tcp.c

   1 /*
   2  * Copyright (c) 2004 Teodor Sigaev <teodor@sigaev.ru>
   3  * All rights reserved.
   4  *
   5  * Redistribution and use in source and binary forms, with or without
   6  * modification, are permitted provided that the following conditions
   7  * are met:
   8  * 1. Redistributions of source code must retain the above copyright
   9  *        notice, this list of conditions and the following disclaimer.
  10  * 2. Redistributions in binary form must reproduce the above copyright
  11  *        notice, this list of conditions and the following disclaimer in the
  12  *        documentation and/or other materials provided with the distribution.
  13  * 3. Neither the name of the author nor the names of any co-contributors
  14  *        may be used to endorse or promote products derived from this software
  15  *        without specific prior written permission.
  16  *
  17  * THIS SOFTWARE IS PROVIDED BY CONTRIBUTORS ``AS IS'' AND ANY EXPRESS
  18  * OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED
  19  * WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
  20  * ARE DISCLAIMED. IN NO EVENT SHALL CONTRIBUTORS BE LIABLE FOR ANY
  21  * DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
  22  * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE
  23  * GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS
  24  * INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER
  25  * IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR
  26  * OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS SOFTWARE, EVEN
  27  * IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  28  */
  29 #include <stdio.h>
  30 #include <errno.h>
  31 #include <stdlib.h>
  32 #include <string.h>
  33 #include <unistd.h>
  34 #include <fcntl.h>
  35
  36 #ifdef HAVE_POLL_H
  37 #include <poll.h>
  38 #else /* HAVE_POLL */
  39 #ifdef HAVE_SYS_POLL_H
  40 #include <sys/poll.h>
  41 #else
  42 #error Not defined HAVE_POLL_H or HAVE_SYS_POLL_H
  43 #endif /* HAVE_SYS_POLL_H */
  44 #endif /* HAVE_POLL */
  45
  46 #ifdef HAVE_HSTRERROR
  47 #include <netdb.h>
  48 #endif
  49
  50
  51 #include "connection.h"
  52 #include "tlog.h"
  53 #include "tmalloc.h"
  54
  55 static u_int32_t
  56 setlinger( TC_Connection *cs ) {
  57         struct linger ling;
  58         int     val = 0;
  59         socklen_t size = sizeof(val);
  60
  61         if (getsockopt(cs->fd, SOL_SOCKET,SO_ERROR,&val,&size) == -1) {
  62                 tlog(TL_ALARM,"getsockopt: %s:%d - %s(%d)",inet_ntoa(cs->serv_addr.sin_addr),
  63                         ntohs(cs->serv_addr.sin_port), strerror(errno), errno);
  64                 shutdown(cs->fd,SHUT_RDWR);
  65                 close(cs->fd);
  66                 cs->fd = 0;
  67                 cs->state = CS_ERROR;
  68                 return CS_ERROR;
  69         }
  70
  71         if ( val ) {
  72                 tlog(TL_ALARM,"getsockopt return: %s:%d - %s(%d)",inet_ntoa(cs->serv_addr.sin_addr),
  73                         ntohs(cs->serv_addr.sin_port), strerror(val), val);
  74                 shutdown(cs->fd,SHUT_RDWR);
  75                 close(cs->fd);
  76                 cs->fd = 0;
  77                 cs->state = CS_ERROR;
  78                 return CS_ERROR;
  79         }
  80
  81
  82         ling.l_onoff = ling.l_linger = 0;
