Address & script parsing refactor

frontend/src/app/shared/script.utils.ts

@@ -145,8 +145,116 @@ for (let i = 187; i <= 255; i++) {
 
 export { opcodes };
 
+export type ScriptType = 'scriptpubkey'
+  | 'scriptsig'
+  | 'inner_witnessscript'
+  | 'inner_redeemscript'
+
+export interface ScriptTemplate {
+  type: string;
+  label: string;
+}
+
+export const ScriptTemplates: { [type: string]: (...args: any) => ScriptTemplate } = {
+  liquid_peg_out: () => ({ type: 'liquid_peg_out', label: 'Liquid Peg Out' }),
+  liquid_peg_out_emergency: () => ({ type: 'liquid_peg_out_emergency', label: 'Emergency Liquid Peg Out' }),
+  ln_force_close: () => ({ type: 'ln_force_close', label: 'Lightning Force Close' }),
+  ln_force_close_revoked: () => ({ type: 'ln_force_close_revoked', label: 'Revoked Lightning Force Close' }),
+  ln_htlc: () => ({ type: 'ln_htlc', label: 'Lightning HTLC' }),
+  ln_htlc_revoked: () => ({ type: 'ln_htlc_revoked', label: 'Revoked Lightning HTLC' }),
+  ln_htlc_expired: () => ({ type: 'ln_htlc_expired', label: 'Expired Lightning HTLC' }),
+  ln_anchor: () => ({ type: 'ln_anchor', label: 'Lightning Anchor' }),
+  ln_anchor_swept: () => ({ type: 'ln_anchor_swept', label: 'Swept Lightning Anchor' }),
+  multisig: (m: number, n: number) => ({ type: 'multisig', m, n, label: $localize`:@@address-label.multisig:Multisig ${m}:multisigM: of ${n}:multisigN:` }),
+};
+
+export class ScriptInfo {
+  type: ScriptType;
+  scriptPath?: string;
+  hex?: string;
+  asm?: string;
+  template: ScriptTemplate;
+
+  constructor(type: ScriptType, hex?: string, asm?: string, witness?: string[], scriptPath?: string) {
+    this.type = type;
+    this.hex = hex;
+    this.asm = asm;
+    if (scriptPath) {
+      this.scriptPath = scriptPath;
+    }
+    if (this.asm) {
+      this.template = detectScriptTemplate(this.type, this.asm, witness);
+    }
+  }
+
+  public clone(): ScriptInfo {
+    return { ...this };
+  }
+
+  get key(): string {
+    return this.type + (this.scriptPath || '');
+  }
+}
+
+/** parses an inner_witnessscript + witness stack, and detects named script types */
+export function detectScriptTemplate(type: ScriptType, script_asm: string, witness?: string[]): ScriptTemplate | undefined {
+  if (type === 'inner_witnessscript' && witness?.length) {
+    if (script_asm.indexOf('OP_DEPTH OP_PUSHNUM_12 OP_EQUAL OP_IF OP_PUSHNUM_11') === 0 || script_asm.indexOf('OP_PUSHNUM_15 OP_CHECKMULTISIG OP_IFDUP OP_NOTIF OP_PUSHBYTES_2') === 1259) {
+      if (witness.length > 11) {
+        return ScriptTemplates.liquid_peg_out();
+      } else {
+        return ScriptTemplates.liquid_peg_out_emergency();
+      }
+    }
+
+    const topElement = witness[witness.length - 2];
+    if (/^OP_IF OP_PUSHBYTES_33 \w{66} OP_ELSE OP_PUSH(NUM_\d+|BYTES_(1 \w{2}|2 \w{4})) OP_CSV OP_DROP OP_PUSHBYTES_33 \w{66} OP_ENDIF OP_CHECKSIG$/.test(script_asm)) {
+      // https://github.com/lightning/bolts/blob/master/03-transactions.md#commitment-transaction-outputs
+      if (topElement === '01') {
+        // top element is '01' to get in the revocation path
+        return ScriptTemplates.ln_force_close_revoked();
+      } else {
+        // top element is '', this is a delayed to_local output
+        return ScriptTemplates.ln_force_close();
+      }
+    } else if (
+      /^OP_DUP OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUAL OP_IF OP_CHECKSIG OP_ELSE OP_PUSHBYTES_33 \w{66} OP_SWAP OP_SIZE OP_PUSHBYTES_1 20 OP_EQUAL OP_NOTIF OP_DROP OP_PUSHNUM_2 OP_SWAP OP_PUSHBYTES_33 \w{66} OP_PUSHNUM_2 OP_CHECKMULTISIG OP_ELSE OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUALVERIFY OP_CHECKSIG OP_ENDIF (OP_PUSHNUM_1 OP_CSV OP_DROP |)OP_ENDIF$/.test(script_asm) ||
+      /^OP_DUP OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUAL OP_IF OP_CHECKSIG OP_ELSE OP_PUSHBYTES_33 \w{66} OP_SWAP OP_SIZE OP_PUSHBYTES_1 20 OP_EQUAL OP_IF OP_HASH160 OP_PUSHBYTES_20 \w{40} OP_EQUALVERIFY OP_PUSHNUM_2 OP_SWAP OP_PUSHBYTES_33 \w{66} OP_PUSHNUM_2 OP_CHECKMULTISIG OP_ELSE OP_DROP OP_PUSHBYTES_3 \w{6} OP_CLTV OP_DROP OP_CHECKSIG OP_ENDIF (OP_PUSHNUM_1 OP_CSV OP_DROP |)OP_ENDIF$/.test(script_asm)
+    ) {
+      // https://github.com/lightning/bolts/blob/master/03-transactions.md#offered-htlc-outputs
+      // https://github.com/lightning/bolts/blob/master/03-transactions.md#received-htlc-outputs
+      if (topElement.length === 66) {
+        // top element is a public key
+        return ScriptTemplates.ln_htlc_revoked();
+      } else if (topElement) {
+        // top element is a preimage
+        return ScriptTemplates.ln_htlc();
+      } else {
+        // top element is '' to get in the expiry of the script
+        return ScriptTemplates.ln_htlc_expired();
+      }
+    } else if (/^OP_PUSHBYTES_33 \w{66} OP_CHECKSIG OP_IFDUP OP_NOTIF OP_PUSHNUM_16 OP_CSV OP_ENDIF$/.test(script_asm)) {
+      // https://github.com/lightning/bolts/blob/master/03-transactions.md#to_local_anchor-and-to_remote_anchor-output-option_anchors
+      if (topElement) {
+        // top element is a signature
+        return ScriptTemplates.ln_anchor();
+      } else {
+        // top element is '', it has been swept after 16 blocks
+        return ScriptTemplates.ln_anchor_swept();
+      }
+    }
+  }
+
+  const multisig = parseMultisigScript(script_asm);
+  if (multisig) {
+    return ScriptTemplates.multisig(multisig.m, multisig.n);
+  }
+
+  return;
+}
+
 /** extracts m and n from a multisig script (asm), returns nothing if it is not a multisig script */
-export function parseMultisigScript(script: string): void | { m: number, n: number } {
+export function parseMultisigScript(script: string): undefined | { m: number, n: number } {
   if (!script) {
     return;
   }