[linux.git] / net / sunrpc / rpcb_clnt.c

/*
 * In-kernel rpcbind client supporting versions 2, 3, and 4 of the rpcbind
 * protocol
 *
 * Based on RFC 1833: "Binding Protocols for ONC RPC Version 2" and
 * RFC 3530: "Network File System (NFS) version 4 Protocol"
 *
 * Original: Gilles Quillard, Bull Open Source, 2005 <[email protected]>
 * Updated: Chuck Lever, Oracle Corporation, 2007 <[email protected]>
 *
 * Descended from net/sunrpc/pmap_clnt.c,
 *  Copyright (C) 1996, Olaf Kirch <[email protected]>
 */

#include <linux/module.h>

#include <linux/types.h>
#include <linux/socket.h>
#include <linux/in.h>
#include <linux/in6.h>
#include <linux/kernel.h>
#include <linux/errno.h>

#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.h>
#include <linux/sunrpc/xprtsock.h>

#ifdef RPC_DEBUG
# define RPCDBG_FACILITY	RPCDBG_BIND
#endif

#define RPCBIND_PROGRAM		(100000u)
#define RPCBIND_PORT		(111u)

enum {
	RPCBPROC_NULL,
	RPCBPROC_SET,
	RPCBPROC_UNSET,
	RPCBPROC_GETPORT,
	RPCBPROC_GETADDR = 3,		/* alias for GETPORT */
	RPCBPROC_DUMP,
	RPCBPROC_CALLIT,
	RPCBPROC_BCAST = 5,		/* alias for CALLIT */
	RPCBPROC_GETTIME,
	RPCBPROC_UADDR2TADDR,
	RPCBPROC_TADDR2UADDR,
	RPCBPROC_GETVERSADDR,
	RPCBPROC_INDIRECT,
	RPCBPROC_GETADDRLIST,
	RPCBPROC_GETSTAT,
};

#define RPCB_HIGHPROC_2		RPCBPROC_CALLIT
#define RPCB_HIGHPROC_3		RPCBPROC_TADDR2UADDR
#define RPCB_HIGHPROC_4		RPCBPROC_GETSTAT

/*
 * r_owner
 *
 * The "owner" is allowed to unset a service in the rpcbind database.
 * We always use the following (arbitrary) fixed string.
 */
#define RPCB_OWNER_STRING	"rpcb"
#define RPCB_MAXOWNERLEN	sizeof(RPCB_OWNER_STRING)

static void			rpcb_getport_done(struct rpc_task *, void *);
static struct rpc_program	rpcb_program;

struct rpcbind_args {
	struct rpc_xprt *	r_xprt;

	u32			r_prog;
	u32			r_vers;
	u32			r_prot;
	unsigned short		r_port;
	const char *		r_netid;
	const char *		r_addr;
	const char *		r_owner;
};

static struct rpc_procinfo rpcb_procedures2[];
static struct rpc_procinfo rpcb_procedures3[];

struct rpcb_info {
	int			rpc_vers;
	struct rpc_procinfo *	rpc_proc;
};

static struct rpcb_info rpcb_next_version[];
static struct rpcb_info rpcb_next_version6[];

static void rpcb_map_release(void *data)
{
	struct rpcbind_args *map = data;

	xprt_put(map->r_xprt);
	kfree(map);
}

static const struct rpc_call_ops rpcb_getport_ops = {
	.rpc_call_done		= rpcb_getport_done,
	.rpc_release		= rpcb_map_release,
};

static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
{
	xprt_clear_binding(xprt);
	rpc_wake_up_status(&xprt->binding, status);
}

static struct rpc_clnt *rpcb_create(char *hostname, struct sockaddr *srvaddr,
				    size_t salen, int proto, u32 version,
				    int privileged)
{
	struct rpc_create_args args = {
		.protocol	= proto,
		.address	= srvaddr,
		.addrsize	= salen,
		.servername	= hostname,
		.program	= &rpcb_program,
		.version	= version,
		.authflavor	= RPC_AUTH_UNIX,
		.flags		= RPC_CLNT_CREATE_NOPING,
	};

	switch (srvaddr->sa_family) {
	case AF_INET:
		((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
		break;
	case AF_INET6:
		((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
		break;
	default:
		return NULL;
	}

	if (!privileged)
		args.flags |= RPC_CLNT_CREATE_NONPRIVPORT;
	return rpc_create(&args);
}

