From fca11ebde3f0d1c637550a9b231caa385ce35749 Mon Sep 17 00:00:00 2001 From: Steffen Klassert Date: Fri, 14 Apr 2017 10:06:33 +0200 Subject: esp4: Reorganize esp_output We need a fallback for ESP at layer 2, so split esp_output into generic functions that can be used at layer 3 and layer 2 and use them in esp_output. We also add esp_xmit which is used for the layer 2 fallback. Signed-off-by: Steffen Klassert --- net/ipv4/esp4_offload.c | 102 ++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 102 insertions(+) (limited to 'net/ipv4/esp4_offload.c') diff --git a/net/ipv4/esp4_offload.c b/net/ipv4/esp4_offload.c index 1de442632406..efaaa44e1073 100644 --- a/net/ipv4/esp4_offload.c +++ b/net/ipv4/esp4_offload.c @@ -84,19 +84,121 @@ out: return NULL; } +static int esp_input_tail(struct xfrm_state *x, struct sk_buff *skb) +{ + struct crypto_aead *aead = x->data; + + if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead))) + return -EINVAL; + + skb->ip_summed = CHECKSUM_NONE; + + return esp_input_done2(skb, 0); +} + +static int esp_xmit(struct xfrm_state *x, struct sk_buff *skb, netdev_features_t features) +{ + int err; + int alen; + int blksize; + struct xfrm_offload *xo; + struct ip_esp_hdr *esph; + struct crypto_aead *aead; + struct esp_info esp; + bool hw_offload = true; + + esp.inplace = true; + + xo = xfrm_offload(skb); + + if (!xo) + return -EINVAL; + + if (!(features & NETIF_F_HW_ESP) || + (x->xso.offload_handle && x->xso.dev != skb->dev)) { + xo->flags |= CRYPTO_FALLBACK; + hw_offload = false; + } + + esp.proto = xo->proto; + + /* skb is pure payload to encrypt */ + + aead = x->data; + alen = crypto_aead_authsize(aead); + + esp.tfclen = 0; + /* XXX: Add support for tfc padding here. */ + + blksize = ALIGN(crypto_aead_blocksize(aead), 4); + esp.clen = ALIGN(skb->len + 2 + esp.tfclen, blksize); + esp.plen = esp.clen - skb->len - esp.tfclen; + esp.tailen = esp.tfclen + esp.plen + alen; + + esp.esph = ip_esp_hdr(skb); + + + if (!hw_offload || (hw_offload && !skb_is_gso(skb))) { + esp.nfrags = esp_output_head(x, skb, &esp); + if (esp.nfrags < 0) + return esp.nfrags; + } + + esph = esp.esph; + esph->spi = x->id.spi; + + skb_push(skb, -skb_network_offset(skb)); + + if (xo->flags & XFRM_GSO_SEGMENT) { + esph->seq_no = htonl(xo->seq.low); + } else { + ip_hdr(skb)->tot_len = htons(skb->len); + ip_send_check(ip_hdr(skb)); + } + + if (hw_offload) + return 0; + + esp.seqno = cpu_to_be64(xo->seq.low + ((u64)xo->seq.hi << 32)); + + err = esp_output_tail(x, skb, &esp); + if (err < 0) + return err; + + secpath_reset(skb); + + return 0; +} + static const struct net_offload esp4_offload = { .callbacks = { .gro_receive = esp4_gro_receive, }, }; +static const struct xfrm_type_offload esp_type_offload = { + .description = "ESP4 OFFLOAD", + .owner = THIS_MODULE, + .proto = IPPROTO_ESP, + .input_tail = esp_input_tail, + .xmit = esp_xmit, +}; + static int __init esp4_offload_init(void) { + if (xfrm_register_type_offload(&esp_type_offload, AF_INET) < 0) { + pr_info("%s: can't add xfrm type offload\n", __func__); + return -EAGAIN; + } + return inet_add_offload(&esp4_offload, IPPROTO_ESP); } static void __exit esp4_offload_exit(void) { + if (xfrm_unregister_type_offload(&esp_type_offload, AF_INET) < 0) + pr_info("%s: can't remove xfrm type offload\n", __func__); + inet_del_offload(&esp4_offload, IPPROTO_ESP); } -- cgit v1.2.3-59-g8ed1b