Topics

16

General Security Information / LANL attack statistics

« on: August 25, 2005, 11:02:48 pm »

http://www.lamonitor.com/articles/2005/08/25/headline_news/news03.txt

On a $15 million a year budget, Los Alamos National Laboratory is waging a daily battle against a barrage of threats to its computer network.

Alexander D. Kent, deputy group leader for the lab's network engineering group, said 25,000 computers processing about 850 gigabytes of data in 20 million legitimate sessions a day are facing a growing risk.

A graph of Internet sessions between May and mid-August this year shows at least five million "malicious" sessions on slow days and 10-15 million during peaks.

On weekends, when LANL activity slows, 90 percent or more of the computer activity appears to be malicious.

Malicious activity could mean anything from a sophisticated hacker or terrorist or a foreign intelligence operative to unsophisticated pranksters and adolescent mischief.

The lab protects itself with network firewalls for its public network and "air gaps" - compartmentalization - for its classified net.

The numbers they have given a rather impressive. I'd never have thought that they would be getting 5 million on slow days.

17

Operating System Development / [FASM] Generating Fat12 formatted bootsector.

« on: June 19, 2005, 06:40:24 pm »

Code: [Select]

use16
org 0x7C00

BYTES_PER_SECTOR = 512

RESERVED_SECTORS = 1
MEDIA_DESCRIPTOR = 0xF0

NUMBER_OF_HEADS = 0x2
NUMBER_OF_TRACKS = 0x50
SECTORS_PER_TRACK = 0x12

NUMBER_OF_SECTORS = NUMBER_OF_HEADS * NUMBER_OF_TRACKS * SECTORS_PER_TRACK
SECTORS_PER_CLUSTER = 1
NUMBER_OF_FATS = 2

SECTORS_PER_FAT = 1
SECTORS_PER_ROOT = 1
;This was taken from a post on the fasm message board
NUMBER_OF_CLUSTERS = (NUMBER_OF_SECTORS-RESERVED_SECTORS-(NUMBER_OF_FATS*SECTORS_PER_FAT)-SECTORS_PER_ROOT)/SECTORS_PER_CLUSTER
REPEAT (((NUMBER_OF_CLUSTERS+1)/2*3+3)+BYTES_PER_SECTOR-1)/BYTES_PER_SECTOR
NUMBER_OF_CLUSTERS = (NUMBER_OF_SECTORS-RESERVED_SECTORS-(NUMBER_OF_FATS*SECTORS_PER_FAT)-SECTORS_PER_ROOT)/SECTORS_PER_CLUSTER
if (((NUMBER_OF_CLUSTERS+1)/2*3+3)+BYTES_PER_SECTOR-1)/BYTES_PER_SECTOR > SECTORS_PER_FAT
SECTORS_PER_FAT = SECTORS_PER_FAT+1
end if
END REPEAT

SECTORS_PER_ROOT = SECTORS_PER_ROOT+(NUMBER_OF_SECTORS-RESERVED_SECTORS-(NUMBER_OF_FATS*SECTORS_PER_FAT)-SECTORS_PER_ROOT)-(NUMBER_OF_CLUSTERS*SECTORS_PER_CLUSTER)
ENTRIES_PER_ROOT = SECTORS_PER_ROOT*BYTES_PER_SECTOR / 0x20


jmp beginning
nop ;To fill the first 3 bytes of fat12


OEMName db 'MSWIN4.1'
BytesPerSec dw BYTES_PER_SECTOR
SecPerClus db SECTORS_PER_CLUSTER
RsvdSecCnt dw RESERVED_SECTORS
numFats db NUMBER_OF_FATS
RootEntCnt dw ENTRIES_PER_ROOT
TotSec16 dw NUMBER_OF_SECTORS
Media db MEDIA_DESCRIPTOR
FATSz16 dw SECTORS_PER_FAT
SecPerTrk dw SECTORS_PER_TRACK
NumHeads dw NUMBER_OF_HEADS
HiddSec dd 0
TotSec32 dd 0
DrvNum db 0
Reservered1 db 0
BootSig db 0x29
VolID dd 0x33333333
VolLab db 'NO NAME    '
FilSysType db 'FAT12   '

beginning:
 ;Your code here

Attached is a PDF explaining the Fat Format which also explains how this works. It covers FAT12, FAT16 and FAT32.

18

Operating System Development / OS Development Forum Information

« on: June 19, 2005, 06:36:20 pm »

Anything having to do with OS Development or other low level programming can be posted here.

Rules:
1. Try to stay on topic
2. No personal attacks

Hopefully this will be simple enough that everyone can follow it!

19

Operating System Development / Zorm's OS

« on: June 18, 2005, 04:35:04 am »

So I reread lots of stuff about OS Development and started coding.

Code: [Select]

use16
org 0x7C00

beginning:
cli ;disable interrupts
xor ax, ax
mov ds, ax
mov es, ax
mov fs, ax
mov sp, 0x0fff0 ;Setup stack

;set 320x200 Color display mode
mov ax, 4
int 10h

push 21
push loadingString
call putString

hang:
jmp hang

putString:
mov bp, sp
mov dh, 1 ;row
mov dl, 0 ;column
mov al, 1 ;mode
mov bl, 0x07 ;display attribute
mov ah, 0x13 ;Write String
mov cx, [bp+4] ;String length
mov bp, [bp+2] ;String
int 0x10
retn

loadingString db 'Zorms OS Loading...', 13, 10

emptySpace = 510 - ($ - $$) ;Can be $$ or beginning
times emptySpace db 0
dw 0xAA55

Tested in Bochs it just prints a message right now and yes I realize putString clobbers stack and such but ill fix that later.

Edit:
I should point out this is for FASM as thats what im using.