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-rw-r--r--networking/tftp.c293
1 files changed, 242 insertions, 51 deletions
diff --git a/networking/tftp.c b/networking/tftp.c
index 999b5d7..530b3d1 100644
--- a/networking/tftp.c
+++ b/networking/tftp.c
@@ -3,7 +3,8 @@
/* */
/* A simple tftp client for busybox. */
/* Tries to follow RFC1350. */
-/* Only "octet" mode and 512-byte data blocks are supported. */
+/* Only "octet" mode supported. */
+/* Optional blocksize negotiation (RFC2347 + RFC2348) */
/* */
/* Copyright (C) 2001 Magnus Damm <damm@opensource.se> */
/* */
@@ -47,6 +48,18 @@
//#define BB_FEATURE_TFTP_DEBUG
+#define TFTP_BLOCKSIZE_DEFAULT 512 /* according to RFC 1350, don't change */
+#define TFTP_TIMEOUT 5 /* seconds */
+
+/* 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
+
static const char *tftp_error_msg[] = {
"Undefined error",
"File not found",
@@ -61,8 +74,71 @@ static const char *tftp_error_msg[] = {
const int tftp_cmd_get = 1;
const int tftp_cmd_put = 2;
+#ifdef BB_FEATURE_TFTP_BLOCKSIZE
+
+static int tftp_blocksize_check(int blocksize, int bufsize)
+{
+ /* Check if the blocksize 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 > 65464)) {
+ error_msg("bad blocksize");
+ return 0;
+ }
+
+ return blocksize;
+}
+
+static char *tftp_option_get(char *buf, int len, char *option)
+{
+ int opt_val = 0;
+ int opt_found = 0;
+ int k;
+
+ while (len > 0) {
+
+ /* Make sure the options are terminated correctly */
+
+ for (k = 0; k < len; k++) {
+ if (buf[k] == '\0') {
+ break;
+ }
+ }
+
+ if (k >= len) {
+ break;
+ }
+
+ if (opt_val == 0) {
+ 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 inline int tftp(const int cmd, const struct hostent *host,
- const char *serverfile, int localfd, const int port, int tftp_bufsize)
+ const char *remotefile, int localfd, const int port, int tftp_bufsize)
{
const int cmd_get = cmd & tftp_cmd_get;
const int cmd_put = cmd & tftp_cmd_put;
@@ -81,7 +157,12 @@ static inline int tftp(const int cmd, const struct hostent *host,
int finished = 0;
int timeout = bb_tftp_num_retries;
int block_nr = 1;
- RESERVE_BB_BUFFER(buf, tftp_bufsize + 4); // Why 4 ?
+
+#ifdef BB_FEATURE_TFTP_BLOCKSIZE
+ int want_option_ack = 0;
+#endif
+
+ RESERVE_BB_BUFFER(buf, tftp_bufsize + 4); /* Opcode + Block # + Data */
tftp_bufsize += 4;
@@ -103,50 +184,79 @@ static inline int tftp(const int cmd, const struct hostent *host,
/* build opcode */
if (cmd_get) {
- opcode = 1; // read request = 1
+ opcode = TFTP_RRQ;
}
if (cmd_put) {
- opcode = 2; // write request = 2
+ opcode = TFTP_WRQ;
}
while (1) {
-
- /* build packet of type "opcode" */
-
-
cp = buf;
+ /* first create the opcode part */
+
*((unsigned short *) cp) = htons(opcode);
cp += 2;
/* add filename and mode */
- if ((cmd_get && (opcode == 1)) || // read request = 1
- (cmd_put && (opcode == 2))) { // write request = 2
+ if ((cmd_get && (opcode == TFTP_RRQ)) ||
+ (cmd_put && (opcode == TFTP_WRQ))) {
+ int too_long = 0;
- /* what is this trying to do ? */
- while (cp != &buf[tftp_bufsize - 1]) {
- if ((*cp = *serverfile++) == '\0')
- break;
- cp++;
+ /* 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;
}
- /* and this ? */
- if ((*cp != '\0') || (&buf[tftp_bufsize - 1] - cp) < 7) {
- error_msg("too long server-filename");
+ else {
+ safe_strncpy(cp, remotefile, len);
+ cp += len;
+ }
+
+ if (too_long || ((&buf[tftp_bufsize - 1] - cp) < 6)) {
+ error_msg("too long remote-filename");
break;
}
- memcpy(cp + 1, "octet", 6);
- cp += 7;
+ /* add "mode" part of the package */
+
+ memcpy(cp, "octet", 6);
+ cp += 6;
+
+#ifdef BB_FEATURE_TFTP_BLOCKSIZE
+
+ len = tftp_bufsize - 4; /* data block size */
+
+ if (len != TFTP_BLOCKSIZE_DEFAULT) {
+
+ if ((&buf[tftp_bufsize - 1] - cp) < 15) {
+ error_msg("too long remote-filename");
+ break;
+ }
+
+ /* add "blksize" + number of blocks */
+
+ memcpy(cp, "blksize", 8);
+ cp += 8;
+
+ cp += snprintf(cp, 6, "%d", len) + 1;
+
+ want_option_ack = 1;
+ }
+#endif
}
/* add ack and data */
- if ((cmd_get && (opcode == 4)) || // acknowledgement = 4
