1 // SPDX-License-Identifier: GPL-2.0
2 /* Copyright(c) 2017 Oracle and/or its affiliates. All rights reserved. */
3 
4 #include "ixgbe.h"
5 #include <net/xfrm.h>
6 #include <crypto/aead.h>
7 #include <linux/if_bridge.h>
8 
9 #define IXGBE_IPSEC_KEY_BITS  160
10 static const char aes_gcm_name[] = "rfc4106(gcm(aes))";
11 
12 static void ixgbe_ipsec_del_sa(struct xfrm_state *xs);
13 
14 /**
15  * ixgbe_ipsec_set_tx_sa - set the Tx SA registers
16  * @hw: hw specific details
17  * @idx: register index to write
18  * @key: key byte array
19  * @salt: salt bytes
20  **/
21 static void ixgbe_ipsec_set_tx_sa(struct ixgbe_hw *hw, u16 idx,
22 				  u32 key[], u32 salt)
23 {
24 	u32 reg;
25 	int i;
26 
27 	for (i = 0; i < 4; i++)
28 		IXGBE_WRITE_REG(hw, IXGBE_IPSTXKEY(i),
29 				(__force u32)cpu_to_be32(key[3 - i]));
30 	IXGBE_WRITE_REG(hw, IXGBE_IPSTXSALT, (__force u32)cpu_to_be32(salt));
31 	IXGBE_WRITE_FLUSH(hw);
32 
33 	reg = IXGBE_READ_REG(hw, IXGBE_IPSTXIDX);
34 	reg &= IXGBE_RXTXIDX_IPS_EN;
35 	reg |= idx << IXGBE_RXTXIDX_IDX_SHIFT | IXGBE_RXTXIDX_WRITE;
36 	IXGBE_WRITE_REG(hw, IXGBE_IPSTXIDX, reg);
37 	IXGBE_WRITE_FLUSH(hw);
38 }
39 
40 /**
41  * ixgbe_ipsec_set_rx_item - set an Rx table item
42  * @hw: hw specific details
43  * @idx: register index to write
44  * @tbl: table selector
45  *
46  * Trigger the device to store into a particular Rx table the
47  * data that has already been loaded into the input register
48  **/
49 static void ixgbe_ipsec_set_rx_item(struct ixgbe_hw *hw, u16 idx,
50 				    enum ixgbe_ipsec_tbl_sel tbl)
51 {
52 	u32 reg;
53 
54 	reg = IXGBE_READ_REG(hw, IXGBE_IPSRXIDX);
55 	reg &= IXGBE_RXTXIDX_IPS_EN;
56 	reg |= tbl << IXGBE_RXIDX_TBL_SHIFT |
57 	       idx << IXGBE_RXTXIDX_IDX_SHIFT |
58 	       IXGBE_RXTXIDX_WRITE;
59 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXIDX, reg);
60 	IXGBE_WRITE_FLUSH(hw);
61 }
62 
63 /**
64  * ixgbe_ipsec_set_rx_sa - set up the register bits to save SA info
65  * @hw: hw specific details
66  * @idx: register index to write
67  * @spi: security parameter index
68  * @key: key byte array
69  * @salt: salt bytes
70  * @mode: rx decrypt control bits
71  * @ip_idx: index into IP table for related IP address
72  **/
73 static void ixgbe_ipsec_set_rx_sa(struct ixgbe_hw *hw, u16 idx, __be32 spi,
74 				  u32 key[], u32 salt, u32 mode, u32 ip_idx)
75 {
76 	int i;
77 
78 	/* store the SPI (in bigendian) and IPidx */
79 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXSPI,
80 			(__force u32)cpu_to_le32((__force u32)spi));
81 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXIPIDX, ip_idx);
82 	IXGBE_WRITE_FLUSH(hw);
83 
84 	ixgbe_ipsec_set_rx_item(hw, idx, ips_rx_spi_tbl);
85 
86 	/* store the key, salt, and mode */
87 	for (i = 0; i < 4; i++)
88 		IXGBE_WRITE_REG(hw, IXGBE_IPSRXKEY(i),
89 				(__force u32)cpu_to_be32(key[3 - i]));
90 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXSALT, (__force u32)cpu_to_be32(salt));
91 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXMOD, mode);
92 	IXGBE_WRITE_FLUSH(hw);
93 
94 	ixgbe_ipsec_set_rx_item(hw, idx, ips_rx_key_tbl);
95 }
96 
97 /**
98  * ixgbe_ipsec_set_rx_ip - set up the register bits to save SA IP addr info
99  * @hw: hw specific details
100  * @idx: register index to write
101  * @addr: IP address byte array
102  **/
103 static void ixgbe_ipsec_set_rx_ip(struct ixgbe_hw *hw, u16 idx, __be32 addr[])
104 {
105 	int i;
106 
107 	/* store the ip address */
108 	for (i = 0; i < 4; i++)
109 		IXGBE_WRITE_REG(hw, IXGBE_IPSRXIPADDR(i),
110 				(__force u32)cpu_to_le32((__force u32)addr[i]));
111 	IXGBE_WRITE_FLUSH(hw);
112 
113 	ixgbe_ipsec_set_rx_item(hw, idx, ips_rx_ip_tbl);
114 }
115 
116 /**
117  * ixgbe_ipsec_clear_hw_tables - because some tables don't get cleared on reset
118  * @adapter: board private structure
119  **/
120 static void ixgbe_ipsec_clear_hw_tables(struct ixgbe_adapter *adapter)
121 {
122 	struct ixgbe_hw *hw = &adapter->hw;
123 	u32 buf[4] = {0, 0, 0, 0};
124 	u16 idx;
125 
126 	/* disable Rx and Tx SA lookup */
127 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXIDX, 0);
128 	IXGBE_WRITE_REG(hw, IXGBE_IPSTXIDX, 0);
129 
130 	/* scrub the tables - split the loops for the max of the IP table */
131 	for (idx = 0; idx < IXGBE_IPSEC_MAX_RX_IP_COUNT; idx++) {
132 		ixgbe_ipsec_set_tx_sa(hw, idx, buf, 0);
133 		ixgbe_ipsec_set_rx_sa(hw, idx, 0, buf, 0, 0, 0);
134 		ixgbe_ipsec_set_rx_ip(hw, idx, (__be32 *)buf);
135 	}
136 	for (; idx < IXGBE_IPSEC_MAX_SA_COUNT; idx++) {
137 		ixgbe_ipsec_set_tx_sa(hw, idx, buf, 0);
138 		ixgbe_ipsec_set_rx_sa(hw, idx, 0, buf, 0, 0, 0);
139 	}
140 }
141 
142 /**
143  * ixgbe_ipsec_stop_data
144  * @adapter: board private structure
145  **/
146 static void ixgbe_ipsec_stop_data(struct ixgbe_adapter *adapter)
147 {
148 	struct ixgbe_hw *hw = &adapter->hw;
149 	bool link = adapter->link_up;
150 	u32 t_rdy, r_rdy;
151 	u32 limit;
152 	u32 reg;
153 
154 	/* halt data paths */
155 	reg = IXGBE_READ_REG(hw, IXGBE_SECTXCTRL);
156 	reg |= IXGBE_SECTXCTRL_TX_DIS;
157 	IXGBE_WRITE_REG(hw, IXGBE_SECTXCTRL, reg);
158 
159 	reg = IXGBE_READ_REG(hw, IXGBE_SECRXCTRL);
160 	reg |= IXGBE_SECRXCTRL_RX_DIS;
161 	IXGBE_WRITE_REG(hw, IXGBE_SECRXCTRL, reg);
162 
163 	/* If both Tx and Rx are ready there are no packets
164 	 * that we need to flush so the loopback configuration
165 	 * below is not necessary.
