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2

transferring public keys over the wire to maybe a TLS or SSH implementation but also importing and exporting of keys generated using other tools. TLS has its own wire formats for ephemeral publickeys, following the encoding style used in the rest of TLS. For (updated) 1.2 and below see rfc8422 5.4 (and 5.4.1) which has a now-obsolete 1-byte format specifier,...


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For the private key, it's common to use PKCS#8, which is a container format - a header specifying the type of the key (RSA? ECC? Which ECC curve?) and the key itself. The key itself is specified in section C.4 of SEC 1. Everything here is encoded in ASN.1 DER (DER is a concrete encoding of the abstract ASN.1 encoding), which can be saved in raw binary format ...


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I am not 100% sure when you say "exchange the keys from one to other system". This is how i would do it. Assuming You have two HSM's (Thales-A, Safenet-B) 1. Create a ZMK at one of HSM and import it in other HSM's using console commands. Once you do this you will have clear ZMK ,"ZMK encrypted under A's LMK" call it ZMK_A and "ZMK ...


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Do secret keys get expired, or just the public key gets expired? The private key does not expire. A public key expires, but only in the sense that the certificate(s) part of it expires. The public key value does not change when a renewed public key is issued. Do I have to back up the master sec key each time I renew it? No. Also, only the public key (or ...


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Password cracking evolves pretty quickly, so in general you should always question the defaults of any library. In this case, I think you can use the export_key() function, but with a more modern password derivation algorithm like scrypt: key.export_key(pkcs=8, protection='scryptAndAES256-CBC', passphrase='my secret') This will still use the default scrypt ...


2

Well, it's sort of secure. There are no serious issues, but there are a few problems: 3DES - A cipher composed of three rounds of the DES cipher. DES has a key size much too low at only 56 bits, but running it three times (first in the encryption direction, then the decryption direction, then the encryption again, hence the acronym "EDE") brings ...


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See this explanation. The 0x10 signature (typically belonging to a different individual) is applied to one's master/primary key, not to 0x18 subkey signature packets used for signing, encrypting, and authenticating. Remember, CA responsibilities are decentralized with the PGP Web of Trust and the one's master/primary key can be used to sign other people's ...


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For the discrete case, you can just use any zk-SNARK that generalizes over arithmetic circuits. There is no direct way to do a zero-knowledge proof over the reals. However, you can map linear operations over real numbers to operations in the field you are working in by first proving an upper bound on your inputs. Since the circuit is public the verifier can ...


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There is no point multiplication operation on secure elliptic curves*, there is only scalar multiplication apart from the point addition of the group. Scalar multiplication Scalar multiplication with a scalar $t$ is adding a point $P$ it self $t$-times $$ [t]P : = \underbrace{P + P + \cdots + P}_{t-times}$$ and it is well defined operation since the group is ...


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A DES key is 56 bits long or 8 ASCII(7 bit) characters. The rsa public key n must be larger than that. However RSA key only barely big enough to hold a DES key would give almost no security at all. Common RSA key lengths today are 2048 or even 4096 bits long. 512bit RSA keys which used to be reasonably common can now be broken in minutes with commercially ...


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The exercise fails to cover how a sender is supposed to know the Id of an intended recipient, and how the CE is supposed to know that a KiPub it gets is that of the Mi with this Id. If the goal is just to get away with a high mark, ignore the issue or briefly mention we assume sender knows Id; and CE knows Id and KiPubwith, and acts honestly. Never insist ...


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How to calculate number of possible key pairs in RSA Well, if we bound the acceptable $e, d$ values to, say, $(0, \phi(n))$ (as I pointed out in the comments, if we don't have such a bound, then the number of such pairs is infinite), then the number of such pairs is: $$(\gcd( p-1, q-1))^2 \cdot \phi( \lambda( n))$$ Or possibly one less, if you arbitrarily ...


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