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Diffstat (limited to 'src/ftp-basic.c')
| -rw-r--r-- | src/ftp-basic.c | 1342 |
1 files changed, 1342 insertions, 0 deletions
diff --git a/src/ftp-basic.c b/src/ftp-basic.c new file mode 100644 index 0000000..197cd83 --- /dev/null +++ b/src/ftp-basic.c @@ -0,0 +1,1342 @@ +/* Basic FTP routines. + Copyright (C) 1996-2011, 2014-2015, 2018-2020 Free Software + Foundation, Inc. + +This file is part of GNU Wget. + +GNU Wget is free software; you can redistribute it and/or modify +it under the terms of the GNU General Public License as published by +the Free Software Foundation; either version 3 of the License, or + (at your option) any later version. + +GNU Wget is distributed in the hope that it will be useful, +but WITHOUT ANY WARRANTY; without even the implied warranty of +MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the +GNU General Public License for more details. + +You should have received a copy of the GNU General Public License +along with Wget. If not, see <http://www.gnu.org/licenses/>. + +Additional permission under GNU GPL version 3 section 7 + +If you modify this program, or any covered work, by linking or +combining it with the OpenSSL project's OpenSSL library (or a +modified version of that library), containing parts covered by the +terms of the OpenSSL or SSLeay licenses, the Free Software Foundation +grants you additional permission to convey the resulting work. +Corresponding Source for a non-source form of such a combination +shall include the source code for the parts of OpenSSL used as well +as that of the covered work. */ + +#include "wget.h" + +#include <assert.h> +#include <stdio.h> +#include <stdlib.h> +#include <errno.h> + +#include <string.h> +#include <unistd.h> +#include "utils.h" +#include "connect.h" +#include "host.h" +#include "ftp.h" +#include "retr.h" +#include "c-strcase.h" + + +/* Get the response of FTP server and allocate enough room to handle + it. <CR> and <LF> characters are stripped from the line, and the + line is 0-terminated. All the response lines but the last one are + skipped. The last line is determined as described in RFC959. + + If the line is successfully read, FTPOK is returned, and *ret_line + is assigned a freshly allocated line. Otherwise, FTPRERR is + returned, and the value of *ret_line should be ignored. */ + +uerr_t +ftp_response (int fd, char **ret_line) +{ + for (;;) + { + char *p; + char *line = fd_read_line (fd); + if (!line) + return FTPRERR; + + /* Strip trailing CRLF before printing the line, so that + quoting doesn't include bogus \012 and \015. */ + if ((p = strpbrk(line , "\r\n"))) + *p = 0; + + if (opt.server_response) + logprintf (LOG_NOTQUIET, "%s\n", + quotearg_style (escape_quoting_style, line)); + else + DEBUGP (("%s\n", quotearg_style (escape_quoting_style, line))); + + /* The last line of output is the one that begins with "ddd ". */ + if (c_isdigit (line[0]) && c_isdigit (line[1]) && c_isdigit (line[2]) + && line[3] == ' ') + { + *ret_line = line; + return FTPOK; + } + xfree (line); + } +} + +/* Returns the malloc-ed FTP request, ending with <CR><LF>, printing + it if printing is required. If VALUE is NULL, just use + command<CR><LF>. */ +static char * +ftp_request (const char *command, const char *value) +{ + char *res; + + if (value) + { + char *defanged = NULL, buf[256]; + + /* Check for newlines in VALUE (possibly injected by the %0A URL + escape) making the callers inadvertently send multiple FTP + commands at once. Without this check an