return (toText(!isAbsolute()));
}
+void
+LabelSequence::extend(const LabelSequence& labels,
+ uint8_t buf[MAX_SERIALIZED_LENGTH])
+{
+ // check whether this labelsequence appears to have anything to do with
+ // the given buf at all
+ if (data_ != buf || offsets_ != &buf[Name::MAX_WIRE]) {
+ isc_throw(BadValue,
+ "extend() called with unrelated buffer");
+ }
+
+ // check name does not become too long
+ size_t orig_len = getDataLength() - 1;
+ if (orig_len + labels.getDataLength() > Name::MAX_WIRE) {
+ isc_throw(BadValue,
+ "extend() would exceed maximum wire length");
+ }
+
+ // check offsets data does not become too long
+ if (getLabelCount() + labels.getLabelCount() > Name::MAX_LABELS) {
+ isc_throw(BadValue,
+ "extend() would exceed maximum number of labels");
+ }
+
+ // append second to first labelsequence
+ size_t data_len;
+ const uint8_t *data = labels.getData(&data_len);
+ memcpy(buf + orig_len, data, data_len);
+
+ // append offsets
+ for (size_t i = 0; i < labels.getLabelCount(); ++i) {
+ buf[Name::MAX_WIRE + last_label_ + i] =
+ offsets_[last_label_] +
+ labels.offsets_[i + labels.first_label_] -
+ labels.offsets_[labels.first_label_];
+ }
+ last_label_ += labels.last_label_ - labels.first_label_;
+}
+
+
std::ostream&
operator<<(std::ostream& os, const LabelSequence& label_sequence) {
os << label_sequence.toText();
///
/// \note The given buf MUST remain in scope during the lifetime of
/// the LabelSequence created here.
+ /// \note The buffer should never be modified except through
+ /// calls to extend().
+ /// \note Also, only associate the buffer with at most one
+ /// LabelSequence. Behaviour is undefined if two LabelSequences are
+ /// using the same buffer.
///
/// \param src LabelSequence to copy the initial data from
/// \param buf external buffer to store this labelsequence's data in
/// \return a string representation of the <code>LabelSequence</code>.
std::string toText() const;
+ /// \brief Extend this LabelSequence with the given labelsequence
+ ///
+ /// The given labels are added to the name data, and internal data
+ /// is updated accordingly.
+ /// The data from the given LabelSequence is copied into the buffer
+ /// associated with this LabelSequence; the appended LabelSequence
+ /// can be released if it is not needed for other operations anymore.
+ ///
+ /// Some minimal checking is done on the data, but internal integrity
+ /// is not assumed. Do NOT modify the given buffer except through calls
+ /// to this method, and do NOT call this method if the buffer is
+ /// associated to another LabelSequence (behaviour of the other
+ /// LabelSequence is undefined in that scenario).
+ ///
+ /// \exception BadValue If the buffer does not appear to be associated
+ /// with this LabelSequence, or if the maximum wire length or maximum
+ /// number of labels would be exceeded by this operation
+ ///
+ /// \param labels The labels to append to this LabelSequence
+ /// \param buf The buffer associated with this LabelSequence
+ void extend(const LabelSequence& labels,
+ uint8_t buf[MAX_SERIALIZED_LENGTH]);
+
private:
/// \brief Convert the LabelSequence to a string.
///
}
}
+// Check some basic 'extend' functionality
+TEST(LabelSequence, extend) {
+ Name n1("foo.bar.");
+ Name n2("foo");
+ Name n3("bar");
+ LabelSequence ls1(n1);
+ LabelSequence ls2(n2);
+ LabelSequence ls3(n3);
+ LabelSequence ls4(n1);
+
+ uint8_t buf[LabelSequence::MAX_SERIALIZED_LENGTH];
+ memset(buf, 0, LabelSequence::MAX_SERIALIZED_LENGTH);
+ LabelSequence els(ls2, buf);
+
+ check_compare(ls1, els, isc::dns::NameComparisonResult::COMMONANCESTOR, 1);
+ els.extend(ls3, buf);
+
+ check_compare(ls1, els, isc::dns::NameComparisonResult::EQUAL, 3);
+ stripLeftCheck(ls1, els, ls4);
+ stripRightCheck(ls1, els, ls4);
+
+ els.extend(ls3, buf);
+ check_compare(ls1, ls2, isc::dns::NameComparisonResult::COMMONANCESTOR, 1);
+}
+
+// Check that when extending with itself, it does not cause horrible failures
+TEST(LabelSequence, extendWithItself) {
+ Name n1("foo.bar.");
+ Name n2("foo.bar.foo.bar.");
+ LabelSequence ls1(n1);
+ LabelSequence ls2(n2);
+
+ uint8_t buf[LabelSequence::MAX_SERIALIZED_LENGTH];
+ memset(buf, 0, LabelSequence::MAX_SERIALIZED_LENGTH);
+ LabelSequence els(ls1, buf);
+
+ std::cout << "[XX] " << els.toText() << std::endl;
+ // some men just want to watch the world burn.
+ els.extend(els, buf);
+ std::cout << "[XX] " << els.toText() << std::endl;
+ check_equal(ls2, els);
+}
+
+// Test that 'extending' with just a root label is a no-op
+TEST(LabelSequence, extendWithRoot) {
+ Name n1("example.org");
+ LabelSequence ls1(n1);
+ uint8_t buf[LabelSequence::MAX_SERIALIZED_LENGTH];
+ LabelSequence els(LabelSequence(ls1, buf));
+ check_equal(ls1, els);
+ els.extend(LabelSequence(Name(".")), buf);
+ check_equal(ls1, els);
+}
+
+// Check possible failure modes of extend()
+TEST(LabelSequence, extendBadData) {
+ Name n1("example.org.");
+ LabelSequence ls1(n1);
+
+ uint8_t buf[LabelSequence::MAX_SERIALIZED_LENGTH];
+ memset(buf, 0, LabelSequence::MAX_SERIALIZED_LENGTH);
+ LabelSequence els(ls1, buf);
+
+ // try use with unrelated labelsequence
+ EXPECT_THROW(ls1.extend(ls1, buf), isc::BadValue);
+
+ // Create a long name, but so that we can still extend once
+ Name longlabel("1234567890123456789012345678901234567890"
+ "12345678901234567890");
+ LabelSequence ls2(longlabel);
+ els = LabelSequence(ls2, buf);
+ els.extend(els, buf);
+ els.extend(ls2, buf);
+ els.extend(ls2, buf);
+ ASSERT_EQ(245, els.getDataLength());
+ // Extending once more with 10 bytes should still work
+ els.extend(LabelSequence(Name("123456789")), buf);
+ // But now, even the shortest extension should fail
+ EXPECT_THROW(els.extend(LabelSequence(Name("1")), buf), isc::BadValue);
+
+ // Also check that extending past MAX_LABELS is not possible
+ Name shortname("1.");
+ LabelSequence short_ls(shortname);
+ els = LabelSequence(short_ls, buf);
+ for (size_t i=0; i < 125; ++i) {
+ els.extend(short_ls, buf);
+ }
+ EXPECT_THROW(els.extend(short_ls, buf), isc::BadValue);
+}
}
projects / thirdparty / kea.git / commitdiff
