From 034dd340b08be1f2f0477ad16131d609f9dbd53c Mon Sep 17 00:00:00 2001 From: Linus Torvalds Date: Sun, 30 Aug 2026 09:22:00 -0700 Subject: Merge tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace Pull tracing fixes from Steven Rostedt: - Fix error output of boot instance creation failure Currently if a boot instance creation fails, instead of printing out the name of the instance that failed, it prints "(null)". That is because it prints "cur_str" that had already been processed by strsep(). Print the saved name instead. While at it, print the error code of the failure. - Fix use-after-free for same named historgrams Histograms can be named so that they can be used in multiple events. But if the named histogram has a variable attached, the second event that uses the named histogram which duplicates it and needs to free the original after duplication leaves the old variable in place and still visible. If another histogram uses than variable, it will use the stale one which will try to reference the freed duplicate histogram and crash the kernel. Free the duplicate variables along with the duplicated histogram data. - Check return value of kthread_run() in event self test The events self tests uses a kthread for testing but does not check if it succeeded in creating a kthread. If the kthread creation were to fail, the code will still try to call kthread_stop() on the error returned. - Fix race between reading trace_pipe and updating subbuffer size If a user is reading the trace_pipe file at the same time they update the ring buffer sub-buffer size, can cause the trace_pipe read to read stale data. Add trace_access_lock() around updating the ring buffer sub-buffer size. - Fix eventfs_inode on failure path in creation of the events directory In the creation of the "events" directory, if after allocating the eventfs_inode a failure is detected, it calls cleanup_ei() which calls free_ei(). The free_ei() will test if eventfs_inode being freed has no children. It is a bug if it does. But on the failure case of the creation of the "events" directory, the children lists have not yet been initialized and the free will trigger a warning because list_empty() on an uninitialized list returns false. Move the initialization into init_ei() where it makes more sense and makes sure that a created eventfs_inode has its lists initialized upon creation. - Check return value of kthread_run() in ftrace direct sample code The sample code that shows how to use the ftrace direct calls does not test the return of kthread_run() to see if it succeeds. Return a failure if the kthread_run() doesn't succeed. - Clear user events state on fork in case of alloc failure On fork, the child gets a pointer to the parent's user events state. It makes a copy of it then updates the child's pointer to it. But if the allocation fails, the duplication function leaves the child with a pointer to its parent's descriptor. When the child cleans up its data, it will free the parent's descriptor while the parent is still using it. In the duplication function, set the child's user_event_mm to NULL before testing if the allocation succeeded, and when it exits it will not free the parent's descriptor. - Fix retry exhaustion in simple ring buffer reader swap simple_ring_buffer_swap_reader_page() starts with retry set to 8 and post-decrements it only after a failed link replacement. On the final attempt, a successful replacement leaves retry at zero, while a failed replacement leaves it at -1. But the check for success expects the retry value to be non-zero and exits with an error on zero. This is the opposite result. Fix it. - Fail nicely when the remote swap_reader_page() returns an error Currently, if the swap_reader_page() of a remote buffer fails, it triggers a WARN_ON_ONCE() and continues normally. Instead, have it exit with an error and a pr_warn() print instead of a full WARNING. * tag 'trace-v7.3-2' of git://git.kernel.org/pub/scm/linux/kernel/git/trace/linux-trace: ring-buffer: Stop remote reader update