include/net/tls.h

   1 /*
   2  * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved.
   3  * Copyright (c) 2016-2017, Dave Watson <davejwatson@fb.com>. All rights reserved.
   4  *
   5  * This software is available to you under a choice of one of two
   6  * licenses.  You may choose to be licensed under the terms of the GNU
   7  * General Public License (GPL) Version 2, available from the file
   8  * COPYING in the main directory of this source tree, or the
   9  * OpenIB.org BSD license below:
  10  *
  11  *     Redistribution and use in source and binary forms, with or
  12  *     without modification, are permitted provided that the following
  13  *     conditions are met:
  14  *
  15  *      - Redistributions of source code must retain the above
  16  *        copyright notice, this list of conditions and the following
  17  *        disclaimer.
  18  *
  19  *      - Redistributions in binary form must reproduce the above
  20  *        copyright notice, this list of conditions and the following
  21  *        disclaimer in the documentation and/or other materials
  22  *        provided with the distribution.
  23  *
  24  * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
  25  * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
  26  * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
  27  * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
  28  * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
  29  * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
  30  * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
  31  * SOFTWARE.
  32  */
  33
  34 #ifndef _TLS_OFFLOAD_H
  35 #define _TLS_OFFLOAD_H
  36
  37 #include <linux/types.h>
  38 #include <asm/byteorder.h>
  39 #include <linux/crypto.h>
  40 #include <linux/socket.h>
  41 #include <linux/tcp.h>
  42 #include <net/tcp.h>
  43 #include <net/strparser.h>
  44
  45 #include <uapi/linux/tls.h>
  46
  47
  48 /* Maximum data size carried in a TLS record */
  49 #define TLS_MAX_PAYLOAD_SIZE            ((size_t)1 << 14)
  50
  51 #define TLS_HEADER_SIZE                 5
  52 #define TLS_NONCE_OFFSET                TLS_HEADER_SIZE
  53
  54 #define TLS_CRYPTO_INFO_READY(info)     ((info)->cipher_type)
  55
  56 #define TLS_RECORD_TYPE_DATA            0x17
  57
  58 #define TLS_AAD_SPACE_SIZE              13
  59 #define TLS_DEVICE_NAME_MAX             32
  60
  61 /*
  62  * This structure defines the routines for Inline TLS driver.
  63  * The following routines are optional and filled with a
  64  * null pointer if not defined.
  65  *
  66  * @name: Its the name of registered Inline tls device
  67  * @dev_list: Inline tls device list
  68  * int (*feature)(struct tls_device *device);
  69  *     Called to return Inline TLS driver capability
  70  *
  71  * int (*hash)(struct tls_device *device, struct sock *sk);
  72  *     This function sets Inline driver for listen and program
  73  *     device specific functioanlity as required
  74  *
  75  * void (*unhash)(struct tls_device *device, struct sock *sk);
  76  *     This function cleans listen state set by Inline TLS driver
  77  */
  78 struct tls_device {
  79         char name[TLS_DEVICE_NAME_MAX];
  80         struct list_head dev_list;
  81         int  (*feature)(struct tls_device *device);
  82         int  (*hash)(struct tls_device *device, struct sock *sk);
  83         void (*unhash)(struct tls_device *device, struct sock *sk);
  84 };
  85
  86 struct tls_sw_context {
  87         struct crypto_aead *aead_send;
  88         struct crypto_aead *aead_recv;
  89         struct crypto_wait async_wait;
  90
  91         /* Receive context */
  92         struct strparser strp;
  93         void (*saved_data_ready)(struct sock *sk);
  94         unsigned int (*sk_poll)(struct file *file, struct socket *sock,
  95                                 struct poll_table_struct *wait);
  96         struct sk_buff *recv_pkt;
  97         u8 control;
  98         bool decrypted;
  99
 100         /* Sending context */
 101         char aad_space[TLS_AAD_SPACE_SIZE];
