ECC stands for Elliptic Curve Cryptography. Elliptic curves are a mathematical structure which allow to define cryptographic operations on them.

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Which host key algorithm is best to use for SSH?

When you first connect to an SSH server that is not contained inside your known_hosts file your SSH client displays the fingerprint of the public key that the server gave. I found from this question ...
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220 views

How do I find a PKI smart card reader/writer for development (Microsoft .NET)

I would like to learn how to develop software leveraging PKI smart cards. Ideally, I would use Microsoft Base Smart Card CSP, but I really just need the ability to store symmetric and asymmetric keys ...
2
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1answer
60 views

ECC for future IoT devices?

Elliptic Curve Cryptography(ECC) is one of the powerful cryptographic methods that requires less computational effort. IoT requires a cryptosystem that secures smart services and applications (5As i....
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What elliptic curves are supported by browsers?

Wireshark'ed Firefox 3 request. Their names are nowhere documented. Elliptic curve: secp256r1 (0x0017) Elliptic curve: secp384r1 (0x0018) Elliptic curve: secp521r1 (0x0019) What are the supported ...
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1answer
511 views

RSA BSAFE Crypto-J JCE provider - “Server Hello” returns unassigned Named Curve

I'm using the RSA BSAFE Crypto-J 6.2 JCE provider in Java as SSL/TLS server (in FIPS 140 Compliant Mode for SunJSSE). when I use any elliptic curve based key exchange mechanism the handshake fails ...
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1answer
42 views

Use elliptic curves certificate only if client support them

Is it possible to send an EC certificate to a client if it supports it or send a regular certificate if it doesn't?
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1answer
350 views

Using ECC for PGP-Master Key in combination with Yubikey

I acquired a Yubikey Neo last month. Now I want to use the Smart-Card functionality for PGP. I followed the official guides on the Yubico Website tested it with 2048 RSA Keys and it worked fine. But ...
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3answers
2k views

Why don't more websites implement Perfect Forward Secrecy?

From what I understand, all it takes to enable PFS on a webserver is adding ephemeral cipher suites (ones that use DHE and ECDHE for the key exchange) to the list of cipher suites used in SSL/TLS ...
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2answers
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Is it bad that my ed25519 key is so short compared to a RSA key?

I recently generated a new SSH key in the ed25519 format. The public key is only 69 bytes long while my old RSA key is 373 bytes. From my perception ed25519 is the more recent and secure format. So ...
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1answer
37 views

GPG/Bitcoin usb gadget device

My idea is to take a raspberry pi zero (or any embedded linux board) and shove GPG inside it to encrypt/decrypt/sign data with RSA/ECC (for bitcoin) via USB. Like a USB thing that holds your (...
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3answers
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Which elliptic curve should I use?

I am currently renewing an SSL certificate, and I was considering switching to elliptic curves. Per Bernstein and Lange, I know that some curves should not be used but I'm having difficulties ...
0
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1answer
66 views

How to make a good choice between Symmetric and Asymmetric [closed]

Here and there and read a lot of articles and blog posts titled "Difference Between Symmetric Cryptography and Asymmetric Cryptography". But inside of them they are answered "What is Symmetric ...
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1answer
51 views

How can I use ECC 163?

I will be working with a Sentinel dongle. In the 3rd tab, it says it supports ECC 163. I will be both encrypting and decrypting with the dongle, as well as on a server. The server uses PHP but I can ...
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1answer
88 views

DNSCrypt-proxy: This certificate looks valid

I have just installed dnscrypt-proxy and dnsmasq with DNSSEC but I get a strange message in the logfile from dnscrypt-proxy. [INFO] + DNS Security Extensions are supported [INFO] - [dnscrypt.eu-dk] ...
0
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1answer
219 views

BLS signature java implementation needed (if possible, along with some example code)

I need to sign a string with the shortest digest possible using regular certificate like X.509. As far as I understand, I will have to transform the string to the sequence of bytes, then sign. After ...
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41 views

Presentation format for curve25519 private key?

