rpcb_clnt.c

linux 内核源代码

			task->tk_pid, __FUNCTION__);
		goto bailout_nofree;
	}

	rpc_peeraddr(clnt, (void *)&addr, sizeof(addr));

	/* Don't ever use rpcbind v2 for AF_INET6 requests */
	switch (addr.sa_family) {
	case AF_INET:
		info = rpcb_next_version;
		break;
	case AF_INET6:
		info = rpcb_next_version6;
		break;
	default:
		status = -EAFNOSUPPORT;
		dprintk("RPC: %5u %s: bad address family\n",
				task->tk_pid, __FUNCTION__);
		goto bailout_nofree;
	}
	if (info[xprt->bind_index].rpc_proc == NULL) {
		xprt->bind_index = 0;
		status = -EPFNOSUPPORT;
		dprintk("RPC: %5u %s: no more getport versions available\n",
			task->tk_pid, __FUNCTION__);
		goto bailout_nofree;
	}
	bind_version = info[xprt->bind_index].rpc_vers;

	dprintk("RPC: %5u %s: trying rpcbind version %u\n",
		task->tk_pid, __FUNCTION__, bind_version);

	rpcb_clnt = rpcb_create(clnt->cl_server, &addr, xprt->prot,
				bind_version, 0);
	if (IS_ERR(rpcb_clnt)) {
		status = PTR_ERR(rpcb_clnt);
		dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
			task->tk_pid, __FUNCTION__, PTR_ERR(rpcb_clnt));
		goto bailout_nofree;
	}

	map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
	if (!map) {
		status = -ENOMEM;
		dprintk("RPC: %5u %s: no memory available\n",
			task->tk_pid, __FUNCTION__);
		goto bailout_nofree;
	}
	map->r_prog = clnt->cl_prog;
	map->r_vers = clnt->cl_vers;
	map->r_prot = xprt->prot;
	map->r_port = 0;
	map->r_xprt = xprt_get(xprt);
	map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID);
	memcpy(map->r_addr,
	       rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR),
	       sizeof(map->r_addr));
	map->r_owner = RPCB_OWNER_STRING;	/* ignored for GETADDR */

	child = rpc_run_task(rpcb_clnt, RPC_TASK_ASYNC, &rpcb_getport_ops, map);
	rpc_release_client(rpcb_clnt);
	if (IS_ERR(child)) {
		status = -EIO;
		dprintk("RPC: %5u %s: rpc_run_task failed\n",
			task->tk_pid, __FUNCTION__);
		goto bailout;
	}
	rpc_put_task(child);

	task->tk_xprt->stat.bind_count++;
	return;

bailout:
	kfree(map);
	xprt_put(xprt);
bailout_nofree:
	rpcb_wake_rpcbind_waiters(xprt, status);
bailout_nowake:
	task->tk_status = status;
}
EXPORT_SYMBOL_GPL(rpcb_getport_async);

/*
 * Rpcbind child task calls this callback via tk_exit.
 */
static void rpcb_getport_done(struct rpc_task *child, void *data)
{
	struct rpcbind_args *map = data;
	struct rpc_xprt *xprt = map->r_xprt;
	int status = child->tk_status;

	/* Garbage reply: retry with a lesser rpcbind version */
	if (status == -EIO)
		status = -EPROTONOSUPPORT;

	/* rpcbind server doesn't support this rpcbind protocol version */
	if (status == -EPROTONOSUPPORT)
		xprt->bind_index++;

	if (status < 0) {
		/* rpcbind server not available on remote host? */
		xprt->ops->set_port(xprt, 0);
	} else if (map->r_port == 0) {
		/* Requested RPC service wasn't registered on remote host */
		xprt->ops->set_port(xprt, 0);
		status = -EACCES;
	} else {
		/* Succeeded */
		xprt->ops->set_port(xprt, map->r_port);
		xprt_set_bound(xprt);
		status = 0;
	}

	dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
			child->tk_pid, status, map->r_port);

	rpcb_wake_rpcbind_waiters(xprt, status);
}

static int rpcb_encode_mapping(struct rpc_rqst *req, __be32 *p,
			       struct rpcbind_args *rpcb)
{
	dprintk("RPC:       rpcb_encode_mapping(%u, %u, %d, %u)\n",
			rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
	*p++ = htonl(rpcb->r_prog);
	*p++ = htonl(rpcb->r_vers);
	*p++ = htonl(rpcb->r_prot);
	*p++ = htonl(rpcb->r_port);

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	return 0;
}

static int rpcb_decode_getport(struct rpc_rqst *req, __be32 *p,
			       unsigned short *portp)
{
	*portp = (unsigned short) ntohl(*p++);
	dprintk("RPC:      rpcb_decode_getport result %u\n",
			*portp);
	return 0;
}

static int rpcb_decode_set(struct rpc_rqst *req, __be32 *p,
			   unsigned int *boolp)
{
	*boolp = (unsigned int) ntohl(*p++);
	dprintk("RPC:      rpcb_decode_set result %u\n",
			*boolp);
	return 0;
}

static int rpcb_encode_getaddr(struct rpc_rqst *req, __be32 *p,
			       struct rpcbind_args *rpcb)
{
	dprintk("RPC:       rpcb_encode_getaddr(%u, %u, %s)\n",
			rpcb->r_prog, rpcb->r_vers, rpcb->r_addr);
	*p++ = htonl(rpcb->r_prog);
	*p++ = htonl(rpcb->r_vers);

	p = xdr_encode_string(p, rpcb->r_netid);
	p = xdr_encode_string(p, rpcb->r_addr);
	p = xdr_encode_string(p, rpcb->r_owner);

