Sergey Pastor
Webserver+3d print
Diff: cyclone_tcp/snmp/snmp_agent_pdu.c
- Revision:
- 0:8918a71cdbe9
diff -r 000000000000 -r 8918a71cdbe9 cyclone_tcp/snmp/snmp_agent_pdu.c
--- /dev/null Thu Jan 01 00:00:00 1970 +0000
+++ b/cyclone_tcp/snmp/snmp_agent_pdu.c Sat Feb 04 18:15:49 2017 +0000
@@ -0,0 +1,1075 @@
+/**
+ * @file snmp_agent_pdu.c
+ * @brief SNMP agent (PDU processing)
+ *
+ * @section License
+ *
+ * Copyright (C) 2010-2017 Oryx Embedded SARL. All rights reserved.
+ *
+ * This file is part of CycloneTCP Open.
+ *
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * @author Oryx Embedded SARL (www.oryx-embedded.com)
+ * @version 1.7.6
+ **/
+
+//Switch to the appropriate trace level
+#define TRACE_LEVEL SNMP_TRACE_LEVEL
+
+//Dependencies
+#include "core/net.h"
+#include "snmp/snmp_agent.h"
+#include "snmp/snmp_agent_pdu.h"
+#include "snmp/snmp_agent_misc.h"
+#include "mibs/mib2_module.h"
+#include "crypto.h"
+#include "asn1.h"
+#include "oid.h"
+#include "debug.h"
+
+//Check TCP/IP stack configuration
+#if (SNMP_AGENT_SUPPORT == ENABLED)
+
+//sysUpTime.0 object (1.3.6.1.2.1.1.3.0)
+static const uint8_t sysUpTimeObject[] = {43, 6, 1, 2, 1, 1, 3, 0};
+//snmpTrapOID.0 object (1.3.6.1.6.3.1.1.4.1.0)
+static const uint8_t snmpTrapOidObject[] = {43, 6, 1, 6, 3, 1, 1, 4, 1, 0};
+//snmpTraps object (1.3.6.1.6.3.1.1.5)
+static const uint8_t snmpTrapsObject[] = {43, 6, 1, 6, 3, 1, 1, 5};
+
+
+/**
+ * @brief Process PDU
+ * @param[in] context Pointer to the SNMP agent context
+ * @return Error code
+ **/
+
+error_t snmpProcessPdu(SnmpAgentContext *context)
+{
+ error_t error;
+
+ //Parse PDU header
+ error = snmpParsePduHeader(&context->request);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Check PDU type
+ switch(context->request.pduType)
+ {
+ case SNMP_PDU_GET_REQUEST:
+ case SNMP_PDU_GET_NEXT_REQUEST:
+ //Process GetRequest-PDU or GetNextRequest-PDU
+ error = snmpProcessGetRequestPdu(context);
+ break;
+ case SNMP_PDU_GET_BULK_REQUEST:
+ //Process GetBulkRequest-PDU
+ error = snmpProcessGetBulkRequestPdu(context);
+ break;
+ case SNMP_PDU_SET_REQUEST:
+ //Process SetRequest-PDU
+ error = snmpProcessSetRequestPdu(context);
+ break;
+ default:
+ //Invalid PDU type
+ error = ERROR_INVALID_TYPE;
+ break;
+ }
+
+ //Check status code
+ if(!error)
+ {
+ //Total number of SNMP Get-Response PDUs which have been generated
+ //by the SNMP protocol entity
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpOutGetResponses, 1);
+
+ //Format PDU header
+ error = snmpWritePduHeader(&context->response);
+ }
+
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Process GetRequest-PDU or GetNextRequest-PDU
+ * @param[in] context Pointer to the SNMP agent context
+ * @return Error code
+ **/
+
+error_t snmpProcessGetRequestPdu(SnmpAgentContext *context)
+{
+ error_t error;
+ int_t index;
+ size_t n;
+ size_t length;
+ const uint8_t *p;
+ SnmpVarBind var;
+
+ //Check PDU type
+ if(context->request.pduType == SNMP_PDU_GET_REQUEST)
+ {
+ //Debug message
+ TRACE_INFO("Parsing GetRequest-PDU...\r\n");
+
+ //Total number of SNMP Get-Request PDUs which have been accepted and
+ //processed by the SNMP protocol entity
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInGetRequests, 1);
+ }
+ else if(context->request.pduType == SNMP_PDU_GET_NEXT_REQUEST)
+ {
+ //Debug message
+ TRACE_INFO("Parsing GetNextRequest-PDU...\r\n");
+
+ //Total number of SNMP Get-NextRequest PDUs which have been accepted
+ //and processed by the SNMP protocol entity
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInGetNexts, 1);
+ }
+
+ //Enforce access policy
+ if(context->user->mode != SNMP_ACCESS_READ_ONLY &&
+ context->user->mode != SNMP_ACCESS_READ_WRITE)
+ {
+ //Total number of SNMP messages delivered to the SNMP protocol entity
+ //which represented an SNMP operation which was not allowed by the SNMP
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInBadCommunityUses, 1);
+
+ //Report an error
+ return ERROR_ACCESS_DENIED;
+ }
+
+ //Initialize response message
+ error = snmpInitResponse(context);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Point to the first variable binding of the request
+ p = context->request.varBindList;
+ length = context->request.varBindListLen;
+
+ //Lock access to MIB bases
+ snmpLockMib(context);
+
+ //Loop through the list
+ for(index = 1; length > 0; index++)
+ {
+ //Parse variable binding
+ error = snmpParseVarBinding(p, length, &var, &n);
+ //Failed to parse variable binding?
