From 738f378d77b04f685f2cd01aa4240d1bce5c9668 Mon Sep 17 00:00:00 2001 From: "Eric W. Biederman" Date: Wed, 23 Apr 2014 14:28:03 -0700 Subject: net: Add variants of capable for use on netlink messages [ Upstream commit aa4cf9452f469f16cea8c96283b641b4576d4a7b ] 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" Signed-off-by: David S. Miller Signed-off-by: Greg Kroah-Hartman --- 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 6358da5eeee..438b312aa05 100644 --- a/include/linux/netlink.h +++ b/include/linux/netlink.h @@ -144,4 +144,11 @@ static inline int netlink_dump_start(struct sock *ssk, struct sk_buff *skb, return __netlink_dump_start(ssk, skb, nlh, control); } +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 3f1d67e7cf5..e846e3e361f 100644 --- a/net/netlink/af_netlink.c +++ b/net/netlink/af_netlink.c @@ -1219,6 +1219,71 @@ 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) || -- cgit v1.2.3-18-g5258