/* -------------------------------------------------------------------------
* tftp.c
*
- * A simple tftp client for busybox.
+ * A simple tftp client/server for busybox.
* Tries to follow RFC1350.
* Only "octet" mode supported.
* Optional blocksize negotiation (RFC2347 + RFC2348)
*
* 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 tarball for details.
* ------------------------------------------------------------------------- */
#include "libbb.h"
-
#if ENABLE_FEATURE_TFTP_GET || ENABLE_FEATURE_TFTP_PUT
-#define TFTP_BLOCKSIZE_DEFAULT 512 /* according to RFC 1350, don't change */
-#define TFTP_TIMEOUT 5 /* seconds */
-#define TFTP_NUM_RETRIES 5 /* number of retries */
+#define TFTP_BLKSIZE_DEFAULT 512 /* according to RFC 1350, don't change */
+#define TFTP_BLKSIZE_DEFAULT_STR "512"
+#define TFTP_TIMEOUT_MS 50
+#define TFTP_MAXTIMEOUT_MS 2000
+#define TFTP_NUM_RETRIES 12 /* number of backed-off retries */
/* opcodes we support */
#define TFTP_RRQ 1
#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,
+};
+
#if ENABLE_FEATURE_TFTP_GET && !ENABLE_FEATURE_TFTP_PUT
#define USE_GETPUT(...)
#define CMD_GET(cmd) 1
#define CMD_PUT(cmd) 1
#else
#define USE_GETPUT(...) __VA_ARGS__
-/* masks coming from getpot32 */
-#define CMD_GET(cmd) ((cmd) & 1)
-#define CMD_PUT(cmd) ((cmd) & 2)
+#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];
+ char *user_opt;
+ /* used in tftpd_main(), a bit big for stack: */
+ char block_buf[TFTP_BLKSIZE_DEFAULT];
+};
+#define G (*(struct globals*)&bb_common_bufsiz1)
+#define block_buf (G.block_buf )
+#define user_opt (G.user_opt )
+#define error_pkt (G.error_pkt )
+#define INIT_G() do { } while (0)
+
+#define error_pkt_reason (error_pkt[3])
+#define error_pkt_str (error_pkt + 4)
+
+
#if ENABLE_FEATURE_TFTP_BLOCKSIZE
-static int tftp_blocksize_check(int blocksize, int bufsize)
+static int tftp_blksize_check(const char *blksize_str, int maxsize)
{
- /* Check if the blocksize is valid:
+ /* Check if the blksize is valid:
* RFC2348 says between 8 and 65464,
* but our implementation makes it impossible
- * to use blocksizes smaller than 22 octets.
- */
-
- if ((bufsize && (blocksize > bufsize))
- || (blocksize < 8) || (blocksize > 65564)
+ * 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");
- return 0;
+ bb_error_msg("bad blocksize '%s'", blksize_str);
+ return -1;
}
-
- return blocksize;
+#if ENABLE_TFTP_DEBUG
+ bb_error_msg("using blksize %u", blksize);
+#endif
+ return blksize;
}
-static char *tftp_option_get(char *buf, int len, const char *option)
+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 the options are terminated correctly */
+ /* 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) {
+ if (opt_val == 0) { /* it's "name" part */
if (strcasecmp(buf, option) == 0) {
opt_found = 1;
}
#endif
-static int tftp( USE_GETPUT(const int cmd,)
+static int tftp_protocol(
+ len_and_sockaddr *our_lsa,
len_and_sockaddr *peer_lsa,
- const char *remotefile, const int localfd,
- unsigned port, int tftp_bufsize)
+ const char *local_file
+ USE_TFTP(, const char *remote_file)
+ USE_FEATURE_TFTP_BLOCKSIZE(USE_TFTPD(, void *tsize))
+ USE_FEATURE_TFTP_BLOCKSIZE(, int blksize))
{
- struct timeval tv;
- fd_set rfds;
- int socketfd;
+#if !ENABLE_TFTP
+#define remote_file NULL
+#endif
+#if !(ENABLE_FEATURE_TFTP_BLOCKSIZE && ENABLE_TFTPD)
+#define tsize NULL
+#endif
+#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;
USE_FEATURE_TFTP_BLOCKSIZE(smallint want_option_ack = 0;)
