I've used OpenSSL BIGNUM to implement some cryptosystems and I am now wondering if it also offers big decimal support. I could not find anything in the documentation but perhaps there is an extension/add-on somewhere preferably in C (not C++)?
Note: I am aware of GMP and NTL, I am not looking for those.
Does OpenSSL offer Big Decimal support?
No.
As far as I know OpenSSL uses BigNumber library to implement operation on large numbers, ant this is recommended way to follow for devs.
More info: http://linux.die.net/man/3/bn_print
Related
I'm currently doing a primality test on huge numbers (up to 10M digits).
Right now, I'm using a c program using the GMP library. I did some parallelization using OpenMP and got a nice speedup (3.5~ with 4 cores). The problem is that I don't have enough CPU cores to make it feasible to run with my whole dataset.
I have an NVidia GPU and, I tried to find an alternative to GMP, but for GPUs. It can be either CUDA or OpenCL.
Is there an arbitrary precision library that I can run on my GPU? I'm also open to using another programming language if there is a simple or more elegant way of doing it.
It seems the Julia Language is already able to do multiprecision arithmetic and use the GPU (see here for a simple example combining these two), but you might have to learn Julia and rewrite your code.
The CUMP library is meant to be a GMP substitute for CUDAs, it attempts to make it easier for porting GMP code to CUDAs by offering an interface similar to GMP, for example you replace mpf_... variables and functions by cumpf_... ones. There is a demo you can make if it fits your CUDA. No documentation or support though, you'll have to go through the code to see if it works.
The CAMPARY library from people in LAAS-CNRS might be a shot as well, but no documentation either. It has been applied in more research than CUMP, so some chance there. An answer here gives some clarification on how to use it.
GRNS uses the residue number system on CUDA-compatible processors, it has no documentation but an interesting paper is available. Also, see this one.
XMP comes directly from NVIDIA labs, but seems incomplete and has no docs also. Some info here and a paper here.
XMP 2.0 seems newer but only support sizes up to 32k bits for now.
GPUMP looks promising, but seems not available for download, perhaps by contacting the authors.
The MPRES-BLAS is a multiprecision library for linear algebra on CUDAs, and does - of course - have code for basic arithmetic. Also, papers here and here.
I haven't tested any of those, so please let us know if any of those work well.
I need an HMAC implementation with SHA384 in C. It is needed for some API I'm writing.
If anyone can provide at least a starting point I would be happy. Thanks!
Use the openssl library.
An example of using openssl to generate an SHA384 hash is here: http://www.askyb.com/cpp/openssl-sha384-hashing-example-in-cpp/
It claims to be in C++ but it's pretty much straight C.
I'm running Debian Linux, and for a Lua script I need to create a SHA256 checksum to authenticate requests to Amazon Web Services. They don't say for sure but it looks as if they may want a base64 encoding of the resulting SHA256 checksum.
I'd be happy if someone had done a Lua binding.
I'd be content if someone could help me figure out how to use the command-line /usr/bin/sha256sum for this purpose.
I'd settle for a pointer to C code and deal with the hassle of the binding and the base64 encoding myself.
I surely don't need to reimplement SHA256 for myself; if someone has an implementation in ANSI standard C that they like, please let me know. Or a better solution!
How about LuaCrypto, a front-end for OpenSSL:
http://luacrypto.luaforge.net/
It looks like mushclient has already written a Lua wrapper for a SHA-256 library.
A work-around might be the free signing service at http://apisigning.com/
I'm looking into a mechanism for serialize data to be passed over a socket or shared-memory in a language-independent mechanism. I'm reluctant to use XML since this data is going to be very structured, and encoding/decoding speed is vital. Having a good C API that's liberally licensed is important, but ideally there should be support for a ton of other languages. I've looked at google's protocol buffers and ASN.1. Am I on the right track? Is there something better? Should I just implement my own packed structure and not look for some standard?
Given your requirements, I would go with Google Protocol Buffers. It sounds like it's ideally suited to your application.
You could consider XDR. It has an RFC. I've used it and never had any performance problems with it. It was used in ONC RPC and has an and comes with a tool called rpcgen. It is also easy to create a generator yourself when you just want to serialize data (which is what I ended up doing for portability reasons, took me half a day).
There is an open source C implementation, but it can already be in a system library, so you wouldn't need the sources.
ASN.1 always seemed a bit baroque to me, but depending on your actual needs might be more appropriate, since there are some limitations to XDR.
Just wanted to throw in ASN.1 into this mix. ASN.1 is a format standard, but there's libraries for most languages, and the C interface via asn1c is much cleaner than the C interface for protocol buffers.
JSON is really my favorite for this kind of stuff. I have no prior experience with binary stuff in it though. Please post your results if you are planning on using JSON!
Thrift is a binary format created by Facebook. Here's a comparison with google protocol buffers.
Check out Hessian
There is also Binary XML but it seems not stabilized yet. The article I link to gives a bunch of links which might be of interest.
Another option is SNAC/TLV which is used by AOL in it's Oscar/AIM protocol.
Also check out Muscle. While it does quite a bit, it serializes to a binary format.
Few Thing's you need to Consider
1. Storage
2. Encoding Style (1 byte 2 byte)
3. TLV standards
ASN.1 Parser is the good for binary represenations the best part is ASN.1 is a well-established technology that is widely used both within ITU-T and outside of it. The notation is supported by a number of software vendors.
I don't ever recall coming across anything for C that's as extensive as C++'s Boost library.
You can have a look at glib. It provides quite a few interesting things like containers, unicode support, threading...
Have a look at its documentation
I've never seen anything. Really, C++ templates are the enabling technology for STL and much of boost, and C doesn't have them. I've seen many C-interface libraries for things like image processing, 3D graphics, networking, etc., but never a real general-purpose library like boost. You can find pieces though - threading libraries, string libraries, etc. - that are similar to sections of boost.
Depending on what exactly you're trying to do there is APR (The Apache Portable Runtime library) which is what the Apache http daemon is built on
http://apr.apache.org/
For GUI, there is wxWidgets (formerly wxWindows)
http://www.wxwidgets.org/
Glib does compensate it partially in form of various unicode, string types. If you add Gobject you could get some object programming even some garbage collection.
ACE (Adaptive Communication Environment) is sometimes mentioned. It's not quite an apples-to-apples comparison. Boost provides more "basic building blocks" whereas ACE provides more of an tightly integrated framework geared towards telco products. I have used both extensively and I find Boost vastly superior. One big advantage of Boost is that many of its features will show up in the STL extensions for the upcoming C++0x standard (see, for example, http://en.wikipedia.org/wiki/Technical_Report_1).
or you can look at ccan http://ccan.ozlabs.org/
but no, there really isn't any complete package, glib comes closest