Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1757553Ab1D1Nd3 (ORCPT ); Thu, 28 Apr 2011 09:33:29 -0400 Received: from e37.co.us.ibm.com ([32.97.110.158]:47360 "EHLO e37.co.us.ibm.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1751799Ab1D1NdZ (ORCPT ); Thu, 28 Apr 2011 09:33:25 -0400 Subject: Re: [RFC][PATCH 7/7] ima: added new LSM conditions in the policy From: Mimi Zohar To: Roberto Sassu Cc: linux-security-module@vger.kernel.org, linux-fsdevel@vger.kernel.org, linux-kernel@vger.kernel.org, dhowells@redhat.com, jmorris@namei.org, safford@watson.ibm.com, tyhicks@linux.vnet.ibm.com, kirkland@canonical.com, ecryptfs-devel@lists.launchpad.net, casey@schaufler-ca.com, eparis@redhat.com, sds@tycho.nsa.gov, selinux@tycho.nsa.gov, viro@zeniv.linux.org.uk In-Reply-To: <1303907657-18366-8-git-send-email-roberto.sassu@polito.it> References: <1303907657-18366-1-git-send-email-roberto.sassu@polito.it> <1303907657-18366-8-git-send-email-roberto.sassu@polito.it> Content-Type: text/plain; charset="UTF-8" Date: Thu, 28 Apr 2011 09:32:38 -0400 Message-ID: <1303997558.3139.16.camel@localhost.localdomain> Mime-Version: 1.0 X-Mailer: Evolution 2.30.3 (2.30.3-1.fc13) Content-Transfer-Encoding: 7bit Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org Content-Length: 8520 Lines: 232 On Wed, 2011-04-27 at 14:34 +0200, Roberto Sassu wrote: > The new parameters 'fowner_user', 'fowner_role' and 'fowner_type' are new > LSM conditions that allow to measure inodes whose opened file descriptor > has the label given as a value. > > Signed-off-by: Roberto Sassu Nice. I really like the 'fowner_' prefix. If you don't object, I'll change the ima-appraisal keyword from 'owner' to 'fowner' as well. Acked-by: Mimi Zohar thanks, Mimi > --- > Documentation/ABI/testing/ima_policy | 7 ++++- > security/integrity/ima/ima.h | 4 +- > security/integrity/ima/ima_api.c | 4 +- > security/integrity/ima/ima_main.c | 4 +- > security/integrity/ima/ima_policy.c | 45 +++++++++++++++++++++++++++++---- > 5 files changed, 51 insertions(+), 13 deletions(-) > > diff --git a/Documentation/ABI/testing/ima_policy b/Documentation/ABI/testing/ima_policy > index 6cd6dae..ee49345 100644 > --- a/Documentation/ABI/testing/ima_policy > +++ b/Documentation/ABI/testing/ima_policy > @@ -18,7 +18,8 @@ Description: > condition:= base | lsm > base: [[func=] [mask=] [fsmagic=] [uid=]] > lsm: [[subj_user=] [subj_role=] [subj_type=] > - [obj_user=] [obj_role=] [obj_type=]] > + [obj_user=] [obj_role=] [obj_type=] > + [fowner_user=] [fowner_role=] [fowner_type=]] > > base: func:= [BPRM_CHECK][FILE_MMAP][FILE_CHECK] > mask:= [MAY_READ] [MAY_WRITE] [MAY_APPEND] [MAY_EXEC] > @@ -46,6 +47,10 @@ Description: > all files mmapped executable in file_mmap, and all files > open for read by root in do_filp_open. > > + LSM conditions starting with obj_ refer to security attributes > + of inodes while those starting with fowner_ involve file > + descriptors. > + > Examples of LSM specific definitions: > > SELinux: > diff --git a/security/integrity/ima/ima.h b/security/integrity/ima/ima.h > index 08408bd..3a05625 100644 > --- a/security/integrity/ima/ima.h > +++ b/security/integrity/ima/ima.h > @@ -110,7 +110,7 @@ struct ima_iint_cache { > }; > > /* LIM API function definitions */ > -int ima_must_measure(struct inode *inode, int mask, int function); > +int ima_must_measure(struct file *file, int mask, int function); > int ima_collect_measurement(struct ima_iint_cache *iint, struct file *file); > void ima_store_measurement(struct ima_iint_cache *iint, struct file *file, > const unsigned char *filename); > @@ -128,7 +128,7 @@ struct ima_iint_cache *ima_iint_find(struct inode *inode); > /* IMA policy related functions */ > enum ima_hooks { FILE_CHECK = 1, FILE_MMAP, BPRM_CHECK }; > > -int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask); > +int ima_match_policy(struct file *file, enum ima_hooks func, int mask); > void ima_init_policy(void); > void ima_update_policy(void); > ssize_t ima_parse_add_rule(char *); > diff --git a/security/integrity/ima/ima_api.c b/security/integrity/ima/ima_api.c > index da36d2c..d815392 100644 > --- a/security/integrity/ima/ima_api.c > +++ b/security/integrity/ima/ima_api.c > @@ -108,11 +108,11 @@ err_out: > * Return 0 to measure. For matching a DONT_MEASURE policy, no policy, > * or other error, return an error code. > */ > -int ima_must_measure(struct inode *inode, int mask, int function) > +int ima_must_measure(struct file *file, int mask, int function) > { > int must_measure; > > - must_measure = ima_match_policy(inode, function, mask); > + must_measure = ima_match_policy(file, function, mask); > return must_measure ? 