166 	 */
167 	t_rdy = IXGBE_READ_REG(hw, IXGBE_SECTXSTAT) &
168 		IXGBE_SECTXSTAT_SECTX_RDY;
169 	r_rdy = IXGBE_READ_REG(hw, IXGBE_SECRXSTAT) &
170 		IXGBE_SECRXSTAT_SECRX_RDY;
171 	if (t_rdy && r_rdy)
172 		return;
173 
174 	/* If the tx fifo doesn't have link, but still has data,
175 	 * we can't clear the tx sec block.  Set the MAC loopback
176 	 * before block clear
177 	 */
178 	if (!link) {
179 		reg = IXGBE_READ_REG(hw, IXGBE_MACC);
180 		reg |= IXGBE_MACC_FLU;
181 		IXGBE_WRITE_REG(hw, IXGBE_MACC, reg);
182 
183 		reg = IXGBE_READ_REG(hw, IXGBE_HLREG0);
184 		reg |= IXGBE_HLREG0_LPBK;
185 		IXGBE_WRITE_REG(hw, IXGBE_HLREG0, reg);
186 
187 		IXGBE_WRITE_FLUSH(hw);
188 		mdelay(3);
189 	}
190 
191 	/* wait for the paths to empty */
192 	limit = 20;
193 	do {
194 		mdelay(10);
195 		t_rdy = IXGBE_READ_REG(hw, IXGBE_SECTXSTAT) &
196 			IXGBE_SECTXSTAT_SECTX_RDY;
197 		r_rdy = IXGBE_READ_REG(hw, IXGBE_SECRXSTAT) &
198 			IXGBE_SECRXSTAT_SECRX_RDY;
199 	} while (!(t_rdy && r_rdy) && limit--);
200 
201 	/* undo loopback if we played with it earlier */
202 	if (!link) {
203 		reg = IXGBE_READ_REG(hw, IXGBE_MACC);
204 		reg &= ~IXGBE_MACC_FLU;
205 		IXGBE_WRITE_REG(hw, IXGBE_MACC, reg);
206 
207 		reg = IXGBE_READ_REG(hw, IXGBE_HLREG0);
208 		reg &= ~IXGBE_HLREG0_LPBK;
209 		IXGBE_WRITE_REG(hw, IXGBE_HLREG0, reg);
210 
211 		IXGBE_WRITE_FLUSH(hw);
212 	}
213 }
214 
215 /**
216  * ixgbe_ipsec_stop_engine
217  * @adapter: board private structure
218  **/
219 static void ixgbe_ipsec_stop_engine(struct ixgbe_adapter *adapter)
220 {
221 	struct ixgbe_hw *hw = &adapter->hw;
222 	u32 reg;
223 
224 	ixgbe_ipsec_stop_data(adapter);
225 
226 	/* disable Rx and Tx SA lookup */
227 	IXGBE_WRITE_REG(hw, IXGBE_IPSTXIDX, 0);
228 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXIDX, 0);
229 
230 	/* disable the Rx and Tx engines and full packet store-n-forward */
231 	reg = IXGBE_READ_REG(hw, IXGBE_SECTXCTRL);
232 	reg |= IXGBE_SECTXCTRL_SECTX_DIS;
233 	reg &= ~IXGBE_SECTXCTRL_STORE_FORWARD;
234 	IXGBE_WRITE_REG(hw, IXGBE_SECTXCTRL, reg);
235 
236 	reg = IXGBE_READ_REG(hw, IXGBE_SECRXCTRL);
237 	reg |= IXGBE_SECRXCTRL_SECRX_DIS;
238 	IXGBE_WRITE_REG(hw, IXGBE_SECRXCTRL, reg);
239 
240 	/* restore the "tx security buffer almost full threshold" to 0x250 */
241 	IXGBE_WRITE_REG(hw, IXGBE_SECTXBUFFAF, 0x250);
242 
243 	/* Set minimum IFG between packets back to the default 0x1 */
244 	reg = IXGBE_READ_REG(hw, IXGBE_SECTXMINIFG);
245 	reg = (reg & 0xfffffff0) | 0x1;
246 	IXGBE_WRITE_REG(hw, IXGBE_SECTXMINIFG, reg);
247 
248 	/* final set for normal (no ipsec offload) processing */
249 	IXGBE_WRITE_REG(hw, IXGBE_SECTXCTRL, IXGBE_SECTXCTRL_SECTX_DIS);
250 	IXGBE_WRITE_REG(hw, IXGBE_SECRXCTRL, IXGBE_SECRXCTRL_SECRX_DIS);
251 
252 	IXGBE_WRITE_FLUSH(hw);
253 }
254 
255 /**
256  * ixgbe_ipsec_start_engine
257  * @adapter: board private structure
258  *
259  * NOTE: this increases power consumption whether being used or not
260  **/
261 static void ixgbe_ipsec_start_engine(struct ixgbe_adapter *adapter)
262 {
263 	struct ixgbe_hw *hw = &adapter->hw;
264 	u32 reg;
265 
266 	ixgbe_ipsec_stop_data(adapter);
267 
268 	/* Set minimum IFG between packets to 3 */
269 	reg = IXGBE_READ_REG(hw, IXGBE_SECTXMINIFG);
270 	reg = (reg & 0xfffffff0) | 0x3;
271 	IXGBE_WRITE_REG(hw, IXGBE_SECTXMINIFG, reg);
272 
273 	/* Set "tx security buffer almost full threshold" to 0x15 so that the
274 	 * almost full indication is generated only after buffer contains at
275 	 * least an entire jumbo packet.
276 	 */
277 	reg = IXGBE_READ_REG(hw, IXGBE_SECTXBUFFAF);
278 	reg = (reg & 0xfffffc00) | 0x15;
279 	IXGBE_WRITE_REG(hw, IXGBE_SECTXBUFFAF, reg);
280 
281 	/* restart the data paths by clearing the DISABLE bits */
282 	IXGBE_WRITE_REG(hw, IXGBE_SECRXCTRL, 0);
283 	IXGBE_WRITE_REG(hw, IXGBE_SECTXCTRL, IXGBE_SECTXCTRL_STORE_FORWARD);
284 
285 	/* enable Rx and Tx SA lookup */
286 	IXGBE_WRITE_REG(hw, IXGBE_IPSTXIDX, IXGBE_RXTXIDX_IPS_EN);
287 	IXGBE_WRITE_REG(hw, IXGBE_IPSRXIDX, IXGBE_RXTXIDX_IPS_EN);
288 
289 	IXGBE_WRITE_FLUSH(hw);
290 }
291 
292 /**
293  * ixgbe_ipsec_restore - restore the ipsec HW settings after a reset
294  * @adapter: board private structure
295  *
296  * Reload the HW tables from the SW tables after they've been bashed
297  * by a chip reset.
