private object GetExpressionValue(ExpressionAst exprAst, bool isTrustedInput)
{
// be sure that there's a context at hand
if (_context == null)
{
var rs = RunspaceFactory.CreateRunspace(InitialSessionState.Create());
rs.Open();
_context = rs.ExecutionContext;
}
if (!isTrustedInput) // if it's not trusted, call the safe value visitor
{
return(GetSafeValueVisitor.GetSafeValue(exprAst, _context, GetSafeValueVisitor.SafeValueContext.GetPowerShell));
}
return(Compiler.GetExpressionValue(exprAst, isTrustedInput, _context, _usingValueMap));
}
private void ConvertCommand(CommandAst commandAst, bool isTrustedInput)
{
// First need command name.
var commandName = GetCommandName(commandAst.CommandElements[0], isTrustedInput);
var command = new Command(commandName, isScript: false, useLocalScope: _createLocalScope);
// Handle redirections, if any (there can really be just 0 or 1).
if (commandAst.Redirections.Count > 0)
{
Diagnostics.Assert(commandAst.Redirections.Count == 1, "only 1 kind of redirection is supported");
Diagnostics.Assert(commandAst.Redirections[0] is MergingRedirectionAst, "unexpected redirection type");
PipelineResultTypes toType = PipelineResultTypes.Output;
PipelineResultTypes fromType;
switch (commandAst.Redirections[0].FromStream)
{
case RedirectionStream.Error:
fromType = PipelineResultTypes.Error;
break;
case RedirectionStream.Warning:
fromType = PipelineResultTypes.Warning;
break;
case RedirectionStream.Verbose:
fromType = PipelineResultTypes.Verbose;
break;
case RedirectionStream.Debug:
fromType = PipelineResultTypes.Debug;
break;
case RedirectionStream.Information:
fromType = PipelineResultTypes.Information;
break;
case RedirectionStream.All:
fromType = PipelineResultTypes.All;
break;
default:
// Default to Error->Output to be compatible with V2.
fromType = PipelineResultTypes.Error;
break;
}
command.MergeMyResults(fromType, toType);
}
_powershell.AddCommand(command);
// Now the parameters and arguments.
foreach (var ast in commandAst.CommandElements.Skip(1))
{
var exprAst = ast as ExpressionAst;
if (exprAst != null)
{
VariableExpressionAst variableAst = null;
var usingExprAst = ast as UsingExpressionAst;
if (usingExprAst != null)
{
string usingAstKey = PsUtils.GetUsingExpressionKey(usingExprAst);
object usingValue = _usingValueMap[usingAstKey];
variableAst = usingExprAst.SubExpression as VariableExpressionAst;
if (variableAst != null && variableAst.Splatted)
{
// Support the splatting of a dictionary
var parameters = usingValue as System.Collections.IDictionary;
if (parameters != null)
{
_powershell.AddParameters(parameters);
}
else
{
// Support the splatting of an array
var arguments = usingValue as System.Collections.IEnumerable;
if (arguments != null)
{
foreach (object argument in arguments)
{
_powershell.AddArgument(argument);
}
}
else
{
// Splat the object directly.
_powershell.AddArgument(usingValue);
}
}
}
else
{
_powershell.AddArgument(usingValue);
}
continue;
}
variableAst = ast as VariableExpressionAst;
if (variableAst != null && variableAst.Splatted)
{
GetSplattedVariable(variableAst);
}
else
{
var constantExprAst = ast as ConstantExpressionAst;
object argument;
if (constantExprAst != null && LanguagePrimitives.IsNumeric(LanguagePrimitives.GetTypeCode(constantExprAst.StaticType)))
{
var commandArgumentText = constantExprAst.Extent.Text;
argument = constantExprAst.Value;
if (!commandArgumentText.Equals(constantExprAst.Value.ToString(), StringComparison.Ordinal))
{
// The wrapped number will actually return a PSObject which could end holding a reference to
// a typetable, making the object runspace specific. We should find a better way to avoid
// any possibility of sharing problems, though this is unlikely to cause problems.
argument = ParserOps.WrappedNumber(argument, commandArgumentText);
}
}
else
{
if (!isTrustedInput)
{
try
{
argument = GetSafeValueVisitor.GetSafeValue(exprAst, _context, GetSafeValueVisitor.SafeValueContext.GetPowerShell);
}
catch (System.Exception)
{
throw new ScriptBlockToPowerShellNotSupportedException(
"CantConvertWithDynamicExpression",
null,
AutomationExceptions.CantConvertWithDynamicExpression,
exprAst.Extent.Text);
}
}
else
{
argument = GetExpressionValue(exprAst, isTrustedInput);
}
}
_powershell.AddArgument(argument);
}
}
else
{
AddParameter((CommandParameterAst)ast, isTrustedInput);
}
}
}
// This method does parameter binding for a very limited set of scenarios, specifically
// for New-Alias, Set-Alias, Import-Module, and Export-ModuleMember. It might not even
// correctly handle these cmdlets if new parameters are added.
