DAT VAN DE Yen ciiu cluing d6i voi be th6ng quan ly phong nuiy c6iig cgng lai mgt truiing dai bgc, do la CO the sir dung l6l trong dieu kien ha tang hien co, sir dung tai khoan ciia sinh
Trang 1Nguyen i'ran Quoc Vinh Tap chi KHOA HOC & CONG NGHE •71(9): 81 -87
M O T SO VAN DE TRONG XAY DLTNG HE THONG QUAN LY
PHONG M A Y CONG CONG
, , Nguyin Tran Quoc Vinh"
Tnrdng Dai hoc Kinh li' - Dai hoc Dd \ dng
lOM 3 AT
He thing quan ly viec sinh vien su dung may tinh tcii phong may cong cgng a cac tnrang dai hge
la cin thilt Yeu clu chung dii vai mot he thong la tich hop tot dieu kien ha tang hien co, kha
nang phat triln, ma rgng va sii' dung tai khoan ciia sinh vien de quan ly tii' ca sa du lieu thong nhat
ciia truong Co thi noi cac he thing hien co tren thi truang khong dap img yeu cau Bai viet lam
ro cac ky thuat cin thilt dl xay dung he thing quan ly phong may dam bao Ccic tinh iicIng: Quan ly
thai dilni sinh vien su dung may tinh Quan ly thai lugng sinh vien su dung may tinh mien phi va
theo the Quan ly cac dia chi internet ma sinh vien truy cap Cong cu de bat va tat may tinh tir xa
theo y niuon ciia quan tri vien
Til' khoii: Quan ly phdng mdy dich cu NT, truyin ihdng diep, che dp khdng ddng bg, dn lien trinh, hdt gdi lm vd dja chi hdt tdt mdy linh tirxa
DAT VAN DE
Yen ciiu cluing d6i voi be th6ng quan ly
phong nuiy c6iig cgng lai mgt truiing dai bgc,
do la CO the sir dung l6l trong dieu kien ha
tang hien co, sir dung tai khoan ciia sinh vien
(SV) de quan ly tir co so dir lieu thong nhcit
ciia truang Va sau day la cac yen can linh
nang ciui yen:
- Quan ly thai diem SV sir dung miiy linh
- Quan ly thai lugng SV sir dung nuiy tinh
mien phi va theo the
- Quan ly cac dja chi internet nui SV truy cap
- C6ng cu de bat va tat may tinh tir xa theo y
muon ctia quan trj vien
Nhin chung, yeu cau dciu lien va thir ba cho
phep dap irng eac doi boi dang duge ap dung
thuc lien eiia Thong tu lien tjch 02 Ve viec
qiiciii ly diem truy cap Internet do la Luu tru
thong lin tiiy than khach hang va Luu trfr
th6ng tin dja chi Web khiich himg truy Ccip
Tim bilu mgt so he tb6ng chuong trinh
thuong mai ciing nhu mien phi lien quan co
mat tren thj truang INCMWin, icaffe, cho
thay, hAu nhu cac phan mem quan ly Internet
Cafe diu c6 dac diem chung ki thuang se
khong luu dugc thong tin tinh lien khi nicil
dien Vi vay, dl he thong kh6ng bj nuit lh6ng
' let: 0914 780898: Email iihiiiocvinhaymail com
tin quan trgng nay khi mat dien, Ccic lac gia ciia cac chuong trinh do khuyen cao khach hang nen sir dung bg luu dien UPS tai may chii Khi mat dien, loan bg tluing tin linh tien van ducic luu lai va co the thuc hien thanh loan cho khach hang
