xref: /linux/drivers/net/ethernet/netronome/nfp/crypto/tls.c (revision 0f93242d96ff5a04fe02c4978e8dddb014235971)
1 // SPDX-License-Identifier: (GPL-2.0-only OR BSD-2-Clause)
2 /* Copyright (C) 2019 Netronome Systems, Inc. */
3 
4 #include <linux/bitfield.h>
5 #include <linux/ipv6.h>
6 #include <linux/skbuff.h>
7 #include <net/tls.h>
8 
9 #include "../ccm.h"
10 #include "../nfp_net.h"
11 #include "crypto.h"
12 #include "fw.h"
13 
14 #define NFP_NET_TLS_CCM_MBOX_OPS_MASK		\
15 	(BIT(NFP_CCM_TYPE_CRYPTO_RESET) |	\
16 	 BIT(NFP_CCM_TYPE_CRYPTO_ADD) |		\
17 	 BIT(NFP_CCM_TYPE_CRYPTO_DEL) |		\
18 	 BIT(NFP_CCM_TYPE_CRYPTO_UPDATE))
19 
20 #define NFP_NET_TLS_OPCODE_MASK_RX			\
21 	BIT(NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_DEC)
22 
23 #define NFP_NET_TLS_OPCODE_MASK_TX			\
24 	BIT(NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_ENC)
25 
26 #define NFP_NET_TLS_OPCODE_MASK						\
27 	(NFP_NET_TLS_OPCODE_MASK_RX | NFP_NET_TLS_OPCODE_MASK_TX)
28 
29 static void nfp_net_crypto_set_op(struct nfp_net *nn, u8 opcode, bool on)
30 {
31 	u32 off, val;
32 
33 	off = nn->tlv_caps.crypto_enable_off + round_down(opcode / 8, 4);
34 
35 	val = nn_readl(nn, off);
36 	if (on)
37 		val |= BIT(opcode & 31);
38 	else
39 		val &= ~BIT(opcode & 31);
40 	nn_writel(nn, off, val);
41 }
42 
43 static bool
44 __nfp_net_tls_conn_cnt_changed(struct nfp_net *nn, int add,
45 			       enum tls_offload_ctx_dir direction)
46 {
47 	u8 opcode;
48 	int cnt;
49 
50 	if (direction == TLS_OFFLOAD_CTX_DIR_TX) {
51 		opcode = NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_ENC;
52 		nn->ktls_tx_conn_cnt += add;
53 		cnt = nn->ktls_tx_conn_cnt;
54 		nn->dp.ktls_tx = !!nn->ktls_tx_conn_cnt;
55 	} else {
56 		opcode = NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_DEC;
57 		nn->ktls_rx_conn_cnt += add;
58 		cnt = nn->ktls_rx_conn_cnt;
59 	}
60 
61 	/* Care only about 0 -> 1 and 1 -> 0 transitions */
62 	if (cnt > 1)
63 		return false;
64 
65 	nfp_net_crypto_set_op(nn, opcode, cnt);
66 	return true;
67 }
68 
69 static int
70 nfp_net_tls_conn_cnt_changed(struct nfp_net *nn, int add,
71 			     enum tls_offload_ctx_dir direction)
72 {
73 	int ret = 0;
74 
75 	/* Use the BAR lock to protect the connection counts */
76 	nn_ctrl_bar_lock(nn);
77 	if (__nfp_net_tls_conn_cnt_changed(nn, add, direction)) {
78 		ret = __nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_CRYPTO);
79 		/* Undo the cnt adjustment if failed */
80 		if (ret)
81 			__nfp_net_tls_conn_cnt_changed(nn, -add, direction);
82 	}
83 	nn_ctrl_bar_unlock(nn);
84 
85 	return ret;
86 }
87 
88 static int
89 nfp_net_tls_conn_add(struct nfp_net *nn, enum tls_offload_ctx_dir direction)
90 {
91 	return nfp_net_tls_conn_cnt_changed(nn, 1, direction);
92 }
93 
94 static int
95 nfp_net_tls_conn_remove(struct nfp_net *nn, enum tls_offload_ctx_dir direction)
96 {
97 	return nfp_net_tls_conn_cnt_changed(nn, -1, direction);
98 }
99 
