Home | History | Annotate | Download | only in cert
      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_CERT_X509_UTIL_MAC_H_
      6 #define NET_CERT_X509_UTIL_MAC_H_
      7 
      8 #include <CoreFoundation/CFArray.h>
      9 #include <Security/Security.h>
     10 
     11 #include <string>
     12 
     13 #include "base/basictypes.h"
     14 #include "net/base/net_export.h"
     15 
     16 namespace net {
     17 
     18 namespace x509_util {
     19 
     20 // Creates a security policy for certificates used as client certificates
     21 // in SSL.
     22 // If a policy is successfully created, it will be stored in
     23 // |*policy| and ownership transferred to the caller.
     24 OSStatus NET_EXPORT CreateSSLClientPolicy(SecPolicyRef* policy);
     25 
     26 // Create an SSL server policy. While certificate name validation will be
     27 // performed by SecTrustEvaluate(), it has the following limitations:
     28 // - Doesn't support IP addresses in dotted-quad literals (127.0.0.1)
     29 // - Doesn't support IPv6 addresses
     30 // - Doesn't support the iPAddress subjectAltName
     31 // Providing the hostname is necessary in order to locate certain user or
     32 // system trust preferences, such as those created by Safari. Preferences
     33 // created by Keychain Access do not share this requirement.
     34 // On success, stores the resultant policy in |*policy| and returns noErr.
     35 OSStatus NET_EXPORT CreateSSLServerPolicy(const std::string& hostname,
     36                                           SecPolicyRef* policy);
     37 
     38 // Creates a security policy for basic X.509 validation. If the policy is
     39 // successfully created, it will be stored in |*policy| and ownership
     40 // transferred to the caller.
     41 OSStatus NET_EXPORT CreateBasicX509Policy(SecPolicyRef* policy);
     42 
     43 // Creates security policies to control revocation checking (OCSP and CRL).
     44 // If |enable_revocation_checking| is true, revocation checking will be
     45 // explicitly enabled.
     46 // If |enable_revocation_checking| is false, but |enable_ev_checking| is
     47 // true, then the system policies for EV checking (which include checking
     48 // for an online OCSP response) will be permitted. However, if the OS
     49 // does not believe the certificate is EV, no revocation checking will be
     50 // performed.
     51 // If both are false, then the policies returned will be explicitly
     52 // prohibited from accessing the network or the local cache, regardless of
     53 // system settings.
     54 // If the policies are successfully created, they will be appended to
     55 // |policies|.
     56 OSStatus NET_EXPORT CreateRevocationPolicies(bool enable_revocation_checking,
     57                                              bool enable_ev_checking,
     58                                              CFMutableArrayRef policies);
     59 
     60 // Wrapper for a CSSM_DATA_PTR that was obtained via one of the CSSM field
     61 // accessors (such as CSSM_CL_CertGet[First/Next]Value or
     62 // CSSM_CL_CertGet[First/Next]CachedValue).
     63 class CSSMFieldValue {
     64  public:
     65   CSSMFieldValue();
     66   CSSMFieldValue(CSSM_CL_HANDLE cl_handle,
     67                  const CSSM_OID* oid,
     68                  CSSM_DATA_PTR field);
     69   ~CSSMFieldValue();
     70 
     71   CSSM_OID_PTR oid() const { return oid_; }
     72   CSSM_DATA_PTR field() const { return field_; }
     73 
     74   // Returns the field as if it was an arbitrary type - most commonly, by
     75   // interpreting the field as a specific CSSM/CDSA parsed type, such as
     76   // CSSM_X509_SUBJECT_PUBLIC_KEY_INFO or CSSM_X509_ALGORITHM_IDENTIFIER.
     77   // An added check is applied to ensure that the current field is large
     78   // enough to actually contain the requested type.
     79   template <typename T> const T* GetAs() const {
     80     if (!field_ || field_->Length < sizeof(T))
     81       return NULL;
     82     return reinterpret_cast<const T*>(field_->Data);
     83   }
     84 
     85   void Reset(CSSM_CL_HANDLE cl_handle,
     86              CSSM_OID_PTR oid,
     87              CSSM_DATA_PTR field);
     88 
     89  private:
     90   CSSM_CL_HANDLE cl_handle_;
     91   CSSM_OID_PTR oid_;
     92   CSSM_DATA_PTR field_;
     93 
     94   DISALLOW_COPY_AND_ASSIGN(CSSMFieldValue);
     95 };
     96 
     97 // CSSMCachedCertificate is a container class that is used to wrap the
     98 // CSSM_CL_CertCache APIs and provide safe and efficient access to
     99 // certificate fields in their CSSM form.
    100 //
    101 // To provide efficient access to certificate/CRL fields, CSSM provides an
    102 // API/SPI to "cache" a certificate/CRL. The exact meaning of a cached
    103 // certificate is not defined by CSSM, but is documented to generally be some
    104 // intermediate or parsed form of the certificate. In the case of Apple's
    105 // CSSM CL implementation, the intermediate form is the parsed certificate
    106 // stored in an internal format (which happens to be NSS). By caching the
    107 // certificate, callers that wish to access multiple fields (such as subject,
    108 // issuer, and validity dates) do not need to repeatedly parse the entire
    109 // certificate, nor are they forced to convert all fields from their NSS types
    110 // to their CSSM equivalents. This latter point is especially helpful when
    111 // running on OS X 10.5, as it will fail to convert some fields that reference
    112 // unsupported algorithms, such as ECC.
    113 class CSSMCachedCertificate {
    114  public:
    115   CSSMCachedCertificate();
    116   ~CSSMCachedCertificate();
    117 
    118   // Initializes the CSSMCachedCertificate by caching the specified
    119   // |os_cert_handle|. On success, returns noErr.
    120   // Note: Once initialized, the cached certificate should only be accessed
    121   // from a single thread.
    122   OSStatus Init(SecCertificateRef os_cert_handle);
    123 
    124   // Fetches the first value for the field associated with |field_oid|.
    125   // If |field_oid| is a valid OID and is present in the current certificate,
    126   // returns CSSM_OK and stores the first value in |field|. If additional
    127   // values are associated with |field_oid|, they are ignored.
    128   OSStatus GetField(const CSSM_OID* field_oid, CSSMFieldValue* field) const;
    129 
    130  private:
    131   CSSM_CL_HANDLE cl_handle_;
    132   CSSM_HANDLE cached_cert_handle_;
    133 };
    134 
    135 }  // namespace x509_util
    136 
    137 }  // namespace net
    138 
    139 #endif  // NET_CERT_X509_UTIL_MAC_H_
    140