298  *
299  * Any VF entries are removed from the SW and HW tables since either
300  * (a) the VF also gets reset on PF reset and will ask again for the
301  * offloads, or (b) the VF has been removed by a change in the num_vfs.
302  **/
303 void ixgbe_ipsec_restore(struct ixgbe_adapter *adapter)
304 {
305 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
306 	struct ixgbe_hw *hw = &adapter->hw;
307 	int i;
308 
309 	if (!(adapter->flags2 & IXGBE_FLAG2_IPSEC_ENABLED))
310 		return;
311 
312 	/* clean up and restart the engine */
313 	ixgbe_ipsec_stop_engine(adapter);
314 	ixgbe_ipsec_clear_hw_tables(adapter);
315 	ixgbe_ipsec_start_engine(adapter);
316 
317 	/* reload the Rx and Tx keys */
318 	for (i = 0; i < IXGBE_IPSEC_MAX_SA_COUNT; i++) {
319 		struct rx_sa *r = &ipsec->rx_tbl[i];
320 		struct tx_sa *t = &ipsec->tx_tbl[i];
321 
322 		if (r->used) {
323 			if (r->mode & IXGBE_RXTXMOD_VF)
324 				ixgbe_ipsec_del_sa(r->xs);
325 			else
326 				ixgbe_ipsec_set_rx_sa(hw, i, r->xs->id.spi,
327 						      r->key, r->salt,
328 						      r->mode, r->iptbl_ind);
329 		}
330 
331 		if (t->used) {
332 			if (t->mode & IXGBE_RXTXMOD_VF)
333 				ixgbe_ipsec_del_sa(t->xs);
334 			else
335 				ixgbe_ipsec_set_tx_sa(hw, i, t->key, t->salt);
336 		}
337 	}
338 
339 	/* reload the IP addrs */
340 	for (i = 0; i < IXGBE_IPSEC_MAX_RX_IP_COUNT; i++) {
341 		struct rx_ip_sa *ipsa = &ipsec->ip_tbl[i];
342 
343 		if (ipsa->used)
344 			ixgbe_ipsec_set_rx_ip(hw, i, ipsa->ipaddr);
345 	}
346 }
347 
348 /**
349  * ixgbe_ipsec_find_empty_idx - find the first unused security parameter index
350  * @ipsec: pointer to ipsec struct
351  * @rxtable: true if we need to look in the Rx table
352  *
353  * Returns the first unused index in either the Rx or Tx SA table
354  **/
355 static int ixgbe_ipsec_find_empty_idx(struct ixgbe_ipsec *ipsec, bool rxtable)
356 {
357 	u32 i;
358 
359 	if (rxtable) {
360 		if (ipsec->num_rx_sa == IXGBE_IPSEC_MAX_SA_COUNT)
361 			return -ENOSPC;
362 
363 		/* search rx sa table */
364 		for (i = 0; i < IXGBE_IPSEC_MAX_SA_COUNT; i++) {
365 			if (!ipsec->rx_tbl[i].used)
366 				return i;
367 		}
368 	} else {
369 		if (ipsec->num_tx_sa == IXGBE_IPSEC_MAX_SA_COUNT)
370 			return -ENOSPC;
371 
372 		/* search tx sa table */
373 		for (i = 0; i < IXGBE_IPSEC_MAX_SA_COUNT; i++) {
374 			if (!ipsec->tx_tbl[i].used)
375 				return i;
376 		}
377 	}
378 
379 	return -ENOSPC;
380 }
381 
382 /**
383  * ixgbe_ipsec_find_rx_state - find the state that matches
384  * @ipsec: pointer to ipsec struct
385  * @daddr: inbound address to match
386  * @proto: protocol to match
387  * @spi: SPI to match
388  * @ip4: true if using an ipv4 address
389  *
390  * Returns a pointer to the matching SA state information
391  **/
392 static struct xfrm_state *ixgbe_ipsec_find_rx_state(struct ixgbe_ipsec *ipsec,
393 						    __be32 *daddr, u8 proto,
394 						    __be32 spi, bool ip4)
395 {
396 	struct rx_sa *rsa;
397 	struct xfrm_state *ret = NULL;
398 
399 	rcu_read_lock();
400 	hash_for_each_possible_rcu(ipsec->rx_sa_list, rsa, hlist,
401 				   (__force u32)spi) {
402 		if (rsa->mode & IXGBE_RXTXMOD_VF)
403 			continue;
404 		if (spi == rsa->xs->id.spi &&
405 		    ((ip4 && *daddr == rsa->xs->id.daddr.a4) ||
406 		      (!ip4 && !memcmp(daddr, &rsa->xs->id.daddr.a6,
407 				       sizeof(rsa->xs->id.daddr.a6)))) &&
408 		    proto == rsa->xs->id.proto) {
409 			ret = rsa->xs;
410 			xfrm_state_hold(ret);
411 			break;
412 		}
413 	}
414 	rcu_read_unlock();
415 	return ret;
416 }
417 
418 /**
419  * ixgbe_ipsec_parse_proto_keys - find the key and salt based on the protocol
420  * @xs: pointer to xfrm_state struct
421  * @mykey: pointer to key array to populate
422  * @mysalt: pointer to salt value to populate
423  *
424  * This copies the protocol keys and salt to our own data tables.  The
425  * 82599 family only supports the one algorithm.
426  **/
427 static int ixgbe_ipsec_parse_proto_keys(struct xfrm_state *xs,
428 					u32 *mykey, u32 *mysalt)
429 {
430 	struct net_device *dev = xs->xso.real_dev;
431 	unsigned char *key_data;
432 	char *alg_name = NULL;
433 	int key_len;
434 
435 	if (!xs->aead) {
436 		netdev_err(dev, "Unsupported IPsec algorithm\n");
437 		return -EINVAL;
438 	}
439 
440 	if (xs->aead->alg_icv_len != IXGBE_IPSEC_AUTH_BITS) {
441 		netdev_err(dev, "IPsec offload requires %d bit authentication\n",
442 			   IXGBE_IPSEC_AUTH_BITS);
443 		return -EINVAL;
444 	}
445 
446 	key_data = &xs->aead->alg_key[0];
447 	key_len = xs->aead->alg_key_len;
448 	alg_name = xs->aead->alg_name;
449 
450 	if (strcmp(alg_name, aes_gcm_name)) {
451 		netdev_err(dev, "Unsupported IPsec algorithm - please use %s\n",
452 			   aes_gcm_name);
453 		return -EINVAL;
454 	}
455 
456 	/* The key bytes come down in a bigendian array of bytes, so
457 	 * we don't need to do any byteswapping.