/**
 * rpcb_register - set or unset a port registration with the local rpcbind svc
 * @prog: RPC program number to bind
 * @vers: RPC version number to bind
 * @prot: transport protocol to use to make this request
 * @port: port value to register
 * @okay: result code
 *
 * port == 0 means unregister, port != 0 means register.
 *
 * This routine supports only rpcbind version 2.
 */
int rpcb_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
{
	struct sockaddr_in sin = {
		.sin_family		= AF_INET,
		.sin_addr.s_addr	= htonl(INADDR_LOOPBACK),
	};
	struct rpcbind_args map = {
		.r_prog		= prog,
		.r_vers		= vers,
		.r_prot		= prot,
		.r_port		= port,
	};
	struct rpc_message msg = {
		.rpc_proc	= &rpcb_procedures2[port ?
					RPCBPROC_SET : RPCBPROC_UNSET],
		.rpc_argp	= &map,
		.rpc_resp	= okay,
	};
	struct rpc_clnt *rpcb_clnt;
	int error = 0;

	dprintk("RPC:       %sregistering (%u, %u, %d, %u) with local "
			"rpcbind\n", (port ? "" : "un"),
			prog, vers, prot, port);

	rpcb_clnt = rpcb_create("localhost", (struct sockaddr *) &sin,
				sizeof(sin), XPRT_TRANSPORT_UDP, 2, 1);
	if (IS_ERR(rpcb_clnt))
		return PTR_ERR(rpcb_clnt);

	error = rpc_call_sync(rpcb_clnt, &msg, 0);

	rpc_shutdown_client(rpcb_clnt);
	if (error < 0)
		printk(KERN_WARNING "RPC: failed to contact local rpcbind "
				"server (errno %d).\n", -error);
	dprintk("RPC:       registration status %d/%d\n", error, *okay);

	return error;
}

/**
 * rpcb_getport_sync - obtain the port for an RPC service on a given host
 * @sin: address of remote peer
 * @prog: RPC program number to bind
 * @vers: RPC version number to bind
 * @prot: transport protocol to use to make this request
 *
 * Return value is the requested advertised port number,
 * or a negative errno value.
 *
 * Called from outside the RPC client in a synchronous task context.
 * Uses default timeout parameters specified by underlying transport.
 *
 * XXX: Needs to support IPv6
 */
int rpcb_getport_sync(struct sockaddr_in *sin, u32 prog, u32 vers, int prot)
{
	struct rpcbind_args map = {
		.r_prog		= prog,
		.r_vers		= vers,
		.r_prot		= prot,
		.r_port		= 0,
	};
	struct rpc_message msg = {
		.rpc_proc	= &rpcb_procedures2[RPCBPROC_GETPORT],
		.rpc_argp	= &map,
		.rpc_resp	= &map.r_port,
	};
	struct rpc_clnt	*rpcb_clnt;
	int status;

	dprintk("RPC:       %s(" NIPQUAD_FMT ", %u, %u, %d)\n",
		__func__, NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);

	rpcb_clnt = rpcb_create(NULL, (struct sockaddr *)sin,
				sizeof(*sin), prot, 2, 0);
	if (IS_ERR(rpcb_clnt))
		return PTR_ERR(rpcb_clnt);

	status = rpc_call_sync(rpcb_clnt, &msg, 0);
	rpc_shutdown_client(rpcb_clnt);

	if (status >= 0) {
		if (map.r_port != 0)
			return map.r_port;
		status = -EACCES;
	}
	return status;
}
EXPORT_SYMBOL_GPL(rpcb_getport_sync);

static struct rpc_task *rpcb_call_async(struct rpc_clnt *rpcb_clnt, struct rpcbind_args *map, struct rpc_procinfo *proc)
{
	struct rpc_message msg = {
		.rpc_proc = proc,
		.rpc_argp = map,
		.rpc_resp = &map->r_port,
	};
	struct rpc_task_setup task_setup_data = {
		.rpc_client = rpcb_clnt,
		.rpc_message = &msg,
		.callback_ops = &rpcb_getport_ops,
		.callback_data = map,
		.flags = RPC_TASK_ASYNC,
	};

	return rpc_run_task(&task_setup_data);
}

/**
 * rpcb_getport_async - obtain the port for a given RPC service on a given host
 * @task: task that is waiting for portmapper request
 *
 * This one can be called for an ongoing RPC request, and can be used in
 * an async (rpciod) context.
 */
void rpcb_getport_async(struct rpc_task *task)
{
	struct rpc_clnt *clnt = task->tk_client;
	struct rpc_procinfo *proc;
	u32 bind_version;
	struct rpc_xprt *xprt = task->tk_xprt;
	struct rpc_clnt	*rpcb_clnt;
	static struct rpcbind_args *map;
	struct rpc_task	*child;
	struct sockaddr_storage addr;
	struct sockaddr *sap = (struct sockaddr *)&addr;
	size_t salen;
	int status;

	dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
		task->tk_pid, __func__,
		clnt->cl_server, clnt->cl_prog, clnt->cl_vers, xprt->prot);

	/* Autobind on cloned rpc clients is discouraged */
	BUG_ON(clnt->cl_parent != clnt);

	if (xprt_test_and_set_binding(xprt)) {
		status = -EAGAIN;	/* tell caller to check again */
		dprintk("RPC: %5u %s: waiting for another binder\n",
			task->tk_pid, __func__);
		goto bailout_nowake;
	}

