commands/ftpd200/net.c

   1 /* net.c Copyright 1992-2000 by Michael Temari All Rights Reserved
   2  *
   3  * This file is part of ftpd.
   4  *
   5  * This file handles:
   6  *
   7  *      PASV PORT
   8  *
   9  *
  10  * 01/25/1995 Initial Release   Michael Temari, <Michael@TemWare.Com>
  11  * 02/09/2005 Initial Release   Michael Temari, <Michael@TemWare.Com>
  12  */
  13
  14 #include <sys/types.h>
  15 #include <sys/ioctl.h>
  16 #include <sys/wait.h>
  17 #include <stdio.h>
  18 #include <stdlib.h>
  19 #include <string.h>
  20 #include <errno.h>
  21 #include <fcntl.h>
  22 #include <signal.h>
  23 #include <unistd.h>
  24 #include <time.h>
  25 #include <net/netlib.h>
  26 #include <net/hton.h>
  27 #include <net/gen/in.h>
  28 #include <net/gen/inet.h>
  29 #include <net/gen/tcp.h>
  30 #include <net/gen/tcp_io.h>
  31 #include <net/gen/socket.h>
  32 #include <net/gen/netdb.h>
  33
  34 #include "ftpd.h"
  35 #include "access.h"
  36 #include "net.h"
  37
  38 _PROTOTYPE(static void timeout, (int sig));
  39
  40 static char *msg425 = "425-Could not open data connection.\r\n";
  41 static char *msg501 = "501 Syntax error in parameters.\r\n";
  42
  43 static int gottimeout = 0;
  44 static int lpid = -1;
  45 static int didpassive = 0;
  46
  47 /* they must be behind a firewall or using a web browser */
  48 int doPASV(buff)
  49 char *buff;
  50 {
  51 nwio_tcpconf_t tcpconf;
  52 nwio_tcpcl_t tcplopt;
  53 char *tcp_device;
  54 ipaddr_t ipaddr;
  55 tcpport_t lport;
  56 int s;
  57 time_t starttime;
  58 int retry;
  59
  60    if(ChkLoggedIn())
  61         return(GOOD);
  62
  63    CleanUpPasv();
  64
  65    /* here we set up a connection to listen on */
  66    if((tcp_device = getenv("TCP_DEVICE")) == NULL)
  67         tcp_device = TCP_DEVICE;
  68
  69    if(ftpdata_fd >= 0) {
  70         close(ftpdata_fd);
  71         ftpdata_fd = -1;
  72    }
  73
  74    if((ftpdata_fd = open(tcp_device, O_RDWR)) < 0) {
  75         printf(msg425);
  76         printf("425 Could not open tcp_device.  Error %s\r\n", strerror(errno));
  77         return(GOOD);
  78    }
  79
  80    tcpconf.nwtc_flags = NWTC_LP_SEL | NWTC_SET_RA | NWTC_UNSET_RP;
  81
  82    tcpconf.nwtc_remaddr = rmtipaddr;
  83    tcpconf.nwtc_remport = htons(0);
  84    tcpconf.nwtc_locport = htons(0);
  85
  86    s = ioctl(ftpdata_fd, NWIOSTCPCONF, &tcpconf);
  87    if(s < 0) {
  88         printf(msg425);
  89         printf("425 Could not ioctl NWIOSTCPCONF. Error %s\r\n", strerror(errno));
  90         close(ftpdata_fd);
  91         ftpdata_fd = -1;
  92         return(GOOD);
  93    }
  94
  95    s = ioctl(ftpdata_fd, NWIOGTCPCONF, &tcpconf);
  96    if(s < 0) {
  97         printf(msg425);
  98         printf("425 Could not NWIOGTCPCONF. Error %s\r\n", strerror(errno));
  99         close(ftpdata_fd);
 100         ftpdata_fd = -1;
 101         return(GOOD);
 102    }
 103    ipaddr = tcpconf.nwtc_locaddr;
 104    lport = tcpconf.nwtc_locport;
 105
 106    /* Now lets fork a child to do the listening :-( */
 107
 108    tcplopt.nwtcl_flags = 0;
 109
 110    lpid = fork();
 111    if(lpid < 0) {
 112         printf(msg425);
 113         printf("425 Could not fork listener.  Error %s\r\n", strerror(errno));
 114         close(ftpdata_fd);
 115         ftpdata_fd = -1;