smallint finished = 0;
uint16_t opcode;
- uint16_t block_nr = 1;
+ uint16_t block_nr;
uint16_t recv_blk;
- int timeout = TFTP_NUM_RETRIES;
+ int open_mode, local_fd;
+ int retries, waittime_ms;
+ int io_bufsize = blksize + 4;
char *cp;
-
- unsigned org_port;
- len_and_sockaddr *const from = alloca(offsetof(len_and_sockaddr, sa) + peer_lsa->len);
-
/* 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 seperate */
/* In case we rcv a garbage pkt and we need to rexmit the last pkt */
- char *xbuf = xmalloc(tftp_bufsize += 4);
- char *rbuf = xmalloc(tftp_bufsize);
+ char *xbuf = xmalloc(io_bufsize);
+ char *rbuf = xmalloc(io_bufsize);
- port = org_port = htons(port);
+ socket_fd = xsocket(peer_lsa->u.sa.sa_family, SOCK_DGRAM, 0);
+ setsockopt_reuseaddr(socket_fd);
- socketfd = xsocket(peer_lsa->sa.sa_family, SOCK_DGRAM, 0);
+ block_nr = 1;
+ cp = xbuf + 2;
- /* build opcode */
- opcode = TFTP_WRQ;
- if (CMD_GET(cmd)) {
- opcode = TFTP_RRQ;
+ 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 (error_pkt_reason || error_pkt_str[0])
+ goto send_err_pkt;
+
+ if (CMD_GET(option_mask32)) {
+ /* it's upload - we must ACK 1st packet (with filename)
+ * as if it's "block 0" */
+ block_nr = 0;
+ }
+
+ if (user_opt) {
+ struct passwd *pw = xgetpwnam(user_opt);
+ change_identity(pw); /* initgroups, setgid, setuid */
+ }
}
- cp = xbuf + 2;
- /* add filename and mode */
- /* fill in packet if the filename fits into xbuf */
- len = strlen(remotefile) + 1;
- if (2 + len + sizeof("octet") >= tftp_bufsize) {
- bb_error_msg("remote filename is too long");
- goto ret;
+
+ /* Open local file (must be after changing user) */
+ 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
+ }
+ if (!(option_mask32 & TFTPD_OPT)) {
+ local_fd = CMD_GET(option_mask32) ? STDOUT_FILENO : STDIN_FILENO;
+ if (NOT_LONE_DASH(local_file))
+ local_fd = xopen(local_file, open_mode);
+ } else {
+ local_fd = open(local_file, open_mode);
+ if (local_fd < 0) {
+ error_pkt_reason = ERR_NOFILE;
+ strcpy((char*)error_pkt_str, "can't open file");
+ goto send_err_pkt;
+ }
}
- strcpy(cp, remotefile);
- cp += len;
- /* add "mode" part of the package */
- strcpy(cp, "octet");
- cp += sizeof("octet");
+ if (!ENABLE_TFTP || our_lsa) {
+/* gcc 4.3.1 would NOT optimize it out as it should! */
#if ENABLE_FEATURE_TFTP_BLOCKSIZE
- len = tftp_bufsize - 4; /* data block size */
- if (len != TFTP_BLOCKSIZE_DEFAULT) {
- /* rfc2348 says that 65464 is a max allowed value */
- if ((&xbuf[tftp_bufsize - 1] - cp) < sizeof("blksize NNNNN")) {
+ if (blksize != TFTP_BLKSIZE_DEFAULT || tsize) {
+ /* 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
+ } else {
+/* Removing it, 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 package */
+ strcpy(cp, "octet");
+ cp += sizeof("octet");
+
+#if ENABLE_FEATURE_TFTP_BLOCKSIZE
+ if (blksize == TFTP_BLKSIZE_DEFAULT)
+ goto send_pkt;
+
+ /* Non-standard blocksize: add option to pkt */
+ if ((&xbuf[io_bufsize - 1] - cp) < sizeof("blksize NNNNN")) {
bb_error_msg("remote filename is too long");
goto ret;
}
- /* add "blksize", <nul>, blocksize */
- strcpy(cp, "blksize");
- cp += sizeof("blksize");
- cp += snprintf(cp, 6, "%d", len) + 1;
want_option_ack = 1;
- }
#endif
- /* First packet is built, so skip packet generation */
- goto send_pkt;
+#endif /* ENABLE_TFTP */
+
+#if ENABLE_FEATURE_TFTP_BLOCKSIZE
+ add_blksize_opt:
+#if ENABLE_TFTPD
+ if (tsize) {
+ struct stat st;
+ /* add "tsize", <nul>, size, <nul> */
+ strcpy(cp, "tsize");
