/* $OpenBSD: ftp.c,v 1.3 2000/05/31 03:09:22 itojun Exp $ */ /* $KAME: ftp.c,v 1.7 2000/05/31 03:06:07 itojun Exp $ */ /* * Copyright (C) 1997 and 1998 WIDE Project. * All rights reserved. * * Redistribution and use in source and binary forms, with or without * modification, are permitted provided that the following conditions * are met: * 1. Redistributions of source code must retain the above copyright * notice, this list of conditions and the following disclaimer. * 2. Redistributions in binary form must reproduce the above copyright * notice, this list of conditions and the following disclaimer in the * documentation and/or other materials provided with the distribution. * 3. Neither the name of the project nor the names of its contributors * may be used to endorse or promote products derived from this software * without specific prior written permission. * * THIS SOFTWARE IS PROVIDED BY THE PROJECT AND CONTRIBUTORS ``AS IS'' AND * ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE * IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE * ARE DISCLAIMED. IN NO EVENT SHALL THE PROJECT OR CONTRIBUTORS BE LIABLE * FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL * DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS * OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) * HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT * LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY * OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF * SUCH DAMAGE. */ #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include #include "faithd.h" static char rbuf[MSS]; static char sbuf[MSS]; static int passivemode = 0; static int wport4 = -1; /* listen() to active */ static int wport6 = -1; /* listen() to passive */ static int port4 = -1; /* active: inbound passive: outbound */ static int port6 = -1; /* active: outbound passive: inbound */ static struct sockaddr_storage data4; /* server data address */ static struct sockaddr_storage data6; /* client data address */ static int epsvall = 0; #ifdef FAITH4 enum state { NONE, LPRT, EPRT, PORT, LPSV, EPSV, PASV }; #else enum state { NONE, LPRT, EPRT, LPSV, EPSV }; #endif static int ftp_activeconn __P((void)); static int ftp_passiveconn __P((void)); static int ftp_copy __P((int, int)); static int ftp_copyresult __P((int, int, enum state)); static int ftp_copycommand __P((int, int, enum state *)); void ftp_relay(int ctl6, int ctl4) { fd_set readfds; int error; enum state state = NONE; struct timeval tv; syslog(LOG_INFO, "starting ftp control connection"); for (;;) { FD_ZERO(&readfds); FD_SET(ctl4, &readfds); FD_SET(ctl6, &readfds); if (0 <= port4) FD_SET(port4, &readfds); if (0 <= port6) FD_SET(port6, &readfds); #if 0 if (0 <= wport4) FD_SET(wport4, &readfds); if (0 <= wport6) FD_SET(wport6, &readfds); #endif tv.tv_sec = FAITH_TIMEOUT; tv.tv_usec = 0; error = select(256, &readfds, NULL, NULL, &tv); if (error == -1) exit_failure("select: %s", ERRSTR); else if (error == 0) exit_failure("connection timeout"); /* * The order of the following checks does (slightly) matter. * It is important to visit all checks (do not use "continue"), * otherwise some of the pipe may become full and we cannot * relay correctly. */ if (FD_ISSET(ctl6, &readfds)) { /* * copy