diff options
Diffstat (limited to 'zebra/rt_netlink.c')
| -rw-r--r-- | zebra/rt_netlink.c | 32 |
1 files changed, 18 insertions, 14 deletions
diff --git a/zebra/rt_netlink.c b/zebra/rt_netlink.c index 273c3121..f84d6596 100644 --- a/zebra/rt_netlink.c +++ b/zebra/rt_netlink.c @@ -1939,22 +1939,26 @@ kernel_read (struct thread *thread) return 0; } -/* Filter out messages from self that occur on listener socket */ -static void netlink_install_filter (int sock) +/* Filter out messages from self that occur on listener socket, + caused by our actions on the command socket + */ +static void netlink_install_filter (int sock, __u32 pid) { - /* BPF code to exclude all RTM_NEWROUTE messages from ZEBRA */ struct sock_filter filter[] = { + /* 0: ldh [4] */ BPF_STMT(BPF_LD|BPF_ABS|BPF_H, offsetof(struct nlmsghdr, nlmsg_type)), - /* 0: ldh [4] */ - BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, htons(RTM_NEWROUTE), 0, 3), - /* 1: jeq 0x18 jt 2 jf 5 */ - BPF_STMT(BPF_LD|BPF_ABS|BPF_B, - sizeof(struct nlmsghdr) + offsetof(struct rtmsg, rtm_protocol)), - /* 2: ldb [23] */ - BPF_JUMP(BPF_JMP+ BPF_B, RTPROT_ZEBRA, 0, 1), - /* 3: jeq 0xb jt 4 jf 5 */ - BPF_STMT(BPF_RET|BPF_K, 0), /* 4: ret 0 */ - BPF_STMT(BPF_RET|BPF_K, 0xffff), /* 5: ret 0xffff */ + /* 1: jeq 0x18 jt 3 jf 6 */ + BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, htons(RTM_NEWROUTE), 1, 0), + /* 2: jeq 0x19 jt 3 jf 6 */ + BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, htons(RTM_DELROUTE), 0, 3), + /* 3: ldw [12] */ + BPF_STMT(BPF_LD|BPF_ABS|BPF_W, offsetof(struct nlmsghdr, nlmsg_pid)), + /* 4: jeq XX jt 5 jf 6 */ + BPF_JUMP(BPF_JMP|BPF_JEQ|BPF_K, htonl(pid), 0, 1), + /* 5: ret 0 (skip) */ + BPF_STMT(BPF_RET|BPF_K, 0), + /* 6: ret 0xffff (keep) */ + BPF_STMT(BPF_RET|BPF_K, 0xffff), }; struct sock_fprog prog = { @@ -1983,7 +1987,7 @@ kernel_init (void) /* Register kernel socket. */ if (netlink.sock > 0) { - netlink_install_filter (netlink.sock); + netlink_install_filter (netlink.sock, netlink_cmd.snl.nl_pid); thread_add_read (zebrad.master, kernel_read, NULL, netlink.sock); } } |