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- /* vi: set sw=4 ts=4: */
- /*
- * A simple tftp client/server for busybox.
- * Tries to follow RFC1350.
- * Only "octet" mode supported.
- * Optional blocksize negotiation (RFC2347 + RFC2348)
- *
- * Copyright (C) 2001 Magnus Damm <damm@opensource.se>
- *
- * Parts of the code based on:
- *
- * atftp: Copyright (C) 2000 Jean-Pierre Lefebvre <helix@step.polymtl.ca>
- * and Remi Lefebvre <remi@debian.org>
- *
- * utftp: Copyright (C) 1999 Uwe Ohse <uwe@ohse.de>
- *
- * tftpd added by Denys Vlasenko & Vladimir Dronnikov
- *
- * Licensed under GPLv2 or later, see file LICENSE in this source tree.
- */
- //config:config TFTP
- //config: bool "tftp (11 kb)"
- //config: default y
- //config: help
- //config: Trivial File Transfer Protocol client. TFTP is usually used
- //config: for simple, small transfers such as a root image
- //config: for a network-enabled bootloader.
- //config:
- //config:config FEATURE_TFTP_PROGRESS_BAR
- //config: bool "Enable progress bar"
- //config: default y
- //config: depends on TFTP
- //config:
- //config:config FEATURE_TFTP_HPA_COMPAT
- //config: bool "tftp-hpa compat (support -c get/put FILE)"
- //config: default y
- //config: depends on TFTP
- //config:
- //config:config TFTPD
- //config: bool "tftpd (10 kb)"
- //config: default y
- //config: help
- //config: Trivial File Transfer Protocol server.
- //config: It expects that stdin is a datagram socket and a packet
- //config: is already pending on it. It will exit after one transfer.
- //config: In other words: it should be run from inetd in nowait mode,
- //config: or from udpsvd. Example: "udpsvd -E 0 69 tftpd DIR"
- //config:
- //config:config FEATURE_TFTP_GET
- //config: bool "Enable 'tftp get' and/or tftpd upload code"
- //config: default y
- //config: depends on TFTP || TFTPD
- //config: help
- //config: Add support for the GET command within the TFTP client. This allows
- //config: a client to retrieve a file from a TFTP server.
- //config: Also enable upload support in tftpd, if tftpd is selected.
- //config:
- //config: Note: this option does _not_ make tftpd capable of download
- //config: (the usual operation people need from it)!
- //config:
- //config:config FEATURE_TFTP_PUT
- //config: bool "Enable 'tftp put' and/or tftpd download code"
- //config: default y
- //config: depends on TFTP || TFTPD
- //config: help
- //config: Add support for the PUT command within the TFTP client. This allows
- //config: a client to transfer a file to a TFTP server.
- //config: Also enable download support in tftpd, if tftpd is selected.
- //config:
- //config:config FEATURE_TFTP_BLOCKSIZE
- //config: bool "Enable 'blksize' and 'tsize' protocol options"
- //config: default y
- //config: depends on TFTP || TFTPD
- //config: help
- //config: Allow tftp to specify block size, and tftpd to understand
- //config: "blksize" and "tsize" options.
- //config:
- //config:config TFTP_DEBUG
- //config: bool "Enable debug"
- //config: default n
- //config: depends on TFTP || TFTPD
- //config: help
- //config: Make tftp[d] print debugging messages on stderr.
- //config: This is useful if you are diagnosing a bug in tftp[d].
