/* * Convert variable bindings from AgentX to SNMP dialect. */ int varbind_convert(struct agentx_pdu *pdu, struct agentx_varbind_hdr *vbhdr, struct ber_element **varbind, struct ber_element **iter) { struct ber_oid oid; u_int32_t d; u_int64_t l; int slen; char *str; struct ber_element *a; int ret = AGENTX_ERR_NONE; if (snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1) { ret = AGENTX_ERR_PARSE_ERROR; goto done; } *iter = ber_add_sequence(*iter); if (*varbind == NULL) *varbind = *iter; a = ber_add_oid(*iter, &oid); switch (vbhdr->type) { case AGENTX_NO_SUCH_OBJECT: case AGENTX_NO_SUCH_INSTANCE: case AGENTX_END_OF_MIB_VIEW: case AGENTX_NULL: a = ber_add_null(a); break; case AGENTX_IP_ADDRESS: case AGENTX_OPAQUE: case AGENTX_OCTET_STRING: str = snmp_agentx_read_octetstr(pdu, &slen); if (str == NULL) { ret = AGENTX_ERR_PARSE_ERROR; goto done; } a = ber_add_nstring(a, str, slen); break; case AGENTX_OBJECT_IDENTIFIER: if (snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1) { ret = AGENTX_ERR_PARSE_ERROR; goto done; } a = ber_add_oid(a, &oid); break; case AGENTX_INTEGER: case AGENTX_COUNTER32: case AGENTX_GAUGE32: case AGENTX_TIME_TICKS: if (snmp_agentx_read_int(pdu, &d) == -1) { ret = AGENTX_ERR_PARSE_ERROR; goto done; } a = ber_add_integer(a, d); break; case AGENTX_COUNTER64: if (snmp_agentx_read_int64(pdu, &l) == -1) { ret = AGENTX_ERR_PARSE_ERROR; goto done; } a = ber_add_integer(a, l); break; default: log_debug("unknown data type '%i'", vbhdr->type); ret = AGENTX_ERR_PARSE_ERROR; goto done; } /* AgentX types correspond to BER types */ switch (vbhdr->type) { case BER_TYPE_INTEGER: case BER_TYPE_BITSTRING: case BER_TYPE_OCTETSTRING: case BER_TYPE_NULL: case BER_TYPE_OBJECT: /* universal types */ break; /* Convert AgentX error types to SNMP error types */ case AGENTX_NO_SUCH_OBJECT: ber_set_header(a, BER_CLASS_CONTEXT, 0); break; case AGENTX_NO_SUCH_INSTANCE: ber_set_header(a, BER_CLASS_CONTEXT, 1); break; case AGENTX_COUNTER32: ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER32); break; case AGENTX_GAUGE32: ber_set_header(a, BER_CLASS_APPLICATION, SNMP_GAUGE32); break; case AGENTX_COUNTER64: ber_set_header(a, BER_CLASS_APPLICATION, SNMP_COUNTER64); break; case AGENTX_IP_ADDRESS: /* application 0 implicit 4-byte octet string per SNMPv2-SMI */ break; default: /* application-specific types */ ber_set_header(a, BER_CLASS_APPLICATION, vbhdr->type); break; } done: return (ret); }
/* ARGSUSED */ void control_dispatch_agentx(int fd, short event, void *arg) { struct ctl_conn *c = arg; struct agentx_handle *h = c->handle; struct agentx_pdu *pdu; struct timeval tv; struct agentx_open_timeout to; struct ber_oid oid; struct agentx_close_request_data clhdr; int closing = 0; int evflags = 0; int timer = 0; int error = AGENTX_ERR_NONE; int idx = 0, vcpylen, dlen, uptime; char *descr, *varcpy; varcpy = descr = NULL; if (h->timeout != 0) tv.tv_sec = h->timeout; else tv.tv_sec = AGENTX_DEFAULT_TIMEOUT; tv.tv_usec = 0; if (event & EV_TIMEOUT) { log_info("subagent session '%i' timed out after %i seconds", h->sessionid, h->timeout); goto teardown; } if (event & EV_WRITE) { if (snmp_agentx_send(h, NULL) == -1) { if (errno != EAGAIN) goto teardown; /* short write */ evflags |= EV_WRITE; timer = 1; } } if (event & EV_READ) { if ((pdu = snmp_agentx_recv(h)) == NULL) { if (h->error) { error = h->error; goto respond; } if (errno != EAGAIN) goto teardown; /* short read */ timer = 1; goto done; } switch (pdu->hdr->type) { case AGENTX_OPEN: if (snmp_agentx_read_raw(pdu, &to, sizeof(to)) == -1 || snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1 || (descr = snmp_agentx_read_octetstr(pdu, &dlen)) == NULL) { error = AGENTX_ERR_PARSE_ERROR; break; } log_info("opening AgentX socket for '%.