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. 4 5 #ifndef NET_SSL_SSL_CONFIG_SERVICE_H_ 6 #define NET_SSL_SSL_CONFIG_SERVICE_H_ 7 8 #include <vector> 9 10 #include "base/basictypes.h" 11 #include "base/memory/ref_counted.h" 12 #include "base/observer_list.h" 13 #include "base/strings/string_piece.h" 14 #include "net/base/net_export.h" 15 #include "net/cert/cert_status_flags.h" 16 #include "net/cert/crl_set.h" 17 #include "net/cert/x509_certificate.h" 18 19 namespace net { 20 21 // Various TLS/SSL ProtocolVersion values encoded as uint16 22 // struct { 23 // uint8 major; 24 // uint8 minor; 25 // } ProtocolVersion; 26 // The most significant byte is |major|, and the least significant byte 27 // is |minor|. 28 enum { 29 SSL_PROTOCOL_VERSION_SSL3 = 0x0300, 30 SSL_PROTOCOL_VERSION_TLS1 = 0x0301, 31 SSL_PROTOCOL_VERSION_TLS1_1 = 0x0302, 32 SSL_PROTOCOL_VERSION_TLS1_2 = 0x0303, 33 }; 34 35 // A collection of SSL-related configuration settings. 36 struct NET_EXPORT SSLConfig { 37 // Default to revocation checking. 38 // Default to SSL 3.0 ~ default_version_max() on. 39 SSLConfig(); 40 ~SSLConfig(); 41 42 // Returns true if |cert| is one of the certs in |allowed_bad_certs|. 43 // The expected cert status is written to |cert_status|. |*cert_status| can 44 // be NULL if user doesn't care about the cert status. 45 bool IsAllowedBadCert(X509Certificate* cert, CertStatus* cert_status) const; 46 47 // Same as above except works with DER encoded certificates instead 48 // of X509Certificate. 49 bool IsAllowedBadCert(const base::StringPiece& der_cert, 50 CertStatus* cert_status) const; 51 52 // rev_checking_enabled is true if online certificate revocation checking is 53 // enabled (i.e. OCSP and CRL fetching). 54 // 55 // Regardless of this flag, CRLSet checking is always enabled and locally 56 // cached revocation information will be considered. 57 bool rev_checking_enabled; 58 59 // rev_checking_required_local_anchors is true if revocation checking is 60 // required to succeed when certificates chain to local trust anchors (that 61 // is, non-public CAs). If revocation information cannot be obtained, such 62 // certificates will be treated as revoked ("hard-fail"). 63 // Note: This is distinct from rev_checking_enabled. If true, it is 64 // equivalent to also setting rev_checking_enabled, but only when the 65 // certificate chain chains to a local (non-public) trust anchor. 66 bool rev_checking_required_local_anchors; 67 68 // The minimum and maximum protocol versions that are enabled. 69 // SSL 3.0 is 0x0300, TLS 1.0 is 0x0301, TLS 1.1 is 0x0302, and so on. 70 // (Use the SSL_PROTOCOL_VERSION_xxx enumerators defined above.) 71 // SSL 2.0 is not supported. If version_max < version_min, it means no 72 // protocol versions are enabled. 73 uint16 version_min; 74 uint16 version_max; 75 76 // Presorted list of cipher suites which should be explicitly prevented from 77 // being used in addition to those disabled by the net built-in policy. 78 // 79 // By default, all cipher suites supported by the underlying SSL 80 // implementation will be enabled except for: 81 // - Null encryption cipher suites. 82 // - Weak cipher suites: < 80 bits of security strength. 83 // - FORTEZZA cipher suites (obsolete). 84 // - IDEA cipher suites (RFC 5469 explains why). 85 // - Anonymous cipher suites. 86 // - ECDSA cipher suites on platforms that do not support ECDSA signed 87 // certificates, as servers may use the presence of such ciphersuites as a 88 // hint to send an ECDSA certificate. 89 // The ciphers listed in |disabled_cipher_suites| will be removed in addition 90 // to the above list. 91 // 92 // Though cipher suites are sent in TLS as "uint8 CipherSuite[2]", in 93 // big-endian form, they should be declared in host byte order, with the 94 // first uint8 occupying the most significant byte. 95 // Ex: To disable TLS_RSA_WITH_RC4_128_MD5, specify 0x0004, while to 96 // disable TLS_ECDH_ECDSA_WITH_RC4_128_SHA, specify 0xC002. 97 std::vector<uint16> disabled_cipher_suites; 98 99 bool cached_info_enabled; // True if TLS cached info extension is enabled. 100 bool channel_id_enabled; // True if TLS channel ID extension is enabled. 101 bool false_start_enabled; // True if we'll use TLS False Start. 102 103 // If |unrestricted_ssl3_fallback_enabled| is true, SSL 3.0 fallback will be 104 // enabled for all sites. 105 // If |unrestricted_ssl3_fallback_enabled| is false, SSL 3.0 fallback will be 106 // disabled for a site pinned to the Google pin list (indicating that it is a 107 // Google site). 