- //applet:#if ENABLE_FEATURE_TFTP_GET || ENABLE_FEATURE_TFTP_PUT
- //applet:IF_TFTP(APPLET(tftp, BB_DIR_USR_BIN, BB_SUID_DROP))
- //applet:IF_TFTPD(APPLET(tftpd, BB_DIR_USR_SBIN, BB_SUID_DROP))
- //applet:#endif
- //kbuild:lib-$(CONFIG_TFTP) += tftp.o
- //kbuild:lib-$(CONFIG_TFTPD) += tftp.o
- //usage:#define tftp_trivial_usage
- //usage: "[OPTIONS] HOST [PORT]"
- //usage:#define tftp_full_usage "\n\n"
- //usage: "Transfer a file from/to tftp server\n"
- //usage: "\n -l FILE Local FILE"
- //usage: "\n -r FILE Remote FILE"
- //usage: IF_FEATURE_TFTP_GET(
- //usage: "\n -g Get file"
- //usage: )
- //usage: IF_FEATURE_TFTP_PUT(
- //usage: "\n -p Put file"
- //usage: )
- //usage: IF_FEATURE_TFTP_BLOCKSIZE(
- //usage: "\n -b SIZE Transfer blocks of SIZE octets"
- //usage: )
- ///////: "\n -m STR Accepted and ignored ('-m binary' compat with tftp-hpa 5.2)"
- //usage:
- //usage:#define tftpd_trivial_usage
- //usage: "[-crl] [-u USER] [DIR]"
- //usage:#define tftpd_full_usage "\n\n"
- //usage: "Transfer a file on tftp client's request\n"
- //usage: "\n"
- //usage: "tftpd should be used as an inetd service.\n"
- //usage: "tftpd's line for inetd.conf:\n"
- //usage: " 69 dgram udp nowait root tftpd tftpd -l /files/to/serve\n"
- //usage: "It also can be ran from udpsvd:\n"
- //usage: " udpsvd -vE 0.0.0.0 69 tftpd /files/to/serve\n"
- //usage: "\n -r Prohibit upload"
- //usage: "\n -c Allow file creation via upload"
- //usage: "\n -u Access files as USER"
- //usage: "\n -l Log to syslog (inetd mode requires this)"
- #include "libbb.h"
- #include "common_bufsiz.h"
- #include <syslog.h>
- #if ENABLE_FEATURE_TFTP_GET || ENABLE_FEATURE_TFTP_PUT
- #define TFTP_BLKSIZE_DEFAULT 512 /* according to RFC 1350, don't change */
- #define TFTP_BLKSIZE_DEFAULT_STR "512"
- /* Was 50 ms but users asked to bump it up a bit */
- #define TFTP_TIMEOUT_MS 100
- #define TFTP_MAXTIMEOUT_MS 2000
- #define TFTP_NUM_RETRIES 12 /* number of backed-off retries */
- /* opcodes we support */
- #define TFTP_RRQ 1
- #define TFTP_WRQ 2
- #define TFTP_DATA 3
- #define TFTP_ACK 4
- #define TFTP_ERROR 5
- #define TFTP_OACK 6
- /* error codes sent over network (we use only 0, 1, 3 and 8) */
- /* generic (error message is included in the packet) */
- #define ERR_UNSPEC 0
- #define ERR_NOFILE 1
- #define ERR_ACCESS 2
- /* disk full or allocation exceeded */
- #define ERR_WRITE 3
- #define ERR_OP 4
- #define ERR_BAD_ID 5
- #define ERR_EXIST 6
- #define ERR_BAD_USER 7
- #define ERR_BAD_OPT 8
- /* masks coming from getopt32 */
- enum {
- TFTP_OPT_GET = (1 << 0),
- TFTP_OPT_PUT = (1 << 1),
- /* pseudo option: if set, it's tftpd */
- TFTPD_OPT = (1 << 7) * ENABLE_TFTPD,
- TFTPD_OPT_r = (1 << 8) * ENABLE_TFTPD,
- TFTPD_OPT_c = (1 << 9) * ENABLE_TFTPD,
- TFTPD_OPT_u = (1 << 10) * ENABLE_TFTPD,
- TFTPD_OPT_l = (1 << 11) * ENABLE_TFTPD,
- };
- #if ENABLE_FEATURE_TFTP_GET && !ENABLE_FEATURE_TFTP_PUT
- #define IF_GETPUT(...)
- #define CMD_GET(cmd) 1
- #define CMD_PUT(cmd) 0
- #elif !ENABLE_FEATURE_TFTP_GET && ENABLE_FEATURE_TFTP_PUT
- #define IF_GETPUT(...)
- #define CMD_GET(cmd) 0
- #define CMD_PUT(cmd) 1
- #else
- #define IF_GETPUT(...) __VA_ARGS__
- #define CMD_GET(cmd) ((cmd) & TFTP_OPT_GET)
- #define CMD_PUT(cmd) ((cmd) & TFTP_OPT_PUT)
- #endif
- /* NB: in the code below
- * CMD_GET(cmd) and CMD_PUT(cmd) are mutually exclusive
- */
- struct globals {
- /* u16 TFTP_ERROR; u16 reason; both network-endian, then error text: */
- uint8_t error_pkt[4 + 32];
- struct passwd *pw;
- /* Used in tftpd_main() for initial packet */
- /* Some HP PA-RISC firmware always sends fixed 516-byte requests */
- char block_buf[516];
- char block_buf_tail[1];
- #if ENABLE_FEATURE_TFTP_PROGRESS_BAR
- off_t pos;
- off_t size;
- const char *file;
- bb_progress_t pmt;
- #endif
- } FIX_ALIASING;
- #define G (*(struct globals*)bb_common_bufsiz1)
- #define INIT_G() do { \
- setup_common_bufsiz(); \
- BUILD_BUG_ON(sizeof(G) > COMMON_BUFSIZE); \
- } while (0)
- #define G_error_pkt_reason (G.error_pkt[3])
