1 files changed, 516 insertions, 0 deletions
diff --git a/crypto/crypto_user_base.c b/crypto/crypto_user_base.c
new file mode 100644
index 0000000000..3fa20f1298
--- /dev/null
+++ b/crypto/crypto_user_base.c
@@ -0,0 +1,516 @@
+// SPDX-License-Identifier: GPL-2.0-only
+/*
+ * Crypto user configuration API.
+ *
+ * Copyright (C) 2011 secunet Security Networks AG
+ * Copyright (C) 2011 Steffen Klassert <steffen.klassert@secunet.com>
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/cryptouser.h>
+#include <linux/sched.h>
+#include <linux/security.h>
+#include <net/netlink.h>
+#include <net/net_namespace.h>
+#include <net/sock.h>
+#include <crypto/internal/skcipher.h>
+#include <crypto/internal/rng.h>
+#include <crypto/akcipher.h>
+#include <crypto/kpp.h>
+#include <crypto/internal/cryptouser.h>
+
+#include "internal.h"
+
+#define null_terminated(x)	(strnlen(x, sizeof(x)) < sizeof(x))
+
+static DEFINE_MUTEX(crypto_cfg_mutex);
+
+struct crypto_dump_info {
+	struct sk_buff *in_skb;
+	struct sk_buff *out_skb;
+	u32 nlmsg_seq;
+	u16 nlmsg_flags;
+};
+
+struct crypto_alg *crypto_alg_match(struct crypto_user_alg *p, int exact)
+{
+	struct crypto_alg *q, *alg = NULL;
+
+	down_read(&crypto_alg_sem);
+
+	list_for_each_entry(q, &crypto_alg_list, cra_list) {
+		int match = 0;
+
+		if (crypto_is_larval(q))
+			continue;
+
+		if ((q->cra_flags ^ p->cru_type) & p->cru_mask)
+			continue;
+
+		if (strlen(p->cru_driver_name))
+			match = !strcmp(q->cra_driver_name,
+					p->cru_driver_name);
+		else if (!exact)
+			match = !strcmp(q->cra_name, p->cru_name);
+
+		if (!match)
+			continue;
+
+		if (unlikely(!crypto_mod_get(q)))
+			continue;
+
+		alg = q;
+		break;
+	}
+
+	up_read(&crypto_alg_sem);
+
+	return alg;
+}
+
+static int crypto_report_cipher(struct sk_buff *skb, struct crypto_alg *alg)
+{
+	struct crypto_report_cipher rcipher;
+
+	memset(&rcipher, 0, sizeof(rcipher));
+
+	strscpy(rcipher.type, "cipher", sizeof(rcipher.type));
+
+	rcipher.blocksize = alg->cra_blocksize;
+	rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
+	rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
+
+	return nla_put(skb, CRYPTOCFGA_REPORT_CIPHER,
+		       sizeof(rcipher), &rcipher);
+}
+
+static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
+{
+	struct crypto_report_comp rcomp;
+
+	memset(&rcomp, 0, sizeof(rcomp));
+
+	strscpy(rcomp.type, "compression", sizeof(rcomp.type));
+
+	return nla_put(skb, CRYPTOCFGA_REPORT_COMPRESS, sizeof(rcomp), &rcomp);
+}
+
+static int crypto_report_one(struct crypto_alg *alg,
+			     struct crypto_user_alg *ualg, struct sk_buff *skb)
+{
+	memset(ualg, 0, sizeof(*ualg));
+
+	strscpy(ualg->cru_name, alg->cra_name, sizeof(ualg->cru_name));
+	strscpy(ualg->cru_driver_name, alg->cra_driver_name,
+		sizeof(ualg->cru_driver_name));
+	strscpy(ualg->cru_module_name, module_name(alg->cra_module),
+		sizeof(ualg->cru_module_name));
+
+	ualg->cru_type = 0;
+	ualg->cru_mask = 0;
+	ualg->cru_flags = alg->cra_flags;
+	ualg->cru_refcnt = refcount_read(&alg->cra_refcnt);
+
+	if (nla_put_u32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority))
+		goto nla_put_failure;
+	if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
+		struct crypto_report_larval rl;
+
+		memset(&rl, 0, sizeof(rl));
+		strscpy(rl.type, "larval", sizeof(rl.type));
+		if (nla_put(skb, CRYPTOCFGA_REPORT_LARVAL, sizeof(rl), &rl))
+			goto nla_put_failure;
+		goto out;
+	}
+
+	if (alg->cra_type && alg->cra_type->report) {
+		if (alg->cra_type->report(skb, alg))
+			goto nla_put_failure;
+
+		goto out;
+	}
+
+	switch (alg->cra_flags & (CRYPTO_ALG_TYPE_MASK | CRYPTO_ALG_LARVAL)) {
