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location Netherlands
age 40
visits member for 2 years, 10 months
seen Feb 11 at 11:37

Java and security expert with over 10 years of experience with the language and with the practical application of cryptographic protocols - including the design of protocols within international standardization bodies. Creator of a heavily used common criteria certified product. Over 30 years of experience with computers. Likes kids, cats, reading, movies and several sports.


Oct
30
comment Is there a way to access PKCS5 or 7 padding in OpenSSL without encrypting something?
This question appears to be off-topic because it is about programming (stackoverflow)
Oct
30
comment Is there a way to access PKCS5 or 7 padding in OpenSSL without encrypting something?
Have you seen what PKCS#5/7 padding consists of? The specification of the padding protocol takes a single line in the PKCS#5 and PKCS#7 standards. In this case it is probably easier to program it yourself. By the way, this question really belongs on stackoverflow.
Oct
15
comment How does Eve monitor and obtain ciphertexts?
WiFi generally allows for active attacks. So just performing encryption may not be enough to provide confidentiality of messages (e.g. padding oracle attacks).
Oct
15
comment How does Eve monitor and obtain ciphertexts?
Sorry, downvoted as I found this answer very hard to read and understand. Misspelling cryptography also does not do you any good :P
Oct
15
comment How does Eve monitor and obtain ciphertexts?
For communication protocols it is most of the time better to think of Eve (or Malory) to be able to perform man in the middle attack. Most of the time if you can access the data in transport, you can also change the data in transport. This is especially true if you can setup a WiFi hotspot for instance. And in that case you also need integrity and authenticity (e.g. to avoid padding oracle attacks that may lead to exposure of the plaintext).
Sep
2
comment Symmetric encryption involving load balancers - can't randomize key?
No, you are looking at this the wrong way. The problem you are having is protecting the secret, full stop. Key management is always hardest. Salt has nothing to do with it. Salt is used to protect passwords. There is no reason in your scheme to use a password at all, you can just use fully randomly generated key(s).
Aug
29
answered Symmetric encryption involving load balancers - can't randomize key?
Aug
23
comment ECC based Client Certificate import in Chrome/Mozilla in windows
I've found a website here that seems to test TLS with ECC with Windows based browsers.
Aug
2
comment Using authentication only one time passwords
@JimL if you regard the phone to be something you have then it is two factor authentication - but the line between one-factor and two-factor are a bit blurred here; if I retrieve the one time password (e.g. by listening in on the GSM network) then it becomes something you know - leaving only a single factor...
Aug
2
comment Using authentication only one time passwords
I think it fully depends on the use case, the threat model and attack scenarios. It apparently has enough security for many promotions where you get a unique number hidden with a product. Is it enough for online money transactions? Probably not.
Jul
30
answered Is secure web-app off-line auth possible?
Jul
13
comment End to end cryptographic methods/solutions
If you don't know for sure that both parties are online all the time then you could think about message encryption. Should we include message encryption formats like CMS, PGP and XML encryption? I think that together with SSH they are the most common formats. There are endless possibilities here though.
Feb
19
comment How to not reveal that you are using PHP?
@Matrix yes that will certainly work, and it is not far fetched at all
Feb
18
comment Strategies to store/remember very long password?
@daniel.sedlacek if I ever use a piece of text from a book or similar I always deliberately missple words, concatenatewords or leave out caracters. That avoids attacks that simply feed in the book phrase by phrase. But it is better to make up weird phrases yourself and apply these techniques.
Feb
18
comment How to not reveal that you are using PHP?
Note that these kind of settings probably won't affect persons that are able to e.g. fingerprint your server by analyzing the timing of responses. It might be pretty tricky to get around that kind of fingerprinting anyway. Maybe Rook can indicate if there is anything that can be done to make fingerprinting the server harder?
Feb
18
comment What key exchange mechanism should be used in TLS?
Darn, only a single +1 vote possible.
Jan
25
comment Can SSL requests be proxied by issuing a second certificate?
It gets a lot hairier too when you take all the credit card handling companies into account. They seem to love redirects and HTTPS sites with really stupid names. This does not do anything to earn my trust, and lets users build up confidence in trusting sites that they don't know.
Jan
25
comment Can SSL requests be proxied by issuing a second certificate?
Most of the time it is probably Alice that doesn't notice that the website is on a server with a different URL. In that case there are no issues with certificates, and the attack works. There will always be CA's willing to sell a certificate for a site whose name is close to that of another site.
Jan
13
comment Android Device Encryption
AES is not a KDF, so your question is not well defined.
Nov
2
comment Android and AES side channel attacks
Probably best asked on the Bouncy Castle mailing list, but I'm pretty sure they use a relatively safe implementation. The are certainly aware of timing attacks, e.g. "This version of the provider has been specifically reviewed to eliminate possible timing attacks on algorithms such as GCM and CCM mode."