/* * Copyright (c) 2016-2017, Mellanox Technologies. All rights reserved. * Copyright (c) 2016-2017, Dave Watson . All rights reserved. * Copyright (c) 2016-2017, Lance Chao . All rights reserved. * Copyright (c) 2016, Fridolin Pokorny . All rights reserved. * Copyright (c) 2016, Nikos Mavrogiannopoulos . All rights reserved. * Copyright (c) 2018, Covalent IO, Inc. http://covalent.io * * 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 #include #include #include #include #include #include #include #include #include "tls.h" struct tls_decrypt_arg { struct_group(inargs, bool zc; bool async; bool async_done; u8 tail; ); struct sk_buff *skb; }; struct tls_decrypt_ctx { struct sock *sk; u8 iv[TLS_MAX_IV_SIZE]; u8 aad[TLS_MAX_AAD_SIZE]; u8 tail; bool free_sgout; struct scatterlist sg[]; }; noinline void tls_err_abort(struct sock *sk, int err) { WARN_ON_ONCE(err >= 0); /* sk->sk_err should contain a positive error code. */ WRITE_ONCE(sk->sk_err, -err); /* Paired with smp_rmb() in tcp_poll() */ smp_wmb(); sk_error_report(sk); } static int __skb_nsg(struct sk_buff *skb, int offset, int len, unsigned int recursion_level) { int start = skb_headlen(skb); int i, chunk = start - offset; struct sk_buff *frag_iter; int elt = 0; if (unlikely(recursion_level >= 24)) return -EMSGSIZE; if (chunk > 0) { if (chunk > len) chunk = len; elt++; len -= chunk; if (len == 0) return elt; offset += chunk; } for (i = 0; i < skb_shinfo(skb)->nr_frags; i++) { int end; WARN_ON(start > offset + len); end = start + skb_frag_size(&skb_shinfo(skb)->frags[i]); chunk = end - offset; if (chunk > 0) { if (chunk > len) chunk = len; elt++; len -= chunk; if (len == 0) return elt; offset += chunk; } start = end; } if (unlikely(skb_has_frag_list(skb))) { skb_walk_frags(skb, frag_iter) { int end, ret; WARN_ON(start > offset + len); end = start + frag_iter->len; chunk = end - offset; if (chunk > 0) { if (chunk > len) chunk = len; ret = __skb_nsg(frag_iter, offset - start, chunk, recursion_level + 1); if (unlikely(ret < 0)) return ret; elt += ret; len -= chunk; if (len == 0) return elt; offset += chunk; } start = end; } } BUG_ON(len); return elt; } /* Return the number of scatterlist elements required to completely map the * skb, or -EMSGSIZE if the recursion depth is exceeded. */ static int skb_nsg(struct sk_buff *skb, int offset, int len) { return __skb_nsg(skb, offset, len, 0); } static int tls_padding_length(struct tls_prot_info *prot, struct sk_buff *skb, struct tls_decrypt_arg *darg) { struct strp_msg *rxm = strp_msg(skb); struct tls_msg *tlm = tls_msg(skb); int sub = 0; /* Determine zero-padding length */ if (prot->version == TLS_1_3_VERSION) { int offset = rxm->full_len - TLS_TAG_SIZE - 1; char content_type = darg->zc ? darg->tail : 0; int err; while (content_type == 0) { if (offset < prot->prepend_size) return -EBADMSG; err = skb_copy_bits(skb, rxm->offset + offset, &content_type, 1); if (err) return err; if (content_type) break; sub++; offset--; } tlm->control = content_type; } return sub; } static void tls_decrypt_done(void *data, int err) { struct aead_request *aead_req = data; struct crypto_aead *aead = crypto_aead_reqtfm(aead_req); struct scatterlist *sgout = aead_req->dst; struct tls_sw_context_rx *ctx; struct tls_decrypt_ctx *dctx; struct tls_context *tls_ctx; struct scatterlist *sg; unsigned int pages; struct sock *sk; int aead_size; /* If requests get too backlogged crypto API returns -EBUSY and calls * ->complete(-EINPROGRESS) immediately followed by ->complete(0) * to make waiting for backlog to flush with crypto_wait_req() easier. * First wait converts -EBUSY -> -EINPROGRESS, and the second one * -EINPROGRESS -> 0. * We have a single struct crypto_async_request per direction, this * scheme doesn't help us, so just ignore the first ->complete(). */ if (err == -EINPROGRESS) return; aead_size = sizeof(*aead_req) + crypto_aead_reqsize(aead); aead_size = ALIGN(aead_size, __alignof__(*dctx)); dctx = (void *)((u8 *)aead_req + aead_size); sk = dctx->sk; tls_ctx = tls_get_ctx(sk); ctx = tls_sw_ctx_rx(tls_ctx); /* Propagate if there was an err */ if (err) { if (err == -EBADMSG) TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR); ctx->async_wait.err = err; tls_err_abort(sk, err); } /* Free the destination pages if skb was not decrypted inplace */ if (dctx->free_sgout) { /* Skip the first S/G entry as it points to AAD */ for_each_sg(sg_next(sgout), sg, UINT_MAX, pages) { if (!sg) break; put_page(sg_page(sg)); } } kfree(aead_req); if (atomic_dec_and_test(&ctx->decrypt_pending)) complete(&ctx->async_wait.completion); } static int tls_decrypt_async_wait(struct tls_sw_context_rx *ctx) { if (!atomic_dec_and_test(&ctx->decrypt_pending)) crypto_wait_req(-EINPROGRESS, &ctx->async_wait); atomic_inc(&ctx->decrypt_pending); return ctx->async_wait.err; } static int tls_do_decryption(struct sock *sk, struct scatterlist *sgin, struct scatterlist *sgout, char *iv_recv, size_t data_len, struct aead_request *aead_req, struct tls_decrypt_arg *darg) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_prot_info *prot = &tls_ctx->prot_info; struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); int ret; aead_request_set_tfm(aead_req, ctx->aead_recv); aead_request_set_ad(aead_req, prot->aad_size); aead_request_set_crypt(aead_req, sgin, sgout, data_len + prot->tag_size, (u8 *)iv_recv); if (darg->async) { aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, tls_decrypt_done, aead_req); DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->decrypt_pending) < 1); atomic_inc(&ctx->decrypt_pending); } else { DECLARE_CRYPTO_WAIT(wait); aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, crypto_req_done, &wait); ret = crypto_aead_decrypt(aead_req); if (ret == -EINPROGRESS || ret == -EBUSY) ret = crypto_wait_req(ret, &wait); return ret; } ret = crypto_aead_decrypt(aead_req); if (ret == -EINPROGRESS) return 0; if (ret == -EBUSY) { ret = tls_decrypt_async_wait(ctx); darg->async_done = true; /* all completions have run, we're not doing async anymore */ darg->async = false; return ret; } atomic_dec(&ctx->decrypt_pending); darg->async = false; return ret; } static void tls_trim_both_msgs(struct sock *sk, int target_size) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_prot_info *prot = &tls_ctx->prot_info; struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec = ctx->open_rec; sk_msg_trim(sk, &rec->msg_plaintext, target_size); if (target_size > 0) target_size += prot->overhead_size; sk_msg_trim(sk, &rec->msg_encrypted, target_size); } static int tls_alloc_encrypted_msg(struct sock *sk, int len) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec = ctx->open_rec; struct sk_msg *msg_en = &rec->msg_encrypted; return sk_msg_alloc(sk, msg_en, len, 0); } static int tls_clone_plaintext_msg(struct sock *sk, int required) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_prot_info *prot = &tls_ctx->prot_info; struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec = ctx->open_rec; struct sk_msg *msg_pl = &rec->msg_plaintext; struct sk_msg *msg_en = &rec->msg_encrypted; int skip, len; /* We add page references worth len bytes from encrypted sg * at the end of plaintext sg. It is guaranteed that msg_en * has enough required room (ensured by caller). */ len = required - msg_pl->sg.size; /* Skip initial bytes in msg_en's data to be able to use * same offset of both plain and encrypted data. */ skip = prot->prepend_size + msg_pl->sg.size; return sk_msg_clone(sk, msg_pl, msg_en, skip, len); } static struct tls_rec *tls_get_rec(struct sock *sk) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_prot_info *prot = &tls_ctx->prot_info; struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct sk_msg *msg_pl, *msg_en; struct tls_rec *rec; int mem_size; mem_size = sizeof(struct tls_rec) + crypto_aead_reqsize(ctx->aead_send); rec = kzalloc(mem_size, sk->sk_allocation); if (!rec) return NULL; msg_pl = &rec->msg_plaintext; msg_en = &rec->msg_encrypted; sk_msg_init(msg_pl); sk_msg_init(msg_en); sg_init_table(rec->sg_aead_in, 2); sg_set_buf(&rec->sg_aead_in[0], rec->aad_space, prot->aad_size); sg_unmark_end(&rec->sg_aead_in[1]); sg_init_table(rec->sg_aead_out, 2); sg_set_buf(&rec->sg_aead_out[0], rec->aad_space, prot->aad_size); sg_unmark_end(&rec->sg_aead_out[1]); rec->sk = sk; return rec; } static void tls_free_rec(struct sock *sk, struct tls_rec *rec) { sk_msg_free(sk, &rec->msg_encrypted); sk_msg_free(sk, &rec->msg_plaintext); kfree(rec); } static void tls_free_open_rec(struct sock *sk) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec = ctx->open_rec; if (rec) { tls_free_rec(sk, rec); ctx->open_rec = NULL; } } int tls_tx_records(struct sock *sk, int flags) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec, *tmp; struct sk_msg *msg_en; int tx_flags, rc = 0; if (tls_is_partially_sent_record(tls_ctx)) { rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); if (flags == -1) tx_flags = rec->tx_flags; else tx_flags = flags; rc = tls_push_partial_record(sk, tls_ctx, tx_flags); if (rc) goto tx_err; /* Full record has been transmitted. * Remove the head of tx_list */ list_del(&rec->list); sk_msg_free(sk, &rec->msg_plaintext); kfree(rec); } /* Tx all ready records */ list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) { if (READ_ONCE(rec->tx_ready)) { if (flags == -1) tx_flags = rec->tx_flags; else tx_flags = flags; msg_en = &rec->msg_encrypted; rc = tls_push_sg(sk, tls_ctx, &msg_en->sg.data[msg_en->sg.curr], 0, tx_flags); if (rc) goto tx_err; list_del(&rec->list); sk_msg_free(sk, &rec->msg_plaintext); kfree(rec); } else { break; } } tx_err: if (rc < 0 && rc != -EAGAIN) tls_err_abort(sk, -EBADMSG); return rc; } static void tls_encrypt_done(void *data, int err) { struct tls_sw_context_tx *ctx; struct tls_context *tls_ctx; struct tls_prot_info *prot; struct tls_rec *rec = data; struct scatterlist *sge; struct sk_msg *msg_en; struct sock *sk; if (err == -EINPROGRESS) /* see the comment in tls_decrypt_done() */ return; msg_en = &rec->msg_encrypted; sk = rec->sk; tls_ctx = tls_get_ctx(sk); prot = &tls_ctx->prot_info; ctx = tls_sw_ctx_tx(tls_ctx); sge = sk_msg_elem(msg_en, msg_en->sg.curr); sge->offset -= prot->prepend_size; sge->length += prot->prepend_size; /* Check if error is previously set on socket */ if (err || sk->sk_err) { rec = NULL; /* If err is already set on socket, return the same code */ if (sk->sk_err) { ctx->async_wait.err = -sk->sk_err; } else { ctx->async_wait.err = err; tls_err_abort(sk, err); } } if (rec) { struct tls_rec *first_rec; /* Mark the record as ready for transmission */ smp_store_mb(rec->tx_ready, true); /* If received record is at head of tx_list, schedule tx */ first_rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); if (rec == first_rec) { /* Schedule the transmission */ if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) schedule_delayed_work(&ctx->tx_work.work, 1); } } if (atomic_dec_and_test(&ctx->encrypt_pending)) complete(&ctx->async_wait.completion); } static int tls_encrypt_async_wait(struct tls_sw_context_tx *ctx) { if (!atomic_dec_and_test(&ctx->encrypt_pending)) crypto_wait_req(-EINPROGRESS, &ctx->async_wait); atomic_inc(&ctx->encrypt_pending); return ctx->async_wait.err; } static int tls_do_encryption(struct sock *sk, struct tls_context *tls_ctx, struct tls_sw_context_tx *ctx, struct aead_request *aead_req, size_t data_len, u32 start) { struct tls_prot_info *prot = &tls_ctx->prot_info; struct tls_rec *rec = ctx->open_rec; struct sk_msg *msg_en = &rec->msg_encrypted; struct scatterlist *sge = sk_msg_elem(msg_en, start); int rc, iv_offset = 0; /* For CCM based ciphers, first byte of IV is a constant */ switch (prot->cipher_type) { case TLS_CIPHER_AES_CCM_128: rec->iv_data[0] = TLS_AES_CCM_IV_B0_BYTE; iv_offset = 1; break; case TLS_CIPHER_SM4_CCM: rec->iv_data[0] = TLS_SM4_CCM_IV_B0_BYTE; iv_offset = 1; break; } memcpy(&rec->iv_data[iv_offset], tls_ctx->tx.iv, prot->iv_size + prot->salt_size); tls_xor_iv_with_seq(prot, rec->iv_data + iv_offset, tls_ctx->tx.rec_seq); sge->offset += prot->prepend_size; sge->length -= prot->prepend_size; msg_en->sg.curr = start; aead_request_set_tfm(aead_req, ctx->aead_send); aead_request_set_ad(aead_req, prot->aad_size); aead_request_set_crypt(aead_req, rec->sg_aead_in, rec->sg_aead_out, data_len, rec->iv_data); aead_request_set_callback(aead_req, CRYPTO_TFM_REQ_MAY_BACKLOG, tls_encrypt_done, rec); /* Add the record in tx_list */ list_add_tail((struct list_head *)&rec->list, &ctx->tx_list); DEBUG_NET_WARN_ON_ONCE(atomic_read(&ctx->encrypt_pending) < 1); atomic_inc(&ctx->encrypt_pending); rc = crypto_aead_encrypt(aead_req); if (rc == -EBUSY) { rc = tls_encrypt_async_wait(ctx); rc = rc ?: -EINPROGRESS; } if (!rc || rc != -EINPROGRESS) { atomic_dec(&ctx->encrypt_pending); sge->offset -= prot->prepend_size; sge->length += prot->prepend_size; } if (!rc) { WRITE_ONCE(rec->tx_ready, true); } else if (rc != -EINPROGRESS) { list_del(&rec->list); return rc; } /* Unhook the record from context if encryption is not failure */ ctx->open_rec = NULL; tls_advance_record_sn(sk, prot, &tls_ctx->tx); return rc; } static int tls_split_open_record(struct sock *sk, struct tls_rec *from, struct tls_rec **to, struct sk_msg *msg_opl, struct sk_msg *msg_oen, u32 split_point, u32 tx_overhead_size, u32 *orig_end) { u32 i, j, bytes = 0, apply = msg_opl->apply_bytes; struct scatterlist *sge, *osge, *nsge; u32 orig_size = msg_opl->sg.size; struct scatterlist tmp = { }; struct sk_msg *msg_npl; struct tls_rec *new; int ret; new = tls_get_rec(sk); if (!new) return -ENOMEM; ret = sk_msg_alloc(sk, &new->msg_encrypted, msg_opl->sg.size + tx_overhead_size, 0); if (ret < 0) { tls_free_rec(sk, new); return ret; } *orig_end = msg_opl->sg.end; i = msg_opl->sg.start; sge = sk_msg_elem(msg_opl, i); while (apply && sge->length) { if (sge->length > apply) { u32 len = sge->length - apply; get_page(sg_page(sge)); sg_set_page(&tmp, sg_page(sge), len, sge->offset + apply); sge->length = apply; bytes += apply; apply = 0; } else { apply -= sge->length; bytes += sge->length; } sk_msg_iter_var_next(i); if (i == msg_opl->sg.end) break; sge = sk_msg_elem(msg_opl, i); } msg_opl->sg.end = i; msg_opl->sg.curr = i; msg_opl->sg.copybreak = 0; msg_opl->apply_bytes = 0; msg_opl->sg.size = bytes; msg_npl = &new->msg_plaintext; msg_npl->apply_bytes = apply; msg_npl->sg.size = orig_size - bytes; j = msg_npl->sg.start; nsge = sk_msg_elem(msg_npl, j); if (tmp.length) { memcpy(nsge, &tmp, sizeof(*nsge)); sk_msg_iter_var_next(j); nsge = sk_msg_elem(msg_npl, j); } osge = sk_msg_elem(msg_opl, i); while (osge->length) { memcpy(nsge, osge, sizeof(*nsge)); sg_unmark_end(nsge); sk_msg_iter_var_next(i); sk_msg_iter_var_next(j); if (i == *orig_end) break; osge = sk_msg_elem(msg_opl, i); nsge = sk_msg_elem(msg_npl, j); } msg_npl->sg.end = j; msg_npl->sg.curr = j; msg_npl->sg.copybreak = 0; *to = new; return 0; } static void tls_merge_open_record(struct sock *sk, struct tls_rec *to, struct tls_rec *from, u32 orig_end) { struct sk_msg *msg_npl = &from->msg_plaintext; struct sk_msg *msg_opl = &to->msg_plaintext; struct scatterlist *osge, *nsge; u32 i, j; i = msg_opl->sg.end; sk_msg_iter_var_prev(i); j = msg_npl->sg.start; osge = sk_msg_elem(msg_opl, i); nsge = sk_msg_elem(msg_npl, j); if (sg_page(osge) == sg_page(nsge) && osge->offset + osge->length == nsge->offset) { osge->length += nsge->length; put_page(sg_page(nsge)); } msg_opl->sg.end = orig_end; msg_opl->sg.curr = orig_end; msg_opl->sg.copybreak = 0; msg_opl->apply_bytes = msg_opl->sg.size + msg_npl->sg.size; msg_opl->sg.size += msg_npl->sg.size; sk_msg_free(sk, &to->msg_encrypted); sk_msg_xfer_full(&to->msg_encrypted, &from->msg_encrypted); kfree(from); } static int tls_push_record(struct sock *sk, int flags, unsigned char record_type) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_prot_info *prot = &tls_ctx->prot_info; struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec = ctx->open_rec, *tmp = NULL; u32 i, split_point, orig_end; struct sk_msg *msg_pl, *msg_en; struct aead_request *req; bool split; int rc; if (!rec) return 0; msg_pl = &rec->msg_plaintext; msg_en = &rec->msg_encrypted; split_point = msg_pl->apply_bytes; split = split_point && split_point < msg_pl->sg.size; if (unlikely((!split && msg_pl->sg.size + prot->overhead_size > msg_en->sg.size) || (split && split_point + prot->overhead_size > msg_en->sg.size))) { split = true; split_point = msg_en->sg.size; } if (split) { rc = tls_split_open_record(sk, rec, &tmp, msg_pl, msg_en, split_point, prot->overhead_size, &orig_end); if (rc < 0) return rc; /* This can happen if above tls_split_open_record allocates * a single large encryption buffer instead of two smaller * ones. In this case adjust pointers and continue without * split. */ if (!msg_pl->sg.size) { tls_merge_open_record(sk, rec, tmp, orig_end); msg_pl = &rec->msg_plaintext; msg_en = &rec->msg_encrypted; split = false; } sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size); } rec->tx_flags = flags; req = &rec->aead_req; i = msg_pl->sg.end; sk_msg_iter_var_prev(i); rec->content_type = record_type; if (prot->version == TLS_1_3_VERSION) { /* Add content type to end of message. No padding added */ sg_set_buf(&rec->sg_content_type, &rec->content_type, 1); sg_mark_end(&rec->sg_content_type); sg_chain(msg_pl->sg.data, msg_pl->sg.end + 1, &rec->sg_content_type); } else { sg_mark_end(sk_msg_elem(msg_pl, i)); } if (msg_pl->sg.end < msg_pl->sg.start) { sg_chain(&msg_pl->sg.data[msg_pl->sg.start], MAX_SKB_FRAGS - msg_pl->sg.start + 1, msg_pl->sg.data); } i = msg_pl->sg.start; sg_chain(rec->sg_aead_in, 2, &msg_pl->sg.data[i]); i = msg_en->sg.end; sk_msg_iter_var_prev(i); sg_mark_end(sk_msg_elem(msg_en, i)); i = msg_en->sg.start; sg_chain(rec->sg_aead_out, 2, &msg_en->sg.data[i]); tls_make_aad(rec->aad_space, msg_pl->sg.size + prot->tail_size, tls_ctx->tx.rec_seq, record_type, prot); tls_fill_prepend(tls_ctx, page_address(sg_page(&msg_en->sg.data[i])) + msg_en->sg.data[i].offset, msg_pl->sg.size + prot->tail_size, record_type); tls_ctx->pending_open_record_frags = false; rc = tls_do_encryption(sk, tls_ctx, ctx, req, msg_pl->sg.size + prot->tail_size, i); if (rc < 0) { if (rc != -EINPROGRESS) { tls_err_abort(sk, -EBADMSG); if (split) { tls_ctx->pending_open_record_frags = true; tls_merge_open_record(sk, rec, tmp, orig_end); } } ctx->async_capable = 1; return rc; } else if (split) { msg_pl = &tmp->msg_plaintext; msg_en = &tmp->msg_encrypted; sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size); tls_ctx->pending_open_record_frags = true; ctx->open_rec = tmp; } return tls_tx_records(sk, flags); } static int bpf_exec_tx_verdict(struct sk_msg *msg, struct sock *sk, bool full_record, u8 record_type, ssize_t *copied, int flags) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct sk_msg msg_redir = { }; struct sk_psock *psock; struct sock *sk_redir; struct tls_rec *rec; bool enospc, policy, redir_ingress; int err = 0, send; u32 delta = 0; policy = !(flags & MSG_SENDPAGE_NOPOLICY); psock = sk_psock_get(sk); if (!psock || !policy) { err = tls_push_record(sk, flags, record_type); if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) { *copied -= sk_msg_free(sk, msg); tls_free_open_rec(sk); err = -sk->sk_err; } if (psock) sk_psock_put(sk, psock); return err; } more_data: enospc = sk_msg_full(msg); if (psock->eval == __SK_NONE) { delta = msg->sg.size; psock->eval = sk_psock_msg_verdict(sk, psock, msg); delta -= msg->sg.size; } if (msg->cork_bytes && msg->cork_bytes > msg->sg.size && !enospc && !full_record) { err = -ENOSPC; goto out_err; } msg->cork_bytes = 0; send = msg->sg.size; if (msg->apply_bytes && msg->apply_bytes < send) send = msg->apply_bytes; switch (psock->eval) { case __SK_PASS: err = tls_push_record(sk, flags, record_type); if (err && err != -EINPROGRESS && sk->sk_err == EBADMSG) { *copied -= sk_msg_free(sk, msg); tls_free_open_rec(sk); err = -sk->sk_err; goto out_err; } break; case __SK_REDIRECT: redir_ingress = psock->redir_ingress; sk_redir = psock->sk_redir; memcpy(&msg_redir, msg, sizeof(*msg)); if (msg->apply_bytes < send) msg->apply_bytes = 0; else msg->apply_bytes -= send; sk_msg_return_zero(sk, msg, send); msg->sg.size -= send; release_sock(sk); err = tcp_bpf_sendmsg_redir(sk_redir, redir_ingress, &msg_redir, send, flags); lock_sock(sk); if (err < 0) { *copied -= sk_msg_free_nocharge(sk, &msg_redir); msg->sg.size = 0; } if (msg->sg.size == 0) tls_free_open_rec(sk); break; case __SK_DROP: default: sk_msg_free_partial(sk, msg, send); if (msg->apply_bytes < send) msg->apply_bytes = 0; else msg->apply_bytes -= send; if (msg->sg.size == 0) tls_free_open_rec(sk); *copied -= (send + delta); err = -EACCES; } if (likely(!err)) { bool reset_eval = !ctx->open_rec; rec = ctx->open_rec; if (rec) { msg = &rec->msg_plaintext; if (!msg->apply_bytes) reset_eval = true; } if (reset_eval) { psock->eval = __SK_NONE; if (psock->sk_redir) { sock_put(psock->sk_redir); psock->sk_redir = NULL; } } if (rec) goto more_data; } out_err: sk_psock_put(sk, psock); return err; } static int tls_sw_push_pending_record(struct sock *sk, int flags) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec = ctx->open_rec; struct sk_msg *msg_pl; size_t copied; if (!rec) return 0; msg_pl = &rec->msg_plaintext; copied = msg_pl->sg.size; if (!copied) return 0; return bpf_exec_tx_verdict(msg_pl, sk, true, TLS_RECORD_TYPE_DATA, &copied, flags); } static int tls_sw_sendmsg_splice(struct sock *sk, struct msghdr *msg, struct sk_msg *msg_pl, size_t try_to_copy, ssize_t *copied) { struct page *page = NULL, **pages = &page; do { ssize_t part; size_t off; part = iov_iter_extract_pages(&msg->msg_iter, &pages, try_to_copy, 1, 0, &off); if (part <= 0) return part ?: -EIO; if (WARN_ON_ONCE(!sendpage_ok(page))) { iov_iter_revert(&msg->msg_iter, part); return -EIO; } sk_msg_page_add(msg_pl, page, part, off); msg_pl->sg.copybreak = 0; msg_pl->sg.curr = msg_pl->sg.end; sk_mem_charge(sk, part); *copied += part; try_to_copy -= part; } while (try_to_copy && !sk_msg_full(msg_pl)); return 0; } static int tls_sw_sendmsg_locked(struct sock *sk, struct msghdr *msg, size_t size) { long timeo = sock_sndtimeo(sk, msg->msg_flags & MSG_DONTWAIT); struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_prot_info *prot = &tls_ctx->prot_info; struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); bool async_capable = ctx->async_capable; unsigned char record_type = TLS_RECORD_TYPE_DATA; bool is_kvec = iov_iter_is_kvec(&msg->msg_iter); bool eor = !(msg->msg_flags & MSG_MORE); size_t try_to_copy; ssize_t copied = 0; struct sk_msg *msg_pl, *msg_en; struct tls_rec *rec; int required_size; int num_async = 0; bool full_record; int record_room; int num_zc = 0; int orig_size; int ret = 0; if (!eor && (msg->msg_flags & MSG_EOR)) return -EINVAL; if (unlikely(msg->msg_controllen)) { ret = tls_process_cmsg(sk, msg, &record_type); if (ret) { if (ret == -EINPROGRESS) num_async++; else if (ret != -EAGAIN) goto send_end; } } while (msg_data_left(msg)) { if (sk->sk_err) { ret = -sk->sk_err; goto send_end; } if (ctx->open_rec) rec = ctx->open_rec; else rec = ctx->open_rec = tls_get_rec(sk); if (!rec) { ret = -ENOMEM; goto send_end; } msg_pl = &rec->msg_plaintext; msg_en = &rec->msg_encrypted; orig_size = msg_pl->sg.size; full_record = false; try_to_copy = msg_data_left(msg); record_room = TLS_MAX_PAYLOAD_SIZE - msg_pl->sg.size; if (try_to_copy >= record_room) { try_to_copy = record_room; full_record = true; } required_size = msg_pl->sg.size + try_to_copy + prot->overhead_size; if (!sk_stream_memory_free(sk)) goto wait_for_sndbuf; alloc_encrypted: ret = tls_alloc_encrypted_msg(sk, required_size); if (ret) { if (ret != -ENOSPC) goto wait_for_memory; /* Adjust try_to_copy according to the amount that was * actually allocated. The difference is due * to max sg elements limit */ try_to_copy -= required_size - msg_en->sg.size; full_record = true; } if (try_to_copy && (msg->msg_flags & MSG_SPLICE_PAGES)) { ret = tls_sw_sendmsg_splice(sk, msg, msg_pl, try_to_copy, &copied); if (ret < 0) goto send_end; tls_ctx->pending_open_record_frags = true; if (sk_msg_full(msg_pl)) full_record = true; if (full_record || eor) goto copied; continue; } if (!is_kvec && (full_record || eor) && !async_capable) { u32 first = msg_pl->sg.end; ret = sk_msg_zerocopy_from_iter(sk, &msg->msg_iter, msg_pl, try_to_copy); if (ret) goto fallback_to_reg_send; num_zc++; copied += try_to_copy; sk_msg_sg_copy_set(msg_pl, first); ret = bpf_exec_tx_verdict(msg_pl, sk, full_record, record_type, &copied, msg->msg_flags); if (ret) { if (ret == -EINPROGRESS) num_async++; else if (ret == -ENOMEM) goto wait_for_memory; else if (ctx->open_rec && ret == -ENOSPC) goto rollback_iter; else if (ret != -EAGAIN) goto send_end; } continue; rollback_iter: copied -= try_to_copy; sk_msg_sg_copy_clear(msg_pl, first); iov_iter_revert(&msg->msg_iter, msg_pl->sg.size - orig_size); fallback_to_reg_send: sk_msg_trim(sk, msg_pl, orig_size); } required_size = msg_pl->sg.size + try_to_copy; ret = tls_clone_plaintext_msg(sk, required_size); if (ret) { if (ret != -ENOSPC) goto send_end; /* Adjust try_to_copy according to the amount that was * actually allocated. The difference is due * to max sg elements limit */ try_to_copy -= required_size - msg_pl->sg.size; full_record = true; sk_msg_trim(sk, msg_en, msg_pl->sg.size + prot->overhead_size); } if (try_to_copy) { ret = sk_msg_memcopy_from_iter(sk, &msg->msg_iter, msg_pl, try_to_copy); if (ret < 0) goto trim_sgl; } /* Open records defined only if successfully copied, otherwise * we would trim the sg but not reset the open record frags. */ tls_ctx->pending_open_record_frags = true; copied += try_to_copy; copied: if (full_record || eor) { ret = bpf_exec_tx_verdict(msg_pl, sk, full_record, record_type, &copied, msg->msg_flags); if (ret) { if (ret == -EINPROGRESS) num_async++; else if (ret == -ENOMEM) goto wait_for_memory; else if (ret != -EAGAIN) { if (ret == -ENOSPC) ret = 0; goto send_end; } } } continue; wait_for_sndbuf: set_bit(SOCK_NOSPACE, &sk->sk_socket->flags); wait_for_memory: ret = sk_stream_wait_memory(sk, &timeo); if (ret) { trim_sgl: if (ctx->open_rec) tls_trim_both_msgs(sk, orig_size); goto send_end; } if (ctx->open_rec && msg_en->sg.size < required_size) goto alloc_encrypted; } if (!num_async) { goto send_end; } else if (num_zc || eor) { int err; /* Wait for pending encryptions to get completed */ err = tls_encrypt_async_wait(ctx); if (err) { ret = err; copied = 0; } } /* Transmit if any encryptions have completed */ if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { cancel_delayed_work(&ctx->tx_work.work); tls_tx_records(sk, msg->msg_flags); } send_end: ret = sk_stream_error(sk, msg->msg_flags, ret); return copied > 0 ? copied : ret; } int tls_sw_sendmsg(struct sock *sk, struct msghdr *msg, size_t size) { struct tls_context *tls_ctx = tls_get_ctx(sk); int ret; if (msg->msg_flags & ~(MSG_MORE | MSG_DONTWAIT | MSG_NOSIGNAL | MSG_CMSG_COMPAT | MSG_SPLICE_PAGES | MSG_EOR | MSG_SENDPAGE_NOPOLICY)) return -EOPNOTSUPP; ret = mutex_lock_interruptible(&tls_ctx->tx_lock); if (ret) return ret; lock_sock(sk); ret = tls_sw_sendmsg_locked(sk, msg, size); release_sock(sk); mutex_unlock(&tls_ctx->tx_lock); return ret; } /* * Handle unexpected EOF during splice without SPLICE_F_MORE set. */ void tls_sw_splice_eof(struct socket *sock) { struct sock *sk = sock->sk; struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec; struct sk_msg *msg_pl; ssize_t copied = 0; bool retrying = false; int ret = 0; if (!ctx->open_rec) return; mutex_lock(&tls_ctx->tx_lock); lock_sock(sk); retry: /* same checks as in tls_sw_push_pending_record() */ rec = ctx->open_rec; if (!rec) goto unlock; msg_pl = &rec->msg_plaintext; if (msg_pl->sg.size == 0) goto unlock; /* Check the BPF advisor and perform transmission. */ ret = bpf_exec_tx_verdict(msg_pl, sk, false, TLS_RECORD_TYPE_DATA, &copied, 0); switch (ret) { case 0: case -EAGAIN: if (retrying) goto unlock; retrying = true; goto retry; case -EINPROGRESS: break; default: goto unlock; } /* Wait for pending encryptions to get completed */ if (tls_encrypt_async_wait(ctx)) goto unlock; /* Transmit if any encryptions have completed */ if (test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { cancel_delayed_work(&ctx->tx_work.work); tls_tx_records(sk, 0); } unlock: release_sock(sk); mutex_unlock(&tls_ctx->tx_lock); } static int tls_rx_rec_wait(struct sock *sk, struct sk_psock *psock, bool nonblock, bool released) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); DEFINE_WAIT_FUNC(wait, woken_wake_function); int ret = 0; long timeo; /* a rekey is pending, let userspace deal with it */ if (unlikely(ctx->key_update_pending)) return -EKEYEXPIRED; timeo = sock_rcvtimeo(sk, nonblock); while (!tls_strp_msg_ready(ctx)) { if (!sk_psock_queue_empty(psock)) return 0; if (sk->sk_err) return sock_error(sk); if (ret < 0) return ret; if (!skb_queue_empty(&sk->sk_receive_queue)) { tls_strp_check_rcv(&ctx->strp); if (tls_strp_msg_ready(ctx)) break; } if (sk->sk_shutdown & RCV_SHUTDOWN) return 0; if (sock_flag(sk, SOCK_DONE)) return 0; if (!timeo) return -EAGAIN; released = true; add_wait_queue(sk_sleep(sk), &wait); sk_set_bit(SOCKWQ_ASYNC_WAITDATA, sk); ret = sk_wait_event(sk, &timeo, tls_strp_msg_ready(ctx) || !sk_psock_queue_empty(psock), &wait); sk_clear_bit(SOCKWQ_ASYNC_WAITDATA, sk); remove_wait_queue(sk_sleep(sk), &wait); /* Handle signals */ if (signal_pending(current)) return sock_intr_errno(timeo); } tls_strp_msg_load(&ctx->strp, released); return 1; } static int tls_setup_from_iter(struct iov_iter *from, int length, int *pages_used, struct scatterlist *to, int to_max_pages) { int rc = 0, i = 0, num_elem = *pages_used, maxpages; struct page *pages[MAX_SKB_FRAGS]; unsigned int size = 0; ssize_t copied, use; size_t offset; while (length > 0) { i = 0; maxpages = to_max_pages - num_elem; if (maxpages == 0) { rc = -EFAULT; goto out; } copied = iov_iter_get_pages2(from, pages, length, maxpages, &offset); if (copied <= 0) { rc = -EFAULT; goto out; } length -= copied; size += copied; while (copied) { use = min_t(int, copied, PAGE_SIZE - offset); sg_set_page(&to[num_elem], pages[i], use, offset); sg_unmark_end(&to[num_elem]); /* We do not uncharge memory from this API */ offset = 0; copied -= use; i++; num_elem++; } } /* Mark the end in the last sg entry if newly added */ if (num_elem > *pages_used) sg_mark_end(&to[num_elem - 1]); out: if (rc) iov_iter_revert(from, size); *pages_used = num_elem; return rc; } static struct sk_buff * tls_alloc_clrtxt_skb(struct sock *sk, struct sk_buff *skb, unsigned int full_len) { struct strp_msg *clr_rxm; struct sk_buff *clr_skb; int err; clr_skb = alloc_skb_with_frags(0, full_len, TLS_PAGE_ORDER, &err, sk->sk_allocation); if (!clr_skb) return NULL; skb_copy_header(clr_skb, skb); clr_skb->len = full_len; clr_skb->data_len = full_len; clr_rxm = strp_msg(clr_skb); clr_rxm->offset = 0; return clr_skb; } /* Decrypt handlers * * tls_decrypt_sw() and tls_decrypt_device() are decrypt handlers. * They must transform the darg in/out argument are as follows: * | Input | Output * ------------------------------------------------------------------- * zc | Zero-copy decrypt allowed | Zero-copy performed * async | Async decrypt allowed | Async crypto used / in progress * skb | * | Output skb * * If ZC decryption was performed darg.skb will point to the input skb. */ /* This function decrypts the input skb into either out_iov or in out_sg * or in skb buffers itself. The input parameter 'darg->zc' indicates if * zero-copy mode needs to be tried or not. With zero-copy mode, either * out_iov or out_sg must be non-NULL. In case both out_iov and out_sg are * NULL, then the decryption happens inside skb buffers itself, i.e. * zero-copy gets disabled and 'darg->zc' is updated. */ static int