Phan tich mgt s6 chuong trinh khac nhu Nel Support for School, WinRoule, Wingale, cho thiiy, khong co mgt be tluing hay to hcip cac he th6ng chuong trinh nao dap irng day dil cac yeu cau dat ra Ngoai ra, cac he th6iig dong thi kli6iig the can thiep, phat trien mo rgng va tich hgp co' so du lieu eiia truang Ve lau dai, can phai tlurc bien cac nghien ciru thong ke viec sir dung may tinh ciia nhung nhom nguoi dimg - SV nao do thong qua thai gian, thoi lugng, va hanh vi sir dung be lli6ng (chuong trinh trang web truy cap, ) ciia hg dugc luu lai trong co' sa dfr lieu Tren co' so ket qua cac nghien ciru do c6 the lap ke hoach sir dung cac phong may hieu qua nhat ciing nhu nhac nlia/kliiiyen khich SV ve cac hanh vi sir dung phong may ciia hg Cac he th6ng ma ngu6n incV thi chii yeu dugc tao ra cho nen tang Linux, trong khi he tluing may linh ciia cluing la hau nhu chi su dung Windows Ngoai ra, co the se can tliiiit phat trien va tich hgp cac tinh nang mcii, nlur quan
ly in an Fir nhung nhcin djnh tren co thi;
Trang 2Nguyen Tran Quoc \'inh Tap chi KHOA HQC & CONG NGHE 71(9): 81 -87
ket luan nghien ciru xay dung mgt he th6ng
mcii la Ccin thiet
M Q T SO VAN DE KY THUAT
Trong thiet ke \a phat trien bcit cir he th6ng
nao deu co nhirng van de Mgt khi da giai
quyet nhirng van de do, viec xay dirng he
thong khong con kho khan nira Theo cac
chirc nang yen cau da dua ra ro rang, de xay
dung he thong nay truac tien phai tra loi cac
can hoi sau day: Lam the nao de may chu
(MC) dai dien la chuong trinh may ciui
(CTMC) va max tram (MT) dai dien la
chu'O'ng trinh may tram (CTMT) co the "noi
chuyen" \ai nhau? Thu thap cac dja chi
internet ma SV da truy cap trong phien lam
viec ciia minh bang each nao? Lam the nao
de bat/tat hang loat cac MT chi bang mgt
lenh tir mgt may khac? Ngan can SV tat
CTMT nhu the nao?
Dam bao truyen thong giiia C T M C va cac
CTMT
Hoan tOcin co the giai quyet \an de truyen
th6ng gitia CTMC Vci CTMT lh6ng qua cac
thong diep chira cac leiih,/yeu cau tir/den
CTMC din/tir CTMT
C6ng viec ciia CTMC la gui nhan, va xir ly
th6ng diep den lir CTMT Can giai quylt viec
d6ng bg boa qua trinh giri/nhan th6ng diep va
xir ly ket qua de kh6ng xay ra tranh chap va
loi trong he th6ng CTMC Cac m6i truong
phai trien phan mem theo mac djnh thuang
lao ra mgt chuong trinh moi chi bao g6m mgt
lien trinh va qua trinh xii ly cau lenh trong
chuong trinh xay ra mgt each n6i tilp Khi do,
chuong trinh co the lam viec kh6ng hieu qua
\ci dac biet co the gay ra loi trong mgt so
irirong hgp Cach giai quylt la xay dyng
chuong trinh da tien trinh (multi-threading)
\ci dimg cac d6i tugng giiip dong bg hoa qua
trinh truy cap den cac tai nguyen dimg chuna
ciia nhieu lien trinh khac nhau nhu mutex,
semaphore, event, interlock trong thu vien
WIN API Cac moi truong lap trinh ngay nay
deu CO Ccic lap khac nhau trien khai Ccic chirc
nang tuong irng
Windows Sockets 2 (WinSock) [1-3] cho phep
Icip trinh de tao cac img dung Internet, IntraneL
va cac iing dung mang de truyen dCr lieu, doc lap vai cac giao thirc mang dugc sii' dung