	/* Put self on queue before sending rpcbind request, in case
	 * rpcb_getport_done completes before we return from rpc_run_task */
	rpc_sleep_on(&xprt->binding, task, NULL);

	/* Someone else may have bound if we slept */
	if (xprt_bound(xprt)) {
		status = 0;
		dprintk("RPC: %5u %s: already bound\n",
			task->tk_pid, __func__);
		goto bailout_nofree;
	}

	salen = rpc_peeraddr(clnt, sap, sizeof(addr));

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

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

	rpcb_clnt = rpcb_create(clnt->cl_server, sap, salen, 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, __func__, 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, __func__);
		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);
	map->r_addr = rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR);
	map->r_owner = RPCB_OWNER_STRING;	/* ignored for GETADDR */

	child = rpcb_call_async(rpcb_clnt, map, proc);
	rpc_release_client(rpcb_clnt);
	if (IS_ERR(child)) {
		status = -EIO;
		/* rpcb_map_release() has freed the arguments */
		dprintk("RPC: %5u %s: rpc_run_task failed\n",
			task->tk_pid, __func__);
		goto bailout_nofree;
	}
	rpc_put_task(child);

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

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 > RPCBIND_MAXUADDRLEN)
		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(RPCBIND_MAXUADDRLEN))
#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,
};
Commit	Line	Data
a509050b CL	1	/*
	2	* In-kernel rpcbind client supporting versions 2, 3, and 4 of the rpcbind
	3	* protocol
	4	*
	5	* Based on RFC 1833: "Binding Protocols for ONC RPC Version 2" and
	6	* RFC 3530: "Network File System (NFS) version 4 Protocol"
	7	*
	8	* Original: Gilles Quillard, Bull Open Source, 2005 <[email protected]>
	9	* Updated: Chuck Lever, Oracle Corporation, 2007 <[email protected]>
	10	*
	11	* Descended from net/sunrpc/pmap_clnt.c,
	12	* Copyright (C) 1996, Olaf Kirch <[email protected]>
	13	*/
	14
cce63cd6 CL	15	#include <linux/module.h>
cce63cd6 CL	16
a509050b CL	17	#include <linux/types.h>
a509050b CL	18	#include <linux/socket.h>
d5b64430 CL	19	#include <linux/in.h>
d5b64430 CL	20	#include <linux/in6.h>
a509050b CL	21	#include <linux/kernel.h>
	22	#include <linux/errno.h>
	23
	24	#include <linux/sunrpc/clnt.h>
	25	#include <linux/sunrpc/sched.h>
0896a725	26	#include <linux/sunrpc/xprtsock.h>
a509050b CL	27
	28	#ifdef RPC_DEBUG
	29	# define RPCDBG_FACILITY RPCDBG_BIND
	30	#endif
	31
	32	#define RPCBIND_PROGRAM (100000u)
	33	#define RPCBIND_PORT (111u)
	34
	35	enum {
	36	RPCBPROC_NULL,
	37	RPCBPROC_SET,
	38	RPCBPROC_UNSET,
	39	RPCBPROC_GETPORT,
	40	RPCBPROC_GETADDR = 3, /* alias for GETPORT */
	41	RPCBPROC_DUMP,
	42	RPCBPROC_CALLIT,
	43	RPCBPROC_BCAST = 5, /* alias for CALLIT */
	44	RPCBPROC_GETTIME,
	45	RPCBPROC_UADDR2TADDR,
	46	RPCBPROC_TADDR2UADDR,
	47	RPCBPROC_GETVERSADDR,
	48	RPCBPROC_INDIRECT,
	49	RPCBPROC_GETADDRLIST,
	50	RPCBPROC_GETSTAT,
	51	};
	52
	53	#define RPCB_HIGHPROC_2 RPCBPROC_CALLIT
	54	#define RPCB_HIGHPROC_3 RPCBPROC_TADDR2UADDR
	55	#define RPCB_HIGHPROC_4 RPCBPROC_GETSTAT
	56
a509050b CL	57	/*
	58	* r_owner
	59	*
	60	* The "owner" is allowed to unset a service in the rpcbind database.
	61	* We always use the following (arbitrary) fixed string.
	62	*/
	63	#define RPCB_OWNER_STRING "rpcb"
	64	#define RPCB_MAXOWNERLEN sizeof(RPCB_OWNER_STRING)
	65
	66	static void rpcb_getport_done(struct rpc_task , void );
7f4adeff	67	static struct rpc_program rpcb_program;
a509050b CL	68
	69	struct rpcbind_args {
	70	struct rpc_xprt * r_xprt;
	71
	72	u32 r_prog;