when page swap fails tracing: Fix retry exhaustion in simple ring buffer reader swap tracing/user_events: Clear copied tracing state before fork duplication samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-multi-modify samples/ftrace: Fix kthread_stop() on ERR_PTR in ftrace-direct-modify eventfs: Initialize ei->children and ei->list in init_ei() tracing: Fix use-after-free in trace_pipe read on sub-buffer order change tracing: Fix crash passing ERR_PTR to kthread_stop() tracing: Fix use-after-free with same-name named triggers tracing: Fix logged instance name on creation failure --- net/ipv4/esp4.c | 1218 +++++++++++++++++++++++++++++++++++++++++++++++++++++++ 1 file changed, 1218 insertions(+) create mode 100644 net/ipv4/esp4.c (limited to 'net/ipv4/esp4.c') diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c new file mode 100644 index 000000000..a6c18aea7 --- /dev/null +++ b/net/ipv4/esp4.c @@ -0,0 +1,1218 @@ +// SPDX-License-Identifier: GPL-2.0-only +#define pr_fmt(fmt) "IPsec: " fmt + +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include +#include + +#include + +struct esp_skb_cb { + struct xfrm_skb_cb xfrm; + void *tmp; +}; + +struct esp_output_extra { + __be32 seqhi; + u32 esphoff; +}; + +#define ESP_SKB_CB(__skb) ((struct esp_skb_cb *)&((__skb)->cb[0])) + +/* + * Allocate an AEAD request structure with extra space for SG and IV. + * + * For alignment considerations the IV is placed at the front, followed + * by the request and finally the SG list. + * + * TODO: Use spare space in skb for this where possible. + */ +static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int extralen) +{ + unsigned int len; + + len = extralen; + + len += crypto_aead_ivsize(aead); + + if (len) { + len += crypto_aead_alignmask(aead) & + ~(crypto_tfm_ctx_alignment() - 1); + len = ALIGN(len, crypto_tfm_ctx_alignment()); + } + + len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); + len = ALIGN(len, __alignof__(struct scatterlist)); + + len += sizeof(struct scatterlist) * nfrags; + + return kmalloc(len, GFP_ATOMIC); +} + +static inline void *esp_tmp_extra(void *tmp) +{ + return PTR_ALIGN(tmp, __alignof__(struct esp_output_extra)); +} + +static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int extralen) +{ + return crypto_aead_ivsize(aead) ? + PTR_ALIGN((u8 *)tmp + extralen, + crypto_aead_alignmask(aead) + 1) : tmp + extralen; +} + +static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) +{ + struct aead_request *req; + + req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), + crypto_tfm_ctx_alignment()); + aead_request_set_tfm(req, aead); + return req; +} + +static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, + struct aead_request *req) +{ + return (void *)ALIGN((unsigned long)(req + 1) + + crypto_aead_reqsize(aead), + __alignof__(struct scatterlist)); +} + +static void esp_ssg_unref(struct xfrm_state *x, void *tmp, struct sk_buff *skb, bool already_unref) +{ + struct crypto_aead *aead = x->data; + int extralen = 0; + u8 *iv; + struct aead_request *req; + struct scatterlist *sg; + + if (x->props.flags & XFRM_STATE_ESN) + extralen += sizeof(struct esp_output_extra); + + iv = esp_tmp_iv(aead, tmp, extralen); + req = esp_tmp_req(aead, iv); + + /* Unref skb_frag_pages in the src scatterlist if necessary. + * Skip the first sg which comes from skb->data. + */ + if (already_unref || req->src != req->dst) { + struct scatterlist *src = already_unref ? esp_req_sg(aead, req) : req->src; + + for (sg = sg_next(src); sg; sg = sg_next(sg)) + skb_page_unref(page_to_netmem(sg_page(sg)), + skb->pp_recycle); + } +} + +#ifdef CONFIG_INET_ESPINTCP +static struct sock *esp_find_tcp_sk(struct xfrm_state *x) +{ + struct xfrm_encap_tmpl *encap = x->encap; + struct net *net = xs_net(x); + __be16 sport, dport; + struct sock *sk; + + spin_lock_bh(&x->lock); + sport = encap->encap_sport; + dport = encap->encap_dport; + spin_unlock_bh(&x->lock); + + sk = inet_lookup_established(net, x->id.daddr.a4, dport, + x->props.saddr.a4, sport, 0); + if (!sk) + return