inetmib1: Use a helper function to get the item and instance of the MIB2 IP address table.

This commit is contained in:
Juan Lang 2008-06-25 09:30:59 -07:00 committed by Alexandre Julliard
parent 969bc943ac
commit 297190fde2
1 changed files with 124 additions and 86 deletions

View File

@ -311,6 +311,126 @@ static AsnInteger32 getItemFromOid(AsnObjectIdentifier *oid,
return ret;
}
struct GenericTable
{
DWORD numEntries;
BYTE entries[1];
};
/* Finds the index in table whose IP address (at offset addressOffset within the
* entry) matches that given the OID, which is assumed to have at least 4 IDs.
*/
static UINT findOIDIPAddressInTable(AsnObjectIdentifier *oid,
struct GenericTable *table, size_t tableEntrySize, size_t addressOffset)
{
DWORD addr;
UINT i, index = 0;
/* Map the IDs to an IP address in little-endian order */
addr = (BYTE)oid->ids[3] << 24 | (BYTE)oid->ids[2] << 16 |
(BYTE)oid->ids[1] << 8 | (BYTE)oid->ids[0];
/* Find the item whose address matches */
for (i = 0; !index && i < table->numEntries; i++)
{
DWORD tableAddr =
*(DWORD *)(table->entries + i * tableEntrySize + addressOffset);
if (addr == tableAddr)
index = i + 1;
}
return index;
}
/* Given an OID and a base OID that it must begin with, finds the item and
* element of the table whose IP address matches the instance from the OID.
* E.g., given an OID foo.1.2.3.4.5 and a base OID foo, returns item 1 and the
* index of the entry in the table whose IP address is 2.3.4.5.
* If bPduType is not SNMP_PDU_GETNEXT and either the item or instance is
* missing, returns SNMP_ERRORSTATUS_NOSUCHNAME.
* If bPduType is SNMP_PDU_GETNEXT, returns the successor to the item and
* instance, or item 1, instance 1 if either is missing.
*/
static AsnInteger32 getItemAndIpAddressInstanceFromOid(AsnObjectIdentifier *oid,
AsnObjectIdentifier *base, BYTE bPduType, struct GenericTable *table,
size_t tableEntrySize, size_t addressOffset, UINT *item, UINT *instance)
{
AsnInteger32 ret = SNMP_ERRORSTATUS_NOERROR;
if (!table)
return SNMP_ERRORSTATUS_NOSUCHNAME;
switch (bPduType)
{
case SNMP_PDU_GETNEXT:
if (SnmpUtilOidNCmp(oid, base, base->idLength) < 0)
{
/* Return the first item and instance from the table */
*item = 1;
*instance = 1;
}
else if (!SnmpUtilOidNCmp(oid, base, base->idLength) &&
oid->idLength < base->idLength + 5)
{
/* Either the table or an item is specified, but the instance is
* not.
*/
*instance = 1;
if (oid->idLength >= base->idLength + 1)
{
*item = oid->ids[base->idLength];
if (!*item)
*item = 1;
}
else
*item = 1;
}
else if (!SnmpUtilOidNCmp(oid, base, base->idLength) &&
oid->idLength == base->idLength + 5)
{
*item = oid->ids[base->idLength];
if (!*item)
{
*instance = 1;
*item = 1;
}
else
{
AsnObjectIdentifier ipOid = { 4, oid->ids + base->idLength + 1
};
*instance = findOIDIPAddressInTable(&ipOid, table,
tableEntrySize, addressOffset) + 1;
if (*instance > table->numEntries)
ret = SNMP_ERRORSTATUS_NOSUCHNAME;
}
}
else
ret = SNMP_ERRORSTATUS_NOSUCHNAME;
break;
default:
if (!SnmpUtilOidNCmp(oid, base, base->idLength) &&
oid->idLength == base->idLength + 5)
{
*item = oid->ids[base->idLength];
if (!*item)
ret = SNMP_ERRORSTATUS_NOSUCHNAME;
else
{
AsnObjectIdentifier ipOid = { 4, oid->ids + base->idLength + 1
};
*instance = findOIDIPAddressInTable(&ipOid, table,
tableEntrySize, addressOffset);
if (!*instance)
ret = SNMP_ERRORSTATUS_NOSUCHNAME;
}
}
else
ret = SNMP_ERRORSTATUS_NOSUCHNAME;
}
return ret;
}
static struct structToAsnValue mib2IfEntryMap[] = {
{ FIELD_OFFSET(MIB_IFROW, dwIndex), copyInt },
{ FIELD_OFFSET(MIB_IFROW, dwDescrLen), copyLengthPrecededString },
@ -516,92 +636,10 @@ static BOOL mib2IpAddrQuery(BYTE bPduType, SnmpVarBind *pVarBind,
{
case SNMP_PDU_GET:
case SNMP_PDU_GETNEXT:
*pErrorStatus = 0;
if (!ipAddrTable)
{
/* There is no address present, so let the caller deal with
* finding the successor.
*/
*pErrorStatus = SNMP_ERRORSTATUS_NOSUCHNAME;
}
else if (!SnmpUtilOidNCmp(&pVarBind->name, &myOid, myOid.idLength) &&
pVarBind->name.idLength < myOid.idLength + 5)
{
/* Either the table or an element within the table is specified,
* but the instance is not.
*/
if (bPduType == SNMP_PDU_GET)
{
/* Can't get an interface entry without specifying the
* instance.
*/
*pErrorStatus = SNMP_ERRORSTATUS_NOSUCHNAME;
}
else
{
/* Get the first address */
tableIndex = 1;
if (pVarBind->name.idLength == myOid.idLength + 1)
item = pVarBind->name.ids[myOid.idLength];
else
item = 1;
}
}
else if (!SnmpUtilOidNCmp(&pVarBind->name, &myOid, myOid.idLength) &&
pVarBind->name.idLength == myOid.idLength + 5)
{
item = pVarBind->name.ids[myOid.idLength];
if (!item)
{
if (bPduType == SNMP_PDU_GET)
*pErrorStatus = SNMP_ERRORSTATUS_NOSUCHNAME;
else
{
tableIndex = 1;
item = 1;
}
}
else if (item - 1 >= DEFINE_SIZEOF(mib2IpAddrMap))
*pErrorStatus = SNMP_ERRORSTATUS_NOSUCHNAME;
else
{
DWORD addr;
UINT i;
/* Map the IDs to an IP address in little-endian order */
addr =
(BYTE)pVarBind->name.ids[myOid.idLength + 4] << 24 |
(BYTE)pVarBind->name.ids[myOid.idLength + 3] << 16 |
(BYTE)pVarBind->name.ids[myOid.idLength + 2] << 8 |
(BYTE)pVarBind->name.ids[myOid.idLength + 1];
/* Find the item whose address matches */
for (i = 0; !tableIndex && i < ipAddrTable->dwNumEntries; i++)
if (addr == ipAddrTable->table[i].dwAddr)
tableIndex = i + 1;
if (bPduType == SNMP_PDU_GETNEXT)
{
if (!tableIndex)
{
/* No address matched, so let caller find successor */
*pErrorStatus = SNMP_ERRORSTATUS_NOSUCHNAME;
}
else
{
/* We want the successor to the matching address */
tableIndex++;
}
}
if (tableIndex > ipAddrTable->dwNumEntries)
*pErrorStatus = SNMP_ERRORSTATUS_NOSUCHNAME;
}
}
else
{
/* Some item after the address table was requested, so let the
* caller deal with finding a successor.
*/
*pErrorStatus = SNMP_ERRORSTATUS_NOSUCHNAME;
}
*pErrorStatus = getItemAndIpAddressInstanceFromOid(&pVarBind->name,
&myOid, bPduType, (struct GenericTable *)ipAddrTable,
sizeof(MIB_IPADDRROW), FIELD_OFFSET(MIB_IPADDRROW, dwAddr), &item,
&tableIndex);
if (!*pErrorStatus)
{
assert(tableIndex);