[patch 1/2][RFC] add socketat syscall

[Michael Kerrisk]

Hi Daniel,

Please CC linux-api on API/ABI changes.

See Documentation/SubmitChecklist and
http://thread.gmane.org/gmane.linux.ltp/5658.

Thanks,

Michael

On Fri, Oct 31, 2008 at 4:56 PM, Daniel Lezcano <dlezcano at fr.ibm.com> wrote:
> This patch adds the socketat syscall which allows to specify in
> which network namespace we want to create a socket. The network
> namespace destination is referred by a socket fd previously opened
> in the destination network namespace.
>
> Signed-off-by: Daniel Lezcano <dlezcano at fr.ibm.com>
> ---
>  arch/x86/include/asm/unistd_32.h   |    1
>  arch/x86/include/asm/unistd_64.h   |    3 +-
>  arch/x86/kernel/syscall_table_32.S |    1
>  include/linux/syscalls.h           |    1
>  kernel/sys_ni.c                    |    1
>  net/socket.c                       |   45 +++++++++++++++++++++++++++++++++++++
>  6 files changed, 51 insertions(+), 1 deletion(-)
>
> Index: net-next-2.6/arch/x86/include/asm/unistd_32.h
> ===================================================================
> --- net-next-2.6.orig/arch/x86/include/asm/unistd_32.h
> +++ net-next-2.6/arch/x86/include/asm/unistd_32.h
> @@ -338,6 +338,7 @@
>  #define __NR_dup3              330
>  #define __NR_pipe2             331
>  #define __NR_inotify_init1     332
> +#define __NR_socketat           333
>
>  #ifdef __KERNEL__
>
> Index: net-next-2.6/arch/x86/include/asm/unistd_64.h
> ===================================================================
> --- net-next-2.6.orig/arch/x86/include/asm/unistd_64.h
> +++ net-next-2.6/arch/x86/include/asm/unistd_64.h
> @@ -653,7 +653,8 @@ __SYSCALL(__NR_dup3, sys_dup3)
>  __SYSCALL(__NR_pipe2, sys_pipe2)
>  #define __NR_inotify_init1                     294
>  __SYSCALL(__NR_inotify_init1, sys_inotify_init1)
> -
> +#define __NR_socketat                           295
> +__SYSCALL(__NR_socketat, sys_socketat)
>
>  #ifndef __NO_STUBS
>  #define __ARCH_WANT_OLD_READDIR
> Index: net-next-2.6/arch/x86/kernel/syscall_table_32.S
> ===================================================================
> --- net-next-2.6.orig/arch/x86/kernel/syscall_table_32.S
> +++ net-next-2.6/arch/x86/kernel/syscall_table_32.S
> @@ -332,3 +332,4 @@ ENTRY(sys_call_table)
>        .long sys_dup3                  /* 330 */
>        .long sys_pipe2
>        .long sys_inotify_init1
> +       .long sys_socketat
> Index: net-next-2.6/net/socket.c
> ===================================================================
> --- net-next-2.6.orig/net/socket.c
> +++ net-next-2.6/net/socket.c
> @@ -1253,6 +1253,51 @@ out_release:
>        return retval;
>  }
>
> +asmlinkage long sys_socketat(int fd, int family, int type, int protocol)
> +{
> +       int retval, fput_needed;
> +       struct socket *sock;
> +       struct socket *sockat;
> +       struct net *net;
> +       int flags;
> +
> +       /* Check the SOCK_* constants for consistency.  */
> +       BUILD_BUG_ON(SOCK_CLOEXEC != O_CLOEXEC);
> +       BUILD_BUG_ON((SOCK_MAX | SOCK_TYPE_MASK) != SOCK_TYPE_MASK);
> +       BUILD_BUG_ON(SOCK_CLOEXEC & SOCK_TYPE_MASK);
> +       BUILD_BUG_ON(SOCK_NONBLOCK & SOCK_TYPE_MASK);
> +
> +       flags = type & ~SOCK_TYPE_MASK;
> +       if (flags & ~(SOCK_CLOEXEC | SOCK_NONBLOCK))
> +               return -EINVAL;
> +       type &= SOCK_TYPE_MASK;
> +
> +       if (SOCK_NONBLOCK != O_NONBLOCK && (flags & SOCK_NONBLOCK))
> +               flags = (flags & ~SOCK_NONBLOCK) | O_NONBLOCK;
> +
> +       sock = sockfd_lookup_light(fd, &retval, &fput_needed);
> +       if (!sock)
> +               goto out;
> +
> +       net = sock_net(sock->sk);
> +
> +       retval = __sock_create(net, family, type, protocol, &sockat, 0);
> +       if (retval)
> +               goto out_fput;
> +
> +       retval = sock_map_fd(sock, flags & (O_CLOEXEC | O_NONBLOCK));
> +       if (retval < 0)
> +               goto out_release;
> +out_fput:
> +       fput_light(sock->file, fput_needed);
> +out:
> +       return retval;
> +
> +out_release:
> +       sock_release(sockat);
> +       goto out;
> +}
> +
>  /*
>  *     Create a pair of connected sockets.
>  */
> Index: net-next-2.6/include/linux/syscalls.h
> ===================================================================
> --- net-next-2.6.orig/include/linux/syscalls.h
> +++ net-next-2.6/include/linux/syscalls.h
> @@ -423,6 +423,7 @@ asmlinkage long sys_recvfrom(int, void _
>                                struct sockaddr __user *, int __user *);
>  asmlinkage long sys_recvmsg(int fd, struct msghdr __user *msg, unsigned flags);
>  asmlinkage long sys_socket(int, int, int);
> +asmlinkage long sys_socketat(int, int, int, int);
>  asmlinkage long sys_socketpair(int, int, int, int __user *);
>  asmlinkage long sys_socketcall(int call, unsigned long __user *args);
>  asmlinkage long sys_listen(int, int);
> Index: net-next-2.6/kernel/sys_ni.c
> ===================================================================
> --- net-next-2.6.orig/kernel/sys_ni.c
> +++ net-next-2.6/kernel/sys_ni.c
> @@ -40,6 +40,7 @@ cond_syscall(sys_send);
>  cond_syscall(sys_recvfrom);
>  cond_syscall(sys_recv);
>  cond_syscall(sys_socket);
> +cond_syscall(sys_socketat);
>  cond_syscall(sys_setsockopt);
>  cond_syscall(compat_sys_setsockopt);
>  cond_syscall(sys_getsockopt);
>
> --
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>



-- 
Michael Kerrisk Linux man-pages maintainer;
http://www.kernel.org/doc/man-pages/ Found a documentation bug?
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