[PATCH 7/10][RFC] linux-iscsi driver

[PATCH 7/10][RFC] linux-iscsi driver

[Mike Christie]

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Handles iscsi logins.

[-- Attachment #2: 07-iscsi-login.patch --]
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diff -Naurp scsi-misc-2.6.orig/drivers/scsi/iscsi-sfnet/iscsi-login.c scsi-misc-2.6.patch/drivers/scsi/iscsi-sfnet/iscsi-login.c
--- scsi-misc-2.6.orig/drivers/scsi/iscsi-sfnet/iscsi-login.c	1969-12-31 16:00:00.000000000 -0800
+++ scsi-misc-2.6.patch/drivers/scsi/iscsi-sfnet/iscsi-login.c	2005-01-10 12:30:41.545574722 -0800
@@ -0,0 +1,1374 @@
+/*
+ * iSCSI login library
+ * Copyright (C) 2001 Cisco Systems, Inc.
+ * maintained by linux-iscsi-devel@lists.sourceforge.net
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * See the file COPYING included with this distribution for more details.
+ *
+ * Formation of iSCSI login pdu, processing the login response and other
+ * functions are defined here
+ */
+#include "iscsi-session.h"
+#include "iscsi-login.h"
+#include "iscsi-protocol.h"
+#include "iscsi-sfnet.h"
+
+/* caller is assumed to be well-behaved and passing NUL terminated strings */
+int
+iscsi_add_text(struct iscsi_session *session, struct iscsi_hdr *pdu, char *data,
+	       int max_data_length, char *param, char *value)
+{
+	int param_len = strlen(param);
+	int value_len = strlen(value);
+	int length = param_len + 1 + value_len + 1;	/* param, separator,
+							 * value, and trailing
+							 * NULL
+							 */
+	int pdu_length = ntoh24(pdu->dlength);
+	char *text = data;
+	char *end = data + max_data_length;
+	char *pdu_text;
+
+	/* find the end of the current text */
+	text += pdu_length;
+	pdu_text = text;
+	pdu_length += length;
+
+	if (text + length >= end) {
+		iscsi_host_notice(session, "Failed to add login text "
+				  "'%s=%s'\n", param, value);
+		return 0;
+	}
+
+	/* param */
+	strncpy(text, param, param_len);
+	text += param_len;
+
+	/* separator */
+	*text++ = ISCSI_TEXT_SEPARATOR;
+
+	/* value */
+	strncpy(text, value, value_len);
+	text += value_len;
+
+	/* NUL */
+	*text++ = '\0';
+
+	/* update the length in the PDU header */
+	hton24(pdu->dlength, pdu_length);
+
+	return 1;
+}
+
+static int
+iscsi_find_key_value(char *param, char *pdu, char *pdu_end, char **value_start,
+		     char **value_end)
+{
+	char *str = param;
+	char *text = pdu;
+	char *value;
+
+	if (value_start)
+		*value_start = NULL;
+	if (value_end)
+		*value_end = NULL;
+
+	/* make sure they contain the same bytes */
+	while (*str) {
+		if (text >= pdu_end)
+			return 0;
+		if (*text == '\0')
+			return 0;
+		if (*str != *text)
+			return 0;
+		str++;
+		text++;
+	}
+
+	if ((text >= pdu_end) || (*text == '\0')
+	    || (*text != ISCSI_TEXT_SEPARATOR)) {
+		return 0;
+	}
+
+	/* find the value */
+	value = text + 1;
+
+	/* find the end of the value */
+	while ((text < pdu_end) && (*text))
+		text++;
+
+	if (value_start)
+		*value_start = value;
+	if (value_end)
+		*value_end = text;
+
+	return 1;
+}
+
+static enum iscsi_login_status
+get_auth_key_type(struct iscsi_acl *auth_client, char **data, char *end)
+{
+	char *key;
+	char *value = NULL;
+        char *value_end = NULL;
+	char *text = *data;
+
+	int keytype = AUTH_KEY_TYPE_NONE;
+
+	while (acl_get_next_key_type(&keytype) == AUTH_STATUS_NO_ERROR) {
+		key = (char *)acl_get_key_name(keytype);
+
+		if (key && iscsi_find_key_value(key, text, end, &value,
+						&value_end)) {
+			if (acl_recv_key_value(auth_client, keytype, value) !=
+					       AUTH_STATUS_NO_ERROR) {
+				iscsi_err("login negotiation failed, can't "
+					  "accept %s in security stage\n",
+					  text);
+				return LOGIN_NEGOTIATION_FAILED;
+			}
+			text = value_end;
+			*data = text;
+			return LOGIN_OK;
+		}
+	}
+	iscsi_err("Login negotiation failed, can't accept %s in security "
+		  "stage\n", text);
+	return LOGIN_NEGOTIATION_FAILED;
+}
+
+static enum iscsi_login_status
+get_security_text_keys(struct iscsi_session *session, char **data,
+		       struct iscsi_acl *auth_client, char *end)
+{
+	char *text = *data;
+	char *value = NULL;
+	char *value_end = NULL;
+	size_t size;
+	int tag;
+	enum iscsi_login_status ret;
+
+	/*
+	 * a few keys are possible in Security stage
+	 * which the auth code doesn't care about, but
+	 * which we might want to see, or at least not
+	 * choke on.
+	 */
+	if (iscsi_find_key_value("TargetAlias", text, end, &value,
+		&value_end)) {
+		size = value_end - value;
+		session->target_alias = kmalloc(size + 1, GFP_ATOMIC);
+		if (!session->target_alias) {
+			/* Alias not critical. So just print an error */
+			iscsi_host_err(session, "Login failed to allocate "
+				       "alias\n");
+			*data = value_end;
+			return LOGIN_OK;
+		}
+		memcpy(session->target_alias, value, size);
+		session->target_alias[size] = '\0';
+		text = value_end;
+	} else if (iscsi_find_key_value("TargetAddress", text, end, &value,
+					 &value_end)) {
+		/*
+		 * if possible, change the session's
+		 * ip_address and port to the new
+		 * TargetAddress
+		 */
+		if (iscsi_update_address(session, value)) {
+			text = value_end;
+		} else {
+			iscsi_host_err(session, "Login redirection failed, "
+				       "can't handle redirection to %s\n",
+				       value);
+			return LOGIN_REDIRECTION_FAILED;
+		}
+	} else if (iscsi_find_key_value("TargetPortalGroupTag", text, end,
+					 &value, &value_end)) {
+		/*
+		 * We should have already obtained this
+		 * via discovery.