  83         if (setsockopt(cs->fd, SOL_SOCKET,SO_LINGER,(char *)&ling,sizeof(ling))==-1) {
  84                 tlog(TL_ALARM,"setsockopt: LINGER %s:%d - %s",inet_ntoa(cs->serv_addr.sin_addr), ntohs(cs->serv_addr.sin_port),
  85                         strerror(errno));
  86                 shutdown(cs->fd,SHUT_RDWR);
  87                 close(cs->fd);
  88                 cs->fd = 0;
  89                 cs->state = CS_ERROR;
  90                 return CS_ERROR;
  91         }
  92         cs->state = CS_CONNECTED;
  93         return CS_CONNECTED;
  94 }
  95
  96 u_int32_t
  97 TC_ClientInitConnection(TC_Connection *cs, char *name, u_int32_t port) {
  98         int flags, val=1;
  99
 100         cs = TC_fillConnection(cs, name, port);
 101
 102         cs->state = CS_OK;
 103         if ((cs->fd= socket(AF_INET, SOCK_STREAM, 0)) < 0)
 104                 tlog(TL_CRIT|TL_EXIT,"socket4: %s:%d - %s",inet_ntoa(cs->serv_addr.sin_addr),
 105                         ntohs(cs->serv_addr.sin_port),strerror(errno));
 106
 107         if (setsockopt(cs->fd, SOL_SOCKET, SO_REUSEADDR, &val, sizeof(val)) < 0) {
 108                 tlog(TL_CRIT|TL_EXIT, "socketsockopt failed: %s", strerror(errno));
 109                 return CS_ERROR;
 110         }
 111
 112         if ((flags=fcntl(cs->fd,F_GETFL,0)) == -1)
 113                 tlog(TL_ALARM,"fcntl F_GETFL - %s",strerror(errno));
 114         if (fcntl(cs->fd,F_SETFL,flags|O_NDELAY) < 0 )
 115                 tlog(TL_ALARM,"fcntl O_NDELAY - %s",strerror(errno));
 116
 117         if (bind(cs->fd, (struct sockaddr *) &(cs->serv_addr), sizeof(cs->serv_addr)) < 0)
 118                 tlog(TL_CRIT|TL_EXIT, "cannot bind to %s address: %s",
 119                         inet_ntoa(cs->serv_addr.sin_addr), strerror(errno));
 120
 121         if (listen(cs->fd, 0) < 0)
 122                 tlog(TL_CRIT|TL_EXIT, "cannot listen to %s address: %s",
 123                         inet_ntoa(cs->serv_addr.sin_addr), strerror(errno));
 124
 125         return CS_OK;
 126 }
 127
 128 TC_Connection*
 129 TC_AcceptTcp(TC_Connection *cs) {
 130         TC_Connection *nc;
 131         struct sockaddr_in cli_addr;
 132         int ret, flags;
 133         socklen_t clilen = sizeof(cli_addr);
 134
 135         cs->state = CS_READ;
 136         if ( (ret = accept(cs->fd,(struct sockaddr *)&cli_addr, &clilen)) < 0 ) {
 137                 if ( errno == EAGAIN || errno == EWOULDBLOCK )
 138                         return NULL;
 139                 tlog(TL_ALARM,"TC_AcceptTcp: accept: %s", strerror(errno));
 140                 return NULL;
 141         }
 142         nc = (TC_Connection*)t0malloc(sizeof(TC_Connection));
 143
 144         nc->fd = ret;
 145         if ((flags=fcntl(nc->fd,F_GETFL,0)) == -1)
 146                 tlog(TL_ALARM,"fcntl F_GETFL - %s",strerror(errno));
 147         if (fcntl(nc->fd,F_SETFL,flags|O_NDELAY) < 0 )
 148                 tlog(TL_ALARM,"fcntl O_NDELAY - %s",strerror(errno));
 149         memcpy( &(nc->serv_addr), &cli_addr, clilen );
 150         nc->state = CS_CONNECTED;
 151
 152         setlinger(nc);
 153         return nc;
 154 }
 155
 156 TC_Connection *
 157 TC_fillConnection(TC_Connection *sc, char *name, u_int32_t port) {
 158         if ( !sc )
 159                 sc = (TC_Connection *)t0malloc(sizeof(TC_Connection));
 160         sc->serv_addr.sin_family = AF_INET;
