A2osX/LIB/LIBTCPIP.S.DNS.txt

PR#3
PREFIX /A2OSX.SRC
NEW
INC 1
AUTO 6
				.LIST OFF	
				.OP	65C02
*--------------------------------------
DNS.CLEAR		ldx #K.DNSCACHE.SIZE*S.DNSCACHE
.1				stz DNS.CACHE-1,x
				dex
				bne .1
				clc
				rts
*--------------------------------------
* DNS.QUERY
*  In:
*	PULLA = hostname PSTR 
*   PULLW = PTR to IP to fill with cached data
*  Out:
*   CC: hit: IP filled with address
*   CS: missed 
*--------------------------------------
DNS.QUERY		>PULLB hHOST			Get host string hMem
				>SYSCALL SYS.GetMemPtrA
				>STYA ZPDNSHostname
				>PULLW ZPDNSIP			Get IP address to fill
				
				ldx #0
				
.1				lda DNS.CACHE,x
				beq .6					empty DNS cache entry?
				
				lda DNS.CACHE+S.DNSCACHE.hNAME,x
				>SYSCALL SYS.GetMemPtrA
				>STYA ZPQuickPtr3
				lda (ZPDNSHostname)
				cmp (ZPQuickPtr3)		Same Length?
				bne .6
				tay
.2				lda (ZPDNSHostname),y
				jsr ToLowerCaseA
				cmp (ZPQuickPtr3),y
				bne .6
				dey
				bne .2
				
				lda DNS.CACHE,x			get back status...
				bpl .4					Pending...
				
				ldy #0
.3				lda DNS.CACHE+S.DNSCACHE.IP,x
				sta (ZPDNSIP),y
				inx
				iny
				cpy #4
				bne .3
				clc
				rts

.4				sec
				rts
				
.6				txa
				clc
				adc #S.DNSCACHE
				tax
				cmp #K.DNSCACHE.SIZE*S.DNSCACHE
				bne .1
				
DNS.REQUEST		jsr NEW.UDP.FRAME
				bcc .1
				
				bra *
				
				rts
				
.1				phx
				
				ldy #S.UDP.SRCPORT
				lda /UDP.PORT.DNS
				sta (ZPFrameBase1),y
				iny
				lda #UDP.PORT.DNS
				sta (ZPFrameBase1),y
				
				ldy #S.UDP.DSTPORT
				lda /UDP.PORT.DNS
				sta (ZPFrameBase1),y
				iny
				lda #UDP.PORT.DNS
				sta (ZPFrameBase1),y
				
				ldy #S.DNS.F
				lda /S.DNS.F.RD
				sta (ZPFrameBase1),y
				iny 
				lda #S.DNS.F.RD
				sta (ZPFrameBase1),y
				
				ldy #S.DNS.QDCOUNT
				lda /1
				sta (ZPFrameBase1),y
				iny
				lda #1
				sta (ZPFrameBase1),y
				
				lda #S.DNS
				clc
				adc ZPFrameBase1
				sta ZPFramePtr1
				lda /S.DNS
				adc ZPFrameBase1+1
				sta ZPFramePtr1+1
				
				lda (ZPDNSHostname)		Get hostname len
				tay
				ldx #0
.2				lda (ZPDNSHostname),y
				cmp #'.'
				bne .3
				txa
				ldx #$FF
.3				sta (ZPFramePtr1),y
				inx
				dey
				bne .2
				txa
				sta (ZPFramePtr1)
				
				lda (ZPDNSHostname)
				tay
				iny
				lda #$0					Ending #0
				sta (ZPFramePtr1),y
				
				iny
				lda /S.DNS.QTYPE.A
				sta (ZPFramePtr1),y
				iny
				lda #S.DNS.QTYPE.A
				sta (ZPFramePtr1),y
				
				iny
				lda /S.DNS.QCLASS.IN
				sta (ZPFramePtr1),y
				iny
				lda #S.DNS.QCLASS.IN
				sta (ZPFramePtr1),y

				lda (ZPDNSHostname)		Get hostname len again (QNAME)
				clc						
				adc #6					(len+1) + Ending 0 + QTYPE + QCLASS
				adc #S.DNS
				sta ZPFrameLen1
				lda #0
				adc /S.DNS
				sta ZPFrameLen1+1
				
				ldx #S.IPCFG.DNS
				ldy #S.IP.DST
				
				lda IPCFG,x
				beq .5
				
.4				lda IPCFG,x
				sta (ZPFrameBase1),y
				iny
				inx
				cpx #S.IPCFG.DNS+4
				bne .4
				jsr SEND.UDP.FRAME.I
				bcs .8
				
