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1 /* bsd.h -- BSD disklabel data structure definitions, types, and functions */
2 
3 /* This program is copyright (c) 2009 by Roderick W. Smith. It is distributed
4   under the terms of the GNU GPL version 2, as detailed in the COPYING file. */
5 
6 #ifndef __BSD_STRUCTS
7 #define __BSD_STRUCTS
8 
9 #include <stdint.h>
10 #include <sys/types.h>
11 #include "gptpart.h"
12 #include "diskio.h"
13 
14 #define BSD_SIGNATURE UINT32_C(0x82564557)  /* BSD disklabel signature ("magic") */
15 
16 // BSD disklabels can start at offsets of 64 or the sector size -- at least,
17 // I *THINK* that's what's going on. I've seen them at 64 or 512 on disks
18 // with 512-byte blocks and at 2048 on disks with 2048-byte blocks. The
19 // LABEL_OFFSET2 value will be replaced by the block size in the
20 // ReadBSDData() function....
21 #define LABEL_OFFSET1 64
22 #define LABEL_OFFSET2 512
23 #define NUM_OFFSETS 2
24 
25 // FreeBSD documents a maximum # of partitions of 8, but I saw 16 on a NetBSD
26 // disk. I'm quadrupling that for further safety. Note that BSDReadData()
27 // uses a 4096-byte I/O buffer. In combination with LABEL_OFFSET3 and the
28 // additional 148-byte offset to the actual partition data, that gives a
29 // theoretical maximum of 118.75 partitions that the program can handle before
30 // memory errors will occur.
31 #define MAX_BSD_PARTS 64
32 
33 /****************************************
34  *                                      *
35  * BSDData class and related structures *
36  *                                      *
37  ****************************************/
38 
39 // Possible states of the MBR
40 enum BSDValidity {unknown, bsd_invalid, bsd};
41 
42 // Data for a single BSD partition record
43 // Create entries for all fields, although we only use lengthLBA, firstLBA,
44 // and fsType, to simplify loading the data from disk....
45 struct  BSDRecord {      // the partition table
46    uint32_t lengthLBA;   // number of sectors in partition
47    uint32_t firstLBA;    // starting sector
48    uint32_t fragSize;    // filesystem basic fragment size
49    uint8_t  fsType;      // filesystem type, see below
50    uint8_t  frag;        // filesystem fragments per block
51    uint16_t pcpg;        // filesystem cylinders per group
52 };
53 
54 // Full data in tweaked BSD format
55 // For some reason this has to be packed or MS Visual C++'s debugger complains
56 // about memory errors whenever a BSDData variable is destroyed.
57 #pragma pack (8)
58 class BSDData {
59    protected:
60       // We only need a few items from the main BSD disklabel data structure....
61       uint32_t signature;        // the magic number
62       uint32_t sectorSize;       // # of bytes per sector
63       uint32_t signature2;       // the magic number (again)
64       uint16_t numParts;         // number of partitions in table
65       struct BSDRecord* partitions;     // partition array
66 
67       // Above are basic BSD disklabel data; now add more stuff....
68       uint64_t labelFirstLBA;    // first sector of BSD disklabel (partition or disk)
69       uint64_t labelLastLBA;     // final sector of BSD disklabel
70       uint64_t labelStart;       // BSD disklabel start point in bytes from labelFirstLBA
71       BSDValidity state;
72    public:
73       BSDData(void);
74       ~BSDData(void);
75       int ReadBSDData(const std::string & deviceFilename, uint64_t startSector, uint64_t endSector);
76       int ReadBSDData(DiskIO *myDisk, uint64_t startSector, uint64_t endSector);
77       void ReverseMetaBytes(void);
78       void DisplayBSDData(void);
79       int ShowState(void); // returns 1 if BSD disklabel detected
80       int IsDisklabel(void);
81 
82       // Functions to extract data on specific partitions....
83       uint8_t GetType(int i);
84       uint64_t GetFirstSector(int i);
85       uint64_t GetLength(int i);
86       int GetNumParts(void);
87       GPTPart AsGPT(int i); // Return BSD part. as GPT part.
88 }; // struct MBRData
89 #pragma pack ()
90 
91 #endif
92