I'm having trouble finding a presentation format for curve25519 private key. Does any know how its been defined? Will it follow PKCS #8? Related, the OID for the curve is being finalized at draft-...
2
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3answers
473 views

Named curve value 0xffff in 'Server Hello' message

I'm using the RSA BSAFE Crypto-J 6.2 JCE provider in Java as SSL/TLS server (in FIPS 140 Compliant Mode for SunJSSE). It seems like at least Chrome and Firefox cannot establish a connection if ...
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0answers
44 views

Read back in “human readable” text from openssl ec -pubout

I'm looking to understand how/if the output of the openssl ec -in pub.pem -pubin -pubout -text -noout command can be used to reconstitute the public key. I'm hoping it can be a symmetrical operation? ...
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0answers
40 views

Smartcard authentification: encrypt/decrypt or ECDSA?

I'm implementing a simple door access control with smart keyfobs. At the moment I send a 32 byte message to the keyfob which it signs with ECDSA and I verify the authenticity with the public key. ...
3
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1answer
1k views

Why is secp521r1 no longer supported in Chrome, others?

Found a few issue threads, notably for Chrome (Chromium issue #478225), and the browser does appear to have dropped support for the secp521r1 curve (can test your browser using SSLLabs). There were ...
3
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1answer
153 views

Are the elliptical curves in ECDHE and ECDSA the same?

ECDHE is quite widely used and recommend. And it works with elliptical keys and provides forward secrecy. It's used for the key exchange. ECDSA is not widely used though, but it does also use ...
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66 views

Curve25519xsalsa20poly1305 key derivation

I'm working on batch-encryption of files, for a small project of mine. The files are stored encrypted on a removable drive, and the keys are stored on a trustful server. For enhanced safety, I'd like ...
3
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1answer
171 views

LibTomCrypt weird ECC Keys

I recently started working with the LibTomCrypt Library because it claimed to be a well documented C Library to get started with Elliptic Curve Cryptography. In my first little program I created an ...
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3answers
596 views

Is ECDH for SEC P-384 and P-521 broken in Windows 10 / Windows Server 2016 TP3?

UPDATE: Proof of concept code here, console output shown below and all involved certificates are here. Just noticed that ECDiffieHellmanCng.DeriveKeyMaterial(...) behaves differently on Windows 8.1 ...
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2answers
541 views

More secure curve than Curve25519

As far as I know, Curve25519 offers "only" a security level equal to an 128bit symmetric cipher. I'd like to know if there are new (not NIST) curves, which provide a security-level comparable to a ...
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1answer
853 views

How does signing work with Elliptic Curve Crypto?

So I have read up and have a decent understanding of how the crypto works with Elliptic Curve Cryptography. I also think I have an understanding of how signing works with things like Elliptic Curve ...
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1answer
224 views

How to Build Pre-Master Secret [duplicate]

I'm implementing a TLS-like system, which uses ECDHE-RSA-AE-GCM-SHA, and I've faced two interrogations. At the end of the handshake ( and before the ChangeCipherSpec message), both the client and the ...
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1answer
212 views

How to encrypt with ECDSA?

Suppose there's a transaction in the blockchain in which a given address transfers bitcoins to whoever. I need to encrypt a message so only the owner of that address will read it. I have his public ...
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1answer
157 views

Specificity of ECDHE in a TLS handshake

It's just a short question, but I haven't find a clear answer yet... It's in the frame of a TLS-ECDHE handshake. Where does the specificity of the ECDHE, over the DHE, appears ? At which point do ...
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1answer
93 views

Finding ecc private key from plaintext and public key

I am working on a message authentication scheme using libsodium and ed25519. The messages range in size from 256bytes to 1k plus the 56byte signature. With a potential of 90,000 to 350,000 ...
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2answers
108 views

Is it secure to create a Bitcoin address from a private key generated by Rand() instead of cryptographic elliptic curve

I am writing a C++ application that creates a Bitcoin address. I am having a hard time installing openssl for windows and making it work for visual studio. So, I am asking myself, if I create a ...
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Why is ECC more vulnerable than RSA in a post-quantum world?

