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#include <sys/cdefs.h>
20// Old Bionic versions do not have sys/user.h.  The if can be removed once we no
21// longer need to support these old Bionic versions.
22// All x86_64 builds use a new enough bionic to have sys/user.h.
23#if !defined(__BIONIC__) || defined(__x86_64__)
24#include <sys/types.h>  // Fix for gcc 4.7, make sure __uint16_t is defined.
25#include <sys/user.h>
26#if defined(__mips__)
27// sys/user.h in eglibc misses size_t definition
28#include <stddef.h>
29#endif
30#endif
31
32// For audit.h
33#ifndef EM_ARM
34#define EM_ARM    40
35#endif
36#ifndef EM_386
37#define EM_386    3
38#endif
39#ifndef EM_X86_64
40#define EM_X86_64 62
41#endif
42#ifndef EM_MIPS
43#define EM_MIPS   8
44#endif
45#ifndef EM_AARCH64
46#define EM_AARCH64 183
47#endif
48
49#ifndef __AUDIT_ARCH_64BIT
50#define __AUDIT_ARCH_64BIT 0x80000000
51#endif
52#ifndef __AUDIT_ARCH_LE
53#define __AUDIT_ARCH_LE    0x40000000
54#endif
55#ifndef AUDIT_ARCH_ARM
56#define AUDIT_ARCH_ARM    (EM_ARM|__AUDIT_ARCH_LE)
57#endif
58#ifndef AUDIT_ARCH_I386
59#define AUDIT_ARCH_I386   (EM_386|__AUDIT_ARCH_LE)
60#endif
61#ifndef AUDIT_ARCH_X86_64
62#define AUDIT_ARCH_X86_64 (EM_X86_64|__AUDIT_ARCH_64BIT|__AUDIT_ARCH_LE)
63#endif
64#ifndef AUDIT_ARCH_MIPSEL
65#define AUDIT_ARCH_MIPSEL (EM_MIPS|__AUDIT_ARCH_LE)
66#endif
67#ifndef AUDIT_ARCH_AARCH64
68#define AUDIT_ARCH_AARCH64 (EM_AARCH64 | __AUDIT_ARCH_64BIT | __AUDIT_ARCH_LE)
69#endif
70
71// For prctl.h
72#ifndef PR_SET_SECCOMP
73#define PR_SET_SECCOMP               22
74#define PR_GET_SECCOMP               21
75#endif
76#ifndef PR_SET_NO_NEW_PRIVS
77#define PR_SET_NO_NEW_PRIVS          38
78#define PR_GET_NO_NEW_PRIVS          39
79#endif
80#ifndef IPC_64
81#define IPC_64                   0x0100
82#endif
83
84#ifndef BPF_MOD
85#define BPF_MOD                    0x90
86#endif
87#ifndef BPF_XOR
88#define BPF_XOR                    0xA0
89#endif
90
91// In order to build will older tool chains, we currently have to avoid
92// including <linux/seccomp.h>. Until that can be fixed (if ever). Rely on
93// our own definitions of the seccomp kernel ABI.
94#ifndef SECCOMP_MODE_FILTER
95#define SECCOMP_MODE_DISABLED         0
96#define SECCOMP_MODE_STRICT           1
97#define SECCOMP_MODE_FILTER           2  // User user-supplied filter
98#endif
99
100#ifndef SECCOMP_SET_MODE_STRICT
101#define SECCOMP_SET_MODE_STRICT 0
102#endif
103#ifndef SECCOMP_SET_MODE_FILTER
104#define SECCOMP_SET_MODE_FILTER 1
105#endif
106#ifndef SECCOMP_FILTER_FLAG_TSYNC
107#define SECCOMP_FILTER_FLAG_TSYNC 1
108#endif
109
110#ifndef SECCOMP_RET_KILL
111// Return values supported for BPF filter programs. Please note that the
112// "illegal" SECCOMP_RET_INVALID is not supported by the kernel, should only
113// ever be used internally, and would result in the kernel killing our process.
