diff options
Diffstat (limited to 'security/selinux/ss/services.c')
| -rw-r--r-- | security/selinux/ss/services.c | 273 |
1 files changed, 176 insertions, 97 deletions
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index a03cfaf0ee0..4bca49414a4 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -13,7 +13,7 @@ * * Added conditional policy language extensions * - * Updated: Hewlett-Packard <paul.moore@hp.com> + * Updated: Hewlett-Packard <paul@paul-moore.com> * * Added support for NetLabel * Added support for the policy capability bitmap @@ -70,10 +70,9 @@ #include "ebitmap.h" #include "audit.h" -extern void selnl_notify_policyload(u32 seqno); - int selinux_policycap_netpeer; int selinux_policycap_openperm; +int selinux_policycap_alwaysnetwork; static DEFINE_RWLOCK(policy_rwlock); @@ -201,6 +200,21 @@ static u16 unmap_class(u16 tclass) 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) { @@ -1005,9 +1019,11 @@ static int context_struct_to_string(struct context *context, char **scontext, u3 if (context->len) { *scontext_len = context->len; - *scontext = kstrdup(context->str, GFP_ATOMIC); - if (!(*scontext)) - return -ENOMEM; + if (scontext) { + *scontext = kstrdup(context->str, GFP_ATOMIC); + if (!(*scontext)) + return -ENOMEM; + } return 0; } @@ -1216,6 +1232,10 @@ static int security_context_to_sid_core(const char *scontext, u32 scontext_len, struct context context; int rc = 0; + /* An empty security context is never valid. */ + if (!scontext_len) + return -EINVAL; + if (!ss_initialized) { int i; @@ -1269,16 +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(const 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, GFP_KERNEL, 0); + sid, SECSID_NULL, gfp, 0); } /** @@ -1343,13 +1365,40 @@ 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 orig_tclass, u32 specified, + 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; @@ -1357,6 +1406,7 @@ static int security_compute_sid(u32 ssid, struct avtab_node *node; u16 tclass; int rc = 0; + bool sock; if (!ss_initialized) { switch (orig_tclass) { @@ -1374,10 +1424,13 @@ static int security_compute_sid(u32 ssid, read_lock(&policy_rwlock); - if (kern) + if (kern) { tclass = unmap_class(orig_tclass); - else + 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) { @@ -1394,12 +1447,20 @@ static int security_compute_sid(u32 ssid, goto out_unlock; } + 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. */ @@ -1407,16 +1468,31 @@ static int security_compute_sid(u32 ssid, break; } - /* Set the role and type to default values. */ - if (tclass == policydb.process_class) { - /* 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; - newcontext.type = scontext->type; + } else if (cladatum && cladatum->default_role == DEFAULT_TARGET) { + newcontext.role = tcontext->role; } else { - /* Use the well-defined object role. */ - newcontext.role = OBJECT_R_VAL; - /* Use the type of the related object. */ + 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; + } 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. */ @@ -1442,25 +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. */ - if (tclass == policydb.process_class) { - 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; } } } /* 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; @@ -1495,22 +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, - out_sid, true); + qstr ? qstr->name : NULL, out_sid, true); } -int security_transition_sid_user(u32 ssid, - u32 tsid, - u16 tclass, - u32 *out_sid) +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, false); + objname, out_sid, false); } /** @@ -1531,8 +1607,8 @@ int security_member_sid(u32 ssid, u16 tclass, u32 *out_sid) { - return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, out_sid, - false); + return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL, + out_sid, false); } /** @@ -1553,8 +1629,8 @@ int security_change_sid(u32 ssid, u16 tclass, u32 *out_sid) { - return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, out_sid, - false); + return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL, + out_sid, false); } /* Clone the SID into the new SID table. */ @@ -1743,9 +1819,10 @@ static void security_load_policycaps(void) 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); } -extern void selinux_complete_init(void); static int security_preserve_bools(struct policydb *p); /** @@ -1760,7 +1837,7 @@ static int security_preserve_bools(struct policydb *p); */ 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; @@ -1769,12 +1846,19 @@ int security_load_policy(void *data, size_t len) int rc = 0; struct policy_file file = { data, len }, *fp = &file; + oldpolicydb = kzalloc(2 * sizeof(*oldpolicydb), GFP_KERNEL); + if (!oldpolicydb) { + rc = -ENOMEM; + goto out; + } + newpolicydb = oldpolicydb + 1; + if (!ss_initialized) { avtab_cache_init(); rc = policydb_read(&policydb, fp); if (rc) { avtab_cache_destroy(); - return rc; + goto out; } policydb.len = len; @@ -1784,14 +1868,14 @@ int security_load_policy(void *data, size_t len) if (rc) { policydb_destroy(&policydb); avtab_cache_destroy(); - return rc; + goto out; } rc = policydb_load_isids(&policydb, &sidtab); if (rc) { policydb_destroy(&policydb); avtab_cache_destroy(); - return rc; + goto out; } security_load_policycaps(); @@ -1803,36 +1887,36 @@ int security_load_policy(void *data, size_t len) selinux_status_update_policyload(seqno); selinux_netlbl_cache_invalidate(); selinux_xfrm_notify_policyload(); - return 0; + goto out; } #if 0 sidtab_hash_eval(&sidtab, "sids"); #endif - rc = policydb_read(&newpolicydb, fp); + rc = policydb_read(newpolicydb, fp); if (rc) - return rc; + goto out; - newpolicydb.len = len; + newpolicydb->len = len; /* If switching between different policy types, log MLS status */ - if (policydb.mls_enabled && !newpolicydb.mls_enabled) + if (policydb.mls_enabled && !newpolicydb->mls_enabled) printk(KERN_INFO "SELinux: Disabling MLS support...