SCDynamicStoreSetValue returns false - macos

I tried updating the proxy settings of my mac. SCDynamicStoreSetValue: returned false, indicating an unsuccessful update. This is the code I use. What is the correct way?
let ds: SCDynamicStoreRef = SCDynamicStoreCreate(nil, "setProxy" as CFString, nil, nil)!
let isUpdated = SCDynamicStoreSetValue(ds, "HTTPProxy" as CFStringRef, "111.111.111.1")
if isUpdated{
print("updated")
}else{
print("not updated")
}
The question is about why SCDynamicStoreSetValue returns false and how to circumvent it.

After SCDynamicStoreSetValue fails, call SCError() to obtain the error code:
let errorCode = SCError()
Or obtain the error as a string with:
let errorString = String.fromCString(SCErrorString(SCError()))
In either case, review the Status and Error Codes for the System Configuration Framework. That should provide you with the reason that SCDynamicStoreSetValue is returning false.
(If your app is Sandboxed, the likely reason is kSCStatusAccessError, or "Permission Denied". Sandboxed apps can't set those values.)

I know this is an old topic, but the third argument of SCDynamicStoreSetValue should be a CFPropertyListRef (in our case a CFString, not a string), as in the docs
In my case this was causing the function call fail.

Related

Calling Wow64GetThreadContext returns the error "When the file already exists, the file cannot be created."

I am using Wow64GetThreadContext calling from a 64bit process on a 32 bit process. I am catching the WOW64 Context structure with this method.
The MSDN seems to no longer have the documentation for this method available, it is however still referenced on the GetThreadContext documentation page. I am not sure why this is. As the documentation is not available I am having a hard time figuring out why I am getting the error below.
The code where the error is being thrown is below. The error being thrown when I check GetLastWin32Error is: When the file already exists, the file cannot be created.
Does anyone have any ideas why it would throw this error? I am not creating a file at all which is confusing me.
ContextWow = new WOW_CONTEXT();
ContextWow.ContextFlags = CONTEXT_FLAGS.CONTEXT_ALL;
try
{
Wow64GetThreadContext(ThreadHandle, ref ContextWow);
if (new Win32Exception(Marshal.GetLastWin32Error()).Message != "The operation completed successfully")
{
throw new Exception("Win32 Exception encountered when attempting to get thread context" + new Win32Exception(Marshal.GetLastWin32Error()).Message);
}
}
Here is a link to the documentation you want, captured by the Internet Archive on July 10 2019:
Wow64GetThreadContext() function
Per the documentation:
Return Value
If the function succeeds, the return value is nonzero.
If the function fails, the return value is zero. To get extended error information, call GetLastError.
Your error handling is wrong. It is the equivalent of doing the following:
ContextWow = new WOW_CONTEXT();
ContextWow.ContextFlags = CONTEXT_FLAGS.CONTEXT_ALL;
try
{
Wow64GetThreadContext(ThreadHandle, ref ContextWow);
if (Marshal.GetLastWin32Error() != 0)
{
throw new Exception("Win32 Exception encountered when attempting to get thread context" + new Win32Exception().Message);
}
}
You are making a very common mistake of calling GetLastError() at the wrong time. As the documentation says, the Win32 error code is valid to use only if Wow64GetThreadContext() returns false, which you are not checking for.
What you are doing is not the correct way to check for an error (either to get the error code, or to perform comparisons on it). The correct code should look more like the following instead:
ContextWow = new WOW_CONTEXT();
ContextWow.ContextFlags = CONTEXT_FLAGS.CONTEXT_ALL;
if (!Wow64GetThreadContext(ThreadHandle, ref ContextWow))
{
throw new Exception("Error encountered when attempting to get thread context", new Win32Exception());
}
That being said, the error message you are seeing, "When the file already exists, the file cannot be created", is your system's text for the ERROR_ALREADY_EXISTS (183) error code, which is not an error code that Wow64GetThreadContext() is documented as reporting on failure, and really just doesn't make much sense for this kind of function to report on failure. So, what is most likely happening is that Wow64GetThreadContext() is actually returning true, but because you are not checking for failure correctly, you are actually seeing an error code from an earlier/internal API call that has not been overwritten when Wow64GetThreadContext() returns true, and so it should be ignored in this situation, not acted on.

