diff options
Diffstat (limited to 'security/selinux/ss/services.c')
| -rw-r--r-- | security/selinux/ss/services.c | 2577 |
1 files changed, 2015 insertions, 562 deletions
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 44eb4d74908..4bca49414a4 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -2,32 +2,58 @@ * Implementation of the security services. * * Authors : Stephen Smalley, <sds@epoch.ncsc.mil> - * James Morris <jmorris@redhat.com> + * James Morris <jmorris@redhat.com> * * 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 + * Added conditional policy language extensions * - * Copyright (C) 2004-2005 Trusted Computer Solutions, Inc. - * Copyright (C) 2003 - 2004 Tresys Technology, LLC + * Updated: Hewlett-Packard <paul@paul-moore.com> + * + * Added support for NetLabel + * Added support for the policy capability bitmap + * + * Updated: Chad Sellers <csellers@tresys.com> + * + * 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 + * + * Updated: Guido Trentalancia <guido@trentalancia.com> + * + * Added support for runtime switching of the policy type + * + * 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 * Copyright (C) 2003 Red Hat, Inc., James Morris <jmorris@redhat.com> * This program is free software; you can redistribute it and/or modify - * it under the terms of the GNU General Public License as published by + * it under the terms of the GNU General Public License as published by * the Free Software Foundation, version 2. */ #include <linux/kernel.h> #include <linux/slab.h> #include <linux/string.h> #include <linux/spinlock.h> +#include <linux/rcupdate.h> #include <linux/errno.h> #include <linux/in.h> #include <linux/sched.h> #include <linux/audit.h> -#include <asm/semaphore.h> +#include <linux/mutex.h> +#include <linux/selinux.h> +#include <linux/flex_array.h> +#include <linux/vmalloc.h> +#include <net/netlabel.h> + #include "flask.h" #include "avc.h" #include "avc_ss.h" @@ -38,23 +64,21 @@ #include "services.h" #include "conditional.h" #include "mls.h" +#include "objsec.h" +#include "netlabel.h" +#include "xfrm.h" +#include "ebitmap.h" +#include "audit.h" -extern void selnl_notify_policyload(u32 seqno); -unsigned int policydb_loaded_version; +int selinux_policycap_netpeer; +int selinux_policycap_openperm; +int selinux_policycap_alwaysnetwork; static DEFINE_RWLOCK(policy_rwlock); -#define POLICY_RDLOCK read_lock(&policy_rwlock) -#define POLICY_WRLOCK write_lock_irq(&policy_rwlock) -#define POLICY_RDUNLOCK read_unlock(&policy_rwlock) -#define POLICY_WRUNLOCK write_unlock_irq(&policy_rwlock) - -static DECLARE_MUTEX(load_sem); -#define LOAD_LOCK down(&load_sem) -#define LOAD_UNLOCK up(&load_sem) static struct sidtab sidtab; struct policydb policydb; -int ss_initialized = 0; +int ss_initialized; /* * The largest sequence number that has been used when @@ -62,12 +86,177 @@ int ss_initialized = 0; * The sequence number only changes when a policy change * occurs. */ -static u32 latest_granting = 0; +static u32 latest_granting; /* Forward declaration. */ static int context_struct_to_string(struct context *context, char **scontext, u32 *scontext_len); +static void context_struct_compute_av(struct context *scontext, + struct context *tcontext, + u16 tclass, + struct av_decision *avd); + +struct selinux_mapping { + u16 value; /* policy value */ + unsigned num_perms; + u32 perms[sizeof(u32) * 8]; +}; + +static struct selinux_mapping *current_mapping; +static u16 current_mapping_size; + +static int selinux_set_mapping(struct policydb *pol, + struct security_class_mapping *map, + struct selinux_mapping **out_map_p, + u16 *out_map_size) +{ + struct selinux_mapping *out_map = NULL; + size_t size = sizeof(struct selinux_mapping); + u16 i, j; + unsigned k; + bool print_unknown_handle = false; + + /* Find number of classes in the input mapping */ + if (!map) + return -EINVAL; + i = 0; + while (map[i].name) + i++; + + /* Allocate space for the class records, plus one for class zero */ + out_map = kcalloc(++i, size, GFP_ATOMIC); + if (!out_map) + return -ENOMEM; + + /* Store the raw class and permission values */ + j = 0; + while (map[j].name) { + struct security_class_mapping *p_in = map + (j++); + struct selinux_mapping *p_out = out_map + j; + + /* An empty class string skips ahead */ + if (!strcmp(p_in->name, "")) { + p_out->num_perms = 0; + continue; + } + + p_out->value = string_to_security_class(pol, p_in->name); + if (!p_out->value) { + printk(KERN_INFO + "SELinux: Class %s not defined in policy.\n", + p_in->name); + if (pol->reject_unknown) + goto err; + p_out->num_perms = 0; + print_unknown_handle = true; + continue; + } + + k = 0; + while (p_in->perms && p_in->perms[k]) { + /* An empty permission string skips ahead */ + if (!*p_in->perms[k]) { + k++; + continue; + } + p_out->perms[k] = string_to_av_perm(pol, p_out->value, + p_in->perms[k]); + if (!p_out->perms[k]) { + printk(KERN_INFO + "SELinux: Permission %s in class %s not defined in policy.\n", + p_in->perms[k], p_in->name); + if (pol->reject_unknown) + goto err; + print_unknown_handle = true; + } + + k++; + } + p_out->num_perms = k; + } + + if (print_unknown_handle) + printk(KERN_INFO "SELinux: the above unknown classes and permissions will be %s\n", + pol->allow_unknown ? "allowed" : "denied"); + + *out_map_p = out_map; + *out_map_size = i; + return 0; +err: + kfree(out_map); + return -EINVAL; +} + +/* + * Get real, policy values from mapped values + */ + +static u16 unmap_class(u16 tclass) +{ + if (tclass < current_mapping_size) + return current_mapping[tclass].value; + + return tclass; +} + +/* + * Get kernel value for class from its policy value + */ +static u16 map_class(u16 pol_value) +{ + u16 i; + + for (i = 1; i < current_mapping_size; i++) { + if (current_mapping[i].value == pol_value) + return i; + } + + return SECCLASS_NULL; +} + +static void map_decision(u16 tclass, struct av_decision *avd, + int allow_unknown) +{ + if (tclass < current_mapping_size) { + unsigned i, n = current_mapping[tclass].num_perms; + u32 result; + + for (i = 0, result = 0; i < n; i++) { + if (avd->allowed & current_mapping[tclass].perms[i]) + result |= 1<<i; + if (allow_unknown && !current_mapping[tclass].perms[i]) + result |= 1<<i; + } + avd->allowed = result; + + for (i = 0, result = 0; i < n; i++) + if (avd->auditallow & current_mapping[tclass].perms[i]) + result |= 1<<i; + avd->auditallow = result; + + for (i = 0, result = 0; i < n; i++) { + if (avd->auditdeny & current_mapping[tclass].perms[i]) + result |= 1<<i; + if (!allow_unknown && !current_mapping[tclass].perms[i]) + result |= 1<<i; + } + /* + * In case the kernel has a bug and requests a permission + * between num_perms and the maximum permission number, we + * should audit that denial + */ + for (; i < (sizeof(u32)*8); i++) + result |= 1<<i; + avd->auditdeny = result; + } +} + +int security_mls_enabled(void) +{ + return policydb.mls_enabled; +} + /* * Return the boolean value of a constraint expression * when it is applied to the specified source and target @@ -101,15 +290,15 @@ static int constraint_expr_eval(struct context *scontext, case CEXPR_AND: BUG_ON(sp < 1); sp--; - s[sp] &= s[sp+1]; + s[sp] &= s[sp + 1]; break; case CEXPR_OR: BUG_ON(sp < 1); sp--; - s[sp] |= s[sp+1]; + s[sp] |= s[sp + 1]; break; case CEXPR_ATTR: - if (sp == (CEXPR_MAXDEPTH-1)) + if (sp == (CEXPR_MAXDEPTH - 1)) return 0; switch (e->attr) { case CEXPR_USER: @@ -135,10 +324,10 @@ static int constraint_expr_eval(struct context *scontext, val1 - 1); continue; case CEXPR_INCOMP: - s[++sp] = ( !ebitmap_get_bit(&r1->dominates, - val2 - 1) && - !ebitmap_get_bit(&r2->dominates, - val1 - 1) ); + s[++sp] = (!ebitmap_get_bit(&r1->dominates, + val2 - 1) && + !ebitmap_get_bit(&r2->dominates, + val1 - 1)); continue; default: break; @@ -254,15 +443,184 @@ mls_ops: } /* - * Compute access vectors based on a context structure pair for - * the permissions in a particular class. + * 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; + u32 length; + bool need_comma = false; + + if (!permissions) + return; + + tclass_name = sym_name(&policydb, SYM_CLASSES, 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. */ -static int context_struct_compute_av(struct context *scontext, +static void type_attribute_bounds_av(struct context *scontext, struct context *tcontext, u16 tclass, - u32 requested, struct av_decision *avd) { + struct context lo_scontext; + struct context lo_tcontext; + struct av_decision lo_avd; + struct type_datum *source; + struct type_datum *target; + u32 masked = 0; + + source = flex_array_get_ptr(policydb.type_val_to_struct_array, + scontext->type - 1); + BUG_ON(!source); + + target = flex_array_get_ptr(policydb.type_val_to_struct_array, + tcontext->type - 1); + BUG_ON(!target); + + if (source->bounds) { + memset(&lo_avd, 0, sizeof(lo_avd)); + + memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); + lo_scontext.type = source->bounds; + + context_struct_compute_av(&lo_scontext, + tcontext, + tclass, + &lo_avd); + if ((lo_avd.allowed & avd->allowed) == avd->allowed) + return; /* no masked permission */ + masked = ~lo_avd.allowed & avd->allowed; + } + + if (target->bounds) { + memset(&lo_avd, 0, sizeof(lo_avd)); + + memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); + lo_tcontext.type = target->bounds; + + context_struct_compute_av(scontext, + &lo_tcontext, + tclass, + &lo_avd); + if ((lo_avd.allowed & avd->allowed) == avd->allowed) + return; /* no masked permission */ + masked = ~lo_avd.allowed & avd->allowed; + } + + if (source->bounds && target->bounds) { + memset(&lo_avd, 0, sizeof(lo_avd)); + /* + * lo_scontext and lo_tcontext are already + * set up. + */ + + context_struct_compute_av(&lo_scontext, + &lo_tcontext, + tclass, + &lo_avd); + if ((lo_avd.allowed & avd->allowed) == avd->allowed) + return; /* no masked permission */ + masked = ~lo_avd.allowed & avd->allowed; + } + + if (masked) { + /* mask violated permissions */ + avd->allowed &= ~masked; + + /* audit masked permissions */ + security_dump_masked_av(scontext, tcontext, + tclass, masked, "bounds"); + } +} + +/* + * Compute