src/lxc/syscall_wrappers.h

   1 /* liblxcapi
   2  *
   3  * Copyright © 2018 Christian Brauner <christian.brauner@ubuntu.com>.
   4  * Copyright © 2018 Canonical Ltd.
   5  *
   6  * This program is free software; you can redistribute it and/or modify
   7  * it under the terms of the GNU General Public License version 2, as
   8  * published by the Free Software Foundation.
   9  *
  10  * This program is distributed in the hope that it will be useful,
  11  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  12  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
  13  * GNU General Public License for more details.
  14  *
  15  * You should have received a copy of the GNU General Public License along
  16  * with this program; if not, write to the Free Software Foundation, Inc.,
  17  * 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
  18  */
  19
  20 #ifndef __LXC_SYSCALL_WRAPPER_H
  21 #define __LXC_SYSCALL_WRAPPER_H
  22
  23 #ifndef _GNU_SOURCE
  24 #define _GNU_SOURCE 1
  25 #endif
  26 #include <asm/unistd.h>
  27 #include <errno.h>
  28 #include <linux/keyctl.h>
  29 #include <sched.h>
  30 #include <stdint.h>
  31 #include <sys/syscall.h>
  32 #include <sys/types.h>
  33 #include <unistd.h>
  34
  35 #include "config.h"
  36
  37 #ifdef HAVE_LINUX_MEMFD_H
  38 #include <linux/memfd.h>
  39 #endif
  40
  41 #ifdef HAVE_SYS_SIGNALFD_H
  42 #include <sys/signalfd.h>
  43 #endif
  44
  45 typedef int32_t key_serial_t;
  46
  47 #if !HAVE_KEYCTL
  48 static inline long __keyctl(int cmd, unsigned long arg2, unsigned long arg3,
  49                             unsigned long arg4, unsigned long arg5)
  50 {
  51 #ifdef __NR_keyctl
  52         return syscall(__NR_keyctl, cmd, arg2, arg3, arg4, arg5);
  53 #else
  54         errno = ENOSYS;
  55         return -1;
  56 #endif
  57 }
  58 #define keyctl __keyctl
  59 #endif
  60
  61 #ifndef HAVE_MEMFD_CREATE
  62 static inline int memfd_create(const char *name, unsigned int flags) {
  63         #ifndef __NR_memfd_create
  64                 #if defined __i386__
  65                         #define __NR_memfd_create 356
  66                 #elif defined __x86_64__
  67                         #define __NR_memfd_create 319
  68                 #elif defined __arm__
  69                         #define __NR_memfd_create 385
  70                 #elif defined __aarch64__
  71                         #define __NR_memfd_create 279
  72                 #elif defined __s390__
  73                         #define __NR_memfd_create 350
  74                 #elif defined __powerpc__
  75                         #define __NR_memfd_create 360
  76                 #elif defined __sparc__
  77                         #define __NR_memfd_create 348
  78                 #elif defined __blackfin__
  79                         #define __NR_memfd_create 390
  80                 #elif defined __ia64__
  81                         #define __NR_memfd_create 1340
  82                 #elif defined _MIPS_SIM
  83                         #if _MIPS_SIM == _MIPS_SIM_ABI32
  84                                 #define __NR_memfd_create 4354
  85                         #endif
  86                         #if _MIPS_SIM == _MIPS_SIM_NABI32
  87                                 #define __NR_memfd_create 6318
  88                         #endif
  89                         #if _MIPS_SIM == _MIPS_SIM_ABI64
  90                                 #define __NR_memfd_create 5314
  91                         #endif
  92                 #endif
  93         #endif
  94         #ifdef __NR_memfd_create
  95         return syscall(__NR_memfd_create, name, flags);
  96         #else
  97         errno = ENOSYS;
  98         return -1;
  99         #endif
 100 }
 101 #else
 102 extern int memfd_create(const char *name, unsigned int flags);
 103 #endif
 104
 105 #if !HAVE_PIVOT_ROOT
 106 static int pivot_root(const char *new_root, const char *put_old)
 107 {
 108 #ifdef __NR_pivot_root
 109         return syscall(__NR_pivot_root, new_root, put_old);
 110 #else
