[PATCH 4.12 046/196] iscsi-target: Add login_keys_workaround attribute for non RFC initiators

From: Greg Kroah-Hartman
Date: Tue Jul 25 2017 - 16:03:30 EST


4.12-stable review patch. If anyone has any objections, please let me know.

------------------

From: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>

commit 138d351eefb727ab9e41a3dc5f112ceb4f6e59f2 upstream.

This patch re-introduces part of a long standing login workaround that
was recently dropped by:

commit 1c99de981f30b3e7868b8d20ce5479fa1c0fea46
Author: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Date: Sun Apr 2 13:36:44 2017 -0700

iscsi-target: Drop work-around for legacy GlobalSAN initiator

Namely, the workaround for FirstBurstLength ended up being required by
Mellanox Flexboot PXE boot ROMs as reported by Robert.

So this patch re-adds the work-around for FirstBurstLength within
iscsi_check_proposer_for_optional_reply(), and makes the key optional
to respond when the initiator does not propose, nor respond to it.

Also as requested by Arun, this patch introduces a new TPG attribute
named 'login_keys_workaround' that controls the use of both the
FirstBurstLength workaround, as well as the two other existing
workarounds for gPXE iSCSI boot client.

By default, the workaround is enabled with login_keys_workaround=1,
since Mellanox FlexBoot requires it, and Arun has verified the Qlogic
MSFT initiator already proposes FirstBurstLength, so it's uneffected
by this re-adding this part of the original work-around.

Reported-by: Robert LeBlanc <robert@xxxxxxxxxxxxx>
Cc: Robert LeBlanc <robert@xxxxxxxxxxxxx>
Reviewed-by: Arun Easi <arun.easi@xxxxxxxxxx>
Signed-off-by: Nicholas Bellinger <nab@xxxxxxxxxxxxxxx>
Signed-off-by: Greg Kroah-Hartman <gregkh@xxxxxxxxxxxxxxxxxxx>

---
drivers/target/iscsi/iscsi_target_configfs.c | 2 +
drivers/target/iscsi/iscsi_target_nego.c | 6 ++-
drivers/target/iscsi/iscsi_target_parameters.c | 41 +++++++++++++++++--------
drivers/target/iscsi/iscsi_target_parameters.h | 2 -
drivers/target/iscsi/iscsi_target_tpg.c | 19 +++++++++++
drivers/target/iscsi/iscsi_target_tpg.h | 1
include/target/iscsi/iscsi_target_core.h | 9 +++++
7 files changed, 64 insertions(+), 16 deletions(-)

--- a/drivers/target/iscsi/iscsi_target_configfs.c
+++ b/drivers/target/iscsi/iscsi_target_configfs.c
@@ -781,6 +781,7 @@ DEF_TPG_ATTRIB(default_erl);
DEF_TPG_ATTRIB(t10_pi);
DEF_TPG_ATTRIB(fabric_prot_type);
DEF_TPG_ATTRIB(tpg_enabled_sendtargets);
+DEF_TPG_ATTRIB(login_keys_workaround);

static struct configfs_attribute *lio_target_tpg_attrib_attrs[] = {
&iscsi_tpg_attrib_attr_authentication,
@@ -796,6 +797,7 @@ static struct configfs_attribute *lio_ta
&iscsi_tpg_attrib_attr_t10_pi,
&iscsi_tpg_attrib_attr_fabric_prot_type,
&iscsi_tpg_attrib_attr_tpg_enabled_sendtargets,
+ &iscsi_tpg_attrib_attr_login_keys_workaround,
NULL,
};

--- a/drivers/target/iscsi/iscsi_target_nego.c
+++ b/drivers/target/iscsi/iscsi_target_nego.c
@@ -886,7 +886,8 @@ static int iscsi_target_handle_csg_zero(
SENDER_TARGET,
login->rsp_buf,
&login->rsp_length,
- conn->param_list);
+ conn->param_list,
+ conn->tpg->tpg_attrib.login_keys_workaround);
if (ret < 0)
return -1;

@@ -956,7 +957,8 @@ static int iscsi_target_handle_csg_one(s
SENDER_TARGET,
login->rsp_buf,
&login->rsp_length,
- conn->param_list);
+ conn->param_list,
+ conn->tpg->tpg_attrib.login_keys_workaround);
if (ret < 0) {
iscsit_tx_login_rsp(conn, ISCSI_STATUS_CLS_INITIATOR_ERR,
ISCSI_LOGIN_STATUS_INIT_ERR);
--- a/drivers/target/iscsi/iscsi_target_parameters.c
+++ b/drivers/target/iscsi/iscsi_target_parameters.c
@@ -765,7 +765,8 @@ static int iscsi_check_for_auth_key(char
return 0;
}