- #define G_error_pkt_str ((char*)(G.error_pkt + 4))
- #if ENABLE_FEATURE_TFTP_PROGRESS_BAR && ENABLE_FEATURE_TFTP_BLOCKSIZE
- static void tftp_progress_update(void)
- {
- bb_progress_update(&G.pmt, 0, G.pos, G.size);
- }
- static void tftp_progress_init(void)
- {
- bb_progress_init(&G.pmt, G.file);
- tftp_progress_update();
- }
- static void tftp_progress_done(void)
- {
- if (is_bb_progress_inited(&G.pmt)) {
- tftp_progress_update();
- bb_putchar_stderr('\n');
- bb_progress_free(&G.pmt);
- }
- }
- #else
- # define tftp_progress_update() ((void)0)
- # define tftp_progress_init() ((void)0)
- # define tftp_progress_done() ((void)0)
- #endif
- #if ENABLE_FEATURE_TFTP_BLOCKSIZE
- static int tftp_blksize_check(const char *blksize_str, int maxsize)
- {
- /* Check if the blksize is valid:
- * RFC2348 says between 8 and 65464,
- * but our implementation makes it impossible
- * to use blksizes smaller than 22 octets. */
- unsigned blksize = bb_strtou(blksize_str, NULL, 10);
- if (errno
- || (blksize < 24) || (blksize > maxsize)
- ) {
- bb_error_msg("bad blocksize '%s'", blksize_str);
- return -1;
- }
- # if ENABLE_TFTP_DEBUG
- bb_info_msg("using blksize %u", blksize);
- # endif
- return blksize;
- }
- static char *tftp_get_option(const char *option, char *buf, int len)
- {
- int opt_val = 0;
- int opt_found = 0;
- int k;
- /* buf points to:
- * "opt_name<NUL>opt_val<NUL>opt_name2<NUL>opt_val2<NUL>..." */
- while (len > 0) {
- /* Make sure options are terminated correctly */
- for (k = 0; k < len; k++) {
- if (buf[k] == '\0') {
- goto nul_found;
- }
- }
- return NULL;
- nul_found:
- if (opt_val == 0) { /* it's "name" part */
- if (strcasecmp(buf, option) == 0) {
- opt_found = 1;
- }
- } else if (opt_found) {
- return buf;
- }
- k++;
- buf += k;
- len -= k;
- opt_val ^= 1;
- }
- return NULL;
- }
- #endif
- static int tftp_protocol(
- /* NULL if tftp, !NULL if tftpd: */
- len_and_sockaddr *our_lsa,
- len_and_sockaddr *peer_lsa,
- const char *local_file
- IF_TFTP(, const char *remote_file)
- #if !ENABLE_TFTP
- # define remote_file NULL
- #endif
- /* 1 for tftp; 1/0 for tftpd depending whether client asked about it: */
- IF_FEATURE_TFTP_BLOCKSIZE(, int want_transfer_size)
- IF_FEATURE_TFTP_BLOCKSIZE(, int blksize))
- {
- #if !ENABLE_FEATURE_TFTP_BLOCKSIZE
- enum { blksize = TFTP_BLKSIZE_DEFAULT };
- #endif
- struct pollfd pfd[1];
- #define socket_fd (pfd[0].fd)
- int len;
- int send_len;
- IF_FEATURE_TFTP_BLOCKSIZE(smallint expect_OACK = 0;)
- smallint finished = 0;
- uint16_t opcode;
- uint16_t block_nr;
- uint16_t recv_blk;
- int open_mode, local_fd;
- int retries, waittime_ms;
- int io_bufsize = blksize + 4;
- char *cp;
- /* Can't use RESERVE_CONFIG_BUFFER here since the allocation
- * size varies meaning BUFFERS_GO_ON_STACK would fail.
- *
- * We must keep the transmit and receive buffers separate
- * in case we rcv a garbage pkt - we need to rexmit the last pkt.
- */
- char *xbuf = xmalloc(io_bufsize);
- char *rbuf = xmalloc(io_bufsize);
- socket_fd = xsocket(peer_lsa->u.sa.sa_family, SOCK_DGRAM, 0);
- setsockopt_reuseaddr(socket_fd);
- if (!ENABLE_TFTP || our_lsa) { /* tftpd */
- /* Create a socket which is:
- * 1. bound to IP:port peer sent 1st datagram to,
- * 2. connected to peer's IP:port
- * This way we will answer from the IP:port peer
- * expects, will not get any other packets on
- * the socket, and also plain read/write will work. */
- xbind(socket_fd, &our_lsa->u.sa, our_lsa->len);
- xconnect(socket_fd, &peer_lsa->u.sa, peer_lsa->len);
- /* Is there an error already? Send pkt and bail out */
- if (G_error_pkt_reason || G_error_pkt_str[0])
- goto send_err_pkt;
- if (G.pw) {
- change_identity(G.pw); /* initgroups, setgid, setuid */
- }
- }
- /* Prepare open mode */
- if (CMD_PUT(option_mask32)) {
- open_mode = O_RDONLY;
- } else {
- open_mode = O_WRONLY | O_TRUNC | O_CREAT;
- #if ENABLE_TFTPD
- if ((option_mask32 & (TFTPD_OPT+TFTPD_OPT_c)) == TFTPD_OPT) {
- /* tftpd without -c */
- open_mode = O_WRONLY | O_TRUNC;
- }
- #endif
- }
- /* Examples of network traffic.
