From d47be3dfecaf20255af89a57460285c82d5271ad Mon Sep 17 00:00:00 2001 From: David Quigley Date: Wed, 22 May 2013 12:50:34 -0400 Subject: Security: Add hook to calculate context based on a negative dentry. 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. Acked-by: Eric Paris Acked-by: James Morris 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 Signed-off-by: Steve Dickson Signed-off-by: Trond Myklebust --- security/security.c | 10 ++++++++++ 1 file changed, 10 insertions(+) (limited to 'security/security.c') diff --git a/security/security.c b/security/security.c index a3dce87d1aef..0fe2b2ee9545 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) -- cgit v1.2.3-58-ga151 From 746df9b59c8a5f162c907796c7295d3c4c0d8995 Mon Sep 17 00:00:00 2001 From: David Quigley Date: Wed, 22 May 2013 12:50:35 -0400 Subject: Security: Add Hook to test if the particular xattr is part of a MAC model. The interface to request security labels from user space is the xattr interface. When requesting the security label from an NFS server it is important to make sure the requested xattr actually is a MAC label. This allows us to make sure that we get the desired semantics from the attribute instead of something else such as capabilities or a time based LSM. Acked-by: Eric Paris Acked-by: James Morris 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 Signed-off-by: Trond Myklebust --- include/linux/security.h | 14 ++++++++++++++ security/capability.c | 6 ++++++ security/security.c | 6 ++++++ security/selinux/hooks.c | 6 ++++++ security/smack/smack_lsm.c | 11 +++++++++++ 5 files changed, 43 insertions(+) (limited to 'security/security.c') diff --git a/include/linux/security.h b/include/linux/security.h index c2af46264ae0..cff3e4fc4281 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1323,6 +1323,13 @@ static inline void security_free_mnt_opts(struct security_mnt_opts *opts) * @pages contains the number of pages. * Return 0 if permission is granted. * + * @ismaclabel: + * Check if the extended attribute specified by @name + * represents a MAC label. Returns 1 if name is a MAC + * attribute otherwise returns 0. + * @name full extended attribute name to check against + * LSM as a MAC label. + * * @secid_to_secctx: * Convert secid to security context. If secdata is NULL the length of * the result will be returned in seclen, but no secdata will be returned. @@ -1604,6 +1611,7 @@ struct security_operations { int (*getprocattr) (struct task_struct *p, char *name, char **value); int (*setprocattr) (struct task_struct *p, char *name, void *value, size_t size); + int (*ismaclabel) (const char *name); int (*secid_to_secctx) (u32 secid, char **secdata, u32 *seclen); int (*secctx_to_secid) (const char *secdata, u32 seclen, u32 *secid); void (*release_secctx) (char *secdata, u32 seclen); @@ -1857,6 +1865,7 @@ void security_d_instantiate(struct dentry *dentry, struct inode *inode); int security_getprocattr(struct task_struct *p, char *name, char **value); int security_setprocattr(struct task_struct *p, char *name, void *value, size_t size); int security_netlink_send(struct sock *sk, struct sk_buff *skb); +int security_ismaclabel(const char *name); int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen); int security_secctx_to_secid(const char *secdata, u32 seclen, u32 *secid); void security_release_secctx(char *secdata, u32 seclen); @@ -2547,6 +2556,11 @@ static inline int security_netlink_send(struct sock *sk, struct sk_buff *skb) return cap_netlink_send(sk, skb); } +static inline int security_ismaclabel(const char *name) +{ + return 0; +} + static inline int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { return -EOPNOTSUPP; diff --git a/security/capability.c