/* vi: set sw=4 ts=4: */
-/* -------------------------------------------------------------------------
- * 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>
*
- * Licensed under GPLv2 or later, see file LICENSE in this tarball for details.
- * ------------------------------------------------------------------------- */
-
-#include "busybox.h"
-
-
-#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 */
-
-static const char * const MODE_OCTET = "octet";
-#define MODE_OCTET_LEN 6 /* sizeof(MODE_OCTET)*/
-
-static const char * const OPTION_BLOCKSIZE = "blksize";
-#define OPTION_BLOCKSIZE_LEN 8 /* sizeof(OPTION_BLOCKSIZE) */
+ * tftpd added by Denys Vlasenko & Vladimir Dronnikov
+ *
+ * Licensed under GPLv2 or later, see file LICENSE in this source tree.
+ */
+
+//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: )
+//usage:
+//usage:#define tftpd_trivial_usage
+//usage: "[-cr] [-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 <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_ERROR 5
#define TFTP_OACK 6
-static const char *const tftp_bb_error_msg[] = {
- "Undefined error",
- "File not found",
- "Access violation",
- "Disk full or allocation error",
- "Illegal TFTP operation",
- "Unknown transfer ID",
- "File already exists",
- "No such user"
+/* 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,
};
-#define tftp_cmd_get ENABLE_FEATURE_TFTP_GET
-
-#if ENABLE_FEATURE_TFTP_PUT
-# define tftp_cmd_put (tftp_cmd_get+ENABLE_FEATURE_TFTP_PUT)
+#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 tftp_cmd_put 0
+#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(), a bit big for stack: */
+ char block_buf[TFTP_BLKSIZE_DEFAULT];
+#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)
+struct BUG_G_too_big {
+ char BUG_G_too_big[sizeof(G) <= COMMON_BUFSIZE ? 1 : -1];
+};
+#define INIT_G() do { } while (0)
+#define G_error_pkt_reason (G.error_pkt[3])
+#define G_error_pkt_str ((char*)(G.error_pkt + 4))
-#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
+#if ENABLE_FEATURE_TFTP_PROGRESS_BAR
+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_init() ((void)0)
+# define tftp_progress_done() ((void)0)
+#endif
-static int tftp_blocksize_check(int blocksize, int bufsize)
+#if ENABLE_FEATURE_TFTP_BLOCKSIZE
+
+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)) {
- bb_error_msg("bad blocksize");
- return 0;
+ * 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;
}
-
- 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 * const option)
+static char *tftp_get_option(const char *option, char *buf, int len)
{
int opt_val = 0;
int opt_found = 0;
int k;
- while (len > 0) {
-
- /* Make sure the options are terminated correctly */
+ /* 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') {
- break;
+ goto nul_found;
}
}
-
- if (k >= len) {
- break;
- }
-
- if (opt_val == 0) {
+ 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;
- }
+ } else if (opt_found) {
+ return buf;
}
k++;
-
buf += k;
len -= k;
-
opt_val ^= 1;
}
#endif
-static int tftp(const int cmd, const struct hostent *host,
- const char *remotefile, const int localfd,
- const unsigned short port, int tftp_bufsize)
+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))
{
- struct sockaddr_in sa;
- struct sockaddr_in from;
- struct timeval tv;
- socklen_t fromlen;
- fd_set rfds;
- int socketfd;
+#if !ENABLE_FEATURE_TFTP_BLOCKSIZE
+ enum { blksize = TFTP_BLKSIZE_DEFAULT };
+#endif
+
+ struct pollfd pfd[1];
+#define socket_fd (pfd[0].fd)
int len;
- int opcode = 0;
- int finished = 0;
- int timeout = TFTP_NUM_RETRIES;
- unsigned short block_nr = 1;
- unsigned short tmp;
+ 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;
-
- USE_FEATURE_TFTP_BLOCKSIZE(int want_option_ack = 0;)
-
/* Can't use RESERVE_CONFIG_BUFFER here since the allocation
- * size varies meaning BUFFERS_GO_ON_STACK would fail */
