Problem - Kevin Tafuro

cant window of time between when a CA revokes a certificate and when a new CRL
is published.
SSLis widely deployed and works sufficiently well for many applications; however,
because it is difficult to use properly, it is often deployed insecurely. We discuss certificate
verification in Recipes 10.4 through 10.7.
See Also
• Thinking Putty article on defeating biometric fingerprint scanners: http://www.
puttyworld.com/thinputdeffi.html
• RFC 1510: The Kerberos Network Authentication Service (V5)
• RFC 2617: HTTP Authentication: Basic and Digest Access Authentication
• Recipes 4.10, 8.8, 8.9, 8.10, 8.11, 8.12, 8.13, 18.16, 8.21, 10.1, 10.4, 10.5, 10.6,
10.7
8.2 Getting User and Group Information on Unix
Problem
You need to discover information about a user or group, and you have a username or
user ID or a group name or ID.
Solution
On Unix, user and group names correspond to numeric identifiers. Most system calls
require numeric identifiers upon which to operate, but names are typically easier for
people to remember. Therefore, most user interactions involve the use of names
rather than numbers. The standard C runtime library provides several functions to
map between names and numeric identifiers for both groups and users.
Discussion
Declarations for the functions and data types needed to map between names and
numeric identifiers for users are in the header file pwd.h. Strictly speaking, mapping
functions do not actually exist. Instead, one function provides the ability to look up
user information using the user’s numeric identifier, and another function provides
the ability to look up user information using the user’s name.
The function used to look up user information by numeric identifier has the following
signature:
#include
#include
struct passwd *getpwuid(uid_t uid);
372 | Chapter 8: Authentication and Key Exchange
This is the Title of the Book, eMatter Edition
Copyright © 2007 O’Reilly & Associates, Inc. All rights reserved.