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auth_gss.c
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/*
* 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>
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;
#ifdef RPC_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
struct gss_auth {
struct kref kref;
struct rpc_auth rpc_auth;
struct gss_api_mech *mech;
enum rpc_gss_svc service;
struct rpc_clnt *client;
/*
* 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 dentry *dentry[2];
};
/* pipe_version >= 0 if and only if someone has a pipe open. */
static int pipe_version = -1;
static atomic_t pipe_users = ATOMIC_INIT(0);
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_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 inode->i_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_clear_bit();
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();
if (gss_cred->gc_ctx)
ctx = gss_get_ctx(gss_cred->gc_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;
u32 window_size;
int ret;
/* First unsigned int gives the lifetime (in seconds) of the cred */
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 = jiffies + (unsigned long)timeout * HZ * 3 / 4;
/* 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, GFP_NOFS);
if (ret < 0) {
p = ERR_PTR(ret);
goto err;
}
return q;
err:
dprintk("RPC: gss_fill_context returning %ld\n", -PTR_ERR(p));
return p;
}
#define UPCALL_BUF_LEN 128
struct gss_upcall_msg {
atomic_t count;
uid_t uid;
struct rpc_pipe_msg msg;
struct list_head list;
struct gss_auth *auth;
struct rpc_inode *inode;
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(void)
{
int ret;
spin_lock(&pipe_version_lock);
if (pipe_version >= 0) {
atomic_inc(&pipe_users);
ret = pipe_version;
} else
ret = -EAGAIN;
spin_unlock(&pipe_version_lock);
return ret;
}
static void put_pipe_version(void)
{
if (atomic_dec_and_lock(&pipe_users, &pipe_version_lock)) {
pipe_version = -1;
spin_unlock(&pipe_version_lock);
}
}
static void
gss_release_msg(struct gss_upcall_msg *gss_msg)
{
if (!atomic_dec_and_test(&gss_msg->count))
return;
put_pipe_version();
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);
kfree(gss_msg);
}
static struct gss_upcall_msg *
__gss_find_upcall(struct rpc_inode *rpci, uid_t uid)
{
struct gss_upcall_msg *pos;
list_for_each_entry(pos, &rpci->in_downcall, list) {
if (pos->uid != uid)
continue;
atomic_inc(&pos->count);
dprintk("RPC: gss_find_upcall found msg %p\n", pos);
return pos;
}
dprintk("RPC: gss_find_upcall found nothing\n");
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_inode *rpci = gss_msg->inode;
struct inode *inode = &rpci->vfs_inode;
struct gss_upcall_msg *old;
spin_lock(&inode->i_lock);
old = __gss_find_upcall(rpci, gss_msg->uid);
if (old == NULL) {
atomic_inc(&gss_msg->count);
list_add(&gss_msg->list, &rpci->in_downcall);
} else
gss_msg = old;
spin_unlock(&inode->i_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 inode *inode = &gss_msg->inode->vfs_inode;
if (list_empty(&gss_msg->list))
return;
spin_lock(&inode->i_lock);
if (!list_empty(&gss_msg->list))
__gss_unhash_msg(gss_msg);
spin_unlock(&inode->i_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 inode *inode = &gss_msg->inode->vfs_inode;
spin_lock(&inode->i_lock);
gss_handle_downcall_result(gss_cred, gss_msg);
spin_unlock(&inode->i_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)
{
gss_msg->msg.data = &gss_msg->uid;
gss_msg->msg.len = sizeof(gss_msg->uid);
}
static void gss_encode_v1_msg(struct gss_upcall_msg *gss_msg,
struct rpc_clnt *clnt, int machine_cred)
{
struct gss_api_mech *mech = gss_msg->auth->mech;
char *p = gss_msg->databuf;
int len = 0;
gss_msg->msg.len = sprintf(gss_msg->databuf, "mech=%s uid=%d ",
mech->gm_name,
gss_msg->uid);
p += gss_msg->msg.len;
if (clnt->cl_principal) {
len = sprintf(p, "target=%s ", clnt->cl_principal);
p += len;
gss_msg->msg.len += len;
}
if (machine_cred) {
len = sprintf(p, "service=* ");
p += len;
gss_msg->msg.len += len;
} else if (!strcmp(clnt->cl_program->name, "nfs4_cb")) {
len = sprintf(p, "service=nfs ");
p += len;
gss_msg->msg.len += len;
}
if (mech->gm_upcall_enctypes) {
len = sprintf(p, mech->gm_upcall_enctypes);
