| Author | Tokens | Token Proportion | Commits | Commit Proportion |
|---|---|---|---|---|
| Stephen D. Smalley | 5785 | 34.61% | 35 | 16.59% |
| Andrew Morton | 3073 | 18.39% | 6 | 2.84% |
| Ondrej Mosnáček | 1260 | 7.54% | 23 | 10.90% |
| Darrel Goeddel | 1222 | 7.31% | 5 | 2.37% |
| Jeff Vander Stoep | 1067 | 6.38% | 2 | 0.95% |
| Eric Paris | 955 | 5.71% | 26 | 12.32% |
| Venkat Yekkirala | 537 | 3.21% | 5 | 2.37% |
| KaiGai Kohei | 518 | 3.10% | 7 | 3.32% |
| Paul Moore | 434 | 2.60% | 25 | 11.85% |
| Christopher J. PeBenito | 421 | 2.52% | 2 | 0.95% |
| Daniel Jurgens | 219 | 1.31% | 2 | 0.95% |
| Chad Sellers | 177 | 1.06% | 1 | 0.47% |
| Ahmed S. Darwish | 116 | 0.69% | 2 | 0.95% |
| Guido Trentalancia | 109 | 0.65% | 1 | 0.47% |
| Lakshmi Ramasubramanian | 89 | 0.53% | 2 | 0.95% |
| Richard Guy Briggs | 80 | 0.48% | 4 | 1.90% |
| James Morris | 74 | 0.44% | 8 | 3.79% |
| Harry Ciao | 74 | 0.44% | 2 | 0.95% |
| Dan Carpenter | 67 | 0.40% | 2 | 0.95% |
| Andrew Perepechko | 59 | 0.35% | 1 | 0.47% |
| Christian Göttsche | 54 | 0.32% | 8 | 3.79% |
| Rasmus Villemoes | 38 | 0.23% | 4 | 1.90% |
| Steve Grubb | 31 | 0.19% | 2 | 0.95% |
| Xiu Jianfeng | 30 | 0.18% | 1 | 0.47% |
| pender01 | 30 | 0.18% | 1 | 0.47% |
| Waiman Long | 29 | 0.17% | 1 | 0.47% |
| Tom Rix | 21 | 0.13% | 1 | 0.47% |
| Kohei Kaigai | 19 | 0.11% | 1 | 0.47% |
| Kent Overstreet | 18 | 0.11% | 1 | 0.47% |
| Al Viro | 14 | 0.08% | 1 | 0.47% |
| Anand V. Avati | 8 | 0.05% | 1 | 0.47% |
| Austin Kim | 8 | 0.05% | 1 | 0.47% |
| Linus Torvalds | 7 | 0.04% | 2 | 0.95% |
| Tim Gardner | 7 | 0.04% | 1 | 0.47% |
| Sachin Grover | 6 | 0.04% | 1 | 0.47% |
| Eric W. Biedermann | 6 | 0.04% | 1 | 0.47% |
| Jesper Juhl | 6 | 0.04% | 1 | 0.47% |
| David Woodhouse | 6 | 0.04% | 1 | 0.47% |
| Nikolay Aleksandrov | 4 | 0.02% | 1 | 0.47% |
| Casey Schaufler | 4 | 0.02% | 2 | 0.95% |
| Trent Jaeger | 3 | 0.02% | 1 | 0.47% |
| Serge E. Hallyn | 3 | 0.02% | 1 | 0.47% |
| Stephen Rothwell | 3 | 0.02% | 1 | 0.47% |
| Ruiqi Gong | 3 | 0.02% | 1 | 0.47% |
| Prarit Bhargava | 3 | 0.02% | 1 | 0.47% |
| James Carter | 3 | 0.02% | 1 | 0.47% |
| Julia Lawall | 2 | 0.01% | 1 | 0.47% |
| Colin Ian King | 2 | 0.01% | 1 | 0.47% |
| Chris Wright | 2 | 0.01% | 1 | 0.47% |
| David Howells | 1 | 0.01% | 1 | 0.47% |
| Steve G | 1 | 0.01% | 1 | 0.47% |
| Lucas De Marchi | 1 | 0.01% | 1 | 0.47% |
| Harvey Harrison | 1 | 0.01% | 1 | 0.47% |
| SF Markus Elfring | 1 | 0.01% | 1 | 0.47% |
| Jann Horn | 1 | 0.01% | 1 | 0.47% |
| Jiri Kosina | 1 | 0.01% | 1 | 0.47% |
| Thomas Gleixner | 1 | 0.01% | 1 | 0.47% |
| Total | 16714 | 211 |
// SPDX-License-Identifier: GPL-2.0-only /* * Implementation of the security services. * * Authors : Stephen Smalley, <stephen.smalley.work@gmail.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 * * 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> */ #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 <linux/vmalloc.h> #include <linux/lsm_hooks.h> #include <net/netlabel.h> #include "flask.h" #include "avc.h" #include "avc_ss.h" #include "security.h" #include "context.h" #include "policydb.h" #include "sidtab.h" #include "services.h" #include "conditional.h" #include "mls.h" #include "objsec.h" #include "netlabel.h" #include "xfrm.h" #include "ebitmap.h" #include "audit.h" #include "policycap_names.h" #include "ima.h" struct selinux_policy_convert_data { struct convert_context_args args; struct sidtab_convert_params sidtab_params; }; /* Forward declaration. */ static int context_struct_to_string(struct policydb *policydb, struct context *context, char **scontext, u32 *scontext_len); static int sidtab_entry_to_string(struct policydb *policydb, struct sidtab *sidtab, struct sidtab_entry *entry, char **scontext, u32 *scontext_len); static void context_struct_compute_av(struct policydb *policydb, struct context *scontext, struct context *tcontext, u16 tclass, struct av_decision *avd, struct extended_perms *xperms); static int selinux_set_mapping(struct policydb *pol, const struct security_class_mapping *map, struct selinux_map *out_map) { u16 i, j; 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->mapping = kcalloc(++i, sizeof(*out_map->mapping), GFP_ATOMIC); if (!out_map->mapping) return -ENOMEM; /* Store the raw class and permission values */ j = 0; while (map[j].name) { const struct security_class_mapping *p_in = map + (j++); struct selinux_mapping *p_out = out_map->mapping + j; u16 k; /* 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) { pr_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[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]) { pr_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) pr_info("SELinux: the above unknown classes and permissions will be %s\n", pol->allow_unknown ? "allowed" : "denied"); out_map->size = i; return 0; err: kfree(out_map->mapping); out_map->mapping = NULL; return -EINVAL; } /* * Get real, policy values from mapped values */ static u16 unmap_class(struct selinux_map *map, u16 tclass) { if (tclass < map->size) return map->mapping[tclass].value; return tclass; } /* * Get kernel value for class from its policy value */ static u16 map_class(struct selinux_map *map, u16 pol_value) { u16 i; for (i = 1; i < map->size; i++) { if (map->mapping[i].value == pol_value) return i; } return SECCLASS_NULL; } static void map_decision(struct selinux_map *map, u16 tclass, struct av_decision *avd, int allow_unknown) { if (tclass < map->size) { struct selinux_mapping *mapping = &map->mapping[tclass]; unsigned int i, n = mapping->num_perms; u32 result; for (i = 0, result = 0; i < n; i++) { if (avd->allowed & mapping->perms[i]) result |= (u32)1<<i; if (allow_unknown && !mapping->perms[i]) result |= (u32)1<<i; } avd->allowed = result; for (i = 0, result = 0; i < n; i++) if (avd->auditallow & mapping->perms[i]) result |= (u32)1<<i; avd->auditallow = result; for (i = 0, result = 0; i < n; i++) { if (avd->auditdeny & mapping->perms[i]) result |= (u32)1<<i; if (!allow_unknown && !mapping->perms[i]) result |= (u32)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 |= (u32)1<<i; avd->auditdeny = result; } } int security_mls_enabled(void) { int mls_enabled; struct selinux_policy *policy; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); mls_enabled = policy->policydb.mls_enabled; rcu_read_unlock(); return mls_enabled; } /* * Return the boolean value of a constraint expression * when it is applied to the specified source and target * security contexts. * * xcontext is a special beast... It is used by the validatetrans rules * only. For these rules, scontext is the context before the transition, * tcontext is the context after the transition, and xcontext is the context * of the process performing the transition. All other callers of * constraint_expr_eval should pass in NULL for xcontext. */ static int constraint_expr_eval(struct policydb *policydb, struct context *scontext, struct context *tcontext, struct context *xcontext, struct constraint_expr *cexpr) { u32 val1, val2; struct context *c; struct role_datum *r1, *r2; struct mls_level *l1, *l2; struct constraint_expr *e; int s[CEXPR_MAXDEPTH]; int sp = -1; for (e = cexpr; e; e = e->next) { switch (e->expr_type) { case CEXPR_NOT: BUG_ON(sp < 0); s[sp] = !s[sp]; break; case CEXPR_AND: BUG_ON(sp < 1); sp--; s[sp] &= s[sp + 1]; break; case CEXPR_OR: BUG_ON(sp < 1); sp--; s[sp] |= s[sp + 1]; break; case CEXPR_ATTR: if (sp == (CEXPR_MAXDEPTH - 1)) return 0; switch (e->attr) { case CEXPR_USER: val1 = scontext->user; val2 = tcontext->user; break; case CEXPR_TYPE: val1 = scontext->type; val2 = tcontext->type; break; case CEXPR_ROLE: val1 = scontext->role; val2 = tcontext->role; r1 = policydb->role_val_to_struct[val1 - 1]; r2 = policydb->role_val_to_struct[val2 - 1]; switch (e->op) { case CEXPR_DOM: s[++sp] = ebitmap_get_bit(&r1->dominates, val2 - 1); continue; case CEXPR_DOMBY: s[++sp] = ebitmap_get_bit(&r2->dominates, val1 - 1); continue; case CEXPR_INCOMP: s[++sp] = (!ebitmap_get_bit(&r1->dominates, val2 - 1) && !ebitmap_get_bit(&r2->dominates, val1 - 1)); continue; default: break; } break; case CEXPR_L1L2: l1 = &(scontext->range.level[0]); l2 = &(tcontext->range.level[0]); goto mls_ops; case CEXPR_L1H2: l1 = &(scontext->range.level[0]); l2 = &(tcontext->range.level[1]); goto mls_ops; case CEXPR_H1L2: l1 = &(scontext->range.level[1]); l2 = &(tcontext->range.level[0]); goto mls_ops; case CEXPR_H1H2: l1 = &(scontext->range.level[1]); l2 = &(tcontext->range.level[1]); goto mls_ops; case CEXPR_L1H1: l1 = &(scontext->range.level[0]); l2 = &(scontext->range.level[1]); goto mls_ops; case CEXPR_L2H2: l1 = &(tcontext->range.level[0]); l2 = &(tcontext->range.level[1]); goto mls_ops; mls_ops: switch (e->op) { case CEXPR_EQ: