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      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 CRYPTO_NSS_UTIL_H_
      6 #define CRYPTO_NSS_UTIL_H_
      7 
      8 #include <string>
      9 #include "base/basictypes.h"
     10 #include "crypto/crypto_export.h"
     11 
     12 namespace base {
     13 class FilePath;
     14 class Lock;
     15 class Time;
     16 }  // namespace base
     17 
     18 // This file specifically doesn't depend on any NSS or NSPR headers because it
     19 // is included by various (non-crypto) parts of chrome to call the
     20 // initialization functions.
     21 namespace crypto {
     22 
     23 // The TPMToken name used for the NSS slot opened by ScopedTestNSSDB.
     24 CRYPTO_EXPORT extern const char kTestTPMTokenName[];
     25 
     26 #if defined(USE_NSS)
     27 // EarlySetupForNSSInit performs lightweight setup which must occur before the
     28 // process goes multithreaded. This does not initialise NSS. For test, see
     29 // EnsureNSSInit.
     30 CRYPTO_EXPORT void EarlySetupForNSSInit();
     31 #endif
     32 
     33 // Initialize NRPR if it isn't already initialized.  This function is
     34 // thread-safe, and NSPR will only ever be initialized once.
     35 CRYPTO_EXPORT void EnsureNSPRInit();
     36 
     37 // Initialize NSS safely for strict sandboxing.  This function tells NSS to not
     38 // load user security modules, and makes sure NSS will have proper entropy in a
     39 // restricted, sandboxed environment.
     40 //
     41 // As a defense in depth measure, this function should be called in a sandboxed
     42 // environment.  That way, in the event of a bug, NSS will still not be able to
     43 // load security modules that could expose private data and keys.
     44 //
     45 // Make sure to get an LGTM from the Chrome Security Team if you use this.
     46 CRYPTO_EXPORT void InitNSSSafely();
     47 
     48 // Initialize NSS if it isn't already initialized.  This must be called before
     49 // any other NSS functions.  This function is thread-safe, and NSS will only
     50 // ever be initialized once.
     51 CRYPTO_EXPORT void EnsureNSSInit();
     52 
     53 // Call this before calling EnsureNSSInit() will force NSS to initialize
     54 // without a persistent DB.  This is used for the special case where access of
     55 // persistent DB is prohibited.
     56 //
     57 // TODO(hclam): Isolate loading default root certs.
     58 //
     59 // NSS will be initialized without loading any user security modules, including
     60 // the built-in root certificates module. User security modules need to be
     61 // loaded manually after NSS initialization.
     62 //
     63 // If EnsureNSSInit() is called before then this function has no effect.
     64 //
     65 // Calling this method only has effect on Linux.
     66 //
     67 // WARNING: Use this with caution.
     68 CRYPTO_EXPORT void ForceNSSNoDBInit();
     69 
     70 // This method is used to disable checks in NSS when used in a forked process.
     71 // NSS checks whether it is running a forked process to avoid problems when
     72 // using user security modules in a forked process.  However if we are sure
     73 // there are no modules loaded before the process is forked then there is no
     74 // harm disabling the check.
     75 //
     76 // This method must be called before EnsureNSSInit() to take effect.
     77 //
     78 // WARNING: Use this with caution.
     79 CRYPTO_EXPORT void DisableNSSForkCheck();
     80 
     81 // Load NSS library files. This function has no effect on Mac and Windows.
     82 // This loads the necessary NSS library files so that NSS can be initialized
     83 // after loading additional library files is disallowed, for example when the
     84 // sandbox is active.
     85 //
     86 // Note that this does not load libnssckbi.so which contains the root
     87 // certificates.
     88 CRYPTO_EXPORT void LoadNSSLibraries();
     89 
     90 // Check if the current NSS version is greater than or equals to |version|.
     91 // A sample version string is "3.12.3".
