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Diffstat (limited to 'unzcrash.cc')
| -rw-r--r-- | unzcrash.cc | 355 |
1 files changed, 355 insertions, 0 deletions
diff --git a/unzcrash.cc b/unzcrash.cc new file mode 100644 index 0000000..0b44997 --- /dev/null +++ b/unzcrash.cc @@ -0,0 +1,355 @@ +/* Unzcrash - Tests robustness of decompressors to corrupted data. + Inspired by unzcrash.c from Julian Seward's bzip2. + Copyright (C) 2008-2014 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 + the Free Software Foundation, either version 2 of the License, or + (at your option) any later version. + + This program is distributed in the hope that it will be useful, + but WITHOUT ANY WARRANTY; without even the implied warranty of + MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + GNU General Public License for more details. + + You should have received a copy of the GNU General Public License + along with this program. If not, see <http://www.gnu.org/licenses/>. +*/ +/* + Exit status: 0 for a normal exit, 1 for environmental problems + (file not found, invalid flags, I/O errors, etc), 2 to indicate a + corrupt or invalid input file, 3 for an internal consistency error + (eg, bug) which caused unzcrash to panic. +*/ + +#include <cerrno> +#include <climits> +#include <csignal> +#include <cstdio> +#include <cstdlib> +#include <cstring> +#include <string> +#include <vector> +#include <stdint.h> +#include <unistd.h> + +#include "arg_parser.h" + +#if CHAR_BIT != 8 +#error "Environments where CHAR_BIT != 8 are not supported." +#endif + + +namespace { + +const char * const Program_name = "Unzcrash"; +const char * const program_name = "unzcrash"; +const char * const program_year = "2014"; +const char * invocation_name = 0; + +int verbosity = 0; + + +void show_help() + { + std::printf( "%s - Tests robustness of decompressors to corrupted data.\n", Program_name ); + std::printf( "\nUsage: %s [options] \"lzip -tv\" filename.lz\n", invocation_name ); + std::printf( "\nThis program reads the specified file and then repeatedly decompresses\n" + "it, increasing 256 times each byte of the compressed data, so as to test\n" + "all possible one-byte errors. This should not cause any invalid memory\n" + "accesses. If it does, please, report it as a bug.\n" + "\nOptions:\n" + " -h, --help display this help and exit\n" + " -V, --version output version information and exit\n" + " -b, --bits=<range> test N-bit errors instead of full byte\n" + " -p, --position=<bytes> first byte position to test [default 0]\n" + " -q, --quiet suppress all messages\n" + " -s, --size=<bytes> number of byte positions to test [all]\n" + " -v, --verbose be verbose (a 2nd -v gives more)\n" + "Examples of <range>: 1 1,2,3 1-4 1,3-5,8 1-3,5-8\n" + "\nExit status: 0 for a normal exit, 1 for environmental problems (file\n" + "not found, invalid flags, I/O errors, etc), 2 to indicate a corrupt or\n" + "invalid input file, 3 for an internal consistency error (eg, bug) which\n" + "caused unzcrash to panic.\n" + "\nReport bugs to lzip-bug@nongnu.org\n" + "Lziprecover home page: http://www.nongnu.org/lzip/lziprecover.html\n" ); + } + + +void show_version() + { + std::printf( "%s %s\n", program_name, PROGVERSION ); + std::printf( "Copyright (C) %s Antonio Diaz Diaz.\n", program_year ); + std::printf( "License GPLv2+: GNU GPL version 2 or later <http://gnu.org/licenses/gpl.html>\n" + "This is free software: you are free to change and redistribute it.