39 lines
1.3 KiB
Swift
39 lines
1.3 KiB
Swift
// SPDX-FileCopyrightText: 2026 Kaede Akino
|
|
// SPDX-License-Identifier: GPL-3.0-only
|
|
|
|
import CryptoKit
|
|
import Foundation
|
|
|
|
/// RFC 4251 fields shared by public keys, signatures, and agent replies.
|
|
nonisolated enum SSHWireEncoding {
|
|
static func uint32(_ value: UInt32) -> Data {
|
|
var value = value.bigEndian
|
|
return withUnsafeBytes(of: &value) { Data($0) }
|
|
}
|
|
|
|
static func field(_ data: Data) -> Data { uint32(UInt32(data.count)) + data }
|
|
|
|
/// Encodes a nonnegative integer, including its SSH field length.
|
|
static func mpint<S: DataProtocol>(_ bytes: S) -> Data {
|
|
var value = Data(Data(bytes).drop(while: { $0 == 0 }))
|
|
if value.first.map({ $0 & 0x80 != 0 }) == true { value.insert(0, at: value.startIndex) }
|
|
return field(value)
|
|
}
|
|
|
|
static func fingerprint(of blob: Data) -> String {
|
|
let digest = Data(SHA256.hash(data: blob)).base64EncodedString()
|
|
.replacingOccurrences(of: "=", with: "")
|
|
return "SHA256:\(digest)"
|
|
}
|
|
|
|
/// The value of one ASCII hexadecimal digit, or nil for any other byte.
|
|
static func hexDigit(_ byte: UInt8) -> UInt8? {
|
|
switch byte {
|
|
case 0x30...0x39: byte - 0x30
|
|
case 0x41...0x46: byte - 0x41 + 10
|
|
case 0x61...0x66: byte - 0x61 + 10
|
|
default: nil
|
|
}
|
|
}
|
|
}
|