- char *buf=xmalloc(tftp_bufsize += 4);
-
- if ((socketfd = socket(PF_INET, SOCK_DGRAM, 0)) < 0) {
- /* need to unlink the localfile, so don't use xsocket here. */
- bb_perror_msg("socket");
- return EXIT_FAILURE;
+ * 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 */
+ }
}
- len = sizeof(sa);
-
- memset(&sa, 0, len);
- xbind(socketfd, (struct sockaddr *)&sa, len);
+ /* 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
+ }
- sa.sin_family = host->h_addrtype;
- sa.sin_port = port;
- memcpy(&sa.sin_addr, (struct in_addr *) host->h_addr,
- sizeof(sa.sin_addr));
+ /* 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;
+ }
- /* build opcode */
- if (cmd & tftp_cmd_get) {
- opcode = TFTP_RRQ;
- }
- if (cmd & tftp_cmd_put) {
+ } 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) {
-
- cp = buf;
-
- /* first create the opcode part */
- *((unsigned short *) cp) = htons(opcode);
+ /* Build ACK or DATA */
+ cp = xbuf + 2;
+ *((uint16_t*)cp) = htons(block_nr);
cp += 2;
-
- /* add filename and mode */
- if (((cmd & tftp_cmd_get) && (opcode == TFTP_RRQ)) ||
- ((cmd & tftp_cmd_put) && (opcode == TFTP_WRQ)))
- {
- int too_long = 0;
-
- /* see if the filename fits into buf
- * and fill in packet. */
- len = strlen(remotefile) + 1;
-
- if ((cp + len) >= &buf[tftp_bufsize - 1]) {
- too_long = 1;
- } else {
- safe_strncpy(cp, remotefile, len);
- cp += len;
- }
-
- if (too_long || ((&buf[tftp_bufsize - 1] - cp) < MODE_OCTET_LEN)) {
- bb_error_msg("remote filename too long");
- break;
- }
-
- /* add "mode" part of the package */
- memcpy(cp, MODE_OCTET, MODE_OCTET_LEN);
- cp += MODE_OCTET_LEN;
-
-#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
-
- len = tftp_bufsize - 4; /* data block size */
-
- if (len != TFTP_BLOCKSIZE_DEFAULT) {
-
- if ((&buf[tftp_bufsize - 1] - cp) < 15) {
- bb_error_msg("remote filename too long");
- break;
- }
-
- /* add "blksize" + number of blocks */
- memcpy(cp, OPTION_BLOCKSIZE, OPTION_BLOCKSIZE_LEN);
- cp += OPTION_BLOCKSIZE_LEN;
- cp += snprintf(cp, 6, "%d", len) + 1;
-
- want_option_ack = 1;
+ 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;
}
-#endif
- }
-
- /* add ack and data */
-
- if (((cmd & tftp_cmd_get) && (opcode == TFTP_ACK)) ||
- ((cmd & tftp_cmd_put) && (opcode == TFTP_DATA))) {
-
- *((unsigned short *) cp) = htons(block_nr);
-
- cp += 2;
-
- block_nr++;
-
- if ((cmd & tftp_cmd_put) && (opcode == TFTP_DATA)) {
- len = full_read(localfd, cp, tftp_bufsize - 4);
-
- if (len < 0) {
- bb_perror_msg(bb_msg_read_error);
- break;
- }
-
- if (len != (tftp_bufsize - 4)) {
- finished++;
- }
-
- cp += len;
+ 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);
-
- /* send packet */
-
-
- timeout = TFTP_NUM_RETRIES; /* re-initialize */
- do {
-
- len = cp - buf;
-
-#ifdef CONFIG_DEBUG_TFTP
- fprintf(stderr, "sending %u bytes\n", len);
- for (cp = buf; cp < &buf[len]; cp++)
- fprintf(stderr, "%02x ", (unsigned char) *cp);
- fprintf(stderr, "\n");
+#if ENABLE_FEATURE_TFTP_PROGRESS_BAR
+ if (is_bb_progress_inited(&G.pmt))
+ tftp_progress_update();
#endif
- if (sendto(socketfd, buf, len, 0,
- (struct sockaddr *) &sa, sizeof(sa)) < 0) {
- bb_perror_msg("send");
- len = -1;
- break;
+ /* 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 */
}
-
- if (finished && (opcode == TFTP_ACK)) {
- break;
+ /* exponential backoff with limit */
+ waittime_ms += waittime_ms/2;
+ if (waittime_ms > TFTP_MAXTIMEOUT_MS) {
+ waittime_ms = TFTP_MAXTIMEOUT_MS;
}
- /* receive packet */
-
- memset(&from, 0, sizeof(from));
- fromlen = sizeof(from);
-
- tv.tv_sec = TFTP_TIMEOUT;
- tv.tv_usec = 0;
-
- FD_ZERO(&rfds);
- FD_SET(socketfd, &rfds);
-
- switch (select(socketfd + 1, &rfds, NULL, NULL, &tv)) {
- case 1:
- len = recvfrom(socketfd, buf, tftp_bufsize, 0,
- (struct sockaddr *) &from, &fromlen);
-
- if (len < 0) {
- bb_perror_msg("recvfrom");
- break;
- }
-
