diff options
Diffstat (limited to 'net/tls/tls_device.c')
| -rw-r--r-- | net/tls/tls_device.c | 1487 |
1 files changed, 1487 insertions, 0 deletions
diff --git a/net/tls/tls_device.c b/net/tls/tls_device.c new file mode 100644 index 000000000..184982788 --- /dev/null +++ b/net/tls/tls_device.c @@ -0,0 +1,1487 @@ +/* Copyright (c) 2018, Mellanox Technologies All rights reserved. + * + * This software is available to you under a choice of one of two + * licenses. You may choose to be licensed under the terms of the GNU + * General Public License (GPL) Version 2, available from the file + * COPYING in the main directory of this source tree, or the + * OpenIB.org BSD license below: + * + * Redistribution and use in source and binary forms, with or + * without modification, are permitted provided that the following + * conditions are met: + * + * - Redistributions of source code must retain the above + * copyright notice, this list of conditions and the following + * disclaimer. + * + * - Redistributions in binary form must reproduce the above + * copyright notice, this list of conditions and the following + * disclaimer in the documentation and/or other materials + * provided with the distribution. + * + * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, + * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF + * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND + * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS + * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN + * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN + * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE + * SOFTWARE. + */ + +#include <crypto/aead.h> +#include <linux/highmem.h> +#include <linux/module.h> +#include <linux/netdevice.h> +#include <net/dst.h> +#include <net/inet_connection_sock.h> +#include <net/tcp.h> +#include <net/tls.h> + +#include "tls.h" +#include "trace.h" + +/* device_offload_lock is used to synchronize tls_dev_add + * against NETDEV_DOWN notifications. + */ +static DECLARE_RWSEM(device_offload_lock); + +static struct workqueue_struct *destruct_wq __read_mostly; + +static LIST_HEAD(tls_device_list); +static LIST_HEAD(tls_device_down_list); +static DEFINE_SPINLOCK(tls_device_lock); + +static struct page *dummy_page; + +static void tls_device_free_ctx(struct tls_context *ctx) +{ + if (ctx->tx_conf == TLS_HW) { + kfree(tls_offload_ctx_tx(ctx)); + kfree(ctx->tx.rec_seq); + kfree(ctx->tx.iv); + } + + if (ctx->rx_conf == TLS_HW) + kfree(tls_offload_ctx_rx(ctx)); + + tls_ctx_free(NULL, ctx); +} + +static void tls_device_tx_del_task(struct work_struct *work) +{ + struct tls_offload_context_tx *offload_ctx = + container_of(work, struct tls_offload_context_tx, destruct_work); + struct tls_context *ctx = offload_ctx->ctx; + struct net_device *netdev; + + /* Safe, because this is the destroy flow, refcount is 0, so + * tls_device_down can't store this field in parallel. + */ + netdev = rcu_dereference_protected(ctx->netdev, + !refcount_read(&ctx->refcount)); + + netdev->tlsdev_ops->tls_dev_del(netdev, ctx, TLS_OFFLOAD_CTX_DIR_TX); + dev_put(netdev); + ctx->netdev = NULL; + tls_device_free_ctx(ctx); +} + +static void tls_device_queue_ctx_destruction(struct tls_context *ctx) +{ + struct net_device *netdev; + unsigned long flags; + bool async_cleanup; + + spin_lock_irqsave(&tls_device_lock, flags); + if (unlikely(!refcount_dec_and_test(&ctx->refcount))) { + spin_unlock_irqrestore(&tls_device_lock, flags); + return; + } + + list_del(&ctx->list); /* Remove from tls_device_list / tls_device_down_list */ + + /* Safe, because this is the destroy flow, refcount is 0, so + * tls_device_down can't store this field in parallel. + */ + netdev = rcu_dereference_protected(ctx->netdev, + !refcount_read(&ctx->refcount)); + + async_cleanup = netdev && ctx->tx_conf == TLS_HW; + if (async_cleanup) { + struct tls_offload_context_tx *offload_ctx = tls_offload_ctx_tx(ctx); + + /* queue_work inside the spinlock + * to make sure tls_device_down waits for that work. + */ + queue_work(destruct_wq, &offload_ctx->destruct_work); + } + spin_unlock_irqrestore(&tls_device_lock, flags); + + if (!async_cleanup) + tls_device_free_ctx(ctx); +} + +/* We assume that the socket is already connected */ +static struct net_device *get_netdev_for_sock(struct sock *sk) +{ + struct dst_entry *dst = sk_dst_get(sk); + struct net_device *netdev = NULL; + + if (likely(dst)) { + netdev = netdev_sk_get_lowest_dev(dst->dev, sk); + dev_hold(netdev); + } + + dst_release(dst); + + return netdev; +} + +static void destroy_record(struct tls_record_info *record) +{ + int i; + + for (i = 0; i < record->num_frags; i++) + __skb_frag_unref(&record->frags[i], false); + kfree(record); +} + +static void delete_all_records(struct tls_offload_context_tx *offload_ctx) +{ + struct tls_record_info *info, *temp; + + list_for_each_entry_safe(info, temp, &offload_ctx->records_list, list) { + list_del(&info->list); + destroy_record(info); + } + + offload_ctx->retransmit_hint = NULL; +} + +static void tls_icsk_clean_acked(struct sock *sk, u32 acked_seq) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + struct tls_record_info *info, *temp; + struct tls_offload_context_tx *ctx; + u64 deleted_records = 0; + unsigned long flags; + + if (!tls_ctx) + return; + + ctx = tls_offload_ctx_tx(tls_ctx); + + spin_lock_irqsave(&ctx->lock, flags); + info = ctx->retransmit_hint; + if (info && !before(acked_seq, info->end_seq)) + ctx->retransmit_hint = NULL; + + list_for_each_entry_safe(info, temp, &ctx->records_list, list) { + if (before(acked_seq, info->end_seq)) + break; + list_del(&info->list); + + destroy_record(info); + deleted_records++; + } + + ctx->unacked_record_sn += deleted_records; + spin_unlock_irqrestore(&ctx->lock, flags); +} + +/* At this point, there should be no references on this + * socket and no in-flight SKBs associated with this + * socket, so it is safe to free all the resources. + */ +void tls_device_sk_destruct(struct sock *sk) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); + + tls_ctx->sk_destruct(sk); + + if (tls_ctx->tx_conf == TLS_HW) { + if (ctx->open_record) + destroy_record(ctx->open_record); + delete_all_records(ctx); + crypto_free_aead(ctx->aead_send); + clean_acked_data_disable(inet_csk(sk)); + } + + tls_device_queue_ctx_destruction(tls_ctx); +} +EXPORT_SYMBOL_GPL(tls_device_sk_destruct); + +void tls_device_free_resources_tx(struct sock *sk) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + + tls_free_partial_record(sk, tls_ctx); +} + +void tls_offload_tx_resync_request(struct sock *sk, u32 got_seq, u32 exp_seq) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + + trace_tls_device_tx_resync_req(sk, got_seq, exp_seq); + WARN_ON(test_and_set_bit(TLS_TX_SYNC_SCHED, &tls_ctx->flags)); +} +EXPORT_SYMBOL_GPL(tls_offload_tx_resync_request); + +static void tls_device_resync_tx(struct sock *sk, struct tls_context *tls_ctx, + u32 seq) +{ + struct net_device *netdev; + struct sk_buff *skb; + int err = 0; + u8 *rcd_sn; + + skb = tcp_write_queue_tail(sk); + if (skb) + TCP_SKB_CB(skb)->eor = 1; + + rcd_sn = tls_ctx->tx.rec_seq; + + trace_tls_device_tx_resync_send(sk, seq, rcd_sn); + down_read(&device_offload_lock); + netdev = rcu_dereference_protected(tls_ctx->netdev, + lockdep_is_held(&device_offload_lock)); + if (netdev) + err = netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, + rcd_sn, + TLS_OFFLOAD_CTX_DIR_TX); + up_read(&device_offload_lock); + if (err) + return; + + clear_bit_unlock(TLS_TX_SYNC_SCHED, &tls_ctx->flags); +} + +static void tls_append_frag(struct tls_record_info *record, + struct page_frag *pfrag, + int size) +{ + skb_frag_t *frag; + + frag = &record->frags[record->num_frags - 1]; + if (skb_frag_page(frag) == pfrag->page && + skb_frag_off(frag) + skb_frag_size(frag) == pfrag->offset) { + skb_frag_size_add(frag, size); + } else { + ++frag; + __skb_frag_set_page(frag, pfrag->page); + skb_frag_off_set(frag, pfrag->offset); + skb_frag_size_set(frag, size); + ++record->num_frags; + get_page(pfrag->page); + } + + pfrag->offset += size; + record->len += size; +} + +static int tls_push_record(struct sock *sk, + struct tls_context *ctx, + struct tls_offload_context_tx *offload_ctx, + struct tls_record_info *record, + int flags) +{ + struct tls_prot_info *prot = &ctx->prot_info; + struct tcp_sock *tp = tcp_sk(sk); + skb_frag_t *frag; + int i; + + record->end_seq = tp->write_seq + record->len; + list_add_tail_rcu(&record->list, &offload_ctx->records_list); + offload_ctx->open_record = NULL; + + if (test_bit(TLS_TX_SYNC_SCHED, &ctx->flags)) + tls_device_resync_tx(sk, ctx, tp->write_seq); + + tls_advance_record_sn(sk, prot, &ctx->tx); + + for (i = 0; i < record->num_frags; i++) { + frag = &record->frags[i]; + sg_unmark_end(&offload_ctx->sg_tx_data[i]); + sg_set_page(&offload_ctx->sg_tx_data[i], skb_frag_page(frag), + skb_frag_size(frag), skb_frag_off(frag)); + sk_mem_charge(sk, skb_frag_size(frag)); + get_page(skb_frag_page(frag)); + } + sg_mark_end(&offload_ctx->sg_tx_data[record->num_frags - 1]); + + /* all ready, send */ + return tls_push_sg(sk, ctx, offload_ctx->sg_tx_data, 0, flags); +} + +static void tls_device_record_close(struct sock *sk, + struct tls_context *ctx, + struct tls_record_info *record, + struct page_frag *pfrag, + unsigned char record_type) +{ + struct tls_prot_info *prot = &ctx->prot_info; + struct page_frag dummy_tag_frag; + + /* append tag + * device will fill in the tag, we just need to append a placeholder + * use socket memory to improve coalescing (re-using a single buffer + * increases frag count) + * if we can't allocate memory now use the dummy page + */ + if (unlikely(pfrag->size - pfrag->offset < prot->tag_size) && + !skb_page_frag_refill(prot->tag_size, pfrag, sk->sk_allocation)) { + dummy_tag_frag.page = dummy_page; + dummy_tag_frag.offset = 0; + pfrag = &dummy_tag_frag; + } + tls_append_frag(record, pfrag, prot->tag_size); + + /* fill prepend */ + tls_fill_prepend(ctx, skb_frag_address(&record->frags[0]), + record->len - prot->overhead_size, + record_type); +} + +static int tls_create_new_record(struct tls_offload_context_tx *offload_ctx, + struct page_frag *pfrag, + size_t prepend_size) +{ + struct tls_record_info *record; + skb_frag_t *frag; + + record = kmalloc(sizeof(*record), GFP_KERNEL); + if (!record) + return -ENOMEM; + + frag = &record->frags[0]; + __skb_frag_set_page(frag, pfrag->page); + skb_frag_off_set(frag, pfrag->offset); + skb_frag_size_set(frag, prepend_size); + + get_page(pfrag->page); + pfrag->offset += prepend_size; + + record->num_frags = 1; + record->len = prepend_size; + offload_ctx->open_record = record; + return 0; +} + +static int tls_do_allocation(struct sock *sk, + struct tls_offload_context_tx *offload_ctx, + struct page_frag *pfrag, + size_t prepend_size) +{ + int ret; + + if (!offload_ctx->open_record) { + if (unlikely(!skb_page_frag_refill(prepend_size, pfrag, + sk->sk_allocation))) { + READ_ONCE(sk->sk_prot)->enter_memory_pressure(sk); + sk_stream_moderate_sndbuf(sk); + return -ENOMEM; + } + + ret = tls_create_new_record(offload_ctx, pfrag, prepend_size); + if (ret) + return ret; + + if (pfrag->size > pfrag->offset) + return 0; + } + + if (!sk_page_frag_refill(sk, pfrag)) + return -ENOMEM; + + return 0; +} + +static int tls_device_copy_data(void *addr, size_t bytes, struct iov_iter *i) +{ + size_t pre_copy, nocache; + + pre_copy = ~((unsigned long)addr - 1) & (SMP_CACHE_BYTES - 1); + if (pre_copy) { + pre_copy = min(pre_copy, bytes); + if (copy_from_iter(addr, pre_copy, i) != pre_copy) + return -EFAULT; + bytes -= pre_copy; + addr += pre_copy; + } + + nocache = round_down(bytes, SMP_CACHE_BYTES); + if (copy_from_iter_nocache(addr, nocache, i) != nocache) + return -EFAULT; + bytes -= nocache; + addr += nocache; + + if (bytes && copy_from_iter(addr, bytes, i) != bytes) + return -EFAULT; + + return 0; +} + +union tls_iter_offset { + struct iov_iter *msg_iter; + int offset; +}; + +static int tls_push_data(struct sock *sk, + union tls_iter_offset iter_offset, + size_t size, int flags, + unsigned char record_type, + struct page *zc_page) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + struct tls_prot_info *prot = &tls_ctx->prot_info; + struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); + struct tls_record_info *record; + int tls_push_record_flags; + struct page_frag *pfrag; + size_t orig_size = size; + u32 max_open_record_len; + bool more = false; + bool done = false; + int copy, rc = 0; + long timeo; + + if (flags & + ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_SENDPAGE_NOTLAST)) + return -EOPNOTSUPP; + + if (unlikely(sk->sk_err)) + return -sk->sk_err; + + flags |= MSG_SENDPAGE_DECRYPTED; + tls_push_record_flags = flags | MSG_SENDPAGE_NOTLAST; + + timeo = sock_sndtimeo(sk, flags & MSG_DONTWAIT); + if (tls_is_partially_sent_record(tls_ctx)) { + rc = tls_push_partial_record(sk, tls_ctx, flags); + if (rc < 0) + return rc; + } + + pfrag = sk_page_frag(sk); + + /* TLS_HEADER_SIZE is not counted as part of the TLS record, and + * we need to leave room for an authentication tag. + */ + max_open_record_len = TLS_MAX_PAYLOAD_SIZE + + prot->prepend_size; + do { + rc = tls_do_allocation(sk, ctx, pfrag, prot->prepend_size); + if (unlikely(rc)) { + rc = sk_stream_wait_memory(sk, &timeo); + if (!rc) + continue; + + record = ctx->open_record; + if (!record) + break; +handle_error: + if (record_type != TLS_RECORD_TYPE_DATA) { + /* avoid sending partial + * record with type != + * application_data + */ + size = orig_size; + destroy_record(record); + ctx->open_record = NULL; + } else if (record->len > prot->prepend_size) { + goto last_record; + } + + break; + } + + record = ctx->open_record; + + copy = min_t(size_t, size, max_open_record_len - record->len); + if (copy && zc_page) { + struct page_frag zc_pfrag; + + zc_pfrag.page = zc_page; + zc_pfrag.offset = iter_offset.offset; + zc_pfrag.size = copy; + tls_append_frag(record, &zc_pfrag, copy); + + iter_offset.offset += copy; + } else if (copy) { + copy = min_t(size_t, copy, pfrag->size - pfrag->offset); + + rc = tls_device_copy_data(page_address(pfrag->page) + + pfrag->offset, copy, + iter_offset.msg_iter); + if (rc) + goto handle_error; + tls_append_frag(record, pfrag, copy); + } + + size -= copy; + if (!size) { +last_record: + tls_push_record_flags = flags; + if (flags & (MSG_SENDPAGE_NOTLAST | MSG_MORE)) { + more = true; + break; + } + + done = true; + } + + if (done || record->len >= max_open_record_len || + (record->num_frags >= MAX_SKB_FRAGS - 1)) { + tls_device_record_close(sk, tls_ctx, record, + pfrag, record_type); + + rc = tls_push_record(sk, + tls_ctx, + ctx, + record, + tls_push_record_flags); + if (rc < 0) + break; + } + } while (!done); + + tls_ctx->pending_open_record_frags = more; + + if (orig_size - size > 0) + rc = orig_size - size; + + return rc; +} + +int tls_device_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) +{ + unsigned char record_type = TLS_RECORD_TYPE_DATA; + struct tls_context *tls_ctx = tls_get_ctx(sk); + union tls_iter_offset iter; + int rc; + + mutex_lock(&tls_ctx->tx_lock); + lock_sock(sk); + + if (unlikely(msg->msg_controllen)) { + rc = tls_process_cmsg(sk, msg, &record_type); + if (rc) + goto out; + } + + iter.msg_iter = &msg->msg_iter; + rc = tls_push_data(sk, iter, size, msg->msg_flags, record_type, NULL); + +out: + release_sock(sk); + mutex_unlock(&tls_ctx->tx_lock); + return rc; +} + +int tls_device_sendpage(struct sock *sk, struct page *page, + int offset, size_t size, int flags) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + union tls_iter_offset iter_offset; + struct iov_iter msg_iter; + char *kaddr; + struct kvec iov; + int rc; + + if (flags & MSG_SENDPAGE_NOTLAST) + flags |= MSG_MORE; + + mutex_lock(&tls_ctx->tx_lock); + lock_sock(sk); + + if (flags & MSG_OOB) { + rc = -EOPNOTSUPP; + goto out; + } + + if (tls_ctx->zerocopy_sendfile) { + iter_offset.offset = offset; + rc = tls_push_data(sk, iter_offset, size, + flags, TLS_RECORD_TYPE_DATA, page); + goto out; + } + + kaddr = kmap(page); + iov.iov_base = kaddr + offset; + iov.iov_len = size; + iov_iter_kvec(&msg_iter, ITER_SOURCE, &iov, 1, size); + iter_offset.msg_iter = &msg_iter; + rc = tls_push_data(sk, iter_offset, size, flags, TLS_RECORD_TYPE_DATA, + NULL); + kunmap(page); + +out: + release_sock(sk); + mutex_unlock(&tls_ctx->tx_lock); + return rc; +} + +struct tls_record_info *tls_get_record(struct tls_offload_context_tx *context, + u32 seq, u64 *p_record_sn) +{ + u64 record_sn = context->hint_record_sn; + struct tls_record_info *info, *last; + + info = context->retransmit_hint; + if (!info || + before(seq, info->end_seq - info->len)) { + /* if retransmit_hint is irrelevant start + * from the beginning of the list + */ + info = list_first_entry_or_null(&context->records_list, + struct tls_record_info, list); + if (!info) + return NULL; + /* send the start_marker record if seq number is before the + * tls offload start marker sequence number. This record is + * required to handle TCP packets which are before TLS offload + * started. + * And if it's not start marker, look if this seq number + * belongs to the list. + */ + if (likely(!tls_record_is_start_marker(info))) { + /* we have the first record, get the last record to see + * if this seq number belongs to the list. + */ + last = list_last_entry(&context->records_list, + struct tls_record_info, list); + + if (!between(seq, tls_record_start_seq(info), + last->end_seq)) + return NULL; + } + record_sn = context->unacked_record_sn; + } + + /* We just need the _rcu for the READ_ONCE() */ + rcu_read_lock(); + list_for_each_entry_from_rcu(info, &context->records_list, list) { + if (before(seq, info->end_seq)) { + if (!context->retransmit_hint || + after(info->end_seq, + context->retransmit_hint->end_seq)) { + context->hint_record_sn = record_sn; + context->retransmit_hint = info; + } + *p_record_sn = record_sn; + goto exit_rcu_unlock; + } + record_sn++; + } + info = NULL; + +exit_rcu_unlock: + rcu_read_unlock(); + return info; +} +EXPORT_SYMBOL(tls_get_record); + +static int tls_device_push_pending_record(struct sock *sk, int flags) +{ + union tls_iter_offset iter; + struct iov_iter msg_iter; + + iov_iter_kvec(&msg_iter, ITER_SOURCE, NULL, 0, 0); + iter.msg_iter = &msg_iter; + return tls_push_data(sk, iter, 0, flags, TLS_RECORD_TYPE_DATA, NULL); +} + +void tls_device_write_space(struct sock *sk, struct tls_context *ctx) +{ + if (tls_is_partially_sent_record(ctx)) { + gfp_t sk_allocation = sk->sk_allocation; + + WARN_ON_ONCE(sk->sk_write_pending); + + sk->sk_allocation = GFP_ATOMIC; + tls_push_partial_record(sk, ctx, + MSG_DONTWAIT | MSG_NOSIGNAL | + MSG_SENDPAGE_DECRYPTED); + sk->sk_allocation = sk_allocation; + } +} + +static void tls_device_resync_rx(struct tls_context *tls_ctx, + struct sock *sk, u32 seq, u8 *rcd_sn) +{ + struct tls_offload_context_rx *rx_ctx = tls_offload_ctx_rx(tls_ctx); + struct net_device *netdev; + + trace_tls_device_rx_resync_send(sk, seq, rcd_sn, rx_ctx->resync_type); + rcu_read_lock(); + netdev = rcu_dereference(tls_ctx->netdev); + if (netdev) + netdev->tlsdev_ops->tls_dev_resync(netdev, sk, seq, rcd_sn, + TLS_OFFLOAD_CTX_DIR_RX); + rcu_read_unlock(); + TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXDEVICERESYNC); +} + +static bool +tls_device_rx_resync_async(struct tls_offload_resync_async *resync_async, + s64 resync_req, u32 *seq, u16 *rcd_delta) +{ + u32 is_async = resync_req & RESYNC_REQ_ASYNC; + u32 req_seq = resync_req >> 32; + u32 req_end = req_seq + ((resync_req >> 16) & 0xffff); + u16 i; + + *rcd_delta = 0; + + if (is_async) { + /* shouldn't get to wraparound: + * too long in async stage, something bad happened + */ + if (WARN_ON_ONCE(resync_async->rcd_delta == USHRT_MAX)) + return false; + + /* asynchronous stage: log all headers seq such that + * req_seq <= seq <= end_seq, and wait for real resync request + */ + if (before(*seq, req_seq)) + return false; + if (!after(*seq, req_end) && + resync_async->loglen < TLS_DEVICE_RESYNC_ASYNC_LOGMAX) + resync_async->log[resync_async->loglen++] = *seq; + + resync_async->rcd_delta++; + + return false; + } + + /* synchronous stage: check against the logged entries and + * proceed to check the next entries if no match was found + */ + for (i = 0; i < resync_async->loglen; i++) + if (req_seq == resync_async->log[i] && + atomic64_try_cmpxchg(&resync_async->req, &resync_req, 0)) { + *rcd_delta = resync_async->rcd_delta - i; + *seq = req_seq; + resync_async->loglen = 0; + resync_async->rcd_delta = 0; + return true; + } + + resync_async->loglen = 0; + resync_async->rcd_delta = 0; + + if (req_seq == *seq && + atomic64_try_cmpxchg(&resync_async->req, + &resync_req, 0)) + return true; + + return false; +} + +void tls_device_rx_resync_new_rec(struct sock *sk, u32 rcd_len, u32 seq) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + struct tls_offload_context_rx *rx_ctx; + u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; + u32 sock_data, is_req_pending; + struct tls_prot_info *prot; + s64 resync_req; + u16 rcd_delta; + u32 req_seq; + + if (tls_ctx->rx_conf != TLS_HW) + return; + if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) + return; + + prot = &tls_ctx->prot_info; + rx_ctx = tls_offload_ctx_rx(tls_ctx); + memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); + + switch (rx_ctx->resync_type) { + case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ: + resync_req = atomic64_read(&rx_ctx->resync_req); + req_seq = resync_req >> 32; + seq += TLS_HEADER_SIZE - 1; + is_req_pending = resync_req; + + if (likely(!is_req_pending) || req_seq != seq || + !atomic64_try_cmpxchg(&rx_ctx->resync_req, &resync_req, 0)) + return; + break; + case TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT: + if (likely(!rx_ctx->resync_nh_do_now)) + return; + + /* head of next rec is already in, note that the sock_inq will + * include the currently parsed message when called from parser + */ + sock_data = tcp_inq(sk); + if (sock_data > rcd_len) { + trace_tls_device_rx_resync_nh_delay(sk, sock_data, + rcd_len); + return; + } + + rx_ctx->resync_nh_do_now = 0; + seq += rcd_len; + tls_bigint_increment(rcd_sn, prot->rec_seq_size); + break; + case TLS_OFFLOAD_SYNC_TYPE_DRIVER_REQ_ASYNC: + resync_req = atomic64_read(&rx_ctx->resync_async->req); + is_req_pending = resync_req; + if (likely(!is_req_pending)) + return; + + if (!tls_device_rx_resync_async(rx_ctx->resync_async, + resync_req, &seq, &rcd_delta)) + return; + tls_bigint_subtract(rcd_sn, rcd_delta); + break; + } + + tls_device_resync_rx(tls_ctx, sk, seq, rcd_sn); +} + +static void tls_device_core_ctrl_rx_resync(struct tls_context *tls_ctx, + struct tls_offload_context_rx *ctx, + struct sock *sk, struct sk_buff *skb) +{ + struct strp_msg *rxm; + + /* device will request resyncs by itself based on stream scan */ + if (ctx->resync_type != TLS_OFFLOAD_SYNC_TYPE_CORE_NEXT_HINT) + return; + /* already scheduled */ + if (ctx->resync_nh_do_now) + return; + /* seen decrypted fragments since last fully-failed record */ + if (ctx->resync_nh_reset) { + ctx->resync_nh_reset = 0; + ctx->resync_nh.decrypted_failed = 1; + ctx->resync_nh.decrypted_tgt = TLS_DEVICE_RESYNC_NH_START_IVAL; + return; + } + + if (++ctx->resync_nh.decrypted_failed <= ctx->resync_nh.decrypted_tgt) + return; + + /* doing resync, bump the next target in case it fails */ + if (ctx->resync_nh.decrypted_tgt < TLS_DEVICE_RESYNC_NH_MAX_IVAL) + ctx->resync_nh.decrypted_tgt *= 2; + else + ctx->resync_nh.decrypted_tgt += TLS_DEVICE_RESYNC_NH_MAX_IVAL; + + rxm = strp_msg(skb); + + /* head of next rec is already in, parser will sync for us */ + if (tcp_inq(sk) > rxm->full_len) { + trace_tls_device_rx_resync_nh_schedule(sk); + ctx->resync_nh_do_now = 1; + } else { + struct tls_prot_info *prot = &tls_ctx->prot_info; + u8 rcd_sn[TLS_MAX_REC_SEQ_SIZE]; + + memcpy(rcd_sn, tls_ctx->rx.rec_seq, prot->rec_seq_size); + tls_bigint_increment(rcd_sn, prot->rec_seq_size); + + tls_device_resync_rx(tls_ctx, sk, tcp_sk(sk)->copied_seq, + rcd_sn); + } +} + +static int +tls_device_reencrypt(struct sock *sk, struct tls_context *tls_ctx) +{ + struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx); + const struct tls_cipher_size_desc *cipher_sz; + int err, offset, copy, data_len, pos; + struct sk_buff *skb, *skb_iter; + struct scatterlist sg[1]; + struct strp_msg *rxm; + char *orig_buf, *buf; + + switch (tls_ctx->crypto_recv.info.cipher_type) { + case TLS_CIPHER_AES_GCM_128: + case TLS_CIPHER_AES_GCM_256: + break; + default: + return -EINVAL; + } + cipher_sz = &tls_cipher_size_desc[tls_ctx->crypto_recv.info.cipher_type]; + + rxm = strp_msg(tls_strp_msg(sw_ctx)); + orig_buf = kmalloc(rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv, + sk->sk_allocation); + if (!orig_buf) + return -ENOMEM; + buf = orig_buf; + + err = tls_strp_msg_cow(sw_ctx); + if (unlikely(err)) + goto free_buf; + + skb = tls_strp_msg(sw_ctx); + rxm = strp_msg(skb); + offset = rxm->offset; + + sg_init_table(sg, 1); + sg_set_buf(&sg[0], buf, + rxm->full_len + TLS_HEADER_SIZE + cipher_sz->iv); + err = skb_copy_bits(skb, offset, buf, TLS_HEADER_SIZE + cipher_sz->iv); + if (err) + goto free_buf; + + /* We are interested only in the decrypted data not the auth */ + err = decrypt_skb(sk, sg); + if (err != -EBADMSG) + goto free_buf; + else + err = 0; + + data_len = rxm->full_len - cipher_sz->tag; + + if (skb_pagelen(skb) > offset) { + copy = min_t(int, skb_pagelen(skb) - offset, data_len); + + if (skb->decrypted) { + err = skb_store_bits(skb, offset, buf, copy); + if (err) + goto free_buf; + } + + offset += copy; + buf += copy; + } + + pos = skb_pagelen(skb); + skb_walk_frags(skb, skb_iter) { + int frag_pos; + + /* Practically all frags must belong to msg if reencrypt + * is needed with current strparser and coalescing logic, + * but strparser may "get optimized", so let's be safe. + */ + if (pos + skb_iter->len <= offset) + goto done_with_frag; + if (pos >= data_len + rxm->offset) + break; + + frag_pos = offset - pos; + copy = min_t(int, skb_iter->len - frag_pos, + data_len + rxm->offset - offset); + + if (skb_iter->decrypted) { + err = skb_store_bits(skb_iter, frag_pos, buf, copy); + if (err) + goto free_buf; + } + + offset += copy; + buf += copy; +done_with_frag: + pos += skb_iter->len; + } + +free_buf: + kfree(orig_buf); + return err; +} + +int tls_device_decrypted(struct sock *sk, struct tls_context *tls_ctx) +{ + struct tls_offload_context_rx *ctx = tls_offload_ctx_rx(tls_ctx); + struct tls_sw_context_rx *sw_ctx = tls_sw_ctx_rx(tls_ctx); + struct sk_buff *skb = tls_strp_msg(sw_ctx); + struct strp_msg *rxm = strp_msg(skb); + int is_decrypted, is_encrypted; + + if (!tls_strp_msg_mixed_decrypted(sw_ctx)) { + is_decrypted = skb->decrypted; + is_encrypted = !is_decrypted; + } else { + is_decrypted = 0; + is_encrypted = 0; + } + + trace_tls_device_decrypted(sk, tcp_sk(sk)->copied_seq - rxm->full_len, + tls_ctx->rx.rec_seq, rxm->full_len, + is_encrypted, is_decrypted); + + if (unlikely(test_bit(TLS_RX_DEV_DEGRADED, &tls_ctx->flags))) { + if (likely(is_encrypted || is_decrypted)) + return is_decrypted; + + /* After tls_device_down disables the offload, the next SKB will + * likely have initial fragments decrypted, and final ones not + * decrypted. We need to reencrypt that single SKB. + */ + return tls_device_reencrypt(sk, tls_ctx); + } + + /* Return immediately if the record is either entirely plaintext or + * entirely ciphertext. Otherwise handle reencrypt partially decrypted + * record. + */ + if (is_decrypted) { + ctx->resync_nh_reset = 1; + return is_decrypted; + } + if (is_encrypted) { + tls_device_core_ctrl_rx_resync(tls_ctx, ctx, sk, skb); + return 0; + } + + ctx->resync_nh_reset = 1; + return tls_device_reencrypt(sk, tls_ctx); +} + +static void tls_device_attach(struct tls_context *ctx, struct sock *sk, + struct net_device *netdev) +{ + if (sk->sk_destruct != tls_device_sk_destruct) { + refcount_set(&ctx->refcount, 1); + dev_hold(netdev); + RCU_INIT_POINTER(ctx->netdev, netdev); + spin_lock_irq(&tls_device_lock); + list_add_tail(&ctx->list, &tls_device_list); + spin_unlock_irq(&tls_device_lock); + + ctx->sk_destruct = sk->sk_destruct; + smp_store_release(&sk->sk_destruct, tls_device_sk_destruct); + } +} + +int tls_set_device_offload(struct sock *sk, struct tls_context *ctx) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + struct tls_prot_info *prot = &tls_ctx->prot_info; + const struct tls_cipher_size_desc *cipher_sz; + struct tls_record_info *start_marker_record; + struct tls_offload_context_tx *offload_ctx; + struct tls_crypto_info *crypto_info; + struct net_device *netdev; + char *iv, *rec_seq; + struct sk_buff *skb; + __be64 rcd_sn; + int rc; + + if (!ctx) + return -EINVAL; + + if (ctx->priv_ctx_tx) + return -EEXIST; + + netdev = get_netdev_for_sock(sk); + if (!netdev) { + pr_err_ratelimited("%s: netdev not found\n", __func__); + return -EINVAL; + } + + if (!(netdev->features & NETIF_F_HW_TLS_TX)) { + rc = -EOPNOTSUPP; + goto release_netdev; + } + + crypto_info = &ctx->crypto_send.info; + if (crypto_info->version != TLS_1_2_VERSION) { + rc = -EOPNOTSUPP; + goto release_netdev; + } + + switch (crypto_info->cipher_type) { + case TLS_CIPHER_AES_GCM_128: + iv = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->iv; + rec_seq = + ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->rec_seq; + break; + case TLS_CIPHER_AES_GCM_256: + iv = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->iv; + rec_seq = + ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->rec_seq; + break; + default: + rc = -EINVAL; + goto release_netdev; + } + cipher_sz = &tls_cipher_size_desc[crypto_info->cipher_type]; + + /* Sanity-check the rec_seq_size for stack allocations */ + if (cipher_sz->rec_seq > TLS_MAX_REC_SEQ_SIZE) { + rc = -EINVAL; + goto release_netdev; + } + + prot->version = crypto_info->version; + prot->cipher_type = crypto_info->cipher_type; + prot->prepend_size = TLS_HEADER_SIZE + cipher_sz->iv; + prot->tag_size = cipher_sz->tag; + prot->overhead_size = prot->prepend_size + prot->tag_size; + prot->iv_size = cipher_sz->iv; + prot->salt_size = cipher_sz->salt; + ctx->tx.iv = kmalloc(cipher_sz->iv + cipher_sz->salt, GFP_KERNEL); + if (!ctx->tx.iv) { + rc = -ENOMEM; + goto release_netdev; + } + + memcpy(ctx->tx.iv + cipher_sz->salt, iv, cipher_sz->iv); + + prot->rec_seq_size = cipher_sz->rec_seq; + ctx->tx.rec_seq = kmemdup(rec_seq, cipher_sz->rec_seq, GFP_KERNEL); + if (!ctx->tx.rec_seq) { + rc = -ENOMEM; + goto free_iv; + } + + start_marker_record = kmalloc(sizeof(*start_marker_record), GFP_KERNEL); + if (!start_marker_record) { + rc = -ENOMEM; + goto free_rec_seq; + } + + offload_ctx = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_TX, GFP_KERNEL); + if (!offload_ctx) { + rc = -ENOMEM; + goto free_marker_record; + } + + rc = tls_sw_fallback_init(sk, offload_ctx, crypto_info); + if (rc) + goto free_offload_ctx; + + /* start at rec_seq - 1 to account for the start marker record */ + memcpy(&rcd_sn, ctx->tx.rec_seq, sizeof(rcd_sn)); + offload_ctx->unacked_record_sn = be64_to_cpu(rcd_sn) - 1; + + start_marker_record->end_seq = tcp_sk(sk)->write_seq; + start_marker_record->len = 0; + start_marker_record->num_frags = 0; + + INIT_WORK(&offload_ctx->destruct_work, tls_device_tx_del_task); + offload_ctx->ctx = ctx; + + INIT_LIST_HEAD(&offload_ctx->records_list); + list_add_tail(&start_marker_record->list, &offload_ctx->records_list); + spin_lock_init(&offload_ctx->lock); + sg_init_table(offload_ctx->sg_tx_data, + ARRAY_SIZE(offload_ctx->sg_tx_data)); + + clean_acked_data_enable(inet_csk(sk), &tls_icsk_clean_acked); + ctx->push_pending_record = tls_device_push_pending_record; + + /* TLS offload is greatly simplified if we don't send + * SKBs where only part of the payload needs to be encrypted. + * So mark the last skb in the write queue as end of record. + */ + skb = tcp_write_queue_tail(sk); + if (skb) + TCP_SKB_CB(skb)->eor = 1; + + /* Avoid offloading if the device is down + * We don't want to offload new flows after + * the NETDEV_DOWN event + * + * device_offload_lock is taken in tls_devices's NETDEV_DOWN + * handler thus protecting from the device going down before + * ctx was added to tls_device_list. + */ + down_read(&device_offload_lock); + if (!(netdev->flags & IFF_UP)) { + rc = -EINVAL; + goto release_lock; + } + + ctx->priv_ctx_tx = offload_ctx; + rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_TX, + &ctx->crypto_send.info, + tcp_sk(sk)->write_seq); + trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_TX, + tcp_sk(sk)->write_seq, rec_seq, rc); + if (rc) + goto release_lock; + + tls_device_attach(ctx, sk, netdev); + up_read(&device_offload_lock); + + /* following this assignment tls_is_sk_tx_device_offloaded + * will return true and the context might be accessed + * by the netdev's xmit function. + */ + smp_store_release(&sk->sk_validate_xmit_skb, tls_validate_xmit_skb); + dev_put(netdev); + + return 0; + +release_lock: + up_read(&device_offload_lock); + clean_acked_data_disable(inet_csk(sk)); + crypto_free_aead(offload_ctx->aead_send); +free_offload_ctx: + kfree(offload_ctx); + ctx->priv_ctx_tx = NULL; +free_marker_record: + kfree(start_marker_record); +free_rec_seq: + kfree(ctx->tx.rec_seq); +free_iv: + kfree(ctx->tx.iv); +release_netdev: + dev_put(netdev); + return rc; +} + +int tls_set_device_offload_rx(struct sock *sk, struct tls_context *ctx) +{ + struct tls12_crypto_info_aes_gcm_128 *info; + struct tls_offload_context_rx *context; + struct net_device *netdev; + int rc = 0; + + if (ctx->crypto_recv.info.version != TLS_1_2_VERSION) + return -EOPNOTSUPP; + + netdev = get_netdev_for_sock(sk); + if (!netdev) { + pr_err_ratelimited("%s: netdev not found\n", __func__); + return -EINVAL; + } + + if (!(netdev->features & NETIF_F_HW_TLS_RX)) { + rc = -EOPNOTSUPP; + goto release_netdev; + } + + /* Avoid offloading if the device is down + * We don't want to offload new flows after + * the NETDEV_DOWN event + * + * device_offload_lock is taken in tls_devices's NETDEV_DOWN + * handler thus protecting from the device going down before + * ctx was added to tls_device_list. + */ + down_read(&device_offload_lock); + if (!