control connection from the client. * command translation is necessary. */ error = ftp_copycommand(ctl6, ctl4, &state); switch (error) { case -1: goto bad; case 0: close(ctl4); close(ctl6); exit_success("terminating ftp control connection"); /*NOTREACHED*/ default: break; } } if (FD_ISSET(ctl4, &readfds)) { /* * copy control connection from the server * translation of result code is necessary. */ error = ftp_copyresult(ctl4, ctl6, state); switch (error) { case -1: goto bad; case 0: close(ctl4); close(ctl6); exit_success("terminating ftp control connection"); /*NOTREACHED*/ default: break; } } if (0 <= port4 && 0 <= port6 && FD_ISSET(port4, &readfds)) { /* * copy data connection. * no special treatment necessary. */ if (FD_ISSET(port4, &readfds)) error = ftp_copy(port4, port6); switch (error) { case -1: goto bad; case 0: close(port4); close(port6); port4 = port6 = -1; syslog(LOG_INFO, "terminating data connection"); break; default: break; } } if (0 <= port4 && 0 <= port6 && FD_ISSET(port6, &readfds)) { /* * copy data connection. * no special treatment necessary. */ if (FD_ISSET(port6, &readfds)) error = ftp_copy(port6, port4); switch (error) { case -1: goto bad; case 0: close(port4); close(port6); port4 = port6 = -1; syslog(LOG_INFO, "terminating data connection"); break; default: break; } } #if 0 if (wport4 && FD_ISSET(wport4, &readfds)) { /* * establish active data connection from the server. */ ftp_activeconn(); } if (wport6 && FD_ISSET(wport6, &readfds)) { /* * establish passive data connection from the client. */ ftp_passiveconn(); } #endif } bad: exit_failure(ERRSTR); } static int ftp_activeconn() { int n; int error; fd_set set; struct timeval timeout; struct sockaddr *sa; /* get active connection from server */ FD_ZERO(&set); FD_SET(wport4, &set); timeout.tv_sec = 120; timeout.tv_usec = -1; n = sizeof(data4); if (select(wport4 + 1, &set, NULL, NULL, &timeout) == 0 || (port4 = accept(wport4, (struct sockaddr *)&data4, &n)) < 0) { close(wport4); wport4 = -1; syslog(LOG_INFO, "active mode data connection failed"); return -1; } /* ask active connection to client */ sa = (struct sockaddr *)&data6; port6 = socket(sa->sa_family, SOCK_STREAM, 0); if (port6 == -1) { close(port4); close(wport4); port4 = wport4 = -1; syslog(LOG_INFO, "active mode data connection failed"); return -1; } error = connect(port6, sa, sa->sa_len); if (port6 == -1) { close(port6); close(port4); close(wport4); port6 = port4 = wport4 = -1; syslog(LOG_INFO, "active mode data connection failed"); return -1; } syslog(LOG_INFO, "active mode data connection established"); return 0; } static int ftp_passiveconn() { int n; int error; fd_set set; struct timeval timeout; struct sockaddr *sa; /* get passive connection from client */ FD_ZERO(&set); FD_SET(wport6, &set); timeout.tv_sec = 120; timeout.tv_usec = 0; n = sizeof(data6); if (select(wport6 + 1, &set, NULL, NULL, &timeout) == 0 || (port6 = accept(wport6, (struct sockaddr *)&data6, &n)) < 0) { close(wport6); wport6 = -1; syslog(LOG_INFO, "passive mode data connection failed"); return -1; } /* ask passive connection to server */ sa = (struct sockaddr *)&data4; port4 = socket(sa->sa_family, SOCK_STREAM, 0); if (port4 == -1) { close(wport6); close(port6); wport6 = port6 = -1; syslog(LOG_INFO, "passive mode data connection failed"); return -1; } error = connect(port4, sa, sa->sa_len); if (port4 == -1) { close(wport6); close(port4); close(port6); wport6 = port4 = port6 = -1; syslog(LOG_INFO, "passive mode data connection failed"); return -1; } syslog(LOG_INFO, "passive mode data connection established"); return 0; } static int ftp_copy(int src, int dst) { int error, atmark; int n; /* OOB data handling */ error = ioctl(src, SIOCATMARK, &atmark); if (error != -1 && atmark == 1) { n = read(src, rbuf, 1); if (n == -1) goto bad; send(dst, rbuf, n, MSG_OOB); #if 0 n = read(src, rbuf, sizeof(rbuf)); if (n == -1) goto bad; write(dst, rbuf, n); return n; #endif } n = read(src, rbuf, sizeof(rbuf)); switch (n) { case -1: case 0: return n; default: write(dst, rbuf, n); return n; } bad: exit_failure(ERRSTR); /*NOTREACHED*/ return 0; /* to make gcc happy */ } static int ftp_copyresult(int src, int dst, enum state state) { int error, atmark; int n; char *param; int code; /* OOB data handling */ error = ioctl(src, SIOCATMARK, &atmark); if (error != -1 && atmark == 1) { n = read(src, rbuf, 1); if (n == -1) goto bad; send(dst, rbuf, n, MSG_OOB); #if 0 n = read(src, rbuf, sizeof(rbuf)); if (n == -1) goto bad; write(dst, rbuf, n); return n; #endif } n = read(src, rbuf, sizeof(rbuf)); if (n <= 0) return n; rbuf[n] = '\0'; /* * parse argument */ { char *p; int i; p = rbuf; for (i = 0; i < 3; i++) { if (!isdigit(*p)) { /* invalid reply */ write(dst, rbuf, n); return n; } p++; } if (!isspace(*p)) { /* invalid reply */ write(dst, rbuf, n); return n; } code = atoi(rbuf); param = p; /* param points to first non-command token, if any */ while (*param && isspace(*param)) param++; if (!*param) param = NULL; } switch (state) { case NONE: if (!passivemode && rbuf[0] == '1') { if (ftp_activeconn() < 0) { n = snprintf(rbuf, sizeof(rbuf), "425 Cannot open data connetion\r\n"); } } write(dst, rbuf, n); return n; case LPRT: case EPRT: /* expecting "200 PORT command successful." */ if (code == 200) { char *p; p = strstr(rbuf, "PORT"); if (p) { p[0] = (state == LPRT) ? 'L' : 'E'; p[1] = 'P'; } } else { close(wport4); wport4 = -1; } write(dst, rbuf, n); return n; #ifdef FAITH4 case PORT: /* expecting "200 EPRT command successful." */ if (code == 200) { char *p; p = strstr(rbuf, "EPRT"); if (p) { p[0] = 'P'; p[1] = 'O'; } } else { close(wport4); wport4 = -1; } write(dst, rbuf, n); return n; #endif case LPSV: case EPSV: /* expecting "227 Entering Passive Mode (x,x,x,x,x,x,x)" */ if (code != 227) { passivefail0: close(wport6); wport6 = -1; write(dst, rbuf, n); return n; } { unsigned int ho[4], po[2]; struct sockaddr_in *sin; struct sockaddr_in6 *sin6; u_short port; char *p; /* * PASV result -> LPSV/EPSV result */ p = param; while (*p && *p != '(') p++; if (!