/*
* 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 <gilles.quillard@bull.net>
* Updated: Chuck Lever, Oracle Corporation, 2007 <chuck.lever@oracle.com>
*
* Descended from net/sunrpc/pmap_clnt.c,
* Copyright (C) 1996, Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/types.h>
#include <linux/socket.h>
#include <linux/kernel.h>
#include <linux/errno.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/sched.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_addr
*
* Quoting RFC 3530, section 2.2:
*
* For TCP over IPv4 and for UDP over IPv4, the format of r_addr is the
* US-ASCII string:
*
* h1.h2.h3.h4.p1.p2
*
* The prefix, "h1.h2.h3.h4", is the standard textual form for
* representing an IPv4 address, which is always four octets long.
* Assuming big-endian ordering, h1, h2, h3, and h4, are respectively,
* the first through fourth octets each converted to ASCII-decimal.
* Assuming big-endian ordering, p1 and p2 are, respectively, the first
* and second octets each converted to ASCII-decimal. For example, if a
* host, in big-endian order, has an address of 0x0A010307 and there is
* a service listening on, in big endian order, port 0x020F (decimal
* 527), then the complete universal address is "10.1.3.7.2.15".
*
* ...
*
* For TCP over IPv6 and for UDP over IPv6, the format of r_addr is the
* US-ASCII string:
*
* x1:x2:x3:x4:x5:x6:x7:x8.p1.p2
*
* The suffix "p1.p2" is the service port, and is computed the same way
* as with universal addresses for TCP and UDP over IPv4. The prefix,
* "x1:x2:x3:x4:x5:x6:x7:x8", is the standard textual form for
* representing an IPv6 address as defined in Section 2.2 of [RFC2373].
* Additionally, the two alternative forms specified in Section 2.2 of
* [RFC2373] are also acceptable.
*
* XXX: Currently this implementation does not explicitly convert the
* stored address to US-ASCII on non-ASCII systems.
*/
#define RPCB_MAXADDRLEN (128u)
/*
* r_netid
*
* Quoting RFC 3530, section 2.2:
*
* For TCP over IPv4 the value of r_netid is the string "tcp". For UDP
* over IPv4 the value of r_netid is the string "udp".
*
* ...
*
* For TCP over IPv6 the value of r_netid is the string "tcp6". For UDP
* over IPv6 the value of r_netid is the string "udp6".
*/
#define RPCB_NETID_UDP "\165\144\160" /* "udp" */
#define RPCB_NETID_TCP "\164\143\160" /* "tcp" */
#define RPCB_NETID_UDP6 "\165\144\160\066" /* "udp6" */
#define RPCB_NETID_TCP6 "\164\143\160\066" /* "tcp6" */
#define RPCB_MAXNETIDLEN (4u)
/*
* 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 *);
extern 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;
char * r_netid;
char r_addr[RPCB_MAXADDRLEN];
char * r_owner;
};
static struct rpc_procinfo rpcb_procedures2[];
static struct rpc_procinfo rpcb_procedures3[];
static struct rpcb_info {
int rpc_vers;
struct rpc_procinfo * rpc_proc;
} rpcb_next_version[];
static void rpcb_getport_prepare(struct rpc_task *task, void *calldata)
{
struct rpcbind_args *map = calldata;
struct rpc_xprt *xprt = map->r_xprt;
struct rpc_message msg = {
.rpc_proc = rpcb_next_version[xprt->bind_index].rpc_proc,
.rpc_argp = map,
.rpc_resp = &map->r_port,
};
rpc_call_setup(task, &msg, 0);
}
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_prepare = rpcb_getport_prepare,
.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,
int proto, int version, int privileged)
{
struct rpc_create_args args = {
.protocol = proto,
.address = srvaddr,
.addrsize = sizeof(struct sockaddr_in),
.servername = hostname,
.program = &rpcb_program,
.version = version,
.authflavor = RPC_AUTH_UNIX,
.flags = RPC_CLNT_CREATE_NOPING,
};
((struct sockaddr_in *)srvaddr)->sin_port = htons(RPCBIND_PORT);
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,
IPPROTO_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;
}
#ifdef CONFIG_ROOT_NFS
/**
* rpcb_getport_external - 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
*
* Called from outside the RPC client in a synchronous task context.
