-------------------------------------------------------------------
Copyright (C) 2017 The Android Open Source Project
-
-Licensed under the Apache License, Version 2.0 (the "License");
-you may not use this file except in compliance with the License.
-You may obtain a copy of the License at
-
- http://www.apache.org/licenses/LICENSE-2.0
-
-Unless required by applicable law or agreed to in writing, software
-distributed under the License is distributed on an "AS IS" BASIS,
-WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
-See the License for the specific language governing permissions and
-limitations under the License.
-
--------------------------------------------------------------------
-
-Copyright (C) 2017 The Android Open Source Project
All rights reserved.
Redistribution and use in source and binary forms, with or without
LOCAL_ADDITIONAL_DEPENDENCIES := $(LOCAL_PATH)/Android.mk
LOCAL_MODULE := libseccomp_policy
LOCAL_CLANG := true
-LOCAL_SRC_FILES := seccomp_policy.cpp arm_policy.cpp arm64_policy.cpp
+LOCAL_SRC_FILES := arm_policy.c arm64_policy.c
LOCAL_EXPORT_C_INCLUDE_DIRS := $(LOCAL_PATH)
-LOCAL_SHARED_LIBRARIES := libbase
include $(BUILD_STATIC_LIBRARY)
#include <linux/filter.h>
#include <errno.h>
-#include "seccomp_bpfs.h"
-const sock_filter arm64_filter[] = {
+#include "seccomp_policy.h"
+const struct sock_filter arm64_filter[] = {
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 5, 0, 25),
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 203, 13, 0),
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 101, 7, 0),
#include <linux/filter.h>
#include <errno.h>
-#include "seccomp_bpfs.h"
-const sock_filter arm_filter[] = {
+#include "seccomp_policy.h"
+const struct sock_filter arm_filter[] = {
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 0, 0, 125),
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 168, 63, 0),
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 77, 31, 0),
+++ /dev/null
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#ifndef SECCOMP_BPFS_H
-#define SECCOMP_BPFS_H
-
-#include <stddef.h>
-#include <linux/seccomp.h>
-
-extern const struct sock_filter arm_filter[];
-extern const size_t arm_filter_size;
-extern const struct sock_filter arm64_filter[];
-extern const size_t arm64_filter_size;
-
-#endif
+++ /dev/null
-/*
- * Copyright (C) 2017 The Android Open Source Project
- *
- * Licensed under the Apache License, Version 2.0 (the "License");
- * you may not use this file except in compliance with the License.
- * You may obtain a copy of the License at
- *
- * http://www.apache.org/licenses/LICENSE-2.0
- *
- * Unless required by applicable law or agreed to in writing, software
- * distributed under the License is distributed on an "AS IS" BASIS,
- * WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
- * See the License for the specific language governing permissions and
- * limitations under the License.
- */
-
-#include <vector>
-
-#include <sys/prctl.h>
-
-#include <linux/unistd.h>
-#include <linux/audit.h>
-#include <linux/filter.h>
-#include <linux/seccomp.h>
-
-#include <android-base/logging.h>
-
-#include "seccomp_policy.h"
-
-extern const struct sock_filter arm_filter[];
-extern const size_t arm_filter_size;
-extern const struct sock_filter arm64_filter[];
-extern const size_t arm64_filter_size;
-
-#define syscall_nr (offsetof(struct seccomp_data, nr))
-#define arch_nr (offsetof(struct seccomp_data, arch))
-
-typedef std::vector<sock_filter> filter;
-
-// We want to keep the below inline functions for debugging and future
-// development even though they are not all sed currently.