Function with record as argument

I know this is very basic, but it's driving me up a wall:
peercert is defined as:
peercert(Socket) -> {ok, Cert} | {error, Reason}
Types
Socket = sslsocket()
Cert = binary()
The peer certificate is returned as a DER-encoded binary. The certificate can be decoded with public_key:pkix_decode_cert/2.
Ok, great. sslsocket is defined as -record(sslsocket, {fd = nil, pid = nil})
So I run :
New = #sslsocket{pid = Pid},
io:fwrite("~n~npeercert~p~n~n", [ssl:peercert(New)]).
But I get an error that
no function clause matching ssl:peercert({sslsocket,<0.1277.0>,undefined})
So I run it with Pid as an argument and get a similar error:
no function clause matching ssl:peercert(<0.1277.0>)
I'm totally stumped here. I had it working before, the function says it takes these as arguments...
Thank you for your help in advance!
sslsocket() type is not a record called sslsocket, otherwise it would be written as #sslsocket{}. It's a "black box type" (its real type is an implementation detail), but you can obtain it from function ssl:connect().

XPC Service returning NSAttributtedString

I have a huge problem to transfer NSAttributtedString in a block callback from XPC service.
I am trying to return basic string as:
NSDictionary *arrayComa = #{NSForegroundColorAttributeName:[NSColor colorWithRGB:0xD35250],
NSFontAttributeName:[NSFont fontWithName:#"Monaco" size:11]};
NSMutableAttributedString *testString = [[NSMutableAttributedString alloc] initWithString:#"{}" attributes:arrayComa];
I have also whitelisted the incoming response as:
let incommingClasses:Set = Set(arrayLiteral: [NSMutableAttributedString.self, NSAttributedString.self, NSColor.self, NSFont.self, NSString.self, ])
connectionService.remoteObjectInterface?.setClasses(incommingClasses, forSelector: attributtedText:withReply:, argumentIndex: 0, ofReply: true)
What ever I do I get Errors:
Exception caught during decoding of received reply to message 'Exception caught during decoding of received reply to message 'attributtedText:withReply':, dropping incoming message and calling failure block.
Exception: Exception while decoding argument 0 (#1 of invocation):
<NSInvocation: 0x6000006649c0>
return value: {v} void
target: {#?} 0x0 (block)
argument 1: {#"NSMutableAttributedString"} 0x0
Exception: value for key '<no key>' was of unexpected class 'NSMutableAttributedString'. Allowed classes are '{(
(
NSMutableAttributedString,
NSAttributedString,
NSColor,
NSFont,
NSString
)
)}'.
Anybody has transferred NSAttributtedText via XPC Service succesfully?
EDIT: I got a reply to my message on devforums, a workaround is to use an NSSet and to cast it as Set when passing to to setClasses(). Another issue is that there already are pre-set classes for all selectors, and therefore you need to add your own to the current ones, rather than set yours only. Here's a working code :
let interface = NSXPCInterface(withProtocol: MyProtocol.self)
let expectedClasses = NSSet.setWithArray([[NSMutableAttributedString.self, NSAttributedString.self, NSColor.self, NSFont.self])
let currentExpectedClasses = interface.classesForSelector("attributtedText:withReply:", argumentIndex: 0, ofReply: false) as NSSet
let allClasses = currentExpectedClasses.setByAddingSet(expectedClasses)
interface.setClasses(allClasses as Set<NSObject>, forSelector: "attributtedText:withReply:", argumentIndex: 0, ofReply: false)
Original answer :
This will only be a partial answer as I haven't found the right way to do this either yet, but
let incommingClasses:Set = Set(arrayLiteral: [NSMutableAttributedString.self, NSAttributedString.self, NSColor.self, NSFont.self, NSString.self, ])
returns a Set<NSArray>, which is not what you want. I assume you added the 'arrayLiteral' argument label because the compiler told you so, however this compiles :
let foo = Set(["string1", "string2"])
and it returns a Set<String>.
The problem is that I couldn't find a way to create a Set of class types. I've asked on Apple's devforums : https://devforums.apple.com/thread/271316 but unless I'm missing something obvious, this looks like an API bug.