114#define SECCOMP_RET_KILL    0x00000000U  // Kill the task immediately
115#define SECCOMP_RET_INVALID 0x00010000U  // Illegal return value
116#define SECCOMP_RET_TRAP    0x00030000U  // Disallow and force a SIGSYS
117#define SECCOMP_RET_ERRNO   0x00050000U  // Returns an errno
118#define SECCOMP_RET_TRACE   0x7ff00000U  // Pass to a tracer or disallow
119#define SECCOMP_RET_ALLOW   0x7fff0000U  // Allow
120#define SECCOMP_RET_ACTION  0xffff0000U  // Masks for the return value
121#define SECCOMP_RET_DATA    0x0000ffffU  //   sections
122#else
123#define SECCOMP_RET_INVALID 0x00010000U  // Illegal return value
124#endif
125
126#ifndef SYS_SECCOMP
127#define SYS_SECCOMP                   1
128#endif
129
130// Impose some reasonable maximum BPF program size. Realistically, the
131// kernel probably has much lower limits. But by limiting to less than
132// 30 bits, we can ease requirements on some of our data types.
133#define SECCOMP_MAX_PROGRAM_SIZE (1<<30)
134
135#if defined(__i386__)
136#define MIN_SYSCALL         0u
137#define MAX_PUBLIC_SYSCALL  1024u
138#define MAX_SYSCALL         MAX_PUBLIC_SYSCALL
139#define SECCOMP_ARCH        AUDIT_ARCH_I386
140
141#define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.gregs[(_reg)])
142#define SECCOMP_RESULT(_ctx)    SECCOMP_REG(_ctx, REG_EAX)
143#define SECCOMP_SYSCALL(_ctx)   SECCOMP_REG(_ctx, REG_EAX)
144#define SECCOMP_IP(_ctx)        SECCOMP_REG(_ctx, REG_EIP)
145#define SECCOMP_PARM1(_ctx)     SECCOMP_REG(_ctx, REG_EBX)
146#define SECCOMP_PARM2(_ctx)     SECCOMP_REG(_ctx, REG_ECX)
147#define SECCOMP_PARM3(_ctx)     SECCOMP_REG(_ctx, REG_EDX)
148#define SECCOMP_PARM4(_ctx)     SECCOMP_REG(_ctx, REG_ESI)
149#define SECCOMP_PARM5(_ctx)     SECCOMP_REG(_ctx, REG_EDI)
150#define SECCOMP_PARM6(_ctx)     SECCOMP_REG(_ctx, REG_EBP)
151#define SECCOMP_NR_IDX          (offsetof(struct arch_seccomp_data, nr))
152#define SECCOMP_ARCH_IDX        (offsetof(struct arch_seccomp_data, arch))
153#define SECCOMP_IP_MSB_IDX      (offsetof(struct arch_seccomp_data,           \
154                                          instruction_pointer) + 4)
155#define SECCOMP_IP_LSB_IDX      (offsetof(struct arch_seccomp_data,           \
156                                          instruction_pointer) + 0)
157#define SECCOMP_ARG_MSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
158                                 8*(nr) + 4)
159#define SECCOMP_ARG_LSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
160                                 8*(nr) + 0)
161
162
163#if defined(__BIONIC__)
164// Old Bionic versions don't have sys/user.h, so we just define regs_struct
165// directly.  This can be removed once we no longer need to support these old
166// Bionic versions.