(netdev->flags & IFF_UP)) { + rc = -EINVAL; + goto release_lock; + } + + context = kzalloc(TLS_OFFLOAD_CONTEXT_SIZE_RX, GFP_KERNEL); + if (!context) { + rc = -ENOMEM; + goto release_lock; + } + context->resync_nh_reset = 1; + + ctx->priv_ctx_rx = context; + rc = tls_set_sw_offload(sk, ctx, 0); + if (rc) + goto release_ctx; + + rc = netdev->tlsdev_ops->tls_dev_add(netdev, sk, TLS_OFFLOAD_CTX_DIR_RX, + &ctx->crypto_recv.info, + tcp_sk(sk)->copied_seq); + info = (void *)&ctx->crypto_recv.info; + trace_tls_device_offload_set(sk, TLS_OFFLOAD_CTX_DIR_RX, + tcp_sk(sk)->copied_seq, info->rec_seq, rc); + if (rc) + goto free_sw_resources; + + tls_device_attach(ctx, sk, netdev); + up_read(&device_offload_lock); + + dev_put(netdev); + + return 0; + +free_sw_resources: + up_read(&device_offload_lock); + tls_sw_free_resources_rx(sk); + down_read(&device_offload_lock); +release_ctx: + ctx->priv_ctx_rx = NULL; +release_lock: + up_read(&device_offload_lock); +release_netdev: + dev_put(netdev); + return rc; +} + +void tls_device_offload_cleanup_rx(struct sock *sk) +{ + struct tls_context *tls_ctx = tls_get_ctx(sk); + struct net_device *netdev; + + down_read(&device_offload_lock); + netdev = rcu_dereference_protected(tls_ctx->netdev, + lockdep_is_held(&device_offload_lock)); + if (!netdev) + goto out; + + netdev->tlsdev_ops->tls_dev_del(netdev, tls_ctx, + TLS_OFFLOAD_CTX_DIR_RX); + + if (tls_ctx->tx_conf != TLS_HW) { + dev_put(netdev); + rcu_assign_pointer(tls_ctx->netdev, NULL); + } else { + set_bit(TLS_RX_DEV_CLOSED, &tls_ctx->flags); + } +out: + up_read(&device_offload_lock); + tls_sw_release_resources_rx(sk); +} + +static int tls_device_down(struct net_device *netdev) +{ + struct tls_context *ctx, *tmp; + unsigned long flags; + LIST_HEAD(list); + + /* Request a write lock to block new offload attempts */ + down_write(&device_offload_lock); + + spin_lock_irqsave(&tls_device_lock, flags); + list_for_each_entry_safe(ctx, tmp, &tls_device_list, list) { + struct net_device *ctx_netdev = + rcu_dereference_protected(ctx->netdev, + lockdep_is_held(&device_offload_lock)); + + if (ctx_netdev != netdev || + !refcount_inc_not_zero(&ctx->refcount)) + continue; + + list_move(&ctx->list, &list); + } + spin_unlock_irqrestore(&tls_device_lock, flags); + + list_for_each_entry_safe(ctx, tmp, &list, list) { + /* Stop offloaded TX and switch to the fallback. + * tls_is_sk_tx_device_offloaded will return false. + */ + WRITE_ONCE(ctx->sk->sk_validate_xmit_skb, tls_validate_xmit_skb_sw); + + /* Stop the RX and TX resync. + * tls_dev_resync must not be called after tls_dev_del. + */ + rcu_assign_pointer(ctx->netdev, NULL); + + /* Start skipping the RX resync logic completely. */ + set_bit(TLS_RX_DEV_DEGRADED, &ctx->flags); + + /* Sync with inflight packets. After this point: + * TX: no non-encrypted packets will be passed to the driver. + * RX: resync requests from the driver will be ignored. + */ + synchronize_net(); + + /* Release the offload context on the driver side. */ + if (ctx->tx_conf == TLS_HW) + netdev->tlsdev_ops->tls_dev_del(netdev, ctx, + TLS_OFFLOAD_CTX_DIR_TX); + if (ctx->rx_conf == TLS_HW && + !test_bit(TLS_RX_DEV_CLOSED, &ctx->flags)) + netdev->tlsdev_ops->tls_dev_del(netdev, ctx, + TLS_OFFLOAD_CTX_DIR_RX); + + dev_put(netdev); + + /* Move the context to a separate list for two reasons: + * 1. When the context is deallocated, list_del is called. + * 2. It's no longer an offloaded context, so we don't want to + * run offload-specific code on this context. + */ + spin_lock_irqsave(&tls_device_lock, flags); + list_move_tail(&ctx->list, &tls_device_down_list); + spin_unlock_irqrestore(&tls_device_lock, flags); + + /* Device contexts for RX and TX will be freed in on sk_destruct + * by tls_device_free_ctx. rx_conf and tx_conf stay in TLS_HW. + * Now release the ref taken above. + */ + if (refcount_dec_and_test(&ctx->refcount)) { + /* sk_destruct ran after tls_device_down took a ref, and + * it returned early. Complete the destruction here. + */ + list_del(&ctx->list); + tls_device_free_ctx(ctx); + } + } + + up_write(&device_offload_lock); + + flush_workqueue(destruct_wq); + + return NOTIFY_DONE; +} + +static int tls_dev_event(struct notifier_block *this, unsigned long event, + void *ptr) +{ + struct net_device *dev = netdev_notifier_info_to_dev(ptr); + + if (!dev->tlsdev_ops && + !(dev->features & (NETIF_F_HW_TLS_RX | NETIF_F_HW_TLS_TX))) + return NOTIFY_DONE; + + switch (event) { + case NETDEV_REGISTER: + case NETDEV_FEAT_CHANGE: + if (netif_is_bond_master(dev)) + return NOTIFY_DONE; + if ((dev->features & NETIF_F_HW_TLS_RX) && + !dev->tlsdev_ops->tls_dev_resync) + return NOTIFY_BAD; + + if (dev->tlsdev_ops && + dev->tlsdev_ops->tls_dev_add && + dev->tlsdev_ops->tls_dev_del) + return NOTIFY_DONE; + else + return NOTIFY_BAD; + case NETDEV_DOWN: + return tls_device_down(dev); + } + return NOTIFY_DONE; +} + +static struct notifier_block tls_dev_notifier = { + .notifier_call = tls_dev_event, +}; + +int __init tls_device_init(void) +{ + int err; + + dummy_page = alloc_page(GFP_KERNEL); + if (!dummy_page) + return -ENOMEM; + + destruct_wq = alloc_workqueue("ktls_device_destruct", 0, 0); + if (!destruct_wq) { + err = -ENOMEM; + goto err_free_dummy; + } + + err = register_netdevice_notifier(&tls_dev_notifier); + if (err) + goto err_destroy_wq; + + return 0; + +err_destroy_wq: + destroy_workqueue(destruct_wq); +err_free_dummy: + put_page(dummy_page); + return err; +} + +void __exit tls_device_cleanup(void) +{ + unregister_netdevice_notifier(&tls_dev_notifier); + destroy_workqueue(destruct_wq); + clean_acked_data_flush(); + put_page(dummy_page); +} |