SecSignVerifyTransform crashing in Swift with CSSM error Code=-2147415790

I'm trying to obtain a digital signature for a XML string using a RSA private key using Swift as command-line script (to be called from FileMaker later).
The compiler kept crashing with "segmentation fault 11" and then "Illegal Instruction: 4" and I kept drilling down until I (think) I found the problem, but it's completely beyond me, so please, please help!! ;) :)
As the title says, when I invoke SecTransformExecute on my SecSignTransform, with a binary version of my String as input attribute, I get the following error message:
Error Domain=Internal CSSM error Code=-2147415790 "The operation
couldn’t be completed. (Internal CSSM error error -2147415790 -
Internal error #80010912 at __SignTransform_block_invoke_2
/SourceCache/Security/Security-57031.1.35/Security/libsecurity_transform/lib/SecSignVerifyTransform.c:279)" UserInfo=0x7fc620e23aa0 {NSDescription=Internal error #80010912 at
__SignTransform_block_invoke_2 /SourceCache/Security/Security-57031.1.35/Security/libsecurity_transform/lib/SecSignVerifyTransform.c:279,
Originating Transform=CoreFoundationObject}
Here is the relevant part of my code:
import Foundation
import CoreFoundation
import Security
var signer: SecTransformRef
var signedData, digestData: NSData
var error: Unmanaged<CFErrorRef>?
var status: OSStatus
var key: SecKey
var anyItem: Unmanaged<AnyObject>?
var keySearchDict: [String : AnyObject]
let keyMatch = "[*place search tag here*]" as String
// turns a string into a binary to sign
let str = "Hello World"
let uintData = [UInt8](str.utf8)
let sourceData = CFDataCreate(kCFAllocatorDefault, uintData, countElements(uintData))
// sets up keySearchDict to query Keychain
keySearchDict = [(kSecClass as String): (kSecClassKey as String), (kSecMatchSubjectContains as String): keyMatch, (kSecReturnRef as String): kCFBooleanTrue]
// gets private key using keySearchDict
status = SecItemCopyMatching(keySearchDict, &anyItem)
key = (anyItem!.takeRetainedValue() as SecKey)
if status != 0 { println("status is: \(SecCopyErrorMessageString(status, &error).takeRetainedValue())") }
// creates SecTransform object using key
signer = SecSignTransformCreate(key, &error).takeRetainedValue()
if error == nil { println("signer transform creation error == nil") } else { println(error) }
// signer to get data from sourceData
SecTransformSetAttribute(signer, kSecTransformInputAttributeName, sourceData!, &error)
if error == nil { println("signer attribute setting error == nil") } else { println(error) }
// execute the transform
//signedData = (SecTransformExecute(signer, &error) as NSData)
let anything = SecTransformExecute(signer, &error)
if error == nil { println("signer execute error == nil") } else { println("erro: \(error!.takeRetainedValue())"); println(CFErrorGetCode(error!.takeRetainedValue())) }
println("anything = \(anything)")
//println(signedData)
I'm not very familiar with objc and actually not quite a proper coder, so please forgive my poor coding style ;) Also, sorry if I'm posting too much of it, but I figured better more than less...
Maybe I'm doing something wrong when transforming the String to binary for signing? I tried it both using CFData and NSData (to make this self contained, I'm using "Hello World" as my String, but in my code I actually load a UTF8 encoded XML from a file using NSData(contentsOfFile:) yet both generate the same error...)
Thanks you so much for your help! It's being a great learning experience, but I've been at it for over a week full-time now, so I really can use a break!! ;) :D
I have found a solution. The code no longer crashes, and I connected to the web service successfully after it, and the XMLDSIG signature was accepted by it (see related Question on XMLDSIG if interested in details on canonicalization and xml reference).
The key I was using is not compatible with signing (not sure why or even what the key was, actually...)
I was looking into counter-authenticating with a server using a X509 certificate (for an unrelated part of my solution) when I came across the SecIdentity class, needed to create a SecCredential together with the certificate and authenticate with the server.
I saw Identities embed a private key, and thought if could work for me. And it did!
Here are the changes I made:
Changed the kSecClass to kSecClassIdentity in the search dictionary
Retrieved the SecIdentity using SecItemCopyMatching
After casting it accordingly, used SecIdentityCopyPrivateKey to retrieve the private key into a SecKeyRef
Used this key in SecSignTransform, and voilà!! It worked!
Here is the working code:
// ...
// get the SecIdentity (substitutes KeySearchDict etc)
idSearchDict = [(kSecClass as String): (kSecClassIdentity as String), (kSecMatchSubjectContains as String): keyMatch, (kSecReturnRef as String):
status = SecItemCopyMatching(idSearchDict, &anyItem)
id = (anyItem!.takeRetainedValue() as SecIdentity)
// Retrieve the private key from SecIdentity
var KeyRef: Unmanaged<SecKeyRef>?
SecIdentityCopyPrivateKey(id, &KeyRef)
priKey = (KeyRef!.takeRetainedValue() as SecKey)
// Create SecSign using the private key
signer = SecSignTransformCreate(priKey, &error).takeRetainedValue()
if error != nil { print("signer transform creation error: ") ; println(error) }
/ signer to get data from sourceData
// ...
I'll post another question with the difficulties I'm facing with XMLDSIG, and add it to the comments, in case anyone is interested. I've already solved that too, and the answer is there in case you need it.
Thanks to everyone who tried to help, and hope this saves someone a lot of time and headache in the future!!
PS: loving Swift, otherwise 😉 😃