167struct regs_struct {
168  long int ebx;
169  long int ecx;
170  long int edx;
171  long int esi;
172  long int edi;
173  long int ebp;
174  long int eax;
175  long int xds;
176  long int xes;
177  long int xfs;
178  long int xgs;
179  long int orig_eax;
180  long int eip;
181  long int xcs;
182  long int eflags;
183  long int esp;
184  long int xss;
185};
186#else
187typedef user_regs_struct regs_struct;
188#endif
189
190#define SECCOMP_PT_RESULT(_regs)  (_regs).eax
191#define SECCOMP_PT_SYSCALL(_regs) (_regs).orig_eax
192#define SECCOMP_PT_IP(_regs)      (_regs).eip
193#define SECCOMP_PT_PARM1(_regs)   (_regs).ebx
194#define SECCOMP_PT_PARM2(_regs)   (_regs).ecx
195#define SECCOMP_PT_PARM3(_regs)   (_regs).edx
196#define SECCOMP_PT_PARM4(_regs)   (_regs).esi
197#define SECCOMP_PT_PARM5(_regs)   (_regs).edi
198#define SECCOMP_PT_PARM6(_regs)   (_regs).ebp
199
200#elif defined(__x86_64__)
201#define MIN_SYSCALL         0u
202#define MAX_PUBLIC_SYSCALL  1024u
203#define MAX_SYSCALL         MAX_PUBLIC_SYSCALL
204#define SECCOMP_ARCH        AUDIT_ARCH_X86_64
205
206#define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.gregs[(_reg)])
207#define SECCOMP_RESULT(_ctx)    SECCOMP_REG(_ctx, REG_RAX)
208#define SECCOMP_SYSCALL(_ctx)   SECCOMP_REG(_ctx, REG_RAX)
209#define SECCOMP_IP(_ctx)        SECCOMP_REG(_ctx, REG_RIP)
210#define SECCOMP_PARM1(_ctx)     SECCOMP_REG(_ctx, REG_RDI)
211#define SECCOMP_PARM2(_ctx)     SECCOMP_REG(_ctx, REG_RSI)
212#define SECCOMP_PARM3(_ctx)     SECCOMP_REG(_ctx, REG_RDX)
213#define SECCOMP_PARM4(_ctx)     SECCOMP_REG(_ctx, REG_R10)
214#define SECCOMP_PARM5(_ctx)     SECCOMP_REG(_ctx, REG_R8)
215#define SECCOMP_PARM6(_ctx)     SECCOMP_REG(_ctx, REG_R9)
216#define SECCOMP_NR_IDX          (offsetof(struct arch_seccomp_data, nr))
217#define SECCOMP_ARCH_IDX        (offsetof(struct arch_seccomp_data, arch))
218#define SECCOMP_IP_MSB_IDX      (offsetof(struct arch_seccomp_data,           \
219                                          instruction_pointer) + 4)
220#define SECCOMP_IP_LSB_IDX      (offsetof(struct arch_seccomp_data,           \
221                                          instruction_pointer) + 0)
222#define SECCOMP_ARG_MSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
223                                 8*(nr) + 4)
224#define SECCOMP_ARG_LSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
225                                 8*(nr) + 0)
226
227typedef user_regs_struct regs_struct;
228#define SECCOMP_PT_RESULT(_regs)  (_regs).rax
229#define SECCOMP_PT_SYSCALL(_regs) (_regs).orig_rax
230#define SECCOMP_PT_IP(_regs)      (_regs).rip
231#define SECCOMP_PT_PARM1(_regs)   (_regs).rdi
232#define SECCOMP_PT_PARM2(_regs)   (_regs).rsi
233#define SECCOMP_PT_PARM3(_regs)   (_regs).rdx
234#define SECCOMP_PT_PARM4(_regs)   (_regs).r10
235#define SECCOMP_PT_PARM5(_regs)   (_regs).r8
236#define SECCOMP_PT_PARM6(_regs)   (_regs).r9
237
238#elif defined(__arm__) && (defined(__thumb__) || defined(__ARM_EABI__))
239// ARM EABI includes "ARM private" system calls starting at |__ARM_NR_BASE|,
240// and a "ghost syscall private to the kernel", cmpxchg,
241// at |__ARM_NR_BASE+0x00fff0|.
