1 // Copyright (c) 2012 The Chromium Authors. All rights reserved.
2 // Use of this source code is governed by a BSD-style license that can be
3 // found in the LICENSE file.
5 #ifndef NET_HTTP_TRANSPORT_SECURITY_STATE_H_
6 #define NET_HTTP_TRANSPORT_SECURITY_STATE_H_
13 #include "base/basictypes.h"
14 #include "base/gtest_prod_util.h"
15 #include "base/threading/non_thread_safe.h"
16 #include "base/time/time.h"
17 #include "net/base/net_export.h"
18 #include "net/cert/x509_cert_types.h"
19 #include "net/cert/x509_certificate.h"
25 // Tracks which hosts have enabled strict transport security and/or public
28 // This object manages the in-memory store. Register a Delegate with
29 // |SetDelegate| to persist the state to disk.
31 // HTTP strict transport security (HSTS) is defined in
32 // http://tools.ietf.org/html/ietf-websec-strict-transport-sec, and
33 // HTTP-based dynamic public key pinning (HPKP) is defined in
34 // http://tools.ietf.org/html/ietf-websec-key-pinning.
35 class NET_EXPORT TransportSecurityState
36 : NON_EXPORTED_BASE(public base::NonThreadSafe) {
38 class NET_EXPORT Delegate {
40 // This function may not block and may be called with internal locks held.
41 // Thus it must not reenter the TransportSecurityState object.
42 virtual void StateIsDirty(TransportSecurityState* state) = 0;
45 virtual ~Delegate() {}
48 TransportSecurityState();
49 ~TransportSecurityState();
51 // A DomainState describes the transport security state (required upgrade
52 // to HTTPS, and/or any public key pins).
53 class NET_EXPORT DomainState {
56 // These numbers must match those in hsts_view.js, function modeToString.
65 // The absolute time (UTC) when the |upgrade_mode| (and other state) was
67 base::Time last_observed;
69 // The absolute time (UTC) when the |upgrade_mode|, if set to
70 // MODE_FORCE_HTTPS, downgrades to MODE_DEFAULT.
73 UpgradeMode upgrade_mode;
75 // Are subdomains subject to this policy state?
76 bool include_subdomains;
83 // The absolute time (UTC) when the |spki_hashes| (and other state) were
85 base::Time last_observed;
87 // The absolute time (UTC) when the |spki_hashes| expire.
90 // Optional; hashes of pinned SubjectPublicKeyInfos.
91 HashValueVector spki_hashes;
93 // Optional; hashes of static known-bad SubjectPublicKeyInfos which MUST
94 // NOT intersect with the set of SPKIs in the TLS server's certificate
96 HashValueVector bad_spki_hashes;
98 // Are subdomains subject to this policy state?
99 bool include_subdomains;
102 // Takes a set of SubjectPublicKeyInfo |hashes| and returns true if:
103 // 1) |bad_static_spki_hashes| does not intersect |hashes|; AND
104 // 2) Both |static_spki_hashes| and |dynamic_spki_hashes| are empty
105 // or at least one of them intersects |hashes|.
107 // |{dynamic,static}_spki_hashes| contain trustworthy public key hashes,
108 // any one of which is sufficient to validate the certificate chain in
109 // question. The public keys could be of a root CA, intermediate CA, or
110 // leaf certificate, depending on the security vs. disaster recovery
111 // tradeoff selected. (Pinning only to leaf certifiates increases
112 // security because you no longer trust any CAs, but it hampers disaster
113 // recovery because you can't just get a new certificate signed by the
116 // |bad_static_spki_hashes| contains public keys that we don't want to
118 bool CheckPublicKeyPins(const HashValueVector& hashes,
119 std::string* failure_log) const;
121 // Returns true if any of the HashValueVectors |static_spki_hashes|,
122 // |bad_static_spki_hashes|, or |dynamic_spki_hashes| contains any
124 bool HasPublicKeyPins() const;
126 // ShouldUpgradeToSSL returns true iff HTTP requests should be internally
127 // redirected to HTTPS (also if WS should be upgraded to WSS).
