From 119d2f02e4478ea1a33dd56d845a536c35e2624c Mon Sep 17 00:00:00 2001
From: Davide De Rosa <keeshux@gmail.com>
Date: Sun, 3 Jan 2021 00:44:42 +0100
Subject: [PATCH] Add OpenVPN dataCiphers field

---
 .../Protocols/OpenVPN/Configuration.swift     |  8 +++++++
 .../OpenVPN/ConfigurationParser.swift         | 23 +++++++++++++++----
 2 files changed, 27 insertions(+), 4 deletions(-)

diff --git a/TunnelKit/Sources/Protocols/OpenVPN/Configuration.swift b/TunnelKit/Sources/Protocols/OpenVPN/Configuration.swift
index 3b94188..26cd931 100644
--- a/TunnelKit/Sources/Protocols/OpenVPN/Configuration.swift
+++ b/TunnelKit/Sources/Protocols/OpenVPN/Configuration.swift
@@ -178,6 +178,9 @@ extension OpenVPN {
         /// The cipher algorithm for data encryption.
         public var cipher: Cipher?
         
+        /// The set of supported cipher algorithms for data encryption (2.5.).
+        public var dataCiphers: [Cipher]?
+        
         /// The digest algorithm for HMAC.
         public var digest: Digest?
         
@@ -298,6 +301,7 @@ extension OpenVPN {
         public func build() -> Configuration {
             return Configuration(
                 cipher: cipher,
+                dataCiphers: dataCiphers,
                 digest: digest,
                 compressionFraming: compressionFraming,
                 compressionAlgorithm: compressionAlgorithm,
@@ -355,6 +359,9 @@ extension OpenVPN {
         /// - Seealso: `ConfigurationBuilder.cipher`
         public let cipher: Cipher?
         
+        /// - Seealso: `ConfigurationBuilder.dataCiphers`
+        public let dataCiphers: [Cipher]?
+        
         /// - Seealso: `ConfigurationBuilder.digest`
         public let digest: Digest?
         
@@ -476,6 +483,7 @@ extension OpenVPN.Configuration {
     public func builder() -> OpenVPN.ConfigurationBuilder {
         var builder = OpenVPN.ConfigurationBuilder()
         builder.cipher = cipher
+        builder.dataCiphers = dataCiphers
         builder.digest = digest
         builder.compressionFraming = compressionFraming
         builder.compressionAlgorithm = compressionAlgorithm
diff --git a/TunnelKit/Sources/Protocols/OpenVPN/ConfigurationParser.swift b/TunnelKit/Sources/Protocols/OpenVPN/ConfigurationParser.swift
index 6a15ae7..700db47 100644
--- a/TunnelKit/Sources/Protocols/OpenVPN/ConfigurationParser.swift
+++ b/TunnelKit/Sources/Protocols/OpenVPN/ConfigurationParser.swift
@@ -42,6 +42,8 @@ extension OpenVPN {
             
             static let cipher = NSRegularExpression("^cipher +[^,\\s]+")
             
+            static let dataCiphers = NSRegularExpression("^(data-ciphers|ncp-ciphers) +[^,\\s]+(:[^,\\s]+)*")
+            
             static let auth = NSRegularExpression("^auth +[\\w\\-]+")
             
             static let compLZO = NSRegularExpression("^comp-lzo.*")
@@ -199,6 +201,7 @@ extension OpenVPN {
             var currentBlockName: String?
             var currentBlock: [String] = []
             
+            var optDataCiphers: [Cipher]?
             var optCipher: Cipher?
             var optDigest: Digest?
             var optCompressionFraming: CompressionFraming?
@@ -345,8 +348,19 @@ extension OpenVPN {
                         return
                     }
                     optCipher = Cipher(rawValue: rawValue.uppercased())
-                    if optCipher == nil {
-                        unsupportedError = ConfigurationError.unsupportedConfiguration(option: "cipher \(rawValue)")
+                }
+                Regex.dataCiphers.enumerateArguments(in: line) {
+                    isHandled = true
+                    guard let rawValue = $0.first else {
+                        return
+                    }
+                    let rawCiphers = rawValue.components(separatedBy: ":")
+                    optDataCiphers = []
+                    rawCiphers.forEach {
+                        guard let cipher = Cipher(rawValue: $0.uppercased()) else {
+                            return
+                        }
+                        optDataCiphers?.append(cipher)
                     }
                 }
                 Regex.auth.enumerateArguments(in: line) {
@@ -610,8 +624,8 @@ extension OpenVPN {
                 guard let _ = optCA else {
                     throw ConfigurationError.missingConfiguration(option: "ca")
                 }
-                guard let _ = optCipher else {
-                    throw ConfigurationError.missingConfiguration(option: "cipher")
+                guard optCipher != nil || !(optDataCiphers?.isEmpty ?? false) else {
+                    throw ConfigurationError.missingConfiguration(option: "cipher or data-ciphers")
                 }
             }
             
@@ -622,6 +636,7 @@ extension OpenVPN {
             // MARK: General
             
             sessionBuilder.cipher = optCipher
+            sessionBuilder.dataCiphers = optDataCiphers
             sessionBuilder.digest = optDigest
             sessionBuilder.compressionFraming = optCompressionFraming
             sessionBuilder.compressionAlgorithm = optCompressionAlgorithm