The Tor Browser: toolkit/components/downloads/SQLFunctions.cpp@6474c204b198

Cloned upstream origin tor-browser at tor-browser-31.3.0esr-4.5-1-build1
revision ID fc1c9ff7c1b2defdbc039f12214767608f46423f for hacking purpose.

     1 /* vim: sw=2 ts=2 et lcs=trail\:.,tab\:>~ :

     2  * This Source Code Form is subject to the terms of the Mozilla Public

     3  * License, v. 2.0. If a copy of the MPL was not distributed with this

     4  * file, You can obtain one at http://mozilla.org/MPL/2.0/. */

     6 #include "mozilla/storage.h"

     7 #include "mozilla/storage/Variant.h"

     8 #include "mozilla/mozalloc.h"

     9 #include "nsString.h"

    10 #include "SQLFunctions.h"

    11 #include "nsUTF8Utils.h"

    12 #include "plbase64.h"

    13 #include "prio.h"

    15 // The length of guids that are used by the download manager

    16 #define GUID_LENGTH 12

    18 namespace mozilla {

    19 namespace downloads {

    21 // Keep this file in sync with the GUID-related code in toolkit/places/SQLFunctions.cpp

    22 // and toolkit/places/Helpers.cpp!

    24 ////////////////////////////////////////////////////////////////////////////////

    25 //// GUID Creation Function

    27 //////////////////////////////////////////////////////////////////////////////

    28 //// GenerateGUIDFunction

    30 /* static */

    31 nsresult

    32 GenerateGUIDFunction::create(mozIStorageConnection *aDBConn)

    33 {

    34   nsRefPtr<GenerateGUIDFunction> function = new GenerateGUIDFunction();

    35   nsresult rv = aDBConn->CreateFunction(

    36     NS_LITERAL_CSTRING("generate_guid"), 0, function

    37   );

    38   NS_ENSURE_SUCCESS(rv, rv);

    40   return NS_OK;

    41 }

    43 NS_IMPL_ISUPPORTS(

    44     GenerateGUIDFunction,

    45     mozIStorageFunction

    46 )

    48 static

    49 nsresult

    50 Base64urlEncode(const uint8_t* aBytes,

    51                 uint32_t aNumBytes,

    52                 nsCString& _result)

    53 {

    54   // SetLength does not set aside space for null termination.  PL_Base64Encode

    55   // will not null terminate, however, nsCStrings must be null terminated.  As a

    56   // result, we set the capacity to be one greater than what we need, and the

    57   // length to our desired length.

    58   uint32_t length = (aNumBytes + 2) / 3 * 4; // +2 due to integer math.

    59   NS_ENSURE_TRUE(_result.SetCapacity(length + 1, mozilla::fallible_t()),

    60                  NS_ERROR_OUT_OF_MEMORY);

    61   _result.SetLength(length);

    62   (void)PL_Base64Encode(reinterpret_cast<const char*>(aBytes), aNumBytes,

    63                         _result.BeginWriting());

    65   // base64url encoding is defined in RFC 4648.  It replaces the last two

    66   // alphabet characters of base64 encoding with '-' and '_' respectively.

    67   _result.ReplaceChar('+', '-');

    68   _result.ReplaceChar('/', '_');

    69   return NS_OK;

    70 }

    72 #ifdef XP_WIN

    73 // Included here because windows.h conflicts with the use of mozIStorageError

    74 // above.

    75 #include <windows.h>

    76 #include <wincrypt.h>

    77 #endif

    79 static

    80 nsresult

    81 GenerateRandomBytes(uint32_t aSize,

    82                     uint8_t* _buffer)

    83 {

    84   // On Windows, we'll use its built-in cryptographic API.

    85 #if defined(XP_WIN)

    86   HCRYPTPROV cryptoProvider;

    87   BOOL rc = CryptAcquireContext(&cryptoProvider, 0, 0, PROV_RSA_FULL,

    88                                 CRYPT_VERIFYCONTEXT | CRYPT_SILENT);

    89   if (rc) {

    90     rc = CryptGenRandom(cryptoProvider, aSize, _buffer);

    91     (void)CryptReleaseContext(cryptoProvider, 0);

    92   }

    93   return rc ? NS_OK : NS_ERROR_FAILURE;

    95   // On Unix, we'll just read in from /dev/urandom.

    96 #elif defined(XP_UNIX)

    97   NS_ENSURE_ARG_MAX(aSize, INT32_MAX);

    98   PRFileDesc* urandom = PR_Open("/dev/urandom", PR_RDONLY, 0);

    99   nsresult rv = NS_ERROR_FAILURE;

   100   if (urandom) {

   101     int32_t bytesRead = PR_Read(urandom, _buffer, aSize);

   102     if (bytesRead == static_cast<int32_t>(aSize)) {

   103       rv = NS_OK;

   104     }

   105     (void)PR_Close(urandom);

   106   }

   107   return rv;

   108 #endif

   109 }

   111 nsresult

   112 GenerateGUID(nsCString& _guid)

   113 {

   114   _guid.Truncate();

   116   // Request raw random bytes and base64url encode them.  For each set of three

   117   // bytes, we get one character.

   118   const uint32_t kRequiredBytesLength =

   119     static_cast<uint32_t>(GUID_LENGTH / 4 * 3);

   121   uint8_t buffer[kRequiredBytesLength];

   122   nsresult rv = GenerateRandomBytes(kRequiredBytesLength, buffer);

   123   NS_ENSURE_SUCCESS(rv, rv);

   125   rv = Base64urlEncode(buffer, kRequiredBytesLength, _guid);

   126   NS_ENSURE_SUCCESS(rv, rv);

   128   NS_ASSERTION(_guid.Length() == GUID_LENGTH, "GUID is not the right size!");

   129   return NS_OK;

   130 }

   132 //////////////////////////////////////////////////////////////////////////////

   133 //// mozIStorageFunction

   135 NS_IMETHODIMP

   136 GenerateGUIDFunction::OnFunctionCall(mozIStorageValueArray *aArguments,

   137                                      nsIVariant **_result)

   138 {

   139   nsAutoCString guid;

   140   nsresult rv = GenerateGUID(guid);

   141   NS_ENSURE_SUCCESS(rv, rv);

   143   NS_ADDREF(*_result = new mozilla::storage::UTF8TextVariant(guid));

   144   return NS_OK;

   145 }

   147 } // namespace mozilla

   148 } // namespace downloads

The Tor Browser / file revision