
(u_char *)vp->val.string, vp->val_len);
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
}
if (final == 0) {
tmpvp = vpcache[VPCACHE_SIZE-1];
} else {
tmpvp = vpcache[final-1];
}
wrapped = 0;
for(vp = pdu->variables, i = VPCACHE_SIZE-1; vp && vp != tmpvp;
vp = vp->next_variable, i--) {
if (i < 0) {
wrapped = 1;
i = VPCACHE_SIZE-1;
DEBUGMSGTL(("snmp_pdu_realloc_rbuild","wrapped\n"));
}
vpcache[i] = vp;
}
final = i + 1;
} else {
notdone = 0;
}
} while (notdone);
/* Save current location and build SEQUENCE tag and length placeholder for
variable-bindings sequence (actual length will be inserted later). */
rc = asn_realloc_rbuild_sequence(pkt, pkt_len, offset, 1,
(u_char)(ASN_SEQUENCE | ASN_CONSTRUCTOR),
*offset - start_offset);
/* Store fields in the PDU preceeding the variable-bindings sequence. */
if (pdu->command != SNMP_MSG_TRAP) {
/* Error index (getbulk max-repetitions). */
DEBUGDUMPHEADER("send", "error index");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->errindex, sizeof(pdu->errindex));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* Error status (getbulk non-repeaters). */
DEBUGDUMPHEADER("send", "error status");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->errstat, sizeof(pdu->errstat));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* Request ID. */
DEBUGDUMPHEADER("send", "request_id");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
&pdu->reqid, sizeof(pdu->reqid));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
} else {
/* An SNMPv1 trap PDU. */
/* Timestamp. */
DEBUGDUMPHEADER("send", "timestamp");
rc = asn_realloc_rbuild_unsigned_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_TIMETICKS | ASN_PRIMITIVE),
&pdu->time, sizeof(pdu->time));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* Specific trap. */
DEBUGDUMPHEADER("send", "specific trap number");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *)&pdu->specific_type,
sizeof(pdu->specific_type));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* Generic trap. */
DEBUGDUMPHEADER("send", "generic trap number");
rc = asn_realloc_rbuild_int(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_INTEGER),
(long *)&pdu->trap_type, sizeof(pdu->trap_type));
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* Agent-addr. */
DEBUGDUMPHEADER("send", "agent Address");
rc = asn_realloc_rbuild_string(pkt, pkt_len, offset, 1,
(u_char)(ASN_IPADDRESS | ASN_PRIMITIVE),
(u_char *)pdu->agent_addr, 4);
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
/* Enterprise. */
DEBUGDUMPHEADER("send", "enterprise OBJID");
rc = asn_realloc_rbuild_objid(pkt, pkt_len, offset, 1,
(u_char)(ASN_UNIVERSAL | ASN_PRIMITIVE | ASN_OBJECT_ID),
(oid *)pdu->enterprise, pdu->enterprise_length);
DEBUGINDENTLESS();
if (rc == 0) {
return 0;
}
}
/* Build the PDU sequence. */
rc = asn_realloc_rbuild_sequence(pkt, pkt_len, offset, 1,
(u_char)pdu->command, *offset - start_offset);
return rc;
}
#endif /* USE_REVERSE_ASNENCODING */
/*
* Parses the packet received to determine version, either directly
* from packets version field or inferred from ASN.1 construct.
*/
static int
snmp_parse_version (u_char *data, size_t length)
{
u_char type;
long version = SNMPERR_BAD_VERSION;
data = asn_parse_sequence(data, &length, &type,
(ASN_SEQUENCE | ASN_CONSTRUCTOR), "version");
if (data) {
data = asn_parse_int(data, &length, &type, &version, sizeof(version));
if (!data || type != ASN_INTEGER) {
return SNMPERR_BAD_VERSION;
}
}
return version;
}
int
snmpv3_parse(
struct snmp_pdu *pdu,
u_char *data,
size_t *length,
u_char **after_header,
struct snmp_session *sess
)
{
u_char type, msg_flags;
long ver, msg_max_size, msg_sec_model;
size_t max_size_response;
u_char tmp_buf[SNMP_MAX_MSG_SIZE];
size_t tmp_buf_len;
u_char pdu_buf[SNMP_MAX_MSG_SIZE];
u_char *mallocbuf = NULL;
size_t pdu_buf_len = SNMP_MAX_MSG_SIZE;
u_char *sec_params;
u_char *msg_data;
u_char *cp;
size_t asn_len, msg_len;
int ret, ret_val;
struct snmp_secmod_def *sptr;
msg_data = data;
msg_len = *length;
/* message is an ASN.1 SEQUENCE */
DEBUGDUMPSECTION("recv", "SNMPv3 Message");
data = asn_parse_sequence(data, length, &type,
(ASN_SEQUENCE | ASN_CONSTRUCTOR), "message");
if (data == NULL) {
/* error msg detail is set */
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
DEBUGINDENTLESS();
return SNMPERR_ASN_PARSE_ERR;
}
/* parse msgVersion */
DEBUGDUMPHEADER("recv", "SNMP Version Number");
data = asn_parse_int(data, length, &type, &ver, sizeof(ver));
DEBUGINDENTLESS();
if (data == NULL) {
ERROR_MSG("bad parse of version");
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
DEBUGINDENTLESS();
return SNMPERR_ASN_PARSE_ERR;
}
pdu->version = ver;
/* parse msgGlobalData sequence */
cp = data;
asn_len = *length;
DEBUGDUMPSECTION("recv", "msgGlobalData");
data = asn_parse_sequence(data, &asn_len, &type,
(ASN_SEQUENCE | ASN_CONSTRUCTOR), "msgGlobalData");
if (data == NULL) {
/* error msg detail is set */
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
DEBUGINDENTADD(-4);
return SNMPERR_ASN_PARSE_ERR;
}
*length -= data - cp; /* subtract off the length of the header */
/* msgID */
DEBUGDUMPHEADER("recv", "msgID");
data = asn_parse_int(data, length, &type, &pdu->msgid, sizeof(pdu->msgid));
DEBUGINDENTLESS();
if (data == NULL || type != ASN_INTEGER) {
ERROR_MSG("error parsing msgID");
DEBUGINDENTADD(-4);
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
return SNMPERR_ASN_PARSE_ERR;
}
/* msgMaxSize */
DEBUGDUMPHEADER("recv", "msgMaxSize");
data = asn_parse_int(data, length, &type, &msg_max_size,
sizeof(msg_max_size));
DEBUGINDENTLESS();
if (data == NULL || type != ASN_INTEGER) {
ERROR_MSG("error parsing msgMaxSize");
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
DEBUGINDENTADD(-4);
return SNMPERR_ASN_PARSE_ERR;
}
/* Check the msgMaxSize we received is a legal value. If not, then clamp
it in the appropriate direction and carry on anyway (also logging the
error). I'm not sure this is the correct behaviour, but it seems
reasonable to me. Note we store the msgMaxSize on a per-session basis
which also seems reasonable; it could vary from PDU to PDU but that
would be strange (also since we deal with a PDU at a time, it wouldn't
make any difference to our responses, if any). */
if (msg_max_size < 484) {
snmp_log(LOG_ERR, "rx bad msgMaxSize (%lu < 484); using 484.\n",
msg_max_size);
sess->sndMsgMaxSize = 484;
} else if (msg_max_size > 0x7fffffff) {
snmp_log(LOG_ERR, "rx bad msgMaxSize (%lu > 2^31 - 1); using 2^31 - 1.\n",
msg_max_size);
sess->sndMsgMaxSize = 0x7fffffff;
} else {
DEBUGMSGTL(("snmpv3_parse", "msgMaxSize %lu received\n", msg_max_size));
sess->sndMsgMaxSize = msg_max_size;
}
/* msgFlags */
tmp_buf_len = SNMP_MAX_MSG_SIZE;
DEBUGDUMPHEADER("recv", "msgFlags");
data = asn_parse_string(data, length, &type, tmp_buf, &tmp_buf_len);
DEBUGINDENTLESS();
if (data == NULL || type != ASN_OCTET_STR || tmp_buf_len != 1) {
ERROR_MSG("error parsing msgFlags");
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
DEBUGINDENTADD(-4);
return SNMPERR_ASN_PARSE_ERR;
}
msg_flags = *tmp_buf;
if (msg_flags & SNMP_MSG_FLAG_RPRT_BIT)
pdu->flags |= SNMP_MSG_FLAG_RPRT_BIT;
else
pdu->flags &= (~SNMP_MSG_FLAG_RPRT_BIT);
/* msgSecurityModel */
DEBUGDUMPHEADER("recv", "msgSecurityModel");
data = asn_parse_int(data, length, &type, &msg_sec_model,
sizeof(msg_sec_model));
DEBUGINDENTADD(-4); /* return from global data indent */
if (data == NULL || type != ASN_INTEGER ||
msg_sec_model < 0 || msg_sec_model > 0x7fffffff) {
ERROR_MSG("error parsing msgSecurityModel");
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
DEBUGINDENTLESS();
return SNMPERR_ASN_PARSE_ERR;
}
sptr = find_sec_mod(msg_sec_model);
if (!sptr) {
snmp_log(LOG_WARNING, "unknown security model: %d\n", msg_sec_model);
snmp_increment_statistic(STAT_SNMPUNKNOWNSECURITYMODELS);
DEBUGINDENTLESS();
return SNMPERR_UNKNOWN_SEC_MODEL;
}
pdu->securityModel = msg_sec_model;
if (msg_flags & SNMP_MSG_FLAG_PRIV_BIT &&
!(msg_flags & SNMP_MSG_FLAG_AUTH_BIT)) {
ERROR_MSG("invalid message, illegal msgFlags");
snmp_increment_statistic(STAT_SNMPINVALIDMSGS);
DEBUGINDENTLESS();
return SNMPERR_INVALID_MSG;
}
pdu->securityLevel = ( (msg_flags & SNMP_MSG_FLAG_AUTH_BIT)
? ( (msg_flags & SNMP_MSG_FLAG_PRIV_BIT)
? SNMP_SEC_LEVEL_AUTHPRIV
: SNMP_SEC_LEVEL_AUTHNOPRIV )
: SNMP_SEC_LEVEL_NOAUTH );
/* end of msgGlobalData */
/* securtityParameters OCTET STRING begins after msgGlobalData */
sec_params = data;
pdu->contextEngineID = (u_char *)calloc(1,SNMP_MAX_ENG_SIZE);
pdu->contextEngineIDLen = SNMP_MAX_ENG_SIZE;
