datapath-windows/ovsext/Netlink.h

   1 /*
   2  * Copyright (c) 2008, 2009, 2010, 2011, 2013, 2014 Nicira, Inc.
   3  *
   4  * Licensed under the Apache License, Version 2.0 (the "License");
   5  * you may not use this file except in compliance with the License.
   6  * You may obtain a copy of the License at:
   7  *
   8  *     http://www.apache.org/licenses/LICENSE-2.0
   9  *
  10  * Unless required by applicable law or agreed to in writing, software
  11  * distributed under the License is distributed on an "AS IS" BASIS,
  12  * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
  13  * See the License for the specific language governing permissions and
  14  * limitations under the License.
  15  */
  16
  17 #ifndef __NETLINK_H_
  18 #define __NETLINK_H_ 1
  19
  20 #include "OvsTypes.h"
  21 #include "NetlinkProto.h"
  22
  23 /* Netlink attribute types. */
  24 typedef enum
  25 {
  26     NL_A_NO_ATTR = 0,
  27     NL_A_UNSPEC,
  28     NL_A_U8,
  29     NL_A_U16,
  30     NL_A_BE16 = NL_A_U16,
  31     NL_A_U32,
  32     NL_A_BE32 = NL_A_U32,
  33     NL_A_U64,
  34     NL_A_BE64 = NL_A_U64,
  35     NL_A_STRING,
  36     NL_A_FLAG,
  37     NL_A_NESTED,
  38     N_NL_ATTR_TYPES
  39 } NL_ATTR_TYPE;
  40
  41 /* Netlink attribute policy.
  42  * Specifies the policy for parsing for netlink attribute. */
  43 typedef struct _NL_POLICY
  44 {
  45     NL_ATTR_TYPE type;
  46     UINT32 minLen;
  47     UINT32 maxLen;
  48 } NL_POLICY, *PNL_POLICY;
  49
  50 /* This macro is careful to check for attributes with bad lengths. */
  51 #define NL_ATTR_FOR_EACH(ITER, LEFT, ATTRS, ATTRS_LEN)                  \
  52     for ((ITER) = (ATTRS), (LEFT) = (ATTRS_LEN);                        \
  53          NlAttrIsValid(ITER, LEFT);                                     \
  54          (LEFT) -= NlAttrLenPad(ITER, LEFT), (ITER) = NlAttrNext(ITER))
  55
  56 /* This macro does not check for attributes with bad lengths.  It should only
  57  * be used with messages from trusted sources or with messages that have
  58  * already been validated (e.g. with NL_ATTR_FOR_EACH).  */
  59 #define NL_ATTR_FOR_EACH_UNSAFE(ITER, LEFT, ATTRS, ATTRS_LEN)           \
  60     for ((ITER) = (ATTRS), (LEFT) = (ATTRS_LEN);                        \
  61          (LEFT) > 0;                                                    \
  62          (LEFT) -= NLA_ALIGN((ITER)->nlaLen), (ITER) = NlAttrNext(ITER))
  63
  64 #define NL_ATTR_GET_AS(NLA, TYPE) \
  65         (*(TYPE*) NlAttrGetUnspec(nla, sizeof(TYPE)))
  66
  67 /* Netlink message accessing the payload */
  68 PVOID NlMsgAt(const PNL_MSG_HDR nlh, UINT32 offset);
  69 UINT32 NlMsgSize(const PNL_MSG_HDR nlh);
  70 PCHAR NlMsgPayload(const PNL_MSG_HDR nlh);
  71 UINT32 NlMsgPayloadLen(const PNL_MSG_HDR nlh);
  72 PNL_ATTR NlMsgAttrs(const PNL_MSG_HDR nlh);
  73 INT NlMsgAttrLen(const PNL_MSG_HDR nlh);
  74
  75 /* Netlink message parse */
  76 PNL_MSG_HDR NlMsgNext(const PNL_MSG_HDR nlh);
  77 INT NlAttrIsValid(const PNL_ATTR nla, UINT32 maxlen);
  78 UINT32 NlAttrLenPad(const PNL_ATTR nla, UINT32 maxlen);
  79
  80 /* Netlink attribute parsing. */
  81 UINT32 NlAttrMinLen(NL_ATTR_TYPE type);
  82 UINT32 NlAttrMinLen(NL_ATTR_TYPE type);
  83 PNL_ATTR NlAttrNext(const PNL_ATTR nla);
  84 UINT16 NlAttrType(const PNL_ATTR nla);
  85 PVOID NlAttrData(const PNL_ATTR nla);
  86 UINT32 NlAttrGetSize(const PNL_ATTR nla);
  87 const PVOID NlAttrGet(const PNL_ATTR nla);
  88 const PVOID NlAttrGetUnspec(const PNL_ATTR nla, UINT32 size);
  89 BE64 NlAttrGetBe64(const PNL_ATTR nla);
  90 BE32 NlAttrGetBe32(const PNL_ATTR nla);
  91 UINT8 NlAttrGetU8(const PNL_ATTR nla);
  92 UINT32 NlAttrGetU32(const PNL_ATTR nla);
  93 const PNL_ATTR NlAttrFind__(const PNL_ATTR attrs,
  94                             UINT32 size, UINT16 type);
  95 const PNL_ATTR NlAttrFindNested(const PNL_ATTR nla,
  96                                 UINT16 type);
  97 BOOLEAN NlAttrParse(const PNL_MSG_HDR nlMsg, UINT32 attrOffset,
  98                     const NL_POLICY policy[],
  99                     PNL_ATTR attrs[], UINT32 n_attrs);
 100
 101 /* Netlink attribute validation */
 102 BOOLEAN NlAttrValidate(const PNL_ATTR, const PNL_POLICY);
 103
 104 #endif /* __NETLINK_H_ */