Commit a52e95ab authored by Lorenzo Colitti's avatar Lorenzo Colitti Committed by David S. Miller
Browse files

net: diag: allow socket bytecode filters to match socket marks

This allows a privileged process to filter by socket mark when
dumping sockets via INET_DIAG_BY_FAMILY. This is useful on
systems that use mark-based routing such as Android.

The ability to filter socket marks requires CAP_NET_ADMIN, which
is consistent with other privileged operations allowed by the
SOCK_DIAG interface such as the ability to destroy sockets and
the ability to inspect BPF filters attached to packet sockets.

Tested: https://android-review.googlesource.com/261350

Signed-off-by: default avatarLorenzo Colitti <lorenzo@google.com>
Acked-by: default avatarDavid Ahern <dsa@cumulusnetworks.com>
Signed-off-by: default avatarDavid S. Miller <davem@davemloft.net>
parent 627cc4ad
......@@ -73,6 +73,7 @@ enum {
INET_DIAG_BC_S_COND,
INET_DIAG_BC_D_COND,
INET_DIAG_BC_DEV_COND, /* u32 ifindex */
INET_DIAG_BC_MARK_COND,
};
struct inet_diag_hostcond {
......@@ -82,6 +83,11 @@ struct inet_diag_hostcond {
__be32 addr[0];
};
struct inet_diag_markcond {
__u32 mark;
__u32 mask;
};
/* Base info structure. It contains socket identity (addrs/ports/cookie)
* and, alas, the information shown by netstat. */
struct inet_diag_msg {
......
......@@ -45,6 +45,7 @@ struct inet_diag_entry {
u16 family;
u16 userlocks;
u32 ifindex;
u32 mark;
};
static DEFINE_MUTEX(inet_diag_table_mutex);
......@@ -580,6 +581,14 @@ static int inet_diag_bc_run(const struct nlattr *_bc,
yes = 0;
break;
}
case INET_DIAG_BC_MARK_COND: {
struct inet_diag_markcond *cond;
cond = (struct inet_diag_markcond *)(op + 1);
if ((entry->mark & cond->mask) != cond->mark)
yes = 0;
break;
}
}
if (yes) {
......@@ -624,6 +633,12 @@ int inet_diag_bc_sk(const struct nlattr *bc, struct sock *sk)
entry.dport = ntohs(inet->inet_dport);
entry.ifindex = sk->sk_bound_dev_if;
entry.userlocks = sk_fullsock(sk) ? sk->sk_userlocks : 0;
if (sk_fullsock(sk))
entry.mark = sk->sk_mark;
else if (sk->sk_state == TCP_NEW_SYN_RECV)
entry.mark = inet_rsk(inet_reqsk(sk))->ir_mark;
else
entry.mark = 0;
return inet_diag_bc_run(bc, &entry);
}
......@@ -706,8 +721,17 @@ static bool valid_port_comparison(const struct inet_diag_bc_op *op,
return true;
}
static int inet_diag_bc_audit(const struct nlattr *attr)
static bool valid_markcond(const struct inet_diag_bc_op *op, int len,
int *min_len)
{
*min_len += sizeof(struct inet_diag_markcond);
return len >= *min_len;
}
static int inet_diag_bc_audit(const struct nlattr *attr,
const struct sk_buff *skb)
{
bool net_admin = netlink_net_capable(skb, CAP_NET_ADMIN);
const void *bytecode, *bc;
int bytecode_len, len;
......@@ -738,6 +762,12 @@ static int inet_diag_bc_audit(const struct nlattr *attr)
if (!valid_port_comparison(bc, len, &min_len))
return -EINVAL;
break;
case INET_DIAG_BC_MARK_COND:
if (!net_admin)
return -EPERM;
if (!valid_markcond(bc, len, &min_len))
return -EINVAL;
break;
case INET_DIAG_BC_AUTO:
case INET_DIAG_BC_JMP:
case INET_DIAG_BC_NOP:
......@@ -1030,7 +1060,7 @@ static int inet_diag_rcv_msg_compat(struct sk_buff *skb, struct nlmsghdr *nlh)
attr = nlmsg_find_attr(nlh, hdrlen,
INET_DIAG_REQ_BYTECODE);
err = inet_diag_bc_audit(attr);
err = inet_diag_bc_audit(attr, skb);
if (err)
return err;
}
......@@ -1061,7 +1091,7 @@ static int inet_diag_handler_cmd(struct sk_buff *skb, struct nlmsghdr *h)
attr = nlmsg_find_attr(h, hdrlen,
INET_DIAG_REQ_BYTECODE);
err = inet_diag_bc_audit(attr);
err = inet_diag_bc_audit(attr, skb);
if (err)
return err;
}
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment