diff options
Diffstat (limited to 'net/sunrpc/auth_gss/auth_gss.c')
| -rw-r--r-- | net/sunrpc/auth_gss/auth_gss.c | 2127 |
1 files changed, 2127 insertions, 0 deletions
diff --git a/net/sunrpc/auth_gss/auth_gss.c b/net/sunrpc/auth_gss/auth_gss.c new file mode 100644 index 000000000..e61c48c1b --- /dev/null +++ b/net/sunrpc/auth_gss/auth_gss.c @@ -0,0 +1,2127 @@ +/* + * 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 <linux/uaccess.h> +#include <linux/hashtable.h> + +#include "auth_gss_internal.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) +{ + refcount_inc(&ctx->count); + return ctx; +} + +static inline void +gss_put_ctx(struct gss_cl_ctx *ctx) +{ + if (refcount_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 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); + refcount_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; +} + +/* XXX: Need some documentation about why UPCALL_BUF_LEN is so small. + * Is user space expecting no more than UPCALL_BUF_LEN bytes? + * Note that there are now _two_ NI_MAXHOST sized data items + * being passed in this string. + */ +#define UPCALL_BUF_LEN 256 + +struct gss_upcall_msg { + refcount_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 (!refcount_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, const struct gss_auth *auth) +{ + struct gss_upcall_msg *pos; + list_for_each_entry(pos, &pipe->in_downcall, list) { + if (!uid_eq(pos->uid, uid)) + continue; + if (auth && pos->auth->service != auth->service) + continue; + refcount_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, gss_msg->auth); + if (old == NULL) { + refcount_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); + refcount_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; + + /* + * target= is a full service principal that names the remote + * identity that we are authenticating to. + */ + if (target_name) { + len = scnprintf(p, buflen, "target=%s ", target_name); + buflen -= len; + p += len; + gss_msg->msg.len += len; + } + + /* + * gssd uses service= and srchost= to select a matching key from + * the system's keytab to use as the source principal. + * + * service= is the service name part of the source principal, + * or "*" (meaning choose any). + * + * srchost= is the hostname part of the source principal. When + * not provided, gssd uses the local hostname. + */ + if (service_name) { + char *c = strchr(service_name, '@'); + + if (!c) + len = scnprintf(p, buflen, "service=%s ", + service_name); + else + len = scnprintf(p, buflen, + "service=%.*s srchost=%s ", + (int)(c - service_name), + service_name, c + 1); + 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); + refcount_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; + refcount_inc(&gss_msg->count); + res = rpc_queue_upcall(gss_new->pipe, &gss_new->msg); + if (res) { + gss_unhash_msg(gss_new); + refcount_dec(&gss_msg->count); + gss_release_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 */ + refcount_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, NULL); + 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); + gss_msg->msg.errno = -EIO; + } + 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; + refcount_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); + refcount_inc(&gss_msg->count); + gss_unhash_msg(gss_msg); + if (msg->errno == -ETIMEDOUT) + warn_gssd(); + gss_release_msg(gss_msg); + } + 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(const 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_flags = 0; + auth->au_ops = &authgss_ops; + auth->au_flavor = flavor; + if (gss_pseudoflavor_to_datatouch(gss_auth->mech, flavor)) + auth->au_flags |= RPCAUTH_AUTH_DATATOUCH; + 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(const 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(const 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(const struct rpc_auth_create_args *args, struct rpc_clnt *clnt) +{ + struct gss_auth *gss_auth; + struct rpc_xprt_switch *xps = rcu_access_pointer(clnt->cl_xpi.xpi_xpswitch); + + 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_xpi.xpi_xpswitch) != xps) + 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); +} + +static int +gss_hash_cred(struct auth_cred *acred, unsigned int hashbits) +{ + return hash_64(from_kuid(&init_user_ns, acred->uid), hashbits); +} + +/* + * 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, GFP_NOFS); +} + +static struct rpc_cred * +gss_create_cred(struct rpc_auth *auth, struct auth_cred *acred, int flags, gfp_t gfp) +{ + 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))) + 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 = NULL; + 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 = kmalloc(4, GFP_NOFS); + if (!seq) + goto out_bad; + *seq = htonl(task->tk_rqstp->rq_seqno); + iov.iov_base = seq; + iov.iov_len = 4; + 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__); + kfree(seq); + 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)); + kfree(seq); + 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); + rqstp->rq_release_snd_buf = NULL; +} + +static int +alloc_enc_pages(struct rpc_rqst *rqstp) +{ + struct xdr_buf *snd_buf = &rqstp->rq_snd_buf; + int first, last, i; + + if (rqstp->rq_release_snd_buf) + rqstp->rq_release_snd_buf(rqstp); + + if (snd_buf->page_len == 0) { + rqstp->rq_enc_pages_num = 0; + return 0; + } + + first = snd_buf->page_base >> PAGE_SHIFT; + last = (snd_buf->page_base + snd_buf->page_len - 1) >> PAGE_SHIFT; + rqstp->rq_enc_pages_num = last - first + 1 + 1; + rqstp->rq_enc_pages + = kmalloc_array(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_SHIFT; + inpages = snd_buf->pages + first; + snd_buf->pages = rqstp->rq_enc_pages; + snd_buf->page_base -= first << PAGE_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, + .hash_cred = gss_hash_cred, + .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) |