p += len;
gss_msg->msg.len += len;
}
len = sprintf(p, "\n");
gss_msg->msg.len += len;
gss_msg->msg.data = gss_msg->databuf;
BUG_ON(gss_msg->msg.len > UPCALL_BUF_LEN);
}
static void gss_encode_msg(struct gss_upcall_msg *gss_msg,
struct rpc_clnt *clnt, int machine_cred)
{
if (pipe_version == 0)
gss_encode_v0_msg(gss_msg);
else /* pipe_version == 1 */
gss_encode_v1_msg(gss_msg, clnt, machine_cred);
}
static inline struct gss_upcall_msg *
gss_alloc_msg(struct gss_auth *gss_auth, uid_t uid, struct rpc_clnt *clnt,
int machine_cred)
{
struct gss_upcall_msg *gss_msg;
int vers;
gss_msg = kzalloc(sizeof(*gss_msg), GFP_NOFS);
if (gss_msg == NULL)
return ERR_PTR(-ENOMEM);
vers = get_pipe_version();
if (vers < 0) {
kfree(gss_msg);
return ERR_PTR(vers);
}
gss_msg->inode = RPC_I(gss_auth->dentry[vers]->d_inode);
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;
gss_encode_msg(gss_msg, clnt, machine_cred);
return gss_msg;
}
static struct gss_upcall_msg *
gss_setup_upcall(struct rpc_clnt *clnt, 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;
uid_t uid = cred->cr_uid;
gss_new = gss_alloc_msg(gss_auth, uid, clnt, gss_cred->gc_machine_cred);
if (IS_ERR(gss_new))
return gss_new;
gss_msg = gss_add_msg(gss_new);
if (gss_msg == gss_new) {
struct inode *inode = &gss_new->inode->vfs_inode;
int res = rpc_queue_upcall(inode, &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)
{
static unsigned long ratelimit;
unsigned long now = jiffies;
if (time_after(now, ratelimit)) {
printk(KERN_WARNING "RPC: AUTH_GSS upcall timed out.\n"
"Please check user daemon is running.\n");
ratelimit = now + 15*HZ;
}
}
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 inode *inode;
int err = 0;
dprintk("RPC: %5u gss_refresh_upcall for uid %u\n", task->tk_pid,
cred->cr_uid);
gss_msg = gss_setup_upcall(task->tk_client, 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 0;
}
if (IS_ERR(gss_msg)) {
err = PTR_ERR(gss_msg);
goto out;
}
inode = &gss_msg->inode->vfs_inode;
spin_lock(&inode->i_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(&inode->i_lock);
gss_release_msg(gss_msg);
out:
dprintk("RPC: %5u gss_refresh_upcall for uid %u result %d\n",
task->tk_pid, cred->cr_uid, err);
return err;
}
static inline int
gss_create_upcall(struct gss_auth *gss_auth, struct gss_cred *gss_cred)
{
struct inode *inode;
struct rpc_cred *cred = &gss_cred->gc_base;
struct gss_upcall_msg *gss_msg;
DEFINE_WAIT(wait);
int err = 0;
dprintk("RPC: gss_upcall for uid %u\n", cred->cr_uid);
retry:
gss_msg = gss_setup_upcall(gss_auth->client, gss_auth, cred);
if (PTR_ERR(gss_msg) == -EAGAIN) {
err = wait_event_interruptible_timeout(pipe_version_waitqueue,
pipe_version >= 0, 15*HZ);
if (err)
goto out;
if (pipe_version < 0)
warn_gssd();
goto retry;
}
if (IS_ERR(gss_msg)) {
err = PTR_ERR(gss_msg);
goto out;
}
inode = &gss_msg->inode->vfs_inode;
for (;;) {
prepare_to_wait(&gss_msg->waitqueue, &wait, TASK_INTERRUPTIBLE);
spin_lock(&inode->i_lock);
if (gss_msg->ctx != NULL || gss_msg->msg.errno < 0) {
break;
}
spin_unlock(&inode->i_lock);
if (signalled()) {
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(&inode->i_lock);
out_intr:
finish_wait(&gss_msg->waitqueue, &wait);
gss_release_msg(gss_msg);
out:
dprintk("RPC: gss_create_upcall for uid %u result %d\n",
cred->cr_uid, err);
return err;
}
static ssize_t
gss_pipe_upcall(struct file *filp, struct rpc_pipe_msg *msg,
char __user *dst, size_t buflen)
{
char *data = (char *)msg->data + msg->copied;
size_t mlen = min(msg->len, buflen);
unsigned long left;
left = copy_to_user(dst, data, mlen);
if (left == mlen) {
msg->errno = -EFAULT;
return -EFAULT;
}
mlen -= left;
msg->copied += mlen;
msg->errno = 0;
return mlen;
}
#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 inode *inode = filp->f_path.dentry->d_inode;
struct gss_cl_ctx *ctx;
uid_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, &uid, sizeof(uid));
if (IS_ERR(p)) {
err = PTR_ERR(p);
goto err;
}
err = -ENOMEM;
ctx = gss_alloc_context();
if (ctx == NULL)
goto err;
err = -ENOENT;
/* Find a matching upcall */
spin_lock(&inode->i_lock);
gss_msg = __gss_find_upcall(RPC_I(inode), uid);
if (gss_msg == NULL) {