attacker could + intentionally redirect to ftp://server/fakedir%0Acommand.../ + and execute arbitrary FTP command on a remote FTP server. */ + if (strpbrk (value, "\r\n")) + { + /* Copy VALUE to the stack and modify CR/LF to space. */ + char *p; + size_t len = strlen(value); + + if (len < sizeof (buf)) + defanged = buf; + else + defanged = xmalloc (len + 1); + + memcpy (defanged, value, len + 1); + + for (p = defanged; *p; p++) + if (*p == '\r' || *p == '\n') + *p = ' '; + + DEBUGP (("\nDetected newlines in %s \"%s\"; changing to %s \"%s\"\n", + command, quotearg_style (escape_quoting_style, value), + command, quotearg_style (escape_quoting_style, defanged))); + + /* Make VALUE point to the defanged copy of the string. */ + value = defanged; + } + res = concat_strings (command, " ", value, "\r\n", (char *) 0); + + if (defanged != buf) + xfree (defanged); + } + else + res = concat_strings (command, "\r\n", (char *) 0); + if (opt.server_response) + { + /* Hack: don't print out password. */ + if (strncmp (res, "PASS", 4) != 0) + logprintf (LOG_ALWAYS, "--> %s\n", res); + else + logputs (LOG_ALWAYS, "--> PASS Turtle Power!\n\n"); + } + else + DEBUGP (("\n--> %s\n", res)); + return res; +} + +uerr_t +ftp_greeting (int csock) +{ + uerr_t err = FTPOK; + char *response = NULL; + + err = ftp_response (csock, &response); + if (err != FTPOK) + goto bail; + if (*response != '2') + err = FTPSRVERR; + +bail: + if (response) + xfree (response); + return err; +} +/* Sends the USER and PASS commands to the server, to control + connection socket csock. */ +uerr_t +ftp_login (int csock, const char *acc, const char *pass) +{ + uerr_t err; + char *request, *respline; + int nwritten; + + /* Send USER username. */ + request = ftp_request ("USER", acc); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + /* An unprobable possibility of logging without a password. */ + if (*respline == '2') + { + xfree (respline); + return FTPOK; + } + /* Else, only response 3 is appropriate. */ + if (*respline != '3') + { + xfree (respline); + return FTPLOGREFUSED; + } +#ifdef ENABLE_OPIE + { + static const char *skey_head[] = { + "331 s/key ", + "331 opiekey " + }; + size_t i; + const char *seed = NULL; + + for (i = 0; i < countof (skey_head); i++) + { + int l = strlen (skey_head[i]); + if (0 == c_strncasecmp (skey_head[i], respline, l)) + { + seed = respline + l; + break; + } + } + if (seed) + { + int skey_sequence = 0; + + /* Extract the sequence from SEED. */ + for (; c_isdigit (*seed); seed++) + skey_sequence = 10 * skey_sequence + *seed - '0'; + if (*seed == ' ') + ++seed; + else + { + xfree (respline); + return FTPLOGREFUSED; + } + /* Replace the password with the SKEY response to the + challenge. */ + pass = skey_response (skey_sequence, seed, pass); + } + } +#endif /* ENABLE_OPIE */ + xfree (respline); + /* Send PASS password. */ + request = ftp_request ("PASS", pass); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline != '2') + { + xfree (respline); + return FTPLOGINC; + } + xfree (respline); + /* All OK. */ + return FTPOK; +} + +static void +ip_address_to_port_repr (const ip_address *addr, int port, char *buf, + size_t buflen) +{ + unsigned char *ptr; + + assert (addr->family == AF_INET); + /* buf must contain the argument of PORT (of the form a,b,c,d,e,f). */ + assert (buflen >= 6 * 4); + + ptr = IP_INADDR_DATA (addr); + snprintf (buf, buflen, "%d,%d,%d,%d,%d,%d", ptr[0], ptr[1], + ptr[2], ptr[3], (port & 0xff00) >> 8, port & 0xff); + buf[buflen - 1] = '\0'; +} + +/* Bind a port and send the appropriate