Auto merge of #77008 - fortanix:raoul/lvi-tests, r=Mark-Simulacrum

LVI hardening tests

Mitigating the speculative execution LVI attack against SGX enclaves requires compiler changes (i.e., adding lfences). This pull requests adds various tests to check if this happens correctly.

src/bootstrap/native.rs

@@ -630,7 +630,14 @@ impl Step for TestHelpers {
         if builder.config.dry_run {
             return;
         }
-        let target = self.target;
+        // The x86_64-fortanix-unknown-sgx target doesn't have a working C
+        // toolchain. However, some x86_64 ELF objects can be linked
+        // without issues. Use this hack to compile the test helpers.
+        let target = if self.target == "x86_64-fortanix-unknown-sgx" {
+            TargetSelection::from_user("x86_64-unknown-linux-gnu")
+        } else {
+            self.target
+        };
         let dst = builder.test_helpers_out(target);
         let src = builder.src.join("src/test/auxiliary/rust_test_helpers.c");
         if up_to_date(&src, &dst.join("librust_test_helpers.a")) {
@@ -654,7 +661,6 @@ impl Step for TestHelpers {
             }
             cfg.compiler(builder.cc(target));
         }
-
         cfg.cargo_metadata(false)
             .out_dir(&dst)
             .target(&target.triple)

src/test/assembly/x86_64-fortanix-unknown-sgx-lvi-generic-load.rs

@@ -0,0 +1,17 @@
+// Test LVI load hardening on SGX enclave code
+
+// assembly-output: emit-asm
+// compile-flags: --crate-type staticlib
+// only-x86_64-fortanix-unknown-sgx
+
+#[no_mangle]
+pub extern fn plus_one(r: &mut u64) {
+    *r = *r + 1;
+}
+
+// CHECK: plus_one
+// CHECK: lfence
+// CHECK-NEXT: addq
+// CHECK: popq [[REGISTER:%[a-z]+]]
+// CHECK-NEXT: lfence
+// CHECK-NEXT: jmpq *[[REGISTER]]

src/test/assembly/x86_64-fortanix-unknown-sgx-lvi-generic-ret.rs

@@ -0,0 +1,12 @@
+// Test LVI ret hardening on generic rust code
+
+// assembly-output: emit-asm
+// compile-flags: --crate-type staticlib
+// only-x86_64-fortanix-unknown-sgx
+
+#[no_mangle]
+pub extern fn myret() {}
+// CHECK: myret:
+// CHECK: popq [[REGISTER:%[a-z]+]]
+// CHECK-NEXT: lfence
+// CHECK-NEXT: jmpq *[[REGISTER]]

src/test/assembly/x86_64-fortanix-unknown-sgx-lvi-inline-assembly.rs

@@ -0,0 +1,41 @@
+// Test LVI load hardening on SGX inline assembly code
+
+// assembly-output: emit-asm
+// compile-flags: --crate-type staticlib
+// only-x86_64-fortanix-unknown-sgx
+
+#![feature(asm)]
+
+#[no_mangle]
+pub extern fn get(ptr: *const u64) -> u64 {
+    let value : u64;
+    unsafe {
+        asm!(".start_inline_asm:",
+            "mov {}, [{}]",
+            ".end_inline_asm:",
+            out(reg) value,
+            in(reg) ptr);
+    }
+    value
+}
+
+// CHECK: get
+// CHECK: .start_inline_asm
+// CHECK-NEXT: movq
+// CHECK-NEXT: lfence
+// CHECK-NEXT: .end_inline_asm
+
+#[no_mangle]
+pub extern fn myret() {
+    unsafe {
+        asm!(".start_myret_inline_asm:
+            ret
+            .end_myret_inline_asm:");
+    }
+}
+
+// CHECK: myret
+// CHECK: .start_myret_inline_asm
+// CHECK-NEXT: shlq $0, (%rsp)
+// CHECK-NEXT: lfence
+// CHECK-NEXT: retq

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/Makefile

@@ -0,0 +1,23 @@
+-include ../../run-make-fulldeps/tools.mk
+
+#only-x86_64-fortanix-unknown-sgx
+
+# For cargo setting
+export RUSTC := $(RUSTC_ORIGINAL)
+export LD_LIBRARY_PATH := $(HOST_RPATH_DIR)
+# We need to be outside of 'src' dir in order to run cargo
+export WORK_DIR := $(TMPDIR)
+export TEST_DIR := $(shell pwd)
+
+## clean up unused env variables which might cause harm.
+unexport RUSTC_LINKER
+unexport RUSTC_BOOTSTRAP
+unexport RUST_BUILD_STAGE
+unexport RUST_TEST_THREADS
+unexport RUST_TEST_TMPDIR
+unexport AR
+unexport CC
+unexport CXX
+
+all:
+	bash script.sh

