/*
* linux/net/sunrpc/auth_gss/auth_gss.c
*
* RPCSEC_GSS client authentication.
*
* Copyright (c) 2000 The Regents of the University of Michigan.
* All rights reserved.
*
* Dug Song <dugsong@monkey.org>
* Andy Adamson <andros@umich.edu>
*
* Redistribution and use in source and binary forms, with or without
* modification, are permitted provided that the following conditions
* are met:
*
* 1. Redistributions of source code must retain the above copyright
* notice, this list of conditions and the following disclaimer.
* 2. Redistributions in binary form must reproduce the above copyright
* notice, this list of conditions and the following disclaimer in the
* documentation and/or other materials provided with the distribution.
* 3. Neither the name of the University nor the names of its
* contributors may be used to endorse or promote products derived
* from this software without specific prior written permission.
*
* THIS SOFTWARE IS PROVIDED ``AS IS'' AND ANY EXPRESS OR IMPLIED
* WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE
* DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR
* CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF
* SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR
* BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY THEORY OF
* LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT (INCLUDING
* NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF THIS
* SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
*/
#include <linux/module.h>
#include <linux/init.h>
#include <linux/types.h>
#include <linux/slab.h>
#include <linux/sched.h>
#include <linux/pagemap.h>
#include <linux/sunrpc/clnt.h>
#include <linux/sunrpc/auth.h>
#include <linux/sunrpc/auth_gss.h>
#include <linux/sunrpc/svcauth_gss.h>
#include <linux/sunrpc/gss_err.h>
#include <linux/workqueue.h>
#include <linux/sunrpc/rpc_pipe_fs.h>
#include <linux/sunrpc/gss_api.h>
#include <asm/uaccess.h>
#include <linux/hashtable.h>
#include "../netns.h"
static const struct rpc_authops authgss_ops;
static const struct rpc_credops gss_credops;
static const struct rpc_credops gss_nullops;
#define GSS_RETRY_EXPIRED 5
static unsigned int gss_expired_cred_retry_delay = GSS_RETRY_EXPIRED;
#define GSS_KEY_EXPIRE_TIMEO 240
static unsigned int gss_key_expire_timeo = GSS_KEY_EXPIRE_TIMEO;
#if IS_ENABLED(CONFIG_SUNRPC_DEBUG)
# define RPCDBG_FACILITY RPCDBG_AUTH
#endif
#define GSS_CRED_SLACK (RPC_MAX_AUTH_SIZE * 2)
/* length of a krb5 verifier (48), plus data added before arguments when
* using integrity (two 4-byte integers): */
#define GSS_VERF_SLACK 100
static DEFINE_HASHTABLE(gss_auth_hash_table, 4);
static DEFINE_SPINLOCK(gss_auth_hash_lock);
struct gss_pipe {
struct rpc_pipe_dir_object pdo;
struct rpc_pipe *pipe;
struct rpc_clnt *clnt;
const char *name;
struct kref kref;
};
struct gss_auth {
struct kref kref;
struct hlist_node hash;
struct rpc_auth rpc_auth;
struct gss_api_mech *mech;
enum rpc_gss_svc service;
struct rpc_clnt *client;
struct net *net;
/*
* There are two upcall pipes; dentry[1], named "gssd", is used
* for the new text-based upcall; dentry[0] is named after the
* mechanism (for example, "krb5") and exists for
* backwards-compatibility with older gssd's.
*/
struct gss_pipe *gss_pipe[2];
const char *target_name;
};
/* pipe_version >= 0 if and only if someone has a pipe open. */
static DEFINE_SPINLOCK(pipe_version_lock);
static struct rpc_wait_queue pipe_version_rpc_waitqueue;
static DECLARE_WAIT_QUEUE_HEAD(pipe_version_waitqueue);
static void gss_put_auth(struct gss_auth *gss_auth);
static void gss_free_ctx(struct gss_cl_ctx *);
static const struct rpc_pipe_ops gss_upcall_ops_v0;
static const struct rpc_pipe_ops gss_upcall_ops_v1;
static inline struct gss_cl_ctx *
gss_get_ctx(struct gss_cl_ctx *ctx)
{
atomic_inc(&ctx->count);
return ctx;
}
static inline void
gss_put_ctx(struct gss_cl_ctx *ctx)
{
if (atomic_dec_and_test(&ctx->count))
gss_free_ctx(ctx);
}
/* gss_cred_set_ctx:
* called by gss_upcall_callback and gss_create_upcall in order
* to set the gss context. The actual exchange of an old context
* and a new one is protected by the pipe->lock.
*/
static void
gss_cred_set_ctx(struct rpc_cred *cred, struct gss_cl_ctx *ctx)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags))
return;
gss_get_ctx(ctx);
rcu_assign_pointer(gss_cred->gc_ctx, ctx);
set_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
smp_mb__before_atomic();
clear_bit(RPCAUTH_CRED_NEW, &cred->cr_flags);
}
static const void *
simple_get_bytes(const void *p, const void *end, void *res, size_t len)
{
const void *q = (const void *)((const char *)p + len);
if (unlikely(q > end || q < p))
return ERR_PTR(-EFAULT);
memcpy(res, p, len);
return q;
}
static inline const void *
simple_get_netobj(const void *p, const void *end, struct xdr_netobj *dest)
{
const void *q;
unsigned int len;
p = simple_get_bytes(p, end, &len, sizeof(len));
if (IS_ERR(p))
return p;
q = (const void *)((const char *)p + len);
if (unlikely(q > end || q < p))
return ERR_PTR(-EFAULT);
dest->data = kmemdup(p, len, GFP_NOFS);
if (unlikely(dest->data == NULL))
return ERR_PTR(-ENOMEM);
dest->len = len;
return q;
}
static struct gss_cl_ctx *
gss_cred_get_ctx(struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
struct gss_cl_ctx *ctx = NULL;
rcu_read_lock();
ctx = rcu_dereference(gss_cred->gc_ctx);
if (ctx)
gss_get_ctx(ctx);
rcu_read_unlock();
return ctx;
}
static struct gss_cl_ctx *
gss_alloc_context(void)
{
struct gss_cl_ctx *ctx;
ctx = kzalloc(sizeof(*ctx), GFP_NOFS);
if (ctx != NULL) {
ctx->gc_proc = RPC_GSS_PROC_DATA;
ctx->gc_seq = 1; /* NetApp 6.4R1 doesn't accept seq. no. 0 */
spin_lock_init(&ctx->gc_seq_lock);
atomic_set(&ctx->count,1);
}
return ctx;
}
#define GSSD_MIN_TIMEOUT (60 * 60)
static const void *
gss_fill_context(const void *p, const void *end, struct gss_cl_ctx *ctx, struct gss_api_mech *gm)
{
const void *q;
unsigned int seclen;
unsigned int timeout;
unsigned long now = jiffies;
u32 window_size;
int ret;
/* First unsigned int gives the remaining lifetime in seconds of the
* credential - e.g. the remaining TGT lifetime for Kerberos or
* the -t value passed to GSSD.
*/
p = simple_get_bytes(p, end, &timeout, sizeof(timeout));
if (IS_ERR(p))
goto err;
if (timeout == 0)
timeout = GSSD_MIN_TIMEOUT;
ctx->gc_expiry = now + ((unsigned long)timeout * HZ);
/* Sequence number window. Determines the maximum number of
* simultaneous requests
*/
p = simple_get_bytes(p, end, &window_size, sizeof(window_size));
if (IS_ERR(p))
goto err;
ctx->gc_win = window_size;
/* gssd signals an error by passing ctx->gc_win = 0: */
if (ctx->gc_win == 0) {
/*
* in which case, p points to an error code. Anything other
* than -EKEYEXPIRED gets converted to -EACCES.