*p) goto passivefail0; /*XXX*/ p++; n = sscanf(p, "%u,%u,%u,%u,%u,%u", &ho[0], &ho[1], &ho[2], &ho[3], &po[0], &po[1]); if (n != 6) goto passivefail0; /*XXX*/ /* keep PORT parameter */ memset(&data4, 0, sizeof(data4)); sin = (struct sockaddr_in *)&data4; sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; sin->sin_addr.s_addr = 0; for (n = 0; n < 4; n++) { sin->sin_addr.s_addr |= htonl((ho[n] & 0xff) << ((3 - n) * 8)); } sin->sin_port = htons(((po[0] & 0xff) << 8) | (po[1] & 0xff)); /* get ready for passive data connection */ memset(&data6, 0, sizeof(data6)); sin6 = (struct sockaddr_in6 *)&data6; sin6->sin6_len = sizeof(*sin6); sin6->sin6_family = AF_INET6; wport6 = socket(sin6->sin6_family, SOCK_STREAM, 0); if (wport6 == -1) { passivefail: n = snprintf(sbuf, sizeof(sbuf), "500 could not translate from PASV\r\n"); write(src, sbuf, n); return n; } #ifdef IPV6_FAITH { int on = 1; error = setsockopt(wport6, IPPROTO_IPV6, IPV6_FAITH, &on, sizeof(on)); if (error == -1) exit_error("setsockopt(IPV6_FAITH): %s", ERRSTR); } #endif error = bind(wport6, (struct sockaddr *)sin6, sin6->sin6_len); if (error == -1) { close(wport6); wport6 = -1; goto passivefail; } error = listen(wport6, 1); if (error == -1) { close(wport6); wport6 = -1; goto passivefail; } /* transmit LPSV or EPSV */ /* * addr from dst, port from wport6 */ n = sizeof(data6); error = getsockname(wport6, (struct sockaddr *)&data6, &n); if (error == -1) { close(wport6); wport6 = -1; goto passivefail; } sin6 = (struct sockaddr_in6 *)&data6; port = sin6->sin6_port; n = sizeof(data6); error = getsockname(dst, (struct sockaddr *)&data6, &n); if (error == -1) { close(wport6); wport6 = -1; goto passivefail; } sin6 = (struct sockaddr_in6 *)&data6; sin6->sin6_port = port; if (state == LPSV) { char *a, *p; a = (char *)&sin6->sin6_addr; p = (char *)&sin6->sin6_port; n = snprintf(sbuf, sizeof(sbuf), "228 Entering Long Passive Mode (%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d)\r\n", 6, 16, UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), UC(a[4]), UC(a[5]), UC(a[6]), UC(a[7]), UC(a[8]), UC(a[9]), UC(a[10]), UC(a[11]), UC(a[12]), UC(a[13]), UC(a[14]), UC(a[15]), 2, UC(p[0]), UC(p[1])); write(dst, sbuf, n); passivemode = 1; return n; } else { n = snprintf(sbuf, sizeof(sbuf), "229 Entering Extended Passive Mode (|||%d|)\r\n", ntohs(sin6->sin6_port)); write(dst, sbuf, n); passivemode = 1; return n; } } #ifdef FAITH4 case PASV: /* expecting "229 Entering Extended Passive Mode (|||x|)" */ if (code != 229) { passivefail1: close(wport6); wport6 = -1; write(dst, rbuf, n); return n; } { u_short port; char *p; struct sockaddr_in *sin; struct sockaddr_in6 *sin6; /* * EPSV result -> PORT result */ p = param; while (*p && *p != '(') p++; if (!*p) goto passivefail1; /*XXX*/ p++; n = sscanf(p, "|||%hu|", &port); if (n != 1) goto passivefail1; /*XXX*/ /* keep EPRT parameter */ n = sizeof(data4); error = getpeername(src, (struct sockaddr *)&data4, &n); if (error == -1) goto passivefail1; /*XXX*/ sin6 = (struct sockaddr_in6 *)&data4; sin6->sin6_port = htons(port); /* get ready for passive data connection */ memset(&data6, 0, sizeof(data6)); sin = (struct sockaddr_in *)&data6; sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; wport6 = socket(sin->sin_family, SOCK_STREAM, 0); if (wport6 == -1) { passivefail2: n = snprintf(sbuf, sizeof(sbuf), "500 could not translate from EPSV\r\n"); write(src, sbuf, n); return n; } #ifdef IP_FAITH { int on = 1; error = setsockopt(wport6, IPPROTO_IP, IP_FAITH, &on, sizeof(on)); if (error == -1) exit_error("setsockopt(IP_FAITH): %s", ERRSTR); } #endif error = bind(wport6, (struct sockaddr *)sin, sin->sin_len); if (error == -1) { close(wport6); wport6 = -1; goto