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Questions tagged [elliptic-curve]

In mathematics, an elliptic curve is a smooth, projective algebraic curve of genus one, on which there is a specified point O.

In mathematics, an elliptic curve is a smooth, projective algebraic curve of genus one, on which there is a specified point O (the point at infinity). An elliptic curve is in fact an abelian variety — that is, it is a (necessarily commutative) group with respect to an algebraically defined multiplication — and O serves as the identity element. Often the curve itself, without O specified, is called an elliptic curve.

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SSLHandshakeException: Handshake failed on Android N/7.0

I'm working on an app for which the (power)users have to set up their own server (i.e. nginx) to run the backend application. The corresponding domain needs to be configured in the app so it can connect. I've been testing primarily on my own phone…
Cornelis
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How do I get an ECDSA public key from just a Bitcoin signature? ... SEC1 4.1.6 key recovery for curves over (mod p)-fields

Update: Partial solution available on Git EDIT: A compiled version of this is available at https://github.com/makerofthings7/Bitcoin-MessageSignerVerifier Please note that the message to be verified must have Bitcoin Signed Message:\n as a…
halfbit
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Using ECC Curve25519 to encrypt/decrypt data in Java

I am trying to use Curve25519 in my Android app to encrypt/decrypt AES encryption key locally. I don't need any key exchange, key agreement or signing. Why I need to use that particular curve? Because I need to be able to provide private key myself…
Alex Amiryan
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ECDSA signing file with key from store C#.Net CNG

I'm trying to sign a file with ECDSA using the CNG API and a certificate from the Microsoft Certificate Store. I've read through a lot of documentation and and near done but I get hung up on importing the private key from the certificate. I've done…
Jim
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How does one access the raw ECDH public key, private key and params inside OpenSSL's EVP_PKEY structure?

I'm using OpenSSL's c library to generate an elliptic curve Diffie-Hellman (ECDH) key pair, following the first code sample here. It glosses over the actual exchange of public keys with this line: peerkey = get_peerkey(pkey); The pkey variable and…
Bob Whiteman
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Elliptic Curve Crypto in iOS

I'm trying to incorporate ECC into an iPhone app that is being used for secure communications but I'm having a hard time finding a proper library / tutorial on how to do this in objective-c. I read this post: How to use ECC in iOS But it was posted…
jrushing
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Is there a standardized fixed-length encoding for EC public keys?

I was wondering if there was (and I hope there is) a standard for public key size for ECDH (Elliptic Curve Diffie-Hellman) and ECDSA (Elliptic Curve Digital Signature Algorithm) for every curve type over prime fields (192, 224, 256, 384 and 521).
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Encrypting/decrypting text strings using OpenSSL ECC

How can I use OpenSSL's ECC support to encrypt or decrypt a text string? I am able to generate ECC private/public keys using OpenSSL APIs, but I don't know how to encrypt plain text using those keys.
Sandeep
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How to load Next Generation certificates from the Microsoft keystore using Java 8?

I'm trying to load certificates directly from the Microsoft store in order to avoid having to export certs from the MS store and then import them into a JKS store. I managed to get certs created from a typical AD CS web server template using legacy…
fstarnaud
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.NET implementation (libraries) of elliptic curve cryptography

Please can you suggest any implementation of elliptical curve cryptography to be used on .NET platform? Also if you have used them, can you tell me the recommended curves that should be used? [EDIT] As @FatCat mentioned, its implementation is…
Hemant
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RDSA implementation on sage

First of all I must say my knowledge with using Sage math is really very limited, but I really want to improve an to be able to solve these problems I am having. I have been asked to implement the following: 1 - Read in FIPS 186-4…
sharp_c-tudent
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Is there a difference between ECDH and ECDSA keys?

I'm building a network application that uses BouncyCastle as a cryptography provider. Let's say you have this to generate a keypair: ECParameterSpec ecSpec = ECNamedCurveTable.getParameterSpec("prime192v1"); KeyPairGenerator g =…
Hut8
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Derive Key with ECDiffieHellmanP256

I am working on a project to integrate with the new Push API that exists in Firefox and is being developed as a W3C standard. Part of this is encrypting the data. The server will receive a Diffie Hellman P256 Curve (Generated in JS using var key =…
Dan Drews
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disable weak ciphers in SSL connection

I am using the function SSL_CTX_set_cipher_list to set the ciphers supported for the SSL connection. What argument to pass to SSL_CTX_set_cipher_list to disable weak ciphers. I tried passing ALL:!ADH:!LOW:!EXP:!MD5:@STRENGTH but it doesn't seem to…
Ravi
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Python -- matplotlib elliptic curves

I'm teaching myself about matplotlib and Python and I'm having a difficult time plotting an equation for an elliptic curve. I have the equation down but I'm not doing the y^2 This is as much trouble as I was able to get myself into so far: from…
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