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cc_plus_one_asm.checks

@@ -0,0 +1,8 @@
+CHECK: cc_plus_one_asm
+CHECK-NEXT: movl
+CHECK-NEXT: lfence
+CHECK-NEXT: inc
+CHECK-NEXT: notq (%rsp)
+CHECK-NEXT: notq (%rsp)
+CHECK-NEXT: lfence
+CHECK-NEXT: retq

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cc_plus_one_c.checks

@@ -0,0 +1,6 @@
+CHECK: cc_plus_one_c
+CHECK:      lfence
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cc_plus_one_c_asm.checks

@@ -0,0 +1,15 @@
+CHECK: cc_plus_one_c_asm
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK-NEXT: incl
+CHECK-NEXT: jmp
+CHECK-NEXT: shlq    $0, (%rsp)
+CHECK-NEXT: lfence
+CHECK-NEXT: retq
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cc_plus_one_cxx.checks

@@ -0,0 +1,6 @@
+CHECK: cc_plus_one_cxx
+CHECK:      lfence
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cc_plus_one_cxx_asm.checks

@@ -0,0 +1,16 @@
+CHECK: cc_plus_one_cxx_asm
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      movl
+CHECK:      lfence
+CHECK:      lfence
+CHECK-NEXT: incl
+CHECK-NEXT: jmp     0x{{[[:xdigit:]]+}} <cc_plus_one_cxx_asm+0x{{[[:xdigit:]]+}}>
+CHECK-NEXT: shlq    $0, (%rsp)
+CHECK-NEXT: lfence
+CHECK-NEXT: retq
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cmake_plus_one_asm.checks

@@ -0,0 +1,7 @@
+CHECK: cmake_plus_one_asm
+CHECK-NEXT: movl
+CHECK-NEXT: lfence
+CHECK-NEXT: incl
+CHECK-NEXT: shlq    $0, (%rsp)
+CHECK-NEXT: lfence
+CHECK-NEXT: retq

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cmake_plus_one_c.checks

@@ -0,0 +1,6 @@
+CHECK: cmake_plus_one_c
+CHECK:      lfence
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cmake_plus_one_c_asm.checks

@@ -0,0 +1,16 @@
+CHECK: cmake_plus_one_c_asm
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      movl
+CHECK:      lfence
+CHECK-NEXT: incl
+CHECK-NEXT: jmp     0x{{[[:xdigit:]]+}} <cmake_plus_one_c_asm+0x{{[[:xdigit:]]+}}>
+CHECK-NEXT: shlq    $0, (%rsp)
+CHECK-NEXT: lfence
+CHECK-NEXT: retq
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cmake_plus_one_c_global_asm.checks

@@ -0,0 +1,2 @@
+CHECK: cmake_plus_one_c_global_asm
+CHECK: lfence

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cmake_plus_one_cxx.checks

@@ -0,0 +1,6 @@
+CHECK: cmake_plus_one_cxx
+CHECK:      lfence
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cmake_plus_one_cxx_asm.checks

@@ -0,0 +1,16 @@
+CHECK: cmake_plus_one_cxx_asm
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      lfence
+CHECK:      movl
+CHECK:      lfence
+CHECK-NEXT: incl
+CHECK-NEXT: jmp     0x{{[[:xdigit:]]+}} <cmake_plus_one_cxx_asm+0x{{[[:xdigit:]]+}}>
+CHECK-NEXT: shlq    $0, (%rsp)
+CHECK-NEXT: lfence
+CHECK-NEXT: retq
+CHECK:      popq
+CHECK-NEXT: popq [[REGISTER:%[a-z]+]]
+CHECK-NEXT: lfence
+CHECK-NEXT: jmpq *[[REGISTER]]

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/cmake_plus_one_cxx_global_asm.checks

@@ -0,0 +1,2 @@
+CHECK: cmake_plus_one_cxx_global_asm
+CHECK: lfence

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/enclave/Cargo.toml

@@ -0,0 +1,13 @@
+[package]
+name = "enclave"
+version = "0.1.0"
+authors = ["Raoul Strackx <raoul.strackx@fortanix.com>"]
+edition = "2018"
+
+# See more keys and their definitions at https://doc.rust-lang.org/cargo/reference/manifest.html
+
+[dependencies]
+
+[build-dependencies]
+cc = "1.0"
+cmake = "0.1"