ERR_PTR(-ENOENT); + + if (!tcp_is_ulp_esp(sk)) { + sock_put(sk); + return ERR_PTR(-EINVAL); + } + + return sk; +} + +static int esp_output_tcp_finish(struct xfrm_state *x, struct sk_buff *skb) +{ + struct sock *sk; + int err; + + rcu_read_lock(); + + sk = esp_find_tcp_sk(x); + err = PTR_ERR_OR_ZERO(sk); + if (err) { + kfree_skb(skb); + goto out; + } + + bh_lock_sock(sk); + if (sock_owned_by_user(sk)) + err = espintcp_queue_out(sk, skb); + else + err = espintcp_push_skb(sk, skb); + bh_unlock_sock(sk); + + sock_put(sk); + +out: + rcu_read_unlock(); + return err; +} + +static int esp_output_tcp_encap_cb(struct net *net, struct sock *sk, + struct sk_buff *skb) +{ + struct dst_entry *dst = skb_dst(skb); + struct xfrm_state *x = dst->xfrm; + + return esp_output_tcp_finish(x, skb); +} + +static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb) +{ + int err; + + local_bh_disable(); + err = xfrm_trans_queue_net(xs_net(x), skb, esp_output_tcp_encap_cb); + local_bh_enable(); + + /* EINPROGRESS just happens to do the right thing. It + * actually means that the skb has been consumed and + * isn't coming back. + */ + return err ?: -EINPROGRESS; +} +#else +static int esp_output_tail_tcp(struct xfrm_state *x, struct sk_buff *skb) +{ + WARN_ON(1); + return -EOPNOTSUPP; +} +#endif + +static void esp_output_done(void *data, int err) +{ + struct sk_buff *skb = data; + struct xfrm_offload *xo = xfrm_offload(skb); + void *tmp; + struct xfrm_state *x; + + if (xo && (xo->flags & XFRM_DEV_RESUME)) { + struct sec_path *sp = skb_sec_path(skb); + + x = sp->xvec[sp->len - 1]; + } else { + x = skb_dst(skb)->xfrm; + } + + tmp = ESP_SKB_CB(skb)->tmp; + esp_ssg_unref(x, tmp, skb, false); + kfree(tmp); + + if (xo && (xo->flags & XFRM_DEV_RESUME)) { + if (err) { + XFRM_INC_STATS(xs_net(x), LINUX_MIB_XFRMOUTSTATEPROTOERROR); + kfree_skb(skb); + return; + } + + skb_push(skb, skb->data - skb_mac_header(skb)); + secpath_reset(skb); + xfrm_dev_resume(skb); + } else { + if (!err && + x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP) { + err = esp_output_tail_tcp(x, skb); + if (err != -EINPROGRESS) + kfree_skb(skb); + } else { + xfrm_output_resume(skb_to_full_sk(skb), skb, err); + } + } +} + +/* Move ESP header back into place. */ +static void esp_restore_header(struct sk_buff *skb, unsigned int offset) +{ + struct ip_esp_hdr *esph = (void *)(skb->data + offset); + void *tmp = ESP_SKB_CB(skb)->tmp; + __be32 *seqhi = esp_tmp_extra(tmp); + + esph->seq_no = esph->spi; + esph->spi = *seqhi; +} + +static void esp_output_restore_header(struct sk_buff *skb) +{ + void *tmp = ESP_SKB_CB(skb)->tmp; + struct esp_output_extra *extra = esp_tmp_extra(tmp); + + esp_restore_header(skb, skb_transport_offset(skb) + extra->esphoff - + sizeof(__be32)); +} + +static struct ip_esp_hdr *esp_output_set_extra(struct sk_buff *skb, + struct xfrm_state *x, + struct ip_esp_hdr *esph, + struct esp_output_extra *extra) +{ + /* For ESN we move the header forward by 4 bytes to + * accommodate the high bits. We will move it back after + * encryption. + */ + if ((x->props.flags & XFRM_STATE_ESN)) { + __u32 seqhi; + struct xfrm_offload *xo = xfrm_offload(skb); + + if (xo) + seqhi = xo->seq.hi; + else + seqhi = XFRM_SKB_CB(skb)->seq.output.hi; + + extra->esphoff = (unsigned char *)esph - + skb_transport_header(skb); + esph = (struct ip_esp_hdr *)((unsigned char *)esph - 4); + extra->seqhi = esph->spi; + esph->seq_no = htonl(seqhi); + } + + esph->spi = x->id.spi; + + return esph; +} + +static void esp_output_done_esn(void *data, int err) +{ + struct sk_buff *skb = data; + + esp_output_restore_header(skb); + esp_output_done(data, err); +} + +static struct ip_esp_hdr *esp_output_udp_encap(struct sk_buff *skb, + int encap_type, + struct esp_info *esp, + __be16 sport, + __be16 dport) +{ + struct udphdr *uh; + unsigned int len; + struct xfrm_offload *xo = xfrm_offload(skb); + + len = skb->len + esp->tailen - skb_transport_offset(skb); + if (len + sizeof(struct iphdr) > IP_MAX_MTU) + return ERR_PTR(-EMSGSIZE); + + uh = (struct udphdr *)esp->esph; + uh->source = sport; + uh->dest = dport; + udp_set_len_short(uh, len); + uh->check = 0; + + /* For IPv4 ESP with UDP encapsulation, if xo is not null, the skb is in the crypto offload + * data path, which means that esp_output_udp_encap is called outside of the XFRM stack. + * In this case, the mac header doesn't point to the IPv4 protocol field, so don't set it. + */ + if (!xo || encap_type != UDP_ENCAP_ESPINUDP) + *skb_mac_header(skb) = IPPROTO_UDP; + + return (struct ip_esp_hdr *)(uh + 1); +} + +#ifdef CONFIG_INET_ESPINTCP +static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x, + struct sk_buff *skb, + struct esp_info *esp) +{ + __be16 *lenp = (void *)esp->esph; + struct ip_esp_hdr *esph; + unsigned int len; + struct sock *sk; + + len = skb->len + esp->tailen - skb_transport_offset(skb); + if (len > IP_MAX_MTU) + return ERR_PTR(-EMSGSIZE); + + rcu_read_lock(); + sk = esp_find_tcp_sk(x); + rcu_read_unlock(); + + if (IS_ERR(sk)) + return ERR_CAST(sk); + + sock_put(sk); + + *lenp = htons(len); + esph = (struct ip_esp_hdr *)(lenp + 1); + + return esph; +} +#else +static struct ip_esp_hdr *esp_output_tcp_encap(struct xfrm_state *x, + struct sk_buff *skb, + struct esp_info *esp) +{ + return ERR_PTR(-EOPNOTSUPP); +} +#endif + +static int esp_output_encap(struct xfrm_state *x, struct sk_buff *skb, + struct esp_info *esp) +{ + struct xfrm_encap_tmpl *encap = x->encap; + struct ip_esp_hdr *esph; + __be16 sport, dport; + int encap_type; + + spin_lock_bh(&x->lock); + sport = encap->encap_sport; + dport = encap->encap_dport; + encap_type = encap->encap_type; + spin_unlock_bh(&x->lock); + + switch (encap_type) { + default: + case UDP_ENCAP_ESPINUDP: + esph = esp_output_udp_encap(skb, encap_type, esp, sport, dport); + break; + case TCP_ENCAP_ESPINTCP: + esph = esp_output_tcp_encap(x, skb, esp); + break; + } + + if (IS_ERR(esph)) + return PTR_ERR(esph); + + esp->esph = esph; + + return 0; +} + +int esp_output_head(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) +{ + u8 *tail; + int nfrags; + int esph_offset; + struct page *page; + struct sk_buff *trailer; + int tailen = esp->tailen; + + /* this is non-NULL only with TCP/UDP Encapsulation */ + if (x->encap) { + int err = esp_output_encap(x, skb, esp); + + if (err < 0) + return err; + } + + if (ALIGN(skb->data_len + tailen, L1_CACHE_BYTES) > + PAGE_SIZE) + goto cow; + + if (!skb_cloned(skb)) { + if (tailen <= skb_tailroom(skb)) { + nfrags = 1; + trailer = skb; + tail = skb_tail_pointer(trailer); + + goto skip_cow; + } else if ((skb_shinfo(skb)->nr_frags < MAX_SKB_FRAGS) + && !skb_has_frag_list(skb)) { + int allocsize; + struct sock *sk = skb->sk; + struct page_frag *pfrag = &x->xfrag; + + esp->inplace = false; + + allocsize = ALIGN(tailen, L1_CACHE_BYTES); + + spin_lock_bh(&x->lock); + + if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { + spin_unlock_bh(&x->lock); + goto cow; + } + + page = pfrag->page; + get_page(page); + + tail = page_address(page) + pfrag->offset; + + esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); + + nfrags = skb_shinfo(skb)->nr_frags; + + __skb_fill_page_desc(skb, nfrags, page, pfrag->offset, + tailen); + skb_shinfo(skb)->nr_frags = ++nfrags; + + pfrag->offset = pfrag->offset + allocsize; + + spin_unlock_bh(&x->lock); + + nfrags++; + + skb_len_add(skb, tailen); + if (sk && sk_fullsock(sk)) + refcount_add(tailen, &sk->sk_wmem_alloc); + + goto out; + } + } + +cow: + esph_offset = (unsigned char *)esp->esph - skb_transport_header(skb); + + nfrags = skb_cow_data(skb, tailen, &trailer); + if (nfrags < 0) + goto out; + tail = skb_tail_pointer(trailer); + esp->esph = (struct ip_esp_hdr *)(skb_transport_header(skb) + esph_offset); + +skip_cow: + esp_output_fill_trailer(tail, esp->tfclen, esp->plen, esp->proto); + pskb_put(skb, trailer, tailen); + +out: + return nfrags; +} +EXPORT_SYMBOL_GPL(esp_output_head); + +int esp_output_tail(struct xfrm_state *x, struct sk_buff *skb, struct esp_info *esp) +{ + u8 *iv; + int alen; + void *tmp; + int ivlen; + int assoclen; + int