108 bool unrestricted_ssl3_fallback_enabled; 109 110 // TODO(wtc): move the following members to a new SSLParams structure. They 111 // are not SSL configuration settings. 112 113 struct NET_EXPORT CertAndStatus { 114 CertAndStatus(); 115 ~CertAndStatus(); 116 117 std::string der_cert; 118 CertStatus cert_status; 119 }; 120 121 // Add any known-bad SSL certificate (with its cert status) to 122 // |allowed_bad_certs| that should not trigger an ERR_CERT_* error when 123 // calling SSLClientSocket::Connect. This would normally be done in 124 // response to the user explicitly accepting the bad certificate. 125 std::vector<CertAndStatus> allowed_bad_certs; 126 127 // True if we should send client_cert to the server. 128 bool send_client_cert; 129 130 bool verify_ev_cert; // True if we should verify the certificate for EV. 131 132 bool version_fallback; // True if we are falling back to an older protocol 133 // version (one still needs to decrement 134 // version_max). 135 136 // If cert_io_enabled is false, then certificate verification will not 137 // result in additional HTTP requests. (For example: to fetch missing 138 // intermediates or to perform OCSP/CRL fetches.) It also implies that online 139 // revocation checking is disabled. 140 // NOTE: Only used by NSS. 141 bool cert_io_enabled; 142 143 // The list of application level protocols supported. If set, this will 144 // enable Next Protocol Negotiation (if supported). The order of the 145 // protocols doesn't matter expect for one case: if the server supports Next 146 // Protocol Negotiation, but there is no overlap between the server's and 147 // client's protocol sets, then the first protocol in this list will be 148 // requested by the client. 149 std::vector<std::string> next_protos; 150 151 scoped_refptr<X509Certificate> client_cert; 152 }; 153 154 // The interface for retrieving the SSL configuration. This interface 155 // does not cover setting the SSL configuration, as on some systems, the 156 // SSLConfigService objects may not have direct access to the configuration, or 157 // live longer than the configuration preferences. 158 class NET_EXPORT SSLConfigService 159 : public base::RefCountedThreadSafe<SSLConfigService> { 160 public: 161 // Observer is notified when SSL config settings have changed. 162 class NET_EXPORT Observer { 163 public: 164 // Notify observers if SSL settings have changed. We don't check all of the 165 // data in SSLConfig, just those that qualify as a user config change. 166 // The following settings are considered user changes: 167 // rev_checking_enabled 168 // version_min 169 // version_max 170 // disabled_cipher_suites 171 // channel_id_enabled 172 // false_start_enabled 173 virtual void OnSSLConfigChanged() = 0; 174 175 protected: 176 virtual ~Observer() {} 177 }; 178 179 SSLConfigService(); 180 181 // May not be thread-safe, should only be called on the IO thread. 182 virtual void GetSSLConfig(SSLConfig* config) = 0; 183 184 // Sets and gets the current, global CRL set. 185 static void SetCRLSet(scoped_refptr<CRLSet> crl_set); 186 static scoped_refptr<CRLSet> GetCRLSet(); 187 188 // Enables the TLS cached info extension, which allows the server to send 189 // just a digest of its certificate chain. 190 static void EnableCachedInfo(); 191 static bool cached_info_enabled(); 192 193 // Gets the default minimum protocol version. 194 static uint16 default_version_min(); 195 196 // Gets the default maximum protocol version. 197 static uint16 default_version_max(); 198 199 // Is SNI available in this configuration? 200 static bool IsSNIAvailable(SSLConfigService* service); 201 202 // Add an observer of this service. 203 void AddObserver(Observer* observer); 204 205 // Remove an observer of this service. 206 void RemoveObserver(Observer* observer); 207 208 // Calls the OnSSLConfigChanged method of registered observers. Should only be 209 // called on the IO thread. 210 void NotifySSLConfigChange(); 211 212 protected: 213 friend class base::RefCountedThreadSafe<SSLConfigService>; 214 215 virtual ~SSLConfigService(); 216 217 // SetFlags sets the values of several flags based on global configuration. 218 static void SetSSLConfigFlags(SSLConfig* ssl_config); 219 220 // Process before/after config update. 221 void ProcessConfigUpdate(const SSLConfig& orig_config, 222 const SSLConfig& new_config); 223 224 private: 225 ObserverList<Observer> observer_list_; 226 }; 227 228 } // namespace net 229 230 #endif // NET_SSL_SSL_CONFIG_SERVICE_H_ 231