Updated: 11 December 1998

OpenVMS System Services Reference Manual

On Alpha systems, unwinds the call stack.

Format

SYS$GOTO_UNWIND target_invo ,target_pc ,[new_r0] ,[new_r1]

C Prototype

int sys$goto_unwind (void *target_invo, void *(*(target_pc)), unsigned __int64 *new_r0, unsigned __int64 *new_r1);

Arguments

target_invo

OpenVMS usage:	invo_handle
type:	longword (unsigned)
access:	read only
mechanism:	by reference

The address of a location that contains a handle for the target invocation.

If you do not specify the target_invo argument, or if the handle value is 0, an exit unwind is initiated.

target_pc

OpenVMS usage:	address
type:	longword (unsigned)
access:	read only
mechanism:	by reference

The address of a location that contains the address at which execution should continue in the target invocation.

If the target_pc argument is omitted or the value is 0, a system-defined target PC is assumed and execution resumes at the location specified at the return address for the call frame of the target procedure invocation.

new_r0

OpenVMS usage:	quadword_unsigned
type:	quadword (unsigned)
access:	read only
mechanism:	by reference

The address of a location that contains the value to place in the saved R0 location of the mechanism argument vector. The contents of this location are then loaded into the processor R0 register at the time that execution continues in the target invocation.

If the new_r0 argument is omitted, the contents of the processor R0 register at the time of the call to $GOTO_UNWIND are used.

new_r1

OpenVMS usage:	quadword_unsigned
type:	quadword (unsigned)
access:	read only
mechanism:	by reference

Address of a location that contains the value to place in the saved R1 location of the mechanism argument vector. The contents of the location are then loaded into the processor R1 register at the time that execution continues in the target invocation.

If the new_r1 argument is omitted, the contents of the processor R1 register at the time of the call to $GOTO_UNWIND are used.

Description

The Unwind Call Stack service provides the function for a procedure to unwind the call stack.

Required Access or Privileges

None

Required Quota

None

Related Services

$UNWIND

Condition Values Returned

SS$_NORMAL	The service completed successfully.
SS$_ACCVIO	The specified target_invo, target_pc, new_r0, or new_r1 argument is not accessible.

Adds the specified identifier record to the rights list of the process or the system.

Format

SYS$GRANTID [pidadr] ,[prcnam] ,[id] ,[name] ,[prvatr]

C Prototype

int sys$grantid (unsigned int *pidadr, void *prcnam, struct _generic_64 *id, void *name, unsigned int *prvatr, unsigned int segment);

Arguments

pidadr

OpenVMS usage:	process_id
type:	longword (unsigned)
access:	modify
mechanism:	by reference

Process identification (PID) number of the process affected when $GRANTID completes execution. The pidadr argument is the address of a longword containing the PID of the process to be affected. You use --1 to indicate the system rights list. When pidadr is passed, it is also returned; therefore, you must pass it as a variable rather than a constant. If you specify neither pidadr nor prcnam, your own process is used.

prcnam

OpenVMS usage:	process_name
type:	character-coded text string
access:	read only
mechanism:	by descriptor--fixed-length string descriptor

Process name on which $GRANTID operates. The prcnam argument is the address of a character string descriptor containing the process name. The maximum length of the name is 15 characters. Because the UIC group number is interpreted as part of the process name, you must use pidadr to specify the rights list of a process in a different group. If you specify neither pidadr nor prcnam, your own process is used.

id

OpenVMS usage:	rights_holder
type:	quadword (unsigned)
access:	modify
mechanism:	by reference

Identifier and attributes to be granted when $GRANTID completes execution. The id argument is the address of a quadword containing the binary identifier code to be granted in the first longword and the attributes in the second longword.

Use the id argument to modify the attributes of the identifier.

Symbol values are offsets to the bits within the longword. You can also obtain the values as masks with the appropriate bit set using the prefix KGB$M rather than KGB$V. The following symbols for each bit position are defined in the macro library ($KGBDEF).

