implement std.sha256

Makefile

@@ -29,9 +29,9 @@ OD ?= od
 
 OPT ?= -O3
 
-CXXFLAGS ?= -g $(OPT) -Wall -Wextra -Woverloaded-virtual -pedantic -std=c++0x -fPIC -Iinclude -Ithird_party/md5 -Ithird_party/json
+CXXFLAGS ?= -g $(OPT) -Wall -Wextra -Woverloaded-virtual -pedantic -std=c++0x -fPIC -Iinclude -Ithird_party/json
 CFLAGS ?= -g $(OPT) -Wall -Wextra -pedantic -std=c99 -fPIC -Iinclude
-MAKEDEPENDFLAGS ?= -Iinclude -Ithird_party/md5 -Ithird_party/json
+MAKEDEPENDFLAGS ?= -Iinclude -Ithird_party/json
 EMCXXFLAGS = $(CXXFLAGS) -g0 -Os --memory-init-file 0 -s DISABLE_EXCEPTION_CATCHING=0 -s OUTLINING_LIMIT=10000 -s RESERVED_FUNCTION_POINTERS=20
 EMCFLAGS = $(CFLAGS) --memory-init-file 0 -s DISABLE_EXCEPTION_CATCHING=0
 LDFLAGS ?=
@@ -52,7 +52,7 @@ LIB_SRC = \
 	core/static_analysis.cpp \
 	core/string_utils.cpp \
 	core/vm.cpp \
-	third_party/md5/md5.cpp
+	hash/hash.cpp
 
 LIB_OBJ = $(LIB_SRC:.cpp=.o)
 
@@ -83,10 +83,10 @@ ALL_HEADERS = \
 	core/string_utils.h \
 	core/vm.h \
 	core/std.jsonnet.h \
+	hash/hash.h \
 	include/libjsonnet.h \
 	include/libjsonnet_fmt.h \
 	include/libjsonnet++.h \
-	third_party/md5/md5.h \
 	third_party/json/json.hpp
 
 default: jsonnet

WORKSPACE

@@ -1,35 +1,31 @@
 workspace(name = "jsonnet")
 
-# This local_repository looks silly but it makes io_bazel_rules_jsonnet use
-# _this_ jsonnet, not another downloaded copy.
-local_repository(
-    name = "jsonnet",
-    path = ".",
-)
+load("@bazel_tools//tools/build_defs/repo:git.bzl", "git_repository")
 
 git_repository(
     name = "io_bazel_rules_jsonnet",
     commit = "09ec18db5b9ad3129810f5f0ccc86363a8bfb6be",
     remote = "https://github.com/bazelbuild/rules_jsonnet.git",
 )
 
-new_git_repository(
+git_repository(
     name = "com_google_googletest",
     remote = "https://github.com/google/googletest.git",
 
     # If updating googletest version, also update CMakeLists.txt.in.
-    tag = "release-1.8.0",
-    build_file = "gmock.BUILD",
+    tag = "release-1.8.1",
 )
 
-bind(
-    name = "googletest",
-    actual = "@com_google_googletest//:googletest_no_main",
+git_repository(
+    name = "boringssl",
+    commit = "b8a5219531146b0907a72da8e62f331bb0d673c5",
+    remote = "https://boringssl.googlesource.com/boringssl",
 )
 
-bind(
-    name = "googletest_main",
-    actual = "@com_google_googletest//:googletest",
+git_repository(
+    name = "com_google_absl",
+    commit = "2a62fbdedf64673f7c858bc6487bd15bcd2ca180",
+    remote = "https://github.com/abseil/abseil-cpp.git",
 )
 
 load("//tools/build_defs:python_repo.bzl", "python_interpreter")

core/BUILD

@@ -28,15 +28,15 @@ cc_library(
         "unicode.h",
         "vm.h",
     ],
+    includes = ["."],
+    linkopts = ["-lm"],
     deps = [
+        ":hash",
         "//include:libjsonnet",
         "//include:libjsonnet_fmt",
         "//stdlib:std",
-        "//third_party/json:json",
-        "//third_party/md5:libmd5",
+        "//third_party/json",
     ],
-    linkopts = ["-lm"],
-    includes = ["."],
 )
 
 cc_test(
@@ -45,7 +45,7 @@ cc_test(
     deps = [
         ":libjsonnet",
         # Note: On Ubuntu, apt-get install libgtest-dev google-mock
-        "//external:googletest_main",
+        "@com_google_googletest//:gtest_main",
     ],
 )
 
@@ -54,7 +54,7 @@ cc_test(
     srcs = ["parser_test.cpp"],
     deps = [
         ":libjsonnet",
-        "//external:googletest_main",
+        "@com_google_googletest//:gtest_main",
     ],
 )
 
