1 /* 2 * BSD syscalls 3 * 4 * Copyright (c) 2003-2008 Fabrice Bellard 5 * Copyright (c) 2013-2014 Stacey D. Son 6 * 7 * This program is free software; you can redistribute it and/or modify 8 * it under the terms of the GNU General Public License as published by 9 * the Free Software Foundation; either version 2 of the License, or 10 * (at your option) any later version. 11 * 12 * This program is distributed in the hope that it will be useful, 13 * but WITHOUT ANY WARRANTY; without even the implied warranty of 14 * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the 15 * GNU General Public License for more details. 16 * 17 * You should have received a copy of the GNU General Public License 18 * along with this program; if not, see <http://www.gnu.org/licenses/>. 19 */ 20 21 /* 22 * We need the FreeBSD "legacy" definitions. Rust needs the FreeBSD 11 system 23 * calls since it doesn't use libc at all, so we have to emulate that despite 24 * FreeBSD 11 being EOL'd. 25 */ 26 #define _WANT_FREEBSD11_STAT 27 #define _WANT_FREEBSD11_STATFS 28 #define _WANT_FREEBSD11_DIRENT 29 #define _WANT_KERNEL_ERRNO 30 #define _WANT_SEMUN 31 #include "qemu/osdep.h" 32 #include "qemu/cutils.h" 33 #include "qemu/path.h" 34 #include <sys/syscall.h> 35 #include <sys/param.h> 36 #include <sys/sysctl.h> 37 #include <utime.h> 38 39 #include "qemu.h" 40 #include "signal-common.h" 41 #include "user/syscall-trace.h" 42 43 #include "bsd-file.h" 44 #include "bsd-proc.h" 45 46 /* I/O */ 47 safe_syscall3(int, open, const char *, path, int, flags, mode_t, mode); 48 safe_syscall4(int, openat, int, fd, const char *, path, int, flags, mode_t, 49 mode); 50 51 safe_syscall3(ssize_t, read, int, fd, void *, buf, size_t, nbytes); 52 safe_syscall4(ssize_t, pread, int, fd, void *, buf, size_t, nbytes, off_t, 53 offset); 54 safe_syscall3(ssize_t, readv, int, fd, const struct iovec *, iov, int, iovcnt); 55 safe_syscall4(ssize_t, preadv, int, fd, const struct iovec *, iov, int, iovcnt, 56 off_t, offset); 57 58 safe_syscall3(ssize_t, write, int, fd, void *, buf, size_t, nbytes); 59 safe_syscall4(ssize_t, pwrite, int, fd, void *, buf, size_t, nbytes, off_t, 60 offset); 61 safe_syscall3(ssize_t, writev, int, fd, const struct iovec *, iov, int, iovcnt); 62 safe_syscall4(ssize_t, pwritev, int, fd, const struct iovec *, iov, int, iovcnt, 63 off_t, offset); 64 65 void target_set_brk(abi_ulong new_brk) 66 { 67 } 68 69 /* 70 * errno conversion. 71 */ 72 abi_long get_errno(abi_long ret) 73 { 74 if (ret == -1) { 75 return -host_to_target_errno(errno); 76 } else { 77 return ret; 78 } 79 } 80 81 int host_to_target_errno(int err) 82 { 83 /* 84 * All the BSDs have the property that the error numbers are uniform across 85 * all architectures for a given BSD, though they may vary between different 86 * BSDs. 87 */ 88 return err; 89 } 90 91 bool is_error(abi_long ret) 92 { 93 return (abi_ulong)ret >= (abi_ulong)(-4096); 94 } 95 96 /* 97 * Unlocks a iovec. Unlike unlock_iovec, it assumes the tvec array itself is 98 * already locked from target_addr. It will be unlocked as well as all the iovec 99 * elements. 