+ if(error)
+ break;
+
+ //Make sure that the object identifier is valid
+ error = oidCheck(var.oid, var.oidLen);
+ //Invalid object identifier?
+ if(error)
+ break;
+
+ //GetRequest-PDU?
+ if(context->request.pduType == SNMP_PDU_GET_REQUEST)
+ {
+ //Retrieve object value
+ error = snmpGetObjectValue(context, &var);
+ }
+ //GetNextRequest-PDU?
+ else
+ {
+ //Search the MIB for the next object
+ error = snmpGetNextObject(context, &var);
+
+ //SNMPv1 version?
+ if(context->request.version == SNMP_VERSION_1)
+ {
+ //Check status code
+ if(error == NO_ERROR)
+ {
+ //Retrieve object value
+ error = snmpGetObjectValue(context, &var);
+ }
+ else
+ {
+ //Stop immediately
+ break;
+ }
+ }
+ //SNMPv2c or SNMPv3 version?
+ else
+ {
+ //Check status code
+ if(error == NO_ERROR)
+ {
+ //Retrieve object value
+ error = snmpGetObjectValue(context, &var);
+ }
+ else if(error == ERROR_OBJECT_NOT_FOUND)
+ {
+ //The variable binding's value field is set to endOfMibView
+ var.objClass = ASN1_CLASS_CONTEXT_SPECIFIC;
+ var.objType = SNMP_EXCEPTION_END_OF_MIB_VIEW;
+ var.valueLen = 0;
+
+ //Catch exception
+ error = NO_ERROR;
+ }
+ else
+ {
+ //Stop immediately
+ break;
+ }
+ }
+ }
+
+ //Failed to retrieve object value?
+ if(error)
+ {
+ //SNMPv1 version?
+ if(context->request.version == SNMP_VERSION_1)
+ {
+ //Stop immediately
+ break;
+ }
+ //SNMPv2c or SNMPv3 version?
+ else
+ {
+ //Catch exception
+ if(error == ERROR_ACCESS_DENIED ||
+ error == ERROR_OBJECT_NOT_FOUND)
+ {
+ //The variable binding's value field is set to noSuchObject
+ var.objClass = ASN1_CLASS_CONTEXT_SPECIFIC;
+ var.objType = SNMP_EXCEPTION_NO_SUCH_OBJECT;
+ var.valueLen = 0;
+ }
+ else if(error == ERROR_INSTANCE_NOT_FOUND)
+ {
+ //The variable binding's value field is set to noSuchInstance
+ var.objClass = ASN1_CLASS_CONTEXT_SPECIFIC;
+ var.objType = SNMP_EXCEPTION_NO_SUCH_INSTANCE;
+ var.valueLen = 0;
+ }
+ else
+ {
+ //Stop immediately
+ break;
+ }
+ }
+ }
+ else
+ {
+ //Total number of MIB objects which have been retrieved successfully
+ //by the SNMP protocol entity as the result of receiving valid SNMP
+ //Get-Request and Get-NextRequest PDUs
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInTotalReqVars, 1);
+ }
+
+ //Append variable binding to the list
+ error = snmpWriteVarBinding(context, &var);
+ //Any error to report?
