/// <summary>
/// Initializes a new instance of the <see cref="RuleContext"/> class.
/// </summary>
/// <param name="index">The index.</param>
/// <param name="ruleSetContext">The rule set context.</param>
/// <param name="currentContent"></param>
/// <param name="rule">The rule.</param>
public RuleContext(int index, RuleSetContext ruleSetContext, byte[] currentContent, IRule rule)
: base(ruleSetContext)
{
if (currentContent == null)
{
throw new ArgumentNullException("currentContent");
}
if (rule == null)
{
throw new ArgumentNullException("rule");
}
RuleIndex = index;
LogCategory = "Rule " + index;
_currentContent = currentContent;
_substitutedContent = currentContent;
CurrentUrl = ruleSetContext.RequestedUrl;
_substitutedUrl = ruleSetContext.RequestedUrl;
CurrentRule = rule;
}
/// <summary>
/// Gets the value.
/// </summary>
/// <param name="context">The context.</param>
/// <returns></returns>
public string GetValue(string input, RuleSetContext context)
{
// if the value has already been cached then return that value instead of reprocessing
if (Value != null)
{
return Value;
}
var value = String.Empty;
if ((_type & ServerVariableType.ServerVariables) != 0)
{
value = context.HttpContext.Request.ServerVariables[_name];
// check to see if the value was found if not try the switch statement
if (string.IsNullOrEmpty(value))
{
switch (_name)
{
case "TIME_YEAR":
value = DateTime.Today.Year.ToString();
break;
case "TIME_MON":
value = DateTime.Today.Month.ToString();
break;
case "TIME_DAY":
value = DateTime.Today.Day.ToString();
break;
case "TIME_HOUR":
value = DateTime.Now.Hour.ToString();
break;
case "TIME_MIN":
value = DateTime.Now.Minute.ToString();
break;
case "TIME_SEC":
value = DateTime.Now.Second.ToString();
break;
case "TIME_WDAY":
value = DateTime.Today.DayOfWeek.ToString();
break;
case "TIME":
value = DateTime.Now.ToString("f");
break;
case "API_VERSION":
value = String.Empty;
break;// TODO: figure out how to attack this
case "THE_REQUEST":
value = context.HttpContext.Request.ServerVariables["REQUEST_METHOD"] + " " + context.HttpContext.Request.ServerVariables["PATH_INFO"] + " " + context.HttpContext.Request.ServerVariables["SERVER_PROTOCOL"];
break;
case "REQUEST_URI":
value = context.HttpContext.Request.ServerVariables["URL"];
break;
case "REQUEST_FILENAME":
value = context.HttpContext.Request.ServerVariables["PATH_TRANSLATED"];
break;
case "IS_SUBREQ":
value = String.IsNullOrEmpty(context.HttpContext.Request.Headers["X-Rewriter-Transfer"]) ? Boolean.FalseString : Boolean.TrueString;
break;
}
}
}
else if ((_type & ServerVariableType.Headers) != 0)
{
value = context.HttpContext.Request.Headers[_name];
}
else if ((_type & ServerVariableType.QueryString) != 0)
{
value = context.HttpContext.Request.QueryString[_name];
}
else if ((_type & ServerVariableType.Form) != 0)
{
value = context.HttpContext.Request.Form[_name];
}
else if ((_type & ServerVariableType.Cookies) != 0)
{
var cookie = context.HttpContext.Request.Cookies[_name];
// if cookie was found set the value to the value of the cookie
if (cookie != null)
{
value = cookie.Value;
}
}
Logger.InfoFormat("Input: " + value);
Value = value;
return value;
}
/// <summary>
/// Runs the rules.
/// </summary>
/// <param name="httpContext">The HTTP context.</param>
/// <param name="url">The URL.</param>
/// <returns>
/// Returns a rewritten <see cref="System.Uri"/>, or a value of <see langword="null"/> if no rewriting was done to <paramref name="url"/>.
