13 May
2020
13 May
'20
2:56 p.m.
Hi all,
Does any one know the mathematical theory of below functions in:
https://github.com/ceph/ceph/blob/master/src/common/armor.c
1) ceph_armor
2) ceph_unarmor
B.R.
Changcheng
14 May
14 May
3:05 a.m.
(resending to include dev(a)ceph.io)
On 5/13/2020 7:56 AM, Liu, Changcheng wrote:
Hi all,
Does any one know the mathematical theory of below functions in:
https://github.com/ceph/ceph/blob/master/src/common/armor.c
1) ceph_armor
2) ceph_unarmor
B.R.
Changcheng
_______________________________________________
Dev mailing list -- dev(a)ceph.io
To unsubscribe send an email to dev-leave(a)ceph.io
It's just, as it says, base64 encoding; that is, it selects an ASCII
character for each 6 bits of the input. https://en.wikipedia.org/wiki/Base64
3:20 a.m.
Hi Dan Mick,
Thanks for your confirm.
Math is magic.
B.R.
Changcheng
On 20:05 Wed 13 May, Dan Mick wrote:
> (resending to include dev(a)ceph.io)
>
> On 5/13/2020 7:56 AM, Liu, Changcheng wrote:
> > Hi all,
> > Does any one know the mathematical theory of below functions in:
> > https://github.com/ceph/ceph/blob/master/src/common/armor.c
> > 1) ceph_armor
> > 2) ceph_unarmor
> >
> > B.R.
> > Changcheng
> > _______________________________________________
> > Dev mailing list -- dev(a)ceph.io
> > To unsubscribe send an email to dev-leave(a)ceph.io
> >
>
> It's just, as it says, base64 encoding; that is, it selects an ASCII
> character for each 6 bits of the input. https://en.wikipedia.org/wiki/Base64
> _______________________________________________
> Dev mailing list -- dev(a)ceph.io
> To unsubscribe send an email to dev-leave(a)ceph.io
2:54 p.m.
On Thu, May 14, 2020 at 6:06 AM Dan Mick <dmick(a)redhat.com> wrote:
(resending to include dev(a)ceph.io)
On 5/13/2020 7:56 AM, Liu, Changcheng wrote:
> Hi all,
> Does any one know the mathematical theory of below functions in:
> https://github.com/ceph/ceph/blob/master/src/common/armor.c
> 1) ceph_armor
> 2) ceph_unarmor
>
These are basic base64 conversions.
Yehuda
B.R.
Changcheng
_______________________________________________
Dev mailing list -- dev(a)ceph.io
To unsubscribe send an email to dev-leave(a)ceph.io
It's just, as it says, base64 encoding; that is, it selects an ASCII
character for each 6 bits of the input. https://en.wikipedia.org/wiki/Base64
_______________________________________________
Dev mailing list -- dev(a)ceph.io
To unsubscribe send an email to dev-leave(a)ceph.io
16 May
16 May
1:29 p.m.
New subject: base64 standard in Ceph
Hi all,
I'm trying to accelerate base64 encode/decode in Ceph.
There's one contradictory logic in ceph_armor & ceph_unarmor:
1. ceph_armor:
It won't add new breakline '\n' in the encoded result.
https://github.com/ceph/ceph/blob/master/src/common/armor.c#L85
Note: line_width is always 0
https://github.com/ceph/ceph/blob/master/src/common/armor.c#L96
2. ceph_unarmor:
It will use specific logic to deal with the new breakline in '\n'
https://github.com/ceph/ceph/blob/master/src/common/armor.c#L106
Why do we implement it in this way? Which version of base64 RFC is
followd by Ceph?
B.R.
Changcheng
17 May
17 May
7:27 a.m.
New subject: base64 standard in Ceph
On Sat, May 16, 2020 at 4:33 PM Liu, Changcheng
<changcheng.liu(a)intel.com> wrote:
Hi all,
I'm trying to accelerate base64 encode/decode in Ceph.
There's one contradictory logic in ceph_armor & ceph_unarmor:
1. ceph_armor:
It won't add new breakline '\n' in the encoded result.
https://github.com/ceph/ceph/blob/master/src/common/armor.c#L85
Note: line_width is always 0
https://github.com/ceph/ceph/blob/master/src/common/armor.c#L96
2. ceph_unarmor:
It will use specific logic to deal with the new breakline in '\n'
https://github.com/ceph/ceph/blob/master/src/common/armor.c#L106
Why do we implement it in this way? Which version of base64 RFC is
followd by Ceph?
It is common to have base64 strings that have line breaks in them, so
our decoding function needs to be able to handle that whether we use
it or not. We do have ceph_armor_line_break() that can be used in
theory (although it's not being used right now). There are cases where
we need to handle base64 strings that were encoded by external
sources, so code needs to be resilient and handle these cases.
Yehuda
1:40 p.m.
New subject: base64 standard in Ceph
On 10:27 Sun 17 May, Yehuda Sadeh-Weinraub wrote:
On Sat, May 16, 2020 at 4:33 PM Liu, Changcheng
<changcheng.liu(a)intel.com> wrote:
Could you show which acutal usage needs to decode the '\n' in the
encoded base64 string?
Which base64 RFC is followd by Ceph? What's extra changes are added
based the standard used RFC?
--Changcheng
>
> Yehuda
>
Hi all,
I'm trying to accelerate base64 encode/decode in Ceph.
Why do we implement it in this way? Which version of base64 RFC is
followd by Ceph?
It is common to have base64 strings that have line breaks in them, so
our decoding function needs to be able to handle that whether we use
it or not. We do have ceph_armor_line_break() that can be used in
theory (although it's not being used right now). There are cases where
we need to handle base64 strings that were encoded by external
sources, so code needs to be resilient and handle these cases.
19 May
19 May
11:39 p.m.
New subject: base64 standard in Ceph
On 5/17/2020 6:40 AM, Liu, Changcheng wrote:
On 10:27 Sun 17 May, Yehuda Sadeh-Weinraub wrote:
This seems like a very strange thing to focus on. The Ceph utility
routine has the capability to add line breaks if requested; so far, the
callers inside ceph do not add line breaks, but they could if desired.
The code also ignores line breaks on input. This is just a normal
coding decision, as the newline itself (or indeed any whitespace) is not
part of the coding domain.
Why do you find this to be an issue that requires attention?
On Sat, May 16, 2020 at 4:33 PM Liu, Changcheng
<changcheng.liu(a)intel.com> wrote:
Could you show which acutal usage needs to decode the '\n' in the
encoded base64 string?
Which base64 RFC is followd by Ceph? What's extra changes are added
based the standard used RFC?
Hi all,
I'm trying to accelerate base64 encode/decode in Ceph.
Why do we implement it in this way? Which version of base64 RFC is
followd by Ceph?
It is common to have base64 strings that have line breaks in them, so
our decoding function needs to be able to handle that whether we use
it or not. We do have ceph_armor_line_break() that can be used in
theory (although it's not being used right now). There are cases where
we need to handle base64 strings that were encoded by external
sources, so code needs to be resilient and handle these cases.
1457
days inactive
1463
days old
7 comments
3 participants
participants (3)
-
Dan Mick -
Liu, Changcheng -
Yehuda Sadeh-Weinraub