Bit Position	Meaning When Set
KGB$V_DYNAMIC	Allows holders of the identifier to remove it from or add it to the process rights database using the DCL command SET RIGHTS_LIST.
KGB$V_NOACCESS	Makes any access rights of the identifier null and void. This attribute is intended as a modifier for a resource identifier or the Subsystem attribute.
KGB$V_RESOURCE	Allows holders of an identifier to charge disk space to the identifier. It is used only for file objects.
KGB$V_SUBSYSTEM	Allows holders of the identifier to create and maintain protected subsystems by assigning the Subsystem ACE to the application images in the subsystem.

You must specify either id or name. Because the id argument is returned as well as passed if you specify name, you must pass it as a variable rather than a constant in this case.

name

OpenVMS usage:	char_string
type:	character-coded text string
access:	read only
mechanism:	by descriptor--fixed-length string descriptor

Name of the identifier granted when $GRANTID completes execution. The name argument is the address of a descriptor pointing to the name of the identifier. The identifier is granted as it is created. You must specify either id or name.

prvatr

OpenVMS usage:	mask_longword
type:	longword (unsigned)
access:	write only
mechanism:	by reference

Previous attributes of the identifier. The prvatr argument is the address of a longword used to store the attributes of the identifier if it was previously present in the rights list. If you added rather than modified the identifier, prvatr is ignored.

Description

The Grant Identifier to Process service adds the specified identifier to the rights list of the process or the system. If the identifier is already in the rights list, its attributes are modified to those specified. This service is meant to be used by a privileged subsystem to alter the access rights profile of a user, based on installation policy. It is not meant to be used by the general system user.

The result of passing the pidadr or the prcnam argument, or both, to SYS$GRANTID is summarized in the following table.

prcnam	pidadr	Result
Omitted	Omitted	Current process ID is used; process ID is not returned.
Omitted	0	Current process ID is used; process ID is returned.
Omitted	Specified	Specified process ID is used.
Specified	Omitted	Specified process name is used; process ID is not returned.
Specified	0	Specified process name is used; process ID is returned.
Specified	Specified	Specified process ID is used and process name is ignored.

The result of passing the name or the id argument, or both, to SYS$GRANTID is summarized in the following table.

name	id	Result
Omitted	Omitted	Illegal. The INSFARG condition value is returned.
Omitted	Specified	Specified identifier value is used.
Specified	Omitted	Specified identifier name is used; identifier value is not returned.
Specified	0	Specified identifier name is used; identifier value is returned.
Specified	Specified	Specified identifier value is used and identifier name is ignored.

Note that a value of 0 in either of the preceding tables indicates that the contents of the address specified by the argument is the value 0. The word omitted indicates that the argument was not supplied.

Required Access or Privileges

You need CMKRNL privilege to invoke this service. In addition, you need GROUP privilege to modify the rights list of a process in the same group as the calling process (unless the process has the same UIC as the calling process). You need WORLD privilege to modify the rights list of a process outside the caller's group. You need SYSNAM privilege to modify the system rights list.

Required Quota

None

Related Services

$ADD_HOLDER, $ADD_IDENT, $ASCTOID, $CHANGE_ACL, $CHECK_ACCESS, $CHKPRO, $CREATE_RDB, $ERAPAT, $FIND_HELD, $FIND_HOLDER, $FINISH_RDB, $FORMAT_ACL, $FORMAT_AUDIT, $HASH_PASSWORD, $IDTOASC, $MOD_HOLDER, $MOD_IDENT, $MTACCESS, $PARSE_ACL, $REM_HOLDER, $REM_IDENT, $REVOKID

Condition Values Returned

SS$_WASCLR	The service completed successfully; the rights list did not contain the specified identifier.
SS$_WASSET	The service completed successfully; the rights list already held the specified identifier.
SS$_ACCVIO	The pidadr argument cannot be read or written; prcnam cannot be read; id cannot be read or written; the name cannot be read; or prvatr cannot be written.
SS$_INSFARG	You did not specify either the id or the name argument.
SS$_INSFMEM	The process dynamic memory is insufficient for opening the rights database.
SS$_IVIDENT	The specified identifier name is invalid; the identifier name is longer than 31 characters, contains an illegal character, or does not contain at least one nonnumeric character.
SS$_IVLOGNAM	You specified an invalid process name.
SS$_NONEXPR	You specified a nonexistent process.
SS$_NOPRIV	The caller does not have CMKRNL privilege or is not running in executive or kernel mode, or the caller lacks GROUP, WORLD, or SYSNAM privilege as required.
SS$_NOSUCHID	The specified identifier name does not exist in the rights database. Note that the binary identifier, if given, is not validated against the rights database.
SS$_NOSYSNAM	The operation requires SYSNAM privilege.
SS$_RIGHTSFULL	The rights list of the process or system is full.
RMS$_PRV	The user does not have read access to the rights database.

