[v3,5/9] ipsec: add SA data-path API

diff --git a/lib/librte_ipsec/Makefile b/lib/librte_ipsec/Makefile
index 7758dcc6d..79f187fae 100644
--- a/lib/librte_ipsec/Makefile
+++ b/lib/librte_ipsec/Makefile
@@ -17,8 +17,10 @@  LIBABIVER := 1
 
 # all source are stored in SRCS-y
 SRCS-$(CONFIG_RTE_LIBRTE_IPSEC) += sa.c
+SRCS-$(CONFIG_RTE_LIBRTE_IPSEC) += ses.c
 
 # install header files
+SYMLINK-$(CONFIG_RTE_LIBRTE_IPSEC)-include += rte_ipsec.h
 SYMLINK-$(CONFIG_RTE_LIBRTE_IPSEC)-include += rte_ipsec_sa.h
 
 include $(RTE_SDK)/mk/rte.lib.mk
diff --git a/lib/librte_ipsec/meson.build b/lib/librte_ipsec/meson.build
index 52c78eaeb..6e8c6fabe 100644
--- a/lib/librte_ipsec/meson.build
+++ b/lib/librte_ipsec/meson.build
@@ -3,8 +3,8 @@ 
 
 allow_experimental_apis = true
 
-sources=files('sa.c')
+sources=files('sa.c', 'ses.c')
 
-install_headers = files('rte_ipsec_sa.h')
+install_headers = files('rte_ipsec.h', 'rte_ipsec_sa.h')
 
