/* * Cryptographic API for algorithms (i.e., low-level API). * * Copyright (c) 2006 Herbert Xu <herbert@gondor.apana.org.au> * * This program is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License as published by the Free * Software Foundation; either version 2 of the License, or (at your option) * any later version. * */ #include <linux/err.h> #include <linux/errno.h> #include <linux/init.h> #include <linux/kernel.h> #include <linux/list.h> #include <linux/module.h> #include <linux/rtnetlink.h> #include <linux/string.h> #include "internal.h" static void crypto_remove_final(struct list_head *list); static LIST_HEAD(crypto_template_list); void crypto_larval_error(const char *name, u32 type, u32 mask) { struct crypto_alg *alg; alg = crypto_alg_lookup(name, type, mask); if (alg) { if (crypto_is_larval(alg)) { struct crypto_larval *larval = (void *)alg; complete_all(&larval->completion); } crypto_mod_put(alg); } } EXPORT_SYMBOL_GPL(crypto_larval_error); static inline int crypto_set_driver_name(struct crypto_alg *alg) { static const char suffix[] = "-generic"; char *driver_name = alg->cra_driver_name; int len; if (*driver_name) return 0; len = strlcpy(driver_name, alg->cra_name, CRYPTO_MAX_ALG_NAME); if (len + sizeof(suffix) > CRYPTO_MAX_ALG_NAME) return -ENAMETOOLONG; memcpy(driver_name + len, suffix, sizeof(suffix)); return 0; } static int crypto_check_alg(struct crypto_alg *alg) { if (alg->cra_alignmask & (alg->cra_alignmask + 1)) return -EINVAL; if (alg->cra_blocksize > PAGE_SIZE / 8) return -EINVAL; if (alg->cra_priority < 0) return -EINVAL; return crypto_set_driver_name(alg); } static void crypto_destroy_instance(struct crypto_alg *alg) { struct crypto_instance *inst = (void *)alg; struct crypto_template *tmpl = inst->tmpl; tmpl->free(inst); crypto_tmpl_put(tmpl); } static void crypto_remove_spawn(struct crypto_spawn *spawn, struct list_head *list, struct list_head *secondary_spawns) { struct crypto_instance *inst = spawn->inst; struct crypto_template *tmpl = inst->tmpl; list_del_init(&spawn->list); spawn->alg = NULL; if (crypto_is_dead(&inst->alg)) return; inst->alg.cra_flags |= CRYPTO_ALG_DEAD; if (hlist_unhashed(&inst->list)) return; if (!tmpl || !crypto_tmpl_get(tmpl)) return; crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, &inst->alg); list_move(&inst->alg.cra_list, list); hlist_del(&inst->list); inst->alg.cra_destroy = crypto_destroy_instance; list_splice(&inst->alg.cra_users, secondary_spawns); } static void crypto_remove_spawns(struct list_head *spawns, struct list_head *list, u32 new_type) { struct crypto_spawn *spawn, *n; LIST_HEAD(secondary_spawns); list_for_each_entry_safe(spawn, n, spawns, list) { if ((spawn->alg->cra_flags ^ new_type) & spawn->mask) continue; crypto_remove_spawn(spawn, list, &secondary_spawns); } while (!list_empty(&secondary_spawns)) { list_for_each_entry_safe(spawn, n, &secondary_spawns, list) crypto_remove_spawn(spawn, list, &secondary_spawns); } } static struct crypto_larval *__crypto_register_alg(struct crypto_alg *alg) { struct crypto_alg *q; struct crypto_larval *larval; int ret = -EAGAIN; if (crypto_is_dead(alg)) goto