Added support for horizontal secure XGBoost

src/processing/plugins/dummy_processor.cc → src/processing/plugins/mock_processor.cc

@@ -4,7 +4,7 @@
 #include <iostream>
 #include <cstring>
 #include <cstdint>
-#include "./dummy_processor.h"
+#include "./mock_processor.h"
 
 const char kSignature[] = "NVDADAM1";  // DAM (Direct Accessible Marshalling) V1
 const int64_t kPrefixLen = 24;
@@ -13,7 +13,7 @@ bool ValidDam(void *buffer, std::size_t size) {
   return size >= kPrefixLen && memcmp(buffer, kSignature, strlen(kSignature)) == 0;
 }
 
-void* DummyProcessor::ProcessGHPairs(std::size_t *size, const std::vector<double>& pairs) {
+void* MockProcessor::ProcessGHPairs(std::size_t *size, const std::vector<double>& pairs) {
   *size = kPrefixLen + pairs.size()*10*8;  // Assume encrypted size is 10x
 
   int64_t buf_size = *size;
@@ -39,13 +39,13 @@ void* DummyProcessor::ProcessGHPairs(std::size_t *size, const std::vector<double
 }
 
 
-void* DummyProcessor::HandleGHPairs(std::size_t *size, void *buffer, std::size_t buf_size) {
+void* MockProcessor::HandleGHPairs(std::size_t *size, void *buffer, std::size_t buf_size) {
   *size = buf_size;
   if (!ValidDam(buffer, *size)) {
     return buffer;
   }
 
-  // For dummy, this call is used to set gh_pairs for passive sites
+  // For mock, this call is used to set gh_pairs for passive sites
   if (!active_) {
     int8_t *ptr = static_cast<int8_t *>(buffer);
     ptr += kPrefixLen;
@@ -60,7 +60,7 @@ void* DummyProcessor::HandleGHPairs(std::size_t *size, void *buffer, std::size_t
   return buffer;
 }
 
-void *DummyProcessor::ProcessAggregation(std::size_t *size, std::map<int, std::vector<int>> nodes) {
+void *MockProcessor::ProcessAggregation(std::size_t *size, std::map<int, std::vector<int>> nodes) {
   int total_bin_size = cuts_.back();
   int histo_size = total_bin_size*2;
   *size = kPrefixLen + 8*histo_size*nodes.size();
@@ -93,15 +93,15 @@ void *DummyProcessor::ProcessAggregation(std::size_t *size, std::map<int, std::v
   return buf;
 }
 
-std::vector<double> DummyProcessor::HandleAggregation(void *buffer, std::size_t buf_size) {
+std::vector<double> MockProcessor::HandleAggregation(void *buffer, std::size_t buf_size) {
   std::vector<double> result = std::vector<double>();
 
   int8_t* ptr = static_cast<int8_t *>(buffer);
   auto rest_size = buf_size;
 
   while (rest_size > kPrefixLen) {
     if (!ValidDam(ptr, rest_size)) {
-        continue;
+        break;
     }
     int64_t *size_ptr = reinterpret_cast<int64_t *>(ptr + 8);
     double *array_start = reinterpret_cast<double *>(ptr + kPrefixLen);
@@ -113,3 +113,62 @@ std::vector<double> DummyProcessor::HandleAggregation(void *buffer, std::size_t
 
   return result;
 }
+
+void* MockProcessor::ProcessHistograms(std::size_t *size, const std::vector<double>& histograms) {
+    *size = kPrefixLen + histograms.size()*10*8;  // Assume encrypted size is 10x
+
+    int64_t buf_size = *size;
+    // This memory needs to be freed
+    char *buf = static_cast<char *>(malloc(buf_size));
+    memcpy(buf, kSignature, strlen(kSignature));
+    memcpy(buf + 8, &buf_size, 8);
+    memcpy(buf + 16, &kDataTypeAggregatedHisto, 8);
+
+    // Simulate encryption by duplicating value 10 times
+    int index = kPrefixLen;
+    for (auto value : histograms) {
+        for (std::size_t i = 0; i < 10; i++) {
+            memcpy(buf+index, &value, 8);
+            index += 8;
+        }
+    }
+
+    return buf;
+}
+
+std::vector<double> MockProcessor::HandleHistograms(void *buffer, std::size_t buf_size) {
+    std::vector<double> result = std::vector<double>();
+
+    int8_t* ptr = static_cast<int8_t *>(buffer);
+    auto rest_size = buf_size;
+
+    while (rest_size > kPrefixLen) {
+        if (!ValidDam(ptr, rest_size)) {
+            break;
+        }
+        int64_t *size_ptr = reinterpret_cast<int64_t *>(ptr + 8);
+        double *array_start = reinterpret_cast<double *>(ptr + kPrefixLen);
+        auto array_size = (*size_ptr - kPrefixLen)/8;
+        auto empty = result.empty();
+        if (!empty) {
+            if (result.size() != array_size / 10) {
+                std::cout << "Histogram size doesn't match " << result.size() << " != " << array_size << std::endl;
+                return result;
+            }
+        }
+
+        for (std::size_t i = 0; i < array_size/10; i++) {
+            auto value = array_start[i*10];
+            if (empty) {
+                result.push_back(value);
+            } else {
+                result[i] += value;
+            }
+        }
+
+        rest_size -= *size_ptr;
+        ptr = ptr + *size_ptr;
+    }
+
+    return result;
+}

src/processing/plugins/dummy_processor.h → src/processing/plugins/mock_processor.h