+		 * We've already picked an isid, so the
+		 * most we can do is confirm we reached
+		 * the portal group we were expecting to
+		 */
+		tag = simple_strtoul(value, NULL, 0);
+		if (session->portal_group_tag >= 0) {
+			if (tag != session->portal_group_tag) {
+				iscsi_host_err(session, "Portal group tag "
+					       "mismatch, expected %u, "
+					       "received %u\n",
+					       session->portal_group_tag, tag);
+				return LOGIN_WRONG_PORTAL_GROUP;
+			}
+		} else
+			/* we now know the tag */
+			session->portal_group_tag = tag;
+
+		text = value_end;
+	} else {
+		/*
+		 * any key we don't recognize either
+		 * goes to the auth code, or we choke
+		 * on it
+		 */
+		ret = get_auth_key_type(auth_client, &text, end);
+		if (ret != LOGIN_OK)
+			return ret;
+	}
+	*data = text;
+	return LOGIN_OK;
+}
+
+static enum iscsi_login_status
+get_op_params_text_keys(struct iscsi_session *session, char **data, char *end)
+{
+	char *text = *data;
+	char *value = NULL;
+	char *value_end = NULL;
+	size_t size;
+
+	if (iscsi_find_key_value("TargetAlias", text, end, &value,
+				 &value_end)) {
+		size = value_end - value;
+		if (session->target_alias &&
+		    strlen(session->target_alias) == size &&
+		    memcmp(session->target_alias, value, size) == 0) {
+			*data = value_end;
+			return LOGIN_OK;
+		}
+		kfree(session->target_alias);
+		session->target_alias = kmalloc(size + 1, GFP_ATOMIC);
+		if (!session->target_alias) {
+			/* Alias not critical. So just print an error */
+			iscsi_host_err(session, "Login failed to allocate "
+				       "alias\n");
+			*data = value_end;
+			return LOGIN_OK;
+		}
+		memcpy(session->target_alias, value, size);
+		session->target_alias[size] = '\0';
+		text = value_end;
+	} else if (iscsi_find_key_value("TargetAddress", text, end, &value,
+					 &value_end)) {
+		if (iscsi_update_address(session, value))
+			text = value_end;
+		else {
+			iscsi_host_err(session, "Login redirection failed, "
+				       "can't handle redirection to %s\n",
+				       value);
+			return LOGIN_REDIRECTION_FAILED;
+		}
+	} else if (iscsi_find_key_value("TargetPortalGroupTag", text, end,
+					 &value, &value_end)) {
+		/*
+		 * confirm we reached the portal group we were expecting to
+		 */
+		int tag = simple_strtoul(value, NULL, 0);
+		if (session->portal_group_tag >= 0) {
+			if (tag != session->portal_group_tag) {
+				iscsi_host_err(session, "Portal group tag "
+					       "mismatch, expected %u, "
+					       "received %u\n",
+					       session->portal_group_tag, tag);
+				return LOGIN_WRONG_PORTAL_GROUP;
+			}
+		} else
+			/* we now know the tag */
+			session->portal_group_tag = tag;
+
+		text = value_end;
+	} else if (iscsi_find_key_value("InitialR2T", text, end, &value,
+					 &value_end)) {
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL) {
+			if (value && (strcmp(value, "Yes") == 0))
+				session->initial_r2t = 1;
+			else
+				session->initial_r2t = 0;
+		} else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_INITIALR2T;
+		text = value_end;
+	} else if (iscsi_find_key_value("ImmediateData", text, end, &value,
+					 &value_end)) {
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL) {
+			if (value && (strcmp(value, "Yes") == 0))
+				session->immediate_data = 1;
+			else
+				session->immediate_data = 0;
+		} else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_IMMEDIATEDATA;
+		text = value_end;
+	} else if (iscsi_find_key_value("MaxRecvDataSegmentLength", text, end,
+				     &value, &value_end)) {
+		session->max_xmit_data_segment_len =
+					    simple_strtoul(value, NULL, 0);
+		text = value_end;
+	} else if (iscsi_find_key_value("FirstBurstLength", text, end, &value,
+					 &value_end)) {
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL)
+			session->first_burst_len =
+					    	simple_strtoul(value, NULL, 0);
+		else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_FIRSTBURSTLENGTH;
+		text = value_end;
+	} else if (iscsi_find_key_value("MaxBurstLength", text, end, &value,
+					 &value_end)) {
+		/*
+		 * we don't really care, since it's a  limit on the target's
+		 * R2Ts, but record it anwyay
+		 */
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL)
+			session->max_burst_len = simple_strtoul(value, NULL, 0);
+		else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_MAXBURSTLENGTH;
+		text = value_end;
+	} else if (iscsi_find_key_value("HeaderDigest", text, end, &value,
+					 &value_end)) {
+		if (strcmp(value, "None") == 0) {
+			if (session->header_digest != ISCSI_DIGEST_CRC32C)
+				session->header_digest = ISCSI_DIGEST_NONE;
+			else {
+				iscsi_host_err(session, "Login negotiation "
+					       "failed, HeaderDigest=CRC32C "
+					       "is required, can't accept "
+					       "%s\n", text);
+				return LOGIN_NEGOTIATION_FAILED;
+			}
+		} else if (strcmp(value, "CRC32C") == 0) {
+			if (session->header_digest != ISCSI_DIGEST_NONE)
+				session->header_digest = ISCSI_DIGEST_CRC32C;
+			else {
+				iscsi_host_err(session, "Login negotiation "
+					       "failed, HeaderDigest=None is "
+					       "required, can't accept %s\n",
+					       text);
+				return LOGIN_NEGOTIATION_FAILED;
+			}
+		} else {
+			iscsi_host_err(session, "Login negotiation failed, "
+				       "can't accept %s\n", text);
+			return LOGIN_NEGOTIATION_FAILED;
+		}
+		text = value_end;
+	} else if (iscsi_find_key_value("DataDigest", text, end, &value,
+					 &value_end)) {
+		if (strcmp(value, "None") == 0) {
+			if (session->data_digest != ISCSI_DIGEST_CRC32C)
+				session->data_digest = ISCSI_DIGEST_NONE;
+			else {
+				iscsi_host_err(session, "Login negotiation "
+					       "failed, DataDigest=CRC32C "
+					       "is required, can't accept "
+					       "%s\n", text);
+				return LOGIN_NEGOTIATION_FAILED;
+			}
+		} else if (strcmp(value, "CRC32C") == 0) {
+			if (session->data_digest != ISCSI_DIGEST_NONE)
+				session->data_digest = ISCSI_DIGEST_CRC32C;
+			else {
