Initial commit

Co-Authored-By: Claude Opus 4.8 (1M context) <noreply@anthropic.com>

node_modules/postject/dist/cli.js

@@ -0,0 +1,75 @@
+#!/usr/bin/env node
+
+const program = require("commander");
+const { constants, promises: fs } = require("fs");
+const path = require("path");
+const { inject } = require("./api.js");
+
+const logger = {
+  info: (message) => console.log("\x1b[36m%s\x1b[0m", message),
+  success: (message) => console.log("\x1b[32m%s\x1b[0m", message),
+  error: (message) => console.log("\x1b[31mError: %s\x1b[0m", message),
+};
+
+async function main(filename, resourceName, resource, options) {
+  if (options.outputApiHeader) {
+    // Handles --output-api-header.
+    console.log(
+      await fs.readFile(path.join(__dirname, "postject-api.h"), "utf-8")
+    );
+    process.exit();
+  }
+
+  let resourceData;
+
+  try {
+    await fs.access(resource, constants.R_OK);
+    resourceData = await fs.readFile(resource);
+  } catch {
+    logger.error("Can't read resource file");
+    process.exit(1);
+  }
+
+  try {
+    logger.info(
+      "Start injection of " + resourceName + " in " + filename + "..."
+    );
+    await inject(filename, resourceName, resourceData, {
+      machoSegmentName: options.machoSegmentName,
+      overwrite: options.overwrite,
+      sentinelFuse: options.sentinelFuse,
+    });
+    logger.success("💉 Injection done!");
+  } catch (err) {
+    logger.error(err.message);
+    process.exit(1);
+  }
+}
+
+if (require.main === module) {
+  program
+    .name("postject")
+    .description(
+      "Inject arbitrary read-only resources into an executable for use at runtime"
+    )
+    .argument("<filename>", "The executable to inject into")
+    .argument(
+      "<resource_name>",
+      "The resource name to use (section name on Mach-O and ELF, resource name for PE)"
+    )
+    .argument("<resource>", "The resource to inject")
+    .option(
+      "--macho-segment-name <segment_name>",
+      "Name for the Mach-O segment",
+      "__POSTJECT"
+    )
+    .option(
+      "--sentinel-fuse <sentinel_fuse>",
+      "Sentinel fuse for resource presence detection",
+      "POSTJECT_SENTINEL_fce680ab2cc467b6e072b8b5df1996b2"
+    )
+    .option("--output-api-header", "Output the API header to stdout")
+    .option("--overwrite", "Overwrite the resource if it already exists")
+    .action(main)
+    .parse(process.argv);
+}

