Package: netkit-rsh
Version: 0.17-14
Severity: wishlist
Tags: patch
Hi,
I am using a linux server with an application accessed via rexec from
many windows clients. These clients aren't recorded in any DNS, and
obtain their IP addresses vi dhcp.
The current rexecd implementation in netkit require client to be
registered in a DNS, otherwise print error "Where are you?". AIX version
on rexecd has an option, -c, that skip this control, and accept any
client. (The AIX manual page is available here:
http://www.ncsa.uiuc.edu/UserInfo/Resources/Hardware/IBMp690/IBM/usr/share/man/info/en_US/a_doc_lib/cmds/aixcmds4/rexecd.htm)
I wrote a patch for adding this option to the netkit implementation
(both code and manual page). I would like to submit it for inclusion in
the Debian package.
Thanks a lot,
Giuseppe
diff -ruN netkit-rsh-0.17/rexecd/rexecd.8 netkit-rsh-0.17.new/rexecd/rexecd.8
--- netkit-rsh-0.17/rexecd/rexecd.8 2000-07-31 01:57:04.000000000 +0200
+++ netkit-rsh-0.17.new/rexecd/rexecd.8 2008-02-07 10:41:40.000000000 +0100
@@ -39,7 +39,7 @@
.Nm rexecd
.Nd remote execution server
.Sh SYNOPSIS
-.Nm rexecd
+.Nm rexecd [\-c]
.Sh DESCRIPTION
.Nm Rexecd
is the server for the
@@ -56,6 +56,12 @@
is initiated:
.Bl -enum
.It
+The server verify that the client has a valid hostname
+associated in DNS, unless option \fB\-c\fP is specified.
+If the client machine isn't accepted at this stage, the
+error message 'Where are you?' is returned to the client
+machine.
+.It
The server reads characters from the socket up
to a NUL
.Pq Ql \e0
@@ -64,7 +70,7 @@
.Tn ASCII
number, base 10.
.It
-If the number received in step 1 is non-zero,
+If the number received in step 2 is non-zero,
it is interpreted as the port number of a secondary
stream to be used for the
.Em stderr .
diff -ruN netkit-rsh-0.17/rexecd/rexecd.c netkit-rsh-0.17.new/rexecd/rexecd.c
--- netkit-rsh-0.17/rexecd/rexecd.c 2008-02-07 10:43:16.000000000 +0100
+++ netkit-rsh-0.17.new/rexecd/rexecd.c 2008-02-07 10:20:51.000000000 +0100
@@ -120,8 +120,10 @@
struct sockaddr_storage from;
struct sockaddr *const fromp = (void *)&from;
socklen_t fromlen;
+ int namerequired = 1;
- (void)argc;
+ if (argc>1)
+ namerequired = strcmp("-c", argv[1]);
fromlen = sizeof(from);
@@ -150,9 +152,21 @@
#else
{
char hbuf[NI_MAXHOST];
+ int i;
- if (getnameinfo(fromp, fromlen,
- hbuf, sizeof(hbuf), NULL, 0, NI_NAMEREQD)) {
+ i = getnameinfo(fromp, fromlen,
+ hbuf, sizeof(hbuf), NULL, 0, NI_NAMEREQD);
+ if (i && !namerequired) {
+ long unsigned int ad4 = ((struct sockaddr_in *)fromp)->sin_addr.s_addr;
+ if (from.ss_family == AF_INET6)
+ syslog(LOG_ERR, "getnameinfo(family=AF_INET6) failed with code %d (%s).", i, gai_strerror(i));
+ else {
+ sprintf(hbuf,"%lu.%lu.%lu.%lu", ad4&0xff, (ad4>>8)&0xff, (ad4>>16)&0xff, (ad4>>24)&0xff);
+ i = getnameinfo(fromp, fromlen, hbuf, sizeof(hbuf), NULL, 0, 0);
+ }
+ }
+
+ if (i) {
write(0, "\1Where are you?\n", 16);
return 1;
}
