RSA is a common public key algorithm, which can be used for encryption and signature. It is a core component of most the security protocols used on the Internet, including the SSL/TLS protocol suite.

learn more… | top users | synonyms

2
votes
1answer
30 views

Public Key Pinning and subdomains

Shortly I have intend to install new webserver and I'd like to secure users a little bit more. I already have domain, (virtual) server and everything else that matters when configuring a server. ...
0
votes
0answers
38 views

DSA, ECDSA and RSA

Conventional wisdom these days is that in the context of SSH keys, DSA is insecure and RSA is preferred (or that they are both fine, but RSA is more secure, depending on who you ask). As I understand ...
0
votes
0answers
30 views

breaking down RSA/ECB/OAEPWITHSHA-256ANDMGF1PADDING

So Java has a mode called RSA/ECB/OAEPWITHSHA-256ANDMGF1PADDING. What does that even mean? RFC3447, Public-Key Cryptography Standards (PKCS) #1: RSA Cryptography Specifications Version 2.1, section ...
2
votes
2answers
38 views

Significance of the difference between DSA and RSA in signature verifying speed

I have run openssl speed and the output on my CPU for longest available DSA key size, which is 2048 bits: sign verify sign/s verify/s rsa 2048 bits 0.029185s ...
0
votes
2answers
143 views

Diffie-Hellman and MIM attack, and server identity

Diffie-Hellman and MIM attack: When variants of Diffie-Hellman algorithms like DHE, ECDHE etc. are used in SSL handshake for key exchange then can it become prone to man in middle (MIM) attack. ...
0
votes
0answers
38 views

Why isn't a table used to solve the large number factoring problem? [migrated]

Lots of modern encryption (RSA comes to mind) are based on the fact that factoring large numbers is hard. However, multiplying large numbers is much easier, and table lookups are very easy. Since ...
1
vote
0answers
27 views

How to unwrap exported key from safenet HSM? [closed]

I am trying to write a software that will inject keys generated inside an HSM into a POS device, in the same way as described here I'm using the Safenet emulator(software-mode) + the wrap/unwrap ...
-1
votes
0answers
44 views

How to ensure message integrity for ciphers created via RSA algorithm [migrated]

In order to send a message over an unsecured channel I have to first encrypt the data using the RSA algorithm. The implementation I use is the javax.crypto.Cipher in Java 7. I'm aware of chosen ...
1
vote
1answer
52 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 ...
5
votes
2answers
113 views

Is RSA useless when my app is fully decompiled?

I've programmed an Android game with Unity Engine. As you know in Unity, scripts compiled into one file named "Assembly-CSharp.dll". I wrote my scripts in C#. After I compiled whole game into .apk, I ...
1
vote
0answers
24 views

Sharing master cert and verifying certs with that [migrated]

I'm working on an application which has to download some files frequently. I thought signing files is a good idea. So first thing I thought to do is to create a master cert and somehow distribute it ...
3
votes
1answer
85 views

GnuPG - Problems with large RSA keys

I have read that GnuPG limits the size of RSA keys to 4096-bits because this could lead to problems with running out of secure memory. But in which operation is this the case? Generating the keys? ...
1
vote
1answer
76 views

SSL key decryption [duplicate]

I am wondering if I can get the SSL Key given the following conditions: Encrypted Text is known Decrypted Text is known Any ideas on how I can create a program that does this?
2
votes
2answers
87 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 ...
2
votes
1answer
83 views

Use RSA Encryption With ASP.NET

My goal is to implement asymmetric encryption in an ASP.NET website to secure user-entered Social Security Numbers. I want to encrypt the SSNs with a public key, and only display a masked version, to ...
2
votes
1answer
78 views

Using RSA for Web Application Authentication

I have a network that is only accessible through bastion servers over ssh. In it, I am developing web applications that are exposed to end users via GUI's served up over websockets. All traffic into ...
3
votes
1answer
55 views

How bad an idea is intentionally using short RSA keys for signing CloudFront private-content URLs?

