Kea 2.2.0
pkt.cc
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1// Copyright (C) 2014-2022 Internet Systems Consortium, Inc. ("ISC")
2//
3// This Source Code Form is subject to the terms of the Mozilla Public
4// License, v. 2.0. If a copy of the MPL was not distributed with this
5// file, You can obtain one at http://mozilla.org/MPL/2.0/.
6
7#include <config.h>
8#include <utility>
9#include <dhcp/pkt.h>
10#include <dhcp/iface_mgr.h>
11#include <dhcp/hwaddr.h>
12#include <vector>
13
14namespace isc {
15namespace dhcp {
16
17Pkt::Pkt(uint32_t transid, const isc::asiolink::IOAddress& local_addr,
18 const isc::asiolink::IOAddress& remote_addr, uint16_t local_port,
19 uint16_t remote_port)
20 : transid_(transid), iface_(""), ifindex_(-1), local_addr_(local_addr),
21 remote_addr_(remote_addr), local_port_(local_port),
22 remote_port_(remote_port), buffer_out_(0), copy_retrieved_options_(false) {
23}
24
25Pkt::Pkt(const uint8_t* buf, uint32_t len, const isc::asiolink::IOAddress& local_addr,
26 const isc::asiolink::IOAddress& remote_addr, uint16_t local_port,
27 uint16_t remote_port)
28 : transid_(0), iface_(""), ifindex_(-1), local_addr_(local_addr),
29 remote_addr_(remote_addr), local_port_(local_port),
30 remote_port_(remote_port), buffer_out_(0), copy_retrieved_options_(false) {
31 if (len != 0) {
32 if (buf == NULL) {
33 isc_throw(InvalidParameter, "data buffer passed to Pkt is NULL");
34 }
35 data_.resize(len);
36 memcpy(&data_[0], buf, len);
37 }
38}
39
40void
42 options_.insert(std::pair<int, OptionPtr>(opt->getType(), opt));
43}
44
46Pkt::getNonCopiedOption(const uint16_t type) const {
47 const auto& x = options_.find(type);
48 if (x != options_.end()) {
49 return (x->second);
50 }
51 return (OptionPtr());
52}
53
55Pkt::getOption(const uint16_t type) {
56 const auto& x = options_.find(type);
57 if (x != options_.end()) {
59 OptionPtr option_copy = x->second->clone();
60 x->second = option_copy;
61 }
62 return (x->second);
63 }
64 return (OptionPtr()); // NULL
65}
66
67bool
68Pkt::delOption(uint16_t type) {
69 const auto& x = options_.find(type);
70 if (x != options_.end()) {
71 options_.erase(x);
72 return (true); // delete successful
73 } else {
74 return (false); // can't find option to be deleted
75 }
76}
77
78bool
79Pkt::inClass(const std::string& client_class) {
80 return (classes_.contains(client_class));
81}
82
83void
84Pkt::addClass(const std::string& client_class, bool required) {
85 // Always have ALL first.
86 if (classes_.empty()) {
87 classes_.insert("ALL");
88 }
89 ClientClasses& classes = !required ? classes_ : required_classes_;
90 if (!classes.contains(client_class)) {
91 classes.insert(client_class);
92 }
93}
94
95void
97 timestamp_ = boost::posix_time::microsec_clock::universal_time();
98}
99
101 if (!data_.empty()) {
102 buffer_out_.writeData(&data_[0], data_.size());
103 }
104}
105
106void
107Pkt::setRemoteHWAddr(const uint8_t htype, const uint8_t hlen,
108 const std::vector<uint8_t>& hw_addr) {
109 setHWAddrMember(htype, hlen, hw_addr, remote_hwaddr_);
110}
111
112void
114 if (!hw_addr) {
115 isc_throw(BadValue, "Setting remote HW address to NULL is"
116 << " forbidden.");
117 }
118 remote_hwaddr_ = hw_addr;
119}
120
121void
122Pkt::setHWAddrMember(const uint8_t htype, const uint8_t,
123 const std::vector<uint8_t>& hw_addr,
124 HWAddrPtr& storage) {
125 storage.reset(new HWAddr(hw_addr, htype));
126}
127
129Pkt::getMAC(uint32_t hw_addr_src) {
130 HWAddrPtr mac;
131
133
134 // Method 1: from raw sockets.
135 if (hw_addr_src & HWAddr::HWADDR_SOURCE_RAW) {
136 mac = getRemoteHWAddr();
137 if (mac) {
138 mac->source_ = HWAddr::HWADDR_SOURCE_RAW;
139 return (mac);
140 } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_RAW) {
141 // If we're interested only in RAW sockets as source of that info,
142 // there's no point in trying other options.
143 return (HWAddrPtr());
144 }
145 }
146
147 // Method 2: From client link-layer address option inserted by a relay
150 if (mac) {
151 return (mac);
152 } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_CLIENT_ADDR_RELAY_OPTION) {
153 // If we're interested only in RFC6939 link layer address as source
154 // of that info, there's no point in trying other options.
