Load from Memory

JadeView 2.0 supports loading JAPK packages directly from memory, without a local file system. This is suitable for scenarios where JAPK data is embedded in an executable or used directly after being downloaded from the network.

This page describes the memory-loading APIs. To load from a local file, see Load from Local. To build an obfuscated JAPK package, use the JadePack desktop client.

Overview

JadeView_load_from_bytes loads a JAPK package from memory, detecting the package format via the magic number:

Only JAPK v2 signed packages are accepted, decrypted and loaded after verification against the JadeTweak platform root public key embedded in JadeView
The verification public key is compiled into the DLL; hosts do not need to (and cannot) inject one at runtime

💡 Tip: Both signed and obfuscated packages are built by JadePack. Memory loading only accepts signed packages; load obfuscated packages from a local file instead.

Format	Magic number	Description	Build tool
JAPK v2 signed package	`JAPKV002`	Ed25519 signature + AES-256-GCM encryption	JadePack
Obfuscated package v2	`JPKBIN02`	SHA256 dynamic key derivation + 3-layer reversible transform	JadePack

Key security constraint: Memory loading only accepts JAPK v2 signed packages; a failed signature verification will never fall back to the obfuscated-package logic.

Core API

JadeView_load_from_bytes

Loads a JAPK package from memory.

int JadeView_load_from_bytes(const uint8_t* japk_data, size_t data_size);

Parameters:

japk_data uint8_t* - Pointer to the JAPK file data
data_size size_t - Data size (in bytes)

Return value:

0 - Loaded successfully
Negative number - Error code; see the error code table below

Call order:

JadeView_init — Initialize the runtime
JadeView_load_from_bytes — Load the JAPK data

JadeView_is_loaded

Checks whether a JAPK package has been loaded successfully.

int JadeView_is_loaded(void);

Return value:

1 - Loaded
0 - Not loaded

JadeView_get_app_signature

Returns the app_signature set during JadeView_init (regardless of whether a package is loaded or its package type).

char* JadeView_get_app_signature(void);

Return value:

Non-NULL - The application identifier string; the caller must free it with jade_text_free

JadeView_get_signature_info

Returns the signature information JSON. Has a value only after a signed package has been loaded successfully.

char* JadeView_get_signature_info(void);

Return value:

Non-NULL - The signature information JSON string; the caller must free it with jade_text_free

JadeView_unload

Clears the loaded state and releases the in-memory JAPK data.

int JadeView_unload(void);

Error Codes

Value	Constant	Description
`0`	`JADEVIEW_JAPK_OK`	Success
`-1`	`JADEVIEW_JAPK_ERROR_INVALID_PARAM`	Invalid parameter (null pointer / size 0)
`-2`	`JADEVIEW_JAPK_ERROR_NOT_INITIALIZED`	`JadeView_init` was not called
`-3`	`JADEVIEW_JAPK_ERROR_LOAD_FAILED`	Load failed
`-4`	`JADEVIEW_JAPK_ERROR_INVALID_FORMAT`	Invalid / unsupported format
`-5`	`JADEVIEW_JAPK_ERROR_INVALID_SIGNATURE`	Signature verification failed
`-6`	`JADEVIEW_JAPK_ERROR_APP_MISMATCH`	app_signature/app_name mismatch
`-7`	`JADEVIEW_JAPK_ERROR_DECRYPT_FAILED`	Decryption / deobfuscation failed
`-8`	`JADEVIEW_JAPK_ERROR_UNSIGNED_NOT_ALLOWED`	Signed package is missing a signature
`-9`	`JADEVIEW_JAPK_ERROR_MISSING_PUBLIC_KEY`	Public key not set
`-10`	`JADEVIEW_JAPK_ERROR_INVALID_PUBLIC_KEY`	Invalid public key format
`-11`	`JADEVIEW_JAPK_ERROR_POLICY_DENIED`	Denied by security policy
`-12`	`JADEVIEW_JAPK_ERROR_NOT_LOADED`	Not loaded

Events

The loading process is notified asynchronously via callbacks registered with jade_on:

japk-load-success

Triggered when loading succeeds; the callback receives JSON data:

JSON

{
  "app_signature": "com.example.app",
  "app_name": "MyApp",
  "asar_size": 1048576,
  "type": "signed"
}

Field	Signed package	Obfuscated package
`app_signature`	✓	✗
`app_name`	✓	✗
`asar_size`	✓	✓
`type`	`"signed"`	`"scrambled"`

japk-load-failed

Triggered when loading fails; the callback receives a plain-text error message, such as "Signature verification failed".

