xref: /dpdk/lib/gro/gro_tcp4.c (revision da7e701151ea8b742d4c38ace3e4fefd1b4507fc)
1 /* SPDX-License-Identifier: BSD-3-Clause
2  * Copyright(c) 2017 Intel Corporation
3  */
4 
5 #include <rte_malloc.h>
6 #include <rte_mbuf.h>
7 #include <rte_ethdev.h>
8 
9 #include "gro_tcp4.h"
10 #include "gro_tcp_internal.h"
11 
12 void *
13 gro_tcp4_tbl_create(uint16_t socket_id,
14 		uint16_t max_flow_num,
15 		uint16_t max_item_per_flow)
16 {
17 	struct gro_tcp4_tbl *tbl;
18 	size_t size;
19 	uint32_t entries_num, i;
20 
21 	entries_num = max_flow_num * max_item_per_flow;
22 	entries_num = RTE_MIN(entries_num, GRO_TCP4_TBL_MAX_ITEM_NUM);
23 
24 	if (entries_num == 0)
25 		return NULL;
26 
27 	tbl = rte_zmalloc_socket(__func__,
28 			sizeof(struct gro_tcp4_tbl),
29 			RTE_CACHE_LINE_SIZE,
30 			socket_id);
31 	if (tbl == NULL)
32 		return NULL;
33 
34 	size = sizeof(struct gro_tcp_item) * entries_num;
35 	tbl->items = rte_zmalloc_socket(__func__,
36 			size,
37 			RTE_CACHE_LINE_SIZE,
38 			socket_id);
39 	if (tbl->items == NULL) {
40 		rte_free(tbl);
41 		return NULL;
42 	}
43 	tbl->max_item_num = entries_num;
44 
45 	size = sizeof(struct gro_tcp4_flow) * entries_num;
46 	tbl->flows = rte_zmalloc_socket(__func__,
47 			size,
48 			RTE_CACHE_LINE_SIZE,
49 			socket_id);
50 	if (tbl->flows == NULL) {
51 		rte_free(tbl->items);
52 		rte_free(tbl);
53 		return NULL;
54 	}
55 	/* INVALID_ARRAY_INDEX indicates an empty flow */
56 	for (i = 0; i < entries_num; i++)
57 		tbl->flows[i].start_index = INVALID_ARRAY_INDEX;
58 	tbl->max_flow_num = entries_num;
59 
60 	return tbl;
61 }
62 
63 void
64 gro_tcp4_tbl_destroy(void *tbl)
65 {
66 	struct gro_tcp4_tbl *tcp_tbl = tbl;
67 
68 	if (tcp_tbl) {
69 		rte_free(tcp_tbl->items);
70 		rte_free(tcp_tbl->flows);
71 	}
72 	rte_free(tcp_tbl);
73 }
74 
75 static inline uint32_t
76 find_an_empty_flow(struct gro_tcp4_tbl *tbl)
77 {
78 	uint32_t i;
79 	uint32_t max_flow_num = tbl->max_flow_num;
80 
81 	for (i = 0; i < max_flow_num; i++)
82 		if (tbl->flows[i].start_index == INVALID_ARRAY_INDEX)
83 			return i;
84 	return INVALID_ARRAY_INDEX;
85 }
86 
87 static inline uint32_t
88 insert_new_flow(struct gro_tcp4_tbl *tbl,
89 		struct tcp4_flow_key *src,
90 		uint32_t item_idx)
91 {
92 	struct tcp4_flow_key *dst;
93 	uint32_t flow_idx;
94 
95 	flow_idx = find_an_empty_flow(tbl);
96 	if (unlikely(flow_idx == INVALID_ARRAY_INDEX))
97 		return INVALID_ARRAY_INDEX;
98 
99 	dst = &(tbl->flows[flow_idx].key);
100 
101 	ASSIGN_COMMON_TCP_KEY((&src->cmn_key), (&dst->cmn_key));
102 
103 	dst->ip_src_addr = src->ip_src_addr;
104 	dst->ip_dst_addr = src->ip_dst_addr;
105 
106 	tbl->flows[flow_idx].start_index = item_idx;
107 	tbl->flow_num++;
108 
109 	return flow_idx;
110 }
111 
112 int32_t
113 gro_tcp4_reassemble(struct rte_mbuf *pkt,
114 		struct gro_tcp4_tbl *tbl,
115 		uint64_t start_time)
116 {
117 	struct rte_ether_hdr *eth_hdr;
118 	struct rte_ipv4_hdr *ipv4_hdr;
119 	struct rte_tcp_hdr *tcp_hdr;
120 	uint32_t sent_seq;
121 	int32_t tcp_dl;
122 	uint16_t ip_id, hdr_len, frag_off, ip_tlen;
123 	uint8_t is_atomic;
124 
125 	struct tcp4_flow_key key;
126 	uint32_t item_idx;
127 	uint32_t i, max_flow_num, remaining_flow_num;
128 	uint8_t find;
129 
130 	/*
131 	 * Don't process the packet whose TCP header length is greater
132 	 * than 60 bytes or less than 20 bytes.
