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String.getBytes() and getBytes(charset) both encoded UTF-16LE regardless
of the requested charset. Java's default on Android is UTF-8, and
getBytes("UTF-8") is the common case in the obfuscated string/crypto code
this VM is used to analyse. Encoding UTF-16LE returned twice as many
bytes, so every downstream digest, cipher, or Base64 over the result was
wrong.
Honour the charset argument when present and default to UTF-8; keep the
surrogatepass handling. Example: "hi".getBytes("UTF-8") now yields
[0x68,0x69] instead of [0x68,0x00,0x69,0x00].
Co-Authored-By: Martin Monperrus (AI-assisted) <martin.monperrus+ai@gnieh.org>
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String.getBytes()/getBytes(charset)in_builtin_virtual_hooksencoded UTF-16LE unconditionally, ignoring the requested charset.Java's default charset on Android is UTF-8, and
getBytes("UTF-8")is the common case in the obfuscated string/crypto code this VM is used to analyse. Encoding UTF-16LE returned twice as many bytes, so every downstream digest, cipher, or Base64 over the result was wrong — e.g."hi".getBytes("UTF-8")returned[0x68,0x00,0x69,0x00]instead of[0x68,0x69].Fix: honour the charset argument when present (normalising e.g.
UTF_8→utf-8), default to UTF-8, fall back to UTF-8 on an unknown charset, and keep the existingsurrogatepasshandling. One hook, no API change.Found while using DaliVM to recover strings from a real APK; happy to adjust naming/comments.