From 91b05a7e7d8033a90a64f5fc0e3808db423e420a Mon Sep 17 00:00:00 2001 From: Ondrej Mosnacek Date: Tue, 9 Jul 2019 13:11:24 +0200 Subject: [PATCH] crypto: user - make NETLINK_CRYPTO work inside netns Currently, NETLINK_CRYPTO works only in the init network namespace. It doesn't make much sense to cut it out of the other network namespaces, so do the minor plumbing work necessary to make it work in any network namespace. Code inspired by net/core/sock_diag.c. Tested using kcapi-dgst from libkcapi [1]: Before: # unshare -n kcapi-dgst -c sha256 Signed-off-by: Herbert Xu --- crypto/crypto_user_base.c | 37 ++++++++++++++++++++++++------------ crypto/crypto_user_stat.c | 4 +++- include/crypto/internal/cryptouser.h | 2 -- include/net/net_namespace.h | 3 +++ 4 files changed, 31 insertions(+), 15 deletions(-) diff --git a/crypto/crypto_user_base.c b/crypto/crypto_user_base.c index c65e390..910e0b4 100644 --- a/crypto/crypto_user_base.c +++ b/crypto/crypto_user_base.c @@ -10,9 +10,10 @@ #include #include #include -#include #include +#include #include +#include #include #include #include @@ -25,9 +26,6 @@ static DEFINE_MUTEX(crypto_cfg_mutex); -/* The crypto netlink socket */ -struct sock *crypto_nlsk; - struct crypto_dump_info { struct sk_buff *in_skb; struct sk_buff *out_skb; @@ -186,6 +184,7 @@ out: 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; @@ -217,7 +216,7 @@ drop_alg: if (err) return err; - return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid); + 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) @@ -420,6 +419,7 @@ static const struct crypto_link { 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; @@ -450,7 +450,7 @@ static int crypto_user_rcv_msg(struct sk_buff *skb, struct nlmsghdr *nlh, .done = link->done, .min_dump_alloc = min(dump_alloc, 65535UL), }; - err = netlink_dump_start(crypto_nlsk, skb, nlh, &c); + err = netlink_dump_start(net->crypto_nlsk, skb, nlh, &c); } return err; @@ -474,22 +474,35 @@ static void crypto_netlink_rcv(struct sk_buff *skb) mutex_unlock(&crypto_cfg_mutex); } -static int __init crypto_user_init(void) +static int __net_init crypto_netlink_init(struct net *net) { struct netlink_kernel_cfg cfg = { .input = crypto_netlink_rcv, }; - crypto_nlsk = netlink_kernel_create(&init_net, NETLINK_CRYPTO, &cfg); - if (!crypto_nlsk) - return -ENOMEM; + net->crypto_nlsk = netlink_kernel_create(net, NETLINK_CRYPTO, &cfg); + return net->crypto_nlsk == NULL ? -ENOMEM : 0; +} - return 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) { - netlink_kernel_release(crypto_nlsk); + unregister_pernet_subsys(&crypto_netlink_net_ops); } module_init(crypto_user_init); diff --git a/crypto/crypto_user_stat.c b/crypto/crypto_user_stat.c index a03f326..8bad884 100644 --- a/crypto/crypto_user_stat.c +++ b/crypto/crypto_user_stat.c @@ -10,6 +10,7 @@ #include #include #include +#include #include #include #include @@ -298,6 +299,7 @@ out: int crypto_reportstat(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; @@ -329,7 +331,7 @@ drop_alg: if (err) return err; - return nlmsg_unicast(crypto_nlsk, skb, NETLINK_CB(in_skb).portid); + return nlmsg_unicast(net->crypto_nlsk, skb, NETLINK_CB(in_skb).portid); } MODULE_LICENSE("GPL"); diff --git a/include/crypto/internal/cryptouser.h b/include/crypto/internal/cryptouser.h index 8c602b1..40623f4 100644 --- a/include/crypto/internal/cryptouser.h +++ b/include/crypto/internal/cryptouser.h @@ -1,8 +1,6 @@ /* SPDX-License-Identifier: GPL-2.0 */ #include -extern struct sock *crypto_nlsk; - struct crypto_alg *crypto_alg_match(struct crypto_user_alg *p, int exact); #ifdef CONFIG_CRYPTO_STATS diff --git a/include/net/net_namespace.h b/include/net/net_namespace.h index 4a9da95..85bc1de 100644 --- a/include/net/net_namespace.h +++ b/include/net/net_namespace.h @@ -171,6 +171,9 @@ struct net { #ifdef CONFIG_XDP_SOCKETS struct netns_xdp xdp; #endif +#if IS_ENABLED(CONFIG_CRYPTO_USER) + struct sock *crypto_nlsk; +#endif struct sock *diag_nlsk; atomic_t fnhe_genid; } __randomize_layout; -- 2.7.4