int esp_output(struct sk_buff *skb) { int err; struct dst_entry *dst = skb->dst; struct xfrm_state *x = dst->xfrm; struct iphdr *iph, *top_iph; struct ip_esp_hdr *esph; struct crypto_tfm *tfm; struct esp_data *esp; struct sk_buff *trailer; struct udphdr *uh = NULL; struct xfrm_encap_tmpl *encap = NULL; int blksize; int clen; int alen; int nfrags; union { struct iphdr iph; char buf[60]; } tmp_iph; /* First, if the skb is not checksummed, complete checksum. */ if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) { err = -EINVAL; goto error_nolock; } spin_lock_bh(&x->lock); err = xfrm_check_output(x, skb, AF_INET); if (err) goto error; err = -ENOMEM; /* Strip IP header in transport mode. Save it. */ if (!x->props.mode) { iph = skb->nh.iph; memcpy(&tmp_iph, iph, iph->ihl*4); __skb_pull(skb, iph->ihl*4); } /* Now skb is pure payload to encrypt */ /* Round to block size */ clen = skb->len; esp = x->data; alen = esp->auth.icv_trunc_len; tfm = esp->conf.tfm; blksize = (crypto_tfm_alg_blocksize(tfm) + 3) & ~3; clen = (clen + 2 + blksize-1)&~(blksize-1); if (esp->conf.padlen) clen = (clen + esp->conf.padlen-1)&~(esp->conf.padlen-1); if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0) goto error; /* Fill padding... */ do { int i; for (i=0; i<clen-skb->len - 2; i++) *(u8*)(trailer->tail + i) = i+1; } while (0); *(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2; pskb_put(skb, trailer, clen - skb->len); encap = x->encap; iph = skb->nh.iph; if (x->props.mode) { top_iph = (struct iphdr*)skb_push(skb, x->props.header_len); esph = (struct ip_esp_hdr*)(top_iph+1); if (encap && encap->encap_type) { switch (encap->encap_type) { case UDP_ENCAP_ESPINUDP: uh = (struct udphdr*) esph; esph = (struct ip_esp_hdr*)(uh+1); top_iph->protocol = IPPROTO_UDP; break; default: printk(KERN_INFO "esp_output(): Unhandled encap: %u\n", encap->encap_type); top_iph->protocol = IPPROTO_ESP; break; } } else top_iph->protocol = IPPROTO_ESP; *(u8*)(trailer->tail - 1) = IPPROTO_IPIP; top_iph->ihl = 5; top_iph->version = 4; top_iph->tos = iph->tos; /* DS disclosed */ if (x->props.flags & XFRM_STATE_NOECN) IP_ECN_clear(top_iph); top_iph->tot_len = htons(skb->len + alen); top_iph->frag_off = iph->frag_off&htons(IP_DF); if (!(top_iph->frag_off)) ip_select_ident(top_iph, dst, 0); top_iph->ttl = iph->ttl; /* TTL disclosed */ top_iph->check = 0; top_iph->saddr = x->props.saddr.a4; top_iph->daddr = x->id.daddr.a4; memset(&(IPCB(skb)->opt), 0, sizeof(struct ip_options)); } else { esph = (struct ip_esp_hdr*)skb_push(skb, x->props.header_len); top_iph = (struct iphdr*)skb_push(skb, iph->ihl*4); memcpy(top_iph, &tmp_iph, iph->ihl*4); if (encap && encap->encap_type) { switch (encap->encap_type) { case UDP_ENCAP_ESPINUDP: uh = (struct udphdr*) esph; esph = (struct ip_esp_hdr*)(uh+1); top_iph->protocol = IPPROTO_UDP; break; default: printk(KERN_INFO "esp_output(): Unhandled encap: %u\n", encap->encap_type); top_iph->protocol = IPPROTO_ESP; break; } } else top_iph->protocol = IPPROTO_ESP; iph = &tmp_iph.iph; top_iph->tot_len = htons(skb->len + alen); top_iph->check = 0; top_iph->frag_off = iph->frag_off; *(u8*)(trailer->tail - 1) = iph->protocol; } /* this is non-NULL only with UDP Encapsulation */ if (encap && uh) { uh->source = encap->encap_sport; uh->dest = encap->encap_dport; uh->len = htons(skb->len + alen - sizeof(struct iphdr)); uh->check = 0; } esph->spi = x->id.spi; esph->seq_no = htonl(++x->replay.oseq); if (esp->conf.ivlen) crypto_cipher_set_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); do { struct scatterlist sgbuf[nfrags>MAX_SG_ONSTACK ? 