pdu->securityEngineID = (u_char *)calloc(1,SNMP_MAX_ENG_SIZE);
pdu->securityEngineIDLen = SNMP_MAX_ENG_SIZE;
pdu->securityName = (char *)calloc(1,SNMP_MAX_SEC_NAME_SIZE);
pdu->securityNameLen = SNMP_MAX_SEC_NAME_SIZE;
if ((pdu->securityName == NULL) ||
(pdu->securityEngineID == NULL) ||
(pdu->contextEngineID == NULL))
{
return SNMPERR_MALLOC;
}
if (pdu_buf_len < msg_len && pdu->securityLevel == SNMP_SEC_LEVEL_AUTHPRIV) {
/* space needed is larger than we have in the default buffer */
mallocbuf = (u_char *) calloc(1, msg_len);
pdu_buf_len = msg_len;
cp = mallocbuf;
} else {
memset(pdu_buf, 0, pdu_buf_len);
cp = pdu_buf;
}
DEBUGDUMPSECTION("recv", "SM msgSecurityParameters");
if (sptr->decode) {
struct snmp_secmod_incoming_params parms;
parms.msgProcModel = pdu->msgParseModel;
parms.maxMsgSize = msg_max_size;
parms.secParams = sec_params;
parms.secModel = msg_sec_model;
parms.secLevel = pdu->securityLevel;
parms.wholeMsg = msg_data;
parms.wholeMsgLen = msg_len;
parms.secEngineID = pdu->securityEngineID;
parms.secEngineIDLen = &pdu->securityEngineIDLen;
parms.secName = pdu->securityName;
parms.secNameLen = &pdu->securityNameLen;
parms.scopedPdu = &cp;
parms.scopedPduLen = &pdu_buf_len;
parms.maxSizeResponse = &max_size_response;
parms.secStateRef = &pdu->securityStateRef;
parms.sess = sess;
parms.pdu = pdu;
parms.msg_flags = msg_flags;
ret_val =
(*sptr->decode)(&parms);
} else {
DEBUGINDENTLESS();
snmp_log(LOG_WARNING, "security service %d can't decode packets\n",
msg_sec_model);
return(-1);
}
if (ret_val != SNMPERR_SUCCESS) {
DEBUGDUMPSECTION("recv", "ScopedPDU");
/* parse as much as possible */
if (cp) {
cp = snmpv3_scopedPDU_parse(pdu, cp, &pdu_buf_len);
}
if (cp) {
DEBUGPRINTPDUTYPE("recv", *cp);
snmp_pdu_parse(pdu, cp, &pdu_buf_len);
DEBUGINDENTADD(-8);
} else {
DEBUGINDENTADD(-4);
}
if (mallocbuf) {
free(mallocbuf);
}
return ret_val;
}
/* parse plaintext ScopedPDU sequence */
*length = pdu_buf_len;
DEBUGDUMPSECTION("recv", "ScopedPDU");
data = snmpv3_scopedPDU_parse(pdu, cp, length);
if (data == NULL) {
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
DEBUGINDENTADD(-4);
if (mallocbuf)
free(mallocbuf);
return SNMPERR_ASN_PARSE_ERR;
}
/* parse the PDU. */
if (after_header != NULL) {
*after_header = data;
tmp_buf_len = *length;
}
DEBUGPRINTPDUTYPE("recv", *data);
ret = snmp_pdu_parse(pdu, data, length);
DEBUGINDENTADD(-8);
if (after_header != NULL) {
*length = tmp_buf_len;
}
if (ret != SNMPERR_SUCCESS) {
ERROR_MSG("error parsing PDU");
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
if (mallocbuf)
free(mallocbuf);
return SNMPERR_ASN_PARSE_ERR;
}
if (mallocbuf)
free(mallocbuf);
return SNMPERR_SUCCESS;
} /* end snmpv3_parse() */
#define ERROR_STAT_LENGTH 11
int
snmpv3_make_report(struct snmp_pdu *pdu, int error)
{
long ltmp;
static oid unknownSecurityLevel[] = {1,3,6,1,6,3,15,1,1,1,0};
static oid notInTimeWindow[] = {1,3,6,1,6,3,15,1,1,2,0};
static oid unknownUserName[] = {1,3,6,1,6,3,15,1,1,3,0};
static oid unknownEngineID[] = {1,3,6,1,6,3,15,1,1,4,0};
static oid wrongDigest[] = {1,3,6,1,6,3,15,1,1,5,0};
static oid decryptionError[] = {1,3,6,1,6,3,15,1,1,6,0};
oid *err_var;
int err_var_len;
int stat_ind;
struct snmp_secmod_def *sptr;
switch (error) {
case SNMPERR_USM_UNKNOWNENGINEID:
stat_ind = STAT_USMSTATSUNKNOWNENGINEIDS;
err_var = unknownEngineID;
err_var_len = ERROR_STAT_LENGTH;
break;
case SNMPERR_USM_UNKNOWNSECURITYNAME:
stat_ind = STAT_USMSTATSUNKNOWNUSERNAMES;
err_var = unknownUserName;
err_var_len = ERROR_STAT_LENGTH;
break;
case SNMPERR_USM_UNSUPPORTEDSECURITYLEVEL:
stat_ind = STAT_USMSTATSUNSUPPORTEDSECLEVELS;
err_var = unknownSecurityLevel;
err_var_len = ERROR_STAT_LENGTH;
break;
case SNMPERR_USM_AUTHENTICATIONFAILURE:
stat_ind = STAT_USMSTATSWRONGDIGESTS;
err_var = wrongDigest;
err_var_len = ERROR_STAT_LENGTH;
break;
case SNMPERR_USM_NOTINTIMEWINDOW:
stat_ind = STAT_USMSTATSNOTINTIMEWINDOWS;
err_var = notInTimeWindow;
err_var_len = ERROR_STAT_LENGTH;
break;
case SNMPERR_USM_DECRYPTIONERROR:
stat_ind = STAT_USMSTATSDECRYPTIONERRORS;
err_var = decryptionError;
err_var_len = ERROR_STAT_LENGTH;
break;
default:
return SNMPERR_GENERR;
}
snmp_free_varbind(pdu->variables); /* free the current varbind */
pdu->variables = NULL;
SNMP_FREE(pdu->securityEngineID);
pdu->securityEngineID = snmpv3_generate_engineID(&pdu->securityEngineIDLen);
SNMP_FREE(pdu->contextEngineID);
pdu->contextEngineID = snmpv3_generate_engineID(&pdu->contextEngineIDLen);
pdu->command = SNMP_MSG_REPORT;
pdu->errstat = 0;
pdu->errindex = 0;
SNMP_FREE(pdu->contextName);
pdu->contextName = strdup("");
pdu->contextNameLen = strlen(pdu->contextName);
/* reports shouldn't cache previous data. */
/* FIX - yes they should but USM needs to follow new EoP to determine
which cached values to use
*/
if (pdu->securityStateRef) {
sptr = find_sec_mod(pdu->securityModel);
if (sptr) {
if (sptr->pdu_free_state_ref) {
(*sptr->pdu_free_state_ref)(pdu->securityStateRef);
} else {
snmp_log(LOG_ERR,
"Security Model %d can't free state references\n",
pdu->securityModel);
}
} else {
snmp_log(LOG_ERR, "Can't find security model to free ptr: %d\n",
pdu->securityModel);
}
pdu->securityStateRef = NULL;
}
if (error == SNMPERR_USM_NOTINTIMEWINDOW) {
pdu->securityLevel = SNMP_SEC_LEVEL_AUTHNOPRIV;
} else {
pdu->securityLevel = SNMP_SEC_LEVEL_NOAUTH;
}
/* find the appropriate error counter */
ltmp = snmp_get_statistic(stat_ind);
/* return the appropriate error counter */
snmp_pdu_add_variable(pdu, err_var, err_var_len,
ASN_COUNTER, (u_char *) &ltmp, sizeof(ltmp));
return SNMPERR_SUCCESS;
} /* end snmpv3_make_report() */
int
snmpv3_get_report_type(struct snmp_pdu *pdu)
{
static oid snmpMPDStats[] = {1,3,6,1,6,3,11,2,1};
static oid usmStats[] = {1,3,6,1,6,3,15,1,1};
struct variable_list *vp;
int rpt_type = SNMPERR_UNKNOWN_REPORT;
if (pdu == NULL || pdu->variables == NULL) return rpt_type;
vp = pdu->variables;
if (vp->name_length == REPORT_STATS_LEN+2) {
if (memcmp(snmpMPDStats, vp->name, REPORT_STATS_LEN*sizeof(oid)) == 0) {
switch (vp->name[REPORT_STATS_LEN]) {
case REPORT_snmpUnknownSecurityModels_NUM:
rpt_type = SNMPERR_UNKNOWN_SEC_MODEL;
break;
case REPORT_snmpInvalidMsgs_NUM:
rpt_type = SNMPERR_INVALID_MSG;
break;
}
} else if (memcmp(usmStats, vp->name, REPORT_STATS_LEN*sizeof(oid)) == 0) {
switch (vp->name[REPORT_STATS_LEN]) {
case REPORT_usmStatsUnsupportedSecLevels_NUM:
rpt_type = SNMPERR_UNSUPPORTED_SEC_LEVEL;
break;
case REPORT_usmStatsNotInTimeWindows_NUM:
rpt_type = SNMPERR_NOT_IN_TIME_WINDOW;
break;
case REPORT_usmStatsUnknownUserNames_NUM:
rpt_type = SNMPERR_UNKNOWN_USER_NAME;
break;
case REPORT_usmStatsUnknownEngineIDs_NUM:
rpt_type = SNMPERR_UNKNOWN_ENG_ID;
break;
case REPORT_usmStatsWrongDigests_NUM:
rpt_type = SNMPERR_AUTHENTICATION_FAILURE;
break;
case REPORT_usmStatsDecryptionErrors_NUM:
rpt_type = SNMPERR_DECRYPTION_ERR;
break;
}
}
}
DEBUGMSGTL(("report", "Report type: %d\n", rpt_type));
return rpt_type;
}
/*
* Parses the packet received on the input session, and places the data into
* the input pdu. length is the length of the input packet.
* If any errors are encountered, -1 or USM error is returned.
* Otherwise, a 0 is returned.
*/
static int
_snmp_parse(void * sessp,
struct snmp_session *session,
struct snmp_pdu *pdu,
u_char *data,
size_t length)
{
u_char community[COMMUNITY_MAX_LEN];
size_t community_length = COMMUNITY_MAX_LEN;
int result = -1;
session->s_snmp_errno = 0;
session->s_errno = 0;
/* Ensure all incoming PDUs have a unique means of identification
(This is not restricted to AgentX handling,
though that is where the need becomes visible) */
pdu->transid = snmp_get_next_transid();
if (session->version != SNMP_DEFAULT_VERSION) {
pdu->version = session->version;
} else {
pdu->version = snmp_parse_version(data,length);
}
switch (pdu->version) {
case SNMP_VERSION_1:
case SNMP_VERSION_2c:
DEBUGMSGTL(("snmp_api", "Parsing SNMPv%d message...\n",
(1 + pdu->version)));
/* authenticates message and returns length if valid */
if (pdu->version == SNMP_VERSION_1) {
DEBUGDUMPSECTION("recv", "SNMPv1 message\n");
} else {
DEBUGDUMPSECTION("recv", "SNMPv2c message\n");
}
data = snmp_comstr_parse(data, &length,
community, &community_length,
&pdu->version);
if (data == NULL)
return -1;
if (pdu->version != session->version &&
session->version != SNMP_DEFAULT_VERSION) {
session->s_snmp_errno = SNMPERR_BAD_VERSION;
return -1;
}
/* maybe get the community string. */
pdu->securityLevel = SNMP_SEC_LEVEL_NOAUTH;
pdu->securityModel = (pdu->version == SNMP_VERSION_1) ?
