diff options
| -rw-r--r-- | include/linux/audit.h | 5 | ||||
| -rw-r--r-- | include/linux/selinux.h | 112 | ||||
| -rw-r--r-- | security/selinux/Makefile | 2 | ||||
| -rw-r--r-- | security/selinux/avc.c | 13 | ||||
| -rw-r--r-- | security/selinux/exports.c | 28 | ||||
| -rw-r--r-- | security/selinux/ss/mls.c | 30 | ||||
| -rw-r--r-- | security/selinux/ss/mls.h | 4 | ||||
| -rw-r--r-- | security/selinux/ss/services.c | 235 |
8 files changed, 419 insertions, 10 deletions
diff --git a/include/linux/audit.h b/include/linux/audit.h index 39fef6ebb85..740f950397b 100644 --- a/include/linux/audit.h +++ b/include/linux/audit.h @@ -145,6 +145,11 @@ #define AUDIT_PERS 10 #define AUDIT_ARCH 11 #define AUDIT_MSGTYPE 12 +#define AUDIT_SE_USER 13 /* security label user */ +#define AUDIT_SE_ROLE 14 /* security label role */ +#define AUDIT_SE_TYPE 15 /* security label type */ +#define AUDIT_SE_SEN 16 /* security label sensitivity label */ +#define AUDIT_SE_CLR 17 /* security label clearance label */ /* These are ONLY useful when checking * at syscall exit time (AUDIT_AT_EXIT). */ diff --git a/include/linux/selinux.h b/include/linux/selinux.h new file mode 100644 index 00000000000..9d684b1728b --- /dev/null +++ b/include/linux/selinux.h @@ -0,0 +1,112 @@ +/* + * SELinux services exported to the rest of the kernel. + * + * Author: James Morris <jmorris@redhat.com> + * + * Copyright (C) 2005 Red Hat, Inc., James Morris <jmorris@redhat.com> + * Copyright (C) 2006 Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2, + * as published by the Free Software Foundation. + */ +#ifndef _LINUX_SELINUX_H +#define _LINUX_SELINUX_H + +struct selinux_audit_rule; +struct audit_context; + +#ifdef CONFIG_SECURITY_SELINUX + +/** + * selinux_audit_rule_init - alloc/init an selinux audit rule structure. + * @field: the field this rule refers to + * @op: the operater the rule uses + * @rulestr: the text "target" of the rule + * @rule: pointer to the new rule structure returned via this + * + * Returns 0 if successful, -errno if not. On success, the rule structure + * will be allocated internally. The caller must free this structure with + * selinux_audit_rule_free() after use. + */ +int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, + struct selinux_audit_rule **rule); + +/** + * selinux_audit_rule_free - free an selinux audit rule structure. + * @rule: pointer to the audit rule to be freed + * + * This will free all memory associated with the given rule. + * If @rule is NULL, no operation is performed. + */ +void selinux_audit_rule_free(struct selinux_audit_rule *rule); + +/** + * selinux_audit_rule_match - determine if a context ID matches a rule. + * @ctxid: the context ID to check + * @field: the field this rule refers to + * @op: the operater the rule uses + * @rule: pointer to the audit rule to check against + * @actx: the audit context (can be NULL) associated with the check + * + * Returns 1 if the context id matches the rule, 0 if it does not, and + * -errno on failure. + */ +int selinux_audit_rule_match(u32 ctxid, u32 field, u32 op, + struct selinux_audit_rule *rule, + struct audit_context *actx); + +/** + * selinux_audit_set_callback - set the callback for policy reloads. + * @callback: the function to call when the policy is reloaded + * + * This sets the function callback function that will update the rules + * upon policy reloads. This callback should rebuild all existing rules + * using selinux_audit_rule_init(). + */ +void selinux_audit_set_callback(int (*callback)(void)); + +/** + * selinux_task_ctxid - determine