	73	u32 r_vers;
	74	u32 r_prot;
	75	unsigned short r_port;
86d61d86 TM	76	const char * r_netid;
	77	const char * r_addr;
	78	const char * r_owner;
a509050b CL	79	};
	80
	81	static struct rpc_procinfo rpcb_procedures2[];
	82	static struct rpc_procinfo rpcb_procedures3[];
	83
d5b64430	84	struct rpcb_info {
a509050b CL	85	int rpc_vers;
a509050b CL	86	struct rpc_procinfo * rpc_proc;
d5b64430 CL	87	};
	88
	89	static struct rpcb_info rpcb_next_version[];
	90	static struct rpcb_info rpcb_next_version6[];
a509050b	91
a509050b CL	92	static void rpcb_map_release(void *data)
	93	{
	94	struct rpcbind_args *map = data;
	95
	96	xprt_put(map->r_xprt);
	97	kfree(map);
	98	}
	99
	100	static const struct rpc_call_ops rpcb_getport_ops = {
a509050b CL	101	.rpc_call_done = rpcb_getport_done,
	102	.rpc_release = rpcb_map_release,
	103	};
	104
	105	static void rpcb_wake_rpcbind_waiters(struct rpc_xprt *xprt, int status)
	106	{
	107	xprt_clear_binding(xprt);
	108	rpc_wake_up_status(&xprt->binding, status);
	109	}
	110
	111	static struct rpc_clnt rpcb_create(char hostname, struct sockaddr *srvaddr,
0a48f5d7	112	size_t salen, int proto, u32 version,
9f6ad26d	113	int privileged)
a509050b CL	114	{
	115	struct rpc_create_args args = {
	116	.protocol = proto,
	117	.address = srvaddr,
9f6ad26d	118	.addrsize = salen,
a509050b CL	119	.servername = hostname,
	120	.program = &rpcb_program,
	121	.version = version,
	122	.authflavor = RPC_AUTH_UNIX,
150030b7	123	.flags = RPC_CLNT_CREATE_NOPING,
a509050b CL	124	};
a509050b CL	125
d5b64430 CL	126	switch (srvaddr->sa_family) {
	127	case AF_INET:
	128	((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
	129	break;
	130	case AF_INET6:
	131	((struct sockaddr_in6 *)srvaddr)->sin6_port = htons(RPCBIND_PORT);
	132	break;
	133	default:
	134	return NULL;
	135	}
	136
a509050b CL	137	if (!privileged)
	138	args.flags \|= RPC_CLNT_CREATE_NONPRIVPORT;
	139	return rpc_create(&args);
	140	}
	141
	142	/**
	143	* rpcb_register - set or unset a port registration with the local rpcbind svc
	144	* @prog: RPC program number to bind
	145	* @vers: RPC version number to bind
	146	* @prot: transport protocol to use to make this request
	147	* @port: port value to register
	148	* @okay: result code
	149	*
	150	* port == 0 means unregister, port != 0 means register.
	151	*
	152	* This routine supports only rpcbind version 2.
	153	*/
	154	int rpcb_register(u32 prog, u32 vers, int prot, unsigned short port, int *okay)
	155	{
	156	struct sockaddr_in sin = {
	157	.sin_family = AF_INET,
	158	.sin_addr.s_addr = htonl(INADDR_LOOPBACK),
	159	};
	160	struct rpcbind_args map = {
	161	.r_prog = prog,
	162	.r_vers = vers,
	163	.r_prot = prot,
	164	.r_port = port,
	165	};
	166	struct rpc_message msg = {
	167	.rpc_proc = &rpcb_procedures2[port ?
	168	RPCBPROC_SET : RPCBPROC_UNSET],
	169	.rpc_argp = &map,
	170	.rpc_resp = okay,
	171	};
	172	struct rpc_clnt *rpcb_clnt;
	173	int error = 0;
	174
	175	dprintk("RPC: %sregistering (%u, %u, %d, %u) with local "
	176	"rpcbind\n", (port ? "" : "un"),
	177	prog, vers, prot, port);
	178
	179	rpcb_clnt = rpcb_create("localhost", (struct sockaddr *) &sin,
9f6ad26d	180	sizeof(sin), XPRT_TRANSPORT_UDP, 2, 1);
a509050b CL	181	if (IS_ERR(rpcb_clnt))
	182	return PTR_ERR(rpcb_clnt);
	183
	184	error = rpc_call_sync(rpcb_clnt, &msg, 0);
	185
90c5755f	186	rpc_shutdown_client(rpcb_clnt);
a509050b CL	187	if (error < 0)
	188	printk(KERN_WARNING "RPC: failed to contact local rpcbind "
	189	"server (errno %d).\n", -error);
	190	dprintk("RPC: registration status %d/%d\n", error, *okay);
	191
	192	return error;
	193	}
	194
a509050b	195	/**
