summaryrefslogtreecommitdiff
path: root/lib/librte_ip_frag/rte_ip_frag.h
blob: b24badee9f9ef398f1f48cc9057aa26a89c71817 (plain)
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
/* SPDX-License-Identifier: BSD-3-Clause
 * Copyright(c) 2010-2014 Intel Corporation
 */

#ifndef _RTE_IP_FRAG_H_
#define _RTE_IP_FRAG_H_

/**
 * @file
 * RTE IP Fragmentation and Reassembly
 *
 * Implementation of IP packet fragmentation and reassembly.
 */

#ifdef __cplusplus
extern "C" {
#endif

#include <stdint.h>
#include <stdio.h>

#include <rte_malloc.h>
#include <rte_memory.h>
#include <rte_ip.h>
#include <rte_byteorder.h>

struct rte_mbuf;

enum {
	IP_LAST_FRAG_IDX,    /**< index of last fragment */
	IP_FIRST_FRAG_IDX,   /**< index of first fragment */
	IP_MIN_FRAG_NUM,     /**< minimum number of fragments */
	IP_MAX_FRAG_NUM = RTE_LIBRTE_IP_FRAG_MAX_FRAG,
	/**< maximum number of fragments per packet */
};

/** @internal fragmented mbuf */
struct ip_frag {
	uint16_t ofs;          /**< offset into the packet */
	uint16_t len;          /**< length of fragment */
	struct rte_mbuf *mb;   /**< fragment mbuf */
};

/** @internal <src addr, dst_addr, id> to uniquely identify fragmented datagram. */
struct ip_frag_key {
	uint64_t src_dst[4];      /**< src address, first 8 bytes used for IPv4 */
	uint32_t id;           /**< dst address */
	uint32_t key_len;      /**< src/dst key length */
};

/**
 * @internal Fragmented packet to reassemble.
 * First two entries in the frags[] array are for the last and first fragments.
 */
struct ip_frag_pkt {
	TAILQ_ENTRY(ip_frag_pkt) lru;   /**< LRU list */
	struct ip_frag_key key;           /**< fragmentation key */
	uint64_t             start;       /**< creation timestamp */
	uint32_t             total_size;  /**< expected reassembled size */
	uint32_t             frag_size;   /**< size of fragments received */
	uint32_t             last_idx;    /**< index of next entry to fill */
	struct ip_frag       frags[IP_MAX_FRAG_NUM]; /**< fragments */
} __rte_cache_aligned;

#define IP_FRAG_DEATH_ROW_LEN 32 /**< death row size (in packets) */

/** mbuf death row (packets to be freed) */
struct rte_ip_frag_death_row {
	uint32_t cnt;          /**< number of mbufs currently on death row */
	struct rte_mbuf *row[IP_FRAG_DEATH_ROW_LEN * (IP_MAX_FRAG_NUM + 1)];
	/**< mbufs to be freed */
};

TAILQ_HEAD(ip_pkt_list, ip_frag_pkt); /**< @internal fragments tailq */

/** fragmentation table statistics */
struct ip_frag_tbl_stat {
	uint64_t find_num;      /**< total # of find/insert attempts. */
	uint64_t add_num;       /**< # of add ops. */
	uint64_t del_num;       /**< # of del ops. */
	uint64_t reuse_num;     /**< # of reuse (del/add) ops. */
	uint64_t fail_total;    /**< total # of add failures. */
	uint64_t fail_nospace;  /**< # of 'no space' add failures. */
} __rte_cache_aligned;

/** fragmentation table */
struct rte_ip_frag_tbl {
	uint64_t             max_cycles;      /**< ttl for table entries. */
	uint32_t             entry_mask;      /**< hash value mask. */
	uint32_t             max_entries;     /**< max entries allowed. */
	uint32_t             use_entries;     /**< entries in use. */
	uint32_t             bucket_entries;  /**< hash associativity. */
	uint32_t             nb_entries;      /**< total size of the table. */
	uint32_t             nb_buckets;      /**< num of associativity lines. */
	struct ip_frag_pkt *last;         /**< last used entry. */
	struct ip_pkt_list lru;           /**< LRU list for table entries. */
	struct ip_frag_tbl_stat stat;     /**< statistics counters. */
	__extension__ struct ip_frag_pkt pkt[0]; /**< hash table. */
};