a context ID for a process. + * @tsk: the task object + * @ctxid: ID value returned via this + * + * On return, ctxid will contain an ID for the context. This value + * should only be used opaquely. + */ +void selinux_task_ctxid(struct task_struct *tsk, u32 *ctxid); + +#else + +static inline int selinux_audit_rule_init(u32 field, u32 op, + char *rulestr, + struct selinux_audit_rule **rule) +{ + return -ENOTSUPP; +} + +static inline void selinux_audit_rule_free(struct selinux_audit_rule *rule) +{ + return; +} + +static inline int selinux_audit_rule_match(u32 ctxid, u32 field, u32 op, + struct selinux_audit_rule *rule, + struct audit_context *actx) +{ + return 0; +} + +static inline void selinux_audit_set_callback(int (*callback)(void)) +{ + return; +} + +static inline void selinux_task_ctxid(struct task_struct *tsk, u32 *ctxid) +{ + *ctxid = 0; +} + +#endif /* CONFIG_SECURITY_SELINUX */ + +#endif /* _LINUX_SELINUX_H */ diff --git a/security/selinux/Makefile b/security/selinux/Makefile index 688c0a267b6..faf2e02e441 100644 --- a/security/selinux/Makefile +++ b/security/selinux/Makefile @@ -4,7 +4,7 @@ obj-$(CONFIG_SECURITY_SELINUX) := selinux.o ss/ -selinux-y := avc.o hooks.o selinuxfs.o netlink.o nlmsgtab.o netif.o +selinux-y := avc.o hooks.o selinuxfs.o netlink.o nlmsgtab.o netif.o exports.o selinux-$(CONFIG_SECURITY_NETWORK_XFRM) += xfrm.o diff --git a/security/selinux/avc.c b/security/selinux/avc.c index ac5d69bb337..a300702da52 100644 --- a/security/selinux/avc.c +++ b/security/selinux/avc.c @@ -800,7 +800,7 @@ out: int avc_ss_reset(u32 seqno) { struct avc_callback_node *c; - int i, rc = 0; + int i, rc = 0, tmprc; unsigned long flag; struct avc_node *node; @@ -813,15 +813,16 @@ int avc_ss_reset(u32 seqno) for (c = avc_callbacks; c; c = c->next) { if (c->events & AVC_CALLBACK_RESET) { - rc = c->callback(AVC_CALLBACK_RESET, - 0, 0, 0, 0, NULL); - if (rc) - goto out; + tmprc = c->callback(AVC_CALLBACK_RESET, + 0, 0, 0, 0, NULL); + /* save the first error encountered for the return + value and continue processing the callbacks */ + if (!rc) + rc = tmprc; } } avc_latest_notif_update(seqno, 0); -out: return rc; } diff --git a/security/selinux/exports.c b/security/selinux/exports.c new file mode 100644 index 00000000000..333c4c7824d --- /dev/null +++ b/security/selinux/exports.c @@ -0,0 +1,28 @@ +/* + * SELinux services exported to the rest of the kernel. + * + * Author: James Morris <jmorris@redhat.com> + * + * Copyright (C) 2005 Red Hat, Inc., James Morris <jmorris@redhat.com> + * Copyright (C) 2006 Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License version 2, + * as published by the Free Software Foundation. + */ +#include <linux/types.h> +#include <linux/kernel.h> +#include <linux/module.h> +#include <linux/selinux.h> + +#include "security.h" +#include "objsec.h" + +void selinux_task_ctxid(struct task_struct *tsk, u32 *ctxid) +{ + struct task_security_struct *tsec = tsk->security; + if (selinux_enabled) + *ctxid = tsec->sid; + else + *ctxid = 0; +} diff --git a/security/selinux/ss/mls.c b/security/selinux/ss/mls.c index 84047f69f9c..7bc5b6440f7 100644 --- a/security/selinux/ss/mls.c +++ b/security/selinux/ss/mls.c @@ -8,7 +8,7 @@ * * Support for enhanced MLS infrastructure. * - * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. + * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. */ #include <linux/kernel.h> @@ -385,6 +385,34 @@ out: } /* + * Set the MLS fields in the security context structure + * `context' based on the string representation in + * the string `str'. This function