hackathon | Bitcoin Hackathon in India by Coinsecure | Cryptography library

 by   coinsecure Java Version: Current License: No License

kandi X-RAY | hackathon Summary

kandi X-RAY | hackathon Summary

hackathon is a Java library typically used in Security, Cryptography, Bitcoin applications. hackathon has no bugs, it has no vulnerabilities and it has low support. However hackathon build file is not available. You can download it from GitHub.

Coinsecure has been working constantly to refine and create an ecosystem around Bitcoin in India. With this in mind, we are now working towards an initiative to get more Developers across India learning and building on Bitcoin. We are looking for the 3 best applications that can be built for trading leverage using the Coinsecure's api. We are looking at this as an opportunity to further test and refine our API, generate more interest around Bitcoin development and integration.

            kandi-support Support

              hackathon has a low active ecosystem.
              It has 3 star(s) with 3 fork(s). There are 4 watchers for this library.
              It had no major release in the last 6 months.
              There are 0 open issues and 2 have been closed. On average issues are closed in 0 days. There are no pull requests.
              It has a neutral sentiment in the developer community.
              The latest version of hackathon is current.

            kandi-Quality Quality

              hackathon has no bugs reported.

            kandi-Security Security

              hackathon has no vulnerabilities reported, and its dependent libraries have no vulnerabilities reported.

            kandi-License License

              hackathon does not have a standard license declared.
              Check the repository for any license declaration and review the terms closely.
              Without a license, all rights are reserved, and you cannot use the library in your applications.

            kandi-Reuse Reuse

              hackathon releases are not available. You will need to build from source code and install.
              hackathon has no build file. You will be need to create the build yourself to build the component from source.

            Top functions reviewed by kandi - BETA

            kandi has reviewed hackathon and discovered the below as its top functions. This is intended to give you an instant insight into hackathon implemented functionality, and help decide if they suit your requirements.
            • Monitor for a certain order
            • Checks the precondition to see if it is not supported .
            • Writes the Exif data to the Exif entry .
            • Reads a response .
            • Prompt the user to enter a JavaScript prompt
            • Find the most specific attribute value .
            • Process the response headers .
            • Called when a beacon service is connected .
            • Completes the given edit .
            • Choose a response source based on the current request .
            Get all kandi verified functions for this library.

            hackathon Key Features

            No Key Features are available at this moment for hackathon.

            hackathon Examples and Code Snippets

            No Code Snippets are available at this moment for hackathon.

            Community Discussions


            ECSDA sign with Python, verify with JS
            Asked 2022-Apr-10 at 18:16

            I'm trying to achieve the exact opposite of this here where I need to sign a payload in Python using ECDSA and be able to verify the signature in JS.

            Here is my attempt, but I'm pretty sure I'm missing something with data transformation on either or both ends.

            (Key types are the same as in the answer provided to the question above)

            I've tried some other variations but nothing worked so far.

            (The verification on JS returns False)




            Answered 2022-Apr-10 at 18:16

            The main problem is that both codes use different signature formats:
            sign_payload() in the Python code generates an ECDSA signature in ASN.1/DER format. The WebCrypto API on the other hand can only handle the IEEE P1363 format.
            Since the Python Cryptography library is much more convenient than the low level WebCrypto API it makes sense to do the conversion in Python code.

            The following Python code is based on your code, but additionally performs the transformation into the IEEE P1363 format at the end:

            Source https://stackoverflow.com/questions/71818496


            How to calculate sha 512 hash properly in .NET 6
            Asked 2022-Mar-30 at 04:56

            In .NET 6 code from How can I SHA512 a string in C#?



            Answered 2021-Nov-27 at 16:16

            In my case I was using RNGCryptoServiceProvider in .NET 5 but when I updated to .NET 6 I got the same warning. After reading about it in this issue I changed my code from this:

            Source https://stackoverflow.com/questions/70109573


            Crypto-js encryption and Python decryption using HKDF key
            Asked 2022-Mar-28 at 11:29

            Based on the example provided here on how to establish a shared secret and derived key between JS (Crypto-JS) and Python, I can end up with the same shared secret and derived key on both ends.

