1 // Copyright (c) 2012 The Chromium Authors. All rights reserved. 2 // Use of this source code is governed by a BSD-style license that can be 3 // found in the LICENSE file. 4 5 #ifndef SANDBOX_LINUX_SECCOMP_BPF_LINUX_SECCOMP_H__ 6 #define SANDBOX_LINUX_SECCOMP_BPF_LINUX_SECCOMP_H__ 7 8 // The Seccomp2 kernel ABI is not part of older versions of glibc. 9 // As we can't break compilation with these versions of the library, 10 // we explicitly define all missing symbols. 11 // If we ever decide that we can now rely on system headers, the following 12 // include files should be enabled: 13 // #include <linux/audit.h> 14 // #include <linux/seccomp.h> 15 16 #include <asm/unistd.h> 17 #include <linux/filter.h> 18 19 // For audit.h 20 #ifndef EM_ARM 21 #define EM_ARM 40 22 #endif 23 #ifndef EM_386 24 #define EM_386 3 25 #endif 26 #ifndef EM_X86_64 27 #define EM_X86_64 62 28 #endif 29 30 #ifndef __AUDIT_ARCH_64BIT 31 #define __AUDIT_ARCH_64BIT 0x80000000 32 #endif 33 #ifndef __AUDIT_ARCH_LE 34 #define __AUDIT_ARCH_LE 0x40000000 35 #endif 36 #ifndef AUDIT_ARCH_ARM 37 #define AUDIT_ARCH_ARM (EM_ARM|__AUDIT_ARCH_LE) 38 #endif 39 #ifndef AUDIT_ARCH_I386 40 #define AUDIT_ARCH_I386 (EM_386|__AUDIT_ARCH_LE) 41 #endif 42 #ifndef AUDIT_ARCH_X86_64 43 #define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE) 44 #endif 45 46 // For prctl.h 47 #ifndef PR_SET_SECCOMP 48 #define PR_SET_SECCOMP 22 49 #define PR_GET_SECCOMP 21 50 #endif 51 #ifndef PR_SET_NO_NEW_PRIVS 52 #define PR_SET_NO_NEW_PRIVS 38 53 #define PR_GET_NO_NEW_PRIVS 39 54 #endif 55 #ifndef IPC_64 56 #define IPC_64 0x0100 57 #endif 58 59 #ifndef BPF_MOD 60 #define BPF_MOD 0x90 61 #endif 62 #ifndef BPF_XOR 63 #define BPF_XOR 0xA0 64 #endif 65 66 // In order to build will older tool chains, we currently have to avoid 67 // including <linux/seccomp.h>. Until that can be fixed (if ever). Rely on 68 // our own definitions of the seccomp kernel ABI. 69 #ifndef SECCOMP_MODE_FILTER 70 #define SECCOMP_MODE_DISABLED 0 71 #define SECCOMP_MODE_STRICT 1 72 #define SECCOMP_MODE_FILTER 2 // User user-supplied filter 73 #endif 74 75 #ifndef SECCOMP_RET_KILL 76 // Return values supported for BPF filter programs. Please note that the 77 // "illegal" SECCOMP_RET_INVALID is not supported by the kernel, should only 78 // ever be used internally, and would result in the kernel killing our process. 