+ if(error)
+ break;
+
+ //Advance data pointer
+ p += n;
+ length -= n;
+ }
+
+ //Unlock access to MIB bases
+ snmpUnlockMib(context);
+
+ //Check status code
+ if(error)
+ {
+ //Set error-status and error-index fields
+ error = snmpTranslateStatusCode(&context->response, error, index);
+ //If the parsing of the request fails, the SNMP agent discards the message
+ if(error)
+ return error;
+
+ //Check whether an alternate Response-PDU should be sent
+ if(context->response.version != SNMP_VERSION_1 &&
+ context->response.errorStatus == SNMP_ERROR_TOO_BIG)
+ {
+ //The alternate Response-PDU is formatted with the same value in its
+ //request-id field as the received GetRequest-PDU and an empty
+ //variable-bindings field
+ context->response.varBindListLen = 0;
+ }
+ else
+ {
+ //The Response-PDU is re-formatted with the same values in its request-id
+ //and variable-bindings fields as the received GetRequest-PDU
+ error = snmpCopyVarBindingList(context);
+ //Any error to report?
+ if(error)
+ return error;
+ }
+ }
+
+ //Successful processing
+ return NO_ERROR;
+}
+
+
+/**
+ * @brief Process GetBulkRequest-PDU
+ * @param[in] context Pointer to the SNMP agent context
+ * @return Error code
+ **/
+
+error_t snmpProcessGetBulkRequestPdu(SnmpAgentContext *context)
+{
+#if (SNMP_V2C_SUPPORT == ENABLED || SNMP_V3_SUPPORT == ENABLED)
+ error_t error;
+ int_t index;
+ size_t n;
+ size_t m;
+ size_t length;
+ bool_t endOfMibView;
+ const uint8_t *p;
+ const uint8_t *next;
+ SnmpVarBind var;
+
+ //Debug message
+ TRACE_INFO("Parsing GetBulkRequest-PDU...\r\n");
+
+ //Make sure the SNMP version identifier is valid
+ if(context->request.version == SNMP_VERSION_1)
+ {
+ //The SNMP version is not acceptable
+ return ERROR_INVALID_TYPE;
+ }
+
+ //Enforce access policy
+ if(context->user->mode != SNMP_ACCESS_READ_ONLY &&
+ context->user->mode != SNMP_ACCESS_READ_WRITE)
+ {
+ //Total number of SNMP messages delivered to the SNMP protocol entity
+ //which represented an SNMP operation which was not allowed by the SNMP
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInBadCommunityUses, 1);
+
+ //Report an error
+ return ERROR_ACCESS_DENIED;
+ }
+
+ //Initialize response message
+ error = snmpInitResponse(context);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Point to the first variable binding of the request
+ p = context->request.varBindList;
+ length = context->request.varBindListLen;
+
+ //Lock access to MIB bases
+ snmpLockMib(context);
+
+ //Loop through the list
+ for(index = 1; length > 0; index++)
+ {
+ //The non-repeaters field specifies the number of non-repeating objects
+ //at the start of the variable binding list
+ if((index - 1) == context->request.nonRepeaters)
+ {
+ //Pointer to the first variable binding that will be processed during
+ //the next iteration
+ next = context->response.varBindList + context->response.varBindListLen;
+
+ //Actual size of the variable binding list
+ m = context->response.varBindListLen;
+
+ //This flag tells whether all variable bindings have the value field
+ //set to endOfMibView for a given iteration
+ endOfMibView = TRUE;
+
+ //If the max-repetitions field is zero, the list is trimmed to the
+ //first non-repeating variable bindings
+ if(context->request.maxRepetitions == 0)
+ break;
+ }
+
+ //Parse variable binding
+ error = snmpParseVarBinding(p, length, &var, &n);
+ //Failed to parse variable binding?
+ if(error)
+ break;
+
+ //Make sure that the object identifier is valid
+ error = oidCheck(var.oid, var.oidLen);
+ //Invalid object identifier?