            However, when I try to encrypt as below, I cannot find a way to properly decrypt from Python. My understanding is that probably I am messing with the padding or salts and hashes.



            Answered 2022-Mar-28 at 11:29

            The issue is that the key is not passed correctly in the CryptoJS code.

            The posted Python code generates LefjQ2pEXmiy/nNZvEJ43i8hJuaAnzbA1Cbn1hOuAgA= as Base64-encoded key. This must be imported in the CryptoJS code using the Base64 encoder:

            Source https://stackoverflow.com/questions/71632056


            Exception "System.Security.Cryptography.CryptographicException" after Publishing project
            Asked 2022-Mar-19 at 05:01

            Everytime I publish my Blazor Server-project to my website domain, and opening the website, this exception occurs, and there's little to no help Googling it:

            And it says AppState.cs: line 21, so here's the codeline for it:

            This exception is not happening under debugging localhost. When I delete localStorage from the browser on my website, and refreshing, then everything works. But I don't want my customers having this exception and having to tell them to delete the localstorage everytime I'm publishing.

            My Program.cs if necessary:



            Answered 2022-Mar-16 at 13:16

            Try to set Load User Profile to true in your IIS app pool in the advanced settings. see this answer, I hope that will help you!

            Source https://stackoverflow.com/questions/71494715


            Chaum blind signature with blinding in JavaScript and verifying in Java
            Asked 2022-Mar-04 at 16:01

            I'm experimenting with Chaum's blind signature, and what I'm trying to do is have the blinding and un-blinding done in JavaScript, and signing and verifying in Java (with bouncy castle). For the Java side, my source is this, and for JavaScript, I found blind-signatures. I've created two small codes to play with, for the Java side:



            Answered 2021-Dec-13 at 14:56

            The blind-signature library used in the NodeJS code for blind signing implements the process described here:

            No padding takes place in this process.

            In the Java code, the implementation of signing the blind message in signConcealedMessage() is functionally identical to BlindSignature.sign().
            In contrast, the verification in the Java code is incompatible with the above process because the Java code uses PSS as padding during verification.
            A compatible Java code would be for instance:

            Source https://stackoverflow.com/questions/70324926


            KJUR jws jsrsasign: Cannot validate ES256 token on JWT.io
            Asked 2022-Mar-03 at 06:41

            We are trying to make a JWT token for Apple Search Ads using the KJUR jws library. We are using the API documents from Apple:


            We are generating a private key (prime256v1 curve):

            openssl ecparam -genkey -name prime256v1 -noout -out private-key.pem

            Next we are generating a public key from the private key:

            openssl ec -in private-key.pem -pubout -out public-key.pem

            Next we setup the header and payload:



            Answered 2022-Mar-02 at 07:47

            The issue is caused by an incorrect import of the key.

            The posted key is a PEM encoded private key in SEC1 format. In getKey() the key is passed in JWK format, specifying the raw private key d. The PEM encoded SEC1 key is used as the value for d. This is incorrect because the raw private key is not identical to the SEC1 key, but is merely contained within it.

            To fix the problem, the key must be imported correctly. jsrsasign also supports the import of a PEM encoded key in SEC1 format, but then it also needs the EC parameters, s. e.g. here. For prime256v1 aka secp256r1 this is:

            Source https://stackoverflow.com/questions/71307444


            Is it possible to get ISO9796-2 signature with Trailer = 'BC' in Javacard?
            Asked 2022-Feb-24 at 10:46

            I trying to get the RSA signature as described in Annex A2.1 of EMV book 2. As I understand it was described in ISO9796-2 as scheme 1, option 1. So, the resulting signature should contain a Header equal to '6A' and a Trailer equal to 'BC'.

