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/* SPDX-License-Identifier: BSD-3-Clause
* Copyright (c) 2017-2018 Linaro Limited
*/
/** @cond _ODP_HIDE_FROM_DOXYGEN_ */
#include <stdio.h>
#include <assert.h>
#include "odp_ipfragreass_ip.h"
#include "odp_ipfragreass_fragment.h"
int fragment_ipv4_packet(odp_packet_t orig_packet, odp_packet_t *out,
int *out_len)
{
int fragments = 0;
odp_bool_t first_fragment = 1;
odph_ipv4hdr_t *orig_header = odp_packet_data(orig_packet);
uint32_t header_len = ipv4hdr_ihl(*orig_header);
uint32_t orig_len = odp_packet_len(orig_packet);
uint32_t bytes_remaining = orig_len - header_len;
uint32_t frag_offset = 0;
odp_packet_t frag = orig_packet;
odp_packet_t rest = ODP_PACKET_INVALID;
if (bytes_remaining <= MTU)
return -1;
/*
* The main fragmentation loop (continue until all bytes from the
* original payload have been assigned to a fragment)
*/
while (bytes_remaining) {
odph_ipv4hdr_t *header;
uint32_t frag_len;
frag_len = (bytes_remaining > MTU ? (MTU + header_len)
: (bytes_remaining
+ header_len));
bytes_remaining -= (frag_len - header_len);
if (bytes_remaining) {
uint32_t split_point;
int split_success;
split_point = first_fragment ? (frag_len)
: (frag_len - header_len);
split_success = odp_packet_split(&frag, split_point,
&rest);
if (split_success < 0) {
fprintf(stderr,
"ERROR: odp_packet_split\n");
return -1;
} else if (first_fragment && split_success > 0) {
orig_header = odp_packet_data(frag);
}
}
/* Add a header to the packet if necessary */
if (first_fragment) {
first_fragment = 0;
} else {
if (odp_packet_extend_head(&frag, header_len, NULL,
NULL) < 0) {
fprintf(stderr,
"ERROR: odp_packet_extend_head\n");
return -1;
}
if (odp_packet_copy_from_mem(frag, 0, header_len,
orig_header)) {
fprintf(stderr,
"ERROR: odp_packet_copy_from_mem\n");
return -1;
}
}
/* Update the header */
header = odp_packet_data(frag);
ipv4hdr_set_more_fragments(header, bytes_remaining != 0);
header->tot_len = odp_cpu_to_be_16(frag_len);
ipv4hdr_set_fragment_offset_oct(header, (frag_offset / 8));
assert((bytes_remaining == 0) ||
(odp_packet_len(frag) == (MTU + header_len)));
assert((bytes_remaining != 0) ||
(ipv4hdr_reass_payload_len(*header) + header_len
== orig_len));
odp_packet_l3_offset_set(frag, 0);
header->chksum = 0;
odph_ipv4_csum_update(frag);
out[fragments++] = frag;
frag = rest;
frag_offset += (frag_len - header_len);
}
if (out_len)
*out_len = fragments;
return 0;
}
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