+ if(error)
+ break;
+
+ //Search the MIB for the next object
+ error = snmpGetNextObject(context, &var);
+
+ //Check status code
+ if(error == NO_ERROR)
+ {
+ //Next object found
+ endOfMibView = FALSE;
+ //Retrieve object value
+ error = snmpGetObjectValue(context, &var);
+ }
+ else if(error == ERROR_OBJECT_NOT_FOUND)
+ {
+ //The variable binding's value field is set to endOfMibView
+ var.objClass = ASN1_CLASS_CONTEXT_SPECIFIC;
+ var.objType = SNMP_EXCEPTION_END_OF_MIB_VIEW;
+ var.valueLen = 0;
+
+ //Catch exception
+ error = NO_ERROR;
+ }
+ else
+ {
+ //Stop immediately
+ break;
+ }
+
+ //Failed to retrieve object value?
+ if(error)
+ {
+ //Catch exception
+ if(error == ERROR_ACCESS_DENIED ||
+ error == ERROR_OBJECT_NOT_FOUND)
+ {
+ //The variable binding's value field is set to noSuchObject
+ var.objClass = ASN1_CLASS_CONTEXT_SPECIFIC;
+ var.objType = SNMP_EXCEPTION_NO_SUCH_OBJECT;
+ var.valueLen = 0;
+ }
+ else if(error == ERROR_INSTANCE_NOT_FOUND)
+ {
+ //The variable binding's value field is set to noSuchInstance
+ var.objClass = ASN1_CLASS_CONTEXT_SPECIFIC;
+ var.objType = SNMP_EXCEPTION_NO_SUCH_INSTANCE;
+ var.valueLen = 0;
+ }
+ else
+ {
+ //Stop immediately
+ break;
+ }
+ }
+ else
+ {
+ //Total number of MIB objects which have been retrieved successfully
+ //by the SNMP protocol entity as the result of receiving valid SNMP
+ //Get-Request and Get-NextRequest PDUs
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInTotalReqVars, 1);
+ }
+
+ //Append variable binding to the list
+ error = snmpWriteVarBinding(context, &var);
+ //Any error to report?
+ if(error)
+ break;
+
+ //Advance data pointer
+ p += n;
+ length -= n;
+
+ //Next iteration?
+ if(length == 0 && index > context->request.nonRepeaters)
+ {
+ //Decrement repeat counter
+ context->request.maxRepetitions--;
+
+ //Last iteration?
+ if(!context->request.maxRepetitions)
+ break;
+ //All variable bindings have the value field set to endOfMibView?
+ if(endOfMibView)
+ break;
+
+ //Point to the first variable binding to be processed
+ p = next;
+ //Number of bytes to be processed
+ length = context->response.varBindListLen - m;
+ //Rewind index
+ index = context->request.nonRepeaters;
+ }
+ }
+
+ //Unlock access to MIB bases
+ snmpUnlockMib(context);
+
+ //Check status code
+ if(error == ERROR_BUFFER_OVERFLOW)
+ {
+ //If the size of the message containing the requested number of variable
+ //bindings would be greater than the maximum message size, then the
+ //response is generated with a lesser number of variable bindings
+ }
+ else if(error)
+ {
+ //Set error-status and error-index fields
+ error = snmpTranslateStatusCode(&context->response, error, index);
+ //If the parsing of the request fails, the SNMP agent discards the message
+ if(error)
+ return error;
+
+ //The Response-PDU is re-formatted with the same values in its request-id
+ //and variable-bindings fields as the received GetRequest-PDU
+ error = snmpCopyVarBindingList(context);
+ //Any error to report?
+ if(error)
+ return error;
+ }
+
+ //Successful processing
+ return NO_ERROR;
+#else
+ //Not implemented
+ return ERROR_NOT_IMPLEMENTED;
+#endif
+}
+
+
+/**
+ * @brief Process SetRequest-PDU
+ * @param[in] context Pointer to the SNMP agent context
+ * @return Error code
+ **/
+
+error_t snmpProcessSetRequestPdu(SnmpAgentContext *context)
+{
+ error_t error;
+ int_t index;
+ size_t n;
+ size_t length;
+ const uint8_t *p;
+ SnmpVarBind var;
+
+ //Debug message
+ TRACE_INFO("Parsing SetRequest-PDU...\r\n");
+
+ //Total number of SNMP Set-Request PDUs which have been accepted and
+ //processed by the SNMP protocol entity
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInSetRequests, 1);
+
+ //Enforce access policy
+ if(context->user->mode != SNMP_ACCESS_WRITE_ONLY &&
+ context->user->mode != SNMP_ACCESS_READ_WRITE)
+ {
+ //Total number of SNMP messages delivered to the SNMP protocol entity
+ //which represented an SNMP operation which was not allowed by the SNMP
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInBadCommunityUses, 1);
+
+ //Report an error
+ return ERROR_ACCESS_DENIED;
+ }
+
+ //Initialize response message
+ error = snmpInitResponse(context);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //The variable bindings are processed as a two phase operation. In the
+ //first phase, each variable binding is validated
+ p = context->request.varBindList;
+ length = context->request.varBindListLen;
+
+ //Loop through the list
+ for(index = 1; length > 0; index++)
+ {
+ //Parse variable binding
+ error = snmpParseVarBinding(p, length, &var, &n);
+ //Failed to parse variable binding?
