svcadm(8)을 검색하려면 섹션에서 8 을 선택하고, 맨 페이지 이름에 svcadm을 입력하고 검색을 누른다.
rshd(8)
System Administration Commands in.rshd(8)
NAME
in.rshd, rshd - remote shell server
SYNOPSIS
in.rshd [-k5eciU] [-s tos] [-S keytab] [-M realm]
[-L env_var] host.port
DESCRIPTION
in.rshd is the server for the rsh(1) program. The server provides
remote execution facilities with authentication based on Kerberos V5 or
privileged port numbers.
in.rshd is invoked by inetd(8) each time a shell service is requested.
When Kerberos V5 authentication is required (this can be set with Ker‐
beros-specific options listed below), the following protocol is initi‐
ated:
1. Check Kerberos V5 authentication.
2. Check the authorization rules.
3. A null byte is returned on the initial socket and the com‐
mand line is passed to the normal login shell of the user.
(The PATH variable is set to /usr/bin.) The shell inherits
the network connections established by in.rshd.
In order for Kerberos authentication to work, a host/<FQDN> Kerberos
principal must exist for each Fully Qualified Domain Name associated
with the in.rshd server. Each of these host/<FQDN> principals must have
a keytab entry in the /etc/krb5/krb5.keytab file on the in.rshd server.
An example principal might be:
host/bigmachine.eng.example.com
See kadmin for instructions on adding a principal to a krb5.keytab
file.
If Kerberos V5 authentication is not enabled, then in.rshd executes the
following protocol:
1. The server checks the client's source port. If the port is
not in the range 512-1023, the server aborts the connection.
The client's host address (in hex) and port number (in deci‐
mal) are the arguments passed to in.rshd.
2. The server reads characters from the socket up to a null
(\0) byte. The resultant string is interpreted as an ASCII
number, base 10.
3. If the number received in step 2 is non-zero, it is inter‐
preted as the port number of a secondary stream to be used
for the stderr. A second connection is then created to the
specified port on the client's machine. The source port of
this second connection is also in the range 512-1023.
4. A null-terminated user name of at most 256 characters is
retrieved on the initial socket. This user name is inter‐
preted as the user identity on the client's machine.
5. A null terminated user name of at most 256 characters is
retrieved on the initial socket. This user name is inter‐
preted as a user identity to use on the server's machine.
6. A null terminated command to be passed to a shell is
retrieved on the initial socket. The length of the command
is limited by the upper bound on the size of the system's
argument list.
7. in.rshd then validates the user according to the following
steps. The remote user name is looked up in the password
file and a chdir is performed to the user's home directory.
If the lookup fails, the connection is terminated. If the
chdir fails, it does a chdir to / (root). If the user is not
the superuser, (user ID 0), and if the pam_rhosts_auth PAM
module is configured for authentication, the file
/etc/hosts.equiv is consulted for a list of hosts considered
"equivalent". If the client's host name is present in this
file, the authentication is considered successful. See the
SECURITY section below for a discussion of PAM authentica‐
tion.
If the lookup fails, or the user is the superuser, then the
file .rhosts in the home directory of the remote user is
checked for the machine name and identity of the user on the
client's machine. If this lookup fails, the connection is
terminated
8. A null byte is returned on the initial connection and the
command line is passed to the normal login shell of the
user. The PATH variable is set to /usr/bin. The shell inher‐
its the network connections established by in.rshd.
OPTIONS
The following options are supported:
-L env_var List of environment variables that need to be saved and
passed along.
-s tos Sets the IP TOS option.
-U Refuses connections that cannot be mapped to a name
through the getnameinfo(3C) function.
USAGE
rshd and in.rshd are IPv6-enabled. See ip6(4P). IPv6 is not currently
supported with Kerberos V5 authentication.
