| /* |
| * 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_instance(alg); |
| } |
| |
| 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 (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"); |