contrib/bind-9.3/lib/bind/isc/ev_connects.c

   1 /*
   2  * Copyright (c) 2004 by Internet Systems Consortium, Inc. ("ISC")
   3  * Copyright (c) 1995-1999 by Internet Software Consortium
   4  *
   5  * Permission to use, copy, modify, and distribute this software for any
   6  * purpose with or without fee is hereby granted, provided that the above
   7  * copyright notice and this permission notice appear in all copies.
   8  *
   9  * THE SOFTWARE IS PROVIDED "AS IS" AND ISC DISCLAIMS ALL WARRANTIES
  10  * WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
  11  * MERCHANTABILITY AND FITNESS.  IN NO EVENT SHALL ISC BE LIABLE FOR
  12  * ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
  13  * WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
  14  * ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT
  15  * OF OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
  16  */
  17
  18 /* ev_connects.c - implement asynch connect/accept for the eventlib
  19  * vix 16sep96 [initial]
  20  */
  21
  22 #if !defined(LINT) && !defined(CODECENTER)
  23 static const char rcsid[] = "$Id: ev_connects.c,v 1.4.206.3 2006/03/10 00:17:21 marka Exp $";
  24 #endif
  25
  26 /* Import. */
  27
  28 #include "port_before.h"
  29 #include "fd_setsize.h"
  30
  31 #include <sys/types.h>
  32 #include <sys/socket.h>
  33 #include <sys/ioctl.h>
  34
  35 #include <unistd.h>
  36
  37 #include <isc/eventlib.h>
  38 #include <isc/assertions.h>
  39 #include "eventlib_p.h"
  40
  41 #include "port_after.h"
  42
  43 /* Macros. */
  44
  45 #define GETXXXNAME(f, s, sa, len) ( \
  46         (f((s), (&sa), (&len)) >= 0) ? 0 : \
  47                 (errno != EAFNOSUPPORT && errno != EOPNOTSUPP) ? -1 : ( \
  48                         memset(&(sa), 0, sizeof (sa)), \
  49                         (len) = sizeof (sa), \
  50                         (sa).sa_family = AF_UNIX, \
  51                         0 \
  52                 ) \
  53         )
  54
  55 /* Forward. */
  56
  57 static void     listener(evContext ctx, void *uap, int fd, int evmask);
  58 static void     connector(evContext ctx, void *uap, int fd, int evmask);
  59
  60 /* Public. */
  61
  62 int
  63 evListen(evContext opaqueCtx, int fd, int maxconn,
  64          evConnFunc func, void *uap, evConnID *id)
  65 {
  66         evContext_p *ctx = opaqueCtx.opaque;
  67         evConn *new;
  68         int mode;
  69
  70         OKNEW(new);
  71         new->flags = EV_CONN_LISTEN;
  72         OKFREE(mode = fcntl(fd, F_GETFL, NULL), new);   /* side effect: validate fd. */
  73         /*
  74          * Remember the nonblocking status.  We assume that either evSelectFD
  75          * has not been done to this fd, or that if it has then the caller
  76          * will evCancelConn before they evDeselectFD.  If our assumptions
  77          * are not met, then we might restore the old nonblocking status
  78          * incorrectly.
  79          */
  80         if ((mode & PORT_NONBLOCK) == 0) {
  81 #ifdef USE_FIONBIO_IOCTL
  82                 int on = 1;
  83                 OKFREE(ioctl(fd, FIONBIO, (char *)&on), new);
  84 #else
  85                 OKFREE(fcntl(fd, F_SETFL, mode | PORT_NONBLOCK), new);
  86 #endif
  87                 new->flags |= EV_CONN_BLOCK;
  88         }
  89         OKFREE(listen(fd, maxconn), new);
  90         if (evSelectFD(opaqueCtx, fd, EV_READ, listener, new, &new->file) < 0){
  91                 int save = errno;
  92
  93                 FREE(new);
  94                 errno = save;
  95                 return (-1);
  96         }
  97         new->flags |= EV_CONN_SELECTED;
  98         new->func = func;
  99         new->uap = uap;
 100         new->fd = fd;
 101         if (ctx->conns != NULL)
 102                 ctx->conns->prev = new;
 103         new->prev = NULL;
 104         new->next = ctx->conns;
 105         ctx->conns = new;
 106         if (id)
 107                 id->opaque = new;
 108         return (0);
 109 }
 110
 111 int
 112 evConnect(evContext opaqueCtx, int fd, const void *ra, int ralen,
 113           evConnFunc func, void *uap, evConnID *id)
 114 {
 115         evContext_p *ctx = opaqueCtx.opaque;
 116         evConn *new;
 117
 118         OKNEW(new);
 119         new->flags = 0;
