srvtab

Table A-1: Continued

 

_____________________________________________________________________

 

⎜

 

⎜

the invoked program (e.g., login) will overwrite this entry in the system utmpx file

⎜

⎜

 

⎜

with valid user information. This style of accounting does not make an entry in the

⎜

⎜

 

⎜

system wtmpx file; it assumes that the invoked program will make the initial entry,

⎜

⎜

 

⎜

thus avoiding multiple entries.

⎜

⎜

R

⎜

Rejects the call unless the resulting mapped user ID has an ordinary shell. An ordinary

⎜

⎜

⎜

⎜

⎜

 

⎜

shell is defined as either a null shell field in the password file (the default /bin/sh), or a

⎜

⎜

 

⎜

shell field that references a program that ends in the string "sh" and the basename of

⎜

⎜

 

⎜

that program does not begin with the letter r (restricted shells like /bin/rsh).

⎜

⎜

T

⎜ Traps the call, rejecting it with a NAK code obtained from the first argument of the

⎜

⎜

 

⎜ program arguments field. The remainder of the program argument field will be pro-

⎜

⎜

 

⎜ cessed for "special code" expansion and will then be logged to the server log file.

⎜

⎜

U

⎜

Creates a USER_PROCESS type utmp entry for the invoked program. This style of

⎜

⎜

 

⎜

accounting makes an entry in the system utmpx file that is displayed when using the

⎜

⎜

 

⎜

default options of the who command. It also makes an entry in the system wtmpx file

⎜

⎜

 

⎜

that may be displayed using the command last.

⎜

⎜

 

⎜

 

⎜

⎜

/

⎜ If a / flag is present, the flags that follow it act as the default flag settings and the user-

⎜

⎜

 

⎜ supplied protocol field portion of the dialstring (if any) replaces the part after the /.

⎜

⎜

 

⎜ This flag is invalid if the user-supplied protocol field contains illegal flags or if it con-

⎜

⎜

 

⎜ tains an I, L, R, T or U flag.

⎜

⎜

 

⎜

The flags for remote execution channels are often specified as /vaex to indicate that the

⎜

⎜

 

⎜

default is to honor arguments, environment variables, and to return an exit code.

⎜

 

 

 

 

 

User Field

The user field (user ID mapping) of a server table entry determines the way in which the calling user ID is treated. The user ID in the call request may be passed to the program unchanged, translated (mapped) into a new user ID, restricted to a range, or ignored altogether by using a fixed user ID. See Table A-2.

Regardless of the user ID mapping mode specified, a valid /etc/passwd entry must exist for the resultant user ID in order for the server table entry to match the call request. A program cannot be invoked with an invalid or illegal user ID.

A Appendix

Issue 3

A-5