\n"); - else if (!policydb.mls_enabled && newpolicydb.mls_enabled) + else if (!policydb.mls_enabled && newpolicydb->mls_enabled) printk(KERN_INFO "SELinux: Enabling MLS support...\n"); - rc = policydb_load_isids(&newpolicydb, &newsidtab); + rc = policydb_load_isids(newpolicydb, &newsidtab); if (rc) { printk(KERN_ERR "SELinux: unable to load the initial SIDs\n"); - policydb_destroy(&newpolicydb); - return rc; + policydb_destroy(newpolicydb); + goto out; } - rc = selinux_set_mapping(&newpolicydb, secclass_map, &map, &map_size); + rc = selinux_set_mapping(newpolicydb, secclass_map, &map, &map_size); if (rc) goto err; - rc = security_preserve_bools(&newpolicydb); + rc = security_preserve_bools(newpolicydb); if (rc) { printk(KERN_ERR "SELinux: unable to preserve booleans\n"); goto err; @@ -1850,7 +1934,7 @@ int security_load_policy(void *data, size_t len) * in the new SID table. */ args.oldp = &policydb; - args.newp = &newpolicydb; + args.newp = newpolicydb; rc = sidtab_map(&newsidtab, convert_context, &args); if (rc) { printk(KERN_ERR "SELinux: unable to convert the internal" @@ -1860,12 +1944,12 @@ int security_load_policy(void *data, size_t len) } /* 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. */ write_lock_irq(&policy_rwlock); - memcpy(&policydb, &newpolicydb, sizeof policydb); + memcpy(&policydb, newpolicydb, sizeof(policydb)); sidtab_set(&sidtab, &newsidtab); security_load_policycaps(); oldmap = current_mapping; @@ -1875,7 +1959,7 @@ int security_load_policy(void *data, size_t len) write_unlock_irq(&policy_rwlock); /* Free the old policydb and SID table. */ - policydb_destroy(&oldpolicydb); + policydb_destroy(oldpolicydb); sidtab_destroy(&oldsidtab); kfree(oldmap); @@ -1885,14 +1969,17 @@ int security_load_policy(void *data, size_t len) selinux_netlbl_cache_invalidate(); selinux_xfrm_notify_policyload(); - return 0; + rc = 0; + goto out; err: kfree(map); sidtab_destroy(&newsidtab); - policydb_destroy(&newpolicydb); - return rc; + policydb_destroy(newpolicydb); +out: + kfree(oldpolicydb); + return rc; } size_t security_policydb_len(void) @@ -2172,10 +2259,11 @@ out_unlock: 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, - NULL); + &dummy_avd); if (!rc) mysids2[j++] = mysids[i]; cond_resched(); @@ -2254,17 +2342,14 @@ out: /** * 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; read_lock(&policy_rwlock); @@ -2276,21 +2361,21 @@ 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], &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; } } @@ -2371,7 +2456,7 @@ int security_set_bools(int len, int *values) sym_name(&policydb, SYM_BOOLS, i), !!values[i], policydb.bool_val_to_struct[i]->state, - audit_get_loginuid(current), + from_kuid(&init_user_ns, audit_get_loginuid(current)), audit_get_sessionid(current)); } if (values[i]) @@ -2769,7 +2854,7 @@ int selinux_audit_rule_init(u32 field, u32 op, char *rulestr, void **vrule) case AUDIT_SUBJ_CLR: case AUDIT_OBJ_LEV_LOW: case AUDIT_OBJ_LEV_HIGH: - /* we do not allow a range, indicated by the presense of '-' */ + /* we do not allow a range, indicated by the presence of '-' */ if (strchr(rulestr, '-')) return -EINVAL; break; @@ -2869,25 +2954,21 @@ int selinux_audit_rule_match(u32 sid, u32 field, u32 op, void *vrule, struct selinux_audit_rule *rule = vrule; int match = 0; - if (!rule) { - audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "selinux_audit_rule_match: missing rule\n"); + 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) { - audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "selinux_audit_rule_match: stale rule\n"); match = -ESTALE; goto out; } ctxt = sidtab_search(&sidtab, sid); - if (!ctxt) { - audit_log(actx, GFP_ATOMIC, AUDIT_SELINUX_ERR, - "selinux_audit_rule_match: unrecognized SID %d\n", + if (unlikely(!ctxt)) { + WARN_ONCE(1, "selinux_audit_rule_match: unrecognized SID %d\n", sid); match = -ENOENT; goto out; @@ -2975,8 +3056,7 @@ out: static int (*aurule_callback)(void) = audit_update_lsm_rules; -static int aurule_avc_callback(u32 event, u32 ssid, u32 tsid, - u16 class, u32 perms, u32 *retained) +static int aurule_avc_callback(u32 event) { int err = 0; @@ -2989,8 +3069,7 @@ 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); + err = avc_add_callback(aurule_avc_callback, AVC_CALLBACK_RESET); if (err) panic("avc_add_callback() failed, error %d\n", err); @@ -3038,7 +3117,7 @@ static void security_netlbl_cache_add(struct netlbl_lsm_secattr *secattr, * 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 possibile the + * 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 @@ -3153,7 +3232,7 @@ out: * @len: length of data in bytes * */ -int security_read_policy(void **data, ssize_t *len) +int security_read_policy(void **data, size_t *len) { int rc; struct policy_file fp; |
