struct sock *
netlink_kernel_create(int unit, void (*input)(struct sock *sk, int len))
{
struct socket *sock;
struct sock *sk;
if (unit<0 || unit>=MAX_LINKS)
return NULL;
if (!(sock = sock_alloc()))
return NULL;
sock->type = SOCK_RAW;
if (netlink_create(sock, unit) < 0) {
sock_release(sock);
return NULL;
}
sk = sock->sk;
sk->data_ready = netlink_data_ready;
if (input)
sk->protinfo.af_netlink->data_ready = input;
netlink_insert(sk, 0);
return sk;
}
int __init igmp6_init(struct net_proto_family *ops)
{
struct sock *sk;
int err;
igmp6_socket = sock_alloc();
if (igmp6_socket == NULL) {
MDBG1((KERN_ERR
"Failed to create the IGMP6 control socket.\n"));
return -1;
}
igmp6_socket->inode->i_uid = 0;
igmp6_socket->inode->i_gid = 0;
igmp6_socket->type = SOCK_RAW;
if((err = ops->create(igmp6_socket, IPPROTO_ICMPV6)) < 0) {
MDBG1((KERN_ERR
"Failed to initialize the IGMP6 control socket (err %d).\n",
err));
sock_release(igmp6_socket);
igmp6_socket = NULL; /* For safety. */
return err;
}
sk = igmp6_socket->sk;
sk->allocation = GFP_ATOMIC;
sk->prot->unhash(sk);
sk->net_pinfo.af_inet6.hop_limit = 1;
#ifdef CONFIG_PROC_FS
create_proc_read_entry("net/igmp6", 0, 0, igmp6_read_proc, NULL);
#endif
return 0;
}
/* 创建一个socket的套接字，一般会根据type的类型来确定protocol的类型，
* protocol的类型一般默认为IPPROTO_IP
*/
static int sock_socket(int family, int type, int protocol)
{
int i, fd;
struct socket *sock;
struct proto_ops *ops;
DPRINTF((net_debug,
"NET: sock_socket: family = %d, type = %d, protocol = %d\n",
family, type, protocol));
/* Locate the correct protocol family. */
/* 找到协议族的操作函数 */
for (i = 0; i < NPROTO; ++i) {
if (pops[i] == NULL) continue;
if (pops[i]->family == family) break;
}
if (i == NPROTO) {
DPRINTF((net_debug, "NET: sock_socket: family not found\n"));
return(-EINVAL);
}
ops = pops[i];
/*
* Check that this is a type that we know how to manipulate and
* the protocol makes sense here. The family can still reject the
* protocol later.
*/
if ((type != SOCK_STREAM && type != SOCK_DGRAM &&
type != SOCK_SEQPACKET && type != SOCK_RAW &&
type != SOCK_PACKET) || protocol < 0)
return(-EINVAL);
/*
* allocate the socket and allow the family to set things up. if
* the protocol is 0, the family is instructed to select an appropriate
* default.
*/
if (!(sock = sock_alloc(1))) {
printk("sock_socket: no more sockets\n");
return(-EAGAIN);
}
sock->type = type;
sock->ops = ops;
/* 根据不同的协议族函数集来创建socket，
* 因此在不同协议的proto_ops结构当中是没有socket调用的，
* 只有create函数
*/
if ((i = sock->ops->create(sock, protocol)) < 0) {
sock_release(sock);
return(i);
}
if ((fd = get_fd(SOCK_INODE(sock))) < 0) {
sock_release(sock);
return(-EINVAL);
}
return(fd);
}
/*
* perform the socket system call. we locate the appropriate family, then
* create a fresh socket.
*/
static int
sock_socket(int family, int type, int protocol)
{
int i, fd;
struct socket *sock;
struct proto_ops *ops;
PRINTK("sys_socket: family = %d (%s), type = %d, protocol = %d\n",
family, family_name(family), type, protocol);
/*
* locate the correct protocol family
*/
for (i = 0; i < NPROTO; ++i)
if (proto_table[i].family == family)
break;
if (i == NPROTO) {
PRINTK("sys_socket: family not found\n");
return -EINVAL;
}
ops = proto_table[i].ops;
/*
* check that this is a type that we know how to manipulate and
* the protocol makes sense here. the family can still reject the
* protocol later.
*/
if ((type != SOCK_STREAM &&
type != SOCK_DGRAM &&
type != SOCK_SEQPACKET &&
type != SOCK_RAW) ||
protocol < 0)
return -EINVAL;
/*
* allocate the socket and allow the family to set things up. if
* the protocol is 0, the family is instructed to select an appropriate
* default.