128 bool ShouldUpgradeToSSL() const;
130 // ShouldSSLErrorsBeFatal returns true iff HTTPS errors should cause
131 // hard-fail behavior (e.g. if HSTS is set for the domain).
132 bool ShouldSSLErrorsBeFatal() const;
137 // The following members are not valid when stored in |enabled_hosts_|:
139 // The domain which matched during a search for this DomainState entry.
140 // Updated by |GetDynamicDomainState| and |GetStaticDomainState|.
144 class NET_EXPORT Iterator {
146 explicit Iterator(const TransportSecurityState& state);
149 bool HasNext() const { return iterator_ != end_; }
150 void Advance() { ++iterator_; }
151 const std::string& hostname() const { return iterator_->first; }
152 const DomainState& domain_state() const { return iterator_->second; }
155 std::map<std::string, DomainState>::const_iterator iterator_;
156 std::map<std::string, DomainState>::const_iterator end_;
159 // These functions search for static and dynamic DomainStates, and invoke the
160 // functions of the same name on them. These functions are the primary public
161 // interface; direct access to DomainStates is best left to tests.
162 bool ShouldSSLErrorsBeFatal(const std::string& host, bool sni_enabled);
163 bool ShouldUpgradeToSSL(const std::string& host, bool sni_enabled);
164 bool CheckPublicKeyPins(const std::string& host,
166 bool is_issued_by_known_root,
167 const HashValueVector& hashes,
168 std::string* failure_log);
169 bool HasPublicKeyPins(const std::string& host, bool sni_enabled);
171 // Assign a |Delegate| for persisting the transport security state. If
172 // |NULL|, state will not be persisted. The caller retains
173 // ownership of |delegate|.
174 // Note: This is only used for serializing/deserializing the
175 // TransportSecurityState.
176 void SetDelegate(Delegate* delegate);
178 // Clears all dynamic data (e.g. HSTS and HPKP data).
180 // Does NOT persist changes using the Delegate, as this function is only
181 // used to clear any dynamic data prior to re-loading it from a file.
182 // Note: This is only used for serializing/deserializing the
183 // TransportSecurityState.
184 void ClearDynamicData();
186 // Inserts |state| into |enabled_hosts_| under the key |hashed_host|.
187 // |hashed_host| is already in the internal representation
188 // HashHost(CanonicalizeHost(host)).
189 // Note: This is only used for serializing/deserializing the
190 // TransportSecurityState.
191 void AddOrUpdateEnabledHosts(const std::string& hashed_host,
192 const DomainState& state);
194 // Deletes all dynamic data (e.g. HSTS or HPKP data) created since a given
197 // If any entries are deleted, the new state will be persisted through
198 // the Delegate (if any).
199 void DeleteAllDynamicDataSince(const base::Time& time);
201 // Deletes any dynamic data stored for |host| (e.g. HSTS or HPKP data).
202 // If |host| doesn't have an exact entry then no action is taken. Does
203 // not delete static (i.e. preloaded) data. Returns true iff an entry
206 // If an entry is deleted, the new state will be persisted through
207 // the Delegate (if any).
208 bool DeleteDynamicDataForHost(const std::string& host);
210 // Returns true and updates |*result| iff there is a static (built-in)
211 // DomainState for |host|.
213 // If |sni_enabled| is true, searches the static pins defined for SNI-using
214 // hosts as well as the rest of the pins.
216 // If |host| matches both an exact entry and is a subdomain of another entry,
217 // the exact match determines the return value.
219 // Note that this method is not const because it opportunistically removes
220 // entries that have expired.
221 bool GetStaticDomainState(const std::string& host,
223 DomainState* result) const;
225 // Returns true and updates |*result| iff there is a dynamic DomainState
226 // (learned from HSTS or HPKP headers, or set by the user, or other means) for
229 // If |host| matches both an exact entry and is a subdomain of another entry,
230 // the exact match determines the return value.
