diff options
Diffstat (limited to 'lzip.h')
| -rw-r--r-- | lzip.h | 56 |
1 files changed, 35 insertions, 21 deletions
@@ -1,5 +1,5 @@ /* Lunzip - Decompressor for the lzip format - Copyright (C) 2010-2018 Antonio Diaz Diaz. + Copyright (C) 2010-2019 Antonio Diaz Diaz. This program is free software: you can redistribute it and/or modify it under the terms of the GNU General Public License as published by @@ -119,7 +119,7 @@ static inline void Lm_init( struct Len_model * const lm ) /* defined in main.c */ extern int verbosity; -struct Pretty_print +struct Pretty_print /* requires global var 'int verbosity' */ { const char * name; char * padded_name; @@ -146,7 +146,7 @@ static inline void Pp_init( struct Pretty_print * const pp, { const char * const s = filenames[i]; const unsigned len = (strcmp( s, "-" ) == 0) ? stdin_name_len : strlen( s ); - if( len > pp->longest_name ) pp->longest_name = len; + if( pp->longest_name < len ) pp->longest_name = len; } if( pp->longest_name == 0 ) pp->longest_name = stdin_name_len; } @@ -209,40 +209,40 @@ static inline bool isvalid_ds( const unsigned dictionary_size ) dictionary_size <= max_dictionary_size ); } -static const uint8_t magic_string[4] = { 0x4C, 0x5A, 0x49, 0x50 }; /* "LZIP" */ +static const uint8_t lzip_magic[4] = { 0x4C, 0x5A, 0x49, 0x50 }; /* "LZIP" */ -typedef uint8_t File_header[6]; /* 0-3 magic bytes */ +typedef uint8_t Lzip_header[6]; /* 0-3 magic bytes */ /* 4 version */ /* 5 coded_dict_size */ -enum { Fh_size = 6 }; +enum { Lh_size = 6 }; -static inline bool Fh_verify_magic( const File_header data ) - { return ( memcmp( data, magic_string, 4 ) == 0 ); } +static inline bool Lh_verify_magic( const Lzip_header data ) + { return ( memcmp( data, lzip_magic, 4 ) == 0 ); } /* detect (truncated) header */ -static inline bool Fh_verify_prefix( const File_header data, const int sz ) +static inline bool Lh_verify_prefix( const Lzip_header data, const int sz ) { int i; for( i = 0; i < sz && i < 4; ++i ) - if( data[i] != magic_string[i] ) return false; + if( data[i] != lzip_magic[i] ) return false; return ( sz > 0 ); } /* detect corrupt header */ -static inline bool Fh_verify_corrupt( const File_header data ) +static inline bool Lh_verify_corrupt( const Lzip_header data ) { int matches = 0; int i; for( i = 0; i < 4; ++i ) - if( data[i] == magic_string[i] ) ++matches; + if( data[i] == lzip_magic[i] ) ++matches; return ( matches > 1 && matches < 4 ); } -static inline uint8_t Fh_version( const File_header data ) +static inline uint8_t Lh_version( const Lzip_header data ) { return data[4]; } -static inline bool Fh_verify_version( const File_header data ) +static inline bool Lh_verify_version( const Lzip_header data ) { return ( data[4] == 1 ); } -static inline unsigned Fh_get_dictionary_size( const File_header data ) +static inline unsigned Lh_get_dictionary_size( const Lzip_header data ) { unsigned sz = ( 1 << ( data[5] & 0x1F ) ); if( sz > min_dictionary_size ) @@ -251,34 +251,48 @@ static inline unsigned Fh_get_dictionary_size( const File_header data ) } -typedef uint8_t File_trailer[20]; +typedef uint8_t Lzip_trailer[20]; /* 0-3 CRC32 of the uncompressed data */ /* 4-11 size of the uncompressed data */ /* 12-19 member size including header and trailer */ +enum { Lt_size = 20 }; -enum { Ft_size = 20 }; - -static inline unsigned Ft_get_data_crc( const File_trailer data ) +static inline unsigned Lt_get_data_crc( const Lzip_trailer data ) { unsigned tmp = 0; int i; for( i = 3; i >= 0; --i ) { tmp <<= 8; tmp += data[i]; } return tmp; } -static inline unsigned long long Ft_get_data_size( const File_trailer data ) +static inline unsigned long long Lt_get_data_size( const Lzip_trailer data ) { unsigned long long tmp = 0; int i; for( i = 11; i >= 4; --i ) { tmp <<= 8; tmp += data[i]; } return tmp; } -static inline unsigned long long Ft_get_member_size( const File_trailer data ) +static inline unsigned long long Lt_get_member_size( const Lzip_trailer data ) { unsigned long long tmp = 0; int i; for( i = 19; i >= 12; --i ) { tmp <<= 8; tmp += data[i]; } return tmp; } +/* check internal consistency */ +static inline bool Lt_verify_consistency( const Lzip_trailer data ) + { + const unsigned crc = Lt_get_data_crc( data ); + const unsigned long long dsize = Lt_get_data_size( data ); + const unsigned long long msize = Lt_get_member_size( data ); + const unsigned long long mlimit = ( 9 * dsize + 7 ) / 8 + min_member_size; + const unsigned long long dlimit = 7090 * ( msize - 26 ) - 1; + if( ( crc == 0 ) != ( dsize == 0 ) ) return false; + if( msize < min_member_size ) return false; + if( mlimit > dsize && msize > mlimit ) return false; + if( dlimit > msize && dsize > dlimit ) return false; + return true; + } + static const char * const bad_magic_msg = "Bad magic number (file not in lzip format)."; static const char * const bad_dict_msg = "Invalid dictionary size in member header."; |