svc.c
/*
* linux/net/sunrpc/svc.c
*
* High-level RPC service routines
*
* Copyright (C) 1995, 1996 Olaf Kirch <okir@monad.swb.de>
*/
#include <linux/linkage.h>
#include <linux/sched.h>
#include <linux/errno.h>
#include <linux/net.h>
#include <linux/in.h>
#include <linux/mm.h>
#include <linux/sunrpc/types.h>
#include <linux/sunrpc/xdr.h>
#include <linux/sunrpc/stats.h>
#include <linux/sunrpc/svcsock.h>
#include <linux/sunrpc/clnt.h>
#define RPCDBG_FACILITY RPCDBG_SVCDSP
#define RPC_PARANOIA 1
/*
* Create an RPC service
*/
struct svc_serv *
svc_create(struct svc_program *prog, unsigned int bufsize)
{
struct svc_serv *serv;
int vers;
unsigned int xdrsize;
if (!(serv = kmalloc(sizeof(*serv), GFP_KERNEL)))
return NULL;
memset(serv, 0, sizeof(*serv));
serv->sv_name = prog->pg_name;
serv->sv_program = prog;
serv->sv_nrthreads = 1;
serv->sv_stats = prog->pg_stats;
serv->sv_bufsz = bufsize? bufsize : 4096;
xdrsize = 0;
while (prog) {
prog->pg_lovers = prog->pg_nvers-1;
for (vers=0; vers<prog->pg_nvers ; vers++)
if (prog->pg_vers[vers]) {
prog->pg_hivers = vers;
if (prog->pg_lovers > vers)
prog->pg_lovers = vers;
if (prog->pg_vers[vers]->vs_xdrsize > xdrsize)
xdrsize = prog->pg_vers[vers]->vs_xdrsize;
}
prog = prog->pg_next;
}
serv->sv_xdrsize = xdrsize;
INIT_LIST_HEAD(&serv->sv_threads);
INIT_LIST_HEAD(&serv->sv_sockets);
INIT_LIST_HEAD(&serv->sv_tempsocks);
INIT_LIST_HEAD(&serv->sv_permsocks);
spin_lock_init(&serv->sv_lock);
/* Remove any stale portmap registrations */
svc_register(serv, 0, 0);
return serv;
}
/*
* Destroy an RPC service
*/
void
svc_destroy(struct svc_serv *serv)
{
struct svc_sock *svsk;
dprintk("RPC: svc_destroy(%s, %d)\n",
serv->sv_program->pg_name,
serv->sv_nrthreads);
if (serv->sv_nrthreads) {
if (--(serv->sv_nrthreads) != 0) {
svc_sock_update_bufs(serv);
return;
}
} else
printk("svc_destroy: no threads for serv=%p!\n", serv);
while (!list_empty(&serv->sv_tempsocks)) {
svsk = list_entry(serv->sv_tempsocks.next,
struct svc_sock,
sk_list);
svc_delete_socket(svsk);
}
while (!list_empty(&serv->sv_permsocks)) {
svsk = list_entry(serv->sv_permsocks.next,
struct svc_sock,
sk_list);
svc_delete_socket(svsk);
}
cache_clean_deferred(serv);
/* Unregister service with the portmapper */
svc_register(serv, 0, 0);
kfree(serv);
}
/*
* Allocate an RPC server's buffer space.
* We allocate pages and place them in rq_argpages.
*/
static int
svc_init_buffer(struct svc_rqst *rqstp, unsigned int size)
{
int pages;
int arghi;
if (size > RPCSVC_MAXPAYLOAD)
size = RPCSVC_MAXPAYLOAD;
pages = 2 + (size+ PAGE_SIZE -1) / PAGE_SIZE;
rqstp->rq_argused = 0;
rqstp->rq_resused = 0;
arghi = 0;
BUG_ON(pages > RPCSVC_MAXPAGES);
while (pages) {
struct page *p = alloc_page(GFP_KERNEL);
if (!p)
break;
rqstp->rq_argpages[arghi++] = p;
pages--;
}
rqstp->rq_arghi = arghi;
return ! pages;
}
/*
* Release an RPC server buffer
*/
static void
svc_release_buffer(struct svc_rqst *rqstp)
{
while (rqstp->rq_arghi)
put_page(rqstp->rq_argpages[--rqstp->rq_arghi]);
while (rqstp->rq_resused) {
if (rqstp->rq_respages[--rqstp->rq_resused] == NULL)
continue;
put_page(rqstp->rq_respages[rqstp->rq_resused]);
}
rqstp->rq_argused = 0;
}
/*
* Create a server thread
*/
int
svc_create_thread(svc_thread_fn func, struct svc_serv *serv)
{
struct svc_rqst *rqstp;
int error = -ENOMEM;
rqstp = kmalloc(sizeof(*rqstp), GFP_KERNEL);
if (!rqstp)
goto out;
memset(rqstp, 0, sizeof(*rqstp));
init_waitqueue_head(&rqstp->rq_wait);
if (!(rqstp->rq_argp = kmalloc(serv->sv_xdrsize, GFP_KERNEL))
|| !(rqstp->rq_resp = kmalloc(serv->sv_xdrsize, GFP_KERNEL))
|| !svc_init_buffer(rqstp, serv->sv_bufsz))
goto out_thread;
serv->sv_nrthreads++;
rqstp->rq_server = serv;
error = kernel_thread((int (*)(void *)) func, rqstp, 0);
if (error < 0)
goto out_thread;
svc_sock_update_bufs(serv);
error = 0;
out:
return error;
out_thread:
svc_exit_thread(rqstp);
goto out;
}
/*
* Destroy an RPC server thread
*/
void
svc_exit_thread(struct svc_rqst *rqstp)
{
struct svc_serv *serv = rqstp->rq_server;
svc_release_buffer(rqstp);
kfree(rqstp->rq_resp);
kfree(rqstp->rq_argp);
kfree(rqstp->rq_auth_data);
kfree(rqstp);
/* Release the server */
if (serv)
svc_destroy(serv);
}
/*
* Register an RPC service with the local portmapper.