 116         return(GOOD);
 117    } else if(lpid == 0) {
 118         retry = 0;
 119         while(1) {
 120 #ifdef DEBUG
 121                 fprintf(logfile, "ftpd: child %d  parent %d  listen try %d\n", getpid(), getppid(), retry);
 122                 fflush(logfile);
 123 #endif
 124                 s = ioctl(ftpdata_fd, NWIOTCPLISTEN, &tcplopt);
 125                 if(!(s == -1 && errno == EAGAIN)) break;
 126                 if(retry++ > 10) break;
 127                 sleep(1);
 128         }
 129 #ifdef DEBUG
 130         fprintf(logfile, "ftpd: child %d  s %d  errno %d\n", getpid(), s, errno);
 131         fflush(logfile);
 132 #endif
 133         if(s < 0)
 134                 exit(errno);    /* tells parent listen failed */
 135         else
 136                 exit(0);        /* tells parent listen okay */
 137    }
 138
 139 #ifdef DEBUG
 140    fprintf(logfile, "ftpd: parent %d  wait for %d\n", getpid(), lpid);
 141    fflush(logfile);
 142 #endif
 143
 144    /* wait for child to be listening, no more than serveral seconds */
 145    (void) time(&starttime);
 146    while(1) {
 147         if(time((time_t *)NULL) > (starttime + 15)) break;
 148         signal(SIGALRM, timeout);
 149         alarm(1);
 150         s = ioctl(ftpdata_fd, NWIOGTCPCONF, &tcpconf);
 151 #ifdef DEBUG
 152         fprintf(logfile, "ftpd: parent %d  child %d  s %d  errno %d start %ld  now %ld\n",
 153                 getpid(), lpid, s, errno, starttime, time((time_t *)NULL));
 154         fflush(logfile);
 155 #endif
 156         alarm(0);
 157         if(s == -1) break;
 158         sleep(1);
 159    }
 160
 161 #define hiword(x)       ((u16_t)((x) >> 16))
 162 #define loword(x)       ((u16_t)(x & 0xffff))
 163 #define hibyte(x)       (((x) >> 8) & 0xff)
 164 #define lobyte(x)       ((x) & 0xff)
 165
 166    printf("227 Entering Passive Mode (%u,%u,%u,%u,%u,%u).\r\n",
 167                 hibyte(hiword(htonl(ipaddr))), lobyte(hiword(htonl(ipaddr))),
 168                 hibyte(loword(htonl(ipaddr))), lobyte(loword(htonl(ipaddr))),
 169                 hibyte(htons(lport)), lobyte(htons(lport)));
 170
 171 #ifdef DEBUG
 172    fprintf(logfile, "ftpd: parent %d  child %d  send 227\n", getpid(), lpid);
 173    fflush(logfile);
 174 #endif
 175
 176    didpassive = -1;
 177
 178    return(GOOD);
 179 }
 180
 181 /* they want us to connect here */
 182 int doPORT(buff)
 183 char *buff;
 184 {
 185 u32_t ipaddr;
 186 u16_t port;
 187 int i;
 188
 189    if(ftpdata_fd >= 0) {
 190         close(ftpdata_fd);
 191         ftpdata_fd = -1;
 192    }
 193
 194    ipaddr = (u32_t)0;
 195    for(i = 0; i < 4; i++) {
 196         ipaddr = (ipaddr << 8) + (u32_t)atoi(buff);
 197         if((buff = strchr(buff, ',')) == (char *)0) {
 198                 printf(msg501);
 199                 return(GOOD);
 200         }
 201         buff++;
 202    }
 203    port = (u16_t)atoi(buff);
 204    if((buff = strchr(buff, ',')) == (char *)0) {
 205         printf(msg501);
 206         return(0);
 207    }
 208    buff++;
 209    port = (port << 8) + (u16_t)atoi(buff);
 210
 211    dataaddr = htonl(ipaddr);
 212    dataport = htons(port);
 213    if(dataaddr != rmtipaddr) {
 214         printf(msg501);
 215         return(GOOD);
 216    }
 217
 218    printf("200 Port command okay.\r\n");
