44 lines
1.4 KiB
Plaintext
44 lines
1.4 KiB
Plaintext
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Ruby Netlink
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============
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This library provides an API for using a Linux Netlink socket, for doing
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things like manipulating IP interfaces, routes and firewall rules
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programmatically.
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Useful reference material
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=========================
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* http://www.linuxjournal.com/article/7356
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* http://people.redhat.com/nhorman/papers/netlink.pdf
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* apt-get source iproute
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Note there are some errors in the nhorman paper. On page 8/9, it says
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nlmsg_pid ... Also note that it is
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imperative that any program receiving netlink socket messages from
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the kernel verify that this field is set to zero, or it is possible to expose
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the software to unexpected influences from other non-privlidged user
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space programs.
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However, what really needs to be checked is the pid in the sockaddr_nl
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structure returned by recvmsg msghdr, as shown by this code in
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lib/libnetlink.c:
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struct msghdr msg = {
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.msg_name = &nladdr,
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.msg_namelen = sizeof(nladdr),
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.msg_iov = &iov,
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.msg_iovlen = 1,
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};
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...
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status = recvmsg(rth->fd, &msg, 0);
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...
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if (nladdr.nl_pid != 0 ||
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h->nlmsg_pid != rth->local.nl_pid ||
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h->nlmsg_seq != rth->dump) {
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Copyright
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=========
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Copyright (C) 2011 Bytemark Computer Consulting Ltd
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