De dam bao CTMC co the lam viec cimg liic vai nhieu CTMT, tac gia da sir dung WinSock trong che do kh6ng dong bg (asynchronous mode) Trong che d6 nay CTMC la mgt lien trinh - tien trinh chinh co the tao them m6t tien trinh con de thuong xuyen kiem tra sir xual hien mgt th6ng diep den tir CTMT Va cho in6i mot th6ng diep nhan dugc tir CTMT mgt lien trinh con nua dugc tao ra de dam nhan viec xu K' no
Va bay gia, su xung dot trong sir dung tai nguyen giua cac tien trinh la hoan loan co the xay ra Tac gia sir dung lop Monitor va lockobject de dam bao su d6ng bg hoa truy cap den tai nguyen chung cua cac tien trinh
Tuy CTMT chi dam bao truyen th6ng voi mgt dau in6i duy nhat la CTMC, Socket dugc sir dung trong no cung dugc tao ra trong che do kh6ng dong bg
Trong in6i lli6ng diep giua CTMC va CTMT chira mgt lenh la ni6t tii' khoa cimg voi cac th6ng s6 ciia no Lenh va cac th6ng s6 dugc phan each voi nhau bang cac ky tu khoa De ban die truong hgp "tan c6ng tii' ch6i djch vu" do dai ciia th6ng diep dugc gioi han th6ng qua cau hinh ciia CTMC Vi the, nhirng th6ng diep nhu danh sach dja chi SV da truy cap bay Ijch sir sir dung may tinh ciia SV co the dai hon so voi chieu dai gioi ban Chimg
se dugc cat ra va giri den may nhan theo nhieu th6ng diep khac nhau
M6i thong diep dugc tinh t6ng CRC32 triroc khi giri T6ng nay dugc dinh kem voi thong diep Khi CTMC/CTMT nhan dugc thong diep tir CTMCT/CTMC n6 se kiem Ira long CRC32 ciia th6ng diep co dimg hay khong, Neu dimg no se tien banh xir ly Neu sai nghTa la th6ng diep vira nhan kh6ng chinh xac, no se bao lai cho ben giri ve sir kien nay
de ben giii giri lai thong diep mgt lan nfra Trong truong hop th6iig tin giri di dugc xep vao loai nhay cam, chang ban login, mai khau, no se giri cho may nhan lh6ng diep do qua kenh ma boa SSL Liic Uciy tinh CRC32
cho thong diep la dieu kh6ng ckn thill \ i thucit
loan SSL da tinh den sir chinh xac Irong lru>en tai ciia thong diep dugc ma hoa
Trang 3Nguyen Tran Quoc Vinh Tap chi KHOA HOC & CONG NGHE 71(9): 81 - 8 7
Quan ly dja chi internet SV da truy cap
Vi SV CO the sir dung nhieu chuong trinh
khac nhau, co the co san tren MT, co the tai
ve tir internet hay mang den tren cac luu trir
USB la kh6ng the bat tat ea cac dja chi
internet ma SV truy cap tli6ng qua phan tieh
mgt s6 chuong trinh, ma can phai bat cac goi
tin TCP/IP dugc truyen tai qua cac the giao
dien mang (NIC) va phan tich T6n tai mgt s6
c6ng nghe de bat cac goi tin TCP/IP lieu bilu
la Microsoft Filter-hook driver,
Firewall-Hook Driver, NDIS - Network Driver
Interface Specification va WinPcap - The
Windows Packet Capture Library
Filter-hook la mgt trinh dieu khien che do hat
nhan dugc sii' dung de Igc cac goi mang Chi
duy nhat mgt filter-hook co the dugc cai dat
tren he dieu hanh va dugc sii' diing boi cac bg
Igc Irinh dieu khien IP Ta co the phat trien
mgt luong lira hoac mgt monitor, nhung neu
cac img dimg khac sir dung bg Ige nay va cai
dat cac chirc nang trucic, cbiroiig trinh ciia
cluing ta se kh6ng liuii ducjc bat cir dieu gi va
ngugc lai Mac dii lai lieu hircing diin DDK
