Revert "Helper reallocate packet (#3110)" (#3263)

This reverts commit 13eed74.
microsoft · Feb 15, 2024 · 66087c5 · 66087c5
1 parent 6150135
commit 66087c5
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Showing 12 changed files with 12 additions and 114 deletions.
diff --git a/docs/eBpfExtensions.md b/docs/eBpfExtensions.md
@@ -130,7 +130,6 @@ Helper function IDs for different program types need not be unique.
 * `return_type`: Set the appropriate value for the `ebpf_return_type_t` enum that represents the return type of the
 helper function.
 * `arguments`: Array of (at most) five helper function arguments of type `ebpf_argument_type_t`.
-* `reallocate_packet`: Flag indicating if this helper function performs packet reallocation.
 
 #### `ebpf_argument_type_t` Enum
 This enum describes the various argument types that can be passed to an eBPF helper function. This is defined in the

diff --git a/include/ebpf_program_types.h b/include/ebpf_program_types.h
@@ -7,14 +7,12 @@
 
 #include <guiddef.h>
 #if !defined(NO_CRT) && !defined(_NO_CRT_STDIO_INLINE)
-#include <stdbool.h>
 #include <stdint.h>
 #else
 typedef unsigned char uint8_t;
 typedef unsigned int uint32_t;
 typedef unsigned long long uint64_t;
 typedef unsigned short wchar_t;
-#define bool _Bool
 #endif
 
 #define EBPF_MAX_PROGRAM_DESCRIPTOR_NAME_LENGTH 256
@@ -29,15 +27,12 @@ typedef struct _ebpf_program_type_descriptor
     char is_privileged;
 } ebpf_program_type_descriptor_t;
 
-#define HELPER_FUNCTION_REALLOCATE_PACKET 0x1
-
 typedef struct _ebpf_helper_function_prototype
 {
     uint32_t helper_id;
     const char* name;
     ebpf_return_type_t return_type;
     ebpf_argument_type_t arguments[5];
-    bool reallocate_packet : 1;
 } ebpf_helper_function_prototype_t;
 
 typedef struct _ebpf_program_info

diff --git a/libs/api_common/store_helper_internal.cpp b/libs/api_common/store_helper_internal.cpp
@@ -45,9 +45,8 @@ _load_helper_prototype(
 
         // Read serialized helper prototype information.
         char serialized_data[sizeof(ebpf_helper_function_prototype_t)] = {0};
-        bool reallocate_packet = false;
         size_t expected_size = sizeof(helper_prototype->helper_id) + sizeof(helper_prototype->return_type) +
-                               sizeof(helper_prototype->arguments) + sizeof(reallocate_packet);
+                               sizeof(helper_prototype->arguments);
 
         status = ebpf_read_registry_value_binary(
             helper_info_key, EBPF_HELPER_DATA_PROTOTYPE, (uint8_t*)serialized_data, expected_size);
@@ -67,10 +66,6 @@ _load_helper_prototype(
         memcpy(&helper_prototype->arguments, serialized_data + offset, sizeof(helper_prototype->arguments));
         offset += sizeof(helper_prototype->arguments);
 
-        memcpy(&reallocate_packet, serialized_data + offset, sizeof(reallocate_packet));
-        helper_prototype->reallocate_packet = reallocate_packet ? HELPER_FUNCTION_REALLOCATE_PACKET : 0;
-        offset += sizeof(reallocate_packet);
-
         helper_prototype->name =
             cxplat_duplicate_string(ebpf_down_cast_from_wstring(std::wstring(helper_name)).c_str());
         if (helper_prototype->name == nullptr) {

diff --git a/libs/api_common/windows_helpers.cpp b/libs/api_common/windows_helpers.cpp
@@ -61,7 +61,5 @@ get_helper_prototype_windows(int32_t n)
         verifier_prototype.argument_type[i] = raw_prototype->arguments[i];
     }
 
-    verifier_prototype.reallocate_packet = raw_prototype->reallocate_packet == TRUE;
-
     return verifier_prototype;
 }
diff --git a/libs/execution_context/ebpf_program.c b/libs/execution_context/ebpf_program.c
@@ -2063,7 +2063,6 @@ _IRQL_requires_max_(PASSIVE_LEVEL) static ebpf_result_t _ebpf_program_compute_pr
     //   b. Helper name.
     //   c. Helper return type.
     //   d. Helper argument types.
-    //   e. reallocate_packet flag (if set).
 