While pondering a question on SO about efficiently generating signed private-content URLs for CloudFront I decided to check what sorts of savings could be found by using a shorter RSA key. With the ...
0
votes
1answer
84 views

I need to transfer user's private key (RSA) to my App. Is file sharing a good solution?

I've asked a similar question here earlier iOS: Is it ok to store a RSA private key (use to decrypt text) in your application document directory? However, the person recommend me to use keychain ...
4
votes
3answers
101 views

When generating a 4096 bit RSA key pair, do both the private and the public key always have exactly 4096 bits?

When generating a 4096 bit RSA key pair, do both the private and the public key always have exactly 4096 bits, thus do not start with a 0 in binary representation?
4
votes
1answer
154 views

Sending Encrypted Messages with Hybrid RSA, AES and HMAC SHA-256

Is this a Secure strategy for sending a large Encrypted Message using Hybrid RSA 2048, AES 256 and authenticated with HMAC SHA-256: Given the Alice already has Bob's RSA Public Key, Alice: ...
3
votes
2answers
58 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 ...
8
votes
4answers
1k views

Is this RSA/AES combination good?

The team of developers I am part of is trying to develop a safe way to exchange sensitive data between a server and mobile devices. We have come up with the following algorithm: Device generates ...
3
votes
2answers
116 views

Why can I sign but not encrypt?

-edit- After following a chain of links from this question I see this is similar/duplicate of Why should one not use the same asymmetric key for encryption as they do for signing? but this question ...
0
votes
0answers
39 views

Is there a pre-established method for cracking RSA SecureID codes?

I am using the most modern version of RSA SecureID's tokens with a RSA server (used with a lot of governments and larger organizations ). I was just wondering if there was a pre-established method for ...
1
vote
1answer
73 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 ...
1
vote
1answer
161 views

How to prepare FATCA data transmission files with open source tools [closed]

Here is the context: to transmit FATCA data to US IRS service the IDES protocol defines the following steps sign the XML Payload.xml file with enveloping signature, SHA-256 with RSA private key, as ...
1
vote
1answer
41 views

Why FATCA IDES “protocol” does not use RSA encrytion directly on Zip archive ?

Here is the context: to transmit FATCA data to US IRS service the IDES protocol defines the following steps sign the XML Payload.xml file with enveloping signature, SHA-256 with RSA private key, as ...
1
vote
1answer
41 views

What's the signature structure in TLS server key exchange message?

I'm writing a TLS server. While handling ECDHE-RSA cipher suite, the server key exchange is needed. According to Elliptic Curve Cryptography (ECC) Cipher Suites for Transport Layer Security (TLS) ...
2
votes
2answers
405 views

Why is there a “des-ede3-cbc” in my rsa private key?

I have created an OpenSSL RSA private key and certificate request with 4096 bit with the following command: openssl req -newkey 4096 When I view the private key with openssl asn1parse -in privkey ...
2
votes
2answers
51 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 ...
2
votes
0answers
55 views

Good Library for RSA-2048 in C with some restrictions [closed]

I'm looking for a C/C++ implementation of RSA with a 2048 bit key (preferably read from a file). My target is an embedded platform, so it comes with some odd restrictions. The hardware restricts us ...
0
votes
0answers
12 views

Risk to pgp secret keys with known cleartext/ciphertext? [duplicate]

There are a couple of schemes which encrypt IMAP message stores to yourself using GPG/PGP. Which makes initial sense and would keep casual snoopers from getting email. But it raises a question as ...
2
votes
2answers
231 views

Chrome status warning on a netbanking secure site connection [duplicate]

I visited my bank's web banking site and clicked on the Green Lock in the address bar of my Google Chrome browser out of curiosity. Under the "Connections" tab Chrome spits out this disturbing ...
4
votes
2answers
170 views

How much faster does a GPU or FPGA crack an RSA key compared to a CPU?