extralen; + struct page *page; + struct ip_esp_hdr *esph; + struct crypto_aead *aead; + struct aead_request *req; + struct scatterlist *sg, *dsg; + struct esp_output_extra *extra; + int err = -ENOMEM; + + assoclen = sizeof(struct ip_esp_hdr); + extralen = 0; + + if (x->props.flags & XFRM_STATE_ESN) { + extralen += sizeof(*extra); + assoclen += sizeof(__be32); + } + + aead = x->data; + alen = crypto_aead_authsize(aead); + ivlen = crypto_aead_ivsize(aead); + + tmp = esp_alloc_tmp(aead, esp->nfrags + 2, extralen); + if (!tmp) + goto error; + + extra = esp_tmp_extra(tmp); + iv = esp_tmp_iv(aead, tmp, extralen); + req = esp_tmp_req(aead, iv); + sg = esp_req_sg(aead, req); + + if (esp->inplace) + dsg = sg; + else + dsg = &sg[esp->nfrags]; + + esph = esp_output_set_extra(skb, x, esp->esph, extra); + esp->esph = esph; + + sg_init_table(sg, esp->nfrags); + err = skb_to_sgvec(skb, sg, + (unsigned char *)esph - skb->data, + assoclen + ivlen + esp->clen + alen); + if (unlikely(err < 0)) + goto error_free; + + if (!esp->inplace) { + int allocsize; + struct page_frag *pfrag = &x->xfrag; + + allocsize = ALIGN(skb->data_len, L1_CACHE_BYTES); + + spin_lock_bh(&x->lock); + if (unlikely(!skb_page_frag_refill(allocsize, pfrag, GFP_ATOMIC))) { + spin_unlock_bh(&x->lock); + goto error_free; + } + + skb_shinfo(skb)->nr_frags = 1; + + page = pfrag->page; + get_page(page); + /* replace page frags in skb with new page */ + __skb_fill_page_desc(skb, 0, page, pfrag->offset, skb->data_len); + pfrag->offset = pfrag->offset + allocsize; + spin_unlock_bh(&x->lock); + + sg_init_table(dsg, skb_shinfo(skb)->nr_frags + 1); + err = skb_to_sgvec(skb, dsg, + (unsigned char *)esph - skb->data, + assoclen + ivlen + esp->clen + alen); + if (unlikely(err < 0)) { + esp_ssg_unref(x, tmp, skb, true); + goto error_free; + } + } + + if ((x->props.flags & XFRM_STATE_ESN)) + aead_request_set_callback(req, 0, esp_output_done_esn, skb); + else + aead_request_set_callback(req, 0, esp_output_done, skb); + + aead_request_set_crypt(req, sg, dsg, ivlen + esp->clen, iv); + aead_request_set_ad(req, assoclen); + + memset(iv, 0, ivlen); + memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&esp->seqno + 8 - min(ivlen, 8), + min(ivlen, 8)); + + ESP_SKB_CB(skb)->tmp = tmp; + err = crypto_aead_encrypt(req); + + switch (err) { + case -EINPROGRESS: + goto error; + + case -ENOSPC: + err = NET_XMIT_DROP; + break; + + case 0: + if ((x->props.flags & XFRM_STATE_ESN)) + esp_output_restore_header(skb); + } + + if (sg != dsg) + esp_ssg_unref(x, tmp, skb, false); + + if (!err && x->encap && x->encap->encap_type == TCP_ENCAP_ESPINTCP) + err = esp_output_tail_tcp(x, skb); + +error_free: + kfree(tmp); +error: + return err; +} +EXPORT_SYMBOL_GPL(esp_output_tail); + +static int esp_output(struct xfrm_state *x, struct sk_buff *skb) +{ + int alen; + int blksize; + struct ip_esp_hdr *esph; + struct crypto_aead *aead; + struct esp_info esp; + + esp.inplace = true; + + esp.proto = *skb_mac_header(skb); + *skb_mac_header(skb) = IPPROTO_ESP; + + /* skb is pure payload to encrypt */ + + aead = x->data; + alen = crypto_aead_authsize(aead); + + esp.tfclen = 0; + if (x->tfcpad) { + struct xfrm_dst *dst = (struct xfrm_dst *)skb_dst(skb); + u32 padto; + + padto = min(x->tfcpad, xfrm_state_mtu(x, dst->child_mtu_cached)); + if (skb->len < padto) + esp.tfclen = padto - skb->len; + } + 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); + + esp.nfrags = esp_output_head(x, skb, &esp); + if (esp.nfrags < 0) + return esp.nfrags; + + esph = esp.esph; + esph->spi = x->id.spi; + + esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); + esp.seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + + ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); + + skb_push(skb, -skb_network_offset(skb)); + + return esp_output_tail(x, skb, &esp); +} + +static inline int esp_remove_trailer(struct sk_buff *skb) +{ + struct xfrm_state *x = xfrm_input_state(skb); + struct crypto_aead *aead = x->data; + int alen, hlen, elen; + int padlen, trimlen; + __wsum csumdiff; + u8 