noi rang, eo the truy cap goi ngi dung trong
mgt bg Igc dang boat dgng Nhung tlurc te, la
chi CO the truy cap g6i ngi dung cho cac goi
nhan dugc, con d6i voi Ccic goi da giri la chi
CO the dgc diu FCP/IP, UDP Vci ICMP
Muc dich ciia Firewall-Hook lii cte quan ly cac
goi niciiig da ducic giri va nhan dugc tren mgt
birc luang lira trong b6i canh ciia cac giao thirc
TCP/IP No Cling co the can thiep vao hocit
dgng ciia cac ket n6i chia se Internet (ICS),
hoac mgt birc tuong lira ca nhan dang thuc thi
I iiy nhien, no khong dap irng yen Cciu cua birc
luong lira boi vi n6 chay 6 tan qua cao trong
mo hinh nicing Firewall-Hook kh6ng dugc
khuyin cao de trien khai cho MS Windows XP
va cac phien ban sau ciia he dieu hanh nay
Ro rang, niu sir dung Firewall-FIook Driver
thi se gap kho khan cho phat trien mo rgng he
Ihong vl sau De cung Ccip chirc nang tuang
lua tren Windows XP va cac phien ban sau
ctia n6 nen Lio m6t trinh dieu khien trung
gian miniporl NDIS de quan ly cac goi da
giri vii nhan
Trinh dieu khien trung gian NDIS [4] lam viec tren giao dien giiia cac cap do giao thirc dieu khien va trinh dieu khien miniporl No
CO the dugc irng dimg de a) Bien djeh giu'a
cac trinh dieu khien thugc cac tang khac nhau;
b) Lgc du' lieu vi muc dich an ninh hay cac miic dich khac; c) Giai phap dieu chinh can
bang tai (LBFO); c/) Giam sat va thu thap dir lieu lh6ng ke cua mang
Mgt trinh dieu khien miniport true tiep quan
ly mgt NIC va cung cap mgt giao dien voi trinh dieu khien 6 mirc cao hon Hau nlur cac ung dung mang ii6i tieng deu irng dung NDIS Chang ban, kiem tra the Network Adapters trong Device Manager eiia MS Windows va cho hien tat ca cac thiel bj an ta
CO the ihay Kaspersky Internet Security quan
ly cac goi mang bang each tao ra cac NDIS Miniport cho tirng NIC Co the noi, NDIS co rat nhieu uu diem Tuy nhien, sir dimg no la hoan loan kli6ng don gian doi hoi rat nhieu c6ng sire trong khau lap trinh Dc dam bao cac yen cau dat ra ta co the sir dimg WinPcap voi su don gian hon trong lap trinh
WinPcap [5] la lieu chuan c6ng nghiep cho cong cu cung cap kha nang truy cap mang thugc lap lien ket trong ni6i truoiig Windows:
no cho phep cac img dung nam bat va truyen tai cac goi mang bo qua cae chong giao tluic
va CO them cac tinh nang huu ich bao gom Igc goi cV cap do hat nluin may tli6ng ke mang
va c6ng cu Ii6 trg cho chup goi tir xa, WinPcap bao g6m mgt trinh dieu khien cho phep nici rgng he dieu hanh dc cung cap kha nang truy cap mang ci mirc do thap, va mgt thu vien dugc sir dung de de dang truy cap vao lop mang cap do thap Thu vien nay cfmg chira cac phien ban ciia Windows cung nhu phien ban dugc biet den rgng rai la libpcap UNIX API
Nha sir phong phii ve linh nang, WinPcap lii may bat goi va c6ng cu Igc ciia nhieu cong cu mang ma ngu6n ma va thuong mai bao gom
ca giao thirc phan tich, gicim Scil vii theo doi mang monitor, sniffer, luu lugng truy c;ip mang va c6ng cu kiem thir mang Mgt s6 trong nhung c6ng cu nay, nlur Icpdump WinDump, Wireshark, Nmap snort, nlop riil