*/
p = simple_get_bytes(p, end, &ret, sizeof(ret));
if (!IS_ERR(p))
p = (ret == -EKEYEXPIRED) ? ERR_PTR(-EKEYEXPIRED) :
ERR_PTR(-EACCES);
goto err;
}
/* copy the opaque wire context */
p = simple_get_netobj(p, end, &ctx->gc_wire_ctx);
if (IS_ERR(p))
goto err;
/* import the opaque security context */
p = simple_get_bytes(p, end, &seclen, sizeof(seclen));
if (IS_ERR(p))
goto err;
q = (const void *)((const char *)p + seclen);
if (unlikely(q > end || q < p)) {
p = ERR_PTR(-EFAULT);
goto err;
}
ret = gss_import_sec_context(p, seclen, gm, &ctx->gc_gss_ctx, NULL, GFP_NOFS);
if (ret < 0) {
p = ERR_PTR(ret);
goto err;
}
/* is there any trailing data? */
if (q == end) {
p = q;
goto done;
}
/* pull in acceptor name (if there is one) */
p = simple_get_netobj(q, end, &ctx->gc_acceptor);
if (IS_ERR(p))
goto err;
done:
dprintk("RPC: %s Success. gc_expiry %lu now %lu timeout %u acceptor %.*s\n",
__func__, ctx->gc_expiry, now, timeout, ctx->gc_acceptor.len,
ctx->gc_acceptor.data);
return p;
err:
dprintk("RPC: %s returns error %ld\n", __func__, -PTR_ERR(p));
return p;
}
#define UPCALL_BUF_LEN 128
struct gss_upcall_msg {
atomic_t count;
kuid_t uid;
struct rpc_pipe_msg msg;
struct list_head list;
struct gss_auth *auth;
struct rpc_pipe *pipe;
struct rpc_wait_queue rpc_waitqueue;
wait_queue_head_t waitqueue;
struct gss_cl_ctx *ctx;
char databuf[UPCALL_BUF_LEN];
};
static int get_pipe_version(struct net *net)
{
struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
int ret;
spin_lock(&pipe_version_lock);
if (sn->pipe_version >= 0) {
atomic_inc(&sn->pipe_users);
ret = sn->pipe_version;
} else
ret = -EAGAIN;
spin_unlock(&pipe_version_lock);
return ret;
}
static void put_pipe_version(struct net *net)
{
struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
if (atomic_dec_and_lock(&sn->pipe_users, &pipe_version_lock)) {
sn->pipe_version = -1;
spin_unlock(&pipe_version_lock);
}
}
static void
gss_release_msg(struct gss_upcall_msg *gss_msg)
{
struct net *net = gss_msg->auth->net;
if (!atomic_dec_and_test(&gss_msg->count))
return;
put_pipe_version(net);
BUG_ON(!list_empty(&gss_msg->list));
if (gss_msg->ctx != NULL)
gss_put_ctx(gss_msg->ctx);
rpc_destroy_wait_queue(&gss_msg->rpc_waitqueue);
gss_put_auth(gss_msg->auth);
kfree(gss_msg);
}
static struct gss_upcall_msg *
__gss_find_upcall(struct rpc_pipe *pipe, kuid_t uid)
{
struct gss_upcall_msg *pos;
list_for_each_entry(pos, &pipe->in_downcall, list) {
if (!uid_eq(pos->uid, uid))
continue;
atomic_inc(&pos->count);
dprintk("RPC: %s found msg %p\n", __func__, pos);
return pos;
}
dprintk("RPC: %s found nothing\n", __func__);
return NULL;
}
/* Try to add an upcall to the pipefs queue.
* If an upcall owned by our uid already exists, then we return a reference
* to that upcall instead of adding the new upcall.
*/
static inline struct gss_upcall_msg *
gss_add_msg(struct gss_upcall_msg *gss_msg)
{
struct rpc_pipe *pipe = gss_msg->pipe;
struct gss_upcall_msg *old;
spin_lock(&pipe->lock);
old = __gss_find_upcall(pipe, gss_msg->uid);
if (old == NULL) {
atomic_inc(&gss_msg->count);
list_add(&gss_msg->list, &pipe->in_downcall);
} else
gss_msg = old;
spin_unlock(&pipe->lock);
return gss_msg;
}
static void
__gss_unhash_msg(struct gss_upcall_msg *gss_msg)
{
list_del_init(&gss_msg->list);
rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
wake_up_all(&gss_msg->waitqueue);
atomic_dec(&gss_msg->count);
}
static void
gss_unhash_msg(struct gss_upcall_msg *gss_msg)
{
struct rpc_pipe *pipe = gss_msg->pipe;
if (list_empty(&gss_msg->list))
return;
spin_lock(&pipe->lock);
if (!list_empty(&gss_msg->list))
__gss_unhash_msg(gss_msg);
spin_unlock(&pipe->lock);
}
static void
gss_handle_downcall_result(struct gss_cred *gss_cred, struct gss_upcall_msg *gss_msg)
{
switch (gss_msg->msg.errno) {
case 0:
if (gss_msg->ctx == NULL)
break;
clear_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
gss_cred_set_ctx(&gss_cred->gc_base, gss_msg->ctx);
break;
case -EKEYEXPIRED:
set_bit(RPCAUTH_CRED_NEGATIVE, &gss_cred->gc_base.cr_flags);
}
gss_cred->gc_upcall_timestamp = jiffies;
gss_cred->gc_upcall = NULL;
rpc_wake_up_status(&gss_msg->rpc_waitqueue, gss_msg->msg.errno);
}
static void
gss_upcall_callback(struct rpc_task *task)
{
struct gss_cred *gss_cred = container_of(task->tk_rqstp->rq_cred,
struct gss_cred, gc_base);
struct gss_upcall_msg *gss_msg = gss_cred->gc_upcall;
struct rpc_pipe *pipe = gss_msg->pipe;
spin_lock(&pipe->lock);
gss_handle_downcall_result(gss_cred, gss_msg);
spin_unlock(&pipe->lock);
task->tk_status = gss_msg->msg.errno;
gss_release_msg(gss_msg);
}
static void gss_encode_v0_msg(struct gss_upcall_msg *gss_msg)
{
uid_t uid = from_kuid(&init_user_ns, gss_msg->uid);
memcpy(gss_msg->databuf, &uid, sizeof(uid));
gss_msg->msg.data = gss_msg->databuf;
gss_msg->msg.len = sizeof(uid);
BUILD_BUG_ON(sizeof(uid) > sizeof(gss_msg->databuf));
}
static int gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
const char *service_name,
const char *target_name)
{
struct gss_api_mech *mech = gss_msg->auth->mech;
char *p = gss_msg->databuf;
size_t buflen = sizeof(gss_msg->databuf);
int len;
len = scnprintf(p, buflen, "mech=%s uid=%d ", mech->gm_name,
from_kuid(&init_user_ns, gss_msg->uid));
buflen -= len;
p += len;
gss_msg->msg.len = len;
if (target_name) {
len = scnprintf(p, buflen, "target=%s ", target_name);
buflen -= len;
p += len;
gss_msg->msg.len += len;
}
if (service_name != NULL) {
len = scnprintf(p, buflen, "service=%s ", service_name);
buflen -= len;
p += len;
gss_msg->msg.len += len;
}
if (mech->gm_upcall_enctypes) {
len = scnprintf(p, buflen, "enctypes=%s ",
mech->gm_upcall_enctypes);
buflen -= len;
p += len;
gss_msg->msg.len += len;
}
len = scnprintf(p, buflen, "\n");
if (len == 0)
goto out_overflow;
gss_msg->msg.len += len;
gss_msg->msg.data = gss_msg->databuf;
return 0;
out_overflow:
WARN_ON_ONCE(1);
return -ENOMEM;
}
static struct gss_upcall_msg *
gss_alloc_msg(struct gss_auth *gss_auth,
kuid_t uid, const char *service_name)
{
struct gss_upcall_msg *gss_msg;
int vers;
int err = -ENOMEM;
gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
if (gss_msg == NULL)
goto err;