     92 bool CheckNSSVersion(const char* version);
     93 
     94 #if defined(OS_CHROMEOS)
     95 // Open the r/w nssdb that's stored inside the user's encrypted home
     96 // directory.  This is the default slot returned by
     97 // GetPublicNSSKeySlot().
     98 CRYPTO_EXPORT void OpenPersistentNSSDB();
     99 
    100 // Indicates that NSS should load the Chaps library so that we
    101 // can access the TPM through NSS.  Once this is called,
    102 // GetPrivateNSSKeySlot() will return the TPM slot if one was found.
    103 CRYPTO_EXPORT void EnableTPMTokenForNSS();
    104 
    105 // Get name and user PIN for the built-in TPM token on ChromeOS.
    106 // Either one can safely be NULL.  Should only be called after
    107 // EnableTPMTokenForNSS has been called with a non-null delegate.
    108 CRYPTO_EXPORT void GetTPMTokenInfo(std::string* token_name,
    109                                    std::string* user_pin);
    110 
    111 // Returns true if the TPM is owned and PKCS#11 initialized with the
    112 // user and security officer PINs, and has been enabled in NSS by
    113 // calling EnableTPMForNSS, and Chaps has been successfully
    114 // loaded into NSS.
    115 CRYPTO_EXPORT bool IsTPMTokenReady();
    116 
    117 // Initialize the TPM token.  Does nothing if it is already initialized.
    118 CRYPTO_EXPORT bool InitializeTPMToken(const std::string& token_name,
    119                                       const std::string& user_pin);
    120 #endif
    121 
    122 // Convert a NSS PRTime value into a base::Time object.
    123 // We use a int64 instead of PRTime here to avoid depending on NSPR headers.
    124 CRYPTO_EXPORT base::Time PRTimeToBaseTime(int64 prtime);
    125 
    126 // Convert a base::Time object into a PRTime value.
    127 // We use a int64 instead of PRTime here to avoid depending on NSPR headers.
    128 CRYPTO_EXPORT int64 BaseTimeToPRTime(base::Time time);
    129 
    130 #if defined(USE_NSS)
    131 // Exposed for unittests only.
    132 // TODO(mattm): When NSS 3.14 is the minimum version required,
    133 // switch back to using a separate user DB for each test.
    134 // Because of https://bugzilla.mozilla.org/show_bug.cgi?id=588269 , the
    135 // opened user DB is not automatically closed.
    136 class CRYPTO_EXPORT_PRIVATE ScopedTestNSSDB {
    137  public:
    138   ScopedTestNSSDB();
    139   ~ScopedTestNSSDB();
    140 
    141   bool is_open() { return is_open_; }
    142 
    143  private:
    144   bool is_open_;
    145   DISALLOW_COPY_AND_ASSIGN(ScopedTestNSSDB);
    146 };
    147 
    148 // NSS has a bug which can cause a deadlock or stall in some cases when writing
    149 // to the certDB and keyDB. It also has a bug which causes concurrent key pair
    150 // generations to scribble over each other. To work around this, we synchronize
    151 // writes to the NSS databases with a global lock. The lock is hidden beneath a
    152 // function for easy disabling when the bug is fixed. Callers should allow for
    153 // it to return NULL in the future.
    154 //
    155 // See https://bugzilla.mozilla.org/show_bug.cgi?id=564011
    156 base::Lock* GetNSSWriteLock();
    157 
    158 // A helper class that acquires the NSS write Lock while the AutoNSSWriteLock
    159 // is in scope.
    160 class CRYPTO_EXPORT AutoNSSWriteLock {
    161  public:
    162   AutoNSSWriteLock();
    163   ~AutoNSSWriteLock();
    164  private:
    165   base::Lock *lock_;
    166   DISALLOW_COPY_AND_ASSIGN(AutoNSSWriteLock);
    167 };
    168 
    169 #endif  // defined(USE_NSS)
    170 
    171 }  // namespace crypto
    172 
    173 #endif  // CRYPTO_NSS_UTIL_H_
    174