release/src/router/busybox/networking/ftpgetput.c

   1 /* vi: set sw=4 ts=4: */
   2 /*
   3  * ftpget
   4  *
   5  * Mini implementation of FTP to retrieve a remote file.
   6  *
   7  * Copyright (C) 2002 Jeff Angielski, The PTR Group <jeff@theptrgroup.com>
   8  * Copyright (C) 2002 Glenn McGrath
   9  *
  10  * Based on wget.c by Chip Rosenthal Covad Communications
  11  * <chip@laserlink.net>
  12  *
  13  * Licensed under GPLv2 or later, see file LICENSE in this source tree.
  14  */
  15
  16 //usage:#define ftpget_trivial_usage
  17 //usage:       "[OPTIONS] HOST [LOCAL_FILE] REMOTE_FILE"
  18 //usage:#define ftpget_full_usage "\n\n"
  19 //usage:       "Download a file via FTP\n"
  20 //usage:        IF_FEATURE_FTPGETPUT_LONG_OPTIONS(
  21 //usage:     "\n        -c,--continue           Continue previous transfer"
  22 //usage:     "\n        -v,--verbose            Verbose"
  23 //usage:     "\n        -u,--username USER      Username"
  24 //usage:     "\n        -p,--password PASS      Password"
  25 //usage:     "\n        -P,--port NUM           Port"
  26 //usage:        )
  27 //usage:        IF_NOT_FEATURE_FTPGETPUT_LONG_OPTIONS(
  28 //usage:     "\n        -c      Continue previous transfer"
  29 //usage:     "\n        -v      Verbose"
  30 //usage:     "\n        -u USER Username"
  31 //usage:     "\n        -p PASS Password"
  32 //usage:     "\n        -P NUM  Port"
  33 //usage:        )
  34 //usage:
  35 //usage:#define ftpput_trivial_usage
  36 //usage:       "[OPTIONS] HOST [REMOTE_FILE] LOCAL_FILE"
  37 //usage:#define ftpput_full_usage "\n\n"
  38 //usage:       "Upload a file to a FTP server\n"
  39 //usage:        IF_FEATURE_FTPGETPUT_LONG_OPTIONS(
  40 //usage:     "\n        -v,--verbose            Verbose"
  41 //usage:     "\n        -u,--username USER      Username"
  42 //usage:     "\n        -p,--password PASS      Password"
  43 //usage:     "\n        -P,--port NUM           Port"
  44 //usage:        )
  45 //usage:        IF_NOT_FEATURE_FTPGETPUT_LONG_OPTIONS(
  46 //usage:     "\n        -v      Verbose"
  47 //usage:     "\n        -u USER Username"
  48 //usage:     "\n        -p PASS Password"
  49 //usage:     "\n        -P NUM  Port number"
  50 //usage:        )
  51
  52 #include "libbb.h"
  53
  54 struct globals {
  55         const char *user;
  56         const char *password;
  57         struct len_and_sockaddr *lsa;
  58         FILE *control_stream;
  59         int verbose_flag;
  60         int do_continue;
  61         char buf[4]; /* actually [BUFSZ] */
  62 } FIX_ALIASING;
  63 #define G (*(struct globals*)&bb_common_bufsiz1)
  64 enum { BUFSZ = COMMON_BUFSIZE - offsetof(struct globals, buf) };
  65 struct BUG_G_too_big {
  66         char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1];
  67 };
  68 #define user           (G.user          )
  69 #define password       (G.password      )
  70 #define lsa            (G.lsa           )
  71 #define control_stream (G.control_stream)
  72 #define verbose_flag   (G.verbose_flag  )
  73 #define do_continue    (G.do_continue   )
  74 #define buf            (G.buf           )
  75 #define INIT_G() do { } while (0)
  76
  77
  78 static void ftp_die(const char *msg) NORETURN;
  79 static void ftp_die(const char *msg)
  80 {
  81         char *cp = buf; /* buf holds peer's response */
  82
  83         /* Guard against garbage from remote server */
  84         while (*cp >= ' ' && *cp < '\x7f')
  85                 cp++;
  86         *cp = '\0';
  87         bb_error_msg_and_die("unexpected server response%s%s: %s",
  88                         (msg ? " to " : ""), (msg ? msg : ""), buf);
  89 }
  90
  91 static int ftpcmd(const char *s1, const char *s2)
  92 {
  93         unsigned n;
  94
  95         if (verbose_flag) {
  96                 bb_error_msg("cmd %s %s", s1, s2);
  97         }
  98
  99         if (s1) {
 100                 fprintf(control_stream, (s2 ? "%s %s\r\n" : "%s %s\r\n"+3),
 101                                                 s1, s2);
 102                 fflush(control_stream);
 103         }
 104
 105         do {
 106                 strcpy(buf, "EOF"); /* for ftp_die */
 107                 if (fgets(buf, BUFSZ - 2, control_stream) == NULL) {