SNMP_SEC_MODEL_SNMPv1 : SNMP_SEC_MODEL_SNMPv2c;
SNMP_FREE(pdu->community);
pdu->community_len = 0;
pdu->community = (u_char *)0;
if (community_length) {
pdu->community_len = community_length;
pdu->community = (u_char *)malloc(community_length);
if (pdu->community == NULL) {
session->s_snmp_errno = SNMPERR_MALLOC;
return -1;
}
memmove(pdu->community, community, community_length);
}
if (session->authenticator) {
data = session->authenticator(data, &length,
community, community_length);
if (data == NULL) {
session->s_snmp_errno = SNMPERR_AUTHENTICATION_FAILURE;
return -1;
}
}
DEBUGDUMPSECTION("recv","PDU");
result = snmp_pdu_parse(pdu, data, &length);
if (result < 0) {
/* This indicates a parse error. */
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
}
DEBUGINDENTADD(-6);
break;
case SNMP_VERSION_3:
result = snmpv3_parse(pdu, data, &length, NULL, session);
DEBUGMSGTL(("snmp_parse",
"Parsed SNMPv3 message (secName:%s, secLevel:%s): %s\n",
pdu->securityName, secLevelName[pdu->securityLevel],
snmp_api_errstring(result)));
if (result) {
if (!sessp) {
session->s_snmp_errno = result;
} else {
/* handle reportable errors */
switch (result) {
case SNMPERR_USM_UNKNOWNENGINEID:
case SNMPERR_USM_UNKNOWNSECURITYNAME:
case SNMPERR_USM_UNSUPPORTEDSECURITYLEVEL:
case SNMPERR_USM_AUTHENTICATIONFAILURE:
case SNMPERR_USM_NOTINTIMEWINDOW:
case SNMPERR_USM_DECRYPTIONERROR:
if (SNMP_CMD_CONFIRMED(pdu->command) ||
(pdu->command == 0 && (pdu->flags & SNMP_MSG_FLAG_RPRT_BIT))) {
struct snmp_pdu *pdu2;
int flags = pdu->flags;
pdu->flags |= UCD_MSG_FLAG_FORCE_PDU_COPY;
pdu2 = snmp_clone_pdu(pdu);
pdu->flags = pdu2->flags = flags;
snmpv3_make_report(pdu2, result);
if (0 == snmp_sess_send(sessp, pdu2)) {
snmp_free_pdu(pdu2);
/* TODO: indicate error */
}
}
break;
default:
session->s_snmp_errno = result;
break;
}
}
}
break;
case SNMPERR_BAD_VERSION:
ERROR_MSG("error parsing snmp message version");
snmp_increment_statistic(STAT_SNMPINASNPARSEERRS);
session->s_snmp_errno = SNMPERR_BAD_VERSION;
break;
case SNMP_VERSION_sec:
case SNMP_VERSION_2u:
case SNMP_VERSION_2star:
case SNMP_VERSION_2p:
default:
ERROR_MSG("unsupported snmp message version");
snmp_increment_statistic(STAT_SNMPINBADVERSIONS);
session->s_snmp_errno = SNMPERR_BAD_VERSION;
break;
}
return result;
}
static int
snmp_parse(void *sessp,
struct snmp_session *pss,
struct snmp_pdu *pdu,
u_char *data,
size_t length)
{
int rc;
rc = _snmp_parse(sessp, pss, pdu, data, length);
if (rc) {
if (!pss->s_snmp_errno) {
pss->s_snmp_errno = SNMPERR_BAD_PARSE;
}
SET_SNMP_ERROR(pss->s_snmp_errno);
}
return rc;
}
int
snmp_pdu_parse(struct snmp_pdu *pdu, u_char *data, size_t *length)
{
u_char type;
u_char msg_type;
u_char *var_val;
int badtype;
size_t len;
size_t four;
struct variable_list *vp = NULL;
oid objid[MAX_OID_LEN];
badtype = 0;
/* Get the PDU type */
data = asn_parse_header(data, length, &msg_type);
if (data == NULL)
return -1;
pdu->command = msg_type;
pdu->flags &= (~UCD_MSG_FLAG_RESPONSE_PDU);
/* get the fields in the PDU preceeding the variable-bindings sequence */
switch (pdu->command) {
case SNMP_MSG_TRAP:
/* enterprise */
pdu->enterprise_length = MAX_OID_LEN;
data = asn_parse_objid(data, length, &type, objid,
&pdu->enterprise_length);
if (data == NULL)
return -1;
pdu->enterprise = (oid *)malloc(pdu->enterprise_length * sizeof(oid));
if (pdu->enterprise == NULL) {
return -1;
}
memmove(pdu->enterprise, objid, pdu->enterprise_length * sizeof(oid));
/* agent-addr */
four = 4;
data = asn_parse_string(data, length, &type,
(u_char *)pdu->agent_addr, &four);
if (data == NULL)
return -1;
/* generic trap */
data = asn_parse_int(data, length, &type, (long *)&pdu->trap_type,
sizeof(pdu->trap_type));
if (data == NULL)
return -1;
/* specific trap */
data = asn_parse_int(data, length, &type, (long *)&pdu->specific_type,
sizeof(pdu->specific_type));
if (data == NULL)
return -1;
/* timestamp */
data = asn_parse_unsigned_int(data, length, &type, &pdu->time,
sizeof(pdu->time));
if (data == NULL)
return -1;
break;
case SNMP_MSG_RESPONSE:
case SNMP_MSG_REPORT:
pdu->flags |= UCD_MSG_FLAG_RESPONSE_PDU;
/* fallthrough */
default:
/* PDU is not an SNMPv1 TRAP */
/* request id */
DEBUGDUMPHEADER("recv", "request_id");
data = asn_parse_int(data, length, &type, &pdu->reqid,
sizeof(pdu->reqid));
DEBUGINDENTLESS();
if (data == NULL) {
return -1;
}
/* error status (getbulk non-repeaters) */
DEBUGDUMPHEADER("recv", "error status");
data = asn_parse_int(data, length, &type, &pdu->errstat,
sizeof(pdu->errstat));
DEBUGINDENTLESS();
if (data == NULL) {
return -1;
}
/* error index (getbulk max-repetitions) */
DEBUGDUMPHEADER("recv", "error index");
data = asn_parse_int(data, length, &type, &pdu->errindex,
sizeof(pdu->errindex));
DEBUGINDENTLESS();
if (data == NULL) {
return -1;
}
}
/* get header for variable-bindings sequence */
DEBUGDUMPSECTION("recv", "VarBindList");
data = asn_parse_sequence(data, length, &type,
(ASN_SEQUENCE | ASN_CONSTRUCTOR), "varbinds");
if (data == NULL)
return -1;
/* get each varBind sequence */
while((int)*length > 0) {
struct variable_list *vptemp;
vptemp = (struct variable_list *)malloc(sizeof(*vptemp));
if (0 == vptemp) {
return -1;
}
if (0 == vp){
pdu->variables = vptemp;
} else {
vp->next_variable = vptemp;
}
vp = vptemp;
vp->next_variable = NULL;
vp->val.string = NULL;
vp->name_length = MAX_OID_LEN;
vp->name = 0;
vp->index = 0;
vp->data = 0;
vp->dataFreeHook = 0;
DEBUGDUMPSECTION("recv", "VarBind");
data = snmp_parse_var_op(data, objid, &vp->name_length, &vp->type,
&vp->val_len, &var_val, length);
if (data == NULL)
return -1;
if (snmp_set_var_objid(vp, objid, vp->name_length))
return -1;
len = MAX_PACKET_LENGTH;
DEBUGDUMPHEADER("recv", "Value");
switch((short)vp->type){
case ASN_INTEGER:
vp->val.integer = (long *)vp->buf;
vp->val_len = sizeof(long);
asn_parse_int(var_val, &len, &vp->type,
(long *)vp->val.integer,
sizeof(vp->val.integer));
break;
case ASN_COUNTER:
case ASN_GAUGE:
case ASN_TIMETICKS:
case ASN_UINTEGER:
vp->val.integer = (long *)vp->buf;
vp->val_len = sizeof(u_long);
asn_parse_unsigned_int(var_val, &len, &vp->type,
(u_long *)vp->val.integer,
vp->val_len);
break;
#ifdef OPAQUE_SPECIAL_TYPES
case ASN_OPAQUE_COUNTER64:
case ASN_OPAQUE_U64:
#endif /* OPAQUE_SPECIAL_TYPES */
case ASN_COUNTER64:
vp->val.counter64 = (struct counter64 *)vp->buf;
vp->val_len = sizeof(struct counter64);
asn_parse_unsigned_int64(var_val, &len, &vp->type,
(struct counter64 *)vp->val.counter64,
vp->val_len);
break;
#ifdef OPAQUE_SPECIAL_TYPES
case ASN_OPAQUE_FLOAT:
vp->val.floatVal = (float *)vp->buf;
vp->val_len = sizeof(float);
asn_parse_float(var_val, &len, &vp->type,
vp->val.floatVal,
vp->val_len);
break;
case ASN_OPAQUE_DOUBLE:
vp->val.doubleVal = (double *)vp->buf;
vp->val_len = sizeof(double);
asn_parse_double(var_val, &len, &vp->type,
vp->val.doubleVal,
vp->val_len);
break;
case ASN_OPAQUE_I64:
vp->val.counter64 = (struct counter64 *)vp->buf;
vp->val_len = sizeof(struct counter64);
asn_parse_signed_int64(var_val, &len, &vp->type,
(struct counter64 *)vp->val.counter64,
sizeof(*vp->val.counter64));
break;
#endif /* OPAQUE_SPECIAL_TYPES */
case ASN_OCTET_STR:
case ASN_IPADDRESS:
case ASN_OPAQUE:
case ASN_NSAP:
if (vp->val_len < sizeof(vp->buf)){
vp->val.string = (u_char *)vp->buf;
} else {
vp->val.string = (u_char *)malloc(vp->val_len);
}
if (vp->val.string == NULL) {
return -1;
}
asn_parse_string(var_val ,&len, &vp->type, vp->val.string,
&vp->val_len);
break;
case ASN_OBJECT_ID:
vp->val_len = MAX_OID_LEN;
asn_parse_objid(var_val, &len, &vp->type, objid, &vp->val_len);
vp->val_len *= sizeof(oid);
vp->val.objid = (oid *)malloc(vp->val_len);
if (vp->val.objid == NULL) {
return -1;
}
memmove(vp->val.objid, objid, vp->val_len);
break;
case SNMP_NOSUCHOBJECT:
case SNMP_NOSUCHINSTANCE:
case SNMP_ENDOFMIBVIEW:
case ASN_NULL:
break;
case ASN_BIT_STR:
vp->val.bitstring = (u_char *)malloc(vp->val_len);
if (vp->val.bitstring == NULL) {
return -1;
}
asn_parse_bitstring(var_val, &len, &vp->type,
vp->val.bitstring, &vp->val_len);
break;
default:
snmp_log(LOG_ERR,"bad type returned (%x)\n", vp->type);
badtype = 1;
break;
}
DEBUGINDENTADD(-4);
}
return badtype;
}
/* snmp v3 utility function to parse into the scopedPdu. stores contextName
and contextEngineID in pdu struct. Also stores pdu->command (handy for
Report generation).
returns pointer to begining of PDU or NULL on error.
*/
u_char *
snmpv3_scopedPDU_parse(struct snmp_pdu *pdu,
u_char *cp,
size_t *length)
{
u_char tmp_buf[SNMP_MAX_MSG_SIZE];
size_t tmp_buf_len;
u_char type;
size_t asn_len;
u_char* data;
pdu->command = 0; /* initialize so we know if it got parsed */
asn_len = *length;
data = asn_parse_sequence(cp, &asn_len, &type,
(ASN_SEQUENCE | ASN_CONSTRUCTOR), "plaintext scopedPDU");
if (data == NULL){
return NULL;
}
*length -= data - cp;
/* contextEngineID from scopedPdu */
DEBUGDUMPHEADER("recv", "contextEngineID");
data = asn_parse_string(data, length, &type, pdu->contextEngineID,
&pdu->contextEngineIDLen);
DEBUGINDENTLESS();
if (data == NULL) {
ERROR_MSG("error parsing contextEngineID from scopedPdu");
return NULL;
}
/* check that it agrees with engineID returned from USM above
* only a warning because this could be legal if we are a proxy
*/
if (pdu->securityEngineIDLen != pdu->contextEngineIDLen ||
memcmp(pdu->securityEngineID, pdu->contextEngineID,
pdu->securityEngineIDLen) != 0) {
DEBUGMSGTL(("scopedPDU_parse",
"inconsistent engineID information in message\n"));
}
/* parse contextName from scopedPdu
*/
tmp_buf_len = SNMP_MAX_CONTEXT_SIZE;
DEBUGDUMPHEADER("recv", "contextName");
data = asn_parse_string(data, length, &type, tmp_buf, &tmp_buf_len);
DEBUGINDENTLESS();
if (data == NULL) {
ERROR_MSG("error parsing contextName from scopedPdu");
return NULL;
}
if (tmp_buf_len) {
pdu->contextName = (char *)malloc(tmp_buf_len);
memmove(pdu->contextName, tmp_buf, tmp_buf_len);
pdu->contextNameLen = tmp_buf_len;
} else {
pdu->contextName = strdup("");
pdu->contextNameLen = 0;
}
if (pdu->contextName == NULL) {
ERROR_MSG("error copying contextName from scopedPdu");
return NULL;
}
/* Get the PDU type */
asn_len = *length;
cp = asn_parse_header(data, &asn_len, &type);
if (cp == NULL)
return NULL;
pdu->command = type;
return data;
}
/*
* These functions send PDUs using an active session:
* snmp_send - traditional API, no callback
* snmp_async_send - traditional API, with callback
* snmp_sess_send - single session API, no callback
* snmp_sess_async_send - single session API, with callback
*
* Call snmp_build to create a serialized packet (the pdu).
* If necessary, set some of the pdu data from the
* session defaults.
* If there is an expected response for this PDU,
* queue a corresponding request on the list
* of outstanding requests for this session,
* and store the callback vectors in the request.
*
* Send the pdu to the target identified by this session.
* Return on success:
* The request id of the pdu is returned, and the pdu is freed.
* Return on failure:
* Zero (0) is returned.
* The caller must call snmp_free_pdu if 0 is returned.
