LXR dpdk/lib/ip_frag/rte_ipv6

   1/* SPDX-License-Identifier: BSD-3-Clause
   2 * Copyright(c) 2010-2014 Intel Corporation
   3 */
   4
   5#include <stddef.h>
   6#include <errno.h>
   7
   8#include <rte_memcpy.h>
   9
  10#include "ip_frag_common.h"
  11
  12/**
  13 * @file
  14 * RTE IPv6 Fragmentation
  15 *
  16 * Implementation of IPv6 fragmentation.
  17 *
  18 */
  19
  20static inline void
  21__fill_ipv6hdr_frag(struct rte_ipv6_hdr *dst,
  22                const struct rte_ipv6_hdr *src, uint16_t len, uint16_t fofs,
  23                uint32_t mf)
  24{
  25        struct rte_ipv6_fragment_ext *fh;
  26
  27        rte_memcpy(dst, src, sizeof(*dst));
  28        dst->payload_len = rte_cpu_to_be_16(len);
  29        dst->proto = IPPROTO_FRAGMENT;
  30
  31        fh = (struct rte_ipv6_fragment_ext *) ++dst;
  32        fh->next_header = src->proto;
  33        fh->reserved = 0;
  34        fh->frag_data = rte_cpu_to_be_16(RTE_IPV6_SET_FRAG_DATA(fofs, mf));
  35        fh->id = 0;
  36}
  37
  38static inline void
  39__free_fragments(struct rte_mbuf *mb[], uint32_t num)
  40{
  41        uint32_t i;
  42        for (i = 0; i < num; i++)
  43                rte_pktmbuf_free(mb[i]);
  44}
  45
  46/**
  47 * IPv6 fragmentation.
  48 *
  49 * This function implements the fragmentation of IPv6 packets.
  50 *
  51 * @param pkt_in
  52 *   The input packet.
  53 * @param pkts_out
  54 *   Array storing the output fragments.
  55 * @param mtu_size
  56 *   Size in bytes of the Maximum Transfer Unit (MTU) for the outgoing IPv6
  57 *   datagrams. This value includes the size of the IPv6 header.
  58 * @param pool_direct
  59 *   MBUF pool used for allocating direct buffers for the output fragments.
  60 * @param pool_indirect
  61 *   MBUF pool used for allocating indirect buffers for the output fragments.
  62 * @return
  63 *   Upon successful completion - number of output fragments placed
  64 *   in the pkts_out array.
  65 *   Otherwise - (-1) * <errno>.
  66 */
  67int32_t
  68rte_ipv6_fragment_packet(struct rte_mbuf *pkt_in,
  69        struct rte_mbuf **pkts_out,
  70        uint16_t nb_pkts_out,
  71        uint16_t mtu_size,
  72        struct rte_mempool *pool_direct,
  73        struct rte_mempool *pool_indirect)
  74{
  75        struct rte_mbuf *in_seg = NULL;
  76        struct rte_ipv6_hdr *in_hdr;
  77        uint32_t out_pkt_pos, in_seg_data_pos;
  78        uint32_t more_in_segs;
  79        uint16_t fragment_offset, frag_size;
  80        uint64_t frag_bytes_remaining;
  81
  82        /*
  83         * Formal parameter checking.
  84         */
  85        if (unlikely(pkt_in == NULL) || unlikely(pkts_out == NULL) ||
  86            unlikely(nb_pkts_out == 0) ||
  87            unlikely(pool_direct == NULL) || unlikely(pool_indirect == NULL) ||
  88            unlikely(mtu_size < RTE_IPV6_MIN_MTU))
  89                return -EINVAL;
  90
  91        /*
  92         * Ensure the IP payload length of all fragments (except the
  93         * last fragment) are a multiple of 8 bytes per RFC2460.
