emo/busybox
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity

wget: add EPSV support

Browse Source 
function                                             old     new   delta
parse_pasv_epsv                                        -     151    +151
wget_main                                           2440    2382     -58
xconnect_ftpdata                                     223      94    -129
------------------------------------------------------------------------------
(add/remove: 2/0 grow/shrink: 0/2 up/down: 151/-187)          Total: -36 bytes

Signed-off-by: Denys Vlasenko <vda.linux@googlemail.com>
This commit is contained in:
Denys Vlasenko
2018-02-06 15:48:12 +01:00
parent 403f2999f9
commit 1783ffa990
4 changed files with 82 additions and 61 deletions
Download Patch File Download Diff File Expand all files Collapse all files

57
networking/ftpgetput.c
View File

@ -152,57 +152,16 @@ static void ftp_login(void)
static int xconnect_ftpdata(void)
{
char *buf_ptr;
unsigned port_num;
int port_num;
/*
PASV command will not work for IPv6. RFC2428 describes
IPv6-capable "extended PASV" - EPSV.
"EPSV [protocol]" asks server to bind to and listen on a data port
in specified protocol. Protocol is 1 for IPv4, 2 for IPv6.
If not specified, defaults to "same as used for control connection".
If server understood you, it should answer "229 <some text>(|||port|)"
where "|" are literal pipe chars and "port" is ASCII decimal port#.
There is also an IPv6-capable replacement for PORT (EPRT),
but we don't need that.
NB: PASV may still work for some servers even over IPv6.
For example, vsftp happily answers
"227 Entering Passive Mode (0,0,0,0,n,n)" and proceeds as usual.
*/
if (!ENABLE_FEATURE_IPV6
|| ftpcmd("EPSV", NULL) != 229
) {
/* maybe also go straight to PAST if lsa->u.sa.sa_family == AF_INET? */
if (ftpcmd("PASV", NULL) != 227) {
ftp_die("PASV");
}
/* Response is "NNN garbageN1,N2,N3,N4,P1,P2[)garbage]"
* Server's IP is N1.N2.N3.N4 (we ignore it)
* Server's port for data connection is P1*256+P2 */
buf_ptr = strrchr(buf, ')');
if (buf_ptr) *buf_ptr = '\0';
buf_ptr = strrchr(buf, ',');
*buf_ptr = '\0';
port_num = xatoul_range(buf_ptr + 1, 0, 255);
buf_ptr = strrchr(buf, ',');
*buf_ptr = '\0';
port_num += xatoul_range(buf_ptr + 1, 0, 255) * 256;
} else {
/* Response is "NNN garbage(|||P1|)"
* Server's port for data connection is P1 */
buf_ptr = strrchr(buf, '|');
if (buf_ptr) *buf_ptr = '\0';
buf_ptr = strrchr(buf, '|');
*buf_ptr = '\0';
port_num = xatoul_range(buf_ptr + 1, 0, 65535);
if (ENABLE_FEATURE_IPV6 && ftpcmd("EPSV", NULL) == 229) {
/* good */
} else if (ftpcmd("PASV", NULL) != 227) {
ftp_die("PASV");
}
port_num = parse_pasv_epsv(buf);
if (port_num < 0)
ftp_die("PASV");
set_nport(&lsa->u.sa, htons(port_num));
return xconnect_stream(lsa);