access vectors based on a context structure pair for + * the permissions in a particular class. + */ +static void context_struct_compute_av(struct context *scontext, + struct context *tcontext, + u16 tclass, + struct av_decision *avd) +{ struct constraint_node *constraint; struct role_allow *ra; struct avtab_key avkey; @@ -272,32 +630,17 @@ static int context_struct_compute_av(struct context *scontext, struct ebitmap_node *snode, *tnode; unsigned int i, j; - /* - * Remap extended Netlink classes for old policy versions. - * Do this here rather than socket_type_to_security_class() - * in case a newer policy version is loaded, allowing sockets - * to remain in the correct class. - */ - if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS) - if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET && - tclass <= SECCLASS_NETLINK_DNRT_SOCKET) - tclass = SECCLASS_NETLINK_SOCKET; - - if (!tclass || tclass > policydb.p_classes.nprim) { - printk(KERN_ERR "security_compute_av: unrecognized class %d\n", - tclass); - return -EINVAL; - } - tclass_datum = policydb.class_val_to_struct[tclass - 1]; - - /* - * Initialize the access vectors to the default values. - */ avd->allowed = 0; - avd->decided = 0xffffffff; avd->auditallow = 0; avd->auditdeny = 0xffffffff; - avd->seqno = latest_granting; + + if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { + if (printk_ratelimit()) + printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass); + return; + } + + tclass_datum = policydb.class_val_to_struct[tclass - 1]; /* * If a specific type enforcement rule was defined for @@ -305,18 +648,16 @@ static int context_struct_compute_av(struct context *scontext, */ avkey.target_class = tclass; avkey.specified = AVTAB_AV; - sattr = &policydb.type_attr_map[scontext->type - 1]; - tattr = &policydb.type_attr_map[tcontext->type - 1]; - ebitmap_for_each_bit(sattr, snode, i) { - if (!ebitmap_node_get_bit(snode, i)) - continue; - ebitmap_for_each_bit(tattr, tnode, j) { - if (!ebitmap_node_get_bit(tnode, j)) - continue; + sattr = flex_array_get(policydb.type_attr_map_array, scontext->type - 1); + BUG_ON(!sattr); + tattr = flex_array_get(policydb.type_attr_map_array, tcontext->type - 1); + BUG_ON(!tattr); + ebitmap_for_each_positive_bit(sattr, snode, i) { + ebitmap_for_each_positive_bit(tattr, tnode, j) { avkey.source_type = i + 1; avkey.target_type = j + 1; for (node = avtab_search_node(&policydb.te_avtab, &avkey); - node != NULL; + node; node = avtab_search_node_next(node, avkey.specified)) { if (node->key.specified == AVTAB_ALLOWED) avd->allowed |= node->datum.data; @@ -341,7 +682,7 @@ 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; } @@ -351,8 +692,8 @@ static int context_struct_compute_av(struct context *scontext, * role is changing, then check the (current_role, new_role) * pair. */ - if (tclass == SECCLASS_PROCESS && - (avd->allowed & (PROCESS__TRANSITION | PROCESS__DYNTRANSITION)) && + if (tclass == policydb.process_class && + (avd->allowed & policydb.process_trans_perms) && scontext->role != tcontext->role) { for (ra = policydb.role_allow; ra; ra = ra->next) { if (scontext->role == ra->role && @@ -360,31 +701,36 @@ static int context_struct_compute_av(struct context *scontext, break; } if (!ra) - avd->allowed = (avd->allowed) & ~(PROCESS__TRANSITION | - PROCESS__DYNTRANSITION); + avd->allowed &= ~policydb.process_trans_perms; } - return 0; + /* + * If the given source and target types have boundary + * constraint, lazy checks have to mask any violated + * permission and notice it to userspace via audit. + */ + type_attribute_bounds_av(scontext, tcontext, + tclass, avd); } static int security_validtrans_handle_fail(struct context *ocontext, - struct context *ncontext, - struct context *tcontext, - u16 tclass) + struct context *ncontext, + struct context *tcontext, + u16 tclass) { char *o = NULL, *n = NULL, *t = NULL; u32 olen, nlen, tlen; - if (context_struct_to_string(ocontext, &o, &olen) < 0) + if (context_struct_to_string(ocontext, &o, &olen)) goto out; - if (context_struct_to_string(ncontext, &n, &nlen) < 0) + if (context_struct_to_string(ncontext, &n, &nlen)) goto out; - if (context_struct_to_string(tcontext, &t, &tlen) < 0) + if (context_struct_to_string(tcontext, &t, &tlen)) goto out; audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "security_validate_transition: denied for" - " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", - o, n, t, policydb.p_class_val_to_name[tclass-1]); + "security_validate_transition: denied for" + " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", + o, n, t, sym_name(&policydb, SYM_CLASSES, tclass-1)); out: kfree(o); kfree(n); @@ -396,34 +742,26 @@ out: } int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, - u16 tclass) + u16 orig_tclass) { struct context *ocontext; struct context *ncontext; struct context *tcontext; struct class_datum *tclass_datum; struct constraint_node *constraint; + u16 tclass; int rc = 0; if (!ss_initialized) return 0; - POLICY_RDLOCK; + read_lock(&policy_rwlock); - /* - * Remap extended Netlink classes for old policy versions. - * Do this here rather than socket_type_to_security_class() - * in case a newer policy version is loaded, allowing sockets - * to remain in the correct class. - */ - if (policydb_loaded_version < POLICYDB_VERSION_NLCLASS) - if (tclass >= SECCLASS_NETLINK_ROUTE_SOCKET && - tclass <= SECCLASS_NETLINK_DNRT_SOCKET) - tclass = SECCLASS_NETLINK_SOCKET; + tclass = unmap_class(orig_tclass); if (!tclass || tclass > policydb.p_classes.nprim) { - printk(KERN_ERR "security_validate_transition: " - "unrecognized class %d\n", tclass); + printk(KERN_ERR "SELinux: %s: unrecognized class %d\n", + __func__, tclass); rc = -EINVAL; goto out; } @@ -431,24 +769,24 @@ int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, ocontext = sidtab_search(&sidtab, oldsid); if (!ocontext) { - printk(KERN_ERR "security_validate_transition: " - " unrecognized SID %d\n", oldsid); + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, oldsid); rc = -EINVAL; goto out; } ncontext = sidtab_search(&sidtab, newsid); if (!ncontext) { - printk(KERN_ERR "security_validate_transition: " - " unrecognized SID %d\n", newsid); + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, newsid); rc = -EINVAL; goto out; } tcontext = sidtab_search(&sidtab, tasksid); if (!tcontext) { - printk(KERN_ERR "security_validate_transition: " - " unrecognized SID %d\n", tasksid); + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, tasksid); rc = -EINVAL; goto out; } @@ -456,72 +794,212 @@ int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, constraint = tclass_datum->validatetrans; while (constraint) { if (!constraint_expr_eval(ocontext, ncontext, tcontext, - constraint->expr)) { + constraint->expr)) { rc = security_validtrans_handle_fail(ocontext, ncontext, - tcontext, tclass); + tcontext, tclass); goto out; } constraint = constraint->next; } out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); + return rc; +} + +/* + * security_bounded_transition - check whether the given + * transition is directed to bounded, or not. + * It returns 0, if @newsid is bounded by @oldsid. + * Otherwise, it returns error code. + * + * @oldsid : current security identifier + * @newsid : destinated security identifier + */ +int security_bounded_transition(u32 old_sid, u32 new_sid) +{ + struct context *old_context, *new_context; + struct type_datum *type; + int index; + int rc; + + read_lock(&policy_rwlock); + + rc = -EINVAL; + old_context = sidtab_search(&sidtab, old_sid); + if (!old_context) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", + __func__, old_sid); + goto out; + } + + rc = -EINVAL; + new_context = sidtab_search(&sidtab, new_sid); + if (!new_context) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %u\n", + __func__, new_sid); + goto out; + } + + rc = 0; + /* type/domain unchanged */ + if (old_context->type == new_context->type) + goto out; + + index = new_context->type; + while (true) { + type = flex_array_get_ptr(policydb.type_val_to_struct_array, + index - 1); + BUG_ON(!type); + + /* not bounded anymore */ + rc = -EPERM; + if (!type->bounds) + break; + + /* @newsid is bounded by @oldsid */ + rc = 0; + if (type->bounds == old_context->type) + break; + + index = type->bounds; + } + + if (rc) { + char *old_name = NULL; + char *new_name = NULL; + u32 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); + return rc; } +static void avd_init(struct av_decision *avd) +{ + avd->allowed = 0; + avd->auditallow = 0; + avd->auditdeny = 0xffffffff; + avd->seqno = latest_granting; + avd->flags = 0; +} + + /** * security_compute_av - Compute access vector decisions. * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class - * @requested: requested permissions * @avd: access vector decisions * * Compute a set of access vector decisions based on the * SID pair (@ssid, @tsid) for the permissions in @tclass. - * Return -%EINVAL if any of the parameters are invalid or %0 - * if the access vector decisions were computed successfully. */ -int security_compute_av(u32 ssid, - u32 tsid, - u16 tclass, - u32 requested, - struct av_decision *avd) +void security_compute_av(u32 ssid, + u32 tsid, + u16 orig_tclass, + struct av_decision *avd) { + u16 tclass; struct context *scontext = NULL, *tcontext = NULL; - int rc = 0; - if (!ss_initialized) { - avd->allowed = 0xffffffff; - avd->decided = 0xffffffff; - avd->auditallow = 0; - avd->auditdeny = 0xffffffff; - avd->seqno = latest_granting; - return 0; + read_lock(&policy_rwlock); + avd_init(avd); + if (!ss_initialized) + goto allow; + + scontext = sidtab_search(&sidtab, ssid); + if (!scontext) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, ssid); + goto out; + } + + /* permissive domain? */ + if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) + avd->flags |= AVD_FLAGS_PERMISSIVE; + + tcontext = sidtab_search(&sidtab, tsid); + if (!tcontext) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, tsid); + goto out; } - POLICY_RDLOCK; + tclass = unmap_class(orig_tclass); + if (unlikely(orig_tclass && !tclass)) { + if (policydb.allow_unknown) + goto allow; + goto out; + } + context_struct_compute_av(scontext, tcontext, tclass, avd); + map_decision(orig_tclass, avd, policydb.allow_unknown); +out: + read_unlock(&policy_rwlock); + return; +allow: + avd->allowed = 0xffffffff; + goto out; +} + +void security_compute_av_user(u32 ssid, + u32 tsid, + u16 tclass, + struct av_decision *avd) +{ + struct context *scontext = NULL, *tcontext = NULL; + + read_lock(&policy_rwlock); + avd_init(avd); + if (!ss_initialized) + goto allow; scontext = sidtab_search(&sidtab, ssid); if (!scontext) { - printk(KERN_ERR "security_compute_av: unrecognized SID %d\n", - ssid); - rc = -EINVAL; + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, ssid); goto out; } + + /* permissive domain? */ + if (ebitmap_get_bit(&policydb.permissive_map, scontext->type)) + avd->flags |= AVD_FLAGS_PERMISSIVE; + tcontext = sidtab_search(&sidtab, tsid); if (!tcontext) { - printk(KERN_ERR "security_compute_av: unrecognized SID %d\n", - tsid); - rc = -EINVAL; + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, tsid); goto out; } - rc = context_struct_compute_av(scontext, tcontext, tclass, - requested, avd); -out: - POLICY_RDUNLOCK; - return rc; + if (unlikely(!tclass)) { + if (policydb.allow_unknown) + goto allow; + goto out; + } + + context_struct_compute_av(scontext, tcontext, tclass, avd); + out: + read_unlock(&policy_rwlock); + return; +allow: + avd->allowed = 0xffffffff; + goto out; } /* @@ -535,32 +1013,45 @@ static int context_struct_to_string(struct context *context, char **scontext, u3 { char *scontextp; - *scontext = NULL; + if (scontext) + *scontext = NULL; *scontext_len = 0; + if (context->len) { + *scontext_len = context->len; + if (scontext) { + *scontext = kstrdup(context->str, GFP_ATOMIC); + if (!(*scontext)) + return -ENOMEM; + } + return 0; + } + /* Compute the size of the context. */ - *scontext_len += strlen(policydb.p_user_val_to_name[context->user - 1]) + 1; - *scontext_len += strlen(policydb.p_role_val_to_name[context->role - 1]) + 1; - *scontext_len += strlen(policydb.p_type_val_to_name[context->type - 1]) + 1; + *scontext_len += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + 1; + *scontext_len += strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + 1; + *scontext_len += strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)) + 1; *scontext_len += mls_compute_context_len(context); + if (!scontext) + return 0; + /* Allocate space for the context; caller must free this space. */ scontextp = kmalloc(*scontext_len, GFP_ATOMIC); - if (!scontextp) { + if (!scontextp) return -ENOMEM; - } *scontext = scontextp; /* * Copy the user name, role name and type name into the context. */ sprintf(scontextp, "%s:%s:%s", - policydb.p_user_val_to_name[context->user - 1], - policydb.p_role_val_to_name[context->role - 1], - policydb.p_type_val_to_name[context->type - 1]); - scontextp += strlen(policydb.p_user_val_to_name[context->user - 1]) + - 1 + strlen(policydb.p_role_val_to_name[context->role - 1]) + - 1 + strlen(policydb.p_type_val_to_name[context->type - 1]); + sym_name(&policydb, SYM_USERS, context->user - 1), + sym_name(&policydb, SYM_ROLES, context->role - 1), + sym_name(&policydb, SYM_TYPES, context->type - 1)); + scontextp += strlen(sym_name(&policydb, SYM_USERS, context->user - 1)) + + 1 + strlen(sym_name(&policydb, SYM_ROLES, context->role - 1)) + + 1 + strlen(sym_name(&policydb, SYM_TYPES, context->type - 1)); mls_sid_to_context(context, &scontextp); @@ -571,98 +1062,105 @@ static int context_struct_to_string(struct context *context, char **scontext, u3 #include "initial_sid_to_string.h" -/** - * security_sid_to_context - Obtain a context for a given SID. - * @sid: security identifier, SID - * @scontext: security context - * @scontext_len: length in bytes - * - * Write the string representation of the context associated with @sid - * into a dynamically allocated string of the correct size. Set @scontext - * to point to this string and set @scontext_len to the length of the string. - */ -int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len) +const char *security_get_initial_sid_context(u32 sid) +{ + if (unlikely(sid > SECINITSID_NUM)) + return NULL; + return initial_sid_to_string[sid]; +} + +static int security_sid_to_context_core(u32 sid, char **scontext, + u32 *scontext_len, int force) { struct context *context; int rc = 0; + if (scontext) + *scontext = NULL; + *scontext_len = 0; + if (!ss_initialized) { if (sid <= SECINITSID_NUM) { char *scontextp; *scontext_len = strlen(initial_sid_to_string[sid]) + 1; - scontextp = kmalloc(*scontext_len,GFP_ATOMIC); + if (!scontext) + goto out; + scontextp = kmalloc(*scontext_len, GFP_ATOMIC); + if (!scontextp) { + rc = -ENOMEM; + goto out; + } strcpy(scontextp, initial_sid_to_string[sid]); *scontext = scontextp; goto out; } - printk(KERN_ERR "security_sid_to_context: called before initial " - "load_policy on unknown SID %d\n", sid); + printk(KERN_ERR "SELinux: %s: called before initial " + "load_policy on unknown SID %d\n", __func__, sid); rc = -EINVAL; goto out; } - POLICY_RDLOCK; - context = sidtab_search(&sidtab, sid); + read_lock(&policy_rwlock); + if (force) + context = sidtab_search_force(&sidtab, sid); + else + context = sidtab_search(&sidtab, sid); if (!context) { - printk(KERN_ERR "security_sid_to_context: unrecognized SID " - "%d\n", sid); + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, sid); rc = -EINVAL; goto out_unlock; } rc = context_struct_to_string(context, scontext, scontext_len); out_unlock: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); out: return rc; } -static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid) +/** + * security_sid_to_context - Obtain a context for a given SID. + * @sid: security identifier, SID + * @scontext: security context + * @scontext_len: length in bytes + * + * Write the string representation of the context associated with @sid + * into a dynamically allocated string of the correct size. Set @scontext + * to point to this string and set @scontext_len to the length of the string. + */ +int security_sid_to_context(u32 sid, char **scontext, u32 *scontext_len) +{ + return security_sid_to_context_core(sid, scontext, scontext_len, 0); +} + +int security_sid_to_context_force(u32 sid, char **scontext, u32 *scontext_len) +{ + return security_sid_to_context_core(sid, scontext, scontext_len, 1); +} + +/* + * Caveat: Mutates scontext. + */ +static int string_to_context_struct(struct policydb *pol, + struct sidtab *sidtabp, + char *scontext, + u32 scontext_len, + struct context *ctx, + u32 def_sid) { - char *scontext2; - struct context context; struct role_datum *role; struct type_datum *typdatum; struct user_datum *usrdatum; char *scontextp, *p, oldc; int rc = 0; - if (!ss_initialized) { - int i; - - for (i = 1; i < SECINITSID_NUM; i++) { - if (!strcmp(initial_sid_to_string[i], scontext)) { - *sid = i; - goto out; - } - } - *sid = SECINITSID_KERNEL; - goto out; - } - *sid = SECSID_NULL; - - /* Copy the string so that we can modify the copy as we parse it. - The string should already by null terminated, but we append a - null suffix to the copy to avoid problems with the existing - attr package, which doesn't view the null terminator as part - of the attribute value. */ - scontext2 = kmalloc(scontext_len+1,GFP_KERNEL); - if (!scontext2) { - rc = -ENOMEM; - goto out; - } - memcpy(scontext2, scontext, scontext_len); - scontext2[scontext_len] = 0; - - context_init(&context); - *sid = SECSID_NULL; - - POLICY_RDLOCK; + context_init(ctx); /* Parse the security context. */ rc = -EINVAL; - scontextp = (char *) scontext2; + scontextp = (char *) scontext; /* Extract the user. */ p = scontextp; @@ -670,15 +1168,15 @@ static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *s p++; if (*p == 0) - goto out_unlock; + goto out; *p++ = 0; - usrdatum = hashtab_search(policydb.p_users.table, scontextp); + usrdatum = hashtab_search(pol->p_users.table, scontextp); if (!usrdatum) - goto out_unlock; + goto out; - context.user = usrdatum->value; + ctx->user = usrdatum->value; /* Extract role. */ scontextp = p; @@ -686,14 +1184,14 @@ static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *s p++; if (*p == 0) - goto out_unlock; + goto out; *p++ = 0; - role = hashtab_search(policydb.p_roles.table, scontextp); + role = hashtab_search(pol->p_roles.table, scontextp); if (!role) - goto out_unlock; - context.role = role->value; + goto out; + ctx->role = role->value; /* Extract type. */ scontextp = p; @@ -702,33 +1200,87 @@ static int security_context_to_sid_core(char *scontext, u32 scontext_len, u32 *s oldc = *p; *p++ = 0; - typdatum = hashtab_search(policydb.p_types.table, scontextp); - if (!typdatum) - goto out_unlock; + typdatum = hashtab_search(pol->p_types.table, scontextp); + if (!typdatum || typdatum->attribute) + goto out; - context.type = typdatum->value; + ctx->type = typdatum->value; - rc = mls_context_to_sid(oldc, &p, &context, &sidtab, def_sid); + rc = mls_context_to_sid(pol, oldc, &p, ctx, sidtabp, def_sid); if (rc) - goto out_unlock; + goto out; - if ((p - scontext2) < scontext_len) { - rc = -EINVAL; - goto out_unlock; - } + rc = -EINVAL; + if ((p - scontext) < scontext_len) + goto out; /* Check the validity of the new context. */ - if (!policydb_context_isvalid(&policydb, &context)) { - rc = -EINVAL; - goto out_unlock; + if (!policydb_context_isvalid(pol, ctx)) + goto out; + rc = 0; +out: + if (rc) + context_destroy(ctx); + return rc; +} + +static int security_context_to_sid_core(const char *scontext, u32 scontext_len, + u32 *sid, u32 def_sid, gfp_t gfp_flags, + int force) +{ + char *scontext2, *str = NULL; + struct context context; + int rc = 0; + + /* An empty security context is never valid. */ + if (!scontext_len) + return -EINVAL; + + if (!ss_initialized) { + int i; + + for (i = 1; i < SECINITSID_NUM; i++) { + if (!strcmp(initial_sid_to_string[i], scontext)) { + *sid = i; + return 0; + } + } + *sid = SECINITSID_KERNEL; + return 0; + } + *sid = SECSID_NULL; + + /* Copy the string so that we can modify