Bug 212136
| Summary: | Mismatch of allowed usernames between useradd and pam_unix | ||
|---|---|---|---|
| Product: | Red Hat Enterprise Linux 4 | Reporter: | Bastien Nocera <bnocera> |
| Component: | pam | Assignee: | Tomas Mraz <tmraz> |
| Status: | CLOSED ERRATA | QA Contact: | Jay Turner <jturner> |
| Severity: | medium | Docs Contact: | |
| Priority: | medium | ||
| Version: | 4.0 | CC: | linus.swalas, pvrabec, srevivo |
| Target Milestone: | --- | ||
| Target Release: | --- | ||
| Hardware: | All | ||
| OS: | Linux | ||
| Whiteboard: | |||
| Fixed In Version: | RHBA-2007-0300 | Doc Type: | Bug Fix |
| Doc Text: | Story Points: | --- | |
| Clone Of: | Environment: | ||
| Last Closed: | 2007-05-01 17:24:50 UTC | Type: | --- |
| Regression: | --- | Mount Type: | --- |
| Documentation: | --- | CRM: | |
| Verified Versions: | Category: | --- | |
| oVirt Team: | --- | RHEL 7.3 requirements from Atomic Host: | |
| Cloudforms Team: | --- | Target Upstream Version: | |
| Embargoed: | |||
Another option is to fix it on PAM side. Useradd allows [a-zA-Z0-9_.] as first character. We should allow the same in PAM. This request was evaluated by Red Hat Product Management for inclusion in a Red Hat Enterprise Linux maintenance release. Product Management has requested further review of this request by Red Hat Engineering, for potential inclusion in a Red Hat Enterprise Linux Update release for currently deployed products. This request is not yet committed for inclusion in an Update release. also luseradd supports "_ " as the first character of a user name. # luseradd _foo # echo $? 0 QE ack for 4.5. To be conformant with IEEE 1003.1-2004, and probable 2001 too, a username should
consist of characters from the "Portable Filename Character Set". The set
consists of all alphanumeric characters and ._-. (Dot, underscore and hyphen).
To be conformant, it should not begin with a hyphen.
For those of you who can't wait for a fix of this you can fix it
yourselves:
In pam_unix_passwd.c and pam_unix_auth.c you can replace the lines:
if (user == NULL || !isalnum(*user)) {
with:
if (user == NULL || (!isalnum(*user) && (*user !='_' && *user !='.'))) {
and then rebuild your PAM package.
An advisory has been issued which should help the problem described in this bug report. This report is therefore being closed with a resolution of ERRATA. For more information on the solution and/or where to find the updated files, please follow the link below. You may reopen this bug report if the solution does not work for you. http://rhn.redhat.com/errata/RHBA-2007-0300.html |
(This happens in FC6 and RHEL5 as well) # useradd _foo # passwd _foo Changing password for user _foo. passwd: Authentication token manipulation error From pam_unix_passwd.c: /* * First get the name of a user */ retval = pam_get_user(pamh, &user, "Username: "); if (retval == PAM_SUCCESS) { /* * Various libraries at various times have had bugs related to * '+' or '-' as the first character of a user name. Don't take * any chances here. Require that the username starts with an * alphanumeric character. */ if (user == NULL || !isalnum(*user)) { _log_err(LOG_ERR, pamh, "bad username [%s]", user); return PAM_USER_UNKNOWN; } useradd should be modified to allow the same usernames as pam_unix (or vice-versa).