0 : nfrags]; struct scatterlist *sg = sgbuf; if (unlikely(nfrags > MAX_SG_ONSTACK)) { sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); if (!sg) goto error; } skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen); crypto_cipher_encrypt(tfm, sg, sg, clen); if (unlikely(sg != sgbuf)) kfree(sg); } while (0); if (esp->conf.ivlen) { memcpy(esph->enc_data, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); crypto_cipher_get_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); } if (esp->auth.icv_full_len) { esp->auth.icv(esp, skb, (u8*)esph-skb->data, sizeof(struct ip_esp_hdr) + esp->conf.ivlen+clen, trailer->tail); pskb_put(skb, trailer, alen); } ip_send_check(top_iph); skb->nh.raw = skb->data; x->curlft.bytes += skb->len; x->curlft.packets++; spin_unlock_bh(&x->lock); if ((skb->dst = dst_pop(dst)) == NULL) { err = -EHOSTUNREACH; goto error_nolock; } return NET_XMIT_BYPASS; error: spin_unlock_bh(&x->lock); error_nolock: kfree_skb(skb); return err; }
int esp_init_state(struct xfrm_state *x, void *args) { struct esp_data *esp = NULL; /* null auth and encryption can have zero length keys */ if (x->aalg) { if (x->aalg->alg_key_len > 512) goto error; } if (x->ealg == NULL) goto error; esp = kmalloc(sizeof(*esp), GFP_KERNEL); if (esp == NULL) return -ENOMEM; memset(esp, 0, sizeof(*esp)); if (x->aalg) { struct xfrm_algo_desc *aalg_desc; esp->auth.key = x->aalg->alg_key; esp->auth.key_len = (x->aalg->alg_key_len+7)/8; esp->auth.tfm = crypto_alloc_tfm(x->aalg->alg_name, 0); if (esp->auth.tfm == NULL) goto error; esp->auth.icv = esp_hmac_digest; aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name); BUG_ON(!aalg_desc); if (aalg_desc->uinfo.auth.icv_fullbits/8 != crypto_tfm_alg_digestsize(esp->auth.tfm)) { printk(KERN_INFO "ESP: %s digestsize %u != %hu\n", x->aalg->alg_name, crypto_tfm_alg_digestsize(esp->auth.tfm), aalg_desc->uinfo.auth.icv_fullbits/8); goto error; } esp->auth.icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; esp->auth.icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8; esp->auth.work_icv = kmalloc(esp->auth.icv_full_len, GFP_KERNEL); if (!esp->auth.work_icv) goto error; } esp->conf.key = x->ealg->alg_key; esp->conf.key_len = (x->ealg->alg_key_len+7)/8; if (x->props.ealgo == SADB_EALG_NULL) esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_ECB); else esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_CBC); if (esp->conf.tfm == NULL) goto error; esp->conf.ivlen = crypto_tfm_alg_ivsize(esp->conf.tfm); esp->conf.padlen = 0; if (esp->conf.ivlen) { esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL); get_random_bytes(esp->conf.ivec, esp->conf.ivlen); } crypto_cipher_setkey(esp->conf.tfm, esp->conf.key, esp->conf.key_len); x->props.header_len = sizeof(struct ip_esp_hdr) + esp->conf.ivlen; if (x->props.mode) x->props.header_len += sizeof(struct iphdr); if (x->encap) { struct xfrm_encap_tmpl *encap = x->encap; if (encap->encap_type) { switch (encap->encap_type) { case UDP_ENCAP_ESPINUDP: x->props.header_len += sizeof(struct udphdr); break; default: printk (KERN_INFO "esp_init_state(): Unhandled encap type: %u\n", encap->encap_type); break; } } } x->data = esp; x->props.trailer_len = esp4_get_max_size(x, 0) - x->props.header_len; return 0; error: if (esp) { if (esp->auth.tfm) crypto_free_tfm(esp->auth.tfm); if (esp->auth.work_icv) kfree(esp->auth.work_icv); if (esp->conf.tfm) crypto_free_tfm(esp->conf.tfm); kfree(esp); } return -EINVAL; }
static int esp6_output(struct xfrm_state *x, struct sk_buff *skb) { int err; int hdr_len; struct ipv6hdr *top_iph; struct ipv6_esp_hdr *esph; struct crypto_tfm *tfm; struct esp_data *esp; struct sk_buff *trailer; int blksize; int clen; int alen; int nfrags; esp = x->data; hdr_len = skb->h.raw - skb->data + sizeof(*esph) + esp->conf.ivlen; /* Strip IP+ESP header. */ __skb_pull(skb, hdr_len); /* Now skb is pure payload to encrypt */ err = -ENOMEM; /* Round to block size */ clen = skb->len; alen = esp->auth.icv_trunc_len; tfm = esp->conf.tfm; blksize = ALIGN(crypto_tfm_alg_blocksize(tfm), 4); clen = ALIGN(clen + 2, blksize); if (esp->conf.padlen) clen = ALIGN(clen, esp->conf.padlen); if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0) { goto error; } /* Fill padding... */ do { int i; for (i=0; i<clen-skb->len - 2; i++) *(u8*)(trailer->tail + i) = i+1; } while (0); *(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2; pskb_put(skb, trailer, clen - skb->len); top_iph = (struct ipv6hdr *)__skb_push(skb, hdr_len); esph = (struct ipv6_esp_hdr *)skb->h.raw; top_iph->payload_len = htons(skb->len + alen - sizeof(*top_iph)); *(u8*)(trailer->tail - 1) = *skb->nh.raw; *skb->nh.raw = IPPROTO_ESP; esph->spi = x->id.spi; esph->seq_no = htonl(++x->replay.oseq); if (esp->conf.ivlen) crypto_cipher_set_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); do { struct scatterlist *sg = &esp->sgbuf[0]; if (unlikely(nfrags > ESP_NUM_FAST_SG)) { sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); if (!sg) goto error; } skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen); crypto_cipher_encrypt(tfm, sg, sg, clen); if (unlikely(sg != &esp->sgbuf[0])) kfree(sg); } while (0); if (esp->conf.ivlen) { memcpy(esph->enc_data, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); crypto_cipher_get_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); } if (esp->auth.icv_full_len) { esp->auth.icv(esp, skb, (u8*)esph-skb->data, sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen+clen, trailer->tail); pskb_put(skb, trailer, alen); } err = 0; error: return 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. */ int esp_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) { struct iphdr *iph; struct ip_esp_hdr *esph; struct esp_data *esp = x->data; struct sk_buff *trailer; int blksize = crypto_tfm_alg_blocksize(esp->conf.tfm); int alen = esp->auth.icv_trunc_len; int elen = skb->len - sizeof(struct ip_esp_hdr) - esp->conf.ivlen - alen; int nfrags; int encap_len = 0; if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr))) goto out; if (elen <= 0 || (elen & (blksize-1))) goto out; /* If integrity check is required, do this. */ if (esp->auth.icv_full_len) { u8 sum[esp->auth.icv_full_len]; u8 sum1[alen]; esp->auth.icv(esp, skb, 0, skb->len-alen, sum); if (skb_copy_bits(skb, skb->len-alen, sum1, alen)) BUG(); if (unlikely(memcmp(sum, sum1, alen))) { x->stats.integrity_failed++; goto out; } } if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) goto out; skb->ip_summed = CHECKSUM_NONE; esph = (struct ip_esp_hdr*)skb->data; iph = skb->nh.iph; /* Get ivec. This can be wrong, check against another impls. */ if (esp->conf.ivlen) crypto_cipher_set_iv(esp->conf.tfm, esph->enc_data, crypto_tfm_alg_ivsize(esp->conf.tfm)); { u8 nexthdr[2]; struct scatterlist sgbuf[nfrags>MAX_SG_ONSTACK ? 0 : nfrags]; struct scatterlist *sg = sgbuf; u8 workbuf[60]; int padlen; if (unlikely(nfrags > MAX_SG_ONSTACK)) { sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); if (!sg) goto out; } skb_to_sgvec(skb, sg, sizeof(struct ip_esp_hdr) + esp->conf.ivlen, elen); crypto_cipher_decrypt(esp->conf.tfm, sg, sg, elen); if (unlikely(sg != sgbuf)) kfree(sg); if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) BUG(); padlen = nexthdr[0]; if (padlen+2 >= elen) goto out; /* ... check padding bits here. Silly. :-) */ if (x->encap && decap && decap->decap_type) { struct esp_decap_data *encap_data; struct udphdr *uh = (struct udphdr *) (iph+1); encap_data = (struct esp_decap_data *) (decap->decap_data); encap_data->proto = 0; switch (decap->decap_type) { case UDP_ENCAP_ESPINUDP: if ((void*)uh == (void*)esph) { printk(KERN_DEBUG "esp_input(): Got ESP; expecting ESPinUDP\n"); break; } encap_data->proto = AF_INET; encap_data->saddr.a4 = iph->saddr; encap_data->sport = uh->source; encap_len = (void*)esph - (void*)uh; if (encap_len != sizeof(*uh)) printk(KERN_DEBUG "esp_input(): UDP -> ESP: too much room: %d\n", encap_len); break; default: printk(KERN_INFO "esp_input(): processing unknown encap type: %u\n", decap->decap_type); break; } } iph->protocol = nexthdr[1]; pskb_trim(skb, skb->len - alen - padlen - 2); memcpy(workbuf, skb->nh.raw, iph->ihl*4); skb->h.raw = skb_pull(skb, sizeof(struct ip_esp_hdr) + esp->conf.ivlen); skb->nh.raw += encap_len + sizeof(struct ip_esp_hdr) + esp->conf.ivlen; memcpy(skb->nh.raw, workbuf, iph->ihl*4); skb->nh.iph->tot_len = htons(skb->len); } return 0; out: return -EINVAL; }
