[fuzz] Fix bugs in HPACK fuzz test

test/common/http/http2/hpack_fuzz_test.cc

@@ -8,6 +8,7 @@
 #include "test/test_common/utility.h"
 
 #include "absl/container/fixed_array.h"
+#include "absl/strings/escaping.h"
 #include "nghttp2/nghttp2.h"
 
 namespace Envoy {
@@ -25,6 +26,8 @@ std::vector<nghttp2_nv> createNameValueArray(const test::fuzz::Headers& input) {
   for (const auto& header : input.headers()) {
     // TODO(asraa): Consider adding flags in fuzzed input.
     const uint8_t flags = 0;
+    ENVOY_LOG_MISC(trace, "encoding: {} {}", absl::CEscape(header.key()),
+                   absl::CEscape(header.value()));
     nva[i++] = {const_cast<uint8_t*>(reinterpret_cast<const uint8_t*>(header.key().data())),
                 const_cast<uint8_t*>(reinterpret_cast<const uint8_t*>(header.value().data())),
                 header.key().size(), header.value().size(), flags};
@@ -56,18 +59,18 @@ Buffer::OwnedImpl encodeHeaders(nghttp2_hd_deflater* deflater,
   return payload;
 }
 
-std::vector<nghttp2_nv> decodeHeaders(nghttp2_hd_inflater* inflater,
-                                      const Buffer::OwnedImpl& payload, bool end_headers) {
+std::vector<std::pair<std::string, std::string>>
+decodeHeaders(nghttp2_hd_inflater* inflater, const Buffer::OwnedImpl& payload, bool end_headers) {
   // Decode using nghttp2
   Buffer::RawSliceVector slices = payload.getRawSlices();
   const int num_slices = slices.size();
   ASSERT(num_slices == 1, absl::StrCat("number of slices ", num_slices));
 
-  std::vector<nghttp2_nv> decoded_headers;
+  std::vector<std::pair<std::string, std::string>> decoded_headers;
   int inflate_flags = 0;
-  nghttp2_nv decoded_nv;
+  nghttp2_nv nv;
   while (slices[0].len_ > 0) {
-    ssize_t result = nghttp2_hd_inflate_hd2(inflater, &decoded_nv, &inflate_flags,
+    ssize_t result = nghttp2_hd_inflate_hd2(inflater, &nv, &inflate_flags,
                                             reinterpret_cast<uint8_t*>(slices[0].mem_),
                                             slices[0].len_, end_headers);
     // Decoding should not fail and data should not be left in slice.
@@ -78,7 +81,10 @@ std::vector<nghttp2_nv> decodeHeaders(nghttp2_hd_inflater* inflater,
 
     if (inflate_flags & NGHTTP2_HD_INFLATE_EMIT) {
       // One header key value pair has been successfully decoded.
-      decoded_headers.push_back(decoded_nv);
+      decoded_headers.push_back({std::string(reinterpret_cast<char*>(nv.name), nv.namelen),
+                                 std::string(reinterpret_cast<char*>(nv.value), nv.valuelen)});
+      ENVOY_LOG_MISC(trace, "decoded: {}, {}", absl::CEscape(decoded_headers.back().first),
+                     absl::CEscape(decoded_headers.back().second));
     }
   }
 
@@ -90,10 +96,15 @@ std::vector<nghttp2_nv> decodeHeaders(nghttp2_hd_inflater* inflater,
 }
 
 struct NvComparator {
-  inline bool operator()(const nghttp2_nv& a, const nghttp2_nv& b) {
-    absl::string_view a_str(reinterpret_cast<char*>(a.name), a.namelen);
-    absl::string_view b_str(reinterpret_cast<char*>(b.name), b.namelen);
-    return a_str.compare(b_str);
+  inline bool operator()(const nghttp2_nv& a, const nghttp2_nv& b) const {
+    absl::string_view a_name(reinterpret_cast<char*>(a.name), a.namelen);
+    absl::string_view b_name(reinterpret_cast<char*>(b.name), b.namelen);
+    if (a_name != b_name) {
+      return a_name < b_name;
+    }
+    absl::string_view a_val(reinterpret_cast<char*>(a.value), a.valuelen);
+    absl::string_view b_val(reinterpret_cast<char*>(b.value), b.valuelen);
+    return a_val < b_val;
   }
 };
 
@@ -108,8 +119,8 @@ DEFINE_PROTO_FUZZER(const test::common::http::http2::HpackTestCase& input) {
 
   // Create name value pairs from headers.
   std::vector<nghttp2_nv> input_nv = createNameValueArray(input.headers());
-  // Skip encoding empty headers. nghttp2 will throw a nullptr error on runtime if it receives a
-  // nullptr input.
+  // Skip encoding an empty header map. nghttp2 will throw a nullptr error on runtime if it receives
+  // a nullptr input.
   if (!input_nv.data()) {
     return;
   }
@@ -127,18 +138,19 @@ DEFINE_PROTO_FUZZER(const test::common::http::http2::HpackTestCase& input) {
   ASSERT(!payload.getRawSlices().empty());
 
   // Decode headers with nghttp2
-  std::vector<nghttp2_nv> output_nv = decodeHeaders(inflater, payload, input.end_headers());
+  std::vector<std::pair<std::string, std::string>> output_nv =
+      decodeHeaders(inflater, payload, input.end_headers());
 
   // Verify that decoded == encoded.
   ASSERT(input_nv.size() == output_nv.size());
   std::sort(input_nv.begin(), input_nv.end(), NvComparator());
-  std::sort(output_nv.begin(), output_nv.end(), NvComparator());
+  std::sort(output_nv.begin(), output_nv.end());
+
   for (size_t i = 0; i < input_nv.size(); i++) {
-    absl::string_view in_name = {reinterpret_cast<char*>(input_nv[i].name), input_nv[i].namelen};
-    absl::string_view out_name = {reinterpret_cast<char*>(output_nv[i].name), output_nv[i].namelen};
-    absl::string_view in_val = {reinterpret_cast<char*>(input_nv[i].value), input_nv[i].valuelen};
-    absl::string_view out_val = {reinterpret_cast<char*>(output_nv[i].value),
-                                 output_nv[i].valuelen};
+    std::string in_name = {reinterpret_cast<char*>(input_nv[i].name), input_nv[i].namelen};
+    std::string out_name = output_nv[i].first;
+    std::string in_val = {reinterpret_cast<char*>(input_nv[i].value), input_nv[i].valuelen};
+    std::string out_val = output_nv[i].second;
     ASSERT(in_name == out_name);
     ASSERT(in_val == out_val);
   }