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Diffstat (limited to 'src/script/miniscript.cpp')
-rw-r--r-- | src/script/miniscript.cpp | 349 |
1 files changed, 349 insertions, 0 deletions
diff --git a/src/script/miniscript.cpp b/src/script/miniscript.cpp new file mode 100644 index 0000000000..019f02f159 --- /dev/null +++ b/src/script/miniscript.cpp @@ -0,0 +1,349 @@ +// Copyright (c) 2019 The Bitcoin Core developers +// Distributed under the MIT software license, see the accompanying +// file COPYING or http://www.opensource.org/licenses/mit-license.php. + +#include <string> +#include <vector> +#include <script/script.h> +#include <script/standard.h> +#include <script/miniscript.h> + +#include <assert.h> + +namespace miniscript { +namespace internal { + +Type SanitizeType(Type e) { + int num_types = (e << "K"_mst) + (e << "V"_mst) + (e << "B"_mst) + (e << "W"_mst); + if (num_types == 0) return ""_mst; // No valid type, don't care about the rest + assert(num_types == 1); // K, V, B, W all conflict with each other + bool ok = // Work around a GCC 4.8 bug that breaks user-defined literals in macro calls. + (!(e << "z"_mst) || !(e << "o"_mst)) && // z conflicts with o + (!(e << "n"_mst) || !(e << "z"_mst)) && // n conflicts with z + (!(e << "n"_mst) || !(e << "W"_mst)) && // n conflicts with W + (!(e << "V"_mst) || !(e << "d"_mst)) && // V conflicts with d + (!(e << "K"_mst) || (e << "u"_mst)) && // K implies u + (!(e << "V"_mst) || !(e << "u"_mst)) && // V conflicts with u + (!(e << "e"_mst) || !(e << "f"_mst)) && // e conflicts with f + (!(e << "e"_mst) || (e << "d"_mst)) && // e implies d + (!(e << "V"_mst) || !(e << "e"_mst)) && // V conflicts with e + (!(e << "d"_mst) || !(e << "f"_mst)) && // d conflicts with f + (!(e << "V"_mst) || (e << "f"_mst)) && // V implies f + (!(e << "K"_mst) || (e << "s"_mst)) && // K implies s + (!(e << "z"_mst) || (e << "m"_mst)); // z implies m + assert(ok); + return e; +} + +Type ComputeType(Fragment nodetype, Type x, Type y, Type z, const std::vector<Type>& sub_types, uint32_t k, size_t data_size, size_t n_subs, size_t n_keys) { + // Sanity check on data + if (nodetype == Fragment::SHA256 || nodetype == Fragment::HASH256) { + assert(data_size == 32); + } else if (nodetype == Fragment::RIPEMD160 || nodetype == Fragment::HASH160) { + assert(data_size == 20); + } else { + assert(data_size == 0); + } + // Sanity check on k + if (nodetype == Fragment::OLDER || nodetype == Fragment::AFTER) { + assert(k >= 1 && k < 0x80000000UL); + } else if (nodetype == Fragment::MULTI) { + assert(k >= 1 && k <= n_keys); + } else if (nodetype == Fragment::THRESH) { + assert(k >= 1 && k <= n_subs); + } else { + assert(k == 0); + } + // Sanity check on subs + if (nodetype == Fragment::AND_V || nodetype == Fragment::AND_B || nodetype == Fragment::OR_B || + nodetype == Fragment::OR_C || nodetype == Fragment::OR_I || nodetype == Fragment::OR_D) { + assert(n_subs == 2); + } else if (nodetype == Fragment::ANDOR) { + assert(n_subs == 3); + } else if (nodetype == Fragment::WRAP_A || nodetype == Fragment::WRAP_S || nodetype == Fragment::WRAP_C || + nodetype == Fragment::WRAP_D || nodetype == Fragment::WRAP_V || nodetype == Fragment::WRAP_J || + nodetype == Fragment::WRAP_N) { + assert(n_subs == 1); + } else if (nodetype != Fragment::THRESH) { + assert(n_subs == 0); + } + // Sanity check on keys + if (nodetype == Fragment::PK_K || nodetype == Fragment::PK_H) { + assert(n_keys == 1); + } else if (nodetype == Fragment::MULTI) { + assert(n_keys >= 1 && n_keys <= 20); + } else { + assert(n_keys == 0); + } + + // Below is the per-nodetype logic for computing the expression types. + // It heavily relies on Type's << operator (where "X << a_mst" means + // "X has all properties listed in a"). + switch (nodetype) { + case Fragment::PK_K: return "Konudemsxk"_mst; + case Fragment::PK_H: return "Knudemsxk"_mst; + case Fragment::OLDER: return + "g"_mst.If(k & CTxIn::SEQUENCE_LOCKTIME_TYPE_FLAG) | + "h"_mst.If(!(k & CTxIn::SEQUENCE_LOCKTIME_TYPE_FLAG)) | + "Bzfmxk"_mst; + case Fragment::AFTER: return + "i"_mst.If(k >= LOCKTIME_THRESHOLD) | + "j"_mst.If(k < LOCKTIME_THRESHOLD) | + "Bzfmxk"_mst; + case Fragment::SHA256: return "Bonudmk"_mst; + case Fragment::RIPEMD160: return "Bonudmk"_mst; + case Fragment::HASH256: return "Bonudmk"_mst; + case Fragment::HASH160: return "Bonudmk"_mst; + case Fragment::JUST_1: return "Bzufmxk"_mst; + case Fragment::JUST_0: return "Bzudemsxk"_mst; + case Fragment::WRAP_A: return + "W"_mst.If(x << "B"_mst) | // W=B_x + (x & "ghijk"_mst) | // g=g_x, h=h_x, i=i_x, j=j_x, k=k_x + (x & "udfems"_mst) | // u=u_x, d=d_x, f=f_x, e=e_x, m=m_x, s=s_x + "x"_mst; // x + case Fragment::WRAP_S: return + "W"_mst.If(x << "Bo"_mst) | // W=B_x*o_x + (x & "ghijk"_mst) | // g=g_x, h=h_x, i=i_x, j=j_x, k=k_x + (x & "udfemsx"_mst); // u=u_x, d=d_x, f=f_x, e=e_x, m=m_x, s=s_x, x=x_x + case Fragment::WRAP_C: return + "B"_mst.If(x << "K"_mst) | // B=K_x + (x & "ghijk"_mst) | // g=g_x, h=h_x, i=i_x, j=j_x, k=k_x + (x & "ondfem"_mst) | // o=o_x, n=n_x, d=d_x, f=f_x, e=e_x, m=m_x + "us"_mst; // u, s + case Fragment::WRAP_D: return + "B"_mst.If(x << "Vz"_mst) | // B=V_x*z_x + "o"_mst.If(x << "z"_mst) | // o=z_x + "e"_mst.If(x << "f"_mst) | // e=f_x + (x & "ghijk"_mst) | // g=g_x, h=h_x, i=i_x, j=j_x, k=k_x + (x & "ms"_mst) | // m=m_x, s=s_x + // NOTE: 'd:' is not 'u' under P2WSH as MINIMALIF is only a policy rule there. + "ndx"_mst; // n, d, x + case Fragment::WRAP_V: return + "V"_mst.If(x << "B"_mst) | // V=B_x + (x & "ghijk"_mst) | // g=g_x, h=h_x, i=i_x, j=j_x, k=k_x + (x & "zonms"_mst) | // z=z_x, o=o_x, n=n_x, m=m_x, s=s_x + "fx"_mst; // f, x + case Fragment::WRAP_J: return + "B"_mst.If(x << "Bn"_mst) | // B=B_x*n_x + "e"_mst.If(x << "f"_mst) | // e=f_x + (x & "ghijk"_mst) | // g=g_x, h=h_x, i=i_x, j=j_x, k=k_x + (x & "oums"_mst) | // o=o_x, u=u_x, m=m_x, s=s_x + "ndx"_mst; // n, d, x + case Fragment::WRAP_N: return + (x & "ghijk"_mst) | // g=g_x, h=h_x, i=i_x, j=j_x, k=k_x + (x & "Bzondfems"_mst) | // B=B_x, z=z_x, o=o_x, n=n_x, d=d_x, f=f_x, e=e_x, m=m_x, s=s_x + "ux"_mst; // u, x + case Fragment::AND_V: return + (y & "KVB"_mst).If(x << "V"_mst) | // B=V_x*B_y, V=V_x*V_y, K=V_x*K_y + (x & "n"_mst) | (y & "n"_mst).If(x << "z"_mst) | // n=n_x+z_x*n_y + ((x | y) & "o"_mst).If((x | y) << "z"_mst) | // o=o_x*z_y+z_x*o_y + (x & y & "dmz"_mst) | // d=d_x*d_y, m=m_x*m_y, z=z_x*z_y + ((x | y) & "s"_mst) | // s=s_x+s_y + "f"_mst.If((y << "f"_mst) || (x << "s"_mst)) | // f=f_y+s_x + (y & "ux"_mst) | // u=u_y, x=x_y + ((x | y) & "ghij"_mst) | // g=g_x+g_y, h=h_x+h_y, i=i_x+i_y, j=j_x+j_y + "k"_mst.If(((x & y) << "k"_mst) && + !(((x << "g"_mst) && (y << "h"_mst)) || + ((x << "h"_mst) && (y << "g"_mst)) || + ((x << "i"_mst) && (y << "j"_mst)) || + ((x << "j"_mst) && (y << "i"_mst)))); // k=k_x*k_y*!(g_x*h_y + h_x*g_y + i_x*j_y + j_x*i_y) + case Fragment::AND_B: return + (x & "B"_mst).If(y << "W"_mst) | // B=B_x*W_y + ((x | y) & "o"_mst).If((x | y) << "z"_mst) | // o=o_x*z_y+z_x*o_y + (x & "n"_mst) | (y & "n"_mst).If(x << "z"_mst) | // n=n_x+z_x*n_y + (x & y & "e"_mst).If((x & y) << "s"_mst) | // e=e_x*e_y*s_x*s_y + (x & y & "dzm"_mst) | // d=d_x*d_y, z=z_x*z_y, m=m_x*m_y + "f"_mst.If(((x & y) << "f"_mst) || (x << "sf"_mst) || (y << "sf"_mst)) | // f=f_x*f_y + f_x*s_x + f_y*s_y + ((x | y) & "s"_mst) | // s=s_x+s_y + "ux"_mst | // u, x + ((x | y) & "ghij"_mst) | // g=g_x+g_y, h=h_x+h_y, i=i_x+i_y, j=j_x+j_y + "k"_mst.If(((x & y) << "k"_mst) && + !(((x << "g"_mst) && (y << "h"_mst)) || + ((x << "h"_mst) && (y << "g"_mst)) || + ((x << "i"_mst) && (y << "j"_mst)) || + ((x << "j"_mst) && (y << "i"_mst)))); // k=k_x*k_y*!(g_x*h_y + h_x*g_y + i_x*j_y + j_x*i_y) + case Fragment::OR_B: return + "B"_mst.If(x << "Bd"_mst && y << "Wd"_mst) | // B=B_x*d_x*W_x*d_y + ((x | y) & "o"_mst).If((x | y) << "z"_mst) | // o=o_x*z_y+z_x*o_y + (x & y & "m"_mst).If((x | y) << "s"_mst && (x & y) << "e"_mst) | // m=m_x*m_y*e_x*e_y*(s_x+s_y) + (x & y & "zse"_mst) | // z=z_x*z_y, s=s_x*s_y, e=e_x*e_y + "dux"_mst | // d, u, x + ((x | y) & "ghij"_mst) | // g=g_x+g_y, h=h_x+h_y, i=i_x+i_y, j=j_x+j_y + (x & y & "k"_mst); // k=k_x*k_y + case Fragment::OR_D: return + (y & "B"_mst).If(x << "Bdu"_mst) | // B=B_y*B_x*d_x*u_x + (x & "o"_mst).If(y << "z"_mst) | // o=o_x*z_y + (x & y & "m"_mst).If(x << "e"_mst && (x | y) << "s"_mst) | // m=m_x*m_y*e_x*(s_x+s_y) + (x & y & "zes"_mst) | // z=z_x*z_y, e=e_x*e_y, s=s_x*s_y + (y & "ufd"_mst) | // u=u_y, f=f_y, d=d_y + "x"_mst | // x + ((x | y) & "ghij"_mst) | // g=g_x+g_y, h=h_x+h_y, i=i_x+i_y, j=j_x+j_y + (x & y & "k"_mst); // k=k_x*k_y + case Fragment::OR_C: return + (y & "V"_mst).If(x << "Bdu"_mst) | // V=V_y*B_x*u_x*d_x + (x & "o"_mst).If(y << "z"_mst) | // o=o_x*z_y + (x & y & "m"_mst).If(x << "e"_mst && (x | y) << "s"_mst) | // m=m_x*m_y*e_x*(s_x+s_y) + (x & y & "zs"_mst) | // z=z_x*z_y, s=s_x*s_y + "fx"_mst | // f, x + ((x | y) & "ghij"_mst) | // g=g_x+g_y, h=h_x+h_y, i=i_x+i_y, j=j_x+j_y + (x & y & "k"_mst); // k=k_x*k_y + case Fragment::OR_I: return + (x & y & "VBKufs"_mst) | // V=V_x*V_y, B=B_x*B_y, K=K_x*K_y, u=u_x*u_y, f=f_x*f_y, s=s_x*s_y + "o"_mst.If((x & y) << "z"_mst) | // o=z_x*z_y + ((x | y) & "e"_mst).If((x | y) << "f"_mst) | // e=e_x*f_y+f_x*e_y + (x & y & "m"_mst).If((x | y) << "s"_mst) | // m=m_x*m_y*(s_x+s_y) + ((x | y) & "d"_mst) | // d=d_x+d_y + "x"_mst | // x + ((x | y) & "ghij"_mst) | // g=g_x+g_y, h=h_x+h_y, i=i_x+i_y, j=j_x+j_y + (x & y & "k"_mst); // k=k_x*k_y + case Fragment::ANDOR: return + (y & z & "BKV"_mst).If(x << "Bdu"_mst) | // B=B_x*d_x*u_x*B_y*B_z, K=B_x*d_x*u_x*K_y*K_z, V=B_x*d_x*u_x*V_y*V_z + (x & y & z & "z"_mst) | // z=z_x*z_y*z_z + ((x | (y & z)) & "o"_mst).If((x | (y & z)) << "z"_mst) | // o=o_x*z_y*z_z+z_x*o_y*o_z + (y & z & "u"_mst) | // u=u_y*u_z + (z & "f"_mst).If((x << "s"_mst) || (y << "f"_mst)) | // f=(s_x+f_y)*f_z + (z & "d"_mst) | // d=d_z + (x & z & "e"_mst).If(x << "s"_mst || y << "f"_mst) | // e=e_x*e_z*(s_x+f_y) + (x & y & z & "m"_mst).If(x << "e"_mst && (x | y | z) << "s"_mst) | // m=m_x*m_y*m_z*e_x*(s_x+s_y+s_z) + (z & (x | y) & "s"_mst) | // s=s_z*(s_x+s_y) + "x"_mst | // x + ((x | y | z) & "ghij"_mst) | // g=g_x+g_y+g_z, h=h_x+h_y+h_z, i=i_x+i_y+i_z, j=j_x+j_y_j_z + "k"_mst.If(((x & y & z) << "k"_mst) && + !(((x << "g"_mst) && (y << "h"_mst)) || + ((x << "h"_mst) && (y << "g"_mst)) || + ((x << "i"_mst) && (y << "j"_mst)) || + ((x << "j"_mst) && (y << "i"_mst)))); // k=k_x*k_y*k_z* !(g_x*h_y + h_x*g_y + i_x*j_y + j_x*i_y) + case Fragment::MULTI: return "Bnudemsk"_mst; + case Fragment::THRESH: { + bool all_e = true; + bool all_m = true; + uint32_t args = 0; + uint32_t num_s = 0; + Type acc_tl = "k"_mst; + for (size_t i = 0; i < sub_types.size(); ++i) { + Type t = sub_types[i]; + if (!(t << (i ? "Wdu"_mst : "Bdu"_mst))) return ""_mst; // Require Bdu, Wdu, Wdu, ... + if (!(t << "e"_mst)) all_e = false; + if (!(t << "m"_mst)) all_m = false; + if (t << "s"_mst) num_s += 1; + args += (t << "z"_mst) ? 0 : (t << "o"_mst) ? 1 : 2; + acc_tl = ((acc_tl | t) & "ghij"_mst) | + // Thresh contains a combination of timelocks if it has threshold > 1 and + // it contains two different children that have different types of timelocks + // Note how if any of the children don't have "k", the parent also does not have "k" + "k"_mst.If(((acc_tl & t) << "k"_mst) && ((k <= 1) || + ((k > 1) && !(((acc_tl << "g"_mst) && (t << "h"_mst)) || + ((acc_tl << "h"_mst) && (t << "g"_mst)) || + ((acc_tl << "i"_mst) && (t << "j"_mst)) || + ((acc_tl << "j"_mst) && (t << "i"_mst)))))); + } + return "Bdu"_mst | + "z"_mst.If(args == 0) | // z=all z + "o"_mst.If(args == 1) | // o=all z except one o + "e"_mst.If(all_e && num_s == n_subs) | // e=all e and all s + "m"_mst.If(all_e && all_m && num_s >= n_subs - k) | // m=all e, >=(n-k) s + "s"_mst.If(num_s >= n_subs - k + 1) | // s= >=(n-k+1) s + acc_tl; // timelock info + } + } + assert(false); + return ""_mst; +} + +size_t ComputeScriptLen(Fragment nodetype, Type sub0typ, size_t subsize, uint32_t k, size_t n_subs, size_t n_keys) { + switch (nodetype) { + case Fragment::JUST_1: + case Fragment::JUST_0: return 1; + case Fragment::PK_K: return 34; + case Fragment::PK_H: return 3 + 21; + case Fragment::OLDER: + case Fragment::AFTER: return 1 + BuildScript(k).size(); + case Fragment::HASH256: + case Fragment::SHA256: return 4 + 2 + 33; + case Fragment::HASH160: + case Fragment::RIPEMD160: return 4 + 2 + 21; + case Fragment::MULTI: return 3 + (n_keys > 16) + (k > 16) + 34 * n_keys; + case Fragment::AND_V: return subsize; + case Fragment::WRAP_V: return subsize + (sub0typ << "x"_mst); + case Fragment::WRAP_S: + case Fragment::WRAP_C: + case Fragment::WRAP_N: + case Fragment::AND_B: + case Fragment::OR_B: return subsize + 1; + case Fragment::WRAP_A: + case Fragment::OR_C: return subsize + 2; + case Fragment::WRAP_D: + case Fragment::OR_D: + case Fragment::OR_I: + case Fragment::ANDOR: return subsize + 3; + case Fragment::WRAP_J: return subsize + 4; + case Fragment::THRESH: return subsize + n_subs + BuildScript(k).size(); + } + assert(false); + return 0; +} + +bool DecomposeScript(const CScript& script, std::vector<std::pair<opcodetype, std::vector<unsigned char>>>& out) +{ + out.clear(); + CScript::const_iterator it = script.begin(), itend = script.end(); + while (it != itend) { + std::vector<unsigned char> push_data; + opcodetype opcode; + if (!script.GetOp(it, opcode, push_data)) { + out.clear(); + return false; + } else if (opcode >= OP_1 && opcode <= OP_16) { + // Deal with OP_n (GetOp does not turn them into pushes). + push_data.assign(1, CScript::DecodeOP_N(opcode)); + } else if (opcode == OP_CHECKSIGVERIFY) { + // Decompose OP_CHECKSIGVERIFY into OP_CHECKSIG OP_VERIFY + out.emplace_back(OP_CHECKSIG, std::vector<unsigned char>()); + opcode = OP_VERIFY; + } else if (opcode == OP_CHECKMULTISIGVERIFY) { + // Decompose OP_CHECKMULTISIGVERIFY into OP_CHECKMULTISIG OP_VERIFY + out.emplace_back(OP_CHECKMULTISIG, std::vector<unsigned char>()); + opcode = OP_VERIFY; + } else if (opcode == OP_EQUALVERIFY) { + // Decompose OP_EQUALVERIFY into OP_EQUAL OP_VERIFY + out.emplace_back(OP_EQUAL, std::vector<unsigned char>()); + opcode = OP_VERIFY; + } else if (IsPushdataOp(opcode)) { + if (!CheckMinimalPush(push_data, opcode)) return false; + } else if (it != itend && (opcode == OP_CHECKSIG || opcode == OP_CHECKMULTISIG || opcode == OP_EQUAL) && (*it == OP_VERIFY)) { + // Rule out non minimal VERIFY sequences + return false; + } + out.emplace_back(opcode, std::move(push_data)); + } + std::reverse(out.begin(), out.end()); + return true; +} + +bool ParseScriptNumber(const std::pair<opcodetype, std::vector<unsigned char>>& in, int64_t& k) { + if (in.first == OP_0) { + k = 0; + return true; + } + if (!in.second.empty()) { + if (IsPushdataOp(in.first) && !CheckMinimalPush(in.second, in.first)) return false; + try { + k = CScriptNum(in.second, true).GetInt64(); + return true; + } catch(const scriptnum_error&) {} + } + return false; +} + +int FindNextChar(Span<const char> sp, const char m) +{ + for (int i = 0; i < (int)sp.size(); ++i) { + if (sp[i] == m) return i; + // We only search within the current parentheses + if (sp[i] == ')') break; + } + return -1; +} + +} // namespace internal +} // namespace miniscript |