DPRINTF was blindly sending all debug output to fd 2 (stderr).
The new function iscsi_set_debug_fd() will set the debug fd.
In general debugging is completely disabled by default.
qemu-kvm calls iscsi_parse_url_full() with iscsi = NULL.
In case there is an invalid URL specified qemu-kvm segfaults when
it tries to set iscsi->error_string.
I tried to patch this in qemu-kvm, but the initiator_name is dirived
from the target name so this seemed to be the easier approach.
The iscsi_url and iscsi_context might contain clear text
login credentials for an iscsi target. As Linux zeroes
on allocate this data might remain in memory for a long
time.
This patch adds a wrapper around all memory allocations and frees.
The idea is to get warned immediately if the application leaks memory.
Additionally the wrapper functions make it easy to add different
memory allocators or memory pools in the future.
gcc-4.6.3 reports these:
libtool: compile: gcc -DHAVE_CONFIG_H -I. -I. -I./include "-D_U_=__attribute__((unused))" -Wall -W -Wshadow -Wstrict-prototypes -Wpointer-arith -Wcast-align -Wwrite-strings -g -O2 -MT lib/init.lo -MD -MP -MF lib/.deps/init.Tpo -c lib/init.c -fPIC -DPIC -o lib/.libs/init.o
lib/init.c: In function 'iscsi_parse_url':
lib/init.c:410:18: warning: 'l' may be used uninitialized in this function [-Wuninitialized]
lib/init.c:409:10: warning: 'target' may be used uninitialized in this function [-Wuninitialized]
Both warnings appear to be spurious though, as both "target" and "l" are only used if
"full" is set, which implies that these are initialized before.
Signed-off-by: Arne Redlich <arne.redlich@googlemail.com>
This patch adds support for setting TCP_SYNCNT to overwrite
the system default values. This allows indirect support
for a configurable connect timeout.
Linux uses a exponential backoff for SYN retries starting
with 1 second.
This means for a value n for TCP_SYNCNT, the connect will
effectively timeout after 2^(n+1)-1 seconds.
This patch allows the following parameters inside libiscsi to be adjusted without code modification:
LIBISCSI_DEBUG
LIBISCSI_TCP_USER_TIMEOUT
LIBISCSI_TCP_KEEPIDLE
LIBISCSI_TCP_KEEPCNT
LIBISCSI_TCP_KEEPINTVL
You can now enable debugging of libiscsi inside e.g. qemu-kvm with
LIBISCSI_DEBUG=3 qemu-kvm -hda iscsi://...
This patch adds 3 functions to set the 3 keepalive values TCP_KEEPIDLE, TCP_KEEPCNT
and TCP_KEEPINTVL. The values have to be set after iscsi context creation and are
then configured on the socket on each new connection.
"random" ISID randomly.
Dont assume that users will never create multiple contexts
concurrently, in which case the previous getpid()^time(NULL)
would create duplicates.
A Portal URL is of the form
iscsi://[<username>[%<password>]@]<host>[:<port>]
and is used by command such as iscsi-ls during the discovery login phase.
During discovery we do not yet know the target iqn name, nor the lun of
any devices.
There is no point in setting the username if there is no password
and vice versa.
Also, if we only set username but not passwd this would lead to a segv.
so that the password will not be showing up in log where the application
logs the "filename/iscsi url" or in ps aux output.
LIBISCSI_CHAP_USERNAME and LIBISCSI_CHAP_PASSWORD environment variables are
available to set these outside of the url.
If hte username/password is ALSO set in the URL, the settings in the URL
will override the environment variables.
This flag is used when we dont want the CANCEL callback to be invoked if the
context is destroyed.
Thsi will be used for the sequence where we send multiple PDUs
to the target for one single scsi task, such as
-> WRITE10 cdb
-> DATAOUT
-< RESPONSE
Since if the context is destroyed when the command is in flight, we
already get the CANCEL callback for the WRITE10 PDU, so we dont need to invoke
it again for when we destroy the DATAOUT pdu, since they both refer to the same
task.
We will use this later to decide when we should send unsolicited imemdiate
data to the target. Currently we always send unsolicited immediate data
but targets configured to not allow immediate data may refuce this and
turn an error.
and accept what Target responds.
Store the result of the negotiated setting in the iscsi context
so we can use it later to determine how to send solicited/unsolicited
data.
Always print the correct url syntax when parsing has failed.
Test if the user forgot to specify a <target-iqn> at all and log
this as a missing target-iqn error. Not as a missing <lun> error.
Remove \n from the error strings in init.c
Add these settings to the iscsi context structure and initialize them to
sane valued.
When sending login commands to the target, use these values instead
of hardcoded values.
Parse when the target sends a login reply back to us and update these variables
if the target asks us to.
This allows us to detect when our defaults are too big for the target
and adjust the settings we use so we match the target.
Some targets have a very small accepted default for some settings.
During login, we will initially send these keys with our dafult values.
These targets will then respond back by refusing to transition to the next
login phase, and by telling us back what the maximum of these values should be.
In this case we have to try the login again but use the smaller values we got
from the target.
Othervise, if we try again, ignoring the value from the target, and just repeat
using our defaults the target will abort the login with a "initiator error".
Add unidirectional chap support so we can authenticate to the target.
Make the login phase more "intelligent" so we can iterate over login
pdus until we have reached full feature phase
Add a new helper functions to parse a iscsi url and break it down
into elements in a structure
Update iscsi-inq to allow CHAP authentication