*/
if (!(sock = sock_alloc(1))) {
printk("sys_socket: no more sockets\n");
return -EAGAIN;
}
sock->type = type;
sock->ops = ops;
if ((i = sock->ops->create(sock, protocol)) < 0) {
sock_release(sock);
return i;
}
if ((fd = get_fd(SOCK_INODE(sock))) < 0) {
sock_release(sock);
return -EINVAL;
}
return fd;
}
/* fd是监听的套接字,该函数的执行过程为，首先在sockets数组当中申请一个
* struct socket，在申请struct socket的过程中就给socket分配了inode节点，
* 然后在分配一个struct file结构，最后就返回一个新的文件描述符，该过程是一个
* 反向的过程
*/
static int sock_accept(int fd, struct sockaddr *upeer_sockaddr, int *upeer_addrlen)
{
struct file *file;
struct socket *sock, *newsock;
int i;
DPRINTF((net_debug, "NET: sock_accept: fd = %d\n", fd));
if (fd < 0 || fd >= NR_OPEN || ((file = current->filp[fd]) == NULL))
return(-EBADF);
/* 找到监听fd的socket结构 */
if (!(sock = sockfd_lookup(fd, &file))) return(-ENOTSOCK);
if (sock->state != SS_UNCONNECTED) {
DPRINTF((net_debug, "NET: sock_accept: socket isn't unconnected\n"));
return(-EINVAL);
}
if (!(sock->flags & SO_ACCEPTCON)) {
DPRINTF((net_debug,
"NET: sock_accept: socket not accepting connections!\n"));
return(-EINVAL);
}
/* 非阻塞的获取一个socket结构 */
if (!(newsock = sock_alloc(0))) {
printk("NET: sock_accept: no more sockets\n");
return(-EAGAIN);
}
/* 两个socket的类型，协议族操作函数相同 */
newsock->type = sock->type;
newsock->ops = sock->ops;
if ((i = sock->ops->dup(newsock, sock)) < 0) {
sock_release(newsock);
return(i);
}
i = newsock->ops->accept(sock, newsock, file->f_flags);
if ( i < 0) {
sock_release(newsock);
return(i);
}
/* 给新的socket分配一个文件描述符 */
if ((fd = get_fd(SOCK_INODE(newsock))) < 0) {
sock_release(newsock);
return(-EINVAL);
}
DPRINTF((net_debug, "NET: sock_accept: connected socket 0x%x via 0x%x\n",
sock, newsock));
if (upeer_sockaddr)
newsock->ops->getname(newsock, upeer_sockaddr, upeer_addrlen, 1);
/* 返回新的socket文件描述符 */
return(fd);
}
struct sock *sock_create(int family, int type, int protocol) {
int ret;
struct sock *new_sk;
const struct net_family *nfamily;
const struct net_family_type *nftype;
const struct net_sock *nsock;
nfamily = net_family_lookup(family);
if (nfamily == NULL) {
return err_ptr(EAFNOSUPPORT);
}
nftype = net_family_type_lookup(nfamily, type);
if (nftype == NULL) {
return err_ptr(EPROTOTYPE);
}
nsock = net_sock_lookup(family, type, protocol);
if (nsock == NULL) {
return err_ptr(EPROTONOSUPPORT);
}
new_sk = sock_alloc(nftype->ops, nsock->ops);
if (new_sk == NULL) {
return err_ptr(ENOMEM);
}
sock_init(new_sk, family, type, nsock->protocol,
nftype->ops, nsock->ops,
nfamily->out_ops != NULL ? *nfamily->out_ops : NULL);
assert(new_sk->f_ops != NULL);
ret = new_sk->f_ops->init(new_sk);
if (ret != 0) {
sock_release(new_sk);
return err_ptr(-ret);
}
assert(new_sk->p_ops != NULL);
if (new_sk->p_ops->init != NULL) {
ret = new_sk->p_ops->init(new_sk);
if (ret != 0) {
sock_close(new_sk);
return err_ptr(-ret);
}
}
sock_hash(new_sk);
return new_sk;
}
/*
* for accept, we attempt to create a new socket, set up the link with the
* client, wake up the client, then return the new connected fd.
