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Stable release v32.1bitcoin/bitcoin · f0de87f04062 ↗3,020 source files · 47.5 MB stored on the server440 file guides

Release published 2026-10-28 · Snapshot fetched 2026-11-01. Latest stable release at fetch time; development branches and Git history are excluded. Only the selected code window and visible folders load here.

11,170 bytes · SHA-256 9246611ac57b427c… · View upstream ↗

1#!/usr/bin/env sage
2r"""
3Generate finite field parameters for minisketch.
4
5This script selects the finite fields used by minisketch
6 for various sizes and generates the required tables for
7 the implementation.
8
9The output (after formatting) can be found in src/fields/*.cpp.
10
11"""
12B.<b> = GF(2)
13P.<p> = B[]
14
15def apply_map(m, v):
16    r = 0
17    i = 0
18    while v != 0:
19        if (v & 1):
20            r ^^= m[i]
21        i += 1
22        v >>= 1
23    return r
24
25def recurse_moduli(acc, maxweight, maxdegree):
26    for pos in range(maxweight, maxdegree + 1, 1):
27        poly = acc + p^pos
28        if maxweight == 1:
29            if poly.is_irreducible():
30                return (pos, poly)
31        else:
32            (deg, ret) = recurse_moduli(poly, maxweight - 1, pos - 1)
33            if ret is not None:
34                return (pos, ret)
35    return (None, None)
36
37def compute_moduli(bits):
38    # Return all optimal irreducible polynomials for GF(2^bits)
39    # The result is a list of tuples (weight, degree of second-highest nonzero coefficient, polynomial)
40    maxdegree = bits - 1
41    result = []
42    for weight in range(1, bits, 2):
43        deg, res = None, None
44        while True:
45            ret = recurse_moduli(p^bits + 1, weight, maxdegree)
46            if ret[0] is not None:
47                (deg, res) = ret
48                maxdegree = deg - 1
49            else:
50                break
51        if res is not None:
52            result.append((weight + 2, deg, res))
53    return result
54
55def bits_to_int(vals):
56    ret = 0
57    base = 1
58    for val in vals:
59        ret += Integer(val) * base
60        base *= 2
61    return ret
62
63def sqr_table(f, bits, n=1):
64    ret = []
65    for i in range(bits):
66        ret.append((f^(2^n*i)).integer_representation())
67    return ret
68
69# Compute x**(2**n)
70def pow2(x, n):
71    for i in range(n):
72        x = x**2
73    return x
74
75def qrt_table(F, f, bits):
76    # Table for solving x2 + x = a
77    # This implements the technique from https://www.raco.cat/index.php/PublicacionsMatematiques/article/viewFile/37927/40412, Lemma 1
78    for i in range(bits):
79        if (f**i).trace() != 0:
80            u = f**i
81    ret = []
82    for i in range(0, bits):
83        d = f^i
84        y = sum(pow2(d, j) * sum(pow2(u, k) for k in range(j)) for j in range(1, bits))
85        ret.append(y.integer_representation() ^^ (y.integer_representation() & 1))
86    return ret
87
88def conv_tables(F, NF, bits):
89    # Generate a F(2) linear projection that maps elements from one field
90    #  to an isomorphic field with a different modulus.
91    f = F.gen()
92    fp = f.minimal_polynomial()
93    assert(fp == F.modulus())
94    nfp = fp.change_ring(NF)
95    nf = sorted(nfp.roots(multiplicities=False))[0]
96    ret = []
97    matrepr = [[B(0) for x in range(bits)] for y in range(bits)]
98    for i in range(bits):
99        val = (nf**i).integer_representation()
100        ret.append(val)
101        for j in range(bits):
102            matrepr[j][i] = B((val >> j) & 1)
103    mat = Matrix(matrepr).inverse().transpose()
104    ret2 = []
105    for i in range(bits):
106        ret2.append(bits_to_int(mat[i]))
107
108    for t in range(100):
109        f1a = F.random_element()
110        f1b = F.random_element()
111        f1r = f1a * f1b
112        f2a = NF.fetch_int(apply_map(ret, f1a.integer_representation()))
113        f2b = NF.fetch_int(apply_map(ret, f1b.integer_representation()))
114        f2r = NF.fetch_int(apply_map(ret, f1r.integer_representation()))
115        f2s = f2a * f2b