155 return (HWAddrPtr());
156 }
157 }
158
159 // Method 3: Extracted from DUID-LLT or DUID-LL
160 if(hw_addr_src & HWAddr::HWADDR_SOURCE_DUID) {
161 mac = getMACFromDUID();
162 if (mac) {
163 return (mac);
164 } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_DUID) {
165 // If the only source allowed is DUID then we can skip the other
166 // methods.
167 return (HWAddrPtr());
168 }
169 }
170
171 // Method 4: Extracted from source IPv6 link-local address
172 if (hw_addr_src & HWAddr::HWADDR_SOURCE_IPV6_LINK_LOCAL) {
174 if (mac) {
175 return (mac);
176 } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_IPV6_LINK_LOCAL) {
177 // If we're interested only in link-local addr as source of that
178 // info, there's no point in trying other options.
179 return (HWAddrPtr());
180 }
181 }
182
183 // Method 5: From remote-id option inserted by a relay
184 if(hw_addr_src & HWAddr::HWADDR_SOURCE_REMOTE_ID) {
186 if (mac) {
187 return (mac);
188 } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_REMOTE_ID) {
189 // If the only source allowed is remote-id option then we can skip
190 // the other methods.
191 return (HWAddrPtr());
192 }
193 }
194
195 // Method 6: From subscriber-id option inserted by a relay
196
197 // Method 7: From docsis options
198 if (hw_addr_src & HWAddr::HWADDR_SOURCE_DOCSIS_CMTS) {
199 mac = getMACFromDocsisCMTS();
200 if (mac) {
201 return (mac);
202 } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_DOCSIS_CMTS) {
203 // If we're interested only in CMTS options as a source of that
204 // info, there's no point in trying other options.
205 return (HWAddrPtr());
206 }
207 }
208
209 // Method 8: From docsis options
210 if (hw_addr_src & HWAddr::HWADDR_SOURCE_DOCSIS_MODEM) {
211 mac = getMACFromDocsisModem();
212 if (mac) {
213 return (mac);
214 } else if (hw_addr_src == HWAddr::HWADDR_SOURCE_DOCSIS_MODEM) {
215 // If we're interested only in CMTS options as a source of that
216 // info, there's no point in trying other options.
217 return (HWAddrPtr());
218 }
219 }
220
221 // Ok, none of the methods were suitable. Return NULL.
222 return (HWAddrPtr());
223}
224
227 HWAddrPtr mac;
228
229 if (addr.isV6LinkLocal()) {
230 std::vector<uint8_t> bin = addr.toBytes();
231
232 // Double check that it's of appropriate size
233 if ((bin.size() == isc::asiolink::V6ADDRESS_LEN) &&
234 // Check that it's link-local (starts with fe80).
235 (bin[0] == 0xfe) && (bin[1] == 0x80) &&
236 // Check that u bit is set and g is clear.
237 // See Section 2.5.1 of RFC2373 for details.
238 ((bin[8] & 3) == 2) &&
239 // And that the IID is of EUI-64 type.
240 (bin[11] == 0xff) && (bin[12] == 0xfe)) {
241
242 // Remove 8 most significant bytes
243 bin.erase(bin.begin(), bin.begin() + 8);
244
245 // Ok, we're down to EUI-64 only now: XX:XX:XX:ff:fe:XX:XX:XX
246 bin.erase(bin.begin() + 3, bin.begin() + 5);
247
248 // MAC-48 to EUI-64 involves inverting u bit (see explanation
249 // in Section 2.5.1 of RFC2373). We need to revert that.
250 bin[0] = bin[0] ^ 2;
251
252 // Let's get the interface this packet was received on.
253 // We need it to get hardware type
255 uint16_t hwtype = 0; // not specified
256 if (iface) {
257 hwtype = iface->getHWType();
258 }
259
260 mac.reset(new HWAddr(bin, hwtype));
262 }
263 }
264
265 return (mac);
266}
267
268} // end of namespace isc::dhcp
269} // end of namespace isc
A generic exception that is thrown if a parameter given to a method is considered invalid in that con...
A generic exception that is thrown if a parameter given to a method or function is considered invalid...
Container for storing client class names.
Definition: classify.h:70
bool contains(const ClientClass &x) const
returns if class x belongs to the defined classes
Definition: classify.cc:49
void insert(const ClientClass &class_name)
Insert an element.
Definition: classify.h:90
bool empty() const
Check if classes is empty.
Definition: classify.h:100
static IfaceMgr & instance()
IfaceMgr is a singleton class.
Definition: iface_mgr.cc:53
IfacePtr getIface(int ifindex)
Returns interface specified interface index.
Definition: iface_mgr.cc:902
bool delOption(uint16_t type)
Attempts to delete first suboption of requested type.
Definition: pkt.cc:68
virtual HWAddrPtr getMACFromDocsisModem()=0
Attempts to extract MAC/Hardware address from DOCSIS options inserted by the modem itself.
virtual HWAddrPtr getMACFromDocsisCMTS()=0
Attempts to extract MAC/Hardware address from DOCSIS options inserted by the CMTS (the relay agent)
ClientClasses required_classes_
Classes which are required to be evaluated.