 120         /* Do the select() first to get the socket into nonblocking mode. */
 121         if (evSelectFD(opaqueCtx, fd, EV_MASK_ALL,
 122                        connector, new, &new->file) < 0) {
 123                 int save = errno;
 124
 125                 FREE(new);
 126                 errno = save;
 127                 return (-1);
 128         }
 129         new->flags |= EV_CONN_SELECTED;
 130         if (connect(fd, ra, ralen) < 0 &&
 131             errno != EWOULDBLOCK &&
 132             errno != EAGAIN &&
 133             errno != EINPROGRESS) {
 134                 int save = errno;
 135
 136                 (void) evDeselectFD(opaqueCtx, new->file);
 137                 FREE(new);
 138                 errno = save;
 139                 return (-1);
 140         }
 141         /* No error, or EWOULDBLOCK.  select() tells when it's ready. */
 142         new->func = func;
 143         new->uap = uap;
 144         new->fd = fd;
 145         if (ctx->conns != NULL)
 146                 ctx->conns->prev = new;
 147         new->prev = NULL;
 148         new->next = ctx->conns;
 149         ctx->conns = new;
 150         if (id)
 151                 id->opaque = new;
 152         return (0);
 153 }
 154
 155 int
 156 evCancelConn(evContext opaqueCtx, evConnID id) {
 157         evContext_p *ctx = opaqueCtx.opaque;
 158         evConn *this = id.opaque;
 159         evAccept *acc, *nxtacc;
 160         int mode;
 161
 162         if ((this->flags & EV_CONN_SELECTED) != 0)
 163                 (void) evDeselectFD(opaqueCtx, this->file);
 164         if ((this->flags & EV_CONN_BLOCK) != 0) {
 165                 mode = fcntl(this->fd, F_GETFL, NULL);
 166                 if (mode == -1) {
 167                         if (errno != EBADF)
 168                                 return (-1);
 169                 } else {
 170 #ifdef USE_FIONBIO_IOCTL
 171                         int off = 0;
 172                         OK(ioctl(this->fd, FIONBIO, (char *)&off));
 173 #else
 174                         OK(fcntl(this->fd, F_SETFL, mode & ~PORT_NONBLOCK));
 175 #endif
 176                 }
 177         }
 178
 179         /* Unlink from ctx->conns. */
 180         if (this->prev != NULL)
 181                 this->prev->next = this->next;
 182         else
 183                 ctx->conns = this->next;
 184         if (this->next != NULL)
 185                 this->next->prev = this->prev;
 186
 187         /*
 188          * Remove `this' from the ctx->accepts list (zero or more times).
 189          */
 190         for (acc = HEAD(ctx->accepts), nxtacc = NULL;
 191              acc != NULL;
 192              acc = nxtacc)
 193         {
 194                 nxtacc = NEXT(acc, link);
 195                 if (acc->conn == this) {
 196                         UNLINK(ctx->accepts, acc, link);
 197                         close(acc->fd);
 198                         FREE(acc);
 199                 }
 200         }
 201
 202         /* Wrap up and get out. */
 203         FREE(this);
 204         return (0);
 205 }
 206
 207 int evHold(evContext opaqueCtx, evConnID id) {
 208         evConn *this = id.opaque;
 209
 210         if ((this->flags & EV_CONN_LISTEN) == 0) {
 211                 errno = EINVAL;
 212                 return (-1);
 213         }
 214         if ((this->flags & EV_CONN_SELECTED) == 0)
 215                 return (0);
 216         this->flags &= ~EV_CONN_SELECTED;
 217         return (evDeselectFD(opaqueCtx, this->file));
 218 }
 219
 220 int evUnhold(evContext opaqueCtx, evConnID id) {
 221         evConn *this = id.opaque;
 222         int ret;
 223
 224         if ((this->flags & EV_CONN_LISTEN) == 0) {
 225                 errno = EINVAL;
 226                 return (-1);
 227         }
 228         if ((this->flags & EV_CONN_SELECTED) != 0)
 229                 return (0);
 230         ret = evSelectFD(opaqueCtx, this->fd, EV_READ, listener, this,
 231                          &this->file);
 232         if (ret == 0)
 233                 this->flags |= EV_CONN_SELECTED;
 234         return (ret);
 235 }
 236
 237 int
 238 evTryAccept(evContext opaqueCtx, evConnID id, int *sys_errno) {
 239         evContext_p *ctx = opaqueCtx.opaque;
 240         evConn *conn = id.opaque;
 241         evAccept *new;
 242
 243         if ((conn->flags & EV_CONN_LISTEN) == 0) {