 161         sc->serv_addr.sin_addr.s_addr = (name) ? inet_addr(name) : htonl(INADDR_ANY);
 162         sc->serv_addr.sin_port = htons(port);
 163         sc->state = CS_NOTINITED;
 164         return sc;
 165 }
 166
 167
 168 u_int32_t
 169 TC_ServerInitConnect( TC_Connection     *cs ) {
 170         int flags;
 171
 172         if ( cs->state == CS_ERROR )
 173                 return CS_ERROR;
 174
 175         if ((cs->fd= socket(AF_INET, SOCK_STREAM, 0)) < 0) {
 176                 tlog(TL_CRIT,"socket4: %s:%d - %s",inet_ntoa(cs->serv_addr.sin_addr),
 177                         ntohs(cs->serv_addr.sin_port),strerror(errno));
 178                 cs->state  = CS_ERROR;
 179                 return  CS_ERROR;
 180         }
 181
 182         if ((flags=fcntl(cs->fd,F_GETFL,0)) == -1)
 183                 tlog(TL_ALARM,"fcntl F_GETFL - %s",strerror(errno));
 184         if (fcntl(cs->fd,F_SETFL,flags|O_NDELAY) < 0 )
 185                 tlog(TL_ALARM,"fcntl O_NDELAY - %s",strerror(errno));
 186
 187         if ( connect(cs->fd, (struct sockaddr *) &(cs->serv_addr),
 188                 sizeof(struct sockaddr_in)) < 0 ) {
 189                 if ( errno == EINPROGRESS || errno == EALREADY ) {
 190                         cs->state = CS_INPROCESS;
 191                         return CS_INPROCESS;
 192                 } else if (errno != EISCONN && errno != EALREADY &&
 193                         errno != EWOULDBLOCK && errno != EAGAIN) {
 194                         tlog(TL_DEBUG,"open4: %s:%d - %s",
 195                                 inet_ntoa(cs->serv_addr.sin_addr), ntohs(cs->serv_addr.sin_port),
 196                                 strerror(errno));
 197                         shutdown(cs->fd,SHUT_RDWR);
 198                         close(cs->fd);
 199                         cs->fd = 0;
 200                 } else {
 201                         tlog(TL_DEBUG,"nonblock connect: %s:%d - %s [%d]",
 202                                 inet_ntoa(cs->serv_addr.sin_addr),
 203                                 ntohs(cs->serv_addr.sin_port),
 204                                 strerror(errno),errno);
 205                 }
 206                 cs->state = CS_ERROR;
 207                 return CS_ERROR;
 208         }
 209
 210         cs->state = CS_INPROCESS;
 211         return TC_ServerConnect( cs );
 212 }
 213
 214
 215 u_int32_t
 216 TC_ServerConnect( TC_Connection *cs ) {
 217         fd_set  fdwr, fdexcept;
 218         int ret;
 219         struct timeval timeout;
 220
 221         if ( cs->state != CS_INPROCESS )
 222                 return cs->state;
 223
 224         FD_ZERO( &fdwr );
 225         FD_ZERO( &fdexcept );
 226
 227         FD_SET(cs->fd, &fdwr);
 228         FD_SET(cs->fd, &fdexcept);
 229
 230         memset( &timeout, 0, sizeof(struct timeval));
 231
 232         ret = select( cs->fd+1, NULL, &fdwr, &fdexcept, &timeout ) ;
 233         if ( ret<0 ) {
 234                 tlog( TL_CRIT, "TC_ServerConnect: select: %s",
 235                         strerror(errno));
 236                 cs->state = CS_ERROR;
 237                 return CS_ERROR;
 238         } else if ( ret == 0 )
 239                 return CS_INPROCESS;
 240
 241         if ( FD_ISSET(cs->fd, &fdexcept) ) {
 242                 tlog( TL_CRIT, "TC_ServerConnect: select return connect error for %s:%d",
