mac: lock control socket to team-signed peers

This commit is contained in:
Peter Steinberger
2025-12-12 01:22:24 +00:00
parent f1ff24d634
commit 491fd6b74d

View File

@@ -8,6 +8,7 @@ final actor ControlSocketServer {
private var listenFD: Int32 = -1
private var source: DispatchSourceRead?
private let maxRequestBytes = 512 * 1024
private let allowedTeamIDs: Set<String> = ["Y5PE65HELJ"]
func start() {
// Already running
@@ -82,6 +83,8 @@ final actor ControlSocketServer {
}
private func handleClient(fd: Int32) async {
guard self.isAllowed(fd: fd) else { return }
var data = Data()
var buffer = [UInt8](repeating: 0, count: 16 * 1024)
let bufSize = buffer.count
@@ -115,4 +118,49 @@ final actor ControlSocketServer {
}
}
}
private func isAllowed(fd: Int32) -> Bool {
var pid: pid_t = 0
var pidSize = socklen_t(MemoryLayout<pid_t>.size)
let r = getsockopt(fd, SOL_LOCAL, LOCAL_PEERPID, &pid, &pidSize)
guard r == 0, pid > 0 else { return false }
// Same-user quick check
if let callerUID = self.uid(for: pid), callerUID == getuid() {
return true
}
return self.teamIDMatches(pid: pid)
}
private func uid(for pid: pid_t) -> uid_t? {
var info = kinfo_proc()
var size = MemoryLayout.size(ofValue: info)
var mib: [Int32] = [CTL_KERN, KERN_PROC, KERN_PROC_PID, pid]
let ok = mib.withUnsafeMutableBufferPointer { mibPtr -> Bool in
return sysctl(mibPtr.baseAddress, u_int(mibPtr.count), &info, &size, nil, 0) == 0
}
return ok ? info.kp_eproc.e_ucred.cr_uid : nil
}
private func teamIDMatches(pid: pid_t) -> Bool {
let attrs: NSDictionary = [kSecGuestAttributePid: pid]
var secCode: SecCode?
guard SecCodeCopyGuestWithAttributes(nil, attrs, SecCSFlags(), &secCode) == errSecSuccess,
let code = secCode else { return false }
var staticCode: SecStaticCode?
guard SecCodeCopyStaticCode(code, SecCSFlags(), &staticCode) == errSecSuccess,
let sCode = staticCode else { return false }
var infoCF: CFDictionary?
guard SecCodeCopySigningInformation(sCode, SecCSFlags(), &infoCF) == errSecSuccess,
let info = infoCF as? [String: Any],
let teamID = info[kSecCodeInfoTeamIdentifier as String] as? String
else {
return false
}
return self.allowedTeamIDs.contains(teamID)
}
}