79 #define SECCOMP_RET_KILL 0x00000000U // Kill the task immediately 80 #define SECCOMP_RET_INVALID 0x00010000U // Illegal return value 81 #define SECCOMP_RET_TRAP 0x00030000U // Disallow and force a SIGSYS 82 #define SECCOMP_RET_ERRNO 0x00050000U // Returns an errno 83 #define SECCOMP_RET_TRACE 0x7ff00000U // Pass to a tracer or disallow 84 #define SECCOMP_RET_ALLOW 0x7fff0000U // Allow 85 #define SECCOMP_RET_ACTION 0xffff0000U // Masks for the return value 86 #define SECCOMP_RET_DATA 0x0000ffffU // sections 87 #else 88 #define SECCOMP_RET_INVALID 0x00010000U // Illegal return value 89 #endif 90 91 #ifndef SYS_SECCOMP 92 #define SYS_SECCOMP 1 93 #endif 94 95 // Impose some reasonable maximum BPF program size. Realistically, the 96 // kernel probably has much lower limits. But by limiting to less than 97 // 30 bits, we can ease requirements on some of our data types. 98 #define SECCOMP_MAX_PROGRAM_SIZE (1<<30) 99 100 #if defined(__i386__) 101 #define MIN_SYSCALL 0u 102 #define MAX_PUBLIC_SYSCALL 1024u 103 #define MAX_SYSCALL MAX_PUBLIC_SYSCALL 104 #define SECCOMP_ARCH AUDIT_ARCH_I386 105 106 #define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.gregs[(_reg)]) 107 #define SECCOMP_RESULT(_ctx) SECCOMP_REG(_ctx, REG_EAX) 108 #define SECCOMP_SYSCALL(_ctx) SECCOMP_REG(_ctx, REG_EAX) 109 #define SECCOMP_IP(_ctx) SECCOMP_REG(_ctx, REG_EIP) 110 #define SECCOMP_PARM1(_ctx) SECCOMP_REG(_ctx, REG_EBX) 111 #define SECCOMP_PARM2(_ctx) SECCOMP_REG(_ctx, REG_ECX) 112 #define SECCOMP_PARM3(_ctx) SECCOMP_REG(_ctx, REG_EDX) 113 #define SECCOMP_PARM4(_ctx) SECCOMP_REG(_ctx, REG_ESI) 114 #define SECCOMP_PARM5(_ctx) SECCOMP_REG(_ctx, REG_EDI) 115 #define SECCOMP_PARM6(_ctx) SECCOMP_REG(_ctx, REG_EBP) 116 #define SECCOMP_NR_IDX (offsetof(struct arch_seccomp_data, nr)) 117 #define SECCOMP_ARCH_IDX (offsetof(struct arch_seccomp_data, arch)) 118 #define SECCOMP_IP_MSB_IDX (offsetof(struct arch_seccomp_data, \ 119 instruction_pointer) + 4) 120 #define SECCOMP_IP_LSB_IDX (offsetof(struct arch_seccomp_data, \ 121 instruction_pointer) + 0) 122 #define SECCOMP_ARG_MSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) + \ 123 8*(nr) + 4) 124 #define SECCOMP_ARG_LSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) + \ 125 8*(nr) + 0) 126 127 #elif defined(__x86_64__) 128 #define MIN_SYSCALL 0u 129 #define MAX_PUBLIC_SYSCALL 1024u 130 #define MAX_SYSCALL MAX_PUBLIC_SYSCALL 131 #define SECCOMP_ARCH AUDIT_ARCH_X86_64 132 133 #define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.gregs[(_reg)]) 134 #define SECCOMP_RESULT(_ctx) SECCOMP_REG(_ctx, REG_RAX) 135 #define SECCOMP_SYSCALL(_ctx) SECCOMP_REG(_ctx, REG_RAX) 136 #define SECCOMP_IP(_ctx) SECCOMP_REG(_ctx, REG_RIP) 137 #define SECCOMP_PARM1(_ctx) SECCOMP_REG(_ctx, REG_RDI) 138 #define SECCOMP_PARM2(_ctx) SECCOMP_REG(_ctx, REG_RSI) 139 #define SECCOMP_PARM3(_ctx) SECCOMP_REG(_ctx, REG_RDX) 140 #define SECCOMP_PARM4(_ctx) SECCOMP_REG(_ctx, REG_R10) 141 #define SECCOMP_PARM5(_ctx) SECCOMP_REG(_ctx, REG_R8) 142 #define