cce63cd6	196	* rpcb_getport_sync - obtain the port for an RPC service on a given host
a509050b CL	197	* @sin: address of remote peer
	198	* @prog: RPC program number to bind
	199	* @vers: RPC version number to bind
	200	* @prot: transport protocol to use to make this request
	201	*
67d60213 CL	202	* Return value is the requested advertised port number,
	203	* or a negative errno value.
	204	*
a509050b	205	* Called from outside the RPC client in a synchronous task context.
cce63cd6	206	* Uses default timeout parameters specified by underlying transport.
a509050b	207	*
67d60213	208	* XXX: Needs to support IPv6
a509050b	209	*/
f1ec08cb	210	int rpcb_getport_sync(struct sockaddr_in *sin, u32 prog, u32 vers, int prot)
a509050b CL	211	{
	212	struct rpcbind_args map = {
	213	.r_prog = prog,
	214	.r_vers = vers,
	215	.r_prot = prot,
	216	.r_port = 0,
	217	};
	218	struct rpc_message msg = {
	219	.rpc_proc = &rpcb_procedures2[RPCBPROC_GETPORT],
	220	.rpc_argp = &map,
	221	.rpc_resp = &map.r_port,
	222	};
	223	struct rpc_clnt *rpcb_clnt;
a509050b CL	224	int status;
a509050b CL	225
cce63cd6	226	dprintk("RPC: %s(" NIPQUAD_FMT ", %u, %u, %d)\n",
0dc47877	227	__func__, NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);
a509050b	228
b91e101f	229	rpcb_clnt = rpcb_create(NULL, (struct sockaddr *)sin,
afc88112	230	sizeof(*sin), prot, 2, 0);
a509050b CL	231	if (IS_ERR(rpcb_clnt))
	232	return PTR_ERR(rpcb_clnt);
	233
	234	status = rpc_call_sync(rpcb_clnt, &msg, 0);
90c5755f	235	rpc_shutdown_client(rpcb_clnt);
a509050b CL	236
	237	if (status >= 0) {
	238	if (map.r_port != 0)
	239	return map.r_port;
	240	status = -EACCES;
	241	}
	242	return status;
	243	}
cce63cd6	244	EXPORT_SYMBOL_GPL(rpcb_getport_sync);
a509050b	245
803a9067	246	static struct rpc_task rpcb_call_async(struct rpc_clnt rpcb_clnt, struct rpcbind_args map, struct rpc_procinfo proc)
5138fde0 TM	247	{
5138fde0 TM	248	struct rpc_message msg = {
803a9067	249	.rpc_proc = proc,
5138fde0 TM	250	.rpc_argp = map,
	251	.rpc_resp = &map->r_port,
	252	};
	253	struct rpc_task_setup task_setup_data = {
	254	.rpc_client = rpcb_clnt,
	255	.rpc_message = &msg,
	256	.callback_ops = &rpcb_getport_ops,
	257	.callback_data = map,
	258	.flags = RPC_TASK_ASYNC,
	259	};
	260
	261	return rpc_run_task(&task_setup_data);
	262	}
	263
a509050b	264	/**
45160d62	265	* rpcb_getport_async - obtain the port for a given RPC service on a given host
a509050b CL	266	* @task: task that is waiting for portmapper request
	267	*
	268	* This one can be called for an ongoing RPC request, and can be used in
	269	* an async (rpciod) context.
	270	*/
45160d62	271	void rpcb_getport_async(struct rpc_task *task)
a509050b CL	272	{
a509050b CL	273	struct rpc_clnt *clnt = task->tk_client;
803a9067	274	struct rpc_procinfo *proc;
0a48f5d7	275	u32 bind_version;
a509050b CL	276	struct rpc_xprt *xprt = task->tk_xprt;
	277	struct rpc_clnt *rpcb_clnt;
	278	static struct rpcbind_args *map;
	279	struct rpc_task *child;
9f6ad26d CL	280	struct sockaddr_storage addr;
	281	struct sockaddr sap = (struct sockaddr )&addr;
	282	size_t salen;
a509050b CL	283	int status;
a509050b CL	284
45160d62	285	dprintk("RPC: %5u %s(%s, %u, %u, %d)\n",
0dc47877	286	task->tk_pid, __func__,
45160d62	287	clnt->cl_server, clnt->cl_prog, clnt->cl_vers, xprt->prot);
a509050b CL	288
	289	/* Autobind on cloned rpc clients is discouraged */
	290	BUG_ON(clnt->cl_parent != clnt);
	291
	292	if (xprt_test_and_set_binding(xprt)) {
2429cbf6	293	status = -EAGAIN; /* tell caller to check again */
45160d62	294	dprintk("RPC: %5u %s: waiting for another binder\n",
0dc47877	295	task->tk_pid, __func__);
