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- #Smok quantum error no secret key how to#
- #Smok quantum error no secret key full#
- #Smok quantum error no secret key mac#
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#Smok quantum error no secret key full#
You could append the secret to timestamp instead of pre-pending but in general you are better off using HMAC with SHA1 digest (HMAC is just construction and can use MD5 or SHA as digest algorithms).įinally, you are signing just the timestamp and the not the full request.
#Smok quantum error no secret key mac#
This is not an issue with just timestamp but it is an issue when you compute MAC over messages of arbitrary length. Finding m1, given h(m1) is still computationally infeasible.Īlso, you are using a MAC (message authentication code), so an attacker can't forget a message without knowing secret with one caveat - the general MAC construction that you used is susceptible to length extension attack - an attacker can in some circumstances forge a message m2|m3, h(secret, m2|m3) given m2, h(secret, m2). Note that the best attacks against MD5 and SHA-1 have been about finding any two arbitrary messages m1 and m2 where h(m1) = h(m2) or finding m2 such that h(m1) = h(m2) and m1 != m2. So there is, fundamentally, no way to reverse the hash with any certainty. although the timestamps are different, they generate the same hash. Of course two or more timestamps within the range you examine might 'collide' i.e. This the industry standard and secure way of authenticating messages, whether they are encrypted or not.Ī hash is a one-way function, meaning that many inputs all produce the same output.Īs you know the secret, and you can make a sensible guess as to the range of the timestamp, then you could iterate over all those timestamps, compute the hash and compare it. The message sequence id is a simple counter to keep track by both parties to the number of messages they have exchanged in this 'session' - this prevents an attacker from simply replaying previous-seen messages. You have: msg,hmac("My Secret Key",sha(msg+msg_sequence_id)) So instead of your: sha1("My Secret Key"+"a timestamp") You send the message plaintext as well as an accompanying hash of that message where your secret has been mixed in. The standard why to do this is to use a message digest, e.g.
#Smok quantum error no secret key how to#
The question is actually how to authenticate over an insecure session.
![smok quantum error no secret key smok quantum error no secret key](https://img2018.cnblogs.com/blog/1617125/201907/1617125-20190711171341775-1020512025.png)
An attacker would try to go after the key (either but brute-force guessing or by trying to get it from your device) rather than trying to break SHA-1. The security of your whole system would rely on this shared secret (because both sender and receiver need to know, but no one else).
![smok quantum error no secret key smok quantum error no secret key](https://i.stack.imgur.com/1e6GL.png)
If a brute force attack is feasible depends on the length of your secret key. You also need to additionally transmit the timestamp in the clear, because otherwise you have no way to verify the digest (other than trying a lot of plausible timestamps). sha("My Secret Key"+"a timestamp" + the whole message to be signed) Otherwise a man-in-the-middle could intercept the message, and use the signature (which only contains the sender's key and the timestamp) to attach it to a fake message (where it would still be valid).Īnd you should probably be using SHA-256 for new systems now. What you should definitely be doing though, is include the message that is being transmitted into the hash calculation. No, you cannot reverse SHA-1, that is exactly why it is called a Secure Hash Algorithm.