vers = get_pipe_version(gss_auth->net);
err = vers;
if (err < 0)
goto err_free_msg;
gss_msg->pipe = gss_auth->gss_pipe[vers]->pipe;
INIT_LIST_HEAD(&gss_msg->list);
rpc_init_wait_queue(&gss_msg->rpc_waitqueue, "RPCSEC_GSS upcall waitq");
init_waitqueue_head(&gss_msg->waitqueue);
atomic_set(&gss_msg->count, 1);
gss_msg->uid = uid;
gss_msg->auth = gss_auth;
switch (vers) {
case 0:
gss_encode_v0_msg(gss_msg);
break;
default:
err = gss_encode_v1_msg(gss_msg, service_name, gss_auth->target_name);
if (err)
goto err_put_pipe_version;
};
kref_get(&gss_auth->kref);
return gss_msg;
err_put_pipe_version:
put_pipe_version(gss_auth->net);
err_free_msg:
kfree(gss_msg);
err:
return ERR_PTR(err);
}
static struct gss_upcall_msg *
gss_setup_upcall(struct gss_auth *gss_auth, struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred,
struct gss_cred, gc_base);
struct gss_upcall_msg *gss_new, *gss_msg;
kuid_t uid = cred->cr_uid;
gss_new = gss_alloc_msg(gss_auth, uid, gss_cred->gc_principal);
if (IS_ERR(gss_new))
return gss_new;
gss_msg = gss_add_msg(gss_new);
if (gss_msg == gss_new) {
int res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg);
if (res) {
gss_unhash_msg(gss_new);
gss_msg = ERR_PTR(res);
}
} else
gss_release_msg(gss_new);
return gss_msg;
}
static void warn_gssd(void)
{
dprintk("AUTH_GSS upcall failed. Please check user daemon is running.\n");
}
static inline int
gss_refresh_upcall(struct rpc_task *task)
{
struct rpc_cred *cred = task->tk_rqstp->rq_cred;
struct gss_auth *gss_auth = container_of(cred->cr_auth,
struct gss_auth, rpc_auth);
struct gss_cred *gss_cred = container_of(cred,
struct gss_cred, gc_base);
struct gss_upcall_msg *gss_msg;
struct rpc_pipe *pipe;
int err = 0;
dprintk("RPC: %5u %s for uid %u\n",
task->tk_pid, __func__, from_kuid(&init_user_ns, cred->cr_uid));
gss_msg = gss_setup_upcall(gss_auth, cred);
if (PTR_ERR(gss_msg) == -EAGAIN) {
/* XXX: warning on the first, under the assumption we
* shouldn't normally hit this case on a refresh. */
warn_gssd();
task->tk_timeout = 15*HZ;
rpc_sleep_on(&pipe_version_rpc_waitqueue, task, NULL);
return -EAGAIN;
}
if (IS_ERR(gss_msg)) {
err = PTR_ERR(gss_msg);
goto out;
}
pipe = gss_msg->pipe;
spin_lock(&pipe->lock);
if (gss_cred->gc_upcall != NULL)
rpc_sleep_on(&gss_cred->gc_upcall->rpc_waitqueue, task, NULL);
else if (gss_msg->ctx == NULL && gss_msg->msg.errno >= 0) {
task->tk_timeout = 0;
gss_cred->gc_upcall = gss_msg;
/* gss_upcall_callback will release the reference to gss_upcall_msg */
atomic_inc(&gss_msg->count);
rpc_sleep_on(&gss_msg->rpc_waitqueue, task, gss_upcall_callback);
} else {
gss_handle_downcall_result(gss_cred, gss_msg);
err = gss_msg->msg.errno;
}
spin_unlock(&pipe->lock);
gss_release_msg(gss_msg);
out:
dprintk("RPC: %5u %s for uid %u result %d\n",
task->tk_pid, __func__,
from_kuid(&init_user_ns, cred->cr_uid), err);
return err;
}
static inline int
gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
{
struct net *net = gss_auth->net;
struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
struct rpc_pipe *pipe;
struct rpc_cred *cred = &gss_cred->gc_base;
struct gss_upcall_msg *gss_msg;
DEFINE_WAIT(wait);
int err;
dprintk("RPC: %s for uid %u\n",
__func__, from_kuid(&init_user_ns, cred->cr_uid));
retry:
err = 0;
/* if gssd is down, just skip upcalling altogether */
if (!gssd_running(net)) {
warn_gssd();
return -EACCES;
}
gss_msg = gss_setup_upcall(gss_auth, cred);
if (PTR_ERR(gss_msg) == -EAGAIN) {
err = wait_event_interruptible_timeout(pipe_version_waitqueue,
sn->pipe_version >= 0, 15 * HZ);
if (sn->pipe_version < 0) {
warn_gssd();
err = -EACCES;
}
if (err < 0)
goto out;
goto retry;
}
if (IS_ERR(gss_msg)) {
err = PTR_ERR(gss_msg);
goto out;
}
pipe = gss_msg->pipe;
for (;;) {
prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_KILLABLE);
spin_lock(&pipe->lock);
if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) {
break;
}
spin_unlock(&pipe->lock);
if (fatal_signal_pending(current)) {
err = -ERESTARTSYS;
goto out_intr;
}
schedule();
}
if (gss_msg->ctx)
gss_cred_set_ctx(cred, gss_msg->ctx);
else
err = gss_msg->msg.errno;
spin_unlock(&pipe->lock);
out_intr:
finish_wait(&gss_msg->waitqueue, &wait);
gss_release_msg(gss_msg);
out:
dprintk("RPC: %s for uid %u result %d\n",
__func__, from_kuid(&init_user_ns, cred->cr_uid), err);
return err;
}
#define MSG_BUF_MAXSIZE 1024
static ssize_t
gss_pipe_downcall(struct file *filp, const char __user *src, size_t mlen)
{
const void *p, *end;
void *buf;
struct gss_upcall_msg *gss_msg;
struct rpc_pipe *pipe = RPC_I(file_inode(filp))->pipe;
struct gss_cl_ctx *ctx;
uid_t id;
kuid_t uid;
ssize_t err = -EFBIG;
if (mlen > MSG_BUF_MAXSIZE)
goto out;
err = -ENOMEM;
buf = kmalloc(mlen, GFP_NOFS);
if (!buf)
goto out;
err = -EFAULT;
if (copy_from_user(buf, src, mlen))
goto err;
end = (const void *)((char *)buf + mlen);
p = simple_get_bytes(buf, end, &id, sizeof(id));
if (IS_ERR(p)) {
err = PTR_ERR(p);
goto err;
}
uid = make_kuid(&init_user_ns, id);
if (!uid_valid(uid)) {
err = -EINVAL;
goto err;
}
err = -ENOMEM;
ctx = gss_alloc_context();
if (ctx == NULL)
goto err;
err = -ENOENT;
/* Find a matching upcall */
spin_lock(&pipe->lock);
gss_msg = __gss_find_upcall(pipe, uid);
if (gss_msg == NULL) {
spin_unlock(&pipe->lock);
goto err_put_ctx;
}
list_del_init(&gss_msg->list);
spin_unlock(&pipe->lock);
p = gss_fill_context(p, end, ctx, gss_msg->auth->mech);
if (IS_ERR(p)) {
err = PTR_ERR(p);
switch (err) {
case -EACCES:
case -EKEYEXPIRED:
gss_msg->msg.errno = err;
err = mlen;
break;
case -EFAULT:
case -ENOMEM:
case -EINVAL:
case -ENOSYS:
gss_msg->msg.errno = -EAGAIN;
break;
default:
printk(KERN_CRIT "%s: bad return from "
"gss_fill_context: %zd\n", __func__, err);
BUG();
}
goto err_release_msg;
}
gss_msg->ctx = gss_get_ctx(ctx);
err = mlen;
err_release_msg:
spin_lock(&pipe->lock);
__gss_unhash_msg(gss_msg);
spin_unlock(&pipe->lock);
gss_release_msg(gss_msg);
err_put_ctx:
gss_put_ctx(ctx);
err:
kfree(buf);
out:
dprintk("RPC: %s returning %Zd\n", __func__, err);
return err;
}
static int gss_pipe_open(struct inode *inode, int new_version)
{
struct net *net = inode->i_sb->s_fs_info;
