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author | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
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committer | Daniel Baumann <daniel.baumann@progress-linux.org> | 2024-04-07 18:49:45 +0000 |
commit | 2c3c1048746a4622d8c89a29670120dc8fab93c4 (patch) | |
tree | 848558de17fb3008cdf4d861b01ac7781903ce39 /net/tls/tls_device_fallback.c | |
parent | Initial commit. (diff) | |
download | linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.tar.xz linux-2c3c1048746a4622d8c89a29670120dc8fab93c4.zip |
Adding upstream version 6.1.76.upstream/6.1.76
Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>
Diffstat (limited to 'net/tls/tls_device_fallback.c')
-rw-r--r-- | net/tls/tls_device_fallback.c | 513 |
1 files changed, 513 insertions, 0 deletions
diff --git a/net/tls/tls_device_fallback.c b/net/tls/tls_device_fallback.c new file mode 100644 index 000000000..7fbb1d0b6 --- /dev/null +++ b/net/tls/tls_device_fallback.c @@ -0,0 +1,513 @@ +/* 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 <net/tls.h> +#include <crypto/aead.h> +#include <crypto/scatterwalk.h> +#include <net/ip6_checksum.h> + +#include "tls.h" + +static void chain_to_walk(struct scatterlist *sg, struct scatter_walk *walk) +{ + struct scatterlist *src = walk->sg; + int diff = walk->offset - src->offset; + + sg_set_page(sg, sg_page(src), + src->length - diff, walk->offset); + + scatterwalk_crypto_chain(sg, sg_next(src), 2); +} + +static int tls_enc_record(struct aead_request *aead_req, + struct crypto_aead *aead, char *aad, + char *iv, __be64 rcd_sn, + struct scatter_walk *in, + struct scatter_walk *out, int *in_len, + struct tls_prot_info *prot) +{ + unsigned char buf[TLS_HEADER_SIZE + MAX_IV_SIZE]; + const struct tls_cipher_size_desc *cipher_sz; + struct scatterlist sg_in[3]; + struct scatterlist sg_out[3]; + unsigned int buf_size; + u16 len; + int rc; + + switch (prot->cipher_type) { + case TLS_CIPHER_AES_GCM_128: + case TLS_CIPHER_AES_GCM_256: + break; + default: + return -EINVAL; + } + cipher_sz = &tls_cipher_size_desc[prot->cipher_type]; + + buf_size = TLS_HEADER_SIZE + cipher_sz->iv; + len = min_t(int, *in_len, buf_size); + + scatterwalk_copychunks(buf, in, len, 0); + scatterwalk_copychunks(buf, out, len, 1); + + *in_len -= len; + if (!*in_len) + return 0; + + scatterwalk_pagedone(in, 0, 1); + scatterwalk_pagedone(out, 1, 1); + + len = buf[4] | (buf[3] << 8); + len -= cipher_sz->iv; + + tls_make_aad(aad, len - cipher_sz->tag, (char *)&rcd_sn, buf[0], prot); + + memcpy(iv + cipher_sz->salt, buf + TLS_HEADER_SIZE, cipher_sz->iv); + + sg_init_table(sg_in, ARRAY_SIZE(sg_in)); + sg_init_table(sg_out, ARRAY_SIZE(sg_out)); + sg_set_buf(sg_in, aad, TLS_AAD_SPACE_SIZE); + sg_set_buf(sg_out, aad, TLS_AAD_SPACE_SIZE); + chain_to_walk(sg_in + 1, in); + chain_to_walk(sg_out + 1, out); + + *in_len -= len; + if (*in_len < 0) { + *in_len += cipher_sz->tag; + /* the input buffer doesn't contain the entire record. + * trim len accordingly. The resulting authentication tag + * will contain garbage, but we don't care, so we won't + * include any of it in the output skb + * Note that we assume the output buffer length + * is larger then input buffer length + tag size + */ + if (*in_len < 0) + len += *in_len; + + *in_len = 0; + } + + if (*in_len) { + scatterwalk_copychunks(NULL, in, len, 2); + scatterwalk_pagedone(in, 0, 1); + scatterwalk_copychunks(NULL, out, len, 