\n" + "There is NO WARRANTY, to the extent permitted by law.\n" ); + } + + +void show_error( const char * const msg, const int errcode = 0, + const bool help = false ) + { + if( verbosity >= 0 ) + { + if( msg && msg[0] ) + { + std::fprintf( stderr, "%s: %s", program_name, msg ); + if( errcode > 0 ) + std::fprintf( stderr, ": %s", std::strerror( errcode ) ); + std::fprintf( stderr, "\n" ); + } + if( help ) + std::fprintf( stderr, "Try '%s --help' for more information.\n", + invocation_name ); + } + } + + +void internal_error( const char * const msg ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "%s: internal error: %s\n", program_name, msg ); + std::exit( 3 ); + } + + +unsigned long long getnum( const char * const ptr, + const unsigned long long llimit, + const unsigned long long ulimit ) + { + char * tail; + errno = 0; + unsigned long long result = strtoull( ptr, &tail, 0 ); + if( tail == ptr ) + { + show_error( "Bad or missing numerical argument.", 0, true ); + std::exit( 1 ); + } + + if( !errno && tail[0] ) + { + int factor = ( tail[1] == 'i' ) ? 1024 : 1000; + int exponent = 0; + bool bad_multiplier = false; + switch( tail[0] ) + { + case ' ': break; + case 'Y': exponent = 8; break; + case 'Z': exponent = 7; break; + case 'E': exponent = 6; break; + case 'P': exponent = 5; break; + case 'T': exponent = 4; break; + case 'G': exponent = 3; break; + case 'M': exponent = 2; break; + case 'K': if( factor == 1024 ) exponent = 1; else bad_multiplier = true; + break; + case 'k': if( factor == 1000 ) exponent = 1; else bad_multiplier = true; + break; + default : bad_multiplier = true; + } + if( bad_multiplier ) + { + show_error( "Bad multiplier in numerical argument.", 0, true ); + std::exit( 1 ); + } + for( int i = 0; i < exponent; ++i ) + { + if( ulimit / factor >= result ) result *= factor; + else { errno = ERANGE; break; } + } + } + if( !errno && ( result < llimit || result > ulimit ) ) errno = ERANGE; + if( errno ) + { + show_error( "Numerical argument out of limits." ); + std::exit( 1 ); + } + return result; + } + + +class Bitset8 // 8 value bitset (1 to 8) + { + bool data[8]; + static bool valid_digit( const unsigned char ch ) + { return ( ch >= '1' && ch <= '8' ); } + +public: + Bitset8() { for( int i = 0; i < 8; ++i ) data[i] = true; } + + bool includes( const int i ) const + { return ( i >= 1 && i <= 8 && data[i-1] ); } + + // Recognized formats: 1 1,2,3 1-4 1,3-5,8 1-3,5-8 + bool parse( const char * p ) + { + for( int i = 0; i < 8; ++i ) data[i] = false; + while( true ) + { + const unsigned char ch1 = *p++; + if( !valid_digit( ch1 ) ) break; + if( *p != '-' ) data[ch1-'1'] = true; + else + { + ++p; + if( !valid_digit( *p ) || ch1 > *p ) break; + for( int c = ch1; c <= *p; ++c ) data[c-'1'] = true; + ++p; + } + if( *p == 0 ) return true; + if( *p == ',' ) ++p; else break; + } + show_error( "Invalid value or range." ); + return false; + } + + // number of N-bit errors per byte (N=0 to 8): 1 8 28 56 70 56 28 8 1 + void print() const + { + std::fflush( stderr ); + int c = 0; + for( int i = 0; i < 8; ++i ) if( data[i] ) ++c; + if( c == 8 ) std::fputs( "Testing full byte.\n", stdout ); + else if( c == 0 ) std::fputs( "Nothing to test.\n", stdout ); + else + { + std::fputs( "Testing ", stdout ); + for( int i = 0; i < 8; ++i ) + if( data[i] ) + { + std::printf( "%d", i + 1 ); + if( --c ) std::fputs( ",", stdout ); + } + std::fputs( " bit errors.