ArcaneNibble

Notes on compiling Python + Rust (PyO3) for wasm32-wasip1

Critical metadata

• Date written: 2024-10-30
• Python version: 3.12.7
• Rust version: 1.82.0
• PyO3 version: 0.22.5
• zlib version: 1.3.1

ArcaneNibble

JLCPCB Color Silkscreen Crypto

JLCPCB color silkscreen files are encrypted using AES-128-GCM and RSA-2048 with OAEP padding with SHA-256 as the hash function. Unfortunately, this means that, although it is possible for tools other than EasyEDA to create files, only JLCPCB can decrypt the resulting files.

File structure

The structure of an encrypted file is as follows:

1. 256 bytes RSA-encrypted AES key
2. 256 bytes RSA-encrypted GCM nonce

ArcaneNibble

WCH QingKe RISC-V XW extension opcode encoding

This has been reverse engineered from the toolchain only and has not been tested on hardware.

The c.lbu, c.lhu, c.sb, and c.sh opcodes replace some standard opcodes (that the QingKe cores do not implement, as the replaced opcodes require the D extension), and they also appear to be compatible with "Huawei" extensions mentioned here.

The c.lbusp, c.lhusp, c.sbsp, and c.shsp opcodes exist in a "reserved" opcode block.

001 uimm[0] uimm[4:3] rs1` uimm[2:1] rd`  00			c.lbu		(replacing c.fld)

ArcaneNibble

#include <stdint.h>
#include <string.h>

#include "CH579SFR.h"

void write_str(const char *s) {
	for (uint32_t i = 0; i < strlen(s); i++) {
		while (!(R8_UART1_LSR & RB_LSR_TX_FIFO_EMP)) {}
		R8_UART1_THR = s[i];
	}

ArcaneNibble

GATT

service 0xFFF0 characteristic 0xFFF2 --> commands service 0xFFF0 characteristic 0xFFF1 --> responses

packet format (both commands and responses)

0xB4 0x4B len type <payload> csum len -> number of bytes in payload csum -> add all of the previous bytes in the packet and truncate to 1 byte

fragmented bulk data (within payloads)

ArcaneNibble

import sys


def parse_cnf(infn):
    with open(infn, 'r') as f:
        inp = f.readlines()

    while inp:
        l = inp[0]
        inp = inp[1:]

ArcaneNibble

import sys


def parse_cnf(infn):
    with open(infn, 'r') as f:
        inp = f.readlines()

    # print(inp)
    while inp:
        l = inp[0]

ArcaneNibble

import struct
import time
import usb

dev = usb.core.find(idVendor=0x32f8, idProduct=0x424c)
# print(dev)

dev.set_configuration()

serno = usb.util.get_string(dev, dev.iSerialNumber)

ArcaneNibble

OUTDATED PLEASE GO TO https://github.com/rqou/linux/tree/atc-m1max






if instance == 0
	AUSPLL_CORE_AUSPLL_CFG_DCO_EFUSE_SPARE.RODCO_ENCAP_EFUSE		= efuse 0xa10 >> 25
	AUSPLL_CORE_AUSPLL_CFG_DCO_EFUSE_SPARE.RODCO_BIASADJ_EFUSE		= efuse 0xa10 >> 22

ArcaneNibble

OUTDATED PLEASE GO TO https://github.com/rqou/m1n1/tree/jpeg