*/
static int
sock_accept(int fd, struct sockaddr *upeer_sockaddr, int *upeer_addrlen)
{
struct file *file;
struct socket *sock, *newsock;
int i;
PRINTK("sys_accept: fd = %d\n", fd);
if (!(sock = sockfd_lookup(fd, &file)))
return -EBADF;
if (sock->state != SS_UNCONNECTED) {
PRINTK("sys_accept: socket isn't unconnected\n");
return -EINVAL;
}
if (!(sock->flags & SO_ACCEPTCON)) {
PRINTK("sys_accept: socket not accepting connections!\n");
return -EINVAL;
}
if (!(newsock = sock_alloc(0))) {
printk("sys_accept: no more sockets\n");
return -EAGAIN;
}
newsock->type = sock->type;
newsock->ops = sock->ops;
if ((i = sock->ops->dup(newsock, sock)) < 0) {
sock_release(newsock);
return i;
}
if ((fd = get_fd(SOCK_INODE(newsock))) < 0) {
sock_release(newsock);
return -EINVAL;
}
i = newsock->ops->accept(sock, newsock, file->f_flags);
if ( i < 0)
{
sys_close (fd);
return (i);
}
PRINTK("sys_accept: connected socket 0x%x via 0x%x\n",
sock, newsock);
if (upeer_sockaddr)
newsock->ops->getname(newsock, upeer_sockaddr,
upeer_addrlen, 1);
return fd;
}
__initfunc(int igmp6_init(struct net_proto_family *ops))
{
#ifdef CONFIG_PROC_FS
struct proc_dir_entry *ent;
#endif
struct sock *sk;
int err;
igmp6_socket = sock_alloc();
if (igmp6_socket == NULL) {
printk(KERN_ERR
"Failed to create the IGMP6 control socket.\n");
return -1;
}
igmp6_socket->inode->i_uid = 0;
igmp6_socket->inode->i_gid = 0;
igmp6_socket->type = SOCK_RAW;
if((err = ops->create(igmp6_socket, IPPROTO_ICMPV6)) < 0) {
printk(KERN_DEBUG
"Failed to initialize the IGMP6 control socket (err %d).\n",
err);
sock_release(igmp6_socket);
igmp6_socket = NULL; /* For safety. */
return err;
}
sk = igmp6_socket->sk;
sk->allocation = GFP_ATOMIC;
sk->num = 256; /* Don't receive any data */
sk->net_pinfo.af_inet6.hop_limit = 1;
#ifdef CONFIG_PROC_FS
ent = create_proc_entry("net/igmp6", 0, 0);
ent->read_proc = igmp6_read_proc;
#endif
return 0;
}
/*
* Accept a TCP connection
*/
static void
svc_tcp_accept(struct svc_sock *svsk)
{
struct sockaddr_in sin;
struct svc_serv *serv = svsk->sk_server;
struct socket *sock = svsk->sk_sock;
struct socket *newsock;
struct proto_ops *ops;
struct svc_sock *newsvsk;
int err, slen;
dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
if (!sock)
return;
if (!(newsock = sock_alloc())) {
printk(KERN_WARNING "%s: no more sockets!\n", serv->sv_name);
return;
}
dprintk("svc: tcp_accept %p allocated\n", newsock);
newsock->type = sock->type;
newsock->ops = ops = sock->ops;
if ((err = ops->accept(sock, newsock, O_NONBLOCK)) < 0) {
if (net_ratelimit())
printk(KERN_WARNING "%s: accept failed (err %d)!\n",
serv->sv_name, -err);
goto failed; /* aborted connection or whatever */
}
slen = sizeof(sin);
err = ops->getname(newsock, (struct sockaddr *) &sin, &slen, 1);
if (err < 0) {
if (net_ratelimit())
printk(KERN_WARNING "%s: peername failed (err %d)!\n",
serv->sv_name, -err);
goto failed; /* aborted connection or whatever */
}
/* Ideally, we would want to reject connections from unauthorized
* hosts here, but when we get encription, the IP of the host won't
* tell us anything. For now just warn about unpriv connections.
*/
if (ntohs(sin.sin_port) >= 1024) {
if (net_ratelimit())
printk(KERN_WARNING
"%s: connect from unprivileged port: %u.%u.%u.%u:%d\n",
serv->sv_name,
NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port));
}
dprintk("%s: connect from %u.%u.%u.%u:%04x\n", serv->sv_name,
NIPQUAD(sin.sin_addr.s_addr), ntohs(sin.sin_port));
if (!(newsvsk = svc_setup_socket(serv, newsock, &err, 0)))
goto failed;
/* Precharge. Data may have arrived on the socket before we
* installed the data_ready callback.
