packet.h

 
#ifndef KERNEL_NET_PACKET_H
#define KERNEL_NET_PACKET_H
 
#include <kernel/error.h>
#include <kernel/types.h>
 
#include <libalgo/queue.h>
#include <utils/math.h>
 
struct ethernet_device;
/* L2 headers */
struct ethernet_header;
/* L3 headers */
struct ipv4_header;
struct arp_header;
 
struct packet {
    size_t allocated_size; 
    size_t packet_size;    
    size_t popped;         
 
    struct ethernet_device *netdev;
 
    union {
        void *raw;
        struct ethernet_header *ethernet;
    } l2;
 
    union {
        void *raw;
        struct ipv4_header *ipv4;
        struct arp_header *arp;
    } l3;
 
    void *payload;
 
    node_t rx_this; 
};
 
#define PACKET_ALIGN (sizeof(uint64_t))
 
struct packet *packet_new(size_t packet_size);
 
struct packet *packet_clone(const struct packet *packet);
 
void packet_free(struct packet *packet);
 
error_t packet_send(struct packet *packet);
 
static inline void *packet_start(const struct packet *packet)
{
    return ((void *)packet) + align_up(sizeof(struct packet), PACKET_ALIGN);
}
 
static inline size_t packet_size(const struct packet *packet)
{
    return packet->packet_size;
}
 
static inline size_t packet_read_size(const struct packet *packet)
{
    return packet->packet_size - packet->popped;
}
 
static inline void *packet_end(const struct packet *packet)
{
    return packet_start(packet) + packet_size(packet);
}
 
error_t packet_put(struct packet *packet, const void *data, size_t size);
 
size_t packet_peek(struct packet *packet, void *data, size_t size);
 
size_t packet_pop(struct packet *packet, void *data, size_t size);
 
#define packet_put_literal(packet, data) packet_put(packet, &data, sizeof(data))
 
#define packet_peek_literal(packet, data) \
    packet_peek(packet, &data, sizeof(data))
 
#define packet_pop_literal(packet, data) packet_pop(packet, &data, sizeof(data))
 
static inline void packet_mark_l2_start(struct packet *packet)
{
    packet->l2.raw = packet_end(packet);
}
 
static inline void packet_set_l2_size(struct packet *packet, size_t size)
{
    packet->l3.raw = packet->l2.raw + size;
}
 
static inline void packet_mark_l3_start(struct packet *packet)
{
    packet->l3.raw = packet_end(packet);
}
 
static inline void packet_set_l3_size(struct packet *packet, size_t size)
{
    packet->payload = packet->l3.raw + size;
}
 
static inline void *packet_payload(const struct packet *packet)
{
    return packet->payload;
}
 
static inline size_t packet_header_size(const struct packet *packet)
{
    return packet->payload -
           (((void *)packet) + align_up(sizeof(struct packet), PACKET_ALIGN));
}
 
static inline size_t packet_payload_size(const struct packet *packet)
{
    return packet_end(packet) - packet->payload;
}
 
#endif /* KERNEL_NET_PACKET_H */