Trang 4Nguyen Tran Quoc Vinh Tap chi KHOA HQC & CONG NGHE 71(9): 81 -87 ket luan, nghien ciru xa\ dung mgt he th6ng
moi la can thiet,
M O T S O VAN DE KY THUAT
Trong thiet ke \a phat trien bat cir he th6ng
nao deu co nhting \an de Mgt khi da giai
quyet nhiing \an de do viec xay dung he
thong khong con kho khan nira Theo cac
chirc nang yeu cau da dua ra ro rang, de xay
dirng he thong nay truac lien phai tra loi cac
Cciu hoi sau day: Lam the nao de may chu
(MC) dai dien la chuong trinh may chii
(CTMC) va max tram (MT) dai dien la
chuo'ng Irinh max tram (CTMT) co the "noi
chuyen" \ai nhau? Thu thap cac dja chi
internet ma SV da truy cap trong phien lam
viec ciia minh bang each nao? Lam the nao
de bat/tat hang loat cac MT chi bang mgt
lenh tir mgt max khac? Ngan can SV tat
CTMT nhu the nao?
Dam bao truyen thong giiia CTMC va cac
CTMT
Hocin loan co the giai quyet x'aii de truyen
lh6ng giua CTMC \a CTMT tli6ng qua cac
tli6ng diep chira cac lenh'yeu can tir/den
CTMC dln,'tir CTMT
Cong viec cua CTMC la gui nhan, va xir ly
lli6ng diep den tir CTMT Can giai quyet viec
d6iig bg boa qua trinh giri/nhan th6ng diep va
xir ly ket qua de kh6ng xay ra tranh chap va
loi trong he tli6ng CTMC Cac m6i truang
phat trien phcin mem theo mac djnh thuong
tao ra mgt chuong trinh mai chi bao gom mgt
lien trinh \ a qua trinh xu ly can lenh trong
chirong trinh xay ra m6l each n6i tiep Khi do,
chuong trinh co the lam viec kli6ng hieu qua
va dac biet co the gay ra loi trong mgt s6
truong hgp, Cach giai quyet la xay dung
chuong trinh da tien trinh (multi-threading)
\ ci dimg cac doi tugng giiip d6ng bg boa qua
trinh truy cap den cac tai nguyen dimg chung
cua nhieu tien trinh khac nhau nhu mutex
semaphore, event, interlock trong thu vien
WIN API Cac moi truong lap trinh ngay nay
deu CO cac Icip khac nhau trien khai cac chirc
nang tuong irng
Windows Sockets 2 (WinSock) [1-3] cho phep
Icip trinh de lao cac img dung Internet IntraneL
va cac Ling dung mang de truyen du' lieu, dgc lap voi cac giao thuc mang dugc su' dung
De dam bao CTMC co the lam viec ciing liic voi nhieu CTMT, lac gia da su dung WinSock trong che do kliong dong bg (asynchronous mode) Trong che do nay CTMC la in6l lien trinh - lien trinh chinh co the tao them mgt lien trinh con de thuong xuyen kiem tra sir xuat liieii mgt lh6ng diep den tir CTMT Va cho moi mot thong diep nhan dugc tir CTMT mgt tien Irinh con nua dugc tao ra de dam nhan viec xu' ly nci
Va bay gio, su xung dot trong sir diing tai nguyen giua cac lien trinh la hoan loan co the .xay ra Tac gia sir dimg lop Monitor \a lockobject de dam bao su d6ng bg hoa truy cap den tai nguyen chung ciia cac tien trinh
Tuy CTMT chi dam bao truyen thong voi mgt dau m6i duy nhat la CTMC Socket dugc su dung trong no cung dugc tao ra Irong che do kh6ng d6ng bg
