我尝试使用Swift使用Secure Transport和BSD套接字。看起来它应该很简单，但我无法使用它并且关于这个主题的文档很少。
我把我的问题归结为一个简单的＆＃34; Socket＆＃34;在我所知的范围内（据我所知），我们已经满足了安全运输的要求。
import Cocoa
class Socket: NSObject {
private let hello = "Hello!"
private var socketfd: Int32
private var sock_addr: sockaddr
private var sslContext: SSLContext?
var sslWriteCallbackFunc: SSLWriteFunc {
get {
let ump = UnsafeMutablePointer<((SSLConnectionRef, UnsafePointer<Void>,
UnsafeMutablePointer<Int>) -> OSStatus)>.alloc(1)
ump.initialize(sslWriteCallback)
return CFunctionPointer<((SSLConnectionRef, UnsafePointer<Void>,
UnsafeMutablePointer<Int>) -> OSStatus)>(COpaquePointer(ump))
}
}
var sslReadCallbackFunc: SSLReadFunc {
get {
let ump = UnsafeMutablePointer<((SSLConnectionRef, UnsafeMutablePointer<Void>,
UnsafeMutablePointer<Int>) -> OSStatus)>.alloc(1)
ump.initialize(sslReadCallback)
return CFunctionPointer<((SSLConnectionRef, UnsafeMutablePointer<Void>,
UnsafeMutablePointer<Int>) -> OSStatus)>(COpaquePointer(ump))
}
}
init(address: String, port: UInt16) {
socketfd = Darwin.socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)
var addr = Darwin.sockaddr_in(sin_len: __uint8_t(sizeof(sockaddr_in)), sin_family: sa_family_t(AF_INET), sin_port: CFSwapInt16(port), sin_addr: in_addr(s_addr: inet_addr(address)), sin_zero: (0, 0, 0, 0, 0, 0, 0, 0))
sock_addr = Darwin.sockaddr(sa_len: 0, sa_family: 0, sa_data: (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0))
Darwin.memcpy(&sock_addr, &addr, Int(sizeof(sockaddr_in)))
super.init()
}
func connect() -> Socket {
let err = Darwin.connect(socketfd, &sock_addr, socklen_t(sizeof(sockaddr_in)))
return self
}
func makeSecure() -> Socket {
if let umc = SSLCreateContext(nil, kSSLClientSide, kSSLStreamType) {
sslContext = umc.takeRetainedValue()
var status = SSLSetIOFuncs(sslContext!, sslReadCallbackFunc, sslWriteCallbackFunc)
status = SSLSetConnection(sslContext!, &socketfd)
SSLHandshake(sslContext!)
}
return self
}
func sendHello() -> Socket {
let bytes = [UInt8](hello.utf8)
let data = NSData(bytes: bytes, length: bytes.count)
let test = UnsafeMutablePointer<Int>.alloc(1)
test.initialize(bytes.count)
self.sslWriteCallback(&socketfd, data: data.bytes, dataLength: test)
return self
}
// MARK: - SSL Callback Methods
func sslReadCallback(connection: SSLConnectionRef,
data: UnsafeMutablePointer<Void>,
dataLength: UnsafeMutablePointer<Int>) -> OSStatus {
let bytesRead = read(socketfd, data, UnsafePointer<Int>(dataLength).memory)
return noErr
}
func sslWriteCallback(connection: SSLConnectionRef,
data: UnsafePointer<Void>,
dataLength: UnsafeMutablePointer<Int>) -> OSStatus {
let sent = Darwin.sendto(socketfd, data, UnsafePointer<Int>(dataLength).memory, 0, &sock_addr, socklen_t(sizeof(sockaddr_in)))
if (sent < 0) {
let error = NSError(domain: NSPOSIXErrorDomain, code: Int(errno), userInfo: nil)
println(error.localizedDescription)
} else {
println("Sent \(sent) bytes (\(hello))")
}
return noErr
}
}
我通过制作一个简单的实例测试了非TLS套接字通信：
let socket = Socket(address: "some-ip-address", port: 8080)
socket.connect().sendHello()
使用netcat在目标计算机上运行echo服务器。这很好。
nc -l -p 8080
尝试将套接字包装在Secure Transport的TLS（调用makeSecure（）方法）时，在调用SSLHandshake（...）时出现EXC_BAD_ADDRESS（代码= 2，地址= ...）错误。有没有人知道我在这里失踪了什么？
修改
我可以看到Console推出：
04/06/15 09:20:48,000 kernel[0]: Data/Stack execution not permitted: TheProject[pid 29184] at virtual address 0x100602000, protections were read-write
编辑2
我在Xcode 7测试版中使用了Swift 2。见下文。
答案 0 :(得分：2)
从Xcode 7 beta附带的Swift 2开始，Swift中的功能指针工作并且已经大大简化了。我把上面的例子变成了这个，它起作用了：
import pandas
from numpy import nan
import numpy
dataGrid = pandas.DataFrame({1: {1: 1, 3: 2},
2: {1: 3, 3: 4}})
def getExtrapolatedInterpolatedValue(x, y):
global dataGrid
if x not in dataGrid.index:
dataGrid.ix[x] = nan
dataGrid = dataGrid.sort()
dataGrid = dataGrid.interpolate(method='index', axis=0).ffill(axis=0).bfill(axis=0)
if y not in dataGrid.columns.values:
dataGrid = dataGrid.reindex(columns=numpy.append(dataGrid.columns.values, y))
dataGrid = dataGrid.sort_index(axis=1)
dataGrid = dataGrid.interpolate(method='index', axis=1).ffill(axis=1).bfill(axis=1)