242// See </arch/arm/include/asm/unistd.h> in the Linux kernel.
243#define MIN_SYSCALL         ((unsigned int)__NR_SYSCALL_BASE)
244#define MAX_PUBLIC_SYSCALL  (MIN_SYSCALL + 1024u)
245#define MIN_PRIVATE_SYSCALL ((unsigned int)__ARM_NR_BASE)
246#define MAX_PRIVATE_SYSCALL (MIN_PRIVATE_SYSCALL + 16u)
247#define MIN_GHOST_SYSCALL   ((unsigned int)__ARM_NR_BASE + 0xfff0u)
248#define MAX_SYSCALL         (MIN_GHOST_SYSCALL + 4u)
249
250#define SECCOMP_ARCH AUDIT_ARCH_ARM
251
252// ARM sigcontext_t is different from i386/x86_64.
253// See </arch/arm/include/asm/sigcontext.h> in the Linux kernel.
254#define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.arm_##_reg)
255// ARM EABI syscall convention.
256#define SECCOMP_RESULT(_ctx)    SECCOMP_REG(_ctx, r0)
257#define SECCOMP_SYSCALL(_ctx)   SECCOMP_REG(_ctx, r7)
258#define SECCOMP_IP(_ctx)        SECCOMP_REG(_ctx, pc)
259#define SECCOMP_PARM1(_ctx)     SECCOMP_REG(_ctx, r0)
260#define SECCOMP_PARM2(_ctx)     SECCOMP_REG(_ctx, r1)
261#define SECCOMP_PARM3(_ctx)     SECCOMP_REG(_ctx, r2)
262#define SECCOMP_PARM4(_ctx)     SECCOMP_REG(_ctx, r3)
263#define SECCOMP_PARM5(_ctx)     SECCOMP_REG(_ctx, r4)
264#define SECCOMP_PARM6(_ctx)     SECCOMP_REG(_ctx, r5)
265#define SECCOMP_NR_IDX          (offsetof(struct arch_seccomp_data, nr))
266#define SECCOMP_ARCH_IDX        (offsetof(struct arch_seccomp_data, arch))
267#define SECCOMP_IP_MSB_IDX      (offsetof(struct arch_seccomp_data,           \
268                                          instruction_pointer) + 4)
269#define SECCOMP_IP_LSB_IDX      (offsetof(struct arch_seccomp_data,           \
270                                          instruction_pointer) + 0)
271#define SECCOMP_ARG_MSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
272                                 8*(nr) + 4)
273#define SECCOMP_ARG_LSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
274                                 8*(nr) + 0)
275
276#if defined(__BIONIC__)
277// Old Bionic versions don't have sys/user.h, so we just define regs_struct
278// directly.  This can be removed once we no longer need to support these old
279// Bionic versions.
