fix(il2cpp): consume resolved ELF program declarations

Retain relevant program facts in the shared native directory and consume them for mappings and relocations. Remove redundant table coordinates and presence flags. This preserves extended program counts so PT_DYNAMIC beyond the raw sentinel remains visible, while load and relocation admission keep their distinct policies.

src/il2cpp/ElfRelocations.ts

@@ -2,6 +2,8 @@ import {
   BinaryMappingFailure,
   mappedFileOffset,
   isZeroFilledSpan,
+  type BinaryContainer,
+  type ElfDynamicSegment,
   type FileMapping,
   type ZeroFillMapping,
 } from "../native/metadata/BinaryContainer.js";
@@ -78,31 +80,28 @@ const RELOCATION_KINDS = new Map([
   ],
 ]);
 
-function* dynamicTags(image: Buffer): Generator<void, Map<bigint, bigint>> {
-  if (image.length < 64) throw malformed("ELF header is truncated");
-  const offset = Number(image.readBigUInt64LE(32)),
-    width = image.readUInt16LE(54),
-    count = image.readUInt16LE(56);
-  if (width < 56 || offset + count * width > image.length)
-    throw malformed("ELF program headers extend beyond the file");
-  let dynamic: { offset: number; size: number } | undefined;
-  for (let index = 0; index < count; index++) {
-    if (index % 256 === 0) yield;
-    const at = offset + index * width;
-    if (image.readUInt32LE(at) !== 2) continue;
-    if (dynamic !== undefined) throw malformed("multiple PT_DYNAMIC segments");
-    dynamic = {
-      offset: Number(image.readBigUInt64LE(at + 8)),
-      size: Number(image.readBigUInt64LE(at + 32)),
-    };
-  }
-  if (dynamic === undefined)
+function* dynamicTags(
+  image: Buffer,
+  declarations: readonly ElfDynamicSegment[],
+): Generator<void, Map<bigint, bigint>> {
+  yield;
+  if (declarations.length > 1) throw malformed("multiple PT_DYNAMIC segments");
+  const declaration = declarations[0];
+  if (declaration === undefined)
     throw new Il2cppBinaryFormatFailure(
       "unsupported-container",
       "ELF image has no PT_DYNAMIC segment",
     );
-  if (dynamic.size % 16 !== 0 || dynamic.offset + dynamic.size > image.length)
+  if (
+    declaration.size % 16n !== 0n ||
+    declaration.offset > BigInt(image.length) ||
+    declaration.size > BigInt(image.length) - declaration.offset
+  )
     throw malformed("PT_DYNAMIC is truncated or outside the file");
+  const dynamic = {
+    offset: Number(declaration.offset),
+    size: Number(declaration.size),
+  };
   const tags = new Map<bigint, bigint>();
   const unique = new Set([
     DT_RELA,
@@ -203,17 +202,17 @@ function* applyRelaTable(
 /** Materialize relative pointers in a private copy, preserving unknown and .bss facts. */
 export function* applyElfRelativeRelocationsSteps(
   image: Buffer,
+  elf: Extract<BinaryContainer, { format: "elf" }>["elf"],
   mappings: readonly FileMapping[],
   zeroFills: readonly ZeroFillMapping[],
 ): Generator<void, RelocatedImage> {
-  if (image.length < 64) throw malformed("ELF header is truncated");
-  const kinds = RELOCATION_KINDS.get(image.readUInt16LE(18));
+  const kinds = RELOCATION_KINDS.get(elf.machine);
   if (kinds === undefined)
     throw new Il2cppBinaryFormatFailure(
       "unsupported-container",
       "ELF relocations require AArch64 or x86-64",
     );
-  const tags = yield* dynamicTags(image);
+  const tags = yield* dynamicTags(image, elf.dynamicSegments);
   if (tags.has(0x6000000fn) || tags.has(0x60000011n) || tags.has(17n))
     throw unsupported(
       "Android packed (APS2) or REL relocations are not decoded",

src/il2cpp/Il2cppBinaryImage.ts

@@ -128,6 +128,7 @@ export function* openImageSteps(
     if (container.format === "elf")
       relocated = yield* applyElfRelativeRelocationsSteps(
         image,
+        container.elf,
         container.mappings,
         container.zero_fills,
       );