err; INIT_LIST_HEAD(&alg->cra_users); /* No cheating! */ alg->cra_flags &= ~CRYPTO_ALG_TESTED; ret = -EEXIST; atomic_set(&alg->cra_refcnt, 1); list_for_each_entry(q, &crypto_alg_list, cra_list) { if (q == alg) goto err; if (crypto_is_larval(q)) { if (!strcmp(alg->cra_driver_name, q->cra_driver_name)) goto err; continue; } if (!strcmp(q->cra_driver_name, alg->cra_name) || !strcmp(q->cra_name, alg->cra_driver_name)) goto err; } larval = crypto_larval_alloc(alg->cra_name, alg->cra_flags | CRYPTO_ALG_TESTED, 0); if (IS_ERR(larval)) goto out; ret = -ENOENT; larval->adult = crypto_mod_get(alg); if (!larval->adult) goto free_larval; atomic_set(&larval->alg.cra_refcnt, 1); memcpy(larval->alg.cra_driver_name, alg->cra_driver_name, CRYPTO_MAX_ALG_NAME); larval->alg.cra_priority = alg->cra_priority; list_add(&alg->cra_list, &crypto_alg_list); list_add(&larval->alg.cra_list, &crypto_alg_list); out: return larval; free_larval: kfree(larval); err: larval = ERR_PTR(ret); goto out; } void crypto_alg_tested(const char *name, int err) { struct crypto_larval *test; struct crypto_alg *alg; struct crypto_alg *q; LIST_HEAD(list); down_write(&crypto_alg_sem); list_for_each_entry(q, &crypto_alg_list, cra_list) { if (!crypto_is_larval(q)) continue; test = (struct crypto_larval *)q; if (!strcmp(q->cra_driver_name, name)) goto found; } printk(KERN_ERR "alg: Unexpected test result for %s: %d\n", name, err); goto unlock; found: alg = test->adult; if (err || list_empty(&alg->cra_list)) goto complete; alg->cra_flags |= CRYPTO_ALG_TESTED; list_for_each_entry(q, &crypto_alg_list, cra_list) { if (q == alg) continue; if (crypto_is_moribund(q)) continue; if (crypto_is_larval(q)) { struct crypto_larval *larval = (void *)q; /* * Check to see if either our generic name or * specific name can satisfy the name requested * by the larval entry q. */ if (strcmp(alg->cra_name, q->cra_name) && strcmp(alg->cra_driver_name, q->cra_name)) continue; if (larval->adult) continue; if ((q->cra_flags ^ alg->cra_flags) & larval->mask) continue; if (!crypto_mod_get(alg)) continue; larval->adult = alg; complete_all(&larval->completion); continue; } if (strcmp(alg->cra_name, q->cra_name)) continue; if (strcmp(alg->cra_driver_name, q->cra_driver_name) && q->cra_priority > alg->cra_priority) continue; crypto_remove_spawns(&q->cra_users, &list, alg->cra_flags); } complete: complete_all(&test->completion); unlock: up_write(&crypto_alg_sem); crypto_remove_final(&list); } EXPORT_SYMBOL_GPL(crypto_alg_tested); static void crypto_remove_final(struct list_head *list) { struct crypto_alg *alg; struct crypto_alg *n; list_for_each_entry_safe(alg, n, list, cra_list) { list_del_init(&alg->cra_list); crypto_alg_put(alg); } } static void crypto_wait_for_test(struct crypto_larval *larval) { int err; err = crypto_probing_notify(CRYPTO_MSG_ALG_REGISTER, larval->adult); if (err != NOTIFY_STOP) { if (WARN_ON(err != NOTIFY_DONE)) goto out; crypto_alg_tested(larval->alg.cra_driver_name, 0); } err = wait_for_completion_interruptible(&larval->completion); WARN_ON(err); out: crypto_larval_kill(&larval->alg); } int crypto_register_alg(struct crypto_alg *alg) { struct crypto_larval *larval; int err; err = crypto_check_alg(alg); if (err) return err; down_write(&crypto_alg_sem); larval = __crypto_register_alg(alg); up_write(&crypto_alg_sem); if (IS_ERR(larval)) return PTR_ERR(larval); crypto_wait_for_test(larval); return 0; } EXPORT_SYMBOL_GPL(crypto_register_alg); static int crypto_remove_alg(struct crypto_alg *alg, struct list_head *list) { if (unlikely(list_empty(&alg->cra_list))) return -ENOENT; alg->cra_flags |= CRYPTO_ALG_DEAD; crypto_notify(CRYPTO_MSG_ALG_UNREGISTER, alg); list_del_init(&alg->cra_list); crypto_remove_spawns(&alg->cra_users, list, alg->cra_flags); return 0; } int crypto_unregister_alg(struct crypto_alg *alg) { int ret; LIST_HEAD(list); down_write(&crypto_alg_sem); ret = crypto_remove_alg(alg, &list); up_write(&crypto_alg_sem); if (ret) return ret; BUG_ON(atomic_read(&alg->cra_refcnt) != 1); if (alg->cra_destroy) alg->cra_destroy(alg); crypto_remove_final(&list); return 0; } EXPORT_SYMBOL_GPL(crypto_unregister_alg); int crypto_register_template(struct crypto_template *tmpl) { struct crypto_template *q; int err = -EEXIST; down_write(&crypto_alg_sem); list_for_each_entry(q, &crypto_template_list, list) { if (q == tmpl) goto out; } list_add(&tmpl->list, &crypto_template_list); crypto_notify(CRYPTO_MSG_TMPL_REGISTER, tmpl); err = 0; out: up_write(&crypto_alg_sem); return err; } EXPORT_SYMBOL_GPL(crypto_register_template); void crypto_unregister_template(struct crypto_template *tmpl) { struct crypto_instance *inst; struct hlist_node *p, *n; struct hlist_head *list; LIST_HEAD(users); down_write(&crypto_alg_sem); BUG_ON(list_empty(&tmpl->list)); list_del_init(&tmpl->list); list = &tmpl->instances; hlist_for_each_entry(inst, p, list, list) { int err = crypto_remove_alg(&inst->alg, &users); BUG_ON(err); } crypto_notify(CRYPTO_MSG_TMPL_UNREGISTER, tmpl); up_write(&crypto_alg_sem); hlist_for_each_entry_safe(inst, p, n, list, list) { BUG_ON(atomic_read(&inst->alg.cra_refcnt) != 1); tmpl->free(inst); } crypto_remove_final(&users); } EXPORT_SYMBOL_GPL(crypto_unregister_template); static struct crypto_template *__crypto_lookup_template(const char *name) { struct crypto_template *q, *tmpl = NULL; down_read(&crypto_alg_sem); list_for_each_entry(q, &crypto_template_list, list) { if (strcmp(q->name, name)) continue; if (unlikely(!crypto_tmpl_get(q))) continue; tmpl = q; break; } up_read(&crypto_alg_sem); return tmpl; } struct crypto_template *crypto_lookup_template(const char *name) { return try_then_request_module(__crypto_lookup_template(name), name); } EXPORT_SYMBOL_GPL(crypto_lookup_template); int crypto_register_instance(struct crypto_template *tmpl, struct crypto_instance *inst) { struct crypto_larval *larval; int err; err = crypto_check_alg(&inst->alg); if (err) goto err; inst->alg.cra_module = tmpl->module; down_write(&crypto_alg_sem); larval = __crypto_register_alg(&inst->alg); if (IS_ERR(larval)) goto unlock; hlist_add_head(&inst->list, &tmpl->instances); inst->tmpl = tmpl; unlock: up_write(&crypto_alg_sem); err = PTR_ERR(larval); if (IS_ERR(larval)) goto err; crypto_wait_for_test(larval); err = 0; err: return err; } EXPORT_SYMBOL_GPL(crypto_register_instance); int