blob: 6d57048b3947bf5c583fc9d7d5c7180797a51589 [file] [log] [blame]
// Copyright (c) 2012 The Chromium OS Authors. All rights reserved.
// Use of this source code is governed by a BSD-style license that can be
// found in the LICENSE file.
#include "shill/rtnl_message.h"
#include <base/logging.h>
#include <sys/socket.h>
#include <linux/netlink.h>
#include <linux/rtnetlink.h>
namespace shill {
struct RTNLHeader {
RTNLHeader() {
memset(this, 0, sizeof(*this));
}
struct nlmsghdr hdr;
union {
struct ifinfomsg ifi;
struct ifaddrmsg ifa;
struct rtmsg rtm;
struct rtgenmsg gen;
};
};
RTNLMessage::RTNLMessage()
: type_(kTypeUnknown),
mode_(kModeUnknown),
flags_(0),
seq_(0),
pid_(0),
interface_index_(0),
family_(IPAddress::kFamilyUnknown) {}
RTNLMessage::RTNLMessage(Type type,
Mode mode,
unsigned int flags,
uint32 seq,
uint32 pid,
int interface_index,
IPAddress::Family family)
: type_(type),
mode_(mode),
flags_(flags),
seq_(seq),
pid_(pid),
interface_index_(interface_index),
family_(family) {}
bool RTNLMessage::Decode(const ByteString &msg) {
bool ret = DecodeInternal(msg);
if (!ret) {
Reset();
}
return ret;
}
bool RTNLMessage::DecodeInternal(const ByteString &msg) {
const RTNLHeader *hdr =
reinterpret_cast<const RTNLHeader *>(msg.GetConstData());
if (msg.GetLength() < sizeof(hdr->hdr) ||
msg.GetLength() < hdr->hdr.nlmsg_len)
return false;
Mode mode = kModeUnknown;
switch (hdr->hdr.nlmsg_type) {
case RTM_NEWLINK:
case RTM_NEWADDR:
case RTM_NEWROUTE:
mode = kModeAdd;
break;
case RTM_DELLINK:
case RTM_DELADDR:
case RTM_DELROUTE:
mode = kModeDelete;
break;
default:
return false;
}
rtattr *attr_data = NULL;
int attr_length = 0;
switch (hdr->hdr.nlmsg_type) {
case RTM_NEWLINK:
case RTM_DELLINK:
if (!DecodeLink(hdr, mode, &attr_data, &attr_length))
return false;
break;
case RTM_NEWADDR:
case RTM_DELADDR:
if (!DecodeAddress(hdr, mode, &attr_data, &attr_length))
return false;
break;
case RTM_NEWROUTE:
case RTM_DELROUTE:
if (!DecodeRoute(hdr, mode, &attr_data, &attr_length))
return false;
break;
default:
NOTREACHED();
}
flags_ = hdr->hdr.nlmsg_flags;
seq_ = hdr->hdr.nlmsg_seq;
pid_ = hdr->hdr.nlmsg_pid;
while (attr_data && RTA_OK(attr_data, attr_length)) {
SetAttribute(
attr_data->rta_type,
ByteString(reinterpret_cast<unsigned char *>(RTA_DATA(attr_data)),
RTA_PAYLOAD(attr_data)));
attr_data = RTA_NEXT(attr_data, attr_length);
}
if (attr_length) {
// We hit a parse error while going through the attributes
attributes_.clear();
return false;
}
return true;
}
bool RTNLMessage::DecodeLink(const RTNLHeader *hdr,
Mode mode,
rtattr **attr_data,
int *attr_length) {
if (hdr->hdr.nlmsg_len < NLMSG_LENGTH(sizeof(hdr->ifi))) {
return false;
}
mode_ = mode;
*attr_data = IFLA_RTA(NLMSG_DATA(&hdr->hdr));
*attr_length = IFLA_PAYLOAD(&hdr->hdr);
type_ = kTypeLink;
family_ = hdr->ifi.ifi_family;
interface_index_ = hdr->ifi.ifi_index;
set_link_status(LinkStatus(hdr->ifi.ifi_type,
hdr->ifi.ifi_flags,
hdr->ifi.ifi_change));
return true;
}
bool RTNLMessage::DecodeAddress(const RTNLHeader *hdr,
Mode mode,
rtattr **attr_data,
int *attr_length) {
if (hdr->hdr.nlmsg_len < NLMSG_LENGTH(sizeof(hdr->ifa))) {
return false;
}
mode_ = mode;
*attr_data = IFA_RTA(NLMSG_DATA(&hdr->hdr));
*attr_length = IFA_PAYLOAD(&hdr->hdr);
type_ = kTypeAddress;
family_ = hdr->ifa.ifa_family;
interface_index_ = hdr->ifa.ifa_index;
set_address_status(AddressStatus(hdr->ifa.ifa_prefixlen,
hdr->ifa.ifa_flags,
hdr->ifa.ifa_scope));
return true;
}
bool RTNLMessage::DecodeRoute(const RTNLHeader *hdr,
Mode mode,
rtattr **attr_data,
int *attr_length) {
if (hdr->hdr.nlmsg_len < NLMSG_LENGTH(sizeof(hdr->rtm))) {
return false;
}
mode_ = mode;
*attr_data = RTM_RTA(NLMSG_DATA(&hdr->hdr));
*attr_length = RTM_PAYLOAD(&hdr->hdr);
type_ = kTypeRoute;
family_ = hdr->rtm.rtm_family;
set_route_status(RouteStatus(hdr->rtm.rtm_dst_len,
hdr->rtm.rtm_src_len,
hdr->rtm.rtm_table,
hdr->rtm.rtm_protocol,
hdr->rtm.rtm_scope,