Forgive me if this should be in the crypto sub, but sometimes the answers there are very mathematical and I would rather have an answer which is a bit lighter on the math but still strong on the tech ...
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1answer
164 views

Confused about RFC 4492: difference between “ECDH-capable public key” and “ECDSA-capable public key”

As per section 5.3 of RFC 4492, I'm confused with the following table: Key Exchange Algorithm Server Certificate Type ---------------------- ----------------------- ...
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2answers
235 views

ECC and RSA 10K stronger claim

There are a lot of websites where it is claimed something akin to this but no explanation on the basis. "ECC key size of 256 bits is equivalent to a 3072-bit RSA key and 10,000 times stronger than a ...
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1answer
374 views

ECDH BouncyCastle KeyAgreement length

I am attempting to obtain a shared secret using BouncyCastle's ECDH methods in C#, however I am receiving a shared key which is much shorter than the 48 bytes I expect it to be. I have a trusted ...
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3answers
7k views

ECC in (Open)PGP

How is with the support for ECC (Elliptic Curve Cryptography) in (Open)PGP so far? It seems that GnuPG (The GNU Privacy Guard) doesn't have an official implementation - but I did find the gnupg-ecc ...
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2answers
232 views

Using Different Algorithms in Single PKI

Assume the following Public Key Infrastructure: |Root CA (RSA) |-Sub CA (RSA) |-Sub CA (ECC) Is there any rational that explains why this would not be an acceptable implementation? Is the ...
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Generating ECDSA certificate and private key in one step

Similar to how it can be easily done for RSA: openssl req -x509 -nodes -newkey rsa:2048 -rand /dev/urandom -keyout example.key -out example.crt -days 365 I'd like to generate a ECDSA cert/key in ...
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1answer
274 views

What's RSA and ECC's role in TLS 1.2? [duplicate]

I'm trying to figure out what is RSA and ECC used for in TLS 1.2 cipher suites. Let's take TLS_ECDHE_RSA_WITH_CHACHA20_POLY1305_SHA256 for example, communication between server and client would look ...
2
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1answer
393 views

EC private key, RSA certificate. Is this realisable?

I was wondering if is it possible to generate EC private key: openssl ecparam -name sect571r1 -out ecparam.pem openssl ecparam -in ecparam.pem -genkey -noout -out eckey.pem then generate ...
2
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2answers
130 views

HPKP and multiple SSL certificates

Some weeks ago, we enabled the HTTP Public Key Pinning header on our website. As per the specification, we included not only the SHA-256 fingerprint of our current RSA key, but also that of a backup (...
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3answers
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What is ECDHE-RSA?

What is the difference between ECDHE-RSA and DHE-RSA? I know that DHE-RSA is (in one sentence) Diffie Hellman signed using RSA keys. Where DH is used for forward secrecy and RSA guards against MITM, ...
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1answer
250 views

What does the EC Private key version field mean?

I have read the question Converting ECC Private key to PKCS#1 format. And I understood that the value of the version field of the traditional EC private key is 01. We can use the command openssl ...
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2answers
3k views

Converting ECC Private key to PKCS#1 format

Is there any way to convert an ECC private key to RSA PKCS#1 format? I have tried converting it to PKCS#8 first using OpenSSL: openssl pkcs8 -topk8 -nocrypt -in EC_key.pem -out pkcs8_key.pem This ...
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1answer
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Securing ECC Private keys

What would be the equivalent to securing ECC private key similar to how RSA private keys are password protected through the PKCS#12 format? Another question I have is: how do I add ECC keys to a ...
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1answer
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SSH Key: Ed25519 vs RSA

A lot of people recommend using Ed25519 instead of RSA keys for SSH. The introduction page of Ed25519 (http://ed25519.cr.yp.to/) says: [..] breaking it has similar difficulty to breaking [..] RSA ...
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openssl ECDHE-RSA… cipher suite selected while using RSA server cert and ECDSA client cert

The scene: s_server using RSA certificate. s_client using ECC-ECDSA certificate. Client authentication is required (option -Verify set on s_server) Cipher-suite selected after handshake is ECDHE-...
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1answer
60 views

length of a session key in EC?

In elliptic curve cryptography what should be the length of session key? Is there a specific metric to choose one, or are they randomly generated? I was studying one paper about defence against a ...
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1answer
630 views

openSSL selects ECDH-RSA instead of ECDH-ECDSA

I am trying to do a secure connection with openSSL between a client and a server that I wrote. When I try to select the cipher suite to use, I do SSL_CTX_set_cipher_list(ctx, ECDH-ECDSA-AES18-GCM-...
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0answers
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Strength and length of Symmetric vs Asymmetric keys [duplicate]

There are many questions surrounding the differences between symmetric and asymmetric encryption keys. I think I've read them all at this point. But I'm still left wondering: Why does a "secure" ...