*/
int
snmp_send(struct snmp_session *session,
struct snmp_pdu *pdu)
{
return snmp_async_send(session, pdu, NULL, NULL);
}
int
snmp_sess_send(void *sessp,
struct snmp_pdu *pdu)
{
return snmp_sess_async_send(sessp, pdu, NULL, NULL);
}
int
snmp_async_send(struct snmp_session *session,
struct snmp_pdu *pdu,
snmp_callback callback,
void *cb_data)
{
void *sessp = snmp_sess_pointer(session);
return snmp_sess_async_send(sessp, pdu, callback, cb_data);
}
static int
_sess_async_send(void *sessp,
struct snmp_pdu *pdu,
snmp_callback callback,
void *cb_data)
{
struct session_list *slp = (struct session_list *)sessp;
struct snmp_session *session;
struct snmp_internal_session *isp;
snmp_transport *transport = NULL;
u_char *pktbuf = NULL, *packet = NULL;
size_t pktbuf_len = 0, offset = 0, length = 0;
int result;
long reqid;
if (slp == NULL) {
return 0;
} else {
session = slp->session;
isp = slp->internal;
transport = slp->transport;
if (!session || !isp || !transport) {
DEBUGMSGTL(("sess_async_send","send fail: closing...\n"));
return 0;
}
}
if (pdu == NULL) {
session->s_snmp_errno = SNMPERR_NULL_PDU;
return 0;
}
if ((pktbuf = malloc(2048)) == NULL) {
DEBUGMSGTL(("sess_async_send", "couldn't malloc initial packet buffer\n"));
session->s_snmp_errno = SNMPERR_MALLOC;
return 0;
} else {
pktbuf_len = 2048;
}
session->s_snmp_errno = 0;
session->s_errno = 0;
#if TEMPORARILY_DISABLED
/*
* NULL variable are allowed in certain PDU types.
* In particular, SNMPv3 engineID probes are of this form.
* There is an internal PDU flag to indicate that this
* is acceptable, but until the construction of engineID
* probes can be amended to set this flag, we'll simply
* skip this test altogether.
*/
if (pdu->variables == NULL) {
switch (pdu->command) {
case SNMP_MSG_GET:
case SNMP_MSG_SET:
case SNMP_MSG_GETNEXT:
case SNMP_MSG_GETBULK:
case SNMP_MSG_RESPONSE:
case SNMP_MSG_TRAP2:
case SNMP_MSG_REPORT:
case SNMP_MSG_INFORM:
session->s_snmp_errno = snmp_errno = SNMPERR_NO_VARS;
return 0;
case SNMP_MSG_TRAP:
break;
}
}
#endif
pdu->flags |= UCD_MSG_FLAG_EXPECT_RESPONSE;
/* Check/setup the version. */
if (pdu->version == SNMP_DEFAULT_VERSION) {
if (session->version == SNMP_DEFAULT_VERSION) {
session->s_snmp_errno = SNMPERR_BAD_VERSION;
free(pktbuf);
return 0;
}
pdu->version = session->version;
} else if (session->version == SNMP_DEFAULT_VERSION) {
/* It's OK */
} else if (pdu->version != session->version) {
/* ENHANCE: we should support multi-lingual sessions */
session->s_snmp_errno = SNMPERR_BAD_VERSION;
free(pktbuf);
return 0;
}
/* Build the message to send. */
if (isp->hook_realloc_build) {
result = isp->hook_realloc_build(session, pdu,
&pktbuf, &pktbuf_len, &offset);
packet = pktbuf;
length = offset;
} else if (isp->hook_build) {
packet = pktbuf;
length = pktbuf_len;
result = isp->hook_build(session, pdu, pktbuf, &length);
} else {
#ifdef USE_REVERSE_ASNENCODING
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_REVERSE_ENCODE)) {
result = snmp_build(&pktbuf, &pktbuf_len, &offset, session, pdu);
packet = pktbuf + pktbuf_len - offset;
length = offset;
} else {
#endif
packet = pktbuf;
length = pktbuf_len;
result = snmp_build(&pktbuf, &length, &offset, session, pdu);
#ifdef USE_REVERSE_ASNENCODING
}
#endif
}
if (result < 0) {
DEBUGMSGTL(("sess_async_send", "encoding failure\n"));
free(pktbuf);
return 0;
}
/* Make sure we don't send something that is bigger than the msgMaxSize
specified in the received PDU. */
if (session->sndMsgMaxSize != 0 && length > session->sndMsgMaxSize) {
DEBUGMSGTL(("sess_async_send",
"length of packet (%lu) exceeds session maximum (%lu)\n",
length, session->sndMsgMaxSize));
session->s_snmp_errno = SNMPERR_TOO_LONG;
free(pktbuf);
return 0;
}
/* Check that the underlying transport is capable of sending a packet as
large as length. */
if (transport->msgMaxSize != 0 && length > transport->msgMaxSize) {
DEBUGMSGTL(("sess_async_send",
"length of packet (%lu) exceeds transport maximum (%lu)\n",
length, transport->msgMaxSize));
session->s_snmp_errno = SNMPERR_TOO_LONG;
free(pktbuf);
return 0;
}
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_DUMP_PACKET)) {
if (transport->f_fmtaddr != NULL) {
char *dest_txt = transport->f_fmtaddr(transport, pdu->transport_data,
pdu->transport_data_length);
if (dest_txt != NULL) {
snmp_log(LOG_DEBUG, "\nSending %u bytes to %s\n", length, dest_txt);
free(dest_txt);
} else {
snmp_log(LOG_DEBUG, "\nSending %u bytes to <UNKNOWN>\n", length);
}
}
xdump(packet, length, "");
}
/* Send the message. */
result = transport->f_send(transport, packet, length,
&(pdu->transport_data),
&(pdu->transport_data_length));
free(pktbuf);
if (result < 0) {
session->s_snmp_errno = SNMPERR_BAD_SENDTO;
session->s_errno = errno;
return 0;
}
reqid = pdu->reqid;
/* Add to pending requests list if we expect a response. */
if (pdu->flags & UCD_MSG_FLAG_EXPECT_RESPONSE) {
struct request_list *rp;
struct timeval tv;
rp = (struct request_list *)calloc( 1, sizeof(struct request_list));
if (rp == NULL) {
session->s_snmp_errno = SNMPERR_GENERR;
return 0;
}
gettimeofday(&tv, (struct timezone *)0);
rp->pdu = pdu;
rp->request_id = pdu->reqid;
rp->message_id = pdu->msgid;
rp->callback = callback;
rp->cb_data = cb_data;
rp->retries = 0;
if (pdu->flags & UCD_MSG_FLAG_PDU_TIMEOUT) {
rp->timeout = pdu->time * 1000000L;
} else {
rp->timeout = session->timeout;
}
rp->time = tv;
tv.tv_usec += rp->timeout;
tv.tv_sec += tv.tv_usec / 1000000L;
tv.tv_usec %= 1000000L;
rp->expire = tv;
/* XX lock should be per session ! */
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
if (isp->requestsEnd) {
rp->next_request = isp->requestsEnd->next_request;
isp->requestsEnd->next_request = rp;
isp->requestsEnd = rp;
} else {
rp->next_request = isp->requests;
isp->requests = rp;
isp->requestsEnd = rp;
}
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
} else {
/* No response expected... */
if (reqid) {
/* Free v1 or v2 TRAP PDU iff no error */
snmp_free_pdu(pdu);
}
}
return reqid;
}
int
snmp_sess_async_send(void *sessp,
struct snmp_pdu *pdu,
snmp_callback callback,
void *cb_data)
{
int rc;
if (sessp == NULL) {
snmp_errno = SNMPERR_BAD_SESSION; /*MTCRITICAL_RESOURCE*/
return(0);
}
rc = _sess_async_send(sessp, pdu, callback, cb_data);
if (rc == 0) {
struct session_list *psl;
struct snmp_session *pss;
psl = (struct session_list *)sessp;
pss = psl->session;
SET_SNMP_ERROR(pss->s_snmp_errno);
}
return rc;
}
/*
* Frees the variable and any malloc'd data associated with it.
*/
void
snmp_free_var(struct variable_list *var)
{
if (!var) return;
if (var->name != var->name_loc)
SNMP_FREE(var->name);
if (var->val.string != var->buf)
SNMP_FREE(var->val.string);
if (var->data) {
if (var->dataFreeHook) {
var->dataFreeHook(var->data);
var->data = NULL;
} else {
SNMP_FREE(var->data);
}
}
free((char *)var);
}
void snmp_free_varbind(struct variable_list *var)
{
struct variable_list *ptr;
while(var) {
ptr = var->next_variable;
snmp_free_var(var);
var = ptr;
}
}
/*
* Frees the pdu and any malloc'd data associated with it.
*/
void
snmp_free_pdu(struct snmp_pdu *pdu)
{
struct snmp_secmod_def *sptr;
if (!pdu) return;
if ((sptr = find_sec_mod(pdu->securityModel)) != NULL &&
sptr->pdu_free != NULL) {
(*sptr->pdu_free)(pdu);
}
snmp_free_varbind(pdu->variables);
SNMP_FREE(pdu->enterprise);
SNMP_FREE(pdu->community);
SNMP_FREE(pdu->contextEngineID);
SNMP_FREE(pdu->securityEngineID);
SNMP_FREE(pdu->contextName);
SNMP_FREE(pdu->securityName);
SNMP_FREE(pdu->transport_data);
free((char *)pdu);
}
/* This function processes a complete (according to asn_check_packet or the
AgentX equivalent) packet, parsing it into a PDU and calling the relevant
callbacks. On entry, packetptr points at the packet in the session's
buffer and length is the length of the packet. */
static int
_sess_process_packet(void *sessp, struct snmp_session *sp,
struct snmp_internal_session *isp,
snmp_transport *transport,
void *opaque, int olength,
u_char *packetptr, int length)
{
struct session_list *slp = (struct session_list *)sessp;
struct snmp_pdu *pdu;
struct request_list *rp, *orp = NULL;
struct snmp_secmod_def *sptr;
int ret = 0;
DEBUGMSGTL(("sess_process_packet", "session %p, pkt %p length %d\n",
sessp, packetptr, length));
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_DUMP_PACKET)) {
if (transport->f_fmtaddr != NULL) {
char *addrtxt = transport->f_fmtaddr(transport, opaque, olength);
if (addrtxt != NULL) {
snmp_log(LOG_DEBUG, "\nReceived %d bytes from %s\n", length, addrtxt);
free(addrtxt);
} else {
snmp_log(LOG_DEBUG, "\nReceived %d bytes from <UNKNOWN>\n", length);
}
}
xdump(packetptr, length, "");
}
/* Do transport-level filtering (e.g. IP-address based allow/deny). */
if (isp->hook_pre) {
if (isp->hook_pre(sp, transport, opaque, olength) == 0) {
DEBUGMSGTL(("sess_process_packet", "pre-parse fail\n"));
return -1;
}
}
pdu = (struct snmp_pdu *)calloc(1,sizeof(struct snmp_pdu));
if (pdu == NULL) {
DEBUGMSGTL(("sess_process_packet", "can't malloc space for PDU\n"));
return -1;
}
/* Save the transport-level data specific to this reception (e.g. UDP
source address). */
pdu->transport_data = opaque;
pdu->transport_data_length = olength;
pdu->tDomain = transport->domain;
pdu->tDomainLen = transport->domain_length;
if (isp->hook_parse) {
ret = isp->hook_parse(sp, pdu, packetptr, length);
} else {
ret = snmp_parse(sessp, sp, pdu, packetptr, length);
}
if (ret != SNMP_ERR_NOERROR) {
DEBUGMSGTL(("sess_process_packet", "parse fail\n"));
}
if (isp->hook_post) {
if (isp->hook_post(sp, pdu, ret) == 0) {
DEBUGMSGTL(("sess_process_packet", "post-parse fail\n"));
snmp_free_pdu(pdu);
return -1;
}
}
if (ret != SNMP_ERR_NOERROR) {
snmp_free_pdu(pdu);
return -1;
}
if (pdu->flags & UCD_MSG_FLAG_RESPONSE_PDU) {
/* Call USM to free any securityStateRef supplied with the message. */
if (pdu->securityStateRef) {
sptr = find_sec_mod(pdu->securityModel);
if (sptr) {
if (sptr->pdu_free_state_ref) {
(*sptr->pdu_free_state_ref)(pdu->securityStateRef);
} else {
snmp_log(LOG_ERR, "Security Model %d can't free state references\n",
pdu->securityModel);
}
} else {
snmp_log(LOG_ERR, "Can't find security model to free ptr: %d\n",
pdu->securityModel);
}
pdu->securityStateRef = NULL;
}
for (rp = isp->requests; rp; orp = rp, rp = rp->next_request) {
snmp_callback callback;
void *magic;
if (pdu->version == SNMP_VERSION_3) {
/* msgId must match for v3 messages. */
if (rp->message_id != pdu->msgid) {
continue;
}
/* Check that message fields match original, if not, no further
processing. */
if (!snmpv3_verify_msg(rp,pdu)) {
break;
}
} else {
if (rp->request_id != pdu->reqid) {
continue;
}
}
if (rp->callback) {
callback = rp->callback;
magic = rp->cb_data;
} else {
callback = sp->callback;
magic = sp->callback_magic;
}
/* MTR snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION); ?* XX lock
should be per session ! */
if (callback == NULL || callback(SNMP_CALLBACK_OP_RECEIVED_MESSAGE,
sp, pdu->reqid, pdu, magic) == 1) {
if (pdu->command == SNMP_MSG_REPORT) {
if (sp->s_snmp_errno == SNMPERR_NOT_IN_TIME_WINDOW) {
/* trigger immediate retry on recoverable Reports
* (notInTimeWindow), incr_retries == TRUE to prevent
* inifinite resend */
if (rp->retries <= sp->retries) {
snmp_resend_request(slp, rp, TRUE);
break;
}
} else {
if (SNMPV3_IGNORE_UNAUTH_REPORTS) {
break;
}
}
/* Handle engineID discovery. */
if (!sp->securityEngineIDLen && pdu->securityEngineIDLen) {
sp->securityEngineID = (u_char *)malloc(pdu->securityEngineIDLen);
if (sp->securityEngineID == NULL) {
/* TODO FIX: recover after message callback *?