- (cmd_put && (opcode == 3))) { // data packet == 3
+ if ((cmd_get && (opcode == TFTP_ACK)) ||
+ (cmd_put && (opcode == TFTP_DATA))) {
*((unsigned short *) cp) = htons(block_nr);
@@ -154,7 +264,7 @@ static inline int tftp(const int cmd, const struct hostent *host,
block_nr++;
- if (cmd_put && (opcode == 3)) { // data packet == 3
+ if (cmd_put && (opcode == TFTP_DATA)) {
len = read(localfd, cp, tftp_bufsize - 4);
if (len < 0) {
@@ -200,7 +310,7 @@ static inline int tftp(const int cmd, const struct hostent *host,
memset(&from, 0, sizeof(from));
fromlen = sizeof(from);
- tv.tv_sec = 5; // BB_TFPT_TIMEOUT = 5
+ tv.tv_sec = TFTP_TIMEOUT;
tv.tv_usec = 0;
FD_ZERO(&rfds);
@@ -261,9 +371,76 @@ static inline int tftp(const int cmd, const struct hostent *host,
printf("received %d bytes: %04x %04x\n", len, opcode, tmp);
#endif
- if (cmd_get && (opcode == 3)) { // data packet == 3
+ if (opcode == TFTP_ERROR) {
+ char *msg = NULL;
+
+ if (buf[4] != '\0') {
+ msg = &buf[4];
+ buf[tftp_bufsize - 1] = '\0';
+ } else if (tmp < (sizeof(tftp_error_msg)
+ / sizeof(char *))) {
+
+ msg = (char *) tftp_error_msg[tmp];
+ }
+
+ if (msg) {
+ error_msg("server says: %s", msg);
+ }
+
+ break;
+ }
+
+#ifdef BB_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(&buf[2], len-2,
+ "blksize");
+
+ if (res) {
+ int foo = atoi(res);
+
+ if (tftp_blocksize_check(foo,
+ tftp_bufsize - 4)) {
+
+ if (cmd_put) {
+ opcode = TFTP_DATA;
+ }
+ else {
+ opcode = TFTP_ACK;
+ }
+#ifdef BB_FEATURE_TFTP_DEBUG
+ printf("using blksize %u\n");
+#endif
+ tftp_bufsize = foo + 4;
+ block_nr = 0;
+ continue;
+ }
+ }
+ /* FIXME:
+ * we should send ERROR 8 */
+ error_msg("bad server option");
+ break;
+ }
+
+ error_msg("warning: blksize not supported by server"
+ " - reverting to 512");
+
+ tftp_bufsize = TFTP_BLOCKSIZE_DEFAULT + 4;
+ }
+#endif
+
+ if (cmd_get && (opcode == TFTP_DATA)) {
if (tmp == block_nr) {
+
len = write(localfd, &buf[4], len - 4);
if (len < 0) {
@@ -275,43 +452,30 @@ static inline int tftp(const int cmd, const struct hostent *host,
finished++;
}
- opcode = 4; // acknowledgement = 4
+ opcode = TFTP_ACK;
continue;
}
}
- if (cmd_put && (opcode == 4)) { // acknowledgement = 4
+ if (cmd_put && (opcode == TFTP_ACK)) {
if (tmp == (block_nr - 1)) {
if (finished) {
break;
}
- opcode = 3; // data packet == 3
+ opcode = TFTP_DATA;
continue;
}
}
-
- if (opcode == 5) { // error code == 5
- char *msg = NULL;
-
- if (buf[4] != '\0') {
- msg = &buf[4];
- buf[tftp_bufsize - 1] = '\0';
- } else if (tmp < (sizeof(tftp_error_msg) / sizeof(char *))) {
- msg = (char *) tftp_error_msg[tmp];
- }
-
- if (msg) {
- error_msg("server says: %s", msg);
- }
-
- break;
- }
}
+#ifdef BB_FEATURE_CLEAN_UP
close(socketfd);
+ RELEASE_BB_BUFFER(buf);
+#endif
+
return finished ? EXIT_SUCCESS : EXIT_FAILURE;
}
@@ -326,13 +490,38 @@ int tftp_main(int argc, char **argv)
int flags = 0;
int opt;
int result;
- int blocksize = 512;
+ int blocksize = TFTP_BLOCKSIZE_DEFAULT;
+
+ /* figure out what to pass to getopt */
- while ((opt = getopt(argc, argv, "b:gpl:r:")) != -1) {
+#ifdef BB_FEATURE_TFTP_BLOCKSIZE
+#define BS "b:"
+#else
+#define BS
+#endif
+
+#ifdef BB_FEATURE_TFTP_GET
+#define GET "g"
+#else
+#define GET
+#endif
+
+#ifdef BB_FEATURE_TFTP_PUT
+#define PUT "p"
+#else
+#define PUT
+#endif
+
+ while ((opt = getopt(argc, argv, BS GET PUT "l:r:")) != -1) {
switch (opt) {
+#ifdef BB_FEATURE_TFTP_BLOCKSIZE
case 'b':
blocksize = atoi(optarg);
+ if (!tftp_blocksize_check(blocksize, 0)) {
+ return EXIT_FAILURE;
+ }
break;
+#endif
#ifdef BB_FEATURE_TFTP_GET
case 'g':
cmd = tftp_cmd_get;
@@ -370,14 +559,16 @@ int tftp_main(int argc, char **argv)
}
#ifdef BB_FEATURE_TFTP_DEBUG
- printf("using server \"%s\", serverfile \"%s\","
+ printf("using server \"%s\", remotefile \"%s\", "
"localfile \"%s\".\n",
inet_ntoa(*((struct in_addr *) host->h_addr)),
remotefile, localfile);
#endif
result = tftp(cmd, host, remotefile, fd, port, blocksize);
- close(fd);
+#ifdef BB_FEATURE_CLEAN_UP
+ close(fd);
+#endif
return(result);
-} \ No newline at end of file
+}
generated by cgit v1.1 at 2024-12-27 11:09:13 +0000