100 static struct sk_buff *
101 nfp_net_tls_alloc_simple(struct nfp_net *nn, size_t req_sz, gfp_t flags)
102 {
103 	return nfp_ccm_mbox_msg_alloc(nn, req_sz,
104 				      sizeof(struct nfp_crypto_reply_simple),
105 				      flags);
106 }
107 
108 static int
109 nfp_net_tls_communicate_simple(struct nfp_net *nn, struct sk_buff *skb,
110 			       const char *name, enum nfp_ccm_type type)
111 {
112 	struct nfp_crypto_reply_simple *reply;
113 	int err;
114 
115 	err = __nfp_ccm_mbox_communicate(nn, skb, type,
116 					 sizeof(*reply), sizeof(*reply),
117 					 type == NFP_CCM_TYPE_CRYPTO_DEL);
118 	if (err) {
119 		nn_dp_warn(&nn->dp, "failed to %s TLS: %d\n", name, err);
120 		return err;
121 	}
122 
123 	reply = (void *)skb->data;
124 	err = -be32_to_cpu(reply->error);
125 	if (err)
126 		nn_dp_warn(&nn->dp, "failed to %s TLS, fw replied: %d\n",
127 			   name, err);
128 	dev_consume_skb_any(skb);
129 
130 	return err;
131 }
132 
133 static void nfp_net_tls_del_fw(struct nfp_net *nn, __be32 *fw_handle)
134 {
135 	struct nfp_crypto_req_del *req;
136 	struct sk_buff *skb;
137 
138 	skb = nfp_net_tls_alloc_simple(nn, sizeof(*req), GFP_KERNEL);
139 	if (!skb)
140 		return;
141 
142 	req = (void *)skb->data;
143 	req->ep_id = 0;
144 	memcpy(req->handle, fw_handle, sizeof(req->handle));
145 
146 	nfp_net_tls_communicate_simple(nn, skb, "delete",
147 				       NFP_CCM_TYPE_CRYPTO_DEL);
148 }
149 
150 static struct nfp_crypto_req_add_back *
151 nfp_net_tls_set_ipv4(struct nfp_crypto_req_add_v4 *req, struct sock *sk,
152 		     int direction)
153 {
154 	struct inet_sock *inet = inet_sk(sk);
155 
156 	req->front.key_len += sizeof(__be32) * 2;
157 	req->front.ipver_vlan = cpu_to_be16(FIELD_PREP(NFP_NET_TLS_IPVER, 4) |
158 					    FIELD_PREP(NFP_NET_TLS_VLAN,
159 						       NFP_NET_TLS_VLAN_UNUSED));
160 
161 	if (direction == TLS_OFFLOAD_CTX_DIR_TX) {
162 		req->src_ip = inet->inet_saddr;
163 		req->dst_ip = inet->inet_daddr;
164 	} else {
165 		req->src_ip = inet->inet_daddr;
166 		req->dst_ip = inet->inet_saddr;
167 	}
168 
169 	return &req->back;
170 }
171 
172 static struct nfp_crypto_req_add_back *
173 nfp_net_tls_set_ipv6(struct nfp_crypto_req_add_v6 *req, struct sock *sk,
174 		     int direction)
175 {
176 #if IS_ENABLED(CONFIG_IPV6)
177 	struct ipv6_pinfo *np = inet6_sk(sk);
178 
179 	req->front.key_len += sizeof(struct in6_addr) * 2;
180 	req->front.ipver_vlan = cpu_to_be16(FIELD_PREP(NFP_NET_TLS_IPVER, 6) |
181 					    FIELD_PREP(NFP_NET_TLS_VLAN,
182 						       NFP_NET_TLS_VLAN_UNUSED));
183 
184 	if (direction == TLS_OFFLOAD_CTX_DIR_TX) {
185 		memcpy(req->src_ip, &np->saddr, sizeof(req->src_ip));
186 		memcpy(req->dst_ip, &sk->sk_v6_daddr, sizeof(req->dst_ip));
187 	} else {
188 		memcpy(req->src_ip, &sk->sk_v6_daddr, sizeof(req->src_ip));
189 		memcpy(req->dst_ip, &np->saddr, sizeof(req->dst_ip));
190 	}
191 
192 #endif
193 	return &req->back;
194 }
195 
196 static void
