网络系统调用网络套接字入口函数

网络套接字入口函数

//所有的网络套接字系统调用函数（socket bind listen connect ）都使用一个共同的入口函数：sys_socketcall
/*
第一个参数call表示被调用的应用层接口函数，第二个参数是一个指针，指向具体被调用函数（如accept函数）所需要的参数。
这些在用户系统调用时传入的参数将原封不动地传递给内核网络栈相关底层函数使用
*/
asmlinkage int sys_socketcall(int call, unsigned long *args)

int er;
switch(call)
{
case SYS_SOCKET:
er=verify_area(VERIFY_READ, args, 3 * sizeof(long));
if(er)
return er;
return(sock_socket(get_fs_long(args+0),
get_fs_long(args+1),
get_fs_long(args+2)));
case SYS_BIND:
er=verify_area(VERIFY_READ, args, 3 * sizeof(long));
if(er)
return er;
return(sock_bind(get_fs_long(args+0),
(struct sockaddr *)get_fs_long(args+1),
get_fs_long(args+2)));
case SYS_CONNECT:
er=verify_area(VERIFY_READ, args, 3 * sizeof(long));
if(er)
return er;
return(sock_connect(get_fs_long(args+0),
(struct sockaddr *)get_fs_long(args+1),
get_fs_long(args+2)));
case SYS_LISTEN:
er=verify_area(VERIFY_READ, args, 2 * sizeof(long));
if(er)
return er;
return(sock_listen(get_fs_long(args+0),
get_fs_long(args+1)));
case SYS_ACCEPT:
er=verify_area(VERIFY_READ, args, 3 * sizeof(long));
if(er)
return er;
return(sock_accept(get_fs_long(args+0),
(struct sockaddr *)get_fs_long(args+1),
(int *)get_fs_long(args+2)));
case SYS_GETSOCKNAME:
er=verify_area(VERIFY_READ, args, 3 * sizeof(long));
if(er)
return er;
return(sock_getsockname(get_fs_long(args+0),
(struct sockaddr *)get_fs_long(args+1),
(int *)get_fs_long(args+2)));
case SYS_GETPEERNAME:
er=verify_area(VERIFY_READ, args, 3 * sizeof(long));
if(er)
return er;
return(sock_getpeername(get_fs_long(args+0),
(struct sockaddr *)get_fs_long(args+1),
(int *)get_fs_long(args+2)));
case SYS_SOCKETPAIR:
er=verify_area(VERIFY_READ, args, 4 * sizeof(long));
if(er)
return er;
return(sock_socketpair(get_fs_long(args+0),
get_fs_long(args+1),
get_fs_long(args+2),
(unsigned long *)get_fs_long(args+3)));
case SYS_SEND:
er=verify_area(VERIFY_READ, args, 4 * sizeof(unsigned long));
if(er)
return er;
return(sock_send(get_fs_long(args+0),
(void *)get_fs_long(args+1),
get_fs_long(args+2),
get_fs_long(args+3)));
case SYS_SENDTO:
er=verify_area(VERIFY_READ, args, 6 * sizeof(unsigned long));
if(er)
return er;
return(sock_sendto(get_fs_long(args+0),
(void *)get_fs_long(args+1),
get_fs_long(args+2),
get_fs_long(args+3),
(struct sockaddr *)get_fs_long(args+4),
get_fs_long(args+5)));
case SYS_RECV:
er=verify_area(VERIFY_READ, args, 4 * sizeof(unsigned long));
if(er)
return er;
return(sock_recv(get_fs_long(args+0),
(void *)get_fs_long(args+1),
get_fs_long(args+2),
get_fs_long(args+3)));
case SYS_RECVFROM:
er=verify_area(VERIFY_READ, args, 6 * sizeof(unsigned long));
if(er)
return er;
return(sock_recvfrom(get_fs_long(args+0),
(void *)get_fs_long(args+1),
get_fs_long(args+2),
get_fs_long(args+3),
(struct sockaddr *)get_fs_long(args+4),
(int *)get_fs_long(args+5)));
case SYS_SHUTDOWN:
er=verify_area(VERIFY_READ, args, 2* sizeof(unsigned long));
if(er)
return er;
return(sock_shutdown(get_fs_long(args+0),
get_fs_long(args+1)));
case SYS_SETSOCKOPT:
er=verify_area(VERIFY_READ, args, 5*sizeof(unsigned long));
if(er)
return er;
return(sock_setsockopt(get_fs_long(args+0),
get_fs_long(args+1),
get_fs_long(args+2),
(char *)get_fs_long(args+3),
get_fs_long(args+4)));
case SYS_GETSOCKOPT:
er=verify_area(VERIFY_READ, args, 5*sizeof(unsigned long));
if(er)
return er;
return(sock_getsockopt(get_fs_long(args+0),
get_fs_long(args+1),
get_fs_long(args+2),
(char *)get_fs_long(args+3),
(int *)get_fs_long(args+4)));
default:
return(-EINVAL);
}
}