static int esp6_input(struct xfrm_state *x, struct xfrm_decap_state *decap, struct sk_buff *skb) { struct ipv6hdr *iph; struct ipv6_esp_hdr *esph; struct esp_data *esp = x->data; struct sk_buff *trailer; int blksize = ALIGN(crypto_tfm_alg_blocksize(esp->conf.tfm), 4); int alen = esp->auth.icv_trunc_len; int elen = skb->len - sizeof(struct ipv6_esp_hdr) - esp->conf.ivlen - alen; int hdr_len = skb->h.raw - skb->nh.raw; int nfrags; unsigned char *tmp_hdr = NULL; int ret = 0; if (!pskb_may_pull(skb, sizeof(struct ipv6_esp_hdr))) { ret = -EINVAL; goto out_nofree; } esph = (struct ipv6_esp_hdr*)skb->data; if (elen <= 0 || (elen & (blksize-1))) { ret = -EINVAL; goto out_nofree; } tmp_hdr = kmalloc(hdr_len, GFP_ATOMIC); if (!tmp_hdr) { ret = -ENOMEM; goto out_nofree; } memcpy(tmp_hdr, skb->nh.raw, hdr_len); /* If integrity check is required, do this. */ if (esp->auth.icv_full_len) { u8 sum[esp->auth.icv_full_len]; u8 sum1[alen]; if (x->props.replay_window && xfrm_replay_check(x, esph->seq_no)) { ret = -EINVAL; goto out; } esp->auth.icv(esp, skb, 0, skb->len-alen, sum); if (skb_copy_bits(skb, skb->len-alen, sum1, alen)) BUG(); if (unlikely(memcmp(sum, sum1, alen))) { x->stats.integrity_failed++; ret = -EINVAL; goto out; } if (x->props.replay_window) xfrm_replay_advance(x, esph->seq_no); } if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) { ret = -EINVAL; goto out; } skb->ip_summed = CHECKSUM_NONE; iph = skb->nh.ipv6h; /* Get ivec. This can be wrong, check against another impls. */ if (esp->conf.ivlen) crypto_cipher_set_iv(esp->conf.tfm, esph->enc_data, crypto_tfm_alg_ivsize(esp->conf.tfm)); { u8 nexthdr[2]; struct scatterlist *sg = &esp->sgbuf[0]; u8 padlen; if (unlikely(nfrags > ESP_NUM_FAST_SG)) { sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); if (!sg) { ret = -ENOMEM; goto out; } } skb_to_sgvec(skb, sg, sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen, elen); crypto_cipher_decrypt(esp->conf.tfm, sg, sg, elen); if (unlikely(sg != &esp->sgbuf[0])) kfree(sg); if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) BUG(); padlen = nexthdr[0]; if (padlen+2 >= elen) { LIMIT_NETDEBUG(KERN_WARNING "ipsec esp packet is garbage padlen=%d, elen=%d\n", padlen+2, elen); ret = -EINVAL; goto out; } /* ... check padding bits here. Silly. :-) */ pskb_trim(skb, skb->len - alen - padlen - 2); skb->h.raw = skb_pull(skb, sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen); skb->nh.raw += sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen; memcpy(skb->nh.raw, tmp_hdr, hdr_len); skb->nh.ipv6h->payload_len = htons(skb->len - sizeof(struct ipv6hdr)); ret = nexthdr[1]; } out: kfree(tmp_hdr); out_nofree: return ret; }
static int esp6_init_state(struct xfrm_state *x) { struct esp_data *esp = NULL; /* null auth and encryption can have zero length keys */ if (x->aalg) { if (x->aalg->alg_key_len > 512) goto error; } if (x->ealg == NULL || (x->ealg->alg_key_len == 0 && x->props.ealgo != SADB_EALG_NULL)) goto error; if (x->encap) goto error; esp = kmalloc(sizeof(*esp), GFP_KERNEL); if (esp == NULL) return -ENOMEM; memset(esp, 0, sizeof(*esp)); if (x->aalg) { struct xfrm_algo_desc *aalg_desc; unsigned int digestsize; u32 mode = 0; aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); BUG_ON(!aalg_desc); #ifdef CONFIG_CRYPTO_XCBC mode = aalg_desc->desc.sadb_alg_id == SADB_X_AALG_AES_XCBC_MAC ? CRYPTO_TFM_MODE_CBC : 0; #endif esp->auth.key = x->aalg->alg_key; esp->auth.key_len = (x->aalg->alg_key_len+7)/8; esp->auth.tfm = crypto_alloc_tfm(x->aalg->alg_name, mode); if (esp->auth.tfm == NULL) goto error; #ifdef CONFIG_CRYPTO_XCBC esp->auth.icv = !mode ? esp_hmac_digest : esp_xcbc_digest; #else esp->auth.icv = esp_hmac_digest; #endif digestsize = !mode ? crypto_tfm_alg_digestsize(esp->auth.tfm) : crypto_tfm_alg_blocksize(esp->auth.tfm); if (aalg_desc->uinfo.auth.icv_fullbits/8 != digestsize) { printk(KERN_INFO "ESP: %s digestsize %u != %hu\n", x->aalg->alg_name, digestsize, aalg_desc->uinfo.auth.icv_fullbits/8); goto error; } esp->auth.icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; esp->auth.icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8; esp->auth.work_icv = kmalloc(esp->auth.icv_full_len, GFP_KERNEL); if (!esp->auth.work_icv) goto error; } esp->conf.key = x->ealg->alg_key; if (x->props.ealgo == SADB_EALG_NULL) { esp->conf.key_len = 0; esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_ECB); } else { esp->conf.key_len = (x->ealg->alg_key_len+7)/8; esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_CBC); } if (esp->conf.tfm == NULL) goto error; esp->conf.ivlen = crypto_tfm_alg_ivsize(esp->conf.tfm); esp->conf.padlen = 0; if (esp->conf.ivlen) { esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL); if (unlikely(esp->conf.ivec == NULL)) goto error; get_random_bytes(esp->conf.ivec, esp->conf.ivlen); } if (crypto_cipher_setkey(esp->conf.tfm, esp->conf.key, esp->conf.key_len)) goto error; x->props.header_len = sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen; if (x->props.mode) x->props.header_len += sizeof(struct ipv6hdr); x->data = esp; return 0; error: x->data = esp; esp6_destroy(x); x->data = NULL; return -EINVAL; }
static int esp_output(struct sk_buff *skb) { int err; struct dst_entry *dst = skb->dst; struct xfrm_state *x = dst->xfrm; struct iphdr *top_iph; struct ip_esp_hdr *esph; struct crypto_tfm *tfm; struct esp_data *esp; struct sk_buff *trailer; int blksize; int clen; int alen; int nfrags; /* Strip IP+ESP header. */ __skb_pull(skb, skb->h.raw - skb->data); /* Now skb is pure payload to encrypt */ err = -ENOMEM; /* Round to block size */ clen = skb->len; esp = x->data; alen = esp->auth.icv_trunc_len; tfm = esp->conf.tfm; blksize = (crypto_tfm_alg_blocksize(tfm) + 3) & ~3; clen = (clen + 2 + blksize-1)&~(blksize-1); if (esp->conf.padlen) clen = (clen + esp->conf.padlen-1)&~(esp->conf.padlen-1); if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0) goto error; /* Fill padding... */ do { int i; for (i=0; i<clen-skb->len - 2; i++) *(u8*)(trailer->tail + i) = i+1; } while (0); *(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2; pskb_put(skb, trailer, clen - skb->len); __skb_push(skb, skb->data - skb->nh.raw); top_iph = skb->nh.iph; esph = (struct ip_esp_hdr *)(skb->nh.raw + top_iph->ihl*4); top_iph->tot_len = htons(skb->len + alen); *(u8*)(trailer->tail - 1) = top_iph->protocol; /* this is non-NULL only with UDP Encapsulation */ if (x->encap) { struct xfrm_encap_tmpl *encap = x->encap; struct udphdr *uh; u32 *udpdata32; uh = (struct udphdr *)esph; uh->source = encap->encap_sport; uh->dest = encap->encap_dport; uh->len = htons(skb->len + alen - top_iph->ihl*4); uh->check = 0; switch (encap->encap_type) { default: case UDP_ENCAP_ESPINUDP: esph = (struct ip_esp_hdr *)(uh + 1); break; case UDP_ENCAP_ESPINUDP_NON_IKE: udpdata32 = (u32 *)(uh + 1); udpdata32[0] = udpdata32[1] = 0; esph = (struct ip_esp_hdr *)(udpdata32 + 2); break; } top_iph->protocol = IPPROTO_UDP; } else top_iph->protocol = IPPROTO_ESP; esph->spi = x->id.spi; esph->seq_no = htonl(++x->replay.oseq); if (esp->conf.ivlen) crypto_cipher_set_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); do { struct scatterlist *sg = &esp->sgbuf[0]; if (unlikely(nfrags > ESP_NUM_FAST_SG)) { sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); if (!sg) goto error; } skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen); crypto_cipher_encrypt(tfm, sg, sg, clen); if (unlikely(sg != &esp->sgbuf[0])) kfree(sg); } while (0); if (esp->conf.ivlen) { memcpy(esph->enc_data, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); crypto_cipher_get_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); } if (esp->auth.icv_full_len) { esp->auth.icv(esp, skb, (u8*)esph-skb->data, sizeof(struct ip_esp_hdr) + esp->conf.ivlen+clen, trailer->tail); pskb_put(skb, trailer, alen); } ip_send_check(top_iph); err = 0; error: return 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 xfrm_decap_state *decap, struct sk_buff *skb) { struct iphdr *iph; struct ip_esp_hdr *esph; struct esp_data *esp = x->data; struct sk_buff *trailer; int blksize = ALIGN(crypto_tfm_alg_blocksize(esp->conf.tfm), 4); int alen = esp->auth.icv_trunc_len; int elen = skb->len - sizeof(struct ip_esp_hdr) - esp->conf.ivlen - alen; int nfrags; int encap_len = 0; u8 nexthdr[2]; struct scatterlist *sg; u8 workbuf[60]; int padlen; if (!pskb_may_pull(skb, sizeof(struct ip_esp_hdr))) goto out; esph = (struct ip_esp_hdr*)skb->data; if (elen <= 0 || (elen & (blksize-1))) goto out; /* If integrity check is required, do this. */ if (esp->auth.icv_full_len) { u8 sum[esp->auth.icv_full_len]; u8 sum1[alen]; if (x->props.replay_window && xfrm_replay_check(x, esph->seq_no)) goto out; esp->auth.icv(esp, skb, 0, skb->len-alen, sum); if (skb_copy_bits(skb, skb->len-alen, sum1, alen)) BUG(); if (unlikely(memcmp(sum, sum1, alen))) { x->stats.integrity_failed++; goto out; } if (x->props.replay_window) xfrm_replay_advance(x, esph->seq_no); } if ((nfrags = skb_cow_data(skb, 0, &trailer)) < 0) goto out; skb->ip_summed = CHECKSUM_NONE; iph = skb->nh.iph; /* Get ivec. This can be wrong, check against another impls. */ if (esp->conf.ivlen) crypto_cipher_set_iv(esp->conf.tfm, esph->enc_data, crypto_tfm_alg_ivsize(esp->conf.tfm)); sg = &esp->sgbuf[0]; if (unlikely(nfrags > ESP_NUM_FAST_SG)) { sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); if (!sg) goto out; } skb_to_sgvec(skb, sg, sizeof(struct ip_esp_hdr) + esp->conf.ivlen, elen); crypto_cipher_decrypt(esp->conf.tfm, sg, sg, elen); if (unlikely(sg != &esp->sgbuf[0])) kfree(sg); if (skb_copy_bits(skb, skb->len-alen-2, nexthdr, 2)) BUG(); padlen = nexthdr[0]; if (padlen+2 >= elen) goto out; /* ... check padding bits here. Silly. :-) */ if (x->encap) { struct xfrm_encap_tmpl *encap = x->encap; struct udphdr *uh; if (encap->encap_type != decap->decap_type) goto out; uh = (struct udphdr *)(iph + 1); encap_len = (void*)esph - (void*)uh; /* * 1) if the NAT-T peer's IP or port changed then * advertize the change to the keying daemon. * This is an inbound SA, so just compare * SRC ports. */ if (iph->saddr != x->props.saddr.a4 || uh->source != encap->encap_sport) { xfrm_address_t ipaddr; ipaddr.a4 = iph->saddr; km_new_mapping(x, &ipaddr, uh->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) skb->ip_summed = CHECKSUM_UNNECESSARY; } iph->protocol = nexthdr[1]; pskb_trim(skb, skb->len - alen - padlen - 2); memcpy(workbuf, skb->nh.raw, iph->ihl*4); skb->h.raw = skb_pull(skb, sizeof(struct ip_esp_hdr) + esp->conf.ivlen); skb->nh.raw += encap_len + sizeof(struct ip_esp_hdr) + esp->conf.ivlen; memcpy(skb->nh.raw, workbuf, iph->ihl*4); skb->nh.iph->tot_len = htons(skb->len); return 0; out: return -EINVAL; }
