// aud.hoa · AudioCodecs · APACHOADecoder::Initialize · CVE-2026-112546
// 原语: OOB 读 · 系统进程 · tier 2
// Primitive: OOB read · system process · tier 2
//
// [zh] HOA 空间音频系数越界读
// mNumHOAcoeffs 由文件内的 hoa::CodecConfig 反序列化取得。既有检查仅拦下大于 122 的值，而 37 至 121 之间的取值会索引一个长度为 37 的数组。27.2
// 将比较阈值改为 0x25。
//
// [en] HOA spatial audio coefficient out-of-bounds read
// mNumHOAcoeffs is deserialised from the file's hoa::CodecConfig. The existing check only rejects
// values above 122, while anything from 37 to 121 indexes an array of length 37. iOS 27.2 changes
// the comparison threshold to 0x25.
// ── 判别 / oracle ──
// 系数上限来自 kMaxNumSCs_DynSelSCs4EachSB。这条要真正打进去需要 MPEG-H / 沉浸式音频文件，应用侧只能探到解码器是否可达。

import Foundation

// ── byte helpers — verbatim from Cinder27 Sources/Kit.swift ──
enum B {
    static func be16(_ v: UInt16) -> [UInt8] { [UInt8(v >> 8 & 0xff), UInt8(v & 0xff)] }
    static func le16(_ v: UInt16) -> [UInt8] { [UInt8(v & 0xff), UInt8(v >> 8 & 0xff)] }
    static func be32(_ v: UInt32) -> [UInt8] {
        [UInt8(v >> 24 & 0xff), UInt8(v >> 16 & 0xff), UInt8(v >> 8 & 0xff), UInt8(v & 0xff)]
    }
    static func le32(_ v: UInt32) -> [UInt8] {
        [UInt8(v & 0xff), UInt8(v >> 8 & 0xff), UInt8(v >> 16 & 0xff), UInt8(v >> 24 & 0xff)]
    }
    static func be64(_ v: UInt64) -> [UInt8] {
        (0..<8).map { UInt8((v >> (56 - UInt64($0) * 8)) & 0xff) }
    }
    static func le64(_ v: UInt64) -> [UInt8] {
        (0..<8).map { UInt8((v >> (UInt64($0) * 8)) & 0xff) }
    }
    static func both16(_ v: UInt16) -> [UInt8] { le16(v) + be16(v) }
    static func both32(_ v: UInt32) -> [UInt8] { le32(v) + be32(v) }
    static func ascii(_ s: String) -> [UInt8] { Array(s.utf8) }
}