[PATCH v3 1/4] ipsec: add AES-CTR algorithm support

[Fan Zhang <roy.fan.zhang@intel.com>]

This patch adds AES-CTR cipher algorithm support to ipsec
library.

Signed-off-by: Fan Zhang <roy.fan.zhang@intel.com>
---
 lib/librte_ipsec/crypto.h |  17 ++++++
 lib/librte_ipsec/sa.c     | 133 ++++++++++++++++++++++++++++++++++++++--------
 lib/librte_ipsec/sa.h     |  18 +++++++
 3 files changed, 147 insertions(+), 21 deletions(-)

diff --git a/lib/librte_ipsec/crypto.h b/lib/librte_ipsec/crypto.h
index b5f264831..4f551e39c 100644
--- a/lib/librte_ipsec/crypto.h
+++ b/lib/librte_ipsec/crypto.h
@@ -11,6 +11,16 @@
  * by ipsec library.
  */
 
+/*
+ * AES-CTR counter block format.
+ */
+
+struct aesctr_cnt_blk {
+	uint32_t nonce;
+	uint64_t iv;
+	uint32_t cnt;
+} __attribute__((packed));
+
  /*
   * AES-GCM devices have some specific requirements for IV and AAD formats.
   * Ideally that to be done by the driver itself.
@@ -41,6 +51,13 @@ struct gcm_esph_iv {
 	uint64_t iv;
 } __attribute__((packed));
 
+static inline void
+aes_ctr_cnt_blk_fill(struct aesctr_cnt_blk *ctr, uint64_t iv, uint32_t nonce)
+{
+	ctr->nonce = nonce;
+	ctr->iv = iv;
+	ctr->cnt = rte_cpu_to_be_32(1);
+}
 
 static inline void
 aead_gcm_iv_fill(struct aead_gcm_iv *gcm, uint64_t iv, uint32_t salt)
diff --git a/lib/librte_ipsec/sa.c b/lib/librte_ipsec/sa.c
index 5f55c2a4e..e34dd320a 100644
--- a/lib/librte_ipsec/sa.c
+++ b/lib/librte_ipsec/sa.c
@@ -219,18 +219,28 @@ esp_inb_tun_init(struct rte_ipsec_sa *sa, const struct rte_ipsec_sa_prm *prm)
 static void
 esp_outb_init(struct rte_ipsec_sa *sa, uint32_t hlen)
 {
+	uint8_t algo_type;
+
 	sa->sqn.outb.raw = 1;
 
 	/* these params may differ with new algorithms support */
 	sa->ctp.auth.offset = hlen;
 	sa->ctp.auth.length = sizeof(struct esp_hdr) + sa->iv_len + sa->sqh_len;
-	if (sa->aad_len != 0) {
+
+	algo_type = sa->algo_type;
+
+	switch (algo_type) {
+	case ALGO_TYPE_AES_GCM:
+	case ALGO_TYPE_AES_CTR:
+	case ALGO_TYPE_NULL:
 		sa->ctp.cipher.offset = hlen + sizeof(struct esp_hdr) +
 			sa->iv_len;
 		sa->ctp.cipher.length = 0;
-	} else {
+		break;
+	case ALGO_TYPE_AES_CBC:
 		sa->ctp.cipher.offset = sa->hdr_len + sizeof(struct esp_hdr);
 		sa->ctp.cipher.length = sa->iv_len;
+		break;
 	}
 }
 