passivefail2; } error = listen(wport6, 1); if (error == -1) { close(wport6); wport6 = -1; goto passivefail2; } /* transmit PORT */ /* * addr from dst, port from wport6 */ n = sizeof(data6); error = getsockname(wport6, (struct sockaddr *)&data6, &n); if (error == -1) { close(wport6); wport6 = -1; goto passivefail2; } sin = (struct sockaddr_in *)&data6; port = sin->sin_port; n = sizeof(data6); error = getsockname(dst, (struct sockaddr *)&data6, &n); if (error == -1) { close(wport6); wport6 = -1; goto passivefail2; } sin = (struct sockaddr_in *)&data6; sin->sin_port = port; { char *a, *p; a = (char *)&sin->sin_addr; p = (char *)&sin->sin_port; n = snprintf(sbuf, sizeof(sbuf), "227 Entering Passive Mode (%d,%d,%d,%d,%d,%d)\r\n", UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1])); write(dst, sbuf, n); passivemode = 1; return n; } } #endif /* FAITH4 */ } bad: exit_failure(ERRSTR); /*NOTREACHED*/ return 0; /* to make gcc happy */ } static int ftp_copycommand(int src, int dst, enum state *state) { int error, atmark; int n; unsigned int af, hal, ho[16], pal, po[2]; char *a, *p; char cmd[5], *param; struct sockaddr_in *sin; struct sockaddr_in6 *sin6; enum state nstate; char ch; /* OOB data handling */ error = ioctl(src, SIOCATMARK, &atmark); if (error != -1 && atmark == 1) { n = read(src, rbuf, 1); if (n == -1) goto bad; send(dst, rbuf, n, MSG_OOB); #if 0 n = read(src, rbuf, sizeof(rbuf)); if (n == -1) goto bad; write(dst, rbuf, n); return n; #endif } n = read(src, rbuf, sizeof(rbuf)); if (n <= 0) return n; rbuf[n] = '\0'; if (n < 4) { write(dst, rbuf, n); return n; } /* * parse argument */ { char *p, *q; int i; p = rbuf; q = cmd; for (i = 0; i < 4; i++) { if (!isalpha(*p)) { /* invalid command */ write(dst, rbuf, n); return n; } *q++ = islower(*p) ? toupper(*p) : *p; p++; } if (!isspace(*p)) { /* invalid command */ write(dst, rbuf, n); return n; } *q = '\0'; param = p; /* param points to first non-command token, if any */ while (*param && isspace(*param)) param++; if (!*param) param = NULL; } *state = NONE; if (strcmp(cmd, "LPRT") == 0 && param) { /* * LPRT -> PORT */ nstate = LPRT; close(wport4); close(wport6); close(port4); close(port6); wport4 = wport6 = port4 = port6 = -1; if (epsvall) { n = snprintf(sbuf, sizeof(sbuf), "501 %s disallowed in EPSV ALL\r\n", cmd); write(src, sbuf, n); return n; } n = sscanf(param, "%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u,%u", &af, &hal, &ho[0], &ho[1], &ho[2], &ho[3], &ho[4], &ho[5], &ho[6], &ho[7], &ho[8], &ho[9], &ho[10], &ho[11], &ho[12], &ho[13], &ho[14], &ho[15], &pal, &po[0], &po[1]); if (n != 21 || af != 6 || hal != 16|| pal != 2) { n = snprintf(sbuf, sizeof(sbuf), "501 illegal parameter to LPRT\r\n"); write(src, sbuf, n); return n; } /* keep LPRT parameter */ memset(&data6, 0, sizeof(data6)); sin6 = (struct sockaddr_in6 *)&data6; sin6->sin6_len = sizeof(*sin6); sin6->sin6_family = AF_INET6; for (n = 0; n < 16; n++) sin6->sin6_addr.s6_addr[n] = ho[n]; sin6->sin6_port = htons(((po[0] & 0xff) << 8) | (po[1] & 0xff)); sendport: /* get ready for active data connection */ n = sizeof(data4); error = getsockname(dst, (struct sockaddr *)&data4, &n); if (error == -1) { lprtfail: n = snprintf(sbuf, sizeof(sbuf), "500 could not translate to