tftpd: support full 512-byte requests

Some HP PA-RISC firmware always sends fixed 512-byte requests,
with trailing garbage.

function                                             old     new   delta
tftpd_main                                           578     572      -6

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko 2014-09-03 18:35:38 +02:00
parent f02c52bcde
commit 67e01fecce

View File

@ -119,6 +119,7 @@ struct globals {
struct passwd *pw;
/* used in tftpd_main(), a bit big for stack: */
char block_buf[TFTP_BLKSIZE_DEFAULT];
char block_buf_tail[1];
#if ENABLE_FEATURE_TFTP_PROGRESS_BAR
off_t pos;
off_t size;
@ -793,14 +794,16 @@ int tftpd_main(int argc UNUSED_PARAM, char **argv)
xchroot(argv[0]);
}
result = recv_from_to(STDIN_FILENO, G.block_buf, sizeof(G.block_buf),
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'
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 */
@ -808,6 +811,13 @@ int tftpd_main(int argc UNUSED_PARAM, char **argv)
) {
goto err;
}
/* Some HP PA-RISC firmware always sends fixed 512-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";