 243                         inet_ntoa(cs->serv_addr.sin_addr), ntohs(cs->serv_addr.sin_port));
 244                 cs->state = CS_ERROR;
 245                 return CS_ERROR;
 246         }
 247
 248         if ( ! FD_ISSET(cs->fd, &fdwr) )
 249                 return CS_INPROCESS;
 250
 251
 252         return setlinger( cs );
 253 }
 254
 255 int
 256 TC_ReadyIO( TC_Connection **cs, int number, int timeout ) {
 257         struct pollfd   *pfd;
 258         int ret,i, fdnum=0;
 259
 260         if ( number==0 || cs ==NULL ) {
 261                 usleep( timeout * 1000.0 );
 262                 return 0;
 263         }
 264         pfd = (struct pollfd*) tmalloc( sizeof(struct pollfd) * number );
 265
 266         for(i=0; i<number;i++) {
 267                 if ( cs[i]->fd>0 && (cs[i]->state == CS_READ || cs[i]->state == CS_SEND) ) {
 268                         pfd[fdnum].fd = cs[i]->fd;
 269                         pfd[fdnum].events = ( cs[i]->state == CS_READ ) ? POLLIN : POLLOUT;
 270                         pfd[fdnum].revents = 0;
 271                         fdnum++;
 272                 }
 273                 cs[i]->readyio=0;
 274         }
 275         ret = poll( pfd, fdnum, timeout );
 276         if ( ret<0 ) {
 277                 tlog( TL_CRIT, "TC_ReadyIO: poll: %s",
 278                         strerror(errno));
 279                 tfree(pfd);
 280                 return 0;
 281         }
 282
 283         if ( ret == 0 ) {
 284                 tfree(pfd);
 285                 return 0;
 286         }
 287
 288         fdnum=0; ret=0;
 289         for(i=0; i<number;i++) {
 290                 if ( cs[i]->fd>0 && (cs[i]->state == CS_READ || cs[i]->state == CS_SEND) ) {
 291                         if ( pfd[fdnum].revents & (POLLHUP | POLLNVAL | POLLERR) ) {
 292                                 tlog( TL_ALARM, "TC_ReadyIO: poll return error for %s:%d",
 293                                         inet_ntoa(cs[i]->serv_addr.sin_addr),
 294                                         ntohs(cs[i]->serv_addr.sin_port));
 295                                 cs[i]->state = CS_ERROR;
 296                                 ret = 1;
 297                         } else if ( pfd[fdnum].revents & ( ( cs[i]->state == CS_READ ) ? POLLIN : POLLOUT ) ) {
 298                                 cs[i]->readyio=1;
 299                                 ret = 1;
 300                         }
 301                         fdnum++;
 302                 }
 303         }
 304
 305         tfree(pfd);
 306         return ret;
 307 }
 308
 309 u_int32_t
 310 TC_Send( TC_Connection *cs ) {
 311         int sz;
 312
 313         if ( cs->state == CS_ERROR )
 314                 return CS_ERROR;
 315
 316         if ( cs->state != CS_SEND ) {
 317                 cs->state = CS_SEND;
 318                 cs->ptr = cs->buf;
 319         }
 320
 321         if ( cs->ptr - cs->buf >= cs->len ) {
 322                 cs->state = CS_FINISHSEND;
 323                 return CS_FINISHSEND;
 324         }
 325
 326         if ((sz=write(cs->fd, cs->ptr, cs->len - (cs->ptr - cs->buf)))==0 ||
 327                 (sz < 0 && (errno == EWOULDBLOCK || errno == EAGAIN))) {
 328
 329                 /* SunOS 4.1.x, are broken and select() says that
 330                  * O_NDELAY sockets are always writable even when
 331                  * they're actually not.
