osdep.c

   1 /*
   2  * QEMU low level functions
   3  *
   4  * Copyright (c) 2003 Fabrice Bellard
   5  *
   6  * Permission is hereby granted, free of charge, to any person obtaining a copy
   7  * of this software and associated documentation files (the "Software"), to deal
   8  * in the Software without restriction, including without limitation the rights
   9  * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
  10  * copies of the Software, and to permit persons to whom the Software is
  11  * furnished to do so, subject to the following conditions:
  12  *
  13  * The above copyright notice and this permission notice shall be included in
  14  * all copies or substantial portions of the Software.
  15  *
  16  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
  17  * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
  18  * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL
  19  * THE AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
  20  * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
  21  * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
  22  * THE SOFTWARE.
  23  */
  24 #include <stdlib.h>
  25 #include <stdio.h>
  26 #include <stdarg.h>
  27 #include <stdbool.h>
  28 #include <string.h>
  29 #include <errno.h>
  30 #include <unistd.h>
  31 #include <fcntl.h>
  32
  33 /* Needed early for CONFIG_BSD etc. */
  34 #include "config-host.h"
  35
  36 #if defined(CONFIG_MADVISE) || defined(CONFIG_POSIX_MADVISE)
  37 #include <sys/mman.h>
  38 #endif
  39
  40 #ifdef CONFIG_SOLARIS
  41 #include <sys/types.h>
  42 #include <sys/statvfs.h>
  43 /* See MySQL bug #7156 (http://bugs.mysql.com/bug.php?id=7156) for
  44    discussion about Solaris header problems */
  45 extern int madvise(caddr_t, size_t, int);
  46 #endif
  47
  48 #include "qemu-common.h"
  49 #include "trace.h"
  50 #include "qemu_socket.h"
  51
  52 static bool fips_enabled = false;
  53
  54 static const char *qemu_version = QEMU_VERSION;
  55
  56 int socket_set_cork(int fd, int v)
  57 {
  58 #if defined(SOL_TCP) && defined(TCP_CORK)
  59     return setsockopt(fd, SOL_TCP, TCP_CORK, &v, sizeof(v));
  60 #else
  61     return 0;
  62 #endif
  63 }
  64
  65 int qemu_madvise(void *addr, size_t len, int advice)
  66 {
  67     if (advice == QEMU_MADV_INVALID) {
  68         errno = EINVAL;
  69         return -1;
  70     }
  71 #if defined(CONFIG_MADVISE)
  72     return madvise(addr, len, advice);
  73 #elif defined(CONFIG_POSIX_MADVISE)
  74     return posix_madvise(addr, len, advice);
  75 #else
  76     errno = EINVAL;
  77     return -1;
  78 #endif
  79 }
  80
  81
  82 /*
  83  * Opens a file with FD_CLOEXEC set
  84  */
  85 int qemu_open(const char *name, int flags, ...)
  86 {
  87     int ret;
  88     int mode = 0;
  89
  90     if (flags & O_CREAT) {
  91         va_list ap;
  92
  93         va_start(ap, flags);
  94         mode = va_arg(ap, int);
  95         va_end(ap);
  96     }
  97
  98 #ifdef O_CLOEXEC
  99     ret = open(name, flags | O_CLOEXEC, mode);
 100 #else
 101     ret = open(name, flags, mode);
 102     if (ret >= 0) {
 103         qemu_set_cloexec(ret);
 104     }
 105 #endif
 106
 107     return ret;
 108 }
 109
 110 /*
 111  * A variant of write(2) which handles partial write.
 112  *
 113  * Return the number of bytes transferred.
 114  * Set errno if fewer than `count' bytes are written.
 115  *
 116  * This function don't work with non-blocking fd's.