s[++sp] = mls_level_eq(l1, l2); continue; case CEXPR_NEQ: s[++sp] = !mls_level_eq(l1, l2); continue; case CEXPR_DOM: s[++sp] = mls_level_dom(l1, l2); continue; case CEXPR_DOMBY: s[++sp] = mls_level_dom(l2, l1); continue; case CEXPR_INCOMP: s[++sp] = mls_level_incomp(l2, l1); continue; default: BUG(); return 0; } break; default: BUG(); return 0; } switch (e->op) { case CEXPR_EQ: s[++sp] = (val1 == val2); break; case CEXPR_NEQ: s[++sp] = (val1 != val2); break; default: BUG(); return 0; } break; case CEXPR_NAMES: if (sp == (CEXPR_MAXDEPTH-1)) return 0; c = scontext; if (e->attr & CEXPR_TARGET) c = tcontext; else if (e->attr & CEXPR_XTARGET) { c = xcontext; if (!c) { BUG(); return 0; } } if (e->attr & CEXPR_USER) val1 = c->user; else if (e->attr & CEXPR_ROLE) val1 = c->role; else if (e->attr & CEXPR_TYPE) val1 = c->type; else { BUG(); return 0; } switch (e->op) { case CEXPR_EQ: s[++sp] = ebitmap_get_bit(&e->names, val1 - 1); break; case CEXPR_NEQ: s[++sp] = !ebitmap_get_bit(&e->names, val1 - 1); break; default: BUG(); return 0; } break; default: BUG(); return 0; } } BUG_ON(sp != 0); return s[0]; } /* * 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 policydb *policydb, 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(policydb, scontext, &scontext_name, &length) < 0) goto out; if (context_struct_to_string(policydb, tcontext, &tcontext_name, &length) < 0) goto out; /* audit a message */ ab = audit_log_start(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); } /* * security_boundary_permission - drops violated permissions * on boundary constraint. */ static void type_attribute_bounds_av(struct policydb *policydb, struct context *scontext, struct context *tcontext, u16 tclass, struct av_decision *avd) { struct context lo_scontext; struct context lo_tcontext, *tcontextp = tcontext; struct av_decision lo_avd; struct type_datum *source; struct type_datum *target; u32 masked = 0; source = policydb->type_val_to_struct[scontext->type - 1]; BUG_ON(!source); if (!source->bounds) return; target = policydb->type_val_to_struct[tcontext->type - 1]; BUG_ON(!target); memset(&lo_avd, 0, sizeof(lo_avd)); memcpy(&lo_scontext, scontext, sizeof(lo_scontext)); lo_scontext.type = source->bounds; if (target->bounds) { memcpy(&lo_tcontext, tcontext, sizeof(lo_tcontext)); lo_tcontext.type = target->bounds; tcontextp = &lo_tcontext; } context_struct_compute_av(policydb, &lo_scontext, tcontextp, tclass, &lo_avd, NULL); masked = ~lo_avd.allowed & avd->allowed; if (likely(!masked)) return; /* no masked permission */ /* mask violated permissions */ avd->allowed &= ~masked; /* audit masked permissions */ security_dump_masked_av(policydb, scontext, tcontext, tclass, masked, "bounds"); } /* * flag which drivers have permissions * only looking for ioctl based extended permissions */ void services_compute_xperms_drivers( struct extended_perms *xperms, struct avtab_node *node) { unsigned int i; if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { /* if one or more driver has all permissions allowed */ for (i = 0; i < ARRAY_SIZE(xperms->drivers.p); i++) xperms->drivers.p[i] |= node->datum.u.xperms->perms.p[i]; } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { /* if allowing permissions within a driver */ security_xperm_set(xperms->drivers.p, node->datum.u.xperms->driver); } xperms->len = 1; } /* * Compute access vectors and extended permissions based on a context * structure pair for the permissions in a particular class. */ static void context_struct_compute_av(struct policydb *policydb, struct context *scontext, struct context *tcontext, u16 tclass, struct av_decision *avd, struct extended_perms *xperms) { struct constraint_node *constraint; struct role_allow *ra; struct avtab_key avkey; struct avtab_node *node; struct class_datum *tclass_datum; struct ebitmap *sattr, *tattr; struct ebitmap_node *snode, *tnode; unsigned int i, j; avd->allowed = 0; avd->auditallow = 0; avd->auditdeny = 0xffffffff; if (xperms) { memset(&xperms->drivers, 0, sizeof(xperms->drivers)); xperms->len = 0; } if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { if (printk_ratelimit()) pr_warn("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 * this permission check, then use it. */ avkey.target_class = tclass; avkey.specified = AVTAB_AV | AVTAB_XPERMS; sattr = &policydb->type_attr_map_array[scontext->type - 1]; tattr = &policydb->type_attr_map_array[tcontext->type - 1]; 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)) { if (node->key.specified == AVTAB_ALLOWED) avd->allowed |= node->datum.u.data; else if (node->key.specified == AVTAB_AUDITALLOW) avd->auditallow |= node->datum.u.data; else if (node->key.specified == AVTAB_AUDITDENY) avd->auditdeny &= node->datum.u.data; else if (xperms && (node->key.specified & AVTAB_XPERMS)) services_compute_xperms_drivers(xperms, node); } /* Check conditional av table for additional permissions */ cond_compute_av(&policydb->te_cond_avtab, &avkey, avd, xperms); } } /* * Remove any permissions prohibited by a constraint (this includes * the MLS policy). */ constraint = tclass_datum->constraints; while (constraint) { if ((constraint->permissions & (avd->allowed)) && !constraint_expr_eval(policydb, scontext, tcontext, NULL, constraint->expr)) { avd->allowed &= ~(constraint->permissions); } constraint = constraint->next; } /* * If checking process transition permission and the * role is changing, then check the (current_role, new_role) * pair. */ 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 && tcontext->role == ra->new_role) break; } if (!ra) avd->allowed &= ~policydb->process_trans_perms; } /* * 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(policydb, scontext, tcontext, tclass, avd); } static int security_validtrans_handle_fail(struct selinux_policy *policy, struct sidtab_entry *oentry, struct sidtab_entry *nentry, struct sidtab_entry *tentry, u16 tclass) { struct policydb *p = &policy->policydb; struct sidtab *sidtab = policy->sidtab; char *o = NULL, *n = NULL, *t = NULL; u32 olen, nlen, tlen; if (sidtab_entry_to_string(p, sidtab, oentry, &o, &olen)) goto out; if (sidtab_entry_to_string(p, sidtab, nentry, &n, &nlen)) goto out; if (sidtab_entry_to_string(p, sidtab, tentry, &t, &tlen)) goto out; audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR, "op=security_validate_transition seresult=denied" " oldcontext=%s newcontext=%s taskcontext=%s tclass=%s", o, n, t, sym_name(p, SYM_CLASSES, tclass-1)); out: kfree(o); kfree(n); kfree(t); if (!enforcing_enabled()) return 0; return -EPERM; } static int security_compute_validatetrans(u32 oldsid, u32 newsid, u32 tasksid, u16 orig_tclass, bool user) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct sidtab_entry *oentry; struct sidtab_entry *nentry; struct sidtab_entry *tentry; struct class_datum *tclass_datum; struct constraint_node *constraint; u16 tclass; int rc = 0; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; if (!user) tclass = unmap_class(&policy->map, orig_tclass); else tclass = orig_tclass; if (!tclass || tclass > policydb->p_classes.nprim) { rc = -EINVAL; goto out; } tclass_datum = policydb->class_val_to_struct[tclass - 1]; oentry = sidtab_search_entry(sidtab, oldsid); if (!oentry) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, oldsid); rc = -EINVAL; goto out; } nentry = sidtab_search_entry(sidtab, newsid); if (!nentry) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, newsid); rc = -EINVAL; goto out; } tentry = sidtab_search_entry(sidtab, tasksid); if (!tentry) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, tasksid); rc = -EINVAL; goto out; } constraint = tclass_datum->validatetrans; while (constraint) { if (!constraint_expr_eval(policydb, &oentry->context, &nentry->context, &tentry->context, constraint->expr)) { if (user) rc = -EPERM; else rc = security_validtrans_handle_fail(policy, oentry, nentry, tentry, tclass); goto out; } constraint = constraint->next; } out: rcu_read_unlock(); return rc; } int security_validate_transition_user(u32 oldsid, u32 newsid, u32 tasksid, u16 tclass) { return security_compute_validatetrans(oldsid, newsid, tasksid, tclass, true); } int security_validate_transition(u32 oldsid, u32 newsid, u32 tasksid, u16 orig_tclass) { return security_compute_validatetrans(oldsid, newsid, tasksid, orig_tclass, false); } /* * 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 selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct sidtab_entry *old_entry, *new_entry; struct type_datum *type; u32 index; int rc; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; rc = -EINVAL; old_entry = sidtab_search_entry(sidtab, old_sid); if (!old_entry) { pr_err("SELinux: %s: unrecognized SID %u\n", __func__, old_sid); goto out; } rc = -EINVAL; new_entry = sidtab_search_entry(sidtab, new_sid); if (!new_entry) { pr_err("SELinux: %s: unrecognized SID %u\n", __func__, new_sid); goto out; } rc = 0; /* type/domain unchanged */ if (old_entry->context.type == new_entry->context.type) goto out; index = new_entry->context.type; while (true) { type = policydb->type_val_to_struct[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_entry->context.type) break; index = type->bounds; } if (rc) { char *old_name = NULL; char *new_name = NULL; u32 length; if (!sidtab_entry_to_string(policydb, sidtab, old_entry, &old_name, &length) && !sidtab_entry_to_string(policydb, sidtab, new_entry, &new_name, &length)) { audit_log(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR, "op=security_bounded_transition " "seresult=denied " "oldcontext=%s newcontext=%s", old_name, new_name); } kfree(new_name); kfree(old_name); } out: rcu_read_unlock(); return rc; } static void avd_init(struct selinux_policy *policy, struct av_decision *avd) { avd->allowed = 0; avd->auditallow = 0; avd->auditdeny = 0xffffffff; if (policy) avd->seqno = policy->latest_granting; else avd->seqno = 0; avd->flags = 0; } void services_compute_xperms_decision(struct extended_perms_decision *xpermd, struct avtab_node *node) { unsigned int i; if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { if (xpermd->driver != node->datum.u.xperms->driver) return; } else if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { if (!security_xperm_test(node->datum.u.xperms->perms.p, xpermd->driver)) return; } else { BUG(); } if (node->key.specified == AVTAB_XPERMS_ALLOWED) { xpermd->used |= XPERMS_ALLOWED; if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p)); } if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { for (i = 0; i < ARRAY_SIZE(xpermd->allowed->p); i++) xpermd->allowed->p[i] |= node->datum.u.xperms->perms.p[i]; } } else if (node->key.specified == AVTAB_XPERMS_AUDITALLOW) { xpermd->used |= XPERMS_AUDITALLOW; if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { memset(xpermd->auditallow->p, 0xff, sizeof(xpermd->auditallow->p)); } if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { for (i = 0; i < ARRAY_SIZE(xpermd->auditallow->p); i++) xpermd->auditallow->p[i] |= node->datum.u.xperms->perms.p[i]; } } else if (node->key.specified == AVTAB_XPERMS_DONTAUDIT) { xpermd->used |= XPERMS_DONTAUDIT; if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLDRIVER) { memset(xpermd->dontaudit->p, 0xff, sizeof(xpermd->dontaudit->p)); } if (node->datum.u.xperms->specified == AVTAB_XPERMS_IOCTLFUNCTION) { for (i = 0; i < ARRAY_SIZE(xpermd->dontaudit->p); i++) xpermd->dontaudit->p[i] |= node->datum.u.xperms->perms.p[i]; } } else { BUG(); } } void security_compute_xperms_decision(u32 ssid, u32 tsid, u16 orig_tclass, u8 driver, struct extended_perms_decision *xpermd) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; 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; xpermd->driver = driver; xpermd->used = 0; memset(xpermd->allowed->p, 0, sizeof(xpermd->allowed->p)); memset(xpermd->auditallow->p, 0, sizeof(xpermd->auditallow->p)); memset(xpermd->dontaudit->p, 0, sizeof(xpermd->dontaudit->p)); rcu_read_lock(); if (!selinux_initialized()) goto allow; policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, ssid); goto out; } tcontext = sidtab_search(sidtab, tsid); if (!tcontext) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, tsid); goto out; } tclass = unmap_class(&policy->map, orig_tclass); if (unlikely(orig_tclass && !tclass)) { if (policydb->allow_unknown) goto allow; goto out; } if (unlikely(!tclass || tclass > policydb->p_classes.nprim)) { pr_warn_ratelimited("SELinux: Invalid class %hu\n", tclass); goto out; } avkey.target_class = tclass; avkey.specified = AVTAB_XPERMS; sattr = &policydb->type_attr_map_array[scontext->type - 1]; tattr = &policydb->type_attr_map_array[tcontext->type - 1]; 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_xperms_decision(xpermd, node); cond_compute_xperms(&policydb->te_cond_avtab, &avkey, xpermd); } } out: rcu_read_unlock(); return; allow: memset(xpermd->allowed->p, 0xff, sizeof(xpermd->allowed->p)); goto out; } /** * security_compute_av - Compute access vector decisions. * @ssid: source security identifier * @tsid: target security identifier * @orig_tclass: target security class * @avd: access vector decisions * @xperms: extended permissions * * Compute a set of access vector decisions based on the * SID pair (@ssid, @tsid) for the permissions in @tclass. */ void security_compute_av(u32 ssid, u32 tsid, u16 orig_tclass, struct av_decision *avd, struct extended_perms *xperms) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; u16 tclass; struct context *scontext = NULL, *tcontext = NULL; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); avd_init(policy, avd); xperms->len = 0; if (!selinux_initialized()) goto allow; policydb = &policy->policydb; sidtab = policy->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { pr_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) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, tsid); goto out; } tclass = unmap_class(&policy->map, orig_tclass); if (unlikely(orig_tclass && !tclass)) { if (policydb->allow_unknown) goto allow; goto out; } context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, xperms); map_decision(&policy->map, orig_tclass, avd, policydb->allow_unknown); out: rcu_read_unlock(); return; allow: avd->allowed = 0xffffffff; goto out; } void security_compute_av_user(u32 ssid, u32 tsid, u16 tclass, struct av_decision *avd) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct context *scontext = NULL, *tcontext = NULL; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); avd_init(policy, avd); if (!selinux_initialized()) goto allow; policydb = &policy->policydb; sidtab = policy->sidtab; scontext = sidtab_search(sidtab, ssid); if (!scontext) { pr_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) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, tsid); goto out; } if (unlikely(!tclass)) { if (policydb->allow_unknown) goto allow; goto out; } context_struct_compute_av(policydb, scontext, tcontext, tclass, avd, NULL); out: rcu_read_unlock(); return; allow: avd->allowed = 0xffffffff; goto out; } /* * Write the security context string representation of * the context structure `context' 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. */ static int context_struct_to_string(struct policydb *p, struct context *context, char **scontext, u32 *scontext_len) { char *scontextp; 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(sym_name(p, SYM_USERS, context->user - 1)) + 1; *scontext_len += strlen(sym_name(p, SYM_ROLES, context->role - 1)) + 1; *scontext_len += strlen(sym_name(p, SYM_TYPES, context->type - 1)) + 1; *scontext_len += mls_compute_context_len(p, context); if (!scontext) return 0; /* Allocate space for the context; caller must free this space. */ scontextp = kmalloc(*scontext_len, GFP_ATOMIC); if (!scontextp) return -ENOMEM; *scontext = scontextp; /* * Copy the user name, role name and type name into the context. */ scontextp += sprintf(scontextp, "%s:%s:%s", sym_name(p, SYM_USERS, context->user - 1), sym_name(p, SYM_ROLES, context->role - 1), sym_name(p, SYM_TYPES, context->type - 1)); mls_sid_to_context(p, context, &scontextp); *scontextp = 0; return 0; } static int sidtab_entry_to_string(struct policydb *p, struct sidtab *sidtab, struct sidtab_entry *entry, char **scontext, u32 *scontext_len) { int rc = sidtab_sid2str_get(sidtab, entry, scontext, scontext_len); if (rc != -ENOENT) return rc; rc = context_struct_to_string(p, &entry->context, scontext, scontext_len); if (!rc && scontext) sidtab_sid2str_put(sidtab, entry, *scontext, *scontext_len); return rc; } #include "initial_sid_to_string.h" int security_sidtab_hash_stats(char *page) { struct selinux_policy *policy; int rc; if (!selinux_initialized()) { pr_err("SELinux: %s: called before initial load_policy\n", __func__); return -EINVAL; } rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); rc = sidtab_hash_stats(policy->sidtab, page); rcu_read_unlock(); return rc; } 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, int only_invalid) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct sidtab_entry *entry; int rc = 0; if (scontext) *scontext = NULL; *scontext_len = 0; if (!selinux_initialized()) { if (sid <= SECINITSID_NUM) { char *scontextp; const char *s; /* * Before the policy is loaded, translate * SECINITSID_INIT to "kernel", because systemd and * libselinux < 2.6 take a getcon_raw() result that is * both non-null and not "kernel" to mean that a policy * is already loaded. */ if (sid == SECINITSID_INIT) sid = SECINITSID_KERNEL; s = initial_sid_to_string[sid]; if (!s) return -EINVAL; *scontext_len = strlen(s) + 1; if (!scontext) return 0; scontextp = kmemdup(s, *scontext_len, GFP_ATOMIC); if (!scontextp) return -ENOMEM; *scontext = scontextp; return 0; } pr_err("SELinux: %s: called before initial " "load_policy on unknown SID %d\n", __func__, sid); return -EINVAL; } rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; if (force) entry = sidtab_search_entry_force(sidtab, sid); else entry = sidtab_search_entry(sidtab, sid); if (!entry) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, sid); rc = -EINVAL; goto out_unlock; } if (only_invalid && !entry->context.len) goto out_unlock; rc = sidtab_entry_to_string(policydb, sidtab, entry, scontext, scontext_len); out_unlock: rcu_read_unlock(); return rc; } /** * 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, 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, 0); } /** * security_sid_to_context_inval - Obtain a context for a given SID if it * is invalid. * @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, but only if the * context is invalid in the current policy. Set @scontext to point to * this string (or NULL if the context is valid) and set @scontext_len to * the length of the string (or 0 if the context is valid). */ int security_sid_to_context_inval(u32 sid, char **scontext, u32 *scontext_len) { return security_sid_to_context_core(sid, scontext, scontext_len, 1, 1); } /* * Caveat: Mutates scontext. */ static int string_to_context_struct(struct policydb *pol, struct sidtab *sidtabp, char *scontext, struct context *ctx, u32 def_sid) { struct role_datum *role; struct type_datum *typdatum; struct user_datum *usrdatum; char *scontextp, *p, oldc; int rc = 0; context_init(ctx); /* Parse the security context. */ rc = -EINVAL; scontextp = scontext; /* Extract the user. */ p = scontextp; while (*p && *p != ':') p++; if (*p == 0) goto out; *p++ = 0; usrdatum = symtab_search(&pol->p_users, scontextp); if (!usrdatum) goto out; ctx->user = usrdatum->value; /* Extract role. */ scontextp = p; while (*p && *p != ':') p++; if (*p == 0) goto out; *p++ = 0; role = symtab_search(&pol->p_roles, scontextp); if (!role) goto out; ctx->role = role->value; /* Extract type. */ scontextp = p; while (*p && *p != ':') p++; oldc = *p; *p++ = 0; typdatum = symtab_search(&pol->p_types, scontextp); if (!typdatum || typdatum->attribute) goto out; ctx->type = typdatum->value; rc = mls_context_to_sid(pol, oldc, p, ctx, sidtabp, def_sid); if (rc) goto out; /* Check the validity of the new context. */ rc = -EINVAL; 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) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; char *scontext2, *str = NULL; struct context context; int rc = 0; /* An empty security context is never valid. */ if (!scontext_len) return -EINVAL; /* Copy the string to allow changes and ensure a NUL terminator */ scontext2 = kmemdup_nul(scontext, scontext_len, gfp_flags); if (!scontext2) return -ENOMEM; if (!selinux_initialized()) { u32 i; for (i = 1; i < SECINITSID_NUM; i++) { const char *s = initial_sid_to_string[i]; if (s && !strcmp(s, scontext2)) { *sid = i; goto out; } } *sid = SECINITSID_KERNEL; goto out; } *sid = SECSID_NULL; if (force) { /* Save another copy for storing in uninterpreted form */ rc = -ENOMEM; str = kstrdup(scontext2, gfp_flags); if (!str) goto out; } retry: rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; rc = string_to_context_struct(policydb, sidtab, scontext2, &context, def_sid); if (rc == -EINVAL && force) { context.str = str; context.len = strlen(str) + 1; str = NULL; } else if (rc) goto out_unlock; rc = sidtab_context_to_sid(sidtab, &context, sid); if (rc == -ESTALE) { rcu_read_unlock(); if (context.str) { str = context.str; context.str = NULL; } context_destroy(&context); goto retry; } context_destroy(&context); out_unlock: rcu_read_unlock(); out: kfree(scontext2); kfree(str); return rc; } /** * security_context_to_sid - Obtain a SID for a given security context. * @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, gfp_t gfp) { return security_context_to_sid_core(scontext, scontext_len, sid, SECSID_NULL, gfp, 0); } int security_context_str_to_sid(const char *scontext, u32 *sid, gfp_t gfp) { return security_context_to_sid(scontext, strlen(scontext), sid, gfp); } /** * security_context_to_sid_default - Obtain a SID for a given security context, * falling back to specified default if needed. * * @scontext: security context * @scontext_len: length in bytes * @sid: security identifier, SID * @def_sid: default SID to assign on error * @gfp_flags: the allocator get-free-page (GFP) flags * * 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(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, SECSID_NULL, GFP_KERNEL, 1); } static int compute_sid_handle_invalid_context( struct selinux_policy *policy, struct sidtab_entry *sentry, struct sidtab_entry *tentry, u16 tclass, struct context *newcontext) { struct policydb *policydb = &policy->policydb; struct sidtab *sidtab = policy->sidtab; char *s = NULL, *t = NULL, *n = NULL; u32 slen, tlen, nlen; struct audit_buffer *ab; if (sidtab_entry_to_string(policydb, sidtab, sentry, &s, &slen)) goto out; if (sidtab_entry_to_string(policydb, sidtab, tentry, &t, &tlen)) goto out; if (context_struct_to_string(policydb, newcontext, &n, &nlen)) goto out; ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); if (!ab) goto out; audit_log_format(ab, "op=security_compute_sid invalid_context="); /* no need to record the NUL with untrusted strings */ audit_log_n_untrustedstring(ab, n, nlen - 1); audit_log_format(ab, " scontext=%s tcontext=%s tclass=%s", s, t, sym_name(policydb, SYM_CLASSES, tclass-1)); audit_log_end(ab); out: kfree(s); kfree(t); kfree(n); if (!enforcing_enabled()) return 0; return -EACCES; } static void filename_compute_type(struct policydb *policydb, struct context *newcontext, u32 stype, u32 ttype, u16 tclass, const char *objname) { struct filename_trans_key ft; struct filename_trans_datum *datum; /* * 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(&policydb->filename_trans_ttypes, ttype)) return; ft.ttype = ttype; ft.tclass = tclass; ft.name = objname; datum = policydb_filenametr_search(policydb, &ft); while (datum) { if (ebitmap_get_bit(&datum->stypes, stype - 1)) { newcontext->type = datum->otype; return; } datum = datum->next; } } static int security_compute_sid(u32 ssid, u32 tsid, u16 orig_tclass, u16 specified, const char *objname, u32 *out_sid, bool kern) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct class_datum *cladatum; struct context *scontext, *tcontext, newcontext; struct sidtab_entry *sentry, *tentry; struct avtab_key avkey; struct avtab_node *avnode, *node; u16 tclass; int rc = 0; bool sock; if (!selinux_initialized()) { switch (orig_tclass) { case SECCLASS_PROCESS: /* kernel value */ *out_sid = ssid; break; default: *out_sid = tsid; break; } goto out; } retry: cladatum = NULL; context_init(&newcontext); rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); if (kern) { tclass = unmap_class(&policy->map, orig_tclass); sock = security_is_socket_class(orig_tclass); } else { tclass = orig_tclass; sock = security_is_socket_class(map_class(&policy->map, tclass)); } policydb = &policy->policydb; sidtab = policy->sidtab; sentry = sidtab_search_entry(sidtab, ssid); if (!sentry) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, ssid); rc = -EINVAL; goto out_unlock; } tentry = sidtab_search_entry(sidtab, tsid); if (!tentry) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, tsid); rc = -EINVAL; goto out_unlock; } scontext = &sentry->context; tcontext = &tentry->context; 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: 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. */ newcontext.user = tcontext->user; break; } /* 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) 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) { /* 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. */ avkey.source_type = scontext->type; avkey.target_type = tcontext->type; avkey.target_class = tclass; avkey.specified = specified; avnode = avtab_search_node(&policydb->te_avtab, &avkey); /* If no permanent rule, also check for enabled conditional rules */ if (!avnode) { node = avtab_search_node(&policydb->te_cond_avtab, &avkey); for (; node; node = avtab_search_node_next(node, specified)) { if (node->key.specified & AVTAB_ENABLED) { avnode = node; break; } } } if (avnode) { /* Use the type from the type transition/member/change rule. */ newcontext.type = avnode->datum.u.