197 nfp_net_tls_set_l4(struct nfp_crypto_req_add_front *front,
198 		   struct nfp_crypto_req_add_back *back, struct sock *sk,
199 		   int direction)
200 {
201 	struct inet_sock *inet = inet_sk(sk);
202 
203 	front->l4_proto = IPPROTO_TCP;
204 
205 	if (direction == TLS_OFFLOAD_CTX_DIR_TX) {
206 		back->src_port = inet->inet_sport;
207 		back->dst_port = inet->inet_dport;
208 	} else {
209 		back->src_port = inet->inet_dport;
210 		back->dst_port = inet->inet_sport;
211 	}
212 }
213 
214 static u8 nfp_tls_1_2_dir_to_opcode(enum tls_offload_ctx_dir direction)
215 {
216 	switch (direction) {
217 	case TLS_OFFLOAD_CTX_DIR_TX:
218 		return NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_ENC;
219 	case TLS_OFFLOAD_CTX_DIR_RX:
220 		return NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_DEC;
221 	default:
222 		WARN_ON_ONCE(1);
223 		return 0;
224 	}
225 }
226 
227 static bool
228 nfp_net_cipher_supported(struct nfp_net *nn, u16 cipher_type,
229 			 enum tls_offload_ctx_dir direction)
230 {
231 	u8 bit;
232 
233 	switch (cipher_type) {
234 	case TLS_CIPHER_AES_GCM_128:
235 		if (direction == TLS_OFFLOAD_CTX_DIR_TX)
236 			bit = NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_ENC;
237 		else
238 			bit = NFP_NET_CRYPTO_OP_TLS_1_2_AES_GCM_128_DEC;
239 		break;
240 	default:
241 		return false;
242 	}
243 
244 	return nn->tlv_caps.crypto_ops & BIT(bit);
245 }
246 
247 static int
248 nfp_net_tls_add(struct net_device *netdev, struct sock *sk,
249 		enum tls_offload_ctx_dir direction,
250 		struct tls_crypto_info *crypto_info,
251 		u32 start_offload_tcp_sn)
252 {
253 	struct tls12_crypto_info_aes_gcm_128 *tls_ci;
254 	struct nfp_net *nn = netdev_priv(netdev);
255 	struct nfp_crypto_req_add_front *front;
256 	struct nfp_net_tls_offload_ctx *ntls;
257 	struct nfp_crypto_req_add_back *back;
258 	struct nfp_crypto_reply_add *reply;
259 	struct sk_buff *skb;
260 	size_t req_sz;
261 	bool ipv6;
262 	int err;
263 
264 	BUILD_BUG_ON(sizeof(struct nfp_net_tls_offload_ctx) >
265 		     TLS_DRIVER_STATE_SIZE_TX);
266 	BUILD_BUG_ON(offsetof(struct nfp_net_tls_offload_ctx, rx_end) >
267 		     TLS_DRIVER_STATE_SIZE_RX);
268 
269 	if (!nfp_net_cipher_supported(nn, crypto_info->cipher_type, direction))
270 		return -EOPNOTSUPP;
271 
272 	switch (sk->sk_family) {
273 #if IS_ENABLED(CONFIG_IPV6)
274 	case AF_INET6:
275 		if (sk->sk_ipv6only ||
276 		    ipv6_addr_type(&sk->sk_v6_daddr) != IPV6_ADDR_MAPPED) {
277 			req_sz = sizeof(struct nfp_crypto_req_add_v6);
278 			ipv6 = true;
279 			break;
280 		}
281 #endif
282 		/* fall through */
283 	case AF_INET:
284 		req_sz = sizeof(struct nfp_crypto_req_add_v4);
285 		ipv6 = false;
286 		break;
287 	default:
288 		return -EOPNOTSUPP;
289 	}
290 
291 	err = nfp_net_tls_conn_add(nn, direction);
292 	if (err)
293 		return err;
294 
295 	skb = nfp_ccm_mbox_msg_alloc(nn, req_sz, sizeof(*reply), GFP_KERNEL);
296 	if (!skb) {
297 		err = -ENOMEM;