*
* For now, this supports only version 2 queries, but is used only by
* mount_clnt for NFS_ROOT.
*/
int rpcb_getport_external(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;
char hostname[40];
int status;
dprintk("RPC: rpcb_getport_external(%u.%u.%u.%u, %u, %u, %d)\n",
NIPQUAD(sin->sin_addr.s_addr), prog, vers, prot);
sprintf(hostname, "%u.%u.%u.%u", NIPQUAD(sin->sin_addr.s_addr));
rpcb_clnt = rpcb_create(hostname, (struct sockaddr *)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;
}
#endif
/**
* rpcb_getport - 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(struct rpc_task *task)
{
struct rpc_clnt *clnt = task->tk_client;
int 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 addr;
int status;
dprintk("RPC: %5u rpcb_getport(%s, %u, %u, %d)\n",
task->tk_pid, 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 = -EACCES; /* tell caller to check again */
dprintk("RPC: %5u rpcb_getport waiting for another binder\n",
task->tk_pid);
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, NULL);
/* Someone else may have bound if we slept */
if (xprt_bound(xprt)) {
status = 0;
dprintk("RPC: %5u rpcb_getport already bound\n", task->tk_pid);
goto bailout_nofree;
}
if (rpcb_next_version[xprt->bind_index].rpc_proc == NULL) {
xprt->bind_index = 0;
status = -EACCES; /* tell caller to try again later */
dprintk("RPC: %5u rpcb_getport no more getport versions "
"available\n", task->tk_pid);
goto bailout_nofree;
}
bind_version = rpcb_next_version[xprt->bind_index].rpc_vers;
dprintk("RPC: %5u rpcb_getport trying rpcbind version %u\n",
task->tk_pid, bind_version);
map = kzalloc(sizeof(struct rpcbind_args), GFP_ATOMIC);
if (!map) {
status = -ENOMEM;
dprintk("RPC: %5u rpcb_getport no memory available\n",
task->tk_pid);
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 = (xprt->prot == IPPROTO_TCP) ? RPCB_NETID_TCP :
RPCB_NETID_UDP;
memcpy(&map->r_addr, rpc_peeraddr2str(clnt, RPC_DISPLAY_ADDR),
sizeof(map->r_addr));
map->r_owner = RPCB_OWNER_STRING; /* ignored for GETADDR */
rpc_peeraddr(clnt, (void *)&addr, sizeof(addr));
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 rpcb_getport rpcb_create failed, error %ld\n",
task->tk_pid, PTR_ERR(rpcb_clnt));
goto bailout;
}
child = rpc_run_task(rpcb_clnt, RPC_TASK_ASYNC, &rpcb_getport_ops, map);
rpc_destroy_client(rpcb_clnt);
if (IS_ERR(child)) {
status = -EIO;
dprintk("RPC: %5u rpcb_getport rpc_run_task failed\n",
task->tk_pid);
goto bailout_nofree;
}
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;
}
/*
* 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;
/* 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;
int addr_len, c, i, f, first, val;
*portp = 0;
addr_len = (unsigned int) ntohl(*p++);
if (addr_len > RPCB_MAXADDRLEN) /* sanity */
return -EINVAL;
dprintk("RPC: rpcb_decode_getaddr returned string: '%s'\n",
(char *) p);
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;
}
}
}
dprintk("RPC: rpcb_decode_getaddr port=%u\n", *portp);
return 0;
}
#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(RPCB_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 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;
struct rpc_program rpcb_program = {
.name = "rpcbind",
.number = RPCBIND_PROGRAM,
.nrvers = ARRAY_SIZE(rpcb_version),
.version = rpcb_version,
.stats = &rpcb_stats,
};