 332                  */
 333                 cs->state = CS_SEND;
 334                 return CS_SEND;
 335         }
 336         if ( sz<0 ) {
 337                 if (errno != EPIPE && errno != EINVAL)
 338                         tlog(TL_ALARM, "write[%s:%d] - %s",
 339                                 inet_ntoa(cs->serv_addr.sin_addr),
 340                                 ntohs(cs->serv_addr.sin_port),
 341                                 strerror(errno));
 342                 cs->state = CS_ERROR;
 343                 return CS_ERROR;
 344         }
 345
 346         cs->ptr += sz;
 347
 348         if ( cs->ptr - cs->buf >= cs->len ) {
 349                 cs->state = CS_FINISHSEND;
 350                 return CS_FINISHSEND;
 351         }
 352
 353         return cs->state;
 354 }
 355
 356 static void
 357 resizeCS( TC_Connection *cs, int sz ) {
 358         int diff = cs->ptr - cs->buf;
 359         if ( cs->len >= sz )
 360                 return;
 361         cs->len = sz;
 362         cs->buf = (char*)trealloc( (void*)cs->buf, cs->len );
 363         cs->ptr = cs->buf + diff;
 364 }
 365
 366 u_int32_t
 367 TC_Read( TC_Connection *cs ) {
 368         int sz, totalread = -1, toread=0, alreadyread;
 369
 370         if ( cs->state == CS_ERROR )
 371                 return CS_ERROR;
 372
 373         if (cs->state != CS_READ ) {
 374                 cs->state = CS_READ;
 375                 cs->ptr = cs->buf;
 376         }
 377
 378         alreadyread = cs->ptr - cs->buf;
 379         if ( alreadyread < sizeof(u_int32_t) ) {
 380                 toread = sizeof(u_int32_t) - alreadyread;
 381                 resizeCS(cs, sizeof(u_int32_t));
 382         } else {
 383                 totalread = *(u_int32_t*)(cs->buf);
 384                 toread = totalread - alreadyread;
 385                 if ( toread == 0 ) {
 386                         cs->state = CS_FINISHREAD;
 387                         return CS_FINISHREAD;
 388                 }
 389                 resizeCS(cs, totalread);
 390         }
 391
 392         if ((sz=read( cs->fd, cs->ptr, toread))<0) {
 393                 if (errno == EAGAIN || errno == EINTR) {
 394                         cs->state = CS_READ;
 395                         return CS_READ;
 396                 }
 397                 tlog(TL_ALARM,"read: finish - %s",strerror(errno));
 398                 cs->state = CS_ERROR;
 399                 return CS_ERROR;
 400         }
 401
 402
 403         cs->ptr += sz;
 404         alreadyread += sz;
 405         if ( sz == 0 && alreadyread != totalread ) {
 406                 tlog(TL_ALARM,"read: disconnecting");
 407                 cs->state = CS_ERROR;
 408                 return CS_ERROR;
 409         }
 410         cs->state = ( alreadyread == totalread ) ? CS_FINISHREAD : CS_READ;
 411         return cs->state;
 412 }
 413
 414 void
 415 TC_FreeConnection( TC_Connection *cs ) {
 416         if ( cs->state == CS_CLOSED )
 417                 return;
 418         if ( cs->buf ) {
 419                 tfree(cs->buf);
 420                 cs->buf = NULL;
 421         }
 422         if ( cs->fd && cs->state != CS_NOTINITED ) {
 423                 shutdown(cs->fd,SHUT_RDWR);
 424                 close(cs->fd);
 425         }
 426         cs->fd = 0;
 427         cs->state = CS_CLOSED;
 428 }
 429
 430 u_int32_t
 431 TC_Talk( TC_Connection *cs ) {
 432         u_int32_t ret = TC_ServerInitConnect( cs );
 433
 434         while( ret == CS_INPROCESS ) {
 435                 ret =  TC_ServerConnect(cs);
 436         }
 437
 438         if ( ret != CS_CONNECTED )
 439                 return ret;
 440
 441         while( ret != CS_FINISHSEND ) {
 442                 ret = TC_Send(cs);
 443                 if ( ret == CS_ERROR ) return ret;
 444         }
 445
 446         cs->state = CS_READ;
 447         cs->ptr = cs->buf;
 448         while( cs->state != CS_FINISHREAD ) {
 449                 while( !TC_ReadyIO( &cs, 1, 100) );
 450                 if ( TC_Read(cs) == CS_ERROR ) return CS_ERROR;
 451         }
 452
 453         return CS_OK;
 454 }
 455
 456