 102
 103         unsigned int sg_plaintext_size;
 104         int sg_plaintext_num_elem;
 105         struct scatterlist sg_plaintext_data[MAX_SKB_FRAGS];
 106
 107         unsigned int sg_encrypted_size;
 108         int sg_encrypted_num_elem;
 109         struct scatterlist sg_encrypted_data[MAX_SKB_FRAGS];
 110
 111         /* AAD | sg_plaintext_data | sg_tag */
 112         struct scatterlist sg_aead_in[2];
 113         /* AAD | sg_encrypted_data (data contain overhead for hdr&iv&tag) */
 114         struct scatterlist sg_aead_out[2];
 115 };
 116
 117 enum {
 118         TLS_PENDING_CLOSED_RECORD
 119 };
 120
 121 struct cipher_context {
 122         u16 prepend_size;
 123         u16 tag_size;
 124         u16 overhead_size;
 125         u16 iv_size;
 126         char *iv;
 127         u16 rec_seq_size;
 128         char *rec_seq;
 129 };
 130
 131 struct tls_context {
 132         union {
 133                 struct tls_crypto_info crypto_send;
 134                 struct tls12_crypto_info_aes_gcm_128 crypto_send_aes_gcm_128;
 135         };
 136         union {
 137                 struct tls_crypto_info crypto_recv;
 138                 struct tls12_crypto_info_aes_gcm_128 crypto_recv_aes_gcm_128;
 139         };
 140
 141         void *priv_ctx;
 142
 143         u8 conf:3;
 144
 145         struct cipher_context tx;
 146         struct cipher_context rx;
 147
 148         struct scatterlist *partially_sent_record;
 149         u16 partially_sent_offset;
 150         unsigned long flags;
 151
 152         u16 pending_open_record_frags;
 153         int (*push_pending_record)(struct sock *sk, int flags);
 154
 155         void (*sk_write_space)(struct sock *sk);
 156         void (*sk_proto_close)(struct sock *sk, long timeout);
 157
 158         int  (*setsockopt)(struct sock *sk, int level,
 159                            int optname, char __user *optval,
 160                            unsigned int optlen);
 161         int  (*getsockopt)(struct sock *sk, int level,
 162                            int optname, char __user *optval,
 163                            int __user *optlen);
 164         int  (*hash)(struct sock *sk);
 165         void (*unhash)(struct sock *sk);
 166 };
 167
 168 int wait_on_pending_writer(struct sock *sk, long *timeo);
 169 int tls_sk_query(struct sock *sk, int optname, char __user *optval,
 170                 int __user *optlen);
 171 int tls_sk_attach(struct sock *sk, int optname, char __user *optval,
 172                   unsigned int optlen);
 173
 174
 175 int tls_set_sw_offload(struct sock *sk, struct tls_context *ctx, int tx);
 176 int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size);
 177 int tls_sw_sendpage(struct sock *sk, struct page *page,
 178                     int offset, size_t size, int flags);
 179 void tls_sw_close(struct sock *sk, long timeout);
 180 void tls_sw_free_resources(struct sock *sk);
 181 int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len,
 182                    int nonblock, int flags, int *addr_len);
 183 unsigned int tls_sw_poll(struct file *file, struct socket *sock,
 184                          struct poll_table_struct *wait);
 185 ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos,
 186                            struct pipe_inode_info *pipe,
 187                            size_t len, unsigned int flags);
 188
 189 void tls_sk_destruct(struct sock *sk, struct tls_context *ctx);
 190 void tls_icsk_clean_acked(struct sock *sk);
 191
 192 int tls_push_sg(struct sock *sk, struct tls_context *ctx,
 193                 struct scatterlist *sg, u16 first_offset,
 194                 int flags);
 195 int tls_push_pending_closed_record(struct sock *sk, struct tls_context *ctx,
 196                                    int flags, long *timeo);
 197
 198 static inline bool tls_is_pending_closed_record(struct tls_context *ctx)
 199 {
 200         return test_bit(TLS_PENDING_CLOSED_RECORD, &ctx->flags);
 201 }
 202
 203 static inline int tls_complete_pending_work(struct sock *sk,
