dccp: Support for Mandatory options
Support for Mandatory options is provided by this patch, which will
be used by subsequent feature-negotiation patches.
Signed-off-by: Gerrit Renker <gerrit@erg.abdn.ac.uk>
Acked-by: Ian McDonald <ian.mcdonald@jandi.co.nz>
Acked-by: Arnaldo Carvalho de Melo <acme@redhat.com>
Signed-off-by: David S. Miller <davem@davemloft.net>
diff --git a/net/dccp/feat.h b/net/dccp/feat.h
index a8ab9e1..f8e4878 100644
--- a/net/dccp/feat.h
+++ b/net/dccp/feat.h
@@ -139,4 +139,6 @@
extern void dccp_encode_value_var(const u64 value, u8 *to, const u8 len);
extern u64 dccp_decode_value_var(const u8 *bf, const u8 len);
+
+extern int dccp_insert_option_mandatory(struct sk_buff *skb);
#endif /* _DCCP_FEAT_H */
diff --git a/net/dccp/options.c b/net/dccp/options.c
index 9cb0ff8..676d530 100644
--- a/net/dccp/options.c
+++ b/net/dccp/options.c
@@ -467,6 +467,21 @@
return 0;
}
+/**
+ * dccp_insert_option_mandatory - Mandatory option (5.8.2)
+ * Note that since we are using skb_push, this function needs to be called
+ * _after_ inserting the option it is supposed to influence (stack order).
+ */
+int dccp_insert_option_mandatory(struct sk_buff *skb)
+{
+ if (DCCP_SKB_CB(skb)->dccpd_opt_len >= DCCP_MAX_OPT_LEN)
+ return -1;
+
+ DCCP_SKB_CB(skb)->dccpd_opt_len++;
+ *skb_push(skb, 1) = DCCPO_MANDATORY;
+ return 0;
+}
+
static int dccp_insert_feat_opt(struct sk_buff *skb, u8 type, u8 feat,
u8 *val, u8 len)
{