1 files changed, 435 insertions, 0 deletions

diff --git a/crypto/crypto_user.c b/crypto/crypto_user.c
new file mode 100644
index 00000000000..0605a2bbba7
--- /dev/null
+++ b/crypto/crypto_user.c
@@ -0,0 +1,435 @@
+/*
+ * Crypto user configuration API.
+ *
+ * Copyright (C) 2011 secunet Security Networks AG
+ * Copyright (C) 2011 Steffen Klassert <steffen.klassert@secunet.com>
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms and conditions of the GNU General Public License,
+ * version 2, as published by the Free Software Foundation.
+ *
+ * This program is distributed in the hope it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE.  See the GNU General Public License for
+ * more details.
+ *
+ * You should have received a copy of the GNU General Public License along with
+ * this program; if not, write to the Free Software Foundation, Inc.,
+ * 51 Franklin St - Fifth Floor, Boston, MA 02110-1301 USA.
+ */
+
+#include <linux/module.h>
+#include <linux/crypto.h>
+#include <linux/cryptouser.h>
+#include <net/netlink.h>
+#include <linux/security.h>
+#include <net/net_namespace.h>
+#include "internal.h"
+
+DEFINE_MUTEX(crypto_cfg_mutex);
+
+/* The crypto netlink socket */
+static struct sock *crypto_nlsk;
+
+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 ((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) {
+                        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;
+
+        snprintf(rcipher.type, CRYPTO_MAX_ALG_NAME, "%s", "cipher");
+
+        rcipher.blocksize = alg->cra_blocksize;
+        rcipher.min_keysize = alg->cra_cipher.cia_min_keysize;
+        rcipher.max_keysize = alg->cra_cipher.cia_max_keysize;
+
+        NLA_PUT(skb, CRYPTOCFGA_REPORT_CIPHER,
+                sizeof(struct crypto_report_cipher), &rcipher);
+
+        return 0;
+
+nla_put_failure:
+        return -EMSGSIZE;
+}
+
+static int crypto_report_comp(struct sk_buff *skb, struct crypto_alg *alg)
+{
+        struct crypto_report_comp rcomp;
+
+        snprintf(rcomp.type, CRYPTO_MAX_ALG_NAME, "%s", "compression");
+
+        NLA_PUT(skb, CRYPTOCFGA_REPORT_COMPRESS,
+                sizeof(struct crypto_report_comp), &rcomp);
+
+        return 0;
+
+nla_put_failure:
+        return -EMSGSIZE;
+}
+
+static int crypto_report_one(struct crypto_alg *alg,
+                             struct crypto_user_alg *ualg, struct sk_buff *skb)
+{
+        memcpy(&ualg->cru_name, &alg->cra_name, sizeof(ualg->cru_name));
+        memcpy(&ualg->cru_driver_name, &alg->cra_driver_name,
+               sizeof(ualg->cru_driver_name));
+        memcpy(&ualg->cru_module_name, module_name(alg->cra_module),
+               CRYPTO_MAX_ALG_NAME);
+
+        ualg->cru_flags = alg->cra_flags;
+        ualg->cru_refcnt = atomic_read(&alg->cra_refcnt);
+
+        NLA_PUT_U32(skb, CRYPTOCFGA_PRIORITY_VAL, alg->cra_priority);
+
+        if (alg->cra_flags & CRYPTO_ALG_LARVAL) {
+                struct crypto_report_larval rl;
+
+                snprintf(rl.type, CRYPTO_MAX_ALG_NAME, "%s", "larval");
+
+                NLA_PUT(skb, CRYPTOCFGA_REPORT_LARVAL,
+                        sizeof(struct crypto_report_larval), &rl);
+
+                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).pid, 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 crypto_user_alg *p = nlmsg_data(in_nlh);
+        struct crypto_alg *alg;
+        struct sk_buff *skb;
+        struct crypto_dump_info info;
+        int err;
+
+        if (!p->cru_driver_name)
+                return -EINVAL;
+
+        alg = crypto_alg_match(p, 1);
+        if (!alg)
+                return -ENOENT;
+
+        skb = nlmsg_new(NLMSG_DEFAULT_SIZE, GFP_ATOMIC);
+        if (!skb)
+                return -ENOMEM;
+
+        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);
+        if (err)
+                return err;
+
+        return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).pid);
+}
+
+static int crypto_dump_report(struct sk_buff *skb, struct netlink_callback *cb)
+{
+        struct crypto_alg *alg;
+        struct crypto_dump_info info;
+        int err;
+
+        if (cb->args[0])
+                goto out;
+
+        cb->args[0] = 1;
+
+        info.in_skb = cb->skb;
+        info.out_skb = skb;
+        info.nlmsg_seq = cb->nlh->nlmsg_seq;
+        info.nlmsg_flags = NLM_F_MULTI;
+
+        list_for_each_entry(alg, &crypto_alg_list, cra_list) {
+                err = crypto_report_alg(alg, &info);
+                if (err)
+                        goto out_err;
+        }
+
+out:
+        return skb->len;
+out_err:
+        return err;
+}
+
+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 (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_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);
+
+        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. */
+        if (!(alg->cra_flags & CRYPTO_ALG_INSTANCE))
+                return -EINVAL;
+
+        if (atomic_read(&alg->cra_refcnt) != 1)
+                return -EBUSY;
+
+        return crypto_unregister_alg(alg);
+}
+
+static int crypto_add_alg(struct sk_buff *skb, struct nlmsghdr *nlh,
+                          struct nlattr **attrs)
+{
+        int exact;
+        const char *name;
+        struct crypto_alg *alg;
+        struct crypto_user_alg *p = nlmsg_data(nlh);
+        struct nlattr *priority = attrs[CRYPTOCFGA_PRIORITY_VAL];
+
+        if (strlen(p->cru_driver_name))
+                exact = 1;
+
+        if (priority && !exact)
+                return -EINVAL;
+
+        alg = crypto_alg_match(p, exact);
+        if (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;
+}
+
+#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),
+};
+
+static const struct nla_policy crypto_policy[CRYPTOCFGA_MAX+1] = {
+        [CRYPTOCFGA_PRIORITY_VAL]   = { .type = NLA_U32},
+};
+
+#undef MSGSIZE
+
+static 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},
+};
+
+static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh)
+{
+        struct nlattr *attrs[CRYPTOCFGA_MAX+1];
+        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 (security_netlink_recv(skb, CAP_NET_ADMIN))
+                return -EPERM;
+
+        if ((type == (CRYPTO_MSG_GETALG - CRYPTO_MSG_BASE) &&
+            (nlh->nlmsg_flags & NLM_F_DUMP))) {
+                if (link->dump == NULL)
+                        return -EINVAL;
+
+                return netlink_dump_start(crypto_nlsk, skb, nlh,
+                                          link->dump, link->done, 0);
+        }
+
+        err = nlmsg_parse(nlh, crypto_msg_min[type], attrs, CRYPTOCFGA_MAX,
+                          crypto_policy);
+        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 __init crypto_user_init(void)
+{
+        crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO,
+                                            0, crypto_netlink_rcv,
+                                            NULL, THIS_MODULE);
+        if (!crypto_nlsk)
+                return -ENOMEM;
+
+        return 0;
+}
+
+static void __exit crypto_user_exit(void)
+{
+        netlink_kernel_release(crypto_nlsk);
+}
+
+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");