From mboxrd@z Thu Jan 1 00:00:00 1970 From: ebiederm@xmission.com (Eric W. Biederman) Subject: [PATCH 5/6] net: Add variants of capable for use on netlink messages Date: Tue, 22 Apr 2014 14:16:41 -0700 Message-ID: <87zjjdm5dy.fsf_-_@x220.int.ebiederm.org> References: <6daf425e2023266d52d181e4d2ee18747d4f1fa8.1397840611.git.luto@amacapital.net> <87tx9nuxf6.fsf@x220.int.ebiederm.org> <87r44qtabz.fsf@x220.int.ebiederm.org> <87r44qrt8v.fsf_-_@x220.int.ebiederm.org> <87r44pnk3c.fsf@x220.int.ebiederm.org> Mime-Version: 1.0 Content-Type: text/plain Cc: Vivek Goyal , Simo Sorce , "security\@kernel.org" , Andy Lutomirski , , "Serge E. Hallyn" To: "David S. Miller" Return-path: Received: from out01.mta.xmission.com ([166.70.13.231]:49835 "EHLO out01.mta.xmission.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S932306AbaDVVRT (ORCPT ); Tue, 22 Apr 2014 17:17:19 -0400 In-Reply-To: <87r44pnk3c.fsf@x220.int.ebiederm.org> (Eric W. Biederman's message of "Tue, 22 Apr 2014 14:13:43 -0700") Sender: netdev-owner@vger.kernel.org List-ID: netlink_net_capable - The common case use, for operations that are safe on a network namespace netlink_capable - For operations that are only known to be safe for the global root netlink_ns_capable - The general case of capable used to handle special cases __netlink_ns_capable - Same as netlink_ns_capable except taking a netlink_skb_parms instead of the skbuff of a netlink message. Signed-off-by: "Eric W. Biederman" --- include/linux/netlink.h | 7 ++++++ net/netlink/af_netlink.c | 65 ++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 72 insertions(+) diff --git a/include/linux/netlink.h b/include/linux/netlink.h index aad8eeaf416d..f64b01787ddc 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -169,4 +169,11 @@ struct netlink_tap { extern int netlink_add_tap(struct netlink_tap *nt); extern int netlink_remove_tap(struct netlink_tap *nt); +bool __netlink_ns_capable(const struct netlink_skb_parms *nsp, + struct user_namespace *ns, int cap); +bool netlink_ns_capable(const struct sk_buff *skb, + struct user_namespace *ns, int cap); +bool netlink_capable(const struct sk_buff *skb, int cap); +bool netlink_net_capable(const struct sk_buff *skb, int cap); + #endif /* __LINUX_NETLINK_H */ diff --git a/net/netlink/af_netlink.c b/net/netlink/af_netlink.c index 7f931fe4d187..81dca96d2be6 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1360,6 +1360,71 @@ retry: return err; } +/** + * __netlink_ns_capable - General netlink message capability test + * @nsp: NETLINK_CB of the socket buffer holding a netlink command from userspace. + * @user_ns: The user namespace of the capability to use + * @cap: The capability to use + * + * Test to see if the opener of the socket we received the message + * from had when the netlink socket was created and the sender of the + * message has has the capability @cap in the user namespace @user_ns. + */ +bool __netlink_ns_capable(const struct netlink_skb_parms *nsp, + struct user_namespace *user_ns, int cap) +{ + return sk_ns_capable(nsp->sk, user_ns, cap); +} +EXPORT_SYMBOL(__netlink_ns_capable); + +/** + * netlink_ns_capable - General netlink message capability test + * @skb: socket buffer holding a netlink command from userspace + * @user_ns: The user namespace of the capability to use + * @cap: The capability to use + * + * Test to see if the opener of the socket we received the message + * from had when the netlink socket was created and the sender of the + * message has has the capability @cap in the user namespace @user_ns. + */ +bool netlink_ns_capable(const struct sk_buff *skb, + struct user_namespace *user_ns, int cap) +{ + return __netlink_ns_capable(&NETLINK_CB(skb), user_ns, cap); +} +EXPORT_SYMBOL(netlink_ns_capable); + +/** + * netlink_capable - Netlink global message capability test + * @skb: socket buffer holding a netlink command from userspace + * @cap: The capability to use + * + * Test to see if the opener of the socket we received the message + * from had when the netlink socket was created and the sender of the + * message has has the capability @cap in all user namespaces. + */ +bool netlink_capable(const struct sk_buff *skb, int cap) +{ + return netlink_ns_capable(skb, &init_user_ns, cap); +} +EXPORT_SYMBOL(netlink_capable); + +/** + * netlink_net_capable - Netlink network namespace message capability test + * @skb: socket buffer holding a netlink command from userspace + * @cap: The capability to use + * + * Test to see if the opener of the socket we received the message + * from had when the netlink socket was created and the sender of the + * message has has the capability @cap over the network namespace of + * the socket we received the message from. + */ +bool netlink_net_capable(const struct sk_buff *skb, int cap) +{ + return netlink_ns_capable(skb, sock_net(skb->sk)->user_ns, cap); +} +EXPORT_SYMBOL(netlink_net_capable); + static inline int netlink_allowed(const struct socket *sock, unsigned int flag) { return (nl_table[sock->sk->sk_protocol].flags & flag) || -- 1.9.1