Usage Examples

C

#include "JadeView.h"

void load_from_memory_example() {
    // 1. Initialize
    JadeView_init(1, NULL, NULL, "MyApp", "com.example.app", 0);

    // 2. Read the JAPK file into memory
    FILE* f = fopen("app.japk", "rb");
    fseek(f, 0, SEEK_END);
    size_t size = ftell(f);
    fseek(f, 0, SEEK_SET);
    uint8_t* data = malloc(size);
    fread(data, 1, size, f);
    fclose(f);

    // 3. Load from memory (JAPK v2 signed package)
    int rc = JadeView_load_from_bytes(data, size);
    if (rc != 0) {
        printf("Load failed: %d\n", rc);
        free(data);
        return;
    }

    // 4. Get the protocol URL (pass an empty string for memory loading)
    char url_buffer[256];
    set_protocol_service_path("", url_buffer, sizeof(url_buffer), 0);  // 4th param hot_reload; pass 0 for memory loading
    // url_buffer content looks like: JADE://{app_signature}/ (app_signature is the 5th JadeView_init arg, lowercased)

    // 5. Create a window using that URL
    WebViewWindowOptions options = {
        .title = "JAPK Memory Load",
        .width = 800,
        .height = 600,
        .frame_style = "normal"
    };
    create_webview_window(url_buffer, 0, &options, NULL);

    free(data);
}

Python (ctypes)

Python

import ctypes
from ctypes import c_char_p, c_int, c_uint8, c_size_t, POINTER

dll = ctypes.WinDLL("JadeView.dll")

dll.JadeView_init.argtypes = [c_int, c_char_p, c_char_p, c_char_p, c_char_p, c_int]
dll.JadeView_init.restype = c_int

dll.JadeView_load_from_bytes.argtypes = [POINTER(c_uint8), c_size_t]
dll.JadeView_load_from_bytes.restype = c_int

dll.JadeView_is_loaded.argtypes = []
dll.JadeView_is_loaded.restype = c_int

# 1. Initialize
dll.JadeView_init(1, None, b"./data", b"MyApp", b"com.example.app", 0)

# 2. Read the JAPK into memory
with open("app.japk", "rb") as f:
    japk_data = f.read()

# 3. Load from memory (JAPK v2 signed package)
data_ptr = (c_uint8 * len(japk_data)).from_buffer_copy(japk_data)
rc = dll.JadeView_load_from_bytes(data_ptr, len(japk_data))
if rc != 0:
    raise RuntimeError(f"JadeView_load_from_bytes failed: {rc}")

# 4. Get the protocol URL (pass an empty string for memory loading)
dll.set_protocol_service_path.argtypes = [c_char_p, c_char_p, c_size_t, c_int]
dll.set_protocol_service_path.restype = c_int

url_buffer = ctypes.create_string_buffer(256)
dll.set_protocol_service_path(b"", url_buffer, 256, 0)  # 4th param hot_reload; pass 0 for memory loading
print(f"Protocol URL: {url_buffer.value.decode()}")

# 5. Create a window using that URL
loaded = dll.JadeView_is_loaded()
print(f"JAPK loaded: {loaded}")

Full Call Sequence

Markdown

Caller                          JadeView DLL
  │                                 │
  ├─ JadeView_init ────────────────►│ Initialize
  │                                 │
  ├─ jade_on("japk-load-success")──►│ Register success callback
  ├─ jade_on("japk-load-failed") ──►│ Register failure callback
  │                                 │
  ├─ JadeView_load_from_bytes ─────►│ Magic detection → signature verification/decryption → ASAR
  │                                 │
  │  ◄── japk-load-success ────────┤ Asynchronous event
  │                                 │
  ├─ set_protocol_service_path("")─►│ Get protocol URL
  │  ◄── url_buffer ───────────────┤ JADE://{app_signature}/
  │                                 │
  ├─ create_webview_window(url) ───►│ Create window
  │                                 │
  ├─ run_message_loop ─────────────►│ Enter the event loop