the copy as we parse it. */ + scontext2 = kmalloc(scontext_len + 1, gfp_flags); + if (!scontext2) + return -ENOMEM; + memcpy(scontext2, scontext, scontext_len); + scontext2[scontext_len] = 0; + + if (force) { + /* Save another copy for storing in uninterpreted form */ + rc = -ENOMEM; + str = kstrdup(scontext2, gfp_flags); + if (!str) + goto out; } - /* Obtain the new sid. */ + + read_lock(&policy_rwlock); + rc = string_to_context_struct(&policydb, &sidtab, scontext2, + scontext_len, &context, def_sid); + if (rc == -EINVAL && force) { + context.str = str; + context.len = scontext_len; + str = NULL; + } else if (rc) + goto out_unlock; rc = sidtab_context_to_sid(&sidtab, &context, sid); -out_unlock: - POLICY_RDUNLOCK; context_destroy(&context); - kfree(scontext2); +out_unlock: + read_unlock(&policy_rwlock); out: + kfree(scontext2); + kfree(str); return rc; } @@ -737,16 +1289,18 @@ out: * @scontext: security context * @scontext_len: length in bytes * @sid: security identifier, SID + * @gfp: context for the allocation * * Obtains a SID associated with the security context that * has the string representation specified by @scontext. * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient * memory is available, or 0 on success. */ -int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid) +int security_context_to_sid(const char *scontext, u32 scontext_len, u32 *sid, + gfp_t gfp) { return security_context_to_sid_core(scontext, scontext_len, - sid, SECSID_NULL); + sid, SECSID_NULL, gfp, 0); } /** @@ -756,20 +1310,29 @@ int security_context_to_sid(char *scontext, u32 scontext_len, u32 *sid) * @scontext: security context * @scontext_len: length in bytes * @sid: security identifier, SID - * @def_sid: default SID to assign on errror + * @def_sid: default SID to assign on error * * Obtains a SID associated with the security context that * has the string representation specified by @scontext. * The default SID is passed to the MLS layer to be used to allow * kernel labeling of the MLS field if the MLS field is not present * (for upgrading to MLS without full relabel). + * Implicitly forces adding of the context even if it cannot be mapped yet. * Returns -%EINVAL if the context is invalid, -%ENOMEM if insufficient * memory is available, or 0 on success. */ -int security_context_to_sid_default(char *scontext, u32 scontext_len, u32 *sid, u32 def_sid) +int security_context_to_sid_default(const char *scontext, u32 scontext_len, + u32 *sid, u32 def_sid, gfp_t gfp_flags) +{ + return security_context_to_sid_core(scontext, scontext_len, + sid, def_sid, gfp_flags, 1); +} + +int security_context_to_sid_force(const char *scontext, u32 scontext_len, + u32 *sid) { return security_context_to_sid_core(scontext, scontext_len, - sid, def_sid); + sid, SECSID_NULL, GFP_KERNEL, 1); } static int compute_sid_handle_invalid_context( @@ -781,18 +1344,18 @@ static int compute_sid_handle_invalid_context( char *s = NULL, *t = NULL, *n = NULL; u32 slen, tlen, nlen; - if (context_struct_to_string(scontext, &s, &slen) < 0) + if (context_struct_to_string(scontext, &s, &slen)) goto out; - if (context_struct_to_string(tcontext, &t, &tlen) < 0) + if (context_struct_to_string(tcontext, &t, &tlen)) goto out; - if (context_struct_to_string(newcontext, &n, &nlen) < 0) + if (context_struct_to_string(newcontext, &n, &nlen)) goto out; audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, "security_compute_sid: invalid context %s" " for scontext=%s" " tcontext=%s" " tclass=%s", - n, s, t, policydb.p_class_val_to_name[tclass-1]); + n, s, t, sym_name(&policydb, SYM_CLASSES, tclass-1)); out: kfree(s); kfree(t); @@ -802,22 +1365,52 @@ out: return -EACCES; } +static void filename_compute_type(struct policydb *p, struct context *newcontext, + u32 stype, u32 ttype, u16 tclass, + const char *objname) +{ + struct filename_trans ft; + struct filename_trans_datum *otype; + + /* + * Most filename trans rules are going to live in specific directories + * like /dev or /var/run. This bitmap will quickly skip rule searches + * if the ttype does not contain any rules. + */ + if (!ebitmap_get_bit(&p->filename_trans_ttypes, ttype)) + return; + + ft.stype = stype; + ft.ttype = ttype; + ft.tclass = tclass; + ft.name = objname; + + otype = hashtab_search(p->filename_trans, &ft); + if (otype) + newcontext->type = otype->otype; +} + static int security_compute_sid(u32 ssid, u32 tsid, - u16 tclass, + u16 orig_tclass, u32 specified, - u32 *out_sid) + const char *objname, + u32 *out_sid, + bool kern) { + struct class_datum *cladatum = NULL; struct context *scontext = NULL, *tcontext = NULL, newcontext; struct role_trans *roletr = NULL; struct avtab_key avkey; struct avtab_datum *avdatum; struct avtab_node *node; + u16 tclass; int rc = 0; + bool sock; if (!ss_initialized) { - switch (tclass) { - case SECCLASS_PROCESS: + switch (orig_tclass) { + case SECCLASS_PROCESS: /* kernel value */ *out_sid = ssid; break; default: @@ -827,31 +1420,47 @@ static int security_compute_sid(u32 ssid, goto out; } - POLICY_RDLOCK; + context_init(&newcontext); + + read_lock(&policy_rwlock); + + if (kern) { + tclass = unmap_class(orig_tclass); + sock = security_is_socket_class(orig_tclass); + } else { + tclass = orig_tclass; + sock = security_is_socket_class(map_class(tclass)); + } scontext = sidtab_search(&sidtab, ssid); if (!scontext) { - printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n", - ssid); + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, ssid); rc = -EINVAL; goto out_unlock; } tcontext = sidtab_search(&sidtab, tsid); if (!tcontext) { - printk(KERN_ERR "security_compute_sid: unrecognized SID %d\n", - tsid); + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, tsid); rc = -EINVAL; goto out_unlock; } - context_init(&newcontext); + if (tclass && tclass <= policydb.p_classes.nprim) + cladatum = policydb.class_val_to_struct[tclass - 1]; /* Set the user identity. */ switch (specified) { case AVTAB_TRANSITION: case AVTAB_CHANGE: - /* Use the process user identity. */ - newcontext.user = scontext->user; + if (cladatum && cladatum->default_user == DEFAULT_TARGET) { + newcontext.user = tcontext->user; + } else { + /* notice this gets both DEFAULT_SOURCE and unset */ + /* Use the process user identity. */ + newcontext.user = scontext->user; + } break; case AVTAB_MEMBER: /* Use the related object owner. */ @@ -859,18 +1468,31 @@ static int security_compute_sid(u32 ssid, break; } - /* Set the role and type to default values. */ - switch (tclass) { - case SECCLASS_PROCESS: - /* Use the current role and type of process. */ + /* Set the role to default values. */ + if (cladatum && cladatum->default_role == DEFAULT_SOURCE) { newcontext.role = scontext->role; + } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) { + newcontext.role = tcontext->role; + } else { + if ((tclass == policydb.process_class) || (sock == true)) + newcontext.role = scontext->role; + else + newcontext.role = OBJECT_R_VAL; + } + + /* Set the type to default values. */ + if (cladatum && cladatum->default_type == DEFAULT_SOURCE) { newcontext.type = scontext->type; - break; - default: - /* Use the well-defined object role. */ - newcontext.role = OBJECT_R_VAL; - /* Use the type of the related object. */ + } else if (cladatum && cladatum->default_type == DEFAULT_TARGET) { newcontext.type = tcontext->type; + } else { + if ((tclass == policydb.process_class) || (sock == true)) { + /* Use the type of process. */ + newcontext.type = scontext->type; + } else { + /* Use the type of the related object. */ + newcontext.type = tcontext->type; + } } /* Look for a type transition/member/change rule. */ @@ -881,9 +1503,9 @@ static int security_compute_sid(u32 ssid, avdatum = avtab_search(&policydb.te_avtab, &avkey); /* If no permanent rule, also check for enabled conditional rules */ - if(!avdatum) { + if (!avdatum) { node = avtab_search_node(&policydb.te_cond_avtab, &avkey); - for (; node != NULL; node = avtab_search_node_next(node, specified)) { + for (; node; node = avtab_search_node_next(node, specified)) { if (node->key.specified & AVTAB_ENABLED) { avdatum = &node->datum; break; @@ -896,29 +1518,29 @@ static int security_compute_sid(u32 ssid, newcontext.type = avdatum->data; } + /* if we have a objname this is a file trans check so check those rules */ + if (objname) + filename_compute_type(&policydb, &newcontext, scontext->type, + tcontext->type, tclass, objname); + /* Check for class-specific changes. */ - switch (tclass) { - case SECCLASS_PROCESS: - if (specified & AVTAB_TRANSITION) { - /* Look for a role transition rule. */ - for (roletr = policydb.role_tr; roletr; - roletr = roletr->next) { - if (roletr->role == scontext->role && - roletr->type == tcontext->type) { - /* Use the role transition rule. */ - newcontext.role = roletr->new_role; - break; - } + if (specified & AVTAB_TRANSITION) { + /* Look for a role transition rule. */ + for (roletr = policydb.role_tr; roletr; roletr = roletr->next) { + if ((roletr->role == scontext->role) && + (roletr->type == tcontext->type) && + (roletr->tclass == tclass)) { + /* Use the role transition rule. */ + newcontext.role = roletr->new_role; + break; } } - break; - default: - break; } /* Set the MLS attributes. This is done last because it may allocate memory. */ - rc = mls_compute_sid(scontext, tcontext, tclass, specified, &newcontext); + rc = mls_compute_sid(scontext, tcontext, tclass, specified, + &newcontext, sock); if (rc) goto out_unlock; @@ -934,7 +1556,7 @@ static int security_compute_sid(u32 ssid, /* Obtain the sid for the context. */ rc = sidtab_context_to_sid(&sidtab, &newcontext, out_sid); out_unlock: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); context_destroy(&newcontext); out: return rc; @@ -953,12 +1575,18 @@ out: * if insufficient memory is available, or %0 if the new SID was * computed successfully. */ -int security_transition_sid(u32 ssid, - u32 tsid, - u16 tclass, - u32 *out_sid) +int security_transition_sid(u32 ssid, u32 tsid, u16 tclass, + const struct qstr *qstr, u32 *out_sid) +{ + return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, + qstr ? qstr->name : NULL, out_sid, true); +} + +int security_transition_sid_user(u32 ssid, u32 tsid, u16 tclass, + const char *objname, u32 *out_sid) { - return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, out_sid); + return security_compute_sid(ssid, tsid, tclass, AVTAB_TRANSITION, + objname, out_sid, false); } /** @@ -979,7 +1607,8 @@ int security_member_sid(u32 ssid, u16 tclass, u32 *out_sid) { - return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid); + return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL, + out_sid, false); } /** @@ -1000,90 +1629,8 @@ int security_change_sid(u32 ssid, u16 tclass, u32 *out_sid) { - return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid); -} - -/* - * Verify that each permission that is defined under the - * existing policy is still defined with the same value - * in the new policy. - */ -static int validate_perm(void *key, void *datum, void *p) -{ - struct hashtab *h; - struct perm_datum *perdatum, *perdatum2; - int rc = 0; - - - h = p; - perdatum = datum; - - perdatum2 = hashtab_search(h, key); - if (!perdatum2) { - printk(KERN_ERR "security: permission %s disappeared", - (char *)key); - rc = -ENOENT; - goto out; - } - if (perdatum->value != perdatum2->value) { - printk(KERN_ERR "security: the value of permission %s changed", - (char *)key); - rc = -EINVAL; - } -out: - return rc; -} - -/* - * Verify that each class that is defined under the - * existing policy is still defined with the same - * attributes in the new policy. - */ -static int validate_class(void *key, void *datum, void *p) -{ - struct policydb *newp; - struct class_datum *cladatum, *cladatum2; - int rc; - - newp = p; - cladatum = datum; - - cladatum2 = hashtab_search(newp->p_classes.table, key); - if (!cladatum2) { - printk(KERN_ERR "security: class %s disappeared\n", - (char *)key); - rc = -ENOENT; - goto out; - } - if (cladatum->value != cladatum2->value) { - printk(KERN_ERR "security: the value of class %s changed\n", - (char *)key); - rc = -EINVAL; - goto out; - } - if ((cladatum->comdatum && !cladatum2->comdatum) || - (!cladatum->comdatum && cladatum2->comdatum)) { - printk(KERN_ERR "security: the inherits clause for the access " - "vector definition for class %s changed\n", (char *)key); - rc = -EINVAL; - goto out; - } - if (cladatum->comdatum) { - rc = hashtab_map(cladatum->comdatum->permissions.table, validate_perm, - cladatum2->comdatum->permissions.table); - if (rc) { - printk(" in the access vector definition for class " - "%s\n", (char *)key); - goto out; - } - } - rc = hashtab_map(cladatum->permissions.table, validate_perm, - cladatum2->permissions.table); - if (rc) - printk(" in access vector definition for class %s\n", - (char *)key); -out: - return rc; + return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL, + out_sid, false); } /* Clone the SID into the new SID table. */ @@ -1093,24 +1640,25 @@ static int clone_sid(u32 sid, { struct sidtab *s = arg; - return sidtab_insert(s, sid, context); + if (sid > SECINITSID_NUM) + return sidtab_insert(s, sid, context); + else + return 0; } static inline int convert_context_handle_invalid_context(struct context *context) { - int rc = 0; + char *s; + u32 len; - if (selinux_enforcing) { - rc = -EINVAL; - } else { - char *s; - u32 len; + if (selinux_enforcing) + return -EINVAL; - context_struct_to_string(context, &s, &len); - printk(KERN_ERR "security: context %s is invalid\n", s); + if (!context_struct_to_string(context, &s, &len)) { + printk(KERN_WARNING "SELinux: Context %s would be invalid if enforcing\n", s); kfree(s); } - return rc; + return 0; } struct convert_context_args { @@ -1131,48 +1679,112 @@ static int convert_context(u32 key, { struct convert_context_args *args; struct context oldc; + struct ocontext *oc; + struct mls_range *range; struct role_datum *role; struct type_datum *typdatum; struct user_datum *usrdatum; char *s; u32 len; - int rc; + int rc = 0; + + if (key <= SECINITSID_NUM) + goto out; args = p; + if (c->str) { + struct context ctx; + + rc = -ENOMEM; + s = kstrdup(c->str, GFP_KERNEL); + if (!s) + goto out; + + rc = string_to_context_struct(args->newp, NULL, s, + c->len, &ctx, SECSID_NULL); + kfree(s); + if (!rc) { + printk(KERN_INFO "SELinux: Context %s became valid (mapped).\n", + c->str); + /* Replace string with mapped representation. */ + kfree(c->str); + memcpy(c, &ctx, sizeof(*c)); + goto out; + } else if (rc == -EINVAL) { + /* Retain string representation for later mapping. */ + rc = 0; + goto out; + } else { + /* Other error condition, e.g. ENOMEM. */ + printk(KERN_ERR "SELinux: Unable to map context %s, rc = %d.\n", + c->str, -rc); + goto out; + } + } + rc = context_cpy(&oldc, c); if (rc) goto out; - rc = -EINVAL; - /* Convert the user. */ + rc = -EINVAL; usrdatum = hashtab_search(args->newp->p_users.table, - args->oldp->p_user_val_to_name[c->user - 1]); - if (!usrdatum) { + sym_name(args->oldp, SYM_USERS, c->user - 1)); + if (!usrdatum) goto bad; - } c->user = usrdatum->value; /* Convert the role. */ + rc = -EINVAL; role = hashtab_search(args->newp->p_roles.table, - args->oldp->p_role_val_to_name[c->role - 1]); - if (!role) { + sym_name(args->oldp, SYM_ROLES, c->role - 1)); + if (!role) goto bad; - } c->role = role->value; /* Convert the type. */ + rc = -EINVAL; typdatum = hashtab_search(args->newp->p_types.table, - args->oldp->p_type_val_to_name[c->type - 1]); - if (!typdatum) { + sym_name(args->oldp, SYM_TYPES, c->type - 1)); + if (!typdatum) goto bad; - } c->type = typdatum->value; - rc = mls_convert_context(args->oldp, args->newp, c); - if (rc) - goto bad; + /* Convert the MLS fields if dealing with MLS policies */ + if (args->oldp->mls_enabled && args->newp->mls_enabled) { + rc = mls_convert_context(args->oldp, args->newp, c); + if (rc) + goto bad; + } else if (args->oldp->mls_enabled && !args->newp->mls_enabled) { + /* + * Switching between MLS and non-MLS policy: + * free any storage used by the MLS fields in the + * context for all existing entries in the sidtab. + */ + mls_context_destroy(c); + } else if (!args->oldp->mls_enabled && args->newp->mls_enabled) { + /* + * Switching between non-MLS and MLS policy: + * ensure that the MLS fields of the context for all + * existing entries in the sidtab are filled in with a + * suitable default value, likely taken from one of the + * initial SIDs. + */ + oc = args->newp->ocontexts[OCON_ISID]; + while (oc && oc->sid[0] != SECINITSID_UNLABELED) + oc = oc->next; + rc = -EINVAL; + if (!oc) { + printk(KERN_ERR "SELinux: unable to look up" + " the initial SIDs list\n"); + goto bad; + } + range = &oc->context[0].range; + rc = mls_range_set(c, range); + if (rc) + goto bad; + } /* Check the validity of the new context. */ if (!policydb_context_isvalid(args->newp, c)) { @@ -1182,17 +1794,36 @@ static int convert_context(u32 key, } context_destroy(&oldc); + + rc = 0; out: return rc; bad: - context_struct_to_string(&oldc, &s, &len); + /* Map old representation to string and save it. */ + rc = context_struct_to_string(&oldc, &s, &len); + if (rc) + return rc; context_destroy(&oldc); - printk(KERN_ERR "security: invalidating context %s\n", s); - kfree(s); + context_destroy(c); + c->str = s; + c->len = len; + printk(KERN_INFO "SELinux: Context %s became invalid (unmapped).\n", + c->str); + rc = 0; goto out; } -extern void selinux_complete_init(void); +static void security_load_policycaps(void) +{ + selinux_policycap_netpeer = ebitmap_get_bit(&policydb.policycaps, + POLICYDB_CAPABILITY_NETPEER); + selinux_policycap_openperm = ebitmap_get_bit(&policydb.policycaps, + POLICYDB_CAPABILITY_OPENPERM); + selinux_policycap_alwaysnetwork = ebitmap_get_bit(&policydb.policycaps, + POLICYDB_CAPABILITY_ALWAYSNETWORK); +} + +static int security_preserve_bools(struct policydb *p); /** * security_load_policy - Load a security policy configuration. @@ -1206,118 +1837,174 @@ extern void selinux_complete_init(void); */ int security_load_policy(void *data, size_t len) { - struct policydb oldpolicydb, newpolicydb; + struct policydb *oldpolicydb, *newpolicydb; struct sidtab oldsidtab, newsidtab; + struct selinux_mapping *oldmap, *map = NULL; struct convert_context_args args; u32 seqno; + u16 map_size; int rc = 0; struct policy_file file = { data, len }, *fp = &file; - LOAD_LOCK; + oldpolicydb = kzalloc(2 * sizeof(*oldpolicydb), GFP_KERNEL); + if (!oldpolicydb) { + rc = -ENOMEM; + goto out; + } + newpolicydb = oldpolicydb + 1; if (!ss_initialized) { avtab_cache_init(); - if (policydb_read(&policydb, fp)) { - LOAD_UNLOCK; + rc = policydb_read(&policydb, fp); + if (rc) { avtab_cache_destroy(); - return -EINVAL; + goto out; } - if (policydb_load_isids(&policydb, &sidtab)) { - LOAD_UNLOCK; + + policydb.len = len; + rc = selinux_set_mapping(&policydb, secclass_map, + ¤t_mapping, + ¤t_mapping_size); + if (rc) { policydb_destroy(&policydb); avtab_cache_destroy(); - return -EINVAL; + goto out; + } + + rc = policydb_load_isids(&policydb, &sidtab); + if (rc) { + policydb_destroy(&policydb); + avtab_cache_destroy(); + goto out; } - policydb_loaded_version = policydb.policyvers; + + security_load_policycaps(); ss_initialized = 1; seqno = ++latest_granting; - LOAD_UNLOCK; selinux_complete_init(); avc_ss_reset(seqno); selnl_notify_policyload(seqno); - return 0; + selinux_status_update_policyload(seqno); + selinux_netlbl_cache_invalidate(); + selinux_xfrm_notify_policyload(); + goto out; } #if 0 sidtab_hash_eval(&sidtab, "sids"); #endif - if (policydb_read(&newpolicydb, fp)) { - LOAD_UNLOCK; - return -EINVAL; + rc = policydb_read(newpolicydb, fp); + if (rc) + goto out; + + newpolicydb->len = len; + /* If switching between different policy types, log MLS status */ + if (policydb.mls_enabled && !newpolicydb->mls_enabled) + printk(KERN_INFO "SELinux: Disabling MLS support...\n"); + else if (!policydb.mls_enabled && newpolicydb->mls_enabled) + printk(KERN_INFO "SELinux: Enabling MLS support...