- timeout = 0;
-
- if (sa.sin_port == port) {
- sa.sin_port = from.sin_port;
- }
- if (sa.sin_port == from.sin_port) {
- break;
- }
-
- /* fall-through for bad packets! */
- /* discard the packet - treat as timeout */
- timeout = TFTP_NUM_RETRIES;
- case 0:
- bb_error_msg("timeout");
-
- timeout--;
- if (timeout == 0) {
- len = -1;
- bb_error_msg("last timeout");
- }
- break;
- default:
- bb_perror_msg("select");
- len = -1;
+ 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;
}
-
- } while (timeout && (len >= 0));
-
- if ((finished) || (len < 0)) {
- break;
}
- /* process received packet */
-
- opcode = ntohs(*((unsigned short *) buf));
- tmp = ntohs(*((unsigned short *) &buf[2]));
-
-#ifdef CONFIG_DEBUG_TFTP
- fprintf(stderr, "received %d bytes: %04x %04x\n", len, opcode, tmp);
+ /* 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) {
- const char *msg = NULL;
-
- if (buf[4] != '\0') {
- msg = &buf[4];
- buf[tftp_bufsize - 1] = '\0';
- } else if (tmp < (sizeof(tftp_bb_error_msg)
- / sizeof(char *))) {
-
- msg = tftp_bb_error_msg[tmp];
+ 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);
}
-
- if (msg) {
- bb_error_msg("server says: %s", msg);
- }
-
- break;
+ bb_error_msg("server error: (%u) %s", recv_blk, msg);
+ goto ret;
}
-#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
- if (want_option_ack) {
-
- want_option_ack = 0;
+#if ENABLE_FEATURE_TFTP_BLOCKSIZE
+ if (expect_OACK) {
+ expect_OACK = 0;
if (opcode == TFTP_OACK) {
-
/* server seems to support options */
-
char *res;
- res = tftp_option_get(&buf[2], len - 2, OPTION_BLOCKSIZE);
-
+ res = tftp_get_option("blksize", &rbuf[2], len - 2);
if (res) {
- int blksize = atoi(res);
-
- if (tftp_blocksize_check(blksize, tftp_bufsize - 4)) {
-
- if (cmd & tftp_cmd_put) {
- opcode = TFTP_DATA;
- } else {
- opcode = TFTP_ACK;
- }
-#ifdef CONFIG_DEBUG_TFTP
- fprintf(stderr, "using %s %u\n", OPTION_BLOCKSIZE,
- blksize);
-#endif
- tftp_bufsize = blksize + 4;
- block_nr = 0;
- continue;
+ 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();
}
}
- /* FIXME:
- * we should send ERROR 8 */
- bb_error_msg("bad server option");
- break;
+# endif
+ if (CMD_GET(option_mask32)) {
+ /* We'll send ACK for OACK,
+ * such ACK has "block no" of 0 */
+ block_nr = 0;
+ }
+ continue;
}
-
- bb_error_msg("warning: blksize not supported by server"
- " - reverting to 512");
-
- tftp_bufsize = TFTP_BLOCKSIZE_DEFAULT + 4;
+ /* 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
-
- if ((cmd & tftp_cmd_get) && (opcode == TFTP_DATA)) {
-
- if (tmp == block_nr) {
-
- len = full_write(localfd, &buf[4], len - 4);
-
- if (len < 0) {
- bb_perror_msg(bb_msg_write_error);
- break;
+ /* 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 (len != (tftp_bufsize - 4)) {
- finished++;
+ if (sz != blksize) {
+ finished = 1;
}
-
- opcode = TFTP_ACK;
- continue;
+ IF_FEATURE_TFTP_PROGRESS_BAR(G.pos += sz;)
+ continue; /* send ACK */
}
- /* in case the last ack disappeared into the ether */
- if (tmp == (block_nr - 1)) {
- --block_nr;
- opcode = TFTP_ACK;
- continue;
- } else if (tmp + 1 == block_nr) {
+/* 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 = tmp;
- opcode = TFTP_ACK;
+ block_nr = recv_blk;
continue;
}
+#endif
}
- if ((cmd & tftp_cmd_put) && (opcode == TFTP_ACK)) {
-
- if (tmp == (unsigned short) (block_nr - 1)) {
- if (finished) {
- break;
- }
-
- opcode = TFTP_DATA;
- continue;
+ 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);
}
-
-#ifdef CONFIG_FEATURE_CLEAN_UP
- close(socketfd);
- free(buf);
-#endif
-
- return finished ? EXIT_SUCCESS : EXIT_FAILURE;
+ 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
}
-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)
{
- struct hostent *host = NULL;
- const char *localfile = NULL;
- const char *remotefile = NULL;
- int port;
- int cmd = 0;
- int fd = -1;
- int flags = 0;