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 (specified & AVTAB_TRANSITION) { /* Look for a role transition rule. */ struct role_trans_datum *rtd; struct role_trans_key rtk = { .role = scontext->role, .type = tcontext->type, .tclass = tclass, }; rtd = policydb_roletr_search(policydb, &rtk); if (rtd) newcontext.role = rtd->new_role; } /* Set the MLS attributes. This is done last because it may allocate memory. */ rc = mls_compute_sid(policydb, scontext, tcontext, tclass, specified, &newcontext, sock); if (rc) goto out_unlock; /* Check the validity of the context. */ if (!policydb_context_isvalid(policydb, &newcontext)) { rc = compute_sid_handle_invalid_context(policy, sentry, tentry, tclass, &newcontext); if (rc) goto out_unlock; } /* Obtain the sid for the context. */ rc = sidtab_context_to_sid(sidtab, &newcontext, out_sid); if (rc == -ESTALE) { rcu_read_unlock(); context_destroy(&newcontext); goto retry; } out_unlock: rcu_read_unlock(); context_destroy(&newcontext); out: return rc; } /** * security_transition_sid - Compute the SID for a new subject/object. * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class * @qstr: object name * @out_sid: security identifier for new subject/object * * Compute a SID to use for labeling a new subject or object in the * class @tclass based on a SID pair (@ssid, @tsid). * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM * if insufficient memory is available, or %0 if the new SID was * computed successfully. */ 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, objname, out_sid, false); } /** * security_member_sid - Compute the SID for member selection. * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class * @out_sid: security identifier for selected member * * Compute a SID to use when selecting a member of a polyinstantiated * object of class @tclass based on a SID pair (@ssid, @tsid). * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM * if insufficient memory is available, or %0 if the SID was * computed successfully. */ int security_member_sid(u32 ssid, u32 tsid, u16 tclass, u32 *out_sid) { return security_compute_sid(ssid, tsid, tclass, AVTAB_MEMBER, NULL, out_sid, false); } /** * security_change_sid - Compute the SID for object relabeling. * @ssid: source security identifier * @tsid: target security identifier * @tclass: target security class * @out_sid: security identifier for selected member * * Compute a SID to use for relabeling an object of class @tclass * based on a SID pair (@ssid, @tsid). * Return -%EINVAL if any of the parameters are invalid, -%ENOMEM * if insufficient memory is available, or %0 if the SID was * computed successfully. */ int security_change_sid(u32 ssid, u32 tsid, u16 tclass, u32 *out_sid) { return security_compute_sid(ssid, tsid, tclass, AVTAB_CHANGE, NULL, out_sid, false); } static inline int convert_context_handle_invalid_context( struct policydb *policydb, struct context *context) { char *s; u32 len; if (enforcing_enabled()) return -EINVAL; if (!context_struct_to_string(policydb, context, &s, &len)) { pr_warn("SELinux: Context %s would be invalid if enforcing\n", s); kfree(s); } return 0; } /** * services_convert_context - Convert a security context across policies. * @args: populated convert_context_args struct * @oldc: original context * @newc: converted context * @gfp_flags: allocation flags * * Convert the values in the security context structure @oldc from the values * specified in the policy @args->oldp to the values specified in the policy * @args->newp, storing the new context in @newc, and verifying that the * context is valid under the new policy. */ int services_convert_context(struct convert_context_args *args, struct context *oldc, struct context *newc, gfp_t gfp_flags) { struct ocontext *oc; struct role_datum *role; struct type_datum *typdatum; struct user_datum *usrdatum; char *s; u32 len; int rc; if (oldc->str) { s = kstrdup(oldc->str, gfp_flags); if (!s) return -ENOMEM; rc = string_to_context_struct(args->newp, NULL, s, newc, SECSID_NULL); if (rc == -EINVAL) { /* * Retain string representation for later mapping. * * IMPORTANT: We need to copy the contents of oldc->str * back into s again because string_to_context_struct() * may have garbled it. */ memcpy(s, oldc->str, oldc->len); context_init(newc); newc->str = s; newc->len = oldc->len; return 0; } kfree(s); if (rc) { /* Other error condition, e.g. ENOMEM. */ pr_err("SELinux: Unable to map context %s, rc = %d.\n", oldc->str, -rc); return rc; } pr_info("SELinux: Context %s became valid (mapped).\n", oldc->str); return 0; } context_init(newc); /* Convert the user. */ usrdatum = symtab_search(&args->newp->p_users, sym_name(args->oldp, SYM_USERS, oldc->user - 1)); if (!usrdatum) goto bad; newc->user = usrdatum->value; /* Convert the role. */ role = symtab_search(&args->newp->p_roles, sym_name(args->oldp, SYM_ROLES, oldc->role - 1)); if (!role) goto bad; newc->role = role->value; /* Convert the type. */ typdatum = symtab_search(&args->newp->p_types, sym_name(args->oldp, SYM_TYPES, oldc->type - 1)); if (!typdatum) goto bad; newc->type = typdatum->value; /* 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, oldc, newc); if (rc) goto bad; } 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; if (!oc) { pr_err("SELinux: unable to look up" " the initial SIDs list\n"); goto bad; } rc = mls_range_set(newc, &oc->context[0].range); if (rc) goto bad; } /* Check the validity of the new context. */ if (!policydb_context_isvalid(args->newp, newc)) { rc = convert_context_handle_invalid_context(args->oldp, oldc); if (rc) goto bad; } return 0; bad: /* Map old representation to string and save it. */ rc = context_struct_to_string(args->oldp, oldc, &s, &len); if (rc) return rc; context_destroy(newc); newc->str = s; newc->len = len; pr_info("SELinux: Context %s became invalid (unmapped).\n", newc->str); return 0; } static void security_load_policycaps(struct selinux_policy *policy) { struct policydb *p; unsigned int i; struct ebitmap_node *node; p = &policy->policydb; for (i = 0; i < ARRAY_SIZE(selinux_state.policycap); i++) WRITE_ONCE(selinux_state.policycap[i], ebitmap_get_bit(&p->policycaps, i)); for (i = 0; i < ARRAY_SIZE(selinux_policycap_names); i++) pr_info("SELinux: policy capability %s=%d\n", selinux_policycap_names[i], ebitmap_get_bit(&p->policycaps, i)); ebitmap_for_each_positive_bit(&p->policycaps, node, i) { if (i >= ARRAY_SIZE(selinux_policycap_names)) pr_info("SELinux: unknown policy capability %u\n", i); } } static int security_preserve_bools(struct selinux_policy *oldpolicy, struct selinux_policy *newpolicy); static void selinux_policy_free(struct selinux_policy *policy) { if (!policy) return; sidtab_destroy(policy->sidtab); kfree(policy->map.mapping); policydb_destroy(&policy->policydb); kfree(policy->sidtab); kfree(policy); } static void selinux_policy_cond_free(struct selinux_policy *policy) { cond_policydb_destroy_dup(&policy->policydb); kfree(policy); } void selinux_policy_cancel(struct selinux_load_state *load_state) { struct selinux_state *state = &selinux_state; struct selinux_policy *oldpolicy; oldpolicy = rcu_dereference_protected(state->policy, lockdep_is_held(&state->policy_mutex)); sidtab_cancel_convert(oldpolicy->sidtab); selinux_policy_free(load_state->policy); kfree(load_state->convert_data); } static void selinux_notify_policy_change(u32 seqno) { /* Flush external caches and notify userspace of policy load */ avc_ss_reset(seqno); selnl_notify_policyload(seqno); selinux_status_update_policyload(seqno); selinux_netlbl_cache_invalidate(); selinux_xfrm_notify_policyload(); selinux_ima_measure_state_locked(); } void selinux_policy_commit(struct selinux_load_state *load_state) { struct selinux_state *state = &selinux_state; struct selinux_policy *oldpolicy, *newpolicy = load_state->policy; unsigned long flags; u32 seqno; oldpolicy = rcu_dereference_protected(state->policy, lockdep_is_held(&state->policy_mutex)); /* If switching between different policy types, log MLS status */ if (oldpolicy) { if (oldpolicy->policydb.mls_enabled && !newpolicy->policydb.mls_enabled) pr_info("SELinux: Disabling MLS support...\n"); else if (!oldpolicy->policydb.mls_enabled && newpolicy->policydb.mls_enabled) pr_info("SELinux: Enabling MLS support...