+ cp += sizeof("tsize");
+ fstat(local_fd, &st);
+ cp += snprintf(cp, 10, "%u", (int) st.st_size) + 1;
+ }
+#endif
+ if (blksize != TFTP_BLKSIZE_DEFAULT) {
+ /* add "blksize", <nul>, blksize, <nul> */
+ strcpy(cp, "blksize");
+ cp += sizeof("blksize");
+ cp += snprintf(cp, 6, "%d", blksize) + 1;
+ }
+#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;
cp += 2;
block_nr++;
opcode = TFTP_ACK;
- if (CMD_PUT(cmd)) {
+ if (CMD_PUT(option_mask32)) {
opcode = TFTP_DATA;
- len = full_read(localfd, cp, tftp_bufsize - 4);
+ len = full_read(local_fd, cp, blksize);
if (len < 0) {
- bb_perror_msg(bb_msg_read_error);
- goto ret;
+ goto send_read_err_pkt;
}
- if (len != (tftp_bufsize - 4)) {
+ if (len != blksize) {
finished = 1;
}
cp += len;
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_DEBUG_TFTP
+#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(socketfd, xbuf, send_len, &peer_lsa->sa, peer_lsa->len);
+ xsendto(socket_fd, xbuf, send_len, &peer_lsa->u.sa, peer_lsa->len);
/* Was it final ACK? then exit */
if (finished && (opcode == TFTP_ACK))
goto ret;
- timeout = TFTP_NUM_RETRIES; /* re-initialize */
recv_again:
/* Receive packet */
- tv.tv_sec = TFTP_TIMEOUT;
- tv.tv_usec = 0;
- FD_ZERO(&rfds);
- FD_SET(socketfd, &rfds);
- switch (select(socketfd + 1, &rfds, NULL, NULL, &tv)) {
- unsigned from_port;
+ /*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) {
+ 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:
- from->len = peer_lsa->len;
- memset(&from->sa, 0, peer_lsa->len);
- len = recvfrom(socketfd, rbuf, tftp_bufsize, 0,
- &from->sa, &from->len);
- if (len < 0) {
- bb_perror_msg("recvfrom");
- goto ret;
+ 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);
}
- from_port = get_nport(&from->sa);
- if (port == org_port) {
- /* Our first query went to port 69
- * but reply will come from different one.
- * Remember and use this new port */
- port = from_port;
- set_nport(peer_lsa, from_port);
+ if (len < 0) {
+ goto send_read_err_pkt;
}
- if (port != from_port)
+ if (len < 4) { /* too small? */
goto recv_again;
- goto process_pkt;
- case 0:
- timeout--;
- if (timeout == 0) {
- bb_error_msg("last timeout");
- goto ret;
}
- bb_error_msg("last timeout" + 5);
- goto send_again; /* resend last sent pkt */
- default:
- bb_perror_msg("select");
- goto ret;
}
- process_pkt:
+
/* Process recv'ed packet */
opcode = ntohs( ((uint16_t*)rbuf)[0] );
recv_blk = ntohs( ((uint16_t*)rbuf)[1] );
-
-#if ENABLE_DEBUG_TFTP
+#if ENABLE_TFTP_DEBUG
fprintf(stderr, "received %d bytes: %04x %04x\n", len, opcode, recv_blk);
#endif
-
if (opcode == TFTP_ERROR) {
- static const char *const errcode_str[] = {
- "",
- "file not found",
- "access violation",
- "disk full",
- "illegal TFTP operation",
- "unknown transfer id",
- "file already exists",
- "no such user",
- "bad option"
- };
+ 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 (rbuf[4] != '\0') {
+ if (len > 4 && rbuf[4] != '\0') {
msg = &rbuf[4];
- rbuf[tftp_bufsize - 1] = '\0';
- } else if (recv_blk < ARRAY_SIZE(errcode_str)) {
- msg = errcode_str[recv_blk];
+ 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 (want_option_ack) {
want_option_ack = 0;
-
if (opcode == TFTP_OACK) {
/* server seems to support options */
char *res;
- res = tftp_option_get(&rbuf[2], len - 2, "blksize");
+ res = tftp_get_option("blksize", &rbuf[2], len - 2);
if (res) {
- int blksize = xatoi_u(res);
- if (!tftp_blocksize_check(blksize, tftp_bufsize - 4)) {
- /* send ERROR 8 to server... */