116        assert(f2r == f2s)
117
118    for t in range(100):
119        f2a = NF.random_element()
120        f2b = NF.random_element()
121        f2r = f2a * f2b
122        f1a = F.fetch_int(apply_map(ret2, f2a.integer_representation()))
123        f1b = F.fetch_int(apply_map(ret2, f2b.integer_representation()))
124        f1r = F.fetch_int(apply_map(ret2, f2r.integer_representation()))
125        f1s = f1a * f1b
126        assert(f1r == f1s)
127
128    return (ret, ret2)
129
130def fmt(i,typ):
131    if i == 0:
132        return "0"
133    else:
134        return "0x%x" % i
135
136def lintranstype(typ, bits, maxtbl):
137    gsize = min(maxtbl, bits)
138    array_size = (bits + gsize - 1) // gsize
139    bits_list = []
140    total = 0
141    for i in range(array_size):
142        rsize = (bits - total + array_size - i - 1) // (array_size - i)
143        total += rsize
144        bits_list.append(rsize)
145    return "RecLinTrans<%s, %s>" % (typ, ", ".join("%i" % x for x in bits_list))
146
147INT=0
148CLMUL=1
149CLMUL_TRI=2
150MD=3
151
152def print_modulus_md(mod):
153    ret = ""
154    pos = mod.degree()
155    for c in reversed(list(mod)):
156        if c:
157            if ret:
158                ret += " + "
159            if pos == 0:
160                ret += "1"
161            elif pos == 1:
162                ret += "x"
163            else:
164                ret += "x<sup>%i</sup>" % pos
165        pos -= 1
166    return ret
167
168def pick_modulus(bits, style):
169    # Choose the lexicographicly-first lowest-weight modulus
170    #  optionally subject to implementation specific constraints.
171    moduli = compute_moduli(bits)
172    if style == INT or style == MD:
173        multi_sqr = False
174        need_trans = False
175    elif style == CLMUL:
176        # Fast CLMUL reduction requires that bits + the highest
177        #  set bit are less than 66.
178        moduli = list(filter((lambda x: bits+x[1] <= 66), moduli)) + moduli
179        multi_sqr = True
180        need_trans = True
181        if not moduli or moduli[0][2].change_ring(ZZ)(2) == 3 + 2**bits:
182            # For modulus 3, CLMUL_TRI is obviously better.
183            return None
184    elif style == CLMUL_TRI:
185        moduli = list(filter(lambda x: bits+x[1] <= 66, moduli)) + moduli
186        moduli = list(filter(lambda x: x[0] == 3, moduli))
187        multi_sqr = True
188        need_trans = True
189    else:
190        assert(False)
191    if not moduli:
192        return None
193    return moduli[0][2]
194
195def print_result(bits, style):
196    if style == INT:
197        multi_sqr = False
198        need_trans = False
199        table_id = "%i" % bits
200    elif style == MD:
201        pass
202    elif style == CLMUL:
203        multi_sqr = True
204        need_trans = True
205        table_id = "%i" % bits
206    elif style == CLMUL_TRI:
207        multi_sqr = True
208        need_trans = True
209        table_id = "TRI%i" % bits
210    else:
211        assert(False)
212
213    nmodulus = pick_modulus(bits, INT)
214    modulus = pick_modulus(bits, style)
215    if modulus is None:
216        return
217
218    if style == MD:
219        print("* *%s*" % print_modulus_md(modulus))
220        return
221
222    if bits > 32:
223        typ = "uint64_t"
224    elif bits > 16:
225        typ = "uint32_t"
226    elif bits > 8:
227        typ = "uint16_t"
228    else:
229        typ = "uint8_t"
230
231    ttyp = lintranstype(typ, bits, 4)
232    rtyp = lintranstype(typ, bits, 6)
233
234    F.<f> = GF(2**bits, modulus=modulus)
235
236    include_table = True
237    if style != INT and style != CLMUL:
238        cmodulus = pick_modulus(bits, CLMUL)
239        if cmodulus == modulus:
240            include_table = False
241            table_id = "%i" % bits
242
243    if include_table:
244        print("typedef %s StatTable%s;" % (rtyp, table_id))
245        rtyp = "StatTable%s" % table_id
246        if (style == INT):
247            print("typedef %s DynTable%s;" % (ttyp, table_id))
248            ttyp = "DynTable%s" % table_id
249
250    if need_trans:

src/wallet/receive.cpp

src/wallet/coinselection.cpp

src/consensus/validation.h

src/primitives/transaction.cpp

src/script/descriptor.cpp

src/bitcoin-cli.cpp

src/rpc/blockchain.cpp

src/rpc/rawtransaction.cpp

src/init.cpp

src/crypto/sha256.cpp

src/consensus/merkle.h

src/consensus/tx_check.h

src/consensus/tx_verify.h

src/policy/feerate.h

src/policy/feerate.cpp

src/primitives/transaction_identifier.h

src/chainparamsbase.h

src/chainparamsbase.cpp

src/util/moneystr.cpp

src/crypto/ripemd160.h

src/crypto/sha1.h

src/crypto/sha512.h

src/crypto/hmac_sha256.h

src/crypto/hmac_sha512.h

src/crypto/hmac_sha256.cpp

src/crypto/hmac_sha512.cpp

src/crypto/hkdf_sha256_32.h

src/crypto/hkdf_sha256_32.cpp

src/support/cleanse.h

src/support/cleanse.cpp

src/crypto/siphash.cpp

src/crypto/muhash.h

src/crypto/chacha20.h

src/crypto/poly1305.h

src/crypto/chacha20poly1305.h

src/crypto/chacha20poly1305.cpp

src/util/chaintype.cpp

src/util/obfuscation.h

src/util/byte_units.h

src/util/overflow.h

src/blockencodings.cpp

src/net_permissions.cpp

src/policy/packages.cpp

src/policy/rbf.cpp

src/policy/truc_policy.cpp

src/policy/ephemeral_policy.cpp

src/policy/settings.cpp

src/policy/policy.cpp

src/node/transaction.cpp

src/node/coin.cpp

src/rpc/client.cpp

src/rpc/external_signer.cpp

src/rpc/request.cpp

src/rpc/server_util.cpp

src/rpc/fees.cpp

src/rpc/output_script.cpp

src/rpc/rawtransaction_util.cpp

src/rpc/rawtransaction_util.h

src/rpc/register.h

src/rpc/request.h

src/rpc/server_util.h

src/rpc/protocol.h

src/rpc/server.h

src/rpc/signmessage.cpp

src/rpc/txoutproof.cpp

src/rpc/util.cpp

src/rpc/util.h

src/wallet/rpc/addresses.cpp

src/wallet/rpc/backup.cpp

src/wallet/rpc/coins.cpp

src/wallet/rpc/encrypt.cpp

src/wallet/rpc/signmessage.cpp

src/wallet/rpc/util.cpp

src/wallet/rpc/util.h

src/wallet/coincontrol.cpp

src/wallet/coincontrol.h

src/wallet/context.cpp

src/wallet/context.h

src/wallet/crypter.cpp

src/wallet/crypter.h

src/wallet/db.cpp

src/wallet/export.cpp

src/wallet/external_signer_scriptpubkeyman.cpp

src/wallet/rpc/spend.cpp

src/wallet/rpc/transactions.cpp

src/wallet/rpc/wallet.cpp

src/wallet/feebumper.cpp

src/wallet/feebumper.h

src/index/base.h

src/index/base.cpp

src/index/txindex.h

src/index/txindex.cpp

src/index/txindex_key.h

src/index/txospenderindex.h

src/index/txospenderindex.cpp

src/index/blockfilterindex.h

src/index/blockfilterindex.cpp

src/index/coinstatsindex.h

src/index/coinstatsindex.cpp

src/index/db_key.h

src/index/disktxpos.h

src/kernel/chain.cpp

src/kernel/chain.h

src/kernel/checks.cpp

src/kernel/checks.h

src/kernel/context.cpp

src/kernel/context.h

src/kernel/cs_main.cpp

src/kernel/cs_main.h

src/kernel/disconnected_transactions.cpp

src/kernel/disconnected_transactions.h

src/kernel/mempool_removal_reason.cpp

src/kernel/mempool_removal_reason.h

src/kernel/coinstats.cpp

src/kernel/coinstats.h

src/kernel/chainparams.cpp

src/kernel/chainparams.h

src/wallet/sqlite.cpp

src/wallet/sqlite.h

src/wallet/transaction.cpp

src/wallet/transaction.h

src/wallet/dump.cpp

src/wallet/dump.h

src/wallet/init.cpp

src/wallet/walletutil.cpp

src/wallet/walletutil.h

src/wallet/wallettool.cpp

src/wallet/wallettool.h

src/wallet/export.h

src/wallet/migrate.cpp

src/wallet/migrate.h

src/wallet/db.h

src/wallet/walletdb.cpp

src/wallet/interfaces.cpp

src/wallet/scriptpubkeyman.cpp

src/wallet/scriptpubkeyman.h

src/kernel/bitcoinkernel.cpp

src/kernel/bitcoinkernel.h

src/kernel/bitcoinkernel_wrapper.h

src/node/chainstate.cpp

src/node/chainstate.h

src/node/blockstorage.cpp

src/node/blockstorage.h

src/node/mempool_persist.cpp

src/node/mempool_persist.h

src/node/utxo_snapshot.cpp

src/node/utxo_snapshot.h

src/node/kernel_notifications.cpp

src/node/kernel_notifications.h

src/node/blockmanager_args.cpp

src/kernel/blockmanager_opts.h

src/util/expected.cpp

src/policy/settings.h

src/util/types.h

