2025-01-13, 10:31:27 +0100, Antonio Quartulli wrote: > +/** > + * ovpn_opcode_from_skb - extract OP code from skb at specified offset > + * @skb: the packet to extract the OP code from > + * @offset: the offset in the data buffer where the OP code is located > + * > + * Note: this function assumes that the skb head was pulled enough > + * to access the first byte. nit: "first byte" > + * > + * Return: the OP code > + */ > +static inline u8 ovpn_opcode_from_skb(const struct sk_buff *skb, u16 offset) > +{ > + u32 opcode = be32_to_cpu(*(__be32 *)(skb->data + offset)); vs 4 bytes actually read? Also for ovpn_key_id_from_skb introduced in another patch. I guess that's a consequence of switching to those FIELD macros. > +/** > + * ovpn_udp_encap_recv - Start processing a received UDP packet. > + * @sk: socket over which the packet was received > + * @skb: the received packet > + * > + * If the first byte of the payload is DATA_V2, the packet is further processed, > + * otherwise it is forwarded to the UDP stack for delivery to user space. nit: not consistent with the implementation in the case of DATA_V1 packets > + * Return: > + * 0 if skb was consumed or dropped > + * >0 if skb should be passed up to userspace as UDP (packet not consumed) > + * <0 if skb should be resubmitted as proto -N (packet not consumed) > + */ > +static int ovpn_udp_encap_recv(struct sock *sk, struct sk_buff *skb) > +{ [...] > + opcode = ovpn_opcode_from_skb(skb, sizeof(struct udphdr)); > + if (unlikely(opcode != OVPN_DATA_V2)) { > + /* DATA_V1 is not supported */ > + if (opcode == OVPN_DATA_V1) > + goto drop; -- Sabrina