return -1;
*/
}
memcpy(sp->securityEngineID, pdu->securityEngineID,
pdu->securityEngineIDLen);
sp->securityEngineIDLen = pdu->securityEngineIDLen;
if (!sp->contextEngineIDLen) {
sp->contextEngineID = (u_char *)malloc(pdu->securityEngineIDLen);
if (sp->contextEngineID == NULL) {
/* TODO FIX: recover after message callback *?
return -1;
*/
}
memcpy(sp->contextEngineID, pdu->securityEngineID,
pdu->securityEngineIDLen);
sp->contextEngineIDLen = pdu->securityEngineIDLen;
}
}
}
/* Successful, so delete request. */
if (isp->requests == rp) {
isp->requests = rp->next_request;
if (isp->requestsEnd == rp) {
isp->requestsEnd = NULL;
}
} else {
orp->next_request = rp->next_request;
if (isp->requestsEnd == rp) {
isp->requestsEnd = orp;
}
}
snmp_free_pdu(rp->pdu);
free((char *)rp);
/* There shouldn't be any more requests with the same reqid. */
break;
}
/* MTR snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION); ?* XX lock should be per session ! */
}
} else {
if (sp->callback) {
/* MTR snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION); */
sp->callback(SNMP_CALLBACK_OP_RECEIVED_MESSAGE,
sp, pdu->reqid, pdu,sp->callback_magic);
/* MTR snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION); */
}
}
/* Call USM to free any securityStateRef supplied with the message. */
if (pdu != NULL && pdu->securityStateRef && pdu->command == SNMP_MSG_TRAP2) {
sptr = find_sec_mod(pdu->securityModel);
if (sptr) {
if (sptr->pdu_free_state_ref) {
(*sptr->pdu_free_state_ref)(pdu->securityStateRef);
} else {
snmp_log(LOG_ERR, "Security Model %d can't free state references\n",
pdu->securityModel);
}
} else {
snmp_log(LOG_ERR, "Can't find security model to free ptr: %d\n",
pdu->securityModel);
}
pdu->securityStateRef = NULL;
}
snmp_free_pdu(pdu);
return 0;
}
/*
* Checks to see if any of the fd's set in the fdset belong to
* snmp. Each socket with it's fd set has a packet read from it
* and snmp_parse is called on the packet received. The resulting pdu
* is passed to the callback routine for that session. If the callback
* routine returns successfully, the pdu and it's request are deleted.
*/
void
snmp_read(fd_set *fdset)
{
struct session_list *slp;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
for(slp = Sessions; slp; slp = slp->next){
snmp_sess_read((void *)slp, fdset);
}
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
}
/* Same as snmp_read, but works just one session. */
/* returns 0 if success, -1 if fail */
/* MTR: can't lock here and at snmp_read */
/* Beware recursive send maybe inside snmp_read callback function. */
int
_sess_read(void *sessp, fd_set *fdset)
{
struct session_list *slp = (struct session_list *)sessp;
struct snmp_session *sp = slp?slp->session:NULL;
struct snmp_internal_session *isp = slp?slp->internal:NULL;
snmp_transport *transport = slp?slp->transport:NULL;
size_t length = 0, pdulen = 0, rxbuf_len = 65536;
u_char *rxbuf = NULL;
int olength = 0, rc = 0;
void *opaque = NULL;
if (!sp || !isp || !transport) {
DEBUGMSGTL(("sess_read", "read fail: closing...\n"));
return 0;
}
if (!fdset || !(FD_ISSET(transport->sock, fdset))) {
DEBUGMSGTL(("sess_read", "not reading %d (fdset %p set %d)\n",
transport->sock, fdset,
fdset?FD_ISSET(transport->sock, fdset):-9));
return 0;
}
sp->s_snmp_errno = 0;
sp->s_errno = 0;
if (transport->flags & SNMP_TRANSPORT_FLAG_LISTEN) {
int data_sock = transport->f_accept(transport);
if (data_sock >= 0) {
/* We've successfully accepted a new stream-based connection. It's not
too clear what should happen here if we are using the single-session
API at this point. Basically a "session accepted" callback is
probably needed to hand the new session over to the application.
However, for now, as in the original snmp_api, we will ASSUME that
we're using the traditional API, and simply add the new session to
the list. Note we don't have to get the Session list lock here,
because under that assumption we already hold it (this is also why
we don't just use snmp_add).
The moral of the story is: don't use listening stream-based
transports in a multi-threaded environment because something will go
HORRIBLY wrong (and also that SNMP/TCP is not trivial).
Another open issue: what should happen to sockets that have been
accept()ed from a listening socket when that original socket is
closed? If they are left open, then attempting to re-open the
listening socket will fail, which is semantically confusing.
Perhaps there should be some kind of chaining in the transport
structure so that they can all be closed. Discuss. ;-) */
snmp_transport *new_transport = snmp_transport_copy(transport);
if (new_transport != NULL) {
struct session_list *nslp = NULL;
new_transport->sock = data_sock;
new_transport->flags &= ~SNMP_TRANSPORT_FLAG_LISTEN;
nslp = (struct session_list *)snmp_sess_add_ex(sp, new_transport,
isp->hook_pre, isp->hook_parse,
isp->hook_post, isp->hook_build,
isp->hook_realloc_build, isp->check_packet);
if (nslp != NULL) {
nslp->next = Sessions;
Sessions = nslp;
} else {
new_transport->f_close(new_transport);
snmp_transport_free(new_transport);
}
return 0;
} else {
sp->s_snmp_errno = SNMPERR_MALLOC;
sp->s_errno = errno;
snmp_set_detail(strerror(errno));
return -1;
}
} else {
sp->s_snmp_errno = SNMPERR_BAD_RECVFROM;
sp->s_errno = errno;
snmp_set_detail(strerror(errno));
return -1;
}
}
/* Work out where to receive the data to. */
if (transport->flags & SNMP_TRANSPORT_FLAG_STREAM) {
if (isp->packet == NULL) {
/* We have no saved packet. Allocate one. */
if ((isp->packet = (u_char *)malloc(rxbuf_len)) == NULL) {
DEBUGMSGTL(("sess_read",
"can't malloc %d bytes for rxbuf\n",rxbuf_len));
return 0;
} else {
rxbuf = isp->packet;
isp->packet_size = rxbuf_len;
isp->packet_len = 0;
}
} else {
/* We have saved a partial packet from last time. Extend that, if
necessary, and receive new data after the old data. */
u_char *newbuf;
if (isp->packet_size < isp->packet_len + rxbuf_len) {
newbuf = (u_char *)realloc(isp->packet, isp->packet_len + rxbuf_len);
if (newbuf == NULL) {
DEBUGMSGTL(("sess_read","can't malloc %d more for rxbuf (%d tot)\n",
rxbuf_len, isp->packet_len + rxbuf_len));
return 0;
} else {
isp->packet = newbuf;
isp->packet_size = isp->packet_len + rxbuf_len;
rxbuf = isp->packet + isp->packet_len;
}
} else {
rxbuf = isp->packet + isp->packet_len;
rxbuf_len = isp->packet_size - isp->packet_len;
}
}
} else {
if ((rxbuf = (u_char *)malloc(rxbuf_len)) == NULL) {
DEBUGMSGTL(("sess_read", "can't malloc %d bytes for rxbuf\n",rxbuf_len));
return 0;
}
}
length = transport->f_recv(transport, rxbuf, rxbuf_len, &opaque, &olength);
if (length == -1 && !(transport->flags & SNMP_TRANSPORT_FLAG_STREAM)) {
sp->s_snmp_errno = SNMPERR_BAD_RECVFROM;
sp->s_errno = errno;
snmp_set_detail(strerror(errno));
free(rxbuf);
if (opaque != NULL) {
free(opaque);
}
return -1;
}
/* Remote end closed connection. */
if (length <= 0 && transport->flags & SNMP_TRANSPORT_FLAG_STREAM) {
/* Alert the application if possible. */
if (sp->callback != NULL) {
DEBUGMSGTL(("sess_read", "perform callback with op=DISCONNECT\n"));
(void)sp->callback(SNMP_CALLBACK_OP_DISCONNECT,
sp, 0, NULL, sp->callback_magic);
}
/* Close socket and mark session for deletion. */
DEBUGMSGTL(("sess_read", "fd %d closed\n", transport->sock));
transport->f_close(transport);
free(rxbuf);
isp->packet = NULL;
if (opaque != NULL) {
free(opaque);
}
return -1;
}
if (transport->flags & SNMP_TRANSPORT_FLAG_STREAM) {
u_char *pptr = isp->packet;
isp->packet_len += length;
while (isp->packet_len > 0) {
/* Get the total data length we're expecting (and need to wait for). */
if (isp->check_packet) {
pdulen = isp->check_packet(pptr, isp->packet_len);
} else {
pdulen = asn_check_packet(pptr, isp->packet_len);
}
DEBUGMSGTL(("sess_read", " loop packet_len %d, PDU length %d\n",
isp->packet_len, pdulen));
if (pdulen > MAX_PACKET_LENGTH) {
/* Illegal length, drop the connection. */
snmp_log(LOG_ERR, "Maximum packet size exceeded in a request.\n");
transport->f_close(transport);
if (opaque != NULL) {
free(opaque);
}
return -1;
}
if (pdulen > isp->packet_len) {
/* We don't have a complete packet yet. Return, and wait for more
data to arrive. */
DEBUGMSGTL(("sess_read", "pkt not complete (need %d got %d so far)\n",
pdulen, isp->packet_len));
if (opaque != NULL) {
free(opaque);
}
return 0;
}
/* We have *at least* one complete packet in the buffer now. */
if ((rc = _sess_process_packet(sessp, sp, isp, transport,
opaque, olength, pptr, pdulen))) {
/* Something went wrong while processing this packet -- set the
errno. */
if (sp->s_snmp_errno != 0) {
SET_SNMP_ERROR(sp->s_snmp_errno);
}
}
pptr += pdulen;
isp->packet_len -= pdulen;
}
if (isp->packet_len < 0) {
/* Obviously this should never happen! */
snmp_log(LOG_ERR, "-ve packet_len %d, dropping connection %d\n",
isp->packet_len, transport->sock);
transport->f_close(transport);
return -1;
} else if (isp->packet_len == 0) {
/* This is good: it means the packet buffer contained an integral
number of PDUs, so we don't have to save any data for next time. We
can free() the buffer now to keep the memory footprint down. */
free(isp->packet);
isp->packet = NULL;
isp->packet_size = 0;
isp->packet_len = 0;
return rc;
}
/* If we get here, then there is a partial packet of length
isp->packet_len bytes starting at pptr left over. Move that to the
start of the buffer, and then realloc() the buffer down to size to
reduce the memory footprint. */
memmove(isp->packet, pptr, isp->packet_len);
DEBUGMSGTL(("sess_read", "end: memmove(%p, %p, %d); realloc(%p, %d)\n",
isp->packet, pptr, isp->packet_len,
isp->packet, isp->packet_len));
if ((rxbuf = realloc(isp->packet, isp->packet_len)) == NULL) {
/* I don't see why this should ever fail, but it's not a big deal. */
DEBUGMSGTL(("sess_read", "realloc() failed\n"));
} else {
DEBUGMSGTL(("sess_read", "realloc() okay, old buffer %p, new %p\n",
isp->packet, rxbuf));
isp->packet = rxbuf;
isp->packet_size = isp->packet_len;
}
return rc;
} else {
rc = _sess_process_packet(sessp, sp, isp, transport, opaque, olength,
rxbuf, length);
free(rxbuf);
return rc;
}
}
/* returns 0 if success, -1 if fail */
int
snmp_sess_read(void *sessp, fd_set *fdset)
{
struct session_list *psl;
struct snmp_session *pss;
int rc;
rc = _sess_read(sessp, fdset);
psl = (struct session_list *)sessp;
pss = psl->session;
if (rc && pss->s_snmp_errno) {
SET_SNMP_ERROR(pss->s_snmp_errno);
}
return rc;
}
/*
* Returns info about what snmp requires from a select statement.