@@ -63,6 +63,21 @@ cc_test(
     srcs = ["libjsonnet_test.cpp"],
     deps = [
         ":libjsonnet",
-        "//external:googletest_main",
+        "@com_google_googletest//:gtest_main",
+    ],
+)
+
+cc_library(
+    name = "hash",
+    srcs = [
+        "hash.cpp",
+    ],
+    hdrs = [
+        "hash.h",
+    ],
+    visibility = ["//visibility:private"],
+    deps = [
+        "@boringssl//:crypto",
+        "@com_google_absl//absl/strings",
     ],
 )

core/desugarer.cpp

@@ -34,7 +34,7 @@ struct BuiltinDecl {
     std::vector<UString> params;
 };
 
-static unsigned long max_builtin = 37;
+static unsigned long max_builtin = 38;
 BuiltinDecl jsonnet_builtin_decl(unsigned long builtin)
 {
     switch (builtin) {
@@ -76,6 +76,7 @@ BuiltinDecl jsonnet_builtin_decl(unsigned long builtin)
         case 35: return {U"parseJson", {U"str"}};
         case 36: return {U"encodeUTF8", {U"str"}};
         case 37: return {U"decodeUTF8", {U"arr"}};
+        case 38: return {U"sha256", {U"str"}};
         default:
             std::cerr << "INTERNAL ERROR: Unrecognized builtin function: " << builtin << std::endl;
             std::abort();

core/hash.cpp

@@ -0,0 +1,35 @@
+#include "core/hash.h"
+
+#include "absl/strings/escaping.h"
+#include "openssl/bio.h"
+#include "openssl/digest.h"
+
+namespace jsonnet {
+namespace hash {
+
+namespace {
+
+std::string digest(const std::string& input, const EVP_MD* alg)
+{
+    uint8_t digest[EVP_MAX_MD_SIZE];
+    unsigned int digest_length = 0;
+    if (EVP_Digest(input.data(), input.size(), digest, &digest_length, alg, nullptr) != 1) {
+        return "";
+    }
+    return absl::BytesToHexString(
+        std::string(reinterpret_cast<const char*>(digest), digest_length));
+}
+}  // namespace
+
+std::string Sha256(const std::string& input)
+{
+    return digest(input, EVP_sha256());
+}
+
+std::string Md5(const std::string& input)
+{
+    return digest(input, EVP_md5());
+}
+
+}  // namespace hash
+}  // namespace jsonnet

core/hash.h

@@ -0,0 +1,13 @@
+#pragma once
+
+#include <string>
+
+namespace jsonnet {
+namespace hash {
+
+std::string Sha256(const std::string& input);
+
+std::string Md5(const std::string& input);
+
+}  // namespace hash
+}  // namespace jsonnet

core/vm.cpp

@@ -21,10 +21,10 @@ limitations under the License.
 #include <set>
 #include <string>
 
+#include "core/hash.h"
 #include "desugarer.h"
 #include "json.h"
 #include "json.hpp"
-#include "md5.h"
 #include "parser.h"
 #include "state.h"
 #include "static_analysis.h"
@@ -869,7 +869,12 @@ class Interpreter {
         builtins["extVar"] = &Interpreter::builtinExtVar;
         builtins["primitiveEquals"] = &Interpreter::builtinPrimitiveEquals;
         builtins["native"] = &Interpreter::builtinNative;
+#ifndef DISABLE_INSECURE_HASH
         builtins["md5"] = &Interpreter::builtinMd5;
+#else
+        builtins["md5"] = &Interpreter::builtinMd5Disabled;
+#endif
+        builtins["sha256"] = &Interpreter::builtinSha256;
         builtins["trace"] = &Interpreter::builtinTrace;
         builtins["splitLimit"] = &Interpreter::builtinSplitLimit;
         builtins["substr"] = &Interpreter::builtinSubstr;
@@ -1310,7 +1315,23 @@ class Interpreter {
 
         std::string value = encode_utf8(static_cast<HeapString *>(args[0].v.h)->value);
 
-        scratch = makeString(decode_utf8(md5(value)));
+        scratch = makeString(decode_utf8(jsonnet::hash::Md5(value)));
+        return nullptr;
+    }
+
+    const AST *builtinMd5Disabled(const LocationRange &loc, const std::vector<Value> &args)
+    {
+        throw makeError(
+            loc, "std.md5 was disabled at compile time because it is insecure. Use std.sha256.");
+    }
+
+    const AST *builtinSha256(const LocationRange &loc, const std::vector<Value> &args)
+    {
+        validateBuiltinArgs(loc, "sha255", args, {Value::STRING});
+
+        std::string value = encode_utf8(static_cast<HeapString *>(args[0].v.h)->value);
+
+        scratch = makeString(decode_utf8(jsonnet::hash::Sha256(value)));
         return nullptr;
     }
 

cpp/BUILD

@@ -15,6 +15,6 @@ cc_test(
     data = ["//cpp/testdata"],
     deps = [
         ":libjsonnet++",
-        "//external:googletest_main",
+        "@com_google_googletest//:gtest_main",
     ],
 )