Can someone tell me how fast AES encrypt in C or C++? I found the AES code in Python:
https://gist.github.com/jeetsukumaran/1291836
and I measured how fast it encrypts. But I can't run the AES code in C. I don't know C and the codes I found don't work on an online interpreter. Maybe someone has a working, clean code and could compare it?
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Background
Yahoo Finance recently (Nov-2022?) started encrypting their returns from queries such as: curl --silent --output - https://finance.yahoo.com/quote/t.
I found some Python code that will decode this in https://github.com/ranaroussi/yfinance/blob/main/yfinance/data.py#L49
Since Python is an Algol-like language, I was hoping it would be a quick port.
Here is where I hit a snag: https://github.com/ranaroussi/yfinance/blob/main/yfinance/data.py#L82
I was hoping for some relief from an existing perl module, such as Crypt::OpenSSL::FASTPBKDF2.
I know just enough about cryptography to hurt myself.
My question(s):
Is there a straightforward port for the Python function EVPKDF? It seems so close, except for the hashAlgorithm="md5" portion of EVPKDF(password, salt, keySize=32, ivSize=16, iterations=1, hashAlgorithm="md5").
The Crypt::OpenSSL::FASTPBKDF2 module doesn't seem to support md5. I know that md5 was defeated over a decade ago, but it seems to be what Yahoo is dishing out, based on the Python code.
Any thoughts are welcome.
My goal is to get the data, and I am not above using a system("openssl kdf..."); call. Not this time, anyway.
Is there an AES based non-cryptographic hash algorithm?
I think this could be useful, as we have AES-NI instructions, such a hash could be very fast.
I'd like to use this for fingerprinting (so its output should be at least 128-bits) and error detection purposes.
(I've googled for this, but all I found is cryptographic hashes)
MeowHash is a new (still not officially released) AES-NI-based hash function that is extremely fast and appears to be very robust for the functions you mentioned (but not cryptography):
Write-up: https://mollyrocket.com/meowhash
Repo: https://github.com/cmuratori/meow_hash
Disclaimer: New to cryptography.
I have an external process that uses OpenSSL to encrypt data, which right now, uses a salt.
An iPhone app grabs that data from a server, downloads it to the app's documents directory, and needs to decrypt it. The iPhone OS does not include the OpenSSL library. You can build it yourself, but it's difficult and tricky. The "easiest" solution I've found, thanks to Stackoverflow's help, is to use CommonCrypto/CommonCryptor.h which is part of the Security Framework.
But the C function to decrypt data needs an iv to correctly decrypt.
Is there a way to derive the iv from the encrypted data (which, to me, seems like it would negate the extra security)? Or do I need to, first, specify the iv somehow and let the iPhone app know what it is? Or, just don't use a salt?
Edit1: To clarify, I'm using OpenSSL to encrypt text in a data file. A script using OpenSSL encrypts the text, uploads to Dropbox, then the app downloads the file from Dropbox, parses it, and attempts to decrypt the text.
Edit2: Yes, I'm using the OpenSSL command line utility with the -pass option.
The IV should be chosen randomly for each message you encrypt. I assume you are using the OpenSSL command line utility, openssl enc, but it's not clear whether you are using password-based encryption (the -pass and -salt options) or specifying the key explicitly (the -K and -IV options).
For the best security, I recommend that you use the -K option, and randomly generate a new IV for each message. Send the IV along with the ciphertext. For example, you could append the ciphertext to the IV in one file, and then strip the IV from the beginning of the file when you are ready to decrypt.
The IV can be public; you don't have to hide it. The important thing is that you use an unpredictable IV for each message.
The iv can not be derived from the encrypted data, it must be either agreed on outside of the communications between the two sides or made public. Also depending on the encryption mode it may not be required, but CBC is the most common and does require an iv. The iv basically makes it harder to glean any information from the first block.
In your case you just need to figure out the iv, either it is static and just hard-code it or it it is transmitted, possibly in a pre-amble, figure out how to extract it from the data.
The iv may be as simple as 0.
One problem with SSL is trying to capture the packets. That can be done easily with the app Charles (link here), it has a free trial. I use it regularly.
Personally I use to compile OpenSSL for a wide variety of functionality, try this tuto http://www.x2on.de/2010/07/13/tutorial-iphone-app-with-compiled-openssl-1-0-0a-library/ really is simple.
Cheers!.
Forgive me if this might be a dumb question but, I'm in an assembly class that was mostly taught using an emulated CPU that was supposed to teach the concepts of assembly code. We haven't even written an Intel program, so I'm trying to adjust. In our emulated CPU, we were able to generate a symbol table file that gave the bytes equivalent for instructions:
http://imgur.com/tw5S8.png
Would I be able to do such a thing with Intel x86 instructions?
Try IDA. It has an option to show binary values of opcodes.
EDIT: Well.. it's a disassembler. Try opening a binary file, and set the number of opcode bytes to show (in Options/General/) to something that is not zero.
If you are looking for an IDE that shows you in real time the opcodes for the instruction you've used, then I don't think you'll find one, because of lack of "market". Can you explain why you need it? Do you want to know just their length, or want to learn them? There is simple pattern for lengths, so by dissasembling many binaries you'll catch it. If it's the opcodes you want.. well, there are lots of them, almost no rules, and practically no use to do it.
I see.. then you have to generate the list file . Your assembler should have an option for that. (for NASM it's -l listfile). Just put any instruction(s) in your .asm file, and generate listing for it. It should contain the binary encoding for each instruction.
First, get Intel Instruction Set Refference, or, better, this link: http://siyobik.info/index.php?module=x86 . There you'll find that most opcodes have several encodings. In your particular case, the bit 1 of the opcode specifies direction, and since both operands are registers, you can toggle the direction and swap the register codes, and the result will be the same. Usually you have this freedom on most register to register arithmetic operations. To check this, try decompiling with IDA this source file:
db 02h, E0h
db 00h, C4h
There is a demo program shipped with fasm.dll which has an editor and hex-viewer:
Are there any very simple cross-platform C++ libs which can do assymetric encription?
Not necessary efficient, just working. I imagine it could be just 3-4 functions in an .h file which do arbitrary precission math and that's it.
I belive using OpenSSL here is an overkill.
http://cryptopp.com/ looks to be what I need.
One might tear it down to individual files, and it has RSA samples.