Aiden Luo created GUACAMOLE-616: ----------------------------------- Summary: Incorrect instruction element length handle because of Java's char type Key: GUACAMOLE-616 URL: https://issues.apache.org/jira/browse/GUACAMOLE-616 Project: Guacamole Issue Type: Bug Components: guacamole-common Affects Versions: 0.9.14 Reporter: Aiden Luo
The definition of guacamole instruction: {quote}The Guacamole protocol consists of instructions. Each instruction is a comma-delimited list followed by a terminating semicolon, where the first element of the list is the instruction opcode, and all following elements are the arguments for that instruction: OPCODE,ARG1,ARG2,ARG3,...; Each element of the list has a positive decimal integer length prefix separated by the value of the element by a period. This length denotes the number of Unicode characters in the value of the element, which is encoded in UTF-8: LENGTH.VALUE {quote} Which means the element's values will be encoded in UTF-8。That means we must use correct UTF-8 encoder/decoder to handle the instruction. But in guacamole-common, the parser use Java's char type to parse which only can store partial Unicode char. Problem code [https://github.com/apache/guacamole-client/blob/master/guacamole-common/src/main/java/org/apache/guacamole/protocol/GuacamoleParser.java#L164] {code:java} if (state == State.PARSING_CONTENT && charsParsed + elementLength + 1 <= length) { // Read element String element = new String(chunk, offset + charsParsed, elementLength); charsParsed += elementLength; elementLength = 0; ...{code} In the code above, bytes of a unicode char may not equal to a java char. I also check the guacamole-server implementation, all work fine. Correct code [https://github.com/apache/guacamole-server/blob/master/src/libguac/parser.c#L113] {code:java} /* Advance to next character */ parser->__element_length--; char_buffer += char_length;{code} -- This message was sent by Atlassian JIRA (v7.6.3#76005)