struct sunrpc_net *sn = net_generic(net, sunrpc_net_id);
int ret = 0;
spin_lock(&pipe_version_lock);
if (sn->pipe_version < 0) {
/* First open of any gss pipe determines the version: */
sn->pipe_version = new_version;
rpc_wake_up(&pipe_version_rpc_waitqueue);
wake_up(&pipe_version_waitqueue);
} else if (sn->pipe_version != new_version) {
/* Trying to open a pipe of a different version */
ret = -EBUSY;
goto out;
}
atomic_inc(&sn->pipe_users);
out:
spin_unlock(&pipe_version_lock);
return ret;
}
static int gss_pipe_open_v0(struct inode *inode)
{
return gss_pipe_open(inode, 0);
}
static int gss_pipe_open_v1(struct inode *inode)
{
return gss_pipe_open(inode, 1);
}
static void
gss_pipe_release(struct inode *inode)
{
struct net *net = inode->i_sb->s_fs_info;
struct rpc_pipe *pipe = RPC_I(inode)->pipe;
struct gss_upcall_msg *gss_msg;
restart:
spin_lock(&pipe->lock);
list_for_each_entry(gss_msg, &pipe->in_downcall, list) {
if (!list_empty(&gss_msg->msg.list))
continue;
gss_msg->msg.errno = -EPIPE;
atomic_inc(&gss_msg->count);
__gss_unhash_msg(gss_msg);
spin_unlock(&pipe->lock);
gss_release_msg(gss_msg);
goto restart;
}
spin_unlock(&pipe->lock);
put_pipe_version(net);
}
static void
gss_pipe_destroy_msg(struct rpc_pipe_msg *msg)
{
struct gss_upcall_msg *gss_msg = container_of(msg, struct gss_upcall_msg, msg);
if (msg->errno < 0) {
dprintk("RPC: %s releasing msg %p\n",
__func__, gss_msg);
atomic_inc(&gss_msg->count);
gss_unhash_msg(gss_msg);
if (msg->errno == -ETIMEDOUT)
warn_gssd();
gss_release_msg(gss_msg);
}
}
static void gss_pipe_dentry_destroy(struct dentry *dir,
struct rpc_pipe_dir_object *pdo)
{
struct gss_pipe *gss_pipe = pdo->pdo_data;
struct rpc_pipe *pipe = gss_pipe->pipe;
if (pipe->dentry != NULL) {
rpc_unlink(pipe->dentry);
pipe->dentry = NULL;
}
}
static int gss_pipe_dentry_create(struct dentry *dir,
struct rpc_pipe_dir_object *pdo)
{
struct gss_pipe *p = pdo->pdo_data;
struct dentry *dentry;
dentry = rpc_mkpipe_dentry(dir, p->name, p->clnt, p->pipe);
if (IS_ERR(dentry))
return PTR_ERR(dentry);
p->pipe->dentry = dentry;
return 0;
}
static const struct rpc_pipe_dir_object_ops gss_pipe_dir_object_ops = {
.create = gss_pipe_dentry_create,
.destroy = gss_pipe_dentry_destroy,
};
static struct gss_pipe *gss_pipe_alloc(struct rpc_clnt *clnt,
const char *name,
const struct rpc_pipe_ops *upcall_ops)
{
struct gss_pipe *p;
int err = -ENOMEM;
p = kmalloc(sizeof(*p), GFP_KERNEL);
if (p == NULL)
goto err;
p->pipe = rpc_mkpipe_data(upcall_ops, RPC_PIPE_WAIT_FOR_OPEN);
if (IS_ERR(p->pipe)) {
err = PTR_ERR(p->pipe);
goto err_free_gss_pipe;
}
p->name = name;
p->clnt = clnt;
kref_init(&p->kref);
rpc_init_pipe_dir_object(&p->pdo,
&gss_pipe_dir_object_ops,
p);
return p;
err_free_gss_pipe:
kfree(p);
err:
return ERR_PTR(err);
}
struct gss_alloc_pdo {
struct rpc_clnt *clnt;
const char *name;
const struct rpc_pipe_ops *upcall_ops;
};
static int gss_pipe_match_pdo(struct rpc_pipe_dir_object *pdo, void *data)
{
struct gss_pipe *gss_pipe;
struct gss_alloc_pdo *args = data;
if (pdo->pdo_ops != &gss_pipe_dir_object_ops)
return 0;
gss_pipe = container_of(pdo, struct gss_pipe, pdo);
if (strcmp(gss_pipe->name, args->name) != 0)
return 0;
if (!kref_get_unless_zero(&gss_pipe->kref))
return 0;
return 1;
}
static struct rpc_pipe_dir_object *gss_pipe_alloc_pdo(void *data)
{
struct gss_pipe *gss_pipe;
struct gss_alloc_pdo *args = data;
gss_pipe = gss_pipe_alloc(args->clnt, args->name, args->upcall_ops);
if (!IS_ERR(gss_pipe))
return &gss_pipe->pdo;
return NULL;
}
static struct gss_pipe *gss_pipe_get(struct rpc_clnt *clnt,
const char *name,
const struct rpc_pipe_ops *upcall_ops)
{
struct net *net = rpc_net_ns(clnt);
struct rpc_pipe_dir_object *pdo;
struct gss_alloc_pdo args = {
.clnt = clnt,
.name = name,
.upcall_ops = upcall_ops,
};
pdo = rpc_find_or_alloc_pipe_dir_object(net,
&clnt->cl_pipedir_objects,
gss_pipe_match_pdo,
gss_pipe_alloc_pdo,
&args);
if (pdo != NULL)
return container_of(pdo, struct gss_pipe, pdo);
return ERR_PTR(-ENOMEM);
}
static void __gss_pipe_free(struct gss_pipe *p)
{
struct rpc_clnt *clnt = p->clnt;
struct net *net = rpc_net_ns(clnt);
rpc_remove_pipe_dir_object(net,
&clnt->cl_pipedir_objects,
&p->pdo);
rpc_destroy_pipe_data(p->pipe);
kfree(p);
}
static void __gss_pipe_release(struct kref *kref)
{
struct gss_pipe *p = container_of(kref, struct gss_pipe, kref);
__gss_pipe_free(p);
}
static void gss_pipe_free(struct gss_pipe *p)
{
if (p != NULL)
kref_put(&p->kref, __gss_pipe_release);
}
/*
* NOTE: we have the opportunity to use different
* parameters based on the input flavor (which must be a pseudoflavor)
*/
static struct gss_auth *
gss_create_new(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
{
rpc_authflavor_t flavor = args->pseudoflavor;
struct gss_auth *gss_auth;
struct gss_pipe *gss_pipe;
struct rpc_auth * auth;
int err = -ENOMEM; /* XXX? */
dprintk("RPC: creating GSS authenticator for client %p\n", clnt);
if (!try_module_get(THIS_MODULE))
return ERR_PTR(err);
if (!(gss_auth = kmalloc(sizeof(*gss_auth), GFP_KERNEL)))
goto out_dec;
INIT_HLIST_NODE(&gss_auth->hash);
gss_auth->target_name = NULL;
if (args->target_name) {
gss_auth->target_name = kstrdup(args->target_name, GFP_KERNEL);
if (gss_auth->target_name == NULL)
goto err_free;
}
gss_auth->client = clnt;
gss_auth->net = get_net(rpc_net_ns(clnt));
err = -EINVAL;
gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor);
if (!gss_auth->mech) {
dprintk("RPC: Pseudoflavor %d not found!\n", flavor);
goto err_put_net;
}
gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
if (gss_auth->service == 0)
goto err_put_mech;
if (!gssd_running(gss_auth->net))
goto err_put_mech;
auth = &gss_auth->rpc_auth;
auth->au_cslack = GSS_CRED_SLACK >> 2;
auth->au_rslack = GSS_VERF_SLACK >> 2;
auth->au_ops = &authgss_ops;
auth->au_flavor = flavor;
atomic_set(&auth->au_count, 1);
kref_init(&gss_auth->kref);
err = rpcauth_init_credcache(auth);
if (err)
goto err_put_mech;
/*
* Note: if we created the old pipe first, then someone who
* examined the directory at the right moment might conclude
* that we supported only the old pipe. So we instead create
* the new pipe first.
