[SCSI] scsi_transport_iscsi: Add support to set CHAP entries

For offload iSCSI like qla4xxx, CHAP entries are stored in adapter's
flash.
This patch adds support to add/update CHAP entries in adapter's flash
using iscsi tools, like Open-iSCSI.

Signed-off-by: Adheer Chandravanshi <adheer.chandravanshi@qlogic.com>
Signed-off-by: Vikas Chaudhary <vikas.chaudhary@qlogic.com>
Signed-off-by: James Bottomley <JBottomley@Parallels.com>
diff --git a/include/scsi/iscsi_if.h b/include/scsi/iscsi_if.h
index 13d81c5..5d6ed6c 100644
--- a/include/scsi/iscsi_if.h
+++ b/include/scsi/iscsi_if.h
@@ -69,6 +69,7 @@
 	ISCSI_UEVENT_LOGIN_FLASHNODE	= UEVENT_BASE + 28,
 	ISCSI_UEVENT_LOGOUT_FLASHNODE	= UEVENT_BASE + 29,
 	ISCSI_UEVENT_LOGOUT_FLASHNODE_SID	= UEVENT_BASE + 30,
+	ISCSI_UEVENT_SET_CHAP		= UEVENT_BASE + 31,
 
 	/* up events */
 	ISCSI_KEVENT_RECV_PDU		= KEVENT_BASE + 1,
@@ -309,8 +310,16 @@
 	ISCSI_HOST_PARAM,	/* iscsi_host_param */
 	ISCSI_NET_PARAM,	/* iscsi_net_param */
 	ISCSI_FLASHNODE_PARAM,	/* iscsi_flashnode_param */
+	ISCSI_CHAP_PARAM,	/* iscsi_chap_param */
 };
 
+/* structure for minimalist usecase */
+struct iscsi_param_info {
+	uint32_t len;		/* Actual length of the param value */
+	uint16_t param;		/* iscsi param */
+	uint8_t value[0];	/* length sized value follows */
+} __packed;
+
 struct iscsi_iface_param_info {
 	uint32_t iface_num;	/* iface number, 0 - n */
 	uint32_t len;		/* Actual length of the param */
@@ -739,6 +748,14 @@
 	CHAP_TYPE_IN,
 };
 
+enum iscsi_chap_param {
+	ISCSI_CHAP_PARAM_INDEX,
+	ISCSI_CHAP_PARAM_CHAP_TYPE,
+	ISCSI_CHAP_PARAM_USERNAME,
+	ISCSI_CHAP_PARAM_PASSWORD,
+	ISCSI_CHAP_PARAM_PASSWORD_LEN
+};
+
 #define ISCSI_CHAP_AUTH_NAME_MAX_LEN	256
 #define ISCSI_CHAP_AUTH_SECRET_MAX_LEN	256
 struct iscsi_chap_rec {