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/enclave/build.rs

@@ -0,0 +1,30 @@
+fn main() {
+    cc::Build::new()
+        .file("foo.c")
+        .compile("foo_c");
+
+    cc::Build::new()
+        .file("foo_asm.s")
+        .compile("foo_asm");
+
+    cc::Build::new()
+        .cpp(true)
+        .cpp_set_stdlib(None)
+        .file("foo_cxx.cpp")
+        .compile("foo_cxx");
+
+    // When the cmake crate detects the clang compiler, it passes the
+    //  "--target" argument to the linker which subsequently fails. The
+    //  `CMAKE_C_COMPILER_FORCED` option makes sure that `cmake` does not
+    //  tries to test the compiler. From version 3.6 the option
+    //  `CMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY` can be used
+    //  https://cmake.org/cmake/help/v3.5/module/CMakeForceCompiler.html
+    let dst = cmake::Config::new("libcmake_foo")
+                .build_target("cmake_foo")
+                .define("CMAKE_C_COMPILER_FORCED", "1")
+                .define("CMAKE_CXX_COMPILER_FORCED", "1")
+                .define("CMAKE_TRY_COMPILE_TARGET_TYPE=STATIC_LIBRARY", "1")
+                .build();
+    println!("cargo:rustc-link-search=native={}/build/", dst.display());
+    println!("cargo:rustc-link-lib=static=cmake_foo");
+}

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/enclave/foo.c

@@ -0,0 +1,18 @@
+int cc_plus_one_c(int *arg) {
+    return *arg + 1;
+}
+
+int cc_plus_one_c_asm(int *arg) {
+    int value = 0;
+
+    asm volatile ( "    movl (%1), %0\n"
+                   "    inc %0\n"
+                   "    jmp 1f\n"
+                   "    retq\n"  // never executed, but a shortcut to determine how
+                                 // the assembler deals with `ret` instructions
+                   "1:\n"
+                   : "=r"(value)
+                   : "r"(arg) );
+
+    return value;
+}

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/enclave/foo_asm.s

@@ -0,0 +1,7 @@
+    .text
+    .global cc_plus_one_asm
+    .type cc_plus_one_asm, @function
+cc_plus_one_asm:
+    movl (%rdi), %eax
+    inc %eax
+    retq

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/enclave/foo_cxx.cpp

@@ -0,0 +1,21 @@
+extern "C" int cc_plus_one_cxx(int *arg);
+extern "C" int cc_plus_one_cxx_asm(int *arg);
+
+int cc_plus_one_cxx(int *arg) {
+    return *arg + 1;
+}
+
+int cc_plus_one_cxx_asm(int *arg) {
+    int value = 0;
+
+    asm volatile ( "    movl (%1), %0\n"
+                   "    inc %0\n"
+                   "    jmp 1f\n"
+                   "    retq\n"  // never executed, but a shortcut to determine how
+                                 // the assembler deals with `ret` instructions
+                   "1:\n"
+                   : "=r"(value)
+                   : "r"(arg) );
+
+    return value;
+}

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/enclave/libcmake_foo/CMakeLists.txt

@@ -0,0 +1,33 @@
+enable_language(C CXX ASM)
+
+set(C_SOURCES
+    src/foo.c
+    )
+
+set_source_files_properties(${C_SOURCES}
+                            PROPERTIES
+                            LANGUAGE C)
+
+set(CXX_SOURCES
+    src/foo_cxx.cpp
+    )
+
+set_source_files_properties(${CXX_SOURCES}
+                            PROPERTIES
+                            LANGUAGE CXX)
+
+set(ASM_SOURCES
+    src/foo_asm.s
+    )
+
+set_source_files_properties(${ASM_SOURCES}
+                            PROPERTIES
+                            LANGUAGE ASM)
+
+set(SOURCES
+    ${C_SOURCES}
+    ${CXX_SOURCES}
+    ${ASM_SOURCES})
+
+add_library(cmake_foo STATIC
+    ${SOURCES})

src/test/run-make/x86_64-fortanix-unknown-sgx-lvi/enclave/libcmake_foo/src/foo.c

@@ -0,0 +1,26 @@
+int cmake_plus_one_c(int *arg) {
+    return *arg + 1;
+}
+
+int cmake_plus_one_c_asm(int *arg) {
+    int value = 0;
+
+    asm volatile ( "    movl (%1), %0\n"
+                   "    inc %0\n"
+                   "    jmp 1f\n"
+                   "    retq\n"  // never executed, but a shortcut to determine how
+                                 // the assembler deals with `ret` instructions
+                   "1:\n"
+                   : "=r"(value)
+                   : "r"(arg) );
+
+    return value;
+}
+
+asm(".text\n"
+"    .global cmake_plus_one_c_global_asm\n"
+"    .type cmake_plus_one_c_global_asm, @function\n"
+"cmake_plus_one_c_global_asm:\n"
+"    movl (%rdi), %eax\n"
+"    inc %eax\n"
+"    retq\n" );