*/
gss_pipe = gss_pipe_get(clnt, "gssd", &gss_upcall_ops_v1);
if (IS_ERR(gss_pipe)) {
err = PTR_ERR(gss_pipe);
goto err_destroy_credcache;
}
gss_auth->gss_pipe[1] = gss_pipe;
gss_pipe = gss_pipe_get(clnt, gss_auth->mech->gm_name,
&gss_upcall_ops_v0);
if (IS_ERR(gss_pipe)) {
err = PTR_ERR(gss_pipe);
goto err_destroy_pipe_1;
}
gss_auth->gss_pipe[0] = gss_pipe;
return gss_auth;
err_destroy_pipe_1:
gss_pipe_free(gss_auth->gss_pipe[1]);
err_destroy_credcache:
rpcauth_destroy_credcache(auth);
err_put_mech:
gss_mech_put(gss_auth->mech);
err_put_net:
put_net(gss_auth->net);
err_free:
kfree(gss_auth->target_name);
kfree(gss_auth);
out_dec:
module_put(THIS_MODULE);
return ERR_PTR(err);
}
static void
gss_free(struct gss_auth *gss_auth)
{
gss_pipe_free(gss_auth->gss_pipe[0]);
gss_pipe_free(gss_auth->gss_pipe[1]);
gss_mech_put(gss_auth->mech);
put_net(gss_auth->net);
kfree(gss_auth->target_name);
kfree(gss_auth);
module_put(THIS_MODULE);
}
static void
gss_free_callback(struct kref *kref)
{
struct gss_auth *gss_auth = container_of(kref, struct gss_auth, kref);
gss_free(gss_auth);
}
static void
gss_put_auth(struct gss_auth *gss_auth)
{
kref_put(&gss_auth->kref, gss_free_callback);
}
static void
gss_destroy(struct rpc_auth *auth)
{
struct gss_auth *gss_auth = container_of(auth,
struct gss_auth, rpc_auth);
dprintk("RPC: destroying GSS authenticator %p flavor %d\n",
auth, auth->au_flavor);
if (hash_hashed(&gss_auth->hash)) {
spin_lock(&gss_auth_hash_lock);
hash_del(&gss_auth->hash);
spin_unlock(&gss_auth_hash_lock);
}
gss_pipe_free(gss_auth->gss_pipe[0]);
gss_auth->gss_pipe[0] = NULL;
gss_pipe_free(gss_auth->gss_pipe[1]);
gss_auth->gss_pipe[1] = NULL;
rpcauth_destroy_credcache(auth);
gss_put_auth(gss_auth);
}
/*
* Auths may be shared between rpc clients that were cloned from a
* common client with the same xprt, if they also share the flavor and
* target_name.
*
* The auth is looked up from the oldest parent sharing the same
* cl_xprt, and the auth itself references only that common parent
* (which is guaranteed to last as long as any of its descendants).
*/
static struct gss_auth *
gss_auth_find_or_add_hashed(struct rpc_auth_create_args *args,
struct rpc_clnt *clnt,
struct gss_auth *new)
{
struct gss_auth *gss_auth;
unsigned long hashval = (unsigned long)clnt;
spin_lock(&gss_auth_hash_lock);
hash_for_each_possible(gss_auth_hash_table,
gss_auth,
hash,
hashval) {
if (gss_auth->client != clnt)
continue;
if (gss_auth->rpc_auth.au_flavor != args->pseudoflavor)
continue;
if (gss_auth->target_name != args->target_name) {
if (gss_auth->target_name == NULL)
continue;
if (args->target_name == NULL)
continue;
if (strcmp(gss_auth->target_name, args->target_name))
continue;
}
if (!atomic_inc_not_zero(&gss_auth->rpc_auth.au_count))
continue;
goto out;
}
if (new)
hash_add(gss_auth_hash_table, &new->hash, hashval);
gss_auth = new;
out:
spin_unlock(&gss_auth_hash_lock);
return gss_auth;
}
static struct gss_auth *
gss_create_hashed(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
{
struct gss_auth *gss_auth;
struct gss_auth *new;
gss_auth = gss_auth_find_or_add_hashed(args, clnt, NULL);
if (gss_auth != NULL)
goto out;
new = gss_create_new(args, clnt);
if (IS_ERR(new))
return new;
gss_auth = gss_auth_find_or_add_hashed(args, clnt, new);
if (gss_auth != new)
gss_destroy(&new->rpc_auth);
out:
return gss_auth;
}
static struct rpc_auth *
gss_create(struct rpc_auth_create_args *args, struct rpc_clnt *clnt)
{
struct gss_auth *gss_auth;
struct rpc_xprt *xprt = rcu_access_pointer(clnt->cl_xprt);
while (clnt != clnt->cl_parent) {
struct rpc_clnt *parent = clnt->cl_parent;
/* Find the original parent for this transport */
if (rcu_access_pointer(parent->cl_xprt) != xprt)
break;
clnt = parent;
}
gss_auth = gss_create_hashed(args, clnt);
if (IS_ERR(gss_auth))
return ERR_CAST(gss_auth);
return &gss_auth->rpc_auth;
}
/*
* gss_destroying_context will cause the RPCSEC_GSS to send a NULL RPC call
* to the server with the GSS control procedure field set to
* RPC_GSS_PROC_DESTROY. This should normally cause the server to release
* all RPCSEC_GSS state associated with that context.
*/
static int
gss_destroying_context(struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
struct gss_cl_ctx *ctx = rcu_dereference_protected(gss_cred->gc_ctx, 1);
struct rpc_task *task;
if (test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0)
return 0;
ctx->gc_proc = RPC_GSS_PROC_DESTROY;
cred->cr_ops = &gss_nullops;
/* Take a reference to ensure the cred will be destroyed either
* by the RPC call or by the put_rpccred() below */
get_rpccred(cred);
task = rpc_call_null(gss_auth->client, cred, RPC_TASK_ASYNC|RPC_TASK_SOFT);
if (!IS_ERR(task))
rpc_put_task(task);
put_rpccred(cred);
return 1;
}
/* gss_destroy_cred (and gss_free_ctx) are used to clean up after failure
* to create a new cred or context, so they check that things have been
* allocated before freeing them. */
static void
gss_do_free_ctx(struct gss_cl_ctx *ctx)
{
dprintk("RPC: %s\n", __func__);
gss_delete_sec_context(&ctx->gc_gss_ctx);
kfree(ctx->gc_wire_ctx.data);
kfree(ctx->gc_acceptor.data);
kfree(ctx);
}
static void
gss_free_ctx_callback(struct rcu_head *head)
{
struct gss_cl_ctx *ctx = container_of(head, struct gss_cl_ctx, gc_rcu);
gss_do_free_ctx(ctx);
}
static void
gss_free_ctx(struct gss_cl_ctx *ctx)
{
call_rcu(&ctx->gc_rcu, gss_free_ctx_callback);
}
static void
gss_free_cred(struct gss_cred *gss_cred)
{
dprintk("RPC: %s cred=%p\n", __func__, gss_cred);
kfree(gss_cred);
}
static void
gss_free_cred_callback(struct rcu_head *head)
{
struct gss_cred *gss_cred = container_of(head, struct gss_cred, gc_base.cr_rcu);
gss_free_cred(gss_cred);
}
static void
gss_destroy_nullcred(struct rpc_cred *cred)
{
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
struct gss_auth *gss_auth = container_of(cred->cr_auth, struct gss_auth, rpc_auth);
struct gss_cl_ctx *ctx = rcu_dereference_protected(gss_cred->gc_ctx, 1);
RCU_INIT_POINTER(gss_cred->gc_ctx, NULL);
call_rcu(&cred->cr_rcu, gss_free_cred_callback);
if (ctx)
gss_put_ctx(ctx);
gss_put_auth(gss_auth);
}
static void
gss_destroy_cred(struct rpc_cred *cred)
{
if (gss_destroying_context(cred))
return;
gss_destroy_nullcred(cred);
}
/*
* Lookup RPCSEC_GSS cred for the current process
*/
static struct rpc_cred *
gss_lookup_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
return rpcauth_lookup_credcache(auth, acred, flags);
}
static struct rpc_cred *
gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags)
{
struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
struct gss_cred *cred = NULL;
int err = -ENOMEM;
dprintk("RPC: %s for uid %d, flavor %d\n",
__func__, from_kuid(&init_user_ns, acred->uid),
auth->au_flavor);
if (!(cred = kzalloc(sizeof(*cred), GFP_NOFS)))
goto out_err;
rpcauth_init_cred(&cred->gc_base, acred, auth, &gss_credops);
/*
* Note: in order to force a call to call_refresh(), we deliberately
* fail to flag the credential as RPCAUTH_CRED_UPTODATE.