\n"); + + rc = policydb_load_isids(newpolicydb, &newsidtab); + if (rc) { + printk(KERN_ERR "SELinux: unable to load the initial SIDs\n"); + policydb_destroy(newpolicydb); + goto out; } - sidtab_init(&newsidtab); + rc = selinux_set_mapping(newpolicydb, secclass_map, &map, &map_size); + if (rc) + goto err; - /* Verify that the existing classes did not change. */ - if (hashtab_map(policydb.p_classes.table, validate_class, &newpolicydb)) { - printk(KERN_ERR "security: the definition of an existing " - "class changed\n"); - rc = -EINVAL; + rc = security_preserve_bools(newpolicydb); + if (rc) { + printk(KERN_ERR "SELinux: unable to preserve booleans\n"); goto err; } /* Clone the SID table. */ sidtab_shutdown(&sidtab); - if (sidtab_map(&sidtab, clone_sid, &newsidtab)) { - rc = -ENOMEM; + + rc = sidtab_map(&sidtab, clone_sid, &newsidtab); + if (rc) goto err; - } - /* Convert the internal representations of contexts - in the new SID table and remove invalid SIDs. */ + /* + * Convert the internal representations of contexts + * in the new SID table. + */ args.oldp = &policydb; - args.newp = &newpolicydb; - sidtab_map_remove_on_error(&newsidtab, convert_context, &args); + args.newp = newpolicydb; + rc = sidtab_map(&newsidtab, convert_context, &args); + if (rc) { + printk(KERN_ERR "SELinux: unable to convert the internal" + " representation of contexts in the new SID" + " table\n"); + goto err; + } /* Save the old policydb and SID table to free later. */ - memcpy(&oldpolicydb, &policydb, sizeof policydb); + memcpy(oldpolicydb, &policydb, sizeof(policydb)); sidtab_set(&oldsidtab, &sidtab); /* Install the new policydb and SID table. */ - POLICY_WRLOCK; - memcpy(&policydb, &newpolicydb, sizeof policydb); + write_lock_irq(&policy_rwlock); + memcpy(&policydb, newpolicydb, sizeof(policydb)); sidtab_set(&sidtab, &newsidtab); + security_load_policycaps(); + oldmap = current_mapping; + current_mapping = map; + current_mapping_size = map_size; seqno = ++latest_granting; - policydb_loaded_version = policydb.policyvers; - POLICY_WRUNLOCK; - LOAD_UNLOCK; + write_unlock_irq(&policy_rwlock); /* Free the old policydb and SID table. */ - policydb_destroy(&oldpolicydb); + policydb_destroy(oldpolicydb); sidtab_destroy(&oldsidtab); + kfree(oldmap); avc_ss_reset(seqno); selnl_notify_policyload(seqno); + selinux_status_update_policyload(seqno); + selinux_netlbl_cache_invalidate(); + selinux_xfrm_notify_policyload(); - return 0; + rc = 0; + goto out; err: - LOAD_UNLOCK; + kfree(map); sidtab_destroy(&newsidtab); - policydb_destroy(&newpolicydb); + policydb_destroy(newpolicydb); + +out: + kfree(oldpolicydb); return rc; +} + +size_t security_policydb_len(void) +{ + size_t len; + + read_lock(&policy_rwlock); + len = policydb.len; + read_unlock(&policy_rwlock); + return len; } /** * security_port_sid - Obtain the SID for a port. - * @domain: communication domain aka address family - * @type: socket type * @protocol: protocol number * @port: port number * @out_sid: security identifier */ -int security_port_sid(u16 domain, - u16 type, - u8 protocol, - u16 port, - u32 *out_sid) +int security_port_sid(u8 protocol, u16 port, u32 *out_sid) { struct ocontext *c; int rc = 0; - POLICY_RDLOCK; + read_lock(&policy_rwlock); c = policydb.ocontexts[OCON_PORT]; while (c) { @@ -1342,7 +2029,7 @@ int security_port_sid(u16 domain, } out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); return rc; } @@ -1350,16 +2037,13 @@ out: * security_netif_sid - Obtain the SID for a network interface. * @name: interface name * @if_sid: interface SID - * @msg_sid: default SID for received packets */ -int security_netif_sid(char *name, - u32 *if_sid, - u32 *msg_sid) +int security_netif_sid(char *name, u32 *if_sid) { int rc = 0; struct ocontext *c; - POLICY_RDLOCK; + read_lock(&policy_rwlock); c = policydb.ocontexts[OCON_NETIF]; while (c) { @@ -1382,14 +2066,11 @@ int security_netif_sid(char *name, goto out; } *if_sid = c->sid[0]; - *msg_sid = c->sid[1]; - } else { + } else *if_sid = SECINITSID_NETIF; - *msg_sid = SECINITSID_NETMSG; - } out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); return rc; } @@ -1397,8 +2078,8 @@ static int match_ipv6_addrmask(u32 *input, u32 *addr, u32 *mask) { int i, fail = 0; - for(i = 0; i < 4; i++) - if(addr[i] != (input[i] & mask[i])) { + for (i = 0; i < 4; i++) + if (addr[i] != (input[i] & mask[i])) { fail = 1; break; } @@ -1418,19 +2099,18 @@ int security_node_sid(u16 domain, u32 addrlen, u32 *out_sid) { - int rc = 0; + int rc; struct ocontext *c; - POLICY_RDLOCK; + read_lock(&policy_rwlock); switch (domain) { case AF_INET: { u32 addr; - if (addrlen != sizeof(u32)) { - rc = -EINVAL; + rc = -EINVAL; + if (addrlen != sizeof(u32)) goto out; - } addr = *((u32 *)addrp); @@ -1444,10 +2124,9 @@ int security_node_sid(u16 domain, } case AF_INET6: - if (addrlen != sizeof(u64) * 2) { - rc = -EINVAL; + rc = -EINVAL; + if (addrlen != sizeof(u64) * 2) goto out; - } c = policydb.ocontexts[OCON_NODE6]; while (c) { if (match_ipv6_addrmask(addrp, c->u.node6.addr, @@ -1458,6 +2137,7 @@ int security_node_sid(u16 domain, break; default: + rc = 0; *out_sid = SECINITSID_NODE; goto out; } @@ -1475,8 +2155,9 @@ int security_node_sid(u16 domain, *out_sid = SECINITSID_NODE; } + rc = 0; out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); return rc; } @@ -1497,80 +2178,65 @@ out: */ int security_get_user_sids(u32 fromsid, - char *username, + char *username, u32 **sids, u32 *nel) { struct context *fromcon, usercon; - u32 *mysids, *mysids2, sid; + u32 *mysids = NULL, *mysids2, sid; u32 mynel = 0, maxnel = SIDS_NEL; struct user_datum *user; struct role_datum *role; - struct av_decision avd; struct ebitmap_node *rnode, *tnode; int rc = 0, i, j; - if (!ss_initialized) { - *sids = NULL; - *nel = 0; + *sids = NULL; + *nel = 0; + + if (!ss_initialized) goto out; - } - POLICY_RDLOCK; + read_lock(&policy_rwlock); + context_init(&usercon); + + rc = -EINVAL; fromcon = sidtab_search(&sidtab, fromsid); - if (!fromcon) { - rc = -EINVAL; + if (!fromcon) goto out_unlock; - } + rc = -EINVAL; user = hashtab_search(policydb.p_users.table, username); - if (!user) { - rc = -EINVAL; + if (!user) goto out_unlock; - } + usercon.user = user->value; + rc = -ENOMEM; mysids = kcalloc(maxnel, sizeof(*mysids), GFP_ATOMIC); - if (!mysids) { - rc = -ENOMEM; + if (!mysids) goto out_unlock; - } - ebitmap_for_each_bit(&user->roles, rnode, i) { - if (!ebitmap_node_get_bit(rnode, i)) - continue; + ebitmap_for_each_positive_bit(&user->roles, rnode, i) { role = policydb.role_val_to_struct[i]; - usercon.role = i+1; - ebitmap_for_each_bit(&role->types, tnode, j) { - if (!ebitmap_node_get_bit(tnode, j)) - continue; - usercon.type = j+1; + usercon.role = i + 1; + ebitmap_for_each_positive_bit(&role->types, tnode, j) { + usercon.type = j + 1; if (mls_setup_user_range(fromcon, user, &usercon)) continue; - rc = context_struct_compute_av(fromcon, &usercon, - SECCLASS_PROCESS, - PROCESS__TRANSITION, - &avd); - if (rc || !(avd.allowed & PROCESS__TRANSITION)) - continue; rc = sidtab_context_to_sid(&sidtab, &usercon, &sid); - if (rc) { - kfree(mysids); + if (rc) goto out_unlock; - } if (mynel < maxnel) { mysids[mynel++] = sid; } else { + rc = -ENOMEM; maxnel += SIDS_NEL; mysids2 = kcalloc(maxnel, sizeof(*mysids2), GFP_ATOMIC); - if (!mysids2) { - rc = -ENOMEM; - kfree(mysids); + if (!mysids2) goto out_unlock; - } memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); kfree(mysids); mysids = mysids2; @@ -1578,12 +2244,34 @@ int security_get_user_sids(u32 fromsid, } } } - - *sids = mysids; - *nel = mynel; - + rc = 0; out_unlock: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); + if (rc || !mynel) { + kfree(mysids); + goto out; + } + + rc = -ENOMEM; + mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); + if (!mysids2) { + kfree(mysids); + goto out; + } + for (i = 0, j = 0; i < mynel; i++) { + struct av_decision dummy_avd; + rc = avc_has_perm_noaudit(fromsid, mysids[i], + SECCLASS_PROCESS, /* kernel value */ + PROCESS__TRANSITION, AVC_STRICT, + &dummy_avd); + if (!rc) + mysids2[j++] = mysids[i]; + cond_resched(); + } + rc = 0; + kfree(mysids); + *sids = mysids2; + *nel = j; out: return rc; } @@ -1600,16 +2288,23 @@ out: * transition SIDs or task SIDs. */ int security_genfs_sid(const char *fstype, - char *path, - u16 sclass, + char *path, + u16 orig_sclass, u32 *sid) { int len; + u16 sclass; struct genfs *genfs; struct ocontext *c; - int rc = 0, cmp = 0; + int rc, cmp = 0; + + while (path[0] == '/' && path[1] == '/') + path++; - POLICY_RDLOCK; + read_lock(&policy_rwlock); + + sclass = unmap_class(orig_sclass); + *sid = SECINITSID_UNLABELED; for (genfs = policydb.genfs; genfs; genfs = genfs->next) { cmp = strcmp(fstype, genfs->fstype); @@ -1617,11 +2312,9 @@ int security_genfs_sid(const char *fstype, break; } - if (!genfs || cmp) { - *sid = SECINITSID_UNLABELED; - rc = -ENOENT; + rc = -ENOENT; + if (!genfs || cmp) goto out; - } for (c = genfs->head; c; c = c->next) { len = strlen(c->u.name); @@ -1630,41 +2323,35 @@ int security_genfs_sid(const char *fstype, break; } - if (!c) { - *sid = SECINITSID_UNLABELED; - rc = -ENOENT; + rc = -ENOENT; + if (!c) goto out; - } if (!c->sid[0]) { - rc = sidtab_context_to_sid(&sidtab, - &c->context[0], - &c->sid[0]); + rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]); if (rc) goto out; } *sid = c->sid[0]; + rc = 0; out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); return rc; } /** * security_fs_use - Determine how to handle labeling for a filesystem. - * @fstype: filesystem type - * @behavior: labeling behavior - * @sid: SID for filesystem (superblock) + * @sb: superblock in question */ -int security_fs_use( - const char *fstype, - unsigned int *behavior, - u32 *sid) +int security_fs_use(struct super_block *sb) { int rc = 0; struct ocontext *c; + struct superblock_security_struct *sbsec = sb->s_security; + const char *fstype = sb->s_type->name; - POLICY_RDLOCK; + read_lock(&policy_rwlock); c = policydb.ocontexts[OCON_FSUSE]; while (c) { @@ -1674,65 +2361,69 @@ int security_fs_use( } if (c) { - *behavior = c->v.behavior; + sbsec->behavior = c->v.behavior; if (!c->sid[0]) { - rc = sidtab_context_to_sid(&sidtab, - &c->context[0], + rc = sidtab_context_to_sid(&sidtab, &c->context[0], &c->sid[0]); if (rc) goto out; } - *sid = c->sid[0]; + sbsec->sid = c->sid[0]; } else { - rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, sid); + rc = security_genfs_sid(fstype, "/", SECCLASS_DIR, &sbsec->sid); if (rc) { - *behavior = SECURITY_FS_USE_NONE; + sbsec->behavior = SECURITY_FS_USE_NONE; rc = 0; } else { - *behavior = SECURITY_FS_USE_GENFS; + sbsec->behavior = SECURITY_FS_USE_GENFS; } } out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); return rc; } int security_get_bools(int *len, char ***names, int **values) { - int i, rc = -ENOMEM; + int i, rc; - POLICY_RDLOCK; + read_lock(&policy_rwlock); *names = NULL; *values = NULL; + rc = 0; *len = policydb.p_bools.nprim; - if (!