 108                         ftp_die(NULL);
 109                 }
 110         } while (!isdigit(buf[0]) || buf[3] != ' ');
 111
 112         buf[3] = '\0';
 113         n = xatou(buf);
 114         buf[3] = ' ';
 115         return n;
 116 }
 117
 118 static void ftp_login(void)
 119 {
 120         /* Connect to the command socket */
 121         control_stream = fdopen(xconnect_stream(lsa), "r+");
 122         if (control_stream == NULL) {
 123                 /* fdopen failed - extremely unlikely */
 124                 bb_perror_nomsg_and_die();
 125         }
 126
 127         if (ftpcmd(NULL, NULL) != 220) {
 128                 ftp_die(NULL);
 129         }
 130
 131         /*  Login to the server */
 132         switch (ftpcmd("USER", user)) {
 133         case 230:
 134                 break;
 135         case 331:
 136                 if (ftpcmd("PASS", password) != 230) {
 137                         ftp_die("PASS");
 138                 }
 139                 break;
 140         default:
 141                 ftp_die("USER");
 142         }
 143
 144         ftpcmd("TYPE I", NULL);
 145 }
 146
 147 static int xconnect_ftpdata(void)
 148 {
 149         char *buf_ptr;
 150         unsigned port_num;
 151
 152 /*
 153 TODO: PASV command will not work for IPv6. RFC2428 describes
 154 IPv6-capable "extended PASV" - EPSV.
 155
 156 "EPSV [protocol]" asks server to bind to and listen on a data port
 157 in specified protocol. Protocol is 1 for IPv4, 2 for IPv6.
 158 If not specified, defaults to "same as used for control connection".
 159 If server understood you, it should answer "229 <some text>(|||port|)"
 160 where "|" are literal pipe chars and "port" is ASCII decimal port#.
 161
 162 There is also an IPv6-capable replacement for PORT (EPRT),
 163 but we don't need that.
 164
 165 NB: PASV may still work for some servers even over IPv6.
 166 For example, vsftp happily answers
 167 "227 Entering Passive Mode (0,0,0,0,n,n)" and proceeds as usual.
 168
 169 TODO2: need to stop ignoring IP address in PASV response.
 170 */
 171
 172         if (ftpcmd("PASV", NULL) != 227) {
 173                 ftp_die("PASV");
 174         }
 175
 176         /* Response is "NNN garbageN1,N2,N3,N4,P1,P2[)garbage]
 177          * Server's IP is N1.N2.N3.N4 (we ignore it)
 178          * Server's port for data connection is P1*256+P2 */
 179         buf_ptr = strrchr(buf, ')');
 180         if (buf_ptr) *buf_ptr = '\0';
 181
 182         buf_ptr = strrchr(buf, ',');
 183         *buf_ptr = '\0';
 184         port_num = xatoul_range(buf_ptr + 1, 0, 255);
 185
 186         buf_ptr = strrchr(buf, ',');
 187         *buf_ptr = '\0';
 188         port_num += xatoul_range(buf_ptr + 1, 0, 255) * 256;
 189
 190         set_nport(&lsa->u.sa, htons(port_num));
 191         return xconnect_stream(lsa);
 192 }
 193
 194 static int pump_data_and_QUIT(int from, int to)
 195 {
 196         /* copy the file */
 197         if (bb_copyfd_eof(from, to) == -1) {
 198                 /* error msg is already printed by bb_copyfd_eof */
 199                 return EXIT_FAILURE;
 200         }
 201
 202         /* close data connection */
 203         close(from); /* don't know which one is that, so we close both */
 204         close(to);
 205
 206         /* does server confirm that transfer is finished? */
 207         if (ftpcmd(NULL, NULL) != 226) {
 208                 ftp_die(NULL);
 209         }
 210         ftpcmd("QUIT", NULL);
 211
 212         return EXIT_SUCCESS;
 213 }
 214
 215 #if !ENABLE_FTPGET
 216 int ftp_receive(const char *local_path, char *server_path);
 217 #else
 218 static
 219 int ftp_receive(const char *local_path, char *server_path)
 220 {
 221         int fd_data;
 222         int fd_local = -1;
 223         off_t beg_range = 0;
 224
 225         /* connect to the data socket */
 226         fd_data = xconnect_ftpdata();
 227
 228         if (ftpcmd("SIZE", server_path) != 213) {
 229                 do_continue = 0;
 230         }
 231
 232         if (LONE_DASH(local_path)) {
 233                 fd_local = STDOUT_FILENO;
 234                 do_continue = 0;
 235         }
 236
 237         if (do_continue) {
 238                 struct stat sbuf;