* numfds is the number of fds in the list that are significant.
* All file descriptors opened for SNMP are OR'd into the fdset.
* If activity occurs on any of these file descriptors, snmp_read
* should be called with that file descriptor set
*
* The timeout is the latest time that SNMP can wait for a timeout. The
* select should be done with the minimum time between timeout and any other
* timeouts necessary. This should be checked upon each invocation of select.
* If a timeout is received, snmp_timeout should be called to check if the
* timeout was for SNMP. (snmp_timeout is idempotent)
*
* The value of block indicates how the timeout value is interpreted.
* If block is true on input, the timeout value will be treated as undefined,
* but it must be available for setting in snmp_select_info. On return,
* block is set to true if the value returned for timeout is undefined;
* when block is set to false, timeout may be used as a parmeter to 'select'.
*
* snmp_select_info returns the number of open sockets. (i.e. The number of
* sessions open)
*/
int
snmp_select_info(int *numfds,
fd_set *fdset,
struct timeval *timeout,
int *block)
/* input: set to 1 if input timeout value is undefined */
/* set to 0 if input timeout value is defined */
/* output: set to 1 if output timeout value is undefined */
/* set to 0 if output rimeout vlaue id defined */
{
return snmp_sess_select_info((void *)0, numfds, fdset, timeout, block);
}
/* Same as snmp_select_info, but works just one session. */
int
snmp_sess_select_info(void *sessp,
int *numfds,
fd_set *fdset,
struct timeval *timeout,
int *block)
{
struct session_list *slptest = (struct session_list *)sessp;
struct session_list *slp, *next=NULL;
struct request_list *rp;
struct timeval now, earliest, delta;
int timer_set = 0;
int active = 0, requests = 0;
int next_alarm = 0;
timerclear(&earliest);
/*
* For each request outstanding, add its socket to the fdset,
* and if it is the earliest timeout to expire, mark it as lowest.
* If a single session is specified, do just for that session.
*/
if (sessp) {
slp = slptest;
} else {
slp = Sessions;
}
DEBUGMSGTL(("sess_select", "for %s session%s: ",
sessp?"single":"all", sessp?"":"s"));
for(; slp; slp = next) {
next = slp->next;
if (slp->transport == NULL) {
/* Close in progress -- skip this one. */
DEBUGMSG(("sess_select", "skip "));
continue;
}
if (slp->transport->sock == -1) {
/* This session was marked for deletion. */
DEBUGMSG(("sess_select", "delete\n"));
if (sessp == NULL) {
snmp_close(slp->session);
} else {
snmp_sess_close(slp);
}
DEBUGMSGTL(("sess_select", "for %s session%s: ",
sessp?"single":"all", sessp?"":"s"));
continue;
}
DEBUGMSG(("sess_select", "%d ", slp->transport->sock));
if ((slp->transport->sock + 1) > *numfds) {
*numfds = (slp->transport->sock + 1);
}
FD_SET(slp->transport->sock, fdset);
if (slp->internal != NULL && slp->internal->requests) {
/* Found another session with outstanding requests. */
requests++;
for(rp = slp->internal->requests; rp; rp = rp->next_request) {
if ((!timerisset(&earliest)
|| (timercmp(&rp->expire, &earliest, <)))) {
earliest = rp->expire;
}
}
}
active++;
if (sessp) {
/* Single session processing. */
break;
}
}
DEBUGMSG(("sess_select", "\n"));
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_ALARM_DONT_USE_SIG)) {
next_alarm = get_next_alarm_delay_time(&delta);
}
if (next_alarm == 0 && requests == 0) {
/* If none are active, skip arithmetic. */
*block = 1; /* can block - timeout value is undefined if no requests*/
return active;
}
/*
* Now find out how much time until the earliest timeout. This
* transforms earliest from an absolute time into a delta time, the
* time left until the select should timeout.
*/
gettimeofday(&now,(struct timezone *)0);
/*Now = now;*/
if (next_alarm) {
delta.tv_sec += now.tv_sec;
delta.tv_usec += now.tv_usec;
while (delta.tv_usec >= 1000000) {
delta.tv_usec -= 1000000;
delta.tv_sec += 1;
}
if (!timerisset(&earliest) ||
((earliest.tv_sec > delta.tv_sec) ||
((earliest.tv_sec == delta.tv_sec) &&
(earliest.tv_usec > delta.tv_usec)))) {
earliest.tv_sec = delta.tv_sec;
earliest.tv_usec = delta.tv_usec;
}
}
if (timer_set || earliest.tv_sec < now.tv_sec) {
earliest.tv_sec = 0;
earliest.tv_usec = 0;
}
else if (earliest.tv_sec == now.tv_sec) {
earliest.tv_sec = 0;
earliest.tv_usec = (earliest.tv_usec - now.tv_usec);
if (earliest.tv_usec < 0) {
earliest.tv_usec = 100;
}
}
else {
earliest.tv_sec = (earliest.tv_sec - now.tv_sec);
earliest.tv_usec = (earliest.tv_usec - now.tv_usec);
if (earliest.tv_usec < 0) {
earliest.tv_sec --;
earliest.tv_usec = (1000000L + earliest.tv_usec);
}
}
/* if it was blocking before or our delta time is less, reset timeout */
if ((*block || (timercmp(&earliest, timeout, <)))) {
*timeout = earliest;
*block = 0;
}
return active;
}
/*
* snmp_timeout should be called whenever the timeout from snmp_select_info
* expires, but it is idempotent, so snmp_timeout can be polled (probably a
* cpu expensive proposition). snmp_timeout checks to see if any of the
* sessions have an outstanding request that has timed out. If it finds one
* (or more), and that pdu has more retries available, a new packet is formed
* from the pdu and is resent. If there are no more retries available, the
* callback for the session is used to alert the user of the timeout.
*/
void
snmp_timeout (void)
{
struct session_list *slp;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
for(slp = Sessions; slp; slp = slp->next) {
snmp_sess_timeout((void *)slp);
}
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
}
static int
snmp_resend_request(struct session_list *slp, struct request_list *rp,
int incr_retries)
{
struct snmp_internal_session *isp;
struct snmp_session *sp;
snmp_transport *transport;
u_char *pktbuf = NULL, *packet = NULL;
size_t pktbuf_len = 0, offset = 0, length = 0;
struct timeval tv, now;
int result = 0;
sp = slp->session; isp = slp->internal; transport = slp->transport;
if (!sp || !isp || !transport) {
DEBUGMSGTL(("sess_read", "resend fail: closing...\n"));
return 0;
}
if ((pktbuf = malloc(2048)) == NULL) {
DEBUGMSGTL(("sess_resend", "couldn't malloc initial packet buffer\n"));
return 0;
} else {
pktbuf_len = 2048;
}
if (incr_retries) {
rp->retries++;
}
/* Always increment msgId for resent messages. */
rp->pdu->msgid = rp->message_id = snmp_get_next_msgid();
if (isp->hook_realloc_build) {
result = isp->hook_realloc_build(sp, rp->pdu,
&pktbuf, &pktbuf_len, &offset);
packet = pktbuf;
length = offset;
} else if (isp->hook_build) {
packet = pktbuf;
length = pktbuf_len;
result = isp->hook_build(sp, rp->pdu, pktbuf, &length);
} else {
#ifdef USE_REVERSE_ASNENCODING
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_REVERSE_ENCODE)) {
result = snmp_build(&pktbuf, &pktbuf_len, &offset, sp, rp->pdu);
packet = pktbuf + pktbuf_len - offset;
length = offset;
} else {
#endif
packet = pktbuf;
length = pktbuf_len;
result = snmp_build(&pktbuf, &length, &offset, sp, rp->pdu);
#ifdef USE_REVERSE_ASNENCODING
}
#endif
}
if (result < 0) {
/* This should never happen. */
DEBUGMSGTL(("sess_resend", "encoding failure\n"));
if (pktbuf != NULL) {
free(pktbuf);
}
return -1;
}
if (ds_get_boolean(DS_LIBRARY_ID, DS_LIB_DUMP_PACKET)) {
if (transport->f_fmtaddr != NULL) {
char *string = NULL;
string = transport->f_fmtaddr(NULL, rp->pdu->transport_data,
rp->pdu->transport_data_length);
if (string != NULL) {
snmp_log(LOG_DEBUG, "\nResending %d bytes to %s\n", length, string);
free(string);
} else {
snmp_log(LOG_DEBUG, "\nResending %d bytes to <UNKNOWN>\n", length);
}
}
xdump(packet, length, "");
}
result = transport->f_send(transport, packet, length,
&(rp->pdu->transport_data),
&(rp->pdu->transport_data_length));
/* We are finished with the local packet buffer, if we allocated one (due
to there being no saved packet). */
if (pktbuf != NULL) {
free(pktbuf);
pktbuf = packet = NULL;
}
if (result < 0) {
sp->s_snmp_errno = SNMPERR_BAD_SENDTO;
sp->s_errno = errno;
snmp_set_detail(strerror(errno));
return -1;
} else {
gettimeofday(&now, (struct timezone *)0);
tv = now;
rp->time = tv;
tv.tv_usec += rp->timeout;
tv.tv_sec += tv.tv_usec / 1000000L;
tv.tv_usec %= 1000000L;
rp->expire = tv;
}
return 0;
}
void
snmp_sess_timeout(void *sessp)
{
struct session_list *slp = (struct session_list*)sessp;
struct snmp_session *sp;
struct snmp_internal_session *isp;
struct request_list *rp, *orp = NULL, *freeme = NULL;
struct timeval now;
snmp_callback callback;
void *magic;
struct snmp_secmod_def *sptr;
sp = slp->session; isp = slp->internal;
if (!sp || !isp) {
DEBUGMSGTL(("sess_read","timeout fail: closing...\n"));
return;
}
gettimeofday(&now,(struct timezone *)0);
/*
* For each request outstanding, check to see if it has expired.
*/
for(rp = isp->requests; rp; rp = rp->next_request) {
if (freeme != NULL) {
/* frees rp's after the for loop goes on to the next_request */
free((char *)freeme);
freeme = NULL;
}
if ((timercmp(&rp->expire, &now, <))) {
if ((sptr = find_sec_mod(rp->pdu->securityModel)) != NULL &&
sptr->pdu_timeout != NULL) {
/* call security model if it needs to know about this */
(*sptr->pdu_timeout)(rp->pdu);
}
/* this timer has expired */
if (rp->retries >= sp->retries) {
if (rp->callback) {
callback = rp->callback;
magic = rp->cb_data;
} else {
callback = sp->callback;
magic = sp->callback_magic;
}
/* No more chances, delete this entry */
if (callback) {
callback(SNMP_CALLBACK_OP_TIMED_OUT, sp,
rp->pdu->reqid, rp->pdu, magic);
}
if (isp->requests == rp) {
isp->requests = rp->next_request;
if (isp->requestsEnd == rp) {
isp->requestsEnd = NULL;
}
} else {
orp->next_request = rp->next_request;
if (isp->requestsEnd == rp) {
isp->requestsEnd = orp;
}
}
snmp_free_pdu(rp->pdu); /* FIX rp is already free'd! */
freeme = rp;
continue; /* don't update orp below */
} else {
if (snmp_resend_request(slp, rp, TRUE)) {
break;
}
}
}
orp = rp;
}
if (freeme != NULL) {
free((char *)freeme);
freeme = NULL;
}
}
/* lexicographical compare two object identifiers.