- /* htons can be impossible to use in const initializer: */
- /*static const uint16_t error_8[2] = { htons(TFTP_ERROR), htons(8) };*/
- /* thus we open-code big-endian layout */
- static const uint8_t error_8[4] = { 0,TFTP_ERROR, 0,8 };
- xsendto(socketfd, error_8, 4, &peer_lsa->sa, peer_lsa->len);
- bb_error_msg("server proposes bad blksize %d, exiting", blksize);
- goto ret;
+ blksize = tftp_blksize_check(res, blksize);
+ if (blksize < 0) {
+ error_pkt_reason = ERR_BAD_OPT;
+ goto send_err_pkt;
}
-#if ENABLE_DEBUG_TFTP
- fprintf(stderr, "using blksize %u\n",
- blksize);
-#endif
- tftp_bufsize = blksize + 4;
+ io_bufsize = blksize + 4;
/* Send ACK for OACK ("block" no: 0) */
block_nr = 0;
continue;
* must be ignored by the client and server
* as if it were never requested." */
}
-
- bb_error_msg("blksize is not supported by server"
- " - reverting to 512");
- tftp_bufsize = TFTP_BLOCKSIZE_DEFAULT + 4;
+ bb_error_msg("server only supports blocksize of 512");
+ 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(cmd) && (opcode == TFTP_DATA)) {
+ if (CMD_GET(option_mask32) && (opcode == TFTP_DATA)) {
if (recv_blk == block_nr) {
- len = full_write(localfd, &rbuf[4], len - 4);
- if (len < 0) {
- bb_perror_msg(bb_msg_write_error);
- goto ret;
+ int sz = full_write(local_fd, &rbuf[4], len - 4);
+ if (sz != len - 4) {
+ strcpy((char*)error_pkt_str, bb_msg_write_error);
+ error_pkt_reason = ERR_WRITE;
+ goto send_err_pkt;
}
- if (len != (tftp_bufsize - 4)) {
+ if (sz != blksize) {
finished = 1;
}
continue; /* send ACK */
}
}
- if (CMD_PUT(cmd) && (opcode == TFTP_ACK)) {
- /* did server ACK our last DATA pkt? */
+ 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;
* See:
* http://en.wikipedia.org/wiki/Sorcerer's_Apprentice_Syndrome
*/
- }
+ } /* end of "while (1)" */
ret:
if (ENABLE_FEATURE_CLEAN_UP) {
- close(socketfd);
+ close(local_fd);
+ close(socket_fd);
free(xbuf);
free(rbuf);
}
return finished == 0; /* returns 1 on failure */
+
+ send_read_err_pkt:
+ strcpy((char*)error_pkt_str, bb_msg_read_error);
+ send_err_pkt:
+ if (error_pkt_str[0])
+ bb_error_msg((char*)error_pkt_str);
+ error_pkt[1] = TFTP_ERROR;
+ xsendto(socket_fd, error_pkt, 4 + 1 + strlen((char*)error_pkt_str),
+ &peer_lsa->u.sa, peer_lsa->len);
+ return EXIT_FAILURE;
+#undef remote_file
+#undef tsize
}
-int tftp_main(int argc, char **argv);
-int tftp_main(int argc, char **argv)
+#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 *localfile = NULL;
- const char *remotefile = NULL;
+ const char *local_file = NULL;
+ const char *remote_file = NULL;
#if ENABLE_FEATURE_TFTP_BLOCKSIZE
- const char *sblocksize = NULL;
+ const char *blksize_str = TFTP_BLKSIZE_DEFAULT_STR;
+ int blksize;
#endif
- int port;
- USE_GETPUT(int cmd;)
- int fd = -1;
- int flags = 0;
int result;
- int blocksize = TFTP_BLOCKSIZE_DEFAULT;
+ int port;
+ USE_GETPUT(int opt;)
+
+ INIT_G();
/* -p or -g is mandatory, and they are mutually exclusive */
opt_complementary = "" USE_FEATURE_TFTP_GET("g:") USE_FEATURE_TFTP_PUT("p:")
- USE_GETPUT("?g--p:p--g");
+ USE_GETPUT("g--p:p--g:");
- USE_GETPUT(cmd =) getopt32(argv,
+ USE_GETPUT(opt =) getopt32(argv,
USE_FEATURE_TFTP_GET("g") USE_FEATURE_TFTP_PUT("p")
"l:r:" USE_FEATURE_TFTP_BLOCKSIZE("b:"),
- &localfile, &remotefile
- USE_FEATURE_TFTP_BLOCKSIZE(, &sblocksize));
+ &local_file, &remote_file
+ USE_FEATURE_TFTP_BLOCKSIZE(, &blksize_str));
argv += optind;
- flags = O_RDONLY;
- if (CMD_GET(cmd))
- flags = O_WRONLY | O_CREAT | O_TRUNC;
-