will allocate temporary memory with the + * given constraints of gfp_mask. + */ +int mls_from_string(char *str, struct context *context, gfp_t gfp_mask) +{ + char *tmpstr, *freestr; + int rc; + + if (!selinux_mls_enabled) + return -EINVAL; + + /* we need freestr because mls_context_to_sid will change + the value of tmpstr */ + tmpstr = freestr = kstrdup(str, gfp_mask); + if (!tmpstr) { + rc = -ENOMEM; + } else { + rc = mls_context_to_sid(':', &tmpstr, context, + NULL, SECSID_NULL); + kfree(freestr); + } + + return rc; +} + +/* * Copies the effective MLS range from `src' into `dst'. */ static inline int mls_scopy_context(struct context *dst, diff --git a/security/selinux/ss/mls.h b/security/selinux/ss/mls.h index 03de697c805..fbb42f07dd7 100644 --- a/security/selinux/ss/mls.h +++ b/security/selinux/ss/mls.h @@ -8,7 +8,7 @@ * * Support for enhanced MLS infrastructure. * - * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. + * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. */ #ifndef _SS_MLS_H_ @@ -27,6 +27,8 @@ int mls_context_to_sid(char oldc, struct sidtab *s, u32 def_sid); +int mls_from_string(char *str, struct context *context, gfp_t gfp_mask); + int mls_convert_context(struct policydb *oldp, struct policydb *newp, struct context *context); diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 61492485de8..7177e98df7f 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -7,12 +7,13 @@ * Updated: Trusted Computer Solutions, Inc. <dgoeddel@trustedcs.com> * * Support for enhanced MLS infrastructure. + * Support for context based audit filters. * * Updated: Frank Mayer <mayerf@tresys.com> and Karl MacMillan <kmacmillan@tresys.com> * * Added conditional policy language extensions * - * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. + * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. * Copyright (C) 2003 - 2004 Tresys Technology, LLC * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> * This program is free software; you can redistribute it and/or modify @@ -1811,3 +1812,235 @@ out: POLICY_RDUNLOCK; return rc; } + +struct selinux_audit_rule { + u32 au_seqno; + struct context au_ctxt; +}; + +void selinux_audit_rule_free(struct selinux_audit_rule *rule) +{ + if (rule) { + context_destroy(&rule->au_ctxt); + kfree(rule); + } +} + +int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, + struct selinux_audit_rule **rule) +{ + struct selinux_audit_rule *tmprule; + struct role_datum *roledatum; + struct type_datum *typedatum; + struct user_datum *userdatum; + int rc = 0; + + *rule = NULL; + + if (!ss_initialized) + return -ENOTSUPP; + + switch (field) { + case AUDIT_SE_USER: + case AUDIT_SE_ROLE: + case AUDIT_SE_TYPE: + /* only 'equals' and 'not equals' fit user, role, and type */ + if (op != AUDIT_EQUAL && op != AUDIT_NOT_EQUAL) + return -EINVAL; + break; + case AUDIT_SE_SEN: + case AUDIT_SE_CLR: + /* we do not allow a range, indicated by the presense of '-' */ + if (strchr(rulestr, '-')) + return -EINVAL; + break; + default: + /* only the above fields are valid */ + return -EINVAL; + } + + tmprule = kzalloc(sizeof(struct selinux_audit_rule), GFP_KERNEL); + if (!tmprule) + return -ENOMEM; + + context_init(&tmprule->au_ctxt); + + POLICY_RDLOCK; + + tmprule->au_seqno = latest_granting; + + switch (field) { + case AUDIT_SE_USER: + userdatum = hashtab_search(policydb.p_users.table, rulestr); + if (!userdatum) + rc = -EINVAL; + else + tmprule->au_ctxt.user = userdatum->value; + break; + case AUDIT_SE_ROLE: + roledatum = hashtab_search(policydb.p_roles.table, rulestr); + if (!roledatum) + rc = -EINVAL; + else + tmprule->au_ctxt.role = roledatum->value; + break; + case AUDIT_SE_TYPE: + typedatum = hashtab_search(policydb.p_types.table, rulestr); + if (!typedatum) + rc = -EINVAL; + else + tmprule->au_ctxt.type = typedatum->value; + break; + case AUDIT_SE_SEN: + case AUDIT_SE_CLR: + rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC); + break; + } + + POLICY_RDUNLOCK; + + if (rc) { + selinux_audit_rule_free(tmprule); + tmprule = NULL; + } + + *rule = tmprule; + + return rc; +} + +int selinux_audit_rule_match(u32 ctxid, u32 field, u32 op, + struct selinux_audit_rule *rule, + struct audit_context *actx) +{ + struct context *ctxt; + struct mls_level *level; + int match = 0; + + if (!rule) { + audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, + "selinux_audit_rule_match: missing rule\n"); + return -ENOENT; + } + + POLICY_RDLOCK; + + if (rule->au_seqno < latest_granting) { + audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, + "selinux_audit_rule_match: stale rule\n"); + match = -ESTALE; + goto out; + } + + ctxt = sidtab_search(&sidtab, ctxid); + if (!ctxt) { + audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, + "selinux_audit_rule_match: unrecognized SID %d\n", + ctxid); + match = -ENOENT; + goto out; + } + + /* a field/op pair that is not caught here will simply fall through + without a match */ + switch (field) { + case AUDIT_SE_USER: + switch (op) { + case AUDIT_EQUAL: + match = (ctxt->user == rule->au_ctxt.user); + break; + case AUDIT_NOT_EQUAL: + match = (ctxt->user != rule->au_ctxt.user); + break; + } + break; + case AUDIT_SE_ROLE: + switch (op) { + case AUDIT_EQUAL: + match = (ctxt->role == rule->au_ctxt.role); + break; + case AUDIT_NOT_EQUAL: + match = (ctxt->role != rule->au_ctxt.role); + break; + } + break; + case AUDIT_SE_TYPE: + switch (op) { + case AUDIT_EQUAL: + match = (ctxt->type == rule->au_ctxt.type); + break; + case AUDIT_NOT_EQUAL: + match = (ctxt->type != rule->au_ctxt.type); + break; + } + break; + case AUDIT_SE_SEN: + case AUDIT_SE_CLR: + level = (op == AUDIT_SE_SEN ? + &ctxt->range.level[0] : &ctxt->range.level[1]); + switch (op) { + case AUDIT_EQUAL: + match = mls_level_eq(&rule->au_ctxt.range.level[0], + level); + break; + case AUDIT_NOT_EQUAL: + match = !mls_level_eq(&rule->au_ctxt.range.level[0], + level); + break; + case AUDIT_LESS_THAN: + match = (mls_level_dom(&rule->au_ctxt.range.level[0], + level) && + !mls_level_eq(&rule->au_ctxt.range.level[0], + level)); + break; + case AUDIT_LESS_THAN_OR_EQUAL: + match = mls_level_dom(&rule->au_ctxt.range.level[0], + level); + break; + case AUDIT_GREATER_THAN: + match = (mls_level_dom(level, + &rule->au_ctxt.range.level[0]) && + !mls_level_eq(level, + &rule->au_ctxt.range.level[0])); + break; + case AUDIT_GREATER_THAN_OR_EQUAL: + match = mls_level_dom(level, + &rule->au_ctxt.range.level[0]); + break; + } + } + +out: + POLICY_RDUNLOCK; + return match; +} + +static int (*aurule_callback)(void) = NULL; + +static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid, + u16 class, u32 perms, u32 *retained) +{ + int err = 0; + + if (event == AVC_CALLBACK_RESET && aurule_callback) + err = aurule_callback(); + return err; +} + +static int __init aurule_init(void) +{ + int err; + + err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET, + SECSID_NULL, SECSID_NULL, SECCLASS_NULL, 0); + if (err) + panic("avc_add_callback() failed, error %d\n", err); + + return err; +} +__initcall(aurule_init); + +void selinux_audit_set_callback(int (*callback)(void)) +{ + aurule_callback = callback; +} |