@@ -259,26 +269,47 @@ esp_sa_init(struct rte_ipsec_sa *sa, const struct rte_ipsec_sa_prm *prm,
 				RTE_IPSEC_SATP_MODE_MASK;
 
 	if (cxf->aead != NULL) {
-		/* RFC 4106 */
-		if (cxf->aead->algo != RTE_CRYPTO_AEAD_AES_GCM)
+		switch (cxf->aead->algo) {
+		case RTE_CRYPTO_AEAD_AES_GCM:
+			/* RFC 4106 */
+			sa->aad_len = sizeof(struct aead_gcm_aad);
+			sa->icv_len = cxf->aead->digest_length;
+			sa->iv_ofs = cxf->aead->iv.offset;
+			sa->iv_len = sizeof(uint64_t);
+			sa->pad_align = IPSEC_PAD_AES_GCM;
+			sa->algo_type = ALGO_TYPE_AES_GCM;
+			break;
+		default:
 			return -EINVAL;
-		sa->aad_len = sizeof(struct aead_gcm_aad);
-		sa->icv_len = cxf->aead->digest_length;
-		sa->iv_ofs = cxf->aead->iv.offset;
-		sa->iv_len = sizeof(uint64_t);
-		sa->pad_align = IPSEC_PAD_AES_GCM;
+		}
 	} else {
 		sa->icv_len = cxf->auth->digest_length;
 		sa->iv_ofs = cxf->cipher->iv.offset;
 		sa->sqh_len = IS_ESN(sa) ? sizeof(uint32_t) : 0;
-		if (cxf->cipher->algo == RTE_CRYPTO_CIPHER_NULL) {
+
+		switch (cxf->cipher->algo) {
+		case RTE_CRYPTO_CIPHER_NULL:
 			sa->pad_align = IPSEC_PAD_NULL;
 			sa->iv_len = 0;
-		} else if (cxf->cipher->algo == RTE_CRYPTO_CIPHER_AES_CBC) {
+			sa->algo_type = ALGO_TYPE_NULL;
+			break;
+
+		case RTE_CRYPTO_CIPHER_AES_CBC:
 			sa->pad_align = IPSEC_PAD_AES_CBC;
 			sa->iv_len = IPSEC_MAX_IV_SIZE;
-		} else
+			sa->algo_type = ALGO_TYPE_AES_CBC;
+			break;
+
+		case RTE_CRYPTO_CIPHER_AES_CTR:
+			/* RFC 3686 */
+			sa->pad_align = IPSEC_PAD_AES_CTR;
+			sa->iv_len = IPSEC_AES_CTR_IV_SIZE;
+			sa->algo_type = ALGO_TYPE_AES_CTR;
+			break;
+
+		default:
 			return -EINVAL;
+		}
 	}
 
 	sa->udata = prm->userdata;
@@ -438,12 +469,15 @@ esp_outb_cop_prepare(struct rte_crypto_op *cop,
 {
 	struct rte_crypto_sym_op *sop;
 	struct aead_gcm_iv *gcm;
+	struct aesctr_cnt_blk *ctr;
+	uint8_t algo_type = sa->algo_type;
 
 	/* fill sym op fields */
 	sop = cop->sym;
 
