[PATCH v2 17/18] gtp: add support to select a GTP socket during PDP context creation

[Andreas Schultz]

Signed-off-by: Andreas Schultz <aschu...@tpip.net>
---
 drivers/net/gtp.c | 68 ++++++++++++++++++++++++++++++++++++++++++++++++++++---
 1 file changed, 65 insertions(+), 3 deletions(-)

diff --git a/drivers/net/gtp.c b/drivers/net/gtp.c
index c6c1f0d..4637ce7 100644
--- a/drivers/net/gtp.c
+++ b/drivers/net/gtp.c
@@ -1023,6 +1023,7 @@ static int gtp_genl_new_pdp(struct sk_buff *skb, struct 
genl_info *info)
        struct net_device *dev;
        struct net *net;
        struct socket *sock;
+       int err;
 
        if (!info->attrs[GTPA_VERSION] ||
            !info->attrs[GTPA_LINK] ||
@@ -1060,11 +1061,19 @@ static int gtp_genl_new_pdp(struct sk_buff *skb, struct 
genl_info *info)
        }
        put_net(net);
 
-       sock = gtp_genl_new_pdp_select_socket(version, dev);
-       if (!sock)
+       if (info->attrs[GTPA_FD])
+               sock = sockfd_lookup(nla_get_u32(info->attrs[GTPA_FD]), &err);
+       else
+               sock = gtp_genl_new_pdp_select_socket(version, dev);
+       if (!sock || !sock->sk)
                return -ENODEV;
 
-       return ipv4_pdp_add(dev, sock->sk, info);
+       err = ipv4_pdp_add(dev, sock->sk, info);
+
+       if (info->attrs[GTPA_FD])
+               sockfd_put(sock);
+
+       return err;
 }
 
 static struct pdp_ctx *gtp_genl_find_pdp_by_link(struct sk_buff *skb,
@@ -1096,11 +1105,64 @@ static struct pdp_ctx *gtp_genl_find_pdp_by_link(struct 
sk_buff *skb,
        return ipv4_pdp_find(gtp, ms_addr);
 }
 
+static struct pdp_ctx *gtp_genl_find_pdp_by_socket(struct sk_buff *skb,
+                                                  struct genl_info *info)
+{
+       struct socket *sock;
+       struct gtp_sock *gsk;
+       struct pdp_ctx *pctx;
+       int fd, err = 0;
+
+       if (!info->attrs[GTPA_FD])
+               return ERR_PTR(-EINVAL);
+
+       fd = nla_get_u32(info->attrs[GTPA_FD]);
+       sock = sockfd_lookup(fd, &err);
+       if (!sock) {
+               pr_debug("gtp socket fd=%d not found\n", fd);
+               return ERR_PTR(-EBADF);
+       }
+
+       gsk = rcu_dereference_sk_user_data(sock->sk);
+       if (!gsk) {
+               pctx = ERR_PTR(-EINVAL);
+               goto out_sock;
+       }
+
+       switch (nla_get_u32(info->attrs[GTPA_VERSION])) {
+       case GTP_V0:
+               if (!info->attrs[GTPA_TID]) {
+                       pctx = ERR_PTR(-EINVAL);
+                       break;
+               }
+               pctx = gtp0_pdp_find(gsk, nla_get_u64(info->attrs[GTPA_TID]));
+               break;
+
+       case GTP_V1:
+               if (!info->attrs[GTPA_I_TEI]) {
+                       pctx = ERR_PTR(-EINVAL);
+                       break;
+               }
+               pctx = gtp1_pdp_find(gsk, nla_get_u64(info->attrs[GTPA_I_TEI]));
+               break;
+
+       default:
+               pctx = ERR_PTR(-EINVAL);
+               break;
+       }
+
+out_sock:
+       sockfd_put(sock);
+       return pctx;
+}
+
 static struct pdp_ctx *gtp_genl_find_pdp(struct sk_buff *skb,
                                         struct genl_info *info)
 {
        if (info->attrs[GTPA_LINK])
                return gtp_genl_find_pdp_by_link(skb, info);
+       else if (info->attrs[GTPA_FD])
+               return gtp_genl_find_pdp_by_socket(skb, info);
        else
                return ERR_PTR(-EINVAL);
 }
-- 
2.10.2