 244                 errno = EINVAL;
 245                 return (-1);
 246         }
 247         OKNEW(new);
 248         new->conn = conn;
 249         new->ralen = sizeof new->ra;
 250         new->fd = accept(conn->fd, &new->ra.sa, &new->ralen);
 251         if (new->fd > ctx->highestFD) {
 252                 close(new->fd);
 253                 new->fd = -1;
 254                 new->ioErrno = ENOTSOCK;
 255         }
 256         if (new->fd >= 0) {
 257                 new->lalen = sizeof new->la;
 258                 if (GETXXXNAME(getsockname, new->fd, new->la.sa, new->lalen) < 0) {
 259                         new->ioErrno = errno;
 260                         (void) close(new->fd);
 261                         new->fd = -1;
 262                 } else
 263                         new->ioErrno = 0;
 264         } else {
 265                 new->ioErrno = errno;
 266                 if (errno == EAGAIN || errno == EWOULDBLOCK) {
 267                         FREE(new);
 268                         return (-1);
 269                 }
 270         }
 271         INIT_LINK(new, link);
 272         APPEND(ctx->accepts, new, link);
 273         *sys_errno = new->ioErrno;
 274         return (0);
 275 }
 276
 277 /* Private. */
 278
 279 static void
 280 listener(evContext opaqueCtx, void *uap, int fd, int evmask) {
 281         evContext_p *ctx = opaqueCtx.opaque;
 282         evConn *conn = uap;
 283         union {
 284                 struct sockaddr    sa;
 285                 struct sockaddr_in in;
 286 #ifndef NO_SOCKADDR_UN
 287                 struct sockaddr_un un;
 288 #endif
 289         } la, ra;
 290         int new;
 291         ISC_SOCKLEN_T lalen = 0, ralen;
 292
 293         REQUIRE((evmask & EV_READ) != 0);
 294         ralen = sizeof ra;
 295         new = accept(fd, &ra.sa, &ralen);
 296         if (new > ctx->highestFD) {
 297                 close(new);
 298                 new = -1;
 299                 errno = ENOTSOCK;
 300         }
 301         if (new >= 0) {
 302                 lalen = sizeof la;
 303                 if (GETXXXNAME(getsockname, new, la.sa, lalen) < 0) {
 304                         int save = errno;
 305
 306                         (void) close(new);
 307                         errno = save;
 308                         new = -1;
 309                 }
 310         } else if (errno == EAGAIN || errno == EWOULDBLOCK)
 311                 return;
 312         (*conn->func)(opaqueCtx, conn->uap, new, &la.sa, lalen, &ra.sa, ralen);
 313 }
 314
 315 static void
 316 connector(evContext opaqueCtx, void *uap, int fd, int evmask) {
 317         evConn *conn = uap;
 318         union {
 319                 struct sockaddr    sa;
 320                 struct sockaddr_in in;
 321 #ifndef NO_SOCKADDR_UN
 322                 struct sockaddr_un un;
 323 #endif
 324         } la, ra;
 325         ISC_SOCKLEN_T lalen, ralen;
 326 #ifndef NETREAD_BROKEN
 327         char buf[1];
 328 #endif
 329         void *conn_uap;
 330         evConnFunc conn_func;
 331         evConnID id;
 332         int socket_errno = 0;
 333         ISC_SOCKLEN_T optlen;
 334
 335         UNUSED(evmask);
 336
 337         lalen = sizeof la;
 338         ralen = sizeof ra;
 339         conn_uap = conn->uap;
 340         conn_func = conn->func;
 341         id.opaque = conn;
 342 #ifdef SO_ERROR
 343         optlen = sizeof socket_errno;
 344         if (fd < 0 &&
 345             getsockopt(conn->fd, SOL_SOCKET, SO_ERROR, (char *)&socket_errno,
 346                        &optlen) < 0)
 347                 socket_errno = errno;
 348         else
 349                 errno = socket_errno;
 350 #endif
 351         if (evCancelConn(opaqueCtx, id) < 0 ||
 352             socket_errno ||
 353 #ifdef NETREAD_BROKEN
 354             0 ||
 355 #else
 356             read(fd, buf, 0) < 0 ||
 357 #endif
 358             GETXXXNAME(getsockname, fd, la.sa, lalen) < 0 ||
 359             GETXXXNAME(getpeername, fd, ra.sa, ralen) < 0) {
 360                 int save = errno;
 361
 362                 (void) close(fd);       /* XXX closing caller's fd */
 363                 errno = save;
 364                 fd = -1;
 365         }
 366         (*conn_func)(opaqueCtx, conn_uap, fd, &la.sa, lalen, &ra.sa, ralen);
 367 }