a509050b CL	296	goto bailout_nowake;
	297	}
	298
	299	/* Put self on queue before sending rpcbind request, in case
	300	* rpcb_getport_done completes before we return from rpc_run_task */
5d00837b	301	rpc_sleep_on(&xprt->binding, task, NULL);
a509050b CL	302
	303	/* Someone else may have bound if we slept */
	304	if (xprt_bound(xprt)) {
	305	status = 0;
45160d62	306	dprintk("RPC: %5u %s: already bound\n",
0dc47877	307	task->tk_pid, __func__);
a509050b CL	308	goto bailout_nofree;
	309	}
	310
9f6ad26d	311	salen = rpc_peeraddr(clnt, sap, sizeof(addr));
d5b64430 CL	312
d5b64430 CL	313	/* Don't ever use rpcbind v2 for AF_INET6 requests */
9f6ad26d	314	switch (sap->sa_family) {
d5b64430	315	case AF_INET:
803a9067 TM	316	proc = rpcb_next_version[xprt->bind_index].rpc_proc;
803a9067 TM	317	bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
d5b64430 CL	318	break;
d5b64430 CL	319	case AF_INET6:
803a9067 TM	320	proc = rpcb_next_version6[xprt->bind_index].rpc_proc;
803a9067 TM	321	bind_version = rpcb_next_version6[xprt->bind_index].rpc_vers;
d5b64430 CL	322	break;
	323	default:
	324	status = -EAFNOSUPPORT;
	325	dprintk("RPC: %5u %s: bad address family\n",
0dc47877	326	task->tk_pid, __func__);
d5b64430 CL	327	goto bailout_nofree;
d5b64430 CL	328	}
803a9067	329	if (proc == NULL) {
a509050b	330	xprt->bind_index = 0;
906462af	331	status = -EPFNOSUPPORT;
45160d62	332	dprintk("RPC: %5u %s: no more getport versions available\n",
0dc47877	333	task->tk_pid, __func__);
a509050b CL	334	goto bailout_nofree;
a509050b CL	335	}
a509050b	336
45160d62	337	dprintk("RPC: %5u %s: trying rpcbind version %u\n",
0dc47877	338	task->tk_pid, __func__, bind_version);
a509050b	339
9f6ad26d	340	rpcb_clnt = rpcb_create(clnt->cl_server, sap, salen, xprt->prot,
143b6c40 CL	341	bind_version, 0);
	342	if (IS_ERR(rpcb_clnt)) {
	343	status = PTR_ERR(rpcb_clnt);
	344	dprintk("RPC: %5u %s: rpcb_create failed, error %ld\n",
0dc47877	345	task->tk_pid, __func__, PTR_ERR(rpcb_clnt));
143b6c40 CL	346	goto bailout_nofree;
	347	}
	348
a509050b CL	349	map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
	350	if (!map) {
	351	status = -ENOMEM;
45160d62	352	dprintk("RPC: %5u %s: no memory available\n",
0dc47877	353	task->tk_pid, __func__);
a509050b CL	354	goto bailout_nofree;
	355	}
	356	map->r_prog = clnt->cl_prog;
	357	map->r_vers = clnt->cl_vers;
	358	map->r_prot = xprt->prot;
	359	map->r_port = 0;
	360	map->r_xprt = xprt_get(xprt);
86d61d86 TM	361	map->r_netid = rpc_peeraddr2str(clnt, RPC_DISPLAY_NETID);
86d61d86 TM	362	map->r_addr = rpc_peeraddr2str(rpcb_clnt, RPC_DISPLAY_UNIVERSAL_ADDR);
a509050b CL	363	map->r_owner = RPCB_OWNER_STRING; /* ignored for GETADDR */
a509050b CL	364
803a9067	365	child = rpcb_call_async(rpcb_clnt, map, proc);
4c402b40	366	rpc_release_client(rpcb_clnt);
a509050b CL	367	if (IS_ERR(child)) {
a509050b CL	368	status = -EIO;
0d3a34b4	369	/* rpcb_map_release() has freed the arguments */
45160d62	370	dprintk("RPC: %5u %s: rpc_run_task failed\n",
0dc47877	371	task->tk_pid, __func__);
0d3a34b4	372	goto bailout_nofree;
a509050b CL	373	}
	374	rpc_put_task(child);
	375
	376	task->tk_xprt->stat.bind_count++;
	377	return;
	378
a509050b CL	379	bailout_nofree:
	380	rpcb_wake_rpcbind_waiters(xprt, status);
	381	bailout_nowake:
	382	task->tk_status = status;
	383	}
12444809	384	EXPORT_SYMBOL_GPL(rpcb_getport_async);
a509050b CL	385
	386	/*
	387	* Rpcbind child task calls this callback via tk_exit.
	388	*/
	389	static void rpcb_getport_done(struct rpc_task child, void data)
	390	{
	391	struct rpcbind_args *map = data;
	392	struct rpc_xprt *xprt = map->r_xprt;