* To unregister a service, call this routine with
* proto and port == 0.
*/
int
svc_register(struct svc_serv *serv, int proto, unsigned short port)
{
struct svc_program *progp;
unsigned long flags;
int i, error = 0, dummy;
progp = serv->sv_program;
dprintk("RPC: svc_register(%s, %s, %d)\n",
progp->pg_name, proto == IPPROTO_UDP? "udp" : "tcp", port);
if (!port)
clear_thread_flag(TIF_SIGPENDING);
for (i = 0; i < progp->pg_nvers; i++) {
if (progp->pg_vers[i] == NULL)
continue;
error = rpc_register(progp->pg_prog, i, proto, port, &dummy);
if (error < 0)
break;
if (port && !dummy) {
error = -EACCES;
break;
}
}
if (!port) {
spin_lock_irqsave(¤t->sighand->siglock, flags);
recalc_sigpending();
spin_unlock_irqrestore(¤t->sighand->siglock, flags);
}
return error;
}
/*
* Process the RPC request.
*/
int
svc_process(struct svc_serv *serv, struct svc_rqst *rqstp)
{
struct svc_program *progp;
struct svc_version *versp = NULL; /* compiler food */
struct svc_procedure *procp = NULL;
struct kvec * argv = &rqstp->rq_arg.head[0];
struct kvec * resv = &rqstp->rq_res.head[0];
kxdrproc_t xdr;
u32 *statp;
u32 dir, prog, vers, proc,
auth_stat, rpc_stat;
int auth_res;
u32 *accept_statp;
rpc_stat = rpc_success;
if (argv->iov_len < 6*4)
goto err_short_len;
/* setup response xdr_buf.
* Initially it has just one page
*/
svc_take_page(rqstp); /* must succeed */
resv->iov_base = page_address(rqstp->rq_respages[0]);
resv->iov_len = 0;
rqstp->rq_res.pages = rqstp->rq_respages+1;
rqstp->rq_res.len = 0;
rqstp->rq_res.page_base = 0;
rqstp->rq_res.page_len = 0;
rqstp->rq_res.buflen = PAGE_SIZE;
rqstp->rq_res.tail[0].iov_len = 0;
/* tcp needs a space for the record length... */
if (rqstp->rq_prot == IPPROTO_TCP)
svc_putu32(resv, 0);
rqstp->rq_xid = svc_getu32(argv);
svc_putu32(resv, rqstp->rq_xid);
dir = ntohl(svc_getu32(argv));
vers = ntohl(svc_getu32(argv));
/* First words of reply: */
svc_putu32(resv, xdr_one); /* REPLY */
if (dir != 0) /* direction != CALL */
goto err_bad_dir;
if (vers != 2) /* RPC version number */
goto err_bad_rpc;
/* Save position in case we later decide to reject: */
accept_statp = resv->iov_base + resv->iov_len;
svc_putu32(resv, xdr_zero); /* ACCEPT */
rqstp->rq_prog = prog = ntohl(svc_getu32(argv)); /* program number */
rqstp->rq_vers = vers = ntohl(svc_getu32(argv)); /* version number */
rqstp->rq_proc = proc = ntohl(svc_getu32(argv)); /* procedure number */
progp = serv->sv_program;
for (progp = serv->sv_program; progp; progp = progp->pg_next)
if (prog == progp->pg_prog)
break;
/*
* Decode auth data, and add verifier to reply buffer.
* We do this before anything else in order to get a decent
* auth verifier.