- * Note two cases when ACKs with block# of 0 are sent.
- *
- * Download without options:
- * tftp -> "\0\1FILENAME\0octet\0"
- * "\0\3\0\1FILEDATA..." <- tftpd
- * tftp -> "\0\4\0\1"
- * ...
- * Download with option of blksize 16384:
- * tftp -> "\0\1FILENAME\0octet\0blksize\00016384\0"
- * "\0\6blksize\00016384\0" <- tftpd
- * tftp -> "\0\4\0\0"
- * "\0\3\0\1FILEDATA..." <- tftpd
- * tftp -> "\0\4\0\1"
- * ...
- * Upload without options:
- * tftp -> "\0\2FILENAME\0octet\0"
- * "\0\4\0\0" <- tftpd
- * tftp -> "\0\3\0\1FILEDATA..."
- * "\0\4\0\1" <- tftpd
- * ...
- * Upload with option of blksize 16384:
- * tftp -> "\0\2FILENAME\0octet\0blksize\00016384\0"
- * "\0\6blksize\00016384\0" <- tftpd
- * tftp -> "\0\3\0\1FILEDATA..."
- * "\0\4\0\1" <- tftpd
- * ...
- */
- block_nr = 1;
- cp = xbuf + 2;
- if (!ENABLE_TFTP || our_lsa) { /* tftpd */
- /* Open file (must be after changing user) */
- local_fd = open(local_file, open_mode, 0666);
- if (local_fd < 0) {
- G_error_pkt_reason = ERR_NOFILE;
- strcpy(G_error_pkt_str, "can't open file");
- goto send_err_pkt;
- }
- /* gcc 4.3.1 would NOT optimize it out as it should! */
- #if ENABLE_FEATURE_TFTP_BLOCKSIZE
- if (blksize != TFTP_BLKSIZE_DEFAULT || want_transfer_size) {
- /* Create and send OACK packet. */
- /* For the download case, block_nr is still 1 -
- * we expect 1st ACK from peer to be for (block_nr-1),
- * that is, for "block 0" which is our OACK pkt */
- opcode = TFTP_OACK;
- goto add_blksize_opt;
- }
- #endif
- if (CMD_GET(option_mask32)) {
- /* It's upload and we don't send OACK.
- * We must ACK 1st packet (with filename)
- * as if it is "block 0" */
- block_nr = 0;
- }
- } else { /* tftp */
- /* Open file (must be after changing user) */
- local_fd = CMD_GET(option_mask32) ? STDOUT_FILENO : STDIN_FILENO;
- if (NOT_LONE_DASH(local_file))
- local_fd = xopen(local_file, open_mode);
- /* Removing #if, or using if() statement instead of #if may lead to
- * "warning: null argument where non-null required": */
- #if ENABLE_TFTP
- /* tftp */
- /* We can't (and don't really need to) bind the socket:
- * we don't know from which local IP datagrams will be sent,
- * but kernel will pick the same IP every time (unless routing
- * table is changed), thus peer will see dgrams consistently
- * coming from the same IP.
- * We would like to connect the socket, but since peer's
- * UDP code can be less perfect than ours, _peer's_ IP:port
- * in replies may differ from IP:port we used to send
- * our first packet. We can connect() only when we get
- * first reply. */
- /* build opcode */
- opcode = TFTP_WRQ;
- if (CMD_GET(option_mask32)) {
- opcode = TFTP_RRQ;
- }
- /* add filename and mode */
- /* fill in packet if the filename fits into xbuf */
- len = strlen(remote_file) + 1;
- if (2 + len + sizeof("octet") >= io_bufsize) {
- bb_error_msg("remote filename is too long");
- goto ret;
- }
- strcpy(cp, remote_file);
- cp += len;
- /* add "mode" part of the packet */
- strcpy(cp, "octet");
- cp += sizeof("octet");
- # if ENABLE_FEATURE_TFTP_BLOCKSIZE
- if (blksize == TFTP_BLKSIZE_DEFAULT && !want_transfer_size)
- goto send_pkt;
- /* Need to add option to pkt */
- if ((&xbuf[io_bufsize - 1] - cp) < sizeof("blksize NNNNN tsize ") + sizeof(off_t)*3) {
- bb_error_msg("remote filename is too long");
- goto ret;
- }
- expect_OACK = 1;
- # endif
- #endif /* ENABLE_TFTP */
- #if ENABLE_FEATURE_TFTP_BLOCKSIZE
- add_blksize_opt:
- if (blksize != TFTP_BLKSIZE_DEFAULT) {
