diff options
Diffstat (limited to 'net/ipv4/esp4.c')
| -rw-r--r-- | net/ipv4/esp4.c | 274 |
1 files changed, 176 insertions, 98 deletions
diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 14ca1f1c3fb..360b565918c 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -1,3 +1,5 @@ +#define pr_fmt(fmt) "IPsec: " fmt + #include <crypto/aead.h> #include <crypto/authenc.h> #include <linux/err.h> @@ -23,6 +25,8 @@ struct esp_skb_cb { #define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) +static u32 esp4_get_mtu(struct xfrm_state *x, int mtu); + /* * Allocate an AEAD request structure with extra space for SG and IV. * @@ -31,11 +35,14 @@ struct esp_skb_cb { * * TODO: Use spare space in skb for this where possible. */ -static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags) +static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqhilen) { unsigned int len; - len = crypto_aead_ivsize(aead); + len = seqhilen; + + len += crypto_aead_ivsize(aead); + if (len) { len += crypto_aead_alignmask(aead) & ~(crypto_tfm_ctx_alignment() - 1); @@ -50,10 +57,15 @@ static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags) return kmalloc(len, GFP_ATOMIC); } -static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp) +static inline __be32 *esp_tmp_seqhi(void *tmp) +{ + return PTR_ALIGN((__be32 *)tmp, __alignof__(__be32)); +} +static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) { return crypto_aead_ivsize(aead) ? - PTR_ALIGN((u8 *)tmp, crypto_aead_alignmask(aead) + 1) : tmp; + PTR_ALIGN((u8 *)tmp + seqhilen, + crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; } static inline struct aead_givcrypt_request *esp_tmp_givreq( @@ -109,7 +121,6 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) struct aead_givcrypt_request *req; struct scatterlist *sg; struct scatterlist *asg; - struct esp_data *esp; struct sk_buff *trailer; void *tmp; u8 *iv; @@ -117,46 +128,72 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) int blksize; int clen; int alen; + int plen; + int tfclen; int nfrags; + int assoclen; + int sglists; + int seqhilen; + __be32 *seqhi; /* skb is pure payload to encrypt */ - err = -ENOMEM; - - /* Round to block size */ - clen = skb->len; - - esp = x->data; - aead = esp->aead; + aead = x->data; alen = crypto_aead_authsize(aead); + tfclen = 0; + if (x->tfcpad) { + struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); + u32 padto; + + padto = min(x->tfcpad, esp4_get_mtu(x, dst->child_mtu_cached)); + if (skb->len < padto) + tfclen = padto - skb->len; + } blksize = ALIGN(crypto_aead_blocksize(aead), 4); - clen = ALIGN(clen + 2, blksize); - if (esp->padlen) - clen = ALIGN(clen, esp->padlen); + clen = ALIGN(skb->len + 2 + tfclen, blksize); + plen = clen - skb->len - tfclen; - if ((err = skb_cow_data(skb, clen - skb->len + alen, &trailer)) < 0) + err = skb_cow_data(skb, tfclen + plen + alen, &trailer); + if (err < 0) goto error; nfrags = err; - tmp = esp_alloc_tmp(aead, nfrags + 1); - if (!tmp) + assoclen = sizeof(*esph); + sglists = 1; + seqhilen = 0; + + if (x->props.flags & XFRM_STATE_ESN) { + sglists += 2; + seqhilen += sizeof(__be32); + assoclen += seqhilen; + } + + tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); + if (!tmp) { + err = -ENOMEM; goto error; + } - iv = esp_tmp_iv(aead, tmp); + seqhi = esp_tmp_seqhi(tmp); + iv = esp_tmp_iv(aead, tmp, seqhilen); req = esp_tmp_givreq(aead, iv); asg = esp_givreq_sg(aead, req); - sg = asg + 1; + sg = asg + sglists; /* Fill padding... */ tail = skb_tail_pointer(trailer); + if (tfclen) { + memset(tail, 0, tfclen); + tail += tfclen; + } do { int i; - for (i=0; i<clen-skb->len - 2; i++) + for (i = 0; i < plen - 2; i++) tail[i] = i + 1; } while (0); - tail[clen - skb->len - 2] = (clen - skb->len) - 2; - tail[clen - skb->len - 1] = *skb_mac_header(skb); + tail[plen - 2] = plen - 2; + tail[plen - 1] = *skb_mac_header(skb); pskb_put(skb, trailer, clen - skb->len + alen); skb_push(skb, -skb_network_offset(skb)); @@ -199,19 +236,27 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) } esph->spi = x->id.spi; - esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output); + esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); sg_init_table(sg, nfrags); skb_to_sgvec(skb, sg, esph->enc_data + crypto_aead_ivsize(aead) - skb->data, clen + alen); - sg_init_one(asg, esph, sizeof(*esph)); + + if ((x->props.flags & XFRM_STATE_ESN)) { + sg_init_table(asg, 3); + sg_set_buf(asg, &esph->spi, sizeof(__be32)); + *seqhi = htonl(XFRM_SKB_CB(skb)->seq.output.hi); + sg_set_buf(asg + 1, seqhi, seqhilen); + sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); + } else + sg_init_one(asg, esph, sizeof(*esph)); aead_givcrypt_set_callback(req, 0, esp_output_done, skb); aead_givcrypt_set_crypt(req, sg, sg, clen, iv); - aead_givcrypt_set_assoc(req, asg, sizeof(*esph)); + aead_givcrypt_set_assoc(req, asg, assoclen); aead_givcrypt_set_giv(req, esph->enc_data, - XFRM_SKB_CB(skb)->seq.output); + XFRM_SKB_CB(skb)->seq.output.low); ESP_SKB_CB(skb)->tmp = tmp; err = crypto_aead_givencrypt(req); @@ -229,10 +274,9 @@ error: static int esp_input_done2(struct sk_buff *skb, int err) { - struct iphdr *iph; + const struct iphdr *iph; struct xfrm_state *x = xfrm_input_state(skb); - struct esp_data *esp = x->data; - struct crypto_aead *aead = esp->aead; + struct crypto_aead *aead = x->data; int alen = crypto_aead_authsize(aead); int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); int elen = skb->len - hlen; @@ -297,7 +341,10 @@ static int esp_input_done2(struct sk_buff *skb, int err) pskb_trim(skb, skb->len - alen - padlen - 2); __skb_pull(skb, hlen); - skb_set_transport_header(skb, -ihl); + if (x->props.mode == XFRM_MODE_TUNNEL) + skb_reset_transport_header(skb); + else + skb_set_transport_header(skb, -ihl); err = nexthdr[1]; @@ -324,12 +371,15 @@ static void esp_input_done(struct crypto_async_request *base, int err) static int esp_input(struct xfrm_state *x, struct sk_buff *skb) { struct ip_esp_hdr *esph; - struct esp_data *esp = x->data; - struct crypto_aead *aead = esp->aead; + struct crypto_aead *aead = x->data; struct aead_request *req; struct sk_buff *trailer; int elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead); int nfrags; + int assoclen; + int sglists; + int seqhilen; + __be32 *seqhi; void *tmp; u8 *iv; struct scatterlist *sg; @@ -346,16 +396,27 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) goto out; nfrags = err; + assoclen = sizeof(*esph); + sglists = 1; + seqhilen = 0; + + if (x->props.flags & XFRM_STATE_ESN) { + sglists += 2; + seqhilen += sizeof(__be32); + assoclen += seqhilen; + } + err = -ENOMEM; - tmp = esp_alloc_tmp(aead, nfrags + 1); + tmp = esp_alloc_tmp(aead, nfrags + sglists, seqhilen); if (!tmp) goto out; ESP_SKB_CB(skb)->tmp = tmp; - iv = esp_tmp_iv(aead, tmp); + seqhi = esp_tmp_seqhi(tmp); + iv = esp_tmp_iv(aead, tmp, seqhilen); req = esp_tmp_req(aead, iv); asg = esp_req_sg(aead, req); - sg = asg + 1; + sg = asg + sglists; skb->ip_summed = CHECKSUM_NONE; @@ -366,11 +427,19 