PORT command to the FTP + server. Use acceptport after RETR, to get the socket of data + connection. */ +uerr_t +ftp_port (int csock, int *local_sock) +{ + uerr_t err; + char *request, *respline; + ip_address addr; + int nwritten; + int port; + /* Must contain the argument of PORT (of the form a,b,c,d,e,f). */ + char bytes[6 * 4 + 1]; + + /* Get the address of this side of the connection. */ + if (!socket_ip_address (csock, &addr, ENDPOINT_LOCAL)) + return FTPSYSERR; + + assert (addr.family == AF_INET); + + /* Setting port to 0 lets the system choose a free port. */ + port = 0; + + /* Bind the port. */ + *local_sock = bind_local (&addr, &port); + if (*local_sock < 0) + return FTPSYSERR; + + /* Construct the argument of PORT (of the form a,b,c,d,e,f). */ + ip_address_to_port_repr (&addr, port, bytes, sizeof (bytes)); + + /* Send PORT request. */ + request = ftp_request ("PORT", bytes); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + fd_close (*local_sock); + return WRITEFAILED; + } + xfree (request); + + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + { + fd_close (*local_sock); + return err; + } + if (*respline != '2') + { + xfree (respline); + fd_close (*local_sock); + return FTPPORTERR; + } + xfree (respline); + return FTPOK; +} + +#ifdef ENABLE_IPV6 +static void +ip_address_to_lprt_repr (const ip_address *addr, int port, char *buf, + size_t buflen) +{ + unsigned char *ptr = IP_INADDR_DATA (addr); + + /* buf must contain the argument of LPRT (of the form af,n,h1,h2,...,hn,p1,p2). */ + assert (buflen >= 21 * 4); + + /* Construct the argument of LPRT (of the form af,n,h1,h2,...,hn,p1,p2). */ + switch (addr->family) + { + case AF_INET: + snprintf (buf, buflen, "%d,%d,%d,%d,%d,%d,%d,%d,%d", 4, 4, + ptr[0], ptr[1], ptr[2], ptr[3], 2, + (port & 0xff00) >> 8, port & 0xff); + break; + case AF_INET6: + snprintf (buf, buflen, + "%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d,%d", + 6, 16, + ptr[0], ptr[1], ptr[2], ptr[3], ptr[4], ptr[5], ptr[6], ptr[7], + ptr[8], ptr[9], ptr[10], ptr[11], ptr[12], ptr[13], ptr[14], ptr[15], + 2, (port & 0xff00) >> 8, port & 0xff); + break; + default: + abort (); + } +} + +/* Bind a port and send the appropriate PORT command to the FTP + server. Use acceptport after RETR, to get the socket of data + connection. */ +uerr_t +ftp_lprt (int csock, int *local_sock) +{ + uerr_t err; + char *request, *respline; + ip_address addr; + int nwritten; + int port; + /* Must contain the argument of LPRT (of the form af,n,h1,h2,...,hn,p1,p2). */ + char bytes[21 * 4 + 1]; + + /* Get the address of this side of the connection. */ + if (!socket_ip_address (csock, &addr, ENDPOINT_LOCAL)) + return FTPSYSERR; + + assert (addr.family == AF_INET || addr.family == AF_INET6); + + /* Setting port to 0 lets the system choose a free port. */ + port = 0; + + /* Bind the port. */ + *local_sock = bind_local (&addr, &port); + if (*local_sock < 0) + return FTPSYSERR; + + /* Construct the argument of LPRT (of the form af,n,h1,h2,...,hn,p1,p2). */ + ip_address_to_lprt_repr (&addr, port, bytes, sizeof (bytes)); + + /* Send PORT request. */ + request = ftp_request ("LPRT", bytes); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + fd_close (*local_sock); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + { + fd_close (*local_sock); + return err; + } + if (*respline != '2') + { + xfree (respline); + fd_close (*local_sock); + return FTPPORTERR; + } + xfree (respline); + return FTPOK; +} + +static void +ip_address_to_eprt_repr (const ip_address *addr, int port, char *buf, + size_t buflen) +{ + int afnum; + + /* buf must contain the argument of EPRT (of the form |af|addr|port|). + * 4 chars for the | separators, INET6_ADDRSTRLEN chars for addr + * 1 char for af (1-2) and 5 chars for port (0-65535) */ + assert (buflen >= 4 + INET6_ADDRSTRLEN + 1 + 5); + + /* Construct the argument of EPRT (of the form |af|addr|port|). */ + afnum = (addr->family == AF_INET ? 