spin_unlock(&inode->i_lock);
goto err_put_ctx;
}
list_del_init(&gss_msg->list);
spin_unlock(&inode->i_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(&inode->i_lock);
__gss_unhash_msg(gss_msg);
spin_unlock(&inode->i_lock);
gss_release_msg(gss_msg);
err_put_ctx:
gss_put_ctx(ctx);
err:
kfree(buf);
out:
dprintk("RPC: gss_pipe_downcall returning %Zd\n", err);
return err;
}
static int gss_pipe_open(struct inode *inode, int new_version)
{
int ret = 0;
spin_lock(&pipe_version_lock);
if (pipe_version < 0) {
/* First open of any gss pipe determines the version: */
pipe_version = new_version;
rpc_wake_up(&pipe_version_rpc_waitqueue);
wake_up(&pipe_version_waitqueue);
} else if (pipe_version != new_version) {
/* Trying to open a pipe of a different version */
ret = -EBUSY;
goto out;
}
atomic_inc(&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 rpc_inode *rpci = RPC_I(inode);
struct gss_upcall_msg *gss_msg;
spin_lock(&inode->i_lock);
while (!list_empty(&rpci->in_downcall)) {
gss_msg = list_entry(rpci->in_downcall.next,
struct gss_upcall_msg, list);
gss_msg->msg.errno = -EPIPE;
atomic_inc(&gss_msg->count);
__gss_unhash_msg(gss_msg);
spin_unlock(&inode->i_lock);
gss_release_msg(gss_msg);
spin_lock(&inode->i_lock);
}
spin_unlock(&inode->i_lock);
put_pipe_version();
}
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: gss_pipe_destroy_msg releasing msg %p\n",
gss_msg);
atomic_inc(&gss_msg->count);
gss_unhash_msg(gss_msg);
if (msg->errno == -ETIMEDOUT)
warn_gssd();
gss_release_msg(gss_msg);
}
}
/*
* NOTE: we have the opportunity to use different
* parameters based on the input flavor (which must be a pseudoflavor)
*/
static struct rpc_auth *
gss_create(struct rpc_clnt *clnt, rpc_authflavor_t flavor)
{
struct gss_auth *gss_auth;
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;
gss_auth->client = clnt;
err = -EINVAL;
gss_auth->mech = gss_mech_get_by_pseudoflavor(flavor);
if (!gss_auth->mech) {
printk(KERN_WARNING "%s: Pseudoflavor %d not found!\n",
__func__, flavor);
goto err_free;
}
gss_auth->service = gss_pseudoflavor_to_service(gss_auth->mech, flavor);
if (gss_auth->service == 0)
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);
/*
* 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_auth->dentry[1] = rpc_mkpipe(clnt->cl_path.dentry,
"gssd",
clnt, &gss_upcall_ops_v1,
RPC_PIPE_WAIT_FOR_OPEN);
if (IS_ERR(gss_auth->dentry[1])) {
err = PTR_ERR(gss_auth->dentry[1]);
goto err_put_mech;
}
gss_auth->dentry[0] = rpc_mkpipe(clnt->cl_path.dentry,
gss_auth->mech->gm_name,
clnt, &gss_upcall_ops_v0,
RPC_PIPE_WAIT_FOR_OPEN);
if (IS_ERR(gss_auth->dentry[0])) {
err = PTR_ERR(gss_auth->dentry[0]);
goto err_unlink_pipe_1;
}
err = rpcauth_init_credcache(auth);
if (err)
goto err_unlink_pipe_0;
return auth;
err_unlink_pipe_0:
rpc_unlink(gss_auth->dentry[0]);
err_unlink_pipe_1:
rpc_unlink(gss_auth->dentry[1]);
err_put_mech:
gss_mech_put(gss_auth->mech);
err_free:
kfree(gss_auth);
out_dec:
module_put(THIS_MODULE);
return ERR_PTR(err);
}
static void
gss_free(struct gss_auth *gss_auth)
{
rpc_unlink(gss_auth->dentry[1]);
rpc_unlink(gss_auth->dentry[0]);
gss_mech_put(gss_auth->mech);
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_destroy(struct rpc_auth *auth)
{
struct gss_auth *gss_auth;
dprintk("RPC: destroying GSS authenticator %p flavor %d\n",
auth, auth->au_flavor);
rpcauth_destroy_credcache(auth);
gss_auth = container_of(auth, struct gss_auth, rpc_auth);
kref_put(&gss_auth->kref, gss_free_callback);
}
/*
* 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 rpc_task *task;
if (gss_cred->gc_ctx == NULL ||
test_bit(RPCAUTH_CRED_UPTODATE, &cred->cr_flags) == 0)
return 0;
gss_cred->gc_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: gss_free_ctx\n");
gss_delete_sec_context(&ctx->gc_gss_ctx);
kfree(ctx->gc_wire_ctx.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: gss_free_cred %p\n", 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 = gss_cred->gc_ctx;
rcu_assign_pointer(gss_cred->gc_ctx, NULL);
call_rcu(&cred->cr_rcu, gss_free_cred_callback);
if (ctx)
gss_put_ctx(ctx);
kref_put(&gss_auth->kref, gss_free_callback);
}
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;