The Kerberized rshd service runs on port 544 (kshell). The correspond‐
ing FMRI entry is: :
svc:/network/shell:kshell (rshd with kerberos (ipv4 only))
SECURITY
in.rshd uses pam(3PAM) for authentication, account management, and ses‐
sion management. The PAM configuration policy, configured in
/etc/pam.conf or per-service files in /etc/pam.d/, specifies the mod‐
ules to be used for in.rshd. Here is a partial pam.conf file with
entries for the rsh command using rhosts authentication, UNIX account
management, and session management module.
tab(); lw(0.7i) lw(0.7i) lw(0.82i) lw(3.28i) rshauthrequired‐
pam_rhosts_auth.so.1
rshaccountrequiredpam_unix_roles.so.1 rshsessionrequired‐
pam_unix_projects.so.1 rshsessionrequiredpam_unix_account.so.1
rshsessionrequiredpam_unix_session.so.1
The equivalent PAM configuration using /etc/pam.d/ would be the follow‐
ing entries in /etc/pam.d/rsh:
auth required pam_rhosts_auth.so.1
account required pam_unix_roles.so.1
session required pam_unix_projects.so.1
session required pam_unix_account.so.1
session required pam_unix_session.so.1
If there are no entries for the rsh service in /etc/pam.conf and
/etc/pam.d/rsh does not exist then the entries for the "other" service
in /etc/pam.conf are used. If there are not any entries in
/etc/pam.conf for the "other", then the entries in /etc/pam.d/other
will be used. To maintain the authentication requirement for in.rshd,
the rsh entry must always be configured with the pam_rhosts_auth.so.1
module.
in.rshd can authenticate using Kerberos V5 authentication or pam(3PAM).
For Kerberized rsh service, the appropriate PAM service name is krsh.
FILES
/etc/hosts.equiv
$HOME/.k5login File containing Kerberos principals that are
allowed access.
/etc/krb5/krb5.conf Kerberos configuration file.
ATTRIBUTES
See attributes(7) for descriptions of the following attributes:
tab() box; cw(2.75i) |cw(2.75i) lw(2.75i) |lw(2.75i) ATTRIBUTE TYPEAT‐
TRIBUTE VALUE _ Availabilityservice/network/legacy-remote-utilities _
Interface StabilityObsolete
SEE ALSO
rsh(1), svcs(1), getnameinfo(3C), pam(3PAM), ip6(4P), hosts(5),
pam.conf(5), attributes(7), environ(7), krb5_auth_rules(7), pam_auth‐
tok_check(7), pam_authtok_get(7), pam_authtok_store(7), pam_dhkeys(7),
pam_passwd_auth(7), pam_rhosts_auth(7), pam_unix_account(7),
pam_unix_auth(7), pam_unix_session(7), smf(7), inetadm(8), inetd(8),
svcadm(8)
DIAGNOSTICS
The following diagnostic messages are returned on the connection asso‐
ciated with stderr, after which any network connections are closed. An
error is indicated by a leading byte with a value of 1 in step 8 above
(0 is returned above upon successful completion of all the steps prior
to the command execution).
locuser too long
The name of the user on the client's machine is longer than 256
characters.
remuser too long
The name of the user on the remote machine is longer than 256 char‐
acters.
command too long
The command line passed exceeds the size of the argument list (as
configured into the system).
Hostname for your address unknown.
No entry in the host name database existed for the client's
machine.
Login incorrect.
No password file entry for the user name existed.
Permission denied.
The authentication procedure described above failed.
Can't make pipe.
The pipe needed for the stderr was not created.
Try again.
A fork by the server failed.
NOTES
The authentication procedure used here assumes the integrity of each
client machine and the connecting medium. This is insecure, but it is
useful in an "open" environment.
A facility to allow all data exchanges to be encrypted should be
present.
The in.rshd service is managed by the service management facility,
smf(7), under the service identifier:
svc:/network/shell:default
Administrative actions on this service, such as enabling, disabling, or
requesting restart, can be performed using svcadm(8). Responsibility
for initiating and restarting this service is delegated to inetd(8).
Use inetadm(8) to make configuration changes and to view configuration
information for this service. The service's status can be queried using
the svcs(1) command.
This technology may be removed in a future release of Oracle Solaris.
Oracle Solaris 11.4 22 Feb 2017 in.rshd(8)