\n"); } /* Set latest granting seqno for new policy. */ if (oldpolicy) newpolicy->latest_granting = oldpolicy->latest_granting + 1; else newpolicy->latest_granting = 1; seqno = newpolicy->latest_granting; /* Install the new policy. */ if (oldpolicy) { sidtab_freeze_begin(oldpolicy->sidtab, &flags); rcu_assign_pointer(state->policy, newpolicy); sidtab_freeze_end(oldpolicy->sidtab, &flags); } else { rcu_assign_pointer(state->policy, newpolicy); } /* Load the policycaps from the new policy */ security_load_policycaps(newpolicy); if (!selinux_initialized()) { /* * After first policy load, the security server is * marked as initialized and ready to handle requests and * any objects created prior to policy load are then labeled. */ selinux_mark_initialized(); selinux_complete_init(); } /* Free the old policy */ synchronize_rcu(); selinux_policy_free(oldpolicy); kfree(load_state->convert_data); /* Notify others of the policy change */ selinux_notify_policy_change(seqno); } /** * security_load_policy - Load a security policy configuration. * @data: binary policy data * @len: length of data in bytes * @load_state: policy load state * * Load a new set of security policy configuration data, * validate it and convert the SID table as necessary. * This function will flush the access vector cache after * loading the new policy. */ int security_load_policy(void *data, size_t len, struct selinux_load_state *load_state) { struct selinux_state *state = &selinux_state; struct selinux_policy *newpolicy, *oldpolicy; struct selinux_policy_convert_data *convert_data; int rc = 0; struct policy_file file = { data, len }, *fp = &file; newpolicy = kzalloc(sizeof(*newpolicy), GFP_KERNEL); if (!newpolicy) return -ENOMEM; newpolicy->sidtab = kzalloc(sizeof(*newpolicy->sidtab), GFP_KERNEL); if (!newpolicy->sidtab) { rc = -ENOMEM; goto err_policy; } rc = policydb_read(&newpolicy->policydb, fp); if (rc) goto err_sidtab; newpolicy->policydb.len = len; rc = selinux_set_mapping(&newpolicy->policydb, secclass_map, &newpolicy->map); if (rc) goto err_policydb; rc = policydb_load_isids(&newpolicy->policydb, newpolicy->sidtab); if (rc) { pr_err("SELinux: unable to load the initial SIDs\n"); goto err_mapping; } if (!selinux_initialized()) { /* First policy load, so no need to preserve state from old policy */ load_state->policy = newpolicy; load_state->convert_data = NULL; return 0; } oldpolicy = rcu_dereference_protected(state->policy, lockdep_is_held(&state->policy_mutex)); /* Preserve active boolean values from the old policy */ rc = security_preserve_bools(oldpolicy, newpolicy); if (rc) { pr_err("SELinux: unable to preserve booleans\n"); goto err_free_isids; } /* * Convert the internal representations of contexts * in the new SID table. */ convert_data = kmalloc(sizeof(*convert_data), GFP_KERNEL); if (!convert_data) { rc = -ENOMEM; goto err_free_isids; } convert_data->args.oldp = &oldpolicy->policydb; convert_data->args.newp = &newpolicy->policydb; convert_data->sidtab_params.args = &convert_data->args; convert_data->sidtab_params.target = newpolicy->sidtab; rc = sidtab_convert(oldpolicy->sidtab, &convert_data->sidtab_params); if (rc) { pr_err("SELinux: unable to convert the internal" " representation of contexts in the new SID" " table\n"); goto err_free_convert_data; } load_state->policy = newpolicy; load_state->convert_data = convert_data; return 0; err_free_convert_data: kfree(convert_data); err_free_isids: sidtab_destroy(newpolicy->sidtab); err_mapping: kfree(newpolicy->map.mapping); err_policydb: policydb_destroy(&newpolicy->policydb); err_sidtab: kfree(newpolicy->sidtab); err_policy: kfree(newpolicy); return rc; } /** * ocontext_to_sid - Helper to safely get sid for an ocontext * @sidtab: SID table * @c: ocontext structure * @index: index of the context entry (0 or 1) * @out_sid: pointer to the resulting SID value * * For all ocontexts except OCON_ISID the SID fields are populated * on-demand when needed. Since updating the SID value is an SMP-sensitive * operation, this helper must be used to do that safely. * * WARNING: This function may return -ESTALE, indicating that the caller * must retry the operation after re-acquiring the policy pointer! */ static int ocontext_to_sid(struct sidtab *sidtab, struct ocontext *c, size_t index, u32 *out_sid) { int rc; u32 sid; /* Ensure the associated sidtab entry is visible to this thread. */ sid = smp_load_acquire(&c->sid[index]); if (!sid) { rc = sidtab_context_to_sid(sidtab, &c->context[index], &sid); if (rc) return rc; /* * Ensure the new sidtab entry is visible to other threads * when they see the SID. */ smp_store_release(&c->sid[index], sid); } *out_sid = sid; return 0; } /** * security_port_sid - Obtain the SID for a port. * @protocol: protocol number * @port: port number * @out_sid: security identifier */ int security_port_sid(u8 protocol, u16 port, u32 *out_sid) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct ocontext *c; int rc; if (!selinux_initialized()) { *out_sid = SECINITSID_PORT; return 0; } retry: rc = 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; c = policydb->ocontexts[OCON_PORT]; while (c) { if (c->u.port.protocol == protocol && c->u.port.low_port <= port && c->u.port.high_port >= port) break; c = c->next; } if (c) { rc = ocontext_to_sid(sidtab, c, 0, out_sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) goto out; } else { *out_sid = SECINITSID_PORT; } out: rcu_read_unlock(); return rc; } /** * security_ib_pkey_sid - Obtain the SID for a pkey. * @subnet_prefix: Subnet Prefix * @pkey_num: pkey number * @out_sid: security identifier */ int security_ib_pkey_sid(u64 subnet_prefix, u16 pkey_num, u32 *out_sid) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct ocontext *c; int rc; if (!selinux_initialized()) { *out_sid = SECINITSID_UNLABELED; return 0; } retry: rc = 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; c = policydb->ocontexts[OCON_IBPKEY]; while (c) { if (c->u.ibpkey.low_pkey <= pkey_num && c->u.ibpkey.high_pkey >= pkey_num && c->u.ibpkey.subnet_prefix == subnet_prefix) break; c = c->next; } if (c) { rc = ocontext_to_sid(sidtab, c, 0, out_sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) goto out; } else *out_sid = SECINITSID_UNLABELED; out: rcu_read_unlock(); return rc; } /** * security_ib_endport_sid - Obtain the SID for a subnet management interface. * @dev_name: device name * @port_num: port number * @out_sid: security identifier */ int security_ib_endport_sid(const char *dev_name, u8 port_num, u32 *out_sid) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct ocontext *c; int rc; if (!selinux_initialized()) { *out_sid = SECINITSID_UNLABELED; return 0; } retry: rc = 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; c = policydb->ocontexts[OCON_IBENDPORT]; while (c) { if (c->u.ibendport.port == port_num && !strncmp(c->u.ibendport.dev_name, dev_name, IB_DEVICE_NAME_MAX)) break; c = c->next; } if (c) { rc = ocontext_to_sid(sidtab, c, 0, out_sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) goto out; } else *out_sid = SECINITSID_UNLABELED; out: rcu_read_unlock(); return rc; } /** * security_netif_sid - Obtain the SID for a network interface. * @name: interface name * @if_sid: interface SID */ int security_netif_sid(char *name, u32 *if_sid) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; int rc; struct ocontext *c; if (!selinux_initialized()) { *if_sid = SECINITSID_NETIF; return 0; } retry: rc = 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; c = policydb->ocontexts[OCON_NETIF]; while (c) { if (strcmp(name, c->u.name) == 0) break; c = c->next; } if (c) { rc = ocontext_to_sid(sidtab, c, 0, if_sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) goto out; } else *if_sid = SECINITSID_NETIF; out: rcu_read_unlock(); return rc; } 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])) { fail = 1; break; } return !fail; } /** * security_node_sid - Obtain the SID for a node (host). * @domain: communication domain aka address family * @addrp: address * @addrlen: address length in bytes * @out_sid: security identifier */ int security_node_sid(u16 domain, void *addrp, u32 addrlen, u32 *out_sid) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; int rc; struct ocontext *c; if (!selinux_initialized()) { *out_sid = SECINITSID_NODE; return 0; } retry: rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; switch (domain) { case AF_INET: { u32 addr; rc = -EINVAL; if (addrlen != sizeof(u32)) goto out; addr = *((u32 *)addrp); c = policydb->ocontexts[OCON_NODE]; while (c) { if (c->u.node.addr == (addr & c->u.node.mask)) break; c = c->next; } break; } case AF_INET6: 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, c->u.node6.mask)) break; c = c->next; } break; default: rc = 0; *out_sid = SECINITSID_NODE; goto out; } if (c) { rc = ocontext_to_sid(sidtab, c, 0, out_sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) goto out; } else { *out_sid = SECINITSID_NODE; } rc = 0; out: rcu_read_unlock(); return rc; } #define SIDS_NEL 25 /** * security_get_user_sids - Obtain reachable SIDs for a user. * @fromsid: starting SID * @username: username * @sids: array of reachable SIDs for user * @nel: number of elements in @sids * * Generate the set of SIDs for legal security contexts * for a given user that can be reached by @fromsid. * Set *@sids to point to a dynamically allocated * array containing the set of SIDs. Set *@nel to the * number of elements in the array. */ int