PORT\r\n"); write(src, sbuf, n); return n; } if (((struct sockaddr *)&data4)->sa_family != AF_INET) goto lprtfail; sin = (struct sockaddr_in *)&data4; sin->sin_port = 0; wport4 = socket(sin->sin_family, SOCK_STREAM, 0); if (wport4 == -1) goto lprtfail; error = bind(wport4, (struct sockaddr *)sin, sin->sin_len); if (error == -1) { close(wport4); wport4 = -1; goto lprtfail; } error = listen(wport4, 1); if (error == -1) { close(wport4); wport4 = -1; goto lprtfail; } /* transmit PORT */ n = sizeof(data4); error = getsockname(wport4, (struct sockaddr *)&data4, &n); if (error == -1) { close(wport4); wport4 = -1; goto lprtfail; } if (((struct sockaddr *)&data4)->sa_family != AF_INET) { close(wport4); wport4 = -1; goto lprtfail; } sin = (struct sockaddr_in *)&data4; a = (char *)&sin->sin_addr; p = (char *)&sin->sin_port; n = snprintf(sbuf, sizeof(sbuf), "PORT %d,%d,%d,%d,%d,%d\r\n", UC(a[0]), UC(a[1]), UC(a[2]), UC(a[3]), UC(p[0]), UC(p[1])); write(dst, sbuf, n); *state = nstate; passivemode = 0; return n; } else if (strcmp(cmd, "EPRT") == 0 && param) { /* * EPRT -> PORT */ char *afp, *hostp, *portp; struct addrinfo hints, *res; nstate = EPRT; close(wport4); close(wport6); close(port4); close(port6); wport4 = wport6 = port4 = port6 = -1; if (epsvall) { n = snprintf(sbuf, sizeof(sbuf), "501 %s disallowed in EPSV ALL\r\n", cmd); write(src, sbuf, n); return n; } p = param; ch = *p++; /* boundary character */ afp = p; while (*p && *p != ch) p++; if (!*p) { eprtparamfail: n = snprintf(sbuf, sizeof(sbuf), "501 illegal parameter to EPRT\r\n"); write(src, sbuf, n); return n; } *p++ = '\0'; hostp = p; while (*p && *p != ch) p++; if (!*p) goto eprtparamfail; *p++ = '\0'; portp = p; while (*p && *p != ch) p++; if (!*p) goto eprtparamfail; *p++ = '\0'; n = sscanf(afp, "%d", &af); if (n != 1 || af != 2) { n = snprintf(sbuf, sizeof(sbuf), "501 unsupported address family to EPRT\r\n"); write(src, sbuf, n); return n; } memset(&hints, 0, sizeof(hints)); hints.ai_family = AF_UNSPEC; error = getaddrinfo(hostp, portp, &hints, &res); if (error) { n = snprintf(sbuf, sizeof(sbuf), "501 EPRT: %s\r\n", gai_strerror(error)); write(src, sbuf, n); return n; } if (res->ai_next) { n = snprintf(sbuf, sizeof(sbuf), "501 EPRT: %s resolved to multiple addresses\r\n", hostp); write(src, sbuf, n); return n; } memcpy(&data6, res->ai_addr, res->ai_addrlen); goto sendport; } else if (strcmp(cmd, "LPSV") == 0 && !param) { /* * LPSV -> PASV */ nstate = LPSV; close(wport4); close(wport6); close(port4); close(port6); wport4 = wport6 = port4 = port6 = -1; if (epsvall) { n = snprintf(sbuf, sizeof(sbuf), "501 %s disallowed in EPSV ALL\r\n", cmd); write(src, sbuf, n); return n; } /* transmit PASV */ n = snprintf(sbuf, sizeof(sbuf), "PASV\r\n"); write(dst, sbuf, n); *state = LPSV; passivemode = 0; /* to be set to 1 later */ return n; } else if (strcmp(cmd, "EPSV") == 0 && !param) { /* * EPSV -> PASV */ close(wport4); close(wport6); close(port4); close(port6); wport4 = wport6 = port4 = port6 = -1; n = snprintf(sbuf, sizeof(sbuf), "PASV\r\n"); write(dst, sbuf, n); *state = EPSV; passivemode = 0; /* to be set to 1 later */ return n; } else if (strcmp(cmd, "EPSV") == 0 && param && strncasecmp(param, "ALL", 3) == 0 && isspace(param[3])) { /* * EPSV ALL */ epsvall = 1; n = snprintf(sbuf, sizeof(sbuf), "200 EPSV ALL command successful.