tls_decrypt_sg(struct sock *sk, struct iov_iter *out_iov, struct scatterlist *out_sg, struct tls_decrypt_arg *darg) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); struct tls_prot_info *prot = &tls_ctx->prot_info; int n_sgin, n_sgout, aead_size, err, pages = 0; struct sk_buff *skb = tls_strp_msg(ctx); const struct strp_msg *rxm = strp_msg(skb); const struct tls_msg *tlm = tls_msg(skb); struct aead_request *aead_req; struct scatterlist *sgin = NULL; struct scatterlist *sgout = NULL; const int data_len = rxm->full_len - prot->overhead_size; int tail_pages = !!prot->tail_size; struct tls_decrypt_ctx *dctx; struct sk_buff *clear_skb; int iv_offset = 0; u8 *mem; n_sgin = skb_nsg(skb, rxm->offset + prot->prepend_size, rxm->full_len - prot->prepend_size); if (n_sgin < 1) return n_sgin ?: -EBADMSG; if (darg->zc && (out_iov || out_sg)) { clear_skb = NULL; if (out_iov) n_sgout = 1 + tail_pages + iov_iter_npages_cap(out_iov, INT_MAX, data_len); else n_sgout = sg_nents(out_sg); } else { darg->zc = false; clear_skb = tls_alloc_clrtxt_skb(sk, skb, rxm->full_len); if (!clear_skb) return -ENOMEM; n_sgout = 1 + skb_shinfo(clear_skb)->nr_frags; } /* Increment to accommodate AAD */ n_sgin = n_sgin + 1; /* Allocate a single block of memory which contains * aead_req || tls_decrypt_ctx. * Both structs are variable length. */ aead_size = sizeof(*aead_req) + crypto_aead_reqsize(ctx->aead_recv); aead_size = ALIGN(aead_size, __alignof__(*dctx)); mem = kmalloc(aead_size + struct_size(dctx, sg, size_add(n_sgin, n_sgout)), sk->sk_allocation); if (!mem) { err = -ENOMEM; goto exit_free_skb; } /* Segment the allocated memory */ aead_req = (struct aead_request *)mem; dctx = (struct tls_decrypt_ctx *)(mem + aead_size); dctx->sk = sk; sgin = &dctx->sg[0]; sgout = &dctx->sg[n_sgin]; /* For CCM based ciphers, first byte of nonce+iv is a constant */ switch (prot->cipher_type) { case TLS_CIPHER_AES_CCM_128: dctx->iv[0] = TLS_AES_CCM_IV_B0_BYTE; iv_offset = 1; break; case TLS_CIPHER_SM4_CCM: dctx->iv[0] = TLS_SM4_CCM_IV_B0_BYTE; iv_offset = 1; break; } /* Prepare IV */ if (prot->version == TLS_1_3_VERSION || prot->cipher_type == TLS_CIPHER_CHACHA20_POLY1305) { memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, prot->iv_size + prot->salt_size); } else { err = skb_copy_bits(skb, rxm->offset + TLS_HEADER_SIZE, &dctx->iv[iv_offset] + prot->salt_size, prot->iv_size); if (err < 0) goto exit_free; memcpy(&dctx->iv[iv_offset], tls_ctx->rx.iv, prot->salt_size); } tls_xor_iv_with_seq(prot, &dctx->iv[iv_offset], tls_ctx->rx.rec_seq); /* Prepare AAD */ tls_make_aad(dctx->aad, rxm->full_len - prot->overhead_size + prot->tail_size, tls_ctx->rx.rec_seq, tlm->control, prot); /* Prepare sgin */ sg_init_table(sgin, n_sgin); sg_set_buf(&sgin[0], dctx->aad, prot->aad_size); err = skb_to_sgvec(skb, &sgin[1], rxm->offset + prot->prepend_size, rxm->full_len - prot->prepend_size); if (err < 0) goto exit_free; if (clear_skb) { sg_init_table(sgout, n_sgout); sg_set_buf(&sgout[0], dctx->aad, prot->aad_size); err = skb_to_sgvec(clear_skb, &sgout[1], prot->prepend_size, data_len + prot->tail_size); if (err < 0) goto exit_free; } else if (out_iov) { sg_init_table(sgout, n_sgout); sg_set_buf(&sgout[0], dctx->aad, prot->aad_size); err = tls_setup_from_iter(out_iov, data_len, &pages, &sgout[1], (n_sgout - 1 - tail_pages)); if (err < 0) goto exit_free_pages; if (prot->tail_size) { sg_unmark_end(&sgout[pages]); sg_set_buf(&sgout[pages + 1], &dctx->tail, prot->tail_size); sg_mark_end(&sgout[pages + 1]); } } else if (out_sg) { memcpy(sgout, out_sg, n_sgout * sizeof(*sgout)); } dctx->free_sgout = !!pages; /* Prepare and submit AEAD request */ err = tls_do_decryption(sk, sgin, sgout, dctx->iv, data_len + prot->tail_size, aead_req, darg); if (err) { if (darg->async_done) goto exit_free_skb; goto exit_free_pages; } darg->skb = clear_skb ?: tls_strp_msg(ctx); clear_skb = NULL; if (unlikely(darg->async)) { err = tls_strp_msg_hold(&ctx->strp, &ctx->async_hold); if (err) __skb_queue_tail(&ctx->async_hold, darg->skb); return err; } if (unlikely(darg->async_done)) return 0; if (prot->tail_size) darg->tail = dctx->tail; exit_free_pages: /* Release the pages in case iov was mapped to pages */ for (; pages > 0; pages--) put_page(sg_page(&sgout[pages])); exit_free: kfree(mem); exit_free_skb: consume_skb(clear_skb); return err; } static int tls_decrypt_sw(struct sock *sk, struct tls_context *tls_ctx, struct msghdr *msg, struct tls_decrypt_arg *darg) { struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); struct tls_prot_info *prot = &tls_ctx->prot_info; struct strp_msg *rxm; int pad, err; err = tls_decrypt_sg(sk, &msg->msg_iter, NULL, darg); if (err < 0) { if (err == -EBADMSG) TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTERROR); return err; } /* keep going even for ->async, the code below is TLS 1.3 */ /* If opportunistic TLS 1.3 ZC failed retry without ZC */ if (unlikely(darg->zc && prot->version == TLS_1_3_VERSION && darg->tail != TLS_RECORD_TYPE_DATA)) { darg->zc = false; if (!darg->tail) TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXNOPADVIOL); TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSDECRYPTRETRY); return tls_decrypt_sw(sk, tls_ctx, msg, darg); } pad = tls_padding_length(prot, darg->skb, darg); if (pad < 0) { if (darg->skb != tls_strp_msg(ctx)) consume_skb(darg->skb); return pad; } rxm = strp_msg(darg->skb); rxm->full_len -= pad; return 0; } static int tls_decrypt_device(struct sock *sk, struct msghdr *msg, struct tls_context *tls_ctx, struct tls_decrypt_arg *darg) { struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); struct tls_prot_info *prot = &tls_ctx->prot_info; struct strp_msg *rxm; int pad, err; if (tls_ctx->rx_conf != TLS_HW) return 0; err = tls_device_decrypted(sk, tls_ctx); if (err <= 0) return err; pad = tls_padding_length(prot, tls_strp_msg(ctx), darg); if (pad < 0) return pad; darg->async = false; darg->skb = tls_strp_msg(ctx); /* ->zc downgrade check, in case TLS 1.3 gets here */ darg->zc &= !(prot->version == TLS_1_3_VERSION && tls_msg(darg->skb)->control != TLS_RECORD_TYPE_DATA); rxm = strp_msg(darg->skb); rxm->full_len -= pad; if (!darg->zc) { /* Non-ZC case needs a real skb */ darg->skb = tls_strp_msg_detach(ctx); if (!darg->skb) return -ENOMEM; } else { unsigned int off, len; /* In ZC case nobody cares about the output skb. * Just copy the data here. Note the skb is not fully trimmed. */ off = rxm->offset + prot->prepend_size; len = rxm->full_len - prot->overhead_size; err = skb_copy_datagram_msg(darg->skb, off, msg, len); if (err) return err; } return 1; } static int tls_check_pending_rekey(struct sock *sk, struct tls_context *ctx, struct sk_buff *skb) { const struct strp_msg *rxm = strp_msg(skb); const struct tls_msg *tlm = tls_msg(skb); char hs_type; int err; if (likely(tlm->control != TLS_RECORD_TYPE_HANDSHAKE)) return 0; if (rxm->full_len < 1) return 0; err = skb_copy_bits(skb, rxm->offset, &hs_type, 1); if (err < 0) { DEBUG_NET_WARN_ON_ONCE(1); return err; } if (hs_type == TLS_HANDSHAKE_KEYUPDATE) { struct tls_sw_context_rx *rx_ctx = ctx->priv_ctx_rx; WRITE_ONCE(rx_ctx->key_update_pending, true); TLS_INC_STATS(sock_net(sk), LINUX_MIB_TLSRXREKEYRECEIVED); } return 0; } static int tls_rx_one_record(struct sock *sk, struct msghdr *msg, struct tls_decrypt_arg *darg) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_prot_info *prot = &tls_ctx->prot_info; struct strp_msg *rxm; int err; err = tls_decrypt_device(sk, msg, tls_ctx, darg); if (!err) err = tls_decrypt_sw(sk, tls_ctx, msg, darg); if (err < 0) return err; rxm = strp_msg(darg->skb); rxm->offset += prot->prepend_size; rxm->full_len -= prot->overhead_size; tls_advance_record_sn(sk, prot, &tls_ctx->rx); return tls_check_pending_rekey(sk, tls_ctx, darg->skb); } int decrypt_skb(struct sock *sk, struct scatterlist *sgout) { struct tls_decrypt_arg darg = { .zc = true, }; return tls_decrypt_sg(sk, NULL, sgout, &darg); } static int tls_record_content_type(struct msghdr *msg, struct tls_msg *tlm, u8 *control) { int err; if (!