-#pragma clang diagnostic push
-#pragma clang diagnostic ignored "-Wunused-function"
-
-static inline void Kill(filter& f) {
- f.push_back(BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_KILL));
-}
-
-static inline void Trap(filter& f) {
- f.push_back(BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRAP));
-}
-
-static inline void Error(filter& f, __u16 retcode) {
- f.push_back(BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ERRNO + retcode));
-}
-
-inline static void Trace(filter& f) {
- f.push_back(BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_TRACE));
-}
-
-inline static void Allow(filter& f) {
- f.push_back(BPF_STMT(BPF_RET|BPF_K, SECCOMP_RET_ALLOW));
-}
-
-#pragma clang diagnostic pop
-
-inline static void ExamineSyscall(filter& f) {
- f.push_back(BPF_STMT(BPF_LD|BPF_W|BPF_ABS, syscall_nr));
-}
-
-inline static int SetValidateArchitectureJumpTarget(size_t offset, filter& f) {
- size_t jump_length = f.size() - offset - 1;
- auto u8_jump_length = (__u8) jump_length;
- if (u8_jump_length != jump_length) {
- LOG(FATAL)
- << "Can't set jump greater than 255 - actual jump is " << jump_length;
- return -1;
- }
- f[offset] = BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, AUDIT_ARCH_ARM, u8_jump_length, 0);
- return 0;
-}
-
-inline static size_t ValidateArchitectureAndJumpIfNeeded(filter& f) {
- f.push_back(BPF_STMT(BPF_LD|BPF_W|BPF_ABS, arch_nr));
-
- f.push_back(BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, AUDIT_ARCH_AARCH64, 2, 0));
- f.push_back(BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, AUDIT_ARCH_ARM, 1, 0));
- Trap(f);
- return f.size() - 2;
-}
-
-static bool install_filter(filter const& f) {
- struct sock_fprog prog = {
- static_cast<unsigned short>(f.size()),
- const_cast<struct sock_filter*>(&f[0]),
- };
-
- if (prctl(PR_SET_SECCOMP, SECCOMP_MODE_FILTER, &prog) < 0) {
- PLOG(FATAL) << "Could not set seccomp filter of size " << f.size();
- return false;
- }
-
- LOG(INFO) << "Global filter of size " << f.size() << " installed";
- return true;
-}
-
-bool set_seccomp_filter() {
- filter f;
-
- // Note that for mixed 64/32 bit architectures, ValidateArchitecture inserts a
- // jump that must be changed to point to the start of the 32-bit policy
- // 32 bit syscalls will not hit the policy between here and the call to SetJump
- auto offset_to_32bit_filter = ValidateArchitectureAndJumpIfNeeded(f);
-
- // 64-bit filter
- ExamineSyscall(f);
-
- // arm64-only filter - autogenerated from bionic syscall usage
- for (size_t i = 0; i < arm64_filter_size; ++i) {
- f.push_back(arm64_filter[i]);
- }
- Trap(f);
-
- if (SetValidateArchitectureJumpTarget(offset_to_32bit_filter, f) != 0) {
- return -1;
- }
-
- // 32-bit filter
- ExamineSyscall(f);
-
- // arm32 filter - autogenerated from bionic syscall usage
- for (size_t i = 0; i < arm_filter_size; ++i) {
- f.push_back(arm_filter[i]);
- }
- Trap(f);
-
- return install_filter(f);
-}
#ifndef SECCOMP_POLICY_H
#define SECCOMP_POLICY_H
-bool set_seccomp_filter();
+#include <stddef.h>
+#include <linux/seccomp.h>
+
+extern const struct sock_filter arm_filter[];
+extern const size_t arm_filter_size;
+extern const struct sock_filter arm64_filter[];
+extern const size_t arm64_filter_size;
#endif
#include <linux/filter.h>
#include <errno.h>
- #include "seccomp_bpfs.h"
- const sock_filter {architecture}_filter[] = {{
+ #include "seccomp_policy.h"
+ const struct sock_filter {architecture}_filter[] = {{
""").format(architecture=architecture)
footer = textwrap.dedent("""\
# And output policy
existing = ""
- output_path = "seccomp/{}_policy.cpp".format(arch)
+ output_path = "seccomp/{}_policy.c".format(arch)
if os.path.isfile(output_path):
existing = open(output_path).read()
if output == existing:
#include <linux/filter.h>
#include <errno.h>
- #include "seccomp_bpfs.h"
- const sock_filter arm_filter[] = {
+ #include "seccomp_policy.h"
+ const struct sock_filter arm_filter[] = {
line1
line2
};
#include <linux/filter.h>
#include <errno.h>
- #include "seccomp_bpfs.h"
- const sock_filter arm_filter[] = {
+ #include "seccomp_policy.h"
+ const struct sock_filter arm_filter[] = {
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 3, 0, 3),
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 140, 1, 0),
BPF_JUMP(BPF_JMP|BPF_JGE|BPF_K, 4, 2, 1), //read