diff options
Diffstat (limited to 'fs/smb/server/mgmt/share_config.c')
| -rw-r--r-- | fs/smb/server/mgmt/share_config.c | 234 |
1 files changed, 234 insertions, 0 deletions
diff --git a/fs/smb/server/mgmt/share_config.c b/fs/smb/server/mgmt/share_config.c new file mode 100644 index 000000000..328a41225 --- /dev/null +++ b/fs/smb/server/mgmt/share_config.c @@ -0,0 +1,234 @@ +// SPDX-License-Identifier: GPL-2.0-or-later +/* + * Copyright (C) 2018 Samsung Electronics Co., Ltd. + */ + +#include <linux/list.h> +#include <linux/jhash.h> +#include <linux/slab.h> +#include <linux/rwsem.h> +#include <linux/parser.h> +#include <linux/namei.h> +#include <linux/sched.h> +#include <linux/mm.h> + +#include "share_config.h" +#include "user_config.h" +#include "user_session.h" +#include "../transport_ipc.h" +#include "../misc.h" + +#define SHARE_HASH_BITS 3 +static DEFINE_HASHTABLE(shares_table, SHARE_HASH_BITS); +static DECLARE_RWSEM(shares_table_lock); + +struct ksmbd_veto_pattern { + char *pattern; + struct list_head list; +}; + +static unsigned int share_name_hash(const char *name) +{ + return jhash(name, strlen(name), 0); +} + +static void kill_share(struct ksmbd_share_config *share) +{ + while (!list_empty(&share->veto_list)) { + struct ksmbd_veto_pattern *p; + + p = list_entry(share->veto_list.next, + struct ksmbd_veto_pattern, + list); + list_del(&p->list); + kfree(p->pattern); + kfree(p); + } + + if (share->path) + path_put(&share->vfs_path); + kfree(share->name); + kfree(share->path); + kfree(share); +} + +void ksmbd_share_config_del(struct ksmbd_share_config *share) +{ + down_write(&shares_table_lock); + hash_del(&share->hlist); + up_write(&shares_table_lock); +} + +void __ksmbd_share_config_put(struct ksmbd_share_config *share) +{ + ksmbd_share_config_del(share); + kill_share(share); +} + +static struct ksmbd_share_config * +__get_share_config(struct ksmbd_share_config *share) +{ + if (!atomic_inc_not_zero(&share->refcount)) + return NULL; + return share; +} + +static struct ksmbd_share_config *__share_lookup(const char *name) +{ + struct ksmbd_share_config *share; + unsigned int key = share_name_hash(name); + + hash_for_each_possible(shares_table, share, hlist, key) { + if (!strcmp(name, share->name)) + return share; + } + return NULL; +} + +static int parse_veto_list(struct ksmbd_share_config *share, + char *veto_list, + int veto_list_sz) +{ + int sz = 0; + + if (!veto_list_sz) + return 0; + + while (veto_list_sz > 0) { + struct ksmbd_veto_pattern *p; + + sz = strlen(veto_list); + if (!sz) + break; + + p = kzalloc(sizeof(struct ksmbd_veto_pattern), GFP_KERNEL); + if (!p) + return -ENOMEM; + + p->pattern = kstrdup(veto_list, GFP_KERNEL); + if (!p->pattern) { + kfree(p); + return -ENOMEM; + } + + list_add(&p->list, &share->veto_list); + + veto_list += sz + 1; + veto_list_sz -= (sz + 1); + } + + return 0; +} + +static struct ksmbd_share_config *share_config_request(struct unicode_map *um, + const char *name) +{ + struct ksmbd_share_config_response *resp; + struct ksmbd_share_config *share = NULL; + struct ksmbd_share_config *lookup; + int ret; + + resp = ksmbd_ipc_share_config_request(name); + if (!resp) + return NULL; + + if (resp->flags == KSMBD_SHARE_FLAG_INVALID) + goto out; + + if (*resp->share_name) { + char *cf_resp_name; + bool equal; + + cf_resp_name = ksmbd_casefold_sharename(um, resp->share_name); + if (IS_ERR(cf_resp_name)) + goto out; + equal = !strcmp(cf_resp_name, name); + kfree(cf_resp_name); + if (!equal) + goto out; + } + + share = kzalloc(sizeof(struct ksmbd_share_config), GFP_KERNEL); + if (!share) + goto out; + + share->flags = resp->flags; + atomic_set(&share->refcount, 1); + INIT_LIST_HEAD(&share->veto_list); + share->name = kstrdup(name, GFP_KERNEL); + + if (!test_share_config_flag(share, KSMBD_SHARE_FLAG_PIPE)) { + share->path = kstrdup(ksmbd_share_config_path(resp), + GFP_KERNEL); + if (share->path) + share->path_sz = strlen(share->path); + share->create_mask = resp->create_mask; + share->directory_mask = resp->directory_mask; + share->force_create_mode = resp->force_create_mode; + share->force_directory_mode = resp->force_directory_mode; + share->force_uid = resp->force_uid; + share->force_gid = resp->force_gid; + ret = parse_veto_list(share, + KSMBD_SHARE_CONFIG_VETO_LIST(resp), + resp->veto_list_sz); + if (!ret && share->path) { + ret = kern_path(share->path, 0, &share->vfs_path); + if (ret) { + ksmbd_debug(SMB, "failed to access '%s'\n", + share->path); + /* Avoid put_path() */ + kfree(share->path); + share->path = NULL; + } + } + if (ret || !share->name) { + kill_share(share); + share = NULL; + goto out; + } + } + + down_write(&shares_table_lock); + lookup = __share_lookup(name); + if (lookup) + lookup = __get_share_config(lookup); + if (!lookup) { + hash_add(shares_table, &share->hlist, share_name_hash(name)); + } else { + kill_share(share); + share = lookup; + } + up_write(&shares_table_lock); + +out: + kvfree(resp); + return share; +} + +struct ksmbd_share_config *ksmbd_share_config_get(struct unicode_map *um, + const char *name) +{ + struct ksmbd_share_config *share; + + down_read(&shares_table_lock); + share = __share_lookup(name); + if (share) + share = __get_share_config(share); + up_read(&shares_table_lock); + + if (share) + return share; + return share_config_request(um, name); +} + +bool ksmbd_share_veto_filename(struct ksmbd_share_config *share, + const char *filename) +{ + struct ksmbd_veto_pattern *p; + + list_for_each_entry(p, &share->veto_list, list) { + if (match_wildcard(p->pattern, filename)) + return true; + } + return false; +} |