Trong m6i th6ng diep giua CTMC va CTMT chira mgt lenh la mgt tii' khoa cimg voi cac thong so ciia no Lenh va cac th6ng s6 dugc phan each voi nhau bang cac ky tu khoa, De ban che truong hgp "tan c6ng tii' ch6i djch vu" do dai ciia tb6ng diep dugc gioi ban th6ng qua cau hinh ciia CTMC Vi the, nhiing th6ng diep nhu danh sach dja chi SV da truy cap hay Ijch sir sir dung may tinh ciia SV, co the dai hon so voi chieu dai gioi ban Chiing
se dugc cat ra va giri den may nhan theo nhieu tli6ng diep khac nhau
Moi th6ng diep dugc tinh t6ng CRC32 truoc khi giri T6ng nay dugc dinh kem vai thong diep Khi CTMC/CTMT nhan dugc thong diep tir CTMCT/CTMC no se kiem tra long CRC32 ciia th6ng diep co dimg hay kh6ng, Neu dimg no se tien hanh xir ly Neu sai nghTa la th6ng diep vira nhan kh6ng chinh xac, no se bao lai cho ben giri ve su kien nay
de ben gui giri lai th6ng diep mgt lan nira Trong truong hgp th6ng tin giri di dugc xep vao loai nhay cam, chang ban login, mat khau, no se giri cho may nhan th6ng diep do qua kenh ma hoa SSL Liic luiy tinh CRC32 cho th6ng diep la dieu kh6ng can thill, vi thuat loan SSL da linh den su chinh xac trong truyen tai ciia thong diep dugc ma hoa
Trang 5Nguyen Trcin Quoc Vinh Tap chi KHOA HOC & CONG NGHE 71(9): 81 -87 Quan ly dja chi internet SV da truy cap
Vi SV CO the sir dung nhieu chuong trinh
khcic nhau co the co san tren MT, co thi tai
ve tir internet hay mang din tren cac luu tru
USB ta kh6ng the bat tat ca cac dja chi
internet ma SV truy cap th6ng qua phan tich
mgt s6 chuong trinh ma can phai bat eac goi
tin TCP/IP dugc truyen tai qua cac the giao
dien mang (NIC) va phan tich T6n lai mgt so
cong nghe de bat cac goi lin TCP/IP tieu bilu
lii Microsoft Filter-book driver,
Firewall-Hook Driver, NDIS - Network Driver
Interface Specification va WinPcap - The
Windows Packet Capture Library
Filter-hook la mgt trinh dieu khien che do hat
nhan dugc sii dung de Igc cac goi nuang Chi
duy nhat mgt filter-hook co the dugc cai dat
tren he dieu hanh va dugc sir dung boi cac bg
Igc trinh dieu khien IP Ta eo the phat trien
mgt tircTiig lira hoac mgt monitor, nhung neu
Ccic irng dung khac sir dung bg Igc nay va cai
dat cac chirc nang truoc, chuong trinh ciia
cluing ta se kli6ng liim dugc biit cir dieu gi va
ngugc lai Mac dii Uii lieu hircing diin DDK
noi rang, co the Iriiy ciip goi luii dung trong
mgt bg Igc dang hoat dgng Nhung Ihuc te, ta
ehi CO the truy cap goi ngi dung cho cac goi
nhan dugc, con d6i voi cac goi da giri la chi
CO ihci dgc diu TCP/IP, UDP Vci ICMP
Miic dich cua Fircvvall-Hook la de quan ly cac
goi mang da ducic gui va nhan duirc tren mgt
birc luang lira trong boi canh ciia cac giao thirc
TCP/IP, No Cling co the can thiep viio bocat
dgng ctia cac ket n6i chia se Internet (ICS),
hoac mgi birc tuang lira ca nhan dang thuc thi
I uy nhien, no kli6ng dap irng yen Cciu cua birc
tuong Ilia boi vi no chay 6 tan qua cao trong
mo hinh iiuaiig Firewall-Hook kluing dugc
