The integrity tag has no wiki summary.
0
votes
2answers
92 views
Recommended authenticated stream cipher for minimum overhead?
I'm running my TCP/IP protocol secured by encrypting each packet with AES128/CBC, bundling a SHA256 HMAC over that packet.
This causes quite a bit of space overhead for small packets, so at first I ...
2
votes
1answer
79 views
Encrypt-then-MAC paradigm
I read that the Encrypt-then-MAC paradigm is provably secure.
From what I understand, when using for example AES for encryption and HMAC_SHA256 for MAC generation (and the keys $K_1 \neq K_2$), this ...
3
votes
1answer
177 views
CBC-MAC , fixed length, all blocks returned
CBC-MAC, with fixed length message.
Is it safe to return all ciphered blocks instead of the last?
My intuition says it is less secure, since is gives an attacker more information.
But how could one ...
1
vote
0answers
40 views
School exercise on untrusted channel comunication [duplicate]
Possible Duplicate:
Why is H(k||x) not a secure MAC construction?
I've the following problem:
two parties, A and B, share a secret key Kab.
M is a plaintext message, H an unkeyed hash ...
1
vote
1answer
101 views
Does RSA-OEAP have integrity and authenticity properties?
RSA-OAEP is IND-CCA2 secure (indistinguishable under an adaptive chosen ciphertext attack). Does it also have the INT-CTXT (integrity of ciphertext) and INT-PTXT (integrity of plaintext) properties?
...
1
vote
1answer
62 views
Ensuring integrity of a client side script
I want a script that is running on the client to compute a collision resistant hash and send it to a server. I need to ensure that the script which performs this hash is not altered in any malicious ...
4
votes
3answers
149 views
Can I jettison MAC if I already have SHA1(M)?
I'm currently using SSL with AES-CBC and HMAC for a file transfer containing string M. Now suppose Alice already knows SHA1(M) (and the adversary does not), and she downloads M from Bob using only ...
2
votes
4answers
188 views
Signature and Timestamp for Long Term Document Archival Question
I have a PDF document intended for long-term (many years, maybe decades) archival which I would like to digitally sign with my personal certificate to ensure its integrity.
As far as I understand, I ...
9
votes
1answer
185 views
Which MACs can be converted into a secure unkeyed hash function?
It is known that setting the secret key to a fixed, public value does not make MACs like CBC-MAC or GMAC into secure unkeyed cryptographic hash functions that could be used - for instance - for ...
1
vote
2answers
227 views
Is Common Name encoded in the certificate?
When I make a certificate like so
cd /etc/openvpn/easy-rsa/2.0/
source ./vars
. /etc/openvpn/easy-rsa/2.0/build-key client1
Then ...
3
votes
1answer
136 views
Is a using salt important when creating a hash data validator?
I am creating a service that will return an set of objects, which will be used by multiple systems. At the end of the process, one (or more) of the objects will be sent back to our system for ...