\n", stdout ); + } + std::fflush( stdout ); + } + }; + + +int differing_bits( const uint8_t byte1, const uint8_t byte2 ) + { + int count = 0; + uint8_t dif = byte1 ^ byte2; + while( dif ) + { count += ( dif & 1 ); dif >>= 1; } + return count; + } + +} // end namespace + + +int main( const int argc, const char * const argv[] ) + { + enum { buffer_size = 75 << 20 }; + Bitset8 bits; // if Bitset8::parse not called test full byte + int pos = 0; + int max_size = buffer_size; + invocation_name = argv[0]; + + const Arg_parser::Option options[] = + { + { 'h', "help", Arg_parser::no }, + { 'b', "bits", Arg_parser::yes }, + { 'p', "position", Arg_parser::yes }, + { 'q', "quiet", Arg_parser::no }, + { 's', "size", Arg_parser::yes }, + { 'v', "verbose", Arg_parser::no }, + { 'V', "version", Arg_parser::no }, + { 0 , 0, Arg_parser::no } }; + + const Arg_parser parser( argc, argv, options ); + if( parser.error().size() ) // bad option + { show_error( parser.error().c_str(), 0, true ); return 1; } + + int argind = 0; + for( ; argind < parser.arguments(); ++argind ) + { + const int code = parser.code( argind ); + if( !code ) break; // no more options + const char * const arg = parser.argument( argind ).c_str(); + switch( code ) + { + case 'h': show_help(); return 0; + case 'b': if( !bits.parse( arg ) ) return 1; break; + case 'p': pos = getnum( arg, 0, buffer_size - 1 ); break; + case 'q': verbosity = -1; break; + case 's': max_size = getnum( arg, 1, buffer_size ); break; + case 'v': if( verbosity < 4 ) ++verbosity; break; + case 'V': show_version(); return 0; + default : internal_error( "uncaught option." ); + } + } // end process options + + if( argind + 2 != parser.arguments() ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "Usage: %s \"lzip -tv\" filename.lz\n", + invocation_name ); + return 1; + } + + FILE *f = std::fopen( parser.argument( argind + 1 ).c_str(), "rb" ); + if( !f ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "Can't open file '%s' for reading\n", + parser.argument( argind + 1 ).c_str() ); + return 1; + } + + uint8_t * const buffer = new uint8_t[buffer_size]; + const int size = std::fread( buffer, 1, buffer_size, f ); + if( size >= buffer_size ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "input file '%s' is too large.\n", + parser.argument( argind + 1 ).c_str() ); + return 2; + } + std::fclose( f ); + + f = popen( parser.argument( argind ).c_str(), "w" ); + if( !f ) + { show_error( "Can't open pipe", errno ); return 1; } + const int wr = std::fwrite( buffer, 1, size, f ); + if( wr != size || pclose( f ) != 0 ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "Could not run '%s' : %s.\n", + parser.argument( argind ).c_str(), std::strerror( errno ) ); + return 1; + } + + std::signal( SIGPIPE, SIG_IGN ); + if( verbosity >= 1 ) bits.print(); + + const int end = ( ( pos + max_size < size ) ? pos + max_size : size ); + for( int i = pos; i < end; ++i ) + { + if( verbosity >= 0 ) + std::fprintf( stderr, "byte %d\n", i ); + const uint8_t byte = buffer[i]; + for( int j = 1; j < 256; ++j ) + { + ++buffer[i]; + if( bits.includes( differing_bits( byte, buffer[i] ) ) ) + { + if( verbosity >= 2 ) + std::fprintf( stderr, "0x%02X (0x%02X+0x%02X) ", + buffer[i], byte, j ); + f = popen( parser.argument( argind ).c_str(), "w" ); + if( !f ) + { show_error( "Can't open pipe", errno ); return 1; } + std::fwrite( buffer, 1, size, f ); + if( pclose( f ) == 0 && verbosity >= 0 ) + std::fprintf( stderr, "0x%02X (0x%02X+0x%02X) passed the test\n", + buffer[i], byte, j ); + } + } + buffer[i] = byte; + } + + delete[] buffer; + return 0; + } |