	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);

	return 0;
}

static int rpcb_decode_getaddr(struct rpc_rqst *req, __be32 *p,
			       unsigned short *portp)
{
	char *addr;
	u32 addr_len;
	int c, i, f, first, val;

	*portp = 0;
	addr_len = ntohl(*p++);

	/*
	 * Simple sanity check.  The smallest possible universal
	 * address is an IPv4 address string containing 11 bytes.
	 */
	if (addr_len < 11 || addr_len > RPCB_MAXADDRLEN)
		goto out_err;

	/*
	 * Start at the end and walk backwards until the first dot
	 * is encountered.  When the second dot is found, we have
	 * both parts of the port number.
	 */
	addr = (char *)p;
	val = 0;
	first = 1;
	f = 1;
	for (i = addr_len - 1; i > 0; i--) {
		c = addr[i];
		if (c >= '0' && c <= '9') {
			val += (c - '0') * f;
			f *= 10;
		} else if (c == '.') {
			if (first) {
				*portp = val;
				val = first = 0;
				f = 1;
			} else {
				*portp |= (val << 8);
				break;
			}
		}
	}

	/*
	 * Simple sanity check.  If we never saw a dot in the reply,
	 * then this was probably just garbage.
	 */
	if (first)
		goto out_err;

	dprintk("RPC:       rpcb_decode_getaddr port=%u\n", *portp);
	return 0;

out_err:
	dprintk("RPC:       rpcbind server returned malformed reply\n");
	return -EIO;
}

#define RPCB_program_sz		(1u)
#define RPCB_version_sz		(1u)
#define RPCB_protocol_sz	(1u)
#define RPCB_port_sz		(1u)
#define RPCB_boolean_sz		(1u)

#define RPCB_netid_sz		(1+XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
#define RPCB_addr_sz		(1+XDR_QUADLEN(RPCB_MAXADDRLEN))
#define RPCB_ownerstring_sz	(1+XDR_QUADLEN(RPCB_MAXOWNERLEN))

#define RPCB_mappingargs_sz	RPCB_program_sz+RPCB_version_sz+	\
				RPCB_protocol_sz+RPCB_port_sz
#define RPCB_getaddrargs_sz	RPCB_program_sz+RPCB_version_sz+	\
				RPCB_netid_sz+RPCB_addr_sz+		\
				RPCB_ownerstring_sz

#define RPCB_setres_sz		RPCB_boolean_sz
#define RPCB_getportres_sz	RPCB_port_sz

/*
 * Note that RFC 1833 does not put any size restrictions on the
 * address string returned by the remote rpcbind database.
 */
#define RPCB_getaddrres_sz	RPCB_addr_sz

#define PROC(proc, argtype, restype)					\
	[RPCBPROC_##proc] = {						\
		.p_proc		= RPCBPROC_##proc,			\
		.p_encode	= (kxdrproc_t) rpcb_encode_##argtype,	\
		.p_decode	= (kxdrproc_t) rpcb_decode_##restype,	\
		.p_arglen	= RPCB_##argtype##args_sz,		\
		.p_replen	= RPCB_##restype##res_sz,		\
		.p_statidx	= RPCBPROC_##proc,			\
		.p_timer	= 0,					\
		.p_name		= #proc,				\
	}

/*
 * Not all rpcbind procedures described in RFC 1833 are implemented
 * since the Linux kernel RPC code requires only these.
 */
static struct rpc_procinfo rpcb_procedures2[] = {
	PROC(SET,		mapping,	set),
	PROC(UNSET,		mapping,	set),
	PROC(GETADDR,		mapping,	getport),
};

static struct rpc_procinfo rpcb_procedures3[] = {
	PROC(SET,		mapping,	set),
	PROC(UNSET,		mapping,	set),
	PROC(GETADDR,		getaddr,	getaddr),
};

static struct rpc_procinfo rpcb_procedures4[] = {
	PROC(SET,		mapping,	set),
	PROC(UNSET,		mapping,	set),
	PROC(GETVERSADDR,	getaddr,	getaddr),
};

static struct rpcb_info rpcb_next_version[] = {
#ifdef CONFIG_SUNRPC_BIND34
	{ 4, &rpcb_procedures4[RPCBPROC_GETVERSADDR] },
	{ 3, &rpcb_procedures3[RPCBPROC_GETADDR] },
#endif
	{ 2, &rpcb_procedures2[RPCBPROC_GETPORT] },
	{ 0, NULL },
};

static struct rpcb_info rpcb_next_version6[] = {
#ifdef CONFIG_SUNRPC_BIND34
	{ 4, &rpcb_procedures4[RPCBPROC_GETVERSADDR] },
	{ 3, &rpcb_procedures3[RPCBPROC_GETADDR] },
#endif
	{ 0, NULL },
};

static struct rpc_version rpcb_version2 = {
	.number		= 2,
	.nrprocs	= RPCB_HIGHPROC_2,
	.procs		= rpcb_procedures2
};

static struct rpc_version rpcb_version3 = {
	.number		= 3,
	.nrprocs	= RPCB_HIGHPROC_3,
	.procs		= rpcb_procedures3
};

static struct rpc_version rpcb_version4 = {
	.number		= 4,
	.nrprocs	= RPCB_HIGHPROC_4,
	.procs		= rpcb_procedures4
};

static struct rpc_version *rpcb_version[] = {
	NULL,
	NULL,
	&rpcb_version2,
	&rpcb_version3,
	&rpcb_version4
};

static struct rpc_stat rpcb_stats;

static struct rpc_program rpcb_program = {
	.name		= "rpcbind",
	.number		= RPCBIND_PROGRAM,
	.nrvers		= ARRAY_SIZE(rpcb_version),
	.version	= rpcb_version,
	.stats		= &rpcb_stats,
};