/* * Copyright (c) 2004 The Regents of the University of Michigan. * Copyright (c) 2012 Jeff Layton <jlayton@redhat.com> * All rights reserved. * * Andy Adamson <andros@citi.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/file.h> #include <linux/slab.h> #include <linux/namei.h> #include <linux/crypto.h> #include <linux/sched.h> #include <linux/fs.h> #include <linux/module.h> #include <net/net_namespace.h> #include <linux/sunrpc/rpc_pipe_fs.h> #include <linux/sunrpc/clnt.h> #include <linux/nfsd/cld.h> #include "nfsd.h" #include "state.h" #include "vfs.h" #include "netns.h" #define NFSDDBG_FACILITY NFSDDBG_PROC /* Declarations */ struct nfsd4_client_tracking_ops { int (*init)(struct net *); void (*exit)(struct net *); void (*create)(struct nfs4_client *); void (*remove)(struct nfs4_client *); int (*check)(struct nfs4_client *); void (*grace_done)(struct nfsd_net *); }; /* Globals */ static char user_recovery_dirname[PATH_MAX] = "/var/lib/nfs/v4recovery"; static int nfs4_save_creds(const struct cred **original_creds) { struct cred *new; new = prepare_creds(); if (!new) return -ENOMEM; new->fsuid = GLOBAL_ROOT_UID; new->fsgid = GLOBAL_ROOT_GID; *original_creds = override_creds(new); put_cred(new); return 0; } static void nfs4_reset_creds(const struct cred *original) { revert_creds(original); } static void md5_to_hex(char *out, char *md5) { int i; for (i=0; i<16; i++) { unsigned char c = md5[i]; *out++ = '0' + ((c&0xf0)>>4) + (c>=0xa0)*('a'-'9'-1); *out++ = '0' + (c&0x0f) + ((c&0x0f)>=0x0a)*('a'-'9'-1); } *out = '\0'; } static int nfs4_make_rec_clidname(char *dname, const struct xdr_netobj *clname) { struct xdr_netobj cksum; struct hash_desc desc; struct scatterlist sg; int status; dprintk("NFSD: nfs4_make_rec_clidname for %.*s\n", clname->len, clname->data); desc.flags = CRYPTO_TFM_REQ_MAY_SLEEP; desc.tfm = crypto_alloc_hash("md5", 0, CRYPTO_ALG_ASYNC); if (IS_ERR(desc.tfm)) { status = PTR_ERR(desc.tfm); goto out_no_tfm; } cksum.len = crypto_hash_digestsize(desc.tfm); cksum.data = kmalloc(cksum.len, GFP_KERNEL); if (cksum.data == NULL) { status = -ENOMEM; goto out; } sg_init_one(&sg, clname->data, clname->len); status = crypto_hash_digest(&desc, &sg, sg.length, cksum.data); if (status) goto out; md5_to_hex(dname, cksum.data); status = 0; out: kfree(cksum.data); crypto_free_hash(desc.tfm); out_no_tfm: return status; } /* * If we had an error generating the recdir name for the legacy tracker * then warn the admin. If the error doesn't appear to be transient, * then disable recovery tracking. */ static void legacy_recdir_name_error(struct nfs4_client *clp, int error) { printk(KERN_ERR "NFSD: unable to generate recoverydir " "name (%d).\n", error); /* * if the algorithm just doesn't exist, then disable the recovery * tracker altogether. The crypto libs will generally return this if * FIPS is enabled as well. */ if (error == -ENOENT) { printk(KERN_ERR "NFSD: disabling legacy clientid tracking. " "Reboot recovery will not function correctly!\n"); nfsd4_client_tracking_exit(clp->net); } } static void nfsd4_create_clid_dir(struct nfs4_client *clp) { const struct cred *original_cred; char dname[HEXDIR_LEN]; struct dentry *dir, *dentry; struct nfs4_client_reclaim *crp; int status; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); if (test_and_set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; if (!nn->rec_file) return; status = nfs4_make_rec_clidname(dname, &clp->cl_name); if (status) return legacy_recdir_name_error(clp, status); status = nfs4_save_creds(&original_cred); if (status < 0) return; status = mnt_want_write_file(nn->rec_file); if (status) goto out_creds; dir = nn->rec_file->f_path.dentry; /* lock the parent */ mutex_lock(&dir->d_inode->i_mutex); dentry = lookup_one_len(dname, dir, HEXDIR_LEN-1); if (IS_ERR(dentry)) { status = PTR_ERR(dentry); goto out_unlock; } if (dentry->d_inode) /* * In the 4.1 case, where we're called from * reclaim_complete(), records from the previous reboot * may still be left, so this is OK. * * In the 4.0 case, we should never get here; but we may * as well be forgiving and just succeed silently. */ goto out_put; status = vfs_mkdir(dir->d_inode, dentry, S_IRWXU); out_put: dput(dentry); out_unlock: mutex_unlock(&dir->d_inode->i_mutex); if (status == 0) { if (nn->in_grace) { crp = nfs4_client_to_reclaim(dname, nn); if (crp) crp->cr_clp = clp; } vfs_fsync(nn->rec_file, 0); } else { printk(KERN_ERR "NFSD: failed to write recovery record" " (err %d); please check that %s exists" " and is writeable", status, user_recovery_dirname); } mnt_drop_write_file(nn->rec_file); out_creds: nfs4_reset_creds(original_cred); } typedef int (recdir_func)(struct dentry *, struct dentry *, struct nfsd_net *); struct name_list { char name[HEXDIR_LEN]; struct list_head list; }; struct nfs4_dir_ctx { struct dir_context ctx; struct list_head names; }; static int nfsd4_build_namelist(struct dir_context *__ctx, const char *name, int namlen, loff_t offset, u64 ino, unsigned int d_type) { struct nfs4_dir_ctx *ctx = container_of(__ctx, struct nfs4_dir_ctx, ctx); struct name_list *entry; if (namlen != HEXDIR_LEN - 1) return 0; entry = kmalloc(sizeof(struct name_list), GFP_KERNEL); if (entry == NULL) return -ENOMEM; memcpy(entry->name, name, HEXDIR_LEN - 1); entry->name[HEXDIR_LEN - 1] = '\0'; list_add(&entry->list, &ctx->names); return 0; } static int nfsd4_list_rec_dir(recdir_func *f, struct nfsd_net *nn) { const struct cred *original_cred; struct dentry *dir = nn->rec_file->f_path.dentry; struct nfs4_dir_ctx ctx = { .ctx.actor = nfsd4_build_namelist, .names = LIST_HEAD_INIT(ctx.names) }; int status; status = nfs4_save_creds(&original_cred); if (status < 0) return status; status = vfs_llseek(nn->rec_file, 0, SEEK_SET); if (status < 0) { nfs4_reset_creds(original_cred); return status; } status = iterate_dir(nn->rec_file, &ctx.ctx); mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT); while (!list_empty(&ctx.names)) { struct name_list *entry; entry = list_entry(ctx.names.next, struct name_list, list); if (!status) { struct dentry *dentry; dentry = lookup_one_len(entry->name, dir, HEXDIR_LEN-1); if (IS_ERR(dentry)) { status = PTR_ERR(dentry); break; } status = f(dir, dentry, nn); dput(dentry); } list_del(&entry->list); kfree(entry); } mutex_unlock(&dir->d_inode->i_mutex); nfs4_reset_creds(original_cred); return status; } static int nfsd4_unlink_clid_dir(char *name, int namlen, struct nfsd_net *nn) { struct dentry *dir, *dentry; int status; dprintk("NFSD: nfsd4_unlink_clid_dir. name %.*s\n", namlen, name); dir = nn->rec_file->f_path.dentry; mutex_lock_nested(&dir->d_inode->i_mutex, I_MUTEX_PARENT); dentry = lookup_one_len(name, dir, namlen); if (IS_ERR(dentry)) { status = PTR_ERR(dentry); goto out_unlock; } status = -ENOENT; if (!dentry->d_inode) goto out; status = vfs_rmdir(dir->d_inode, dentry); out: dput(dentry); out_unlock: mutex_unlock(&dir->d_inode->i_mutex); return status; } static void nfsd4_remove_clid_dir(struct nfs4_client *clp) { const struct cred *original_cred; struct nfs4_client_reclaim *crp; char dname[HEXDIR_LEN]; int status; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); if (!nn->rec_file || !test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; status = nfs4_make_rec_clidname(dname, &clp->cl_name); if (status) return legacy_recdir_name_error(clp, status); status = mnt_want_write_file(nn->rec_file); if (status) goto out; clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); status = nfs4_save_creds(&original_cred); if (status < 0) goto out_drop_write; status = nfsd4_unlink_clid_dir(dname, HEXDIR_LEN-1, nn); nfs4_reset_creds(original_cred); if (status == 0) { vfs_fsync(nn->rec_file, 0); if (nn->in_grace) { /* remove reclaim record */ crp = nfsd4_find_reclaim_client(dname, nn); if (crp) nfs4_remove_reclaim_record(crp, nn); } } out_drop_write: mnt_drop_write_file(nn->rec_file); out: if (status) printk("NFSD: Failed to remove expired client state directory" " %.