SECCOMP_PARM6(_ctx) SECCOMP_REG(_ctx, REG_R9) 143 #define SECCOMP_NR_IDX (offsetof(struct arch_seccomp_data, nr)) 144 #define SECCOMP_ARCH_IDX (offsetof(struct arch_seccomp_data, arch)) 145 #define SECCOMP_IP_MSB_IDX (offsetof(struct arch_seccomp_data, \ 146 instruction_pointer) + 4) 147 #define SECCOMP_IP_LSB_IDX (offsetof(struct arch_seccomp_data, \ 148 instruction_pointer) + 0) 149 #define SECCOMP_ARG_MSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) + \ 150 8*(nr) + 4) 151 #define SECCOMP_ARG_LSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) + \ 152 8*(nr) + 0) 153 154 #elif defined(__arm__) && (defined(__thumb__) || defined(__ARM_EABI__)) 155 // ARM EABI includes "ARM private" system calls starting at |__ARM_NR_BASE|, 156 // and a "ghost syscall private to the kernel", cmpxchg, 157 // at |__ARM_NR_BASE+0x00fff0|. 158 // See </arch/arm/include/asm/unistd.h> in the Linux kernel. 159 #define MIN_SYSCALL ((unsigned int)__NR_SYSCALL_BASE) 160 #define MAX_PUBLIC_SYSCALL (MIN_SYSCALL + 1024u) 161 #define MIN_PRIVATE_SYSCALL ((unsigned int)__ARM_NR_BASE) 162 #define MAX_PRIVATE_SYSCALL (MIN_PRIVATE_SYSCALL + 16u) 163 #define MIN_GHOST_SYSCALL ((unsigned int)__ARM_NR_BASE + 0xfff0u) 164 #define MAX_SYSCALL (MIN_GHOST_SYSCALL + 4u) 165 166 #define SECCOMP_ARCH AUDIT_ARCH_ARM 167 168 // ARM sigcontext_t is different from i386/x86_64. 169 // See </arch/arm/include/asm/sigcontext.h> in the Linux kernel. 170 #define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.arm_##_reg) 171 // ARM EABI syscall convention. 172 #define SECCOMP_RESULT(_ctx) SECCOMP_REG(_ctx, r0) 173 #define SECCOMP_SYSCALL(_ctx) SECCOMP_REG(_ctx, r7) 174 #define SECCOMP_IP(_ctx) SECCOMP_REG(_ctx, pc) 175 #define SECCOMP_PARM1(_ctx) SECCOMP_REG(_ctx, r0) 176 #define SECCOMP_PARM2(_ctx) SECCOMP_REG(_ctx, r1) 177 #define SECCOMP_PARM3(_ctx) SECCOMP_REG(_ctx, r2) 178 #define SECCOMP_PARM4(_ctx) SECCOMP_REG(_ctx, r3) 179 #define SECCOMP_PARM5(_ctx) SECCOMP_REG(_ctx, r4) 180 #define SECCOMP_PARM6(_ctx) SECCOMP_REG(_ctx, r5) 181 #define SECCOMP_NR_IDX (offsetof(struct arch_seccomp_data, nr)) 182 #define SECCOMP_ARCH_IDX (offsetof(struct arch_seccomp_data, arch)) 183 #define SECCOMP_IP_MSB_IDX (offsetof(struct arch_seccomp_data, \ 184 instruction_pointer) + 4) 185 #define SECCOMP_IP_LSB_IDX (offsetof(struct arch_seccomp_data, \ 186 instruction_pointer) + 0) 187 #define SECCOMP_ARG_MSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) + \ 188 8*(nr) + 4) 189 #define SECCOMP_ARG_LSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) + \ 190 8*(nr) + 0) 191 192 #else 193 #error Unsupported target platform 194 195 #endif 196 197 #endif // SANDBOX_LINUX_SECCOMP_BPF_LINUX_SECCOMP_H__ 198