133 	 */
134 	if (unlikely(INVALID_TCP_HDRLEN(pkt->l4_len)))
135 		return -1;
136 
137 	eth_hdr = rte_pktmbuf_mtod(pkt, struct rte_ether_hdr *);
138 	ipv4_hdr = (struct rte_ipv4_hdr *)((char *)eth_hdr + pkt->l2_len);
139 	tcp_hdr = (struct rte_tcp_hdr *)((char *)ipv4_hdr + pkt->l3_len);
140 	hdr_len = pkt->l2_len + pkt->l3_len + pkt->l4_len;
141 
142 	/*
143 	 * Don't process the packet which has FIN, SYN, RST, PSH, URG, ECE
144 	 * or CWR set.
145 	 */
146 	if (tcp_hdr->tcp_flags != RTE_TCP_ACK_FLAG)
147 		return -1;
148 
149 	/* trim the tail padding bytes */
150 	ip_tlen = rte_be_to_cpu_16(ipv4_hdr->total_length);
151 	if (pkt->pkt_len > (uint32_t)(ip_tlen + pkt->l2_len))
152 		rte_pktmbuf_trim(pkt, pkt->pkt_len - ip_tlen - pkt->l2_len);
153 
154 	/*
155 	 * Don't process the packet whose payload length is less than or
156 	 * equal to 0.
157 	 */
158 	tcp_dl = pkt->pkt_len - hdr_len;
159 	if (tcp_dl <= 0)
160 		return -1;
161 
162 	rte_ether_addr_copy(&(eth_hdr->src_addr), &(key.cmn_key.eth_saddr));
163 	rte_ether_addr_copy(&(eth_hdr->dst_addr), &(key.cmn_key.eth_daddr));
164 	key.ip_src_addr = ipv4_hdr->src_addr;
165 	key.ip_dst_addr = ipv4_hdr->dst_addr;
166 	key.cmn_key.src_port = tcp_hdr->src_port;
167 	key.cmn_key.dst_port = tcp_hdr->dst_port;
168 	key.cmn_key.recv_ack = tcp_hdr->recv_ack;
169 
170 	/*
171 	 * Save IPv4 ID for the packet whose DF bit is 0. For the packet
172 	 * whose DF bit is 1, IPv4 ID is ignored.