  94         */
  95
  96        frag_size = mtu_size - sizeof(struct rte_ipv6_hdr) -
  97                sizeof(struct rte_ipv6_fragment_ext);
  98        frag_size = RTE_ALIGN_FLOOR(frag_size, RTE_IPV6_EHDR_FO_ALIGN);
  99
 100        /* Check that pkts_out is big enough to hold all fragments */
 101        if (unlikely (frag_size * nb_pkts_out <
 102            (uint16_t)(pkt_in->pkt_len - sizeof(struct rte_ipv6_hdr))))
 103                return -EINVAL;
 104
 105        in_hdr = rte_pktmbuf_mtod(pkt_in, struct rte_ipv6_hdr *);
 106
 107        in_seg = pkt_in;
 108        in_seg_data_pos = sizeof(struct rte_ipv6_hdr);
 109        out_pkt_pos = 0;
 110        fragment_offset = 0;
 111
 112        more_in_segs = 1;
 113        while (likely(more_in_segs)) {
 114                struct rte_mbuf *out_pkt = NULL, *out_seg_prev = NULL;
 115                uint32_t more_out_segs;
 116                struct rte_ipv6_hdr *out_hdr;
 117
 118                /* Allocate direct buffer */
 119                out_pkt = rte_pktmbuf_alloc(pool_direct);
 120                if (unlikely(out_pkt == NULL)) {
 121                        __free_fragments(pkts_out, out_pkt_pos);
 122                        return -ENOMEM;
 123                }
 124
 125                /* Reserve space for the IP header that will be built later */
 126                out_pkt->data_len = sizeof(struct rte_ipv6_hdr) +
 127                        sizeof(struct rte_ipv6_fragment_ext);
 128                out_pkt->pkt_len  = sizeof(struct rte_ipv6_hdr) +
 129                        sizeof(struct rte_ipv6_fragment_ext);
 130                frag_bytes_remaining = frag_size;
 131
 132                out_seg_prev = out_pkt;
 133                more_out_segs = 1;
 134                while (likely(more_out_segs && more_in_segs)) {
 135                        struct rte_mbuf *out_seg = NULL;
 136                        uint32_t len;
 137
 138                        /* Allocate indirect buffer */
 139                        out_seg = rte_pktmbuf_alloc(pool_indirect);
 140                        if (unlikely(out_seg == NULL)) {
 141                                rte_pktmbuf_free(out_pkt);
 142                                __free_fragments(pkts_out, out_pkt_pos);
 143                                return -ENOMEM;
 144                        }
 145                        out_seg_prev->next = out_seg;
 146                        out_seg_prev = out_seg;
 147
 148                        /* Prepare indirect buffer */
 149                        rte_pktmbuf_attach(out_seg, in_seg);
 150                        len = frag_bytes_remaining;
 151                        if (len > (in_seg->data_len - in_seg_data_pos)) {
 152                                len = in_seg->data_len - in_seg_data_pos;
 153                        }
 154                        out_seg->data_off = in_seg->data_off + in_seg_data_pos;
 155                        out_seg->data_len = (uint16_t)len;
 156                        out_pkt->pkt_len = (uint16_t)(len +
 157                            out_pkt->pkt_len);
 158                        out_pkt->nb_segs += 1;
 159                        in_seg_data_pos += len;
 160                        frag_bytes_remaining -= len;
 161
 162                        /* Current output packet (i.e. fragment) done ? */
 163                        if (unlikely(frag_bytes_remaining == 0))
 164                                more_out_segs = 0;
 165
 166                        /* Current input segment done ? */
 167                        if (unlikely(in_seg_data_pos == in_seg->data_len)) {
 168                                in_seg = in_seg->next;
 169                                in_seg_data_pos = 0;
 170
 171                                if (unlikely(in_seg == NULL)) {
 172                                        more_in_segs = 0;
 173                                }
 174                        }
 175                }
 176
 177                /* Build the IP header */
 178
 179                out_hdr = rte_pktmbuf_mtod(out_pkt, struct rte_ipv6_hdr *);
 180
 181                __fill_ipv6hdr_frag(out_hdr, in_hdr,
 182                    (uint16_t) out_pkt->pkt_len - sizeof(struct rte_ipv6_hdr),
 183                    fragment_offset, more_in_segs);
 184
 185                fragment_offset = (uint16_t)(fragment_offset +
 186                    out_pkt->pkt_len - sizeof(struct rte_ipv6_hdr)
 187                        - sizeof(struct rte_ipv6_fragment_ext));
 188
 189                /* Write the fragment to the output list */
 190                pkts_out[out_pkt_pos] = out_pkt;
 191                out_pkt_pos ++;
 192        }
 193
 194        return out_pkt_pos;
 195}
 196