diff options
Diffstat (limited to 'security/selinux/ss/services.c')
-rw-r--r-- | security/selinux/ss/services.c | 142 |
1 files changed, 120 insertions, 22 deletions
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 500e6f78e115..ff17820d35ec 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -22,6 +22,11 @@ * * Added validation of kernel classes and permissions * + * Updated: KaiGai Kohei <kaigai@ak.jp.nec.com> + * + * Added support for bounds domain and audit messaged on masked permissions + * + * Copyright (C) 2008, 2009 NEC Corporation * Copyright (C) 2006, 2007 Hewlett-Packard Development Company, L.P. * Copyright (C) 2004-2006 Trusted Computer Solutions, Inc. * Copyright (C) 2003 - 2004, 2006 Tresys Technology, LLC @@ -279,6 +284,95 @@ mls_ops: } /* + * security_dump_masked_av - dumps masked permissions during + * security_compute_av due to RBAC, MLS/Constraint and Type bounds. + */ +static int dump_masked_av_helper(void *k, void *d, void *args) +{ + struct perm_datum *pdatum = d; + char **permission_names = args; + + BUG_ON(pdatum->value < 1 || pdatum->value > 32); + + permission_names[pdatum->value - 1] = (char *)k; + + return 0; +} + +static void security_dump_masked_av(struct context *scontext, + struct context *tcontext, + u16 tclass, + u32 permissions, + const char *reason) +{ + struct common_datum *common_dat; + struct class_datum *tclass_dat; + struct audit_buffer *ab; + char *tclass_name; + char *scontext_name = NULL; + char *tcontext_name = NULL; + char *permission_names[32]; + int index, length; + bool need_comma = false; + + if (!permissions) + return; + + tclass_name = policydb.p_class_val_to_name[tclass - 1]; + tclass_dat = policydb.class_val_to_struct[tclass - 1]; + common_dat = tclass_dat->comdatum; + + /* init permission_names */ + if (common_dat && + hashtab_map(common_dat->permissions.table, + dump_masked_av_helper, permission_names) < 0) + goto out; + + if (hashtab_map(tclass_dat->permissions.table, + dump_masked_av_helper, permission_names) < 0) + goto out; + + /* get scontext/tcontext in text form */ + if (context_struct_to_string(scontext, + &scontext_name, &length) < 0) + goto out; + + if (context_struct_to_string(tcontext, + &tcontext_name, &length) < 0) + goto out; + + /* audit a message */ + ab = audit_log_start(current->audit_context, + GFP_ATOMIC, AUDIT_SELINUX_ERR); + if (!ab) + goto out; + + audit_log_format(ab, "op=security_compute_av reason=%s " + "scontext=%s tcontext=%s tclass=%s perms=", + reason, scontext_name, tcontext_name, tclass_name); + + for (index = 0; index < 32; index++) { + u32 mask = (1 << index); + + if ((mask & permissions) == 0) + continue; + + audit_log_format(ab, "%s%s", + need_comma ? "," : "", + permission_names[index] + ? permission_names[index] : "????"); + need_comma = true; + } + audit_log_end(ab); +out: + /* release scontext/tcontext */ + kfree(tcontext_name); + kfree(scontext_name); + + return; +} + +/* * security_boundary_permission - drops violated permissions * on boundary constraint. */ @@ -347,28 +441,12 @@ static void type_attribute_bounds_av(struct context *scontext, } if (masked) { - struct audit_buffer *ab; - char *stype_name - = policydb.p_type_val_to_name[source->value - 1]; - char *ttype_name - = policydb.p_type_val_to_name[target->value - 1]; - char *tclass_name - = policydb.p_class_val_to_name[tclass - 1]; - /* mask violated permissions */ avd->allowed &= ~masked; - /* notice to userspace via audit message */ - ab = audit_log_start(current->audit_context, - GFP_ATOMIC, AUDIT_SELINUX_ERR); - if (!ab) - return; - - audit_log_format(ab, "av boundary violation: " - "source=%s target=%s tclass=%s", - stype_name, ttype_name, tclass_name); - avc_dump_av(ab, tclass, masked); - audit_log_end(ab); + /* audit masked permissions */ + security_dump_masked_av(scontext, tcontext, + tclass, masked, "bounds"); } } @@ -480,7 +558,7 @@ static int context_struct_compute_av(struct context *scontext, if ((constraint->permissions & (avd->allowed)) && !constraint_expr_eval(scontext, tcontext, NULL, constraint->expr)) { - avd->allowed = (avd->allowed) & ~(constraint->permissions); + avd->allowed &= ~(constraint->permissions); } constraint = constraint->next; } @@ -499,8 +577,8 @@ static int context_struct_compute_av(struct context *scontext, break; } if (!ra) - avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION | - PROCESS__DYNTRANSITION); + avd->allowed &= ~(PROCESS__TRANSITION | + PROCESS__DYNTRANSITION); } /* @@ -687,6 +765,26 @@ int security_bounded_transition(u32 old_sid, u32 new_sid) } index = type->bounds; } + + if (rc) { + char *old_name = NULL; + char *new_name = NULL; + int length; + + if (!context_struct_to_string(old_context, + &old_name, &length) && + !context_struct_to_string(new_context, + &new_name, &length)) { + audit_log(current->audit_context, + GFP_ATOMIC, AUDIT_SELINUX_ERR, + "op=security_bounded_transition " + "result=denied " + "oldcontext=%s newcontext=%s", + old_name, new_name); + } + kfree(new_name); + kfree(old_name); + } out: read_unlock(&policy_rwlock); |