280struct regs_struct {
281  unsigned long uregs[18];
282};
283#else
284typedef user_regs regs_struct;
285#endif
286
287#define REG_cpsr    uregs[16]
288#define REG_pc      uregs[15]
289#define REG_lr      uregs[14]
290#define REG_sp      uregs[13]
291#define REG_ip      uregs[12]
292#define REG_fp      uregs[11]
293#define REG_r10     uregs[10]
294#define REG_r9      uregs[9]
295#define REG_r8      uregs[8]
296#define REG_r7      uregs[7]
297#define REG_r6      uregs[6]
298#define REG_r5      uregs[5]
299#define REG_r4      uregs[4]
300#define REG_r3      uregs[3]
301#define REG_r2      uregs[2]
302#define REG_r1      uregs[1]
303#define REG_r0      uregs[0]
304#define REG_ORIG_r0 uregs[17]
305
306#define SECCOMP_PT_RESULT(_regs)  (_regs).REG_r0
307#define SECCOMP_PT_SYSCALL(_regs) (_regs).REG_r7
308#define SECCOMP_PT_IP(_regs)      (_regs).REG_pc
309#define SECCOMP_PT_PARM1(_regs)   (_regs).REG_r0
310#define SECCOMP_PT_PARM2(_regs)   (_regs).REG_r1
311#define SECCOMP_PT_PARM3(_regs)   (_regs).REG_r2
312#define SECCOMP_PT_PARM4(_regs)   (_regs).REG_r3
313#define SECCOMP_PT_PARM5(_regs)   (_regs).REG_r4
314#define SECCOMP_PT_PARM6(_regs)   (_regs).REG_r5
315
316#elif defined(__mips__) && (_MIPS_SIM == _MIPS_SIM_ABI32)
317#define MIN_SYSCALL         __NR_O32_Linux
318#define MAX_PUBLIC_SYSCALL  (MIN_SYSCALL + __NR_Linux_syscalls)
319#define MAX_SYSCALL         MAX_PUBLIC_SYSCALL
320#define SECCOMP_ARCH        AUDIT_ARCH_MIPSEL
321#define SYSCALL_EIGHT_ARGS
322// MIPS sigcontext_t is different from i386/x86_64 and ARM.
323// See </arch/mips/include/uapi/asm/sigcontext.h> in the Linux kernel.
324#define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.gregs[_reg])
325// Based on MIPS o32 ABI syscall convention.
326// On MIPS, when indirect syscall is being made (syscall(__NR_foo)),
327// real identificator (__NR_foo) is not in v0, but in a0
328#define SECCOMP_RESULT(_ctx)    SECCOMP_REG(_ctx, 2)
329#define SECCOMP_SYSCALL(_ctx)   SECCOMP_REG(_ctx, 2)
330#define SECCOMP_IP(_ctx)        (_ctx)->uc_mcontext.pc
331#define SECCOMP_PARM1(_ctx)     SECCOMP_REG(_ctx, 4)
332#define SECCOMP_PARM2(_ctx)     SECCOMP_REG(_ctx, 5)
333#define SECCOMP_PARM3(_ctx)     SECCOMP_REG(_ctx, 6)
334#define SECCOMP_PARM4(_ctx)     SECCOMP_REG(_ctx, 7)
335// Only the first 4 arguments of syscall are in registers.
336// The rest are on the stack.
337#define SECCOMP_STACKPARM(_ctx, n)  (((long *)SECCOMP_REG(_ctx, 29))[(n)])
338#define SECCOMP_PARM5(_ctx)         SECCOMP_STACKPARM(_ctx, 4)
339#define SECCOMP_PARM6(_ctx)         SECCOMP_STACKPARM(_ctx, 5)
340#define SECCOMP_PARM7(_ctx)         SECCOMP_STACKPARM(_ctx, 6)
341#define SECCOMP_PARM8(_ctx)         SECCOMP_STACKPARM(_ctx, 7)
342#define SECCOMP_NR_IDX          (offsetof(struct arch_seccomp_data, nr))
343#define SECCOMP_ARCH_IDX        (offsetof(struct arch_seccomp_data, arch))
344#define SECCOMP_IP_MSB_IDX      (offsetof(struct arch_seccomp_data,           \
345                                          instruction_pointer) + 4)
346#define SECCOMP_IP_LSB_IDX      (offsetof(struct arch_seccomp_data,           \
347                                          instruction_pointer) + 0)
348#define SECCOMP_ARG_MSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
349                                 8*(nr) + 4)
350#define SECCOMP_ARG_LSB_IDX(nr) (offsetof(struct arch_seccomp_data, args) +   \
351                                 8*(nr) + 0)
352
353// On Mips we don't have structures like user_regs or user_regs_struct in
354// sys/user.h that we could use, so we just define regs_struct directly.
