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 library is free software; you can redistribute it and/or
   7  * modify it under the terms of the GNU Lesser General Public
   8  * License as published by the Free Software Foundation; either
   9  * version 2.1 of the License, or (at your option) any later version.
  10
  11  * This library is distributed in the hope that it will be useful,
  12  * but WITHOUT ANY WARRANTY; without even the implied warranty of
  13  * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14  * Lesser General Public License for more details.
  15
  16  * You should have received a copy of the GNU Lesser General Public License
  17  * along with this library; if not, write to the Free Software Foundation,
  18  * Inc., 51 Franklin Street, Fifth Floor, Boston, MA  02110-1301  USA
  19  */
  20
  21 #ifndef __LXC_SYSCALL_WRAPPER_H
  22 #define __LXC_SYSCALL_WRAPPER_H
  23
  24 #ifndef _GNU_SOURCE
  25 #define _GNU_SOURCE 1
  26 #endif
  27 #include <asm/unistd.h>
  28 #include <errno.h>
  29 #include <linux/keyctl.h>
  30 #include <sched.h>
  31 #include <stdint.h>
  32 #include <sys/syscall.h>
  33 #include <sys/types.h>
  34 #include <unistd.h>
  35
  36 #include "config.h"
  37
  38 #ifdef HAVE_LINUX_MEMFD_H
  39 #include <linux/memfd.h>
  40 #endif
  41
  42 #ifdef HAVE_SYS_SIGNALFD_H
  43 #include <sys/signalfd.h>
  44 #endif
  45
  46 typedef int32_t key_serial_t;
  47
  48 #if !HAVE_KEYCTL
  49 static inline long __keyctl(int cmd, unsigned long arg2, unsigned long arg3,
  50                             unsigned long arg4, unsigned long arg5)
  51 {
  52 #ifdef __NR_keyctl
  53         return syscall(__NR_keyctl, cmd, arg2, arg3, arg4, arg5);
  54 #else
  55         errno = ENOSYS;
  56         return -1;
  57 #endif
  58 }
  59 #define keyctl __keyctl
  60 #endif
  61
  62 #ifndef F_LINUX_SPECIFIC_BASE
  63 #define F_LINUX_SPECIFIC_BASE 1024
  64 #endif
  65 #ifndef F_ADD_SEALS
  66 #define F_ADD_SEALS (F_LINUX_SPECIFIC_BASE + 9)
  67 #define F_GET_SEALS (F_LINUX_SPECIFIC_BASE + 10)
  68 #endif
  69 #ifndef F_SEAL_SEAL
  70 #define F_SEAL_SEAL 0x0001
  71 #define F_SEAL_SHRINK 0x0002
  72 #define F_SEAL_GROW 0x0004
  73 #define F_SEAL_WRITE 0x0008
  74 #endif
  75
  76 #ifndef HAVE_MEMFD_CREATE
  77 static inline int memfd_create_lxc(const char *name, unsigned int flags) {
  78         #ifndef __NR_memfd_create
  79                 #if defined __i386__
  80                         #define __NR_memfd_create 356
  81                 #elif defined __x86_64__
  82                         #define __NR_memfd_create 319
  83                 #elif defined __arm__
  84                         #define __NR_memfd_create 385
  85                 #elif defined __aarch64__
  86                         #define __NR_memfd_create 279
  87                 #elif defined __s390__
  88                         #define __NR_memfd_create 350
  89                 #elif defined __powerpc__
  90                         #define __NR_memfd_create 360
  91                 #elif defined __sparc__
  92                         #define __NR_memfd_create 348
  93                 #elif defined __blackfin__
  94                         #define __NR_memfd_create 390
  95                 #elif defined __ia64__
  96                         #define __NR_memfd_create 1340
  97                 #elif defined _MIPS_SIM
  98                         #if _MIPS_SIM == _MIPS_SIM_ABI32
  99                                 #define __NR_memfd_create 4354
 100                         #endif
 101                         #if _MIPS_SIM == _MIPS_SIM_NABI32
 102                                 #define __NR_memfd_create 6318
 103                         #endif
 104                         #if _MIPS_SIM == _MIPS_SIM_ABI64
 105                                 #define __NR_memfd_create 5314
 106                         #endif
 107                 #endif
 108         #endif
 109         #ifdef __NR_memfd_create
 110         return syscall(__NR_memfd_create, name, flags);
 111         #else
 112         errno = ENOSYS;
 113         return -1;
 114         #endif
 115 }
 116 #define memfd_create memfd_create_lxc
 117 #else
 118 extern int memfd_create(const char *name, unsigned int flags);
 119 #endif
 120