1 : 2); + snprintf (buf, buflen, "|%d|%s|%d|", afnum, print_address (addr), port); + buf[buflen - 1] = '\0'; +} + +/* Bind a port and send the appropriate PORT command to the FTP + server. Use acceptport after RETR, to get the socket of data + connection. */ +uerr_t +ftp_eprt (int csock, int *local_sock) +{ + uerr_t err; + char *request, *respline; + ip_address addr; + int nwritten; + int port; + /* Must contain the argument of EPRT (of the form |af|addr|port|). + * 4 chars for the | separators, INET6_ADDRSTRLEN chars for addr + * 1 char for af (1-2) and 5 chars for port (0-65535) */ + char bytes[4 + INET6_ADDRSTRLEN + 1 + 5 + 1]; + + /* Get the address of this side of the connection. */ + if (!socket_ip_address (csock, &addr, ENDPOINT_LOCAL)) + return FTPSYSERR; + + /* Setting port to 0 lets the system choose a free port. */ + port = 0; + + /* Bind the port. */ + *local_sock = bind_local (&addr, &port); + if (*local_sock < 0) + return FTPSYSERR; + + /* Construct the argument of EPRT (of the form |af|addr|port|). */ + ip_address_to_eprt_repr (&addr, port, bytes, sizeof (bytes)); + + /* Send PORT request. */ + request = ftp_request ("EPRT", bytes); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + fd_close (*local_sock); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + { + fd_close (*local_sock); + return err; + } + if (*respline != '2') + { + xfree (respline); + fd_close (*local_sock); + return FTPPORTERR; + } + xfree (respline); + return FTPOK; +} +#endif + +#ifdef HAVE_SSL +/* + * The following three functions defined into this #ifdef block + * wrap the extended FTP commands defined in RFC 2228 (FTP Security Extensions). + * Currently, only FTPS is supported, so these functions are only compiled when SSL + * support is available, because there's no point in using FTPS when there's no SSL. + * Shall someone add new secure FTP protocols in the future, feel free to remove this + * #ifdef, or add new constants to it. + */ + +/* + * Sends an AUTH command as defined by RFC 2228, + * deriving its argument from the scheme. For example, if the provided scheme + * is SCHEME_FTPS, the command sent will be "AUTH TLS". Currently, this is the only + * scheme supported, so this function will return FTPNOAUTH when supplied a different + * one. It will also return FTPNOAUTH if the target server does not support FTPS. + */ +uerr_t +ftp_auth (int csock, enum url_scheme scheme) +{ + uerr_t err = 0; + int written = 0; + char *request = NULL, *response = NULL; + + if (scheme == SCHEME_FTPS) + { + request = ftp_request ("AUTH", "TLS"); + written = fd_write (csock, request, strlen (request), -1); + if (written < 0) + { + err = WRITEFAILED; + goto bail; + } + err = ftp_response (csock, &response); + if (err != FTPOK) + goto bail; + if (*response != '2') + err = FTPNOAUTH; + } + else + err = FTPNOAUTH; + +bail: + xfree (request); + xfree (response); + + return err; +} + +uerr_t +ftp_pbsz (int csock, int pbsz) +{ + uerr_t err = 0; + int written = 0; + char spbsz[5]; + char *request = NULL, *response = NULL; + + snprintf (spbsz, 5, "%d", pbsz); + request = ftp_request ("PBSZ", spbsz); + written = fd_write (csock, request, strlen (request), -1); + if (written < 0) + { + err = WRITEFAILED; + goto bail; + } + + err = ftp_response (csock, &response); + if (err != FTPOK) + goto bail; + if (*response != '2') + err = FTPNOPBSZ; + +bail: + xfree (request); + xfree (response); + + return err; +} + +uerr_t +ftp_prot (int csock, enum prot_level prot) +{ + uerr_t err = 0; + int written = 0; + char *request = NULL, *response = NULL; + /* value must be a single character value */ + char value[2]; + + value[0] = prot; + value[1] = '\0'; + + request = ftp_request ("PROT", value); + written = fd_write (csock, request, strlen (request), -1); + if (written < 0) + { + err = WRITEFAILED; + goto bail; + } + + err = ftp_response (csock, &response); + if (err != FTPOK) + goto bail; + if (*response != '2') + err = FTPNOPROT; + +bail: + xfree (request); + xfree (response); + + return err; +} +#endif /* HAVE_SSL */ + +/* Similar to ftp_port, but uses `PASV' to initiate the passive FTP + transfer. Reads the response from server and parses it. Reads the + host and port addresses and returns them. */ +uerr_t +ftp_pasv (int csock, ip_address *addr, int *port) +{ + char *request, *respline, *s; + int nwritten, i; + uerr_t err; + unsigned char tmp[6]; + + assert (addr != NULL); + assert (port != NULL); + + xzero (*addr); + + /* Form the request. */ + request = ftp_request ("PASV", NULL); + /* And send it. */ + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get the server response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline != '2') + { + xfree (respline); + return FTPNOPASV; + } + /* Parse the request. */ + s = respline; + for (s += 4; *s && !c_isdigit (*s); s++) + ; + if (!*s) + { + xfree (respline); + return FTPINVPASV; + } + for (i = 0; i < 6; i++) + { + tmp[i] = 0; + for (; c_isdigit (*s); s++) + tmp[i] = (*s - '0') + 10 * tmp[i]; + if (*s == ',') + s++; + else if (i < 5) + { + /* When on the last number, anything can be a terminator. */ + xfree (respline); + return FTPINVPASV; + } + } + xfree (respline); + + addr->family = AF_INET; + memcpy (IP_INADDR_DATA (addr), tmp, 4); + *port = ((tmp[4] << 8) & 0xff00) + tmp[5]; + + return FTPOK; +} + +#ifdef ENABLE_IPV6 +/* Similar to ftp_lprt, but uses `LPSV' to initiate the passive FTP + transfer. Reads the response from server and parses it. Reads the + host and port addresses and returns them. */ +uerr_t +ftp_lpsv (int csock, ip_address *addr, int *port) +{ + char *request, *respline, *s; + int nwritten, i, af, addrlen, portlen; + uerr_t err; + unsigned char tmp[16]; + unsigned char tmpprt[2]; + + assert (addr != NULL); + assert (port != NULL); + + xzero (*addr); + + /* Form the request. */ + request = ftp_request ("LPSV", NULL); + + /* And send it. */ + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + + /* Get the server response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline != '2') + { + xfree (respline); + return FTPNOPASV; + } + + /* Parse the response. */ + s = respline; + for (s += 4; *s && !c_isdigit (*s); s++) + ; + if (!*s) + { + xfree (respline); + return FTPINVPASV; + } + + /* First, get the address family */ + af = 0; + for (; c_isdigit (*s); s++) + af = (*s - '0') + 10 * af; + + if (af != 4 && af != 6) + { + xfree (respline); + return FTPINVPASV; + } + + if (!*s || *s++ != ',') + { + xfree (respline); + return FTPINVPASV; + } + + /* Then, get the address length */ + addrlen = 0; + for (; c_isdigit (*s); s++) + addrlen = (*s - '0') + 10 * addrlen; + + if (!