#if ENABLE_FEATURE_TFTP_BLOCKSIZE
- if (sblocksize) {
- blocksize = xatoi_u(sblocksize);
- if (!tftp_blocksize_check(blocksize, 0)) {
- return EXIT_FAILURE;
- }
+ /* 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 (!localfile)
- localfile = remotefile;
- if (!remotefile)
- remotefile = localfile;
+ if (!local_file)
+ local_file = remote_file;
+ if (!remote_file)
+ remote_file = local_file;
/* Error if filename or host is not known */
- if (!remotefile || !argv[0])
+ if (!remote_file || !argv[0])
bb_show_usage();
- fd = CMD_GET(cmd) ? STDOUT_FILENO : STDIN_FILENO;
- if (!LONE_DASH(localfile)) {
- fd = xopen(localfile, flags);
- }
-
port = bb_lookup_port(argv[1], "udp", 69);
peer_lsa = xhost2sockaddr(argv[0], port);
-#if ENABLE_DEBUG_TFTP
- fprintf(stderr, "using server '%s', remotefile '%s', localfile '%s'\n",
- xmalloc_sockaddr2dotted(&peer_lsa->sa),
- remotefile, localfile);
+#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
- result = tftp( USE_GETPUT(cmd,) peer_lsa, remotefile, fd, port, blocksize);
+ result = tftp_protocol(
+ NULL /*our_lsa*/, peer_lsa,
+ local_file, remote_file
+ USE_FEATURE_TFTP_BLOCKSIZE(USE_TFTPD(, NULL /*tsize*/))
+ USE_FEATURE_TFTP_BLOCKSIZE(, blksize)
+ );
+
+ 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 *local_file, *mode;
+ const char *error_msg;
+ int opt, result, opcode;
+ USE_FEATURE_TFTP_BLOCKSIZE(int blksize = TFTP_BLKSIZE_DEFAULT;)
+ USE_FEATURE_TFTP_BLOCKSIZE(char *tsize = NULL;)
+
+ 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:", &user_opt) << 8);
+ argv += optind;
+ if (argv[0])
+ xchdir(argv[0]);
+
+ result = recv_from_to(STDIN_FILENO, block_buf, sizeof(block_buf),
+ 0 /* flags */,
+ &peer_lsa->u.sa, &our_lsa->u.sa, our_lsa->len);
+
+ error_msg = "malformed packet";
+ opcode = ntohs(*(uint16_t*)block_buf);
+ if (result < 4 || result >= sizeof(block_buf)
+ || block_buf[result-1] != '\0'
+ || (USE_FEATURE_TFTP_PUT(opcode != TFTP_RRQ) /* not download */
+ USE_GETPUT(&&)
+ USE_FEATURE_TFTP_GET(opcode != TFTP_WRQ) /* not upload */
+ )
+ ) {
+ goto err;
+ }
+ local_file = 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;
+ if (mode >= block_buf + result || strcmp(mode, "octet") != 0) {
+ goto err;
+ }
+#if ENABLE_FEATURE_TFTP_BLOCKSIZE
+ {
+ char *res;
+ char *opt_str = mode + sizeof("octet");
+ int opt_len = 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) {
+ error_pkt_reason = ERR_BAD_OPT;
+ /* will just send error pkt */
+ goto do_proto;
+ }
+ }
+ /* did client ask us about file size? */
+ tsize = tftp_get_option("tsize", opt_str, opt_len);
+ }
+ }
+#endif
- if (ENABLE_FEATURE_CLEAN_UP)
- close(fd);
- if (result != EXIT_SUCCESS && !LONE_DASH(localfile) && CMD_GET(cmd)) {
- unlink(localfile);
+ if (!ENABLE_FEATURE_TFTP_PUT || opcode == TFTP_WRQ) {
+ if (opt & TFTPD_OPT_r) {
+ /* This would mean "disk full" - not true */
+ /*error_pkt_reason = ERR_WRITE;*/
+ error_msg = bb_msg_write_error;
+ goto err;
+ }
+ USE_GETPUT(option_mask32 |= TFTP_OPT_GET;) /* will receive file's data */
+ } else {
+ USE_GETPUT(option_mask32 |= TFTP_OPT_PUT;) /* will send file's data */
}
+
+ /* NB: if error_pkt_str or 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 USE_TFTP(, NULL /*remote_file*/)
+ USE_FEATURE_TFTP_BLOCKSIZE(, tsize)
+ USE_FEATURE_TFTP_BLOCKSIZE(, blksize)
+ );
+
return result;
+ err:
+ strcpy((char*)error_pkt_str, error_msg);
+ goto do_proto;
}
+#endif /* ENABLE_TFTPD */
+
#endif /* ENABLE_FEATURE_TFTP_GET || ENABLE_FEATURE_TFTP_PUT */