6790812000-12-05Honza Petrous //: SNMP protocol implementation for Pike //: //: Honza Petrous, 2000-10-07 (on the 'coding party' after user conference :) //: //: RFC: //: implemented (yet): //: 1157 - v1 (only `TRAP' PDU is missing) //: planned: //: 1901 - v2/community //: 2570 - v3 description //: //: For debuging use -DDEBUG_PIKE_PROTOCOL_SNMP=1 #include "snmp_globals.h" #include "snmp_errors.h" #if 1 // --- ASN.1 hack class asn1_application_octet_string { inherit Standards.ASN1.Types.asn1_octet_string; constant cls = 1; constant type_name = "APPLICATION OCTET_STRING"; int tagx; int get_tag() { return tagx; } void init(int tagid, string arg) { ::value = arg; tagx = tagid; } } class asn1_application_integer { inherit Standards.ASN1.Types.asn1_integer; constant cls = 1; constant type_name = "APPLICATION INTEGER"; int tagx; int get_tag() { return tagx; } void init(int tagid, int arg) { ::init(arg); tagx = tagid; } } object|mapping der_decode(object data, mapping types) { int raw_tag = data->get_uint(1); int len; string contents; if ( (raw_tag & 0x1f) == 0x1f) error("ASN1.Decode: High tag numbers is not supported\n"); len = data->get_uint(1); if (len & 0x80) len = data->get_uint(len & 0x7f); contents = data->get_fix_string(len); int tag = raw_tag & 0xdf; // Class and tag bits program p = types[tag]; if (raw_tag & 0x20) { /* Constructed encoding */ array elements = ({ }); object struct = ADT.struct(contents); if (!p) { while (!struct->is_empty()) elements += ({ der_decode(struct, types) }); return Standards.ASN1.Decode.constructed(tag, contents, elements); } object res = p(); // hop: For non-universal classes we provide tag number if(tag & 0xC0) res = p(tag & 0x1F, ({})); res->begin_decode_constructed(contents); int i; /* Ask object which types it expects for field i, decode it, and * record the decoded object */ for(i = 0; !struct->is_empty(); i++) { res->decode_constructed_element (i, der_decode(struct, res->element_types(i, types))); } return res->end_decode_constructed(i); } else { /* Primitive encoding */ return p ? p()->decode_primitive(contents) : Standards.ASN1.Decode.primitive(tag, contents); } } static mapping snmp_type_proc = ([ 1 : Standards.ASN1.Types.asn1_boolean, 2 : Standards.ASN1.Types.asn1_integer, 3 : Standards.ASN1.Types.asn1_bit_string, 4 : Standards.ASN1.Types.asn1_octet_string, 5 : Standards.ASN1.Types.asn1_null, 6 : Standards.ASN1.Types.asn1_identifier, // 9 : asn1_real, //10 : asn1_enumerated, 16 : Standards.ASN1.Types.asn1_sequence, 17 : Standards.ASN1.Types.asn1_set, 19 : Standards.ASN1.Types.asn1_printable_string, 20 : Standards.ASN1.Types.asn1_teletex_string, 23 : Standards.ASN1.Types.asn1_utc, // from RFC-1065 : 64 : asn1_application_octet_string, // ipaddress 65 : asn1_application_integer, // counter 66 : asn1_application_integer, // gauge 67 : asn1_application_integer, // timeticks 68 : asn1_application_octet_string // opaque ]); object|mapping snmp_der_decode(string data) { return /*Standards.ASN1.Decode.*/der_decode(ADT.struct(data), snmp_type_proc); } // --- end of hack #endif inherit Stdio.UDP : snmp; //: //: public vars //: //: //: private variables //: int port = SNMP_DEFAULT_PORT; string local_host = SNMP_DEFAULT_HOST; string remote_host; int request_id = 1; int next_id = 1; int snmp_version = SNMP_DEFAULT_VERSION; string snmp_community = SNMP_DEFAULT_COMMUNITY; int snmp_errno = SNMP_SUCCESS; int ok; //: //: msg pool //: mapping msgpool = ([]); //: //: callback support //: function con_ok, con_fail; array extra_args; //: //: create //: //: *_port: local and remote UDP port //: *_addr: local and remote address //: void create(int|void rem_port, string|void rem_addr, int|void loc_port, string|void loc_addr) { int lport = loc_port; local_host = (!loc_addr || !sizeof(loc_addr)) ? SNMP_DEFAULT_LOCHOST : loc_addr; if(stringp(rem_addr) && sizeof(rem_addr)) remote_host = rem_addr; if (!snmp::bind(lport, local_host)) { //# error ... DWRITE("protocol.create: can't bind to the socket.\n"); ok = 0; if(con_fail) con_fail(this_object(), @extra_args); } if(snmp_errno) THROW(({"Failed to bind to SNMP port.\n", backtrace()})); DWRITE("protocol.bind: success!\n"); DWRITE(sprintf("protocol.create: local adress:port binded: [%s:%d].\n", local_host, lport)); } mapping readmsg() { //: returns the whole SNMP message in raw format mapping rv; #if 1 rv = read(); #else if(catch { rv = read(); }) { //seterr or _READ_ERROR ? THROW(({"SNMP.protocol: read error.