+	case CRYPTO_ALG_TYPE_CIPHER:
+		if (crypto_report_cipher(skb, alg))
+			goto nla_put_failure;
+
+		break;
+	case CRYPTO_ALG_TYPE_COMPRESS:
+		if (crypto_report_comp(skb, alg))
+			goto nla_put_failure;
+
+		break;
+	}
+
+out:
+	return 0;
+
+nla_put_failure:
+	return -EMSGSIZE;
+}
+
+static int crypto_report_alg(struct crypto_alg *alg,
+			     struct crypto_dump_info *info)
+{
+	struct sk_buff *in_skb = info->in_skb;
+	struct sk_buff *skb = info->out_skb;
+	struct nlmsghdr *nlh;
+	struct crypto_user_alg *ualg;
+	int err = 0;
+
+	nlh = nlmsg_put(skb, NETLINK_CB(in_skb).portid, info->nlmsg_seq,
+			CRYPTO_MSG_GETALG, sizeof(*ualg), info->nlmsg_flags);
+	if (!nlh) {
+		err = -EMSGSIZE;
+		goto out;
+	}
+
+	ualg = nlmsg_data(nlh);
+
+	err = crypto_report_one(alg, ualg, skb);
+	if (err) {
+		nlmsg_cancel(skb, nlh);
+		goto out;
+	}
+
+	nlmsg_end(skb, nlh);
+
+out:
+	return err;
+}
+
+static int crypto_report(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
+			 struct nlattr **attrs)
+{
+	struct net *net = sock_net(in_skb->sk);
+	struct crypto_user_alg *p = nlmsg_data(in_nlh);
+	struct crypto_alg *alg;
+	struct sk_buff *skb;
+	struct crypto_dump_info info;
+	int err;
+
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
+	alg = crypto_alg_match(p, 0);
+	if (!alg)
+		return -ENOENT;
+
+	err = -ENOMEM;
+	skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_KERNEL);
+	if (!skb)
+		goto drop_alg;
+
+	info.in_skb = in_skb;
+	info.out_skb = skb;
+	info.nlmsg_seq = in_nlh->nlmsg_seq;
+	info.nlmsg_flags = 0;
+
+	err = crypto_report_alg(alg, &info);
+
+drop_alg:
+	crypto_mod_put(alg);
+
+	if (err) {
+		kfree_skb(skb);
+		return err;
+	}
+
+	return nlmsg_unicast(net->crypto_nlsk, skb, NETLINK_CB(in_skb).portid);
+}
+
+static int crypto_dump_report(struct sk_buff *skb, struct netlink_callback *cb)
+{
+	const size_t start_pos = cb->args[0];
+	size_t pos = 0;
+	struct crypto_dump_info info;
+	struct crypto_alg *alg;
+	int res;
+
+	info.in_skb = cb->skb;
+	info.out_skb = skb;
+	info.nlmsg_seq = cb->nlh->nlmsg_seq;
+	info.nlmsg_flags = NLM_F_MULTI;
+
+	down_read(&crypto_alg_sem);
+	list_for_each_entry(alg, &crypto_alg_list, cra_list) {
+		if (pos >= start_pos) {
+			res = crypto_report_alg(alg, &info);
+			if (res == -EMSGSIZE)
+				break;
+			if (res)
+				goto out;
+		}
+		pos++;
+	}
+	cb->args[0] = pos;
+	res = skb->len;
+out:
+	up_read(&crypto_alg_sem);
+	return res;
+}
+
+static int crypto_dump_report_done(struct netlink_callback *cb)
+{
+	return 0;
+}
+
+static int crypto_update_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
+			     struct nlattr **attrs)
+{
+	struct crypto_alg *alg;
+	struct crypto_user_alg *p = nlmsg_data(nlh);
+	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
+	LIST_HEAD(list);
+
+	if (!netlink_capable(skb, CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
+	if (priority && !strlen(p->cru_driver_name))
+		return -EINVAL;
+
+	alg = crypto_alg_match(p, 1);
+	if (!alg)
+		return -ENOENT;
+
+	down_write(&crypto_alg_sem);
+
+	crypto_remove_spawns(alg, &list, NULL);
+
+	if (priority)
+		alg->cra_priority = nla_get_u32(priority);
+
+	up_write(&crypto_alg_sem);
+
+	crypto_mod_put(alg);
+	crypto_remove_final(&list);
+
+	return 0;
+}
+
+static int crypto_del_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
+			  struct nlattr **attrs)
+{
+	struct crypto_alg *alg;
+	struct crypto_user_alg *p = nlmsg_data(nlh);
+	int err;
+
+	if (!netlink_capable(skb, CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
+	alg = crypto_alg_match(p, 1);
+	if (!alg)
+		return -ENOENT;
+
+	/* We can not unregister core algorithms such as aes-generic.
