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(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 #else
 117 extern int memfd_create(const char *name, unsigned int flags);
 118 #endif
 119
 120 #if !HAVE_PIVOT_ROOT
 121 static int pivot_root(const char *new_root, const char *put_old)
 122 {
 123 #ifdef __NR_pivot_root
 124         return syscall(__NR_pivot_root, new_root, put_old);
 125 #else
 126         errno = ENOSYS;
 127         return -1;
 128 #endif
 129 }
 130 #else
 131 extern int pivot_root(const char *new_root, const char *put_old);
 132 #endif
 133
 134 #if !defined(__NR_setns) && !defined(__NR_set_ns)
 135         #if defined(__x86_64__)
 136                 #define __NR_setns 308
 137         #elif defined(__i386__)
 138                 #define __NR_setns 346
 139         #elif defined(__arm__)
 140                 #define __NR_setns 375
 141         #elif defined(__aarch64__)
 142                 #define __NR_setns 375
 143         #elif defined(__powerpc__)
 144                 #define __NR_setns 350
 145         #elif defined(__s390__)
 146                 #define __NR_setns 339
 147         #endif
 148 #endif
 149
 150 /* Define sethostname() if missing from the C library */
 151 #ifndef HAVE_SETHOSTNAME
 152 static inline int sethostname(const char *name, size_t len)
 153 {
 154 #ifdef __NR_sethostname
 155         return syscall(__NR_sethostname, name, len);
 156 #else
 157         errno = ENOSYS;
 158         return -1;
 159 #endif
 160 }
 161 #endif
 162
 163 /* Define setns() if missing from the C library */
 164 #ifndef HAVE_SETNS
 165 static inline int setns(int fd, int nstype)
 166 {
 167 #ifdef __NR_setns
 168         return syscall(__NR_setns, fd, nstype);
 169 #elif defined(__NR_set_ns)
 170         return syscall(__NR_set_ns, fd, nstype);
 171 #else
 172         errno = ENOSYS;
 173         return -1;
 174 #endif
 175 }
 176 #endif
 177
 178 #ifndef HAVE_SYS_SIGNALFD_H
 179 struct signalfd_siginfo {
 180         uint32_t ssi_signo;
 181         int32_t ssi_errno;
 182         int32_t ssi_code;
 183         uint32_t ssi_pid;
 184         uint32_t ssi_uid;
 185         int32_t ssi_fd;
 186         uint32_t ssi_tid;
 187         uint32_t ssi_band;
 188         uint32_t ssi_overrun;
 189         uint32_t ssi_trapno;
 190         int32_t ssi_status;
 191         int32_t ssi_int;
 192         uint64_t ssi_ptr;
 193         uint64_t ssi_utime;
 194         uint64_t ssi_stime;
 195         uint64_t ssi_addr;
 196         uint8_t __pad[48];
 197 };
 198
 199 #ifndef __NR_signalfd4
 200 /* assume kernel headers are too old */
 201 #if __i386__
 202 #define __NR_signalfd4 327
 203 #elif __x86_64__
 204 #define __NR_signalfd4 289
 205 #elif __powerpc__
 206 #define __NR_signalfd4 313
 207 #elif __s390x__
 208 #define __NR_signalfd4 322
 209 #elif __arm__
 210 #define __NR_signalfd4 355
 211 #elif __mips__ && _MIPS_SIM == _ABIO32
 212 #define __NR_signalfd4 4324
 213 #elif __mips__ && _MIPS_SIM == _ABI64
 214 #define __NR_signalfd4 5283
 215 #elif __mips__ && _MIPS_SIM == _ABIN32
 216 #define __NR_signalfd4 6287
 217 #endif
 218 #endif
 219
 220 #ifndef __NR_signalfd
 221 /* assume kernel headers are too old */
 222 #if __i386__
 223 #define __NR_signalfd 321
 224 #elif __x86_64__
 225 #define __NR_signalfd 282
 226 #elif __powerpc__
 227 #define __NR_signalfd 305
 228 #elif __s390x__
 229 #define __NR_signalfd 316
 230 #elif __arm__
 231 #define __NR_signalfd 349
 232 #elif __mips__ && _MIPS_SIM == _ABIO32
 233 #define __NR_signalfd 4317
 234 #elif __mips__ && _MIPS_SIM == _ABI64
 235 #define __NR_signalfd 5276
 236 #elif __mips__ && _MIPS_SIM == _ABIN32
 237 #define __NR_signalfd 6280
 238 #endif
 239 #endif
 240
 241 static inline int signalfd(int fd, const sigset_t *mask, int flags)
 242 {
 243         int retval;
 244
 245         retval = syscall(__NR_signalfd4, fd, mask, _NSIG / 8, flags);
 246         if (errno == ENOSYS && flags == 0)
 247                 retval = syscall(__NR_signalfd, fd, mask, _NSIG / 8);
 248
 249         return retval;
 250 }
 251 #endif
 252
 253 /* Define unshare() if missing from the C library */
 254 #ifndef HAVE_UNSHARE
 255 static inline int unshare(int flags)
 256 {
 257 #ifdef __NR_unshare
 258         return syscall(__NR_unshare, flags);
 259 #else
 260         errno = ENOSYS;
 261         return -1;
 262 #endif
 263 }
 264 #else
 265 extern int unshare(int);
 266 #endif
 267
 268 #endif /* __LXC_SYSCALL_WRAPPER_H */