amaclin (OP)
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November 28, 2014, 08:00:45 AM Last edit: November 28, 2014, 08:48:09 AM by amaclin |
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In few words signing in ECDSA is (some pseudocode)
int256 r, s, digest, privkey, k; k = rand ( ); [r,s] = sign ( privkey, digest, k ); // signing
The question: is it possible to get 'k' from other values if i know them and do not know 'k' (formula, not bruteforcing)? Something like
k = get_k_value ( privkey, digest, r, s );
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gmaxwell
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November 28, 2014, 09:03:18 AM |
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Yes, if you know the private key. What awful thing are you doing?
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amaclin (OP)
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November 28, 2014, 09:10:00 AM Last edit: November 28, 2014, 09:59:26 AM by amaclin |
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Yes, if you know the private key. What awful thing are you doing?
Stealing bitcoins as usual What else can we do on Sunday? {*}
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hhanh00
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November 28, 2014, 11:11:08 AM |
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K=(digest+r.privkey)/s mod n
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BitCoinDream
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The revolution will be digital
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November 29, 2014, 08:46:30 PM |
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K=(digest+r.privkey)/s mod n
What is n ?
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amaclin (OP)
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November 29, 2014, 09:18:00 PM |
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What is n ? n = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141
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dabura667
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November 30, 2014, 02:39:01 AM |
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What is n ? n = 0xFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFFEBAAEDCE6AF48A03BBFD25E8CD0364141 aka "the order of the curve" of secp256k1 (the curve bitcoin uses)
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My Tip Address: 1DXcHTJS2DJ3xDoxw22wCt11FeAsgfzdBU
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hhanh00
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November 30, 2014, 06:31:31 AM |
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This also allows you to calculate the public key from the signature.
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dabura667
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November 30, 2014, 08:45:29 AM |
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This also allows you to calculate the public key from the signature.
lol. If you know the private key, you don't need the signature to calculate the public key.
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My Tip Address: 1DXcHTJS2DJ3xDoxw22wCt11FeAsgfzdBU
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gmaxwell
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November 30, 2014, 09:33:30 AM |
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This also allows you to calculate the public key from the signature.
The public key is not completely unambiguous from the signature. (nor is R, technically)
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hhanh00
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November 30, 2014, 10:21:00 AM |
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lol. If you know the private key, you don't need the signature to calculate the public key.
Obviously without knowing the private key. The public key is not completely unambiguous from the signature. (nor is R, technically)
Yes but it can be lifted if we know the address.
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