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21
22
23
24 // MARKER(update_precomp.py): autogen include statement, do not remove
25 #include "precompiled_tools.hxx"
26
27 #include "md5.hxx"
28
29 #include <cstddef>
30 #include <stdio.h>
31
32 #include <tools/string.hxx>
33
34 #ifdef WNT
35 #define FILE_OPEN_READ "rb"
36 #else
37 #define FILE_OPEN_READ "r"
38 #endif
39
40 // Extended calc_md5_checksum to recognize Windows executables and libraries. To
41 // create the same md5 checksum for a (code/data) identical file it ignores a different
42 // date and header checksum. Please see crashrep/source/win32/soreport.cpp
43 // where the same method is also used. The crash reporter uses the MD5
44 // checksums to transfer them to the crash database. You have to make sure that both
45 // methods use the same algorithm otherwise there could be problems with stack reports.
46
normalize_pe_image(sal_uInt8 * buffer,size_t nBufferSize)47 void normalize_pe_image(sal_uInt8* buffer, size_t nBufferSize)
48 {
49 const int OFFSET_PE_OFFSET = 0x3c;
50 const int OFFSET_COFF_TIMEDATESTAMP = 4;
51 const int PE_SIGNATURE_SIZE = 4;
52 const int COFFHEADER_SIZE = 20;
53 const int OFFSET_PE_OPTIONALHEADER_CHECKSUM = 64;
54
55 // Check the header part of the file buffer
56 if (buffer[0] == sal_uInt8('M') && buffer[1] == sal_uInt8('Z'))
57 {
58 unsigned long PEHeaderOffset = (long)buffer[OFFSET_PE_OFFSET];
59 if (PEHeaderOffset < nBufferSize-4)
60 {
61 if ( buffer[PEHeaderOffset+0] == sal_uInt8('P') &&
62 buffer[PEHeaderOffset+1] == sal_uInt8('E') &&
63 buffer[PEHeaderOffset+2] == 0 &&
64 buffer[PEHeaderOffset+3] == 0 )
65 {
66 PEHeaderOffset += PE_SIGNATURE_SIZE;
67 if (PEHeaderOffset+OFFSET_COFF_TIMEDATESTAMP < nBufferSize-4)
68 {
69 // Set timedatestamp and checksum fields to a normalized
70 // value to enforce the same MD5 checksum for identical
71 // Windows executables/libraries.
72 buffer[PEHeaderOffset+OFFSET_COFF_TIMEDATESTAMP+0] = 0;
73 buffer[PEHeaderOffset+OFFSET_COFF_TIMEDATESTAMP+1] = 0;
74 buffer[PEHeaderOffset+OFFSET_COFF_TIMEDATESTAMP+2] = 0;
75 buffer[PEHeaderOffset+OFFSET_COFF_TIMEDATESTAMP+3] = 0;
76 }
77
78 if (PEHeaderOffset+COFFHEADER_SIZE+OFFSET_PE_OPTIONALHEADER_CHECKSUM < nBufferSize-4)
79 {
80 // Set checksum to a normalized value
81 buffer[PEHeaderOffset+COFFHEADER_SIZE+OFFSET_PE_OPTIONALHEADER_CHECKSUM] = 0;
82 buffer[PEHeaderOffset+COFFHEADER_SIZE+OFFSET_PE_OPTIONALHEADER_CHECKSUM+1] = 0;
83 buffer[PEHeaderOffset+COFFHEADER_SIZE+OFFSET_PE_OPTIONALHEADER_CHECKSUM+2] = 0;
84 buffer[PEHeaderOffset+COFFHEADER_SIZE+OFFSET_PE_OPTIONALHEADER_CHECKSUM+3] = 0;
85 }
86 }
87 }
88 }
89 }
90
calc_md5_checksum(const char * filename,ByteString & aChecksum)91 rtlDigestError calc_md5_checksum( const char *filename, ByteString &aChecksum )
92 {
93 const size_t BUFFER_SIZE = 0x1000;
94 const size_t MINIMAL_SIZE = 512;
95
96 sal_uInt8 checksum[RTL_DIGEST_LENGTH_MD5];
97 rtlDigestError error = rtl_Digest_E_None;
98
99 FILE *fp = fopen( filename, FILE_OPEN_READ );
100
101 if ( fp )
102 {
103 rtlDigest digest = rtl_digest_createMD5();
104
105 if ( digest )
106 {
107 size_t nBytesRead;
108 sal_uInt8 buffer[BUFFER_SIZE];
109 bool bHeader(true);
110
111 while ( rtl_Digest_E_None == error &&
112 0 != (nBytesRead = fread( buffer, 1, sizeof(buffer), fp )) )
113 {
114 if (bHeader)
115 {
116 bHeader = false;
117 if (nBytesRead >= MINIMAL_SIZE && buffer[0] == sal_uInt8('M') && buffer[1] == sal_uInt8('Z') )
118 normalize_pe_image(buffer, nBytesRead);
119 }
120
121 error = rtl_digest_updateMD5( digest, buffer, nBytesRead );
122 }
123
124 if ( rtl_Digest_E_None == error )
125 {
126 error = rtl_digest_getMD5( digest, checksum, sizeof(checksum) );
127 }
128
129 rtl_digest_destroyMD5( digest );
130
131 for ( std::size_t i = 0; i < sizeof(checksum); i++ )
132 {
133 if ( checksum[i] < 16 )
134 aChecksum.Append( "0" );
135 aChecksum += ByteString::CreateFromInt32( checksum[i], 16 );
136 }
137 }
138
139 fclose( fp );
140 }
141 else
142 error = rtl_Digest_E_Unknown;
143
144 return error;
145 }
146