+				iscsi_host_err(session, "Login negotiation "
+					       "failed, DataDigest=None is "
+					       "required, can't accept %s\n",
+					       text);
+				return LOGIN_NEGOTIATION_FAILED;
+			}
+		} else {
+			iscsi_host_err(session, "Login negotiation failed, "
+				       "can't accept %s\n", text);
+			return LOGIN_NEGOTIATION_FAILED;
+		}
+		text = value_end;
+	} else if (iscsi_find_key_value("DefaultTime2Wait", text, end, &value,
+					 &value_end)) {
+		session->def_time2wait = simple_strtoul(value, NULL, 0);
+		text = value_end;
+	} else if (iscsi_find_key_value("DefaultTime2Retain", text, end,
+					 &value, &value_end)) {
+		session->def_time2retain = simple_strtoul(value, NULL, 0);
+		text = value_end;
+	} else if (iscsi_find_key_value("OFMarker", text, end, &value,
+					 &value_end))
+		/* result function is AND, target must honor our No */
+		text = value_end;
+	else if (iscsi_find_key_value("OFMarkInt", text, end, &value,
+					 &value_end))
+		/* we don't do markers, so we don't care */
+		text = value_end;
+	else if (iscsi_find_key_value("IFMarker", text, end, &value,
+					 &value_end))
+		/* result function is AND, target must honor our No */
+		text = value_end;
+	else if (iscsi_find_key_value("IFMarkInt", text, end, &value,
+					 &value_end))
+		/* we don't do markers, so we don't care */
+		text = value_end;
+	else if (iscsi_find_key_value("DataPDUInOrder", text, end, &value,
+					 &value_end)) {
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL) {
+			if (value && strcmp(value, "Yes") == 0)
+				session->data_pdu_in_order = 1;
+			else
+				session->data_pdu_in_order = 0;
+		} else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_DATAPDUINORDER;
+		text = value_end;
+	} else if (iscsi_find_key_value ("DataSequenceInOrder", text, end,
+					 &value, &value_end)) {
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL)
+			if (value && strcmp(value, "Yes") == 0)
+				session->data_seq_in_order = 1;
+			else
+				session->data_seq_in_order = 0;
+		else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_DATASEQUENCEINORDER;
+		text = value_end;
+	} else if (iscsi_find_key_value("MaxOutstandingR2T", text, end, &value,
+					 &value_end)) {
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL) {
+			if (strcmp(value, "1")) {
+				iscsi_host_err(session, "Login negotiation "
+					       "failed, can't accept Max"
+					       "OutstandingR2T %s\n", value);
+				return LOGIN_NEGOTIATION_FAILED;
+			}
+		} else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_MAXOUTSTANDINGR2T;
+		text = value_end;
+	} else if (iscsi_find_key_value("MaxConnections", text, end, &value,
+					 &value_end)) {
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL) {
+			if (strcmp(value, "1")) {
+				iscsi_host_err(session, "Login negotiation "
+					       "failed, can't accept Max"
+					       "Connections %s\n", value);
+				return LOGIN_NEGOTIATION_FAILED;
+			}
+		} else
+			session->irrelevant_keys_bitmap |=
+						IRRELEVANT_MAXCONNECTIONS;
+		text = value_end;
+	} else if (iscsi_find_key_value("ErrorRecoveryLevel", text, end,
+					 &value, &value_end)) {
+		if (strcmp(value, "0")) {
+			iscsi_host_err(session, "Login negotiation failed, "
+				       "can't accept ErrorRecovery %s\n",
+				       value);
+			return LOGIN_NEGOTIATION_FAILED;
+		}
+		text = value_end;
+	} else if (iscsi_find_key_value ("X-com.cisco.protocol", text, end,
+					 &value, &value_end)) {
+		if (strcmp(value, "NotUnderstood") &&
+		    strcmp(value, "Reject") &&
+		    strcmp(value, "Irrelevant") &&
+		    strcmp(value, "draft20")) {
+			/* if we didn't get a compatible protocol, fail */
+			iscsi_host_err(session, "Login version mismatch, "
+				       "can't accept protocol %s\n", value);
+			return LOGIN_VERSION_MISMATCH;
+		}
+		text = value_end;
+	} else if (iscsi_find_key_value("X-com.cisco.PingTimeout", text, end,
+					 &value, &value_end))
+		/* we don't really care what the target ends up using */
+		text = value_end;
+	else if (iscsi_find_key_value("X-com.cisco.sendAsyncText", text, end,
+					 &value, &value_end))
+		/* we don't bother for the target response */
+		text = value_end;
+	else {
+		iscsi_host_err(session, "Login negotiation failed, couldn't "
+			       "recognize text %s\n", text);
+		return LOGIN_NEGOTIATION_FAILED;
+	}
+	*data = text;
+	return LOGIN_OK;
+}
+
+static enum iscsi_login_status
+check_security_stage_status(struct iscsi_session *session,
+			    struct iscsi_acl *auth_client)
+{
+	int debug_status = 0;
+
+	switch (acl_recv_end(auth_client)) {
+	case AUTH_STATUS_CONTINUE:
+		/* continue sending PDUs */
+		break;
+
+	case AUTH_STATUS_PASS:
+		break;
+
+	case AUTH_STATUS_NO_ERROR:	/* treat this as an error,
+					 * since we should get a
+					 * different code
+					 */
+	case AUTH_STATUS_ERROR:
+	case AUTH_STATUS_FAIL:
+	default:
+		if (acl_get_dbg_status(auth_client, &debug_status) !=
+		    AUTH_STATUS_NO_ERROR)
+			iscsi_host_err(session, "Login authentication failed "
+				       "with target %s, %s\n",
+				       session->target_name,
+				       acl_dbg_status_to_text(debug_status));
+		else
+			iscsi_host_err(session, "Login authentication failed "
+				       "with target %s\n",
+				       session->target_name);
+		return LOGIN_AUTHENTICATION_FAILED;
+	}
+	return LOGIN_OK;
+}
+
+/*
+ * this assumes the text data is always NULL terminated.  The caller can
+ * always arrange for that by using a slightly larger buffer than the max PDU
+ * size, and then appending a NULL to the PDU.
+ */
+static enum iscsi_login_status
+iscsi_process_login_response(struct iscsi_session *session,
+			     struct iscsi_login_rsp_hdr *login_rsp_pdu,
+			     char *data, int max_data_length)
+{
+	int transit = login_rsp_pdu->flags & ISCSI_FLAG_LOGIN_TRANSIT;
+	char *text = data;
+	char *end;
+	int pdu_current_stage, pdu_next_stage;
+	enum iscsi_login_status ret;
+	struct iscsi_acl *auth_client = session->auth_client_block ?