 204                                             struct tls_context *ctx,
 205                                             int flags, long *timeo)
 206 {
 207         int rc = 0;
 208
 209         if (unlikely(sk->sk_write_pending))
 210                 rc = wait_on_pending_writer(sk, timeo);
 211
 212         if (!rc && tls_is_pending_closed_record(ctx))
 213                 rc = tls_push_pending_closed_record(sk, ctx, flags, timeo);
 214
 215         return rc;
 216 }
 217
 218 static inline bool tls_is_partially_sent_record(struct tls_context *ctx)
 219 {
 220         return !!ctx->partially_sent_record;
 221 }
 222
 223 static inline bool tls_is_pending_open_record(struct tls_context *tls_ctx)
 224 {
 225         return tls_ctx->pending_open_record_frags;
 226 }
 227
 228 static inline void tls_err_abort(struct sock *sk, int err)
 229 {
 230         sk->sk_err = err;
 231         sk->sk_error_report(sk);
 232 }
 233
 234 static inline bool tls_bigint_increment(unsigned char *seq, int len)
 235 {
 236         int i;
 237
 238         for (i = len - 1; i >= 0; i--) {
 239                 ++seq[i];
 240                 if (seq[i] != 0)
 241                         break;
 242         }
 243
 244         return (i == -1);
 245 }
 246
 247 static inline void tls_advance_record_sn(struct sock *sk,
 248                                          struct cipher_context *ctx)
 249 {
 250         if (tls_bigint_increment(ctx->rec_seq, ctx->rec_seq_size))
 251                 tls_err_abort(sk, EBADMSG);
 252         tls_bigint_increment(ctx->iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE,
 253                              ctx->iv_size);
 254 }
 255
 256 static inline void tls_fill_prepend(struct tls_context *ctx,
 257                              char *buf,
 258                              size_t plaintext_len,
 259                              unsigned char record_type)
 260 {
 261         size_t pkt_len, iv_size = ctx->tx.iv_size;
 262
 263         pkt_len = plaintext_len + iv_size + ctx->tx.tag_size;
 264
 265         /* we cover nonce explicit here as well, so buf should be of
 266          * size KTLS_DTLS_HEADER_SIZE + KTLS_DTLS_NONCE_EXPLICIT_SIZE
 267          */
 268         buf[0] = record_type;
 269         buf[1] = TLS_VERSION_MINOR(ctx->crypto_send.version);
 270         buf[2] = TLS_VERSION_MAJOR(ctx->crypto_send.version);
 271         /* we can use IV for nonce explicit according to spec */
 272         buf[3] = pkt_len >> 8;
 273         buf[4] = pkt_len & 0xFF;
 274         memcpy(buf + TLS_NONCE_OFFSET,
 275                ctx->tx.iv + TLS_CIPHER_AES_GCM_128_SALT_SIZE, iv_size);
 276 }
 277
 278 static inline void tls_make_aad(char *buf,
 279                                 size_t size,
 280                                 char *record_sequence,
 281                                 int record_sequence_size,
 282                                 unsigned char record_type)
 283 {
 284         memcpy(buf, record_sequence, record_sequence_size);
 285
 286         buf[8] = record_type;
 287         buf[9] = TLS_1_2_VERSION_MAJOR;
 288         buf[10] = TLS_1_2_VERSION_MINOR;
 289         buf[11] = size >> 8;
 290         buf[12] = size & 0xFF;
 291 }
 292
 293 static inline struct tls_context *tls_get_ctx(const struct sock *sk)
 294 {
 295         struct inet_connection_sock *icsk = inet_csk(sk);
 296
 297         return icsk->icsk_ulp_data;
 298 }
 299
 300 static inline struct tls_sw_context *tls_sw_ctx(
 301                 const struct tls_context *tls_ctx)
 302 {
 303         return (struct tls_sw_context *)tls_ctx->priv_ctx;
 304 }
 305
 306 static inline struct tls_offload_context *tls_offload_ctx(
 307                 const struct tls_context *tls_ctx)
 308 {
 309         return (struct tls_offload_context *)tls_ctx->priv_ctx;
 310 }
 311
 312 int tls_proccess_cmsg(struct sock *sk, struct msghdr *msg,
 313                       unsigned char *record_type);
 314 void tls_register_device(struct tls_device *device);
 315 void tls_unregister_device(struct tls_device *device);
 316
 317 #endif /* _TLS_OFFLOAD_H */