-static void iscsi_check_proposer_for_optional_reply(struct iscsi_param *param)
+static void iscsi_check_proposer_for_optional_reply(struct iscsi_param *param,
+ bool keys_workaround)
{
if (IS_TYPE_BOOL_AND(param)) {
if (!strcmp(param->value, NO))
@@ -773,19 +774,31 @@ static void iscsi_check_proposer_for_opt
} else if (IS_TYPE_BOOL_OR(param)) {
if (!strcmp(param->value, YES))
SET_PSTATE_REPLY_OPTIONAL(param);
- /*
- * Required for gPXE iSCSI boot client
- */
- if (!strcmp(param->name, IMMEDIATEDATA))
- SET_PSTATE_REPLY_OPTIONAL(param);
+
+ if (keys_workaround) {
+ /*
+ * Required for gPXE iSCSI boot client
+ */
+ if (!strcmp(param->name, IMMEDIATEDATA))
+ SET_PSTATE_REPLY_OPTIONAL(param);
+ }
} else if (IS_TYPE_NUMBER(param)) {
if (!strcmp(param->name, MAXRECVDATASEGMENTLENGTH))
SET_PSTATE_REPLY_OPTIONAL(param);
- /*
- * Required for gPXE iSCSI boot client
- */
- if (!strcmp(param->name, MAXCONNECTIONS))
- SET_PSTATE_REPLY_OPTIONAL(param);
+
+ if (keys_workaround) {
+ /*
+ * Required for Mellanox Flexboot PXE boot ROM
+ */
+ if (!strcmp(param->name, FIRSTBURSTLENGTH))
+ SET_PSTATE_REPLY_OPTIONAL(param);
+
+ /*
+ * Required for gPXE iSCSI boot client
+ */
+ if (!strcmp(param->name, MAXCONNECTIONS))
+ SET_PSTATE_REPLY_OPTIONAL(param);
+ }
} else if (IS_PHASE_DECLARATIVE(param))
SET_PSTATE_REPLY_OPTIONAL(param);
}
@@ -1422,7 +1435,8 @@ int iscsi_encode_text_output(
u8 sender,
char *textbuf,
u32 *length,
- struct iscsi_param_list *param_list)
+ struct iscsi_param_list *param_list,
+ bool keys_workaround)
{
char *output_buf = NULL;
struct iscsi_extra_response *er;
@@ -1458,7 +1472,8 @@ int iscsi_encode_text_output(
*length += 1;
output_buf = textbuf + *length;
SET_PSTATE_PROPOSER(param);
- iscsi_check_proposer_for_optional_reply(param);
+ iscsi_check_proposer_for_optional_reply(param,
+ keys_workaround);
pr_debug("Sending key: %s=%s\n",
param->name, param->value);
}
--- a/drivers/target/iscsi/iscsi_target_parameters.h
+++ b/drivers/target/iscsi/iscsi_target_parameters.h
@@ -46,7 +46,7 @@ extern int iscsi_extract_key_value(char
extern int iscsi_update_param_value(struct iscsi_param *, char *);
extern int iscsi_decode_text_input(u8, u8, char *, u32, struct iscsi_conn *);
extern int iscsi_encode_text_output(u8, u8, char *, u32 *,
- struct iscsi_param_list *);
+ struct iscsi_param_list *, bool);
extern int iscsi_check_negotiated_keys(struct iscsi_param_list *);
extern void iscsi_set_connection_parameters(struct iscsi_conn_ops *,
struct iscsi_param_list *);
--- a/drivers/target/iscsi/iscsi_target_tpg.c
+++ b/drivers/target/iscsi/iscsi_target_tpg.c
@@ -227,6 +227,7 @@ static void iscsit_set_default_tpg_attri
a->t10_pi = TA_DEFAULT_T10_PI;
a->fabric_prot_type = TA_DEFAULT_FABRIC_PROT_TYPE;
a->tpg_enabled_sendtargets = TA_DEFAULT_TPG_ENABLED_SENDTARGETS;
+ a->login_keys_workaround = TA_DEFAULT_LOGIN_KEYS_WORKAROUND;
}

int iscsit_tpg_add_portal_group(struct iscsi_tiqn *tiqn, struct iscsi_portal_group *tpg)
@@ -899,3 +900,21 @@ int iscsit_ta_tpg_enabled_sendtargets(

return 0;
}
+
+int iscsit_ta_login_keys_workaround(
+ struct iscsi_portal_group *tpg,
+ u32 flag)
+{
+ struct iscsi_tpg_attrib *a = &tpg->tpg_attrib;
+
+ if ((flag != 0) && (flag != 1)) {
+ pr_err("Illegal value %d\n", flag);
+ return -EINVAL;
+ }
+
+ a->login_keys_workaround = flag;
+ pr_debug("iSCSI_TPG[%hu] - TPG enabled bit for login keys workaround: %s ",
+ tpg->tpgt, (a->login_keys_workaround) ? "ON" : "OFF");
+
+ return 0;
+}
--- a/drivers/target/iscsi/iscsi_target_tpg.h
+++ b/drivers/target/iscsi/iscsi_target_tpg.h
@@ -48,5 +48,6 @@ extern int iscsit_ta_default_erl(struct
extern int iscsit_ta_t10_pi(struct iscsi_portal_group *, u32);
extern int iscsit_ta_fabric_prot_type(struct iscsi_portal_group *, u32);
extern int iscsit_ta_tpg_enabled_sendtargets(struct iscsi_portal_group *, u32);
+extern int iscsit_ta_login_keys_workaround(struct iscsi_portal_group *, u32);

#endif /* ISCSI_TARGET_TPG_H */
--- a/include/target/iscsi/iscsi_target_core.h
+++ b/include/target/iscsi/iscsi_target_core.h
@@ -66,6 +66,14 @@ struct sock;
#define TA_DEFAULT_FABRIC_PROT_TYPE 0
/* TPG status needs to be enabled to return sendtargets discovery endpoint info */
#define TA_DEFAULT_TPG_ENABLED_SENDTARGETS 1
+/*
+ * Used to control the sending of keys with optional to respond state bit,
+ * as a workaround for non RFC compliant initiators,that do not propose,
+ * nor respond to specific keys required for login to complete.
+ *
+ * See iscsi_check_proposer_for_optional_reply() for more details.
+ */
+#define TA_DEFAULT_LOGIN_KEYS_WORKAROUND 1

#define ISCSI_IOV_DATA_BUFFER 5

@@ -769,6 +777,7 @@ struct iscsi_tpg_attrib {
u8 t10_pi;
u32 fabric_prot_type;
u32 tpg_enabled_sendtargets;
+ u32 login_keys_workaround;
struct iscsi_portal_group *tpg;
};