*s\n", HEXDIR_LEN, dname); } static int purge_old(struct dentry *parent, struct dentry *child, struct nfsd_net *nn) { int status; if (nfs4_has_reclaimed_state(child->d_name.name, nn)) return 0; status = vfs_rmdir(parent->d_inode, child); if (status) printk("failed to remove client recovery directory %pd\n", child); /* Keep trying, success or failure: */ return 0; } static void nfsd4_recdir_purge_old(struct nfsd_net *nn) { int status; nn->in_grace = false; if (!nn->rec_file) return; status = mnt_want_write_file(nn->rec_file); if (status) goto out; status = nfsd4_list_rec_dir(purge_old, nn); if (status == 0) vfs_fsync(nn->rec_file, 0); mnt_drop_write_file(nn->rec_file); out: nfs4_release_reclaim(nn); if (status) printk("nfsd4: failed to purge old clients from recovery" " directory %pD\n", nn->rec_file); } static int load_recdir(struct dentry *parent, struct dentry *child, struct nfsd_net *nn) { if (child->d_name.len != HEXDIR_LEN - 1) { printk("nfsd4: illegal name %pd in recovery directory\n", child); /* Keep trying; maybe the others are OK: */ return 0; } nfs4_client_to_reclaim(child->d_name.name, nn); return 0; } static int nfsd4_recdir_load(struct net *net) { int status; struct nfsd_net *nn = net_generic(net, nfsd_net_id); if (!nn->rec_file) return 0; status = nfsd4_list_rec_dir(load_recdir, nn); if (status) printk("nfsd4: failed loading clients from recovery" " directory %pD\n", nn->rec_file); return status; } /* * Hold reference to the recovery directory. */ static int nfsd4_init_recdir(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); const struct cred *original_cred; int status; printk("NFSD: Using %s as the NFSv4 state recovery directory\n", user_recovery_dirname); BUG_ON(nn->rec_file); status = nfs4_save_creds(&original_cred); if (status < 0) { printk("NFSD: Unable to change credentials to find recovery" " directory: error %d\n", status); return status; } nn->rec_file = filp_open(user_recovery_dirname, O_RDONLY | O_DIRECTORY, 0); if (IS_ERR(nn->rec_file)) { printk("NFSD: unable to find recovery directory %s\n", user_recovery_dirname); status = PTR_ERR(nn->rec_file); nn->rec_file = NULL; } nfs4_reset_creds(original_cred); if (!status) nn->in_grace = true; return status; } static void nfsd4_shutdown_recdir(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); if (!nn->rec_file) return; fput(nn->rec_file); nn->rec_file = NULL; } static int nfs4_legacy_state_init(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); int i; nn->reclaim_str_hashtbl = kmalloc(sizeof(struct list_head) * CLIENT_HASH_SIZE, GFP_KERNEL); if (!nn->reclaim_str_hashtbl) return -ENOMEM; for (i = 0; i < CLIENT_HASH_SIZE; i++) INIT_LIST_HEAD(&nn->reclaim_str_hashtbl[i]); nn->reclaim_str_hashtbl_size = 0; return 0; } static void nfs4_legacy_state_shutdown(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); kfree(nn->reclaim_str_hashtbl); } static int nfsd4_load_reboot_recovery_data(struct net *net) { int status; status = nfsd4_init_recdir(net); if (status) return status; status = nfsd4_recdir_load(net); if (status) nfsd4_shutdown_recdir(net); return status; } static int nfsd4_legacy_tracking_init(struct net *net) { int status; /* XXX: The legacy code won't work in a container */ if (net != &init_net) { WARN(1, KERN_ERR "NFSD: attempt to initialize legacy client " "tracking in a container!\n"); return -EINVAL; } status = nfs4_legacy_state_init(net); if (status) return status; status = nfsd4_load_reboot_recovery_data(net); if (status) goto err; return 0; err: nfs4_legacy_state_shutdown(net); return status; } static void nfsd4_legacy_tracking_exit(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); nfs4_release_reclaim(nn); nfsd4_shutdown_recdir(net); nfs4_legacy_state_shutdown(net); } /* * Change the NFSv4 recovery directory to recdir. */ int nfs4_reset_recoverydir(char *recdir) { int status; struct path path; status = kern_path(recdir, LOOKUP_FOLLOW, &path); if (status) return status; status = -ENOTDIR; if (d_is_dir(path.dentry)) { strcpy(user_recovery_dirname, recdir); status = 0; } path_put(&path); return status; } char * nfs4_recoverydir(void) { return user_recovery_dirname; } static int nfsd4_check_legacy_client(struct nfs4_client *clp) { int status; char dname[HEXDIR_LEN]; struct nfs4_client_reclaim *crp; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); /* did we already find that this client is stable? */ if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return 