/** IPv6 fragment extension header */
#define	RTE_IPV6_EHDR_MF_SHIFT			0
#define	RTE_IPV6_EHDR_MF_MASK			1
#define	RTE_IPV6_EHDR_FO_SHIFT			3
#define	RTE_IPV6_EHDR_FO_MASK			(~((1 << RTE_IPV6_EHDR_FO_SHIFT) - 1))

#define RTE_IPV6_FRAG_USED_MASK			\
	(RTE_IPV6_EHDR_MF_MASK | RTE_IPV6_EHDR_FO_MASK)

#define RTE_IPV6_GET_MF(x)				((x) & RTE_IPV6_EHDR_MF_MASK)
#define RTE_IPV6_GET_FO(x)				((x) >> RTE_IPV6_EHDR_FO_SHIFT)

#define RTE_IPV6_SET_FRAG_DATA(fo, mf)	\
	(((fo) & RTE_IPV6_EHDR_FO_MASK) | ((mf) & RTE_IPV6_EHDR_MF_MASK))

struct ipv6_extension_fragment {
	uint8_t next_header;            /**< Next header type */
	uint8_t reserved;               /**< Reserved */
	uint16_t frag_data;             /**< All fragmentation data */
	uint32_t id;                    /**< Packet ID */
} __attribute__((__packed__));



/**
 * Create a new IP fragmentation table.
 *
 * @param bucket_num
 *   Number of buckets in the hash table.
 * @param bucket_entries
 *   Number of entries per bucket (e.g. hash associativity).
 *   Should be power of two.
 * @param max_entries
 *   Maximum number of entries that could be stored in the table.
 *   The value should be less or equal then bucket_num * bucket_entries.
 * @param max_cycles
 *   Maximum TTL in cycles for each fragmented packet.
 * @param socket_id
 *   The *socket_id* argument is the socket identifier in the case of
 *   NUMA. The value can be *SOCKET_ID_ANY* if there is no NUMA constraints.
 * @return
 *   The pointer to the new allocated fragmentation table, on success. NULL on error.
 */
struct rte_ip_frag_tbl * rte_ip_frag_table_create(uint32_t bucket_num,
		uint32_t bucket_entries,  uint32_t max_entries,
		uint64_t max_cycles, int socket_id);

/**
 * Free allocated IP fragmentation table.
 *
 * @param tbl
 *   Fragmentation table to free.
 */
void
rte_ip_frag_table_destroy(struct rte_ip_frag_tbl *tbl);

/**
 * This function implements the fragmentation of IPv6 packets.
 *
 * @param pkt_in
 *   The input packet.
 * @param pkts_out
 *   Array storing the output fragments.
 * @param nb_pkts_out
 *   Number of fragments.
 * @param mtu_size
 *   Size in bytes of the Maximum Transfer Unit (MTU) for the outgoing IPv6
 *   datagrams. This value includes the size of the IPv6 header.
 * @param pool_direct
 *   MBUF pool used for allocating direct buffers for the output fragments.
 * @param pool_indirect
 *   MBUF pool used for allocating indirect buffers for the output fragments.
 * @return
 *   Upon successful completion - number of output fragments placed
 *   in the pkts_out array.
 *   Otherwise - (-1) * errno.
 */
int32_t
rte_ipv6_fragment_packet(struct rte_mbuf *pkt_in,
		struct rte_mbuf **pkts_out,
		uint16_t nb_pkts_out,
		uint16_t mtu_size,
		struct rte_mempool *pool_direct,
		struct rte_mempool *pool_indirect);

/**
 * This function implements reassembly of fragmented IPv6 packets.
 * Incoming mbuf should have its l2_len/l3_len fields setup correctly.
 *
 * @param tbl
 *   Table where to lookup/add the fragmented packet.
 * @param dr
 *   Death row to free buffers to
 * @param mb
 *   Incoming mbuf with IPv6 fragment.
 * @param tms
 *   Fragment arrival timestamp.
 * @param ip_hdr
 *   Pointer to the IPv6 header.
 * @param frag_hdr
 *   Pointer to the IPv6 fragment extension header.
 * @return
 *   Pointer to mbuf for reassembled packet, or NULL if:
 *   - an error occurred.
 *   - not all fragments of the packet are collected yet.
 */
struct rte_mbuf *rte_ipv6_frag_reassemble_packet(struct rte_ip_frag_tbl *tbl,
		struct rte_ip_frag_death_row *dr,
		struct rte_mbuf *mb, uint64_t tms, struct ipv6_hdr *ip_hdr,
		struct ipv6_extension_fragment *frag_hdr);