nexthdr[2]; + int ret; + + alen = crypto_aead_authsize(aead); + hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); + elen = skb->len - hlen; + + if (skb_copy_bits(skb, skb->len - alen - 2, nexthdr, 2)) + BUG(); + + ret = -EINVAL; + padlen = nexthdr[0]; + if (padlen + 2 + alen >= elen) { + net_dbg_ratelimited("ipsec esp packet is garbage padlen=%d, elen=%d\n", + padlen + 2, elen - alen); + goto out; + } + + trimlen = alen + padlen + 2; + if (skb->ip_summed == CHECKSUM_COMPLETE) { + csumdiff = skb_checksum(skb, skb->len - trimlen, trimlen, 0); + skb->csum = csum_block_sub(skb->csum, csumdiff, + skb->len - trimlen); + } + ret = pskb_trim(skb, skb->len - trimlen); + if (unlikely(ret)) + return ret; + + ret = nexthdr[1]; + +out: + return ret; +} + +int esp_input_done2(struct sk_buff *skb, int err) +{ + const struct iphdr *iph; + struct xfrm_state *x = xfrm_input_state(skb); + struct xfrm_offload *xo = xfrm_offload(skb); + struct crypto_aead *aead = x->data; + int hlen = sizeof(struct ip_esp_hdr) + crypto_aead_ivsize(aead); + int ihl; + + if (!xo || !(xo->flags & CRYPTO_DONE)) + kfree(ESP_SKB_CB(skb)->tmp); + + if (unlikely(err)) + goto out; + + err = esp_remove_trailer(skb); + if (unlikely(err < 0)) + goto out; + + iph = ip_hdr(skb); + ihl = iph->ihl * 4; + + if (x->encap) { + struct xfrm_encap_tmpl *encap = x->encap; + struct tcphdr *th = (void *)(skb_network_header(skb) + ihl); + struct udphdr *uh = (void *)(skb_network_header(skb) + ihl); + __be16 source; + + switch (x->encap->encap_type) { + case TCP_ENCAP_ESPINTCP: + source = th->source; + break; + case UDP_ENCAP_ESPINUDP: + source = uh->source; + break; + default: + WARN_ON_ONCE(1); + err = -EINVAL; + goto out; + } + + /* + * 1) if the NAT-T peer's IP or port changed then + * advertise the change to the keying daemon. + * This is an inbound SA, so just compare + * SRC ports. + */ + if (iph->saddr != x->props.saddr.a4 || + source != encap->encap_sport) { + xfrm_address_t ipaddr; + + ipaddr.a4 = iph->saddr; + km_new_mapping(x, &ipaddr, source); + + /* XXX: perhaps add an extra + * policy check here, to see + * if we should allow or + * reject a packet from a + * different source + * address/port. + */ + } + + /* + * 2) ignore UDP/TCP checksums in case + * of NAT-T in Transport Mode, or + * perform other post-processing fixes + * as per draft-ietf-ipsec-udp-encaps-06, + * section 3.1.2 + */ + if (x->props.mode == XFRM_MODE_TRANSPORT) + skb->ip_summed = CHECKSUM_UNNECESSARY; + } + + skb_pull_rcsum(skb, hlen); + if (x->props.mode == XFRM_MODE_TUNNEL || + x->props.mode == XFRM_MODE_IPTFS) + skb_reset_transport_header(skb); + else + skb_set_transport_header(skb, -ihl); + + /* RFC4303: Drop dummy packets without any error */ + if (err == IPPROTO_NONE) + err = -EINVAL; + +out: + return err; +} +EXPORT_SYMBOL_GPL(esp_input_done2); + +static void esp_input_done(void *data, int err) +{ + struct sk_buff *skb = data; + + xfrm_input_resume(skb, esp_input_done2(skb, err)); +} + +static void esp_input_restore_header(struct sk_buff *skb) +{ + esp_restore_header(skb, 0); + __skb_pull(skb, 4); +} + +static void esp_input_set_header(struct sk_buff *skb, __be32 *seqhi) +{ + struct xfrm_state *x = xfrm_input_state(skb); + struct ip_esp_hdr *esph; + + /* For ESN we move the header forward by 4 bytes to + * accommodate the high bits. We will move it back after + * decryption. + */ + if ((x->props.flags & XFRM_STATE_ESN)) { + esph = skb_push(skb, 4); + *seqhi = esph->spi; + esph->spi = esph->seq_no; + esph->seq_no = XFRM_SKB_CB(skb)->seq.input.hi; + } +} + +static void esp_input_done_esn(void *data, int err) +{ + struct sk_buff *skb = data; + + esp_input_restore_header(skb); + esp_input_done(data, err); +} + +/* + * Note: detecting truncated vs. non-truncated authentication data is very + * expensive, so we only support truncated data, which is the recommended + * and common case. + */ +static int esp_input(struct xfrm_state *x, struct sk_buff *skb) +{ + struct crypto_aead *aead = x->data; + struct aead_request *req; + struct sk_buff *trailer; + int ivlen = crypto_aead_ivsize(aead); + int elen = skb->len - sizeof(struct ip_esp_hdr) - ivlen; + int nfrags; + int assoclen; + int seqhilen; + __be32 *seqhi; + void *tmp; + u8 *iv; + struct scatterlist *sg; + int err = -EINVAL; + + if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr) + ivlen)) + goto out; + + if (elen <= 0) + goto out; + + assoclen = sizeof(struct ip_esp_hdr); + seqhilen = 0; + + if (x->props.flags & XFRM_STATE_ESN) { + seqhilen += sizeof(__be32); + assoclen += seqhilen; + } + + if (!skb_cloned(skb)) { + if (!skb_is_nonlinear(skb)) { + nfrags = 1; + + goto skip_cow; + } else if (!skb_has_frag_list(skb) && + !skb_has_shared_frag(skb)) { + nfrags = skb_shinfo(skb)->nr_frags; + nfrags++; + + goto skip_cow; + } + } + + err = skb_cow_data(skb, 0, &trailer); + if (err < 0) + goto out; + + nfrags = err; + +skip_cow: + err = -ENOMEM; + tmp = esp_alloc_tmp(aead, nfrags, seqhilen); + if (!tmp) + goto out; + + ESP_SKB_CB(skb)->tmp = tmp; + seqhi = esp_tmp_extra(tmp); + iv = esp_tmp_iv(aead, tmp, seqhilen); + req = esp_tmp_req(aead, iv); + sg = esp_req_sg(aead, req); + + esp_input_set_header(skb, seqhi); + + sg_init_table(sg, nfrags); + err = skb_to_sgvec(skb, sg, 0, skb->len); + if (unlikely(err < 0)) { + kfree(tmp); + goto out; + } + + skb->ip_summed = CHECKSUM_NONE; + + if ((x->props.flags & XFRM_STATE_ESN)) + aead_request_set_callback(req, 0, esp_input_done_esn, skb); + else + aead_request_set_callback(req, 0, esp_input_done, skb); + + aead_request_set_crypt(req, sg, sg, elen + ivlen, iv); + aead_request_set_ad(req, assoclen); + + err = crypto_aead_decrypt(req); + if (err == -EINPROGRESS) + goto out; + + if ((x->props.flags & XFRM_STATE_ESN)) + esp_input_restore_header(skb); + + err = esp_input_done2(skb, err); + +out: + return err; +} + +static int esp4_err(struct sk_buff *skb, u32 info) +{ + struct net *net = dev_net(skb->dev); + 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; + + switch (icmp_hdr(skb)->type) { + case ICMP_DEST_UNREACH: + if (icmp_hdr(skb)->code != ICMP_FRAG_NEEDED) + return 0; + break; + case ICMP_REDIRECT: + break; + default: + return 0; + } + + x = xfrm_state_lookup(net, skb->mark, (const xfrm_address_t *)&iph->daddr, + esph->spi, IPPROTO_ESP, AF_INET); + if (!x) + return 0; + + if (icmp_hdr(skb)->type == ICMP_DEST_UNREACH) + ipv4_update_pmtu(skb, net, info, 0, IPPROTO_ESP); + else + ipv4_redirect(skb, net, 0, IPPROTO_ESP); + xfrm_state_put(x); + + return 0; +} + +static void esp_destroy(struct xfrm_state *x) +{ + struct crypto_aead *aead = x->data; + + if (!aead) + return; + + crypto_free_aead(aead); +} + +static int esp_init_aead(struct xfrm_state *x, struct netlink_ext_ack *extack) +{ + char aead_name[CRYPTO_MAX_ALG_NAME]; + struct crypto_aead *aead; + int err; + + if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", + x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) { + NL_SET_ERR_MSG(extack, "Algorithm name is too long"); + return -ENAMETOOLONG; + } + + aead = crypto_alloc_aead(aead_name, 0, 0); + err = PTR_ERR(aead); + if (IS_ERR(aead)) + goto error; + + x->data = aead; + + err = crypto_aead_setkey(aead, x->aead->alg_key, + (x->aead->alg_key_len + 7) / 8); + if (err) + goto error; + + err = crypto_aead_setauthsize(aead, x->aead->alg_icv_len / 8); + if (err) + goto error; + + return 0; + +error: + NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); + return err; +} + +static int esp_init_authenc(struct xfrm_state *x, + struct netlink_ext_ack *extack) +{ + struct crypto_aead *aead; + struct crypto_authenc_key_param *param; + struct rtattr *rta; + char *key; + char *p; + char authenc_name[CRYPTO_MAX_ALG_NAME]; + unsigned int keylen; + int err; + + err = -ENAMETOOLONG; + + if ((x->props.flags & XFRM_STATE_ESN)) { + if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, + "%s%sauthencesn(%s,%s)%s", + x->geniv ?: "", x->geniv ? "(" : "", + x->aalg ? x->aalg->alg_name : "digest_null", + x->ealg->alg_name, + x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) { + NL_SET_ERR_MSG(extack, "Algorithm