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) sg_init_table(sg, nfrags); skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen); - sg_init_one(asg, esph, sizeof(*esph)); + + if ((x->props.flags & XFRM_STATE_ESN)) { + sg_init_table(asg, 3); + sg_set_buf(asg, &esph->spi, sizeof(__be32)); + *seqhi = XFRM_SKB_CB(skb)->seq.input.hi; + sg_set_buf(asg + 1, seqhi, seqhilen); + sg_set_buf(asg + 2, &esph->seq_no, sizeof(__be32)); + } else + sg_init_one(asg, esph, sizeof(*esph)); aead_request_set_callback(req, 0, esp_input_done, skb); aead_request_set_crypt(req, sg, sg, elen, iv); - aead_request_set_assoc(req, asg, sizeof(*esph)); + aead_request_set_assoc(req, asg, assoclen); err = crypto_aead_decrypt(req); if (err == -EINPROGRESS) @@ -384,66 +453,69 @@ out: static u32 esp4_get_mtu(struct xfrm_state *x, int mtu) { - struct esp_data *esp = x->data; - u32 blksize = ALIGN(crypto_aead_blocksize(esp->aead), 4); - u32 align = max_t(u32, blksize, esp->padlen); - u32 rem; - - mtu -= x->props.header_len + crypto_aead_authsize(esp->aead); - rem = mtu & (align - 1); - mtu &= ~(align - 1); + struct crypto_aead *aead = x->data; + u32 blksize = ALIGN(crypto_aead_blocksize(aead), 4); + unsigned int net_adj; switch (x->props.mode) { - case XFRM_MODE_TUNNEL: - break; - default: case XFRM_MODE_TRANSPORT: - /* The worst case */ - mtu -= blksize - 4; - mtu += min_t(u32, blksize - 4, rem); - break; case XFRM_MODE_BEET: - /* The worst case. */ - mtu += min_t(u32, IPV4_BEET_PHMAXLEN, rem); + net_adj = sizeof(struct iphdr); + break; + case XFRM_MODE_TUNNEL: + net_adj = 0; break; + default: + BUG(); } - return mtu - 2; + return ((mtu - x->props.header_len - crypto_aead_authsize(aead) - + net_adj) & ~(blksize - 1)) + net_adj - 2; } -static void esp4_err(struct sk_buff *skb, u32 info) +static int esp4_err(struct sk_buff *skb, u32 info) { struct net *net = dev_net(skb->dev); - struct iphdr *iph = (struct iphdr *)skb->data; + const struct iphdr *iph = (const struct iphdr *)skb->data; struct ip_esp_hdr *esph = (struct ip_esp_hdr *)(skb->data+(iph->ihl<<2)); struct xfrm_state *x; - if (icmp_hdr(skb)->type != ICMP_DEST_UNREACH || - icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) - return; + switch (icmp_hdr(skb)->type) { + case ICMP_DEST_UNREACH: + if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) + return 0; + case ICMP_REDIRECT: + break; + default: + return 0; + } - x = xfrm_state_lookup(net, skb->mark, (xfrm_address_t *)&iph->daddr, esph->spi, IPPROTO_ESP, AF_INET); + x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, + esph->spi, IPPROTO_ESP, AF_INET); if (!x) - return; - NETDEBUG(KERN_DEBUG "pmtu discovery on SA ESP/%08x/%08x\n", - ntohl(esph->spi), ntohl(iph->daddr)); + return 0; + + if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) + ipv4_update_pmtu(skb, net, info, 0, 0, IPPROTO_ESP, 0); + else + ipv4_redirect(skb, net, 0, 0, IPPROTO_ESP, 0); xfrm_state_put(x); + + return 0; } static void esp_destroy(struct xfrm_state *x) { - struct esp_data *esp = x->data; + struct crypto_aead *aead = x->data; - if (!esp) + if (!aead) return; - crypto_free_aead(esp->aead); - kfree(esp); + crypto_free_aead(aead); } static int esp_init_aead(struct xfrm_state *x) { - struct esp_data *esp = x->data; struct crypto_aead *aead; int err; @@ -452,7 +524,7 @@ static int esp_init_aead(struct xfrm_state *x) if (IS_ERR(aead)) goto error; - esp->aead = aead; + x->data = aead; err = crypto_aead_setkey(aead, x->aead->alg_key, (x->aead->alg_key_len + 7) / 8); @@ -469,7 +541,6 @@ error: static int esp_init_authenc(struct