*s || *s++ != ',') + { + xfree (respline); + return FTPINVPASV; + } + + if (addrlen > 16) + { + xfree (respline); + return FTPINVPASV; + } + + if ((af == 4 && addrlen != 4) + || (af == 6 && addrlen != 16)) + { + xfree (respline); + return FTPINVPASV; + } + + /* Now, we get the actual address */ + for (i = 0; i < addrlen; i++) + { + tmp[i] = 0; + for (; c_isdigit (*s); s++) + tmp[i] = (*s - '0') + 10 * tmp[i]; + if (*s == ',') + s++; + else + { + xfree (respline); + return FTPINVPASV; + } + } + + /* Now, get the port length */ + portlen = 0; + for (; c_isdigit (*s); s++) + portlen = (*s - '0') + 10 * portlen; + + if (!*s || *s++ != ',') + { + xfree (respline); + return FTPINVPASV; + } + + if (portlen > 2) + { + xfree (respline); + return FTPINVPASV; + } + + /* Finally, we get the port number */ + tmpprt[0] = 0; + for (; c_isdigit (*s); s++) + tmpprt[0] = (*s - '0') + 10 * tmpprt[0]; + + if (!*s || *s++ != ',') + { + xfree (respline); + return FTPINVPASV; + } + + tmpprt[1] = 0; + for (; c_isdigit (*s); s++) + tmpprt[1] = (*s - '0') + 10 * tmpprt[1]; + + assert (s != NULL); + + if (af == 4) + { + addr->family = AF_INET; + memcpy (IP_INADDR_DATA (addr), tmp, 4); + *port = ((tmpprt[0] << 8) & 0xff00) + tmpprt[1]; + DEBUGP (("lpsv addr is: %s\n", print_address(addr))); + DEBUGP (("tmpprt[0] is: %d\n", tmpprt[0])); + DEBUGP (("tmpprt[1] is: %d\n", tmpprt[1])); + DEBUGP (("*port is: %d\n", *port)); + } + else + { + assert (af == 6); + addr->family = AF_INET6; + memcpy (IP_INADDR_DATA (addr), tmp, 16); + *port = ((tmpprt[0] << 8) & 0xff00) + tmpprt[1]; + DEBUGP (("lpsv addr is: %s\n", print_address(addr))); + DEBUGP (("tmpprt[0] is: %d\n", tmpprt[0])); + DEBUGP (("tmpprt[1] is: %d\n", tmpprt[1])); + DEBUGP (("*port is: %d\n", *port)); + } + + xfree (respline); + return FTPOK; +} + +/* Similar to ftp_eprt, but uses `EPSV' to initiate the passive FTP + transfer. Reads the response from server and parses it. Reads the + host and port addresses and returns them. */ +uerr_t +ftp_epsv (int csock, ip_address *ip, int *port) +{ + char *request, *respline, *start, delim, *s; + int nwritten, i; + uerr_t err; + int tport; + + assert (ip != NULL); + assert (port != NULL); + + /* IP already contains the IP address of the control connection's + peer, so we don't need to call socket_ip_address here. */ + + /* Form the request. */ + /* EPSV 1 means that we ask for IPv4 and EPSV 2 means that we ask for IPv6. */ + request = ftp_request ("EPSV", (ip->family == AF_INET ? "1" : "2")); + + /* And send it. */ + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + + /* Get the server response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline != '2') + { + xfree (respline); + return FTPNOPASV; + } + + assert (respline != NULL); + + DEBUGP(("respline is %s\n", respline)); + + /* Skip the useless stuff and get what's inside the parentheses */ + start = strchr (respline, '('); + if (start == NULL) + { + xfree (respline); + return FTPINVPASV; + } + + /* Skip the first two void fields */ + s = start + 1; + delim = *s++; + if (delim < 33 || delim > 126) + { + xfree (respline); + return FTPINVPASV; + } + + for (i = 0; i < 2; i++) + { + if (*s++ != delim) + { + xfree (respline); + return FTPINVPASV; + } + } + + /* Finally, get the port number */ + for (tport = 0, i = 0; i < 5 && c_isdigit (*s); i++, s++) + tport = (*s - '0') + 10 * tport; + + /* Make sure that the response terminates correctly */ + if (*s++ != delim) + { + xfree (respline); + return FTPINVPASV; + } + + if (*s != ')') + { + xfree (respline); + return FTPINVPASV; + } + + *port = tport; + + xfree (respline); + return