\n",backtrace()})); } #endif return(rv); } void to_pool(mapping rawd) { //: decode ASN1 data and put it into pool, if garbaged ignore it object xdec = snmp_der_decode(rawd->data); string msgid = (string)xdec->elements[2]->elements[0]->value; int errno = xdec->elements[2]->elements[1]->value; mapping msg = ([ "ip":rawd->ip, "port":rawd->port, "error-status":errno, "error-string":snmp_errlist[errno], "error-index":xdec->elements[2]->elements[2]->value, "attribute":Array.map(xdec->elements[2]->elements[3]->elements, lambda(object duo) { return(([(array(string))(duo->elements[0]->id)*".":duo->elements[1]->value])); } ) ]); // to the queue msgpool += ([msgid:msg]); } mapping|int from_pool(string msgid) { //: get data from poll mapping msg; if(zero_type(msgpool[msgid])) return 0; msg = msgpool[msgid]; msgpool -= ([msgid:msg]); return(msg); } mapping readmsg_from_pool(int msgid) { //: read SNMP response PDU from PDU pool mapping rv = from_pool((string)msgid); if(rv) return(rv); #define HACK 1 #ifdef HACK mapping tmpm = readmsg(); to_pool(tmpm); #endif return(from_pool((string)msgid)); } int writemsg(string rem_addr, int rem_port, object pdu) { //: send SNMP encoded message and return status //: OK, in most cases :) object msg; string rawd; int msize; msg = Standards.ASN1.Types.asn1_sequence(({ Standards.ASN1.Types.asn1_integer(snmp_version-1), Standards.ASN1.Types.asn1_octet_string(snmp_community), pdu})); rawd = msg->get_der(); DWRITE(sprintf("protocol.writemsg: %O\n", rawd)); msize = send(rem_addr, rem_port, rawd); return(msize = sizeof(rawd) ? SNMP_SUCCESS : SNMP_SEND_ERROR); } int get_req_id() { //: returns unicate id //LOCK int rv = request_id++; //UNLOCK return(rv); } //: //: get_response //: array(mapping)|int get_response(int msgid) { //: GetResponse-PDU low call mapping rawpdu = readmsg_from_pool(msgid); return(({rawpdu})); } //: //: get_request //: int get_request(array(string) varlist, string|void rem_addr, int|void rem_port) { //: GetRequest-PDU low call object pdu; int id = get_req_id(), flg; array vararr = ({}); foreach(varlist, string varname) vararr += ({Standards.ASN1.Types.asn1_sequence( ({Standards.ASN1.Types.asn1_identifier(@Array.map(varname/".", lambda(string el){ return((int)el);})), Standards.ASN1.Types.asn1_integer(1)}) //doesn't sense but req )}); pdu = Protocols.LDAP.ldap_privates.asn1_context_sequence(0, ({Standards.ASN1.Types.asn1_integer(id), // request-id Standards.ASN1.Types.asn1_integer(0), // error-status Standards.ASN1.Types.asn1_integer(0), // error-index Standards.ASN1.Types.asn1_sequence(vararr)}) ); // now we have PDU ... flg = writemsg(rem_addr||remote_host, rem_port || port, pdu); return id; } //: //: get_nextrequest //: int get_nextrequest(array(string) varlist, string|void rem_addr, int|void rem_port) { //: GetNextRequest-PDU low call object pdu; int id = get_req_id(), flg; array vararr = ({}); foreach(varlist, string varname) vararr += ({Standards.ASN1.Types.asn1_sequence( ({Standards.ASN1.Types.asn1_identifier(@Array.map(varname/".", lambda(string el){ return((int)el);})), Standards.ASN1.Types.asn1_integer(1)}) //doesn't sense but req )}); pdu = Protocols.LDAP.ldap_privates.asn1_context_sequence(1, ({Standards.ASN1.Types.asn1_integer(id), // request-id Standards.ASN1.Types.asn1_integer(0), // error-status Standards.ASN1.Types.asn1_integer(0), // error-index Standards.ASN1.Types.asn1_sequence(vararr)}) ); // now we have PDU ... flg = writemsg(rem_addr||remote_host, rem_port || port, pdu); return id; } object mktype(array(mixed) varval) { if(sizeof(varval) != 2) // error! return 0; switch(varval[0]) { case "i": // integer return Standards.ASN1.Types.asn1_integer(varval[1]); case "s": // string return Standards.ASN1.Types.asn1_octet_string(varval[1]); } return 0; } //: //: set_request //: int set_request(mapping varlist, string|void rem_addr, int|void rem_port) { //: SetRequest-PDU low call object pdu; int id = get_req_id(), flg; array vararr = ({}); foreach(indices(varlist), string varname) vararr += ({Standards.ASN1.Types.asn1_sequence( ({Standards.ASN1.Types.asn1_identifier(@Array.map(varname/".", lambda(string el){ return((int)el);})), mktype(varlist[varname])}) )}); pdu = Protocols.LDAP.ldap_privates.asn1_context_sequence(3, ({Standards.ASN1.Types.asn1_integer(id), // request-id Standards.ASN1.Types.asn1_integer(0), // error-status Standards.ASN1.Types.asn1_integer(0), // error-index Standards.ASN1.Types.asn1_sequence(vararr)}) ); // now we have PDU ... flg = writemsg(rem_addr||remote_host, rem_port || port, pdu); return id; }