PRCHES11 ;WISC/RHD/AKS-ESIG MAINTENANCE ROUTINE ; 1/4/93 11:04 AM
V ;;5.1;IFCAP;;Oct 20, 2000
;Per VHA Directive 10-93-142, this routine should not be modified.
;ROUTINE FOR MAINTAINING FIELD 3 (ELECTRONIC SIGNATURE), FILE 443
DECODE(LEVEL0) ;Extrinsic Function to return hashed esig to readable form.
;returns "" if unsuccessful
NEW RECORD,RECORD1,RECORD12,VERSION,PERSON,SIG,CHECKSUM
S RECORD=$G(^PRC(443,LEVEL0,0)) I RECORD="" Q ""
S VERSION=$P(RECORD,"^",14)
S PERSON=+$P(RECORD,"^",2)
I VERSION'="",VERSION'=1 Q ""
S SIG=$P(RECORD,"^",3)
D1 ;decode e signature for version 1
S CHECKSUM=$$SUM^PRCUESIG(LEVEL0_"^"_$$STRING(RECORD))
Q $$DECODE^PRCUESIG(SIG,PERSON,CHECKSUM)
ENCODE(LEVEL0,USERNUM,Y) ;Encode esig for version 1 only
NEW RECORD,SIGBLOCK,CHECKSUM,OLDUSER
S USERNUM=+USERNUM
I USERNUM=0 S Y=-3 Q ;-3 no user number
S SIGBLOCK=$P($G(^VA(200,USERNUM,20)),"^",2)
I SIGBLOCK="" S Y=-2 Q ;-2 no signature block
S RECORD=$G(^PRC(443,LEVEL0,0))
I RECORD="" S Y=-1 Q ;-1 no record
I $P(RECORD,"^",3)'="" S Y=-4 Q ;-4 cannot re-sign record
S OLDUSER=+$P(RECORD,"^",2)
I OLDUSER=0 S $P(RECORD,"^",2)=USERNUM
I OLDUSER>0 S USERNUM=OLDUSER
S:$P(RECORD,"^",4)="" $P(RECORD,"^",4)=$$NOW^PRCUESIG
S CHECKSUM=$$SUM^PRCUESIG(LEVEL0_"^"_$$STRING(RECORD))
S $P(RECORD,"^",3)=$$ENCODE^PRCUESIG(SIGBLOCK,USERNUM,CHECKSUM)
S $P(RECORD,"^",14)=1,$P(RECORD,"^",13)=$$SUM^PRCUESIG(SIGBLOCK)
S ^PRC(443,LEVEL0,0)=RECORD
S Y=1 Q
REMOVE(LEVEL0) ;Entry point to remove esig
NEW I,RECORD
S RECORD=$G(^PRC(443,LEVEL0,0))
F I=2,3,4,13 S $P(RECORD,"^",I)=""
S ^PRC(443,LEVEL0,0)=RECORD
Q
VERIFY(LEVEL0) ;extrinsic function to verify version 1 signature. Returns 1 if valid, 0 if not valid
NEW RECORD,VERSION,SIGBLOCK
S RECORD=$G(^PRC(443,LEVEL0,0))
S VERSION=$P(RECORD,"^",14),SIGBLOCK=$P(RECORD,"^",13)
I VERSION_SIGBLOCK="" Q 1
Q ($$SUM^PRCUESIG($$DECODE(LEVEL0))=SIGBLOCK)
STRING(X) ;Build String of critical fields
Q $P(X,"^")_"^"_$P(X,"^",4)_"^"_$P(X,"^",9)
--- Routine Detail --- with STRUCTURED ROUTINE LISTING ---[H[J[2J[HPRCHES11 2050 printed Dec 13, 2024@02:07:17 Page 2
PRCHES11 ;WISC/RHD/AKS-ESIG MAINTENANCE ROUTINE ; 1/4/93 11:04 AM
V ;;5.1;IFCAP;;Oct 20, 2000
+1 ;Per VHA Directive 10-93-142, this routine should not be modified.