@@ -10,8 +10,9 @@
 //  Data type definition
 const int64_t kDataTypeGHPairs = 1;
 const int64_t kDataTypeHisto = 2;
+const int64_t kDataTypeAggregatedHisto = 3;
 
-class DummyProcessor: public processing::Processor {
+class MockProcessor: public processing::Processor {
  private:
     bool active_ = false;
     const std::map<std::string, std::string> *params_{nullptr};
@@ -50,4 +51,8 @@ class DummyProcessor: public processing::Processor {
     void *ProcessAggregation(size_t *size, std::map<int, std::vector<int>> nodes) override;
 
     std::vector<double> HandleAggregation(void *buffer, size_t buf_size) override;
+
+    void *ProcessHistograms(size_t *size, const std::vector<double>& histograms) override;
+
+    std::vector<double> HandleHistograms(void *buffer, size_t buf_size) override;
 };

src/processing/processor.h

@@ -12,7 +12,7 @@
 namespace processing {
 
 const char kLibraryPath[] = "LIBRARY_PATH";
-const char kDummyProcessor[] = "dummy";
+const char kMockProcessor[] = "mock";
 const char kLoadFunc[] = "LoadProcessor";
 
 /*! \brief An processor interface to handle tasks that require external library through plugins */
@@ -76,7 +76,7 @@ class Processor {
      * \param size The output buffer size
      * \param nodes Map of node and the rows belong to this node
      *
-     * \return The encoded buffer to be sent via AllGather
+     * \return The encoded buffer to be sent via AllGatherV
      */
     virtual void *ProcessAggregation(size_t *size, std::map<int, std::vector<int>> nodes) = 0;
 
@@ -90,16 +90,32 @@ class Processor {
      *     site1_node1, site1_node2 site1_node3, site2_node1, site2_node2, site2_node3
      */
     virtual std::vector<double> HandleAggregation(void *buffer, size_t buf_size) = 0;
+
+    /*!
+     * \brief Prepare histograms for further processing
+     *
+     * \param size The output buffer size
+     * \param histograms Flattened array of histograms for all features
+     *
+     * \return The encoded buffer to be sent via AllGatherV
+     */
+    virtual void *ProcessHistograms(size_t *size, const std::vector<double>& histograms) = 0;
+
+    /*!
+     * \brief Handle processed histograms
+     *
+     * \param buffer Buffer from allgatherV
+     * \param buf_size The size of the buffer
+     *
+     * \return A flattened vector of histograms for all features
+     */
+    virtual std::vector<double> HandleHistograms(void *buffer, size_t buf_size) = 0;
 };
 
 class ProcessorLoader {
  private:
     std::map<std::string, std::string> params;
-#if defined(_WIN32)
-    HMODULE handle_ = NULL;
-#else
     void *handle_ = NULL;
-#endif
 
  public:
     ProcessorLoader(): params{} {}

src/processing/processor_loader.cc

@@ -4,28 +4,28 @@
 
 #include <iostream>
 
-#if defined(_WIN32)
+#if defined(_WIN32) || defined(_WIN64)
 #include <windows.h>
 #else
 #include <dlfcn.h>
 #endif
 
 #include "./processor.h"
-#include "plugins/dummy_processor.h"
+#include "plugins/mock_processor.h"
 
 namespace processing {
     using LoadFunc = Processor *(const char *);
 
     Processor* ProcessorLoader::load(const std::string& plugin_name) {
         // Dummy processor for unit testing without loading a shared library
-        if (plugin_name == kDummyProcessor) {
-            return new DummyProcessor();
+        if (plugin_name == kMockProcessor) {
+            return new MockProcessor();
         }
 
         auto lib_name = "libproc_" + plugin_name;
 
         auto extension =
-#if defined(_WIN32)
+#if defined(_WIN32) || defined(_WIN64)
             ".dll";
 #elif defined(__APPLE__) || defined(__MACH__)
             ".dylib";
@@ -46,19 +46,18 @@ namespace processing {
             lib_path = p + lib_file_name;
         }
 
-#if defined(_WIN32)
-        HMODULE handle_ = LoadLibrary(lib_path.c_str());
+#if defined(_WIN32) || defined(_WIN64)
+        handle_ = reinterpret_cast<void *>(LoadLibrary(lib_path.c_str()));
         if (!handle_) {
             std::cerr << "Failed to load the dynamic library" << std::endl;
             return NULL;
         }
 
-        void* func_ptr = GetProcAddress(handle_, kLoadFunc);
+        void* func_ptr = reinterpret_cast<void *>(GetProcAddress((HMODULE)handle_, kLoadFunc));
         if (!func_ptr) {
             std::cerr << "Failed to find loader function." << std::endl;
             return NULL;
         }
-
 #else
         handle_ = dlopen(lib_path.c_str(), RTLD_LAZY);
         if (!handle_) {
@@ -70,7 +69,6 @@ namespace processing {
             std::cerr << "Failed to find loader function: " << dlerror() << std::endl;
             return NULL;
         }
-
 #endif
 
         auto func = reinterpret_cast<LoadFunc *>(func_ptr);