1 /* SPDX-License-Identifier: BSD-3-Clause
2 * Copyright(c) 2010-2014 Intel Corporation
7 #include <rte_memcpy.h>
9 #include "ip_frag_common.h"
15 * Implementation of IPv6 reassembly.
20 ip_frag_memmove(char *dst, char *src, int len)
24 /* go backwards to make sure we don't overwrite anything important */
25 for (i = len - 1; i >= 0; i--)
30 * Reassemble fragments into one packet.
33 ipv6_frag_reassemble(struct ip_frag_pkt *fp)
35 struct ipv6_hdr *ip_hdr;
36 struct ipv6_extension_fragment *frag_hdr;
37 struct rte_mbuf *m, *prev;
38 uint32_t i, n, ofs, first_len;
39 uint32_t last_len, move_len, payload_len;
40 uint32_t curr_idx = 0;
42 first_len = fp->frags[IP_FIRST_FRAG_IDX].len;
45 /*start from the last fragment. */
46 m = fp->frags[IP_LAST_FRAG_IDX].mb;
47 ofs = fp->frags[IP_LAST_FRAG_IDX].ofs;
48 last_len = fp->frags[IP_LAST_FRAG_IDX].len;
49 curr_idx = IP_LAST_FRAG_IDX;
51 payload_len = ofs + last_len;
53 while (ofs != first_len) {
57 for (i = n; i != IP_FIRST_FRAG_IDX && ofs != first_len; i--) {
59 /* previous fragment found. */
60 if (fp->frags[i].ofs + fp->frags[i].len == ofs) {
62 /* adjust start of the last fragment data. */
63 rte_pktmbuf_adj(m, (uint16_t)(m->l2_len + m->l3_len));
64 rte_pktmbuf_chain(fp->frags[i].mb, m);
66 /* this mbuf should not be accessed directly */
67 fp->frags[curr_idx].mb = NULL;
70 /* update our last fragment and offset. */
72 ofs = fp->frags[i].ofs;
76 /* error - hole in the packet. */
82 /* chain with the first fragment. */
83 rte_pktmbuf_adj(m, (uint16_t)(m->l2_len + m->l3_len));
84 rte_pktmbuf_chain(fp->frags[IP_FIRST_FRAG_IDX].mb, m);
85 m = fp->frags[IP_FIRST_FRAG_IDX].mb;
87 /* update mbuf fields for reassembled packet. */
88 m->ol_flags |= PKT_TX_IP_CKSUM;
90 /* update ipv6 header for the reassembled datagram */
91 ip_hdr = rte_pktmbuf_mtod_offset(m, struct ipv6_hdr *, m->l2_len);
93 ip_hdr->payload_len = rte_cpu_to_be_16(payload_len);
96 * remove fragmentation header. note that per RFC2460, we need to update
97 * the last non-fragmentable header with the "next header" field to contain
98 * type of the first fragmentable header, but we currently don't support
99 * other headers, so we assume there are no other headers and thus update
100 * the main IPv6 header instead.
102 move_len = m->l2_len + m->l3_len - sizeof(*frag_hdr);
103 frag_hdr = (struct ipv6_extension_fragment *) (ip_hdr + 1);
104 ip_hdr->proto = frag_hdr->next_header;
106 ip_frag_memmove(rte_pktmbuf_mtod_offset(m, char *, sizeof(*frag_hdr)),
107 rte_pktmbuf_mtod(m, char*), move_len);
109 rte_pktmbuf_adj(m, sizeof(*frag_hdr));
115 * Process new mbuf with fragment of IPV6 datagram.
116 * Incoming mbuf should have its l2_len/l3_len fields setup correctly.
118 * Table where to lookup/add the fragmented packet.
120 * Incoming mbuf with IPV6 fragment.
122 * Fragment arrival timestamp.
124 * Pointer to the IPV6 header.
126 * Pointer to the IPV6 fragment extension header.
128 * Pointer to mbuf for reassembled packet, or NULL if:
129 * - an error occurred.
130 * - not all fragments of the packet are collected yet.
132 #define MORE_FRAGS(x) (((x) & 0x100) >> 8)
133 #define FRAG_OFFSET(x) (rte_cpu_to_be_16(x) >> 3)
135 rte_ipv6_frag_reassemble_packet(struct rte_ip_frag_tbl *tbl,
136 struct rte_ip_frag_death_row *dr, struct rte_mbuf *mb, uint64_t tms,
137 struct ipv6_hdr *ip_hdr, struct ipv6_extension_fragment *frag_hdr)
139 struct ip_frag_pkt *fp;
140 struct ip_frag_key key;
141 uint16_t ip_len, ip_ofs;
143 rte_memcpy(&key.src_dst[0], ip_hdr->src_addr, 16);
144 rte_memcpy(&key.src_dst[2], ip_hdr->dst_addr, 16);
146 key.id = frag_hdr->id;
147 key.key_len = IPV6_KEYLEN;
149 ip_ofs = FRAG_OFFSET(frag_hdr->frag_data) * 8;
152 * as per RFC2460, payload length contains all extension headers as well.
153 * since we don't support anything but frag headers, this is what we remove
154 * from the payload len.
156 ip_len = rte_be_to_cpu_16(ip_hdr->payload_len) - sizeof(*frag_hdr);
158 IP_FRAG_LOG(DEBUG, "%s:%d:\n"
159 "mbuf: %p, tms: %" PRIu64
160 ", key: <" IPv6_KEY_BYTES_FMT ", %#x>, ofs: %u, len: %u, flags: %#x\n"
161 "tbl: %p, max_cycles: %" PRIu64 ", entry_mask: %#x, "
162 "max_entries: %u, use_entries: %u\n\n",
164 mb, tms, IPv6_KEY_BYTES(key.src_dst), key.id, ip_ofs, ip_len,
165 RTE_IPV6_GET_MF(frag_hdr->frag_data),
166 tbl, tbl->max_cycles, tbl->entry_mask, tbl->max_entries,
169 /* try to find/add entry into the fragment's table. */
170 fp = ip_frag_find(tbl, dr, &key, tms);
172 IP_FRAG_MBUF2DR(dr, mb);
176 IP_FRAG_LOG(DEBUG, "%s:%d:\n"
177 "tbl: %p, max_entries: %u, use_entries: %u\n"
178 "ipv6_frag_pkt: %p, key: <" IPv6_KEY_BYTES_FMT ", %#x>, start: %" PRIu64
179 ", total_size: %u, frag_size: %u, last_idx: %u\n\n",
181 tbl, tbl->max_entries, tbl->use_entries,
182 fp, IPv6_KEY_BYTES(fp->key.src_dst), fp->key.id, fp->start,
183 fp->total_size, fp->frag_size, fp->last_idx);
186 /* process the fragmented packet. */
187 mb = ip_frag_process(fp, dr, mb, ip_ofs, ip_len,
188 MORE_FRAGS(frag_hdr->frag_data));
189 ip_frag_inuse(tbl, fp);
191 IP_FRAG_LOG(DEBUG, "%s:%d:\n"
193 "tbl: %p, max_entries: %u, use_entries: %u\n"
194 "ipv6_frag_pkt: %p, key: <" IPv6_KEY_BYTES_FMT ", %#x>, start: %" PRIu64
195 ", total_size: %u, frag_size: %u, last_idx: %u\n\n",
196 __func__, __LINE__, mb,
197 tbl, tbl->max_entries, tbl->use_entries,
198 fp, IPv6_KEY_BYTES(fp->key.src_dst), fp->key.id, fp->start,
199 fp->total_size, fp->frag_size, fp->last_idx);