crypto_init_spawn(struct crypto_spawn *spawn, struct crypto_alg *alg, struct crypto_instance *inst, u32 mask) { int err = -EAGAIN; spawn->inst = inst; spawn->mask = mask; down_write(&crypto_alg_sem); if (!crypto_is_moribund(alg)) { list_add(&spawn->list, &alg->cra_users); spawn->alg = alg; err = 0; } up_write(&crypto_alg_sem); return err; } EXPORT_SYMBOL_GPL(crypto_init_spawn); void crypto_drop_spawn(struct crypto_spawn *spawn) { down_write(&crypto_alg_sem); list_del(&spawn->list); up_write(&crypto_alg_sem); } EXPORT_SYMBOL_GPL(crypto_drop_spawn); struct crypto_tfm *crypto_spawn_tfm(struct crypto_spawn *spawn, u32 type, u32 mask) { struct crypto_alg *alg; struct crypto_alg *alg2; struct crypto_tfm *tfm; down_read(&crypto_alg_sem); alg = spawn->alg; alg2 = alg; if (alg2) alg2 = crypto_mod_get(alg2); up_read(&crypto_alg_sem); if (!alg2) { if (alg) crypto_shoot_alg(alg); return ERR_PTR(-EAGAIN); } tfm = ERR_PTR(-EINVAL); if (unlikely((alg->cra_flags ^ type) & mask)) goto out_put_alg; tfm = __crypto_alloc_tfm(alg, type, mask); if (IS_ERR(tfm)) goto out_put_alg; return tfm; out_put_alg: crypto_mod_put(alg); return tfm; } EXPORT_SYMBOL_GPL(crypto_spawn_tfm); int crypto_register_notifier(struct notifier_block *nb) { return blocking_notifier_chain_register(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_register_notifier); int crypto_unregister_notifier(struct notifier_block *nb) { return blocking_notifier_chain_unregister(&crypto_chain, nb); } EXPORT_SYMBOL_GPL(crypto_unregister_notifier); struct crypto_attr_type *crypto_get_attr_type(struct rtattr **tb) { struct rtattr *rta = tb[0]; struct crypto_attr_type *algt; if (!rta) return ERR_PTR(-ENOENT); if (RTA_PAYLOAD(rta) < sizeof(*algt)) return ERR_PTR(-EINVAL); if (rta->rta_type != CRYPTOA_TYPE) return ERR_PTR(-EINVAL); algt = RTA_DATA(rta); return algt; } EXPORT_SYMBOL_GPL(crypto_get_attr_type); int crypto_check_attr_type(struct rtattr **tb, u32 type) { struct crypto_attr_type *algt; algt = crypto_get_attr_type(tb); if (IS_ERR(algt)) return PTR_ERR(algt); if ((algt->type ^ type) & algt->mask) return -EINVAL; return 0; } EXPORT_SYMBOL_GPL(crypto_check_attr_type); const char *crypto_attr_alg_name(struct rtattr *rta) { struct crypto_attr_alg *alga; if (!rta) return ERR_PTR(-ENOENT); if (RTA_PAYLOAD(rta) < sizeof(*alga)) return ERR_PTR(-EINVAL); if (rta->rta_type != CRYPTOA_ALG) return ERR_PTR(-EINVAL); alga = RTA_DATA(rta); alga->name[CRYPTO_MAX_ALG_NAME - 1] = 0; return alga->name; } EXPORT_SYMBOL_GPL(crypto_attr_alg_name); struct crypto_alg *crypto_attr_alg(struct rtattr *rta, u32 type, u32 mask) { const char *name; int err; name = crypto_attr_alg_name(rta); err = PTR_ERR(name); if (IS_ERR(name)) return ERR_PTR(err); return crypto_alg_mod_lookup(name, type, mask); } EXPORT_SYMBOL_GPL(crypto_attr_alg); int crypto_attr_u32(struct rtattr *rta, u32 *num) { struct crypto_attr_u32 *nu32; if (!rta) return -ENOENT; if (RTA_PAYLOAD(rta) < sizeof(*nu32)) return -EINVAL; if (rta->rta_type != CRYPTOA_U32) return -EINVAL; nu32 = RTA_DATA(rta); *num = nu32->num; return 0; } EXPORT_SYMBOL_GPL(crypto_attr_u32); struct crypto_instance *crypto_alloc_instance(const char *name, struct crypto_alg *alg) { struct crypto_instance *inst; struct crypto_spawn *spawn; int err; inst = kzalloc(sizeof(*inst) + sizeof(*spawn), GFP_KERNEL); if (!inst) return ERR_PTR(-ENOMEM); err = -ENAMETOOLONG; if (snprintf(inst->alg.cra_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name, alg->cra_name) >= CRYPTO_MAX_ALG_NAME) goto err_free_inst; if (snprintf(inst->alg.cra_driver_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", name, alg->cra_driver_name) >= CRYPTO_MAX_ALG_NAME) goto err_free_inst; spawn = crypto_instance_ctx(inst); err = crypto_init_spawn(spawn, alg, inst, CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_ASYNC); if (err) goto err_free_inst; return inst; err_free_inst: kfree(inst); return ERR_PTR(err); } EXPORT_SYMBOL_GPL(crypto_alloc_instance); void crypto_init_queue(struct crypto_queue *queue, unsigned int max_qlen) { INIT_LIST_HEAD(&queue->list); queue->backlog = &queue->list; queue->qlen = 0; queue->max_qlen = max_qlen; } EXPORT_SYMBOL_GPL(crypto_init_queue); int crypto_enqueue_request(struct crypto_queue *queue, struct crypto_async_request *request) { int err = -EINPROGRESS; if (unlikely(queue->qlen >= queue->max_qlen)) { err = -EBUSY; if (!(request->flags & CRYPTO_TFM_REQ_MAY_BACKLOG)) goto out; if (queue->backlog == &queue->list) queue->backlog = &request->list; } queue->qlen++; list_add_tail(&request->list, &queue->list); out: return err; } EXPORT_SYMBOL_GPL(crypto_enqueue_request); struct crypto_async_request *crypto_dequeue_request(struct crypto_queue *queue) { struct list_head *request; if (unlikely(!queue->qlen)) return NULL; queue->qlen--; if (queue->backlog != &queue->list) queue->backlog = queue->backlog->next; request = queue->list.next; list_del(request); return list_entry(request, struct crypto_async_request, list); } EXPORT_SYMBOL_GPL(crypto_dequeue_request); int crypto_tfm_in_queue(struct crypto_queue *queue, struct crypto_tfm *tfm) { struct crypto_async_request *req; list_for_each_entry(req, &queue->list, list) { if (req->tfm == tfm) return 1; } return 0; } EXPORT_SYMBOL_GPL(crypto_tfm_in_queue); static inline void crypto_inc_byte(u8 *a, unsigned int size) { u8 *b = (a + size); u8 c; for (; size; size--) { c = *--b + 1; *b = c; if (c) break; } } void crypto_inc(u8 *a, unsigned int size) { __be32 *b = (__be32 *)(a + size); u32 c; for (; size >= 4; size -= 4) { c = be32_to_cpu(*--b) + 1; *b = cpu_to_be32(c); if (c) return; } crypto_inc_byte(a, size); } EXPORT_SYMBOL_GPL(crypto_inc); static inline void crypto_xor_byte(u8 *a, const u8 *b, unsigned int size) { for (; size; size--) *a++ ^= *b++; } void crypto_xor(u8 *dst, const u8 *src, unsigned int size) { u32 *a = (u32 *)dst; u32 *b = (u32 *)src; for (; size >= 4; size -= 4) *a++ ^= *b++; crypto_xor_byte((u8 *)a, (u8 *)b, size); } EXPORT_SYMBOL_GPL(crypto_xor); static int __init crypto_algapi_init(void) { crypto_init_proc(); return 0; } static void __exit crypto_algapi_exit(void) { crypto_exit_proc(); } module_init(crypto_algapi_init); module_exit(crypto_algapi_exit); MODULE_LICENSE("GPL"); MODULE_DESCRIPTION("Cryptographic algorithms API");