0; status = nfs4_make_rec_clidname(dname, &clp->cl_name); if (status) { legacy_recdir_name_error(clp, status); return status; } /* look for it in the reclaim hashtable otherwise */ crp = nfsd4_find_reclaim_client(dname, nn); if (crp) { set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); crp->cr_clp = clp; return 0; } return -ENOENT; } static struct nfsd4_client_tracking_ops nfsd4_legacy_tracking_ops = { .init = nfsd4_legacy_tracking_init, .exit = nfsd4_legacy_tracking_exit, .create = nfsd4_create_clid_dir, .remove = nfsd4_remove_clid_dir, .check = nfsd4_check_legacy_client, .grace_done = nfsd4_recdir_purge_old, }; /* Globals */ #define NFSD_PIPE_DIR "nfsd" #define NFSD_CLD_PIPE "cld" /* per-net-ns structure for holding cld upcall info */ struct cld_net { struct rpc_pipe *cn_pipe; spinlock_t cn_lock; struct list_head cn_list; unsigned int cn_xid; }; struct cld_upcall { struct list_head cu_list; struct cld_net *cu_net; struct task_struct *cu_task; struct cld_msg cu_msg; }; static int __cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg) { int ret; struct rpc_pipe_msg msg; memset(&msg, 0, sizeof(msg)); msg.data = cmsg; msg.len = sizeof(*cmsg); /* * Set task state before we queue the upcall. That prevents * wake_up_process in the downcall from racing with schedule. */ set_current_state(TASK_UNINTERRUPTIBLE); ret = rpc_queue_upcall(pipe, &msg); if (ret < 0) { set_current_state(TASK_RUNNING); goto out; } schedule(); if (msg.errno < 0) ret = msg.errno; out: return ret; } static int cld_pipe_upcall(struct rpc_pipe *pipe, struct cld_msg *cmsg) { int ret; /* * -EAGAIN occurs when pipe is closed and reopened while there are * upcalls queued. */ do { ret = __cld_pipe_upcall(pipe, cmsg); } while (ret == -EAGAIN); return ret; } static ssize_t cld_pipe_downcall(struct file *filp, const char __user *src, size_t mlen) { struct cld_upcall *tmp, *cup; struct cld_msg __user *cmsg = (struct cld_msg __user *)src; uint32_t xid; struct nfsd_net *nn = net_generic(file_inode(filp)->i_sb->s_fs_info, nfsd_net_id); struct cld_net *cn = nn->cld_net; if (mlen != sizeof(*cmsg)) { dprintk("%s: got %zu bytes, expected %zu\n", __func__, mlen, sizeof(*cmsg)); return -EINVAL; } /* copy just the xid so we can try to find that */ if (copy_from_user(&xid, &cmsg->cm_xid, sizeof(xid)) != 0) { dprintk("%s: error when copying xid from userspace", __func__); return -EFAULT; } /* walk the list and find corresponding xid */ cup = NULL; spin_lock(&cn->cn_lock); list_for_each_entry(tmp, &cn->cn_list, cu_list) { if (get_unaligned(&tmp->cu_msg.cm_xid) == xid) { cup = tmp; list_del_init(&cup->cu_list); break; } } spin_unlock(&cn->cn_lock); /* couldn't find upcall? */ if (!cup) { dprintk("%s: couldn't find upcall -- xid=%u\n", __func__, xid); return -EINVAL; } if (copy_from_user(&cup->cu_msg, src, mlen) != 0) return -EFAULT; wake_up_process(cup->cu_task); return mlen; } static void cld_pipe_destroy_msg(struct rpc_pipe_msg *msg) { struct cld_msg *cmsg = msg->data; struct cld_upcall *cup = container_of(cmsg, struct cld_upcall, cu_msg); /* errno >= 0 means we got a downcall */ if (msg->errno >= 0) return; wake_up_process(cup->cu_task); } static const struct rpc_pipe_ops cld_upcall_ops = { .upcall = rpc_pipe_generic_upcall, .downcall = cld_pipe_downcall, .destroy_msg = cld_pipe_destroy_msg, }; static struct dentry * nfsd4_cld_register_sb(struct super_block *sb, struct rpc_pipe *pipe) { struct dentry *dir, *dentry; dir = rpc_d_lookup_sb(sb, NFSD_PIPE_DIR); if (dir == NULL) return ERR_PTR(-ENOENT); dentry = rpc_mkpipe_dentry(dir, NFSD_CLD_PIPE, NULL, pipe); dput(dir); return dentry; } static void nfsd4_cld_unregister_sb(struct rpc_pipe *pipe) { if (pipe->dentry) rpc_unlink(pipe->dentry); } static struct dentry * nfsd4_cld_register_net(struct net *net, struct rpc_pipe *pipe) { struct super_block *sb; struct dentry *dentry; sb = rpc_get_sb_net(net); if (!sb) return NULL; dentry = nfsd4_cld_register_sb(sb, pipe); rpc_put_sb_net(net); return dentry; } static void nfsd4_cld_unregister_net(struct net *net, struct rpc_pipe *pipe) { struct super_block *sb; sb = rpc_get_sb_net(net); if (sb) { nfsd4_cld_unregister_sb(pipe); rpc_put_sb_net(net); } } /* Initialize rpc_pipefs pipe for communication with client tracking daemon */ static int nfsd4_init_cld_pipe(struct net *net) { int ret; struct dentry *dentry; struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct cld_net *cn; if (nn->cld_net) return 0; cn = kzalloc(sizeof(*cn), GFP_KERNEL); if (!cn) { ret = -ENOMEM; goto err; } cn->cn_pipe = rpc_mkpipe_data(&cld_upcall_ops, RPC_PIPE_WAIT_FOR_OPEN); if (IS_ERR(cn->cn_pipe)) { ret = PTR_ERR(cn->cn_pipe); goto err; } spin_lock_init(&cn->cn_lock); INIT_LIST_HEAD(&cn->cn_list); dentry = nfsd4_cld_register_net(net, cn->cn_pipe); if (IS_ERR(dentry)) { ret = PTR_ERR(dentry); goto err_destroy_data; } cn->cn_pipe->dentry = dentry; nn->cld_net = cn; return 0; err_destroy_data: rpc_destroy_pipe_data(cn->cn_pipe); err: kfree(cn); printk(KERN_ERR "NFSD: unable to create nfsdcld upcall pipe (%d)\n", ret); return ret; } static void nfsd4_remove_cld_pipe(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct cld_net *cn = nn->cld_net; nfsd4_cld_unregister_net(net, cn->cn_pipe); rpc_destroy_pipe_data(cn->cn_pipe); kfree(nn->cld_net); nn->cld_net = NULL; } static struct cld_upcall * alloc_cld_upcall(struct cld_net *cn) { struct cld_upcall *new, *tmp; new = kzalloc(sizeof(*new), GFP_KERNEL); if (!new) return new; /* FIXME: hard cap on number in flight? */ restart_search: spin_lock(&cn->cn_lock); list_for_each_entry(tmp, &cn->cn_list, cu_list) { if (tmp->cu_msg.cm_xid == cn->cn_xid) { cn->cn_xid++; spin_unlock(&cn->cn_lock); goto restart_search; } } new->cu_task = current; new->cu_msg.cm_vers = CLD_UPCALL_VERSION; put_unaligned(cn->cn_xid++, &new->cu_msg.cm_xid); new->cu_net = cn; list_add(&new->cu_list, &cn->cn_list); spin_unlock(&cn->cn_lock); dprintk("%s: allocated xid %u\n", __func__, new->cu_msg.cm_xid); return new; } static void free_cld_upcall(struct cld_upcall *victim) { struct cld_net *cn = victim->cu_net; spin_lock(&cn->cn_lock); list_del(&victim->cu_list); spin_unlock(&cn->cn_lock); kfree(victim); } /* Ask daemon to create a new record */ static void nfsd4_cld_create(struct nfs4_client *clp) { int ret; struct cld_upcall *cup; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); struct cld_net *cn = nn->cld_net; /* Don't upcall if it's already stored */ if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; cup = alloc_cld_upcall(cn); if (!cup) { ret = -ENOMEM; goto out_err; } cup->cu_msg.cm_cmd = Cld_Create; cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, clp->cl_name.len); ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); if (!ret) { ret = cup->cu_msg.cm_status; set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); } free_cld_upcall(cup); out_err: if (ret) printk(KERN_ERR "NFSD: Unable to create client " "record on stable storage: %d\n", ret); } /* Ask daemon to create a new record */ static void nfsd4_cld_remove(struct nfs4_client *clp) { int ret; struct cld_upcall *cup; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); struct cld_net *cn = nn->cld_net; /* Don't upcall if it's already removed */ if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; cup = alloc_cld_upcall(cn); if (!cup) { ret = -ENOMEM; goto out_err; } cup->cu_msg.cm_cmd = Cld_Remove; cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, clp->cl_name.len); ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); if (!ret) { ret = cup->cu_msg.cm_status; clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); } free_cld_upcall(cup); out_err: if (ret) printk(KERN_ERR "NFSD: Unable to remove client " "record from stable storage: %d\n", ret); } /* Check for presence of a record, and update its timestamp */ static int nfsd4_cld_check(struct nfs4_client *clp) { int ret; struct cld_upcall *cup; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); struct cld_net *cn = nn->cld_net; /* Don't upcall if one was already stored during this grace pd */ if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return 0; cup = alloc_cld_upcall(cn); if (!cup) { printk(KERN_ERR "NFSD: Unable to check client record on " "stable storage: %d\n", -ENOMEM); return -ENOMEM; } cup->cu_msg.cm_cmd = Cld_Check; cup->cu_msg.cm_u.cm_name.cn_len = clp->cl_name.len; memcpy(cup->cu_msg.cm_u.cm_name.cn_id, clp->cl_name.data, clp->cl_name.len); ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); if (!ret) { ret = cup->cu_msg.cm_status; set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); } free_cld_upcall(cup); return ret; } static void nfsd4_cld_grace_done(struct nfsd_net *nn) { int ret; struct cld_upcall *cup; struct cld_net *cn = nn->cld_net; cup = alloc_cld_upcall(cn); if (!cup) { ret = -ENOMEM; goto out_err; } cup->cu_msg.cm_cmd = Cld_GraceDone; cup->cu_msg.cm_u.cm_gracetime = (int64_t)nn->boot_time; ret = cld_pipe_upcall(cn->cn_pipe, &cup->cu_msg); if (!ret) ret = cup->cu_msg.cm_status; free_cld_upcall(cup); out_err: if (ret) printk(KERN_ERR "NFSD: Unable to end grace period: %d\n", ret); } static struct nfsd4_client_tracking_ops nfsd4_cld_tracking_ops = { .init = nfsd4_init_cld_pipe, .exit = nfsd4_remove_cld_pipe, .create = nfsd4_cld_create, .remove = nfsd4_cld_remove, .check = nfsd4_cld_check, .grace_done = nfsd4_cld_grace_done, }; /* upcall via usermodehelper */ static char cltrack_prog[PATH_MAX] = "/sbin/nfsdcltrack"; module_param_string(cltrack_prog, cltrack_prog, sizeof(cltrack_prog), S_IRUGO|S_IWUSR); MODULE_PARM_DESC(cltrack_prog, "Path to the nfsdcltrack upcall program"); static bool cltrack_legacy_disable; module_param(cltrack_legacy_disable, bool, S_IRUGO|S_IWUSR); MODULE_PARM_DESC(cltrack_legacy_disable, "Disable legacy recoverydir conversion. Default: false"); #define LEGACY_TOPDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_TOPDIR=" #define LEGACY_RECDIR_ENV_PREFIX "NFSDCLTRACK_LEGACY_RECDIR=" #define HAS_SESSION_ENV_PREFIX "NFSDCLTRACK_CLIENT_HAS_SESSION=" #define GRACE_START_ENV_PREFIX "NFSDCLTRACK_GRACE_START=" static char * nfsd4_cltrack_legacy_topdir(void) { int copied; size_t len; char *result; if (cltrack_legacy_disable) return NULL; len = strlen(LEGACY_TOPDIR_ENV_PREFIX) + strlen(nfs4_recoverydir()) + 1; result = kmalloc(len, GFP_KERNEL); if (!result) return result; copied = snprintf(result, len, LEGACY_TOPDIR_ENV_PREFIX "%s", nfs4_recoverydir()); if (copied >= len) { /* just return nothing if output was truncated */ kfree(result); return NULL; } return result; } static char * nfsd4_cltrack_legacy_recdir(const struct xdr_netobj *name) { int copied; size_t len; char *result; if (cltrack_legacy_disable) return NULL; /* +1 is for '/' between "topdir" and "recdir" */ len = strlen(LEGACY_RECDIR_ENV_PREFIX) + strlen(nfs4_recoverydir()) + 1 + HEXDIR_LEN; result = kmalloc(len, GFP_KERNEL); if (!result) return result; copied = snprintf(result, len, LEGACY_RECDIR_ENV_PREFIX "%s/", nfs4_recoverydir()); if (copied > (len - HEXDIR_LEN)) { /* just return nothing if output will be truncated */ kfree(result); return NULL; } copied = nfs4_make_rec_clidname(result + copied, name); if (copied) { kfree(result); return NULL; } return result; } static char * nfsd4_cltrack_client_has_session(struct nfs4_client *clp) { int copied; size_t len; char *result; /* prefix + Y/N character + terminating NULL */ len = strlen(HAS_SESSION_ENV_PREFIX) + 1 + 1; result = kmalloc(len, GFP_KERNEL); if (!result) return result; copied = snprintf(result, len, HAS_SESSION_ENV_PREFIX "%c", clp->cl_minorversion ? 'Y' : 'N'); if (copied >= len) { /* just return nothing if output was truncated */ kfree(result); return NULL; } return result; } static char * nfsd4_cltrack_grace_start(time_t grace_start) { int copied; size_t len; char *result; /* prefix + max width of int64_t string + terminating NULL */ len = strlen(GRACE_START_ENV_PREFIX) + 22 + 1; result = kmalloc(len, GFP_KERNEL); if (!result) return result; copied = snprintf(result, len, GRACE_START_ENV_PREFIX "%ld", grace_start); if (copied >= len) { /* just return nothing if output was truncated */ kfree(result); return NULL; } return result; } static int nfsd4_umh_cltrack_upcall(char *cmd, char *arg, char *env0, char *env1) { char *envp[3]; char *argv[4]; int ret; if (unlikely(!cltrack_prog[0])) { dprintk("%s: cltrack_prog is disabled\n", __func__); return -EACCES; } dprintk("%s: cmd: %s\n", __func__, cmd); dprintk("%s: arg: %s\n", __func__, arg ? arg : "(null)"); dprintk("%s: env0: %s\n", __func__, env0 ? env0 : "(null)"); dprintk("%s: env1: %s\n", __func__, env1 ? env1 : "(null)"); envp[0] = env0; envp[1] = env1; envp[2] = NULL; argv[0] = (char *)cltrack_prog; argv[1] = cmd; argv[2] = arg; argv[3] = NULL; ret = call_usermodehelper(argv[0], argv, envp, UMH_WAIT_PROC); /* * Disable the upcall mechanism if we're getting an ENOENT or EACCES * error. The admin can re-enable it on the fly by using sysfs * once the problem has been fixed. */ if (ret == -ENOENT || ret == -EACCES) { dprintk("NFSD: %s was not found or isn't executable (%d). " "Setting cltrack_prog to blank string!", cltrack_prog, ret); cltrack_prog[0] = '\0'; } dprintk("%s: %s return value: %d\n", __func__, cltrack_prog, ret); return ret; } static char * bin_to_hex_dup(const unsigned char *src, int srclen) { int i; char *buf, *hex; /* +1 for terminating NULL */ buf = kmalloc((srclen * 2) + 1, GFP_KERNEL); if (!buf) return buf; hex = buf; for (i = 0; i < srclen; i++) { sprintf(hex, "%2.2x", *src++); hex += 2; } return buf; } static int nfsd4_umh_cltrack_init(struct net *net) { int ret; struct nfsd_net *nn = net_generic(net, nfsd_net_id); char *grace_start = nfsd4_cltrack_grace_start(nn->boot_time); /* XXX: The usermode helper s not working in container yet. */ if (net != &init_net) { WARN(1, KERN_ERR "NFSD: attempt to initialize umh client " "tracking in a container!\n"); return -EINVAL; } ret = nfsd4_umh_cltrack_upcall("init", NULL, grace_start, NULL); kfree(grace_start); return ret; } static void nfsd4_cltrack_upcall_lock(struct nfs4_client *clp) { wait_on_bit_lock(&clp->cl_flags, NFSD4_CLIENT_UPCALL_LOCK, TASK_UNINTERRUPTIBLE); } static void nfsd4_cltrack_upcall_unlock(struct nfs4_client *clp) { smp_mb__before_atomic(); clear_bit(NFSD4_CLIENT_UPCALL_LOCK, &clp->cl_flags); smp_mb__after_atomic(); wake_up_bit(&clp->cl_flags, NFSD4_CLIENT_UPCALL_LOCK); } static void nfsd4_umh_cltrack_create(struct nfs4_client *clp) { char *hexid, *has_session, *grace_start; struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); /* * With v4.0 clients, there's little difference in outcome between a * create and check operation, and we can end up calling into this * function multiple times per client (once for each openowner). So, * for v4.0 clients skip upcalling once the client has been recorded * on stable storage. * * For v4.1+ clients, the outcome of the two operations is different, * so we must ensure that we upcall for the create operation. v4.1+ * clients call this on RECLAIM_COMPLETE though, so we should only end * up doing a single create upcall per client. */ if (clp->cl_minorversion == 0 && test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len); if (!hexid) { dprintk("%s: can't allocate memory for upcall!\n", __func__); return; } has_session = nfsd4_cltrack_client_has_session(clp); grace_start = nfsd4_cltrack_grace_start(nn->boot_time); nfsd4_cltrack_upcall_lock(clp); if (!nfsd4_umh_cltrack_upcall("create", hexid, has_session, grace_start)) set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); nfsd4_cltrack_upcall_unlock(clp); kfree(has_session); kfree(grace_start); kfree(hexid); } static void nfsd4_umh_cltrack_remove(struct nfs4_client *clp) { char *hexid; if (!test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return; hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len); if (!hexid) { dprintk("%s: can't allocate memory for upcall!\n", __func__); return; } nfsd4_cltrack_upcall_lock(clp); if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags) && nfsd4_umh_cltrack_upcall("remove", hexid, NULL, NULL) == 0) clear_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); nfsd4_cltrack_upcall_unlock(clp); kfree(hexid); } static int nfsd4_umh_cltrack_check(struct nfs4_client *clp) { int ret; char *hexid, *has_session, *legacy; if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) return 0; hexid = bin_to_hex_dup(clp->cl_name.data, clp->cl_name.len); if (!hexid) { dprintk("%s: can't allocate memory for upcall!