 239                 /* lstat would be wrong here! */
 240                 if (stat(local_path, &sbuf) < 0) {
 241                         bb_perror_msg_and_die("stat");
 242                 }
 243                 if (sbuf.st_size > 0) {
 244                         beg_range = sbuf.st_size;
 245                 } else {
 246                         do_continue = 0;
 247                 }
 248         }
 249
 250         if (do_continue) {
 251                 sprintf(buf, "REST %"OFF_FMT"u", beg_range);
 252                 if (ftpcmd(buf, NULL) != 350) {
 253                         do_continue = 0;
 254                 }
 255         }
 256
 257         if (ftpcmd("RETR", server_path) > 150) {
 258                 ftp_die("RETR");
 259         }
 260
 261         /* create local file _after_ we know that remote file exists */
 262         if (fd_local == -1) {
 263                 fd_local = xopen(local_path,
 264                         do_continue ? (O_APPEND | O_WRONLY)
 265                                     : (O_CREAT | O_TRUNC | O_WRONLY)
 266                 );
 267         }
 268
 269         return pump_data_and_QUIT(fd_data, fd_local);
 270 }
 271 #endif
 272
 273 #if !ENABLE_FTPPUT
 274 int ftp_send(const char *server_path, char *local_path);
 275 #else
 276 static
 277 int ftp_send(const char *server_path, char *local_path)
 278 {
 279         int fd_data;
 280         int fd_local;
 281         int response;
 282
 283         /* connect to the data socket */
 284         fd_data = xconnect_ftpdata();
 285
 286         /* get the local file */
 287         fd_local = STDIN_FILENO;
 288         if (NOT_LONE_DASH(local_path))
 289                 fd_local = xopen(local_path, O_RDONLY);
 290
 291         response = ftpcmd("STOR", server_path);
 292         switch (response) {
 293         case 125:
 294         case 150:
 295                 break;
 296         default:
 297                 ftp_die("STOR");
 298         }
 299
 300         return pump_data_and_QUIT(fd_local, fd_data);
 301 }
 302 #endif
 303
 304 #if ENABLE_FEATURE_FTPGETPUT_LONG_OPTIONS
 305 static const char ftpgetput_longopts[] ALIGN1 =
 306         "continue\0" Required_argument "c"
 307         "verbose\0"  No_argument       "v"
 308         "username\0" Required_argument "u"
 309         "password\0" Required_argument "p"
 310         "port\0"     Required_argument "P"
 311         ;
 312 #endif
 313
 314 int ftpgetput_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
 315 int ftpgetput_main(int argc UNUSED_PARAM, char **argv)
 316 {
 317         const char *port = "ftp";
 318         /* socket to ftp server */
 319
 320 #if ENABLE_FTPPUT && !ENABLE_FTPGET
 321 # define ftp_action ftp_send
 322 #elif ENABLE_FTPGET && !ENABLE_FTPPUT
 323 # define ftp_action ftp_receive
 324 #else
 325         int (*ftp_action)(const char *, char *) = ftp_send;
 326
 327         /* Check to see if the command is ftpget or ftput */
 328         if (applet_name[3] == 'g') {
 329                 ftp_action = ftp_receive;
 330         }
 331 #endif
 332
 333         INIT_G();
 334         /* Set default values */
 335         user = "anonymous";
 336         password = "busybox@";
 337
 338         /*
 339          * Decipher the command line
 340          */
 341 #if ENABLE_FEATURE_FTPGETPUT_LONG_OPTIONS
 342         applet_long_options = ftpgetput_longopts;
 343 #endif
 344         opt_complementary = "-2:vv:cc"; /* must have 2 to 3 params; -v and -c count */
 345         getopt32(argv, "cvu:p:P:", &user, &password, &port,
 346                                         &verbose_flag, &do_continue);
 347         argv += optind;
 348
 349         /* We want to do exactly _one_ DNS lookup, since some
 350          * sites (i.e. ftp.us.debian.org) use round-robin DNS
 351          * and we want to connect to only one IP... */
 352         lsa = xhost2sockaddr(argv[0], bb_lookup_port(port, "tcp", 21));
 353         if (verbose_flag) {
 354                 printf("Connecting to %s (%s)\n", argv[0],
 355                         xmalloc_sockaddr2dotted(&lsa->u.sa));
 356         }
 357
 358         ftp_login();
 359         return ftp_action(argv[1], argv[2] ? argv[2] : argv[1]);
 360 }