- /* add "blksize", <nul>, blksize, <nul> */
- strcpy(cp, "blksize");
- cp += sizeof("blksize");
- cp += snprintf(cp, 6, "%d", blksize) + 1;
- }
- if (want_transfer_size) {
- /* add "tsize", <nul>, size, <nul> (see RFC2349) */
- /* if tftp and downloading, we send "0" (since we opened local_fd with O_TRUNC)
- * and this makes server to send "tsize" option with the size */
- /* if tftp and uploading, we send file size (maybe dont, to not confuse old servers???) */
- /* if tftpd and downloading, we are answering to client's request */
- /* if tftpd and uploading: !want_transfer_size, this code is not executed */
- struct stat st;
- strcpy(cp, "tsize");
- cp += sizeof("tsize");
- st.st_size = 0;
- fstat(local_fd, &st);
- cp += sprintf(cp, "%"OFF_FMT"u", (off_t)st.st_size) + 1;
- # if ENABLE_FEATURE_TFTP_PROGRESS_BAR
- /* Save for progress bar. If 0 (tftp downloading),
- * we look at server's reply later */
- G.size = st.st_size;
- if (remote_file && st.st_size)
- tftp_progress_init();
- # endif
- }
- #endif
- /* First packet is built, so skip packet generation */
- goto send_pkt;
- }
- /* Using mostly goto's - continue/break will be less clear
- * in where we actually jump to */
- while (1) {
- /* Build ACK or DATA */
- cp = xbuf + 2;
- *((uint16_t*)cp) = htons(block_nr);
- cp += 2;
- block_nr++;
- opcode = TFTP_ACK;
- if (CMD_PUT(option_mask32)) {
- opcode = TFTP_DATA;
- len = full_read(local_fd, cp, blksize);
- if (len < 0) {
- goto send_read_err_pkt;
- }
- if (len != blksize) {
- finished = 1;
- }
- cp += len;
- IF_FEATURE_TFTP_PROGRESS_BAR(G.pos += len;)
- }
- send_pkt:
- /* Send packet */
- *((uint16_t*)xbuf) = htons(opcode); /* fill in opcode part */
- send_len = cp - xbuf;
- /* NB: send_len value is preserved in code below
- * for potential resend */
- retries = TFTP_NUM_RETRIES; /* re-initialize */
- waittime_ms = TFTP_TIMEOUT_MS;
- send_again:
- #if ENABLE_TFTP_DEBUG
- fprintf(stderr, "sending %u bytes\n", send_len);
- for (cp = xbuf; cp < &xbuf[send_len]; cp++)
- fprintf(stderr, "%02x ", (unsigned char) *cp);
- fprintf(stderr, "\n");
- #endif
- xsendto(socket_fd, xbuf, send_len, &peer_lsa->u.sa, peer_lsa->len);
- #if ENABLE_FEATURE_TFTP_PROGRESS_BAR
- if (is_bb_progress_inited(&G.pmt))
- tftp_progress_update();
- #endif
- /* Was it final ACK? then exit */
- if (finished && (opcode == TFTP_ACK))
- goto ret;
- recv_again:
- /* Receive packet */
- /*pfd[0].fd = socket_fd;*/
- pfd[0].events = POLLIN;
- switch (safe_poll(pfd, 1, waittime_ms)) {
- default:
- /*bb_perror_msg("poll"); - done in safe_poll */
- goto ret;
- case 0:
- retries--;
- if (retries == 0) {
- tftp_progress_done();
- bb_error_msg("timeout");
- goto ret; /* no err packet sent */
- }
- /* exponential backoff with limit */
- waittime_ms += waittime_ms/2;
- if (waittime_ms > TFTP_MAXTIMEOUT_MS) {
- waittime_ms = TFTP_MAXTIMEOUT_MS;
- }
- goto send_again; /* resend last sent pkt */
- case 1:
- if (!our_lsa) {
- /* tftp (not tftpd!) receiving 1st packet */
- our_lsa = ((void*)(ptrdiff_t)-1); /* not NULL */
- len = recvfrom(socket_fd, rbuf, io_bufsize, 0,
- &peer_lsa->u.sa, &peer_lsa->len);
- /* Our first dgram went to port 69
- * but reply may come from different one.
- * Remember and use this new port (and IP) */
- if (len >= 0)
- xconnect(socket_fd, &peer_lsa->u.sa, peer_lsa->len);
- } else {
- /* tftpd, or not the very first packet:
- * socket is connect()ed, can just read from it. */
- /* Don't full_read()!
