/*
* Process the RPC request.
*/
int
svc_process(struct svc_rqst *rqstp)
{
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
struct svc_serv *serv = rqstp->rq_server;
u32 dir;
/*
* Setup response xdr_buf.
* Initially it has just one page
*/
rqstp->rq_next_page = &rqstp->rq_respages[1];
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_base = NULL;
rqstp->rq_res.tail[0].iov_len = 0;
dir = svc_getnl(argv);
if (dir != 0) {
/* direction != CALL */
svc_printk(rqstp, "bad direction %d, dropping request\n", dir);
serv->sv_stats->rpcbadfmt++;
goto out_drop;
}
/* Returns 1 for send, 0 for drop */
if (likely(svc_process_common(rqstp, argv, resv))) {
int ret = svc_send(rqstp);
trace_svc_process(rqstp, ret);
return ret;
}
out_drop:
trace_svc_process(rqstp, 0);
svc_drop(rqstp);
return 0;
}
int
svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
{
rpc_authflavor_t flavor;
struct auth_ops *aops;
*authp = rpc_auth_ok;
flavor = svc_getnl(&rqstp->rq_arg.head[0]);
dprintk("svc: svc_authenticate (%d)\n", flavor);
spin_lock(&authtab_lock);
if (flavor >= RPC_AUTH_MAXFLAVOR || !(aops = authtab[flavor])
|| !try_module_get(aops->owner)) {
spin_unlock(&authtab_lock);
*authp = rpc_autherr_badcred;
return SVC_DENIED;
}
spin_unlock(&authtab_lock);
rqstp->rq_authop = aops;
return aops->accept(rqstp, authp);
}
int
svc_authenticate(struct svc_rqst *rqstp, __be32 *authp)
{
rpc_authflavor_t flavor;
struct auth_ops *aops;
*authp = rpc_auth_ok;
flavor = svc_getnl(&rqstp->rq_arg.head[0]);
dprintk("svc: svc_authenticate (%d)\n", flavor);
aops = svc_get_auth_ops(flavor);
if (aops == NULL) {
*authp = rpc_autherr_badcred;
return SVC_DENIED;
}
rqstp->rq_auth_slack = 0;
init_svc_cred(&rqstp->rq_cred);
rqstp->rq_authop = aops;
return aops->accept(rqstp, authp);
}
/*
* Process a backchannel RPC request that arrived over an existing
* outbound connection
*/
int
bc_svc_process(struct svc_serv *serv, struct rpc_rqst *req,
struct svc_rqst *rqstp)
{
struct kvec *argv = &rqstp->rq_arg.head[0];
struct kvec *resv = &rqstp->rq_res.head[0];
struct rpc_task *task;
int proc_error;
int error;
dprintk("svc: %s(%p)\n", __func__, req);
/* Build the svc_rqst used by the common processing routine */
rqstp->rq_xprt = serv->sv_bc_xprt;
rqstp->rq_xid = req->rq_xid;
rqstp->rq_prot = req->rq_xprt->prot;
rqstp->rq_server = serv;
rqstp->rq_addrlen = sizeof(req->rq_xprt->addr);
memcpy(&rqstp->rq_addr, &req->rq_xprt->addr, rqstp->rq_addrlen);
memcpy(&rqstp->rq_arg, &req->rq_rcv_buf, sizeof(rqstp->rq_arg));
memcpy(&rqstp->rq_res, &req->rq_snd_buf, sizeof(rqstp->rq_res));
/* Adjust the argument buffer length */
rqstp->rq_arg.len = req->rq_private_buf.len;
if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len) {
rqstp->rq_arg.head[0].iov_len = rqstp->rq_arg.len;
rqstp->rq_arg.page_len = 0;
} else if (rqstp->rq_arg.len <= rqstp->rq_arg.head[0].iov_len +
rqstp->rq_arg.page_len)
rqstp->rq_arg.page_len = rqstp->rq_arg.len -
rqstp->rq_arg.head[0].iov_len;
else
rqstp->rq_arg.len = rqstp->rq_arg.head[0].iov_len +
rqstp->rq_arg.page_len;
/* reset result send buffer "put" position */
resv->iov_len = 0;
/*
* Skip the next two words because they've already been
* processed in the transport
*/
svc_getu32(argv); /* XID */
svc_getnl(argv); /* CALLDIR */
/* Parse and execute the bc call */
proc_error = svc_process_common(rqstp, argv, resv);
atomic_inc(&req->rq_xprt->bc_free_slots);
if (!proc_error) {
/* Processing error: drop the request */
xprt_free_bc_request(req);
return 0;
}
/* Finally, send the reply synchronously */
memcpy(&req->rq_snd_buf, &rqstp->rq_res, sizeof(req->rq_snd_buf));
task = rpc_run_bc_task(req);
if (IS_ERR(task)) {
error = PTR_ERR(task);
goto out;
}
WARN_ON_ONCE(atomic_read(&task->tk_count) != 1);
error = task->tk_status;
rpc_put_task(task);
out:
dprintk("svc: %s(), error=%d\n", __func__, error);
return error;
}
/*
* Common routine for processing the RPC request.