458 	 * 160 accounts for 16 byte key and 4 byte salt
459 	 */
460 	if (key_len == IXGBE_IPSEC_KEY_BITS) {
461 		*mysalt = ((u32 *)key_data)[4];
462 	} else if (key_len != (IXGBE_IPSEC_KEY_BITS - (sizeof(*mysalt) * 8))) {
463 		netdev_err(dev, "IPsec hw offload only supports keys up to 128 bits with a 32 bit salt\n");
464 		return -EINVAL;
465 	} else {
466 		netdev_info(dev, "IPsec hw offload parameters missing 32 bit salt value\n");
467 		*mysalt = 0;
468 	}
469 	memcpy(mykey, key_data, 16);
470 
471 	return 0;
472 }
473 
474 /**
475  * ixgbe_ipsec_check_mgmt_ip - make sure there is no clash with mgmt IP filters
476  * @xs: pointer to transformer state struct
477  **/
478 static int ixgbe_ipsec_check_mgmt_ip(struct xfrm_state *xs)
479 {
480 	struct net_device *dev = xs->xso.real_dev;
481 	struct ixgbe_adapter *adapter = netdev_priv(dev);
482 	struct ixgbe_hw *hw = &adapter->hw;
483 	u32 mfval, manc, reg;
484 	int num_filters = 4;
485 	bool manc_ipv4;
486 	u32 bmcipval;
487 	int i, j;
488 
489 #define MANC_EN_IPV4_FILTER      BIT(24)
490 #define MFVAL_IPV4_FILTER_SHIFT  16
491 #define MFVAL_IPV6_FILTER_SHIFT  24
492 #define MIPAF_ARR(_m, _n)        (IXGBE_MIPAF + ((_m) * 0x10) + ((_n) * 4))
493 
494 #define IXGBE_BMCIP(_n)          (0x5050 + ((_n) * 4))
495 #define IXGBE_BMCIPVAL           0x5060
496 #define BMCIP_V4                 0x2
497 #define BMCIP_V6                 0x3
498 #define BMCIP_MASK               0x3
499 
500 	manc = IXGBE_READ_REG(hw, IXGBE_MANC);
501 	manc_ipv4 = !!(manc & MANC_EN_IPV4_FILTER);
502 	mfval = IXGBE_READ_REG(hw, IXGBE_MFVAL);
503 	bmcipval = IXGBE_READ_REG(hw, IXGBE_BMCIPVAL);
504 
505 	if (xs->props.family == AF_INET) {
506 		/* are there any IPv4 filters to check? */
507 		if (manc_ipv4) {
508 			/* the 4 ipv4 filters are all in MIPAF(3, i) */
509 			for (i = 0; i < num_filters; i++) {
510 				if (!(mfval & BIT(MFVAL_IPV4_FILTER_SHIFT + i)))
511 					continue;
512 
513 				reg = IXGBE_READ_REG(hw, MIPAF_ARR(3, i));
514 				if (reg == xs->id.daddr.a4)
515 					return 1;
516 			}
517 		}
518 
519 		if ((bmcipval & BMCIP_MASK) == BMCIP_V4) {
520 			reg = IXGBE_READ_REG(hw, IXGBE_BMCIP(3));
521 			if (reg == xs->id.daddr.a4)
522 				return 1;
523 		}
524 
525 	} else {
526 		/* if there are ipv4 filters, they are in the last ipv6 slot */
527 		if (manc_ipv4)
528 			num_filters = 3;
529 
530 		for (i = 0; i < num_filters; i++) {
531 			if (!(mfval & BIT(MFVAL_IPV6_FILTER_SHIFT + i)))
532 				continue;
533 
534 			for (j = 0; j < 4; j++) {
535 				reg = IXGBE_READ_REG(hw, MIPAF_ARR(i, j));
536 				if (reg != xs->id.daddr.a6[j])
537 					break;
538 			}
539 			if (j == 4)   /* did we match all 4 words? */
540 				return 1;
541 		}
542 
543 		if ((bmcipval & BMCIP_MASK) == BMCIP_V6) {
544 			for (j = 0; j < 4; j++) {
545 				reg = IXGBE_READ_REG(hw, IXGBE_BMCIP(j));
546 				if (reg != xs->id.daddr.a6[j])
547 					break;
548 			}
549 			if (j == 4)   /* did we match all 4 words? */
550 				return 1;
551 		}
552 	}
553 
554 	return 0;
555 }
556 
557 /**
558  * ixgbe_ipsec_add_sa - program device with a security association
559  * @xs: pointer to transformer state struct
560  **/
561 static int ixgbe_ipsec_add_sa(struct xfrm_state *xs)
562 {
563 	struct net_device *dev = xs->xso.real_dev;
564 	struct ixgbe_adapter *adapter = netdev_priv(dev);
565 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
566 	struct ixgbe_hw *hw = &adapter->hw;
567 	int checked, match, first;
568 	u16 sa_idx;
569 	int ret;
570 	int i;
571 
572 	if (xs->id.proto != IPPROTO_ESP && xs->id.proto != IPPROTO_AH) {
573 		netdev_err(dev, "Unsupported protocol 0x%04x for ipsec offload\n",
574 			   xs->id.proto);
575 		return -EINVAL;
576 	}
577 
578 	if (ixgbe_ipsec_check_mgmt_ip(xs)) {
579 		netdev_err(dev, "IPsec IP addr clash with mgmt filters\n");
580 		return -EINVAL;
581 	}
582 
583 	if (xs->xso.flags & XFRM_OFFLOAD_INBOUND) {
584 		struct rx_sa rsa;
585 
586 		if (xs->calg) {
587 			netdev_err(dev, "Compression offload not supported\n");
588 			return -EINVAL;
589 		}
590 
591 		/* find the first unused index */
592 		ret = ixgbe_ipsec_find_empty_idx(ipsec, true);
593 		if (ret < 0) {
594 			netdev_err(dev, "No space for SA in Rx table!\n");
595 			return ret;
596 		}
597 		sa_idx = (u16)ret;
598 
599 		memset(&rsa, 0, sizeof(rsa));
600 		rsa.used = true;
601 		rsa.xs = xs;
602 
603 		if (rsa.xs->id.proto & IPPROTO_ESP)
604 			rsa.decrypt = xs->ealg || xs->aead;
605 
606 		/* get the key and salt */
607 		ret = ixgbe_ipsec_parse_proto_keys(xs, rsa.key, &rsa.salt);
608 		if (ret) {
609 			netdev_err(dev, "Failed to get key data for Rx SA table\n");
610 			return ret;
611 		}
612 
613 		/* get ip for rx sa table */
614 		if (xs->props.family == AF_INET6)
615 			memcpy(rsa.ipaddr, &xs->id.daddr.a6, 16);
616 		else
617 			memcpy(&rsa.ipaddr[3], &xs->id.daddr.a4, 4);
618 
619 		/* The HW does not have a 1:1 mapping from keys to IP addrs, so
620 		 * check for a matching IP addr entry in the table.  If the addr
621 		 * already exists, use it; else find an unused slot and add the
622 		 * addr.  If one does not exist and there are no unused table
623 		 * entries, fail the request.
624 		 */
625 
626 		/* Find an existing match or first not used, and stop looking
627 		 * after we've checked all we know we have.