\n", __func__); return -ENOMEM; } has_session = nfsd4_cltrack_client_has_session(clp); legacy = nfsd4_cltrack_legacy_recdir(&clp->cl_name); nfsd4_cltrack_upcall_lock(clp); if (test_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags)) { ret = 0; } else { ret = nfsd4_umh_cltrack_upcall("check", hexid, has_session, legacy); if (ret == 0) set_bit(NFSD4_CLIENT_STABLE, &clp->cl_flags); } nfsd4_cltrack_upcall_unlock(clp); kfree(has_session); kfree(legacy); kfree(hexid); return ret; } static void nfsd4_umh_cltrack_grace_done(struct nfsd_net *nn) { char *legacy; char timestr[22]; /* FIXME: better way to determine max size? */ sprintf(timestr, "%ld", nn->boot_time); legacy = nfsd4_cltrack_legacy_topdir(); nfsd4_umh_cltrack_upcall("gracedone", timestr, legacy, NULL); kfree(legacy); } static struct nfsd4_client_tracking_ops nfsd4_umh_tracking_ops = { .init = nfsd4_umh_cltrack_init, .exit = NULL, .create = nfsd4_umh_cltrack_create, .remove = nfsd4_umh_cltrack_remove, .check = nfsd4_umh_cltrack_check, .grace_done = nfsd4_umh_cltrack_grace_done, }; int nfsd4_client_tracking_init(struct net *net) { int status; struct path path; struct nfsd_net *nn = net_generic(net, nfsd_net_id); /* just run the init if it the method is already decided */ if (nn->client_tracking_ops) goto do_init; /* * First, try a UMH upcall. It should succeed or fail quickly, so * there's little harm in trying that first. */ nn->client_tracking_ops = &nfsd4_umh_tracking_ops; status = nn->client_tracking_ops->init(net); if (!status) return status; /* * See if the recoverydir exists and is a directory. If it is, * then use the legacy ops. */ nn->client_tracking_ops = &nfsd4_legacy_tracking_ops; status = kern_path(nfs4_recoverydir(), LOOKUP_FOLLOW, &path); if (!status) { status = d_is_dir(path.dentry); path_put(&path); if (status) goto do_init; } /* Finally, try to use nfsdcld */ nn->client_tracking_ops = &nfsd4_cld_tracking_ops; printk(KERN_WARNING "NFSD: the nfsdcld client tracking upcall will be " "removed in 3.10. Please transition to using " "nfsdcltrack.\n"); do_init: status = nn->client_tracking_ops->init(net); if (status) { printk(KERN_WARNING "NFSD: Unable to initialize client " "recovery tracking! (%d)\n", status); nn->client_tracking_ops = NULL; } return status; } void nfsd4_client_tracking_exit(struct net *net) { struct nfsd_net *nn = net_generic(net, nfsd_net_id); if (nn->client_tracking_ops) { if (nn->client_tracking_ops->exit) nn->client_tracking_ops->exit(net); nn->client_tracking_ops = NULL; } } void nfsd4_client_record_create(struct nfs4_client *clp) { struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); if (nn->client_tracking_ops) nn->client_tracking_ops->create(clp); } void nfsd4_client_record_remove(struct nfs4_client *clp) { struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); if (nn->client_tracking_ops) nn->client_tracking_ops->remove(clp); } int nfsd4_client_record_check(struct nfs4_client *clp) { struct nfsd_net *nn = net_generic(clp->net, nfsd_net_id); if (nn->client_tracking_ops) return nn->client_tracking_ops->check(clp); return -EOPNOTSUPP; } void nfsd4_record_grace_done(struct nfsd_net *nn) { if (nn->client_tracking_ops) nn->client_tracking_ops->grace_done(nn); } static int rpc_pipefs_event(struct notifier_block *nb, unsigned long event, void *ptr) { struct super_block *sb = ptr; struct net *net = sb->s_fs_info; struct nfsd_net *nn = net_generic(net, nfsd_net_id); struct cld_net *cn = nn->cld_net; struct dentry *dentry; int ret = 0; if (!try_module_get(THIS_MODULE)) return 0; if (!cn) { module_put(THIS_MODULE); return 0; } switch (event) { case RPC_PIPEFS_MOUNT: dentry = nfsd4_cld_register_sb(sb, cn->cn_pipe); if (IS_ERR(dentry)) { ret = PTR_ERR(dentry); break; } cn->cn_pipe->dentry = dentry; break; case RPC_PIPEFS_UMOUNT: if (cn->cn_pipe->dentry) nfsd4_cld_unregister_sb(cn->cn_pipe); break; default: ret = -ENOTSUPP; break; } module_put(THIS_MODULE); return ret; } static struct notifier_block nfsd4_cld_block = { .notifier_call = rpc_pipefs_event, }; int register_cld_notifier(void) { return rpc_pipefs_notifier_register(&nfsd4_cld_block); } void unregister_cld_notifier(void) { rpc_pipefs_notifier_unregister(&nfsd4_cld_block); }