src/kernel/messagestartchars.h

src/kernel/warning.h

src/util/exception.h

src/common/license_info.h

src/node/coins_view_args.h

src/node/database_args.h

src/util/batchpriority.h

src/util/ui_change_type.h

src/node/coins_view_args.cpp

src/node/peerman_args.h

src/util/serfloat.h

src/node/blockmanager_args.h

src/node/database_args.cpp

src/util/overloaded.h

src/interfaces/types.h

src/node/chainstatemanager_args.h

src/node/minisketchwrapper.h

src/util/macros.h

src/util/syserror.h

src/common/run_command.h

src/util/bytevectorhash.cpp

src/node/mempool_persist_args.cpp

src/util/exec.h

src/util/rbf.h

src/crypto/hex_base.h

src/node/mempool_persist_args.h

src/interfaces/echo.h

src/util/any.h

src/util/batchpriority.cpp

src/util/threadnames.h

src/node/coin.h

src/node/mempool_args.h

src/util/asmap.h

src/util/bytevectorhash.h

src/node/context.cpp

src/util/insert.h

src/util/readwritefile.h

src/node/peerman_args.cpp

src/node/interface_ui.cpp

src/interfaces/handler.h

src/node/mining_args.h

src/util/hasher.cpp

src/common/init.h

src/kernel/mempool_limits.h

src/common/system.h

src/crypto/sha3.h

src/util/threadinterrupt.cpp

src/node/protocol_version.h

src/util/exception.cpp

src/common/messages.h

src/node/connection_types.cpp

src/util/bip32.h

src/common/license_info.cpp

src/util/stdmutex.h

src/common/run_command.cpp

src/util/check.cpp

src/util/golombrice.h

src/node/types.h

src/node/timeoffsets.h

src/util/readwritefile.cpp

src/util/fastrange.h

src/util/signalinterrupt.h

src/util/task_runner.h

src/util/syserror.cpp

src/common/interfaces.cpp

src/common/types.h

src/util/threadinterrupt.h

src/kernel/chainstatemanager_opts.h

src/node/psbt.h

src/policy/ephemeral_policy.h

src/util/trace.h

src/common/url.cpp

src/kernel/mempool_options.h

src/util/serfloat.cpp

src/kernel/notifications_interface.h

src/node/timeoffsets.cpp

src/node/warnings.cpp

src/util/hash_type.h

src/crypto/hex_base.cpp

src/node/eviction.h

src/util/tokenbucket.h

src/crypto/aes.h

src/common/pcp.h

src/util/feefrac.cpp

src/node/transaction.h

src/util/threadnames.cpp

src/common/signmessage.h

src/util/exec.cpp

src/util/signalinterrupt.cpp

src/clientversion.cpp

src/common/signmessage.cpp

src/compat/assumptions.h

src/compat/byteswap.h

src/deploymentinfo.cpp

src/deploymentinfo.h

src/deploymentstatus.cpp

src/deploymentstatus.h

src/dummywallet.cpp

src/external_signer.h

src/init/bitcoin-gui.cpp

src/init/bitcoin-node.cpp

src/init/bitcoin-qt.cpp

src/init/bitcoin-wallet.cpp

src/init/bitcoind.cpp

src/init/common.h

src/interfaces/init.h

src/interfaces/ipc.h

src/key_io.h

src/logging/categories.h

src/logging/timer.h

src/mapport.h

src/musig.h

src/net_permissions.h

src/netgroup.h

src/netmessagemaker.h

src/node/chainstatemanager_args.cpp

src/node/connection_types.h

src/node/context.h

src/node/interface_ui.h

src/node/mempool_args.cpp

src/node/mining_args.cpp

src/node/minisketchwrapper.cpp

src/node/txreconciliation.h

src/policy/fees/estimator_args.cpp

src/policy/fees/estimator_args.h

src/policy/fees/estimator_man.cpp

src/policy/fees/estimator_man.h

src/policy/packages.h

src/policy/rbf.h

src/policy/truc_policy.h

src/pow.h

src/primitives/block.cpp

src/randomenv.h

src/rest.h

src/script/keyorigin.h

src/script/parsing.cpp

src/script/parsing.h

src/script/script_error.h

src/script/sigcache.cpp

src/script/sigcache.h

src/script/solver.h

src/script/verify_flags.h

src/semaphore_grant.h

src/signet.h

src/span.h

src/support/allocators/secure.h

src/support/allocators/zeroafterfree.h

src/util/tokenpipe.cpp

src/util/translation.h

src/util/vector.h

src/versionbits.h

src/versionbits_impl.h

src/wallet/external_signer_scriptpubkeyman.h

src/wallet/fees.h

src/wallet/load.h

src/wallet/receive.h

src/wallet/rpc/wallet.h

src/wallet/types.h

src/walletinitinterface.h

src/zmq/zmqabstractnotifier.cpp

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