-	/* AEAD (AES_GCM) case */
-	if (sa->aad_len != 0) {
+	switch (algo_type) {
+	case ALGO_TYPE_AES_GCM:
+		/* AEAD (AES_GCM) case */
 		sop->aead.data.offset = sa->ctp.cipher.offset + hlen;
 		sop->aead.data.length = sa->ctp.cipher.length + plen;
 		sop->aead.digest.data = icv->va;
@@ -455,14 +489,40 @@ esp_outb_cop_prepare(struct rte_crypto_op *cop,
 		gcm = rte_crypto_op_ctod_offset(cop, struct aead_gcm_iv *,
 			sa->iv_ofs);
 		aead_gcm_iv_fill(gcm, ivp[0], sa->salt);
-	/* CRYPT+AUTH case */
-	} else {
+		break;
+	case ALGO_TYPE_AES_CBC:
+		/* Cipher-Auth (AES-CBC *) case */
+		sop->cipher.data.offset = sa->ctp.cipher.offset + hlen;
+		sop->cipher.data.length = sa->ctp.cipher.length + plen;
+		sop->auth.data.offset = sa->ctp.auth.offset + hlen;
+		sop->auth.data.length = sa->ctp.auth.length + plen;
+		sop->auth.digest.data = icv->va;
+		sop->auth.digest.phys_addr = icv->pa;
+		break;
+	case ALGO_TYPE_AES_CTR:
+		/* Cipher-Auth (AES-CTR *) case */
+		sop->cipher.data.offset = sa->ctp.cipher.offset + hlen;
+		sop->cipher.data.length = sa->ctp.cipher.length + plen;
+		sop->auth.data.offset = sa->ctp.auth.offset + hlen;
+		sop->auth.data.length = sa->ctp.auth.length + plen;
+		sop->auth.digest.data = icv->va;
+		sop->auth.digest.phys_addr = icv->pa;
+
+		ctr = rte_crypto_op_ctod_offset(cop, struct aesctr_cnt_blk *,
+			sa->iv_ofs);
+		aes_ctr_cnt_blk_fill(ctr, ivp[0], sa->salt);
+		break;
+	case ALGO_TYPE_NULL:
+		/* NULL case */
 		sop->cipher.data.offset = sa->ctp.cipher.offset + hlen;
 		sop->cipher.data.length = sa->ctp.cipher.length + plen;
 		sop->auth.data.offset = sa->ctp.auth.offset + hlen;
 		sop->auth.data.length = sa->ctp.auth.length + plen;
 		sop->auth.digest.data = icv->va;
 		sop->auth.digest.phys_addr = icv->pa;
+		break;
+	default:
+		break;
 	}
 }
 
@@ -561,6 +621,7 @@ outb_pkt_xprepare(const struct rte_ipsec_sa *sa, rte_be64_t sqc,
 {
 	uint32_t *psqh;
 	struct aead_gcm_aad *aad;
+	uint8_t algo_type = sa->algo_type;
 
 	/* insert SQN.hi between ESP trailer and ICV */
 	if (sa->sqh_len != 0) {
@@ -572,7 +633,7 @@ outb_pkt_xprepare(const struct rte_ipsec_sa *sa, rte_be64_t sqc,
 	 * fill IV and AAD fields, if any (aad fields are placed after icv),
 	 * right now we support only one AEAD algorithm: AES-GCM .
 	 */
-	if (sa->aad_len != 0) {
+	if (algo_type == ALGO_TYPE_AES_GCM) {
 		aad = (struct aead_gcm_aad *)(icv->va + sa->icv_len);
 		aead_gcm_aad_fill(aad, sa->spi, sqc, IS_ESN(sa));
 	}
@@ -783,8 +844,10 @@ esp_inb_tun_cop_prepare(struct rte_crypto_op *cop,
 {
 	struct rte_crypto_sym_op *sop;
 	struct aead_gcm_iv *gcm;
+	struct aesctr_cnt_blk *ctr;
 	uint64_t *ivc, *ivp;
 	uint32_t clen;
+	uint8_t algo_type = sa->algo_type;
 
 	clen = plen - sa->ctp.cipher.length;
 	if ((int32_t)clen < 0 || (clen & (sa->pad_align - 1)) != 0)
@@ -793,8 +856,8 @@ esp_inb_tun_cop_prepare(struct rte_crypto_op *cop,
 	/* fill sym op fields */
 	sop = cop->sym;
 