*control) { *control = tlm->control; if (!*control) return -EBADMSG; err = put_cmsg(msg, SOL_TLS, TLS_GET_RECORD_TYPE, sizeof(*control), control); if (*control != TLS_RECORD_TYPE_DATA) { if (err || msg->msg_flags & MSG_CTRUNC) return -EIO; } } else if (*control != tlm->control) { return 0; } return 1; } static void tls_rx_rec_done(struct tls_sw_context_rx *ctx) { tls_strp_msg_done(&ctx->strp); } /* This function traverses the rx_list in tls receive context to copies the * decrypted records into the buffer provided by caller zero copy is not * true. Further, the records are removed from the rx_list if it is not a peek * case and the record has been consumed completely. */ static int process_rx_list(struct tls_sw_context_rx *ctx, struct msghdr *msg, u8 *control, size_t skip, size_t len, bool is_peek, bool *more) { struct sk_buff *skb = skb_peek(&ctx->rx_list); struct tls_msg *tlm; ssize_t copied = 0; int err; while (skip && skb) { struct strp_msg *rxm = strp_msg(skb); tlm = tls_msg(skb); err = tls_record_content_type(msg, tlm, control); if (err <= 0) goto more; if (skip < rxm->full_len) break; skip = skip - rxm->full_len; skb = skb_peek_next(skb, &ctx->rx_list); } while (len && skb) { struct sk_buff *next_skb; struct strp_msg *rxm = strp_msg(skb); int chunk = min_t(unsigned int, rxm->full_len - skip, len); tlm = tls_msg(skb); err = tls_record_content_type(msg, tlm, control); if (err <= 0) goto more; err = skb_copy_datagram_msg(skb, rxm->offset + skip, msg, chunk); if (err < 0) goto more; len = len - chunk; copied = copied + chunk; /* Consume the data from record if it is non-peek case*/ if (!is_peek) { rxm->offset = rxm->offset + chunk; rxm->full_len = rxm->full_len - chunk; /* Return if there is unconsumed data in the record */ if (rxm->full_len - skip) break; } /* The remaining skip-bytes must lie in 1st record in rx_list. * So from the 2nd record, 'skip' should be 0. */ skip = 0; if (msg) msg->msg_flags |= MSG_EOR; next_skb = skb_peek_next(skb, &ctx->rx_list); if (!is_peek) { __skb_unlink(skb, &ctx->rx_list); consume_skb(skb); } skb = next_skb; } err = 0; out: return copied ? : err; more: if (more) *more = true; goto out; } static bool tls_read_flush_backlog(struct sock *sk, struct tls_prot_info *prot, size_t len_left, size_t decrypted, ssize_t done, size_t *flushed_at) { size_t max_rec; if (len_left <= decrypted) return false; max_rec = prot->overhead_size - prot->tail_size + TLS_MAX_PAYLOAD_SIZE; if (done - *flushed_at < SZ_128K && tcp_inq(sk) > max_rec) return false; *flushed_at = done; return sk_flush_backlog(sk); } static int tls_rx_reader_acquire(struct sock *sk, struct tls_sw_context_rx *ctx, bool nonblock) { long timeo; int ret; timeo = sock_rcvtimeo(sk, nonblock); while (unlikely(ctx->reader_present)) { DEFINE_WAIT_FUNC(wait, woken_wake_function); ctx->reader_contended = 1; add_wait_queue(&ctx->wq, &wait); ret = sk_wait_event(sk, &timeo, !READ_ONCE(ctx->reader_present), &wait); remove_wait_queue(&ctx->wq, &wait); if (timeo <= 0) return -EAGAIN; if (signal_pending(current)) return sock_intr_errno(timeo); if (ret < 0) return ret; } WRITE_ONCE(ctx->reader_present, 1); return 0; } static int tls_rx_reader_lock(struct sock *sk, struct tls_sw_context_rx *ctx, bool nonblock) { int err; lock_sock(sk); err = tls_rx_reader_acquire(sk, ctx, nonblock); if (err) release_sock(sk); return err; } static void tls_rx_reader_release(struct sock *sk, struct tls_sw_context_rx *ctx) { if (unlikely(ctx->reader_contended)) { if (wq_has_sleeper(&ctx->wq)) wake_up(&ctx->wq); else ctx->reader_contended = 0; WARN_ON_ONCE(!ctx->reader_present); } WRITE_ONCE(ctx->reader_present, 0); } static void tls_rx_reader_unlock(struct sock *sk, struct tls_sw_context_rx *ctx) { tls_rx_reader_release(sk, ctx); release_sock(sk); } int tls_sw_recvmsg(struct sock *sk, struct msghdr *msg, size_t len, int flags, int *addr_len) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); struct tls_prot_info *prot = &tls_ctx->prot_info; ssize_t decrypted = 0, async_copy_bytes = 0; struct sk_psock *psock; unsigned char control = 0; size_t flushed_at = 0; struct strp_msg *rxm; struct tls_msg *tlm; ssize_t copied = 0; ssize_t peeked = 0; bool async = false; int target, err; bool is_kvec = iov_iter_is_kvec(&msg->msg_iter); bool is_peek = flags & MSG_PEEK; bool rx_more = false; bool released = true; bool bpf_strp_enabled; bool zc_capable; if (unlikely(flags & MSG_ERRQUEUE)) return sock_recv_errqueue(sk, msg, len, SOL_IP, IP_RECVERR); err = tls_rx_reader_lock(sk, ctx, flags & MSG_DONTWAIT); if (err < 0) return err; psock = sk_psock_get(sk); bpf_strp_enabled = sk_psock_strp_enabled(psock); /* If crypto failed the connection is broken */ err = ctx->async_wait.err; if (err) goto end; /* Process pending decrypted records. It must be non-zero-copy */ err = process_rx_list(ctx, msg, &control, 0, len, is_peek, &rx_more); if (err < 0) goto end; copied = err; if (len <= copied || (copied && control != TLS_RECORD_TYPE_DATA) || rx_more) goto end; target = sock_rcvlowat(sk, flags & MSG_WAITALL, len); len = len - copied; zc_capable = !bpf_strp_enabled && !is_kvec && !is_peek && ctx->zc_capable; decrypted = 0; while (len && (decrypted + copied < target || tls_strp_msg_ready(ctx))) { struct tls_decrypt_arg darg; int to_decrypt, chunk; err = tls_rx_rec_wait(sk, psock, flags & MSG_DONTWAIT, released); if (err <= 0) { if (psock) { chunk = sk_msg_recvmsg(sk, psock, msg, len, flags); if (chunk > 0) { decrypted += chunk; len -= chunk; continue; } } goto recv_end; } memset(&darg.inargs, 0, sizeof(darg.inargs)); rxm = strp_msg(tls_strp_msg(ctx)); tlm = tls_msg(tls_strp_msg(ctx)); to_decrypt = rxm->full_len - prot->overhead_size; if (zc_capable && to_decrypt <= len && tlm->control == TLS_RECORD_TYPE_DATA) darg.zc = true; /* Do not use async mode if record is non-data */ if (tlm->control == TLS_RECORD_TYPE_DATA && !bpf_strp_enabled) darg.async = ctx->async_capable; else darg.async = false; err = tls_rx_one_record(sk, msg, &darg); if (err < 0) { tls_err_abort(sk, -EBADMSG); goto recv_end; } async |= darg.async; /* If the type of records being processed is not known yet, * set it to record type just dequeued. If it is already known, * but does not match the record type just dequeued, go to end. * We always get record type here since for tls1.2, record type * is known just after record is dequeued from stream parser. * For tls1.3, we disable async. */ err = tls_record_content_type(msg, tls_msg(darg.skb), &control); if (err <= 0) { DEBUG_NET_WARN_ON_ONCE(darg.zc); tls_rx_rec_done(ctx); put_on_rx_list_err: __skb_queue_tail(&ctx->rx_list, darg.skb); goto recv_end; } /* periodically flush backlog, and feed strparser */ released = tls_read_flush_backlog(sk, prot, len, to_decrypt, decrypted + copied, &flushed_at); /* TLS 1.3 may have updated the length by more than overhead */ rxm = strp_msg(darg.skb); chunk = rxm->full_len; tls_rx_rec_done(ctx); if (!darg.zc) { bool partially_consumed = chunk > len; struct sk_buff *skb = darg.skb; DEBUG_NET_WARN_ON_ONCE(darg.skb == ctx->strp.anchor); if (async) { /* TLS 1.2-only, to_decrypt must be text len */ chunk = min_t(int, to_decrypt, len); async_copy_bytes += chunk; put_on_rx_list: decrypted += chunk; len -= chunk; __skb_queue_tail(&ctx->rx_list, skb); if (unlikely(control != TLS_RECORD_TYPE_DATA)) break; continue; } if (bpf_strp_enabled) { released = true; err = sk_psock_tls_strp_read(psock, skb); if (err != __SK_PASS) { rxm->offset = rxm->offset + rxm->full_len; rxm->full_len = 0; if (err == __SK_DROP) consume_skb(skb); continue; } } if (partially_consumed) chunk = len; err = skb_copy_datagram_msg(skb, rxm->offset, msg, chunk); if (err < 0) goto put_on_rx_list_err; if (is_peek) { peeked += chunk; goto put_on_rx_list; } if (partially_consumed) { rxm->offset += chunk; rxm->full_len -= chunk; goto put_on_rx_list; } consume_skb(skb); } decrypted += chunk; len -= chunk; /* Return