173 	 */
174 	frag_off = rte_be_to_cpu_16(ipv4_hdr->fragment_offset);
175 	is_atomic = (frag_off & RTE_IPV4_HDR_DF_FLAG) == RTE_IPV4_HDR_DF_FLAG;
176 	ip_id = is_atomic ? 0 : rte_be_to_cpu_16(ipv4_hdr->packet_id);
177 
178 	/* Search for a matched flow. */
179 	max_flow_num = tbl->max_flow_num;
180 	remaining_flow_num = tbl->flow_num;
181 	find = 0;
182 	for (i = 0; i < max_flow_num && remaining_flow_num; i++) {
183 		if (tbl->flows[i].start_index != INVALID_ARRAY_INDEX) {
184 			if (is_same_tcp4_flow(tbl->flows[i].key, key)) {
185 				find = 1;
186 				break;
187 			}
188 			remaining_flow_num--;
189 		}
190 	}
191 
192 	if (find == 0) {
193 		sent_seq = rte_be_to_cpu_32(tcp_hdr->sent_seq);
194 		item_idx = insert_new_tcp_item(pkt, tbl->items, &tbl->item_num,
195 						tbl->max_item_num, start_time,
196 						INVALID_ARRAY_INDEX, sent_seq, ip_id,
197 						is_atomic);
198 		if (item_idx == INVALID_ARRAY_INDEX)
199 			return -1;
200 		if (insert_new_flow(tbl, &key, item_idx) ==
201 			INVALID_ARRAY_INDEX) {
202 			/*
203 			 * Fail to insert a new flow, so delete the
204 			 * stored packet.
205 			*/
206 			delete_tcp_item(tbl->items, item_idx, &tbl->item_num, INVALID_ARRAY_INDEX);
207 			return -1;
208 		}
209 		return 0;
210 	}
211 
212 	return process_tcp_item(pkt, tcp_hdr, tcp_dl, tbl->items, tbl->flows[i].start_index,
213 						&tbl->item_num, tbl->max_item_num,
214 						ip_id, is_atomic, start_time);
215 }
216 
217 /*
218  * update the packet length for the flushed packet.
219  */
220 static inline void
221 update_header(struct gro_tcp_item *item)
222 {
223 	struct rte_ipv4_hdr *ipv4_hdr;
224 	struct rte_mbuf *pkt = item->firstseg;
225 
226 	ipv4_hdr = (struct rte_ipv4_hdr *)(rte_pktmbuf_mtod(pkt, char *) +
227 			pkt->l2_len);
228 	ipv4_hdr->total_length = rte_cpu_to_be_16(pkt->pkt_len -
229 			pkt->l2_len);
230 }
231 
232 uint16_t
233 gro_tcp4_tbl_timeout_flush(struct gro_tcp4_tbl *tbl,
234 		uint64_t flush_timestamp,
235 		struct rte_mbuf **out,
236 		uint16_t nb_out)
237 {
238 	uint16_t k = 0;
239 	uint32_t i, j;
240 	uint32_t max_flow_num = tbl->max_flow_num;
241 
242 	for (i = 0; i < max_flow_num; i++) {
243 		if (unlikely(tbl->flow_num == 0))
244 			return k;
245 
246 		j = tbl->flows[i].start_index;
247 		while (j != INVALID_ARRAY_INDEX) {
248 			if (tbl->items[j].start_time <= flush_timestamp) {
249 				out[k++] = tbl->items[j].firstseg;
250 				if (tbl->items[j].nb_merged > 1)
251 					update_header(&(tbl->items[j]));
252 				/*
253 				 * Delete the packet and get the next
254 				 * packet in the flow.
255 				 */
256 				j = delete_tcp_item(tbl->items, j,
257 							&tbl->item_num, INVALID_ARRAY_INDEX);
258 				tbl->flows[i].start_index = j;
259 				if (j == INVALID_ARRAY_INDEX)
260 					tbl->flow_num--;
261 
262 				if (unlikely(k == nb_out))
263 					return k;
264 			} else
265 				/*
266 				 * The left packets in this flow won't be
267 				 * timeout. Go to check other flows.
268 				 */
269 				break;
270 		}
271 	}
272 	return k;
273 }
274 
275 uint32_t
276 gro_tcp4_tbl_pkt_count(void *tbl)
277 {
278 	struct gro_tcp4_tbl *gro_tbl = tbl;
279 
280 	if (gro_tbl)
281 		return gro_tbl->item_num;
282 
283 	return 0;
284 }
285