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6

asymmetric ciphers Ones based on specific primitives, like RSA and ECDSA specifically. Symmetric algorithms are supposed to be safe. With approximately half the number of bits of security due to Grover's algorithm. Which components of the bitcoin blockchain would be exposed to quantum attacks? The security of SHA256 would be halved, ECDSA would be ...


2

Conversion from a HD seed to a master private key is specified by BIP 32. It is done by computing a HMAC-SHA512 where the key is the text Bitcoin seed and the data is the HD seed itself. The first 32 bytes (256 bits) is the master private key. The last 32 byte is the chaincode for the master key.


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It depends a lot on the kind of locking condition you want to satisfy. The addresses that you have mentioned would depict 'standard' locking condition where the user reveals their public key and associated signature in order to spend the locked bitcoins. However, you can create custom scripts and then convert them into standard addresses. For example, ...


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A private key starting with a 6... and being 58 characters long.. sounds to me like you encrypted another private key with BIP38? Simply decode the private key using a third party tool and then import the decrypted private key into ElectrumSV. consider the following private key; L4GPduQvHAhFrpnF5x29N7UV8x5iLqxKRWArfHvJn4PwtZu35Uur and subsequent adress - ...


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As other's have said, the essential point is the algebraic definition for additive inverses in elliptic arithemetic. -(x,y)=(x,-y) But if it helps, there are also some nice geometric illustrations like this one from Vitalik Buterin's Exploring Elliptic Curve Pairings: Suppose R = (x,y). Since the elliptic curve is symmetric with respect to the x-axis, we ...


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Here is the sample of code for subtraction of two points. # -*- coding: utf-8 -*- def OnCurve(x,y): # Check if the point is on the curve A = (y*y)%P B = (x*x*x)%P C = False if A == (B + 7): C = True return C def ECadd(xp,yp,xq,yq): # EC point addition m = ((yq-yp) * modinv(xq-xp,P))%P xr = (m*m-xp-xq)%P yr = (m*(xp-...


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You can negate a point (x, y) by simply changing it to (x, −y). The document that defines ECDSA reminds us of this fact: https://www.secg.org/sec1-v2.pdf Here's a screenshot: So once you have negated one of your points, just add it to the other one, and you have achieved subtraction.


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It looks like doing such a conversion is not well supported, nor is instantiating a private key as uncompressed unless you do so with a WIF key. However, you can change the compressed-ness by doing: key._public_key = key._pk.public_key.format(compressed=False) But this requires you do to this immediately after instantiation as otherwise precomputed ...


3

A single private key can lead to different addresses, depending on the script it is used in - These include p2pkh, p2wpkh, p2sh-p2wpkh. Electrum prepends the script type to the private key during export and import so that it knows which address to derive and check for outputs on.


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