- * This is not TCP, one read == one pkt! */
- len = safe_read(socket_fd, rbuf, io_bufsize);
- }
- if (len < 0) {
- goto send_read_err_pkt;
- }
- if (len < 4) { /* too small? */
- goto recv_again;
- }
- }
- /* Process recv'ed packet */
- opcode = ntohs( ((uint16_t*)rbuf)[0] );
- recv_blk = ntohs( ((uint16_t*)rbuf)[1] );
- #if ENABLE_TFTP_DEBUG
- fprintf(stderr, "received %d bytes: %04x %04x\n", len, opcode, recv_blk);
- #endif
- if (opcode == TFTP_ERROR) {
- static const char errcode_str[] ALIGN1 =
- "\0"
- "file not found\0"
- "access violation\0"
- "disk full\0"
- "bad operation\0"
- "unknown transfer id\0"
- "file already exists\0"
- "no such user\0"
- "bad option";
- const char *msg = "";
- if (len > 4 && rbuf[4] != '\0') {
- msg = &rbuf[4];
- rbuf[io_bufsize - 1] = '\0'; /* paranoia */
- } else if (recv_blk <= 8) {
- msg = nth_string(errcode_str, recv_blk);
- }
- bb_error_msg("server error: (%u) %s", recv_blk, msg);
- goto ret;
- }
- #if ENABLE_FEATURE_TFTP_BLOCKSIZE
- if (expect_OACK) {
- expect_OACK = 0;
- if (opcode == TFTP_OACK) {
- /* server seems to support options */
- char *res;
- res = tftp_get_option("blksize", &rbuf[2], len - 2);
- if (res) {
- blksize = tftp_blksize_check(res, blksize);
- if (blksize < 0) {
- G_error_pkt_reason = ERR_BAD_OPT;
- goto send_err_pkt;
- }
- io_bufsize = blksize + 4;
- }
- # if ENABLE_FEATURE_TFTP_PROGRESS_BAR
- if (remote_file && G.size == 0) { /* if we don't know it yet */
- res = tftp_get_option("tsize", &rbuf[2], len - 2);
- if (res) {
- G.size = bb_strtoull(res, NULL, 10);
- if (G.size)
- tftp_progress_init();
- }
- }
- # endif
- if (CMD_GET(option_mask32)) {
- /* We'll send ACK for OACK,
- * such ACK has "block no" of 0 */
- block_nr = 0;
- }
- continue;
- }
- /* rfc2347:
- * "An option not acknowledged by the server
- * must be ignored by the client and server
- * as if it were never requested." */
- if (blksize != TFTP_BLKSIZE_DEFAULT)
- bb_error_msg("falling back to blocksize "TFTP_BLKSIZE_DEFAULT_STR);
- blksize = TFTP_BLKSIZE_DEFAULT;
- io_bufsize = TFTP_BLKSIZE_DEFAULT + 4;
- }
- #endif
- /* block_nr is already advanced to next block# we expect
- * to get / block# we are about to send next time */
- if (CMD_GET(option_mask32) && (opcode == TFTP_DATA)) {
- if (recv_blk == block_nr) {
- int sz = full_write(local_fd, &rbuf[4], len - 4);
- if (sz != len - 4) {
- strcpy(G_error_pkt_str, bb_msg_write_error);
- G_error_pkt_reason = ERR_WRITE;
- goto send_err_pkt;
- }
- if (sz != blksize) {
- finished = 1;
- }
- IF_FEATURE_TFTP_PROGRESS_BAR(G.pos += sz;)
- continue; /* send ACK */
- }
- /* Disabled to cope with servers with Sorcerer's Apprentice Syndrome */
- #if 0
- if (recv_blk == (block_nr - 1)) {
- /* Server lost our TFTP_ACK. Resend it */
- block_nr = recv_blk;
- continue;
- }
- #endif
- }
- if (CMD_PUT(option_mask32) && (opcode == TFTP_ACK)) {
- /* did peer ACK our last DATA pkt? */
- if (recv_blk == (uint16_t) (block_nr - 1)) {
- if (finished)
- goto ret;
- continue; /* send next block */
- }
- }
- /* Awww... recv'd packet is not recognized! */
- goto recv_again;
- /* why recv_again? - rfc1123 says:
- * "The sender (i.e., the side originating the DATA packets)
- * must never resend the current DATA packet on receipt
- * of a duplicate ACK".
- * DATA pkts are resent ONLY on timeout.
- * Thus "goto send_again" will ba a bad mistake above.
- * See:
- * http://en.wikipedia.org/wiki/Sorcerer's_Apprentice_Syndrome
- */
- } /* end of "while (1)" */
- ret:
- if (ENABLE_FEATURE_CLEAN_UP) {
- close(local_fd);
- close(socket_fd);
- free(xbuf);
- free(rbuf);
- }
- return finished == 0; /* returns 1 on failure */
- send_read_err_pkt:
- strcpy(G_error_pkt_str, bb_msg_read_error);
- send_err_pkt:
- if (G_error_pkt_str[0])
- bb_error_msg("%s", G_error_pkt_str);
- G.error_pkt[1] = TFTP_ERROR;
- xsendto(socket_fd, G.error_pkt, 4 + 1 + strlen(G_error_pkt_str),
- &peer_lsa->u.sa, peer_lsa->len);
- return EXIT_FAILURE;
- #undef remote_file
- }
- #if ENABLE_TFTP
- int tftp_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
- int tftp_main(int argc UNUSED_PARAM, char **argv)
- {
- len_and_sockaddr *peer_lsa;
- const char *local_file = NULL;
- const char *remote_file = NULL;
- # if ENABLE_FEATURE_TFTP_BLOCKSIZE
- const char *blksize_str = TFTP_BLKSIZE_DEFAULT_STR;
- int blksize;
- # endif
- int result;
- int port;
- IF_GETPUT(int opt;)
- INIT_G();
- if (ENABLE_FEATURE_TFTP_HPA_COMPAT) {
- /* As of 2019, common tftp client in Linux distros
- * is one maintained by H. Peter Anvin:
- * I've seen "tftp-hpa 5.2" version.