*len) { - rc = 0; + if (!*len) goto out; - } - *names = (char**)kcalloc(*len, sizeof(char*), GFP_ATOMIC); + rc = -ENOMEM; + *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); if (!*names) goto err; - *values = (int*)kcalloc(*len, sizeof(int), GFP_ATOMIC); + rc = -ENOMEM; + *values = kcalloc(*len, sizeof(int), GFP_ATOMIC); if (!*values) goto err; for (i = 0; i < *len; i++) { size_t name_len; + (*values)[i] = policydb.bool_val_to_struct[i]->state; - name_len = strlen(policydb.p_bool_val_to_name[i]) + 1; - (*names)[i] = (char*)kmalloc(sizeof(char) * name_len, GFP_ATOMIC); + name_len = strlen(sym_name(&policydb, SYM_BOOLS, i)) + 1; + + rc = -ENOMEM; + (*names)[i] = kmalloc(sizeof(char) * name_len, GFP_ATOMIC); if (!(*names)[i]) goto err; - strncpy((*names)[i], policydb.p_bool_val_to_name[i], name_len); + + strncpy((*names)[i], sym_name(&policydb, SYM_BOOLS, i), name_len); (*names)[i][name_len - 1] = 0; } rc = 0; out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); return rc; err: if (*names) { @@ -1746,64 +2437,826 @@ err: int security_set_bools(int len, int *values) { - int i, rc = 0; + int i, rc; int lenp, seqno = 0; struct cond_node *cur; - POLICY_WRLOCK; + write_lock_irq(&policy_rwlock); + rc = -EFAULT; lenp = policydb.p_bools.nprim; - if (len != lenp) { - rc = -EFAULT; + if (len != lenp) goto out; - } - printk(KERN_INFO "security: committed booleans { "); for (i = 0; i < len; i++) { - if (values[i]) { + if (!!values[i] != policydb.bool_val_to_struct[i]->state) { + audit_log(current->audit_context, GFP_ATOMIC, + AUDIT_MAC_CONFIG_CHANGE, + "bool=%s val=%d old_val=%d auid=%u ses=%u", + sym_name(&policydb, SYM_BOOLS, i), + !!values[i], + policydb.bool_val_to_struct[i]->state, + from_kuid(&init_user_ns, audit_get_loginuid(current)), + audit_get_sessionid(current)); + } + if (values[i]) policydb.bool_val_to_struct[i]->state = 1; - } else { + else policydb.bool_val_to_struct[i]->state = 0; - } - if (i != 0) - printk(", "); - printk("%s:%d", policydb.p_bool_val_to_name[i], - policydb.bool_val_to_struct[i]->state); } - printk(" }\n"); - for (cur = policydb.cond_list; cur != NULL; cur = cur->next) { + for (cur = policydb.cond_list; cur; cur = cur->next) { rc = evaluate_cond_node(&policydb, cur); if (rc) goto out; } seqno = ++latest_granting; - + rc = 0; out: - POLICY_WRUNLOCK; + write_unlock_irq(&policy_rwlock); if (!rc) { avc_ss_reset(seqno); selnl_notify_policyload(seqno); + selinux_status_update_policyload(seqno); + selinux_xfrm_notify_policyload(); } return rc; } int security_get_bool_value(int bool) { - int rc = 0; + int rc; int len; - POLICY_RDLOCK; + read_lock(&policy_rwlock); + rc = -EFAULT; len = policydb.p_bools.nprim; - if (bool >= len) { - rc = -EFAULT; + if (bool >= len) goto out; - } rc = policydb.bool_val_to_struct[bool]->state; out: - POLICY_RDUNLOCK; + read_unlock(&policy_rwlock); + return rc; +} + +static int security_preserve_bools(struct policydb *p) +{ + int rc, nbools = 0, *bvalues = NULL, i; + char **bnames = NULL; + struct cond_bool_datum *booldatum; + struct cond_node *cur; + + rc = security_get_bools(&nbools, &bnames, &bvalues); + if (rc) + goto out; + for (i = 0; i < nbools; i++) { + booldatum = hashtab_search(p->p_bools.table, bnames[i]); + if (booldatum) + booldatum->state = bvalues[i]; + } + for (cur = p->cond_list; cur; cur = cur->next) { + rc = evaluate_cond_node(p, cur); + if (rc) + goto out; + } + +out: + if (bnames) { + for (i = 0; i < nbools; i++) + kfree(bnames[i]); + } + kfree(bnames); + kfree(bvalues); + return rc; +} + +/* + * security_sid_mls_copy() - computes a new sid based on the given + * sid and the mls portion of mls_sid. + */ +int security_sid_mls_copy(u32 sid, u32 mls_sid, u32 *new_sid) +{ + struct context *context1; + struct context *context2; + struct context newcon; + char *s; + u32 len; + int rc; + + rc = 0; + if (!ss_initialized || !policydb.mls_enabled) { + *new_sid = sid; + goto out; + } + + context_init(&newcon); + + read_lock(&policy_rwlock); + + rc = -EINVAL; + context1 = sidtab_search(&sidtab, sid); + if (!context1) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, sid); + goto out_unlock; + } + + rc = -EINVAL; + context2 = sidtab_search(&sidtab, mls_sid); + if (!context2) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, mls_sid); + goto out_unlock; + } + + newcon.user = context1->user; + newcon.role = context1->role; + newcon.type = context1->type; + rc = mls_context_cpy(&newcon, context2); + if (rc) + goto out_unlock; + + /* Check the validity of the new context. */ + if (!policydb_context_isvalid(&policydb, &newcon)) { + rc = convert_context_handle_invalid_context(&newcon); + if (rc) { + if (!context_struct_to_string(&newcon, &s, &len)) { + audit_log(current->audit_context, GFP_ATOMIC, AUDIT_SELINUX_ERR, + "security_sid_mls_copy: invalid context %s", s); + kfree(s); + } + goto out_unlock; + } + } + + rc = sidtab_context_to_sid(&sidtab, &newcon, new_sid); +out_unlock: + read_unlock(&policy_rwlock); + context_destroy(&newcon); +out: + return rc; +} + +/** + * security_net_peersid_resolve - Compare and resolve two network peer SIDs + * @nlbl_sid: NetLabel SID + * @nlbl_type: NetLabel labeling protocol type + * @xfrm_sid: XFRM SID + * + * Description: + * Compare the @nlbl_sid and @xfrm_sid values and if the two SIDs can be + * resolved into a single SID it is returned via @peer_sid and the function + * returns zero. Otherwise @peer_sid is set to SECSID_NULL and the function + * returns a negative value. A table summarizing the behavior is below: + * + * | function return | @sid + * ------------------------------+-----------------+----------------- + * no peer labels | 0 | SECSID_NULL + * single peer label | 0 | <peer_label> + * multiple, consistent labels | 0 | <peer_label> + * multiple, inconsistent labels | -<errno> | SECSID_NULL + * + */ +int security_net_peersid_resolve(u32 nlbl_sid, u32 nlbl_type, + u32 xfrm_sid, + u32 *peer_sid) +{ + int rc; + struct context *nlbl_ctx; + struct context *xfrm_ctx; + + *peer_sid = SECSID_NULL; + + /* handle the common (which also happens to be the set of easy) cases + * right away, these two if statements catch everything involving a + * single or absent peer SID/label */ + if (xfrm_sid == SECSID_NULL) { + *peer_sid = nlbl_sid; + return 0; + } + /* NOTE: an nlbl_type == NETLBL_NLTYPE_UNLABELED is a "fallback" label + * and is treated as if nlbl_sid == SECSID_NULL when a XFRM SID/label + * is present */ + if (nlbl_sid == SECSID_NULL || nlbl_type == NETLBL_NLTYPE_UNLABELED) { + *peer_sid = xfrm_sid; + return 0; + } + + /* we don't need to check ss_initialized here since the only way both + * nlbl_sid and xfrm_sid are not equal to SECSID_NULL would be if the + * security server was initialized and ss_initialized was true */ + if (!policydb.mls_enabled) + return 0; + + read_lock(&policy_rwlock); + + rc = -EINVAL; + nlbl_ctx = sidtab_search(&sidtab, nlbl_sid); + if (!nlbl_ctx) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, nlbl_sid); + goto out; + } + rc = -EINVAL; + xfrm_ctx = sidtab_search(&sidtab, xfrm_sid); + if (!xfrm_ctx) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, xfrm_sid); + goto out; + } + rc = (mls_context_cmp(nlbl_ctx, xfrm_ctx) ? 0 : -EACCES); + if (rc) + goto out; + + /* at present NetLabel SIDs/labels really only carry MLS + * information so if the MLS portion of the NetLabel SID + * matches the MLS portion of the labeled XFRM SID/label + * then pass along the XFRM SID as it is the most + * expressive */ + *peer_sid = xfrm_sid; +out: + read_unlock(&policy_rwlock); + return rc; +} + +static int get_classes_callback(void *k, void *d, void *args) +{ + struct class_datum *datum = d; + char *name = k, **classes = args; + int value = datum->value - 1; + + classes[value] = kstrdup(name, GFP_ATOMIC); + if (!classes[value]) + return -ENOMEM; + + return 0; +} + +int security_get_classes(char ***classes, int *nclasses) +{ + int rc; + + read_lock(&policy_rwlock); + + rc = -ENOMEM; + *nclasses = policydb.p_classes.nprim; + *classes = kcalloc(*nclasses, sizeof(**classes), GFP_ATOMIC); + if (!*classes) + goto out; + + rc = hashtab_map(policydb.p_classes.table, get_classes_callback, + *classes); + if (rc) { + int i; + for (i = 0; i < *nclasses; i++) + kfree((*classes)[i]); + kfree(*classes); + } + +out: + read_unlock(&policy_rwlock); return rc; } + +static int get_permissions_callback(void *k, void *d, void *args) +{ + struct perm_datum *datum = d; + char *name = k, **perms = args; + int value = datum->value - 1; + + perms[value] = kstrdup(name, GFP_ATOMIC); + if (!perms[value]) + return -ENOMEM; + + return 0; +} + +int security_get_permissions(char *class, char ***perms, int *nperms) +{ + int rc, i; + struct class_datum *match; + + read_lock(&policy_rwlock); + + rc = -EINVAL; + match = hashtab_search(policydb.p_classes.table, class); + if (!match) { + printk(KERN_ERR "SELinux: %s: unrecognized class %s\n", + __func__, class); + goto out; + } + + rc = -ENOMEM; + *nperms = match->permissions.nprim; + *perms = kcalloc(*nperms, sizeof(**perms), GFP_ATOMIC); + if (!