*/
cred->gc_base.cr_flags = 1UL << RPCAUTH_CRED_NEW;
cred->gc_service = gss_auth->service;
cred->gc_principal = NULL;
if (acred->machine_cred)
cred->gc_principal = acred->principal;
kref_get(&gss_auth->kref);
return &cred->gc_base;
out_err:
dprintk("RPC: %s failed with error %d\n", __func__, err);
return ERR_PTR(err);
}
static int
gss_cred_init(struct rpc_auth *auth, struct rpc_cred *cred)
{
struct gss_auth *gss_auth = container_of(auth, struct gss_auth, rpc_auth);
struct gss_cred *gss_cred = container_of(cred,struct gss_cred, gc_base);
int err;
do {
err = gss_create_upcall(gss_auth, gss_cred);
} while (err == -EAGAIN);
return err;
}
static char *
gss_stringify_acceptor(struct rpc_cred *cred)
{
char *string = NULL;
struct gss_cred *gss_cred = container_of(cred, struct gss_cred, gc_base);
struct gss_cl_ctx *ctx;
unsigned int len;
struct xdr_netobj *acceptor;
rcu_read_lock();
ctx = rcu_dereference(gss_cred->gc_ctx);
if (!ctx)
goto out;
len = ctx->gc_acceptor.len;
rcu_read_unlock();
/* no point if there's no string */
if (!len)
return NULL;
realloc:
string = kmalloc(len + 1, GFP_KERNEL);
if (!string)
return NULL;
rcu_read_lock();
ctx = rcu_dereference(gss_cred->gc_ctx);
/* did the ctx disappear or was it replaced by one with no acceptor? */
if (!ctx || !ctx->gc_acceptor.len) {
kfree(string);
string = NULL;
goto out;
}
acceptor = &ctx->gc_acceptor;
/*
* Did we find a new acceptor that's longer than the original? Allocate
* a longer buffer and try again.
*/
if (len < acceptor->len) {
len = acceptor->len;
rcu_read_unlock();
kfree(string);
goto realloc;
}
memcpy(string, acceptor->data, acceptor->len);
string[acceptor->len] = '\0';
out:
rcu_read_unlock();
return string;
}
/*
* Returns -EACCES if GSS context is NULL or will expire within the
* timeout (miliseconds)
*/
static int
gss_key_timeout(struct rpc_cred *rc)
{
struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
struct gss_cl_ctx *ctx;
unsigned long timeout = jiffies + (gss_key_expire_timeo * HZ);
int ret = 0;
rcu_read_lock();
ctx = rcu_dereference(gss_cred->gc_ctx);
if (!ctx || time_after(timeout, ctx->gc_expiry))
ret = -EACCES;
rcu_read_unlock();
return ret;
}
static int
gss_match(struct auth_cred *acred, struct rpc_cred *rc, int flags)
{
struct gss_cred *gss_cred = container_of(rc, struct gss_cred, gc_base);
struct gss_cl_ctx *ctx;
int ret;
if (test_bit(RPCAUTH_CRED_NEW, &rc->cr_flags))
goto out;
/* Don't match with creds that have expired. */
rcu_read_lock();
ctx = rcu_dereference(gss_cred->gc_ctx);
if (!ctx || time_after(jiffies, ctx->gc_expiry)) {
rcu_read_unlock();
return 0;
}
rcu_read_unlock();
if (!test_bit(RPCAUTH_CRED_UPTODATE, &rc->cr_flags))
return 0;
out:
if (acred->principal != NULL) {
if (gss_cred->gc_principal == NULL)
return 0;
ret = strcmp(acred->principal, gss_cred->gc_principal) == 0;
goto check_expire;
}
if (gss_cred->gc_principal != NULL)
return 0;
ret = uid_eq(rc->cr_uid, acred->uid);
check_expire:
if (ret == 0)
return ret;
/* Notify acred users of GSS context expiration timeout */
if (test_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags) &&
(gss_key_timeout(rc) != 0)) {
/* test will now be done from generic cred */
test_and_clear_bit(RPC_CRED_NOTIFY_TIMEOUT, &acred->ac_flags);
/* tell NFS layer that key will expire soon */
set_bit(RPC_CRED_KEY_EXPIRE_SOON, &acred->ac_flags);
}
return ret;
}
/*
* Marshal credentials.
* Maybe we should keep a cached credential for performance reasons.
*/
static __be32 *
gss_marshal(struct rpc_task *task, __be32 *p)
{
struct rpc_rqst *req = task->tk_rqstp;
struct rpc_cred *cred = req->rq_cred;
struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
gc_base);
struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
__be32 *cred_len;
u32 maj_stat = 0;
struct xdr_netobj mic;
struct kvec iov;
struct xdr_buf verf_buf;
dprintk("RPC: %5u %s\n", task->tk_pid, __func__);
*p++ = htonl(RPC_AUTH_GSS);
cred_len = p++;
spin_lock(&ctx->gc_seq_lock);
req->rq_seqno = ctx->gc_seq++;
spin_unlock(&ctx->gc_seq_lock);
*p++ = htonl((u32) RPC_GSS_VERSION);
*p++ = htonl((u32) ctx->gc_proc);
*p++ = htonl((u32) req->rq_seqno);
*p++ = htonl((u32) gss_cred->gc_service);
p = xdr_encode_netobj(p, &ctx->gc_wire_ctx);
*cred_len = htonl((p - (cred_len + 1)) << 2);
/* We compute the checksum for the verifier over the xdr-encoded bytes
* starting with the xid and ending at the end of the credential: */
iov.iov_base = xprt_skip_transport_header(req->rq_xprt,
req->rq_snd_buf.head[0].iov_base);
iov.iov_len = (u8 *)p - (u8 *)iov.iov_base;
xdr_buf_from_iov(&iov, &verf_buf);
/* set verifier flavor*/
*p++ = htonl(RPC_AUTH_GSS);
mic.data = (u8 *)(p + 1);
maj_stat = gss_get_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
if (maj_stat == GSS_S_CONTEXT_EXPIRED) {
clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
} else if (maj_stat != 0) {
printk("gss_marshal: gss_get_mic FAILED (%d)\n", maj_stat);
goto out_put_ctx;
}
p = xdr_encode_opaque(p, NULL, mic.len);
gss_put_ctx(ctx);
return p;
out_put_ctx:
gss_put_ctx(ctx);
return NULL;
}
static int gss_renew_cred(struct rpc_task *task)
{
struct rpc_cred *oldcred = task->tk_rqstp->rq_cred;
struct gss_cred *gss_cred = container_of(oldcred,
struct gss_cred,
gc_base);
struct rpc_auth *auth = oldcred->cr_auth;
struct auth_cred acred = {
.uid = oldcred->cr_uid,
.principal = gss_cred->gc_principal,
.machine_cred = (gss_cred->gc_principal != NULL ? 1 : 0),
};
struct rpc_cred *new;
new = gss_lookup_cred(auth, &acred, RPCAUTH_LOOKUP_NEW);
if (IS_ERR(new))
return PTR_ERR(new);
task->tk_rqstp->rq_cred = new;
put_rpccred(oldcred);
return 0;
}
static int gss_cred_is_negative_entry(struct rpc_cred *cred)
{
if (test_bit(RPCAUTH_CRED_NEGATIVE, &cred->cr_flags)) {
unsigned long now = jiffies;
unsigned long begin, expire;
struct gss_cred *gss_cred;
gss_cred = container_of(cred, struct gss_cred, gc_base);
begin = gss_cred->gc_upcall_timestamp;
expire = begin + gss_expired_cred_retry_delay * HZ;
if (time_in_range_open(now, begin, expire))
return 1;
}
return 0;
}
/*
* Refresh credentials. XXX - finish
*/
static int
gss_refresh(struct rpc_task *task)
{
struct rpc_cred *cred = task->tk_rqstp->rq_cred;
int ret = 0;
if (gss_cred_is_negative_entry(cred))
return -EKEYEXPIRED;
if (!test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags) &&
!test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags)) {
ret = gss_renew_cred(task);
if (ret < 0)
goto out;