Cocoa Authorization in Swift

This is my first time writing in Swift, Cocoa (have experience in Cocoa Touch), and using Authorization, so I honestly have no idea if I am even on the right track. I am trying to make a modification to the hosts file, which requires user authentication, but both the AuthorizationCreate and AuthorizationExecuteWithPrivileges methods are giving errors.
var authorizationRef:AuthorizationRef
var status:OSStatus
status = AuthorizationCreate(nil, environment:kAuthorizationEmptyEnvironment, flags:kAuthorizationFlagDefaults, authorization:&authorizationRef)
let overwrite_hosts = "echo \(hostsContents) > /private/etc/hosts"
let args = [overwrite_hosts.cStringUsingEncoding(NSUTF8StringEncoding)]
status = AuthorizationExecuteWithPrivileges(authorizationRef, pathToTool:"/bin/sh", options:kAuthorizationFlagDefaults, arguments:args, communicationsPipe:nil)
Me calling AuthorizationCreate is throwing "Type '()' does not conform to protocol 'AuthorizationRef'" and my call of AuthorizationExecuteWithPrivileges is throwing "Could not find an overload for '__conversion' that accepts the supplied arguments"
Any ideas? Am I approaching this incorrectly?
Thanks for any help!
I was able to figure out how to do it via AppleScript, but you should be able to do it using the Authorization method I was trying before, therefore leaving this question open. Anybody looking for a quick solution (no error checks implemented) you can use what I wrote below:
func doScriptWithAdmin(inScript:String) -> String{
let script = "do shell script \"\(inScript)\" with administrator privileges"
var appleScript = NSAppleScript(source: script)
var eventResult = appleScript.executeAndReturnError(nil)
if !eventResult {
return "ERROR"
}else{
return eventResult.stringValue
}
}

Resources