ceph/src/dpdk/lib/librte_ip_frag/rte_ipv4_reassembly.c

   1 /*-
   2  *   BSD LICENSE
   3  *
   4  *   Copyright(c) 2010-2014 Intel Corporation. All rights reserved.
   5  *   All rights reserved.
   6  *
   7  *   Redistribution and use in source and binary forms, with or without
   8  *   modification, are permitted provided that the following conditions
   9  *   are met:
  10  *
  11  *     * Redistributions of source code must retain the above copyright
  12  *       notice, this list of conditions and the following disclaimer.
  13  *     * Redistributions in binary form must reproduce the above copyright
  14  *       notice, this list of conditions and the following disclaimer in
  15  *       the documentation and/or other materials provided with the
  16  *       distribution.
  17  *     * Neither the name of Intel Corporation nor the names of its
  18  *       contributors may be used to endorse or promote products derived
  19  *       from this software without specific prior written permission.
  20  *
  21  *   THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
  22  *   "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
  23  *   LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR
  24  *   A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE COPYRIGHT
  25  *   OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT, INCIDENTAL,
  26  *   SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT NOT
  27  *   LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
  28  *   DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
  29  *   THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
  30  *   (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE
  31  *   OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
  32  */
  33
  34 #include <stddef.h>
  35
  36 #include <rte_debug.h>
  37
  38 #include "ip_frag_common.h"
  39
  40 /*
  41  * Reassemble fragments into one packet.
  42  */
  43 struct rte_mbuf *
  44 ipv4_frag_reassemble(struct ip_frag_pkt *fp)
  45 {
  46         struct ipv4_hdr *ip_hdr;
  47         struct rte_mbuf *m, *prev;
  48         uint32_t i, n, ofs, first_len;
  49         uint32_t curr_idx = 0;
  50
  51         first_len = fp->frags[IP_FIRST_FRAG_IDX].len;
  52         n = fp->last_idx - 1;
  53
  54         /*start from the last fragment. */
  55         m = fp->frags[IP_LAST_FRAG_IDX].mb;
  56         ofs = fp->frags[IP_LAST_FRAG_IDX].ofs;
  57         curr_idx = IP_LAST_FRAG_IDX;
  58
  59         while (ofs != first_len) {
  60
  61                 prev = m;
  62
  63                 for (i = n; i != IP_FIRST_FRAG_IDX && ofs != first_len; i--) {
  64
  65                         /* previous fragment found. */
  66                         if(fp->frags[i].ofs + fp->frags[i].len == ofs) {
  67
  68                                 /* adjust start of the last fragment data. */
  69                                 rte_pktmbuf_adj(m, (uint16_t)(m->l2_len + m->l3_len));
  70                                 rte_pktmbuf_chain(fp->frags[i].mb, m);
  71
  72                                 /* this mbuf should not be accessed directly */
  73                                 fp->frags[curr_idx].mb = NULL;
  74                                 curr_idx = i;
  75
  76                                 /* update our last fragment and offset. */
  77                                 m = fp->frags[i].mb;
  78                                 ofs = fp->frags[i].ofs;
  79                         }
  80                 }
  81
  82                 /* error - hole in the packet. */
  83                 if (m == prev) {
  84                         return NULL;
  85                 }
  86         }
  87
  88         /* chain with the first fragment. */
  89         rte_pktmbuf_adj(m, (uint16_t)(m->l2_len + m->l3_len));
  90         rte_pktmbuf_chain(fp->frags[IP_FIRST_FRAG_IDX].mb, m);
  91         m = fp->frags[IP_FIRST_FRAG_IDX].mb;
  92
  93         /* update mbuf fields for reassembled packet. */
  94         m->ol_flags |= PKT_TX_IP_CKSUM;
  95
  96         /* update ipv4 header for the reassmebled packet */
  97         ip_hdr = rte_pktmbuf_mtod_offset(m, struct ipv4_hdr *, m->l2_len);
  98
  99         ip_hdr->total_length = rte_cpu_to_be_16((uint16_t)(fp->total_size +
 100                 m->l3_len));
 101         ip_hdr->fragment_offset = (uint16_t)(ip_hdr->fragment_offset &
 102                 rte_cpu_to_be_16(IPV4_HDR_DF_FLAG));
 103         ip_hdr->hdr_checksum = 0;
 104
 105         return m;
 106 }
 107
 108 /*
 109  * Process new mbuf with fragment of IPV4 packet.