+					session->auth_client_block : NULL;
+
+	end = text + ntoh24(login_rsp_pdu->dlength) + 1;
+	if (end >= (data + max_data_length)) {
+		iscsi_host_err(session, "Login failed, process_login_response "
+			       "buffer too small to guarantee NULL "
+			       "termination\n");
+		return LOGIN_FAILED;
+	}
+
+	/* guarantee a trailing NUL */
+	*end = '\0';
+
+	/* if the response status was success, sanity check the response */
+	if (login_rsp_pdu->status_class == ISCSI_STATUS_CLS_SUCCESS) {
+		/* check the active version */
+		if (login_rsp_pdu->active_version != ISCSI_DRAFT20_VERSION) {
+			iscsi_host_err(session, "Login version mismatch, "
+				       "received incompatible active iSCSI "
+				       "version 0x%02x, expected version "
+				       "0x%02x\n",
+				       login_rsp_pdu->active_version,
+				       ISCSI_DRAFT20_VERSION);
+			return LOGIN_VERSION_MISMATCH;
+		}
+
+		/* make sure the current stage matches */
+		pdu_current_stage = (login_rsp_pdu->flags &
+				    ISCSI_FLAG_LOGIN_CURRENT_STAGE_MASK) >> 2;
+		if (pdu_current_stage != session->current_stage) {
+			iscsi_host_err(session, "Received invalid login PDU, "
+				       "current stage mismatch, session %d, "
+				       "response %d\n", session->current_stage,
+				       pdu_current_stage);
+			return LOGIN_INVALID_PDU;
+		}
+
+		/*
+		 * make sure that we're actually advancing if the T-bit is set
+		 */
+		pdu_next_stage = login_rsp_pdu->flags &
+				 ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK;
+		if (transit && (pdu_next_stage <= session->current_stage))
+			return LOGIN_INVALID_PDU;
+	}
+
+	if (session->current_stage == ISCSI_SECURITY_NEGOTIATION_STAGE) {
+		if (acl_recv_begin(auth_client) != AUTH_STATUS_NO_ERROR) {
+			iscsi_host_err(session, "Login failed because "
+				       "acl_recv_begin failed\n");
+			return LOGIN_FAILED;
+		}
+
+		if (acl_recv_transit_bit(auth_client, transit) !=
+		    AUTH_STATUS_NO_ERROR) {
+			iscsi_host_err(session, "Login failed because "
+				  "acl_recv_transit_bit failed\n");
+			return LOGIN_FAILED;
+		}
+	}
+
+	/* scan the text data */
+	while (text && (text < end)) {
+		/* skip any NULs separating each text key=value pair */
+		while ((text < end) && (*text == '\0'))
+			text++;
+		if (text >= end)
+			break;
+
+		/* handle keys appropriate for each stage */
+		switch (session->current_stage) {
+		case ISCSI_SECURITY_NEGOTIATION_STAGE:{
+				ret = get_security_text_keys(session, &text,
+							     auth_client, end);
+				if (ret != LOGIN_OK)
+					return ret;
+				break;
+			}
+		case ISCSI_OP_PARMS_NEGOTIATION_STAGE:{
+				ret = get_op_params_text_keys(session, &text,
+							      end);
+				if (ret != LOGIN_OK)
+					return ret;
+				break;
+			}
+		default:
+			return LOGIN_FAILED;
+		}
+	}
+
+	if (session->current_stage == ISCSI_SECURITY_NEGOTIATION_STAGE) {
+		ret = check_security_stage_status(session, auth_client);
+		if (ret != LOGIN_OK)
+			return ret;
+	}
+	/* record some of the PDU fields for later use */
+	session->tsih = ntohs(login_rsp_pdu->tsih);
+	session->exp_cmd_sn = ntohl(login_rsp_pdu->expcmdsn);
+	session->max_cmd_sn = ntohl(login_rsp_pdu->maxcmdsn);
+	if (login_rsp_pdu->status_class == ISCSI_STATUS_CLS_SUCCESS)
+		session->exp_stat_sn = ntohl(login_rsp_pdu->statsn) + 1;
+
+	if (transit) {
+		/* advance to the next stage */
+		session->partial_response = 0;
+		session->current_stage = login_rsp_pdu->flags &
+					 ISCSI_FLAG_LOGIN_NEXT_STAGE_MASK;
+		session->irrelevant_keys_bitmap = 0;
+	} else
+		/*
+		 * we got a partial response, don't advance,
+		 * more negotiation to do
+		 */
+		session->partial_response = 1;
+
+	return LOGIN_OK;	/* this PDU is ok, though the login process
+				 * may not be done yet
+				 */
+}
+
+static int
+add_params_normal_session(struct iscsi_session *session, struct iscsi_hdr *pdu,
+                    char *data, int max_data_length)
+{
+	char value[AUTH_STR_MAX_LEN];
+
+	/* these are only relevant for normal sessions */
+	if (!iscsi_add_text(session, pdu, data, max_data_length, "InitialR2T",
+			    session->initial_r2t ? "Yes" : "No"))
+		return 0;
+
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "ImmediateData",
+			    session->immediate_data ? "Yes" : "No"))
+		return 0;
+
+	sprintf(value, "%d", session->max_burst_len);
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "MaxBurstLength", value))
+		return 0;
+
+	sprintf(value, "%d",session->first_burst_len);
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "FirstBurstLength", value))
+		return 0;
+
+	/* these we must have */
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "MaxOutstandingR2T", "1"))
+		return 0;
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "MaxConnections", "1"))
+		return 0;
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "DataPDUInOrder", "Yes"))
+		return 0;
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "DataSequenceInOrder", "Yes"))
+		return 0;
+
+	return 1;
+}
+
+static int
+add_vendor_specific_text(struct iscsi_session *session, struct iscsi_hdr *pdu,
+                    char *data, int max_data_length)
+{
+	char value[AUTH_STR_MAX_LEN];
+
+	/*
+	 * adjust the target's PingTimeout for normal sessions,
+	 * so that it matches the driver's ping timeout.  The
+	 * network probably has the same latency in both
+	 * directions, so the values ought to match.