- * Make the following command work:
- * "tftp HOST [PORT] -m binary -c get/put FILE"
- * by mangling it into "....... -g/-p -r FILE"
- * and accepting and ignoring -m STR option.
- */
- unsigned i = 1;
- while (argv[i]) {
- /* Accept not only -c, but also
- * -lc, -cl, -llcclcllcc etc:
- * "-l Literal mode (do not recognize HOST:FILE)"
- * since we do not recognize that syntax anyway,
- * might as well allow the option.
- */
- if (argv[i][0] == '-' && strchr(argv[i], 'c')
- /*&& argv[i][1+strspn(argv[i]+1, "lc")] == '\0'*/
- ) {
- if (!argv[++i])
- break;
- if (strcmp(argv[i], "get") == 0) {
- argv[i-1] = (char*)"-g";
- argv[i] = (char*)"-r";
- break;
- }
- if (strcmp(argv[i], "put") == 0) {
- argv[i-1] = (char*)"-p";
- argv[i] = (char*)"-r";
- break;
- }
- }
- i++;
- }
- }
- IF_GETPUT(opt =) getopt32(argv, "^"
- IF_FEATURE_TFTP_GET("g") IF_FEATURE_TFTP_PUT("p")
- "l:r:" IF_FEATURE_TFTP_BLOCKSIZE("b:")
- IF_FEATURE_TFTP_HPA_COMPAT("m:")
- "\0"
- /* -p or -g is mandatory, and they are mutually exclusive */
- IF_FEATURE_TFTP_GET("g:") IF_FEATURE_TFTP_PUT("p:")
- IF_GETPUT("g--p:p--g:"),
- &local_file, &remote_file
- IF_FEATURE_TFTP_BLOCKSIZE(, &blksize_str)
- IF_FEATURE_TFTP_HPA_COMPAT(, NULL)
- );
- argv += optind;
- # if ENABLE_FEATURE_TFTP_BLOCKSIZE
- /* Check if the blksize is valid:
- * RFC2348 says between 8 and 65464 */
- blksize = tftp_blksize_check(blksize_str, 65564);
- if (blksize < 0) {
- //bb_error_msg("bad block size");
- return EXIT_FAILURE;
- }
- # endif
- if (remote_file) {
- if (!local_file) {
- const char *slash = strrchr(remote_file, '/');
- local_file = slash ? slash + 1 : remote_file;
- }
- } else {
- remote_file = local_file;
- }
- /* Error if filename or host is not known */
- if (!remote_file || !argv[0])
- bb_show_usage();
- port = bb_lookup_port(argv[1], "udp", 69);
- peer_lsa = xhost2sockaddr(argv[0], port);
- # if ENABLE_TFTP_DEBUG
- fprintf(stderr, "using server '%s', remote_file '%s', local_file '%s'\n",
- xmalloc_sockaddr2dotted(&peer_lsa->u.sa),
- remote_file, local_file);
- # endif
- # if ENABLE_FEATURE_TFTP_PROGRESS_BAR
- G.file = remote_file;
- # endif
- result = tftp_protocol(
- NULL /*our_lsa*/, peer_lsa,
- local_file, remote_file
- IF_FEATURE_TFTP_BLOCKSIZE(, 1 /* want_transfer_size */)
- IF_FEATURE_TFTP_BLOCKSIZE(, blksize)
- );
- tftp_progress_done();
- if (result != EXIT_SUCCESS && NOT_LONE_DASH(local_file) && CMD_GET(opt)) {
- unlink(local_file);
- }
- return result;
- }
- #endif /* ENABLE_TFTP */
- #if ENABLE_TFTPD
- int tftpd_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE;
- int tftpd_main(int argc UNUSED_PARAM, char **argv)
- {
- len_and_sockaddr *our_lsa;
- len_and_sockaddr *peer_lsa;
- char *mode, *user_opt;
- char *local_file = local_file;
- const char *error_msg;
- int opt, result, opcode;
- IF_FEATURE_TFTP_BLOCKSIZE(int blksize = TFTP_BLKSIZE_DEFAULT;)
- IF_FEATURE_TFTP_BLOCKSIZE(int want_transfer_size = 0;)
- INIT_G();
- our_lsa = get_sock_lsa(STDIN_FILENO);
- if (!our_lsa) {
- /* This is confusing:
- *bb_error_msg_and_die("stdin is not a socket");
- * Better: */
- bb_show_usage();
- /* Help text says that tftpd must be used as inetd service,
- * which is by far the most usual cause of get_sock_lsa
- * failure */
- }