return dataGrid[y][x]
print getExtrapolatedInterpolatedValue(2, 1.4)
>>2.3
答案 1 :(得分：1)
Hans的回答似乎是不必要地分配内存。以下是Swift 3.1版本，其中包含更多错误检查和URL支持，并获取返回的通用名称（而不是实际读取或写入数据）。
func getCNforSSL(at url:URL, port:UInt16) -> String? {
var socketfd = Darwin.socket(AF_INET, SOCK_STREAM, IPPROTO_TCP)
guard let ip = urlToIP(url) else {
NSLog("Could not get IP from URL \(url)")
return nil
}
let inAddr = in_addr(s_addr: inet_addr(ip))
var addr = sockaddr_in(sin_len: __uint8_t(MemoryLayout<sockaddr_in>.size),
sin_family: sa_family_t(AF_INET),
sin_port: CFSwapInt16(port),
sin_addr: inAddr,
sin_zero: (0, 0, 0, 0, 0, 0, 0, 0))
var sock_addr = sockaddr(sa_len: 0,
sa_family: 0,
sa_data: (0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0, 0))
_ = memcpy(&sock_addr, &addr, MemoryLayout<sockaddr_in>.size)
guard connect(socketfd, &sock_addr, socklen_t(MemoryLayout<sockaddr_in>.size)) == 0 else {
NSLog("Failed connection for \(url) port \(port) with error \(Darwin.errno)")
return nil
}
defer {
if close(socketfd) != 0 {
NSLog("Error closing socket for \(url) port \(port) with error \(Darwin.errno)")
}
}
guard let sslContext = SSLCreateContext(kCFAllocatorDefault, .clientSide, .streamType) else {
NSLog("Could not create SSL Context for \(url) port \(port)")
return nil
}
defer {
SSLClose(sslContext)
}
SSLSetIOFuncs(sslContext, sslReadCallback, sslWriteCallback)
SSLSetConnection(sslContext, &socketfd)
SSLSetSessionOption(sslContext, .breakOnServerAuth, true)
var secTrust:SecTrust? = nil
var status:OSStatus = 0
var subject:String? = nil
repeat {
status = SSLHandshake(sslContext)
if status == errSSLPeerAuthCompleted {
SSLCopyPeerTrust(sslContext, &secTrust)
if let trust = secTrust {
// 0 always garunteed to exist
let cert = SecTrustGetCertificateAtIndex(trust, 0)!
subject = SecCertificateCopySubjectSummary(cert) as String?
}
}
} while status == errSSLWouldBlock
guard status == errSSLPeerAuthCompleted else {
NSLog("SSL Handshake Error for \(url) port \(port) OSStatus \(status)")
return nil
}
return subject
}
func sslReadCallback(connection: SSLConnectionRef,
data: UnsafeMutableRawPointer,
dataLength: UnsafeMutablePointer<Int>) -> OSStatus {
let socketfd = connection.load(as: Int32.self)
let bytesRequested = dataLength.pointee
let bytesRead = read(socketfd, data, UnsafePointer<Int>(dataLength).pointee)
if (bytesRead > 0) {
dataLength.initialize(to: bytesRead)
if bytesRequested > bytesRead {
return Int32(errSSLWouldBlock)
} else {
return noErr
}
} else if (bytesRead == 0) {
dataLength.initialize(to: 0)
return Int32(errSSLClosedGraceful)
} else {
dataLength.initialize(to: 0)
switch (errno) {
case ENOENT: return Int32(errSSLClosedGraceful)
case EAGAIN: return Int32(errSSLWouldBlock)
case ECONNRESET: return Int32(errSSLClosedAbort)
default: return Int32(errSecIO)
}
}
}
func sslWriteCallback(connection: SSLConnectionRef,
data: UnsafeRawPointer,
dataLength: UnsafeMutablePointer<Int>) -> OSStatus {
let socketfd = connection.load(as: Int32.self)
let bytesToWrite = dataLength.pointee
let bytesWritten = write(socketfd, data, UnsafePointer<Int>(dataLength).pointee)
if (bytesWritten > 0) {
dataLength.initialize(to: bytesWritten)
if (bytesToWrite > bytesWritten) {
return Int32(errSSLWouldBlock)
} else {
return noErr
}
} else if (bytesWritten == 0) {
dataLength.initialize(to: 0)
return Int32(errSSLClosedGraceful)
} else {
dataLength.initialize(to: 0)
if (EAGAIN == errno) {
return Int32(errSSLWouldBlock)
} else {
return Int32(errSecIO)
}
}
}
private func urlToIP(_ url:URL) -> String? {
guard let hostname = url.host else {
return nil
}
guard let host = hostname.withCString({gethostbyname($0)}) else {
return nil
}
guard host.pointee.h_length > 0 else {
return nil
}
var addr = in_addr()
memcpy(&addr.s_addr, host.pointee.h_addr_list[0], Int(host.pointee.h_length))
guard let remoteIPAsC = inet_ntoa(addr) else {
return nil
}
return String.init(cString: remoteIPAsC)
}
答案 2 :(得分：0)
我问网络大师同行你的问题;这是他的回答：
此人是SOL，因为Secure Transport要求您实现C函数回调，而Swift目前不支持。
我建议开发人员使用CFSocketStream，它负责TLS并且可以从Swift轻松调用。请参阅TLSTool示例代码。