From patchwork Mon Jan 7 14:47:22 2013 Content-Type: text/plain; charset="utf-8" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit X-Patchwork-Submitter: Steve Dickson X-Patchwork-Id: 1941231 Return-Path: X-Original-To: patchwork-linux-nfs@patchwork.kernel.org Delivered-To: patchwork-process-083081@patchwork2.kernel.org Received: from vger.kernel.org (vger.kernel.org [209.132.180.67]) by patchwork2.kernel.org (Postfix) with ESMTP id 0EE35DF230 for ; Mon, 7 Jan 2013 14:53:20 +0000 (UTC) Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1751536Ab3AGOxS (ORCPT ); Mon, 7 Jan 2013 09:53:18 -0500 Received: from 183.141.211.66.inaddr.G4.NET ([66.211.141.183]:52657 "EHLO Dobby.4dicksons.org" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751597Ab3AGOxR (ORCPT ); Mon, 7 Jan 2013 09:53:17 -0500 Received: from tophat.home.4dicksons.org ([192.168.62.20]) by Dobby.4dicksons.org with esmtp (Exim 4.63) (envelope-from ) id 1TsE4d-0001UV-7R; Mon, 07 Jan 2013 09:53:12 -0500 From: Steve Dickson To: David Quigley , Trond Myklebust , "J. Bruce Fields" Cc: Linux NFS Mailing list Subject: [PATCH 01/12] Security: Add hook to calculate context based on a negative dentry. Date: Mon, 7 Jan 2013 09:47:22 -0500 Message-Id: <1357570053-28849-2-git-send-email-steved@redhat.com> X-Mailer: git-send-email 1.7.11.7 In-Reply-To: <1357570053-28849-1-git-send-email-steved@redhat.com> References: <1357570053-28849-1-git-send-email-steved@redhat.com> X-Spam-Score: -2.9 (--) Sender: linux-nfs-owner@vger.kernel.org Precedence: bulk List-ID: X-Mailing-List: linux-nfs@vger.kernel.org From: David Quigley There is a time where we need to calculate a context without the inode having been created yet. To do this we take the negative dentry and calculate a context based on the process and the parent directory contexts. Signed-off-by: Matthew N. Dodd Signed-off-by: Miguel Rodel Felipe Signed-off-by: Phua Eu Gene Signed-off-by: Khin Mi Mi Aung --- include/linux/security.h | 27 +++++++++++++++++++++++++++ security/capability.c | 8 ++++++++ security/security.c | 10 ++++++++++ security/selinux/hooks.c | 35 +++++++++++++++++++++++++++++++++++ 4 files changed, 80 insertions(+) diff --git a/include/linux/security.h b/include/linux/security.h index 0f6afc6..27af0cb 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -26,6 +26,7 @@ #include #include #include +#include struct linux_binprm; struct cred; @@ -306,6 +307,15 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * Parse a string of security data filling in the opts structure * @options string containing all mount options known by the LSM * @opts binary data structure usable by the LSM + * @dentry_init_security: + * Compute a context for a dentry as the inode is not yet available + * since NFSv4 has no label backed by an EA anyway. + * @dentry dentry to use in calculating the context. + * @mode mode used to determine resource type. + * @name name of the last path component used to create file + * @ctx pointer to place the pointer to the resulting context in. + * @ctxlen point to place the length of the resulting context. + * * * Security hooks for inode operations. * @@ -1427,6 +1437,10 @@ struct security_operations { void (*sb_clone_mnt_opts) (const struct super_block *oldsb, struct super_block *newsb); int (*sb_parse_opts_str) (char *options, struct security_mnt_opts *opts); + int (*dentry_init_security) (struct dentry *dentry, int mode, + struct qstr *name, void **ctx, + u32 *ctxlen); + #ifdef CONFIG_SECURITY_PATH int (*path_unlink) (struct path *dir, struct dentry *dentry); @@ -1709,6 +1723,9 @@ int security_sb_set_mnt_opts(struct super_block *sb, struct security_mnt_opts *o void security_sb_clone_mnt_opts(const struct super_block *oldsb, struct super_block *newsb); int security_sb_parse_opts_str(char *options, struct security_mnt_opts *opts); +int security_dentry_init_security(struct dentry *dentry, int mode, + struct qstr *name, void **ctx, + u32 *ctxlen); int security_inode_alloc(struct inode *inode); void security_inode_free(struct inode *inode); @@ -2013,6 +2030,16 @@ static inline int security_inode_alloc(struct inode *inode) static inline void security_inode_free(struct inode *inode) { } +static inline int security_dentry_init_security(struct dentry *dentry, + int mode, + struct qstr *name, + void **ctx, + u32 *ctxlen) +{ + return -EOPNOTSUPP; +} + + static inline int security_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, diff --git a/security/capability.c b/security/capability.c index 0fe5a02..6647bc0 100644 --- a/security/capability.c +++ b/security/capability.c @@ -108,6 +108,13 @@ static int cap_sb_parse_opts_str(char *options, struct security_mnt_opts *opts) return 0; } +static int cap_dentry_init_security(struct dentry *dentry, int mode, + struct qstr *name, void **ctx, + u32 *ctxlen) +{ + return 0; +} + static int cap_inode_alloc_security(struct inode *inode) { return 0; @@ -910,6 +917,7 @@ void __init security_fixup_ops(struct security_operations *ops) set_to_cap_if_null(ops, sb_set_mnt_opts); set_to_cap_if_null(ops, sb_clone_mnt_opts); set_to_cap_if_null(ops, sb_parse_opts_str); + set_to_cap_if_null(ops, dentry_init_security); set_to_cap_if_null(ops, inode_alloc_security); set_to_cap_if_null(ops, inode_free_security); set_to_cap_if_null(ops, inode_init_security); diff --git a/security/security.c b/security/security.c index daa97f4..4a263db 100644 --- a/security/security.c +++ b/security/security.c @@ -12,6 +12,7 @@ */ #include +#include #include #include #include @@ -324,6 +325,15 @@ void security_inode_free(struct inode *inode) security_ops->inode_free_security(inode); } +int security_dentry_init_security(struct dentry *dentry, int mode, + struct qstr *name, void **ctx, + u32 *ctxlen) +{ + return security_ops->dentry_init_security(dentry, mode, name, + ctx, ctxlen); +} +EXPORT_SYMBOL(security_dentry_init_security); + int security_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, const initxattrs initxattrs, void *fs_data) diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index 61a5336..22d9adf 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -2483,6 +2483,40 @@ static void selinux_inode_free_security(struct inode *inode) inode_free_security(inode); } +static int selinux_dentry_init_security(struct dentry *dentry, int mode, + struct qstr *name, void **ctx, + u32 *ctxlen) +{ + struct cred *cred = current_cred(); + struct task_security_struct *tsec; + struct inode_security_struct *dsec; + struct superblock_security_struct *sbsec; + struct inode *dir = dentry->d_parent->d_inode; + u32 newsid; + int rc; + + tsec = cred->security; + dsec = dir->i_security; + sbsec = dir->i_sb->s_security; + + if (tsec->create_sid && sbsec->behavior != SECURITY_FS_USE_MNTPOINT) { + newsid = tsec->create_sid; + } else { + rc = security_transition_sid(tsec->sid, dsec->sid, + inode_mode_to_security_class(mode), + name, + &newsid); + if (rc) { + printk(KERN_WARNING + "%s: security_transition_sid failed, rc=%d\n", + __func__, -rc); + return rc; + } + } + + return security_sid_to_context(newsid, (char **)ctx, ctxlen); +} + static int selinux_inode_init_security(struct inode *inode, struct inode *dir, const struct qstr *qstr, char **name, void **value, size_t *len) @@ -5509,6 +5543,7 @@ static struct security_operations selinux_ops = { .sb_clone_mnt_opts = selinux_sb_clone_mnt_opts, .sb_parse_opts_str = selinux_parse_opts_str, + .dentry_init_security = selinux_dentry_init_security, .inode_alloc_security = selinux_inode_alloc_security, .inode_free_security = selinux_inode_free_security,