* Returns -1 if name1 < name2,
* 0 if name1 = name2,
* 1 if name1 > name2
*
* Caution: this method is called often by
* command responder applications (ie, agent).
*/
int
snmp_oid_compare(const oid *in_name1,
size_t len1,
const oid *in_name2,
size_t len2)
{
register int len;
register const oid * name1 = in_name1;
register const oid * name2 = in_name2;
/* len = minimum of len1 and len2 */
if (len1 < len2)
len = len1;
else
len = len2;
/* find first non-matching OID */
while(len-- > 0) {
/* these must be done in seperate comparisons, since
subtracting them and using that result has problems with
subids > 2^31. */
if (*(name1) < *(name2))
return -1;
if (*(name1++) > *(name2++))
return 1;
}
/* both OIDs equal up to length of shorter OID */
if (len1 < len2)
return -1;
if (len2 < len1)
return 1;
return 0;
}
/*
* Add a variable with the requested name to the end of the list of
* variables for this pdu.
*/
struct variable_list *
snmp_pdu_add_variable(struct snmp_pdu *pdu,
oid *name,
size_t name_length,
u_char type,
u_char *value,
size_t len)
{
return snmp_varlist_add_variable(&pdu->variables, name, name_length, type,
value, len);
}
/*
* Add a variable with the requested name to the end of the list of
* variables for this pdu.
*/
struct variable_list *
snmp_varlist_add_variable(struct variable_list **varlist,
oid *name,
size_t name_length,
u_char type,
u_char *value,
size_t len)
{
struct variable_list *vars, *vtmp;
int largeval = 1;
if (varlist == NULL)
return NULL;
vars = (struct variable_list *)malloc(sizeof(struct variable_list));
if (vars == NULL)
return NULL;
vars->next_variable = 0; vars->name = 0; vars->val.string = 0;
vars->data = 0; vars->dataFreeHook = 0; vars->index = 0;
/* use built-in storage for smaller values */
if (len <= (sizeof(vars->buf) - 1)) {
vars->val.string = (u_char *)vars->buf;
largeval = 0;
}
vars->type = type;
vars->val_len = len;
switch(type){
case ASN_INTEGER:
case ASN_UNSIGNED:
case ASN_TIMETICKS:
case ASN_IPADDRESS:
case ASN_COUNTER:
memmove(vars->val.integer, value, vars->val_len);
vars->val_len = sizeof(long);
break;
case ASN_OBJECT_ID:
case ASN_PRIV_IMPLIED_OBJECT_ID:
case ASN_PRIV_INCL_RANGE:
case ASN_PRIV_EXCL_RANGE:
if (largeval) {
vars->val.objid = (oid *)malloc(vars->val_len);
}
if (vars->val.objid == NULL) {
return NULL;
}
memmove(vars->val.objid, value, vars->val_len);
break;
case ASN_PRIV_IMPLIED_OCTET_STR:
case ASN_OCTET_STR:
case ASN_BIT_STR:
case ASN_OPAQUE:
case ASN_NSAP:
if (largeval) {
vars->val.string = (u_char *)malloc(vars->val_len + 1);
}
if (vars->val.string == NULL) {
return NULL;
}
memmove(vars->val.string, value, vars->val_len);
/* Make sure the string is zero-terminated; some bits of code make
this assumption. Easier to do this here than fix all these wrong
assumptions. */
vars->val.string[vars->val_len] = '\0';
break;
case SNMP_NOSUCHOBJECT:
case SNMP_NOSUCHINSTANCE:
case SNMP_ENDOFMIBVIEW:
case ASN_NULL:
vars->val_len = 0;
vars->val.string = NULL;
break;
#ifdef OPAQUE_SPECIAL_TYPES
case ASN_OPAQUE_U64:
case ASN_OPAQUE_I64:
#endif /* OPAQUE_SPECIAL_TYPES */
case ASN_COUNTER64:
vars->val_len = sizeof(struct counter64);
memmove(vars->val.counter64, value, vars->val_len);
break;
#ifdef OPAQUE_SPECIAL_TYPES
case ASN_OPAQUE_FLOAT:
vars->val_len = sizeof(float);
memmove(vars->val.floatVal, value, vars->val_len);
break;
case ASN_OPAQUE_DOUBLE:
vars->val_len = sizeof(double);
memmove(vars->val.doubleVal, value, vars->val_len);
break;
#endif /* OPAQUE_SPECIAL_TYPES */
default:
snmp_set_detail("Internal error in type switching\n");
snmp_free_var(vars);
return (0);
}
if (name != NULL && snmp_set_var_objid(vars, name, name_length)) {
snmp_free_var(vars);
return (0);
}
/* put only qualified variable onto varlist */
if (*varlist == NULL) {
*varlist = vars;
} else {
for(vtmp = *varlist; vtmp->next_variable; vtmp = vtmp->next_variable);
vtmp->next_variable = vars;
}
return vars;
}
/*
* Add a variable with the requested name to the end of the list of
* variables for this pdu.
* Returns:
* may set these error types :
* SNMPERR_RANGE - type, value, or length not found or out of range
* SNMPERR_VALUE - value is not correct
* SNMPERR_BAD_NAME - name is not found
*
* returns 0 if success, error if failure.
*/
int
snmp_add_var(struct snmp_pdu *pdu,
oid *name,
size_t name_length,
char type,
const char *value)
{
const char *cp;
char *ecp;
int result = SNMPERR_SUCCESS;
int check = !ds_get_boolean(DS_LIBRARY_ID, DS_LIB_DONT_CHECK_RANGE);
u_char *buf = NULL;
const char *buf_ptr = NULL;
size_t buf_len = 0, value_len = 0, tint;
long ltmp;
struct tree *tp;
struct enum_list *ep;
struct range_list *rp;
#ifdef OPAQUE_SPECIAL_TYPES
double dtmp;
float ftmp;
struct counter64 c64tmp;
#endif /* OPAQUE_SPECIAL_TYPES */
tp = get_tree(name, name_length, get_tree_head());
if (!tp || !tp->type || tp->type > TYPE_SIMPLE_LAST) {
check = 0;
}
if (tp && type == '=') {
/* generic assignment - let the tree node decide value format */
switch (tp->type) {
case TYPE_INTEGER:
case TYPE_INTEGER32:
type = 'i'; break;
case TYPE_GAUGE:
case TYPE_UNSIGNED32:
type = 'u'; break;
case TYPE_UINTEGER:
type = '3'; break;
case TYPE_COUNTER:
type = 'c'; break;
case TYPE_TIMETICKS:
type = 't'; break;
case TYPE_OCTETSTR:
type = 's'; break;
case TYPE_BITSTRING:
type = 'b'; break;
case TYPE_IPADDR:
type = 'a'; break;
case TYPE_OBJID:
type = 'o'; break;
}
}
switch(type) {
case 'i':
if (check && tp->type != TYPE_INTEGER && tp->type != TYPE_INTEGER32) {
value = "INTEGER";
result = SNMPERR_VALUE;
goto type_error;
}
if (!*value) goto fail;
ltmp = strtol(value, &ecp, 10);
if (*ecp) {
ep = tp ? tp->enums : NULL;
while (ep) {
if (strcmp(value, ep->label) == 0) {
ltmp = ep->value;
break;
}
ep = ep->next;
}
if (!ep) {
result = SNMPERR_BAD_NAME;
snmp_set_detail(value);
break;
}
}
if (check && tp->ranges) {
rp = tp->ranges;
while (rp) {
if (rp->low <= ltmp && ltmp <= rp->high) break;
rp = rp->next;
}
if (!rp) {
result = SNMPERR_RANGE;
snmp_set_detail(value);
break;
}
}
snmp_pdu_add_variable(pdu, name, name_length, ASN_INTEGER,
(u_char *) &ltmp, sizeof(ltmp));
break;
case 'u':
if (check && tp->type != TYPE_GAUGE && tp->type != TYPE_UNSIGNED32) {
value = "Unsigned32";
result = SNMPERR_VALUE;
goto type_error;
}
ltmp = strtoul(value, &ecp, 10);
if (*value && !*ecp)
snmp_pdu_add_variable(pdu, name, name_length, ASN_UNSIGNED,
(u_char *) &ltmp, sizeof(ltmp));
else goto fail;
break;
case '3':
if (check && tp->type != TYPE_UINTEGER) {
value = "UInteger32";
result = SNMPERR_VALUE;
goto type_error;
}
ltmp = strtoul(value, &ecp, 10);
if (*value && !*ecp)
snmp_pdu_add_variable(pdu, name, name_length, ASN_UINTEGER,
(u_char *) &ltmp, sizeof(ltmp));
else goto fail;
break;
case 'c':
if (check && tp->type != TYPE_COUNTER) {
value = "Counter32";
result = SNMPERR_VALUE;
goto type_error;
}
ltmp = strtoul(value, &ecp, 10);
if (*value && !*ecp)
snmp_pdu_add_variable(pdu, name, name_length, ASN_COUNTER,
(u_char *) &ltmp, sizeof(ltmp));
else goto fail;
break;
case 't':
if (check && tp->type != TYPE_TIMETICKS) {
value = "Timeticks";
result = SNMPERR_VALUE;
goto type_error;
}
ltmp = strtoul(value, &ecp, 10);
if (*value && !*ecp)
snmp_pdu_add_variable(pdu, name, name_length, ASN_TIMETICKS,
(u_char *) &ltmp, sizeof(long));
else goto fail;
break;
case 'a':
if (check && tp->type != TYPE_IPADDR) {
value = "IpAddress";
result = SNMPERR_VALUE;
goto type_error;
}
ltmp = inet_addr(value);
if (ltmp != (long)-1 || !strcmp(value,"255.255.255.255"))
snmp_pdu_add_variable(pdu, name, name_length, ASN_IPADDRESS,
(u_char *) &ltmp, sizeof(long));
else goto fail;
break;
case 'o':
if (check && tp->type != TYPE_OBJID) {
value = "OBJECT IDENTIFIER";
result = SNMPERR_VALUE;
goto type_error;
}
if ((buf = malloc(sizeof(oid) * MAX_OID_LEN)) == NULL) {
result = SNMPERR_MALLOC;
} else {
tint = MAX_OID_LEN;
if (snmp_parse_oid(value, (oid *)buf, &tint)) {
snmp_pdu_add_variable(pdu, name, name_length, ASN_OBJECT_ID,
buf, sizeof(oid)*tint);
} else {
result = snmp_errno;
}
}
break;
case 's':
case 'x':
case 'd':
if (check && tp->type != TYPE_OCTETSTR) {
value = "OCTET STRING";
result = SNMPERR_VALUE;
goto type_error;
}
if (type == 'd') {
if (!snmp_decimal_to_binary(&buf, &buf_len, &value_len, 1, value)) {
result = SNMPERR_VALUE;
snmp_set_detail(value);
break;
}
buf_ptr = buf;
} else if (type == 'x') {
if (!snmp_hex_to_binary(&buf, &buf_len, &value_len, 1, value)) {
result = SNMPERR_VALUE;
snmp_set_detail(value);
break;
}
buf_ptr = buf;
} else if (type == 's') {
buf_ptr = value;
value_len = strlen(value);
}
if (check && tp->ranges) {
rp = tp->ranges;
while (rp) {
if (rp->low <= value_len && value_len <= rp->high) {
break;
}
rp = rp->next;
}
if (!rp) {
result = SNMPERR_RANGE;
snmp_set_detail("Bad string length");
break;
}
}
snmp_pdu_add_variable(pdu, name, name_length, ASN_OCTET_STR,
buf_ptr, value_len);
break;
case 'n':
snmp_pdu_add_variable(pdu, name, name_length, ASN_NULL, 0, 0);
break;
case 'b':
if (check && (tp->type != TYPE_BITSTRING || !tp->enums)) {
value = "BITS";
result = SNMPERR_VALUE;