628 		 */
629 		checked = 0;
630 		match = -1;
631 		first = -1;
632 		for (i = 0;
633 		     i < IXGBE_IPSEC_MAX_RX_IP_COUNT &&
634 		     (checked < ipsec->num_rx_sa || first < 0);
635 		     i++) {
636 			if (ipsec->ip_tbl[i].used) {
637 				if (!memcmp(ipsec->ip_tbl[i].ipaddr,
638 					    rsa.ipaddr, sizeof(rsa.ipaddr))) {
639 					match = i;
640 					break;
641 				}
642 				checked++;
643 			} else if (first < 0) {
644 				first = i;  /* track the first empty seen */
645 			}
646 		}
647 
648 		if (ipsec->num_rx_sa == 0)
649 			first = 0;
650 
651 		if (match >= 0) {
652 			/* addrs are the same, we should use this one */
653 			rsa.iptbl_ind = match;
654 			ipsec->ip_tbl[match].ref_cnt++;
655 
656 		} else if (first >= 0) {
657 			/* no matches, but here's an empty slot */
658 			rsa.iptbl_ind = first;
659 
660 			memcpy(ipsec->ip_tbl[first].ipaddr,
661 			       rsa.ipaddr, sizeof(rsa.ipaddr));
662 			ipsec->ip_tbl[first].ref_cnt = 1;
663 			ipsec->ip_tbl[first].used = true;
664 
665 			ixgbe_ipsec_set_rx_ip(hw, rsa.iptbl_ind, rsa.ipaddr);
666 
667 		} else {
668 			/* no match and no empty slot */
669 			netdev_err(dev, "No space for SA in Rx IP SA table\n");
670 			memset(&rsa, 0, sizeof(rsa));
671 			return -ENOSPC;
672 		}
673 
674 		rsa.mode = IXGBE_RXMOD_VALID;
675 		if (rsa.xs->id.proto & IPPROTO_ESP)
676 			rsa.mode |= IXGBE_RXMOD_PROTO_ESP;
677 		if (rsa.decrypt)
678 			rsa.mode |= IXGBE_RXMOD_DECRYPT;
679 		if (rsa.xs->props.family == AF_INET6)
680 			rsa.mode |= IXGBE_RXMOD_IPV6;
681 
682 		/* the preparations worked, so save the info */
683 		memcpy(&ipsec->rx_tbl[sa_idx], &rsa, sizeof(rsa));
684 
685 		ixgbe_ipsec_set_rx_sa(hw, sa_idx, rsa.xs->id.spi, rsa.key,
686 				      rsa.salt, rsa.mode, rsa.iptbl_ind);
687 		xs->xso.offload_handle = sa_idx + IXGBE_IPSEC_BASE_RX_INDEX;
688 
689 		ipsec->num_rx_sa++;
690 
691 		/* hash the new entry for faster search in Rx path */
692 		hash_add_rcu(ipsec->rx_sa_list, &ipsec->rx_tbl[sa_idx].hlist,
693 			     (__force u32)rsa.xs->id.spi);
694 	} else {
695 		struct tx_sa tsa;
696 
697 		if (adapter->num_vfs &&
698 		    adapter->bridge_mode != BRIDGE_MODE_VEPA)
699 			return -EOPNOTSUPP;
700 
701 		/* find the first unused index */
702 		ret = ixgbe_ipsec_find_empty_idx(ipsec, false);
703 		if (ret < 0) {
704 			netdev_err(dev, "No space for SA in Tx table\n");
705 			return ret;
706 		}
707 		sa_idx = (u16)ret;
708 
709 		memset(&tsa, 0, sizeof(tsa));
710 		tsa.used = true;
711 		tsa.xs = xs;
712 
713 		if (xs->id.proto & IPPROTO_ESP)
714 			tsa.encrypt = xs->ealg || xs->aead;
715 
716 		ret = ixgbe_ipsec_parse_proto_keys(xs, tsa.key, &tsa.salt);
717 		if (ret) {
718 			netdev_err(dev, "Failed to get key data for Tx SA table\n");
719 			memset(&tsa, 0, sizeof(tsa));
720 			return ret;
721 		}
722 
723 		/* the preparations worked, so save the info */
724 		memcpy(&ipsec->tx_tbl[sa_idx], &tsa, sizeof(tsa));
725 
726 		ixgbe_ipsec_set_tx_sa(hw, sa_idx, tsa.key, tsa.salt);
727 
728 		xs->xso.offload_handle = sa_idx + IXGBE_IPSEC_BASE_TX_INDEX;
729 
730 		ipsec->num_tx_sa++;
731 	}
732 
733 	/* enable the engine if not already warmed up */
734 	if (!(adapter->flags2 & IXGBE_FLAG2_IPSEC_ENABLED)) {
735 		ixgbe_ipsec_start_engine(adapter);
736 		adapter->flags2 |= IXGBE_FLAG2_IPSEC_ENABLED;
737 	}
738 
739 	return 0;
740 }
741 
742 /**
743  * ixgbe_ipsec_del_sa - clear out this specific SA
744  * @xs: pointer to transformer state struct
745  **/
746 static void ixgbe_ipsec_del_sa(struct xfrm_state *xs)
747 {
748 	struct net_device *dev = xs->xso.real_dev;
749 	struct ixgbe_adapter *adapter = netdev_priv(dev);
750 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
751 	struct ixgbe_hw *hw = &adapter->hw;
752 	u32 zerobuf[4] = {0, 0, 0, 0};
753 	u16 sa_idx;
754 
755 	if (xs->xso.flags & XFRM_OFFLOAD_INBOUND) {
756 		struct rx_sa *rsa;
757 		u8 ipi;
758 
759 		sa_idx = xs->xso.offload_handle - IXGBE_IPSEC_BASE_RX_INDEX;
760 		rsa = &ipsec->rx_tbl[sa_idx];
761 
762 		if (!rsa->used) {
763 			netdev_err(dev, "Invalid Rx SA selected sa_idx=%d offload_handle=%lu\n",
764 				   sa_idx, xs->xso.offload_handle);
765 			return;
766 		}
767 
768 		ixgbe_ipsec_set_rx_sa(hw, sa_idx, 0, zerobuf, 0, 0, 0);
769 		hash_del_rcu(&rsa->hlist);
770 
771 		/* if the IP table entry is referenced by only this SA,
772 		 * i.e. ref_cnt is only 1, clear the IP table entry as well
773 		 */
774 		ipi = rsa->iptbl_ind;
775 		if (ipsec->ip_tbl[ipi].ref_cnt > 0) {
776 			ipsec->ip_tbl[ipi].ref_cnt--;
777 
778 			if (!ipsec->ip_tbl[ipi].ref_cnt) {
779 				memset(&ipsec->ip_tbl[ipi], 0,
780 				       sizeof(struct rx_ip_sa));
781 				ixgbe_ipsec_set_rx_ip(hw, ipi,
782 						      (__force __be32 *)zerobuf);
783 			}
784 		}
785 
786 		memset(rsa, 0, sizeof(struct rx_sa));
787 		ipsec->num_rx_sa--;
788 	} else {
789 		sa_idx = xs->xso.offload_handle - IXGBE_IPSEC_BASE_TX_INDEX;
790 
791 		if (!ipsec->tx_tbl[sa_idx].used) {
792 			netdev_err(dev, "Invalid Tx SA selected sa_idx=%d offload_handle=%lu\n",
793 				   sa_idx, xs->xso.offload_handle);
794 			return;
795 		}
796 
797 		ixgbe_ipsec_set_tx_sa(hw, sa_idx, zerobuf, 0);
798 		memset(&ipsec->tx_tbl[sa_idx], 0, sizeof(struct tx_sa));
799 		ipsec->num_tx_sa--;
800 	}
801 
802 	/* if there are no SAs left, stop the engine to save energy */