	393	int status = child->tk_status;
	394
4784cb51 CL	395	/* Garbage reply: retry with a lesser rpcbind version */
	396	if (status == -EIO)
	397	status = -EPROTONOSUPPORT;
	398
a509050b CL	399	/* rpcbind server doesn't support this rpcbind protocol version */
	400	if (status == -EPROTONOSUPPORT)
	401	xprt->bind_index++;
	402
	403	if (status < 0) {
	404	/* rpcbind server not available on remote host? */
	405	xprt->ops->set_port(xprt, 0);
	406	} else if (map->r_port == 0) {
	407	/* Requested RPC service wasn't registered on remote host */
	408	xprt->ops->set_port(xprt, 0);
	409	status = -EACCES;
	410	} else {
	411	/* Succeeded */
	412	xprt->ops->set_port(xprt, map->r_port);
	413	xprt_set_bound(xprt);
	414	status = 0;
	415	}
	416
	417	dprintk("RPC: %5u rpcb_getport_done(status %d, port %u)\n",
	418	child->tk_pid, status, map->r_port);
	419
	420	rpcb_wake_rpcbind_waiters(xprt, status);
	421	}
	422
	423	static int rpcb_encode_mapping(struct rpc_rqst req, __be32 p,
	424	struct rpcbind_args *rpcb)
	425	{
	426	dprintk("RPC: rpcb_encode_mapping(%u, %u, %d, %u)\n",
	427	rpcb->r_prog, rpcb->r_vers, rpcb->r_prot, rpcb->r_port);
	428	*p++ = htonl(rpcb->r_prog);
	429	*p++ = htonl(rpcb->r_vers);
	430	*p++ = htonl(rpcb->r_prot);
	431	*p++ = htonl(rpcb->r_port);
	432
	433	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
	434	return 0;
	435	}
	436
	437	static int rpcb_decode_getport(struct rpc_rqst req, __be32 p,
	438	unsigned short *portp)
	439	{
	440	portp = (unsigned short) ntohl(p++);
	441	dprintk("RPC: rpcb_decode_getport result %u\n",
	442	*portp);
	443	return 0;
	444	}
	445
	446	static int rpcb_decode_set(struct rpc_rqst req, __be32 p,
	447	unsigned int *boolp)
	448	{
	449	boolp = (unsigned int) ntohl(p++);
	450	dprintk("RPC: rpcb_decode_set result %u\n",
	451	*boolp);
	452	return 0;
	453	}
	454
	455	static int rpcb_encode_getaddr(struct rpc_rqst req, __be32 p,
	456	struct rpcbind_args *rpcb)
	457	{
	458	dprintk("RPC: rpcb_encode_getaddr(%u, %u, %s)\n",
	459	rpcb->r_prog, rpcb->r_vers, rpcb->r_addr);
	460	*p++ = htonl(rpcb->r_prog);
	461	*p++ = htonl(rpcb->r_vers);
	462
463	p = xdr_encode_string(p, rpcb->r_netid);
464	p = xdr_encode_string(p, rpcb->r_addr);
465	p = xdr_encode_string(p, rpcb->r_owner);
466
467	req->rq_slen = xdr_adjust_iovec(req->rq_svec, p);
468
469	return 0;
470	}
471
472	static int rpcb_decode_getaddr(struct rpc_rqst req, __be32 p,
473	unsigned short *portp)
474	{
475	char *addr;
adc24df8 CL	476	u32 addr_len;
adc24df8 CL	477	int c, i, f, first, val;
a509050b CL	478
a509050b CL	479	*portp = 0;
adc24df8	480	addr_len = ntohl(*p++);
a509050b	481
e65fe397 CL	482	/*
	483	* Simple sanity check. The smallest possible universal
	484	* address is an IPv4 address string containing 11 bytes.
	485	*/
0fb2b7e9	486	if (addr_len < 11 \|\| addr_len > RPCBIND_MAXUADDRLEN)
e65fe397 CL	487	goto out_err;
	488
	489	/*
	490	* Start at the end and walk backwards until the first dot
	491	* is encountered. When the second dot is found, we have
	492	* both parts of the port number.
	493	*/
a509050b CL	494	addr = (char *)p;
	495	val = 0;
	496	first = 1;
	497	f = 1;
	498	for (i = addr_len - 1; i > 0; i--) {
	499	c = addr[i];
	500	if (c >= '0' && c <= '9') {
	501	val += (c - '0') * f;
	502	f *= 10;
	503	} else if (c == '.') {
	504	if (first) {
	505	*portp = val;
	506	val = first = 0;
	507	f = 1;
	508	} else {
	509	*portp \|= (val << 8);
	510	break;
	511	}
	512	}
	513	}
	514
e65fe397 CL	515	/*
	516	* Simple sanity check. If we never saw a dot in the reply,
	517	* then this was probably just garbage.
	518	*/
	519	if (first)
	520	goto out_err;
	521