*s'", dlen, descr); h->sessionid = pdu->hdr->sessionid = agentx_sessionid++; if (to.timeout != 0) h->timeout = to.timeout; else h->timeout = AGENTX_DEFAULT_TIMEOUT; break; case AGENTX_CLOSE: if (snmp_agentx_read_raw(pdu, &clhdr, sizeof(clhdr)) == -1) { error = AGENTX_ERR_PARSE_ERROR; break; } closing = 1; break; case AGENTX_NOTIFY: error = trap_agentx(h, pdu, &idx, &varcpy, &vcpylen); break; case AGENTX_PING: /* no processing, just an empty response */ break; case AGENTX_REGISTER: { struct agentx_register_hdr rhdr; struct oidlist oids; struct oid *miboid; uint32_t ubound = 0; TAILQ_INIT(&oids); if (snmp_agentx_read_raw(pdu, &rhdr, sizeof(rhdr)) == -1 || snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1) { error = AGENTX_ERR_PARSE_ERROR; break; } do { if ((miboid = calloc(1, sizeof(*miboid))) == NULL) { purge_registered_oids(&oids); error = AGENTX_ERR_PARSE_ERROR; goto dodone; } bcopy(&oid, &miboid->o_id, sizeof(oid)); miboid->o_flags = OID_RD|OID_WR|OID_REGISTERED; miboid->o_session = c; if (smi_insert(miboid) == -1) { purge_registered_oids(&oids); error = AGENTX_ERR_DUPLICATE_REGISTRATION; goto dodone; } TAILQ_INSERT_TAIL(&oids, miboid, o_list); } while (++oid.bo_id[rhdr.subrange] <= ubound); while ((miboid = TAILQ_FIRST(&oids)) != NULL) { TAILQ_REMOVE(&oids, miboid, o_list); TAILQ_INSERT_TAIL(&c->oids, miboid, o_list); } dodone: break; } case AGENTX_UNREGISTER: { struct agentx_unregister_hdr uhdr; struct oid *miboid; uint32_t ubound = 0; if (snmp_agentx_read_raw(pdu, &uhdr, sizeof(uhdr)) == -1 || snmp_agentx_read_oid(pdu, (struct snmp_oid *)&oid) == -1) { error = AGENTX_ERR_PARSE_ERROR; break; } do { if ((miboid = smi_find((struct oid *)&oid)) == NULL) { log_warnx("attempting to remove unregistered MIB"); continue; } if (miboid->o_session != c) { log_warnx("attempting to remove MIB registered by other session"); continue; } smi_delete(miboid); } while (++oid.bo_id[uhdr.subrange] <= ubound); break; } case AGENTX_RESPONSE: { struct snmp_message *msg = pdu->request->cookie; struct agentx_response_data resp; struct agentx_varbind_hdr vbhdr; struct ber_element **elm, **iter; if (snmp_agentx_read_response(pdu, &resp) == -1) { msg->sm_error = SNMP_ERROR_GENERR; goto dispatch; } switch (resp.error) { case AGENTX_ERR_NONE: break; /* per RFC, resp.error may be an SNMP error value */ case SNMP_ERROR_TOOBIG: case SNMP_ERROR_NOSUCHNAME: case SNMP_ERROR_BADVALUE: case SNMP_ERROR_READONLY: case SNMP_ERROR_GENERR: case SNMP_ERROR_NOACCESS: case SNMP_ERROR_WRONGTYPE: case SNMP_ERROR_WRONGLENGTH: case SNMP_ERROR_WRONGENC: case SNMP_ERROR_WRONGVALUE: case SNMP_ERROR_NOCREATION: case SNMP_ERROR_INCONVALUE: case SNMP_ERROR_RESUNAVAIL: case SNMP_ERROR_COMMITFAILED: case SNMP_ERROR_UNDOFAILED: case SNMP_ERROR_AUTHERROR: case SNMP_ERROR_NOTWRITABLE: case SNMP_ERROR_INCONNAME: msg->sm_error = resp.error; msg->sm_errorindex = resp.index; break; case AGENTX_ERR_INDEX_WRONG_TYPE: case AGENTX_ERR_UNSUPPORTED_CONTEXT: case AGENTX_ERR_PARSE_ERROR: case AGENTX_ERR_REQUEST_DENIED: case AGENTX_ERR_PROCESSING_ERROR: default: msg->sm_error = SNMP_ERROR_GENERR; msg->sm_errorindex = resp.index; break; } iter = elm = &msg->sm_varbindresp; while (pdu->datalen > sizeof(struct agentx_hdr)) { if (snmp_agentx_read_raw(pdu, &vbhdr, sizeof(vbhdr)) == -1 || varbind_convert(pdu, &vbhdr, elm, iter) != AGENTX_ERR_NONE) { msg->sm_error = SNMP_ERROR_GENERR; msg->sm_errorindex = msg->sm_i; goto dispatch; } } dispatch: snmpe_dispatchmsg(msg); break; } /* unimplemented, but parse and accept for now */ case AGENTX_ADD_AGENT_CAPS: case AGENTX_REMOVE_AGENT_CAPS: break; /* unimplemented */ case AGENTX_GET: case AGENTX_GET_NEXT: case AGENTX_GET_BULK: case AGENTX_TEST_SET: case AGENTX_COMMIT_SET: case AGENTX_UNDO_SET: case AGENTX_CLEANUP_SET: case AGENTX_INDEX_ALLOCATE: case AGENTX_INDEX_DEALLOCATE: error = AGENTX_ERR_REQUEST_DENIED; break; /* NB: by RFC, this should precede all other checks. */ default: log_info("unknown AgentX type '%i'", pdu->hdr->type); error = AGENTX_ERR_PARSE_ERROR; break; } respond: if (pdu) snmp_agentx_pdu_free(pdu); uptime = smi_getticks(); if ((pdu = snmp_agentx_response_pdu(uptime, error, idx)) == NULL) { log_debug("failed to generate response"); free(varcpy); control_event_add(c, fd, EV_WRITE, NULL); /* XXX -- EV_WRITE? */ return; } if (varcpy) { snmp_agentx_raw(pdu, varcpy, vcpylen); /* XXX */ free(varcpy); } snmp_agentx_send(h, pdu); /* Request processed, now write out response */ evflags |= EV_WRITE; } if (closing) goto teardown; done: control_event_add(c, fd, evflags, timer ? &tv : NULL); return; teardown: log_debug("subagent session '%i' destroyed", h->sessionid); snmp_agentx_free(h); purge_registered_oids(&c->oids); free(varcpy); control_close(c, "agentx teardown", NULL); }