Cryptography is the practice and study of logical means used to achieve information confidentiality, integrity and authenticity. It covers, among other things, encryption (making some data unreadable except for those who know a given secret element, called a key), data hashing (in particular for ...

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141 views

Windows Certificate Services: Is it possible to enroll a SmartCard certificate AND have key archival?

I'm using ACOS5-64 Client Kit, I want to enroll for a certificate with key archival. I tried to do so by duplicating the SmartCard template and checked Archive subject's encryption private key option ...
4
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0answers
97 views

Which block cipher should be used in TLS 1.2 (while keeping 1.3 in mind)?

I have been looking a bit at the various block ciphers for TLS. As everyone should (pipe dream) have migrated to TLS 1.2 by now it should be considered how to prepare for TLS 1.3, when it has been ...
3
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0answers
41 views

security of libgcrypt when cross-compiling for windows?

Looking at libgcrypt, specifically secmem.c it seems that it does not account for windows-specific memory handling (e.g. VirtualLock) and in fact there is a very troubling comment: #elif defined (...
3
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81 views

Is there a benefit in measuring randomness? How would it be done?

Is there any benefit in determining how random a given file, stream, signal is? I guess this would be useful to determine If something is (poorly) encrypted To verify the proper encryption of a ...
3
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0answers
60 views

Reference Implementation for Shoup's ECIES?

ECIES is part of both ISO/IEC and IEEE. There's a interop bug between Crypto++'s ECIES and Bouncy Castle's ECIES. I know where the bug lies, and I've been trying to determine who is "right" (for some ...
3
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0answers
161 views

Main difference between Yahalom and Needham-Schroeder key exchange protocols

I am just wondering what is the main difference between the Yahalom and Needham-Schroeder key exchange protocols? Which protocol uses less computational power?
2
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138 views

How to enable ECDHE in openjdk-1.8.0 in CentOS 6.7?

I have seen many posts that hinted ECDHE is available in the SunEC provider way back in openjdk-1.6.0. My environment: CentOS 6.7 with openjdk 1.8.0.71-1.b15.el6_7. No ECDHE. Made 2 changes in jre/...
2
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0answers
47 views

How rf remotes for “cloning” rolling code find matching codes?

I've been tinkering with a rf (garage door) remote control that has a scanner mode (google JMA SR-48 for details). This mode works for Mutancode and Erreka which I assume would be similar to KeeLoq. ...
2
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0answers
18 views

Is the crypto-key pair in IPv6 SeND persistent?

IPv6 introduces the NDP extension SeND to help mitigate identity theft, however, is the non-PKI public/private key pair used during the process persistent to some degree, or generated on every ...
2
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0answers
40 views

Let users sign in with eIDs - do I need government authorisation? (scope: all nation-states)

I've decided to launch a crypto-basic income system. Crypto UBIs are pretty popular now. For me, it seems like an open nation-state ID should exist by now (2015). However, Mike Hearn, Bitcoin core-...
2
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0answers
229 views

Which keys does a bank typically exchange with a card scheme?

I'm trying to understand the different EMV-related keys that are shared between a bank who issues EMV cards and a card scheme, such as Visa or MasterCard. I understand the bank would typically ...
2
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0answers
64 views

What flexibility does a “Third party gamma” offer to U-Prove deployment?

The U-Prove SDK has the following comment: (link) // 1: CA-RA split (a party trusted by the issuer provides the gamma value) Given that the Gamma value (if provided) overrides the Attributes value, ...
2
votes
0answers
112 views

In U-Prove, what is the purpose of “Pseudonyms”, “Committed”, and “Scope” values and how are they used?

U-Prove allows for anonymous authentication and authorization without the involvement of an IdP. When a client generates a presentation proof 3 values can be optionally included, but I can't find ...
1
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0answers
21 views

Recommended Crypto Security Setup (Implemented Algorithms)?

Firstly I'm not a crypto expert, however I know how to use algorithms that other people have defined before in practical usages, that is, as long as they live up to their promises. The thing is that ...
1
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0answers
19 views

Substitution Table in TKIP

In TKIP Encapsulation, we divided the per packet key mixing process into two phases. In phase 1, we are taking three inputs i.e temporal key (128-bit session key), transmitter MAC address (48 bits) ...
1
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0answers
45 views

What is the largest cycle of RSA encryption?