node_modules/postject/dist/postject-api.h

@@ -0,0 +1,209 @@
+#ifndef POSTJECT_API_H_
+#define POSTJECT_API_H_
+
+#include <stdbool.h>
+#include <stddef.h>
+#include <stdlib.h>
+#include <string.h>
+
+#if defined(__APPLE__) && defined(__MACH__)
+#include <mach-o/dyld.h>
+#include <mach-o/getsect.h>
+#elif defined(__linux__)
+#include <elf.h>
+#include <link.h>
+#include <sys/param.h>
+#elif defined(_WIN32)
+#include <windows.h>
+#endif
+
+#ifndef POSTJECT_SENTINEL_FUSE
+#define POSTJECT_SENTINEL_FUSE \
+  "POSTJECT_SENTINEL_fce680ab2cc467b6e072b8b5df1996b2"
+#endif
+
+struct postject_options {
+  const char* elf_section_name;
+  const char* macho_framework_name;
+  const char* macho_section_name;
+  const char* macho_segment_name;
+  const char* pe_resource_name;
+};
+
+inline void postject_options_init(struct postject_options* options) {
+  options->elf_section_name = NULL;
+  options->macho_framework_name = NULL;
+  options->macho_section_name = NULL;
+  options->macho_segment_name = NULL;
+  options->pe_resource_name = NULL;
+}
+
+static inline bool postject_has_resource() {
+  static const volatile char* sentinel = POSTJECT_SENTINEL_FUSE ":0";
+  return sentinel[sizeof(POSTJECT_SENTINEL_FUSE)] == '1';
+}
+
+#if defined(__linux__)
+static int postject__dl_iterate_phdr_callback(struct dl_phdr_info* info,
+                                              size_t size,
+                                              void* data) {
+  // Snag the dl_phdr_info struct for the main program, then stop iterating
+  *((struct dl_phdr_info*)data) = *info;
+  return 1;
+}
+#endif
+
+static const void* postject_find_resource(
+    const char* name,
+    size_t* size,
+    const struct postject_options* options) {
+  // Always zero out the size pointer to start
+  if (size != NULL) {
+    *size = 0;
+  }
+
+#if defined(__APPLE__) && defined(__MACH__)
+  char* section_name = NULL;
+  const char* segment_name = "__POSTJECT";
+
+  if (options != NULL && options->macho_segment_name != NULL) {
+    segment_name = options->macho_segment_name;
+  }
+
+  if (options != NULL && options->macho_section_name != NULL) {
+    name = options->macho_section_name;
+  } else if (strncmp(name, "__", 2) != 0) {
+    // Automatically prepend __ to match naming convention
+    section_name = (char*)malloc(strlen(name) + 3);
+    if (section_name == NULL) {
+      return NULL;
+    }
+    strcpy(section_name, "__");
+    strcat(section_name, name);
+  }
+
+  unsigned long section_size;
+  char* ptr = NULL;
+  if (options != NULL && options->macho_framework_name != NULL) {
+#ifdef __clang__
+#pragma clang diagnostic push
+#pragma clang diagnostic ignored "-Wdeprecated-declarations"
+#endif
+    ptr = getsectdatafromFramework(options->macho_framework_name, segment_name,
+                                   section_name != NULL ? section_name : name,
+                                   &section_size);
+  } else {
+    ptr = getsectdata(segment_name, section_name != NULL ? section_name : name,
+                      &section_size);
+#ifdef __clang__
+#pragma clang diagnostic pop
+#endif
+
+    if (ptr != NULL) {
+      // Add the "virtual memory address slide" amount to ensure a valid pointer
+      // in cases where the virtual memory address have been adjusted by the OS.
+      //
+      // NOTE - `getsectdataFromFramework` already handles this adjustment for
+      //        us, which is why we only do it for `getsectdata`, see:
+      //        https://web.archive.org/web/20220613234007/https://opensource.apple.com/source/cctools/cctools-590/libmacho/getsecbyname.c.auto.html
+      ptr += _dyld_get_image_vmaddr_slide(0);
+    }
+  }
+
+  free(section_name);
+
+  if (size != NULL) {
+    *size = (size_t)section_size;
+  }
+
+  return ptr;
+#elif defined(__linux__)
+
+  if (options != NULL && options->elf_section_name != NULL) {
+    name = options->elf_section_name;
+  }
+
+  struct dl_phdr_info main_program_info;
+  dl_iterate_phdr(postject__dl_iterate_phdr_callback, &main_program_info);
+
+  uintptr_t p = (uintptr_t)main_program_info.dlpi_phdr;
+  size_t n = main_program_info.dlpi_phnum;
+  uintptr_t base_addr = main_program_info.dlpi_addr;
+
+  // iterate program header
+  for (; n > 0; n--, p += sizeof(ElfW(Phdr))) {
+    ElfW(Phdr)* phdr = (ElfW(Phdr)*)p;
+
+    // skip everything but notes
+    if (phdr->p_type != PT_NOTE) {
+      continue;
+    }
+
+    // note segment starts at base address + segment virtual address
+    uintptr_t pos = (base_addr + phdr->p_vaddr);
+    uintptr_t end = (pos + phdr->p_memsz);
+
+    // iterate through segment until we reach the end
+    while (pos < end) {
+      if (pos + sizeof(ElfW(Nhdr)) > end) {
+        break;  // invalid
+      }
+
+      ElfW(Nhdr)* note = (ElfW(Nhdr)*)(uintptr_t)pos;
+      if (note->n_namesz != 0 && note->n_descsz != 0 &&
+          strncmp((char*)(pos + sizeof(ElfW(Nhdr))), (char*)name,
+                  sizeof(name)) == 0) {
+        *size = note->n_descsz;
+        // advance past note header and aligned name
+        // to get to description data
+        return (void*)((uintptr_t)note + sizeof(ElfW(Nhdr)) +
+                       roundup(note->n_namesz, 4));
+      }
+
+      pos += (sizeof(ElfW(Nhdr)) + roundup(note->n_namesz, 4) +
+              roundup(note->n_descsz, 4));
+    }
+  }
+  return NULL;
+
+#elif defined(_WIN32)
+  void* ptr = NULL;
+  char* resource_name = NULL;
+
+  if (options != NULL && options->pe_resource_name != NULL) {
+    name = options->pe_resource_name;
+  } else {
+    // Automatically uppercase the resource name or it won't be found
+    resource_name = (char*)malloc(strlen(name) + 1);
+    if (resource_name == NULL) {
+      return NULL;
+    }
+    strcpy_s(resource_name, strlen(name) + 1, name);
+    CharUpperA(resource_name);  // Uppercases inplace
+  }
+
+  HRSRC resource_handle =
+      FindResourceA(NULL, resource_name != NULL ? resource_name : name,
+                    MAKEINTRESOURCEA(10) /* RT_RCDATA */);
+
+  if (resource_handle) {
+    HGLOBAL global_resource_handle = LoadResource(NULL, resource_handle);
+
+    if (global_resource_handle) {
+      if (size != NULL) {
+        *size = SizeofResource(NULL, resource_handle);
+      }
+
+      ptr = LockResource(global_resource_handle);
+    }
+  }
+
+  free(resource_name);
+
+  return ptr;
+#else
+  return NULL;
+#endif
+}
+
+#endif  // POSTJECT_API_H_