+2 ;ROUTINE FOR MAINTAINING FIELD 3 (ELECTRONIC SIGNATURE), FILE 443
DECODE(LEVEL0) ;Extrinsic Function to return hashed esig to readable form.
+1 ;returns "" if unsuccessful
+2 NEW RECORD,RECORD1,RECORD12,VERSION,PERSON,SIG,CHECKSUM
+3 SET RECORD=$GET(^PRC(443,LEVEL0,0))
IF RECORD=""
QUIT ""
+4 SET VERSION=$PIECE(RECORD,"^",14)
+5 SET PERSON=+$PIECE(RECORD,"^",2)
+6 IF VERSION'=""
IF VERSION'=1
QUIT ""
+7 SET SIG=$PIECE(RECORD,"^",3)
D1 ;decode e signature for version 1
+1 SET CHECKSUM=$$SUM^PRCUESIG(LEVEL0_"^"_$$STRING(RECORD))
+2 QUIT $$DECODE^PRCUESIG(SIG,PERSON,CHECKSUM)
ENCODE(LEVEL0,USERNUM,Y) ;Encode esig for version 1 only
+1 NEW RECORD,SIGBLOCK,CHECKSUM,OLDUSER
+2 SET USERNUM=+USERNUM
+3 ;-3 no user number
IF USERNUM=0
SET Y=-3
QUIT
+4 SET SIGBLOCK=$PIECE($GET(^VA(200,USERNUM,20)),"^",2)
+5 ;-2 no signature block
IF SIGBLOCK=""
SET Y=-2
QUIT
+6 SET RECORD=$GET(^PRC(443,LEVEL0,0))
+7 ;-1 no record
IF RECORD=""
SET Y=-1
QUIT
+8 ;-4 cannot re-sign record
IF $PIECE(RECORD,"^",3)'=""
SET Y=-4
QUIT
+9 SET OLDUSER=+$PIECE(RECORD,"^",2)
+10 IF OLDUSER=0
SET $PIECE(RECORD,"^",2)=USERNUM
+11 IF OLDUSER>0
SET USERNUM=OLDUSER
+12 if $PIECE(RECORD,"^",4)=""
SET $PIECE(RECORD,"^",4)=$$NOW^PRCUESIG
+13 SET CHECKSUM=$$SUM^PRCUESIG(LEVEL0_"^"_$$STRING(RECORD))
+14 SET $PIECE(RECORD,"^",3)=$$ENCODE^PRCUESIG(SIGBLOCK,USERNUM,CHECKSUM)
+15 SET $PIECE(RECORD,"^",14)=1
SET $PIECE(RECORD,"^",13)=$$SUM^PRCUESIG(SIGBLOCK)
+16 SET ^PRC(443,LEVEL0,0)=RECORD
+17 SET Y=1
QUIT
REMOVE(LEVEL0) ;Entry point to remove esig
+1 NEW I,RECORD
+2 SET RECORD=$GET(^PRC(443,LEVEL0,0))
+3 FOR I=2,3,4,13
SET $PIECE(RECORD,"^",I)=""
+4 SET ^PRC(443,LEVEL0,0)=RECORD
+5 QUIT
VERIFY(LEVEL0) ;extrinsic function to verify version 1 signature. Returns 1 if valid, 0 if not valid
+1 NEW RECORD,VERSION,SIGBLOCK
+2 SET RECORD=$GET(^PRC(443,LEVEL0,0))
+3 SET VERSION=$PIECE(RECORD,"^",14)
SET SIGBLOCK=$PIECE(RECORD,"^",13)
+4 IF VERSION_SIGBLOCK=""
QUIT 1
+5 QUIT ($$SUM^PRCUESIG($$DECODE(LEVEL0))=SIGBLOCK)
STRING(X) ;Build String of critical fields
+1 QUIT $PIECE(X,"^")_"^"_$PIECE(X,"^",4)_"^"_$PIECE(X,"^",9)
