// sb.stash · SpringBoard · SBHomeScreenService · CVE-2026-112646
// 原语: OOB 写 · 系统进程 · tier 3
// Primitive: OOB write · system process · tier 3
//
// [zh] SpringBoard 布局名 stash 校验
// 27.2 新增 +[SBHomeScreenService _validationErrorForStashedLayoutName:]：拒绝空串、限制长度 ≤ 64、施加字符集白名单，作用于
// stash/restore 的 XPC 接口。27.0 的该接口不含此层校验。
//
// [en] SpringBoard stashed layout name validation
// iOS 27.2 adds +[SBHomeScreenService _validationErrorForStashedLayoutName:]: reject empty, cap length
// at 64, apply a character-set allowlist, on the stash/restore XPC interface. The 27.0 interface
// has no such layer.
// ── 判别 / oracle ──
// 应用侧只能看 SpringBoard 服务是否可达、类是否在进程里。真正的入口是 XPC，需要越过沙盒。

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) }
}