355struct regs_struct {
356  unsigned long long regs[32];
357};
358
359#define REG_a3 regs[7]
360#define REG_a2 regs[6]
361#define REG_a1 regs[5]
362#define REG_a0 regs[4]
363#define REG_v1 regs[3]
364#define REG_v0 regs[2]
365
366#define SECCOMP_PT_RESULT(_regs)  (_regs).REG_v0
367#define SECCOMP_PT_SYSCALL(_regs) (_regs).REG_v0
368#define SECCOMP_PT_PARM1(_regs)   (_regs).REG_a0
369#define SECCOMP_PT_PARM2(_regs)   (_regs).REG_a1
370#define SECCOMP_PT_PARM3(_regs)   (_regs).REG_a2
371#define SECCOMP_PT_PARM4(_regs)   (_regs).REG_a3
372
373#elif defined(__aarch64__)
374struct regs_struct {
375  unsigned long long regs[31];
376  unsigned long long sp;
377  unsigned long long pc;
378  unsigned long long pstate;
379};
380
381#define MIN_SYSCALL 0u
382#define MAX_PUBLIC_SYSCALL 279u
383#define MAX_SYSCALL MAX_PUBLIC_SYSCALL
384#define SECCOMP_ARCH AUDIT_ARCH_AARCH64
385
386#define SECCOMP_REG(_ctx, _reg) ((_ctx)->uc_mcontext.regs[_reg])
387
388#define SECCOMP_RESULT(_ctx) SECCOMP_REG(_ctx, 0)
389#define SECCOMP_SYSCALL(_ctx) SECCOMP_REG(_ctx, 8)
390#define SECCOMP_IP(_ctx) (_ctx)->uc_mcontext.pc
391#define SECCOMP_PARM1(_ctx) SECCOMP_REG(_ctx, 0)
392#define SECCOMP_PARM2(_ctx) SECCOMP_REG(_ctx, 1)
393#define SECCOMP_PARM3(_ctx) SECCOMP_REG(_ctx, 2)
394#define SECCOMP_PARM4(_ctx) SECCOMP_REG(_ctx, 3)
395#define SECCOMP_PARM5(_ctx) SECCOMP_REG(_ctx, 4)
396#define SECCOMP_PARM6(_ctx) SECCOMP_REG(_ctx, 5)
397
398#define SECCOMP_NR_IDX (offsetof(struct arch_seccomp_data, nr))
399#define SECCOMP_ARCH_IDX (offsetof(struct arch_seccomp_data, arch))
400#define SECCOMP_IP_MSB_IDX \
401  (offsetof(struct arch_seccomp_data, instruction_pointer) + 4)
402#define SECCOMP_IP_LSB_IDX \
403  (offsetof(struct arch_seccomp_data, instruction_pointer) + 0)
404#define SECCOMP_ARG_MSB_IDX(nr) \
405  (offsetof(struct arch_seccomp_data, args) + 8 * (nr) + 4)
406#define SECCOMP_ARG_LSB_IDX(nr) \
407  (offsetof(struct arch_seccomp_data, args) + 8 * (nr) + 0)
408
409#define SECCOMP_PT_RESULT(_regs) (_regs).regs[0]
410#define SECCOMP_PT_SYSCALL(_regs) (_regs).regs[8]
411#define SECCOMP_PT_IP(_regs) (_regs).pc
412#define SECCOMP_PT_PARM1(_regs) (_regs).regs[0]
413#define SECCOMP_PT_PARM2(_regs) (_regs).regs[1]
414#define SECCOMP_PT_PARM3(_regs) (_regs).regs[2]
415#define SECCOMP_PT_PARM4(_regs) (_regs).regs[3]
416#define SECCOMP_PT_PARM5(_regs) (_regs).regs[4]
417#define SECCOMP_PT_PARM6(_regs) (_regs).regs[5]
418#else
419#error Unsupported target platform
420
421#endif
422
423#endif  // SANDBOX_LINUX_SECCOMP_BPF_LINUX_SECCOMP_H__
424