protected string ResolveXPathFunctionArgVariables(string arg, AlpheusXsltContext context)
{
CallerInformation here = this.AuditEnvironment.Here();
Match m = Regex.Match(arg, @"\%\((\S+)\:(\S+)\)");
if (m.Success)
{
string p = m.Groups[1].Value;
string n = m.Groups[2].Value;
object v = EvaluateXPathVariable(new AlpheusXPathVariable(p, n), context);
if (v is string || v is bool || v is double)
{
Debug("Resolving XPath variable reference ${0}:{1} in arg {2} to {3}.", p, n, arg, (string)v);
return(arg.Replace(m.Groups[0].Value, (string)v));
}
else
{
Error("Variable ${0}:{1} is not a value type.", p, n);
return(arg);
}
}
else
{
return(arg);
}
}
public override object EvaluateXPathVariable(AlpheusXPathVariable v, AlpheusXsltContext xslt_context)
{
switch (v.Prefix)
{
case "os":
switch (v.Name)
{
case "platform":
if (this.AuditEnvironment.IsWindows)
{
return("Windows");
}
else
{
return("Unix");
}
default:
this.AuditEnvironment.Error("Unknown os variable: {0}", v.Name);
return(string.Empty);
}
case "env":
return(this.AuditEnvironment.GetEnvironmentVar((string)v.Name));
case "fs":
if (v.Name.StartsWith("_"))
{
Debug("Function store reference fs:{0} not initialised yet.", v.Name);
}
else
{
this.AuditEnvironment.Error("Unknown fs variable: {1}", v.Name);
}
return(string.Empty);
case "app":
if (this.AuditTarget.AuditOptions.ContainsKey(v.Name))
{
string o = (string)this.AuditTarget.AuditOptions[v.Name];
string values = o.Split(';').Select(value => "<value>" + value + "</value>").Aggregate((v1, v2) => v1 + v2);
return(XElement.Parse(values).CreateNavigator());
}
else
{
this.AuditEnvironment.Error("Unknown audit option: {0}:{1}", v.Prefix, v.Name);
return(null);
}
case "appfs":
if (this.Application.ApplicationFileSystemMap.ContainsKey(v.Name))
{
AuditFileSystemInfo f = this.Application.ApplicationFileSystemMap[v.Name];
Debug("Resolved appfs:{0} variable to {1}.", v.Name, f.FullName);
return(f.FullName);
}
else
{
Error("appfs:{0} does not exist in the application file system map.", v.Name);
return(string.Empty);
}
default:
this.AuditEnvironment.Error("Unknown variable type: {0}:{1}", v.Prefix, v.Name);
return(string.Empty);
}
}
public override object InvokeXPathFunction(AlpheusXPathFunction f, AlpheusXsltContext xslt_context, object[] args, XPathNavigator doc_context)
{
for (int argc = 0; argc < args.Length; argc++)
{
if (args[argc] is string)
{
args[argc] = ResolveXPathFunctionArgVariables((string)args[argc], xslt_context);
}
}
switch (f.Prefix)
{
case "l":
switch (f.Name)
{
case "any":
string e;
XPathNodeIterator iter = (args[0] as XPathNodeIterator).Clone();
if (args.Count() == 1)
{
e = "./";
}
else
{
e = (string)args[1];
}
XPathExpression expr = this.CompileXPathExpression(e, doc_context);
if (expr == null)
{
Error("Failed to execute l:any with expression {0}.", e);
return(false);
}
object r;
while (iter.MoveNext())
{
r = iter.Current.Evaluate(expr);
if (r == null)
{
continue;
}
else if (r as bool? != null)
{
bool?b = r as bool?;
if (b.HasValue && b.Value)
{
return(true);
}
}
else if (r is XPathNodeIterator)
{
XPathNodeIterator i = r as XPathNodeIterator;
if (i.Count > 0)
{
return(true);
}
}
else if (r is double?)
{
double?d = r as double?;
if (d.HasValue)
{
return(true);
}
}
else if (r is string)
{
string s = (string)r;
if (!string.IsNullOrEmpty(s))
{
return(true);
}
}
else
{
throw new Exception("Unknown result type from evaluating expression " + e + " at iterator position " + iter.CurrentPosition);
}
}
return(f);
default:
throw new NotImplementedException("The XPath function " + f.Prefix + ":" + f.Name + " is not implemented.");
}
case "db":
switch (f.Name)
{
case "query":
if (this.AuditTarget is IDbAuditTarget)
{
IDbAuditTarget db = this.AuditTarget as IDbAuditTarget;
return(db.ExecuteDbQueryToXml(args));
}
else
{
this.AuditEnvironment.Error("The current target is not a database server or application and does not support queries.");
XmlDocument doc = new XmlDocument();
doc.LoadXml("<error>No Database</error>");
return(doc.CreateNavigator().Select("/"));
}
default:
throw new NotImplementedException("The XPath function " + f.Prefix + ":" + f.Name + " is not supported by IDbAuditTarget.");
}
case "os":
switch (f.Name)
{
case "exec":
string output = string.Empty, command = "", arguments = "";
if (args.Count() == 1)
{
command = (string)args[0];
}
else
{
command = (string)args[0];
arguments = (string)args[1];
}
output = this.AuditEnvironment.OSExec(command, arguments);
this.AuditEnvironment.Debug("os:exec {0} {1} returned {2}.", command, arguments, string.IsNullOrEmpty(output) ? "null" : output);
return(output);
default:
throw new NotImplementedException("The XPath function " + f.Prefix + ":" + f.Name + " is not supported by this audit target.");
}
case "fs":
switch (f.Name)
{
case "unix-file-mode":
return(this.AuditEnvironment.GetUnixFileMode((string)args[0]));
case "find-files":
return(this.AuditEnvironment.FindFiles((string)args[0], (string)args[1]));
case "find-dirs":
return(this.AuditEnvironment.FindDirectories((string)args[0], (string)args[1]));
case "is-symbolic-link":
return(this.AuditEnvironment.GetIsSymbolicLink((string)args[0]));
case "symbolic-link-location":
return(this.AuditEnvironment.GetSymbolicLinkLocation((string)args[0]));
default:
throw new NotImplementedException("The XPath function " + f.Prefix + ":" + f.Name + " is not supported by any audit target.");
}
case "ver":
string version = (string)args[0];
switch (f.Name)
{
case "lt":
return(this.Application.IsVulnerabilityVersionInPackageVersionRange("<" + version, this.Application.Version));
case "gt":
return(this.Application.IsVulnerabilityVersionInPackageVersionRange(">" + version, this.Application.Version));
case "eq":
return(this.Application.IsVulnerabilityVersionInPackageVersionRange(version, this.Application.Version));
case "lte":
return(this.Application.IsVulnerabilityVersionInPackageVersionRange("<=" + version, this.Application.Version));
case "gte":
return(this.Application.IsVulnerabilityVersionInPackageVersionRange(">=" + version, this.Application.Version));
default:
throw new NotImplementedException("The XPath function " + f.Prefix + ":" + f.Name + " is not supported by any audit target.");
}
default:
throw new NotImplementedException("The XPath function prefix" + f.Prefix + " is not supported by any audit targets.");
}
}