*perms) + goto out; + + if (match->comdatum) { + rc = hashtab_map(match->comdatum->permissions.table, + get_permissions_callback, *perms); + if (rc) + goto err; + } + + rc = hashtab_map(match->permissions.table, get_permissions_callback, + *perms); + if (rc) + goto err; + +out: + read_unlock(&policy_rwlock); + return rc; + +err: + read_unlock(&policy_rwlock); + for (i = 0; i < *nperms; i++) + kfree((*perms)[i]); + kfree(*perms); + return rc; +} + +int security_get_reject_unknown(void) +{ + return policydb.reject_unknown; +} + +int security_get_allow_unknown(void) +{ + return policydb.allow_unknown; +} + +/** + * security_policycap_supported - Check for a specific policy capability + * @req_cap: capability + * + * Description: + * This function queries the currently loaded policy to see if it supports the + * capability specified by @req_cap. Returns true (1) if the capability is + * supported, false (0) if it isn't supported. + * + */ +int security_policycap_supported(unsigned int req_cap) +{ + int rc; + + read_lock(&policy_rwlock); + rc = ebitmap_get_bit(&policydb.policycaps, req_cap); + read_unlock(&policy_rwlock); + + return rc; +} + +struct selinux_audit_rule { + u32 au_seqno; + struct context au_ctxt; +}; + +void selinux_audit_rule_free(void *vrule) +{ + struct selinux_audit_rule *rule = vrule; + + if (rule) { + context_destroy(&rule->au_ctxt); + kfree(rule); + } +} + +int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) +{ + struct selinux_audit_rule *tmprule; + struct role_datum *roledatum; + struct type_datum *typedatum; + struct user_datum *userdatum; + struct selinux_audit_rule **rule = (struct selinux_audit_rule **)vrule; + int rc = 0; + + *rule = NULL; + + if (!ss_initialized) + return -EOPNOTSUPP; + + switch (field) { + case AUDIT_SUBJ_USER: + case AUDIT_SUBJ_ROLE: + case AUDIT_SUBJ_TYPE: + case AUDIT_OBJ_USER: + case AUDIT_OBJ_ROLE: + case AUDIT_OBJ_TYPE: + /* only 'equals' and 'not equals' fit user, role, and type */ + if (op != Audit_equal && op != Audit_not_equal) + return -EINVAL; + break; + case AUDIT_SUBJ_SEN: + case AUDIT_SUBJ_CLR: + case AUDIT_OBJ_LEV_LOW: + case AUDIT_OBJ_LEV_HIGH: + /* we do not allow a range, indicated by the presence 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); + + read_lock(&policy_rwlock); + + tmprule->au_seqno = latest_granting; + + switch (field) { + case AUDIT_SUBJ_USER: + case AUDIT_OBJ_USER: + rc = -EINVAL; + userdatum = hashtab_search(policydb.p_users.table, rulestr); + if (!userdatum) + goto out; + tmprule->au_ctxt.user = userdatum->value; + break; + case AUDIT_SUBJ_ROLE: + case AUDIT_OBJ_ROLE: + rc = -EINVAL; + roledatum = hashtab_search(policydb.p_roles.table, rulestr); + if (!roledatum) + goto out; + tmprule->au_ctxt.role = roledatum->value; + break; + case AUDIT_SUBJ_TYPE: + case AUDIT_OBJ_TYPE: + rc = -EINVAL; + typedatum = hashtab_search(policydb.p_types.table, rulestr); + if (!typedatum) + goto out; + tmprule->au_ctxt.type = typedatum->value; + break; + case AUDIT_SUBJ_SEN: + case AUDIT_SUBJ_CLR: + case AUDIT_OBJ_LEV_LOW: + case AUDIT_OBJ_LEV_HIGH: + rc = mls_from_string(rulestr, &tmprule->au_ctxt, GFP_ATOMIC); + if (rc) + goto out; + break; + } + rc = 0; +out: + read_unlock(&policy_rwlock); + + if (rc) { + selinux_audit_rule_free(tmprule); + tmprule = NULL; + } + + *rule = tmprule; + + return rc; +} + +/* Check to see if the rule contains any selinux fields */ +int selinux_audit_rule_known(struct audit_krule *rule) +{ + int i; + + for (i = 0; i < rule->field_count; i++) { + struct audit_field *f = &rule->fields[i]; + switch (f->type) { + case AUDIT_SUBJ_USER: + case AUDIT_SUBJ_ROLE: + case AUDIT_SUBJ_TYPE: + case AUDIT_SUBJ_SEN: + case AUDIT_SUBJ_CLR: + case AUDIT_OBJ_USER: + case AUDIT_OBJ_ROLE: + case AUDIT_OBJ_TYPE: + case AUDIT_OBJ_LEV_LOW: + case AUDIT_OBJ_LEV_HIGH: + return 1; + } + } + + return 0; +} + +int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule, + struct audit_context *actx) +{ + struct context *ctxt; + struct mls_level *level; + struct selinux_audit_rule *rule = vrule; + int match = 0; + + if (unlikely(!rule)) { + WARN_ONCE(1, "selinux_audit_rule_match: missing rule\n"); + return -ENOENT; + } + + read_lock(&policy_rwlock); + + if (rule->au_seqno < latest_granting) { + match = -ESTALE; + goto out; + } + + ctxt = sidtab_search(&sidtab, sid); + if (unlikely(!ctxt)) { + WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n", + sid); + match = -ENOENT; + goto out; + } + + /* a field/op pair that is not caught here will simply fall through + without a match */ + switch (field) { + case AUDIT_SUBJ_USER: + case AUDIT_OBJ_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_SUBJ_ROLE: + case AUDIT_OBJ_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_SUBJ_TYPE: + case AUDIT_OBJ_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_SUBJ_SEN: + case AUDIT_SUBJ_CLR: + case AUDIT_OBJ_LEV_LOW: + case AUDIT_OBJ_LEV_HIGH: + level = ((field == AUDIT_SUBJ_SEN || + field == AUDIT_OBJ_LEV_LOW) ? + &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_lt: + match = (mls_level_dom(&rule->au_ctxt.range.level[0], + level) && + !mls_level_eq(&rule->au_ctxt.range.level[0], + level)); + break; + case Audit_le: + match = mls_level_dom(&rule->au_ctxt.range.level[0], + level); + break; + case Audit_gt: + match = (mls_level_dom(level, + &rule->au_ctxt.range.level[0]) && + !mls_level_eq(level, + &rule->au_ctxt.range.level[0])); + break; + case Audit_ge: + match = mls_level_dom(level, + &rule->au_ctxt.range.level[0]); + break; + } + } + +out: + read_unlock(&policy_rwlock); + return match; +} + +static int (*aurule_callback)(void) = audit_update_lsm_rules; + +static int aurule_avc_callback(u32 event) +{ + 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); + if (err) + panic("avc_add_callback() failed, error %d\n", err); + + return err; +} +__initcall(aurule_init); + +#ifdef CONFIG_NETLABEL +/** + * security_netlbl_cache_add - Add an entry to the NetLabel cache + * @secattr: the NetLabel packet security attributes + * @sid: the SELinux SID + * + * Description: + * Attempt to cache the context in @ctx, which was derived from the packet in + * @skb, in the NetLabel subsystem cache. This function assumes @secattr has + * already been initialized. + * + */ +static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, + u32 sid) +{ + u32 *sid_cache; + + sid_cache = kmalloc(sizeof(*sid_cache), GFP_ATOMIC); + if (sid_cache == NULL) + return; + secattr->cache = netlbl_secattr_cache_alloc(GFP_ATOMIC); + if (secattr->cache == NULL) { + kfree(sid_cache); + return; + } + + *sid_cache = sid; + secattr->cache->free = kfree; + secattr->cache->data = sid_cache; + secattr->flags |= NETLBL_SECATTR_CACHE; +} + +/** + * security_netlbl_secattr_to_sid - Convert a NetLabel secattr to a SELinux SID + * @secattr: the NetLabel packet security attributes + * @sid: the SELinux SID + * + * Description: + * Convert the given NetLabel security attributes in @secattr into a + * SELinux SID. If the @secattr field does not contain a full SELinux + * SID/context then use SECINITSID_NETMSG as the foundation. If possible the + * 'cache' field of @secattr is set and the CACHE flag is set; this is to + * allow the @secattr to be used by NetLabel to cache the secattr to SID + * conversion for future lookups. Returns zero on success, negative values on + * failure. + * + */ +int security_netlbl_secattr_to_sid(struct netlbl_lsm_secattr *secattr, + u32 *sid) +{ + int rc; + struct context *ctx; + struct context ctx_new; + + if (!ss_initialized) { + *sid = SECSID_NULL; + return 0; + } + + read_lock(&policy_rwlock); + + if (secattr->flags & NETLBL_SECATTR_CACHE) + *sid = *(u32 *)secattr->cache->data; + else if (secattr->flags & NETLBL_SECATTR_SECID) + *sid = secattr->attr.secid; + else if (secattr->flags & NETLBL_SECATTR_MLS_LVL) { + rc = -EIDRM; + ctx = sidtab_search(&sidtab, SECINITSID_NETMSG); + if (ctx == NULL) + goto out; + + context_init(&ctx_new); + ctx_new.user = ctx->user; + ctx_new.role = ctx->role; + ctx_new.type = ctx->type; + mls_import_netlbl_lvl(&ctx_new, secattr); + if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { + rc = ebitmap_netlbl_import(&ctx_new.range.level[0].cat, + secattr->attr.mls.cat); + if (rc) + goto out; + memcpy(&ctx_new.range.level[1].cat, + &ctx_new.range.level[0].cat, + sizeof(ctx_new.range.level[0].cat)); + } + rc = -EIDRM; + if (!mls_context_isvalid(&policydb, &ctx_new)) + goto out_free; + + rc = sidtab_context_to_sid(&sidtab, &ctx_new, sid); + if (rc) + goto out_free; + + security_netlbl_cache_add(secattr, *sid); + + ebitmap_destroy(&ctx_new.range.level[0].cat); + } else + *sid = SECSID_NULL; + + read_unlock(&policy_rwlock); + return 0; +out_free: + ebitmap_destroy(&ctx_new.range.level[0].cat); +out: + read_unlock(&policy_rwlock); + return rc; +} + +/** + * security_netlbl_sid_to_secattr - Convert a SELinux SID to a NetLabel secattr + * @sid: the SELinux SID + * @secattr: the NetLabel packet security attributes + * + * Description: + * Convert the given SELinux SID in @sid into a NetLabel security attribute. + * Returns zero on success, negative values on failure. + * + */ +int security_netlbl_sid_to_secattr(u32 sid, struct netlbl_lsm_secattr *secattr) +{ + int rc; + struct context *ctx; + + if (!ss_initialized) + return 0; + + read_lock(&policy_rwlock); + + rc = -ENOENT; + ctx = sidtab_search(&sidtab, sid); + if (ctx == NULL) + goto out; + + rc = -ENOMEM; + secattr->domain = kstrdup(sym_name(&policydb, SYM_TYPES, ctx->type - 1), + GFP_ATOMIC); + if (secattr->domain == NULL) + goto out; + + secattr->attr.secid = sid; + secattr->flags |= NETLBL_SECATTR_DOMAIN_CPY | NETLBL_SECATTR_SECID; + mls_export_netlbl_lvl(ctx, secattr); + rc = mls_export_netlbl_cat(ctx, secattr); +out: + read_unlock(&policy_rwlock); + return rc; +} +#endif /* CONFIG_NETLABEL */ + +/** + * security_read_policy - read the policy. + * @data: binary policy data + * @len: length of data in bytes + * + */ +int security_read_policy(void **data, size_t *len) +{ + int rc; + struct policy_file fp; + + if (!ss_initialized) + return -EINVAL; + + *len = security_policydb_len(); + + *data = vmalloc_user(*len); + if (!*data) + return -ENOMEM; + + fp.data = *data; + fp.len = *len; + + read_lock(&policy_rwlock); + rc = policydb_write(&policydb, &fp); + read_unlock(&policy_rwlock); + + if (rc) + return rc; + + *len = (unsigned long)fp.data - (unsigned long)*data; + return 0; + +} |