232 // Note that this method is not const because it opportunistically removes
233 // entries that have expired.
234 bool GetDynamicDomainState(const std::string& host, DomainState* result);
236 // Processes an HSTS header value from the host, adding entries to
237 // dynamic state if necessary.
238 bool AddHSTSHeader(const std::string& host, const std::string& value);
240 // Processes an HPKP header value from the host, adding entries to
241 // dynamic state if necessary. ssl_info is used to check that
242 // the specified pins overlap with the certificate chain.
243 bool AddHPKPHeader(const std::string& host, const std::string& value,
244 const SSLInfo& ssl_info);
246 // Adds explicitly-specified data as if it was processed from an
247 // HSTS header (used for net-internals and unit tests).
248 bool AddHSTS(const std::string& host, const base::Time& expiry,
249 bool include_subdomains);
251 // Adds explicitly-specified data as if it was processed from an
252 // HPKP header (used for net-internals and unit tests).
253 bool AddHPKP(const std::string& host, const base::Time& expiry,
254 bool include_subdomains, const HashValueVector& hashes);
256 // Returns true iff we have any static public key pins for the |host| and
257 // iff its set of required pins is the set we expect for Google
260 // If |sni_enabled| is true, searches the static pins defined for
261 // SNI-using hosts as well as the rest of the pins.
263 // If |host| matches both an exact entry and is a subdomain of another
264 // entry, the exact match determines the return value.
265 static bool IsGooglePinnedProperty(const std::string& host,
268 // The maximum number of seconds for which we'll cache an HSTS request.
269 static const long int kMaxHSTSAgeSecs;
272 friend class TransportSecurityStateTest;
273 FRIEND_TEST_ALL_PREFIXES(HttpSecurityHeadersTest, UpdateDynamicPKPOnly);
274 FRIEND_TEST_ALL_PREFIXES(HttpSecurityHeadersTest, UpdateDynamicPKPMaxAge0);
275 FRIEND_TEST_ALL_PREFIXES(HttpSecurityHeadersTest, NoClobberPins);
277 typedef std::map<std::string, DomainState> DomainStateMap;
279 // Send an UMA report on pin validation failure, if the host is in a
280 // statically-defined list of domains.
282 // TODO(palmer): This doesn't really belong here, and should be moved into
283 // the exactly one call site. This requires unifying |struct HSTSPreload|
284 // (an implementation detail of this class) with a more generic
285 // representation of first-class DomainStates, and exposing the preloads
286 // to the caller with |GetStaticDomainState|.
287 static void ReportUMAOnPinFailure(const std::string& host);
289 // IsBuildTimely returns true if the current build is new enough ensure that
290 // built in security information (i.e. HSTS preloading and pinning
291 // information) is timely.
292 static bool IsBuildTimely();
294 // Helper method for actually checking pins.
295 bool CheckPublicKeyPinsImpl(const std::string& host,
297 const HashValueVector& hashes,
298 std::string* failure_log);
300 // If a Delegate is present, notify it that the internal state has
304 // Enable TransportSecurity for |host|. |state| supercedes any previous
305 // state for the |host|, including static entries.
307 // The new state for |host| is persisted using the Delegate (if any).
308 void EnableHost(const std::string& host, const DomainState& state);
310 // Converts |hostname| from dotted form ("www.google.com") to the form
311 // used in DNS: "\x03www\x06google\x03com", lowercases that, and returns
313 static std::string CanonicalizeHost(const std::string& hostname);
315 // The set of hosts that have enabled TransportSecurity.
316 DomainStateMap enabled_hosts_;
320 // True if static pins should be used.
321 bool enable_static_pins_;
323 DISALLOW_COPY_AND_ASSIGN(TransportSecurityState);
328 #endif // NET_HTTP_TRANSPORT_SECURITY_STATE_H_