Merge tag 'v6.10-p1' of git://git.kernel.org/pub/scm/linux/kernel/git/herbert/crypto-2.6
[linux-block.git] / crypto / crypto_user.c
diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
new file mode 100644 (file)
index 0000000..6c57183
--- /dev/null
@@ -0,0 +1,522 @@
+// 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 "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;
+};
+
+static 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();
+}
+
+static int crypto_reportstat(struct sk_buff *in_skb, struct nlmsghdr *in_nlh,
+                            struct nlattr **attrs)
+{
+       /* No longer supported */
+       return -ENOTSUPP;
+}
+
+#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");