\r\n"); write(src, sbuf, n); return n; #ifdef FAITH4 } else if (strcmp(cmd, "PORT") == 0 && param) { /* * PORT -> EPRT */ char host[NI_MAXHOST], serv[NI_MAXSERV]; nstate = PORT; close(wport4); close(wport6); close(port4); close(port6); wport4 = wport6 = port4 = port6 = -1; p = param; n = sscanf(p, "%u,%u,%u,%u,%u,%u", &ho[0], &ho[1], &ho[2], &ho[3], &po[0], &po[1]); if (n != 6) { n = snprintf(sbuf, sizeof(sbuf), "501 illegal parameter to PORT\r\n"); write(src, sbuf, n); return n; } memset(&data6, 0, sizeof(data6)); sin = (struct sockaddr_in *)&data6; sin->sin_len = sizeof(*sin); sin->sin_family = AF_INET; sin->sin_addr.s_addr = htonl( ((ho[0] & 0xff) << 24) | ((ho[1] & 0xff) << 16) | ((ho[2] & 0xff) << 8) | (ho[3] & 0xff)); sin->sin_port = htons(((po[0] & 0xff) << 8) | (po[1] & 0xff)); /* get ready for active data connection */ n = sizeof(data4); error = getsockname(dst, (struct sockaddr *)&data4, &n); if (error == -1) { portfail: n = snprintf(sbuf, sizeof(sbuf), "500 could not translate to EPRT\r\n"); write(src, sbuf, n); return n; } if (((struct sockaddr *)&data4)->sa_family != AF_INET6) goto portfail; ((struct sockaddr_in6 *)&data4)->sin6_port = 0; sa = (struct sockaddr *)&data4; wport4 = socket(sa->sa_family, SOCK_STREAM, 0); if (wport4 == -1) goto portfail; error = bind(wport4, sa, sa->sa_len); if (error == -1) { close(wport4); wport4 = -1; goto portfail; } error = listen(wport4, 1); if (error == -1) { close(wport4); wport4 = -1; goto portfail; } /* transmit EPRT */ n = sizeof(data4); error = getsockname(wport4, (struct sockaddr *)&data4, &n); if (error == -1) { close(wport4); wport4 = -1; goto portfail; } af = 2; sa = (struct sockaddr *)&data4; if (getnameinfo(sa, sa->sa_len, host, sizeof(host), serv, sizeof(serv), NI_NUMERICHOST | NI_NUMERICSERV)) { close(wport4); wport4 = -1; goto portfail; } n = snprintf(sbuf, sizeof(sbuf), "EPRT |%d|%s|%s|\r\n", af, host, serv); write(dst, sbuf, n); *state = nstate; passivemode = 0; return n; } else if (strcmp(cmd, "PASV") == 0 && !param) { /* * PASV -> EPSV */ nstate = PASV; close(wport4); close(wport6); close(port4); close(port6); wport4 = wport6 = port4 = port6 = -1; /* transmit EPSV */ n = snprintf(sbuf, sizeof(sbuf), "EPSV\r\n"); write(dst, sbuf, n); *state = PASV; passivemode = 0; /* to be set to 1 later */ return n; #else /* FAITH4 */ } else if (strcmp(cmd, "PORT") == 0 || strcmp(cmd, "PASV") == 0) { /* * reject PORT/PASV */ n = snprintf(sbuf, sizeof(sbuf), "502 %s not implemented.\r\n", cmd); write(src, sbuf, n); return n; #endif /* FAITH4 */ } else if (passivemode && (strcmp(cmd, "STOR") == 0 || strcmp(cmd, "STOU") == 0 || strcmp(cmd, "RETR") == 0 || strcmp(cmd, "LIST") == 0 || strcmp(cmd, "NLST") == 0 || strcmp(cmd, "APPE") == 0)) { /* * commands with data transfer. need to care about passive * mode data connection. */ if (ftp_passiveconn() < 0) { n = snprintf(sbuf, sizeof(sbuf), "425 Cannot open data connetion\r\n"); write(src, sbuf, n); } else { /* simply relay the command */ write(dst, rbuf, n); } *state = NONE; return n; } else { /* simply relay it */ *state = NONE; write(dst, rbuf, n); return n; } bad: exit_failure(ERRSTR); /*NOTREACHED*/ return 0; /* to make gcc happy */ }