full control message to userspace before trying * to parse another message type */ msg->msg_flags |= MSG_EOR; if (control != TLS_RECORD_TYPE_DATA) break; } recv_end: if (async) { int ret; /* Wait for all previously submitted records to be decrypted */ ret = tls_decrypt_async_wait(ctx); __skb_queue_purge(&ctx->async_hold); if (ret) { if (err >= 0 || err == -EINPROGRESS) err = ret; goto end; } /* Drain records from the rx_list & copy if required */ if (is_peek) err = process_rx_list(ctx, msg, &control, copied + peeked, decrypted - peeked, is_peek, NULL); else err = process_rx_list(ctx, msg, &control, 0, async_copy_bytes, is_peek, NULL); /* we could have copied less than we wanted, and possibly nothing */ decrypted += max(err, 0) - async_copy_bytes; } copied += decrypted; end: tls_rx_reader_unlock(sk, ctx); if (psock) sk_psock_put(sk, psock); return copied ? : err; } ssize_t tls_sw_splice_read(struct socket *sock, loff_t *ppos, struct pipe_inode_info *pipe, size_t len, unsigned int flags) { struct tls_context *tls_ctx = tls_get_ctx(sock->sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); struct strp_msg *rxm = NULL; struct sock *sk = sock->sk; struct tls_msg *tlm; struct sk_buff *skb; ssize_t copied = 0; int chunk; int err; err = tls_rx_reader_lock(sk, ctx, flags & SPLICE_F_NONBLOCK); if (err < 0) return err; if (!skb_queue_empty(&ctx->rx_list)) { skb = __skb_dequeue(&ctx->rx_list); } else { struct tls_decrypt_arg darg; err = tls_rx_rec_wait(sk, NULL, flags & SPLICE_F_NONBLOCK, true); if (err <= 0) goto splice_read_end; memset(&darg.inargs, 0, sizeof(darg.inargs)); err = tls_rx_one_record(sk, NULL, &darg); if (err < 0) { tls_err_abort(sk, -EBADMSG); goto splice_read_end; } tls_rx_rec_done(ctx); skb = darg.skb; } rxm = strp_msg(skb); tlm = tls_msg(skb); /* splice does not support reading control messages */ if (tlm->control != TLS_RECORD_TYPE_DATA) { err = -EINVAL; goto splice_requeue; } chunk = min_t(unsigned int, rxm->full_len, len); copied = skb_splice_bits(skb, sk, rxm->offset, pipe, chunk, flags); if (copied < 0) goto splice_requeue; if (chunk < rxm->full_len) { rxm->offset += len; rxm->full_len -= len; goto splice_requeue; } consume_skb(skb); splice_read_end: tls_rx_reader_unlock(sk, ctx); return copied ? : err; splice_requeue: __skb_queue_head(&ctx->rx_list, skb); goto splice_read_end; } int tls_sw_read_sock(struct sock *sk, read_descriptor_t *desc, sk_read_actor_t read_actor) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); struct tls_prot_info *prot = &tls_ctx->prot_info; struct strp_msg *rxm = NULL; struct sk_buff *skb = NULL; struct sk_psock *psock; size_t flushed_at = 0; bool released = true; struct tls_msg *tlm; ssize_t copied = 0; ssize_t decrypted; int err, used; psock = sk_psock_get(sk); if (psock) { sk_psock_put(sk, psock); return -EINVAL; } err = tls_rx_reader_acquire(sk, ctx, true); if (err < 0) return err; /* If crypto failed the connection is broken */ err = ctx->async_wait.err; if (err) goto read_sock_end; decrypted = 0; do { if (!skb_queue_empty(&ctx->rx_list)) { skb = __skb_dequeue(&ctx->rx_list); rxm = strp_msg(skb); tlm = tls_msg(skb); } else { struct tls_decrypt_arg darg; err = tls_rx_rec_wait(sk, NULL, true, released); if (err <= 0) goto read_sock_end; memset(&darg.inargs, 0, sizeof(darg.inargs)); err = tls_rx_one_record(sk, NULL, &darg); if (err < 0) { tls_err_abort(sk, -EBADMSG); goto read_sock_end; } released = tls_read_flush_backlog(sk, prot, INT_MAX, 0, decrypted, &flushed_at); skb = darg.skb; rxm = strp_msg(skb); tlm = tls_msg(skb); decrypted += rxm->full_len; tls_rx_rec_done(ctx); } /* read_sock does not support reading control messages */ if (tlm->control != TLS_RECORD_TYPE_DATA) { err = -EINVAL; goto read_sock_requeue; } used = read_actor(desc, skb, rxm->offset, rxm->full_len); if (used <= 0) { if (!copied) err = used; goto read_sock_requeue; } copied += used; if (used < rxm->full_len) { rxm->offset += used; rxm->full_len -= used; if (!desc->count) goto read_sock_requeue; } else { consume_skb(skb); if (!desc->count) skb = NULL; } } while (skb); read_sock_end: tls_rx_reader_release(sk, ctx); return copied ? : err; read_sock_requeue: __skb_queue_head(&ctx->rx_list, skb); goto read_sock_end; } bool tls_sw_sock_is_readable(struct sock *sk) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); bool ingress_empty = true; struct sk_psock *psock; rcu_read_lock(); psock = sk_psock(sk); if (psock) ingress_empty = list_empty(&psock->ingress_msg); rcu_read_unlock(); return !ingress_empty || tls_strp_msg_ready(ctx) || !skb_queue_empty(&ctx->rx_list); } int tls_rx_msg_size(struct tls_strparser *strp, struct sk_buff *skb) { struct tls_context *tls_ctx = tls_get_ctx(strp->sk); struct tls_prot_info *prot = &tls_ctx->prot_info; char header[TLS_HEADER_SIZE + TLS_MAX_IV_SIZE]; size_t cipher_overhead; size_t data_len = 0; int ret; /* Verify that we have a full TLS header, or wait for more data */ if (strp->stm.offset + prot->prepend_size > skb->len) return 0; /* Sanity-check size of on-stack buffer. */ if (WARN_ON(prot->prepend_size > sizeof(header))) { ret = -EINVAL; goto read_failure; } /* Linearize header to local buffer */ ret = skb_copy_bits(skb, strp->stm.offset, header, prot->prepend_size); if (ret < 0) goto read_failure; strp->mark = header[0]; data_len = ((header[4] & 0xFF) | (header[3] << 8)); cipher_overhead = prot->tag_size; if (prot->version != TLS_1_3_VERSION && prot->cipher_type != TLS_CIPHER_CHACHA20_POLY1305) cipher_overhead += prot->iv_size; if (data_len > TLS_MAX_PAYLOAD_SIZE + cipher_overhead + prot->tail_size) { ret = -EMSGSIZE; goto read_failure; } if (data_len < cipher_overhead) { ret = -EBADMSG; goto read_failure; } /* Note that both TLS1.3 and TLS1.2 use TLS_1_2 version here */ if (header[1] != TLS_1_2_VERSION_MINOR || header[2] != TLS_1_2_VERSION_MAJOR) { ret = -EINVAL; goto read_failure; } tls_device_rx_resync_new_rec(strp->sk, data_len + TLS_HEADER_SIZE, TCP_SKB_CB(skb)->seq + strp->stm.offset); return data_len + TLS_HEADER_SIZE; read_failure: tls_err_abort(strp->sk, ret); return ret; } void tls_rx_msg_ready(struct tls_strparser *strp) { struct tls_sw_context_rx *ctx; ctx = container_of(strp, struct tls_sw_context_rx, strp); ctx->saved_data_ready(strp->sk); } static void tls_data_ready(struct sock *sk) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); struct sk_psock *psock; gfp_t alloc_save; trace_sk_data_ready(sk); alloc_save = sk->sk_allocation; sk->sk_allocation = GFP_ATOMIC; tls_strp_data_ready(&ctx->strp); sk->sk_allocation = alloc_save; psock = sk_psock_get(sk); if (psock) { if (!list_empty(&psock->ingress_msg)) ctx->saved_data_ready(sk); sk_psock_put(sk, psock); } } void tls_sw_cancel_work_tx(struct tls_context *tls_ctx) { struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); set_bit(BIT_TX_CLOSING, &ctx->tx_bitmask); set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask); cancel_delayed_work_sync(&ctx->tx_work.work); } void tls_sw_release_resources_tx(struct sock *sk) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); struct tls_rec *rec, *tmp; /* Wait for any pending async encryptions to complete */ tls_encrypt_async_wait(ctx); tls_tx_records(sk, -1); /* Free up un-sent records in tx_list. First, free * the partially sent record if any at head of tx_list. */ if (tls_ctx->partially_sent_record) { tls_free_partial_record(sk, tls_ctx); rec = list_first_entry(&ctx->tx_list, struct tls_rec, list); list_del(&rec->list); sk_msg_free(sk, &rec->msg_plaintext); kfree(rec); } list_for_each_entry_safe(rec, tmp, &ctx->tx_list, list) { list_del(&rec->list); sk_msg_free(sk, &rec->msg_encrypted); sk_msg_free(sk, &rec->msg_plaintext); kfree(rec); } crypto_free_aead(ctx->aead_send); tls_free_open_rec(sk); } void tls_sw_free_ctx_tx(struct tls_context *tls_ctx) { struct tls_sw_context_tx *ctx = tls_sw_ctx_tx(tls_ctx); kfree(ctx); } void tls_sw_release_resources_rx(struct sock *sk) { struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); if (ctx->aead_recv) { __skb_queue_purge(&ctx->rx_list); crypto_free_aead(ctx->aead_recv); tls_strp_stop(&ctx->strp); /* If tls_sw_strparser_arm() was not called (cleanup paths) * we still want to tls_strp_stop(), but sk->sk_data_ready was * never swapped. */ if (ctx->saved_data_ready) { write_lock_bh(&sk->sk_callback_lock); sk->sk_data_ready = ctx->saved_data_ready; write_unlock_bh(&sk->sk_callback_lock); } } } void tls_sw_strparser_done(struct tls_context *tls_ctx) { struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); tls_strp_done(&ctx->strp); } void tls_sw_free_ctx_rx(struct tls_context *tls_ctx) { struct tls_sw_context_rx *ctx = tls_sw_ctx_rx(tls_ctx); kfree(ctx); } void tls_sw_free_resources_rx(struct sock *sk) { struct tls_context *tls_ctx = tls_get_ctx(sk); tls_sw_release_resources_rx(sk); tls_sw_free_ctx_rx(tls_ctx); } /* The work handler to transmitt the encrypted records in tx_list */ static void tx_work_handler(struct work_struct *work) { struct delayed_work *delayed_work = to_delayed_work(work); struct tx_work *tx_work = container_of(delayed_work, struct tx_work, work); struct sock *sk = tx_work->sk; struct tls_context *tls_ctx = tls_get_ctx(sk); struct tls_sw_context_tx *ctx; if (unlikely(!tls_ctx)) return; ctx = tls_sw_ctx_tx(tls_ctx); if (test_bit(BIT_TX_CLOSING, &ctx->tx_bitmask)) return; if (!test_and_clear_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) return; if (mutex_trylock(&tls_ctx->tx_lock)) { lock_sock(sk); tls_tx_records(sk, -1); release_sock(sk); mutex_unlock(&tls_ctx->tx_lock); } else if (!test_and_set_bit(BIT_TX_SCHEDULED, &ctx->tx_bitmask)) { /* Someone is holding the tx_lock, they will likely run Tx * and cancel the work on their way out of the lock section. * Schedule a long delay just in case. */ schedule_delayed_work(&ctx->tx_work.work, msecs_to_jiffies(10)); } } static bool tls_is_tx_ready(struct tls_sw_context_tx *ctx) { struct tls_rec *rec; rec = list_first_entry_or_null(&ctx->tx_list, struct tls_rec, list); if (!rec) return false; return READ_ONCE(rec->tx_ready); } void tls_sw_write_space(struct sock *sk, struct tls_context *ctx) { struct tls_sw_context_tx *tx_ctx = tls_sw_ctx_tx(ctx); /* Schedule the transmission if tx list is ready */ if (tls_is_tx_ready(tx_ctx) && !test_and_set_bit(BIT_TX_SCHEDULED, &tx_ctx->tx_bitmask)) schedule_delayed_work(&tx_ctx->tx_work.work, 0); } void tls_sw_strparser_arm(struct sock *sk, struct tls_context *tls_ctx) { struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx); write_lock_bh(&sk->sk_callback_lock); rx_ctx->saved_data_ready = sk->sk_data_ready; sk->sk_data_ready = tls_data_ready; write_unlock_bh(&sk->sk_callback_lock); } void tls_update_rx_zc_capable(struct tls_context *tls_ctx) { struct tls_sw_context_rx *rx_ctx = tls_sw_ctx_rx(tls_ctx); rx_ctx->zc_capable = tls_ctx->rx_no_pad || tls_ctx->prot_info.version != TLS_1_3_VERSION; } static struct tls_sw_context_tx *init_ctx_tx(struct tls_context *ctx, struct sock *sk) { struct tls_sw_context_tx *sw_ctx_tx; if (!ctx->priv_ctx_tx) { sw_ctx_tx = kzalloc(sizeof(*sw_ctx_tx), GFP_KERNEL); if (!sw_ctx_tx) return NULL; } else { sw_ctx_tx = ctx->priv_ctx_tx; } crypto_init_wait(&sw_ctx_tx->async_wait); atomic_set(&sw_ctx_tx->encrypt_pending, 1); INIT_LIST_HEAD(&sw_ctx_tx->tx_list); INIT_DELAYED_WORK(&sw_ctx_tx->tx_work.work, tx_work_handler); sw_ctx_tx->tx_work.sk = sk; return sw_ctx_tx; } static struct tls_sw_context_rx *init_ctx_rx(struct tls_context *ctx) { struct tls_sw_context_rx *sw_ctx_rx; if (!ctx->priv_ctx_rx) { sw_ctx_rx = kzalloc(sizeof(*sw_ctx_rx), GFP_KERNEL); if (!sw_ctx_rx) return NULL; } else { sw_ctx_rx = ctx->priv_ctx_rx; } crypto_init_wait(&sw_ctx_rx->async_wait); atomic_set(&sw_ctx_rx->decrypt_pending, 1); init_waitqueue_head(&sw_ctx_rx->wq); skb_queue_head_init(&sw_ctx_rx->rx_list); skb_queue_head_init(&sw_ctx_rx->async_hold); return sw_ctx_rx; } int init_prot_info(struct tls_prot_info *prot, const struct tls_crypto_info *crypto_info, const struct tls_cipher_desc *cipher_desc) { u16 nonce_size = cipher_desc->nonce; if (crypto_info->version == TLS_1_3_VERSION) { nonce_size = 0; prot->aad_size = TLS_HEADER_SIZE; prot->tail_size = 1; } else { prot->aad_size = TLS_AAD_SPACE_SIZE; prot->tail_size = 0; } /* Sanity-check the sizes for stack allocations. */ if (nonce_size > TLS_MAX_IV_SIZE || prot->aad_size > TLS_MAX_AAD_SIZE) return -EINVAL; prot->version = crypto_info->version; prot->cipher_type = crypto_info->cipher_type; prot->prepend_size = TLS_HEADER_SIZE + nonce_size; prot->tag_size = cipher_desc->tag; prot->overhead_size = prot->prepend_size + prot->tag_size + prot->tail_size; prot->iv_size = cipher_desc->iv; prot->salt_size = cipher_desc->salt; prot->rec_seq_size = cipher_desc->rec_seq; return 0; } static void tls_finish_key_update(struct sock *sk, struct tls_context *tls_ctx) { struct tls_sw_context_rx *ctx = tls_ctx->priv_ctx_rx; WRITE_ONCE(ctx->key_update_pending, false); /* wake-up pre-existing poll() */ ctx->saved_data_ready(sk); } int tls_set_sw_offload(struct sock *sk, int tx, struct tls_crypto_info *new_crypto_info) { struct tls_crypto_info *crypto_info, *src_crypto_info; struct tls_sw_context_tx *sw_ctx_tx = NULL; struct tls_sw_context_rx *sw_ctx_rx = NULL; const struct tls_cipher_desc *cipher_desc; char *iv, *rec_seq, *key, *salt; struct cipher_context *cctx; struct tls_prot_info *prot; struct crypto_aead **aead; struct tls_context *ctx; struct crypto_tfm *tfm; int rc = 0; ctx = tls_get_ctx(sk); prot = &ctx->prot_info; /* new_crypto_info != NULL means rekey */ if (!new_crypto_info) { if (tx) { ctx->priv_ctx_tx = init_ctx_tx(ctx, sk); if (!ctx->priv_ctx_tx) return -ENOMEM; } else { ctx->priv_ctx_rx = init_ctx_rx(ctx); if (!ctx->priv_ctx_rx) return -ENOMEM; } } if (tx) { sw_ctx_tx = ctx->priv_ctx_tx; crypto_info = &ctx->crypto_send.info; cctx = &ctx->tx; aead = &sw_ctx_tx->aead_send; } else { sw_ctx_rx = ctx->priv_ctx_rx; crypto_info = &ctx->crypto_recv.info; cctx = &ctx->rx; aead = &sw_ctx_rx->aead_recv; } src_crypto_info = new_crypto_info ?: crypto_info; cipher_desc = get_cipher_desc(src_crypto_info->cipher_type); if (!cipher_desc) { rc = -EINVAL; goto free_priv; } rc = init_prot_info(prot, src_crypto_info, cipher_desc); if (rc) goto free_priv; iv = crypto_info_iv(src_crypto_info, cipher_desc); key = crypto_info_key(src_crypto_info, cipher_desc); salt = crypto_info_salt(src_crypto_info, cipher_desc); rec_seq = crypto_info_rec_seq(src_crypto_info, cipher_desc); if (!*aead) { *aead = crypto_alloc_aead(cipher_desc->cipher_name, 0, 0); if (IS_ERR(*aead)) { rc = PTR_ERR(*aead); *aead = NULL; goto free_priv; } } ctx->push_pending_record = tls_sw_push_pending_record; /* setkey is the last operation that could fail during a * rekey. if it succeeds, we can start modifying the * context. */ rc = crypto_aead_setkey(*aead, key, cipher_desc->key); if (rc) { if (new_crypto_info) goto out; else goto free_aead; } if (!new_crypto_info) { rc = crypto_aead_setauthsize(*aead, prot->tag_size); if (rc) goto free_aead; } if (!tx && !new_crypto_info) { tfm = crypto_aead_tfm(sw_ctx_rx->aead_recv); tls_update_rx_zc_capable(ctx); sw_ctx_rx->async_capable = src_crypto_info->version != TLS_1_3_VERSION && !!(tfm->__crt_alg->cra_flags & CRYPTO_ALG_ASYNC); rc = tls_strp_init(&sw_ctx_rx->strp, sk); if (rc) goto free_aead; } memcpy(cctx->iv, salt, cipher_desc->salt); memcpy(cctx->iv + cipher_desc->salt, iv, cipher_desc->iv); memcpy(cctx->rec_seq, rec_seq, cipher_desc->rec_seq); if (new_crypto_info) { unsafe_memcpy(crypto_info, new_crypto_info, cipher_desc->crypto_info, /* size was checked in do_tls_setsockopt_conf */); memzero_explicit(new_crypto_info, cipher_desc->crypto_info); if (!tx) tls_finish_key_update(sk, ctx); } goto out; free_aead: crypto_free_aead(*aead); *aead = NULL; free_priv: if (!new_crypto_info) { if (tx) { kfree(ctx->priv_ctx_tx); ctx->priv_ctx_tx = NULL; } else { kfree(ctx->priv_ctx_rx); ctx->priv_ctx_rx = NULL; } } out: return rc; }