298 		goto err_conn_remove;
299 	}
300 
301 	front = (void *)skb->data;
302 	front->ep_id = 0;
303 	front->key_len = 8;
304 	front->opcode = nfp_tls_1_2_dir_to_opcode(direction);
305 	memset(front->resv, 0, sizeof(front->resv));
306 
307 	if (ipv6)
308 		back = nfp_net_tls_set_ipv6((void *)skb->data, sk, direction);
309 	else
310 		back = nfp_net_tls_set_ipv4((void *)skb->data, sk, direction);
311 
312 	nfp_net_tls_set_l4(front, back, sk, direction);
313 
314 	back->counter = 0;
315 	back->tcp_seq = cpu_to_be32(start_offload_tcp_sn);
316 
317 	tls_ci = (struct tls12_crypto_info_aes_gcm_128 *)crypto_info;
318 	memcpy(back->key, tls_ci->key, TLS_CIPHER_AES_GCM_128_KEY_SIZE);
319 	memset(&back->key[TLS_CIPHER_AES_GCM_128_KEY_SIZE / 4], 0,
320 	       sizeof(back->key) - TLS_CIPHER_AES_GCM_128_KEY_SIZE);
321 	memcpy(back->iv, tls_ci->iv, TLS_CIPHER_AES_GCM_128_IV_SIZE);
322 	memcpy(&back->salt, tls_ci->salt, TLS_CIPHER_AES_GCM_128_SALT_SIZE);
323 	memcpy(back->rec_no, tls_ci->rec_seq, sizeof(tls_ci->rec_seq));
324 
325 	err = nfp_ccm_mbox_communicate(nn, skb, NFP_CCM_TYPE_CRYPTO_ADD,
326 				       sizeof(*reply), sizeof(*reply));
327 	if (err) {
328 		nn_dp_warn(&nn->dp, "failed to add TLS: %d\n", err);
329 		/* communicate frees skb on error */
330 		goto err_conn_remove;
331 	}
332 
333 	reply = (void *)skb->data;
334 	err = -be32_to_cpu(reply->error);
335 	if (err) {
336 		if (err == -ENOSPC) {
337 			if (!atomic_fetch_inc(&nn->ktls_no_space))
338 				nn_info(nn, "HW TLS table full\n");
339 		} else {
340 			nn_dp_warn(&nn->dp,
341 				   "failed to add TLS, FW replied: %d\n", err);
342 		}
343 		goto err_free_skb;
344 	}
345 
346 	if (!reply->handle[0] && !reply->handle[1]) {
347 		nn_dp_warn(&nn->dp, "FW returned NULL handle\n");
348 		err = -EINVAL;
349 		goto err_fw_remove;
350 	}
351 
352 	ntls = tls_driver_ctx(sk, direction);
353 	memcpy(ntls->fw_handle, reply->handle, sizeof(ntls->fw_handle));
354 	if (direction == TLS_OFFLOAD_CTX_DIR_TX)
355 		ntls->next_seq = start_offload_tcp_sn;
356 	dev_consume_skb_any(skb);
357 
358 	if (direction == TLS_OFFLOAD_CTX_DIR_TX)
359 		return 0;
360 
361 	tls_offload_rx_resync_set_type(sk,
362 				       TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT);
363 	return 0;
364 
365 err_fw_remove:
366 	nfp_net_tls_del_fw(nn, reply->handle);
367 err_free_skb:
368 	dev_consume_skb_any(skb);
369 err_conn_remove:
370 	nfp_net_tls_conn_remove(nn, direction);
371 	return err;
372 }
373 
374 static void
375 nfp_net_tls_del(struct net_device *netdev, struct tls_context *tls_ctx,
376 		enum tls_offload_ctx_dir direction)
377 {
378 	struct nfp_net *nn = netdev_priv(netdev);
379 	struct nfp_net_tls_offload_ctx *ntls;
380 
381 	nfp_net_tls_conn_remove(nn, direction);
382 
383 	ntls = __tls_driver_ctx(tls_ctx, direction);
384 	nfp_net_tls_del_fw(nn, ntls->fw_handle);
385 }
386 
387 static void
388 nfp_net_tls_resync(struct net_device *netdev, struct sock *sk, u32 seq,