 111         errno = ENOSYS;
 112         return -1;
 113 #endif
 114 }
 115 #else
 116 extern int pivot_root(const char *new_root, const char *put_old);
 117 #endif
 118
 119 #if !defined(__NR_setns) && !defined(__NR_set_ns)
 120         #if defined(__x86_64__)
 121                 #define __NR_setns 308
 122         #elif defined(__i386__)
 123                 #define __NR_setns 346
 124         #elif defined(__arm__)
 125                 #define __NR_setns 375
 126         #elif defined(__aarch64__)
 127                 #define __NR_setns 375
 128         #elif defined(__powerpc__)
 129                 #define __NR_setns 350
 130         #elif defined(__s390__)
 131                 #define __NR_setns 339
 132         #endif
 133 #endif
 134
 135 /* Define sethostname() if missing from the C library */
 136 #ifndef HAVE_SETHOSTNAME
 137 static inline int sethostname(const char *name, size_t len)
 138 {
 139 #ifdef __NR_sethostname
 140         return syscall(__NR_sethostname, name, len);
 141 #else
 142         errno = ENOSYS;
 143         return -1;
 144 #endif
 145 }
 146 #endif
 147
 148 /* Define setns() if missing from the C library */
 149 #ifndef HAVE_SETNS
 150 static inline int setns(int fd, int nstype)
 151 {
 152 #ifdef __NR_setns
 153         return syscall(__NR_setns, fd, nstype);
 154 #elif defined(__NR_set_ns)
 155         return syscall(__NR_set_ns, fd, nstype);
 156 #else
 157         errno = ENOSYS;
 158         return -1;
 159 #endif
 160 }
 161 #endif
 162
 163 #ifndef HAVE_SYS_SIGNALFD_H
 164 struct signalfd_siginfo {
 165         uint32_t ssi_signo;
 166         int32_t ssi_errno;
 167         int32_t ssi_code;
 168         uint32_t ssi_pid;
 169         uint32_t ssi_uid;
 170         int32_t ssi_fd;
 171         uint32_t ssi_tid;
 172         uint32_t ssi_band;
 173         uint32_t ssi_overrun;
 174         uint32_t ssi_trapno;
 175         int32_t ssi_status;
 176         int32_t ssi_int;
 177         uint64_t ssi_ptr;
 178         uint64_t ssi_utime;
 179         uint64_t ssi_stime;
 180         uint64_t ssi_addr;
 181         uint8_t __pad[48];
 182 };
 183
 184 #ifndef __NR_signalfd4
 185 /* assume kernel headers are too old */
 186 #if __i386__
 187 #define __NR_signalfd4 327
 188 #elif __x86_64__
 189 #define __NR_signalfd4 289
 190 #elif __powerpc__
 191 #define __NR_signalfd4 313
 192 #elif __s390x__
 193 #define __NR_signalfd4 322
 194 #elif __arm__
 195 #define __NR_signalfd4 355
 196 #elif __mips__ && _MIPS_SIM == _ABIO32
 197 #define __NR_signalfd4 4324
 198 #elif __mips__ && _MIPS_SIM == _ABI64
 199 #define __NR_signalfd4 5283
 200 #elif __mips__ && _MIPS_SIM == _ABIN32
 201 #define __NR_signalfd4 6287
 202 #endif
 203 #endif
 204
 205 #ifndef __NR_signalfd
 206 /* assume kernel headers are too old */
 207 #if __i386__
 208 #define __NR_signalfd 321
 209 #elif __x86_64__
 210 #define __NR_signalfd 282
 211 #elif __powerpc__
 212 #define __NR_signalfd 305
 213 #elif __s390x__
 214 #define __NR_signalfd 316
 215 #elif __arm__
 216 #define __NR_signalfd 349
 217 #elif __mips__ && _MIPS_SIM == _ABIO32
 218 #define __NR_signalfd 4317
 219 #elif __mips__ && _MIPS_SIM == _ABI64
 220 #define __NR_signalfd 5276
 221 #elif __mips__ && _MIPS_SIM == _ABIN32
 222 #define __NR_signalfd 6280
 223 #endif
 224 #endif
 225
 226 static inline int signalfd(int fd, const sigset_t *mask, int flags)
 227 {
 228         int retval;
 229
 230         retval = syscall(__NR_signalfd4, fd, mask, _NSIG / 8, flags);
 231         if (errno == ENOSYS && flags == 0)
 232                 retval = syscall(__NR_signalfd, fd, mask, _NSIG / 8);
 233
 234         return retval;
 235 }
 236 #endif
 237
 238 /* Define unshare() if missing from the C library */
 239 #ifndef HAVE_UNSHARE
 240 static inline int unshare(int flags)
 241 {
 242 #ifdef __NR_unshare
 243         return syscall(__NR_unshare, flags);
 244 #else
 245         errno = ENOSYS;
 246         return -1;
 247 #endif
 248 }
 249 #else
 250 extern int unshare(int);
 251 #endif
 252
 253 #endif /* __LXC_SYSCALL_WRAPPER_H */