.5				ldx #S.IPCFG.DNS+4
				ldy #S.IP.DST
				
				lda IPCFG,x
				beq .7
				
.6				lda IPCFG,x
				sta (ZPFrameBase1),y
				iny
				inx
				cpx #S.IPCFG.DNS+8
				bne .6
				jsr SEND.UDP.FRAME.I
				bcs .8
				
.7				jsr DNS.ADD.PENDING.I
				
.8				pla
				>SYSCALL SYS.FreeMemA
				sec
				rts
*--------------------------------------
* DNS.ADD
*  In:
*	PULLA = hostname PSTR to Add
*   PULLW = PTR to IP
*	PULLW = TTL
*--------------------------------------
DNS.ADD			>PULLB hHOST			Get host string hMem
				>SYSCALL SYS.GetMemPtrA
				>STYA ZPDNSHostname
				>PULLW ZPDNSIP			Get host IP address
				>PULLW HOST.TTL
				lda #S.DNSCACHE.STATUS.RESOLVED
				bra DNS.ADD.I

DNS.ADD.PENDING.I
				lda #S.DNSCACHE.STATUS.PENDING
				
DNS.ADD.I		sta Status
				ldx #0
				
.1				lda DNS.CACHE,x
				beq	DNS.ADD.ENTRY		free ?
				
				lda DNS.CACHE+S.DNSCACHE.hNAME,x
				>SYSCALL SYS.GetMemPtrA
				>STYA ZPQuickPtr3
				lda (ZPDNSHostname)
				cmp (ZPQuickPtr3)		Same Length?
				bne .4
				
				tay
.2				lda (ZPDNSHostname),y
				jsr ToLowerCaseA
				cmp (ZPQuickPtr3),y
				bne .4
				dey
				bne .2
				
				bra DNS.UPD.ENTRY
				
.4				txa
				clc
				adc #S.DNSCACHE
				cmp #K.DNSCACHE.SIZE*S.DNSCACHE
				beq .5
				tax
				bra .1

.5				lda DNS.CACHE+S.DNSCACHE.hNAME		discard oldest entry hNAME
				>SYSCALL SYS.FreeMemA
				
				ldx #K.DNSCACHE.SIZE*S.DNSCACHE-S.DNSCACHE
.6				lda DNS.CACHE+S.DNSCACHE-1,x
				sta DNS.CACHE-1,x
				dex
				bne .6

				ldx #K.DNSCACHE.SIZE*S.DNSCACHE-S.DNSCACHE				
				
DNS.ADD.ENTRY	phx
				lda (ZPDNSHostname)
				inc						add 1 for len
				tay
				lda #0
				>PUSHYA					push PSTR len
				>PUSHBI 0				no option
				>SYSCALL SYS.GetMem
				bcc .10
				plx
				rts
				
.10				>STYA ZPQuickPtr3
				txa
				plx
				sta DNS.CACHE+S.DNSCACHE.hNAME,x

				lda (ZPDNSHostname)
				sta (ZPQuickPtr3)
				tay
				
.1				lda (ZPDNSHostname),y
				jsr ToLowerCaseA
				sta (ZPQuickPtr3),y
				dey
				bne .1
	
DNS.UPD.ENTRY	lda Status
				sta DNS.CACHE,x
				bpl .9					pending...
				
				lda HOST.TTL
				sta DNS.CACHE+S.DNSCACHE.TTL,x
				lda HOST.TTL+1
				sta DNS.CACHE+S.DNSCACHE.TTL+1,x
				
				ldy #0
.2				lda (ZPDNSIP),y
				sta DNS.CACHE+S.DNSCACHE.IP,x
				inx
				iny
				cpy #4
				bne .2
				
				clc
				rts
.9				sec
				rts
*--------------------------------------
DNS.GETCACHE	>LDYA L.DNS.CACHE
				clc
				rts
*--------------------------------------
*				PRIVATE
*--------------------------------------
MAN
SAVE LIB/LIBTCPIP.S.DNS
LOAD LIB/LIBTCPIP.S
ASM