Bug 148038

Summary:

cryptographicallyRandomValuesFromOS should use arc4random_buf on Darwin.

Product:

WebKit

Reporter:

Keith Miller <keith_miller>

Component:

Web Template Framework

Assignee:

Nobody <webkit-unassigned>

Status:

RESOLVED FIXED

Severity:

Normal

CC:

ap, benjamin, cmarcelo, commit-queue

Priority:

Keywords:

InRadar

Version:

528+ (Nightly build)

Hardware:

Unspecified

OS:

Unspecified

See Also:

https://bugs.webkit.org/show_bug.cgi?id=146473

Attachments:

Description	Flags
Patch	none

Description Keith Miller 2015-08-14 13:39:55 PDT

Currently, we open a file descriptor to /dev/urandom, which can sometimes fail to open. Using arc4random_buf instead should get around this issue.

Comment 1 Keith Miller 2015-08-14 13:42:53 PDT

Created attachment 259034 [details]
Patch

Comment 2 Geoffrey Garen 2015-08-14 14:17:38 PDT

Comment on attachment 259034 [details]
Patch

r=me

Comment 3 WebKit Commit Bot 2015-08-14 15:01:58 PDT

Comment on attachment 259034 [details]
Patch

Clearing flags on attachment: 259034

Committed r188489: <http://trac.webkit.org/changeset/188489>

Comment 4 WebKit Commit Bot 2015-08-14 15:02:02 PDT

All reviewed patches have been landed.  Closing bug.

Comment 5 Alexey Proskuryakov 2015-08-15 13:13:35 PDT

This is a pretty surprising change. How did you come to this conclusion, and what other options have you considered? Is there even a bug anywhere tracking the symptom?

More specifically, how did you decide to not use CCRandomCopyBytes, and what can make opening /dev/urandom fail?

Comment 6 Keith Miller 2015-08-17 11:50:29 PDT

Whoops, I forgot to attach the associated radar (rdar://problem/21939126) to this bug. Alexey, I chose to use arc4random_buf because we just needed something that didn't open /dev/urandom. Although, looking into arc4random_buf further it appears that it opens /dev/urandom anyway.

Comment 7 Alexey Proskuryakov 2015-08-17 11:56:33 PDT

Thank you for the link!

> Although, looking into arc4random_buf further it appears that it opens /dev/urandom anyway.

Should the patch be rolled out then?

Comment 8 Keith Miller 2015-08-17 16:07:46 PDT

> Should the patch be rolled out then?

I'm not sure it's worth it. I am finishing up a patch that uses CCRandomCopyBytes instead. I'll CC you on that.