Definition: pkt.h:604
void repack()
Copies content of input buffer to output buffer.
Definition: pkt.cc:100
virtual HWAddrPtr getMACFromRemoteIdRelayOption()=0
Attempts to obtain MAC address from remote-id relay option.
OptionBuffer data_
Unparsed data (in received packets).
Definition: pkt.h:312
HWAddrPtr getRemoteHWAddr() const
Returns the remote HW address obtained from raw sockets.
Definition: pkt.h:559
virtual HWAddrPtr getMACFromSrcLinkLocalAddr()=0
Attempts to obtain MAC address from source link-local IPv6 address.
ClientClasses classes_
Classes this packet belongs to.
Definition: pkt.h:596
virtual size_t len()=0
Returns packet size in binary format.
HWAddrPtr remote_hwaddr_
Definition: pkt.h:776
isc::dhcp::OptionCollection options_
Collection of options present in this message.
Definition: pkt.h:614
isc::util::OutputBuffer buffer_out_
Output buffer (used during message transmission)
Definition: pkt.h:764
virtual HWAddrPtr getMACFromDUID()=0
Attempts to obtain MAC address from DUID-LL or DUID-LLT.
Pkt(uint32_t transid, const isc::asiolink::IOAddress &local_addr, const isc::asiolink::IOAddress &remote_addr, uint16_t local_port, uint16_t remote_port)
Constructor.
Definition: pkt.cc:17
OptionPtr getOption(const uint16_t type)
Returns the first option of specified type.
Definition: pkt.cc:55
void setRemoteHWAddr(const HWAddrPtr &hw_addr)
Sets remote hardware address.
Definition: pkt.cc:113
bool inClass(const isc::dhcp::ClientClass &client_class)
Checks whether a client belongs to a given class.
Definition: pkt.cc:79
virtual HWAddrPtr getMACFromIPv6RelayOpt()=0
Attempts to obtain MAC address from relay option client-linklayer-addr.
boost::posix_time::ptime timestamp_
packet timestamp
Definition: pkt.h:773
HWAddrPtr getMAC(uint32_t hw_addr_src)
Returns MAC address.
Definition: pkt.cc:129
void updateTimestamp()
Update packet timestamp.
Definition: pkt.cc:96
bool copy_retrieved_options_
Indicates if a copy of the retrieved option should be returned when Pkt::getOption is called.
Definition: pkt.h:770
std::string iface_
Name of the network interface the packet was received/to be sent over.
Definition: pkt.h:729
void addClass(const isc::dhcp::ClientClass &client_class, bool required=false)
Adds packet to a specified class.
Definition: pkt.cc:84
OptionPtr getNonCopiedOption(const uint16_t type) const
Returns the first option of specified type without copying.
Definition: pkt.cc:46
HWAddrPtr getMACFromIPv6(const isc::asiolink::IOAddress &addr)
Attempts to convert IPv6 address into MAC.
Definition: pkt.cc:226
virtual void addOption(const OptionPtr &opt)
Adds an option to this packet.
Definition: pkt.cc:41
void writeData(const void *data, size_t len)
Copy an arbitrary length of data into the buffer.
Definition: buffer.h:550
#define isc_throw(type, stream)
A shortcut macro to insert known values into exception arguments.
static const uint32_t HWADDR_SOURCE_RAW
Obtained first hand from raw socket (100% reliable).
Definition: hwaddr.h:44
static const uint32_t HWADDR_SOURCE_REMOTE_ID
A relay can insert remote-id.
Definition: hwaddr.h:63
static const uint32_t HWADDR_SOURCE_CLIENT_ADDR_RELAY_OPTION
Get it from RFC6939 option.
Definition: hwaddr.h:59
static const uint32_t HWADDR_SOURCE_IPV6_LINK_LOCAL
Extracted from IPv6 link-local address.
Definition: hwaddr.h:53
static const uint32_t HWADDR_SOURCE_DOCSIS_MODEM
A cable modem (acting as DHCP client) that supports DOCSIS standard can insert DOCSIS options that co...
Definition: hwaddr.h:79
static const uint32_t HWADDR_SOURCE_DUID
Extracted from DUID-LL or DUID-LLT (not 100% reliable as the client can send fake DUID).
Definition: hwaddr.h:48
static const uint32_t HWADDR_SOURCE_DOCSIS_CMTS
A CMTS (acting as DHCP relay agent) that supports DOCSIS standard can insert DOCSIS options that cont...
Definition: hwaddr.h:73
boost::shared_ptr< Iface > IfacePtr
Type definition for the pointer to an Iface object.
Definition: iface_mgr.h:487
boost::shared_ptr< HWAddr > HWAddrPtr
Shared pointer to a hardware address structure.
Definition: hwaddr.h:154
boost::shared_ptr< Option > OptionPtr
Definition: option.h:36
Defines the logger used by the top-level component of kea-lfc.
Hardware type that represents information from DHCPv4 packet.
Definition: hwaddr.h:20