 deps += ['mbuf', 'net', 'cryptodev', 'security']
diff --git a/lib/librte_ipsec/rte_ipsec.h b/lib/librte_ipsec/rte_ipsec.h
new file mode 100644
index 000000000..429d4bf38
--- /dev/null
+++ b/lib/librte_ipsec/rte_ipsec.h
@@ -0,0 +1,154 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2018 Intel Corporation
+ */
+
+#ifndef _RTE_IPSEC_H_
+#define _RTE_IPSEC_H_
+
+/**
+ * @file rte_ipsec.h
+ * @b EXPERIMENTAL: this API may change without prior notice
+ *
+ * RTE IPsec support.
+ * librte_ipsec provides a framework for data-path IPsec protocol
+ * processing (ESP/AH).
+ * IKEv2 protocol support right now is out of scope of that draft.
+ * Though it tries to define related API in such way, that it could be adopted
+ * by IKEv2 implementation.
+ */
+
+#include <rte_ipsec_sa.h>
+#include <rte_mbuf.h>
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+struct rte_ipsec_session;
+
+/**
+ * IPsec session specific functions that will be used to:
+ * - prepare - for input mbufs and given IPsec session prepare crypto ops
+ *   that can be enqueued into the cryptodev associated with given session
+ *   (see *rte_ipsec_pkt_crypto_prepare* below for more details).
+ * - process - finalize processing of packets after crypto-dev finished
+ *   with them or process packets that are subjects to inline IPsec offload
+ *   (see rte_ipsec_pkt_process for more details).
+ */
+struct rte_ipsec_sa_pkt_func {
+	uint16_t (*prepare)(const struct rte_ipsec_session *ss,
+				struct rte_mbuf *mb[],
+				struct rte_crypto_op *cop[],
+				uint16_t num);
+	uint16_t (*process)(const struct rte_ipsec_session *ss,
+				struct rte_mbuf *mb[],
+				uint16_t num);
+};
+
+/**
+ * rte_ipsec_session is an aggregate structure that defines particular
+ * IPsec Security Association IPsec (SA) on given security/crypto device:
+ * - pointer to the SA object
+ * - security session action type
+ * - pointer to security/crypto session, plus other related data
+ * - session/device specific functions to prepare/process IPsec packets.
+ */
+struct rte_ipsec_session {
+
+	/**
+	 * SA that session belongs to.
+	 * Note that multiple sessions can belong to the same SA.
+	 */
+	struct rte_ipsec_sa *sa;
+	/** session action type */
+	enum rte_security_session_action_type type;
+	/** session and related data */
+	union {
+		struct {
+			struct rte_cryptodev_sym_session *ses;
+		} crypto;
+		struct {
+			struct rte_security_session *ses;
+			struct rte_security_ctx *ctx;
+			uint32_t ol_flags;
+		} security;
+	};
+	/** functions to prepare/process IPsec packets */
+	struct rte_ipsec_sa_pkt_func pkt_func;
+} __rte_cache_aligned;
+
+/**
+ * Checks that inside given rte_ipsec_session crypto/security fields
+ * are filled correctly and setups function pointers based on these values.
+ * @param ss
+ *   Pointer to the *rte_ipsec_session* object
+ * @return
+ *   - Zero if operation completed successfully.
+ *   - -EINVAL if the parameters are invalid.
+ */
+int __rte_experimental
+rte_ipsec_session_prepare(struct rte_ipsec_session *ss);
+
+/**
+ * For input mbufs and given IPsec session prepare crypto ops that can be
+ * enqueued into the cryptodev associated with given session.
+ * expects that for each input packet:
+ *      - l2_len, l3_len are setup correctly
+ * Note that erroneous mbufs are not freed by the function,
+ * but are placed beyond last valid mbuf in the *mb* array.
+ * It is a user responsibility to handle them further.
+ * @param ss
+ *   Pointer to the *rte_ipsec_session* object the packets belong to.
+ * @param mb
+ *   The address of an array of *num* pointers to *rte_mbuf* structures
+ *   which contain the input packets.
+ * @param cop
+ *   The address of an array of *num* pointers to the output *rte_crypto_op*
+ *   structures.
+ * @param num
+ *   The maximum number of packets to process.
+ * @return
+ *   Number of successfully processed packets, with error code set in rte_errno.
+ */
+static inline uint16_t __rte_experimental
+rte_ipsec_pkt_crypto_prepare(const struct rte_ipsec_session *ss,
+	struct rte_mbuf *mb[], struct rte_crypto_op *cop[], uint16_t num)
+{
+	return ss->pkt_func.prepare(ss, mb, cop, num);
+}
+
+/**
+ * Finalise processing of packets after crypto-dev finished with them or
+ * process packets that are subjects to inline IPsec offload.
+ * Expects that for each input packet:
+ *      - l2_len, l3_len are setup correctly
+ * Output mbufs will be:
+ * inbound - decrypted & authenticated, ESP(AH) related headers removed,
+ * *l2_len* and *l3_len* fields are updated.
+ * outbound - appropriate mbuf fields (ol_flags, tx_offloads, etc.)
+ * properly setup, if necessary - IP headers updated, ESP(AH) fields added,
+ * Note that erroneous mbufs are not freed by the function,
+ * but are placed beyond last valid mbuf in the *mb* array.
+ * It is a user responsibility to handle them further.
+ * @param ss
+ *   Pointer to the *rte_ipsec_session* object the packets belong to.
+ * @param mb
+ *   The address of an array of *num* pointers to *rte_mbuf* structures
+ *   which contain the input packets.
+ * @param num
+ *   The maximum number of packets to process.
+ * @return
+ *   Number of successfully processed packets, with error code set in rte_errno.
+ */
+static inline uint16_t __rte_experimental
+rte_ipsec_pkt_process(const struct rte_ipsec_session *ss, struct rte_mbuf *mb[],
+	uint16_t num)
+{
+	return ss->pkt_func.process(ss, mb, num);
+}
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif /* _RTE_IPSEC_H_ */
diff --git a/lib/librte_ipsec/rte_ipsec_version.map b/lib/librte_ipsec/rte_ipsec_version.map
index 1a66726b8..d1c52d7ca 100644
--- a/lib/librte_ipsec/rte_ipsec_version.map
+++ b/lib/librte_ipsec/rte_ipsec_version.map
@@ -1,6 +1,9 @@ 
 EXPERIMENTAL {
 	global:
 