hdr->rtm.rtm_type,
hdr->rtm.rtm_flags));
return true;
}
ByteString RTNLMessage::Encode() const {
if (type_ != kTypeLink &&
type_ != kTypeAddress &&
type_ != kTypeRoute) {
return ByteString();
}
RTNLHeader hdr;
hdr.hdr.nlmsg_flags = flags_;
hdr.hdr.nlmsg_seq = seq_;
hdr.hdr.nlmsg_pid = pid_;
if (mode_ == kModeGet) {
if (type_ == kTypeLink) {
hdr.hdr.nlmsg_type = RTM_GETLINK;
} else if (type_ == kTypeAddress) {
hdr.hdr.nlmsg_type = RTM_GETADDR;
} else if (type_ == kTypeRoute) {
hdr.hdr.nlmsg_type = RTM_GETROUTE;
} else {
NOTIMPLEMENTED();
return ByteString();
}
hdr.hdr.nlmsg_len = NLMSG_LENGTH(sizeof(hdr.gen));
hdr.hdr.nlmsg_flags = NLM_F_REQUEST | NLM_F_DUMP;
hdr.gen.rtgen_family = family_;
} else {
switch (type_) {
case kTypeLink:
if (!EncodeLink(&hdr)) {
return ByteString();
}
break;
case kTypeAddress:
if (!EncodeAddress(&hdr)) {
return ByteString();
}
break;
case kTypeRoute:
if (!EncodeRoute(&hdr)) {
return ByteString();
}
break;
default:
NOTREACHED();
}
}
size_t header_length = hdr.hdr.nlmsg_len;
ByteString attributes;
base::hash_map<uint16, ByteString>::const_iterator attr;
for (attr = attributes_.begin(); attr != attributes_.end(); ++attr) {
size_t len = RTA_LENGTH(attr->second.GetLength());
hdr.hdr.nlmsg_len = NLMSG_ALIGN(hdr.hdr.nlmsg_len) + RTA_ALIGN(len);
struct rtattr rt_attr = { static_cast<unsigned short>(len), attr->first };
ByteString attr_header(reinterpret_cast<unsigned char *>(&rt_attr),
sizeof(rt_attr));
attr_header.Resize(RTA_ALIGN(attr_header.GetLength()));
attributes.Append(attr_header);
ByteString attr_data(attr->second);
attr_data.Resize(RTA_ALIGN(attr_data.GetLength()));
attributes.Append(attr_data);
}
ByteString packet(reinterpret_cast<unsigned char *>(&hdr), header_length);
packet.Append(attributes);
return packet;
}
bool RTNLMessage::EncodeLink(RTNLHeader *hdr) const {
switch (mode_) {
case kModeAdd:
hdr->hdr.nlmsg_type = RTM_NEWLINK;
break;
case kModeDelete:
hdr->hdr.nlmsg_type = RTM_DELLINK;
break;
case kModeQuery:
hdr->hdr.nlmsg_type = RTM_GETLINK;
break;
default:
NOTIMPLEMENTED();
return false;
}
hdr->hdr.nlmsg_len = NLMSG_LENGTH(sizeof(hdr->ifi));
hdr->ifi.ifi_family = family_;
hdr->ifi.ifi_index = interface_index_;
hdr->ifi.ifi_type = link_status_.type;
hdr->ifi.ifi_flags = link_status_.flags;
hdr->ifi.ifi_change = link_status_.change;
return true;
}
bool RTNLMessage::EncodeAddress(RTNLHeader *hdr) const {
switch (mode_) {
case kModeAdd:
hdr->hdr.nlmsg_type = RTM_NEWADDR;
break;
case kModeDelete:
hdr->hdr.nlmsg_type = RTM_DELADDR;
break;
case kModeQuery:
hdr->hdr.nlmsg_type = RTM_GETADDR;
break;
default:
NOTIMPLEMENTED();
return false;
}
hdr->hdr.nlmsg_len = NLMSG_LENGTH(sizeof(hdr->ifa));
hdr->ifa.ifa_family = family_;
hdr->ifa.ifa_prefixlen = address_status_.prefix_len;
hdr->ifa.ifa_flags = address_status_.flags;
hdr->ifa.ifa_scope = address_status_.scope;
hdr->ifa.ifa_index = interface_index_;
return true;
}
bool RTNLMessage::EncodeRoute(RTNLHeader *hdr) const {
switch (mode_) {
case kModeAdd:
hdr->hdr.nlmsg_type = RTM_NEWROUTE;
break;
case kModeDelete:
hdr->hdr.nlmsg_type = RTM_DELROUTE;
break;
case kModeQuery:
hdr->hdr.nlmsg_type = RTM_GETROUTE;
break;
default:
NOTIMPLEMENTED();
return false;
}
hdr->hdr.nlmsg_len = NLMSG_LENGTH(sizeof(hdr->rtm));
hdr->rtm.rtm_family = family_;
hdr->rtm.rtm_dst_len = route_status_.dst_prefix;
hdr->rtm.rtm_src_len = route_status_.src_prefix;
hdr->rtm.rtm_table = route_status_.table;
hdr->rtm.rtm_protocol = route_status_.protocol;
hdr->rtm.rtm_scope = route_status_.scope;
hdr->rtm.rtm_type = route_status_.type;
hdr->rtm.rtm_flags = route_status_.flags;
return true;
}
void RTNLMessage::Reset() {
mode_ = kModeUnknown;
type_ = kTypeUnknown;
flags_ = 0;
seq_ = 0;
pid_ = 0;
interface_index_ = 0;
family_ = IPAddress::kFamilyUnknown;
link_status_ = LinkStatus();
address_status_ = AddressStatus();
route_status_ = RouteStatus();
attributes_.clear();
}
} // namespace shill