FreeBSD Manual Pages
owampd.limits(5) File Formats Manual owampd.limits(5) NAME owampd.limits - One-way latency server policy configuration file DESCRIPTION The owampd.limits file is used to define the policy configuration for the owampd program. It allows the system administrator to allocate the resources in a variety of ways. There are two parts to the policy configuration: Authentication Who is making the request? This can be very specific to an indi- vidual user or it can be more general in that the connection is coming from some particular network. Authorization Now that the connection has been generally identified, what will owampd allow it to do? The authentication is done by assigning a limitclass to each new con- nection as it comes in. Each limitclass has a set of limits associated with it. The limitclasses are hierarchical, so a connection must pass the limit restrictions of the given limitclass as well as all parent classes. Within the owampd.limits file, assign lines are used to assign a limit- class to a given connection. limit lines are used to define a limit- class and set the limits associated with that limitclass. The file is read sequentially, and it is not permitted to use a limitclass before it is defined using a limit line. The format of this file is: • Comment lines are any line where the first non-whitespace character is '#'. These lines are counted to return line numbers in error messages but are otherwise ignored by owampd. • Lines may be continued using the semi-standard '\' char- acter followed immediately by a newline. This is the only valid place for the '\' character. If it is found else- where a syntax error is reported. • Blank lines are treated as comment lines. • All other lines must conform to the syntax of a limit line or an assign line. CONFIGURATION OPTIONS limit This directive is used to define the limitclass hierarchy. It defines the limitclassname as well as the limits associated with that class. A limitclassname may only be defined once. The for- mat of the limit directive is: limit limitclassname with limtype=value[,limtype=value]* limitclassname defines the name of the class with the given lim- its. Whitespace is used as a separator but is otherwise ignored. limitclassname may be used as a directory name component within owampd, so take care not to use characters that would be in- valid. (i.e. '*' or '/' would be particularly bad.) limtype and value indicate the particular type of limit and value to apply to this limitclass. The available settings for limtype are: limtype valid values default ----------------------------------------------------------------- allow_open_mode on/off on bandwidth integer (bits/sec) 0 (unlimited) disk integer (bytes) 0 (unlimited) delete_on_fetch on/off off parent already defined limitclassname null allow_open_mode This limit is only useful if the class is assigned to a netmask. It is used to limit specific IP/netmask identi- ties to only encrypted or authenticated mode transactions or to allow open mode. bandwidth Maximum amount of bandwidth to allow limitclass to use concurrently in all one-way tests. 0 indicates unlimited by policy, but remember this is checked all the way to the root of the hierarchy. (If you want an unlimited lim- itclass, your root must be unlimited as well as the whole path down to the given limitclass.) disk Maximum amount of disk space to allow a given limitclass to consume. This defines a limit that is used during the authorization of a given test request (this is a soft limit). If the estimated file size for a test request is larger than the disk limit, the test request will be de- nied. Additionally, because a given test can actually consume more space than this estimate due to duplicate packets, the diskfudge factor is used upon the completion of a test to decide if the file should be kept. If the new file causes the disk space used by a limitclass to be larger than the disk limit multiplied by the diskfudge factor (this defines the hard limit) the file will be deleted. delete_on_fetch Indicates that buffered data files should be automati- cally be deleted by the owampd server as soon as they are fetched. parent The first limit line cannot have a parent since none have been defined yet. As such, the first line defines the root of your class hierarchy. All remaining limit lines MUST assign a parent. (It is hierarchical, after all.) assign The assign directive is used to assign a limitclass to a given connection. Basically, it authenticates the connection. The format of the assign directive is: assign authtype [args] limitclassname authtype identifies the type of authentication being used. Whitespace is used as a separator but is otherwise ignored. lim- itclassname must have been previously defined with the limit di- rective earlier in the file. The available settings for authtype are: default Used if no other assignment matches. It takes no args. net subnet Assign a specific subnet to a given limitclass. subnet must be specified using VLSM notation (IP/nbits). The only arg is the subnet. For example: 127.0.0.1/32 would match only the loopback IPv4 address. ::1/128 would match only the loopback IPv6 address. 