 219
 220    return(GOOD);
 221 }
 222
 223 /* connect, huh? */
 224 int DataConnect()
 225 {
 226 nwio_tcpconf_t tcpconf;
 227 nwio_tcpcl_t tcpcopt;
 228 nwio_tcpcl_t tcplopt;
 229 char *tcp_device;
 230 int s, cs;
 231 int retry;
 232
 233    if(didpassive && ftpdata_fd >= 0) {
 234         didpassive = 0;
 235         gottimeout = 0;
 236         signal(SIGALRM, timeout);
 237         alarm(10);
 238         while(!gottimeout) {
 239                 s = waitpid(lpid, &cs, 0);
 240                 if((s == lpid) || (s < 0 && errno == ECHILD)) break;
 241 #ifdef DEBUG
 242                 fprintf(logfile, "ftpd: parent %d  child %d waitpid s %d  cs %04x  errno %d\n", getpid(), lpid, s, cs, errno);
 243                 fflush(logfile);
 244 #endif
 245         }
 246         alarm(0);
 247 #ifdef DEBUG
 248         fprintf(logfile, "ftpd: parent %d  child %d waitpid s %d  cs %04x  errno %d\n", getpid(), lpid, s, cs, errno);
 249                 fflush(logfile);
 250 #endif
 251         if(gottimeout) {
 252 #ifdef DEBUG
 253                 fprintf(logfile, "ftpd: parent %d  child %d  got timeout\n", getpid(), lpid);
 254                 fflush(logfile);
 255 #endif
 256                 kill(lpid, SIGKILL);
 257                 s = waitpid(lpid, &cs, 0);
 258         }
 259 #ifdef DEBUG
 260         fprintf(logfile, "ftpd: parent %d  child %d continuing\n", getpid(), lpid);
 261         fflush(logfile);
 262 #endif
 263         lpid = -1;
 264         if(gottimeout) {
 265                 printf(msg425);
 266                 printf("425 Child listener timeout.\r\n");
 267                 close(ftpdata_fd);
 268                 ftpdata_fd = -1;
 269                 return(BAD);
 270         }
 271         if(s < 0) {
 272                 printf(msg425);
 273                 printf("425 Child listener vanished.\r\n");
 274                 close(ftpdata_fd);
 275                 ftpdata_fd = -1;
 276                 return(BAD);
 277         }
 278         if((cs & 0x00ff)) {
 279                 printf(msg425);
 280                 printf("425 Child listener failed %04x\r\n", cs);
 281                 close(ftpdata_fd);
 282                 ftpdata_fd = -1;
 283                 return(BAD);
 284         }
 285         cs = (cs >> 8) & 0x00ff;
 286         if(cs) {
 287                 printf(msg425);
 288                 printf("425 Child listener error %s\r\n", strerror(cs));
 289                 close(ftpdata_fd);
 290                 ftpdata_fd = -1;
 291                 return(BAD);
 292         }
 293 #ifdef DEBUG
 294         fprintf(logfile, "ftpd: parent %d  child %d pasv done\n", getpid(), lpid);
 295         fflush(logfile);
 296 #endif
 297         return(GOOD);
 298    }
 299
 300    if(ftpdata_fd >= 0)
 301         return(GOOD);
 302
 303    if((tcp_device = getenv("TCP_DEVICE")) == NULL)
 304         tcp_device = TCP_DEVICE;
 305
 306    if((ftpdata_fd = open(tcp_device, O_RDWR)) < 0) {
 307         printf(msg425);
 308         printf("425 Could not open tcp_device. Error %s\r\n", strerror(errno));
 309         return(BAD);
 310    }
 311
 312    tcpconf.nwtc_flags = NWTC_LP_SET | NWTC_SET_RA | NWTC_SET_RP;
 313    tcpconf.nwtc_remaddr = dataaddr;
 314    tcpconf.nwtc_remport = dataport;
 315    tcpconf.nwtc_locport = htons(20);
 316