2); + scatterwalk_pagedone(out, 1, 1); + } + + len -= cipher_sz->tag; + aead_request_set_crypt(aead_req, sg_in, sg_out, len, iv); + + rc = crypto_aead_encrypt(aead_req); + + return rc; +} + +static void tls_init_aead_request(struct aead_request *aead_req, + struct crypto_aead *aead) +{ + aead_request_set_tfm(aead_req, aead); + aead_request_set_ad(aead_req, TLS_AAD_SPACE_SIZE); +} + +static struct aead_request *tls_alloc_aead_request(struct crypto_aead *aead, + gfp_t flags) +{ + unsigned int req_size = sizeof(struct aead_request) + + crypto_aead_reqsize(aead); + struct aead_request *aead_req; + + aead_req = kzalloc(req_size, flags); + if (aead_req) + tls_init_aead_request(aead_req, aead); + return aead_req; +} + +static int tls_enc_records(struct aead_request *aead_req, + struct crypto_aead *aead, struct scatterlist *sg_in, + struct scatterlist *sg_out, char *aad, char *iv, + u64 rcd_sn, int len, struct tls_prot_info *prot) +{ + struct scatter_walk out, in; + int rc; + + scatterwalk_start(&in, sg_in); + scatterwalk_start(&out, sg_out); + + do { + rc = tls_enc_record(aead_req, aead, aad, iv, + cpu_to_be64(rcd_sn), &in, &out, &len, prot); + rcd_sn++; + + } while (rc == 0 && len); + + scatterwalk_done(&in, 0, 0); + scatterwalk_done(&out, 1, 0); + + return rc; +} + +/* Can't use icsk->icsk_af_ops->send_check here because the ip addresses + * might have been changed by NAT. + */ +static void update_chksum(struct sk_buff *skb, int headln) +{ + struct tcphdr *th = tcp_hdr(skb); + int datalen = skb->len - headln; + const struct ipv6hdr *ipv6h; + const struct iphdr *iph; + + /* We only changed the payload so if we are using partial we don't + * need to update anything. + */ + if (likely(skb->ip_summed == CHECKSUM_PARTIAL)) + return; + + skb->ip_summed = CHECKSUM_PARTIAL; + skb->csum_start = skb_transport_header(skb) - skb->head; + skb->csum_offset = offsetof(struct tcphdr, check); + + if (skb->sk->sk_family == AF_INET6) { + ipv6h = ipv6_hdr(skb); + th->check = ~csum_ipv6_magic(&ipv6h->saddr, &ipv6h->daddr, + datalen, IPPROTO_TCP, 0); + } else { + iph = ip_hdr(skb); + th->check = ~csum_tcpudp_magic(iph->saddr, iph->daddr, datalen, + IPPROTO_TCP, 0); + } +} + +static void complete_skb(struct sk_buff *nskb, struct sk_buff *skb, int headln) +{ + struct sock *sk = skb->sk; + int delta; + + skb_copy_header(nskb, skb); + + skb_put(nskb, skb->len); + memcpy(nskb->data, skb->data, headln); + + nskb->destructor = skb->destructor; + nskb->sk = sk; + skb->destructor = NULL; + skb->sk = NULL; + + update_chksum(nskb, headln); + + /* sock_efree means skb must gone through skb_orphan_partial() */ + if (nskb->destructor == sock_efree) + return; + + delta = nskb->truesize - skb->truesize; + if (likely(delta < 0)) + WARN_ON_ONCE(refcount_sub_and_test(-delta, &sk->sk_wmem_alloc)); + else if (delta) + refcount_add(delta, &sk->sk_wmem_alloc); +} + +/* This function may be called after the user socket is already + * closed so make sure we don't use anything freed during + * tls_sk_proto_close here + */ + +static int fill_sg_in(struct scatterlist *sg_in, + struct sk_buff *skb, + struct tls_offload_context_tx *ctx, + u64 *rcd_sn, + s32 *sync_size, + int *resync_sgs) +{ + int tcp_payload_offset = skb_tcp_all_headers(skb); + int payload_len = skb->len - tcp_payload_offset; + u32 tcp_seq = ntohl(tcp_hdr(skb)->seq); + struct tls_record_info *record; + unsigned long flags; + int remaining; + int i; + + spin_lock_irqsave(&ctx->lock, flags); + record = tls_get_record(ctx, tcp_seq, rcd_sn); + if (!record) { + spin_unlock_irqrestore(&ctx->lock, flags); + return -EINVAL; + } + + *sync_size = tcp_seq - tls_record_start_seq(record); + if (*sync_size < 0) { + int is_start_marker = tls_record_is_start_marker(record); + + spin_unlock_irqrestore(&ctx->lock, flags); + /* This should only occur if the relevant record was + * already acked. In that case it should be ok + * to drop the packet and avoid retransmission. + * + * There is a corner case where the packet contains + * both an acked and a non-acked record. + * We currently don't handle that case and rely + * on TCP to retranmit a packet that doesn't contain + * already acked payload. + */ + if (!is_start_marker) + *sync_size = 0; + return -EINVAL; + } + + remaining = *sync_size; + for (i = 0; remaining > 0; i++) { + skb_frag_t *frag = &record->frags[i]; + + __skb_frag_ref(frag); + sg_set_page(sg_in + i, skb_frag_page(frag), + skb_frag_size(frag), skb_frag_off(frag)); + + remaining -= skb_frag_size(frag); + + if (remaining < 0) + sg_in[i].length += remaining; + } + *resync_sgs = i; + + spin_unlock_irqrestore(&ctx->lock, flags); + if (skb_to_sgvec(skb, &sg_in[i], tcp_payload_offset, payload_len) < 0) + return -EINVAL; + + return 0; +} + +static void fill_sg_out(struct scatterlist sg_out[3], void *buf, + struct tls_context *tls_ctx, + struct sk_buff *nskb, + int tcp_payload_offset, + int payload_len, + int sync_size, + void *dummy_buf) +{ + const struct tls_cipher_size_desc *cipher_sz = + &tls_cipher_size_desc[tls_ctx->crypto_send.info.cipher_type]; + + sg_set_buf(&sg_out[0], dummy_buf, sync_size); + sg_set_buf(&sg_out[1], nskb->data + tcp_payload_offset, payload_len); + /* Add room for authentication tag produced by crypto */ + dummy_buf += sync_size; + sg_set_buf(&sg_out[2], dummy_buf, cipher_sz->tag); +} + +static struct sk_buff *tls_enc_skb(struct tls_context *tls_ctx, + struct scatterlist sg_out[3], + struct scatterlist *sg_in, + struct sk_buff *skb, + s32 sync_size, u64 rcd_sn) +{ + struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); + int tcp_payload_offset = skb_tcp_all_headers(skb); + int payload_len = skb->len - tcp_payload_offset; + const struct tls_cipher_size_desc *cipher_sz; + void *buf, *iv, *aad, *dummy_buf, *salt; + struct aead_request *aead_req; + struct sk_buff *nskb = NULL; + int buf_len; + + aead_req = tls_alloc_aead_request(ctx->aead_send, GFP_ATOMIC); + if (!aead_req) + return NULL; + + switch (tls_ctx->crypto_send.info.cipher_type) { + case TLS_CIPHER_AES_GCM_128: + salt = tls_ctx->crypto_send.aes_gcm_128.salt; + break; + case TLS_CIPHER_AES_GCM_256: + salt = tls_ctx->crypto_send.aes_gcm_256.salt; + break; + default: + goto free_req; + } + cipher_sz = &tls_cipher_size_desc[tls_ctx->crypto_send.info.cipher_type]; + buf_len = cipher_sz->salt + cipher_sz->iv + TLS_AAD_SPACE_SIZE + + sync_size + cipher_sz->tag; + buf = kmalloc(buf_len, GFP_ATOMIC); + if (!buf) + goto free_req; + + iv = buf; + memcpy(iv, salt, cipher_sz->salt); + aad = buf + cipher_sz->salt + cipher_sz->iv; + dummy_buf = aad + TLS_AAD_SPACE_SIZE; + + nskb = alloc_skb(skb_headroom(skb) + skb->len, GFP_ATOMIC); + if (!nskb) + goto free_buf; + + skb_reserve(nskb, skb_headroom(skb)); + + fill_sg_out(sg_out, buf, tls_ctx, nskb, tcp_payload_offset, + payload_len, sync_size, dummy_buf); + + if (tls_enc_records(aead_req, ctx->aead_send, sg_in, sg_out, aad, iv, + rcd_sn, sync_size + payload_len, + &tls_ctx->prot_info) < 0) + goto free_nskb; + + complete_skb(nskb, skb, tcp_payload_offset); + + /* validate_xmit_skb_list assumes that if the skb wasn't segmented + * nskb->prev will point to the skb itself + */ + nskb->prev = nskb; + +free_buf: + kfree(buf); +free_req: + kfree(aead_req); + return nskb; +free_nskb: + kfree_skb(nskb); + nskb = NULL; + goto free_buf; +} + +static struct sk_buff *tls_sw_fallback(struct sock *sk, struct sk_buff *skb) +{ + int tcp_payload_offset = skb_tcp_all_headers(skb); + struct tls_context *tls_ctx = tls_get_ctx(sk); + struct tls_offload_context_tx *ctx = tls_offload_ctx_tx(tls_ctx); + int payload_len = skb->len - tcp_payload_offset; + struct scatterlist *sg_in, sg_out[3]; + struct sk_buff *nskb = NULL; + int sg_in_max_elements; + int resync_sgs = 0; + s32 sync_size = 0; + u64 rcd_sn; + + /* worst case is: + * MAX_SKB_FRAGS in tls_record_info + * MAX_SKB_FRAGS + 1 in SKB head and frags. + */ + sg_in_max_elements = 2 * MAX_SKB_FRAGS + 1; + + if (!payload_len) + return skb; + + sg_in = kmalloc_array(sg_in_max_elements, sizeof(*sg_in), GFP_ATOMIC); + if (!sg_in) + goto free_orig; + + sg_init_table(sg_in, sg_in_max_elements); + sg_init_table(sg_out, ARRAY_SIZE(sg_out)); + + if (fill_sg_in(sg_in, skb, ctx, &rcd_sn, &sync_size, &resync_sgs)) { + /* bypass packets before kernel TLS socket option was set */ + if (sync_size < 0 && payload_len <= -sync_size) + nskb = skb_get(skb); + goto put_sg; + } + + nskb = tls_enc_skb(tls_ctx, sg_out, sg_in, skb, sync_size, rcd_sn); + +put_sg: + while (resync_sgs) + put_page(sg_page(&sg_in[--resync_sgs])); + kfree(sg_in); +free_orig: + if (nskb) + consume_skb(skb); + else + kfree_skb(skb); + return nskb; +} + +struct sk_buff *tls_validate_xmit_skb(struct sock *sk, + struct net_device *dev, + struct sk_buff *skb) +{ + if (dev == rcu_dereference_bh(tls_get_ctx(sk)->netdev) || + netif_is_bond_master(dev)) + return skb; + + return tls_sw_fallback(sk, skb); +} +EXPORT_SYMBOL_GPL(tls_validate_xmit_skb); + +struct sk_buff *tls_validate_xmit_skb_sw(struct sock *sk, + struct net_device *dev, + struct sk_buff *skb) +{ + return tls_sw_fallback(sk, skb); +} + +struct sk_buff *tls_encrypt_skb(struct sk_buff *skb) +{ + return tls_sw_fallback(skb->sk, skb); +} +EXPORT_SYMBOL_GPL(tls_encrypt_skb); + +int tls_sw_fallback_init(struct sock *sk, + struct tls_offload_context_tx *offload_ctx, + struct tls_crypto_info *crypto_info) +{ + const struct tls_cipher_size_desc *cipher_sz; + const u8 *key; + int rc; + + offload_ctx->aead_send = + crypto_alloc_aead("gcm(aes)", 0, CRYPTO_ALG_ASYNC); + if (IS_ERR(offload_ctx->aead_send)) { + rc = PTR_ERR(offload_ctx->aead_send); + pr_err_ratelimited("crypto_alloc_aead failed rc=%d\n", rc); + offload_ctx->aead_send = NULL; + goto err_out; + } + + switch (crypto_info->cipher_type) { + case TLS_CIPHER_AES_GCM_128: + key = ((struct tls12_crypto_info_aes_gcm_128 *)crypto_info)->key; + break; + case TLS_CIPHER_AES_GCM_256: + key = ((struct tls12_crypto_info_aes_gcm_256 *)crypto_info)->key; + break; + default: + rc = -EINVAL; + goto free_aead; + } + cipher_sz = &tls_cipher_size_desc[crypto_info->cipher_type]; + + rc = crypto_aead_setkey(offload_ctx->aead_send, key, cipher_sz->key); + if (rc) + goto free_aead; + + rc = crypto_aead_setauthsize(offload_ctx->aead_send, cipher_sz->tag); + if (rc) + goto free_aead; + + return 0; +free_aead: + crypto_free_aead(offload_ctx->aead_send); +err_out: + return rc; +} |