Аналіз загрузщіка BIOS та MBR

Лабораторна робота №4

Аналіз загрузщіка BIOS та MBR.

1. Мета роботи: проаналізувати загрузщики BIOS та MBR.
2. Лістінги:

MBR:

-u 6000:7c00 7c8a

6000:7C00 FA            CLI                                             

6000:7C01 33C0          XOR       AX,AX                              

6000:7C03 8ED0          MOV      SS,AX                             

6000:7C05 BC007C        MOV   SP,7C00                           

6000:7C08 8BF4          MOV      SI,SP                             

6000:7C0A 50            PUSH       AX                                 

6000:7C0B 07            POP          ES                                

6000:7C0C 50            PUSH        AX                                

6000:7C0D 1F            POP          DS                                

6000:7C0E FB            STI                                              

6000:7C0F FC            CLD                                           

6000:7C10 BF0006        MOV    DI,0600                           

6000:7C13 B90001        MOV    CX,0100                           

6000:7C16 F2            REPNZ                                         

6000:7C17 A5            MOVSW                                    

6000:7C18 EA1D060000    JMP 0000:061D                         

6000:7C1D BEBE07        MOV  SI,07BE                           

6000:7C20 B304          MOV      BL,04                              

6000:7C22 803C80        CMP     BYTE PTR [SI],80                  

6000:7C25 740E          JZ            7C35                              

6000:7C27 803C00        CMP     BYTE PTR [SI],00                  

6000:7C2A 751C          JNZ        7C48                               

6000:7C2C 83C610        ADD     SI,+10                            

6000:7C2F FECB          DEC      BL                                

6000:7C31 75EF          JNZ         7C22                              

6000:7C33 CD18          INT        18                                 

6000:7C35 8B14          MOV      DX,[SI]                           

6000:7C37 8B4C02        MOV    CX,[SI+02]                        

6000:7C3A 8BEE          MOV     BP,SI                             

6000:7C3C 83C610        ADD     SI,+10                             

6000:7C3F FECB          DEC      BL                                

6000:7C41 741A          JZ           7C5D                              

6000:7C43 803C00        CMP     BYTE PTR [SI],00                  

6000:7C46 74F4          JZ            7C3C                               

6000:7C48 BE8B06        MOV   SI,068B                           

6000:7C4B AC            LODSB                                     

6000:7C4C 3C00          CMP       AL,00                             

6000:7C4E 740B          JZ           7C5B                               

6000:7C50 56            PUSH        SI                                

6000:7C51 BB0700        MOV    BX,0007                           

6000:7C54 B40E          MOV      AH,0E                             

6000:7C56 CD10          INT        10                                 

6000:7C58 5E            POP           SI                                

6000:7C59 EBF0          JMP        7C4B                              

6000:7C5B EBFE          JMP       7C5B                              

6000:7C5D BF0500        MOV   DI,0005                            

6000:7C60 BB007C        MOV   BX,7C00                           

6000:7C63 B80102        MOV    AX,0201                           

6000:7C66 57            PUSH        DI                                

6000:7C67 CD13          INT        13                                 

6000:7C69 5F            POP           DI                                

6000:7C6A 730C          JNB        7C78                              

6000:7C6C 33C0          XOR       AX,AX                             

6000:7C6E CD13          INT        13                                 

6000:7C70 4F            DEC          DI                                

6000:7C71 75ED          JNZ        7C60                              

6000:7C73 BEA306        MOV   SI,06A3                           

6000:7C76 EBD3          JMP       7C4B                               

6000:7C78 BEC206        MOV   SI,06C2                           

6000:7C7B BFFE7D        MOV  DI,7DFE                           

6000:7C7E 813D55AA      CMP WORD PTR [DI],AA55                

6000:7C82 75C7          JNZ         7C4B                               

6000:7C84 8BF5          MOV      SI,BP                             

6000:7C86 EA007C0000    JMP 0000:7C00                         

-

-

-

-d 6000:7c8a 7dff

6000:7C80                                00 49 6E 76 61 6C             .Inval

6000:7C90  69 64 20 70 61 72 74 69-74 69 6F 6E 20 74 61 62   id partition tab

6000:7CA0  6C 65 00 45 72 72 6F 72-20 6C 6F 61 64 69 6E 67   le.Error loading

6000:7CB0  20 6F 70 65 72 61 74 69-6E 67 20 73 79 73 74 65    operating syste

6000:7CC0  6D 00 4D 69 73 73 69 6E-67 20 6F 70 65 72 61 74   m.Missing operat

6000:7CD0  69 6E 67 20 73 79 73 74-65 6D 00 00 00 00 00 00   ing system......

6000:7CE0  00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00   ................

6000:7CF0  00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00   ................

6000:7D00  00 00 00 00 00 00 00 00-00 00 00 00 00 00 00 00   ................