+	rte_ipsec_pkt_crypto_prepare;
+	rte_ipsec_session_prepare;
+	rte_ipsec_pkt_process;
 	rte_ipsec_sa_fini;
 	rte_ipsec_sa_init;
 	rte_ipsec_sa_size;
diff --git a/lib/librte_ipsec/sa.c b/lib/librte_ipsec/sa.c
index f927a82bf..e4c5361e7 100644
--- a/lib/librte_ipsec/sa.c
+++ b/lib/librte_ipsec/sa.c
@@ -2,7 +2,7 @@ 
  * Copyright(c) 2018 Intel Corporation
  */
 
-#include <rte_ipsec_sa.h>
+#include <rte_ipsec.h>
 #include <rte_esp.h>
 #include <rte_ip.h>
 #include <rte_errno.h>
@@ -325,3 +325,22 @@  rte_ipsec_sa_init(struct rte_ipsec_sa *sa, const struct rte_ipsec_sa_prm *prm,
 
 	return sz;
 }
+
+int
+ipsec_sa_pkt_func_select(const struct rte_ipsec_session *ss,
+	const struct rte_ipsec_sa *sa, struct rte_ipsec_sa_pkt_func *pf)
+{
+	int32_t rc;
+
+	RTE_SET_USED(sa);
+
+	rc = 0;
+	pf[0] = (struct rte_ipsec_sa_pkt_func) { 0 };
+
+	switch (ss->type) {
+	default:
+		rc = -ENOTSUP;
+	}
+
+	return rc;
+}
diff --git a/lib/librte_ipsec/sa.h b/lib/librte_ipsec/sa.h
index 5d113891a..050a6d7ae 100644
--- a/lib/librte_ipsec/sa.h
+++ b/lib/librte_ipsec/sa.h
@@ -74,4 +74,8 @@  struct rte_ipsec_sa {
 
 } __rte_cache_aligned;
 
+int
+ipsec_sa_pkt_func_select(const struct rte_ipsec_session *ss,
+	const struct rte_ipsec_sa *sa, struct rte_ipsec_sa_pkt_func *pf);
+
 #endif /* _SA_H_ */
diff --git a/lib/librte_ipsec/ses.c b/lib/librte_ipsec/ses.c
new file mode 100644
index 000000000..562c1423e
--- /dev/null
+++ b/lib/librte_ipsec/ses.c
@@ -0,0 +1,45 @@ 
+/* SPDX-License-Identifier: BSD-3-Clause
+ * Copyright(c) 2018 Intel Corporation
+ */
+
+#include <rte_ipsec.h>
+#include "sa.h"
+
+static int
+session_check(struct rte_ipsec_session *ss)
+{
+	if (ss == NULL || ss->sa == NULL)
+		return -EINVAL;
+
+	if (ss->type == RTE_SECURITY_ACTION_TYPE_NONE) {
+		if (ss->crypto.ses == NULL)
+			return -EINVAL;
+	} else if (ss->security.ses == NULL || ss->security.ctx == NULL)
+		return -EINVAL;
+
+	return 0;
+}
+
+int __rte_experimental
+rte_ipsec_session_prepare(struct rte_ipsec_session *ss)
+{
+	int32_t rc;
+	struct rte_ipsec_sa_pkt_func fp;
+
+	rc = session_check(ss);
+	if (rc != 0)
+		return rc;
+
+	rc = ipsec_sa_pkt_func_select(ss, ss->sa, &fp);
+	if (rc != 0)
+		return rc;
+
+	ss->pkt_func = fp;
+
+	if (ss->type == RTE_SECURITY_ACTION_TYPE_NONE)
+		ss->crypto.ses->opaque_data = (uintptr_t)ss;
+	else
+		ss->security.ses->opaque_data = (uintptr_t)ss;
+
+	return 0;
+}