/*
* Copyright (c) 2015 Cisco and/or its affiliates.
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
* You may obtain a copy of the License at:
*
* http://www.apache.org/licenses/LICENSE-2.0
*
* Unless required by applicable law or agreed to in writing, software
* distributed under the License is distributed on an "AS IS" BASIS,
* WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
* See the License for the specific language governing permissions and
* limitations under the License.
*/
#ifndef __ESP_H__
#define __ESP_H__
#include <vnet/ip/ip.h>
#include <vnet/crypto/crypto.h>
#include <vnet/ipsec/ipsec.h>
typedef struct
{
union
{
u32 spi;
u8 spi_bytes[4];
};
u32 seq;
u8 data[0];
} esp_header_t;
typedef struct
{
u8 pad_length;
u8 next_header;
} esp_footer_t;
/* *INDENT-OFF* */
typedef CLIB_PACKED (struct {
ip4_header_t ip4;
esp_header_t esp;
}) ip4_and_esp_header_t;
/* *INDENT-ON* */
/* *INDENT-OFF* */
typedef CLIB_PACKED (struct {
ip4_header_t ip4;
udp_header_t udp;
esp_header_t esp;
}) ip4_and_udp_and_esp_header_t;
/* *INDENT-ON* */
/* *INDENT-OFF* */
typedef CLIB_PACKED (struct {
ip6_header_t ip6;
esp_header_t esp;
}) ip6_and_esp_header_t;
/* *INDENT-ON* */
/**
* AES GCM Additional Authentication data
*/
typedef struct esp_aead_t_
{
/**
* for GCM: when using ESN it's:
* SPI, seq-hi, seg-low
* else
* SPI, seq-low
*/
u32 data[3];
} __clib_packed esp_aead_t;
#define ESP_SEQ_MAX (4294967295UL)
#define ESP_MAX_BLOCK_SIZE (16)
#define ESP_MAX_IV_SIZE (16)
#define ESP_MAX_ICV_SIZE (32)
u8 *format_esp_header (u8 * s, va_list * args);
/* TODO seq increment should be atomic to be accessed by multiple workers */
always_inline int
esp_seq_advance (ipsec_sa_t * sa)
{
if (PREDICT_TRUE (ipsec_sa_is_set_USE_ESN (sa)))
{
if (PREDICT_FALSE (sa->seq == ESP_SEQ_MAX))
{
if (PREDICT_FALSE (ipsec_sa_is_set_USE_ANTI_REPLAY (sa) &&
sa->seq_hi == ESP_SEQ_MAX))
return 1;
sa->seq_hi++;
}
sa->seq++;
}
else
{
if (PREDICT_FALSE (ipsec_sa_is_set_USE_ANTI_REPLAY (sa) &&
sa->seq == ESP_SEQ_MAX))
return 1;
sa->seq++;
}
return 0;
}
always_inline u16
esp_aad_fill (u8 * data, const esp_header_t * esp, const ipsec_sa_t * sa)
{
esp_aead_t *aad;
aad = (esp_aead_t *) data;
aad->data[0] =