58 lines
1.9 KiB
Python
58 lines
1.9 KiB
Python
# MIT License
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#
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# Copyright (c) 2015 Brian Warner and other contributors
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# Permission is hereby granted, free of charge, to any person obtaining a copy
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# of this software and associated documentation files (the "Software"), to deal
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# in the Software without restriction, including without limitation the rights
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# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
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# copies of the Software, and to permit persons to whom the Software is
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# furnished to do so, subject to the following conditions:
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#
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# The above copyright notice and this permission notice shall be included in all
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# copies or substantial portions of the Software.
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#
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# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
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# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
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# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
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# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
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# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
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# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
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# SOFTWARE.
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from . import eddsa
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class BadSignatureError(Exception):
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pass
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SECRETKEYBYTES = 64
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PUBLICKEYBYTES = 32
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SIGNATUREKEYBYTES = 64
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def publickey(seed32):
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assert len(seed32) == 32
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vk32 = eddsa.publickey(seed32)
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return vk32, seed32+vk32
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def sign(msg, skvk):
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assert len(skvk) == 64
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sk = skvk[:32]
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vk = skvk[32:]
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sig = eddsa.signature(msg, sk, vk)
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return sig+msg
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def open(sigmsg, vk):
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assert len(vk) == 32
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sig = sigmsg[:64]
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msg = sigmsg[64:]
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try:
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valid = eddsa.checkvalid(sig, msg, vk)
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except ValueError as e:
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raise BadSignatureError(e)
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except Exception as e:
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if str(e) == "decoding point that is not on curve":
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raise BadSignatureError(e)
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raise
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if not valid:
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raise BadSignatureError()
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return msg |