Is there a maximum length of a message before it is impractical to use RSA?
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0answers
52 views

Which is the correct algorithm while checksumming a portion of code?

As part of my research, I came across a technique in a paper which applies checksumming on a portion of code. I want to implement it. Here is the research paper which talks about the checksumming ...
1
vote
0answers
39 views

Create a signed file from the detached signature and the clear text file content

Assuming I have the following: data.txt data.ps7 (the detached signature) Can I generate the bundled signed file ? Any example would be great, using C#, Java or openssl or any other tool ?
1
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51 views

How to acquire the RSACryptoServiceProvider from the existing key container?

The Key containers of "Microsoft Base Smart Card Crypto Provider" are enumerated by setting PP_ENUMCONTAINERS flag for the function CryptGetProvParam(). The enumerated key containers are set to the ...
1
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0answers
62 views

Token-based authentication for specific requirement

We have the following requirement for creating a token in .NET to be used in providing a challenge token and an actual authentication (auth) token. The auth token will then be used to authenticated ...
1
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0answers
117 views

How do ad networks and analytics providers encrypt/hash their traffic?

I am trying to observe what types of information android apps are sending to ad networks that are integrated into apps. I used Fiddler to decrypt the https traffic. However, some ad networks seem to ...
1
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0answers
48 views

Key stretching approaches

I've seen that a number of key stretching algorithms and they involved increasing the number of operations needed to compute the key(i.e. the number of rounds within a hash function). But, I wonder if ...
1
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0answers
331 views

Storing Social Security Numbers in a Database

I'm developing an online application that needs the user's social security number. The application won't be processed on the web server so I'll be using an asymmetric key. So a compromised web server ...
1
vote
0answers
117 views

OpenPGP smartcards compromised by blackhat 2015 simcard hack?

This blackhat was a new sidechannel attack in the SIM-card AES encryption announced. I am currently using the OpenPGP smart/SIM-card version 2.1 to store my PGP-private keys, which is the same model ...
1
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0answers
86 views

How would an improved “read receipt” work as an email, Facebook post, or webpage?

I'm exploring various ways to implement cryptographic read receipts, that would be used to tell the content producer that the content was viewed. In addition to feedback reporting, a response might ...
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49 views

Blinding to mask private key operations

Blinding is often used to mask private key operations when the underlying problem is integer factorization. For example, its used in both RSA and Rabin-Williams signature schemes. This presumes ...
1
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0answers
44 views

Checklist for Data Communication Review in ERP Solution

I am looking out for a checklist for data communication review within ERP application. I understand some of the checks would be related to digital signature, TLS/SSL use, Key Life Cycle management ...
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108 views

Questions about SRP algorithm

I trying to use SRP algorithm but I have some questions: Is that a good choice to use for registration and authorization SRP algorithm with SSL/TLS? And for all other transmission using just SSL/TLS?...
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0answers
184 views

Problem in understanding Blakley's Secret Sharing Scheme

I need to implement Blakley's Secret Sharing Scheme. I have read below mentioned two research papers but still unable to understand how to implement it. 1. Safeguarding cryptographic keys 2. Two ...
1
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0answers
35 views

Key management for hosting applications

We're looking to host a number of client applications in our environment. Some of those will use crypto, e.g. for ssl or database encryption and obviously we'll need to manage keys for that. I am ...
1
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0answers
287 views

RSA 4096 key size difference - “sig” and “sig 3”

Whenever I generate a new 4096 RSA key in my GPG program and export the public key to a text file, I get a text file containing a total of around 52 lines (it varies, one of them is 53 lines). ...
1
vote
0answers
43 views

DTLS CertificateVerify doubt

In DTLS 1.2 RFC 6347, section 4.2.6: CertificateVerify and Finished messages have the same format as in TLS. Hash calculations include entire handshake messages, including DTLS-specific fields: ...
1
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304 views

Storing private messages in a database

I am creating a portal where users can send private messages (PMs) for a very large audience. So I want to encrypt the messages and store them in the database. But I do not want to ask the users for ...
1
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0answers
260 views

Gladman's file encryption library = AES in counter mode with HMAC-SHA1 authentication?