+ 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 blocksize = TFTP_BLOCKSIZE_DEFAULT;
-
- /* figure out what to pass to getopt */
-
-#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
- char *sblocksize = NULL;
-
-#define BS "b:"
-#define BS_ARG , &sblocksize
-#else
-#define BS
-#define BS_ARG
-#endif
+ int port;
+ IF_GETPUT(int opt;)
+
+ INIT_G();
+
+ /* -p or -g is mandatory, and they are mutually exclusive */
+ opt_complementary = "" IF_FEATURE_TFTP_GET("g:") IF_FEATURE_TFTP_PUT("p:")
+ IF_GETPUT("g--p:p--g:");
+
+ IF_GETPUT(opt =) getopt32(argv,
+ IF_FEATURE_TFTP_GET("g") IF_FEATURE_TFTP_PUT("p")
+ "l:r:" IF_FEATURE_TFTP_BLOCKSIZE("b:"),
+ &local_file, &remote_file
+ IF_FEATURE_TFTP_BLOCKSIZE(, &blksize_str));
+ 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
-#ifdef CONFIG_FEATURE_TFTP_GET
-#define GET "g"
-#define GET_COMPL ":g"
-#else
-#define GET
-#define GET_COMPL
-#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;
+ }
-#ifdef CONFIG_FEATURE_TFTP_PUT
-#define PUT "p"
-#define PUT_COMPL ":p"
-#else
-#define PUT
-#define PUT_COMPL
-#endif
+ /* Error if filename or host is not known */
+ if (!remote_file || !argv[0])
+ bb_show_usage();
-#if defined(CONFIG_FEATURE_TFTP_GET) && defined(CONFIG_FEATURE_TFTP_PUT)
- opt_complementary = GET_COMPL PUT_COMPL ":?g--p:p--g";
-#elif defined(CONFIG_FEATURE_TFTP_GET) || defined(CONFIG_FEATURE_TFTP_PUT)
- opt_complementary = GET_COMPL PUT_COMPL;
-#endif
+ 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;
+}
- cmd = getopt32(argc, argv, GET PUT "l:r:" BS, &localfile, &remotefile BS_ARG);
+#endif /* ENABLE_TFTP */
- cmd &= (tftp_cmd_get | tftp_cmd_put);
-#ifdef CONFIG_FEATURE_TFTP_GET
- if (cmd == tftp_cmd_get)
- flags = O_WRONLY | O_CREAT | O_TRUNC;
-#endif
-#ifdef CONFIG_FEATURE_TFTP_PUT
- if (cmd == tftp_cmd_put)
- flags = O_RDONLY;
-#endif
+#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, *user_opt;
+ 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]);
+ }
-#ifdef CONFIG_FEATURE_TFTP_BLOCKSIZE
- if (sblocksize) {
- blocksize = atoi(sblocksize);
- if (!tftp_blocksize_check(blocksize, 0)) {
- return EXIT_FAILURE;
+ result = recv_from_to(STDIN_FILENO, G.block_buf, sizeof(G.block_buf),
+ 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'
+ || (IF_FEATURE_TFTP_PUT(opcode != TFTP_RRQ) /* not download */
+ IF_GETPUT(&&)
+ IF_FEATURE_TFTP_GET(opcode != TFTP_WRQ) /* not upload */
+ )
+ ) {
+ goto err;
+ }
+ 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) {
+ 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 (localfile == NULL)
- localfile = remotefile;
- if (remotefile == NULL)
- remotefile = localfile;
- if ((localfile == NULL && remotefile == NULL) || (argv[optind] == NULL))
- bb_show_usage();
-
- if (localfile == NULL || strcmp(localfile, "-") == 0) {
- fd = (cmd == tftp_cmd_get) ? STDOUT_FILENO : STDIN_FILENO;
+# 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 {
- fd = open(localfile, flags, 0644); /* fail below */
+ IF_GETPUT(option_mask32 |= TFTP_OPT_PUT;) /* will send file's data */
}
- if (fd < 0) {
- bb_perror_msg_and_die("local file");
- }
-
- host = xgethostbyname(argv[optind]);
- port = bb_lookup_port(argv[optind + 1], "udp", 69);
-#ifdef CONFIG_DEBUG_TFTP
- fprintf(stderr, "using server \"%s\", remotefile \"%s\", "
- "localfile \"%s\".\n",
- inet_ntoa(*((struct in_addr *) host->h_addr)),
- remotefile, localfile);
-#endif
+ /* NB: if G_error_pkt_str or G_error_pkt_reason is set up,
+ * tftp_protocol() just sends one error pkt and returns */
- result = tftp(cmd, host, remotefile, fd, port, blocksize);
+ 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)
+ );
- if (!(fd == STDOUT_FILENO || fd == STDIN_FILENO)) {
- if (ENABLE_FEATURE_CLEAN_UP)
- close(fd);
- if (cmd == tftp_cmd_get && result != EXIT_SUCCESS)
- unlink(localfile);
- }
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 */