mono/io-layer/daemon-messages.c

   1 /*
   2  * daemon-messages.c:  Communications to and from the handle daemon
   3  *
   4  * Author:
   5  *      Dick Porter (dick@ximian.com)
   6  *
   7  * (C) 2002 Ximian, Inc.
   8  */
   9
  10 #include <config.h>
  11 #include <glib.h>
  12 #include <pthread.h>
  13 #include <errno.h>
  14 #include <string.h>
  15 #include <sys/types.h>
  16 #include <sys/socket.h>
  17 /* Freebsd needs this included explicitly, but it doesn't hurt on Linux */
  18 #ifdef HAVE_SYS_UIO_H
  19 #    include <sys/uio.h>
  20 #endif
  21
  22 #ifndef HAVE_MSG_NOSIGNAL
  23 #include <signal.h>
  24 #endif
  25
  26 #include <mono/io-layer/wapi.h>
  27 #include <mono/io-layer/daemon-messages.h>
  28
  29 /* Solaris doesn't define these */
  30 #ifndef CMSG_LEN
  31 #define CMSG_LEN(size)    (sizeof (struct cmsghdr) + (size))
  32 #endif
  33 #ifndef CMSG_SPACE
  34 #define CMSG_SPACE(size)  (sizeof (struct cmsghdr) + (size))
  35 #endif
  36
  37 #define LOGDEBUG(...)
  38 // #define LOGDEBUG(...) g_message(__VA_ARGS__)
  39
  40 static mono_mutex_t req_mutex;
  41 static mono_once_t attr_key_once = MONO_ONCE_INIT;
  42 static mono_mutexattr_t attr;
  43
  44 static void attr_init (void)
  45 {
  46         int ret;
  47
  48         ret = mono_mutexattr_init (&attr);
  49         g_assert (ret == 0);
  50
  51         ret = mono_mutexattr_settype (&attr, MONO_MUTEX_RECURSIVE);
  52         g_assert (ret == 0);
  53
  54         ret = mono_mutex_init (&req_mutex, &attr);
  55         g_assert (ret == 0);
  56 }
  57
  58 /* Send request on fd, wait for response (called by applications, not
  59  * the daemon, indirectly through _wapi_daemon_request_response and
  60  * _wapi_daemon_request_response_with_fds)
  61  */
  62 static void _wapi_daemon_request_response_internal (int fd,
  63                                                     struct msghdr *msg,
  64                                                     WapiHandleResponse *resp)
  65 {
  66         int ret;
  67 #ifndef HAVE_MSG_NOSIGNAL
  68         void (*old_sigpipe)(int);
  69 #endif
  70
  71         mono_once (&attr_key_once, attr_init);
  72
  73         /* Serialise requests to the daemon from the same process.  We
  74          * rely on request turnaround time being minimal anyway, so
  75          * performance shouldnt suffer from the mutex.
  76          */
  77         pthread_cleanup_push ((void(*)(void *))mono_mutex_unlock_in_cleanup,
  78                               (void *)&req_mutex);
  79         ret = mono_mutex_lock (&req_mutex);
  80         g_assert (ret == 0);
  81
  82 #ifdef HAVE_MSG_NOSIGNAL
  83         do {
  84                 ret=sendmsg (fd, msg, MSG_NOSIGNAL);
  85         }
  86         while (ret==-1 && errno==EINTR);
  87 #else
  88         old_sigpipe = signal (SIGPIPE, SIG_IGN);
  89         do {
  90                 ret=sendmsg (fd, msg, 0);
  91         }
  92         while (ret==-1 && errno==EINTR);
  93 #endif
  94
  95         if(ret!=sizeof(WapiHandleRequest)) {
  96                 if(errno==EPIPE) {
  97                         g_critical ("%s: The handle daemon vanished!", __func__);
  98                         exit (-1);
  99                 } else {
 100                         g_warning ("%s: Send error: %s", __func__,
 101                                    strerror (errno));
 102                         g_assert_not_reached ();
 103                 }
 104         }
 105
 106 #ifdef HAVE_MSG_NOSIGNAL
 107         do {
 108                 ret=recv (fd, resp, sizeof(WapiHandleResponse), MSG_NOSIGNAL);
 109         }
 110         while (ret==-1 && errno==EINTR);
 111 #else
 112         do {
 113                 ret=recv (fd, resp, sizeof(WapiHandleResponse), 0);
 114         }
 115         while (ret==-1 && errno==EINTR);
 116         signal (SIGPIPE, old_sigpipe);
 117 #endif
 118
 119         if(ret==-1) {
 120                 if(errno==EPIPE) {
 121                         g_critical ("%s: The handle daemon vanished!", __func__);
 122                         exit (-1);
 123                 } else {
 124                         g_warning ("%s: Send error: %s", __func__, strerror (errno));
 125                         g_assert_not_reached ();
 126                 }
 127         }
 128
 129         ret = mono_mutex_unlock (&req_mutex);
 130         g_assert (ret == 0);
 131
 132         pthread_cleanup_pop (0);
 133 }
 134
 135 /* Send request on fd with filedescriptors, wait for response (called
 136  * by applications, not the daemon)
 137  */
 138 void _wapi_daemon_request_response_with_fds (int fd, WapiHandleRequest *req,
 139                                              WapiHandleResponse *resp,
 140                                              int in_fd, int out_fd, int err_fd)
 141 {
 142         struct msghdr msg={0};