a509050b CL	522	dprintk("RPC: rpcb_decode_getaddr port=%u\n", *portp);
a509050b CL	523	return 0;
e65fe397 CL	524
	525	out_err:
	526	dprintk("RPC: rpcbind server returned malformed reply\n");
	527	return -EIO;
a509050b CL	528	}
	529
	530	#define RPCB_program_sz (1u)
	531	#define RPCB_version_sz (1u)
	532	#define RPCB_protocol_sz (1u)
	533	#define RPCB_port_sz (1u)
	534	#define RPCB_boolean_sz (1u)
	535
4f40ee4a	536	#define RPCB_netid_sz (1+XDR_QUADLEN(RPCBIND_MAXNETIDLEN))
0fb2b7e9	537	#define RPCB_addr_sz (1+XDR_QUADLEN(RPCBIND_MAXUADDRLEN))
a509050b CL	538	#define RPCB_ownerstring_sz (1+XDR_QUADLEN(RPCB_MAXOWNERLEN))
	539
	540	#define RPCB_mappingargs_sz RPCB_program_sz+RPCB_version_sz+ \
	541	RPCB_protocol_sz+RPCB_port_sz
	542	#define RPCB_getaddrargs_sz RPCB_program_sz+RPCB_version_sz+ \
	543	RPCB_netid_sz+RPCB_addr_sz+ \
	544	RPCB_ownerstring_sz
	545
	546	#define RPCB_setres_sz RPCB_boolean_sz
	547	#define RPCB_getportres_sz RPCB_port_sz
	548
	549	/*
	550	* Note that RFC 1833 does not put any size restrictions on the
	551	* address string returned by the remote rpcbind database.
	552	*/
	553	#define RPCB_getaddrres_sz RPCB_addr_sz
	554
	555	#define PROC(proc, argtype, restype) \
	556	[RPCBPROC_##proc] = { \
	557	.p_proc = RPCBPROC_##proc, \
	558	.p_encode = (kxdrproc_t) rpcb_encode_##argtype, \
	559	.p_decode = (kxdrproc_t) rpcb_decode_##restype, \
	560	.p_arglen = RPCB_##argtype##args_sz, \
	561	.p_replen = RPCB_##restype##res_sz, \
	562	.p_statidx = RPCBPROC_##proc, \
	563	.p_timer = 0, \
	564	.p_name = #proc, \
	565	}
	566
	567	/*
	568	* Not all rpcbind procedures described in RFC 1833 are implemented
	569	* since the Linux kernel RPC code requires only these.
	570	*/
	571	static struct rpc_procinfo rpcb_procedures2[] = {
	572	PROC(SET, mapping, set),
	573	PROC(UNSET, mapping, set),
	574	PROC(GETADDR, mapping, getport),
	575	};
	576
	577	static struct rpc_procinfo rpcb_procedures3[] = {
	578	PROC(SET, mapping, set),
	579	PROC(UNSET, mapping, set),
	580	PROC(GETADDR, getaddr, getaddr),
	581	};
	582
	583	static struct rpc_procinfo rpcb_procedures4[] = {
	584	PROC(SET, mapping, set),
	585	PROC(UNSET, mapping, set),
	586	PROC(GETVERSADDR, getaddr, getaddr),
	587	};
	588
	589	static struct rpcb_info rpcb_next_version[] = {
	590	#ifdef CONFIG_SUNRPC_BIND34
	591	{ 4, &rpcb_procedures4[RPCBPROC_GETVERSADDR] },
	592	{ 3, &rpcb_procedures3[RPCBPROC_GETADDR] },
	593	#endif
	594	{ 2, &rpcb_procedures2[RPCBPROC_GETPORT] },
	595	{ 0, NULL },
	596	};
	597
d5b64430 CL	598	static struct rpcb_info rpcb_next_version6[] = {
	599	#ifdef CONFIG_SUNRPC_BIND34
	600	{ 4, &rpcb_procedures4[RPCBPROC_GETVERSADDR] },
	601	{ 3, &rpcb_procedures3[RPCBPROC_GETADDR] },
	602	#endif
	603	{ 0, NULL },
	604	};
	605
a509050b CL	606	static struct rpc_version rpcb_version2 = {
	607	.number = 2,
	608	.nrprocs = RPCB_HIGHPROC_2,
	609	.procs = rpcb_procedures2
	610	};
	611
	612	static struct rpc_version rpcb_version3 = {
	613	.number = 3,
	614	.nrprocs = RPCB_HIGHPROC_3,
	615	.procs = rpcb_procedures3
	616	};
	617
	618	static struct rpc_version rpcb_version4 = {
	619	.number = 4,
	620	.nrprocs = RPCB_HIGHPROC_4,
	621	.procs = rpcb_procedures4
	622	};
	623
	624	static struct rpc_version *rpcb_version[] = {
	625	NULL,
	626	NULL,
	627	&rpcb_version2,
	628	&rpcb_version3,
	629	&rpcb_version4
	630	};
	631
	632	static struct rpc_stat rpcb_stats;
	633
7f4adeff	634	static struct rpc_program rpcb_program = {
a509050b CL	635	.name = "rpcbind",
	636	.number = RPCBIND_PROGRAM,
	637	.nrvers = ARRAY_SIZE(rpcb_version),
	638	.version = rpcb_version,
	639	.stats = &rpcb_stats,
	640	};