Add propagation to String strip methods (reverted)

dd-java-agent/agent-iast/src/main/java/com/datadog/iast/propagation/StringModuleImpl.java

@@ -567,6 +567,43 @@ public void onSplit(@Nonnull String self, @Nonnull String[] result) {
     }
   }
 
+  @Override
+  @SuppressFBWarnings("ES_COMPARING_PARAMETER_STRING_WITH_EQ")
+  public void onStringStrip(@Nonnull String self, @Nonnull String result, boolean trailing) {
+    if (self == result || !canBeTainted(result)) {
+      return;
+    }
+    final IastContext ctx = IastContext.Provider.get();
+    if (ctx == null) {
+      return;
+    }
+    final TaintedObjects taintedObjects = ctx.getTaintedObjects();
+    final TaintedObject taintedSelf = taintedObjects.get(self);
+    if (taintedSelf == null) {
+      return;
+    }
+
+    final Range[] rangesSelf = taintedSelf.getRanges();
+    if (rangesSelf.length == 0) {
+      return;
+    }
+
+    int offset = 0;
+    if (!trailing) {
+      while ((offset < self.length()) && (Character.isWhitespace(self.charAt(offset)))) {
+        offset++;
+      }
+    }
+
+    int resultLength = result.length();
+
+    final Range[] newRanges = Ranges.forSubstring(offset, resultLength, rangesSelf);
+
+    if (newRanges != null) {
+      taintedObjects.taint(result, newRanges);
+    }
+  }
+
   /**
    * Adds the tainted ranges belonging to the current parameter added via placeholder taking care of
    * an optional tainted placeholder.

dd-java-agent/agent-iast/src/test/groovy/com/datadog/iast/propagation/StringModuleTest.groovy

@@ -984,6 +984,62 @@ class StringModuleTest extends IastModuleImplTestBase {
     '==>testing<== the ==>test<==' | ' '    | ['==>testing<==', '==>the<==', '==>test<=='] as String[]
   }
 
+  void 'test #method and make sure IastRequestContext is called'() {
+    given:
+    final taintedObjects = ctx.getTaintedObjects()
+    def self = addFromTaintFormat(taintedObjects, testString)
+    def result = self."$method"()
+
+    when:
+    module.onStringStrip(self, result, trailing)
+    def taintedObject = taintedObjects.get(result)
+
+    then:
+    1 * tracer.activeSpan() >> span
+    taintFormat(result, taintedObject.getRanges()) == expected
+
+    where:
+    method          | trailing | testString                                                      | expected
+    "strip"         | false    | "   ==>123<==   "                                               | "==>123<=="
+    "stripLeading"  | false    | "   ==>123<==   "                                               | "==>123<==   "
+    "stripTrailing" | true     | "   ==>123<==   "                                               | "   ==>123<=="
+    "strip"         | false    | " ==>   <== ==>   <== ==>456<== ==>ABC<== ==>   <== ==>   <== " | "==>456<== ==>ABC<=="
+    "stripLeading"  | false    | " ==>   <== ==>   <== ==>456<== ==>ABC<== ==>   <== ==>   <== " | "==>456<== ==>ABC<== ==>   <== ==>   <== "
+    "stripTrailing" | true     | " ==>   <== ==>   <== ==>456<== ==>ABC<== ==>   <== ==>   <== " | " ==>   <== ==>   <== ==>456<== ==>ABC<=="
+    "strip"         | false    | "   ==>123<==   "                                               | "==>123<=="
+    "stripLeading"  | false    | "   ==>123<==   "                                               | "==>123<==   "
+    "stripTrailing" | true     | "   ==>123<==   "                                               | "   ==>123<=="
+    "strip"         | false    | "==>   123   <=="                                               | "==>123<=="
+    "stripLeading"  | false    | "==>   123   <=="                                               | "==>123   <=="
+    "stripTrailing" | true     | "==>   123   <=="                                               | "==>   123<=="
+    "strip"         | false    | "   a==> b <==c   "                                             | "a==> b <==c"
+    "stripLeading"  | false    | "   a==> b <==c   "                                             | "a==> b <==c   "
+    "stripTrailing" | true     | "   a==> b <==c   "                                             | "   a==> b <==c"
+  }
+
+  void 'test #method for empty string cases'() {
+    given:
+    final taintedObjects = ctx.getTaintedObjects()
+    def self = addFromTaintFormat(taintedObjects, testString)
+    def result = self."$method"()
+
+    when:
+    module.onStringStrip(self, result, trailing)
+
+    then:
+    null == taintedObjects.get(result)
+    result == expected
+
+    where:
+    method          | trailing | testString              | expected
+    "strip"         | false    | " ==>   <== "           | ""
+    "stripLeading"  | false    | " ==>   <== "           | ""
+    "stripTrailing" | true     | " ==>   <== "           | ""
+    "strip"         | false    | ""                      | ""
+    "stripLeading"  | false    | ""                      | ""
+    "stripTrailing" | true     | ""                      | ""
+  }
+
   private static Date date(final String pattern, final String value) {
     return new SimpleDateFormat(pattern).parse(value)
   }

