Because UNIX supports so many avenues of networking, securing UNIX servers is a formidable task. This is in contrast to servers implemented on the Macintosh or IBMcompatible platforms. The operating systems most common to these platforms do not support anywhere close to the number of network protocols natively available under UNIX.
Traditionally, UNIX security has been a complex field. In this respect, UNIX is often at odds with itself. UNIX was developed as the ultimate open system (that is, its source code has long been freely available, the system supports a wide range of protocols, and its design is uniquely oriented to facilitate multiple forms of communication). These attributes make UNIX the most popular networking platform ever devised. Nevertheless, these same attributes make security a difficult thing to achieve. How can you allow every manner of open access and fluid networking while still providing security? Over the years, many advances have been made in UNIX security. These, in large part, were spawned by governmental use of the operating system. Most versions of UNIX have made it to the Evaluated Products List (EPL). Some of these advances (many of which were implemented early in the operating system's history) include:
• Encrypted passwords
• Strong file and directory-access control
• System-level authentication procedures
• Sophisticated logging facilities
UNIX is used in many environments that demand security. As such, there are hundreds of security programs available to tune up or otherwise improve the security of a UNIX system. Many of these tools are freely available on the Internet. Such tools can be classified into two basic categories:
• Security audit tools
• System logging tools
Security audit tools tend to be programs that automatically detect holes within systems. These typically check for known vulnerabilities and common misconfigurations that can lead to security breaches. Such tools are designed for wide-scale network auditing and, therefore, can be used to check many machines on a given network. These tools are advantageous because they reveal inherent weaknesses within the audited system. However, these tools are also liabilities because they provide powerful capabilities to crackers in the void. In the wrong hands, these tools can be used to compromise many hosts.
Conversely, system logging tools are used to record the activities of users and system messages. These logs are recorded to plain text files or files that automatically organize themselves into one or more database formats. Logging tools are a staple resource in any UNIX security toolbox. Often, the logs generated by such utilities form the basis of evidence when you pursue an intruder or build a case against a cracker. However, deep logging of the system can be costly in terms of disk space. Moreover, many of these tools work flawlessly at collecting data, but provide no easy way to interpret it. Thus, security personnel may be faced with writing their own programs to perform this task.
UNIX security is a far more difficult field than security on other platforms, primarily because UNIX is such a large and complicated operating system. Naturally, this means that obtaining personnel with true UNIX security expertise may be a laborious and costly process. For although these people aren't rare particularly, most of them already occupy key positions in firms throughout the nation. As a result, consulting in this area has become a lucrative business.
One good point about UNIX security is that because UNIX has been around for so long, much is known about its inherent flaws. Although new holes crop up on a fairly regular basis, their sources are quickly identified. Moreover, the UNIX community as a whole is well networked with respect to security. There are many mailing lists, archives, and online databases of information dealing with UNIX security. The same cannot be so easily said for other operating systems. Nevertheless, this trend is changing, particularly with regard to Microsoft Windows NT. There is now strong support for NT security on the Net, and that support is growing each day.
Source: Maximum Security - Protecting Your Internet Site and Network
Traditionally, UNIX security has been a complex field. In this respect, UNIX is often at odds with itself. UNIX was developed as the ultimate open system (that is, its source code has long been freely available, the system supports a wide range of protocols, and its design is uniquely oriented to facilitate multiple forms of communication). These attributes make UNIX the most popular networking platform ever devised. Nevertheless, these same attributes make security a difficult thing to achieve. How can you allow every manner of open access and fluid networking while still providing security? Over the years, many advances have been made in UNIX security. These, in large part, were spawned by governmental use of the operating system. Most versions of UNIX have made it to the Evaluated Products List (EPL). Some of these advances (many of which were implemented early in the operating system's history) include:
• Encrypted passwords
• Strong file and directory-access control
• System-level authentication procedures
• Sophisticated logging facilities
UNIX is used in many environments that demand security. As such, there are hundreds of security programs available to tune up or otherwise improve the security of a UNIX system. Many of these tools are freely available on the Internet. Such tools can be classified into two basic categories:
• Security audit tools
• System logging tools
Security audit tools tend to be programs that automatically detect holes within systems. These typically check for known vulnerabilities and common misconfigurations that can lead to security breaches. Such tools are designed for wide-scale network auditing and, therefore, can be used to check many machines on a given network. These tools are advantageous because they reveal inherent weaknesses within the audited system. However, these tools are also liabilities because they provide powerful capabilities to crackers in the void. In the wrong hands, these tools can be used to compromise many hosts.
Conversely, system logging tools are used to record the activities of users and system messages. These logs are recorded to plain text files or files that automatically organize themselves into one or more database formats. Logging tools are a staple resource in any UNIX security toolbox. Often, the logs generated by such utilities form the basis of evidence when you pursue an intruder or build a case against a cracker. However, deep logging of the system can be costly in terms of disk space. Moreover, many of these tools work flawlessly at collecting data, but provide no easy way to interpret it. Thus, security personnel may be faced with writing their own programs to perform this task.
UNIX security is a far more difficult field than security on other platforms, primarily because UNIX is such a large and complicated operating system. Naturally, this means that obtaining personnel with true UNIX security expertise may be a laborious and costly process. For although these people aren't rare particularly, most of them already occupy key positions in firms throughout the nation. As a result, consulting in this area has become a lucrative business.
One good point about UNIX security is that because UNIX has been around for so long, much is known about its inherent flaws. Although new holes crop up on a fairly regular basis, their sources are quickly identified. Moreover, the UNIX community as a whole is well networked with respect to security. There are many mailing lists, archives, and online databases of information dealing with UNIX security. The same cannot be so easily said for other operating systems. Nevertheless, this trend is changing, particularly with regard to Microsoft Windows NT. There is now strong support for NT security on the Net, and that support is growing each day.
Source: Maximum Security - Protecting Your Internet Site and Network
