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diff --git a/static/v10/man5/privs.5 b/static/v10/man5/privs.5 new file mode 100644 index 00000000..1a93b792 --- /dev/null +++ b/static/v10/man5/privs.5 @@ -0,0 +1,282 @@ +.TH PRIVS 5 +.SH NAME +privs \- privilege file +.SH DESCRIPTION +The file +.F /etc/privs +expresses the rules whereby +.IR priv (1) +grants privilege. +It consists of a list of statements, +each terminated by a semicolon. +One or more comments, each extending from +.L # +to newline, may precede each statement. +.SS Rights +Rights are defined thus: +.IP +.BI DEFINE " rights-list" ; +.LP +Each right in the comma-separated rights-list +has a name, and optionally a parenthesized parameter type. +The types are +.TP +.B LAB +Label, ordered by lattice value. +.TP +.B RE +Regular expression ordered by language inclusion. +Regular expressions are in the form of +.IR regexp (3), +with enclosing +.L ^( +and +.L )$ +understood. +.TP +.B PRIV +Set of privileges in +.I atopriv +form, ordered by inclusion; see +.IR labtoa (3). +.LP +Examples: +.IP +.L +DEFINE ceiling(LAB), filename(RE), privinstall; +.PP +Rights are identifiers +used solely by +.IR priv ; +they have no other manifestation in the system. +In the example, the +.L ceiling +right involves label comparisons, but has no necessary +connection to process ceilings. +The name could be changed globally to, say, +.L floor +without affecting the interpretation of +.FR /etc/privs . +.SS Authorization +Authorization is expressed by a tree. +Nodes of the authorization tree are named, like +files in the file system, by full pathnames starting +from the root, +.LR / . +Associated with each node are statements to grant rights, +and statements to admit access to the node. +Rights are monotone in the tree: +the rights at a node must be a subset of the rights at its +parent. +Access to a node implies access to its children. +.PP +Right-granting statements have the form +.IP +.BI RIGHTS " nodename rights-list" ; +.LP +A +.I rights-list +is as in a rights +definition, but with explicit values for parameters. +White space or one of the metacharacters +.L ;,() +may be included in a value by placing double +quotes around it. +Examples: +.IP +.EX +.ta \w'RIGHTS 'u +\w'/admin/operations 'u +RIGHTS /admin priv(upxnl), ceiling(ffff...); +RIGHTS /admin/security priv(p), ceiling("ffff ..."); +RIGHTS /admin/operations priv(xn) +.EE +.DT +.PP +Access statements have the form +.IP +.BI ACCESS " nodename pred-list" ; +.LP +Access to the named node is granted when the comma-separated +.I pred-list +is nonempty and all the predicates in the list are satisfied. +A node may have more than one +.B ACCESS +statement. +Legal predicates are +.TP +.BI ID( lognames ) +A regular expression for login names +that have access to this node. +.TP +.BI PW( name\ ... ) +The password associated with one of the +.I names +in +.IR pwfile (5) +must be presented. +.TP +.BI SRC( source ) +A regular expression for the stream identifier of +the standard input. +.SS Rules +Rules give patterns for +requests and show the prerequisite rights for +and the actions to carry out each request: +.IP +.BI REQUEST( arguments ") NEEDS" " rights " DOES " actions \fB;" +.LP +The request part shows +.I arguments +supplied to +.IR priv (1); +normally the arguments spell out the prefix of a +.SM UNIX +command. +The +.B NEEDS +part tells what rights are needed to perform the request. +The rights are as in a rights statement, with substituted parameters; +see `Parameter values'. +.PP +If the process has access to a node that grants +the needed rights (with the parameter in each grant dominating +the parameter of the corresponding need), then the +.I actions +for the request are performed. +Otherwise the request is denied. +Legal actions are +.TP +.B PRIV(gunxlp) +Set one or more process licenses, abbreviated as in +.IR labtoa (3). +.TP +.BI EXEC( args ) +Execute a program given by the +.I args. +Members of the +.I args +list are separated by white space and may specify +substitutions; see `Parameter values'. +.B EXEC +does not do a +.IR sh (1)-like +.B $PATH +search. +.TP +.BI DAEMON( args ) +Same as +.BR EXEC , +but do not wait for the command to complete. +.TP +.BI CEILING( label ) +Set the process ceiling. +.TP +.BI PRIVEDIT( "node file" ) +Read editing commands from the named +.IR file . +Only the subtree at +.I node +is editable; nodes closer to the root cannot be touched. +.TP +.B ANYSRC +Skip the normal check for a trusted source; see +.IR priv (1). +.PP +The order in which nodes of the authorization tree are +visited in evaluating a +.B NEEDS +clause is undefined, however at each node the predicates of the +request are evaluated in order. +The actions of a granted request are also performed in order, +with effects such as privilege settings persisting +until the end of the +.I priv +command or until overridden by a later action. +.SS Parameter values +Parameter values appear in members of +.B NEEDS +and +.B DOES +lists. +A value may be surrounded by double quotes, in which case the +value may contain white space or one of the metacharacters +.LR ,;() . +A value may contain substitution marks, +.BR $0 , +.BR $1 , +\&... +Each such mark is replaced from the +.I priv +invocation, +.B $0 +standing for the match to the first +.I argument +of the +.B REQUEST +and so on. +If a star is appended to the mark (e.g. +.BR $0* , +.BR $1* ), +the argument and all following ones are copied +into the parameter list. +Nothing can follow a star mark in a parameter. +.SS Editing +Statements of the above forms may be used with action +.B PRIVEDIT +to augment a +.I privs +file. +Further types of statements exist for editing only: +.TP +.BI RMDEFINE " rights-list " ; +Remove all occurrences of the listed rights from the file. +.TP +.BI RMACCESS " nodename pred-list " ; +.PD 0 +.TP +.BI RMRIGHTS " nodename rights-list " ; +Remove the given access list or the given rights +from the named node. +If the list is empty, remove all access lists or rights. +.PD +.TP +.BI RMREQUEST( arguments ) ; +Remove the +.B REQUEST +with identical +.I arguments. +.TP +.BI RMNODE " path-list" ; +Remove the listed subtrees. +.PP +.BR DEFINE , +.BR RMDEFINE , +.BR REQUEST , +and +.BR RMREQUEST +are understood to modify the root. +.SH EXAMPLES +.EX +REQUEST(session -l) + NEEDS ceiling($2) + DOES PRIV(nx) EXEC(/bin/session -l $2); +REQUEST(/etc/downgrade -l) + NEEDS downgrade($2) + DOES PRIV(nx) EXEC($*); +.EE +.SH FILES +.F /etc/privs +.SH SEE ALSO +.IR priv (1), +.IR privserv (8) +.SH BUGS +There is no way to quote a newline or an initial +double quote in parameters. +.br +If an +.B ACCESS +or +.B RMACCESS +statement contains duplicate predicates, +.B RMACCESS +may remove an unintended list. |