security_get_user_sids(u32 fromsid, char *username, u32 **sids, u32 *nel) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct context *fromcon, usercon; u32 *mysids = NULL, *mysids2, sid; u32 i, j, mynel, maxnel = SIDS_NEL; struct user_datum *user; struct role_datum *role; struct ebitmap_node *rnode, *tnode; int rc; *sids = NULL; *nel = 0; if (!selinux_initialized()) return 0; mysids = kcalloc(maxnel, sizeof(*mysids), GFP_KERNEL); if (!mysids) return -ENOMEM; retry: mynel = 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; context_init(&usercon); rc = -EINVAL; fromcon = sidtab_search(sidtab, fromsid); if (!fromcon) goto out_unlock; rc = -EINVAL; user = symtab_search(&policydb->p_users, username); if (!user) goto out_unlock; usercon.user = user->value; ebitmap_for_each_positive_bit(&user->roles, rnode, i) { role = policydb->role_val_to_struct[i]; usercon.role = i + 1; ebitmap_for_each_positive_bit(&role->types, tnode, j) { usercon.type = j + 1; if (mls_setup_user_range(policydb, fromcon, user, &usercon)) continue; rc = sidtab_context_to_sid(sidtab, &usercon, &sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } 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) goto out_unlock; memcpy(mysids2, mysids, mynel * sizeof(*mysids2)); kfree(mysids); mysids = mysids2; mysids[mynel++] = sid; } } } rc = 0; out_unlock: rcu_read_unlock(); if (rc || !mynel) { kfree(mysids); return rc; } rc = -ENOMEM; mysids2 = kcalloc(mynel, sizeof(*mysids2), GFP_KERNEL); if (!mysids2) { kfree(mysids); return rc; } 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(); } kfree(mysids); *sids = mysids2; *nel = j; return 0; } /** * __security_genfs_sid - Helper to obtain a SID for a file in a filesystem * @policy: policy * @fstype: filesystem type * @path: path from root of mount * @orig_sclass: file security class * @sid: SID for path * * Obtain a SID to use for a file in a filesystem that * cannot support xattr or use a fixed labeling behavior like * transition SIDs or task SIDs. * * WARNING: This function may return -ESTALE, indicating that the caller * must retry the operation after re-acquiring the policy pointer! */ static inline int __security_genfs_sid(struct selinux_policy *policy, const char *fstype, const char *path, u16 orig_sclass, u32 *sid) { struct policydb *policydb = &policy->policydb; struct sidtab *sidtab = policy->sidtab; u16 sclass; struct genfs *genfs; struct ocontext *c; int cmp = 0; while (path[0] == '/' && path[1] == '/') path++; sclass = unmap_class(&policy->map, orig_sclass); *sid = SECINITSID_UNLABELED; for (genfs = policydb->genfs; genfs; genfs = genfs->next) { cmp = strcmp(fstype, genfs->fstype); if (cmp <= 0) break; } if (!genfs || cmp) return -ENOENT; for (c = genfs->head; c; c = c->next) { size_t len = strlen(c->u.name); if ((!c->v.sclass || sclass == c->v.sclass) && (strncmp(c->u.name, path, len) == 0)) break; } if (!c) return -ENOENT; return ocontext_to_sid(sidtab, c, 0, sid); } /** * security_genfs_sid - Obtain a SID for a file in a filesystem * @fstype: filesystem type * @path: path from root of mount * @orig_sclass: file security class * @sid: SID for path * * Acquire policy_rwlock before calling __security_genfs_sid() and release * it afterward. */ int security_genfs_sid(const char *fstype, const char *path, u16 orig_sclass, u32 *sid) { struct selinux_policy *policy; int retval; if (!selinux_initialized()) { *sid = SECINITSID_UNLABELED; return 0; } do { rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); retval = __security_genfs_sid(policy, fstype, path, orig_sclass, sid); rcu_read_unlock(); } while (retval == -ESTALE); return retval; } int selinux_policy_genfs_sid(struct selinux_policy *policy, const char *fstype, const char *path, u16 orig_sclass, u32 *sid) { /* no lock required, policy is not yet accessible by other threads */ return __security_genfs_sid(policy, fstype, path, orig_sclass, sid); } /** * security_fs_use - Determine how to handle labeling for a filesystem. * @sb: superblock in question */ int security_fs_use(struct super_block *sb) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; int rc; struct ocontext *c; struct superblock_security_struct *sbsec = selinux_superblock(sb); const char *fstype = sb->s_type->name; if (!selinux_initialized()) { sbsec->behavior = SECURITY_FS_USE_NONE; sbsec->sid = SECINITSID_UNLABELED; return 0; } retry: rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; c = policydb->ocontexts[OCON_FSUSE]; while (c) { if (strcmp(fstype, c->u.name) == 0) break; c = c->next; } if (c) { sbsec->behavior = c->v.behavior; rc = ocontext_to_sid(sidtab, c, 0, &sbsec->sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) goto out; } else { rc = __security_genfs_sid(policy, fstype, "/", SECCLASS_DIR, &sbsec->sid); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) { sbsec->behavior = SECURITY_FS_USE_NONE; rc = 0; } else { sbsec->behavior = SECURITY_FS_USE_GENFS; } } out: rcu_read_unlock(); return rc; } int security_get_bools(struct selinux_policy *policy, u32 *len, char ***names, int **values) { struct policydb *policydb; u32 i; int rc; policydb = &policy->policydb; *names = NULL; *values = NULL; rc = 0; *len = policydb->p_bools.nprim; if (!*len) goto out; rc = -ENOMEM; *names = kcalloc(*len, sizeof(char *), GFP_ATOMIC); if (!*names) goto err; rc = -ENOMEM; *values = kcalloc(*len, sizeof(int), GFP_ATOMIC); if (!*values) goto err; for (i = 0; i < *len; i++) { (*values)[i] = policydb->bool_val_to_struct[i]->state; rc = -ENOMEM; (*names)[i] = kstrdup(sym_name(policydb, SYM_BOOLS, i), GFP_ATOMIC); if (!(*names)[i]) goto err; } rc = 0; out: return rc; err: if (*names) { for (i = 0; i < *len; i++) kfree((*names)[i]); kfree(*names); } kfree(*values); *len = 0; *names = NULL; *values = NULL; goto out; } int security_set_bools(u32 len, int *values) { struct selinux_state *state = &selinux_state; struct selinux_policy *newpolicy, *oldpolicy; int rc; u32 i, seqno = 0; if (!selinux_initialized()) return -EINVAL; oldpolicy = rcu_dereference_protected(state->policy, lockdep_is_held(&state->policy_mutex)); /* Consistency check on number of booleans, should never fail */ if (WARN_ON(len != oldpolicy->policydb.p_bools.nprim)) return -EINVAL; newpolicy = kmemdup(oldpolicy, sizeof(*newpolicy), GFP_KERNEL); if (!newpolicy) return -ENOMEM; /* * Deep copy only the parts of the policydb that might be * modified as a result of changing booleans. */ rc = cond_policydb_dup(&newpolicy->policydb, &oldpolicy->policydb); if (rc) { kfree(newpolicy); return -ENOMEM; } /* Update the boolean states in the copy */ for (i = 0; i < len; i++) { int new_state = !!values[i]; int old_state = newpolicy->policydb.bool_val_to_struct[i]->state; if (new_state != old_state) { audit_log(audit_context(), GFP_ATOMIC, AUDIT_MAC_CONFIG_CHANGE, "bool=%s val=%d old_val=%d auid=%u ses=%u", sym_name(&newpolicy->policydb, SYM_BOOLS, i), new_state, old_state, from_kuid(&init_user_ns, audit_get_loginuid(current)), audit_get_sessionid(current)); newpolicy->policydb.bool_val_to_struct[i]->state = new_state; } } /* Re-evaluate the conditional rules in the copy */ evaluate_cond_nodes(&newpolicy->policydb); /* Set latest granting seqno for new policy */ newpolicy->latest_granting = oldpolicy->latest_granting + 1; seqno = newpolicy->latest_granting; /* Install the new policy */ rcu_assign_pointer(state->policy, newpolicy); /* * Free the conditional portions of the old policydb * that were copied for the new policy, and the oldpolicy * structure itself but not what it references. */ synchronize_rcu(); selinux_policy_cond_free(oldpolicy); /* Notify others of the policy change */ selinux_notify_policy_change(seqno); return 0; } int security_get_bool_value(u32 index) { struct selinux_policy *policy; struct policydb *policydb; int rc; u32 len; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; rc = -EFAULT; len = policydb->p_bools.nprim; if (index >= len) goto out; rc = policydb->bool_val_to_struct[index]->state; out: rcu_read_unlock(); return rc; } static int security_preserve_bools(struct selinux_policy *oldpolicy, struct selinux_policy *newpolicy) { int rc, *bvalues = NULL; char **bnames = NULL; struct cond_bool_datum *booldatum; u32 i, nbools = 0; rc = security_get_bools(oldpolicy, &nbools, &bnames, &bvalues); if (rc) goto out; for (i = 0; i < nbools; i++) { booldatum = symtab_search(&newpolicy->policydb.p_bools, bnames[i]); if (booldatum) booldatum->state = bvalues[i]; } evaluate_cond_nodes(&newpolicy->policydb); 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 selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; struct context *context1; struct context *context2; struct context newcon; char *s; u32 len; int rc; if (!selinux_initialized()) { *new_sid = sid; return 