From 7021b2e1cddd318fd07259606b7ecd912a152c09 Mon Sep 17 00:00:00 2001 From: Herbert Xu Date: Wed, 27 May 2015 16:03:46 +0800 Subject: [PATCH] esp4: Switch to new AEAD interface This patch makes use of the new AEAD interface which uses a single SG list instead of separate lists for the AD and plain text. The IV generation is also now carried out through normal AEAD methods. Signed-off-by: Herbert Xu --- net/ipv4/esp4.c | 198 +++++++++++++++++++++++++++++------------------- 1 file changed, 121 insertions(+), 77 deletions(-) diff --git a/net/ipv4/esp4.c b/net/ipv4/esp4.c index 421a80b09b62..477937465a20 100644 --- a/net/ipv4/esp4.c +++ b/net/ipv4/esp4.c @@ -49,7 +49,7 @@ static void *esp_alloc_tmp(struct crypto_aead *aead, int nfrags, int seqhilen) len = ALIGN(len, crypto_tfm_ctx_alignment()); } - len += sizeof(struct aead_givcrypt_request) + crypto_aead_reqsize(aead); + len += sizeof(struct aead_request) + crypto_aead_reqsize(aead); len = ALIGN(len, __alignof__(struct scatterlist)); len += sizeof(struct scatterlist) * nfrags; @@ -68,17 +68,6 @@ static inline u8 *esp_tmp_iv(struct crypto_aead *aead, void *tmp, int seqhilen) crypto_aead_alignmask(aead) + 1) : tmp + seqhilen; } -static inline struct aead_givcrypt_request *esp_tmp_givreq( - struct crypto_aead *aead, u8 *iv) -{ - struct aead_givcrypt_request *req; - - req = (void *)PTR_ALIGN(iv + crypto_aead_ivsize(aead), - crypto_tfm_ctx_alignment()); - aead_givcrypt_set_tfm(req, aead); - return req; -} - static inline struct aead_request *esp_tmp_req(struct crypto_aead *aead, u8 *iv) { struct aead_request *req; @@ -97,14 +86,6 @@ static inline struct scatterlist *esp_req_sg(struct crypto_aead *aead, __alignof__(struct scatterlist)); } -static inline struct scatterlist *esp_givreq_sg( - struct crypto_aead *aead, struct aead_givcrypt_request *req) -{ - return (void *)ALIGN((unsigned long)(req + 1) + - crypto_aead_reqsize(aead), - __alignof__(struct scatterlist)); -} - static void esp_output_done(struct crypto_async_request *base, int err) { struct sk_buff *skb = base->data; @@ -113,14 +94,37 @@ static void esp_output_done(struct crypto_async_request *base, int err) xfrm_output_resume(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_seqhi(tmp); + + esph->seq_no = esph->spi; + esph->spi = *seqhi; +} + +static void esp_output_restore_header(struct sk_buff *skb) +{ + esp_restore_header(skb, skb_transport_offset(skb) - sizeof(__be32)); +} + +static void esp_output_done_esn(struct crypto_async_request *base, int err) +{ + struct sk_buff *skb = base->data; + + esp_output_restore_header(skb); + esp_output_done(base, err); +} + static int esp_output(struct xfrm_state *x, struct sk_buff *skb) { int err; struct ip_esp_hdr *esph; struct crypto_aead *aead; - struct aead_givcrypt_request *req; + struct aead_request *req; struct scatterlist *sg; - struct scatterlist *asg; struct sk_buff *trailer; void *tmp; u8 *iv; @@ -129,17 +133,19 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) int clen; int alen; int plen; + int ivlen; int tfclen; int nfrags; int assoclen; - int sglists; int seqhilen; __be32 *seqhi; + __be64 seqno; /* skb is pure payload to encrypt */ aead = x->data; alen = crypto_aead_authsize(aead); + ivlen = crypto_aead_ivsize(aead); tfclen = 0; if (x->tfcpad) { @@ -160,16 +166,14 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) nfrags = err; 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); + tmp = esp_alloc_tmp(aead, nfrags, seqhilen); if (!tmp) { err = -ENOMEM; goto error; @@ -177,9 +181,8 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) 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 + sglists; + req = esp_tmp_req(aead, iv); + sg = esp_req_sg(aead, req); /* Fill padding... */ tail = skb_tail_pointer(trailer); @@ -235,36 +238,53 @@ static int esp_output(struct xfrm_state *x, struct sk_buff *skb) *skb_mac_header(skb) = IPPROTO_UDP; } - esph->spi = x->id.spi; esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.low); + aead_request_set_callback(req, 0, esp_output_done, skb); + + /* For ESN we move the header forward by 4 bytes to + * accomodate the high bits. We will move it back after + * encryption. + */ + if ((x->props.flags & XFRM_STATE_ESN)) { + esph = (void *)(skb_transport_header(skb) - sizeof(__be32)); + *seqhi = esph->spi; + esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.output.hi); + aead_request_set_callback(req, 0, esp_output_done_esn, skb); + } + + esph->spi = x->id.spi; + sg_init_table(sg, nfrags); skb_to_sgvec(skb, sg, - esph->enc_data + crypto_aead_ivsize(aead) - skb->data, - clen + alen); + (unsigned char *)esph - skb->data, + assoclen + ivlen + clen + alen); - 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_request_set_crypt(req, sg, sg, ivlen + clen, iv); + aead_request_set_ad(req, assoclen); - 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, assoclen); - aead_givcrypt_set_giv(req, esph->enc_data, - XFRM_SKB_CB(skb)->seq.output.low); + seqno = cpu_to_be64(XFRM_SKB_CB(skb)->seq.output.low + + ((u64)XFRM_SKB_CB(skb)->seq.output.hi << 32)); + + memset(iv, 0, ivlen); + memcpy(iv + ivlen - min(ivlen, 8), (u8 *)&seqno + 8 - min(ivlen, 8), + min(ivlen, 8)); ESP_SKB_CB(skb)->tmp = tmp; - err = crypto_aead_givencrypt(req); - if (err == -EINPROGRESS) + err = crypto_aead_encrypt(req); + + switch (err) { + case -EINPROGRESS: goto error; - if (err == -EBUSY) + case -EBUSY: err = NET_XMIT_DROP; + break; + + case 0: + if ((x->props.flags & XFRM_STATE_ESN)) + esp_output_restore_header(skb); + } kfree(tmp); @@ -363,6 +383,20 @@ static void esp_input_done(struct crypto_async_request *base, int err) 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_done_esn(struct crypto_async_request *base, int err) +{ + struct sk_buff *skb = base->data; + + esp_input_restore_header(skb); + esp_input_done(base, err); +} + /* * Note: detecting truncated vs. non-truncated authentication data is very * expensive, so we only support truncated data, which is the recommended @@ -374,19 +408,18 @@ 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 elen = skb->len - sizeof(*esph) - crypto_aead_ivsize(aead); + int ivlen = crypto_aead_ivsize(aead); + int elen = skb->len - sizeof(*esph) - ivlen; int nfrags; int assoclen; - int sglists; int seqhilen; __be32 *seqhi; void *tmp; u8 *iv; struct scatterlist *sg; - struct scatterlist *asg; int err = -EINVAL; - if (!pskb_may_pull(skb, sizeof(*esph) + crypto_aead_ivsize(aead))) + if (!pskb_may_pull(skb, sizeof(*esph) + ivlen)) goto out; if (elen <= 0) @@ -399,17 +432,15 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) 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 + sglists, seqhilen); + tmp = esp_alloc_tmp(aead, nfrags, seqhilen); if (!tmp) goto out; @@ -417,36 +448,39 @@ static int esp_input(struct xfrm_state *x, struct sk_buff *skb) 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 + sglists; + sg = esp_req_sg(aead, req); skb->ip_summed = CHECKSUM_NONE; esph = (struct ip_esp_hdr *)skb->data; - /* Get ivec. This can be wrong, check against another impls. */ - iv = esph->enc_data; + aead_request_set_callback(req, 0, esp_input_done, skb); + + /* For ESN we move the header forward by 4 bytes to + * accomodate the high bits. We will move it back after + * decryption. + */ + if ((x->props.flags & XFRM_STATE_ESN)) { + esph = (void *)skb_push(skb, 4); + *seqhi = esph->spi; + esph->spi = esph->seq_no; + esph->seq_no = htonl(XFRM_SKB_CB(skb)->seq.input.hi); + aead_request_set_callback(req, 0, esp_input_done_esn, skb); + } sg_init_table(sg, nfrags); - skb_to_sgvec(skb, sg, sizeof(*esph) + crypto_aead_ivsize(aead), elen); + skb_to_sgvec(skb, sg, 0, skb->len); - 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, assoclen); + 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: @@ -518,10 +552,16 @@ static void esp_destroy(struct xfrm_state *x) static int esp_init_aead(struct xfrm_state *x) { + char aead_name[CRYPTO_MAX_ALG_NAME]; struct crypto_aead *aead; int err; - aead = crypto_alloc_aead(x->aead->alg_name, 0, 0); + err = -ENAMETOOLONG; + if (snprintf(aead_name, CRYPTO_MAX_ALG_NAME, "%s(%s)", + x->geniv, x->aead->alg_name) >= CRYPTO_MAX_ALG_NAME) + goto error; + + aead = crypto_alloc_aead(aead_name, 0, 0); err = PTR_ERR(aead); if (IS_ERR(aead)) goto error; @@ -560,15 +600,19 @@ static int esp_init_authenc(struct xfrm_state *x) if ((x->props.flags & XFRM_STATE_ESN)) { if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, - "authencesn(%s,%s)", + "%s%sauthencesn(%s,%s)%s", + x->geniv ?: "", x->geniv ? "(" : "", x->aalg ? x->aalg->alg_name : "digest_null", - x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) + x->ealg->alg_name, + x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) goto error; } else { if (snprintf(authenc_name, CRYPTO_MAX_ALG_NAME, - "authenc(%s,%s)", + "%s%sauthenc(%s,%s)%s", + x->geniv ?: "", x->geniv ? "(" : "", x->aalg ? x->aalg->alg_name : "digest_null", - x->ealg->alg_name) >= CRYPTO_MAX_ALG_NAME) + x->ealg->alg_name, + x->geniv ? ")" : "") >= CRYPTO_MAX_ALG_NAME) goto error; }