+	 */
+	if (session->ping_timeout >= 0) {
+		sprintf(value, "%d", session->ping_timeout);
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "X-com.cisco.PingTimeout", value))
+			return 0;
+	}
+
+	if (session->send_async_text >= 0)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "X-com.cisco.sendAsyncText",
+				    session->send_async_text ? "Yes" : "No"))
+			return 0;
+
+	/*
+	 * vendor-specific protocol specification. list of protocol level
+	 * strings in order of preference allowable values are: draft<n>
+	 * (e.g. draft8), rfc<n> (e.g. rfc666).
+	 * For example: "X-com.cisco.protocol=draft20,draft8" requests draft 20,
+	 * or 8 if 20 isn't supported. "X-com.cisco.protocol=draft8,draft20"
+	 * requests draft 8, or 20 if 8 isn't supported. Targets that
+	 * understand this key SHOULD return the protocol level they selected
+	 * as a response to this key, though the active_version may be
+	 * sufficient to distinguish which protocol was chosen.
+	 * Note: This probably won't work unless we start in op param stage,
+	 * since the security stage limits what keys we can send, and we'd need
+	 * to have sent this on the first PDU of the login.  Keep sending it for
+	 * informational use, and so that we can sanity check things later if
+	 * the RFC and draft20 are using the same active version number,
+	 * but have non-trivial differences.
+	 */
+	if (!iscsi_add_text(session, pdu, data, max_data_length,
+			     "X-com.cisco.protocol", "draft20"))
+		return 0;
+
+	return 1;
+}
+
+static int
+check_irrelevant_keys(struct iscsi_session *session, struct iscsi_hdr *pdu,
+                    char *data, int max_data_length)
+{
+	/* If you receive irrelevant keys, just check them from the irrelevant
+	 * keys bitmap and respond with the key=Irrelevant text
+	 */
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_MAXCONNECTIONS)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "MaxConnections", "Irrelevant"))
+			return 0;
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_INITIALR2T)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "InitialR2T", "Irrelevant"))
+			return 0;
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_IMMEDIATEDATA)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "ImmediateData", "Irrelevant"))
+			return 0;
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_MAXBURSTLENGTH)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "MaxBurstLength", "Irrelevant"))
+			return 0;
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_FIRSTBURSTLENGTH)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "FirstBurstLength", "Irrelevant"))
+			return 0;
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_MAXOUTSTANDINGR2T)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "MaxOutstandingR2T", "Irrelevant"))
+			return 0;
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_DATAPDUINORDER)
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "DataPDUInOrder", "Irrelevant"))
+			return 0;
+
+	if (session->irrelevant_keys_bitmap & IRRELEVANT_DATASEQUENCEINORDER )
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "DataSequenceInOrder", "Irrelevant"))
+			return 0;
+
+	return 1;
+}
+
+static int
+fill_crc_digest_text(struct iscsi_session *session, struct iscsi_hdr *pdu,
+		     char *data, int max_data_length)
+{
+	switch (session->header_digest) {
+	case ISCSI_DIGEST_NONE:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "HeaderDigest", "None"))
+			return 0;
+		break;
+	case ISCSI_DIGEST_CRC32C:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "HeaderDigest", "CRC32C"))
+			return 0;
+		break;
+	case ISCSI_DIGEST_CRC32C_NONE:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "HeaderDigest", "CRC32C,None"))
+			return 0;
+		break;
+	default:
+	case ISCSI_DIGEST_NONE_CRC32C:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "HeaderDigest", "None,CRC32C"))
+			return 0;
+		break;
+	}
+
+	switch (session->data_digest) {
+	case ISCSI_DIGEST_NONE:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "DataDigest", "None"))
+			return 0;
+		break;
+	case ISCSI_DIGEST_CRC32C:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "DataDigest", "CRC32C"))
+			return 0;
+		break;
+	case ISCSI_DIGEST_CRC32C_NONE:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "DataDigest", "CRC32C,None"))
+			return 0;
+		break;
+	default:
+	case ISCSI_DIGEST_NONE_CRC32C:
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "DataDigest", "None,CRC32C"))
+			return 0;
+		break;
+	}
+	return 1;
+}
+
+static int
+fill_op_params_text(struct iscsi_session *session, struct iscsi_hdr *pdu,
+		    char *data, int max_data_length, int *transit)
+{
+	char value[AUTH_STR_MAX_LEN];
+
+	/* we always try to go from op params to full feature stage */
+	session->current_stage = ISCSI_OP_PARMS_NEGOTIATION_STAGE;
+	session->next_stage = ISCSI_FULL_FEATURE_PHASE;
+	*transit = 1;
+
+	/*
+	 * If we haven't gotten a partial response, then either we shouldn't be
+	 * here, or we just switched to this stage, and need to start offering
+	 * keys.
+	 */
+	if (!session->partial_response) {
+		/*
+		 * request the desired settings the first time
+		 * we are in this stage
+		 */
+		if (!fill_crc_digest_text(session, pdu, data, max_data_length))
+			return 0;
+
+		sprintf(value, "%d", session->max_recv_data_segment_len);
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "MaxRecvDataSegmentLength", value))
+			return 0;
+
+		sprintf(value, "%d", session->def_time2wait);
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "DefaultTime2Wait", value))
+			return 0;
+
+		sprintf(value, "%d", session->def_time2retain);
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "DefaultTime2Retain", value))
+			return 0;
+
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "IFMarker", "No"))
+			return 0;
+
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "OFMarker", "No"))
+			return 0;
+
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+				    "ErrorRecoveryLevel", "0"))
+			return 0;
+
+		if (session->type == ISCSI_SESSION_TYPE_NORMAL)
+			if (!add_params_normal_session(session, pdu, data,
+						  max_data_length))
+				return 0;
+
+		/*
+		 * Note: 12.22 forbids vendor-specific keys on discovery
+		 * sessions, so the caller is violating the spec if it asks for
+		 * these on a discovery session.
+		 */
+		if (session->vendor_specific_keys)
+			if (!add_vendor_specific_text(session, pdu, data,
+						      max_data_length))
+				return 0;
+	} else if (!check_irrelevant_keys(session, pdu, data, max_data_length))
+		return 0;
+
+	return 1;
+}
+
+static void
+enum_auth_keys(struct iscsi_acl *auth_client, struct iscsi_hdr *pdu,
+	       char *data, int max_data_length, int keytype)
+{
+	int present = 0, rc;
+	char *key = (char *)acl_get_key_name(keytype);
+	int key_length = key ? strlen(key) : 0;
+	int pdu_length = ntoh24(pdu->dlength);
+	char *auth_value = data + pdu_length + key_length + 1;
+	unsigned int max_length = max_data_length - (pdu_length
+					  + key_length + 1);
+
+	/*
+	 * add the key/value pairs the auth code wants to send
+	 * directly to the PDU, since they could in theory be large.