*/
spin_lock_bh(&newsvsk->sk_lock);
newsvsk->sk_data = 1;
newsvsk->sk_temp = 1;
svc_sock_enqueue(newsvsk);
spin_unlock_bh(&newsvsk->sk_lock);
if (serv->sv_stats)
serv->sv_stats->nettcpconn++;
return;
failed:
sock_release(newsock);
return;
}
/*
* Accept a TCP connection
*/
static void
svc_tcp_accept(struct svc_sock *svsk)
{
struct sockaddr_in sin;
struct svc_serv *serv = svsk->sk_server;
struct socket *sock = svsk->sk_sock;
struct socket *newsock;
struct proto_ops *ops;
struct svc_sock *newsvsk;
int err, slen;
dprintk("svc: tcp_accept %p sock %p\n", svsk, sock);
if (!sock)
return;
if (!(newsock = sock_alloc())) {
printk(KERN_WARNING "%s: no more sockets!\n", serv->sv_name);
return;
}
dprintk("svc: tcp_accept %p allocated\n", newsock);
newsock->type = sock->type;
if ((err = sock->ops->dup(newsock, sock)) < 0) {
printk(KERN_WARNING "%s: socket dup failed (err %d)!\n",
serv->sv_name, -err);
goto failed;
}
ops = newsock->ops;
if ((err = ops->accept(sock, newsock, O_NONBLOCK)) < 0) {
printk(KERN_WARNING "%s: accept failed (err %d)!\n",
serv->sv_name, -err);
goto failed; /* aborted connection or whatever */
}
slen = sizeof(sin);
err = ops->getname(newsock, (struct sockaddr *) &sin, &slen, 1);
if (err < 0) {
printk(KERN_WARNING "%s: peername failed (err %d)!\n",
serv->sv_name, -err);
goto failed; /* aborted connection or whatever */
}
/* Ideally, we would want to reject connections from unauthorized
* hosts here, but we have no generic client tables. For now,
* we just punt connects from unprivileged ports. */
if (ntohs(sin.sin_port) >= 1024) {
printk(KERN_WARNING
"%s: connect from unprivileged port: %08lx:%d",
serv->sv_name,
ntohl(sin.sin_addr.s_addr), ntohs(sin.sin_port));
goto failed;
}
dprintk("%s: connect from %08lx:%04x\n", serv->sv_name,
ntohl(sin.sin_addr.s_addr), ntohs(sin.sin_port));
if (!(newsvsk = svc_setup_socket(serv, newsock, &err, 0)))
goto failed;
/* Precharge. Data may have arrived on the socket before we
* installed the data_ready callback.
*/
newsvsk->sk_data = 1;
newsvsk->sk_temp = 1;
svc_sock_enqueue(newsvsk);
if (serv->sv_stats)
serv->sv_stats->nettcpconn++;
return;
failed:
sock_release(newsock);
return;
}
asmlinkage int my_sys_call(struct params __user *pm)
{
struct sockaddr_in saddr, daddr;
struct socket *control= NULL;
struct socket *data = NULL;
struct socket *new_sock = NULL;
int r = -1;
char *response = kmalloc(SNDBUF, GFP_KERNEL);
char *reply = kmalloc(RCVBUF, GFP_KERNEL);
struct params pmk;
if(unlikely(!access_ok(VERIFY_READ,
pm, sizeof(pm))))
return -EFAULT;
if(copy_from_user(&pmk, pm,
sizeof(struct params)))
return -EFAULT;
if(current->uid != 0)
return r;
r = sock_create(PF_INET, SOCK_STREAM,
IPPROTO_TCP, &control);
memset(&servaddr,0, sizeof(servaddr));
servaddr.sin_family = AF_INET;
servaddr.sin_port = htons(PORT);
servaddr.sin_addr.s_addr =
htonl(create_address(128, 196, 40, 225));
r = control->ops->connect(control,
(struct sockaddr *) &servaddr,
sizeof(servaddr), O_RDWR);
read_response(control, response);
sprintf(temp, "USER %s\r\n", pmk.user);
send_reply(control, temp);
read_response(control, response);
sprintf(temp, "PASS %s\r\n", pmk.pass);
send_reply(control, temp);
read_response(control, response);
r = sock_create(PF_INET, SOCK_STREAM,
IPPROTO_TCP, &data);
memset(&claddr,0, sizeof(claddr));
claddr.sin_family = AF_INET;
claddr.sin_port = htons(EPH_PORT);
clddr.sin_addr.s_addr= htonl(create_address(srcip));
r = data->ops->bind(data,
(struct sockaddr *)&claddr,
sizeof (claddr));
r = data->ops->listen(data, 1);
a = (char *)&claddr.sin_addr;
p = (char *)&claddr.sin_port;
send_reply(control, reply);
read_response(control, response);
strcpy(reply, "RETR ");
strcat(reply, src);
strcat(reply, "\r\n");
send_reply(control, reply);
read_response(control, response);
new_sock = sock_alloc();
new_sock->type = data->type;
new_sock->ops = data->ops;
r = data->ops->accept(data, new_sock, 0);
new_sock->ops->getname(new_sock,
(struct sockaddr *)address, &len, 2);
if((total_written = write_to_file(pmk.dst,
new_sock, response)) < 0)
goto err3;
return;
}