xfrm_state *x) { - struct esp_data *esp = x->data; struct crypto_aead *aead; struct crypto_authenc_key_param *param; struct rtattr *rta; @@ -484,17 +555,27 @@ static int esp_init_authenc(struct xfrm_state *x) goto error; err = -ENAMETOOLONG; - if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, "authenc(%s,%s)", - x->aalg ? x->aalg->alg_name : "digest_null", - x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) - goto error; + + if ((x->props.flags & XFRM_STATE_ESN)) { + if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, + "authencesn(%s,%s)", + x->aalg ? x->aalg->alg_name : "digest_null", + x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) + goto error; + } else { + if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, + "authenc(%s,%s)", + x->aalg ? x->aalg->alg_name : "digest_null", + x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) + goto error; + } aead = crypto_alloc_aead(authenc_name, 0, 0); err = PTR_ERR(aead); if (IS_ERR(aead)) goto error; - esp->aead = aead; + x->data = aead; keylen = (x->aalg ? (x->aalg->alg_key_len + 7) / 8 : 0) + (x->ealg->alg_key_len + 7) / 8 + RTA_SPACE(sizeof(*param)); @@ -549,16 +630,11 @@ error: static int esp_init_state(struct xfrm_state *x) { - struct esp_data *esp; struct crypto_aead *aead; u32 align; int err; - esp = kzalloc(sizeof(*esp), GFP_KERNEL); - if (esp == NULL) - return -ENOMEM; - - x->data = esp; + x->data = NULL; if (x->aead) err = esp_init_aead(x); @@ -568,9 +644,7 @@ static int esp_init_state(struct xfrm_state *x) if (err) goto error; - aead = esp->aead; - - esp->padlen = 0; + aead = x->data; x->props.header_len = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); @@ -594,14 +668,17 @@ static int esp_init_state(struct xfrm_state *x) } align = ALIGN(crypto_aead_blocksize(aead), 4); - if (esp->padlen) - align = max_t(u32, align, esp->padlen); - x->props.trailer_len = align + 1 + crypto_aead_authsize(esp->aead); + x->props.trailer_len = align + 1 + crypto_aead_authsize(aead); error: return err; } +static int esp4_rcv_cb(struct sk_buff *skb, int err) +{ + return 0; +} + static const struct xfrm_type esp_type = { .description = "ESP4", @@ -615,21 +692,22 @@ static const struct xfrm_type esp_type = .output = esp_output }; -static const struct net_protocol esp4_protocol = { +static struct xfrm4_protocol esp4_protocol = { .handler = xfrm4_rcv, + .input_handler = xfrm_input, + .cb_handler = esp4_rcv_cb, .err_handler = esp4_err, - .no_policy = 1, - .netns_ok = 1, + .priority = 0, }; static int __init esp4_init(void) { if (xfrm_register_type(&esp_type, AF_INET) < 0) { - printk(KERN_INFO "ip esp init: can't add xfrm type\n"); + pr_info("%s: can't add xfrm type\n", __func__); return -EAGAIN; } - if (inet_add_protocol(&esp4_protocol, IPPROTO_ESP) < 0) { - printk(KERN_INFO "ip esp init: can't add protocol\n"); + if (xfrm4_protocol_register(&esp4_protocol, IPPROTO_ESP) < 0) { + pr_info("%s: can't add protocol\n", __func__); xfrm_unregister_type(&esp_type, AF_INET); return -EAGAIN; } @@ -638,10 +716,10 @@ static int __init esp4_init(void) static void __exit esp4_fini(void) { - if (inet_del_protocol(&esp4_protocol, IPPROTO_ESP) < 0) - printk(KERN_INFO "ip esp close: can't remove protocol\n"); + if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0) + pr_info("%s: can't remove protocol\n", __func__); if (xfrm_unregister_type(&esp_type, AF_INET) < 0) - printk(KERN_INFO "ip esp close: can't remove xfrm type\n"); + pr_info("%s: can't remove xfrm type\n", __func__); } module_init(esp4_init); |