//
// It also only populates the bound parameters for a limited set of parameters needed
// for module analysis.
private Hashtable DoPsuedoParameterBinding(CommandAst commandAst, string commandName)
{
var result = new Hashtable(StringComparer.OrdinalIgnoreCase);
var parameterBindingInfo = s_parameterBindingInfoTable[commandName].parameterInfo;
int positionsBound = 0;
for (int i = 1; i < commandAst.CommandElements.Count; i++)
{
var element = commandAst.CommandElements[i];
var specifiedParameter = element as CommandParameterAst;
if (specifiedParameter != null)
{
bool boundParameter = false;
var specifiedParamName = specifiedParameter.ParameterName;
foreach (var parameterInfo in parameterBindingInfo)
{
if (parameterInfo.name.StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase))
{
if (parameterInfo.position != -1)
{
positionsBound |= 1 << parameterInfo.position;
}
var argumentAst = specifiedParameter.Argument;
if (argumentAst is null)
{
argumentAst = commandAst.CommandElements[i] as ExpressionAst;
if (argumentAst != null)
{
i += 1;
}
}
if (argumentAst != null)
{
boundParameter = true;
result[parameterInfo.name] =
GetSafeValueVisitor.GetSafeValue(argumentAst, null, GetSafeValueVisitor.SafeValueContext.ModuleAnalysis);
}
break;
}
}
if (boundParameter || specifiedParameter.Argument != null)
{
continue;
}
if (!"PassThru".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"Force".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"Confirm".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"Global".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"AsCustomObject".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"Verbose".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"Debug".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"DisableNameChecking".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase) &&
!"NoClobber".StartsWith(specifiedParamName, StringComparison.OrdinalIgnoreCase))
{
// Named parameter, skip the argument (except for specific switch parameters
i += 1;
}
}
else
{
// Positional argument, find which position we want to bind
int pos = 0;
for (; pos < 10; pos++)
{
if ((positionsBound & (1 << pos)) == 0)
{
break;
}
}
positionsBound |= 1 << pos;
// Now see if we care (we probably do, but if the user did something odd, like specify too many, then we don't really)
foreach (var parameterInfo in parameterBindingInfo)
{
if (parameterInfo.position == pos)
{
result[parameterInfo.name] = GetSafeValueVisitor.GetSafeValue(
commandAst.CommandElements[i], null,
GetSafeValueVisitor.SafeValueContext.ModuleAnalysis);
}
}
}
}
return(result);
}
// Visit one the other variations:
// - Dotting scripts
// - Setting aliases
// - Importing modules
// - Exporting module members
public override AstVisitAction VisitCommand(CommandAst commandAst)
{
string commandName =
commandAst.GetCommandName() ??
GetSafeValueVisitor.GetSafeValue(commandAst.CommandElements[0], null, GetSafeValueVisitor.SafeValueContext.ModuleAnalysis) as string;
if (commandName is null)
{
return(AstVisitAction.SkipChildren);
}
// They are trying to dot a script
if (commandAst.InvocationOperator == TokenKind.Dot)
{
// . Foo-Bar4.ps1
// . $psScriptRoot\Foo-Bar.ps1 -Bing Baz
// . ""$psScriptRoot\Support Files\Foo-Bar2.ps1"" -Bing Baz
// . '$psScriptRoot\Support Files\Foo-Bar3.ps1' -Bing Baz
DiscoveredModules.Add(
new RequiredModuleInfo {
Name = commandName, CommandsToPostFilter = new List <string>()
});
ModuleIntrinsics.Tracer.WriteLine("Module dots {0}", commandName);
}
// They are setting an alias.
if (string.Equals(commandName, "New-Alias", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "Microsoft.PowerShell.Utility\\New-Alias", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "Set-Alias", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "Microsoft.PowerShell.Utility\\Set-Alias", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "nal", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "sal", StringComparison.OrdinalIgnoreCase))
{
// Set-Alias Foo-Bar5 Foo-Bar
// Set-Alias -Name Foo-Bar6 -Value Foo-Bar
// sal Foo-Bar7 Foo-Bar
// sal -Value Foo-Bar -Name Foo-Bar8
var boundParameters = DoPsuedoParameterBinding(commandAst, commandName);
var name = boundParameters["Name"] as string;
if (!string.IsNullOrEmpty(name))
{
var value = boundParameters["Value"] as string;
if (!string.IsNullOrEmpty(value))
{
// These aren't stored in DiscoveredExports, as they are only
// exported after the user calls Export-ModuleMember.