I would like to use Gladman's algorithm to create AES encrypted data in JavaScript. I use the Crypto-JS library, but its performance is horrible. PBKDF2 is terribly slow, so I switched to another ...
1
vote
0answers
61 views

Is it possible to produce incorrect Metadata?

There is an app on xposed installer called XPrivacy for android that let's you decide what information you want your device to give a specific app and for information you don't want to give it ...
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158 views

Putty Event Log

Can anyone explain me the Step by step process of Key Exchange that takes place while accessing Linux machine using Putty ? I found the Event Log of Putty but the Various Key Exchange didn't make very ...
1
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0answers
61 views

Any Suggestion Exchanging shared key between process via port in untrusted machine (infected my malware)?

I am trying to get shared key between Firefox extension and a java program running in same machine. I am communicating both application via socket. My assumption is that malware is running in ...
0
votes
0answers
26 views

ISO 9564 Approved Encryption Algorithms for PIN, why symmetric block ciphers?

I am currently researching best practices in designing a potential PIN management solution for a financial services application and began looking into ISO 9564 as a source of requirements. One of the ...
0
votes
0answers
43 views

Choosing Key and IV in AES-256

I am working on a real-life project for a firm. I have to encrypt data using AES 256 as per specification. I want to know how are the key and IV are really chosen in real world projects. /dev/urandom ...
0
votes
0answers
15 views

What is purpose of fipscheck utility and fipscheck library on Linux?

So I am messing around with dracut and I am trying to get my Linux system in FIPS 140 mode by passing fips=1 to my linux kernel at the boot time from grub. However, I got confused on why dracut ...
0
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0answers
26 views

How crypto module integrity checks mandated by FIPS 140 standard help to make Linux based appliances safer?

After browsing dracut and hmaccalc rpm package source code I found out sha512hmac utility that is used to do do integrity checks for linux kernel (and other binaries) from initramfs boot stage uses ...
0
votes
0answers
29 views

Decrypting keys wrapped by the Storage Root Key (SRK) of a TPM

Lets say I have a symmetric key wrapped with a storage root key (SRK) in a TPM. The SRK cannot be read by an attacker and so I perform the decryption and using the SRK and get the symmetric key in ...
0
votes
0answers
27 views

Secure transfer with proxy person in the middle

I am new to cryptography, so I would like some validation. I have an unusual use case that I haven't found described anywhere and would like to get some help validating my approach. Alice needs ...
0
votes
0answers
21 views

Are there any known weaknesses in SignedXml by Microsoft for SAML?

SingedXml is a common way to verify the signature for SAML in .Net applications. I am wondering if it secure enough, i.e. there is no way to trick it (by making it verify not top-level Assertion or ...
0
votes
0answers
49 views

Digitally signing a digital signature

When might it make sense to digitally sign a digital signature?
0
votes
0answers
49 views

DSS digital signing approach

Under the DSS approach to digital signing, what is the advantage of using two pairs of keys for each signature?
0
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69 views

How to convert the PRIVATEKEYBLOB structure generated using CryptExportKey to bigendian?

Private-key BLOBs, type PRIVATEKEYBLOB, are used to store private keys outside a CSP. Extended provider private-key BLOBs have the following format. PUBLICKEYSTRUC publickeystruc; RSAPUBKEY ...
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102 views

Triple-DES DUKPT CBC PIN variant vs Data variant

Does any know the difference between triple des dukpt decryption algorithm with PIN variant and Data variant? I have done Triple DES DUKPT PIN variant, which generate session key from KSN and BDK. ...
0
votes
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119 views

Would it take long to brute force a md5 hash like this?

1be8917510-36.51929856278002 10bce1af27-99.18403192423284 103fa11cc6-87.21158325206488 Few examples above and as you can see the pattern is: 1xxxxxxxxx-{a percentage (0-100) to 14 decimal places} ...
0
votes
0answers
184 views

Cryptographic Testing

Given an algorithm (say, AES), how to create/generate test vectors? I have tried using the NIST test vectors for AES and found it to be working fine with a package of "chilkat". Suppose, for a ...