+	 * We would loose the reference in the crypto_alg_list to this algorithm
+	 * if we try to unregister. Unregistering such an algorithm without
+	 * removing the module is not possible, so we restrict to crypto
+	 * instances that are build from templates. */
+	err = -EINVAL;
+	if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
+		goto drop_alg;
+
+	err = -EBUSY;
+	if (refcount_read(&alg->cra_refcnt) > 2)
+		goto drop_alg;
+
+	crypto_unregister_instance((struct crypto_instance *)alg);
+	err = 0;
+
+drop_alg:
+	crypto_mod_put(alg);
+	return err;
+}
+
+static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
+			  struct nlattr **attrs)
+{
+	int exact = 0;
+	const char *name;
+	struct crypto_alg *alg;
+	struct crypto_user_alg *p = nlmsg_data(nlh);
+	struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
+
+	if (!netlink_capable(skb, CAP_NET_ADMIN))
+		return -EPERM;
+
+	if (!null_terminated(p->cru_name) || !null_terminated(p->cru_driver_name))
+		return -EINVAL;
+
+	if (strlen(p->cru_driver_name))
+		exact = 1;
+
+	if (priority && !exact)
+		return -EINVAL;
+
+	alg = crypto_alg_match(p, exact);
+	if (alg) {
+		crypto_mod_put(alg);
+		return -EEXIST;
+	}
+
+	if (strlen(p->cru_driver_name))
+		name = p->cru_driver_name;
+	else
+		name = p->cru_name;
+
+	alg = crypto_alg_mod_lookup(name, p->cru_type, p->cru_mask);
+	if (IS_ERR(alg))
+		return PTR_ERR(alg);
+
+	down_write(&crypto_alg_sem);
+
+	if (priority)
+		alg->cra_priority = nla_get_u32(priority);
+
+	up_write(&crypto_alg_sem);
+
+	crypto_mod_put(alg);
+
+	return 0;
+}
+
+static int crypto_del_rng(struct sk_buff *skb, struct nlmsghdr *nlh,
+			  struct nlattr **attrs)
+{
+	if (!netlink_capable(skb, CAP_NET_ADMIN))
+		return -EPERM;
+	return crypto_del_default_rng();
+}
+
+#define MSGSIZE(type) sizeof(struct type)
+
+static const int crypto_msg_min[CRYPTO_NR_MSGTYPES] = {
+	[CRYPTO_MSG_NEWALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+	[CRYPTO_MSG_DELALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+	[CRYPTO_MSG_UPDATEALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+	[CRYPTO_MSG_GETALG	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+	[CRYPTO_MSG_DELRNG	- CRYPTO_MSG_BASE] = 0,
+	[CRYPTO_MSG_GETSTAT	- CRYPTO_MSG_BASE] = MSGSIZE(crypto_user_alg),
+};
+
+static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
+	[CRYPTOCFGA_PRIORITY_VAL]   = { .type = NLA_U32},
+};
+
+#undef MSGSIZE
+
+static const struct crypto_link {
+	int (*doit)(struct sk_buff *, struct nlmsghdr *, struct nlattr **);
+	int (*dump)(struct sk_buff *, struct netlink_callback *);
+	int (*done)(struct netlink_callback *);
+} crypto_dispatch[CRYPTO_NR_MSGTYPES] = {
+	[CRYPTO_MSG_NEWALG	- CRYPTO_MSG_BASE] = { .doit = crypto_add_alg},
+	[CRYPTO_MSG_DELALG	- CRYPTO_MSG_BASE] = { .doit = crypto_del_alg},