0; } retry: rc = 0; context_init(&newcon); rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; if (!policydb->mls_enabled) { *new_sid = sid; goto out_unlock; } rc = -EINVAL; context1 = sidtab_search(sidtab, sid); if (!context1) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, sid); goto out_unlock; } rc = -EINVAL; context2 = sidtab_search(sidtab, mls_sid); if (!context2) { pr_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(policydb, &newcon); if (rc) { if (!context_struct_to_string(policydb, &newcon, &s, &len)) { struct audit_buffer *ab; ab = audit_log_start(audit_context(), GFP_ATOMIC, AUDIT_SELINUX_ERR); audit_log_format(ab, "op=security_sid_mls_copy invalid_context="); /* don't record NUL with untrusted strings */ audit_log_n_untrustedstring(ab, s, len - 1); audit_log_end(ab); kfree(s); } goto out_unlock; } } rc = sidtab_context_to_sid(sidtab, &newcon, new_sid); if (rc == -ESTALE) { rcu_read_unlock(); context_destroy(&newcon); goto retry; } out_unlock: rcu_read_unlock(); context_destroy(&newcon); 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 * @peer_sid: network peer 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) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; 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; } if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; /* * We don't need to check 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 state->initialized was true. */ if (!policydb->mls_enabled) { rc = 0; goto out; } rc = -EINVAL; nlbl_ctx = sidtab_search(sidtab, nlbl_sid); if (!nlbl_ctx) { pr_err("SELinux: %s: unrecognized SID %d\n", __func__, nlbl_sid); goto out; } rc = -EINVAL; xfrm_ctx = sidtab_search(sidtab, xfrm_sid); if (!xfrm_ctx) { pr_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: rcu_read_unlock(); return rc; } static int get_classes_callback(void *k, void *d, void *args) { struct class_datum *datum = d; char *name = k, **classes = args; u32 value = datum->value - 1; classes[value] = kstrdup(name, GFP_ATOMIC); if (!classes[value]) return -ENOMEM; return 0; } int security_get_classes(struct selinux_policy *policy, char ***classes, u32 *nclasses) { struct policydb *policydb; int rc; policydb = &policy->policydb; 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) { u32 i; for (i = 0; i < *nclasses; i++) kfree((*classes)[i]); kfree(*classes); } out: return rc; } static int get_permissions_callback(void *k, void *d, void *args) { struct perm_datum *datum = d; char *name = k, **perms = args; u32 value = datum->value - 1; perms[value] = kstrdup(name, GFP_ATOMIC); if (!perms[value]) return -ENOMEM; return 0; } int security_get_permissions(struct selinux_policy *policy, const char *class, char ***perms, u32 *nperms) { struct policydb *policydb; u32 i; int rc; struct class_datum *match; policydb = &policy->policydb; rc = -EINVAL; match = symtab_search(&policydb->p_classes, class); if (!match) { pr_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: return rc; err: for (i = 0; i < *nperms; i++) kfree((*perms)[i]); kfree(*perms); return rc; } int security_get_reject_unknown(void) { struct selinux_policy *policy; int value; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); value = policy->policydb.reject_unknown; rcu_read_unlock(); return value; } int security_get_allow_unknown(void) { struct selinux_policy *policy; int value; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); value = policy->policydb.allow_unknown; rcu_read_unlock(); return value; } /** * 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) { struct selinux_policy *policy; int rc; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); rc = ebitmap_get_bit(&policy->policydb.policycaps, req_cap); rcu_read_unlock(); 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_state *state = &selinux_state; struct selinux_policy *policy; struct policydb *policydb; 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 (!selinux_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); rcu_read_lock(); policy = rcu_dereference(state->policy); policydb = &policy->policydb; tmprule->au_seqno = policy->latest_granting; switch (field) { case AUDIT_SUBJ_USER: case AUDIT_OBJ_USER: userdatum = symtab_search(&policydb->p_users, rulestr); if (!userdatum) { rc = -EINVAL; goto err; } tmprule->au_ctxt.user = userdatum->value; break; case AUDIT_SUBJ_ROLE: case AUDIT_OBJ_ROLE: roledatum = symtab_search(&policydb->p_roles, rulestr); if (!roledatum) { rc = -EINVAL; goto err; } tmprule->au_ctxt.role = roledatum->value; break; case AUDIT_SUBJ_TYPE: case AUDIT_OBJ_TYPE: typedatum = symtab_search(&policydb->p_types, rulestr); if (!typedatum) { rc = -EINVAL; goto err; } 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(policydb, rulestr, &tmprule->au_ctxt, GFP_ATOMIC); if (rc) goto err; break; } rcu_read_unlock(); *rule = tmprule; return 0; err: rcu_read_unlock(); selinux_audit_rule_free(tmprule); *rule = NULL; return rc; } /* Check to see if the rule contains any selinux fields */ int selinux_audit_rule_known(struct audit_krule *rule) { u32 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 selinux_state *state = &selinux_state; struct selinux_policy *policy; 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; } if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(state->policy); if (rule->au_seqno < policy->latest_granting) { match = -ESTALE; goto out; } ctxt = sidtab_search(policy->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: rcu_read_unlock(); return match; } static int aurule_avc_callback(u32 event) { if (event == AVC_CALLBACK_RESET) return audit_update_lsm_rules(); return 0; } 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) { struct selinux_policy *policy; struct policydb *policydb; struct sidtab *sidtab; int rc; struct context *ctx; struct context ctx_new; if (!selinux_initialized()) { *sid = SECSID_NULL; return 0; } retry: rc = 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; sidtab = policy->sidtab; 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(policydb, &ctx_new, secattr); if (secattr->flags & NETLBL_SECATTR_MLS_CAT) { rc = mls_import_netlbl_cat(policydb, &ctx_new, secattr); if (rc) goto out; } rc = -EIDRM; if (!mls_context_isvalid(policydb, &ctx_new)) { ebitmap_destroy(&ctx_new.range.level[0].cat); goto out; } rc = sidtab_context_to_sid(sidtab, &ctx_new, sid); ebitmap_destroy(&ctx_new.range.level[0].cat); if (rc == -ESTALE) { rcu_read_unlock(); goto retry; } if (rc) goto out; security_netlbl_cache_add(secattr, *sid); } else *sid = SECSID_NULL; out: rcu_read_unlock(); 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) { struct selinux_policy *policy; struct policydb *policydb; int rc; struct context *ctx; if (!selinux_initialized()) return 0; rcu_read_lock(); policy = rcu_dereference(selinux_state.policy); policydb = &policy->policydb; rc = -ENOENT; ctx = sidtab_search(policy->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(policydb, ctx, secattr); rc = mls_export_netlbl_cat(policydb, ctx, secattr); out: rcu_read_unlock(); return rc; } #endif /* CONFIG_NETLABEL */ /** * __security_read_policy - read the policy. * @policy: SELinux policy * @data: binary policy data * @len: length of data in bytes * */ static int __security_read_policy(struct selinux_policy *policy, void *data, size_t *len) { int rc; struct policy_file fp; fp.data = data; fp.len = *len; rc = policydb_write(&policy->policydb, &fp); if (rc) return rc; *len = (unsigned long)fp.data - (unsigned long)data; return 0; } /** * 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) { struct selinux_state *state = &selinux_state; struct selinux_policy *policy; policy = rcu_dereference_protected( state->policy, lockdep_is_held(&state->policy_mutex)); if (!policy) return -EINVAL; *len = policy->policydb.len; *data = vmalloc_user(*len); if (!*data) return -ENOMEM; return __security_read_policy(policy, *data, len); } /** * security_read_state_kernel - read the policy. * @data: binary policy data * @len: length of data in bytes * * Allocates kernel memory for reading SELinux policy. * This function is for internal use only and should not * be used for returning data to user space. * * This function must be called with policy_mutex held. */ int security_read_state_kernel(void **data, size_t *len) { int err; struct selinux_state *state = &selinux_state; struct selinux_policy *policy; policy = rcu_dereference_protected( state->policy, lockdep_is_held(&state->policy_mutex)); if (!policy) return -EINVAL; *len = policy->policydb.len; *data = vmalloc(*len); if (!*data) return -ENOMEM; err = __security_read_policy(policy, *data, len); if (err) { vfree(*data); *data = NULL; *len = 0; } return err; }
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