cred = task->tk_rqstp->rq_cred;
}
if (test_bit(RPCAUTH_CRED_NEW, &cred->cr_flags))
ret = gss_refresh_upcall(task);
out:
return ret;
}
/* Dummy refresh routine: used only when destroying the context */
static int
gss_refresh_null(struct rpc_task *task)
{
return 0;
}
static __be32 *
gss_validate(struct rpc_task *task, __be32 *p)
{
struct rpc_cred *cred = task->tk_rqstp->rq_cred;
struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
__be32 seq;
struct kvec iov;
struct xdr_buf verf_buf;
struct xdr_netobj mic;
u32 flav,len;
u32 maj_stat;
__be32 *ret = ERR_PTR(-EIO);
dprintk("RPC: %5u %s\n", task->tk_pid, __func__);
flav = ntohl(*p++);
if ((len = ntohl(*p++)) > RPC_MAX_AUTH_SIZE)
goto out_bad;
if (flav != RPC_AUTH_GSS)
goto out_bad;
seq = htonl(task->tk_rqstp->rq_seqno);
iov.iov_base = &seq;
iov.iov_len = sizeof(seq);
xdr_buf_from_iov(&iov, &verf_buf);
mic.data = (u8 *)p;
mic.len = len;
ret = ERR_PTR(-EACCES);
maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &verf_buf, &mic);
if (maj_stat == GSS_S_CONTEXT_EXPIRED)
clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
if (maj_stat) {
dprintk("RPC: %5u %s: gss_verify_mic returned error 0x%08x\n",
task->tk_pid, __func__, maj_stat);
goto out_bad;
}
/* We leave it to unwrap to calculate au_rslack. For now we just
* calculate the length of the verifier: */
cred->cr_auth->au_verfsize = XDR_QUADLEN(len) + 2;
gss_put_ctx(ctx);
dprintk("RPC: %5u %s: gss_verify_mic succeeded.\n",
task->tk_pid, __func__);
return p + XDR_QUADLEN(len);
out_bad:
gss_put_ctx(ctx);
dprintk("RPC: %5u %s failed ret %ld.\n", task->tk_pid, __func__,
PTR_ERR(ret));
return ret;
}
static void gss_wrap_req_encode(kxdreproc_t encode, struct rpc_rqst *rqstp,
__be32 *p, void *obj)
{
struct xdr_stream xdr;
xdr_init_encode(&xdr, &rqstp->rq_snd_buf, p);
encode(rqstp, &xdr, obj);
}
static inline int
gss_wrap_req_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
kxdreproc_t encode, struct rpc_rqst *rqstp,
__be32 *p, void *obj)
{
struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
struct xdr_buf integ_buf;
__be32 *integ_len = NULL;
struct xdr_netobj mic;
u32 offset;
__be32 *q;
struct kvec *iov;
u32 maj_stat = 0;
int status = -EIO;
integ_len = p++;
offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
*p++ = htonl(rqstp->rq_seqno);
gss_wrap_req_encode(encode, rqstp, p, obj);
if (xdr_buf_subsegment(snd_buf, &integ_buf,
offset, snd_buf->len - offset))
return status;
*integ_len = htonl(integ_buf.len);
/* guess whether we're in the head or the tail: */
if (snd_buf->page_len || snd_buf->tail[0].iov_len)
iov = snd_buf->tail;
else
iov = snd_buf->head;
p = iov->iov_base + iov->iov_len;
mic.data = (u8 *)(p + 1);
maj_stat = gss_get_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
status = -EIO; /* XXX? */
if (maj_stat == GSS_S_CONTEXT_EXPIRED)
clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
else if (maj_stat)
return status;
q = xdr_encode_opaque(p, NULL, mic.len);
offset = (u8 *)q - (u8 *)p;
iov->iov_len += offset;
snd_buf->len += offset;
return 0;
}
static void
priv_release_snd_buf(struct rpc_rqst *rqstp)
{
int i;
for (i=0; i < rqstp->rq_enc_pages_num; i++)
__free_page(rqstp->rq_enc_pages[i]);
kfree(rqstp->rq_enc_pages);
}
static int
alloc_enc_pages(struct rpc_rqst *rqstp)
{
struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
int first, last, i;
if (snd_buf->page_len == 0) {
rqstp->rq_enc_pages_num = 0;
return 0;
}
first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_CACHE_SHIFT;
rqstp->rq_enc_pages_num = last - first + 1 + 1;
rqstp->rq_enc_pages
= kmalloc(rqstp->rq_enc_pages_num * sizeof(struct page *),
GFP_NOFS);
if (!rqstp->rq_enc_pages)
goto out;
for (i=0; i < rqstp->rq_enc_pages_num; i++) {
rqstp->rq_enc_pages[i] = alloc_page(GFP_NOFS);
if (rqstp->rq_enc_pages[i] == NULL)
goto out_free;
}
rqstp->rq_release_snd_buf = priv_release_snd_buf;
return 0;
out_free:
rqstp->rq_enc_pages_num = i;
priv_release_snd_buf(rqstp);
out:
return -EAGAIN;
}
static inline int
gss_wrap_req_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
kxdreproc_t encode, struct rpc_rqst *rqstp,
__be32 *p, void *obj)
{
struct xdr_buf *snd_buf = &rqstp->rq_snd_buf;
u32 offset;
u32 maj_stat;
int status;
__be32 *opaque_len;
struct page **inpages;
int first;
int pad;
struct kvec *iov;
char *tmp;
opaque_len = p++;
offset = (u8 *)p - (u8 *)snd_buf->head[0].iov_base;
*p++ = htonl(rqstp->rq_seqno);
gss_wrap_req_encode(encode, rqstp, p, obj);
status = alloc_enc_pages(rqstp);
if (status)
return status;
first = snd_buf->page_base >> PAGE_CACHE_SHIFT;
inpages = snd_buf->pages + first;
snd_buf->pages = rqstp->rq_enc_pages;
snd_buf->page_base -= first << PAGE_CACHE_SHIFT;
/*
* Give the tail its own page, in case we need extra space in the
* head when wrapping:
*
* call_allocate() allocates twice the slack space required
* by the authentication flavor to rq_callsize.
* For GSS, slack is GSS_CRED_SLACK.
*/
if (snd_buf->page_len || snd_buf->tail[0].iov_len) {
tmp = page_address(rqstp->rq_enc_pages[rqstp->rq_enc_pages_num - 1]);
memcpy(tmp, snd_buf->tail[0].iov_base, snd_buf->tail[0].iov_len);
snd_buf->tail[0].iov_base = tmp;
}
maj_stat = gss_wrap(ctx->gc_gss_ctx, offset, snd_buf, inpages);
/* slack space should prevent this ever happening: */
BUG_ON(snd_buf->len > snd_buf->buflen);
status = -EIO;
/* We're assuming that when GSS_S_CONTEXT_EXPIRED, the encryption was
* done anyway, so it's safe to put the request on the wire: */
if (maj_stat == GSS_S_CONTEXT_EXPIRED)
clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
else if (maj_stat)
return status;
*opaque_len = htonl(snd_buf->len - offset);
/* guess whether we're in the head or the tail: */
if (snd_buf->page_len || snd_buf->tail[0].iov_len)
iov = snd_buf->tail;
else
iov = snd_buf->head;
p = iov->iov_base + iov->iov_len;
pad = 3 - ((snd_buf->len - offset - 1) & 3);
memset(p, 0, pad);
iov->iov_len += pad;
snd_buf->len += pad;
return 0;
}
static int
gss_wrap_req(struct rpc_task *task,
kxdreproc_t encode, void *rqstp, __be32 *p, void *obj)
{
struct rpc_cred *cred = task->tk_rqstp->rq_cred;
struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
gc_base);
struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
int status = -EIO;
dprintk("RPC: %5u %s\n", task->tk_pid, __func__);
if (ctx->gc_proc != RPC_GSS_PROC_DATA) {
/* The spec seems a little ambiguous here, but I think that not
* wrapping context destruction requests makes the most sense.
