From d4f20da7696c8b266e7fb5a02afc0ae4f067f50f Mon Sep 17 00:00:00 2001 From: Finrod Felagund Date: Thu, 5 Sep 2024 22:20:28 +0200 Subject: implement bech32 encoding from nip19 --- CMakeLists.txt | 1 + include/nostr.hpp | 12 +++++ scripts/bech.py | 144 ++++++++++++++++++++++++++++++++++++++++++++++++++++++ scripts/bech32.py | 84 +++++++++++++++++++++++++++++++ src/bech32.cpp | 18 +++++++ 5 files changed, 259 insertions(+) create mode 100644 scripts/bech.py create mode 100644 scripts/bech32.py create mode 100644 src/bech32.cpp diff --git a/CMakeLists.txt b/CMakeLists.txt index 744eccf..67fb256 100644 --- a/CMakeLists.txt +++ b/CMakeLists.txt @@ -61,6 +61,7 @@ set(CLIENT_SOURCE_DIR ./src/client) set(SOURCES ${SOURCE_DIR}/event.cpp ${SOURCE_DIR}/filters.cpp + ${SOURCE_DIR}/bech32.cpp ${SOURCE_DIR}/nostr_service.cpp ${CLIENT_SOURCE_DIR}/websocketpp_client.cpp ) diff --git a/include/nostr.hpp b/include/nostr.hpp index e699f21..e8409b0 100644 --- a/include/nostr.hpp +++ b/include/nostr.hpp @@ -342,4 +342,16 @@ public: */ virtual void sign(std::shared_ptr event) = 0; }; + +class IBech32 +{ + virtual void encode(char*, uint8_t*) = 0; + virtual void encode(char*, char*) = 0; + virtual void encode(std::string, std::string) = 0; + virtual void encode(std::string, std::vector) = 0; + + virtual void decode(char*) = 0; + virtual void decode(std::string) = 0; +}; + } // namespace nostr diff --git a/scripts/bech.py b/scripts/bech.py new file mode 100644 index 0000000..b2e3dcb --- /dev/null +++ b/scripts/bech.py @@ -0,0 +1,144 @@ +# Copyright (c) 2017 Pieter Wuille +# +# Permission is hereby granted, free of charge, to any person obtaining a copy +# of this software and associated documentation files (the "Software"), to deal +# in the Software without restriction, including without limitation the rights +# to use, copy, modify, merge, publish, distribute, sublicense, and/or sell +# copies of the Software, and to permit persons to whom the Software is +# furnished to do so, subject to the following conditions: +# +# The above copyright notice and this permission notice shall be included in +# all copies or substantial portions of the Software. +# +# THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR +# IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY, +# FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE +# AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER +# LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, +# OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN +# THE SOFTWARE. + +"""Reference implementation for Bech32 and segwit addresses.""" + +from typing import Iterable, List, Optional, Tuple, Union +import hashlib + +CHARSET = "qpzry9x8gf2tvdw0s3jn54khce6mua7l" + + +def bech32_polymod(values: Iterable[int]) -> int: + """Internal function that computes the Bech32 checksum.""" + generator = [0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3] + chk = 1 + for value in values: + top = chk >> 25 + chk = (chk & 0x1ffffff) << 5 ^ value + for i in range(5): + chk ^= generator[i] if ((top >> i) & 1) else 0 + return chk + + +def bech32_hrp_expand(hrp: str) -> List[int]: + """Expand the HRP into values for checksum computation.""" + return [ord(x) >> 5 for x in hrp] + [0] + [ord(x) & 31 for x in hrp] + + +def bech32_verify_checksum(hrp: str, data: Iterable[int]) -> bool: + """Verify a checksum given HRP and converted data characters.""" + return bech32_polymod(bech32_hrp_expand(hrp) + list(data)) == 1 + + +def bech32_create_checksum(hrp: str, data: Iterable[int]) -> List[int]: + """Compute the checksum values given HRP and data.""" + values = bech32_hrp_expand(hrp) + list(data) + polymod = bech32_polymod(values + [0, 0, 0, 0, 0, 0]) ^ 1 + return [(polymod >> 5 * (5 - i)) & 31 for i in range(6)] + + +def bech32_encode(hrp: str, data: Iterable[int]) -> str: + """Compute a Bech32 string given HRP and data values.""" + combined = list(data) + bech32_create_checksum(hrp, data) + return hrp + "1" + "".join([CHARSET[d] for d in combined]) + + +def bech32_decode(bech: str) -> Union[Tuple[None, None], Tuple[str, List[int]]]: + """Validate a Bech32 string, and determine HRP and data.""" + if (any(ord(x) < 33 or ord(x) > 126 for x in bech)) or ( + bech.lower() != bech and bech.upper() != bech + ): + return (None, None) + bech = bech.lower() + pos = bech.rfind("1") + if pos < 1 or pos > 83 or pos + 7 > len(bech): # or len(bech) > 90: + return (None, None) + if not all(x in CHARSET for x in bech[pos + 1 :]): + return (None, None) + hrp = bech[:pos] + data = [CHARSET.find(x) for x in bech[pos + 1 :]] + if not bech32_verify_checksum(hrp, data): + return (None, None) + return (hrp, data[:-6]) + + +def convertbits(data: Iterable[int], frombits: int, tobits: int, pad: bool = True) -> Optional[List[int]]: + """General power-of-2 base conversion.""" + acc = 0 + bits = 0 + ret = [] + maxv = (1 << tobits) - 1 + max_acc = (1 << (frombits + tobits - 1)) - 1 + for value in data: + if value < 0 or (value >> frombits): + return None + acc = ((acc << frombits) | value) & max_acc + bits += frombits + while bits >= tobits: + bits -= tobits + ret.append((acc >> bits) & maxv) + if pad: + if bits: + ret.append((acc << (tobits - bits)) & maxv) + elif bits >= frombits or ((acc << (tobits - bits)) & maxv): + return None + return ret + + +def decode(hrp: str, addr: str) -> Union[Tuple[None, None], Tuple[int, List[int]]]: + """Decode a segwit address.""" + hrpgot, data = bech32_decode(addr) + if hrpgot != hrp: + return (None, None) + assert data is not None + decoded = convertbits(data[1:], 5, 8, False) + if decoded is None or len(decoded) < 2 or len(decoded) > 40: + return (None, None) + if data[0] > 16: + return (None, None) + if data[0] == 0 and len(decoded) != 20 and len(decoded) != 32: + return (None, None) + return (data[0], decoded) + + +def encode(hrp: str, witver: int, witprog: Iterable[int]) -> Optional[str]: + """Encode a segwit address.""" + five_bit_witprog = convertbits(witprog, 8, 5) + if five_bit_witprog is None: + return None + ret = bech32_encode(hrp, [witver] + five_bit_witprog) + if decode(hrp, ret) == (None, None): + return None + return ret + + + +pubkey = "3bf0c63fcb93463407af97a5e5ee64fa883d107ef9e558472c4eb9aaaefa459d" +squashed = convertbits(bytes.fromhex(pubkey), 8, 5) +print(bech32_encode("npub", squashed) == "npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6") +print(bech32_verify_checksum("npub", squashed)) + +hrp, data = bech32_decode("npub180cvv07tjdrrgpa0j7j7tmnyl2yr6yr7l8j4s3evf6u64th6gkwsyjh6w6") +data8bits = convertbits(data, 5, 8)[:-1] + +reconstructed = bytes(data8bits).hex() +print(reconstructed) +print(pubkey) \ No newline at end of file diff --git a/scripts/bech32.py b/scripts/bech32.py new file mode 100644 index 0000000..6851efc --- /dev/null +++ b/scripts/bech32.py @@ -0,0 +1,84 @@ +import hashlib +from typing import Iterable, List, Optional, Tuple, Union + +BECH32A_ALPHABET = "qpzry9x8gf2tvdw0s3jn54khce6mua7l" + +def convertbits(data: Iterable[int], frombits: int, tobits: int, pad: bool = True) -> Optional[List[int]]: + """General power-of-2 base conversion.""" + acc = 0 + bits = 0 + ret = [] + maxv = (1 << tobits) - 1 + max_acc = (1 << (frombits + tobits - 1)) - 1 + + print(f"maxv: {maxv}") + print(f"max_acc: {max_acc}") + + for value in data: + if value < 0 or (value >> frombits): + return None + acc = ((acc << frombits) | value) & max_acc + bits += frombits + while bits >= tobits: + bits -= tobits + ret.append((acc >> bits) & maxv) + if pad: + if bits: + ret.append((acc << (tobits - bits)) & maxv) + elif bits >= frombits or ((acc << (tobits - bits)) & maxv): + return None + return ret + +def bech32_polymod(values): + GEN = [0x3b6a57b2, 0x26508e6d, 0x1ea119fa, 0x3d4233dd, 0x2a1462b3] + chk = 1 + for v in values: + b = (chk >> 25) + chk = (chk & 0x1ffffff) << 5 ^ v + for i in range(5): + chk ^= GEN[i] if ((b >> i) & 1) else 0 + return chk + +def bech32_hrp_expand(s): + return [ord(x) >> 5 for x in s] + [0] + [ord(x) & 31 for x in s] + +def bech32_verify_checksum(hrp, data): + polymod = bech32_polymod(bech32_hrp_expand(hrp) + data) + print("polymod", polymod) + return polymod == 1 + +def bech32_create_checksum(hrp, data): + values = bech32_hrp_expand(hrp) + data + polymod = bech32_polymod(values + [0,0,0,0,0,0]) ^ 1 + return [(polymod >> 5 * (5 - i)) & 31 for i in range(6)] + + +pubkey = 0x0279be667ef9dcbbac55a06295ce870b07029bfcdb2dce28d959f2815b16f81798 + + +sha256 = hashlib.sha256() +sha256.update(pubkey.to_bytes(length=33)) + +sha265_pubkey = sha256.hexdigest() +print(sha265_pubkey) + +ripemd160 = hashlib.new('ripemd160') +ripemd160.update(sha256.digest()) +riped_sha256_pubkey = ripemd160.digest() +print(ripemd160.hexdigest()) + +squashed = convertbits(riped_sha256_pubkey, 8, 5) +squashed.insert(0, 0) + +checksum = bech32_create_checksum(hrp="bc", data=squashed) +print(checksum) +squashed.extend(checksum) + +encoded = "" +print(squashed) +for i in squashed: + encoded += BECH32A_ALPHABET[i] + +bech32_addr = "bc" + "1" + encoded +print(bech32_addr) +assert bech32_addr == "bc1qw508d6qejxtdg4y5r3zarvary0c5xw7kv8f3t4" \ No newline at end of file diff --git a/src/bech32.cpp b/src/bech32.cpp new file mode 100644 index 0000000..c97bd42 --- /dev/null +++ b/src/bech32.cpp @@ -0,0 +1,18 @@ +#include + +namespace nostr +{ +class Bech32 : public IBech32 +{ + public: + void encode(char *hrp, uint8_t *data) override {} + void encode(char *hrp, char *data) override {} + void encode(std::string hrp, std::string data) override {} + void encode(std::string hrp, std::vector data) override {} + + private: + void create_checksum() {} + +}; + +} \ No newline at end of file -- cgit