diff --git a/fs/ceph/Kconfig b/fs/ceph/Kconfig index 7f7d92d6b024..cf235f6eacf9 100644 --- a/fs/ceph/Kconfig +++ b/fs/ceph/Kconfig @@ -36,3 +36,15 @@ config CEPH_FS_POSIX_ACL groups beyond the owner/group/world scheme. If you don't know what Access Control Lists are, say N + +config CEPH_FS_SECURITY_LABEL + bool "CephFS Security Labels" + depends on CEPH_FS && SECURITY + help + Security labels support alternative access control models + implemented by security modules like SELinux. This option + enables an extended attribute handler for file security + labels in the Ceph filesystem. + + If you are not using a security module that requires using + extended attributes for file security labels, say N. diff --git a/fs/ceph/caps.c b/fs/ceph/caps.c index 7754d7679122..50409d9fdc90 100644 --- a/fs/ceph/caps.c +++ b/fs/ceph/caps.c @@ -3156,6 +3156,7 @@ static void handle_cap_grant(struct inode *inode, ci->i_xattrs.blob = ceph_buffer_get(xattr_buf); ci->i_xattrs.version = version; ceph_forget_all_cached_acls(inode); + ceph_security_invalidate_secctx(inode); } } diff --git a/fs/ceph/dir.c b/fs/ceph/dir.c index 14d795e5fa73..aab29f48c62d 100644 --- a/fs/ceph/dir.c +++ b/fs/ceph/dir.c @@ -837,6 +837,9 @@ static int ceph_mknod(struct inode *dir, struct dentry *dentry, } err = ceph_pre_init_acls(dir, &mode, &as_ctx); + if (err < 0) + goto out; + err = ceph_security_init_secctx(dentry, mode, &as_ctx); if (err < 0) goto out; @@ -884,6 +887,7 @@ static int ceph_symlink(struct inode *dir, struct dentry *dentry, struct ceph_fs_client *fsc = ceph_sb_to_client(dir->i_sb); struct ceph_mds_client *mdsc = fsc->mdsc; struct ceph_mds_request *req; + struct ceph_acl_sec_ctx as_ctx = {}; int err; if (ceph_snap(dir) != CEPH_NOSNAP) @@ -894,6 +898,10 @@ static int ceph_symlink(struct inode *dir, struct dentry *dentry, goto out; } + err = ceph_security_init_secctx(dentry, S_IFLNK | 0777, &as_ctx); + if (err < 0) + goto out; + dout("symlink in dir %p dentry %p to '%s'\n", dir, dentry, dest); req = ceph_mdsc_create_request(mdsc, CEPH_MDS_OP_SYMLINK, USE_AUTH_MDS); if (IS_ERR(req)) { @@ -919,6 +927,7 @@ static int ceph_symlink(struct inode *dir, struct dentry *dentry, out: if (err) d_drop(dentry); + ceph_release_acl_sec_ctx(&as_ctx); return err; } @@ -951,6 +960,9 @@ static int ceph_mkdir(struct inode *dir, struct dentry *dentry, umode_t mode) mode |= S_IFDIR; err = ceph_pre_init_acls(dir, &mode, &as_ctx); + if (err < 0) + goto out; + err = ceph_security_init_secctx(dentry, mode, &as_ctx); if (err < 0) goto out; diff --git a/fs/ceph/file.c b/fs/ceph/file.c index 455b2a50d9c3..d616e4b50b57 100644 --- a/fs/ceph/file.c +++ b/fs/ceph/file.c @@ -454,6 +454,9 @@ int ceph_atomic_open(struct inode *dir, struct dentry *dentry, err = ceph_pre_init_acls(dir, &mode, &as_ctx); if (err < 0) return err; + err = ceph_security_init_secctx(dentry, mode, &as_ctx); + if (err < 0) + goto out_ctx; } /* do the open */ diff --git a/fs/ceph/inode.c b/fs/ceph/inode.c index 18869ba08db7..b2988e9f8e15 100644 --- a/fs/ceph/inode.c +++ b/fs/ceph/inode.c @@ -888,6 +888,7 @@ static int fill_inode(struct inode *inode, struct page *locked_page, iinfo->xattr_data, iinfo->xattr_len); ci->i_xattrs.version = le64_to_cpu(info->xattr_version); ceph_forget_all_cached_acls(inode); + ceph_security_invalidate_secctx(inode); xattr_blob = NULL; } diff --git a/fs/ceph/super.h b/fs/ceph/super.h index f82fd186eb8a..81bbb197fc3c 100644 --- a/fs/ceph/super.h +++ b/fs/ceph/super.h @@ -933,6 +933,10 @@ struct ceph_acl_sec_ctx { #ifdef CONFIG_CEPH_FS_POSIX_ACL void *default_acl; void *acl; +#endif +#ifdef CONFIG_CEPH_FS_SECURITY_LABEL + void *sec_ctx; + u32 sec_ctxlen; #endif struct ceph_pagelist *pagelist; }; @@ -951,6 +955,21 @@ static inline bool ceph_security_xattr_wanted(struct inode *in) } #endif +#ifdef CONFIG_CEPH_FS_SECURITY_LABEL +extern int ceph_security_init_secctx(struct dentry *dentry, umode_t mode, + struct ceph_acl_sec_ctx *ctx); +extern void ceph_security_invalidate_secctx(struct inode *inode); +#else +static inline int ceph_security_init_secctx(struct dentry *dentry, umode_t mode, + struct ceph_acl_sec_ctx *ctx) +{ + return 0; +} +static inline void ceph_security_invalidate_secctx(struct inode *inode) +{ +} +#endif + void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx); /* acl.c */ diff --git a/fs/ceph/xattr.c b/fs/ceph/xattr.c index 518a5beed58c..6621d27e64f5 100644 --- a/fs/ceph/xattr.c +++ b/fs/ceph/xattr.c @@ -8,6 +8,7 @@ #include #include +#include #include #include @@ -17,26 +18,9 @@ static int __remove_xattr(struct ceph_inode_info *ci, struct ceph_inode_xattr *xattr); -static const struct xattr_handler ceph_other_xattr_handler; - -/* - * List of handlers for synthetic system.* attributes. Other - * attributes are handled directly. - */ -const struct xattr_handler *ceph_xattr_handlers[] = { -#ifdef CONFIG_CEPH_FS_POSIX_ACL - &posix_acl_access_xattr_handler, - &posix_acl_default_xattr_handler, -#endif - &ceph_other_xattr_handler, - NULL, -}; - static bool ceph_is_valid_xattr(const char *name) { return !strncmp(name, XATTR_CEPH_PREFIX, XATTR_CEPH_PREFIX_LEN) || - !strncmp(name, XATTR_SECURITY_PREFIX, - XATTR_SECURITY_PREFIX_LEN) || !strncmp(name, XATTR_TRUSTED_PREFIX, XATTR_TRUSTED_PREFIX_LEN) || !strncmp(name, XATTR_USER_PREFIX, XATTR_USER_PREFIX_LEN); } @@ -1196,6 +1180,111 @@ bool ceph_security_xattr_deadlock(struct inode *in) spin_unlock(&ci->i_ceph_lock); return ret; } + +#ifdef CONFIG_CEPH_FS_SECURITY_LABEL +int ceph_security_init_secctx(struct dentry *dentry, umode_t mode, + struct ceph_acl_sec_ctx *as_ctx) +{ + struct ceph_pagelist *pagelist = as_ctx->pagelist; + const char *name; + size_t name_len; + int err; + + err = security_dentry_init_security(dentry, mode, &dentry->d_name, + &as_ctx->sec_ctx, + &as_ctx->sec_ctxlen); + if (err < 0) { + WARN_ON_ONCE(err != -EOPNOTSUPP); + err = 0; /* do nothing */ + goto out; + } + + err = -ENOMEM; + if (!pagelist) { + pagelist = ceph_pagelist_alloc(GFP_KERNEL); + if (!pagelist) + goto out; + err = ceph_pagelist_reserve(pagelist, PAGE_SIZE); + if (err) + goto out; + ceph_pagelist_encode_32(pagelist, 1); + } + + /* + * FIXME: Make security_dentry_init_security() generic. Currently + * It only supports single security module and only selinux has + * dentry_init_security hook. + */ + name = XATTR_NAME_SELINUX; + name_len = strlen(name); + err = ceph_pagelist_reserve(pagelist, + 4 * 2 + name_len + as_ctx->sec_ctxlen); + if (err) + goto out; + + if (as_ctx->pagelist) { + /* update count of KV pairs */ + BUG_ON(pagelist->length <= sizeof(__le32)); + if (list_is_singular(&pagelist->head)) { + le32_add_cpu((__le32*)pagelist->mapped_tail, 1); + } else { + struct page *page = list_first_entry(&pagelist->head, + struct page, lru); + void *addr = kmap_atomic(page); + le32_add_cpu((__le32*)addr, 1); + kunmap_atomic(addr); + } + } else { + as_ctx->pagelist = pagelist; + } + + ceph_pagelist_encode_32(pagelist, name_len); + ceph_pagelist_append(pagelist, name, name_len); + + ceph_pagelist_encode_32(pagelist, as_ctx->sec_ctxlen); + ceph_pagelist_append(pagelist, as_ctx->sec_ctx, as_ctx->sec_ctxlen); + + err = 0; +out: + if (pagelist && !as_ctx->pagelist) + ceph_pagelist_release(pagelist); + return err; +} + +void ceph_security_invalidate_secctx(struct inode *inode) +{ + security_inode_invalidate_secctx(inode); +} + +static int ceph_xattr_set_security_label(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *key, const void *buf, + size_t buflen, int flags) +{ + if (security_ismaclabel(key)) { + const char *name = xattr_full_name(handler, key); + return __ceph_setxattr(inode, name, buf, buflen, flags); + } + return -EOPNOTSUPP; +} + +static int ceph_xattr_get_security_label(const struct xattr_handler *handler, + struct dentry *unused, struct inode *inode, + const char *key, void *buf, size_t buflen) +{ + if (security_ismaclabel(key)) { + const char *name = xattr_full_name(handler, key); + return __ceph_getxattr(inode, name, buf, buflen); + } + return -EOPNOTSUPP; +} + +static const struct xattr_handler ceph_security_label_handler = { + .prefix = XATTR_SECURITY_PREFIX, + .get = ceph_xattr_get_security_label, + .set = ceph_xattr_set_security_label, +}; +#endif #endif void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx) @@ -1203,7 +1292,26 @@ void ceph_release_acl_sec_ctx(struct ceph_acl_sec_ctx *as_ctx) #ifdef CONFIG_CEPH_FS_POSIX_ACL posix_acl_release(as_ctx->acl); posix_acl_release(as_ctx->default_acl); +#endif +#ifdef CONFIG_CEPH_FS_SECURITY_LABEL + security_release_secctx(as_ctx->sec_ctx, as_ctx->sec_ctxlen); #endif if (as_ctx->pagelist) ceph_pagelist_release(as_ctx->pagelist); } + +/* + * List of handlers for synthetic system.* attributes. Other + * attributes are handled directly. + */ +const struct xattr_handler *ceph_xattr_handlers[] = { +#ifdef CONFIG_CEPH_FS_POSIX_ACL + &posix_acl_access_xattr_handler, + &posix_acl_default_xattr_handler, +#endif +#ifdef CONFIG_CEPH_FS_SECURITY_LABEL + &ceph_security_label_handler, +#endif + &ceph_other_xattr_handler, + NULL, +};