+	 */
+	rc = acl_send_key_val(auth_client, keytype, &present, auth_value,
+			      max_length);
+	if ((rc == AUTH_STATUS_NO_ERROR) && present) {
+		/* actually fill in the key */
+		strncpy(&data[pdu_length], key, key_length);
+		pdu_length += key_length;
+		data[pdu_length] = '=';
+		pdu_length++;
+		/*
+		 * adjust the PDU's data segment length
+		 * to include the value and trailing NUL
+		 */
+		pdu_length += strlen(auth_value) + 1;
+		hton24(pdu->dlength, pdu_length);
+	}
+}
+
+static int
+fill_security_params_text(struct iscsi_session *session, struct iscsi_hdr *pdu,
+			  struct iscsi_acl *auth_client, char *data,
+			  int max_data_length, int *transit)
+{
+	int keytype = AUTH_KEY_TYPE_NONE;
+	int rc = acl_send_transit_bit(auth_client, transit);
+
+	/* see if we're ready for a stage change */
+	if (rc != AUTH_STATUS_NO_ERROR)
+		return 0;
+
+	if (*transit) {
+		/*
+		 * discovery sessions can go right to full-feature phase,
+		 * unless they want to non-standard values for the few relevant
+		 * keys, or want to offer vendor-specific keys
+		 */
+		if (session->type == ISCSI_SESSION_TYPE_DISCOVERY)
+			if ((session->header_digest != ISCSI_DIGEST_NONE) ||
+			    (session->data_digest != ISCSI_DIGEST_NONE) ||
+			    (session-> max_recv_data_segment_len !=
+			    DEFAULT_MAX_RECV_DATA_SEGMENT_LENGTH) ||
+			    session->vendor_specific_keys)
+				session->next_stage =
+					    ISCSI_OP_PARMS_NEGOTIATION_STAGE;
+			else
+				session->next_stage = ISCSI_FULL_FEATURE_PHASE;
+		else
+			session->next_stage = ISCSI_OP_PARMS_NEGOTIATION_STAGE;
+	} else
+		session->next_stage = ISCSI_SECURITY_NEGOTIATION_STAGE;
+
+	/* enumerate all the keys the auth code might want to send */
+	while (acl_get_next_key_type(&keytype) == AUTH_STATUS_NO_ERROR)
+		enum_auth_keys(auth_client, pdu, data, max_data_length,
+			       keytype);
+
+	return 1;
+}
+
+/**
+ * iscsi_make_login_pdu - Prepare the login pdu to be sent to iSCSI target.
+ * @session: session for which login is initiated.
+ * @pdu: login header
+ * @data: contains text keys to be negotiated during login
+ * @max_data_length: data size
+ *
+ * Description:
+ *     Based on whether authentication is enabled or not, corresponding text
+ *     keys are filled up in login pdu.
+ *
+ **/
+static int
+iscsi_make_login_pdu(struct iscsi_session *session, struct iscsi_hdr *pdu,
+		     char *data, int max_data_length)
+{
+	int transit = 0;
+	int ret;
+	struct iscsi_login_hdr *login_pdu = (struct iscsi_login_hdr *)pdu;
+	struct iscsi_acl *auth_client = session->auth_client_block ?
+					session->auth_client_block : NULL;
+
+	/* initialize the PDU header */
+	memset(login_pdu, 0, sizeof(*login_pdu));
+	login_pdu->opcode = ISCSI_OP_LOGIN_CMD | ISCSI_OP_IMMEDIATE;
+	login_pdu->cid = 0;
+	memcpy(login_pdu->isid, session->isid, sizeof(session->isid));
+	login_pdu->tsih = 0;
+	login_pdu->cmdsn = htonl(session->cmd_sn);	
+	/* don't increment on immediate */
+	login_pdu->min_version = ISCSI_DRAFT20_VERSION;
+	login_pdu->max_version = ISCSI_DRAFT20_VERSION;
+
+	/* we have to send 0 until full-feature stage */
+	login_pdu->expstatsn = htonl(session->exp_stat_sn);
+
+	/*
+	 * the very first Login PDU has some additional requirements,
+	 * and we need to decide what stage to start in.
+	 */
+	if (session->current_stage == ISCSI_INITIAL_LOGIN_STAGE) {
+		if (session->initiator_name && session->initiator_name[0]) {
+			if (!iscsi_add_text(session, pdu, data, max_data_length,
+			     "InitiatorName", session->initiator_name))
+				return 0;
+		} else {
+			iscsi_host_err(session, "InitiatorName is required "
+				       "on the first Login PDU\n");
+			return 0;
+		}
+		if (session->initiator_alias && session->initiator_alias[0]) {
+			if (!iscsi_add_text(session, pdu, data, max_data_length,
+			     "InitiatorAlias", session->initiator_alias))
+				return 0;
+		}
+
+		if ((session->target_name && session->target_name[0]) &&
+		    (session->type == ISCSI_SESSION_TYPE_NORMAL)) {
+			if (!iscsi_add_text(session, pdu, data, max_data_length,
+			    "TargetName", session->target_name))
+				return 0;
+		}
+
+		if (!iscsi_add_text(session, pdu, data, max_data_length,
+		    "SessionType", (session->type ==
+		      ISCSI_SESSION_TYPE_DISCOVERY) ? "Discovery" : "Normal"))
+			return 0;
+
+		if (auth_client)
+			/* we're prepared to do authentication */
+			session->current_stage = session->next_stage =
+			    ISCSI_SECURITY_NEGOTIATION_STAGE;
+		else
+			/* can't do any authentication, skip that stage */
+			session->current_stage = session->next_stage =
+			    ISCSI_OP_PARMS_NEGOTIATION_STAGE;
+	}
+
+	/* fill in text based on the stage */
+	switch (session->current_stage) {
+	case ISCSI_OP_PARMS_NEGOTIATION_STAGE:{
+			ret = fill_op_params_text(session, pdu, data,
+						  max_data_length, &transit);
+			if (!ret)
+				return ret;
+			break;
+		}
+	case ISCSI_SECURITY_NEGOTIATION_STAGE:{
+			ret = fill_security_params_text(session, pdu,
+							auth_client, data,
+							max_data_length,
+						  	&transit);
+			if (!ret)
+				return ret;
+			break;
+		}
+	case ISCSI_FULL_FEATURE_PHASE:
+		iscsi_host_err(session, "Can't send login PDUs in full "
+			       "feature phase\n");
+		return 0;
+	default:
+		iscsi_host_err(session, "Can't send login PDUs in unknown "
+			       "stage %d\n", session->current_stage);
+		return 0;
+	}
+
+	/* fill in the flags */
+	login_pdu->flags = 0;