 121 #if !HAVE_PIVOT_ROOT
 122 static int pivot_root(const char *new_root, const char *put_old)
 123 {
 124 #ifdef __NR_pivot_root
 125         return syscall(__NR_pivot_root, new_root, put_old);
 126 #else
 127         errno = ENOSYS;
 128         return -1;
 129 #endif
 130 }
 131 #else
 132 extern int pivot_root(const char *new_root, const char *put_old);
 133 #endif
 134
 135 #if !defined(__NR_setns) && !defined(__NR_set_ns)
 136         #if defined(__x86_64__)
 137                 #define __NR_setns 308
 138         #elif defined(__i386__)
 139                 #define __NR_setns 346
 140         #elif defined(__arm__)
 141                 #define __NR_setns 375
 142         #elif defined(__aarch64__)
 143                 #define __NR_setns 375
 144         #elif defined(__powerpc__)
 145                 #define __NR_setns 350
 146         #elif defined(__s390__)
 147                 #define __NR_setns 339
 148         #endif
 149 #endif
 150
 151 /* Define sethostname() if missing from the C library */
 152 #ifndef HAVE_SETHOSTNAME
 153 static inline int sethostname(const char *name, size_t len)
 154 {
 155 #ifdef __NR_sethostname
 156         return syscall(__NR_sethostname, name, len);
 157 #else
 158         errno = ENOSYS;
 159         return -1;
 160 #endif
 161 }
 162 #endif
 163
 164 /* Define setns() if missing from the C library */
 165 #ifndef HAVE_SETNS
 166 static inline int setns(int fd, int nstype)
 167 {
 168 #ifdef __NR_setns
 169         return syscall(__NR_setns, fd, nstype);
 170 #elif defined(__NR_set_ns)
 171         return syscall(__NR_set_ns, fd, nstype);
 172 #else
 173         errno = ENOSYS;
 174         return -1;
 175 #endif
 176 }
 177 #endif
 178
 179 #ifndef HAVE_SYS_SIGNALFD_H
 180 struct signalfd_siginfo {
 181         uint32_t ssi_signo;
 182         int32_t ssi_errno;
 183         int32_t ssi_code;
 184         uint32_t ssi_pid;
 185         uint32_t ssi_uid;
 186         int32_t ssi_fd;
 187         uint32_t ssi_tid;
 188         uint32_t ssi_band;
 189         uint32_t ssi_overrun;
 190         uint32_t ssi_trapno;
 191         int32_t ssi_status;
 192         int32_t ssi_int;
 193         uint64_t ssi_ptr;
 194         uint64_t ssi_utime;
 195         uint64_t ssi_stime;
 196         uint64_t ssi_addr;
 197         uint8_t __pad[48];
 198 };
 199
 200 #ifndef __NR_signalfd4
 201 /* assume kernel headers are too old */
 202 #if __i386__
 203 #define __NR_signalfd4 327
 204 #elif __x86_64__
 205 #define __NR_signalfd4 289
 206 #elif __powerpc__
 207 #define __NR_signalfd4 313
 208 #elif __s390x__
 209 #define __NR_signalfd4 322
 210 #elif __arm__
 211 #define __NR_signalfd4 355
 212 #elif __mips__ && _MIPS_SIM == _ABIO32
 213 #define __NR_signalfd4 4324
 214 #elif __mips__ && _MIPS_SIM == _ABI64
 215 #define __NR_signalfd4 5283
 216 #elif __mips__ && _MIPS_SIM == _ABIN32
 217 #define __NR_signalfd4 6287
 218 #endif
 219 #endif
 220
 221 #ifndef __NR_signalfd
 222 /* assume kernel headers are too old */
 223 #if __i386__
 224 #define __NR_signalfd 321
 225 #elif __x86_64__
 226 #define __NR_signalfd 282
 227 #elif __powerpc__
 228 #define __NR_signalfd 305
 229 #elif __s390x__
 230 #define __NR_signalfd 316
 231 #elif __arm__
 232 #define __NR_signalfd 349
 233 #elif __mips__ && _MIPS_SIM == _ABIO32
 234 #define __NR_signalfd 4317
 235 #elif __mips__ && _MIPS_SIM == _ABI64
 236 #define __NR_signalfd 5276
 237 #elif __mips__ && _MIPS_SIM == _ABIN32
 238 #define __NR_signalfd 6280
 239 #endif
 240 #endif
 241
 242 static inline int signalfd(int fd, const sigset_t *mask, int flags)
 243 {
 244         int retval;
 245
 246         retval = syscall(__NR_signalfd4, fd, mask, _NSIG / 8, flags);
 247         if (errno == ENOSYS && flags == 0)
 248                 retval = syscall(__NR_signalfd, fd, mask, _NSIG / 8);
 249
 250         return retval;
 251 }
 252 #endif
 253
 254 /* Define unshare() if missing from the C library */
 255 #ifndef HAVE_UNSHARE
 256 static inline int unshare(int flags)
 257 {
 258 #ifdef __NR_unshare
 259         return syscall(__NR_unshare, flags);
 260 #else
 261         errno = ENOSYS;
 262         return -1;
 263 #endif
 264 }
 265 #else
 266 extern int unshare(int);
 267 #endif
 268
 269 #endif /* __LXC_SYSCALL_WRAPPER_H */