diff options
Diffstat (limited to 'security/selinux/ss/services.c')
| -rw-r--r-- | security/selinux/ss/services.c | 249 |
1 files changed, 220 insertions, 29 deletions
diff --git a/security/selinux/ss/services.c b/security/selinux/ss/services.c index 973e00e..2286306 100644 --- a/security/selinux/ss/services.c +++ b/security/selinux/ss/services.c @@ -94,9 +94,10 @@ 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 context *tcontext, + u16 tclass, + struct av_decision *avd, + struct operation *ops); struct selinux_mapping { u16 value; /* policy value */ @@ -566,7 +567,8 @@ static void type_attribute_bounds_av(struct context *scontext, context_struct_compute_av(&lo_scontext, tcontext, tclass, - &lo_avd); + &lo_avd, + NULL); if ((lo_avd.allowed & avd->allowed) == avd->allowed) return; /* no masked permission */ masked = ~lo_avd.allowed & avd->allowed; @@ -581,7 +583,8 @@ static void type_attribute_bounds_av(struct context *scontext, context_struct_compute_av(scontext, &lo_tcontext, tclass, - &lo_avd); + &lo_avd, + NULL); if ((lo_avd.allowed & avd->allowed) == avd->allowed) return; /* no masked permission */ masked = ~lo_avd.allowed & avd->allowed; @@ -597,7 +600,8 @@ static void type_attribute_bounds_av(struct context *scontext, context_struct_compute_av(&lo_scontext, &lo_tcontext, tclass, - &lo_avd); + &lo_avd, + NULL); if ((lo_avd.allowed & avd->allowed) == avd->allowed) return; /* no masked permission */ masked = ~lo_avd.allowed & avd->allowed; @@ -613,14 +617,39 @@ static void type_attribute_bounds_av(struct context *scontext, } } +/* flag ioctl types that have operation permissions */ +void services_compute_operation_type( + struct operation *ops, + struct avtab_node *node) +{ + u8 type; + unsigned int i; + + if (node->key.specified & AVTAB_OPTYPE) { + /* if allowing one or more complete types */ + for (i = 0; i < ARRAY_SIZE(ops->type); i++) + ops->type[i] |= node->datum.u.ops->op.perms[i]; + } else { + /* if allowing operations within a type */ + type = node->datum.u.ops->type; + security_operation_set(ops->type, type); + } + + /* If no ioctl commands are allowed, ignore auditallow and auditdeny */ + if (node->key.specified & AVTAB_OPTYPE_ALLOWED || + node->key.specified & AVTAB_OPNUM_ALLOWED) + ops->len = 1; +} + /* - * Compute access vectors based on a context structure pair for - * the permissions in a particular class. + * Compute access vectors and operations ranges 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 context *tcontext, + u16 tclass, + struct av_decision *avd, + struct operation *ops) { struct constraint_node *constraint; struct role_allow *ra; @@ -634,6 +663,10 @@ static void context_struct_compute_av(struct context *scontext, avd->allowed = 0; avd->auditallow = 0; avd->auditdeny = 0xffffffff; + if (ops) { + memset(&ops->type, 0, sizeof(ops->type)); + ops->len = 0; + } if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { if (printk_ratelimit()) @@ -648,7 +681,7 @@ static void context_struct_compute_av(struct context *scontext, * this permission check, then use it. */ avkey.target_class = tclass; - avkey.specified = AVTAB_AV; + avkey.specified = AVTAB_AV | AVTAB_OP; 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); @@ -661,15 +694,17 @@ static void context_struct_compute_av(struct context *scontext, node; node = avtab_search_node_next(node, avkey.specified)) { if (node->key.specified == AVTAB_ALLOWED) - avd->allowed |= node->datum.data; + avd->allowed |= node->datum.u.data; else if (node->key.specified == AVTAB_AUDITALLOW) - avd->auditallow |= node->datum.data; + avd->auditallow |= node->datum.u.data; else if (node->key.specified == AVTAB_AUDITDENY) - avd->auditdeny &= node->datum.data; + avd->auditdeny &= node->datum.u.data; + else if (ops && (node->key.specified & AVTAB_OP)) + services_compute_operation_type(ops, node); } /* Check conditional av table for additional permissions */ - cond_compute_av(&policydb.te_cond_avtab, &avkey, avd); + cond_compute_av(&policydb.te_cond_avtab, &avkey, avd, ops); } } @@ -900,13 +935,139 @@ static void avd_init(struct av_decision *avd) avd->flags = 0; } +void services_compute_operation_num(struct operation_decision *od, + struct avtab_node *node) +{ + unsigned int i; + + if (node->key.specified & AVTAB_OPNUM) { + if (od->type != node->datum.u.ops->type) + return; + } else { + if (!security_operation_test(node->datum.u.ops->op.perms, + od->type)) + return; + } + + if (node->key.specified == AVTAB_OPTYPE_ALLOWED) { + od->specified |= OPERATION_ALLOWED; + memset(od->allowed->perms, 0xff, + sizeof(od->allowed->perms)); + } else if (node->key.specified == AVTAB_OPTYPE_AUDITALLOW) { + od->specified |= OPERATION_AUDITALLOW; + memset(od->auditallow->perms, 0xff, + sizeof(od->auditallow->perms)); + } else if (node->key.specified == AVTAB_OPTYPE_DONTAUDIT) { + od->specified |= OPERATION_DONTAUDIT; + memset(od->dontaudit->perms, 0xff, + sizeof(od->dontaudit->perms)); + } else if (node->key.specified == AVTAB_OPNUM_ALLOWED) { + od->specified |= OPERATION_ALLOWED; + for (i = 0; i < ARRAY_SIZE(od->allowed->perms); i++) + od->allowed->perms[i] |= + node->datum.u.ops->op.perms[i]; + } else if (node->key.specified == AVTAB_OPNUM_AUDITALLOW) { + od->specified |= OPERATION_AUDITALLOW; + for (i = 0; i < ARRAY_SIZE(od->auditallow->perms); i++) + od->auditallow->perms[i] |= + node->datum.u.ops->op.perms[i]; + } else if (node->key.specified == AVTAB_OPNUM_DONTAUDIT) { + od->specified |= OPERATION_DONTAUDIT; + for (i = 0; i < ARRAY_SIZE(od->dontaudit->perms); i++) + od->dontaudit->perms[i] |= + node->datum.u.ops->op.perms[i]; + } else { + BUG(); + } +} + +void security_compute_operation(u32 ssid, + u32 tsid, + u16 orig_tclass, + u8 type, + struct operation_decision *od) +{ + u16 tclass; + struct context *scontext, *tcontext; + struct avtab_key avkey; + struct avtab_node *node; + struct ebitmap *sattr, *tattr; + struct ebitmap_node *snode, *tnode; + unsigned int i, j; + + od->type = type; + od->specified = 0; + memset(od->allowed->perms, 0, sizeof(od->allowed->perms)); + memset(od->auditallow->perms, 0, sizeof(od->auditallow->perms)); + memset(od->dontaudit->perms, 0, sizeof(od->dontaudit->perms)); + + read_lock(&policy_rwlock); + 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; + } + + tcontext = sidtab_search(&sidtab, tsid); + if (!tcontext) { + printk(KERN_ERR "SELinux: %s: unrecognized SID %d\n", + __func__, tsid); + goto out; + } + + tclass = unmap_class(orig_tclass); + if (unlikely(orig_tclass && !tclass)) { + if (policydb.allow_unknown) + goto allow; + goto out; + } + + + if (unlikely(!tclass || tclass > policydb.p_classes.nprim)) { + if (printk_ratelimit()) + printk(KERN_WARNING "SELinux: Invalid class %hu\n", tclass); + goto out; + } + + avkey.target_class = tclass; + avkey.specified = AVTAB_OP; + 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; + node = avtab_search_node_next(node, avkey.specified)) + services_compute_operation_num(od, node); + cond_compute_operation(&policydb.te_cond_avtab, + &avkey, od); + } + } +out: + read_unlock(&policy_rwlock); + return; +allow: + memset(od->allowed->perms, 0xff, sizeof(od->allowed->perms)); + goto out; +} /** * security_compute_av - Compute access vector decisions. * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class * @avd: access vector decisions + * @od: operation decisions * * Compute a set of access vector decisions based on the * SID pair (@ssid, @tsid) for the permissions in @tclass. @@ -914,13 +1075,15 @@ static void avd_init(struct av_decision *avd) void security_compute_av(u32 ssid, u32 tsid, u16 orig_tclass, - struct av_decision *avd) + struct av_decision *avd, + struct operation *ops) { u16 tclass; struct context *scontext = NULL, *tcontext = NULL; read_lock(&policy_rwlock); avd_init(avd); + ops->len = 0; if (!ss_initialized) goto allow; @@ -948,7 +1111,7 @@ void security_compute_av(u32 ssid, goto allow; goto out; } - context_struct_compute_av(scontext, tcontext, tclass, avd); + context_struct_compute_av(scontext, tcontext, tclass, avd, ops); map_decision(orig_tclass, avd, policydb.allow_unknown); out: read_unlock(&policy_rwlock); @@ -994,7 +1157,7 @@ void security_compute_av_user(u32 ssid, goto out; } - context_struct_compute_av(scontext, tcontext, tclass, avd); + context_struct_compute_av(scontext, tcontext, tclass, avd, NULL); out: read_unlock(&policy_rwlock); return; @@ -1231,6 +1394,10 @@ 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; @@ -1391,6 +1558,7 @@ static int security_compute_sid(u32 ssid, 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; @@ -1439,12 +1607,20 @@ 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. */ @@ -1452,16 +1628,31 @@ static int security_compute_sid(u32 ssid, break; } - /* Set the role and type to default values. */ - if ((tclass == policydb.process_class) || (sock == true)) { - /* 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. */ @@ -1484,7 +1675,7 @@ static int security_compute_sid(u32 ssid, if (avdatum) { /* Use the type from the type transition/member/change rule. */ - newcontext.type = avdatum->data; + newcontext.type = avdatum->u.data; } /* if we have a objname this is a file trans check so check those rules */ |