digitalmars.D.learn - compile time string manipulation
- akcom (24/24) Apr 06 2007 I'm trying to change a string at compile time to avoid static analysis.
- Thomas Kuehne (26/49) Apr 07 2007 -----BEGIN PGP SIGNED MESSAGE-----
I'm trying to change a string at compile time to avoid static analysis.
Example:
T[] obfuscate(T)( T[] buf )
{
return cast(char)(buf[0] ^ 0xCC) ~ obfuscate( buf[1..$] );
}
char []unobfuscate( char []str )
{
char []result = new char[str.length];
foreach ( idx, c; str )
{
result[idx] = c ^ 0xCC;
}
return result;
}
in my code I have something like Stdout.formatln( "hello {0}",
unobfuscate( obfuscate( "world!" ) ) );
What I'd like to happen, is for obfuscate to get evaluated at compile time
so that instead of "world!" being visible in my executable's binary data, it
would be something like 0x77 0x6F 0x72 0x6C 0x64 0x21. unobfuscate would
get called at runtime and would transform the string back to it's original
form. Any ideas? (Note: I'm aware that obfuscate will throw an
ArrayOutOfBounds exception, it's just to explain what I'm trying to do).
Thanks in advance!
Apr 06 2007
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Hash: SHA1
akcom schrieb am 2007-04-07:
I'm trying to change a string at compile time to avoid static analysis.
Example:
T[] obfuscate(T)( T[] buf )
{
return cast(char)(buf[0] ^ 0xCC) ~ obfuscate( buf[1..$] );
}
char []unobfuscate( char []str )
{
char []result = new char[str.length];
foreach ( idx, c; str )
{
result[idx] = c ^ 0xCC;
}
return result;
}
in my code I have something like Stdout.formatln( "hello {0}",
unobfuscate( obfuscate( "world!" ) ) );
What I'd like to happen, is for obfuscate to get evaluated at compile time
so that instead of "world!" being visible in my executable's binary data, it
would be something like 0x77 0x6F 0x72 0x6C 0x64 0x21. unobfuscate would
get called at runtime and would transform the string back to it's original
form. Any ideas? (Note: I'm aware that obfuscate will throw an
ArrayOutOfBounds exception, it's just to explain what I'm trying to do).
Thomas
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6lXl/OqnVHLQPpCJlSNzs0o=
=eHGg
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Apr 07 2007
"akcom" <CppCoder gmail.com> Unfortunately the string still shows up in plain text in my executable. Regards, Alex "Thomas Kuehne" <thomas-dloop kuehne.cn> wrote in message news:slrnf1ekkm.cq2.thomas-dloop birke.kuehne.cn...-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 akcom schrieb am 2007-04-07:I'm trying to change a string at compile time to avoid static analysis. Example: T[] obfuscate(T)( T[] buf ) { return cast(char)(buf[0] ^ 0xCC) ~ obfuscate( buf[1..$] ); } char []unobfuscate( char []str ) { char []result = new char[str.length]; foreach ( idx, c; str ) { result[idx] = c ^ 0xCC; } return result; } in my code I have something like Stdout.formatln( "hello {0}", unobfuscate( obfuscate( "world!" ) ) ); What I'd like to happen, is for obfuscate to get evaluated at compile time so that instead of "world!" being visible in my executable's binary data, it would be something like 0x77 0x6F 0x72 0x6C 0x64 0x21. unobfuscate would get called at runtime and would transform the string back to it's original form. Any ideas? (Note: I'm aware that obfuscate will throw an ArrayOutOfBounds exception, it's just to explain what I'm trying to do).Thomas -----BEGIN PGP SIGNATURE----- iD8DBQFGF1KLLK5blCcjpWoRAlxyAJ45HvncahcYt7wsfxiJtkRw7Kfr3gCfc4bI 6lXl/OqnVHLQPpCJlSNzs0o= =eHGg -----END PGP SIGNATURE-----
Apr 07 2007
Nevermind, I made a stupid mistake. Thank you very much for your help :) "Thomas Kuehne" <thomas-dloop kuehne.cn> wrote in message news:slrnf1ekkm.cq2.thomas-dloop birke.kuehne.cn...-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 akcom schrieb am 2007-04-07:I'm trying to change a string at compile time to avoid static analysis. Example: T[] obfuscate(T)( T[] buf ) { return cast(char)(buf[0] ^ 0xCC) ~ obfuscate( buf[1..$] ); } char []unobfuscate( char []str ) { char []result = new char[str.length]; foreach ( idx, c; str ) { result[idx] = c ^ 0xCC; } return result; } in my code I have something like Stdout.formatln( "hello {0}", unobfuscate( obfuscate( "world!" ) ) ); What I'd like to happen, is for obfuscate to get evaluated at compile time so that instead of "world!" being visible in my executable's binary data, it would be something like 0x77 0x6F 0x72 0x6C 0x64 0x21. unobfuscate would get called at runtime and would transform the string back to it's original form. Any ideas? (Note: I'm aware that obfuscate will throw an ArrayOutOfBounds exception, it's just to explain what I'm trying to do).Thomas -----BEGIN PGP SIGNATURE----- iD8DBQFGF1KLLK5blCcjpWoRAlxyAJ45HvncahcYt7wsfxiJtkRw7Kfr3gCfc4bI 6lXl/OqnVHLQPpCJlSNzs0o= =eHGg -----END PGP SIGNATURE-----
Apr 07 2007