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What on earth is PAM anyway? Are there any tools for changing passwords etc. that are in PAM-MySQL? I need to retrieve misc. UNIX user information such as one's home directory coming from MySQL. Can pam-mysql do this? How can I quickly tell in which way a given password is encrypted, PASSWORD(), CRYPT()-ed, or md5()? I set up saslauthd (of Cyrus-SASL) to use PAM-MySQL for authentication and noticed some authentication mechanisms such as CRAM-MD5 don't work. Why? PAM-MySQL is licensed under GNU Public License and I heard that GPL requires the program that links to a GPL'ed shared binary object at runtime also being covered by GPL. Is it safe to use PAM-MYSQL from a program with a license that is incompatible with GPL? I was able to build PAM-MySQL without problems, but MD5 doesn't work. Why? I could not build pam-mysql on Solaris with the official MySQL binary package. How can I fix this?

The Mono C# compiler is considered feature complete for C# 1.0 and almost complete for 2.0 (ECMA). The 1.0 compiler has received more testing and is considered more mature than our 2.0 compiler, bug reports can be filed on our bug tracking system. Mono's C# compiler is called MCS and it is able to compile itself and many more C# programs (there is a test suite included that you can use). It is routinely used to compile Mono, roughly four million lines of C# code and a few other projects. The compiler is also fairly fast. On a IBM ThinkPad t40 it compiles 18,000 lines of C# code per second.

GNU m4 is an implementation of the traditional Unix macro processor. It is mostly SVR4 compatible although it has some extensions (for example, handling more than 9 positional parameters to macros). GNU m4 also has built-in functions for including files, running shell commands, doing arithmetic, etc. GNU m4 is a macro processor in the sense that it copies its input to the output expanding macros as it goes. Macros are either builtin or user-defined and can take any number of arguments. Besides just doing macro expansion m4 has builtin functions for including named files, running UNIX commands, doing integer arithmetic, manipulating text in various ways, recursion etc... m4 can be used either as a front-end to a compiler or as a macro processor in its own right. The latest stable version is 1.4.4 GNU m4 is being actively developed, and version 2.0 will have many new features, such as better input control, multiple precision arithmetic and loadable modules. Information about the future of GNU m4 is at http://savannah.gnu.org/projects/m4/. GNU m4 is maintained by Gary V. Vaughan. Report bugs to [email protected]. Online Manual is available at http://www.gnu.org/software/m4/manual/index.html

Abstract—JPEG 2000 is an international standard for still image compression in the 21st century. Part 8 of the standard, named JPSEC, is concerned with all the security aspects, in particular to access control and authentication. This paper presents a novel access control scheme for JPEG 2000 image code-streams. The proposed scheme is secure against collusion attacks and highly efficient. The scheme is also very flexible, allowing access control to JPEG 2000 image code-streams according to any combination of resolution, quality layer and region of interest. The “encrypt once, decrypt many ways” property of our scheme is designed to work seamlessly with the “compress once, decompress many ways” feature of the JPEG 2000 image code-streams. Our prototype implementation shows that the scheme is practical and is completely compatible with the core part of the JPEG 2000 standard.

Abstract An important aspect of JPEG2000 is its “compress once, decompress many ways” property [1], i.e., it allows users with different preferences, privileges or capabilities to extract various sub-images all from a single compressed image code-stream. In this paper, we present a flexible and scalable scheme to authenticate JPEG2000 images disseminated by a untrusted third-party server over open networks. The proposed scheme is fully compatible with JPEG2000 and possesses a “sign once, verify many ways” property, i.e., it allows users to verify the authenticity and integrity of different sub-images extracted from a single compressed code-stream protected with a single digital signature. Furthermore, the use of aggregated digital signatures reduces both computation and communication overhead on the user side for batch image authentication.

Abstract—This paper presents three scalable and efficient schemes for authenticating MPEG-4 streams: the Flat Authentication Scheme, the Progressive Authentication Scheme, and the Hierarchical Authentication Scheme. All the schemes allow authentication of MPEG-4 streams over lossy networks by integrating seamlessly digital signatures and erasure correction coding with MPEG-4’s fine granular scalability. A prominent feature of our schemes is their “sign once, verify many ways” property, i.e., they generate only one digital signature per compressed MPEG-4 object group, but allow clients to verify the authenticity of any down-scaled version of the original signed object group.