Username and Groupname Sizes on HP-UX

ManualsBrandsHP ManualsSoftwareHP-UX 11i v3 Foundation OE

1.0 Introduction .............................................................................................................................2

2.0 Enabling the System for expanded User and Group names ..............................................................3

3.0 Output Formats.........................................................................................................................3

3.1 Issues due to Display of Long User/Group Names.......................................................................4

3.2 Display Guidelines Followed by HP Supplied Commands and Utilities............................................4

3.2.1 Default Display Mode......................................................................................................4

3.2.2 System-wide or user specific configuration of display width....................................................4

3.3 API for Display Width ............................................................................................................4

3.4 Types of Applications That Need to Consider the Display Guidelines..............................................4

3.5 Type of Applications that need not consider the Display Guidelines ...............................................5

4.0 HP Product Limitations................................................................................................................5

4.1 SNA user and administration...................................................................................................5

4.2 Trusted mode........................................................................................................................5

5.0 Programmer Notes....................................................................................................................5

5.1 Checklist to Find out Whether Your Program is Long User/Group Name Clean and Methods to Make

Them Clean ...............................................................................................................................6

5.2 Other Considerations.............................................................................................................7

5.2.1 Dependency on the system state: Expanded user/group name enabled or not...........................7

6 Test Guidelines............................................................................................................................7

6.1 User/Group Database Configuration........................................................................................7

6.2 Display Functionality..............................................................................................................7

6.3 Buffer Overflow tests..............................................................................................................8

7.0 Summary.................................................................................................................................8

Glossary of Terms...........................................................................................................................8

Summary of content (8 pages)

PAGE 1
Username and Groupname Sizes on HP-UX 1.0 Introduction ............................................................................................................................. 2 2.0 Enabling the System for expanded User and Group names .............................................................. 3 3.0 Output Formats......................................................................................................................... 3 3.1 Issues due to Display of Long User/Group Names.............
PAGE 2
ABSTRACT HP-UX 11i Version 3 provides expanded username and groupname interfaces. This capability allows setting of user and group names that are longer than the previously supported value. HP provides this enhancement to support the user/group naming requirements of some customers. The default operating system configuration settings ensure compatibility for applications using user and group names by enforcing compatible name sizes.
PAGE 3
Testing Guidelines: Describes briefly how to test an application to ensure that it works well in an expanded user and group name enabled environment. 2.0 Enabling the System for expanded User and Group names This section describes how an administrator enables the capability to set longer user and group names.
PAGE 4
3.1 Issues due to Display of Long User/Group Names • • • • • Extending user/group names beyond 8 bytes disrupts the tabular output of commands such as ps that do not truncate user/group names. Commands such as ls that truncate user/group names provide incomplete/erroneous data to callers. Script writers often use the knowledge of the column widths of different fields in the output by commands such as ls. This gathered data is then used to perform some other action.
PAGE 5
• Applications that may have their output parsed by other applications, but do not clearly define rules for parsing the output. 3.5 Type of Applications that need not consider the Display Guidelines The following applications need not consider the formatting rules: • Applications that do not display user or group names. • Applications that output user/group names, but their output is never parsed by other applications.
PAGE 6
Developers should read this section in its entirety, along with the related appendices, to ensure all issues are understood. Developers should also become familiar with the administrative issues described in this paper. 5.1 Checklist to Find out Whether Your Program is Long User/Group Name Clean and Methods to Make Them Clean Please note, this checklist, assumes that "name" means user name or group name. 1.
PAGE 7
Ø Make sure the file system limits does not create problems with longer user /group name, by either truncating the name if it is OK, or designing a new hashing algorithm to generate a unique file name, instead of using the name itself. 6. Are there places where names are collected into a fixed size buffer? An example would be such as members defined in /etc/group are limited to LINE_MAX bytes long.
PAGE 8
• • System-wide configuration (lugadmin) User level configuration(environment variable) 6.3 Buffer Overflow tests Ensure that there are test cases that validate buffer overflow conditions. This ensures that there are no security vulnerabilities, especially in setuid programs. 7.0 Summary HP has provided expanded user and group names in response to the needs expressed by customers. This feature increases the maximum user and group name lengths from eight and 16 bytes (respectively) to 255.