sal/rtl/uuid.cxx

   1 /* -*- Mode: C++; tab-width: 4; indent-tabs-mode: nil; c-basic-offset: 4 -*- */
   2 /*
   3  * This file is part of the LibreOffice project.
   4  *
   5  * This Source Code Form is subject to the terms of the Mozilla Public
   6  * License, v. 2.0. If a copy of the MPL was not distributed with this
   7  * file, You can obtain one at http://mozilla.org/MPL/2.0/.
   8  *
   9  * This file incorporates work covered by the following license notice:
  10  *
  11  *   Licensed to the Apache Software Foundation (ASF) under one or more
  12  *   contributor license agreements. See the NOTICE file distributed
  13  *   with this work for additional information regarding copyright
  14  *   ownership. The ASF licenses this file to you under the Apache
  15  *   License, Version 2.0 (the "License"); you may not use this file
  16  *   except in compliance with the License. You may obtain a copy of
  17  *   the License at http://www.apache.org/licenses/LICENSE-2.0 .
  18  */
  19
  20 #include <mutex>
  21 #include <string.h>
  22 #include <stdlib.h>
  23
  24 #include <rtl/random.h>
  25 #include <rtl/uuid.h>
  26 #include <rtl/digest.h>
  27
  28 #define SWAP_INT16_TO_NETWORK(x)\
  29                { sal_uInt16 y = x;\
  30                  sal_uInt8 *p = reinterpret_cast<sal_uInt8 *>(&(x)); \
  31                  p[0] = static_cast<sal_uInt8>( ( y >> 8 )  & 0xff );\
  32                  p[1] = static_cast<sal_uInt8>( ( y ) & 0xff);\
  33                }
  34
  35 #define SWAP_NETWORK_TO_INT16(x)\
  36                { sal_uInt16 y = x;\
  37                  sal_uInt8 *p = reinterpret_cast<sal_uInt8 *>(&(y));\
  38                  x = ( ( (static_cast<sal_uInt16>(p[0])) & 0xff) << 8 ) |\
  39                      ( (  static_cast<sal_uInt16>(p[1])) & 0xff);\
  40                }
  41 #define SWAP_NETWORK_TO_INT32(x)\
  42                { sal_uInt32 y = x;\
  43                  sal_uInt8 *p = reinterpret_cast<sal_uInt8 *>(&(y)); \
  44                  x = ( ( (static_cast<sal_uInt32>(p[0])) & 0xff) << 24 ) |\
  45                      ( ( (static_cast<sal_uInt32>(p[1])) & 0xff) << 16 ) |\
  46                      ( ( (static_cast<sal_uInt32>(p[2])) & 0xff) << 8  ) |\
  47                      ( (  static_cast<sal_uInt32>(p[3])) & 0xff);\
  48                }
  49
  50 namespace {
  51
  52 struct UUID
  53 {
  54       sal_uInt32          time_low;
  55       sal_uInt16          time_mid;
  56       sal_uInt16          time_hi_and_version;
  57       sal_uInt8           clock_seq_hi_and_reserved;
  58       sal_uInt8           clock_seq_low;
  59       sal_uInt8           node[6];
  60 };
  61
  62 }
  63
  64 static void write_v3( sal_uInt8 *pUuid  )
  65 {
  66     UUID uuid;
  67     // copy to avoid alignment problems
  68     memcpy(&uuid, pUuid, 16);
  69
  70     SWAP_NETWORK_TO_INT16(uuid.time_hi_and_version);
  71
  72     /* put in the variant and version bits */
  73     uuid.time_hi_and_version &= 0x0FFF;
  74     uuid.time_hi_and_version |= (3 << 12);
  75     uuid.clock_seq_hi_and_reserved &= 0x3F;
  76     uuid.clock_seq_hi_and_reserved |= 0x80;
  77
  78     SWAP_INT16_TO_NETWORK(uuid.time_hi_and_version);
  79
  80     memcpy(pUuid, &uuid, 16);
  81 }
  82
  83 extern "C" void SAL_CALL rtl_createUuid(sal_uInt8 *pTargetUUID ,
  84                                         SAL_UNUSED_PARAMETER const sal_uInt8 *,
  85                                         SAL_UNUSED_PARAMETER sal_Bool)
  86 {
  87     {
  88         static rtlRandomPool pool = []() {
  89             rtlRandomPool aPool = rtl_random_createPool();
  90             if (!aPool)
  91             {
  92                 abort();
  93                 // only possible way to signal failure here (rtl_createUuid
  94                 // being part of a fixed C API)
  95             }
  96             return aPool;
  97         }();
  98
  99         static std::mutex aMutex;
 100
 101         std::scoped_lock g(aMutex);
 102         if (rtl_random_getBytes(pool, pTargetUUID, 16) != rtl_Random_E_None)
 103         {
 104             abort();
 105                 // only possible way to signal failure here (rtl_createUuid
 106                 // being part of a fixed C API)
 107         }
 108     }
 109     // See ITU-T Recommendation X.667:
 110     pTargetUUID[6] &= 0x0F;
 111     pTargetUUID[6] |= 0x40;
 112     pTargetUUID[8] &= 0x3F;
 113     pTargetUUID[8] |= 0x80;
 114 }
 115
 116 extern "C" void SAL_CALL rtl_createNamedUuid(sal_uInt8 *pTargetUUID,
 117                                              const sal_uInt8 *pNameSpaceUUID,
 118                                              const rtl_String *pName )
 119 {
 120     rtlDigest digest = rtl_digest_createMD5();
 121
 122     rtl_digest_updateMD5(digest, pNameSpaceUUID, 16);
 123     rtl_digest_updateMD5(digest, pName->buffer, pName->length);
 124
 125     rtl_digest_getMD5(digest, pTargetUUID, 16);
 126     rtl_digest_destroyMD5(digest);
 127
 128     write_v3(pTargetUUID);
 129 }
 130
 131 extern "C" sal_Int32 SAL_CALL rtl_compareUuid(const sal_uInt8 *pUUID1, const sal_uInt8 *pUUID2)
 132 {
 133     int i;
 134     UUID u1;
 135     UUID u2;
 136     memcpy(&u1, pUUID1, 16 );
 137     memcpy(&u2, pUUID2, 16 );
 138
 139     SWAP_NETWORK_TO_INT32(u1.time_low);
 140     SWAP_NETWORK_TO_INT16(u1.time_mid);
 141     SWAP_NETWORK_TO_INT16(u1.time_hi_and_version);
 142
 143     SWAP_NETWORK_TO_INT32(u2.time_low);
 144     SWAP_NETWORK_TO_INT16(u2.time_mid);
 145     SWAP_NETWORK_TO_INT16(u2.time_hi_and_version);
 146
 147 #define CHECK(f1, f2) if (f1 != f2) return f1 < f2 ? -1 : 1;
 148     CHECK(u1.time_low, u2.time_low);
 149     CHECK(u1.time_mid, u2.time_mid);
 150     CHECK(u1.time_hi_and_version, u2.time_hi_and_version);
 151     CHECK(u1.clock_seq_hi_and_reserved, u2.clock_seq_hi_and_reserved);
 152     CHECK(u1.clock_seq_low, u2.clock_seq_low);
 153     for (i = 0; i < 6; i++)
 154     {
 155         if (u1.node[i] < u2.node[i])
 156             return -1;
 157         if (u1.node[i] > u2.node[i])
 158             return 1;
 159     }
 160     return 0;
 161 }
 162
 163 /* vim:set shiftwidth=4 softtabstop=4 expandtab: */