llSHA256String

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Summary

Function: string llSHA256String( string src );
0.0 Forced Delay
10.0 Energy

Returns a string of 64 hex characters that is the "Wikipedia logo"SHA-256 security hash of src.

• string src

Specification

LSL strings are stored in the UTF-8 format.

Caveats

There's no way to input a zero-byte value into this function, nor any byte value from 128-255, therefore it's currently broken for many purposes (like HMAC-SHA1). The reason is because LSL strings cannot have a unicode null character (U+0000) in them, and LSL has no escape code for the null character (many programming languages use \0 but LSL does not have this feature). llEscapeURL("%00") yields an empty string. As well, inside this function, each character with a Unicode integer value over U+0127 / 007F are dealt with in UTF-8 fashion: in the hex values, 0xC2 is prepended to the byte value (hence 0x0080-0x00FF become 0xC280-0xC2FF inside the llSHA256String() routine).

Examples

llSay(0, llSHA256String("Hello, Avatar!")); // returns 3a9f9d2e4360319a62139d19bd425c16fb8439b832d74d5221ca75b54c35b4f2

Linux Example

$ echo -n 'Hello, Avatar!' | openssl sha256
3a9f9d2e4360319a62139d19bd425c16fb8439b832d74d5221ca75b54c35b4f2

See Also

Functions

•  llMD5String
•  llSHA1String

Articles

•  SHA-2

Deep Notes

Prior to this, the only way to get the SHA-256 hash was to use the LSL SHA-256 port: SHA-2

Signature

function string llSHA256String( string src );