DiscoveredAliases[name] = value;
ModuleIntrinsics.Tracer.WriteLine("Module defines alias: {0} = {1}", name, value);
}
}
return(AstVisitAction.SkipChildren);
}
// They are importing a module
if (string.Equals(commandName, "Import-Module", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "ipmo", StringComparison.OrdinalIgnoreCase))
{
// Import-Module Module1
// Import-Module Module2 -Function Foo-Module2*, Foo-Module2Second* -Cmdlet Foo-Module2Cmdlet,Foo-Module2Cmdlet*
// Import-Module Module3 -Function Foo-Module3Command1, Foo-Module3Command2
// Import-Module Module4,
// Module5
// Import-Module -Name Module6,
// Module7 -Global
var boundParameters = DoPsuedoParameterBinding(commandAst, commandName);
List <string> commandsToPostFilter = new List <string>();
Action <string> onEachCommand = importedCommandName =>
{
commandsToPostFilter.Add(importedCommandName);
};
// Process any exports from the module that we determine from
// the -Function, -Cmdlet, or -Alias parameters
ProcessCmdletArguments(boundParameters["Function"], onEachCommand);
ProcessCmdletArguments(boundParameters["Cmdlet"], onEachCommand);
ProcessCmdletArguments(boundParameters["Alias"], onEachCommand);
// Now, go through all of the discovered modules on Import-Module
// and register them for deeper investigation.
Action <string> onEachModule = moduleName =>
{
ModuleIntrinsics.Tracer.WriteLine("Discovered module import: {0}", moduleName);
DiscoveredModules.Add(
new RequiredModuleInfo
{
Name = moduleName,
CommandsToPostFilter = commandsToPostFilter
});
};
ProcessCmdletArguments(boundParameters["Name"], onEachModule);
return(AstVisitAction.SkipChildren);
}
// They are exporting a module member
if (string.Equals(commandName, "Export-ModuleMember", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "Microsoft.PowerShell.Core\\Export-ModuleMember", StringComparison.OrdinalIgnoreCase) ||
string.Equals(commandName, "$script:ExportModuleMember", StringComparison.OrdinalIgnoreCase))
{
// Export-ModuleMember *
// Export-ModuleMember Exported-UnNamedModuleMember
// Export-ModuleMember -Function Exported-FunctionModuleMember1, Exported-FunctionModuleMember2 -Cmdlet Exported-CmdletModuleMember `
// -Alias Exported-AliasModuleMember
// & $script:ExportModuleMember -Function (...)
var boundParameters = DoPsuedoParameterBinding(commandAst, commandName);
Action <string> onEachFunction = exportedCommandName =>
{
DiscoveredCommandFilters.Add(exportedCommandName);
ModuleIntrinsics.Tracer.WriteLine("Discovered explicit export: {0}", exportedCommandName);
// If the export doesn't contain wildcards, then add it to the
// discovered commands as well. It is likely that they created
// the command dynamically
if ((!WildcardPattern.ContainsWildcardCharacters(exportedCommandName)) &&
(!DiscoveredExports.Contains(exportedCommandName)))
{
DiscoveredExports.Add(exportedCommandName);
}
};
ProcessCmdletArguments(boundParameters["Function"], onEachFunction);
ProcessCmdletArguments(boundParameters["Cmdlet"], onEachFunction);
Action <string> onEachAlias = exportedAlias =>
{
DiscoveredCommandFilters.Add(exportedAlias);
// If the export doesn't contain wildcards, then add it to the
// discovered commands as well. It is likely that they created
// the command dynamically
if (!WildcardPattern.ContainsWildcardCharacters(exportedAlias))
{
DiscoveredAliases[exportedAlias] = null;
}
};
ProcessCmdletArguments(boundParameters["Alias"], onEachAlias);
return(AstVisitAction.SkipChildren);
}
// They are exporting a module member using our advanced 'public' function
// that we've presented in many demos
if ((string.Equals(commandName, "public", StringComparison.OrdinalIgnoreCase)) &&
(commandAst.CommandElements.Count > 2))
{
// public function Publicly-ExportedFunction
// public alias Publicly-ExportedAlias
string publicCommandName = commandAst.CommandElements[2].ToString().Trim();
DiscoveredExports.Add(publicCommandName);
DiscoveredCommandFilters.Add(publicCommandName);
}
return(AstVisitAction.SkipChildren);
}