FTPOK; +} +#endif + +/* Sends the TYPE request to the server. */ +uerr_t +ftp_type (int csock, int type) +{ + char *request, *respline; + int nwritten; + uerr_t err; + char stype[2]; + + /* Construct argument. */ + stype[0] = type; + stype[1] = 0; + /* Send TYPE request. */ + request = ftp_request ("TYPE", stype); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline != '2') + { + xfree (respline); + return FTPUNKNOWNTYPE; + } + xfree (respline); + /* All OK. */ + return FTPOK; +} + +/* Changes the working directory by issuing a CWD command to the + server. */ +uerr_t +ftp_cwd (int csock, const char *dir) +{ + char *request, *respline; + int nwritten; + uerr_t err; + + /* Send CWD request. */ + request = ftp_request ("CWD", dir); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline == '5') + { + xfree (respline); + return FTPNSFOD; + } + if (*respline != '2') + { + xfree (respline); + return FTPRERR; + } + xfree (respline); + /* All OK. */ + return FTPOK; +} + +/* Sends REST command to the FTP server. */ +uerr_t +ftp_rest (int csock, wgint offset) +{ + char *request, *respline; + int nwritten; + uerr_t err; + + request = ftp_request ("REST", number_to_static_string (offset)); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline != '3') + { + xfree (respline); + return FTPRESTFAIL; + } + xfree (respline); + /* All OK. */ + return FTPOK; +} + +/* Sends RETR command to the FTP server. */ +uerr_t +ftp_retr (int csock, const char *file) +{ + char *request, *respline; + int nwritten; + uerr_t err; + + /* Send RETR request. */ + request = ftp_request ("RETR", file); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline == '5') + { + xfree (respline); + return FTPNSFOD; + } + if (*respline != '1') + { + xfree (respline); + return FTPRERR; + } + xfree (respline); + /* All OK. */ + return FTPOK; +} + +/* Sends the LIST command to the server. If FILE is NULL, send just + `LIST' (no space). */ +uerr_t +ftp_list (int csock, const char *file, bool avoid_list_a, bool avoid_list, + bool *list_a_used) +{ + char *request, *respline; + int nwritten; + uerr_t err; + bool ok = false; + size_t i = 0; + + /* 2013-10-12 Andrea Urbani (matfanjol) + For more information about LIST and "LIST -a" please look at ftp.c, + function getftp, text "__LIST_A_EXPLANATION__". + + If somebody changes the following commands, please, checks also the + later "i" variable. */ + static const char *list_commands[] = { + "LIST -a", + "LIST" + }; + + *list_a_used = false; + + if (avoid_list_a) + { + i = countof (list_commands)- 1; + DEBUGP (("(skipping \"LIST -a\")")); + } + + + do { + /* Send request. */ + request = ftp_request (list_commands[i], file); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err == FTPOK) + { + if (*respline == '5') + { + err = FTPNSFOD; + } + else if (*respline == '1') + { + err = FTPOK; + ok = true; + /* Which list command was used? */ + *list_a_used = (i == 0); + } + else + { + err = FTPRERR; + } + xfree (respline); + } + ++i; + if ((avoid_list) && (i == 1)) + { + /* I skip LIST */ + ++i; + DEBUGP (("(skipping \"LIST\")")); + } + } while (i < countof (list_commands) && !ok); + + return err; +} + +/* Sends the SYST command to the server. */ +uerr_t +ftp_syst (int csock, enum stype *server_type, enum ustype *unix_type) +{ + char *request, *respline; + int nwritten; + uerr_t err; + char *ftp_last_respline; + + /* Send SYST request. */ + request = ftp_request ("SYST", NULL); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline == '5') + { + xfree (respline); + return