[Bug-wget] wget doesn't handle 5-digit port numbers in EPSV reponses
Dear wget authors,
When using wget --passive-ftp against IPv6 FTP servers, I occasionally
get the following error:
== EPSV
Cannot parse PASV response.
I finally found an FTP server that consistently had this problem today
(stunnel.mirt.net), and strace showed that the response in question was:
229 Entering Extended Passive Mode (|||49854|).
This is a perfectly valid response. wget is getting confused because of
an off-by-one error in the code that parses the port number in ftp_epsv.
When the port number is 5 digits long, i will be 5 at the end of the
loop, so the test for an invalid port number length should check for it
being *greater than* 5.
Here's the trivial fix:
* ftp-basic.c (ftp_epsv): Accept 5-digit port numbers in EPSV responses.
diff -x config.log -x config.status -ru tmp/wget-1.16.1/src/ftp-basic.c
work/wget-1.16.1/src/ftp-basic.c
--- tmp/wget-1.16.1/src/ftp-basic.c 2014-12-02 07:49:37.0 +
+++ work/wget-1.16.1/src/ftp-basic.c2015-01-04 16:06:02.28100 +
@@ -788,7 +788,7 @@
for (tport = 0, i = 0; i 5 c_isdigit (*s); i++, s++)
tport = (*s - '0') + 10 * tport;
- if (i = 5)
+ if (i 5)
{
xfree (respline);
return FTPINVPASV;
Thanks very much (and happy new year!),
--
Adam Sampson a...@offog.org http://offog.org/
Re: [Bug-wget] wget doesn't handle 5-digit port numbers in EPSV reponses
Am Sonntag, 4. Januar 2015, 16:19:01 schrieb Adam Sampson:
Dear wget authors,
When using wget --passive-ftp against IPv6 FTP servers, I occasionally
get the following error:
== EPSV
Cannot parse PASV response.
I finally found an FTP server that consistently had this problem today
(stunnel.mirt.net), and strace showed that the response in question was:
229 Entering Extended Passive Mode (|||49854|).
This is a perfectly valid response. wget is getting confused because of
an off-by-one error in the code that parses the port number in ftp_epsv.
When the port number is 5 digits long, i will be 5 at the end of the
loop, so the test for an invalid port number length should check for it
being *greater than* 5.
Here's the trivial fix:
* ftp-basic.c (ftp_epsv): Accept 5-digit port numbers in EPSV responses.
diff -x config.log -x config.status -ru tmp/wget-1.16.1/src/ftp-basic.c
work/wget-1.16.1/src/ftp-basic.c ---
tmp/wget-1.16.1/src/ftp-basic.c 2014-12-02 07:49:37.0 + +++
work/wget-1.16.1/src/ftp-basic.c 2015-01-04 16:06:02.28100 + @@
-788,7 +788,7 @@
for (tport = 0, i = 0; i 5 c_isdigit (*s); i++, s++)
tport = (*s - '0') + 10 * tport;
- if (i = 5)
+ if (i 5)
{
xfree (respline);
return FTPINVPASV;
Thanks very much (and happy new year!),
Happy New Year, Adam.
The loop condition is i 5, so when i becomes 5 the loop stops.
So how can i be 5 here ?
Tim
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Re: [Bug-wget] wget doesn't handle 5-digit port numbers in EPSV reponses
Am Sonntag, 4. Januar 2015, 18:57:23 schrieb Tim Rühsen:
Am Sonntag, 4. Januar 2015, 16:19:01 schrieb Adam Sampson:
Dear wget authors,
When using wget --passive-ftp against IPv6 FTP servers, I occasionally
get the following error:
== EPSV
Cannot parse PASV response.
I finally found an FTP server that consistently had this problem today
(stunnel.mirt.net), and strace showed that the response in question was:
229 Entering Extended Passive Mode (|||49854|).
This is a perfectly valid response. wget is getting confused because of
an off-by-one error in the code that parses the port number in ftp_epsv.
When the port number is 5 digits long, i will be 5 at the end of the
loop, so the test for an invalid port number length should check for it
being *greater than* 5.
Here's the trivial fix:
* ftp-basic.c (ftp_epsv): Accept 5-digit port numbers in EPSV responses.
diff -x config.log -x config.status -ru tmp/wget-1.16.1/src/ftp-basic.c
work/wget-1.16.1/src/ftp-basic.c ---
tmp/wget-1.16.1/src/ftp-basic.c 2014-12-02 07:49:37.0 + +++
work/wget-1.16.1/src/ftp-basic.c2015-01-04 16:06:02.28100 +
@@
-788,7 +788,7 @@
for (tport = 0, i = 0; i 5 c_isdigit (*s); i++, s++)
tport = (*s - '0') + 10 * tport;
- if (i = 5)
+ if (i 5)
{
xfree (respline);
return FTPINVPASV;
Thanks very much (and happy new year!),
Happy New Year, Adam.
The loop condition is i 5, so when i becomes 5 the loop stops.
So how can i be 5 here ?
Hehe, I was a bit too fast ;-)
i == 5 *is* a valid value after the loop, so you are right.
But since i never becomes 5, the checks does not make sense and we should
remove that check. Or change it to what is was meant to be (e.g. i==5
c_isdigit(*s)), I guess.
Tim
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Re: [Bug-wget] wget doesn't handle 5-digit port numbers in EPSV reponses
On Sun, Jan 04, 2015 at 07:06:05PM +0100, Tim Rühsen wrote: But since i never becomes 5, the checks does not make sense and we should remove that check. Or change it to what is was meant to be (e.g. i==5 c_isdigit(*s)), I guess. There's a check for whether the next character is the delimiter immediately afterwards, so just removing the check entirely should be fine. Cheers, -- Adam Sampson a...@offog.org http://offog.org/ pgpwKBD_KaQOD.pgp Description: PGP signature
Re: [Bug-wget] wget doesn't handle 5-digit port numbers in EPSV reponses
Am Sonntag, 4. Januar 2015, 18:39:05 schrieb Adam Sampson: On Sun, Jan 04, 2015 at 07:06:05PM +0100, Tim Rühsen wrote: But since i never becomes 5, the checks does not make sense and we should remove that check. Or change it to what is was meant to be (e.g. i==5 c_isdigit(*s)), I guess. There's a check for whether the next character is the delimiter immediately afterwards, so just removing the check entirely should be fine. Thanks, I pushed the appropriate patch. Tim signature.asc Description: This is a digitally signed message part.