     // Note:
     // Order and fields being hashed is important. The order and fields being hashed must match the order and fields
@@ -2129,13 +2128,6 @@ _IRQL_requires_max_(PASSIVE_LEVEL) static ebpf_result_t _ebpf_program_compute_pr
                 goto Exit;
             }
         }
-
-        if (helper_function_prototype->reallocate_packet) {
-            result = EBPF_CRYPTOGRAPHIC_HASH_APPEND_STR(cryptographic_hash, "reallocate_packet");
-            if (result != EBPF_SUCCESS) {
-                goto Exit;
-            }
-        }
     }
     *hash_length = 0;
     result = ebpf_cryptographic_hash_get_hash_length(cryptographic_hash, hash_length);

diff --git a/libs/shared/ebpf_serialize.c b/libs/shared/ebpf_serialize.c
@@ -29,7 +29,6 @@ typedef struct _ebpf_serialized_helper_function_prototype
     uint32_t helper_id;
     ebpf_return_type_t return_type;
     ebpf_argument_type_t arguments[5];
-    uint8_t reallocate_packet;
     size_t name_length;
     uint8_t name[1];
 } ebpf_serialized_helper_function_prototype_t;
@@ -463,8 +462,6 @@ ebpf_serialize_program_info(
             for (uint16_t index = 0; index < EBPF_COUNT_OF(helper_prototype->arguments); index++) {
                 serialized_helper_prototype->arguments[index] = helper_prototype->arguments[index];
             }
-            serialized_helper_prototype->reallocate_packet =
-                helper_prototype->reallocate_packet ? HELPER_FUNCTION_REALLOCATE_PACKET : 0;
             serialized_helper_prototype->name_length = helper_function_name_length;
             // Copy the program type descriptor name buffer.
             memcpy(serialized_helper_prototype->name, helper_prototype->name, helper_function_name_length);
@@ -630,14 +627,12 @@ ebpf_deserialize_program_info(
             goto Exit;
         }
 
-        // Deserialize helper prototype.
+        // Serialize helper prototype.
         helper_prototype->helper_id = serialized_helper_prototype->helper_id;
         helper_prototype->return_type = serialized_helper_prototype->return_type;
         for (int i = 0; i < EBPF_COUNT_OF(helper_prototype->arguments); i++) {
             helper_prototype->arguments[i] = serialized_helper_prototype->arguments[i];
         }
-        helper_prototype->reallocate_packet =
-            serialized_helper_prototype->reallocate_packet == HELPER_FUNCTION_REALLOCATE_PACKET;
 
         // Adjust remaining buffer length.
         result = ebpf_safe_size_t_subtract(

diff --git a/libs/store_helper/ebpf_store_helper.c b/libs/store_helper/ebpf_store_helper.c
@@ -1,6 +1,7 @@
 // Copyright (c) Microsoft Corporation
 // SPDX-License-Identifier: MIT
 
+#include "ebpf_program_types.h"
 #include "ebpf_registry_helper.h"
 #include "ebpf_store_helper.h"
 #include "ebpf_windows.h"
@@ -40,7 +41,6 @@ _ebpf_store_update_helper_prototype(
     uint32_t offset;
     ebpf_store_key_t helper_function_key = NULL;
     char serialized_data[sizeof(ebpf_helper_function_prototype_t)] = {0};
-    const bool reallocate_packet = helper_info->reallocate_packet;
 
     wchar_t* wide_helper_name = ebpf_get_wstring_from_string(helper_info->name);
     if (wide_helper_name == NULL) {
@@ -63,9 +63,6 @@ _ebpf_store_update_helper_prototype(
     memcpy(serialized_data + offset, helper_info->arguments, sizeof(helper_info->arguments));
     offset += sizeof(helper_info->arguments);
 
-    memcpy(serialized_data + offset, &reallocate_packet, sizeof(reallocate_packet));
-    offset += sizeof(reallocate_packet);
-
     // Save the helper prototype data.
     result = ebpf_write_registry_value_binary(
         helper_function_key, EBPF_HELPER_DATA_PROTOTYPE, (uint8_t*)&serialized_data[0], offset);

diff --git a/netebpfext/net_ebpf_ext_program_info.h b/netebpfext/net_ebpf_ext_program_info.h
@@ -14,8 +14,7 @@ static const ebpf_helper_function_prototype_t _xdp_test_ebpf_extension_helper_fu
     {XDP_EXT_HELPER_FUNCTION_START + 1,
      "bpf_xdp_adjust_head",
      EBPF_RETURN_TYPE_INTEGER,
-     {EBPF_ARGUMENT_TYPE_PTR_TO_CTX, EBPF_ARGUMENT_TYPE_ANYTHING},
-     HELPER_FUNCTION_REALLOCATE_PACKET}};
+     {EBPF_ARGUMENT_TYPE_PTR_TO_CTX, EBPF_ARGUMENT_TYPE_ANYTHING}}};
 
