[xaprepare] Make 7zip work with "dangerous" symlinks in ZIPs

build-tools/xaprepare/xaprepare/Application/RegexProgramVersionParser.cs

@@ -12,78 +12,78 @@ namespace Xamarin.Android.Prepare
 	///   <see cref="VersionOutputLine"/> is set to any other value only that line is taken into consideration. This is
 	///   done to make processing less ambiguous and faster.
 	/// </summary>
-    class RegexProgramVersionParser : ProgramVersionParser
-    {
-	    const string VersionGroupName = "Version";
-	    static readonly char[] LineSeparator = new [] { '\n' };
+	class RegexProgramVersionParser : ProgramVersionParser
+	{
+		public const string VersionGroupName = "Version";
+		public static readonly char[] LineSeparator = new [] { '\n' };
 
-	    Regex rx;
+		Regex rx;
 
-	    public RegexProgramVersionParser (string programName, string versionArguments, Regex regex, uint versionOutputLine = 0, Log? log = null)
-		    : base (programName, versionArguments, versionOutputLine, log)
-	    {
-		    if (regex == null)
-			    throw new ArgumentNullException (nameof (regex));
-		    rx = regex;
-	    }
+		public RegexProgramVersionParser (string programName, string versionArguments, Regex regex, uint versionOutputLine = 0, Log? log = null)
+		: base (programName, versionArguments, versionOutputLine, log)
+		{
+			if (regex == null)
+			throw new ArgumentNullException (nameof (regex));
+			rx = regex;
+		}
 
-	    public RegexProgramVersionParser (string programName, string versionArguments, string regex, uint versionOutputLine = 0, Log? log = null)
-		    : base (programName, versionArguments, versionOutputLine, log)
-	    {
-		    if (String.IsNullOrEmpty (regex))
-			    throw new ArgumentException ("must not be null or empty", nameof (regex));
+		public RegexProgramVersionParser (string programName, string versionArguments, string regex, uint versionOutputLine = 0, Log? log = null)
+		: base (programName, versionArguments, versionOutputLine, log)
+		{
+			if (String.IsNullOrEmpty (regex))
+			throw new ArgumentException ("must not be null or empty", nameof (regex));
 
-		    rx = new Regex (regex, RegexOptions.Compiled);
-	    }
+			rx = new Regex (regex, RegexOptions.Compiled);
+		}
 
-        protected override string ParseVersion (string programOutput)
-        {
-	        string output = programOutput.Trim ();
-	        if (String.IsNullOrEmpty (output)) {
-		        Log.WarningLine ($"Unable to parse version of {ProgramName} because version output was empty");
-		        return DefaultVersionString;
-	        }
+		protected override string ParseVersion (string programOutput)
+		{
+			string output = programOutput.Trim ();
+			if (String.IsNullOrEmpty (output)) {
+				Log.WarningLine ($"Unable to parse version of {ProgramName} because version output was empty");
+				return DefaultVersionString;
+			}
 
-	        string ret = String.Empty;
-	        string[] lines = programOutput.Split (LineSeparator);
-	        if (VersionOutputLine > 0) {
-		        if (lines.Length < VersionOutputLine) {
-			        Log.WarningLine ($"Not enough lines in version output of {ProgramName}: version number was supposed to be found on line {VersionOutputLine} but there are only {lines.Length} lines");
-			        return DefaultVersionString;
-		        }
+			string ret = String.Empty;
+			string[] lines = programOutput.Split (LineSeparator);
+			if (VersionOutputLine > 0) {
+				if (lines.Length < VersionOutputLine) {
+					Log.WarningLine ($"Not enough lines in version output of {ProgramName}: version number was supposed to be found on line {VersionOutputLine} but there are only {lines.Length} lines");
+					return DefaultVersionString;
+				}
 
-		        if (TryMatch (lines [VersionOutputLine - 1], out ret) && !String.IsNullOrEmpty (ret)) {
-			        return ret;
-		        }
+				if (TryMatch (rx, lines [VersionOutputLine - 1], out ret) && !String.IsNullOrEmpty (ret)) {
+					return ret;
+				}
 
-		        return DefaultVersionString;
-	        }
+				return DefaultVersionString;
+			}
 