+ if(error)
+ break;
+
+ //Assign object value
+ error = snmpSetObjectValue(context, &var, FALSE);
+ //Any error to report?
+ if(error)
+ break;
+
+ //Advance data pointer
+ p += n;
+ length -= n;
+ }
+
+ //If all validations are successful, then each variable is altered in
+ //the second phase
+ if(!error)
+ {
+ //The changes are committed to the MIB base during the second phase
+ p = context->request.varBindList;
+ length = context->request.varBindListLen;
+
+ //Lock access to MIB bases
+ snmpLockMib(context);
+
+ //Loop through the list
+ for(index = 1; length > 0; index++)
+ {
+ //Parse variable binding
+ error = snmpParseVarBinding(p, length, &var, &n);
+ //Failed to parse variable binding?
+ if(error)
+ break;
+
+ //Assign object value
+ error = snmpSetObjectValue(context, &var, TRUE);
+ //Any error to report?
+ if(error)
+ break;
+
+ //Total number of MIB objects which have been altered successfully
+ //by the SNMP protocol entity as the result of receiving valid
+ //SNMP Set-Request PDUs
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpInTotalSetVars, 1);
+
+ //Advance data pointer
+ p += n;
+ length -= n;
+ }
+
+ //Unlock access to MIB bases
+ snmpUnlockMib(context);
+ }
+
+ //Any error to report?
+ if(error)
+ {
+ //Set error-status and error-index fields
+ error = snmpTranslateStatusCode(&context->response, error, index);
+ //If the parsing of the request fails, the SNMP agent discards the message
+ if(error)
+ return error;
+ }
+
+ //The SNMP agent sends back a GetResponse-PDU of identical form
+ error = snmpCopyVarBindingList(context);
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Format Trap-PDU or SNMPv2-Trap-PDU
+ * @param[in] context Pointer to the SNMP agent context
+ * @param[in] version SNMP version identifier
+ * @param[in] username User name or community name
+ * @param[in] genericTrapType Generic trap type
+ * @param[in] specificTrapCode Specific code
+ * @param[in] objectList List of object names
+ * @param[in] objectListSize Number of entries in the list
+ * @return Error code
+ **/
+
+error_t snmpFormatTrapPdu(SnmpAgentContext *context, SnmpVersion version,
+ const char_t *username, uint_t genericTrapType, uint_t specificTrapCode,
+ const SnmpTrapObject *objectList, uint_t objectListSize)
+{
+ error_t error;
+ uint_t i;
+ size_t n;
+ systime_t time;
+ SnmpMessage *message;
+ SnmpVarBind var;
+
+ //Point to the SNMP message
+ message = &context->response;
+ //Initialize SNMP message
+ snmpInitMessage(message);
+
+ //SNMP version identifier
+ message->version = version;
+
+#if (SNMP_V1_SUPPORT == ENABLED)
+ //SNMPv1 version?
+ if(version == SNMP_VERSION_1)
+ {
+#if (IPV4_SUPPORT == ENABLED)
+ NetInterface *interface;
+
+ //Point to the underlying network interface
+ interface = context->settings.interface;
+#endif
+
+ //Community name
+ message->community = username;
+ message->communityLen = strlen(username);
+
+ //Prepare to send a Trap-PDU
+ message->pduType = SNMP_PDU_TRAP;
+ //Type of object generating trap
+ message->enterpriseOid = context->enterpriseOid;
+ message->enterpriseOidLen = context->enterpriseOidLen;
+
+#if (IPV4_SUPPORT == ENABLED)
+ //Address of object generating trap
+ if(interface != NULL)
+ message->agentAddr = interface->ipv4Context.addr;
+#endif
+
+ //Generic trap type
+ message->genericTrapType = genericTrapType;
+ //Specific trap code
+ message->specificTrapCode = specificTrapCode;
+ //Timestamp
+ message->timestamp = osGetSystemTime() / 10;
+ }
+ else
+#endif
+#if (SNMP_V2C_SUPPORT == ENABLED)
+ //SNMPv2c version?