389 		   u8 *rcd_sn, enum tls_offload_ctx_dir direction)
390 {
391 	struct nfp_net *nn = netdev_priv(netdev);
392 	struct nfp_net_tls_offload_ctx *ntls;
393 	struct nfp_crypto_req_update *req;
394 	struct sk_buff *skb;
395 	gfp_t flags;
396 
397 	flags = direction == TLS_OFFLOAD_CTX_DIR_TX ? GFP_KERNEL : GFP_ATOMIC;
398 	skb = nfp_net_tls_alloc_simple(nn, sizeof(*req), flags);
399 	if (!skb)
400 		return;
401 
402 	ntls = tls_driver_ctx(sk, direction);
403 	req = (void *)skb->data;
404 	req->ep_id = 0;
405 	req->opcode = nfp_tls_1_2_dir_to_opcode(direction);
406 	memset(req->resv, 0, sizeof(req->resv));
407 	memcpy(req->handle, ntls->fw_handle, sizeof(ntls->fw_handle));
408 	req->tcp_seq = cpu_to_be32(seq);
409 	memcpy(req->rec_no, rcd_sn, sizeof(req->rec_no));
410 
411 	if (direction == TLS_OFFLOAD_CTX_DIR_TX) {
412 		nfp_net_tls_communicate_simple(nn, skb, "sync",
413 					       NFP_CCM_TYPE_CRYPTO_UPDATE);
414 		ntls->next_seq = seq;
415 	} else {
416 		nfp_ccm_mbox_post(nn, skb, NFP_CCM_TYPE_CRYPTO_UPDATE,
417 				  sizeof(struct nfp_crypto_reply_simple));
418 	}
419 }
420 
421 static const struct tlsdev_ops nfp_net_tls_ops = {
422 	.tls_dev_add = nfp_net_tls_add,
423 	.tls_dev_del = nfp_net_tls_del,
424 	.tls_dev_resync = nfp_net_tls_resync,
425 };
426 
427 static int nfp_net_tls_reset(struct nfp_net *nn)
428 {
429 	struct nfp_crypto_req_reset *req;
430 	struct sk_buff *skb;
431 
432 	skb = nfp_net_tls_alloc_simple(nn, sizeof(*req), GFP_KERNEL);
433 	if (!skb)
434 		return -ENOMEM;
435 
436 	req = (void *)skb->data;
437 	req->ep_id = 0;
438 
439 	return nfp_net_tls_communicate_simple(nn, skb, "reset",
440 					      NFP_CCM_TYPE_CRYPTO_RESET);
441 }
442 
443 int nfp_net_tls_init(struct nfp_net *nn)
444 {
445 	struct net_device *netdev = nn->dp.netdev;
446 	int err;
447 
448 	if (!(nn->tlv_caps.crypto_ops & NFP_NET_TLS_OPCODE_MASK))
449 		return 0;
450 
451 	if ((nn->tlv_caps.mbox_cmsg_types & NFP_NET_TLS_CCM_MBOX_OPS_MASK) !=
452 	    NFP_NET_TLS_CCM_MBOX_OPS_MASK)
453 		return 0;
454 
455 	if (!nfp_ccm_mbox_fits(nn, sizeof(struct nfp_crypto_req_add_v6))) {
456 		nn_warn(nn, "disabling TLS offload - mbox too small: %d\n",
457 			nn->tlv_caps.mbox_len);
458 		return 0;
459 	}
460 
461 	err = nfp_net_tls_reset(nn);
462 	if (err)
463 		return err;
464 
465 	nn_ctrl_bar_lock(nn);
466 	nn_writel(nn, nn->tlv_caps.crypto_enable_off, 0);
467 	err = __nfp_net_reconfig(nn, NFP_NET_CFG_UPDATE_CRYPTO);
468 	nn_ctrl_bar_unlock(nn);
469 	if (err)
470 		return err;
471 
472 	if (nn->tlv_caps.crypto_ops & NFP_NET_TLS_OPCODE_MASK_RX) {
473 		netdev->hw_features |= NETIF_F_HW_TLS_RX;
474 		netdev->features |= NETIF_F_HW_TLS_RX;
475 	}
476 	if (nn->tlv_caps.crypto_ops & NFP_NET_TLS_OPCODE_MASK_TX) {
477 		netdev->hw_features |= NETIF_F_HW_TLS_TX;
478 		netdev->features |= NETIF_F_HW_TLS_TX;
479 	}
480 
481 	netdev->tlsdev_ops = &nfp_net_tls_ops;
482 
483 	return 0;
484 }
485