name is too long"); + goto error; + } + } else { + if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, + "%s%sauthenc(%s,%s)%s", + x->geniv ?: "", x->geniv ? "(" : "", + x->aalg ? x->aalg->alg_name : "digest_null", + x->ealg->alg_name, + x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) { + NL_SET_ERR_MSG(extack, "Algorithm name is too long"); + goto error; + } + } + + aead = crypto_alloc_aead(authenc_name, 0, 0); + err = PTR_ERR(aead); + if (IS_ERR(aead)) { + NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); + goto error; + } + + 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)); + err = -ENOMEM; + key = kmalloc(keylen, GFP_KERNEL); + if (!key) + goto error; + + p = key; + rta = (void *)p; + rta->rta_type = CRYPTO_AUTHENC_KEYA_PARAM; + rta->rta_len = RTA_LENGTH(sizeof(*param)); + param = RTA_DATA(rta); + p += RTA_SPACE(sizeof(*param)); + + if (x->aalg) { + struct xfrm_algo_desc *aalg_desc; + + memcpy(p, x->aalg->alg_key, (x->aalg->alg_key_len + 7) / 8); + p += (x->aalg->alg_key_len + 7) / 8; + + aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); + BUG_ON(!aalg_desc); + + err = -EINVAL; + if (aalg_desc->uinfo.auth.icv_fullbits / 8 != + crypto_aead_authsize(aead)) { + NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); + goto free_key; + } + + err = crypto_aead_setauthsize( + aead, x->aalg->alg_trunc_len / 8); + if (err) { + NL_SET_ERR_MSG(extack, "Kernel was unable to initialize cryptographic operations"); + goto free_key; + } + } + + param->enckeylen = cpu_to_be32((x->ealg->alg_key_len + 7) / 8); + memcpy(p, x->ealg->alg_key, (x->ealg->alg_key_len + 7) / 8); + + err = crypto_aead_setkey(aead, key, keylen); + +free_key: + kfree_sensitive(key); + +error: + return err; +} + +static int esp_init_state(struct xfrm_state *x, struct netlink_ext_ack *extack) +{ + struct crypto_aead *aead; + u32 align; + int err; + + x->data = NULL; + + if (x->aead) { + err = esp_init_aead(x, extack); + } else if (x->ealg) { + err = esp_init_authenc(x, extack); + } else { + NL_SET_ERR_MSG(extack, "ESP: AEAD or CRYPT must be provided"); + err = -EINVAL; + } + + if (err) + goto error; + + aead = x->data; + + x->props.header_len = sizeof(struct ip_esp_hdr) + + crypto_aead_ivsize(aead); + if (x->props.mode == XFRM_MODE_TUNNEL) + x->props.header_len += sizeof(struct iphdr); + else if (x->props.mode == XFRM_MODE_BEET && x->sel.family != AF_INET6) + x->props.header_len += IPV4_BEET_PHMAXLEN; + if (x->encap) { + struct xfrm_encap_tmpl *encap = x->encap; + + switch (encap->encap_type) { + default: + NL_SET_ERR_MSG(extack, "Unsupported encapsulation type for ESP"); + err = -EINVAL; + goto error; + case UDP_ENCAP_ESPINUDP: + x->props.header_len += sizeof(struct udphdr); + break; +#ifdef CONFIG_INET_ESPINTCP + case TCP_ENCAP_ESPINTCP: + /* only the length field, TCP encap is done by + * the socket + */ + x->props.header_len += 2; + break; +#endif + } + } + + align = ALIGN(crypto_aead_blocksize(aead), 4); + 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 = +{ + .owner = THIS_MODULE, + .proto = IPPROTO_ESP, + .flags = XFRM_TYPE_REPLAY_PROT, + .init_state = esp_init_state, + .destructor = esp_destroy, + .input = esp_input, + .output = esp_output, +}; + +static struct xfrm4_protocol esp4_protocol = { + .handler = xfrm4_rcv, + .input_handler = xfrm_input, + .cb_handler = esp4_rcv_cb, + .err_handler = esp4_err, + .priority = 0, +}; + +static int __init esp4_init(void) +{ + if (xfrm_register_type(&esp_type, AF_INET) < 0) { + pr_info("%s: can't add xfrm type\n", __func__); + return -EAGAIN; + } + 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; + } + return 0; +} + +static void __exit esp4_fini(void) +{ + if (xfrm4_protocol_deregister(&esp4_protocol, IPPROTO_ESP) < 0) + pr_info("%s: can't remove protocol\n", __func__); + xfrm_unregister_type(&esp_type, AF_INET); +} + +module_init(esp4_init); +module_exit(esp4_fini); +MODULE_DESCRIPTION("IPv4 ESP transformation library"); +MODULE_LICENSE("GPL"); +MODULE_ALIAS_XFRM_TYPE(AF_INET, XFRM_PROTO_ESP); -- cgit v1.3.1