+ if(version == SNMP_VERSION_2C)
+ {
+ //Community name
+ message->community = username;
+ message->communityLen = strlen(username);
+
+ //Prepare to send a SNMPv2-Trap-PDU
+ message->pduType = SNMP_PDU_TRAP_V2;
+ }
+ else
+#endif
+#if (SNMP_V3_SUPPORT == ENABLED)
+ //SNMPv3 version?
+ if(version == SNMP_VERSION_3)
+ {
+ //Maximum message size supported by the sender
+ message->msgMaxSize = SNMP_MAX_MSG_SIZE;
+
+ //Bit fields which control processing of the message
+ if(context->user->authProtocol != SNMP_AUTH_PROTOCOL_NONE)
+ message->msgFlags |= SNMP_MSG_FLAG_AUTH;
+ if(context->user->privProtocol != SNMP_PRIV_PROTOCOL_NONE)
+ message->msgFlags |= SNMP_MSG_FLAG_PRIV;
+
+ //Security model used by the sender
+ message->msgSecurityModel = SNMP_SECURITY_MODEL_USM;
+
+ //Authoritative engine identifier
+ message->msgAuthEngineId = context->contextEngine;
+ message->msgAuthEngineIdLen = context->contextEngineLen;
+ //Number of times the SNMP engine has rebooted
+ message->msgAuthEngineBoots = context->engineBoots;
+ //Number of seconds since last reboot
+ message->msgAuthEngineTime = context->engineTime;
+ //User name
+ message->msgUserName = username;
+ message->msgUserNameLen = strlen(username);
+ //Authentication parameters
+ message->msgAuthParameters = NULL;
+
+ //Length of the authentication parameters
+ if(context->user->authProtocol == SNMP_AUTH_PROTOCOL_MD5)
+ message->msgAuthParametersLen = 12;
+ else if(context->user->authProtocol == SNMP_AUTH_PROTOCOL_SHA1)
+ message->msgAuthParametersLen = 12;
+ else if(context->user->authProtocol == SNMP_AUTH_PROTOCOL_SHA224)
+ message->msgAuthParametersLen = 16;
+ else if(context->user->authProtocol == SNMP_AUTH_PROTOCOL_SHA256)
+ message->msgAuthParametersLen = 24;
+ else if(context->user->authProtocol == SNMP_AUTH_PROTOCOL_SHA384)
+ message->msgAuthParametersLen = 32;
+ else if(context->user->authProtocol == SNMP_AUTH_PROTOCOL_SHA512)
+ message->msgAuthParametersLen = 48;
+ else
+ message->msgAuthParametersLen = 0;
+
+ //Privacy parameters
+ message->msgPrivParameters = context->privParameters;
+
+ //Length of the privacy parameters
+ if(context->user->privProtocol == SNMP_PRIV_PROTOCOL_DES)
+ message->msgPrivParametersLen = 8;
+ else if(context->user->privProtocol == SNMP_PRIV_PROTOCOL_AES)
+ message->msgPrivParametersLen = 8;
+ else
+ message->msgPrivParametersLen = 0;
+
+ //Context engine identifier
+ message->contextEngineId = context->contextEngine;
+ message->contextEngineIdLen = context->contextEngineLen;
+ //Context name
+ message->contextName = (uint8_t *) context->contextName;
+ message->contextNameLen = strlen(context->contextName);
+
+ //Prepare to send a SNMPv2-Trap-PDU
+ message->pduType = SNMP_PDU_TRAP_V2;
+ }
+ else
+#endif
+ //Invalid SNMP version?
+ {
+ //Report an error
+ return ERROR_INVALID_VERSION;
+ }
+
+ //Make room for the message header at the beginning of the buffer
+ error = snmpComputeMessageOverhead(&context->response);
+ //Any error to report?
+ if(error)
+ return error;
+
+#if (SNMP_V2C_SUPPORT == ENABLED || SNMP_V3_SUPPORT == ENABLED)
+ //SNMPv2c or SNMPv3 version?
