Re: [Qemu-devel] [PATCH] iscsi: Add chap and "initiator-name" etc as per drive options

[ronnie sahlberg]

On Fri, Sep 11, 2015 at 8:20 AM, Eric Blake <address@hidden> wrote:
> On 09/11/2015 12:00 AM, Fam Zheng wrote:
>> Previously we use "-iscsi id=target-iqn,user=foo,password=bar,..." to
>> specify iscsi connection parameters, unfortunately it doesn't work with
>> qemu-img.
>>
>> This patch adds per drive options to iscsi driver so that at least
>> qemu-img can use the "json:{...}" filename magic.
>>
>> Signed-off-by: Fam Zheng <address@hidden>
>> ---
>>  block/iscsi.c | 83 
>> +++++++++++++++++++++++++++++++++++++++++++++--------------
>>  1 file changed, 64 insertions(+), 19 deletions(-)
>
> It would be nice to also add a matching BlockdevOptionsIscsi to
> qapi/block-core.json, to allow setting these structured options from
> QMP.  Separate patch is fine, but we need to do the work for ALL of the
> remaining block devices eventually, and now that you are structuring the
> command line is a good time to think about it.
>
>
>>  static void iscsi_nop_timed_event(void *opaque)
>> @@ -1229,6 +1253,27 @@ static QemuOptsList runtime_opts = {
>>              .name = "filename",
>>              .type = QEMU_OPT_STRING,
>>              .help = "URL to the iscsi image",
>> +        },{
>> +            .name = "user",
>> +            .type = QEMU_OPT_STRING,
>> +            .help = "username for CHAP authentication to target",
>> +        },{
>> +            .name = "password",
>> +            .type = QEMU_OPT_STRING,
>> +            .help = "password for CHAP authentication to target",
>> +        },{
>
> Also, this requires passing the password in the command line. We
> _really_ need to solve the problem of allowing the password to be passed
> via a fd or other QMP command, rather than on the command line.


Passing via command line is evil. It should still be possible to pass
all this via a config file to qemu :

"""
...
Howto use a configuration file to set iSCSI configuration options:
@example
cat >iscsi.conf <<EOF
[iscsi "iqn.target.name"]
  user = "me"
  password = "my password"
  initiator-name = "iqn.qemu.test:my-initiator"
  header-digest = "CRC32C"
EOF

qemu-system-i386 -drive file=iscsi://127.0.0.1/iqn.qemu.test/1 \
    -readconfig iscsi.conf
@end example
...
"""





>
> --
> Eric Blake   eblake redhat com    +1-919-301-3266
> Libvirt virtualization library http://libvirt.org
>