 317    s = ioctl(ftpdata_fd, NWIOSTCPCONF, &tcpconf);
 318    if(s < 0) {
 319         printf(msg425);
 320         printf("425 Could not ioctl NWIOSTCPCONF. Error %s\r\n", strerror(errno));
 321         close(ftpdata_fd);
 322         ftpdata_fd = -1;
 323         return(BAD);
 324    }
 325
 326    s = ioctl(ftpdata_fd, NWIOGTCPCONF, &tcpconf);
 327    if(s < 0) {
 328         printf(msg425);
 329         printf("425 Could not ioctl NWIOGTCPCONF. Error %s\r\n", strerror(errno));
 330         close(ftpdata_fd);
 331         ftpdata_fd = -1;
 332         return(BAD);
 333    }
 334
 335    tcpcopt.nwtcl_flags = 0;
 336
 337    retry = 0;
 338    do  {
 339 #ifdef DEBUG
 340         fprintf(logfile, "try connect\n"); fflush(logfile);
 341         fflush(logfile);
 342 #endif
 343         sleep(2);
 344         s = ioctl(ftpdata_fd, NWIOTCPCONN, &tcpcopt);
 345 #ifdef DEBUG
 346         fprintf(logfile, "after connect %d %d\n", s, errno);
 347         fflush(logfile);
 348 #endif
 349         if(!(s == -1 && errno == EAGAIN)) break;
 350         if(retry++ > 10) break;
 351         sleep(1);
 352    } while(1);
 353    if(s < 0) {
 354         printf(msg425);
 355         printf("425 Could not ioctl NWIOTCPCONN. Error %s\r\n", strerror(errno));
 356         close(ftpdata_fd);
 357         ftpdata_fd = -1;
 358         return(BAD);
 359    }
 360
 361    s = ioctl(ftpdata_fd, NWIOGTCPCONF, &tcpconf);
 362    if(s < 0) {
 363         printf(msg425);
 364         printf("425 Could not ioctl NWIOGTCPCONF. Error %s\r\n", strerror(errno));
 365         close(ftpdata_fd);
 366         ftpdata_fd = -1;
 367         return(BAD);
 368    }
 369
 370    return(GOOD);
 371 }
 372
 373 /* Clean up stuff we did to get a Pasv connection going */
 374 int CleanUpPasv()
 375 {
 376 int s, cs;
 377
 378    if(lpid >= 0) {
 379         kill(lpid, SIGKILL);
 380         while(1) {
 381                 s = waitpid(lpid, &cs, 0);
 382                 if(s == lpid || (s == -1 && errno == ECHILD))
 383                         break;
 384         }
 385    }
 386
 387    lpid = -1;
 388
 389    didpassive = 0;
 390
 391    return(GOOD);
 392 }
 393
 394 void GetNetInfo()
 395 {
 396 nwio_tcpconf_t tcpconf;
 397 int s;
 398 struct hostent *hostent;
 399
 400    /* Ask the system what our hostname is. */
 401    if(gethostname(myhostname, sizeof(myhostname)) < 0)
 402         strcpy(myhostname, "unknown");
 403
 404    /* lets get our ip address and the clients ip address */
 405    s = ioctl(0, NWIOGTCPCONF, &tcpconf);
 406    if(s < 0) {
 407         printf("421 FTP service unable to get remote ip address. Closing.\r\n");
 408         fflush(stdout);
 409         exit(1);
 410    }
 411
 412    myipaddr = tcpconf.nwtc_locaddr;
 413    myport = tcpconf.nwtc_locport;
 414    rmtipaddr = tcpconf.nwtc_remaddr;
 415    rmtport = tcpconf.nwtc_remport;
 416
 417    /* Look up the host name of the remote host. */
 418    hostent = gethostbyaddr((char *) &rmtipaddr, sizeof(rmtipaddr), AF_INET);
 419    if(!hostent)
 420         strcpy(rmthostname, inet_ntoa(rmtipaddr));
 421    else {
 422         strncpy(rmthostname, hostent->h_name, sizeof(rmthostname)-1);
 423         rmthostname[sizeof(rmthostname)-1] = '\0';
 424    }
 425 }
 426
 427 static void timeout(sig)
 428 int sig;
 429 {
 430    gottimeout = 1;
 431 }