From 8917a777be3ba566377be05117f71b93a5fd909d Mon Sep 17 00:00:00 2001 From: Ivan Delalande Date: Thu, 15 Jun 2017 18:07:07 -0700 Subject: tcp: md5: add TCP_MD5SIG_EXT socket option to set a key address prefix Replace first padding in the tcp_md5sig structure with a new flag field and address prefix length so it can be specified when configuring a new key for TCP MD5 signature. The tcpm_flags field will only be used if the socket option is TCP_MD5SIG_EXT to avoid breaking existing programs, and tcpm_prefixlen only when the TCP_MD5SIG_FLAG_PREFIX flag is set. Signed-off-by: Bob Gilligan Signed-off-by: Eric Mowat Signed-off-by: Ivan Delalande Signed-off-by: David S. Miller --- net/ipv4/tcp_ipv4.c | 16 ++++++++++++---- 1 file changed, 12 insertions(+), 4 deletions(-) (limited to 'net/ipv4/tcp_ipv4.c') diff --git a/net/ipv4/tcp_ipv4.c b/net/ipv4/tcp_ipv4.c index a3c67866b780..bf407f3e20dd 100644 --- a/net/ipv4/tcp_ipv4.c +++ b/net/ipv4/tcp_ipv4.c @@ -1066,11 +1066,12 @@ static void tcp_clear_md5_list(struct sock *sk) } } -static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval, - int optlen) +static int tcp_v4_parse_md5_keys(struct sock *sk, int optname, + char __user *optval, int optlen) { struct tcp_md5sig cmd; struct sockaddr_in *sin = (struct sockaddr_in *)&cmd.tcpm_addr; + u8 prefixlen = 32; if (optlen < sizeof(cmd)) return -EINVAL; @@ -1081,15 +1082,22 @@ static int tcp_v4_parse_md5_keys(struct sock *sk, char __user *optval, if (sin->sin_family != AF_INET) return -EINVAL; + if (optname == TCP_MD5SIG_EXT && + cmd.tcpm_flags & TCP_MD5SIG_FLAG_PREFIX) { + prefixlen = cmd.tcpm_prefixlen; + if (prefixlen > 32) + return -EINVAL; + } + if (!cmd.tcpm_keylen) return tcp_md5_do_del(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, - AF_INET, 32); + AF_INET, prefixlen); if (cmd.tcpm_keylen > TCP_MD5SIG_MAXKEYLEN) return -EINVAL; return tcp_md5_do_add(sk, (union tcp_md5_addr *)&sin->sin_addr.s_addr, - AF_INET, 32, cmd.tcpm_key, cmd.tcpm_keylen, + AF_INET, prefixlen, cmd.tcpm_key, cmd.tcpm_keylen, GFP_KERNEL); } -- cgit v1.2.3-59-g8ed1b