/**
 * Return a pointer to the packet's fragment header, if found.
 * It only looks at the extension header that's right after the fixed IPv6
 * header, and doesn't follow the whole chain of extension headers.
 *
 * @param hdr
 *   Pointer to the IPv6 header.
 * @return
 *   Pointer to the IPv6 fragment extension header, or NULL if it's not
 *   present.
 */
static inline struct ipv6_extension_fragment *
rte_ipv6_frag_get_ipv6_fragment_header(struct ipv6_hdr *hdr)
{
	if (hdr->proto == IPPROTO_FRAGMENT) {
		return (struct ipv6_extension_fragment *) ++hdr;
	}
	else
		return NULL;
}

/**
 * IPv4 fragmentation.
 *
 * This function implements the fragmentation of IPv4 packets.
 *
 * @param pkt_in
 *   The input packet.
 * @param pkts_out
 *   Array storing the output fragments.
 * @param nb_pkts_out
 *   Number of fragments.
 * @param mtu_size
 *   Size in bytes of the Maximum Transfer Unit (MTU) for the outgoing IPv4
 *   datagrams. This value includes the size of the IPv4 header.
 * @param pool_direct
 *   MBUF pool used for allocating direct buffers for the output fragments.
 * @param pool_indirect
 *   MBUF pool used for allocating indirect buffers for the output fragments.
 * @return
 *   Upon successful completion - number of output fragments placed
 *   in the pkts_out array.
 *   Otherwise - (-1) * errno.
 */
int32_t rte_ipv4_fragment_packet(struct rte_mbuf *pkt_in,
			struct rte_mbuf **pkts_out,
			uint16_t nb_pkts_out, uint16_t mtu_size,
			struct rte_mempool *pool_direct,
			struct rte_mempool *pool_indirect);

/**
 * This function implements reassembly of fragmented IPv4 packets.
 * Incoming mbufs should have its l2_len/l3_len fields setup correclty.
 *
 * @param tbl
 *   Table where to lookup/add the fragmented packet.
 * @param dr
 *   Death row to free buffers to
 * @param mb
 *   Incoming mbuf with IPv4 fragment.
 * @param tms
 *   Fragment arrival timestamp.
 * @param ip_hdr
 *   Pointer to the IPV4 header inside the fragment.
 * @return
 *   Pointer to mbuf for reassembled packet, or NULL if:
 *   - an error occurred.
 *   - not all fragments of the packet are collected yet.
 */
struct rte_mbuf * rte_ipv4_frag_reassemble_packet(struct rte_ip_frag_tbl *tbl,
		struct rte_ip_frag_death_row *dr,
		struct rte_mbuf *mb, uint64_t tms, struct ipv4_hdr *ip_hdr);

/**
 * Check if the IPv4 packet is fragmented
 *
 * @param hdr
 *   IPv4 header of the packet
 * @return
 *   1 if fragmented, 0 if not fragmented
 */
static inline int
rte_ipv4_frag_pkt_is_fragmented(const struct ipv4_hdr * hdr) {
	uint16_t flag_offset, ip_flag, ip_ofs;

	flag_offset = rte_be_to_cpu_16(hdr->fragment_offset);
	ip_ofs = (uint16_t)(flag_offset & IPV4_HDR_OFFSET_MASK);
	ip_flag = (uint16_t)(flag_offset & IPV4_HDR_MF_FLAG);

	return ip_flag != 0 || ip_ofs  != 0;
}

/**
 * Free mbufs on a given death row.
 *
 * @param dr
 *   Death row to free mbufs in.
 * @param prefetch
 *   How many buffers to prefetch before freeing.
 */
void rte_ip_frag_free_death_row(struct rte_ip_frag_death_row *dr,
		uint32_t prefetch);


/**
 * Dump fragmentation table statistics to file.
 *
 * @param f
 *   File to dump statistics to
 * @param tbl
 *   Fragmentation table to dump statistics from
 */
void
rte_ip_frag_table_statistics_dump(FILE * f, const struct rte_ip_frag_tbl *tbl);

#ifdef __cplusplus
}
#endif

#endif /* _RTE_IP_FRAG_H_ */