803 	if (ipsec->num_rx_sa == 0 && ipsec->num_tx_sa == 0) {
804 		adapter->flags2 &= ~IXGBE_FLAG2_IPSEC_ENABLED;
805 		ixgbe_ipsec_stop_engine(adapter);
806 	}
807 }
808 
809 /**
810  * ixgbe_ipsec_offload_ok - can this packet use the xfrm hw offload
811  * @skb: current data packet
812  * @xs: pointer to transformer state struct
813  **/
814 static bool ixgbe_ipsec_offload_ok(struct sk_buff *skb, struct xfrm_state *xs)
815 {
816 	if (xs->props.family == AF_INET) {
817 		/* Offload with IPv4 options is not supported yet */
818 		if (ip_hdr(skb)->ihl != 5)
819 			return false;
820 	} else {
821 		/* Offload with IPv6 extension headers is not support yet */
822 		if (ipv6_ext_hdr(ipv6_hdr(skb)->nexthdr))
823 			return false;
824 	}
825 
826 	return true;
827 }
828 
829 static const struct xfrmdev_ops ixgbe_xfrmdev_ops = {
830 	.xdo_dev_state_add = ixgbe_ipsec_add_sa,
831 	.xdo_dev_state_delete = ixgbe_ipsec_del_sa,
832 	.xdo_dev_offload_ok = ixgbe_ipsec_offload_ok,
833 };
834 
835 /**
836  * ixgbe_ipsec_vf_clear - clear the tables of data for a VF
837  * @adapter: board private structure
838  * @vf: VF id to be removed
839  **/
840 void ixgbe_ipsec_vf_clear(struct ixgbe_adapter *adapter, u32 vf)
841 {
842 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
843 	int i;
844 
845 	if (!ipsec)
846 		return;
847 
848 	/* search rx sa table */
849 	for (i = 0; i < IXGBE_IPSEC_MAX_SA_COUNT && ipsec->num_rx_sa; i++) {
850 		if (!ipsec->rx_tbl[i].used)
851 			continue;
852 		if (ipsec->rx_tbl[i].mode & IXGBE_RXTXMOD_VF &&
853 		    ipsec->rx_tbl[i].vf == vf)
854 			ixgbe_ipsec_del_sa(ipsec->rx_tbl[i].xs);
855 	}
856 
857 	/* search tx sa table */
858 	for (i = 0; i < IXGBE_IPSEC_MAX_SA_COUNT && ipsec->num_tx_sa; i++) {
859 		if (!ipsec->tx_tbl[i].used)
860 			continue;
861 		if (ipsec->tx_tbl[i].mode & IXGBE_RXTXMOD_VF &&
862 		    ipsec->tx_tbl[i].vf == vf)
863 			ixgbe_ipsec_del_sa(ipsec->tx_tbl[i].xs);
864 	}
865 }
866 
867 /**
868  * ixgbe_ipsec_vf_add_sa - translate VF request to SA add
869  * @adapter: board private structure
870  * @msgbuf: The message buffer
871  * @vf: the VF index
872  *
873  * Make up a new xs and algorithm info from the data sent by the VF.
874  * We only need to sketch in just enough to set up the HW offload.
875  * Put the resulting offload_handle into the return message to the VF.
876  *
877  * Returns 0 or error value
878  **/
879 int ixgbe_ipsec_vf_add_sa(struct ixgbe_adapter *adapter, u32 *msgbuf, u32 vf)
880 {
881 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
882 	struct xfrm_algo_desc *algo;
883 	struct sa_mbx_msg *sam;
884 	struct xfrm_state *xs;
885 	size_t aead_len;
886 	u16 sa_idx;
887 	u32 pfsa;
888 	int err;
889 
890 	sam = (struct sa_mbx_msg *)(&msgbuf[1]);
891 	if (!adapter->vfinfo[vf].trusted ||
892 	    !(adapter->flags2 & IXGBE_FLAG2_VF_IPSEC_ENABLED)) {
893 		e_warn(drv, "VF %d attempted to add an IPsec SA\n", vf);
894 		err = -EACCES;
895 		goto err_out;
896 	}
897 
898 	/* Tx IPsec offload doesn't seem to work on this
899 	 * device, so block these requests for now.
900 	 */
901 	if (!(sam->flags & XFRM_OFFLOAD_INBOUND)) {
902 		err = -EOPNOTSUPP;
903 		goto err_out;
904 	}
905 
906 	xs = kzalloc(sizeof(*xs), GFP_KERNEL);
907 	if (unlikely(!xs)) {
908 		err = -ENOMEM;
909 		goto err_out;
910 	}
911 
912 	xs->xso.flags = sam->flags;
913 	xs->id.spi = sam->spi;
914 	xs->id.proto = sam->proto;
915 	xs->props.family = sam->family;
916 	if (xs->props.family == AF_INET6)
917 		memcpy(&xs->id.daddr.a6, sam->addr, sizeof(xs->id.daddr.a6));
918 	else
919 		memcpy(&xs->id.daddr.a4, sam->addr, sizeof(xs->id.daddr.a4));
920 	xs->xso.dev = adapter->netdev;
921 
922 	algo = xfrm_aead_get_byname(aes_gcm_name, IXGBE_IPSEC_AUTH_BITS, 1);
923 	if (unlikely(!algo)) {
924 		err = -ENOENT;
925 		goto err_xs;
926 	}
927 
928 	aead_len = sizeof(*xs->aead) + IXGBE_IPSEC_KEY_BITS / 8;
929 	xs->aead = kzalloc(aead_len, GFP_KERNEL);
930 	if (unlikely(!xs->aead)) {
931 		err = -ENOMEM;
932 		goto err_xs;
933 	}
934 
935 	xs->props.ealgo = algo->desc.sadb_alg_id;
936 	xs->geniv = algo->uinfo.aead.geniv;
937 	xs->aead->alg_icv_len = IXGBE_IPSEC_AUTH_BITS;
938 	xs->aead->alg_key_len = IXGBE_IPSEC_KEY_BITS;
939 	memcpy(xs->aead->alg_key, sam->key, sizeof(sam->key));
940 	memcpy(xs->aead->alg_name, aes_gcm_name, sizeof(aes_gcm_name));
941 
942 	/* set up the HW offload */
943 	err = ixgbe_ipsec_add_sa(xs);
944 	if (err)
945 		goto err_aead;
946 
947 	pfsa = xs->xso.offload_handle;
948 	if (pfsa < IXGBE_IPSEC_BASE_TX_INDEX) {
949 		sa_idx = pfsa - IXGBE_IPSEC_BASE_RX_INDEX;
950 		ipsec->rx_tbl[sa_idx].vf = vf;
951 		ipsec->rx_tbl[sa_idx].mode |= IXGBE_RXTXMOD_VF;
952 	} else {
953 		sa_idx = pfsa - IXGBE_IPSEC_BASE_TX_INDEX;
954 		ipsec->tx_tbl[sa_idx].vf = vf;
955 		ipsec->tx_tbl[sa_idx].mode |= IXGBE_RXTXMOD_VF;
956 	}
957 
958 	msgbuf[1] = xs->xso.offload_handle;
959 
960 	return 0;
961 
962 err_aead:
963 	kfree_sensitive(xs->aead);
964 err_xs:
965 	kfree_sensitive(xs);
966 err_out:
967 	msgbuf[1] = err;
968 	return err;
969 }
970 
971 /**
972  * ixgbe_ipsec_vf_del_sa - translate VF request to SA delete
973  * @adapter: board private structure
974  * @msgbuf: The message buffer
975  * @vf: the VF index
976  *
977  * Given the offload_handle sent by the VF, look for the related SA table
978  * entry and use its xs field to call for a delete of the SA.