dd-java-agent/instrumentation/java-lang/java-lang-11/src/main/java/datadog/trace/instrumentation/java/lang/jdk11/StringCallSite.java

@@ -26,4 +26,33 @@ public static String afterRepeat(
     }
     return result;
   }
+
+  @CallSite.After("java.lang.String java.lang.String.strip()")
+  @CallSite.After("java.lang.String java.lang.String.stripLeading()")
+  public static String afterStrip(
+      @CallSite.This final String self, @CallSite.Return final String result) {
+    final StringModule module = InstrumentationBridge.STRING;
+    try {
+      if (module != null) {
+        module.onStringStrip(self, result, false);
+      }
+    } catch (final Throwable e) {
+      module.onUnexpectedException("afterStrip threw", e);
+    }
+    return result;
+  }
+
+  @CallSite.After("java.lang.String java.lang.String.stripTrailing()")
+  public static String afterStripTrailing(
+      @CallSite.This final String self, @CallSite.Return final String result) {
+    final StringModule module = InstrumentationBridge.STRING;
+    try {
+      if (module != null) {
+        module.onStringStrip(self, result, true);
+      }
+    } catch (final Throwable e) {
+      module.onUnexpectedException("afterStripTrailing threw", e);
+    }
+    return result;
+  }
 }

dd-java-agent/instrumentation/java-lang/java-lang-11/src/test/groovy/datadog/trace/instrumentation/java/lang/jdk11/StringCallSiteTest.groovy

@@ -1,3 +1,5 @@
+package datadog.trace.instrumentation.java.lang.jdk11
+
 import datadog.trace.agent.test.AgentTestRunner
 import datadog.trace.api.iast.InstrumentationBridge
 import datadog.trace.api.iast.propagation.StringModule
@@ -31,4 +33,23 @@ class StringCallSiteTest extends AgentTestRunner {
     1 * iastModule.onStringRepeat(self, count, expected)
     0 * _
   }
+
+  def 'test string #method call site'() {
+    setup:
+    final module = Mock(StringModule)
+    InstrumentationBridge.registerIastModule(module)
+
+    when:
+    final result = TestStringJDK11Suite."$method"(input)
+
+    then:
+    result == output
+    1 * module.onStringStrip(input, output, trailing)
+
+    where:
+    method                | trailing | input     | output
+    "stringStrip"         | false    | ' hello ' | 'hello'
+    "stringStripLeading"  | false    | ' hello ' | 'hello '
+    "stringStripTrailing" | true     | ' hello ' | ' hello'
+  }
 }

dd-java-agent/instrumentation/java-lang/java-lang-11/src/test/java/foo/bar/TestStringJDK11Suite.java

@@ -15,4 +15,25 @@ public static String stringRepeat(String self, int count) {
     LOGGER.debug("After string repeat {}", result);
     return result;
   }
+
+  public static String stringStrip(final String self) {
+    LOGGER.debug("Before string strip {}", self);
+    final String result = self.strip();
+    LOGGER.debug("After string strip {}", result);
+    return result;
+  }
+
+  public static String stringStripLeading(final String self) {
+    LOGGER.debug("Before string stripLeading {}", self);
+    final String result = self.stripLeading();
+    LOGGER.debug("After string stripLeading {}", result);
+    return result;
+  }
+
+  public static String stringStripTrailing(final String self) {
+    LOGGER.debug("Before string stripTrailing {}", self);
+    final String result = self.stripTrailing();
+    LOGGER.debug("After string stripTrailing {}", result);
+    return result;
+  }
 }

internal-api/src/main/java/datadog/trace/api/iast/propagation/StringModule.java

@@ -50,4 +50,6 @@ void onStringFormat(
       @Nonnull Iterable<String> literals, @Nonnull Object[] params, @Nonnull String result);
 
   void onSplit(final @Nonnull String self, final @Nonnull String[] result);
+
+  void onStringStrip(@Nonnull String self, @Nonnull String result, boolean trailing);
 }