 // XDP_TEST program information.
 static const ebpf_context_descriptor_t _ebpf_xdp_test_context_descriptor = {

diff --git a/tests/end_to_end/netsh_test.cpp b/tests/end_to_end/netsh_test.cpp
@@ -380,29 +380,6 @@ TEST_CASE("show verification droppacket_unsafe.o", "[netsh][verification]")
                   "\n");
 }
 
-TEST_CASE("show verification xdp_adjust_head_unsafe.o", "[netsh][verification]")
-{
-    _test_helper_netsh test_helper;
-    test_helper.initialize();
-
-    int result;
-    std::string output =
-        _run_netsh_command(handle_ebpf_show_verification, L"xdp_adjust_head_unsafe.o", L"xdp", nullptr, &result);
-    REQUIRE(result == ERROR_SUPPRESS_OUTPUT);
-    output = strip_paths(output);
-    REQUIRE(
-        output == "Verification failed\n"
-                  "\n"
-                  "Verification report:\n"
-                  "\n"
-                  "; ./tests/sample/unsafe/xdp_adjust_head_unsafe.c:42\n"
-                  ";     ethernet_header->Type = 0x0800;\n"
-                  "17: Upper bound must be at most packet_size (valid_access(r1.offset+12, width=2) for write)\n"
-                  "\n"
-                  "1 errors\n"
-                  "\n");
-}
-
 TEST_CASE("show verification printk_unsafe.o", "[netsh][verification]")
 {
     _test_helper_netsh test_helper;

diff --git a/tests/sample/unsafe/xdp_adjust_head_unsafe.c b/tests/sample/unsafe/xdp_adjust_head_unsafe.c
diff --git a/tools/bpf2c/bpf2c.cpp b/tools/bpf2c/bpf2c.cpp
@@ -116,9 +116,6 @@ get_program_info_type_hash(const std::vector<int32_t>& actual_helper_ids, const
                 hash_t::append_byte_range(
                     byte_range, program_info->program_type_specific_helper_prototype[index].arguments[argument]);
             }
-            if (program_info->program_type_specific_helper_prototype[index].reallocate_packet) {
-                hash_t::append_byte_range(byte_range, reinterpret_cast<const char*>("reallocate_packet"));
-            }
         }
     }
     hash_t hash(algorithm);

diff --git a/tools/bpf2c/bpf2c.vcxproj b/tools/bpf2c/bpf2c.vcxproj
@@ -86,13 +86,13 @@
   </ImportGroup>
   <PropertyGroup Label="UserMacros" />
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Debug|x64'">
-    <LinkIncremental>false</LinkIncremental>
+    <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='NativeOnlyDebug|x64'">
-    <LinkIncremental>false</LinkIncremental>
+    <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='FuzzerDebug|x64'">
-    <LinkIncremental>false</LinkIncremental>
+    <LinkIncremental>true</LinkIncremental>
   </PropertyGroup>
   <PropertyGroup Condition="'$(Configuration)|$(Platform)'=='Release|x64'">
     <LinkIncremental>false</LinkIncremental>
@@ -108,7 +108,7 @@
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
-      <GenerateDebugInformation>DebugFull</GenerateDebugInformation>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalDependencies>$(FuzzerLibs);%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
@@ -126,7 +126,7 @@
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
-      <GenerateDebugInformation>DebugFull</GenerateDebugInformation>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalDependencies>$(FuzzerLibs);%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
@@ -141,7 +141,7 @@
     </ClCompile>
     <Link>
       <SubSystem>Console</SubSystem>
-      <GenerateDebugInformation>DebugFull</GenerateDebugInformation>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalDependencies>$(FuzzerLibs);%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
@@ -159,7 +159,7 @@
       <SubSystem>Console</SubSystem>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <GenerateDebugInformation>DebugFull</GenerateDebugInformation>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalDependencies>$(FuzzerLibs);%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>
@@ -177,7 +177,7 @@
       <SubSystem>Console</SubSystem>
       <EnableCOMDATFolding>true</EnableCOMDATFolding>
       <OptimizeReferences>true</OptimizeReferences>
-      <GenerateDebugInformation>DebugFull</GenerateDebugInformation>
+      <GenerateDebugInformation>true</GenerateDebugInformation>
       <AdditionalDependencies>$(FuzzerLibs);%(AdditionalDependencies)</AdditionalDependencies>
     </Link>
     <PreBuildEvent>