VtoyTool/BabyISO/biso_eltorito.c

   1 /******************************************************************************
   2  * bios_eltorito.c
   3  *
   4  * Copyright (c) 2020, longpanda <admin@ventoy.net>
   5  *
   6  * This program is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU General Public License as
   8  * published by the Free Software Foundation; either version 3 of the
   9  * License, or (at your option) any later version.
  10  *
  11  * This program is distributed in the hope that it will be useful, but
  12  * WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * General Public License for more details.
  15  *
  16  * You should have received a copy of the GNU General Public License
  17  * along with this program; if not, see <http://www.gnu.org/licenses/>.
  18  *
  19  */
  20
  21 #include "biso.h"
  22 #include "biso_list.h"
  23 #include "biso_util.h"
  24 #include "biso_9660.h"
  25 #include "biso_eltorito.h"
  26
  27 ULONG BISO_ELTORITO_ReadBootInfo
  28 (
  29     IN  BISO_FILE_S   *pstFile,
  30     OUT BISO_PARSER_S *pstParser
  31 )
  32 {
  33     USHORT i;
  34     UINT uiReadLen = 0;
  35     UINT64 ui64Seek = 0;
  36     UCHAR aucBuf[BISO_SECTOR_SIZE];
  37     BISO_MBUF_S stMBuf;
  38     BISO_TORITO_SECHDR_ENTRY_S *pstSecHdr = NULL;
  39     BISO_TORITO_SECTION_ENTRY_S *pstSection = NULL;
  40
  41     DBGASSERT(NULL != pstFile);
  42     DBGASSERT(NULL != pstParser);
  43
  44     if (NULL == pstParser->pstBVD)
  45     {
  46         return BISO_SUCCESS;
  47     }
  48
  49     memset(&stMBuf, 0, sizeof(stMBuf));
  50     ui64Seek = (UINT64)pstParser->pstBVD->uiBootCatlogStart * BISO_SECTOR_SIZE;
  51     BISO_PLAT_SeekFile(pstFile, ui64Seek, SEEK_SET);
  52
  53     /* 先读取1个逻辑扇区的内容 */
  54     uiReadLen = (UINT)BISO_PLAT_ReadFile(pstFile, 1, BISO_SECTOR_SIZE, aucBuf);
  55     if (uiReadLen != BISO_SECTOR_SIZE)
  56     {
  57         BISO_DIAG("Read len %u buf len %u.", uiReadLen, BISO_SECTOR_SIZE);
  58         return BISO_ERR_READ_FILE;
  59     }
  60
  61     /* 前两条Entry固定是Validation和Initial */
  62     pstSecHdr = (BISO_TORITO_SECHDR_ENTRY_S *)(aucBuf + 2 * BISO_ELTORITO_ENTRY_LEN);
  63     pstSection = (BISO_TORITO_SECTION_ENTRY_S *)pstSecHdr;
  64
  65     while ((0x90 == pstSecHdr->ucFlag) || (0x91 == pstSecHdr->ucFlag))
  66     {
  67         pstSecHdr = (BISO_TORITO_SECHDR_ENTRY_S *)pstSection;
  68         BISO_ELTORITO_ENTRY_STEP(pstSection, pstFile, aucBuf, stMBuf);
  69
  70         for (i = 0; i < pstSecHdr->usSecEntryNum; )
  71         {
  72             /*
  73              * Section Entry和Extension Entry都是由ucFlag的Bit5决定是否结束
  74              * 因此这里全部都用Section Entry的结构做判断
  75              */
  76             if (0 == (pstSection->ucFlag & 0x10))
  77             {
  78                 i++;
  79             }
  80
  81             BISO_ELTORITO_ENTRY_STEP(pstSection, pstFile, aucBuf, stMBuf);
  82         }
  83
  84         if (0x91 == pstSecHdr->ucFlag) /* 91代表最后一个 */
  85         {
  86             break;
  87         }
  88     }
  89
  90     if ((UCHAR *)pstSection > aucBuf)
  91     {
  92         (VOID)BISO_MBUF_Append(&stMBuf, (UCHAR *)pstSection - aucBuf, aucBuf);
  93     }
  94
  95     /* 保存到全局结构中 */
  96     pstParser->uiElToritoLen = stMBuf.uiTotDataSize;
  97     pstParser->pucElToritoEntry = (UCHAR *)BISO_MALLOC(pstParser->uiElToritoLen);
  98     if (NULL == pstParser->pucElToritoEntry)
  99     {
 100         BISO_MBUF_Free(&stMBuf);
 101         return BISO_ERR_ALLOC_MEM;
 102     }
 103
 104     BISO_MBUF_CopyToBuf(&stMBuf, pstParser->pucElToritoEntry);
 105     BISO_MBUF_Free(&stMBuf);
 106     return  BISO_SUCCESS;
 107 }
 108
 109 VOID BISO_ELTORITO_Dump(IN CONST BISO_PARSER_S *pstParser)
 110 {
 111     BISO_DUMP("uiElToritoLen=%u\n", pstParser->uiElToritoLen);
 112 }
 113
 114
 115 UINT BISO_ELTORITO_GetBootEntryNum(IN CONST BISO_PARSER_S *pstParser)
 116 {
 117     UINT uiRet = 0;
 118     UINT uiEntryNum = 0;
 119     UCHAR *pucData = NULL;
 120     BISO_TORITO_VALIDATION_ENTRY_S *pstValidation = NULL;
 121     BISO_TORITO_INITIAL_ENTRY_S *pstInitial = NULL;
 122
 123     if (NULL == pstParser->pucElToritoEntry)
 124     {
 125         return 0;
 126     }
 127
 128     uiEntryNum = pstParser->uiElToritoLen / BISO_ELTORITO_ENTRY_LEN;
 129     pstValidation = (BISO_TORITO_VALIDATION_ENTRY_S *)pstParser->pucElToritoEntry;
 130     pstInitial = (BISO_TORITO_INITIAL_ENTRY_S *)(pstValidation + 1);
 131
 132     if (pstInitial->ucBootId == 0x88)
 133     {
 134         uiRet++;
 135     }
 136
 137     pucData = pstParser->pucElToritoEntry + 2 * BISO_ELTORITO_ENTRY_LEN;
 138     uiEntryNum-= 2;
 139
 140     while (uiEntryNum > 0)
 141     {
 142         if ((0x90 == pucData[0]) || (0x91 == pucData[0]))
 143         {
 144         }
 145         else if (0x44 == pucData[0])
 146         {
 147         }
 148         else
 149         {
 150             if (((BISO_TORITO_SECTION_ENTRY_S *)pucData)->ucBootId == 0x88)
 151             {
 152                 uiRet++;
 153             }
 154         }
 155         pucData += BISO_ELTORITO_ENTRY_LEN;
 156         uiEntryNum--;
 157     }
 158
 159     return uiRet;
 160 }
 161