 110  * Incoming mbuf should have it's l2_len/l3_len fields setuped correclty.
 111  * @param tbl
 112  *   Table where to lookup/add the fragmented packet.
 113  * @param mb
 114  *   Incoming mbuf with IPV4 fragment.
 115  * @param tms
 116  *   Fragment arrival timestamp.
 117  * @param ip_hdr
 118  *   Pointer to the IPV4 header inside the fragment.
 119  * @return
 120  *   Pointer to mbuf for reassebled packet, or NULL if:
 121  *   - an error occured.
 122  *   - not all fragments of the packet are collected yet.
 123  */
 124 struct rte_mbuf *
 125 rte_ipv4_frag_reassemble_packet(struct rte_ip_frag_tbl *tbl,
 126                 struct rte_ip_frag_death_row *dr, struct rte_mbuf *mb, uint64_t tms,
 127                 struct ipv4_hdr *ip_hdr)
 128 {
 129         struct ip_frag_pkt *fp;
 130         struct ip_frag_key key;
 131         const unaligned_uint64_t *psd;
 132         uint16_t ip_len;
 133         uint16_t flag_offset, ip_ofs, ip_flag;
 134
 135         flag_offset = rte_be_to_cpu_16(ip_hdr->fragment_offset);
 136         ip_ofs = (uint16_t)(flag_offset & IPV4_HDR_OFFSET_MASK);
 137         ip_flag = (uint16_t)(flag_offset & IPV4_HDR_MF_FLAG);
 138
 139         psd = (unaligned_uint64_t *)&ip_hdr->src_addr;
 140         /* use first 8 bytes only */
 141         key.src_dst[0] = psd[0];
 142         key.id = ip_hdr->packet_id;
 143         key.key_len = IPV4_KEYLEN;
 144
 145         ip_ofs *= IPV4_HDR_OFFSET_UNITS;
 146         ip_len = (uint16_t)(rte_be_to_cpu_16(ip_hdr->total_length) -
 147                 mb->l3_len);
 148
 149         IP_FRAG_LOG(DEBUG, "%s:%d:\n"
 150                 "mbuf: %p, tms: %" PRIu64
 151                 ", key: <%" PRIx64 ", %#x>, ofs: %u, len: %u, flags: %#x\n"
 152                 "tbl: %p, max_cycles: %" PRIu64 ", entry_mask: %#x, "
 153                 "max_entries: %u, use_entries: %u\n\n",
 154                 __func__, __LINE__,
 155                 mb, tms, key.src_dst[0], key.id, ip_ofs, ip_len, ip_flag,
 156                 tbl, tbl->max_cycles, tbl->entry_mask, tbl->max_entries,
 157                 tbl->use_entries);
 158
 159         /* try to find/add entry into the fragment's table. */
 160         if ((fp = ip_frag_find(tbl, dr, &key, tms)) == NULL) {
 161                 IP_FRAG_MBUF2DR(dr, mb);
 162                 return NULL;
 163         }
 164
 165         IP_FRAG_LOG(DEBUG, "%s:%d:\n"
 166                 "tbl: %p, max_entries: %u, use_entries: %u\n"
 167                 "ipv4_frag_pkt: %p, key: <%" PRIx64 ", %#x>, start: %" PRIu64
 168                 ", total_size: %u, frag_size: %u, last_idx: %u\n\n",
 169                 __func__, __LINE__,
 170                 tbl, tbl->max_entries, tbl->use_entries,
 171                 fp, fp->key.src_dst[0], fp->key.id, fp->start,
 172                 fp->total_size, fp->frag_size, fp->last_idx);
 173
 174
 175         /* process the fragmented packet. */
 176         mb = ip_frag_process(fp, dr, mb, ip_ofs, ip_len, ip_flag);
 177         ip_frag_inuse(tbl, fp);
 178
 179         IP_FRAG_LOG(DEBUG, "%s:%d:\n"
 180                 "mbuf: %p\n"
 181                 "tbl: %p, max_entries: %u, use_entries: %u\n"
 182                 "ipv4_frag_pkt: %p, key: <%" PRIx64 ", %#x>, start: %" PRIu64
 183                 ", total_size: %u, frag_size: %u, last_idx: %u\n\n",
 184                 __func__, __LINE__, mb,
 185                 tbl, tbl->max_entries, tbl->use_entries,
 186                 fp, fp->key.src_dst[0], fp->key.id, fp->start,
 187                 fp->total_size, fp->frag_size, fp->last_idx);
 188
 189         return mb;
 190 }