*/
static int
svc_process_common(struct svc_rqst *rqstp, struct kvec *argv, struct kvec *resv)
{
struct svc_program *progp;
struct svc_version *versp = NULL; /* compiler food */
struct svc_procedure *procp = NULL;
struct svc_serv *serv = rqstp->rq_server;
kxdrproc_t xdr;
__be32 *statp;
u32 prog, vers, proc;
__be32 auth_stat, rpc_stat;
int auth_res;
__be32 *reply_statp;
rpc_stat = rpc_success;
if (argv->iov_len < 6*4)
goto err_short_len;
/* Will be turned off only in gss privacy case: */
set_bit(RQ_SPLICE_OK, &rqstp->rq_flags);
/* Will be turned off only when NFSv4 Sessions are used */
set_bit(RQ_USEDEFERRAL, &rqstp->rq_flags);
clear_bit(RQ_DROPME, &rqstp->rq_flags);
/* Setup reply header */
rqstp->rq_xprt->xpt_ops->xpo_prep_reply_hdr(rqstp);
svc_putu32(resv, rqstp->rq_xid);
vers = svc_getnl(argv);
/* First words of reply: */
svc_putnl(resv, 1); /* REPLY */
if (vers != 2) /* RPC version number */
goto err_bad_rpc;
/* Save position in case we later decide to reject: */
reply_statp = resv->iov_base + resv->iov_len;
svc_putnl(resv, 0); /* ACCEPT */
rqstp->rq_prog = prog = svc_getnl(argv); /* program number */
rqstp->rq_vers = vers = svc_getnl(argv); /* version number */
rqstp->rq_proc = proc = svc_getnl(argv); /* procedure number */
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:
goto err_garbage;
case SVC_SYSERR:
rpc_stat = rpc_system_err;
goto err_bad;
case SVC_DENIED:
goto err_bad_auth;
case SVC_CLOSE:
goto close;
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;
/*
* Some protocol versions (namely NFSv4) require some form of
* congestion control. (See RFC 7530 section 3.1 paragraph 2)
* In other words, UDP is not allowed. We mark those when setting
* up the svc_xprt, and verify that here.
*
* The spec is not very clear about what error should be returned
* when someone tries to access a server that is listening on UDP
* for lower versions. RPC_PROG_MISMATCH seems to be the closest
* fit.
*/
if (versp->vs_need_cong_ctrl &&
!test_bit(XPT_CONG_CTRL, &rqstp->rq_xprt->xpt_flags))
goto err_bad_vers;
procp = versp->vs_proc + proc;
if (proc >= versp->vs_nproc || !procp->pc_func)
goto err_bad_proc;
rqstp->rq_procinfo = procp;
/* Syntactic check complete */
serv->sv_stats->rpccnt++;
/* Build the reply header. */
statp = resv->iov_base +resv->iov_len;
svc_putnl(resv, 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_auth(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_drop_reply ||
test_bit(RQ_DROPME, &rqstp->rq_flags)) {
if (procp->pc_release)
procp->pc_release(rqstp, NULL, rqstp->rq_resp);
goto dropit;
}
if (*statp == rpc_autherr_badcred) {
if (procp->pc_release)
procp->pc_release(rqstp, NULL, rqstp->rq_resp);
goto err_bad_auth;
}
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 close;
return 1; /* Caller can now send it */
dropit:
svc_authorise(rqstp); /* doesn't hurt to call this twice */
dprintk("svc: svc_process dropit\n");
return 0;
close:
if (test_bit(XPT_TEMP, &rqstp->rq_xprt->xpt_flags))
svc_close_xprt(rqstp->rq_xprt);
dprintk("svc: svc_process close\n");
return 0;
err_short_len:
svc_printk(rqstp, "short len %zd, dropping request\n",
argv->iov_len);
goto close;
err_bad_rpc:
serv->sv_stats->rpcbadfmt++;
svc_putnl(resv, 1); /* REJECT */
svc_putnl(resv, 0); /* RPC_MISMATCH */
svc_putnl(resv, 2); /* Only RPCv2 supported */
svc_putnl(resv, 2);
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, reply_statp);
svc_putnl(resv, 1); /* REJECT */
svc_putnl(resv, 1); /* AUTH_ERROR */
svc_putnl(resv, ntohl(auth_stat)); /* status */
goto sendit;
err_bad_prog:
dprintk("svc: unknown program %d\n", prog);
serv->sv_stats->rpcbadfmt++;
svc_putnl(resv, RPC_PROG_UNAVAIL);
goto sendit;
err_bad_vers:
svc_printk(rqstp, "unknown version (%d for prog %d, %s)\n",
vers, prog, progp->pg_name);
serv->sv_stats->rpcbadfmt++;
svc_putnl(resv, RPC_PROG_MISMATCH);
svc_putnl(resv, progp->pg_lovers);
svc_putnl(resv, progp->pg_hivers);
goto sendit;
err_bad_proc:
svc_printk(rqstp, "unknown procedure (%d)\n", proc);
serv->sv_stats->rpcbadfmt++;
svc_putnl(resv, RPC_PROC_UNAVAIL);
goto sendit;
err_garbage:
svc_printk(rqstp, "failed to decode args\n");
rpc_stat = rpc_garbage_args;
err_bad:
serv->sv_stats->rpcbadfmt++;
svc_putnl(resv, ntohl(rpc_stat));
goto sendit;
}