libseccomp/src/arch.h

   1 /**
   2  * Enhanced Seccomp Architecture/Machine Specific Code
   3  *
   4  * Copyright (c) 2012 Red Hat <pmoore@redhat.com>
   5  * Author: Paul Moore <paul@paul-moore.com>
   6  */
   7
   8 /*
   9  * This library is free software; you can redistribute it and/or modify it
  10  * under the terms of version 2.1 of the GNU Lesser General Public License as
  11  * published by the Free Software Foundation.
  12  *
  13  * This library is distributed in the hope that it will be useful, but WITHOUT
  14  * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
  15  * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU Lesser General Public License
  16  * for more details.
  17  *
  18  * You should have received a copy of the GNU Lesser General Public License
  19  * along with this library; if not, see <http://www.gnu.org/licenses>.
  20  */
  21
  22 #ifndef _ARCH_H
  23 #define _ARCH_H
  24
  25 #include <inttypes.h>
  26 #include <stddef.h>
  27 #include <stdbool.h>
  28
  29 #include <seccomp.h>
  30
  31 #include "system.h"
  32
  33 struct db_filter;
  34 struct db_api_arg;
  35 struct db_api_rule_list;
  36
  37 struct arch_def {
  38         /* arch definition */
  39         uint32_t token;
  40         uint32_t token_bpf;
  41         enum {
  42                 ARCH_SIZE_UNSPEC = 0,
  43                 ARCH_SIZE_32 = 32,
  44                 ARCH_SIZE_64 = 64,
  45         } size;
  46         enum {
  47                 ARCH_ENDIAN_UNSPEC = 0,
  48                 ARCH_ENDIAN_LITTLE,
  49                 ARCH_ENDIAN_BIG,
  50         } endian;
  51
  52         /* arch specific functions */
  53         int (*syscall_resolve_name)(const char *name);
  54         const char *(*syscall_resolve_num)(int num);
  55         int (*syscall_rewrite)(int *syscall);
  56         int (*rule_add)(struct db_filter_col *col, struct db_filter *db,
  57                         bool strict, struct db_api_rule_list *rule);
  58 };
  59
  60 /* arch_def for the current architecture */
  61 extern const struct arch_def *arch_def_native;
  62
  63 /* NOTE: Syscall mappings can be found by running the following commands
  64  *       on the specific architecture's include file:
  65  *         # gcc -E -dM <file> | grep '__NR_'
  66  *       where <file> in many cases is /usr/include/asm/unistd.h, however,
  67  *       depending on the architecture you may need to use a different header.
  68  *       Further, you can automatically format this list for use as a struct
  69  *       initializer with the following command:
  70  *         # gcc -E -dM <file> | grep '__NR_' | \
  71  *           sed -e 's/#define[ \t]\+__NR_//' | sort | \
  72  *           sed -e 's/\([^ \t]\+\)\([ \t]\+\)\([0-9]\+\)/\t{ \"\1\", \3 },/'
  73  *       Finally, when creating a table/array of this structure, the final
  74  *       sentinel entry should be "{ NULL, __NR_SCMP_ERROR }"; see the existing
  75  *       tables as an example.
  76  */
  77 struct arch_syscall_def {
  78         const char *name;
  79         unsigned int num;
  80 };
  81
  82 #define DATUM_MAX       ((scmp_datum_t)-1)
  83 #define D64_LO(x)       ((uint32_t)((uint64_t)(x) & 0x00000000ffffffff))
  84 #define D64_HI(x)       ((uint32_t)((uint64_t)(x) >> 32))
  85
  86 #define ARG_COUNT_MAX   6
  87
  88 int arch_valid(uint32_t arch);
  89
  90 const struct arch_def *arch_def_lookup(uint32_t token);
  91 const struct arch_def *arch_def_lookup_name(const char *arch_name);
  92
  93 int arch_arg_count_max(const struct arch_def *arch);
  94
  95 int arch_arg_offset_lo(const struct arch_def *arch, unsigned int arg);
  96 int arch_arg_offset_hi(const struct arch_def *arch, unsigned int arg);
  97 int arch_arg_offset(const struct arch_def *arch, unsigned int arg);
  98
  99 int arch_syscall_resolve_name(const struct arch_def *arch, const char *name);
 100 const char *arch_syscall_resolve_num(const struct arch_def *arch, int num);
 101
 102 int arch_syscall_translate(const struct arch_def *arch, int *syscall);
 103 int arch_syscall_rewrite(const struct arch_def *arch, int *syscall);
 104
 105 int arch_filter_rule_add(struct db_filter_col *col, struct db_filter *db,
 106                          bool strict, uint32_t action, int syscall,
 107                          unsigned int chain_len, struct db_api_arg *chain);
 108
 109 #endif