Because the rights database is an indexed file accessed with OpenVMS RMS, this service can also return RMS status codes associated with operations on indexed files. For descriptions of these status codes, refer to the OpenVMS Record Management Services Reference Manual.

Applies the hash algorithm you select to an ASCII password string and returns a quadword hash value that represents the encrypted password.

Format

SYS$HASH_PASSWORD pwd ,alg ,[salt] ,usrnam ,hash

C Prototype

int sys$hash_password (void *pwd, unsigned char alg, unsigned short int salt, void *usrnam, struct _generic_64 *hash);

Arguments

pwd

OpenVMS usage:	char_string
type:	character-coded text string
access:	read only
mechanism:	by descriptor--fixed-length string descriptor

ASCII password string to be encrypted. The pwd argument is the address of a character string descriptor pointing to the ASCII password. The password string can contain between 1 and 32 characters and use the uppercase characters A through Z, the numbers 0 through 9, the dollar sign ($), and the underscore (_).

The caller must validate the password string before calling $HASH_PASSWORD to ensure that only permitted characters are included.

alg

OpenVMS usage:	byte_unsigned
type:	byte (unsigned)
access:	read only
mechanism:	by value

Algorithm used to hash the ASCII password string. The alg argument is an unsigned byte specifying the hash algorithm. The operating system recognizes the following algorithms.

Symbolic Name	Description
UAI$K_AD_II	Uses a CRC algorithm and returns a longword hash value. This algorithm was used in releases prior to VAX VMS Version 2.0.
UAI$C_PURDY	Uses a Purdy algorithm over salted input. It expects a blank-padded user name and returns a quadword hash value. This algorithm was used during VAX VMS Version 2.0 field test.
UAI$C_PURDY_V	Uses the Purdy algorithm over salted input. It expects a variable-length user name and returns a quadword hash value. This algorithm was used in releases prior to VMS Version 5.4.
UAI$K_PURDY_S	Uses the Purdy algorithm over salted input. It expects a variable-length user name and returns a quadword hash value. This algorithm is used to hash all new passwords in VMS Version 5.4 and later.
UAI$C_PREFERED_ALGORITHM 1	Represents the latest encryption algorithm that the operating system uses to encrypt new passwords. Currently, it equates to UAI$C_PURDY_S. Compaq recommends that you use this symbol in source modules because it always equates with the most recent algorithm.

Values ranging from 128 to 255 are reserved for customer use; the constant UAI$K_CUST_ALGORITHM defines the start of this range.

You can use the UAI$_ENCRYPT and UAI$_ENCRYPT2 item codes with the $GETUAI system service to retrieve the primary and secondary password hash algorithms for a user.

salt

usrnam

hash

Description

The Hash Password service applies the hash algorithm you select to an ASCII password string and returns a quadword hash value that represents the encrypted password.

Other OpenVMS password services allow spaces, tabs, and other blank characters from the user, but they remove those spaces before passing the string to $HASH_PASSWORD. Before calling $HASH_PASSWORD, all white space must be removed from the password string to ensure proper comparison with passwords created by other services.

Required Access or Privileges

None

Required Quota

None

Related Services

$GETUAI, $SETUAI.

Use $GETUAI to get the values for the salt and alg arguments. Use $SETUAI to store the resulting hash using the item codes UAI$_PWD and UAI$_PWD2.

For more information, see the appendix on implementing site-specific security policies in the OpenVMS Programming Concepts Manual.

Condition Values Returned

SS$_NORMAL	The service completed successfully.
SS$_ACCVIO	The input or output buffer descriptors cannot be read or written to by the caller.
SS$_BADPARAM	The specified hash algorithm is unknown or invalid.

Copyright © Compaq Computer Corporation 1998. All rights reserved. Legal

4527PRO_056.HTML