+ if(version == SNMP_VERSION_2C || version == SNMP_VERSION_3)
+ {
+ //Get current time
+ time = osGetSystemTime() / 10;
+
+ //Encode the object value using ASN.1 rules
+ error = snmpEncodeUnsignedInt32(time, message->buffer, &n);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //The first two variable bindings in the variable binding list of an
+ //SNMPv2-Trap-PDU are sysUpTime.0 and snmpTrapOID.0 respectively
+ var.oid = sysUpTimeObject;
+ var.oidLen = sizeof(sysUpTimeObject);
+ var.objClass = ASN1_CLASS_APPLICATION;
+ var.objType = MIB_TYPE_TIME_TICKS;
+ var.value = message->buffer;
+ var.valueLen = n;
+
+ //Append sysUpTime.0 to the variable binding list
+ error = snmpWriteVarBinding(context, &var);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Generic or enterprise-specific trap?
+ if(genericTrapType < SNMP_TRAP_ENTERPRISE_SPECIFIC)
+ {
+ //Retrieve the length of the snmpTraps OID
+ n = sizeof(snmpTrapsObject);
+ //Copy the OID
+ memcpy(message->buffer, snmpTrapsObject, n);
+
+ //For generic traps, the SNMPv2 snmpTrapOID parameter shall be
+ //the corresponding trap as defined in section 2 of 3418
+ message->buffer[n] = genericTrapType + 1;
+
+ //Update the length of the snmpTrapOID parameter
+ n++;
+ }
+ else
+ {
+ //Retrieve the length of the enterprise OID
+ n = context->enterpriseOidLen;
+
+ //For enterprise specific traps, the SNMPv2 snmpTrapOID parameter shall
+ //be the concatenation of the SNMPv1 enterprise OID and two additional
+ //sub-identifiers: '0' and the SNMPv1 specific trap parameter
+ memcpy(message->buffer, context->enterpriseOid, n);
+
+ //Concatenate the '0' sub-identifier
+ message->buffer[n++] = 0;
+
+ //Concatenate the specific trap parameter
+ message->buffer[n] = specificTrapCode % 128;
+
+ //Loop as long as necessary
+ for(i = 1; specificTrapCode > 128; i++)
+ {
+ //Split the binary representation into 7 bit chunks
+ specificTrapCode /= 128;
+ //Make room for the new chunk
+ memmove(message->buffer + n + 1, message->buffer + n, i);
+ //Set the most significant bit in the current chunk
+ message->buffer[n] = OID_MORE_FLAG | (specificTrapCode % 128);
+ }
+
+ //Update the length of the snmpTrapOID parameter
+ n += i;
+ }
+
+ //The snmpTrapOID.0 variable occurs as the second variable
+ //binding in every SNMPv2-Trap-PDU
+ var.oid = snmpTrapOidObject;
+ var.oidLen = sizeof(snmpTrapOidObject);
+ var.objClass = ASN1_CLASS_UNIVERSAL;
+ var.objType = ASN1_TYPE_OBJECT_IDENTIFIER;
+ var.value = message->buffer;
+ var.valueLen = n;
+
+ //Append snmpTrapOID.0 to the variable binding list
+ error = snmpWriteVarBinding(context, &var);
+ //Any error to report?
+ if(error)
+ return error;
+ }
+#endif
+
+ //Loop through the list of objects
+ for(i = 0; i < objectListSize; i++)
+ {
+ //Get object identifier
+ var.oid = objectList[i].oid;
+ var.oidLen = objectList[i].oidLen;
+
+ //Retrieve object value
+ error = snmpGetObjectValue(context, &var);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Append variable binding to the list
+ error = snmpWriteVarBinding(context, &var);
+ //Any error to report?