 117  * Any of the possibilities with non-bloking fd's is bad:
 118  *   - return a short write (then name is wrong)
 119  *   - busy wait adding (errno == EAGAIN) to the loop
 120  */
 121 ssize_t qemu_write_full(int fd, const void *buf, size_t count)
 122 {
 123     ssize_t ret = 0;
 124     ssize_t total = 0;
 125
 126     while (count) {
 127         ret = write(fd, buf, count);
 128         if (ret < 0) {
 129             if (errno == EINTR)
 130                 continue;
 131             break;
 132         }
 133
 134         count -= ret;
 135         buf += ret;
 136         total += ret;
 137     }
 138
 139     return total;
 140 }
 141
 142 /*
 143  * Opens a socket with FD_CLOEXEC set
 144  */
 145 int qemu_socket(int domain, int type, int protocol)
 146 {
 147     int ret;
 148
 149 #ifdef SOCK_CLOEXEC
 150     ret = socket(domain, type | SOCK_CLOEXEC, protocol);
 151     if (ret != -1 || errno != EINVAL) {
 152         return ret;
 153     }
 154 #endif
 155     ret = socket(domain, type, protocol);
 156     if (ret >= 0) {
 157         qemu_set_cloexec(ret);
 158     }
 159
 160     return ret;
 161 }
 162
 163 /*
 164  * Accept a connection and set FD_CLOEXEC
 165  */
 166 int qemu_accept(int s, struct sockaddr *addr, socklen_t *addrlen)
 167 {
 168     int ret;
 169
 170 #ifdef CONFIG_ACCEPT4
 171     ret = accept4(s, addr, addrlen, SOCK_CLOEXEC);
 172     if (ret != -1 || errno != ENOSYS) {
 173         return ret;
 174     }
 175 #endif
 176     ret = accept(s, addr, addrlen);
 177     if (ret >= 0) {
 178         qemu_set_cloexec(ret);
 179     }
 180
 181     return ret;
 182 }
 183
 184 /*
 185  * A variant of send(2) which handles partial write.
 186  *
 187  * Return the number of bytes transferred, which is only
 188  * smaller than `count' if there is an error.
 189  *
 190  * This function won't work with non-blocking fd's.
 191  * Any of the possibilities with non-bloking fd's is bad:
 192  *   - return a short write (then name is wrong)
 193  *   - busy wait adding (errno == EAGAIN) to the loop
 194  */
 195 ssize_t qemu_send_full(int fd, const void *buf, size_t count, int flags)
 196 {
 197     ssize_t ret = 0;
 198     ssize_t total = 0;
 199
 200     while (count) {
 201         ret = send(fd, buf, count, flags);
 202         if (ret < 0) {
 203             if (errno == EINTR) {
 204                 continue;
 205             }
 206             break;
 207         }
 208
 209         count -= ret;
 210         buf += ret;
 211         total += ret;
 212     }
 213
 214     return total;
 215 }
 216
 217 /*
 218  * A variant of recv(2) which handles partial write.
 219  *
 220  * Return the number of bytes transferred, which is only
 221  * smaller than `count' if there is an error.
 222  *
 223  * This function won't work with non-blocking fd's.
 224  * Any of the possibilities with non-bloking fd's is bad:
 225  *   - return a short write (then name is wrong)
 226  *   - busy wait adding (errno == EAGAIN) to the loop
 227  */
 228 ssize_t qemu_recv_full(int fd, void *buf, size_t count, int flags)
 229 {
 230     ssize_t ret = 0;
 231     ssize_t total = 0;
 232
 233     while (count) {
 234         ret = qemu_recv(fd, buf, count, flags);
 235         if (ret <= 0) {
 236             if (ret < 0 && errno == EINTR) {
 237                 continue;
 238             }
 239             break;
 240         }
 241
 242         count -= ret;
 243         buf += ret;
 244         total += ret;
 245     }
 246
 247     return total;
 248 }
 249
 250 void qemu_set_version(const char *version)
 251 {
 252     qemu_version = version;
 253 }
 254
 255 const char *qemu_get_version(void)
 256 {
 257     return qemu_version;
 258 }
 259
 260 void fips_set_state(bool requested)
 261 {
 262 #ifdef __linux__
 263     if (requested) {
 264         FILE *fds = fopen("/proc/sys/crypto/fips_enabled", "r");
 265         if (fds != NULL) {
 266             fips_enabled = (fgetc(fds) == '1');
 267             fclose(fds);
 268         }
 269     }
 270 #else
 271     fips_enabled = false;
 272 #endif /* __linux__ */
 273
 274 #ifdef _FIPS_DEBUG
 275     fprintf(stderr, "FIPS mode %s (requested %s)\n",
 276             (fips_enabled ? "enabled" : "disabled"),
 277             (requested ? "enabled" : "disabled"));
 278 #endif
 279 }
 280
 281 bool fips_get_state(void)
 282 {
 283     return fips_enabled;
 284 }