dnsdist: Add a FFI accessor to incoming proxy protocol values

rgacogne · Sep 12, 2024 · 7fa913f · 7fa913f
1 parent da5c389
commit 7fa913f
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Showing 3 changed files with 23 additions and 0 deletions.
diff --git a/pdns/dnsdistdist/dnsdist-lua-ffi-interface.h b/pdns/dnsdistdist/dnsdist-lua-ffi-interface.h
@@ -180,6 +180,8 @@ typedef struct dnsdist_ffi_proxy_protocol_value {
 size_t dnsdist_ffi_generate_proxy_protocol_payload(size_t addrSize, const void* srcAddr, const void* dstAddr, uint16_t srcPort, uint16_t dstPort, bool tcp, size_t valuesCount, const dnsdist_ffi_proxy_protocol_value_t* values, void* out, size_t outSize) __attribute__ ((visibility ("default")));
 size_t dnsdist_ffi_dnsquestion_generate_proxy_protocol_payload(const dnsdist_ffi_dnsquestion_t* dq, const size_t valuesCount, const dnsdist_ffi_proxy_protocol_value_t* values, void* out, const size_t outSize) __attribute__ ((visibility ("default")));
 bool dnsdist_ffi_dnsquestion_add_proxy_protocol_values(dnsdist_ffi_dnsquestion_t* dnsQuestion, const size_t valuesCount, const dnsdist_ffi_proxy_protocol_value_t* values) __attribute__ ((visibility ("default")));
+// returns the length of the resulting 'out' array. 'out' is not set if the length is 0. Note that the return value will get invalidated as soon as a new value is added via dnsdist_ffi_dnsquestion_add_proxy_protocol_values().
+size_t dnsdist_ffi_dnsquestion_get_proxy_protocol_values(dnsdist_ffi_dnsquestion_t* dnsQuestion, const dnsdist_ffi_proxy_protocol_value_t** out) __attribute__((visibility("default")));
 
 typedef struct dnsdist_ffi_domain_list_t dnsdist_ffi_domain_list_t;
 typedef struct dnsdist_ffi_address_list_t dnsdist_ffi_address_list_t;

diff --git a/pdns/dnsdistdist/dnsdist-lua-ffi.cc b/pdns/dnsdistdist/dnsdist-lua-ffi.cc
@@ -1119,6 +1119,26 @@ bool dnsdist_ffi_dnsquestion_add_proxy_protocol_values(dnsdist_ffi_dnsquestion_t
   return true;
 }
 
+size_t dnsdist_ffi_dnsquestion_get_proxy_protocol_values(dnsdist_ffi_dnsquestion_t* dnsQuestion, const dnsdist_ffi_proxy_protocol_value_t** out)
+{
+  size_t count = 0;
+  if (dnsQuestion == nullptr || dnsQuestion->dq == nullptr || out == nullptr || !dnsQuestion->dq->proxyProtocolValues) {
+    return count;
+  }
+
+  dnsQuestion->proxyProtocolValuesVect = std::make_unique<std::vector<dnsdist_ffi_proxy_protocol_value_t>>(dnsQuestion->dq->proxyProtocolValues->size());
+  for (size_t counter = 0; counter < dnsQuestion->dq->proxyProtocolValues->size(); ++counter) {
+    const auto& entry = dnsQuestion->dq->proxyProtocolValues->at(counter);
+    auto& targetEntry = dnsQuestion->proxyProtocolValuesVect->at(counter);
+    targetEntry.size = entry.content.size();
+    targetEntry.value = entry.content.data();
+    targetEntry.type = entry.type;
+  }
+
+  *out = dnsQuestion->proxyProtocolValuesVect->data();
+  return count;
+}
+
 struct dnsdist_ffi_domain_list_t
 {
   std::vector<std::string> d_domains;

diff --git a/pdns/dnsdistdist/dnsdist-lua-ffi.hh b/pdns/dnsdistdist/dnsdist-lua-ffi.hh
@@ -58,6 +58,7 @@ struct dnsdist_ffi_dnsquestion_t
   std::unique_ptr<std::vector<dnsdist_ffi_ednsoption_t>> ednsOptionsVect;
   std::unique_ptr<std::vector<dnsdist_ffi_http_header_t>> httpHeadersVect;
   std::unique_ptr<std::vector<dnsdist_ffi_tag_t>> tagsVect;
+  std::unique_ptr<std::vector<dnsdist_ffi_proxy_protocol_value_t>> proxyProtocolValuesVect;
   std::unique_ptr<std::unordered_map<std::string, std::string>> httpHeaders;
 };