+	login_pdu->flags |= session->current_stage << 2;
+	if (transit) {
+		/* transit to the next stage */
+		login_pdu->flags |= session->next_stage;
+		login_pdu->flags |= ISCSI_FLAG_LOGIN_TRANSIT;
+	} else
+		/* next == current */
+		login_pdu->flags |= session->current_stage;
+
+	return 1;
+}
+
+static enum iscsi_login_status
+check_for_authentication(struct iscsi_session *session,
+			 struct iscsi_acl **auth_client)
+{
+	/* prepare for authentication */
+	if (acl_init(TYPE_INITIATOR, session) != AUTH_STATUS_NO_ERROR) {
+		iscsi_host_err(session, "Couldn't initialize authentication\n");
+		return LOGIN_FAILED;
+	}
+
+	*auth_client = session->auth_client_block;
+
+	if (session->username && 
+	    (acl_set_user_name(*auth_client, session->username) !=
+	    AUTH_STATUS_NO_ERROR)) {
+		iscsi_host_err(session, "Couldn't set username\n");
+		goto end;
+	}
+
+	if (session->password && (acl_set_passwd(*auth_client,
+	    session->password, session->password_length) !=
+		 AUTH_STATUS_NO_ERROR)) {
+		iscsi_host_err(session, "Couldn't set password\n");
+		goto end;
+	}
+
+	if (acl_set_ip_sec(*auth_client, 1) != AUTH_STATUS_NO_ERROR) {
+		iscsi_host_err(session, "Couldn't set IPSec\n");
+		goto end;
+	}
+
+	if (acl_set_auth_rmt(*auth_client, session->bidirectional_auth) !=
+			     AUTH_STATUS_NO_ERROR) {
+		iscsi_host_err(session, "Couldn't set remote authentication\n");
+		goto end;
+	}
+	return LOGIN_OK;
+
+ end:
+	if (*auth_client && acl_finish(*auth_client) != AUTH_STATUS_NO_ERROR)
+		iscsi_host_err(session, "Login failed, error finishing "
+			       "auth_client\n");
+	*auth_client = NULL;
+	return LOGIN_FAILED;
+}
+
+static enum iscsi_login_status
+check_status_login_response(struct iscsi_session *session,
+			    struct iscsi_login_rsp_hdr *login_rsp_pdu,
+			    char *data, int max_data_length, int *final)
+{
+	enum iscsi_login_status ret;
+
+	switch (login_rsp_pdu->status_class) {
+	case ISCSI_STATUS_CLS_SUCCESS:
+		/* process this response and possibly continue sending PDUs */
+		ret = iscsi_process_login_response(session, login_rsp_pdu,
+						   data, max_data_length);
+		if (ret != LOGIN_OK)	/* pass back whatever
+					 * error we discovered
+					 */
+			*final = 1;
+		break;
+	case ISCSI_STATUS_CLS_REDIRECT:
+		/*
+		 * we need to process this response to get the
+		 * TargetAddress of the redirect, but we don't care
+		 * about the return code.
+		 */
+		iscsi_process_login_response(session, login_rsp_pdu,
+					     data, max_data_length);
+		ret = LOGIN_OK;
+		*final = 1;
+	case ISCSI_STATUS_CLS_INITIATOR_ERR:
+		if (login_rsp_pdu->status_detail ==
+		    ISCSI_LOGIN_STATUS_AUTH_FAILED) {
+			iscsi_host_err(session, "Login failed to authenticate "
+				       "with target %s\n",
+				       session->target_name);
+		}
+		ret = LOGIN_OK;
+		*final = 1;
+	default:
+		/*
+		 * some sort of error, login terminated unsuccessfully,
+		 * though this function did it's job.
+		 * the caller must check the status_class and
+		 * status_detail and decide what to do next.
+		 */
+		ret = LOGIN_OK;
+		*final = 1;
+	}
+	return ret;
+}
+
+/**
+ * iscsi_login - attempt to login to the target.
+ * @session: login is initiated over this session
+ * @buffer: holds login pdu
+ * @bufsize: size of login pdu
+ * @status_class: holds either success or failure as status of login
+ * @status_detail: contains details based on the login status
+ *
+ * Description:
+ *     The caller must check the status class to determine if the login
+ *     succeeded. A return of 1 does not mean the login succeeded, it just
+ *     means this function worked, and the status class is valid info.
+ *     This allows the caller to decide whether or not to retry logins, so
+ *     that we don't have any policy logic here.
+ **/
+enum iscsi_login_status
+iscsi_login(struct iscsi_session *session, char *buffer, size_t bufsize,
+	    u8 *status_class, u8 *status_detail)
+{
+	struct iscsi_acl *auth_client = NULL;
+	struct iscsi_hdr pdu;
+	struct iscsi_login_rsp_hdr *login_rsp_pdu;
+	char *data;
+	int received_pdu = 0;
+	int max_data_length;
+	int final = 0;
+	enum iscsi_login_status ret = LOGIN_FAILED;
+
+	/* prepare the session */
+	session->cmd_sn = 1;
+	session->exp_cmd_sn = 1;
+	session->max_cmd_sn = 1;
+	session->exp_stat_sn = 0;
+
+	session->current_stage = ISCSI_INITIAL_LOGIN_STAGE;
+	session->partial_response = 0;
+
+	if (session->auth_client_block) {
+		ret = check_for_authentication(session, &auth_client);
+		if (ret != LOGIN_OK)
+			return ret;
+	}
+
+	/*
+	 * exchange PDUs until the login stage is complete, or an error occurs
+	 */
+	do {
+		final = 0;
+		login_rsp_pdu = (struct iscsi_login_rsp_hdr *)&pdu;
+		ret = LOGIN_FAILED;
+
+		memset(buffer, 0, bufsize);
+		data = buffer;
+		max_data_length = bufsize;
+
+		/*
+		 * fill in the PDU header and text data based on the login
+		 * stage that we're in
+		 */
+		if (!iscsi_make_login_pdu(session, &pdu, data,
+					  max_data_length)) {
+			iscsi_host_err(session, "login failed, couldn't make "
+				       "a login PDU\n");
+			ret = LOGIN_FAILED;
+			goto done;
+		}
+
+		/* send a PDU to the target */
+		if (!iscsi_send_pdu(session, &pdu, ISCSI_DIGEST_NONE,
+				    data, ISCSI_DIGEST_NONE)) {
+			/*
+			 * FIXME: caller might want us to distinguish I/O
+			 * error and timeout. Might want to switch portals on
+			 * timeouts, but
+			 * not I/O errors.