static int esp6_init_state(struct xfrm_state *x) { struct esp_data *esp = NULL; /* null auth and encryption can have zero length keys */ if (x->aalg) { if (x->aalg->alg_key_len > 512) goto error; } if (x->ealg == NULL) goto error; if (x->encap) goto error; esp = kmalloc(sizeof(*esp), GFP_KERNEL); if (esp == NULL) return -ENOMEM; memset(esp, 0, sizeof(*esp)); if (x->aalg) { struct xfrm_algo_desc *aalg_desc; esp->auth.key = x->aalg->alg_key; esp->auth.key_len = (x->aalg->alg_key_len+7)/8; esp->auth.tfm = crypto_alloc_tfm(x->aalg->alg_name, 0); if (esp->auth.tfm == NULL) goto error; esp->auth.icv = esp_hmac_digest; aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name, 0); BUG_ON(!aalg_desc); if (aalg_desc->uinfo.auth.icv_fullbits/8 != crypto_tfm_alg_digestsize(esp->auth.tfm)) { printk(KERN_INFO "ESP: %s digestsize %u != %hu\n", x->aalg->alg_name, crypto_tfm_alg_digestsize(esp->auth.tfm), aalg_desc->uinfo.auth.icv_fullbits/8); goto error; } esp->auth.icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; esp->auth.icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8; esp->auth.work_icv = kmalloc(esp->auth.icv_full_len, GFP_KERNEL); if (!esp->auth.work_icv) goto error; } esp->conf.key = x->ealg->alg_key; esp->conf.key_len = (x->ealg->alg_key_len+7)/8; if (x->props.ealgo == SADB_EALG_NULL) esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_ECB); else esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_CBC); if (esp->conf.tfm == NULL) goto error; esp->conf.ivlen = crypto_tfm_alg_ivsize(esp->conf.tfm); esp->conf.padlen = 0; if (esp->conf.ivlen) { esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL); if (unlikely(esp->conf.ivec == NULL)) goto error; get_random_bytes(esp->conf.ivec, esp->conf.ivlen); } if (crypto_cipher_setkey(esp->conf.tfm, esp->conf.key, esp->conf.key_len)) goto error; x->props.header_len = sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen; if (x->props.mode) x->props.header_len += sizeof(struct ipv6hdr); x->data = esp; #if defined (CONFIG_OCTEON_NATIVE_IPSEC) esp->oct_data = cavium_alloc_n_fill(x); #endif return 0; error: x->data = esp; esp6_destroy(x); x->data = NULL; return -EINVAL; }
int esp6_output(struct sk_buff *skb) { int err; int hdr_len = 0; struct dst_entry *dst = skb->dst; struct xfrm_state *x = dst->xfrm; struct ipv6hdr *iph = NULL, *top_iph; struct ipv6_esp_hdr *esph; struct crypto_tfm *tfm; struct esp_data *esp; struct sk_buff *trailer; int blksize; int clen; int alen; int nfrags; u8 *prevhdr; u8 nexthdr = 0; /* First, if the skb is not checksummed, complete checksum. */ if (skb->ip_summed == CHECKSUM_HW && skb_checksum_help(skb) == NULL) { err = -EINVAL; goto error_nolock; } spin_lock_bh(&x->lock); err = xfrm_check_output(x, skb, AF_INET6); if (err) goto error; err = -ENOMEM; /* Strip IP header in transport mode. Save it. */ if (!x->props.mode) { hdr_len = ip6_find_1stfragopt(skb, &prevhdr); nexthdr = *prevhdr; *prevhdr = IPPROTO_ESP; iph = kmalloc(hdr_len, GFP_ATOMIC); if (!iph) { err = -ENOMEM; goto error; } memcpy(iph, skb->nh.raw, hdr_len); __skb_pull(skb, hdr_len); } /* Now skb is pure payload to encrypt */ /* Round to block size */ clen = skb->len; esp = x->data; alen = esp->auth.icv_trunc_len; tfm = esp->conf.tfm; blksize = (crypto_tfm_alg_blocksize(tfm) + 3) & ~3; clen = (clen + 2 + blksize-1)&~(blksize-1); if (esp->conf.padlen) clen = (clen + esp->conf.padlen-1)&~(esp->conf.padlen-1); if ((nfrags = skb_cow_data(skb, clen-skb->len+alen, &trailer)) < 0) { if (!x->props.mode && iph) kfree(iph); goto error; } /* Fill padding... */ do { int i; for (i=0; i<clen-skb->len - 2; i++) *(u8*)(trailer->tail + i) = i+1; } while (0); *(u8*)(trailer->tail + clen-skb->len - 2) = (clen - skb->len)-2; pskb_put(skb, trailer, clen - skb->len); if (x->props.mode) { iph = skb->nh.ipv6h; top_iph = (struct ipv6hdr*)skb_push(skb, x->props.header_len); esph = (struct ipv6_esp_hdr*)(top_iph+1); *(u8*)(trailer->tail - 1) = IPPROTO_IPV6; top_iph->version = 6; top_iph->priority = iph->priority; top_iph->flow_lbl[0] = iph->flow_lbl[0]; top_iph->flow_lbl[1] = iph->flow_lbl[1]; top_iph->flow_lbl[2] = iph->flow_lbl[2]; if (x->props.flags & XFRM_STATE_NOECN) IP6_ECN_clear(top_iph); top_iph->nexthdr = IPPROTO_ESP; top_iph->payload_len = htons(skb->len + alen - sizeof(struct ipv6hdr)); top_iph->hop_limit = iph->hop_limit; ipv6_addr_copy(&top_iph->saddr, (struct in6_addr *)&x->props.saddr); ipv6_addr_copy(&top_iph->daddr, (struct in6_addr *)&x->id.daddr); } else { esph = (struct ipv6_esp_hdr*)skb_push(skb, x->props.header_len); skb->h.raw = (unsigned char*)esph; top_iph = (struct ipv6hdr*)skb_push(skb, hdr_len); memcpy(top_iph, iph, hdr_len); kfree(iph); top_iph->payload_len = htons(skb->len + alen - sizeof(struct ipv6hdr)); *(u8*)(trailer->tail - 1) = nexthdr; } esph->spi = x->id.spi; esph->seq_no = htonl(++x->replay.oseq); if (esp->conf.ivlen) crypto_cipher_set_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); do { struct scatterlist sgbuf[nfrags>MAX_SG_ONSTACK ? 0 : nfrags]; struct scatterlist *sg = sgbuf; if (unlikely(nfrags > MAX_SG_ONSTACK)) { sg = kmalloc(sizeof(struct scatterlist)*nfrags, GFP_ATOMIC); if (!sg) goto error; } skb_to_sgvec(skb, sg, esph->enc_data+esp->conf.ivlen-skb->data, clen); crypto_cipher_encrypt(tfm, sg, sg, clen); if (unlikely(sg != sgbuf)) kfree(sg); } while (0); if (esp->conf.ivlen) { memcpy(esph->enc_data, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); crypto_cipher_get_iv(tfm, esp->conf.ivec, crypto_tfm_alg_ivsize(tfm)); } if (esp->auth.icv_full_len) { esp->auth.icv(esp, skb, (u8*)esph-skb->data, sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen+clen, trailer->tail); pskb_put(skb, trailer, alen); } skb->nh.raw = skb->data; x->curlft.bytes += skb->len; x->curlft.packets++; spin_unlock_bh(&x->lock); if ((skb->dst = dst_pop(dst)) == NULL) { err = -EHOSTUNREACH; goto error_nolock; } return NET_XMIT_BYPASS; error: spin_unlock_bh(&x->lock); error_nolock: kfree_skb(skb); return err; }
int esp6_init_state(struct xfrm_state *x, void *args) { struct esp_data *esp = NULL; if (x->aalg) { if (x->aalg->alg_key_len == 0 || x->aalg->alg_key_len > 512) goto error; } if (x->ealg == NULL) goto error; esp = kmalloc(sizeof(*esp), GFP_KERNEL); if (esp == NULL) return -ENOMEM; memset(esp, 0, sizeof(*esp)); if (x->aalg) { struct xfrm_algo_desc *aalg_desc; esp->auth.key = x->aalg->alg_key; esp->auth.key_len = (x->aalg->alg_key_len+7)/8; esp->auth.tfm = crypto_alloc_tfm(x->aalg->alg_name, 0); if (esp->auth.tfm == NULL) goto error; esp->auth.icv = esp_hmac_digest; aalg_desc = xfrm_aalg_get_byname(x->aalg->alg_name); BUG_ON(!aalg_desc); if (aalg_desc->uinfo.auth.icv_fullbits/8 != crypto_tfm_alg_digestsize(esp->auth.tfm)) { printk(KERN_INFO "ESP: %s digestsize %u != %hu\n", x->aalg->alg_name, crypto_tfm_alg_digestsize(esp->auth.tfm), aalg_desc->uinfo.auth.icv_fullbits/8); goto error; } esp->auth.icv_full_len = aalg_desc->uinfo.auth.icv_fullbits/8; esp->auth.icv_trunc_len = aalg_desc->uinfo.auth.icv_truncbits/8; esp->auth.work_icv = kmalloc(esp->auth.icv_full_len, GFP_KERNEL); if (!esp->auth.work_icv) goto error; } esp->conf.key = x->ealg->alg_key; esp->conf.key_len = (x->ealg->alg_key_len+7)/8; if (x->props.ealgo == SADB_EALG_NULL) esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_ECB); else esp->conf.tfm = crypto_alloc_tfm(x->ealg->alg_name, CRYPTO_TFM_MODE_CBC); if (esp->conf.tfm == NULL) goto error; esp->conf.ivlen = crypto_tfm_alg_ivsize(esp->conf.tfm); esp->conf.padlen = 0; if (esp->conf.ivlen) { esp->conf.ivec = kmalloc(esp->conf.ivlen, GFP_KERNEL); get_random_bytes(esp->conf.ivec, esp->conf.ivlen); } crypto_cipher_setkey(esp->conf.tfm, esp->conf.key, esp->conf.key_len); x->props.header_len = sizeof(struct ipv6_esp_hdr) + esp->conf.ivlen; if (x->props.mode) x->props.header_len += sizeof(struct ipv6hdr); x->data = esp; return 0; error: if (esp) { if (esp->auth.tfm) crypto_free_tfm(esp->auth.tfm); if (esp->auth.work_icv) kfree(esp->auth.work_icv); if (esp->conf.tfm) crypto_free_tfm(esp->conf.tfm); kfree(esp); } return -EINVAL; }