Are there any significant speed up in time on cracking an RSA key (either brute-force or factoring with general number field sieve) using a GPA or FPGA compared to a CPU? If there is a speed ...
0
votes
1answer
39 views

Passing data among 3 parties with public key encryption

There are three parties involved in a repeated data transfer process: Client C, Broker B and Provider P. There might be multiple clients C. Broker B manages P's customer database. Each customer has a ...
0
votes
1answer
186 views

RSA/ECB/PKCS1Padding: Encypting a Session Key Javascript

How to do ECB mode when dealing with RSA? I dont understand it. The Aadhar authentication doc (http://uidai.gov.in/images/FrontPageUpdates/aadhaar_authentication_api_1_6.pdf Page 33) says that we have ...
0
votes
2answers
63 views

FREAK attack - why doesn't Finished message prevent it?

Here is my understanding of FREAK (let me know if I'm right please): 1) Client wants to use modern RSA in ClientHello 2) MITM forwards Export_RSA 3) Server says ok and sends an export RSA key, ...
2
votes
1answer
113 views

PKCS#1-1.5 encoding - is there a reason to use 00 in block type?

For encryption block looking like this: EB = 00 || BT || PS || 00 || Data where BT - block type and PS - padding string, I've read that we use three types of BT - 00, 01, 02. Now, since 00 and 01 are ...
1
vote
2answers
120 views

Encryption / Decryption algorithm generic across JRE (Sun/IBM)

Is there any encryption algorithm that is generic across all platforms? Is RSA generic across SUN/IBM JRE? Another question: will base64Encoder / base64Decoder sun.misc.BASE64Decode / ...
0
votes
1answer
66 views

How ECDHE is signed by RSA in ECDHE_RSA cipher

About ciphers that use ECDHE as Key Exchange and RSA as Authentication: How exactly this two algorithms work together, is ECDHE process encrypted by RSA public key? What are the DH parameters? ...
3
votes
2answers
314 views

RSA public key and private key lengths

I'm having a problem understanding the size of an RSA public key and its private key pair. I saw different key sizes for RSA algorithm (512, 1024,... for example), but is this the length of public ...
4
votes
2answers
81 views

Secret, Public, and Private Keys?

...and nonces. Can someone show an example of how this actually works using small intelligible numbers? For example: secret key: "100" public key: "10" private key: "1000" I am just trying to ...
6
votes
4answers
944 views

What is the role of RSA in ECDHE-RSA? [duplicate]

I have read some textbooks and not found a convincing explanation. In the cipher suite ECDHE-RSA-AES128-GCM-SHA256, what is the role of RSA in the first part (ECDHE-RSA)? This part of the cipher ...
4
votes
1answer
640 views

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 ...
4
votes
1answer
124 views

Why did browsers deprecate 1024-bit RSA, but retain SHA-1?

I was reading Mozilla's security blog Phasing out Certificates with 1024-bit RSA Keys. Effectively, some browsers are deprecating 1024-bit RSA for CAs and Subordinate CAs because the certificate must ...
1
vote
1answer
68 views

Who uses 1024-bit RSA?

I know they're deprecated, but does anyone still use 1024 bit RSA encryption or certificates? Do you know of any examples of systems that use it today? What would be the implication if someone ...
3
votes
1answer
106 views

Managing keys generated with insufficient entropy

Since the Linux RNG which provides /dev/random (and by extension /dev/urandom) is seeded by "mouse and keyboard activity, disk I/O operations, and specific interrupts" (source, PDF) and since virtual ...
2
votes
1answer
76 views

Choose your own exponents in RSA?

In another interesting post, one of the developers/security researchers behind Phuctor suggests that using different exponents with RSA keys will "[increase] the costs of attacking your setup ...
2
votes
2answers
77 views

Offline RSA strong prime test similar to Phuctor?

One of the ways that RSA keys get consistently owned is when they're generated without enough entropy. Dan Kaminsky refers to a study which found that 1 in 200 RSA keys were badly generated and these ...
1
vote
1answer
58 views

Prevent padding oracle attack on key exchange process

I found in my searches that the padding oracle attack can be used against the RSA with PKCS1PAdding or OAEP padding, and I used this algorithm for a symmetric key exchange. How can I prevent a padding ...