+	[CRYPTO_MSG_UPDATEALG	- CRYPTO_MSG_BASE] = { .doit = crypto_update_alg},
+	[CRYPTO_MSG_GETALG	- CRYPTO_MSG_BASE] = { .doit = crypto_report,
+						       .dump = crypto_dump_report,
+						       .done = crypto_dump_report_done},
+	[CRYPTO_MSG_DELRNG	- CRYPTO_MSG_BASE] = { .doit = crypto_del_rng },
+	[CRYPTO_MSG_GETSTAT	- CRYPTO_MSG_BASE] = { .doit = crypto_reportstat},
+};
+
+static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh,
+			       struct netlink_ext_ack *extack)
+{
+	struct net *net = sock_net(skb->sk);
+	struct nlattr *attrs[CRYPTOCFGA_MAX+1];
+	const struct crypto_link *link;
+	int type, err;
+
+	type = nlh->nlmsg_type;
+	if (type > CRYPTO_MSG_MAX)
+		return -EINVAL;
+
+	type -= CRYPTO_MSG_BASE;
+	link = &crypto_dispatch[type];
+
+	if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
+	    (nlh->nlmsg_flags & NLM_F_DUMP))) {
+		struct crypto_alg *alg;
+		unsigned long dump_alloc = 0;
+
+		if (link->dump == NULL)
+			return -EINVAL;
+
+		down_read(&crypto_alg_sem);
+		list_for_each_entry(alg, &crypto_alg_list, cra_list)
+			dump_alloc += CRYPTO_REPORT_MAXSIZE;
+		up_read(&crypto_alg_sem);
+
+		{
+			struct netlink_dump_control c = {
+				.dump = link->dump,
+				.done = link->done,
+				.min_dump_alloc = min(dump_alloc, 65535UL),
+			};
+			err = netlink_dump_start(net->crypto_nlsk, skb, nlh, &c);
+		}
+
+		return err;
+	}
+
+	err = nlmsg_parse_deprecated(nlh, crypto_msg_min[type], attrs,
+				     CRYPTOCFGA_MAX, crypto_policy, extack);
+	if (err < 0)
+		return err;
+
+	if (link->doit == NULL)
+		return -EINVAL;
+
+	return link->doit(skb, nlh, attrs);
+}
+
+static void crypto_netlink_rcv(struct sk_buff *skb)
+{
+	mutex_lock(&crypto_cfg_mutex);
+	netlink_rcv_skb(skb, &crypto_user_rcv_msg);
+	mutex_unlock(&crypto_cfg_mutex);
+}
+
+static int __net_init crypto_netlink_init(struct net *net)
+{
+	struct netlink_kernel_cfg cfg = {
+		.input	= crypto_netlink_rcv,
+	};
+
+	net->crypto_nlsk = netlink_kernel_create(net, NETLINK_CRYPTO, &cfg);
+	return net->crypto_nlsk == NULL ? -ENOMEM : 0;
+}
+
+static void __net_exit crypto_netlink_exit(struct net *net)
+{
+	netlink_kernel_release(net->crypto_nlsk);
+	net->crypto_nlsk = NULL;
+}
+
+static struct pernet_operations crypto_netlink_net_ops = {
+	.init = crypto_netlink_init,
+	.exit = crypto_netlink_exit,
+};
+
+static int __init crypto_user_init(void)
+{
+	return register_pernet_subsys(&crypto_netlink_net_ops);
+}
+
+static void __exit crypto_user_exit(void)
+{
+	unregister_pernet_subsys(&crypto_netlink_net_ops);
+}
+
+module_init(crypto_user_init);
+module_exit(crypto_user_exit);
+MODULE_LICENSE("GPL");
+MODULE_AUTHOR("Steffen Klassert <steffen.klassert@secunet.com>");
+MODULE_DESCRIPTION("Crypto userspace configuration API");
+MODULE_ALIAS("net-pf-16-proto-21");