-	        foreach (string line in lines) {
-		        if (TryMatch (line, out ret))
-			        break;
-	        }
+			foreach (string line in lines) {
+				if (TryMatch (rx, line, out ret))
+				break;
+			}
 
-	        return ret ?? DefaultVersionString;
-        }
+			return ret ?? DefaultVersionString;
+		}
 
-	    bool TryMatch (string line, out string version)
-	    {
-		    version = String.Empty;
+		public static bool TryMatch (Regex regex, string line, out string version)
+		{
+			version = String.Empty;
 
-		    Match match = rx.Match (line);
-		    if (!match.Success || match.Groups.Count <= 0) {
-			    return false;
-		    }
+			Match match = regex.Match (line);
+			if (!match.Success || match.Groups.Count <= 0) {
+				return false;
+			}
 
-		    foreach (Group group in match.Groups) {
-			    if (String.Compare (group.Name, VersionGroupName, StringComparison.OrdinalIgnoreCase) == 0) {
-				    version = group.Value;
-				    return true;
-			    }
-		    }
+			foreach (Group group in match.Groups) {
+				if (String.Compare (group.Name, VersionGroupName, StringComparison.OrdinalIgnoreCase) == 0) {
+					version = group.Value;
+					return true;
+				}
+			}
 
-		    return false;
-	    }
-    }
+			return false;
+		}
+	}
 }

build-tools/xaprepare/xaprepare/Application/SevenZipVersionParser.cs

@@ -0,0 +1,70 @@
+using System;
+using System.Text.RegularExpressions;
+
+namespace Xamarin.Android.Prepare;
+
+class SevenZipVersionParser : ProgramVersionParser
+{
+	const string VersionArgument = "--help";
+	readonly Regex fallbackRegex;
+	readonly Regex modernRegex;
+
+	public SevenZipVersionParser (string programName, Regex fallbackRegex, Log? log = null)
+		: base (programName, VersionArgument, 0, log)
+	{
+		this.fallbackRegex = fallbackRegex;
+		modernRegex = VersionFetchers.MakeRegex (@"^7-Zip (\(a\) ){0,1}(?<Version>[\d]+\.[\d]+)");
+	}
+
+	protected override string ParseVersion (string programOutput)
+	{
+		string output = programOutput.Trim ();
+		if (String.IsNullOrEmpty (output)) {
+			Log.WarningLine ($"Unable to parse version of {ProgramName} because version output was empty");
+			return DefaultVersionString;
+		}
+
+		string ret = String.Empty;
+		string[] lines = programOutput.Split (RegexProgramVersionParser.LineSeparator);
+
+		// First try to find the official 7zip release version
+		foreach (string l in lines) {
+			string line = l.Trim ();
+
+			if (line.Length == 0) {
+				continue;
+			}
+
+			if (line.StartsWith ("7-Zip", StringComparison.OrdinalIgnoreCase)) {
+				// Strings of the form:
+				//   7-Zip 23.01 (x64) : Copyright (c) 1999-2023 Igor Pavlov : 2023-06-20
+				//   7-Zip (a) 23.01 (x64) : Copyright (c) 1999-2023 Igor Pavlov : 2023-06-20
+				//   7-Zip (a) 18.01 (x64) : Copyright (c) 1999-2018 Igor Pavlov : 2018-01-28
+				//   7-Zip (a) 18.01 (x86) : Copyright (c) 1999-2018 Igor Pavlov : 2018-01-28
+				if (RegexProgramVersionParser.TryMatch (modernRegex, line, out ret)) {
+					return ret;
+				}
+			}
+
+			// Since we know we're dealing with `--help` option output, we can short-circuit things
+			if (line.StartsWith ("Usage:", StringComparison.OrdinalIgnoreCase)) {
+				break;
+			}
+		}
+
+		// Modern version wasn't found, try again with the fallback one
+		foreach (string l in lines) {
+			string line = l.Trim ();
+
+			if (line.Length == 0) {
+				continue;
+			}
+
+			if (RegexProgramVersionParser.TryMatch (fallbackRegex, line, out ret)) {
+				return ret;
+			}
+		}
+
+		return DefaultVersionString;
+	}
+}

build-tools/xaprepare/xaprepare/Application/VersionFetchers.cs

@@ -18,7 +18,7 @@ class VersionFetchers
 
 		public Dictionary<string, ProgramVersionParser> Fetchers => GetFetchers ();
 