/// </returns>
public Uri RunRules(HttpContextBase httpContext, Uri url)
{
var context = new RuleSetContext(this, url, httpContext);
var currentUrl = url;
if (!EngineEnabled)
{
Logger.Info("Rewrite Engine Is DISABLED");
}
if (_rules.Count > 0 && EngineEnabled)
{
Logger.InfoFormat("Input: " + currentUrl);
// check if max number of internal transfers have been exceeded
if (InternalTransferCount(httpContext) > MaxInternalTransfers)
{
string message = "Exceeded the max number of internal transfers.";
throw new HttpException(500, message);
}
IRuleFlagProcessor temporyFlags = null;
var skipNextChain = false;
var initialUrl = currentUrl;
if (!string.IsNullOrEmpty(VirtualBase) && VirtualBase != "/")
{
currentUrl = RemoveBase(VirtualBase, currentUrl);
}
// process rules according to their settings
for (var i = 0; i < _rules.Count; i++)
{
var ruleContext = new RuleContext(i, context, currentUrl, _rules[i]);
temporyFlags = _rules[i].Flags;
// continue if this rule shouldn't be processed because it doesn't allow internal transfer requests
if (RuleFlagsProcessor.HasNotForInternalSubRequests(temporyFlags) && IsInternalTransfer(httpContext))
{
continue;
}
var containsChain = RuleFlagsProcessor.HasChain(_rules[i].Flags);
var previousContainsChain = RuleFlagsProcessor.HasChain(_rules[Math.Max(0, i - 1)].Flags);
// if the previous rule doesn't contain a chain flag then set the initial URL
// this will be used to reset a chain if one of the chain rules fail
if (!previousContainsChain)
{
initialUrl = currentUrl;
}
// skip if the current rule or the last rule has a chain flag
// and if the skip next chain is set
if (skipNextChain && (previousContainsChain || containsChain))
{
continue;
}
else
{
skipNextChain = false;
}
if (_rules[i].TryExecute(ruleContext))
{
var flagResponse = temporyFlags.Apply(ruleContext);
currentUrl = ruleContext.SubstitutedUrl;
i = ruleContext.RuleIndex ?? -1;
var breakLoop = false;
// apply the flags to the rules, and only do special processing
// for the flag responses listed in the switch statement below
switch (flagResponse)
{
case RuleFlagProcessorResponse.ExitRuleSet:
return null;
case RuleFlagProcessorResponse.LastRule:
breakLoop = true;
break;
}
// break the loop because we have reached the last rule as indicated by a flag
if (breakLoop)
{
break;
}
}
else if (containsChain)
{
skipNextChain = true;
// reset the current URL back to the initial URL from the start of the chain
currentUrl = initialUrl;
}
else if (previousContainsChain)
{
// reset the current URL back to the initial URL from the start of the chain
currentUrl = initialUrl;
}
}
if (!string.IsNullOrEmpty(VirtualBase) && VirtualBase != "/")
{
currentUrl = AddBase(VirtualBase, currentUrl);
}
Logger.InfoFormat("Output: {0}", currentUrl);
}
// if the http request url matches for both the request and the rewrite no work was done so the url should be null
if (Uri.Compare(currentUrl, url, UriComponents.HttpRequestUrl, UriFormat.SafeUnescaped, StringComparison.OrdinalIgnoreCase) == 0)
{
currentUrl = null;
}
return currentUrl;
}
/// <summary>
/// Initializes a new instance of the <see cref="RuleSetContext"/> class.
/// </summary>
/// <param name="copy">The copy.</param>
internal RuleSetContext(RuleSetContext copy)
{
if (copy == null)
{
throw new ArgumentNullException("copy");
}
RuleSet = copy.RuleSet;
RequestedUrl = copy.RequestedUrl;
_responseContent = copy._responseContent;
HttpContext = copy.HttpContext;
IsOutputRuleSet = copy.IsOutputRuleSet;
LogCategory = String.Empty;
}
/// <summary>
///
/// </summary>
/// <param name="httpContext"></param>
/// <param name="content"></param>
/// <returns></returns>
public byte[] RunOutputRules(HttpContextBase httpContext, byte[] content)
{
var context = new RuleSetContext(this, content, httpContext);
var currentContent = content;
if (!EngineEnabled)
{
Logger.Info("Rewrite Engine Is DISABLED");
}
if (_outputRules.Count > 0 && EngineEnabled)
{
IRuleFlagProcessor temporyFlags = null;
var skipNextChain = false;
var initialContent = currentContent;
// process rules according to their settings
for (var i = 0; i < _outputRules.Count; i++)
{
var ruleContext = new RuleContext(i, context, currentContent, _outputRules[i]);
temporyFlags = _outputRules[i].Flags;
var containsChain = RuleFlagsProcessor.HasChain(_outputRules[i].Flags);
var previousContainsChain = RuleFlagsProcessor.HasChain(_outputRules[Math.Max(0, i - 1)].Flags);
// if the previous rule doesn't contain a chain flag then set the initial URL
// this will be used to reset a chain if one of the chain rules fail
if (!previousContainsChain)
{
initialContent = currentContent;
}
// skip if the current rule or the last rule has a chain flag
// and if the skip next chain is set
if (skipNextChain && (previousContainsChain || containsChain))
{
continue;
}
else
{
skipNextChain = false;
}
if (_outputRules[i].TryExecute(ruleContext))
{
var flagResponse = temporyFlags.Apply(ruleContext);
currentContent = ruleContext.SubstitutedContent;
i = ruleContext.RuleIndex ?? -1;
var breakLoop = false;
// apply the flags to the rules, and only do special processing
// for the flag responses listed in the switch statement below
switch (flagResponse)
{
case RuleFlagProcessorResponse.ExitRuleSet:
return null;
case RuleFlagProcessorResponse.LastRule:
breakLoop = true;
break;
}
// break the loop because we have reached the last rule as indicated by a flag
if (breakLoop)
{
break;
}
}
else if (containsChain)
{
skipNextChain = true;
// reset the current URL back to the initial URL from the start of the chain
currentContent = initialContent;
}
else if (previousContainsChain)
{
// reset the current URL back to the initial URL from the start of the chain
currentContent = initialContent;
}
}
}
return currentContent;
}