- peer_lsa = xzalloc(LSA_LEN_SIZE + our_lsa->len);
- peer_lsa->len = our_lsa->len;
- /* Shifting to not collide with TFTP_OPTs */
- opt = option_mask32 = TFTPD_OPT | (getopt32(argv, "rcu:l", &user_opt) << 8);
- argv += optind;
- if (opt & TFTPD_OPT_l) {
- openlog(applet_name, LOG_PID, LOG_DAEMON);
- logmode = LOGMODE_SYSLOG;
- }
- if (opt & TFTPD_OPT_u) {
- /* Must be before xchroot */
- G.pw = xgetpwnam(user_opt);
- }
- if (argv[0]) {
- xchroot(argv[0]);
- }
- result = recv_from_to(STDIN_FILENO,
- G.block_buf, sizeof(G.block_buf) + 1,
- /* ^^^ sizeof+1 to reliably detect oversized input */
- 0 /* flags */,
- &peer_lsa->u.sa, &our_lsa->u.sa, our_lsa->len);
- error_msg = "malformed packet";
- opcode = ntohs(*(uint16_t*)G.block_buf);
- if (result < 4 || result > sizeof(G.block_buf)
- /*|| G.block_buf[result-1] != '\0' - bug compatibility, see below */
- || (IF_FEATURE_TFTP_PUT(opcode != TFTP_RRQ) /* not download */
- IF_GETPUT(&&)
- IF_FEATURE_TFTP_GET(opcode != TFTP_WRQ) /* not upload */
- )
- ) {
- goto err;
- }
- /* Some HP PA-RISC firmware always sends fixed 516-byte requests,
- * with trailing garbage.
- * Support that by not requiring NUL to be the last byte (see above).
- * To make strXYZ() ops safe, force NUL termination:
- */
- G.block_buf_tail[0] = '\0';
- local_file = G.block_buf + 2;
- if (local_file[0] == '.' || strstr(local_file, "/.")) {
- error_msg = "dot in file name";
- goto err;
- }
- mode = local_file + strlen(local_file) + 1;
- /* RFC 1350 says mode string is case independent */
- if (mode >= G.block_buf + result || strcasecmp(mode, "octet") != 0) {
- error_msg = "mode is not 'octet'";
- goto err;
- }
- # if ENABLE_FEATURE_TFTP_BLOCKSIZE
- {
- char *res;
- char *opt_str = mode + sizeof("octet");
- int opt_len = G.block_buf + result - opt_str;
- if (opt_len > 0) {
- res = tftp_get_option("blksize", opt_str, opt_len);
- if (res) {
- blksize = tftp_blksize_check(res, 65564);
- if (blksize < 0) {
- G_error_pkt_reason = ERR_BAD_OPT;
- /* will just send error pkt */
- goto do_proto;
- }
- }
- if (opcode != TFTP_WRQ /* download? */
- /* did client ask us about file size? */
- && tftp_get_option("tsize", opt_str, opt_len)
- ) {
- want_transfer_size = 1;
- }
- }
- }
- # endif
- if (!ENABLE_FEATURE_TFTP_PUT || opcode == TFTP_WRQ) {
- if (opt & TFTPD_OPT_r) {
- /* This would mean "disk full" - not true */
- /*G_error_pkt_reason = ERR_WRITE;*/
- error_msg = bb_msg_write_error;
- goto err;
- }
- IF_GETPUT(option_mask32 |= TFTP_OPT_GET;) /* will receive file's data */
- } else {
- IF_GETPUT(option_mask32 |= TFTP_OPT_PUT;) /* will send file's data */
- }
- /* NB: if G_error_pkt_str or G_error_pkt_reason is set up,
- * tftp_protocol() just sends one error pkt and returns */
- do_proto:
- close(STDIN_FILENO); /* close old, possibly wildcard socket */
- /* tftp_protocol() will create new one, bound to particular local IP */
- result = tftp_protocol(
- our_lsa, peer_lsa,
- local_file
- IF_TFTP(, NULL /*remote_file*/)
- IF_FEATURE_TFTP_BLOCKSIZE(, want_transfer_size)
- IF_FEATURE_TFTP_BLOCKSIZE(, blksize)
- );
- return result;
- err:
- strcpy(G_error_pkt_str, error_msg);
- goto do_proto;
- }
- #endif /* ENABLE_TFTPD */
- #endif /* ENABLE_FEATURE_TFTP_GET || ENABLE_FEATURE_TFTP_PUT */
|