*/
auth_res = svc_authenticate(rqstp, &auth_stat);
/* Also give the program a chance to reject this call: */
if (auth_res == SVC_OK && progp) {
auth_stat = rpc_autherr_badcred;
auth_res = progp->pg_authenticate(rqstp);
}
switch (auth_res) {
case SVC_OK:
break;
case SVC_GARBAGE:
rpc_stat = rpc_garbage_args;
goto err_bad;
case SVC_SYSERR:
rpc_stat = rpc_system_err;
goto err_bad;
case SVC_DENIED:
goto err_bad_auth;
case SVC_DROP:
goto dropit;
case SVC_COMPLETE:
goto sendit;
}
if (progp == NULL)
goto err_bad_prog;
if (vers >= progp->pg_nvers ||
!(versp = progp->pg_vers[vers]))
goto err_bad_vers;
procp = versp->vs_proc + proc;
if (proc >= versp->vs_nproc || !procp->pc_func)
goto err_bad_proc;
rqstp->rq_server = serv;
rqstp->rq_procinfo = procp;
/* Syntactic check complete */
serv->sv_stats->rpccnt++;
/* Build the reply header. */
statp = resv->iov_base +resv->iov_len;
svc_putu32(resv, rpc_success); /* RPC_SUCCESS */
/* Bump per-procedure stats counter */
procp->pc_count++;
/* Initialize storage for argp and resp */
memset(rqstp->rq_argp, 0, procp->pc_argsize);
memset(rqstp->rq_resp, 0, procp->pc_ressize);
/* un-reserve some of the out-queue now that we have a
* better idea of reply size
*/
if (procp->pc_xdrressize)
svc_reserve(rqstp, procp->pc_xdrressize<<2);
/* Call the function that processes the request. */
if (!versp->vs_dispatch) {
/* Decode arguments */
xdr = procp->pc_decode;
if (xdr && !xdr(rqstp, argv->iov_base, rqstp->rq_argp))
goto err_garbage;
*statp = procp->pc_func(rqstp, rqstp->rq_argp, rqstp->rq_resp);
/* Encode reply */
if (*statp == rpc_success && (xdr = procp->pc_encode)
&& !xdr(rqstp, resv->iov_base+resv->iov_len, rqstp->rq_resp)) {
dprintk("svc: failed to encode reply\n");
/* serv->sv_stats->rpcsystemerr++; */
*statp = rpc_system_err;
}
} else {
dprintk("svc: calling dispatcher\n");
if (!versp->vs_dispatch(rqstp, statp)) {
/* Release reply info */
if (procp->pc_release)
procp->pc_release(rqstp, NULL, rqstp->rq_resp);
goto dropit;
}
}
/* Check RPC status result */
if (*statp != rpc_success)
resv->iov_len = ((void*)statp) - resv->iov_base + 4;
/* Release reply info */
if (procp->pc_release)
procp->pc_release(rqstp, NULL, rqstp->rq_resp);
if (procp->pc_encode == NULL)
goto dropit;
sendit:
if (svc_authorise(rqstp))
goto dropit;
return svc_send(rqstp);
dropit:
svc_authorise(rqstp); /* doesn't hurt to call this twice */
dprintk("svc: svc_process dropit\n");
svc_drop(rqstp);
return 0;
err_short_len:
#ifdef RPC_PARANOIA
printk("svc: short len %Zd, dropping request\n", argv->iov_len);
#endif
goto dropit; /* drop request */
err_bad_dir:
#ifdef RPC_PARANOIA
printk("svc: bad direction %d, dropping request\n", dir);
#endif
serv->sv_stats->rpcbadfmt++;
goto dropit; /* drop request */
err_bad_rpc:
serv->sv_stats->rpcbadfmt++;
svc_putu32(resv, xdr_one); /* REJECT */
svc_putu32(resv, xdr_zero); /* RPC_MISMATCH */
svc_putu32(resv, xdr_two); /* Only RPCv2 supported */
svc_putu32(resv, xdr_two);
goto sendit;
err_bad_auth:
dprintk("svc: authentication failed (%d)\n", ntohl(auth_stat));
serv->sv_stats->rpcbadauth++;
/* Restore write pointer to location of accept status: */
xdr_ressize_check(rqstp, accept_statp);
svc_putu32(resv, xdr_one); /* REJECT */
svc_putu32(resv, xdr_one); /* AUTH_ERROR */
svc_putu32(resv, auth_stat); /* status */
goto sendit;
err_bad_prog:
dprintk("svc: unknown program %d\n", prog);
serv->sv_stats->rpcbadfmt++;
svc_putu32(resv, rpc_prog_unavail);
goto sendit;
err_bad_vers:
#ifdef RPC_PARANOIA
printk("svc: unknown version (%d)\n", vers);
#endif
serv->sv_stats->rpcbadfmt++;
svc_putu32(resv, rpc_prog_mismatch);
svc_putu32(resv, htonl(progp->pg_lovers));
svc_putu32(resv, htonl(progp->pg_hivers));
goto sendit;
err_bad_proc:
#ifdef RPC_PARANOIA
printk("svc: unknown procedure (%d)\n", proc);
#endif
serv->sv_stats->rpcbadfmt++;
svc_putu32(resv, rpc_proc_unavail);
goto sendit;
err_garbage:
#ifdef RPC_PARANOIA
printk("svc: failed to decode args\n");
#endif
rpc_stat = rpc_garbage_args;
err_bad:
serv->sv_stats->rpcbadfmt++;
svc_putu32(resv, rpc_stat);
goto sendit;
}