 143         struct cmsghdr *cmsg;
 144         struct iovec iov;
 145         char cmsgdata[CMSG_SPACE (sizeof(int)*3)];
 146         int *fdptr;
 147
 148         msg.msg_name=NULL;
 149         msg.msg_namelen=0;
 150         msg.msg_iov=&iov;
 151         msg.msg_iovlen=1;
 152         msg.msg_control=cmsgdata;
 153         msg.msg_controllen=sizeof(cmsgdata);
 154         msg.msg_flags=0;
 155
 156         iov.iov_base=req;
 157         iov.iov_len=sizeof(WapiHandleRequest);
 158
 159         cmsg=CMSG_FIRSTHDR (&msg);
 160         cmsg->cmsg_len=CMSG_LEN (sizeof(int)*3);
 161         cmsg->cmsg_level=SOL_SOCKET;
 162         cmsg->cmsg_type=SCM_RIGHTS;
 163         fdptr=(int *)CMSG_DATA (cmsg);
 164         fdptr[0]=in_fd;
 165         fdptr[1]=out_fd;
 166         fdptr[2]=err_fd;
 167
 168         msg.msg_controllen=CMSG_SPACE (sizeof(int)*3);
 169
 170         _wapi_daemon_request_response_internal (fd, &msg, resp);
 171 }
 172
 173 /* Send request on fd, wait for response (called by applications, not
 174  * the daemon)
 175  */
 176 void _wapi_daemon_request_response (int fd, WapiHandleRequest *req,
 177                                     WapiHandleResponse *resp)
 178 {
 179         struct msghdr msg={0};
 180         struct iovec iov;
 181
 182         msg.msg_name=NULL;
 183         msg.msg_namelen=0;
 184         msg.msg_iov=&iov;
 185         msg.msg_iovlen=1;
 186         msg.msg_control=NULL;
 187         msg.msg_controllen=0;
 188         msg.msg_flags=0;
 189
 190         iov.iov_base=req;
 191         iov.iov_len=sizeof(WapiHandleRequest);
 192
 193         _wapi_daemon_request_response_internal (fd, &msg, resp);
 194 }
 195
 196 /* Read request on fd (called by the daemon) */
 197 int _wapi_daemon_request (int fd, WapiHandleRequest *req, int *fds,
 198                           gboolean *has_fds)
 199 {
 200         int ret;
 201         struct msghdr msg;
 202         struct iovec iov;
 203         struct cmsghdr *cmsg;
 204         guchar cmsgdata[CMSG_SPACE (sizeof(int)*3)];
 205
 206         msg.msg_name=NULL;
 207         msg.msg_namelen=0;
 208         msg.msg_iov=&iov;
 209         msg.msg_iovlen=1;
 210         msg.msg_control=cmsgdata;
 211         msg.msg_controllen=sizeof(cmsgdata);
 212         msg.msg_flags=0;
 213         iov.iov_base=req;
 214         iov.iov_len=sizeof(WapiHandleRequest);
 215
 216         do {
 217 #ifdef HAVE_MSG_NOSIGNAL
 218                 ret=recvmsg (fd, &msg, MSG_NOSIGNAL);
 219 #else
 220                 ret=recvmsg (fd, &msg, 0);
 221 #endif
 222         }
 223         while (ret==-1 && errno==EINTR);
 224
 225         if(ret==-1 || ret!= sizeof(WapiHandleRequest)) {
 226                 /* Make sure we dont do anything with this response */
 227                 req->type=WapiHandleRequestType_Error;
 228
 229                 g_warning ("%s: Recv error: %s", __func__, strerror (errno));
 230                 /* The next loop around poll() should tidy up */
 231         }
 232
 233 #ifdef DEBUG
 234         if(msg.msg_flags & MSG_OOB) {
 235                 g_message ("%s: OOB data received", __func__);
 236         }
 237         if(msg.msg_flags & MSG_CTRUNC) {
 238                 g_message ("%s: ancillary data was truncated", __func__);
 239         }
 240         g_message ("%s: msg.msg_controllen=%d", __func__, msg.msg_controllen);
 241 #endif
 242
 243         cmsg=CMSG_FIRSTHDR (&msg);
 244         if(cmsg!=NULL && cmsg->cmsg_level==SOL_SOCKET &&
 245            cmsg->cmsg_type==SCM_RIGHTS) {
 246                 LOGDEBUG ("%s: cmsg->cmsg_len=%d", __func__, cmsg->cmsg_len);
 247                 LOGDEBUG ("%s: cmsg->level=%d cmsg->type=%d", __func__, cmsg->cmsg_level, cmsg->cmsg_type);
 248
 249                 memcpy (fds, (int *)CMSG_DATA (cmsg), sizeof(int)*3);
 250                 *has_fds=TRUE;
 251
 252                 LOGDEBUG ("%s: fd[0]=%d, fd[1]=%d, fd[2]=%d", __func__, fds[0], fds[1], fds[2]);
 253         } else {
 254                 LOGDEBUG ("%s: no ancillary data", __func__);
 255                 *has_fds=FALSE;
 256         }
 257
 258         return(ret);
 259 }
 260
 261 /* Send response on fd (called by the daemon) */
 262 int _wapi_daemon_response (int fd, WapiHandleResponse *resp)
 263 {
 264         int ret;
 265
 266         do {
 267 #ifdef HAVE_MSG_NOSIGNAL
 268                 ret=send (fd, resp, sizeof(WapiHandleResponse), MSG_NOSIGNAL);
 269 #else
 270                 ret=send (fd, resp, sizeof(WapiHandleResponse), 0);
 271 #endif
 272         }
 273         while (ret==-1 && errno==EINTR);
 274
 275 #ifdef DEBUG
 276         if(ret==-1 || ret != sizeof(WapiHandleResponse)) {
 277                 g_warning ("%s: Send error: %s", __func__, strerror (errno));
 278                 /* The next loop around poll() should tidy up */
 279         }
 280 #endif
 281
 282         return(ret);
 283 }