+			 */
+			iscsi_host_err(session, "Login I/O error, failed to "
+				       "send a PDU\n");
+			ret = LOGIN_IO_ERROR;
+			goto done;
+		}
+
+		/* read the target's response into the same buffer */
+		if (!iscsi_recv_pdu(session, &pdu, ISCSI_DIGEST_NONE, data,
+				    max_data_length, ISCSI_DIGEST_NONE)) {
+			/*
+			 * FIXME: caller might want us to distinguish I/O
+			 * error and timeout. Might want to switch portals on
+			 * timeouts, but not I/O errors.
+			 */
+			iscsi_host_err(session, "Login I/O error, failed to "
+				       "receive a PDU\n");
+			ret = LOGIN_IO_ERROR;
+			goto done;
+		}
+
+		received_pdu = 1;
+
+		/* check the PDU response type */
+		if (pdu.opcode == (ISCSI_OP_LOGIN_RSP | 0xC0)) {
+			/*
+			 * it's probably a draft 8 login response,
+			 * which we can't deal with
+			 */
+			iscsi_host_err(session, "Received iSCSI draft 8 login "
+				       "response opcode 0x%x, expected draft "
+				       "20 login response 0x%2x\n",
+				       pdu.opcode, ISCSI_OP_LOGIN_RSP);
+			ret = LOGIN_VERSION_MISMATCH;
+			goto done;
+		} else if (pdu.opcode != ISCSI_OP_LOGIN_RSP) {
+			ret = LOGIN_INVALID_PDU;
+			goto done;
+		}
+
+		/*
+		 * give the caller the status class and detail from the last
+		 * login response PDU received
+		 */
+		if (status_class)
+			*status_class = login_rsp_pdu->status_class;
+		if (status_detail)
+			*status_detail = login_rsp_pdu->status_detail;
+		ret = check_status_login_response(session, login_rsp_pdu, data,
+						    max_data_length, &final);
+		if (final)
+			goto done;
+	} while (session->current_stage != ISCSI_FULL_FEATURE_PHASE);
+
+	ret = LOGIN_OK;
+
+ done:
+	if (auth_client && acl_finish(auth_client) != AUTH_STATUS_NO_ERROR) {
+		iscsi_host_err(session, "Login failed, error finishing "
+			       "auth_client\n");
+		if (ret == LOGIN_OK)
+			ret = LOGIN_FAILED;
+	}
+
+	return ret;
+}
diff -Naurp scsi-misc-2.6.orig/drivers/scsi/iscsi-sfnet/iscsi-login.h scsi-misc-2.6.patch/drivers/scsi/iscsi-sfnet/iscsi-login.h
--- scsi-misc-2.6.orig/drivers/scsi/iscsi-sfnet/iscsi-login.h	1969-12-31 16:00:00.000000000 -0800
+++ scsi-misc-2.6.patch/drivers/scsi/iscsi-sfnet/iscsi-login.h	2005-01-10 12:30:41.546574590 -0800
@@ -0,0 +1,84 @@
+/*
+ * iSCSI driver for Linux
+ * Copyright (C) 2001 Cisco Systems, Inc.
+ * maintained by linux-iscsi-devel@lists.sourceforge.net
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published
+ * by the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful, but
+ * WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
+ * General Public License for more details.
+ *
+ * See the file COPYING included with this distribution for more details.
+ *
+ * include for iSCSI login
+ */
+#ifndef ISCSI_LOGIN_H_
+#define ISCSI_LOGIN_H_
+
+struct iscsi_session;
+struct iscsi_hdr;
+
+#define ISCSI_SESSION_TYPE_NORMAL 0
+#define ISCSI_SESSION_TYPE_DISCOVERY 1
+
+/* not defined by iSCSI, but used in the login code to determine
+ * when to send the initial Login PDU
+ */
+#define ISCSI_INITIAL_LOGIN_STAGE -1
+
+#define ISCSI_TEXT_SEPARATOR     '='
+
+enum iscsi_login_status {
+	LOGIN_OK = 0,		/* library worked, but caller must check
+				 * the status class and detail
+				 */
+	LOGIN_IO_ERROR,		/* PDU I/O failed, connection have been
+				 * closed or reset
+				 */
+	LOGIN_FAILED,		/* misc. failure */
+	LOGIN_VERSION_MISMATCH,	/* incompatible iSCSI protocol version */
+	LOGIN_NEGOTIATION_FAILED,	/* didn't like a key value
+					 * (or received an unknown key)
+					 */
+	LOGIN_AUTHENTICATION_FAILED,	/* auth code indicated failure */
+	LOGIN_WRONG_PORTAL_GROUP,	/* portal group tag didn't match
+					 * the one required
+					 */
+	LOGIN_REDIRECTION_FAILED,	/* couldn't handle the redirection
+					 * requested by the target
+					 */
+	LOGIN_INVALID_PDU,	/* received an incorrect opcode,
+				 * or bogus fields in a PDU
+				 */
+};
+
+/* implemented in iscsi-login.c for use on all platforms */
+extern int iscsi_add_text(struct iscsi_session *session, struct iscsi_hdr *pdu,
+			  char *data, int max_data_length, char *param,
+			  char *value);
+extern enum iscsi_login_status iscsi_login(struct iscsi_session *session,
+					   char *buffer, size_t bufsize,
+					   uint8_t * status_class,
+					   uint8_t * status_detail);
+
+/* Digest types */
+#define ISCSI_DIGEST_NONE  0
+#define ISCSI_DIGEST_CRC32C 1
+#define ISCSI_DIGEST_CRC32C_NONE 2	/* offer both, prefer CRC32C */
+#define ISCSI_DIGEST_NONE_CRC32C 3	/* offer both, prefer None */
+
+#define IRRELEVANT_MAXCONNECTIONS	0x01
+#define IRRELEVANT_INITIALR2T		0x02
+#define IRRELEVANT_IMMEDIATEDATA	0x04
+#define IRRELEVANT_MAXBURSTLENGTH	0x08
+#define IRRELEVANT_FIRSTBURSTLENGTH	0x10
+#define IRRELEVANT_MAXOUTSTANDINGR2T	0x20
+#define IRRELEVANT_DATAPDUINORDER	0x40
+#define IRRELEVANT_DATASEQUENCEINORDER	0x80
+
+#endif