goto type_error;
}
tint = 0;
if ((buf = (u_char *)malloc(256)) == NULL) {
result = SNMPERR_MALLOC;
break;
} else {
buf_len = 256;
memset(buf, 0, buf_len);
}
for (ep = tp ? tp->enums : NULL; ep; ep = ep->next) {
if (ep->value / 8 >= (int)tint) {
tint = ep->value / 8 + 1;
}
}
for (cp = value; *cp != '\0';) {
int ix, bit;
for (; (*cp == ' ' || *cp == '\t' || *cp == ','); cp++);
if (*cp == '\0') {
break;
}
ltmp = strtoul(cp, &ecp, 0);
if (*ecp != 0) {
for (ep = tp?tp->enums:NULL; ep != NULL; ep = ep->next) {
if (strncmp(ep->label, cp, strlen(ep->label)) == 0) {
break;
}
}
if (ep != NULL) {
ltmp = ep->value;
} else {
result = SNMPERR_BAD_NAME;
snmp_set_detail(cp);
free(buf);
goto out;
}
}
ix = ltmp / 8;
if (ix >= (int)tint) {
tint = ix + 1;
}
if (ix >= buf_len && !snmp_realloc(&buf, &buf_len)) {
result = SNMPERR_MALLOC;
break;
}
bit = 0x80 >> ltmp % 8;
buf[ix] |= bit;
for (; !(*cp == ' ' || *cp == '\t' || *cp == ',' || *cp == '\0'); cp++);
}
snmp_pdu_add_variable(pdu, name, name_length, ASN_OCTET_STR,
buf, tint);
break;
#ifdef OPAQUE_SPECIAL_TYPES
case 'U':
if (read64(&c64tmp, value))
snmp_pdu_add_variable(pdu, name, name_length, ASN_OPAQUE_U64,
(u_char *) &c64tmp, sizeof(c64tmp));
else goto fail;
break;
case 'I':
if (read64(&c64tmp, value))
snmp_pdu_add_variable(pdu, name, name_length, ASN_OPAQUE_I64,
(u_char *) &c64tmp, sizeof(c64tmp));
else goto fail;
break;
case 'F':
if (sscanf(value, "%f", &ftmp) == 1)
snmp_pdu_add_variable(pdu, name, name_length, ASN_OPAQUE_FLOAT,
(u_char *) &ftmp, sizeof(ftmp));
else goto fail;
break;
case 'D':
if (sscanf(value, "%lf", &dtmp) == 1)
snmp_pdu_add_variable(pdu, name, name_length, ASN_OPAQUE_DOUBLE,
(u_char *) &dtmp, sizeof(dtmp));
else goto fail;
break;
#endif /* OPAQUE_SPECIAL_TYPES */
default:
result = SNMPERR_VAR_TYPE;
sprintf((char *)buf, "%c", type);
snmp_set_detail((char *)buf);
break;
}
SNMP_FREE(buf);
SET_SNMP_ERROR(result);
return result;
type_error:
{ char error_msg[256];
char undef_msg[32];
const char *var_type;
switch (tp->type) {
case TYPE_OBJID: var_type = "OBJECT IDENTIFIER"; break;
case TYPE_OCTETSTR: var_type = "OCTET STRING"; break;
case TYPE_INTEGER: var_type = "INTEGER"; break;
case TYPE_NETADDR: var_type = "NetworkAddress"; break;
case TYPE_IPADDR: var_type = "IpAddress"; break;
case TYPE_COUNTER: var_type = "Counter32"; break;
case TYPE_GAUGE: var_type = "Gauge32"; break;
case TYPE_TIMETICKS: var_type = "Timeticks"; break;
case TYPE_OPAQUE: var_type = "Opaque"; break;
case TYPE_NULL: var_type = "Null"; break;
case TYPE_COUNTER64: var_type = "Counter64"; break;
case TYPE_BITSTRING: var_type = "BITS"; break;
case TYPE_NSAPADDRESS: var_type = "NsapAddress"; break;
case TYPE_UINTEGER: var_type = "UInteger"; break;
case TYPE_UNSIGNED32: var_type = "Unsigned32"; break;
case TYPE_INTEGER32: var_type = "Integer32"; break;
default: sprintf(undef_msg, "TYPE_%d", tp->type); var_type = undef_msg;
}
sprintf(error_msg, "Type of attribute is %s, not %s", var_type, value);
result = SNMPERR_VAR_TYPE;
snmp_set_detail(error_msg);
goto out;
}
fail:
result = SNMPERR_VALUE;
snmp_set_detail(value);
out:
SET_SNMP_ERROR(result);
return result;
}
/*
* returns NULL or internal pointer to session
* use this pointer for the other snmp_sess* routines,
* which guarantee action will occur ONLY for this given session.
*/
void *
snmp_sess_pointer(struct snmp_session *session)
{
struct session_list *slp;
snmp_res_lock(MT_LIBRARY_ID, MT_LIB_SESSION);
for(slp = Sessions; slp; slp = slp->next){
if (slp->session == session){
break;
}
}
snmp_res_unlock(MT_LIBRARY_ID, MT_LIB_SESSION);
if (slp == NULL) {
snmp_errno = SNMPERR_BAD_SESSION; /*MTCRITICAL_RESOURCE*/
return(NULL);
}
return((void *)slp);
}
/*
* Input : an opaque pointer, returned by snmp_sess_open.
* returns NULL or pointer to session.
*/
struct snmp_session *
snmp_sess_session(void *sessp)
{
struct session_list *slp = (struct session_list *)sessp;
if (slp == NULL) return(NULL);
return (slp->session);
}
/* snmp_sess_transport: takes an opaque pointer (as returned by
snmp_sess_open or snmp_sess_pointer) and returns the corresponding
snmp_transport pointer (or NULL if the opaque pointer does not correspond
to an active internal session). */
snmp_transport *
snmp_sess_transport (void *sessp)
{
struct session_list *slp = (struct session_list *)sessp;
if (slp == NULL) {
return NULL;
} else {
return slp->transport;
}
}
/* snmp_sess_transport_set: set the transport pointer for the opaque
session pointer sp. */
void
snmp_sess_transport_set (void *sp, snmp_transport *t)
{
struct session_list *slp = (struct session_list *)sp;
if (slp != NULL) {
slp->transport = t;
}
}
#ifdef CMU_COMPATIBLE
char *
snmp_pdu_type(struct snmp_pdu *PDU)
{
switch(PDU->command) {
case SNMP_MSG_GET:
return("GET");
break;
case SNMP_MSG_GETNEXT:
return("GETNEXT");
break;
case SNMP_MSG_RESPONSE:
return("RESPONSE");
break;
case SNMP_MSG_SET:
return("SET");
break;
case SNMP_MSG_GETBULK:
return("GETBULK");
break;
case SNMP_MSG_INFORM:
return("INFORM");
break;
case SNMP_MSG_TRAP2:
return("V2TRAP");
break;
case SNMP_MSG_REPORT:
return("REPORT");
break;
case SNMP_MSG_TRAP:
return("V1TRAP");
break;
default:
return("Unknown");
break;
}
}
/*
* cmu_snmp_parse - emulate CMU library's snmp_parse.
*
* Parse packet, storing results into PDU.
* Returns community string if success, NULL if fail.
* WARNING: may return a zero length community string.
*
* Note:
* Some CMU-aware apps call init_mib(), but do not
* initialize a session.
* Check Reqid to make sure that this module is initialized.
*/
u_char *
cmu_snmp_parse (struct snmp_session *session,
struct snmp_pdu *pdu,
u_char *data,
size_t length)
{
u_char *bufp = NULL;
if (Reqid == 0) {
snmp_sess_init(session); /* gimme a break! */
}
switch(pdu->version) {
case SNMP_VERSION_1:
case SNMP_VERSION_2c:
case SNMP_DEFAULT_VERSION:
break;
default:
return NULL;
}
#ifndef NO_INTERNAL_VARLIST
if (snmp_parse( 0, session, pdu, data, length) != SNMP_ERR_NOERROR){
return NULL;
}
#else
/*
* while there are two versions of variable_list:
* use an internal variable list for snmp_parse;
* clone the result.
*/
if (1) {
struct snmp_pdu *snmp_clone_pdu (struct snmp_pdu *);
struct snmp_pdu *snmp_2clone_pdu(struct snmp_pdu *from_pdu, struct snmp_pdu *to_pdu);
struct snmp_pdu *ipdu;
ipdu = snmp_clone_pdu(pdu);
if (snmp_parse( 0, session, ipdu, data, length) != SNMP_ERR_NOERROR){
snmp_free_internal_pdu(ipdu);
return NULL;
}
pdu = snmp_2clone_pdu(ipdu, pdu);
snmp_free_internal_pdu(ipdu);
}
#endif /* NO_INTERNAL_VAR_LIST */
/* Add a null to meet the caller's expectations. */
bufp = (u_char *)malloc(1+pdu->community_len);
if (bufp && pdu->community_len) {
memcpy(bufp, pdu->community, pdu->community_len);
bufp[pdu->community_len] = '\0';
}
return(bufp);
}
#endif /* CMU_COMPATIBLE */
/* snmp_duplicate_objid: duplicates (mallocs) an objid based on the
input objid */
oid *
snmp_duplicate_objid(oid *objToCopy, size_t objToCopyLen)
{
oid *returnOid;
returnOid = (oid *) malloc(objToCopyLen*sizeof(oid));
if (returnOid) {
memmove(returnOid, objToCopy, objToCopyLen*sizeof(oid));
}
return returnOid;
}
/* generic statistics counter functions */
static u_int statistics[MAX_STATS];
u_int
snmp_increment_statistic(int which)
{
if (which >= 0 && which < MAX_STATS) {
statistics[which]++;
return statistics[which];
}
return 0;
}
u_int
snmp_increment_statistic_by(int which, int count)
{
if (which >= 0 && which < MAX_STATS) {
statistics[which] += count;
return statistics[which];
}
return 0;
}
u_int
snmp_get_statistic(int which)
{
if (which >= 0 && which < MAX_STATS)
return statistics[which];
return 0;
}
void
snmp_init_statistics(void)
{
memset(statistics, 0, sizeof(statistics));
}
/*
* For compatibility with applications built using
* previous versions only.
*/
/* use <struct snmp_session *)->s_snmp_errno instead */
int snmp_get_errno (void) { return SNMPERR_SUCCESS; }
/* synch_reset and synch_setup are no longer used. */
void snmp_synch_reset (struct snmp_session * notused) {}
void snmp_synch_setup (struct snmp_session * notused) {}
/* provide for backwards compatibility */
void
snmp_set_dump_packet(int x) {
ds_set_boolean(DS_LIBRARY_ID, DS_LIB_DUMP_PACKET, x);
}
int
snmp_get_dump_packet(void) {
return ds_get_boolean(DS_LIBRARY_ID, DS_LIB_DUMP_PACKET);
}
void
snmp_set_quick_print(int x) {
ds_set_boolean(DS_LIBRARY_ID, DS_LIB_QUICK_PRINT, x);
}
int
snmp_get_quick_print(void) {
return ds_get_boolean(DS_LIBRARY_ID, DS_LIB_QUICK_PRINT);
}
void
snmp_set_suffix_only(int x) {
ds_set_int(DS_LIBRARY_ID, DS_LIB_PRINT_SUFFIX_ONLY, x);
}
int
snmp_get_suffix_only(void) {
return ds_get_int(DS_LIBRARY_ID, DS_LIB_PRINT_SUFFIX_ONLY);
}
void
snmp_set_full_objid(int x) {
ds_set_boolean(DS_LIBRARY_ID, DS_LIB_PRINT_FULL_OID, x);
}
int
snmp_get_full_objid(void) {
return ds_get_boolean(DS_LIBRARY_ID, DS_LIB_PRINT_SUFFIX_ONLY);
}
void
snmp_set_random_access(int x) {
ds_set_boolean(DS_LIBRARY_ID, DS_LIB_RANDOM_ACCESS, x);
}
int
snmp_get_random_access(void) {
return ds_get_boolean(DS_LIBRARY_ID, DS_LIB_RANDOM_ACCESS);
}