            The algorithms ALG_RSA_SHA_ISO9796 and ALG_RSA_SHA_ISO9796_MR are the only suitable that I could find. But they acting like scheme 1, option 2 with a Trailer equal to '33cc'

            Is it possible to get a signature with Trailer = 'BC'?

            Javacard example code:



            Answered 2022-Feb-24 at 10:46

            You can generate such signature using Cipher.ALG_RSA_NOPAD in decrypt mode.


            Source https://stackoverflow.com/questions/71243483


            How to transfer custom SPL token by '@solana/web3.js' and '@solana/sol-wallet-adapter'
            Asked 2022-Jan-29 at 21:02

            Hello I am trying to transfer a custom SPL token with the solana-wallet adapter. However i am having trouble getting the wallet's secret key/signing the transaction.

            I've looked at these answers for writing the transfer code but i need to get the Singer and i have trouble figuring out how with solana-wallet adapter. These examples hardcode the secret key and since i'm using a wallet extension this is not possible.

            How can you transfer SOL using the web3.js sdk for Solana?

            How to transfer custom token by '@solana/web3.js'

            according to this issue on the webadapter repo https://github.com/solana-labs/wallet-adapter/issues/120 you need to:

            1. Create a @solana/web3.js Transaction object and add instructions to it
            2. Sign the transaction with the wallet
            3. Send the transaction over a Connection

            But i am having difficulty finding examples or documentation as to how to do step 1 and 2.



            Answered 2021-Dec-06 at 13:51

            So i found a way to do this, it requires some cleanup and error handling but allows for a custom token transaction via @solana/wallet-adapter.

            Source https://stackoverflow.com/questions/70224185


            From base64-encoded public key in DER format to COSE key, in Python
            Asked 2022-Jan-01 at 10:34

            I have a base64-encoded public key in DER format. In Python, how can I convert it into a COSE key?

            Here is my failed attempt:



            Answered 2022-Jan-01 at 07:49

            The posted key is an EC key for curve P-256 in X.509 format.

            With an ASN.1 parser (e.g. https://lapo.it/asn1js/) the x and y coordinates can be determined:

            Source https://stackoverflow.com/questions/70542577


            Why are signatures created with ecdsa Python library not valid with coincurve?
            Asked 2021-Dec-25 at 14:41

            I'm switching from the pure Python ecdsa library to the much faster coincurve library for signing data. I would also like to switch to coincurve for verifying the signatures (including the old signatures created by the ecdsa library).

            It appears that signatures created with ecdsa are not (always?) valid in coincurve. Could someone please explain why this is not working? Also, it seems that cryptography library is able to validate both ecdsa signatures and coincurve signatures without issues, consistently.

            What is even more confusing, if you run below script a few times, is that sometimes it prints point 3 and other times it does not. Why would coincurve only occasionally find the signature valid?



            Answered 2021-Dec-25 at 14:41

            Bitcoin and the coincurve library use canonical signatures while this is not true for the ecdsa library.

            What does canonical signature mean?
            In general, if (r,s) is a valid signature, then (r,s') := (r,-s mod n) is also a valid signature (n is the order of the base point).
            A canonical signature uses the value s' = -s mod n = n - s instead of s, i.e. the signature (r, n-s), if s > n/2, s. e.g. here.

            All signatures from the ecdsa library that were not been successfully validated by the coincurve library in your test program have an s > n/2 and thus are not canonical, whereas those that were successfully validated are canonical.

            So the fix is simply to canonize the signature of the ecdsa library, e.g.:

            Source https://stackoverflow.com/questions/70477905

            Community Discussions, Code Snippets contain sources that include Stack Exchange Network


            No vulnerabilities reported

            Install hackathon

            You can download it from GitHub.
            You can use hackathon like any standard Java library. Please include the the jar files in your classpath. You can also use any IDE and you can run and debug the hackathon component as you would do with any other Java program. Best practice is to use a build tool that supports dependency management such as Maven or Gradle. For Maven installation, please refer maven.apache.org. For Gradle installation, please refer gradle.org .


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