*/
gss_wrap_req_encode(encode, rqstp, p, obj);
status = 0;
goto out;
}
switch (gss_cred->gc_service) {
case RPC_GSS_SVC_NONE:
gss_wrap_req_encode(encode, rqstp, p, obj);
status = 0;
break;
case RPC_GSS_SVC_INTEGRITY:
status = gss_wrap_req_integ(cred, ctx, encode, rqstp, p, obj);
break;
case RPC_GSS_SVC_PRIVACY:
status = gss_wrap_req_priv(cred, ctx, encode, rqstp, p, obj);
break;
}
out:
gss_put_ctx(ctx);
dprintk("RPC: %5u %s returning %d\n", task->tk_pid, __func__, status);
return status;
}
static inline int
gss_unwrap_resp_integ(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
struct rpc_rqst *rqstp, __be32 **p)
{
struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf;
struct xdr_buf integ_buf;
struct xdr_netobj mic;
u32 data_offset, mic_offset;
u32 integ_len;
u32 maj_stat;
int status = -EIO;
integ_len = ntohl(*(*p)++);
if (integ_len & 3)
return status;
data_offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
mic_offset = integ_len + data_offset;
if (mic_offset > rcv_buf->len)
return status;
if (ntohl(*(*p)++) != rqstp->rq_seqno)
return status;
if (xdr_buf_subsegment(rcv_buf, &integ_buf, data_offset,
mic_offset - data_offset))
return status;
if (xdr_buf_read_netobj(rcv_buf, &mic, mic_offset))
return status;
maj_stat = gss_verify_mic(ctx->gc_gss_ctx, &integ_buf, &mic);
if (maj_stat == GSS_S_CONTEXT_EXPIRED)
clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
if (maj_stat != GSS_S_COMPLETE)
return status;
return 0;
}
static inline int
gss_unwrap_resp_priv(struct rpc_cred *cred, struct gss_cl_ctx *ctx,
struct rpc_rqst *rqstp, __be32 **p)
{
struct xdr_buf *rcv_buf = &rqstp->rq_rcv_buf;
u32 offset;
u32 opaque_len;
u32 maj_stat;
int status = -EIO;
opaque_len = ntohl(*(*p)++);
offset = (u8 *)(*p) - (u8 *)rcv_buf->head[0].iov_base;
if (offset + opaque_len > rcv_buf->len)
return status;
/* remove padding: */
rcv_buf->len = offset + opaque_len;
maj_stat = gss_unwrap(ctx->gc_gss_ctx, offset, rcv_buf);
if (maj_stat == GSS_S_CONTEXT_EXPIRED)
clear_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags);
if (maj_stat != GSS_S_COMPLETE)
return status;
if (ntohl(*(*p)++) != rqstp->rq_seqno)
return status;
return 0;
}
static int
gss_unwrap_req_decode(kxdrdproc_t decode, struct rpc_rqst *rqstp,
__be32 *p, void *obj)
{
struct xdr_stream xdr;
xdr_init_decode(&xdr, &rqstp->rq_rcv_buf, p);
return decode(rqstp, &xdr, obj);
}
static int
gss_unwrap_resp(struct rpc_task *task,
kxdrdproc_t decode, void *rqstp, __be32 *p, void *obj)
{
struct rpc_cred *cred = task->tk_rqstp->rq_cred;
struct gss_cred *gss_cred = container_of(cred, struct gss_cred,
gc_base);
struct gss_cl_ctx *ctx = gss_cred_get_ctx(cred);
__be32 *savedp = p;
struct kvec *head = ((struct rpc_rqst *)rqstp)->rq_rcv_buf.head;
int savedlen = head->iov_len;
int status = -EIO;
if (ctx->gc_proc != RPC_GSS_PROC_DATA)
goto out_decode;
switch (gss_cred->gc_service) {
case RPC_GSS_SVC_NONE:
break;
case RPC_GSS_SVC_INTEGRITY:
status = gss_unwrap_resp_integ(cred, ctx, rqstp, &p);
if (status)
goto out;
break;
case RPC_GSS_SVC_PRIVACY:
status = gss_unwrap_resp_priv(cred, ctx, rqstp, &p);
if (status)
goto out;
break;
}
/* take into account extra slack for integrity and privacy cases: */
cred->cr_auth->au_rslack = cred->cr_auth->au_verfsize + (p - savedp)
+ (savedlen - head->iov_len);
out_decode:
status = gss_unwrap_req_decode(decode, rqstp, p, obj);
out:
gss_put_ctx(ctx);
dprintk("RPC: %5u %s returning %d\n",
task->tk_pid, __func__, status);
return status;
}
static const struct rpc_authops authgss_ops = {
.owner = THIS_MODULE,
.au_flavor = RPC_AUTH_GSS,
.au_name = "RPCSEC_GSS",
.create = gss_create,
.destroy = gss_destroy,
.lookup_cred = gss_lookup_cred,
.crcreate = gss_create_cred,
.list_pseudoflavors = gss_mech_list_pseudoflavors,
.info2flavor = gss_mech_info2flavor,
.flavor2info = gss_mech_flavor2info,
};
static const struct rpc_credops gss_credops = {
.cr_name = "AUTH_GSS",
.crdestroy = gss_destroy_cred,
.cr_init = gss_cred_init,
.crbind = rpcauth_generic_bind_cred,
.crmatch = gss_match,
.crmarshal = gss_marshal,
.crrefresh = gss_refresh,
.crvalidate = gss_validate,
.crwrap_req = gss_wrap_req,
.crunwrap_resp = gss_unwrap_resp,
.crkey_timeout = gss_key_timeout,
.crstringify_acceptor = gss_stringify_acceptor,
};
static const struct rpc_credops gss_nullops = {
.cr_name = "AUTH_GSS",
.crdestroy = gss_destroy_nullcred,
.crbind = rpcauth_generic_bind_cred,
.crmatch = gss_match,
.crmarshal = gss_marshal,
.crrefresh = gss_refresh_null,
.crvalidate = gss_validate,
.crwrap_req = gss_wrap_req,
.crunwrap_resp = gss_unwrap_resp,
.crstringify_acceptor = gss_stringify_acceptor,
};
static const struct rpc_pipe_ops gss_upcall_ops_v0 = {
.upcall = rpc_pipe_generic_upcall,
.downcall = gss_pipe_downcall,
.destroy_msg = gss_pipe_destroy_msg,
.open_pipe = gss_pipe_open_v0,
.release_pipe = gss_pipe_release,
};
static const struct rpc_pipe_ops gss_upcall_ops_v1 = {
.upcall = rpc_pipe_generic_upcall,
.downcall = gss_pipe_downcall,
.destroy_msg = gss_pipe_destroy_msg,
.open_pipe = gss_pipe_open_v1,
.release_pipe = gss_pipe_release,
};
static __net_init int rpcsec_gss_init_net(struct net *net)
{
return gss_svc_init_net(net);
}
static __net_exit void rpcsec_gss_exit_net(struct net *net)
{
gss_svc_shutdown_net(net);
}
static struct pernet_operations rpcsec_gss_net_ops = {
.init = rpcsec_gss_init_net,
.exit = rpcsec_gss_exit_net,
};
/*
* Initialize RPCSEC_GSS module
*/
static int __init init_rpcsec_gss(void)
{
int err = 0;
err = rpcauth_register(&authgss_ops);
if (err)
goto out;
err = gss_svc_init();
if (err)
goto out_unregister;
err = register_pernet_subsys(&rpcsec_gss_net_ops);
if (err)
goto out_svc_exit;
rpc_init_wait_queue(&pipe_version_rpc_waitqueue, "gss pipe version");
return 0;
out_svc_exit:
gss_svc_shutdown();
out_unregister:
rpcauth_unregister(&authgss_ops);
out:
return err;
}
static void __exit exit_rpcsec_gss(void)
{
unregister_pernet_subsys(&rpcsec_gss_net_ops);
gss_svc_shutdown();
rpcauth_unregister(&authgss_ops);
rcu_barrier(); /* Wait for completion of call_rcu()'s */
}
MODULE_ALIAS("rpc-auth-6");
MODULE_LICENSE("GPL");
module_param_named(expired_cred_retry_delay,
gss_expired_cred_retry_delay,
uint, 0644);
MODULE_PARM_DESC(expired_cred_retry_delay, "Timeout (in seconds) until "
"the RPC engine retries an expired credential");
module_param_named(key_expire_timeo,
gss_key_expire_timeo,
uint, 0644);
MODULE_PARM_DESC(key_expire_timeo, "Time (in seconds) at the end of a "
"credential keys lifetime where the NFS layer cleans up "
"prior to key expiration");
module_init(init_rpcsec_gss)
module_exit(exit_rpcsec_gss)