-	/* AEAD (AES_GCM) case */
-	if (sa->aad_len != 0) {
+	switch (algo_type) {
+	case ALGO_TYPE_AES_GCM:
 		sop->aead.data.offset = pofs + sa->ctp.cipher.offset;
 		sop->aead.data.length = clen;
 		sop->aead.digest.data = icv->va;
@@ -808,8 +871,8 @@ esp_inb_tun_cop_prepare(struct rte_crypto_op *cop,
 		ivp = rte_pktmbuf_mtod_offset(mb, uint64_t *,
 			pofs + sizeof(struct esp_hdr));
 		aead_gcm_iv_fill(gcm, ivp[0], sa->salt);
-	/* CRYPT+AUTH case */
-	} else {
+		break;
+	case ALGO_TYPE_AES_CBC:
 		sop->cipher.data.offset = pofs + sa->ctp.cipher.offset;
 		sop->cipher.data.length = clen;
 		sop->auth.data.offset = pofs + sa->ctp.auth.offset;
@@ -822,7 +885,35 @@ esp_inb_tun_cop_prepare(struct rte_crypto_op *cop,
 		ivp = rte_pktmbuf_mtod_offset(mb, uint64_t *,
 			pofs + sizeof(struct esp_hdr));
 		copy_iv(ivc, ivp, sa->iv_len);
+		break;
+	case ALGO_TYPE_AES_CTR:
+		sop->cipher.data.offset = pofs + sa->ctp.cipher.offset;
+		sop->cipher.data.length = clen;
+		sop->auth.data.offset = pofs + sa->ctp.auth.offset;
+		sop->auth.data.length = plen - sa->ctp.auth.length;
+		sop->auth.digest.data = icv->va;
+		sop->auth.digest.phys_addr = icv->pa;
+
+		/* copy iv from the input packet to the cop */
+		ctr = rte_crypto_op_ctod_offset(cop, struct aesctr_cnt_blk *,
+			sa->iv_ofs);
+		ivp = rte_pktmbuf_mtod_offset(mb, uint64_t *,
+			pofs + sizeof(struct esp_hdr));
+		aes_ctr_cnt_blk_fill(ctr, ivp[0], sa->salt);
+		break;
+	case ALGO_TYPE_NULL:
+		sop->cipher.data.offset = pofs + sa->ctp.cipher.offset;
+		sop->cipher.data.length = clen;
+		sop->auth.data.offset = pofs + sa->ctp.auth.offset;
+		sop->auth.data.length = plen - sa->ctp.auth.length;
+		sop->auth.digest.data = icv->va;
+		sop->auth.digest.phys_addr = icv->pa;
+		break;
+
+	default:
+		return -EINVAL;
 	}
+
 	return 0;
 }
 
diff --git a/lib/librte_ipsec/sa.h b/lib/librte_ipsec/sa.h
index 392e8fd7b..12c061ee6 100644
--- a/lib/librte_ipsec/sa.h
+++ b/lib/librte_ipsec/sa.h
@@ -15,10 +15,17 @@
 enum {
 	IPSEC_PAD_DEFAULT = 4,
 	IPSEC_PAD_AES_CBC = IPSEC_MAX_IV_SIZE,
+	IPSEC_PAD_AES_CTR = IPSEC_PAD_DEFAULT,
 	IPSEC_PAD_AES_GCM = IPSEC_PAD_DEFAULT,
 	IPSEC_PAD_NULL = IPSEC_PAD_DEFAULT,
 };
 
+/* iv sizes for different algorithms */
+enum {
+	IPSEC_IV_SIZE_DEFAULT = IPSEC_MAX_IV_SIZE,
+	IPSEC_AES_CTR_IV_SIZE = sizeof(uint64_t),
+};
+
 /* these definitions probably has to be in rte_crypto_sym.h */
 union sym_op_ofslen {
 	uint64_t raw;
@@ -47,7 +54,17 @@ struct replay_sqn {
 	__extension__ uint64_t window[0];
 };
 
+/*IPSEC SA supported algorithms */
+enum sa_algo_type	{
+	ALGO_TYPE_NULL = 0,
+	ALGO_TYPE_AES_CBC,
+	ALGO_TYPE_AES_CTR,
+	ALGO_TYPE_AES_GCM,
+	ALGO_TYPE_MAX
+};
+
 struct rte_ipsec_sa {
+
 	uint64_t type;     /* type of given SA */
 	uint64_t udata;    /* user defined */
 	uint32_t size;     /* size of given sa object */
@@ -65,6 +82,7 @@ struct rte_ipsec_sa {
 		union sym_op_ofslen auth;
 	} ctp;
 	uint32_t salt;
+	uint8_t algo_type;
 	uint8_t proto;    /* next proto */
 	uint8_t aad_len;
 	uint8_t hdr_len;
-- 
2.14.5