iscsi-target: ST response on IN6ADDR_ANY socket

Odd little issue, found that if you create an IPv6 portal bound to the
IN6ADDR_ANY wildcard address it will accept IPv4 connections (as long as
bindv6only isn't set globally) but respond to SendTargets requests with
an IPv4-mapped IPv6 address.

Example over loopback:

 In targetcli create a wildcard IPv6 portal
   /iscsi/iqn.../portals/> create ::
 Which should create a portal [::]:3260

 Initiate SendTargets discovery to the portal using an IPv4 address
   # iscsiadm -m discovery -t st -p 127.0.0.1
 The response formats TargetAddress as [::ffff:127.0.0.1]:3260,1

This still works and uses v4 on the network between two v6 sockets, but
only if the initiator supports IPv6 with v4-mapped addresses.

This change detects v4-mapped address on v6 sockets for the wildcard
case, and instead formats the TargetAddress response as an IPv4 address.

In order to not further complicate iscsit_build_sendtargets_response,
I've actually simplified it by moving the bracket wrapping of IPv6
address into iscsit_accept_np where local_ip and login_ip strings are
set.  That also simplifies iscsi_stat_tgt_attr_show_attr_fail_intr_addr.

Side effect of the string format change is that
lio_target_nacl_show_info will now print login_ip bracket wrapped for
IPv6 connections, as will a few debug prints.

Signed-off-by: Chris Leech <cleech@redhat.com>
Signed-off-by: Nicholas Bellinger <nab@linux-iscsi.org>
This commit is contained in:
Chris Leech 2013-08-12 11:26:28 -07:00 committed by Nicholas Bellinger
parent de04a8aa6b
commit dfecf611a1
3 changed files with 16 additions and 16 deletions

View File

@ -3444,12 +3444,10 @@ static int iscsit_build_sendtargets_response(struct iscsi_cmd *cmd)
bool inaddr_any = iscsit_check_inaddr_any(np);
len = sprintf(buf, "TargetAddress="
"%s%s%s:%hu,%hu",
(np->np_sockaddr.ss_family == AF_INET6) ?
"[" : "", (inaddr_any == false) ?
"%s:%hu,%hu",
(inaddr_any == false) ?
np->np_ip : conn->local_ip,
(np->np_sockaddr.ss_family == AF_INET6) ?
"]" : "", (inaddr_any == false) ?
(inaddr_any == false) ?
np->np_port : conn->local_port,
tpg->tpgt);
len += 1;

View File

@ -1007,16 +1007,24 @@ int iscsit_accept_np(struct iscsi_np *np, struct iscsi_conn *conn)
rc = conn->sock->ops->getname(conn->sock,
(struct sockaddr *)&sock_in6, &err, 1);
if (!rc) {
snprintf(conn->login_ip, sizeof(conn->login_ip), "%pI6c",
&sock_in6.sin6_addr.in6_u);
if (!ipv6_addr_v4mapped(&sock_in6.sin6_addr))
snprintf(conn->login_ip, sizeof(conn->login_ip), "[%pI6c]",
&sock_in6.sin6_addr.in6_u);
else
snprintf(conn->login_ip, sizeof(conn->login_ip), "%pI4",
&sock_in6.sin6_addr.s6_addr32[3]);
conn->login_port = ntohs(sock_in6.sin6_port);
}
rc = conn->sock->ops->getname(conn->sock,
(struct sockaddr *)&sock_in6, &err, 0);
if (!rc) {
snprintf(conn->local_ip, sizeof(conn->local_ip), "%pI6c",
&sock_in6.sin6_addr.in6_u);
if (!ipv6_addr_v4mapped(&sock_in6.sin6_addr))
snprintf(conn->local_ip, sizeof(conn->local_ip), "[%pI6c]",
&sock_in6.sin6_addr.in6_u);
else
snprintf(conn->local_ip, sizeof(conn->local_ip), "%pI4",
&sock_in6.sin6_addr.s6_addr32[3]);
conn->local_port = ntohs(sock_in6.sin6_port);
}
} else {

View File

@ -432,13 +432,7 @@ static ssize_t iscsi_stat_tgt_attr_show_attr_fail_intr_addr(
int ret;
spin_lock(&lstat->lock);
if (lstat->last_intr_fail_ip_family == AF_INET6) {
ret = snprintf(page, PAGE_SIZE, "[%s]\n",
lstat->last_intr_fail_ip_addr);
} else {
ret = snprintf(page, PAGE_SIZE, "%s\n",
lstat->last_intr_fail_ip_addr);
}
ret = snprintf(page, PAGE_SIZE, "%s\n", lstat->last_intr_fail_ip_addr);
spin_unlock(&lstat->lock);
return ret;