0 : -EACCES; > } > > diff --git a/security/integrity/ima/ima_main.c b/security/integrity/ima/ima_main.c > index 39d66dc..9eaca61 100644 > --- a/security/integrity/ima/ima_main.c > +++ b/security/integrity/ima/ima_main.c > @@ -65,7 +65,7 @@ static void ima_rdwr_violation_check(struct file *file) > goto out; > } > > - rc = ima_must_measure(inode, MAY_READ, FILE_CHECK); > + rc = ima_must_measure(file, MAY_READ, FILE_CHECK); > if (rc < 0) > goto out; > > @@ -127,7 +127,7 @@ static int process_measurement(struct file *file, const unsigned char *filename, > if (!ima_initialized || !S_ISREG(inode->i_mode)) > return 0; > > - rc = ima_must_measure(inode, mask, function); > + rc = ima_must_measure(file, mask, function); > if (rc != 0) > return rc; > retry: > diff --git a/security/integrity/ima/ima_policy.c b/security/integrity/ima/ima_policy.c > index d661afb..115c2e7 100644 > --- a/security/integrity/ima/ima_policy.c > +++ b/security/integrity/ima/ima_policy.c > @@ -27,9 +27,10 @@ > > enum ima_action { UNKNOWN = -1, DONT_MEASURE = 0, MEASURE }; > > -#define MAX_LSM_RULES 6 > +#define MAX_LSM_RULES 9 > enum lsm_rule_types { LSM_OBJ_USER, LSM_OBJ_ROLE, LSM_OBJ_TYPE, > - LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE > + LSM_SUBJ_USER, LSM_SUBJ_ROLE, LSM_SUBJ_TYPE, > + LSM_FOWNER_USER, LSM_FOWNER_ROLE, LSM_FOWNER_TYPE > }; > > struct ima_measure_rule_entry { > @@ -96,9 +97,10 @@ __setup("ima_tcb", default_policy_setup); > * Returns true on rule match, false on failure. > */ > static bool ima_match_rules(struct ima_measure_rule_entry *rule, > - struct inode *inode, enum ima_hooks func, int mask) > + struct file *file, enum ima_hooks func, int mask) > { > struct task_struct *tsk = current; > + struct inode *inode = file->f_dentry->d_inode; > int i; > > if ((rule->flags & IMA_FUNC) && rule->func != func) > @@ -112,7 +114,7 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, > return false; > for (i = 0; i < MAX_LSM_RULES; i++) { > int rc = 0; > - u32 osid, sid; > + u32 osid, sid, fsid; > > if (!rule->lsm[i].rule) > continue; > @@ -137,6 +139,15 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, > Audit_equal, > rule->lsm[i].rule, > NULL); > + case LSM_FOWNER_USER: > + case LSM_FOWNER_ROLE: > + case LSM_FOWNER_TYPE: > + security_file_getsecid(file, &fsid); > + rc = security_filter_rule_match(fsid, > + rule->lsm[i].type, > + Audit_equal, > + rule->lsm[i].rule, > + NULL); > default: > break; > } > @@ -159,14 +170,14 @@ static bool ima_match_rules(struct ima_measure_rule_entry *rule, > * as elements in the list are never deleted, nor does the list > * change.) > */ > -int ima_match_policy(struct inode *inode, enum ima_hooks func, int mask) > +int ima_match_policy(struct file *file, enum ima_hooks func, int mask) > { > struct ima_measure_rule_entry *entry; > > list_for_each_entry(entry, ima_measure, list) { > bool rc; > > - rc = ima_match_rules(entry, inode, func, mask); > + rc = ima_match_rules(entry, file, func, mask); > if (rc) > return entry->action; > } > @@ -222,6 +233,7 @@ enum { > Opt_measure = 1, Opt_dont_measure, > Opt_obj_user, Opt_obj_role, Opt_obj_type, > Opt_subj_user, Opt_subj_role, Opt_subj_type, > + Opt_fowner_user, Opt_fowner_role, Opt_fowner_type, > Opt_func, Opt_mask, Opt_fsmagic, Opt_uid > }; > > @@ -234,6 +246,9 @@ static match_table_t policy_tokens = { > {Opt_subj_user, "subj_user=%s"}, > {Opt_subj_role, "subj_role=%s"}, > {Opt_subj_type, "subj_type=%s"}, > + {Opt_fowner_user, "fowner_user=%s"}, > + {Opt_fowner_role, "fowner_role=%s"}, > + {Opt_fowner_type, "fowner_type=%s"}, > {Opt_func, "func=%s"}, > {Opt_mask, "mask=%s"}, > {Opt_fsmagic, "fsmagic=%s"}, > @@ -407,6 +422,24 @@ static int ima_parse_rule(char *rule, struct ima_measure_rule_entry *entry) > LSM_SUBJ_TYPE, > AUDIT_SUBJ_TYPE); > break; > + case Opt_fowner_user: > + ima_log_string(ab, "fowner_user", args[0].from); > + result = ima_lsm_rule_init(entry, args[0].from, > + LSM_FOWNER_USER, > + AUDIT_SUBJ_USER); > + break; > + case Opt_fowner_role: > + ima_log_string(ab, "fowner_role", args[0].from); > + result = ima_lsm_rule_init(entry, args[0].from, > + LSM_FOWNER_ROLE, > + AUDIT_SUBJ_ROLE); > + break; > + case Opt_fowner_type: > + ima_log_string(ab, "fowner_type", args[0].from); > + result = ima_lsm_rule_init(entry, args[0].from, > + LSM_FOWNER_TYPE, > + AUDIT_SUBJ_TYPE); > + break; > case Opt_err: > ima_log_string(ab, "UNKNOWN", p); > result = -EINVAL; -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/