1 files changed, 141 insertions, 0 deletions
diff --git a/src/c-ares/test/ares-test-parse-mx.cc b/src/c-ares/test/ares-test-parse-mx.cc
new file mode 100644
index 000000000..37324a6d4
--- /dev/null
+++ b/src/c-ares/test/ares-test-parse-mx.cc
@@ -0,0 +1,141 @@
+#include "ares-test.h"
+#include "dns-proto.h"
+
+#include <sstream>
+#include <vector>
+
+namespace ares {
+namespace test {
+
+TEST_F(LibraryTest, ParseMxReplyOK) {
+  DNSPacket pkt;
+  pkt.set_qid(0x1234).set_response().set_aa()
+    .add_question(new DNSQuestion("example.com", ns_t_mx))
+    .add_answer(new DNSMxRR("example.com", 100, 100, "mx1.example.com"))
+    .add_answer(new DNSMxRR("example.com", 100, 200, "mx2.example.com"));
+  std::vector<byte> data = pkt.data();
+
+  struct ares_mx_reply* mx = nullptr;
+  EXPECT_EQ(ARES_SUCCESS, ares_parse_mx_reply(data.data(), data.size(), &mx));
+  ASSERT_NE(nullptr, mx);
+  EXPECT_EQ("mx1.example.com", std::string(mx->host));
+  EXPECT_EQ(100, mx->priority);
+
+  struct ares_mx_reply* mx2 = mx->next;
+  ASSERT_NE(nullptr, mx2);
+  EXPECT_EQ("mx2.example.com", std::string(mx2->host));
+  EXPECT_EQ(200, mx2->priority);
+  EXPECT_EQ(nullptr, mx2->next);
+
+  ares_free_data(mx);
+}
+
+TEST_F(LibraryTest, ParseMxReplyMalformed) {
+  std::vector<byte> data = {
+    0x12, 0x34,  // qid
+    0x84, // response + query + AA + not-TC + not-RD
+    0x00, // not-RA + not-Z + not-AD + not-CD + rc=NoError
+    0x00, 0x01,  // num questions
+    0x00, 0x01,  // num answer RRs
+    0x00, 0x00,  // num authority RRs
+    0x00, 0x00,  // num additional RRs
+    // Question
+    0x07, 'e', 'x', 'a', 'm', 'p', 'l', 'e',
+    0x03, 'c', 'o', 'm',
+    0x00,
+    0x00, 0x0F,  // type MX
+    0x00, 0x01,  // class IN
+    // Answer 1
+    0x07, 'e', 'x', 'a', 'm', 'p', 'l', 'e',
+    0x03, 'c', 'o', 'm',
+    0x00,
+    0x00, 0x0F,  // RR type
+    0x00, 0x01,  // class IN
+    0x01, 0x02, 0x03, 0x04, // TTL
+    0x00, 0x01,  // rdata length -- too short
+    0x02,
+  };
+
+  struct ares_mx_reply* mx = nullptr;
+  EXPECT_EQ(ARES_EBADRESP, ares_parse_mx_reply(data.data(), data.size(), &mx));
+  ASSERT_EQ(nullptr, mx);
+}
+
+
+TEST_F(LibraryTest, ParseMxReplyErrors) {
+  DNSPacket pkt;
+  pkt.set_qid(0x1234).set_response().set_aa()
+    .add_question(new DNSQuestion("example.com", ns_t_mx))
+    .add_answer(new DNSMxRR("example.com", 100, 100, "mx1.example.com"));
+  std::vector<byte> data;
+  struct ares_mx_reply* mx = nullptr;
+
+  // No question.
+  pkt.questions_.clear();
+  data = pkt.data();
+  EXPECT_EQ(ARES_EBADRESP, ares_parse_mx_reply(data.data(), data.size(), &mx));
+  EXPECT_EQ(nullptr, mx);
+  pkt.add_question(new DNSQuestion("example.com", ns_t_mx));
+
+#ifdef DISABLED
+  // Question != answer
+  pkt.questions_.clear();
+  pkt.add_question(new DNSQuestion("Axample.com", ns_t_mx));
+  data = pkt.data();
+  EXPECT_EQ(ARES_EBADRESP, ares_parse_mx_reply(data.data(), data.size(), &mx));
+  pkt.questions_.clear();
+  pkt.add_question(new DNSQuestion("example.com", ns_t_mx));
+#endif
+
+  // Two questions.
+  pkt.add_question(new DNSQuestion("example.com", ns_t_mx));
+  data = pkt.data();
+  EXPECT_EQ(ARES_EBADRESP, ares_parse_mx_reply(data.data(), data.size(), &mx));
+  EXPECT_EQ(nullptr, mx);
+  pkt.questions_.clear();
+  pkt.add_question(new DNSQuestion("example.com", ns_t_mx));
+
+  // Wrong sort of answer.
+  // TODO(drysdale): check if this should be ARES_ENODATA?
+  pkt.answers_.clear();
+  pkt.add_answer(new DNSSrvRR("example.abc.def.com", 180, 0, 10, 8160, "example.abc.def.com"));
+  data = pkt.data();
+  EXPECT_EQ(ARES_SUCCESS, ares_parse_mx_reply(data.data(), data.size(), &mx));
+  EXPECT_EQ(nullptr, mx);
+  pkt.answers_.clear();
+  pkt.add_answer(new DNSMxRR("example.com", 100, 100, "mx1.example.com"));
+
+  // No answer.
+  pkt.answers_.clear();
+  data = pkt.data();
+  EXPECT_EQ(ARES_ENODATA, ares_parse_mx_reply(data.data(), data.size(), &mx));
+  EXPECT_EQ(nullptr, mx);
+  pkt.add_answer(new DNSMxRR("example.com", 100, 100, "mx1.example.com"));
+
+  // Truncated packets.
+  data = pkt.data();
+  for (size_t len = 1; len < data.size(); len++) {
+    int rc = ares_parse_mx_reply(data.data(), len, &mx);
+    EXPECT_EQ(nullptr, mx);
+    EXPECT_TRUE(rc == ARES_EBADRESP || rc == ARES_EBADNAME);
+  }
+}
+
+TEST_F(LibraryTest, ParseMxReplyAllocFail) {
+  DNSPacket pkt;
+  pkt.set_qid(0x1234).set_response().set_aa()
+    .add_question(new DNSQuestion("example.com", ns_t_mx))
+    .add_answer(new DNSCnameRR("example.com", 300, "c.example.com"))
+    .add_answer(new DNSMxRR("c.example.com", 100, 100, "mx1.example.com"));
+  std::vector<byte> data = pkt.data();
+  struct ares_mx_reply* mx = nullptr;
+
+  for (int ii = 1; ii <= 5; ii++) {
+    ClearFails();
+    SetAllocFail(ii);
+    EXPECT_EQ(ARES_ENOMEM, ares_parse_mx_reply(data.data(), data.size(), &mx)) << ii;
+  }
+}
+
+}  // namespace test
+}  // namespace ares