b/security/capability.c index 58578b4bdad4..71f9682bfb54 100644 --- a/security/capability.c +++ b/security/capability.c @@ -823,6 +823,11 @@ static int cap_setprocattr(struct task_struct *p, char *name, void *value, return -EINVAL; } +static int cap_ismaclabel(const char *name) +{ + return 0; +} + static int cap_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { return -EOPNOTSUPP; @@ -1042,6 +1047,7 @@ void __init security_fixup_ops(struct security_operations *ops) set_to_cap_if_null(ops, d_instantiate); set_to_cap_if_null(ops, getprocattr); set_to_cap_if_null(ops, setprocattr); + set_to_cap_if_null(ops, ismaclabel); set_to_cap_if_null(ops, secid_to_secctx); set_to_cap_if_null(ops, secctx_to_secid); set_to_cap_if_null(ops, release_secctx); diff --git a/security/security.c b/security/security.c index 0fe2b2ee9545..c3ceb754e705 100644 --- a/security/security.c +++ b/security/security.c @@ -1057,6 +1057,12 @@ int security_netlink_send(struct sock *sk, struct sk_buff *skb) return security_ops->netlink_send(sk, skb); } +int security_ismaclabel(const char *name) +{ + return security_ops->ismaclabel(name); +} +EXPORT_SYMBOL(security_ismaclabel); + int security_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { return security_ops->secid_to_secctx(secid, secdata, seclen); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index b1f7bd727bd9..bbf219a494d0 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -5454,6 +5454,11 @@ abort_change: return error; } +static int selinux_ismaclabel(const char *name) +{ + return (strcmp(name, XATTR_SELINUX_SUFFIX) == 0); +} + static int selinux_secid_to_secctx(u32 secid, char **secdata, u32 *seclen) { return security_sid_to_context(secid, secdata, seclen); @@ -5692,6 +5697,7 @@ static struct security_operations selinux_ops = { .getprocattr = selinux_getprocattr, .setprocattr = selinux_setprocattr, + .ismaclabel = selinux_ismaclabel, .secid_to_secctx = selinux_secid_to_secctx, .secctx_to_secid = selinux_secctx_to_secid, .release_secctx = selinux_release_secctx, diff --git a/security/smack/smack_lsm.c b/security/smack/smack_lsm.c index d52c780bdb78..a7f485bb4e2e 100644 --- a/security/smack/smack_lsm.c +++ b/security/smack/smack_lsm.c @@ -3328,6 +3328,16 @@ static void smack_audit_rule_free(void *vrule) #endif /* CONFIG_AUDIT */ +/** + * smack_ismaclabel - check if xattr @name references a smack MAC label + * @name: Full xattr name to check. + */ +static int smack_ismaclabel(const char *name) +{ + return (strcmp(name, XATTR_SMACK_SUFFIX) == 0); +} + + /** * smack_secid_to_secctx - return the smack label for a secid * @secid: incoming integer @@ -3524,6 +3534,7 @@ struct security_operations smack_ops = { .audit_rule_free = smack_audit_rule_free, #endif /* CONFIG_AUDIT */ + .ismaclabel = smack_ismaclabel, .secid_to_secctx = smack_secid_to_secctx, .secctx_to_secid = smack_secctx_to_secid, .release_secctx = smack_release_secctx, -- cgit v1.2.3-58-ga151 From 649f6e7718891fe7691e5084ce3fa623acba3129 Mon Sep 17 00:00:00 2001 From: David Quigley Date: Wed, 22 May 2013 12:50:36 -0400 Subject: LSM: Add flags field to security_sb_set_mnt_opts for in kernel mount data. There is no way to differentiate if a text mount option is passed from user space or the kernel. A flags field is being added to the security_sb_set_mnt_opts hook to allow for in kernel security flags to be sent to the LSM for processing in addition to the text options received from mount. This patch also updated existing code to fix compilation errors. Acked-by: Eric Paris Acked-by: James Morris Signed-off-by: David P. Quigley Signed-off-by: Miguel Rodel Felipe Signed-off-by: Phua Eu Gene Signed-off-by: Khin Mi Mi Aung Signed-off-by: Trond Myklebust --- fs/nfs/super.c | 3 ++- include/linux/security.h | 13 ++++++++++--- security/capability.c | 5 ++++- security/security.c | 7 +++++-- security/selinux/hooks.c | 12 ++++++++++-- 5 files changed, 31 insertions(+), 9 deletions(-) (limited to 'security/security.c') diff --git a/fs/nfs/super.c b/fs/nfs/super.c index a366107a7331..c1bbb53d444a 100644 --- a/fs/nfs/super.c +++ b/fs/nfs/super.c @@ -2411,7 +2411,8 @@ static int nfs_bdi_register(struct nfs_server *server) int nfs_set_sb_security(struct super_block *s, struct dentry *mntroot, struct nfs_mount_info *mount_info) { - return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts); + return security_sb_set_mnt_opts(s, &mount_info->parsed->lsm_opts, + 0, NULL); } EXPORT_SYMBOL_GPL(nfs_set_sb_security); diff --git a/include/linux/security.h b/include/linux/security.h index cff3e4fc4281..aa656fbc4308 100644 --- a/include/linux/security.h +++ b/include/linux/security.h @@ -1456,7 +1456,9 @@ struct security_operations { int (*sb_pivotroot) (struct path *old_path, struct path *new_path); int (*sb_set_mnt_opts) (struct super_block *sb, - struct security_mnt_opts *opts); + struct security_mnt_opts *opts, + unsigned long kern_flags, + unsigned long *set_kern_flags); int (*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); @@ -1747,7 +1749,10 @@ int security_sb_mount(const char *dev_name, struct path *path, const char *type, unsigned long flags, void *data); int security_sb_umount(struct vfsmount *mnt, int flags); int security_sb_pivotroot(struct path *old_path, struct path *new_path); -int security_sb_set_mnt_opts(struct super_block *sb, struct security_mnt_opts *opts); +int security_sb_set_mnt_opts(struct super_block *sb, + struct security_mnt_opts *opts, + unsigned long kern_flags, + unsigned long *set_kern_flags); int 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); @@ -2037,7 +2042,9 @@ static inline int security_sb_pivotroot(struct path *old_path, } static inline int security_sb_set_mnt_opts(struct super_block *sb, - struct security_mnt_opts *opts) + struct security_mnt_opts *opts, + unsigned long kern_flags, + unsigned long *set_kern_flags) { return 0; } diff --git a/security/capability.c b/security/capability.c index 71f9682bfb54..d32e16e3c6ae 100644 --- a/security/capability.c +++ b/security/capability.c @@ -91,7 +91,10 @@ static int cap_sb_pivotroot(struct path *old_path, struct path *new_path) } static int cap_sb_set_mnt_opts(struct super_block *sb, - struct security_mnt_opts *opts) + struct security_mnt_opts *opts, + unsigned long kern_flags, + unsigned long *set_kern_flags) + { if (unlikely(opts->num_mnt_opts)) return -EOPNOTSUPP; diff --git a/security/security.c b/security/security.c index c3ceb754e705..8d0b9a79611a 100644 --- a/security/security.c +++ b/security/security.c @@ -294,9 +294,12 @@ int security_sb_pivotroot(struct path *old_path, struct path *new_path) } int security_sb_set_mnt_opts(struct super_block *sb, - struct security_mnt_opts *opts) + struct security_mnt_opts *opts, + unsigned long kern_flags, + unsigned long *set_kern_flags) { - return security_ops->sb_set_mnt_opts(sb, opts); + return security_ops->sb_set_mnt_opts(sb, opts, kern_flags, + set_kern_flags); } EXPORT_SYMBOL(security_sb_set_mnt_opts); diff --git a/security/selinux/hooks.c b/security/selinux/hooks.c index bbf219a494d0..f3b54466a037 100644 --- a/security/selinux/hooks.c +++ b/security/selinux/hooks.c @@ -552,7 +552,9 @@ static int bad_option(struct superblock_security_struct *sbsec, char flag, * labeling information. */ static int selinux_set_mnt_opts(struct super_block *sb, - struct security_mnt_opts *opts) + struct security_mnt_opts *opts, + unsigned long kern_flags, + unsigned long *set_kern_flags) { const struct cred *cred = current_cred(); int rc = 0, i; @@ -580,6 +582,12 @@ static int selinux_set_mnt_opts(struct super_block *sb, "before the security server is initialized\n"); goto out; } + if (kern_flags && !set_kern_flags) { + /* Specifying internal flags without providing a place to + * place the results is not allowed */ + rc = -EINVAL; + goto out; + } /* * Binary mount data FS will come through this function twice. Once @@ -980,7 +988,7 @@ static int superblock_doinit(struct super_block *sb, void *data) goto out_err; out: - rc = selinux_set_mnt_opts(sb, &opts); + rc = selinux_set_mnt_opts(sb, &opts, 0, NULL); out_err: security_free_mnt_opts(&opts); -- cgit v1.2.3-58-ga151 From c9bccef6b98ae563f725f6e315d8adc685239781 Mon Sep 17 00:00:00 2001 From: David Quigley Date: Wed, 22 May 2013 12:50:45 -0400 Subject: NFS: Extend NFS xattr handlers to accept the security namespace The existing NFSv4 xattr handlers do not accept xattr calls to the security namespace. This patch extends these handlers to accept xattrs from the security namespace in addition to the default NFSv4 ACL namespace. Acked-by: James Morris 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 Signed-off-by: Trond Myklebust --- fs/nfs/nfs4proc.c | 50 ++++++++++++++++++++++++++++++++++++++++++++++++++ security/security.c | 1 + 2 files changed, 51 insertions(+) (limited to 'security/security.c') diff --git a/fs/nfs/nfs4proc.c b/fs/nfs/nfs4proc.c index 1dc7aec8e946..dfef23f1a66a 100644 --- a/fs/nfs/nfs4proc.c +++ b/fs/nfs/nfs4proc.c @@ -5640,6 +5640,53 @@ static size_t nfs4_xattr_list_nfs4_acl(struct dentry *dentry, char *list, return len; } +#ifdef CONFIG_NFS_V4_SECURITY_LABEL +static inline int nfs4_server_supports_labels(struct nfs_server *server) +{ + return server->caps & NFS_CAP_SECURITY_LABEL; +} + +static int nfs4_xattr_set_nfs4_label(struct dentry *dentry, const char *key, + const void *buf, size_t buflen, + int flags, int type) +{ + if (security_ismaclabel(key)) + return nfs4_set_security_label(dentry, buf, buflen); + + return -EOPNOTSUPP; +} + +static int nfs4_xattr_get_nfs4_label(struct dentry *dentry, const char *key, + void *buf, size_t buflen, int type) +{ + if (security_ismaclabel(key)) + return nfs4_get_security_label(dentry->d_inode, buf, buflen); + return -EOPNOTSUPP; +} + +static size_t nfs4_xattr_list_nfs4_label(struct dentry *dentry, char *list, + size_t list_len, const char *name, + size_t name_len, int type) +{ + size_t len = 0; + + if (nfs_server_capable(dentry->d_inode, NFS_CAP_SECURITY_LABEL)) { + len = security_inode_listsecurity(dentry->d_inode, NULL, 0); + if (list && len <= list_len) + security_inode_listsecurity(dentry->d_inode, list, len); + } + return len; +} + +static const struct xattr_handler nfs4_xattr_nfs4_label_handler = { + .prefix = XATTR_SECURITY_PREFIX, + .list = nfs4_xattr_list_nfs4_label, + .get = nfs4_xattr_get_nfs4_label, + .set = nfs4_xattr_set_nfs4_label, +}; +#endif + + /* * nfs_fhget will use either the mounted_on_fileid or the fileid */ @@ -7468,6 +7515,9 @@ static const struct xattr_handler nfs4_xattr_nfs4_acl_handler = { const struct xattr_handler *nfs4_xattr_handlers[] = { &nfs4_xattr_nfs4_acl_handler, +#ifdef CONFIG_NFS_V4_SECURITY_LABEL + &nfs4_xattr_nfs4_label_handler, +#endif NULL }; diff --git a/security/security.c b/security/security.c index 8d0b9a79611a..94b35aef6871 100644 --- a/security/security.c +++ b/security/security.c @@ -660,6 +660,7 @@ int security_inode_listsecurity(struct inode *inode, char *buffer, size_t buffer return 0; return security_ops->inode_listsecurity(inode, buffer, buffer_size); } +EXPORT_SYMBOL(security_inode_listsecurity); void security_inode_getsecid(const struct inode *inode, u32 *secid) { -- cgit v1.2.3-58-ga151