979  *
980  * Note: We silently ignore requests to delete entries that are already
981  *       set to unused because when a VF is set to "DOWN", the PF first
982  *       gets a reset and clears all the VF's entries; then the VF's
983  *       XFRM stack sends individual deletes for each entry, which the
984  *       reset already removed.  In the future it might be good to try to
985  *       optimize this so not so many unnecessary delete messages are sent.
986  *
987  * Returns 0 or error value
988  **/
989 int ixgbe_ipsec_vf_del_sa(struct ixgbe_adapter *adapter, u32 *msgbuf, u32 vf)
990 {
991 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
992 	struct xfrm_state *xs;
993 	u32 pfsa = msgbuf[1];
994 	u16 sa_idx;
995 
996 	if (!adapter->vfinfo[vf].trusted) {
997 		e_err(drv, "vf %d attempted to delete an SA\n", vf);
998 		return -EPERM;
999 	}
1000 
1001 	if (pfsa < IXGBE_IPSEC_BASE_TX_INDEX) {
1002 		struct rx_sa *rsa;
1003 
1004 		sa_idx = pfsa - IXGBE_IPSEC_BASE_RX_INDEX;
1005 		if (sa_idx >= IXGBE_IPSEC_MAX_SA_COUNT) {
1006 			e_err(drv, "vf %d SA index %d out of range\n",
1007 			      vf, sa_idx);
1008 			return -EINVAL;
1009 		}
1010 
1011 		rsa = &ipsec->rx_tbl[sa_idx];
1012 
1013 		if (!rsa->used)
1014 			return 0;
1015 
1016 		if (!(rsa->mode & IXGBE_RXTXMOD_VF) ||
1017 		    rsa->vf != vf) {
1018 			e_err(drv, "vf %d bad Rx SA index %d\n", vf, sa_idx);
1019 			return -ENOENT;
1020 		}
1021 
1022 		xs = ipsec->rx_tbl[sa_idx].xs;
1023 	} else {
1024 		struct tx_sa *tsa;
1025 
1026 		sa_idx = pfsa - IXGBE_IPSEC_BASE_TX_INDEX;
1027 		if (sa_idx >= IXGBE_IPSEC_MAX_SA_COUNT) {
1028 			e_err(drv, "vf %d SA index %d out of range\n",
1029 			      vf, sa_idx);
1030 			return -EINVAL;
1031 		}
1032 
1033 		tsa = &ipsec->tx_tbl[sa_idx];
1034 
1035 		if (!tsa->used)
1036 			return 0;
1037 
1038 		if (!(tsa->mode & IXGBE_RXTXMOD_VF) ||
1039 		    tsa->vf != vf) {
1040 			e_err(drv, "vf %d bad Tx SA index %d\n", vf, sa_idx);
1041 			return -ENOENT;
1042 		}
1043 
1044 		xs = ipsec->tx_tbl[sa_idx].xs;
1045 	}
1046 
1047 	ixgbe_ipsec_del_sa(xs);
1048 
1049 	/* remove the xs that was made-up in the add request */
1050 	kfree_sensitive(xs);
1051 
1052 	return 0;
1053 }
1054 
1055 /**
1056  * ixgbe_ipsec_tx - setup Tx flags for ipsec offload
1057  * @tx_ring: outgoing context
1058  * @first: current data packet
1059  * @itd: ipsec Tx data for later use in building context descriptor
1060  **/
1061 int ixgbe_ipsec_tx(struct ixgbe_ring *tx_ring,
1062 		   struct ixgbe_tx_buffer *first,
1063 		   struct ixgbe_ipsec_tx_data *itd)
1064 {
1065 	struct ixgbe_adapter *adapter = netdev_priv(tx_ring->netdev);
1066 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
1067 	struct xfrm_state *xs;
1068 	struct sec_path *sp;
1069 	struct tx_sa *tsa;
1070 
1071 	sp = skb_sec_path(first->skb);
1072 	if (unlikely(!sp->len)) {
1073 		netdev_err(tx_ring->netdev, "%s: no xfrm state len = %d\n",
1074 			   __func__, sp->len);
1075 		return 0;
1076 	}
1077 
1078 	xs = xfrm_input_state(first->skb);
1079 	if (unlikely(!xs)) {
1080 		netdev_err(tx_ring->netdev, "%s: no xfrm_input_state() xs = %p\n",
1081 			   __func__, xs);
1082 		return 0;
1083 	}
1084 
1085 	itd->sa_idx = xs->xso.offload_handle - IXGBE_IPSEC_BASE_TX_INDEX;
1086 	if (unlikely(itd->sa_idx >= IXGBE_IPSEC_MAX_SA_COUNT)) {
1087 		netdev_err(tx_ring->netdev, "%s: bad sa_idx=%d handle=%lu\n",
1088 			   __func__, itd->sa_idx, xs->xso.offload_handle);
1089 		return 0;
1090 	}
1091 
1092 	tsa = &ipsec->tx_tbl[itd->sa_idx];
1093 	if (unlikely(!tsa->used)) {
1094 		netdev_err(tx_ring->netdev, "%s: unused sa_idx=%d\n",
1095 			   __func__, itd->sa_idx);
1096 		return 0;
1097 	}
1098 
1099 	first->tx_flags |= IXGBE_TX_FLAGS_IPSEC | IXGBE_TX_FLAGS_CC;
1100 
1101 	if (xs->id.proto == IPPROTO_ESP) {
1102 
1103 		itd->flags |= IXGBE_ADVTXD_TUCMD_IPSEC_TYPE_ESP |
1104 			      IXGBE_ADVTXD_TUCMD_L4T_TCP;
1105 		if (first->protocol == htons(ETH_P_IP))
1106 			itd->flags |= IXGBE_ADVTXD_TUCMD_IPV4;
1107 
1108 		/* The actual trailer length is authlen (16 bytes) plus
1109 		 * 2 bytes for the proto and the padlen values, plus
1110 		 * padlen bytes of padding.  This ends up not the same
1111 		 * as the static value found in xs->props.trailer_len (21).
1112 		 *
1113 		 * ... but if we're doing GSO, don't bother as the stack
1114 		 * doesn't add a trailer for those.
1115 		 */
1116 		if (!skb_is_gso(first->skb)) {
1117 			/* The "correct" way to get the auth length would be
1118 			 * to use
1119 			 *    authlen = crypto_aead_authsize(xs->data);
1120 			 * but since we know we only have one size to worry
1121 			 * about * we can let the compiler use the constant
1122 			 * and save us a few CPU cycles.
1123 			 */
1124 			const int authlen = IXGBE_IPSEC_AUTH_BITS / 8;
1125 			struct sk_buff *skb = first->skb;
1126 			u8 padlen;
1127 			int ret;
1128 
1129 			ret = skb_copy_bits(skb, skb->len - (authlen + 2),
1130 					    &padlen, 1);
1131 			if (unlikely(ret))
1132 				return 0;
1133 			itd->trailer_len = authlen + 2 + padlen;
1134 		}
1135 	}
1136 	if (tsa->encrypt)
1137 		itd->flags |= IXGBE_ADVTXD_TUCMD_IPSEC_ENCRYPT_EN;
1138 
1139 	return 1;
1140 }
1141 
1142 /**
1143  * ixgbe_ipsec_rx - decode ipsec bits from Rx descriptor
1144  * @rx_ring: receiving ring
1145  * @rx_desc: receive data descriptor
1146  * @skb: current data packet
1147  *
1148  * Determine if there was an ipsec encapsulation noticed, and if so set up
1149  * the resulting status for later in the receive stack.