+ if(error)
+ return error;
+ }
+
+ //Total number of SNMP Trap PDUs which have been generated by
+ //the SNMP protocol entity
+ MIB2_INC_COUNTER32(mib2Base.snmpGroup.snmpOutTraps, 1);
+
+ //Format PDU header
+ error = snmpWritePduHeader(&context->response);
+ //Return status code
+ return error;
+}
+
+
+/**
+ * @brief Format Report-PDU
+ * @param[in] context Pointer to the SNMP agent context
+ * @param[in] errorIndication Error indication
+ * @return Error code
+ **/
+
+error_t snmpFormatReportPdu(SnmpAgentContext *context, error_t errorIndication)
+{
+ error_t error;
+
+#if (SNMP_V3_SUPPORT == ENABLED)
+ size_t n;
+ SnmpVarBind var;
+
+ //Initialize SNMP message
+ snmpInitMessage(&context->response);
+
+ //SNMP version identifier
+ context->response.version = context->request.version;
+
+ //Message identifier
+ context->response.msgId = context->request.msgId;
+ //Maximum message size supported by the sender
+ context->response.msgMaxSize = SNMP_MAX_MSG_SIZE;
+ //Bit fields which control processing of the message
+ context->response.msgFlags = 0;
+ //Security model used by the sender
+ context->response.msgSecurityModel = SNMP_SECURITY_MODEL_USM;
+
+ //Authoritative engine identifier
+ context->response.msgAuthEngineId = context->contextEngine;
+ context->response.msgAuthEngineIdLen = context->contextEngineLen;
+ //Number of times the SNMP engine has rebooted
+ context->response.msgAuthEngineBoots = context->engineBoots;
+ //Number of seconds since last reboot
+ context->response.msgAuthEngineTime = context->engineTime;
+
+ //Context engine identifier
+ context->response.contextEngineId = context->contextEngine;
+ context->response.contextEngineIdLen = context->contextEngineLen;
+ //Context name
+ context->response.contextName = (uint8_t *) context->contextName;
+ context->response.contextNameLen = strlen(context->contextName);
+
+ //PDU type
+ context->response.pduType = SNMP_PDU_REPORT;
+ //Request identifier
+ context->response.requestId = context->request.requestId;
+
+ //Make room for the message header at the beginning of the buffer
+ error = snmpComputeMessageOverhead(&context->response);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Encode the object value using ASN.1 rules
+ error = snmpEncodeUnsignedInt32(1, context->response.buffer, &n);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Check error indication
+ switch(errorIndication)
+ {
+ case ERROR_UNSUPPORTED_SECURITY_LEVEL:
+ //Add the usmStatsUnsupportedSecLevels counter in the varBindList
+ var.oid = usmStatsUnsupportedSecLevelsObject;
+ var.oidLen = sizeof(usmStatsUnsupportedSecLevelsObject);
+ break;
+ case ERROR_NOT_IN_TIME_WINDOW:
+ //Add the usmStatsNotInTimeWindows counter in the varBindList
+ var.oid = usmStatsNotInTimeWindowsObject;
+ var.oidLen = sizeof(usmStatsNotInTimeWindowsObject);
+ break;
+ case ERROR_UNKNOWN_USER_NAME:
+ //Add the usmStatsUnknownUserNames counter in the varBindList
+ var.oid = usmStatsUnknownUserNamesObject;
+ var.oidLen = sizeof(usmStatsUnknownUserNamesObject);
+ break;
+ case ERROR_UNKNOWN_ENGINE_ID:
+ //Add the usmStatsUnknownEngineIDs counter in the varBindList
+ var.oid = usmStatsUnknownEngineIdsObject;
+ var.oidLen = sizeof(usmStatsUnknownEngineIdsObject);
+ break;
+ case ERROR_AUTHENTICATION_FAILED:
+ //Add the usmStatsWrongDigests counter in the varBindList
+ var.oid = usmStatsWrongDigestsObject;
+ var.oidLen = sizeof(usmStatsWrongDigestsObject);
+ break;
+ case ERROR_DECRYPTION_FAILED:
+ //Add the usmStatsDecryptionErrors counter in the varBindList
+ var.oid = usmStatsDecryptionErrorsObject;
+ var.oidLen = sizeof(usmStatsDecryptionErrorsObject);
+ break;
+ default:
+ //Just for sanity's sake...
+ var.oid = NULL;
+ var.oidLen = 0;
+ break;
+ }
+
+ //The counter is encoded in ASN.1 format
+ var.objClass = ASN1_CLASS_APPLICATION;
+ var.objType = MIB_TYPE_COUNTER32;
+ var.value = context->response.buffer;
+ var.valueLen = n;
+
+ //Append the variable binding list to the varBindList
+ error = snmpWriteVarBinding(context, &var);
+ //Any error to report?
+ if(error)
+ return error;
+
+ //Format PDU header
+ error = snmpWritePduHeader(&context->response);
+#else
+ //SNMPv3 is not supported
+ error = ERROR_NOT_IMPLEMENTED;
+#endif
+
+ //Return status code
+ return error;
+}
+
+#endif
+