100 */ 101 static void helper_unlock_iovec(struct target_iovec *target_vec, 102 abi_ulong target_addr, struct iovec *vec, 103 int count, int copy) 104 { 105 for (int i = 0; i < count; i++) { 106 abi_ulong base = tswapal(target_vec[i].iov_base); 107 108 if (vec[i].iov_base) { 109 unlock_user(vec[i].iov_base, base, copy ? vec[i].iov_len : 0); 110 } 111 } 112 unlock_user(target_vec, target_addr, 0); 113 } 114 115 struct iovec *lock_iovec(int type, abi_ulong target_addr, 116 int count, int copy) 117 { 118 struct target_iovec *target_vec; 119 struct iovec *vec; 120 abi_ulong total_len, max_len; 121 int i; 122 int err = 0; 123 124 if (count == 0) { 125 errno = 0; 126 return NULL; 127 } 128 if (count < 0 || count > IOV_MAX) { 129 errno = EINVAL; 130 return NULL; 131 } 132 133 vec = g_try_new0(struct iovec, count); 134 if (vec == NULL) { 135 errno = ENOMEM; 136 return NULL; 137 } 138 139 target_vec = lock_user(VERIFY_READ, target_addr, 140 count * sizeof(struct target_iovec), 1); 141 if (target_vec == NULL) { 142 err = EFAULT; 143 goto fail2; 144 } 145 146 max_len = 0x7fffffff & MIN(TARGET_PAGE_MASK, PAGE_MASK); 147 total_len = 0; 148 149 for (i = 0; i < count; i++) { 150 abi_ulong base = tswapal(target_vec[i].iov_base); 151 abi_long len = tswapal(target_vec[i].iov_len); 152 153 if (len < 0) { 154 err = EINVAL; 155 goto fail; 156 } else if (len == 0) { 157 /* Zero length pointer is ignored. */ 158 vec[i].iov_base = 0; 159 } else { 160 vec[i].iov_base = lock_user(type, base, len, copy); 161 /* 162 * If the first buffer pointer is bad, this is a fault. But 163 * subsequent bad buffers will result in a partial write; this is 164 * realized by filling the vector with null pointers and zero 165 * lengths. 166 */ 167 if (!vec[i].iov_base) { 168 if (i == 0) { 169 err = EFAULT; 170 goto fail; 171 } else { 172 /* 173 * Fail all the subsequent addresses, they are already 174 * zero'd. 175 */ 176 goto out; 177 } 178 } 179 if (len > max_len - total_len) { 180 len = max_len - total_len; 181 } 182 } 183 vec[i].iov_len = len; 184 total_len += len; 185 } 186 out: 187 unlock_user(target_vec, target_addr, 0); 188 return vec; 189 190 fail: 191 helper_unlock_iovec(target_vec, target_addr, vec, i, copy); 192 fail2: 193 g_free(vec); 194 errno = err; 195 return NULL; 196 } 197 198 void unlock_iovec(struct iovec *vec, abi_ulong target_addr, 199 int count, int copy) 200 { 201 struct target_iovec *target_vec; 202 203 target_vec = lock_user(VERIFY_READ, target_addr, 204 count * sizeof(struct target_iovec), 1); 205 if (target_vec) { 206 helper_unlock_iovec(target_vec, target_addr, vec, count, copy); 207 } 208 209 g_free(vec); 210 } 211 212 /* 213 * All errnos that freebsd_syscall() returns must be -TARGET_<errcode>. 214 */ 215 static abi_long freebsd_syscall(void *cpu_env, int num, abi_long arg1, 216 abi_long arg2, abi_long arg3, abi_long arg4, 217 abi_long arg5, abi_long arg6, abi_long arg7, 218 abi_long arg8) 219 { 220 abi_long ret; 221 222 switch (num) { 223 /* 224 * process system calls 225 */ 226 case TARGET_FREEBSD_NR_exit: /* exit(2) */ 227 ret = do_bsd_exit(cpu_env, arg1); 228 break; 229 230 /* 231 * File system calls. 232 */ 233 case TARGET_FREEBSD_NR_read: /* read(2) */ 234 ret = do_bsd_read(arg1, arg2, arg3); 235 break; 236 237 case TARGET_FREEBSD_NR_pread: /* pread(2) */ 238 ret = do_bsd_pread(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6); 239 break; 240 241 case TARGET_FREEBSD_NR_readv: /* readv(2) */ 242 ret = do_bsd_readv(arg1, arg2, arg3); 243 break; 244 245 case TARGET_FREEBSD_NR_preadv: /* preadv(2) */ 246 ret = do_bsd_preadv(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6); 247 248 case TARGET_FREEBSD_NR_write: /* write(2) */ 249 ret = do_bsd_write(arg1, arg2, arg3); 250 break; 251 252 case TARGET_FREEBSD_NR_pwrite: /* pwrite(2) */ 253 ret = do_bsd_pwrite(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6); 254 break; 255 256 case TARGET_FREEBSD_NR_writev: /* writev(2) */ 257 ret = do_bsd_writev(arg1, arg2, arg3); 258 break; 259 260 case TARGET_FREEBSD_NR_pwritev: /* pwritev(2) */ 261 ret = do_bsd_pwritev(cpu_env, arg1, arg2, arg3, arg4, arg5, arg6); 262 break; 263 264 case TARGET_FREEBSD_NR_open: /* open(2) */ 265 ret = do_bsd_open(arg1, arg2, arg3); 266 break; 267 268 case TARGET_FREEBSD_NR_openat: /* openat(2) */ 269 ret = do_bsd_openat(arg1, arg2, arg3, arg4); 270 break; 271 272 case TARGET_FREEBSD_NR_close: /* close(2) */ 273 ret = do_bsd_close(arg1); 274 break; 275 276 case TARGET_FREEBSD_NR_fdatasync: /* fdatasync(2) */ 277 ret = do_bsd_fdatasync(arg1); 278 break; 279 280 case TARGET_FREEBSD_NR_fsync: /* fsync(2) */ 281 ret = do_bsd_fsync(arg1); 282 break; 283 284 case TARGET_FREEBSD_NR_freebsd12_closefrom: /* closefrom(2) */ 285 ret = do_bsd_closefrom(arg1); 286 break; 287 288 case TARGET_FREEBSD_NR_revoke: /* revoke(2) */ 289 ret = do_bsd_revoke(arg1); 290 break; 291 292 case TARGET_FREEBSD_NR_access: /* access(2) */ 293 ret = do_bsd_access(arg1, arg2); 294 break; 295 296 case TARGET_FREEBSD_NR_eaccess: /* eaccess(2) */ 297 ret = do_bsd_eaccess(arg1, arg2); 298 break; 299 300 case TARGET_FREEBSD_NR_faccessat: /* faccessat(2) */ 301 ret = do_bsd_faccessat(arg1, arg2, arg3, arg4); 302 break; 303 304 case TARGET_FREEBSD_NR_chdir: /* chdir(2) */ 305 ret = do_bsd_chdir(arg1); 306 break; 307 308 case TARGET_FREEBSD_NR_fchdir: /* fchdir(2) */ 309 ret = do_bsd_fchdir(arg1); 310 break; 311 312 case TARGET_FREEBSD_NR_rename: /* rename(2) */ 313 ret = do_bsd_rename(arg1, arg2); 314 break; 315 316 case TARGET_FREEBSD_NR_renameat: /* renameat(2) */ 317 ret = do_bsd_renameat(arg1, arg2, arg3, arg4); 318 break; 319 320 case TARGET_FREEBSD_NR_link: /* link(2) */ 321 ret = do_bsd_link(arg1, arg2); 322 break; 323 324 case TARGET_FREEBSD_NR_linkat: /* linkat(2) */ 325 ret = do_bsd_linkat(arg1, arg2, arg3, arg4, arg5); 326 break; 327 328 case TARGET_FREEBSD_NR_unlink: /* unlink(2) */ 329 ret = do_bsd_unlink(arg1); 330 break; 331 332 case TARGET_FREEBSD_NR_unlinkat: /* unlinkat(2) */ 333 ret = do_bsd_unlinkat(arg1, arg2, arg3); 334 break; 335 336 case TARGET_FREEBSD_NR_mkdir: /* mkdir(2) */ 337 ret = do_bsd_mkdir(arg1, arg2); 338 break; 339 340 case TARGET_FREEBSD_NR_mkdirat: /* mkdirat(2) */ 341 ret = do_bsd_mkdirat(arg1, arg2, arg3); 342 break; 343 344 default: 345 qemu_log_mask(LOG_UNIMP, "Unsupported syscall: %d\n", num); 346 ret = -TARGET_ENOSYS; 347 break; 348 } 349 350 return ret; 351 } 352 353 /* 354 * do_freebsd_syscall() should always have a single exit point at the end so 355 * that actions, such as logging of syscall results, can be performed. This 356 * as a wrapper around freebsd_syscall() so that actually happens. Since 357 * that is a singleton, modern compilers will inline it anyway... 358 */ 359 abi_long do_freebsd_syscall(void *cpu_env, int num, abi_long arg1, 360 abi_long arg2, abi_long arg3, abi_long arg4, 361 abi_long arg5, abi_long arg6, abi_long arg7, 362 abi_long arg8) 363 { 364 CPUState *cpu = env_cpu(cpu_env); 365 int ret; 366 367 trace_guest_user_syscall(cpu, num, arg1, arg2, arg3, arg4, arg5, arg6, arg7, arg8); 368 if (do_strace) { 369 print_freebsd_syscall(num, arg1, arg2, arg3, arg4, arg5, arg6); 370 } 371 372 ret = freebsd_syscall(cpu_env, num, arg1, arg2, arg3, arg4, arg5, arg6, 373 arg7, arg8); 374 if (do_strace) { 375 print_freebsd_syscall_ret(num, ret); 376 } 377 trace_guest_user_syscall_ret(cpu, num, ret); 378 379 return ret; 380 } 381 382 void syscall_init(void) 383 { 384 } 385