1150  **/
1151 void ixgbe_ipsec_rx(struct ixgbe_ring *rx_ring,
1152 		    union ixgbe_adv_rx_desc *rx_desc,
1153 		    struct sk_buff *skb)
1154 {
1155 	struct ixgbe_adapter *adapter = netdev_priv(rx_ring->netdev);
1156 	__le16 pkt_info = rx_desc->wb.lower.lo_dword.hs_rss.pkt_info;
1157 	__le16 ipsec_pkt_types = cpu_to_le16(IXGBE_RXDADV_PKTTYPE_IPSEC_AH |
1158 					     IXGBE_RXDADV_PKTTYPE_IPSEC_ESP);
1159 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
1160 	struct xfrm_offload *xo = NULL;
1161 	struct xfrm_state *xs = NULL;
1162 	struct ipv6hdr *ip6 = NULL;
1163 	struct iphdr *ip4 = NULL;
1164 	struct sec_path *sp;
1165 	void *daddr;
1166 	__be32 spi;
1167 	u8 *c_hdr;
1168 	u8 proto;
1169 
1170 	/* Find the ip and crypto headers in the data.
1171 	 * We can assume no vlan header in the way, b/c the
1172 	 * hw won't recognize the IPsec packet and anyway the
1173 	 * currently vlan device doesn't support xfrm offload.
1174 	 */
1175 	if (pkt_info & cpu_to_le16(IXGBE_RXDADV_PKTTYPE_IPV4)) {
1176 		ip4 = (struct iphdr *)(skb->data + ETH_HLEN);
1177 		daddr = &ip4->daddr;
1178 		c_hdr = (u8 *)ip4 + ip4->ihl * 4;
1179 	} else if (pkt_info & cpu_to_le16(IXGBE_RXDADV_PKTTYPE_IPV6)) {
1180 		ip6 = (struct ipv6hdr *)(skb->data + ETH_HLEN);
1181 		daddr = &ip6->daddr;
1182 		c_hdr = (u8 *)ip6 + sizeof(struct ipv6hdr);
1183 	} else {
1184 		return;
1185 	}
1186 
1187 	switch (pkt_info & ipsec_pkt_types) {
1188 	case cpu_to_le16(IXGBE_RXDADV_PKTTYPE_IPSEC_AH):
1189 		spi = ((struct ip_auth_hdr *)c_hdr)->spi;
1190 		proto = IPPROTO_AH;
1191 		break;
1192 	case cpu_to_le16(IXGBE_RXDADV_PKTTYPE_IPSEC_ESP):
1193 		spi = ((struct ip_esp_hdr *)c_hdr)->spi;
1194 		proto = IPPROTO_ESP;
1195 		break;
1196 	default:
1197 		return;
1198 	}
1199 
1200 	xs = ixgbe_ipsec_find_rx_state(ipsec, daddr, proto, spi, !!ip4);
1201 	if (unlikely(!xs))
1202 		return;
1203 
1204 	sp = secpath_set(skb);
1205 	if (unlikely(!sp))
1206 		return;
1207 
1208 	sp->xvec[sp->len++] = xs;
1209 	sp->olen++;
1210 	xo = xfrm_offload(skb);
1211 	xo->flags = CRYPTO_DONE;
1212 	xo->status = CRYPTO_SUCCESS;
1213 
1214 	adapter->rx_ipsec++;
1215 }
1216 
1217 /**
1218  * ixgbe_init_ipsec_offload - initialize security registers for IPSec operation
1219  * @adapter: board private structure
1220  **/
1221 void ixgbe_init_ipsec_offload(struct ixgbe_adapter *adapter)
1222 {
1223 	struct ixgbe_hw *hw = &adapter->hw;
1224 	struct ixgbe_ipsec *ipsec;
1225 	u32 t_dis, r_dis;
1226 	size_t size;
1227 
1228 	if (hw->mac.type == ixgbe_mac_82598EB)
1229 		return;
1230 
1231 	/* If there is no support for either Tx or Rx offload
1232 	 * we should not be advertising support for IPsec.
1233 	 */
1234 	t_dis = IXGBE_READ_REG(hw, IXGBE_SECTXSTAT) &
1235 		IXGBE_SECTXSTAT_SECTX_OFF_DIS;
1236 	r_dis = IXGBE_READ_REG(hw, IXGBE_SECRXSTAT) &
1237 		IXGBE_SECRXSTAT_SECRX_OFF_DIS;
1238 	if (t_dis || r_dis)
1239 		return;
1240 
1241 	ipsec = kzalloc(sizeof(*ipsec), GFP_KERNEL);
1242 	if (!ipsec)
1243 		goto err1;
1244 	hash_init(ipsec->rx_sa_list);
1245 
1246 	size = sizeof(struct rx_sa) * IXGBE_IPSEC_MAX_SA_COUNT;
1247 	ipsec->rx_tbl = kzalloc(size, GFP_KERNEL);
1248 	if (!ipsec->rx_tbl)
1249 		goto err2;
1250 
1251 	size = sizeof(struct tx_sa) * IXGBE_IPSEC_MAX_SA_COUNT;
1252 	ipsec->tx_tbl = kzalloc(size, GFP_KERNEL);
1253 	if (!ipsec->tx_tbl)
1254 		goto err2;
1255 
1256 	size = sizeof(struct rx_ip_sa) * IXGBE_IPSEC_MAX_RX_IP_COUNT;
1257 	ipsec->ip_tbl = kzalloc(size, GFP_KERNEL);
1258 	if (!ipsec->ip_tbl)
1259 		goto err2;
1260 
1261 	ipsec->num_rx_sa = 0;
1262 	ipsec->num_tx_sa = 0;
1263 
1264 	adapter->ipsec = ipsec;
1265 	ixgbe_ipsec_stop_engine(adapter);
1266 	ixgbe_ipsec_clear_hw_tables(adapter);
1267 
1268 	adapter->netdev->xfrmdev_ops = &ixgbe_xfrmdev_ops;
1269 
1270 	return;
1271 
1272 err2:
1273 	kfree(ipsec->ip_tbl);
1274 	kfree(ipsec->rx_tbl);
1275 	kfree(ipsec->tx_tbl);
1276 	kfree(ipsec);
1277 err1:
1278 	netdev_err(adapter->netdev, "Unable to allocate memory for SA tables");
1279 }
1280 
1281 /**
1282  * ixgbe_stop_ipsec_offload - tear down the ipsec offload
1283  * @adapter: board private structure
1284  **/
1285 void ixgbe_stop_ipsec_offload(struct ixgbe_adapter *adapter)
1286 {
1287 	struct ixgbe_ipsec *ipsec = adapter->ipsec;
1288 
1289 	adapter->ipsec = NULL;
1290 	if (ipsec) {
1291 		kfree(ipsec->ip_tbl);
1292 		kfree(ipsec->rx_tbl);
1293 		kfree(ipsec->tx_tbl);
1294 		kfree(ipsec);
1295 	}
1296 }
1297