FTPSRVERR; + } + + ftp_last_respline = strdup (respline); + + /* Skip the number (215, but 200 (!!!) in case of VMS) */ + strtok (respline, " "); + + /* Which system type has been reported (we are interested just in the + first word of the server response)? */ + request = strtok (NULL, " "); + + *unix_type = UST_OTHER; + + if (request == NULL) + *server_type = ST_OTHER; + else if (!c_strcasecmp (request, "VMS")) + *server_type = ST_VMS; + else if (!c_strcasecmp (request, "UNIX")) + { + *server_type = ST_UNIX; + /* 2013-10-17 Andrea Urbani (matfanjol) + I check more in depth the system type */ + if (!c_strncasecmp (ftp_last_respline, "215 UNIX Type: L8", 17)) + *unix_type = UST_TYPE_L8; + else if (!c_strncasecmp (ftp_last_respline, + "215 UNIX MultiNet Unix Emulation V5.3(93)", 41)) + *unix_type = UST_MULTINET; + } + else if (!c_strcasecmp (request, "WINDOWS_NT") + || !c_strcasecmp (request, "WINDOWS2000")) + *server_type = ST_WINNT; + else if (!c_strcasecmp (request, "MACOS")) + *server_type = ST_MACOS; + else if (!c_strcasecmp (request, "OS/400")) + *server_type = ST_OS400; + else + *server_type = ST_OTHER; + + xfree (ftp_last_respline); + xfree (respline); + /* All OK. */ + return FTPOK; +} + +/* Sends the PWD command to the server. */ +uerr_t +ftp_pwd (int csock, char **pwd) +{ + char *request, *respline; + int nwritten; + uerr_t err; + + /* Send PWD request. */ + request = ftp_request ("PWD", NULL); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + return err; + if (*respline == '5') + { + err: + xfree (respline); + return FTPSRVERR; + } + + /* Skip the number (257), leading citation mark, trailing citation mark + and everything following it. */ + strtok (respline, "\""); + request = strtok (NULL, "\""); + if (!request) + /* Treat the malformed response as an error, which the caller has + to handle gracefully anyway. */ + goto err; + + /* Has the `pwd' been already allocated? Free! */ + xfree (*pwd); + + *pwd = xstrdup (request); + + xfree (respline); + /* All OK. */ + return FTPOK; +} + +/* Sends the SIZE command to the server, and returns the value in 'size'. + * If an error occurs, size is set to zero. */ +uerr_t +ftp_size (int csock, const char *file, wgint *size) +{ + char *request, *respline; + int nwritten; + uerr_t err; + + /* Send PWD request. */ + request = ftp_request ("SIZE", file); + nwritten = fd_write (csock, request, strlen (request), -1); + if (nwritten < 0) + { + xfree (request); + *size = 0; + return WRITEFAILED; + } + xfree (request); + /* Get appropriate response. */ + err = ftp_response (csock, &respline); + if (err != FTPOK) + { + *size = 0; + return err; + } + if (*respline == '5') + { + /* + * Probably means SIZE isn't supported on this server. + * Error is nonfatal since SIZE isn't in RFC 959 + */ + xfree (respline); + *size = 0; + return FTPOK; + } + + errno = 0; + *size = str_to_wgint (respline + 4, NULL, 10); + if (errno) + { + /* + * Couldn't parse the response for some reason. On the (few) + * tests I've done, the response is 213 <SIZE> with nothing else - + * maybe something a bit more resilient is necessary. It's not a + * fatal error, however. + */ + xfree (respline); + *size = 0; + return FTPOK; + } + + xfree (respline); + /* All OK. */ + return FTPOK; +} + +/* If URL's params are of the form "type=X", return character X. + Otherwise, return 'I' (the default type). */ +char +ftp_process_type (const char *params) +{ + if (params + && 0 == strncasecmp (params, "type=", 5) + && params[5] != '\0') + return c_toupper (params[5]); + else + return 'I'; +} |