drivers/net/ethernet/netronome/nfp/crypto/tls.c

   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 }