Wiring up direct socket calls on x86_32 Linux?

Wiring up direct socket calls on x86_32 Linux?

[Andy Lutomirski]

Hi all-

sys_socketcall sucks.  If nothing else, it's impossible to filter with
seccomp.  Should we wire up the real socket calls so that user code
can (very slowly) start migrating?

I think the list is:
 - socket
 - bind
 - connect
 - listen
 - accept4
 - getsockname
 - getpeername
 - socketpair
 - send
 - sendto
 - sendmsg
 - recv
 - recvfrom
 - recvmsg
 - shutdown
 - setsockopt

I skipped accept, which is superseded by accept4.  sendmmsg and
recvmmsg are already wired up.

Thoughts?  The patch would be trivial.

Glibc people: If Linux wired up the syscalls, would glibc use them?

--Andy

-- 
Andy Lutomirski
AMA Capital Management, LLC

Re: Wiring up direct socket calls on x86_32 Linux?

[Andreas Schwab]

Andy Lutomirski <luto@amacapital.net> writes:

> Glibc people: If Linux wired up the syscalls, would glibc use them?

Not automatically.  It needs to be compatible with the configured
minimum kernel version, so runtime probing would needed to be
implemented.

Andreas.

-- 
Andreas Schwab, schwab@linux-m68k.org
GPG Key fingerprint = 58CA 54C7 6D53 942B 1756  01D3 44D5 214B 8276 4ED5
"And now for something completely different."

Re: Wiring up direct socket calls on x86_32 Linux?

[Tulio Magno Quites Machado Filho]

Andy Lutomirski <luto@amacapital.net> writes:

> Hi all-
>
> sys_socketcall sucks.  If nothing else, it's impossible to filter with
> seccomp.  Should we wire up the real socket calls so that user code
> can (very slowly) start migrating?
>
> I think the list is:
>  - socket
>  - bind
>  - connect
>  - listen
>  - accept4
>  - getsockname
>  - getpeername
>  - socketpair
>  - send
>  - sendto
>  - sendmsg
>  - recv
>  - recvfrom
>  - recvmsg
>  - shutdown
>  - setsockopt

I guess you might want to follow the patch Raji sent today [1].

Her patch doesn't have all the syscalls you mentioned here, but has others too.
She will work to get a generic implementation for these functions.

[1] http://patchwork.sourceware.org/patch/7438/

-- 
Tulio Magno