192.168.1.0/24 would match all hosts on the 192.168.1.XXX net- work. There must be no set bits in the non-masked portion of the address part of the subnet specification. i.e., 192.168.1.1/24 would be an invalid subnet due to the bit set in the fourth octet. user user Assign a specific user to a given limitclass. The user must be defined in the owampd.pfs file. AUTHENTICATION PROCESS owampd determines if it should allow a connection from the client based upon the authentication mode of the request and the source IP address of the connection. If the client connection is in authenticated or en- crypted mode, the daemon does not do any filtering based upon the source address of the connection. (See the -A option to owping and the authmode option in owampd.conf.) In these modes owampd simply uses the identity of the connection to determine the limitclass limits. If the connection is made in open mode, then owampd first uses the source ad- dress to determine if owampd should allow an open mode connection from that subnet at all. (This is the purpose of the allow_open_mode limtype described above.) If open mode is allowed from this subnet, then the limitclass is determined by the closest subnet match defined by the as- sign net lines in the owampd.limits file. EXAMPLES An initial limit line might look like: limit root with \ bandwidth=900m, \ disk=2g, \ allow_open_mode=off This would create a limitclass named root. Because no parent is speci- fied, this must be the first limitclass defined in the file. This lim- itclass has very liberal limits (900m limit on bandwidth, and 2 GB of disk space). However, open mode authentication is not enabled for this limitclass, so the connections that get these limits must successfully authenticate using an AES key derived from the pass-phrase in the owampd.pfs file. If an administrator also wants to create a limitclass that is used to deny all requests, they might add: limit jail with \ parent=root, \ bandwidth=1, \ disk=1, \ allow_open_mode=off This would create a limitclass named jail. Because the limits for band- width and disk are so low, virtually all tests will be denied. al- low_open_mode is off, so initial connections that are not in authenti- cated or encrypted mode will be dropped immediately. (It would not make much sense to assign a user identity to this limitclass. If you don't want connections from a particular user identity the best thing to do is to remove that user from the owampd.pfs file.) If the administrator wanted to allow a limited amount of open tests, they could define a limitclass like: limit open with \ parent=root, \ bandwidth=10k, \ disk=10m, \ allow_open_mode=on This could be used to allow testing by random connections. It limits those tests to 10 kilobits of bandwidth and 10 Mbytes of buffer space. Now, these three limitclasses might be assigned to specific connections in the following ways: # default open assign default open # badguys subnet assign net 192.168.1.0/24 jail # network admins assign user joe root assign user jim root assign user bob root This set of assign lines specifically denies access from any open mode connection from the badguys subnet. It specifically allows access to authenticated or encrypted mode transactions that can authenticate as the identities joe jim or bob (even from the badguys subnet). All other connections would match the assign default rule and get the limits as- sociated with the open limitclass. SEE ALSO owping(1), owampd(8), owampd.limits(5), owampd.pfs(5), aespasswd(1), and the http://e2epi.internet2.edu/owamp/ web site. ACKNOWLEDGMENTS This material is based in part on work supported by the National Sci- ence Foundation (NSF) under Grant No. ANI-0314723. Any opinions, find- ings and conclusions or recommendations expressed in this material are those of the author(s) and do not necessarily reflect the views of the NSF. $Date: 2006-11-07 00:54:55 -0500 (Tue, 07 Nov 200owampd.limits(5)
NAME | DESCRIPTION | CONFIGURATION OPTIONS | AUTHENTICATION PROCESS | EXAMPLES | SEE ALSO | ACKNOWLEDGMENTS
Want to link to this manual page? Use this URL:
<https://man.freebsd.org/cgi/man.cgi?query=owampd.limits&sektion=5&manpath=FreeBSD+Ports+15.0>