-		static Regex MakeRegex (string regex)
+		internal static Regex MakeRegex (string regex)
 		{
 			return new Regex (regex, RegexOptions.Compiled | RegexOptions.Singleline);
 		}
@@ -30,8 +30,11 @@ static Regex MakeRegex (string regex)
 					return fetchers;
 
 				fetchers = new Dictionary <string, ProgramVersionParser> (Context.Instance.OS.DefaultStringComparer) {
-					{"7z",       "--help",    MakeRegex ($"Version {StandardVersionRegex}"),   3},
-					{"7za",      "--help",    MakeRegex ($"Version {StandardVersionRegex}"),   3},
+					// Program-specific parsers
+					{"7z",       new SevenZipVersionParser ("7z", MakeRegex ($"Version {StandardVersionRegex}"))},
+					{"7za",      new SevenZipVersionParser ("7za", MakeRegex ($"Version {StandardVersionRegex}"))},
+
+					// Regex parsers
 					{"autoconf", "--version", StandardVersionAtEOL,                            1},
 					{"automake", "--version", StandardVersionAtEOL,                            1},
 					{"brew",     "--version", MakeRegex ($"^Homebrew {StandardVersionRegex}"), 1},

build-tools/xaprepare/xaprepare/ToolRunners/SevenZipRunner.cs

@@ -10,6 +10,10 @@ partial class SevenZipRunner : ToolRunner
 	{
 		const double DefaultTimeout = 30; // minutes
 		static readonly Version bsoepMinVersion = new Version (15, 5);
+
+		// Just an educated guess.  The official download page had versions 19 and then 23+ available
+		// and the 19 one didn't support the `-snld` switch
+		static readonly Version snldMinVersion = new Version (20, 0);
 		Version version;
 
 		protected override string DefaultToolExecutableName => "7za";
@@ -36,6 +40,7 @@ public async Task<bool> Extract (string archivePath, string outputDirectory, Lis
 				throw new ArgumentException ("must not be null or empty", nameof (outputDirectory));
 
 			ProcessRunner runner = CreateProcessRunner ("x");
+
 			AddStandardArguments (runner);
 			AddArguments (runner, extraArguments);
 			runner.AddQuotedArgument ($"-o{outputDirectory}");
@@ -114,6 +119,18 @@ protected override TextWriter CreateLogSink (string? logFilePath)
 
 		void AddStandardArguments (ProcessRunner runner)
 		{
+			Log.DebugLine ($"7-zip standard arguments, for 7z version {version}");
+
+			// Ignore some "dangerous" symbolic symlinks in the ZIP archives. This allows 7zip to unpack Android NDK archives
+			// without error.  The option appears to be undocumented, but was mentioned by the 7zip author here:
+			//
+			//   https://sourceforge.net/p/sevenzip/discussion/45798/thread/187ce54fb0/
+			//
+			if (version >= snldMinVersion) {
+				Log.DebugLine ("Adding option to ignore dangerous symlinks");
+				runner.AddArgument ("-snld");
+			}
+
 			// Disable progress indicator (doesn't appear to have any effect with some versions of 7z)
 			runner.AddArgument ("-bd");
 

build-tools/xaprepare/xaprepare/xaprepare.csproj

@@ -1,17 +1,16 @@
 <Project Sdk="Microsoft.NET.Sdk">
+  <Import Project="../../../Configuration.props" />
 
   <PropertyGroup>
     <TargetFramework>$(DotNetStableTargetFramework)</TargetFramework>
     <OutputType>Exe</OutputType>
-    <LangVersion>8.0</LangVersion>
+    <LangVersion>$(LangVersion)</LangVersion>
     <RootNamespace>Xamarin.Android.Prepare</RootNamespace>
     <AssemblyName>xaprepare</AssemblyName>
     <AllowUnsafeBlocks>true</AllowUnsafeBlocks>
     <Nullable>enable</Nullable>
   </PropertyGroup>
 
-  <Import Project="../../../Configuration.props" />
-
   <ItemGroup>
     <Compile Include="$(IntermediateOutputPath)/BuildInfo.Generated.cs" />
     <Compile Include="$(IntermediateOutputPath)/Properties.Defaults.cs" />