khuyen cao de trien khai cho MS Windows XP
vii cac phien ban sau ciia be dieu hanh nay
Ro rcing, neu sir dung Firewall-Hook Driver
thi sc gap kho khan cho phat trien ma r6ng he
thong ve sau De cung cap chiic nang tuong
lua tren Windows XP va cac phien bcin sau
cua no, nen Uno mgt trinh dieu khien trung
gian miniporl NDIS de quan ly cac goi da
gui vii nhan
Trinh dieu khien trung gian NDIS [4| lam viec tren giao dien gifra cac cap do giao thirc dieu khien va trinh dieu khien miniport No
CO the dugc irng dung de a) Bien djch gifra
cac trinh dieu khien tliu6c cac lang khac nhau;
b) Lgc dti' lieu vi muc dich an ninh hay cac
muc dich khac; c) Giai phap dieu chinh can
bang lai (LBFO); ci) Giam sat va thu thcip dir
lieu thong ke ciia mang
Mgt trinh dieu khien miniport true tiep quan
ly mgt NIC va cung cap mgt giao dien vcii trinh dieu khien a iiiiic cao hon, Hau nlur cac irng diing mang n6i tieng deu irng dung NDIS Chang ban, kiem tra the Network Adapters trong Device Manager ciia MS Windows va cho hien tat ca cac thiet bj an ta
CO the ihay Kaspersky Internet Security quan
ly eae goi mang bang each tao ra cac NDIS Miniporl cho tirng NIC Co the noi, NDIS c6 rat nhieu uu diem Tuy nhien, sir dimg no la hoan loan khong don gian doi hoi riit nhieu cong sire trong khciii lap trinh Dc dam bao cac yen can dat ra, ta co the sir diing WinPcap voi sir don gian bon trong liip trinh
WinPcap [5] la tieu chuan cong nghiep cho cong cu cung cap kha nang truy cap mang thugc lop lien kel trong m6i truong Windows:
no cho phep eac irng dung nam bat va truyen tcii cac goi mang bo qua ciic chong giao tluic,
va CO them cac tinh luing huu ich, bao gom Igc goi a cap do hat nhan, may thong ke mang
va c6ng cu ho trg cho cluip goi tir xa
WinPcap bao gom mgt trinh dieu khien, cho phep 1110' rgng he dieu hanh de cung cap kha nang truy cap mang a mirc do thap, va mgt thu vien dugc su' dung de de dang truy cap vao lop mang cap do thap Thu vien nay cung chira cae phien ban ciia Windows cung nhu phien ban dugc biet den rgng rai la libpcap UNIX API
Nha su phong phii ve tinh nang WinPcap la may bat goi va c6ng cu Igc cua nhieu cong cu mang ma ngu6n ma va tlurong nuai bao gom
ca gicio thirc phan tich, gicim siit vii theo doi mang monitor, sniffer, luu lugng Iruy Ccip nuang va c6ng cu kiem thir mang Mgt so trong nhung c6ng cu luiy, nhu Icpdump, WinDump, Wireshark, Nmap, snort, nlop riil
Trang 6Nguyen Tran QuIc Vinh Tap chi KHOA HQC & CONG NGHE 71(9): 81 -87
noi tieng va dugc su dung rat rgng rai trong
cgng dong mang
WinPcap so huu nhieu dac tinh dang chu y
nhu mien phi, hieu qua boat dgng cao, ph6
bien rgng rai, da dugc kiem thir va dang tin
cay de dang sir dung cho lap trinh vien cung
nlur iigu'6'i dimg cu6i, dugc tich cue duy tri
lien hau het cac he dieu banh hg Windows, de
dang xuat khau cong cu UNIX hay Linux
sang Windows va ngugc lai Mcit khi da bat
dugc cac goi mang, ta co the phan tich chimg
de dua ra dja chi internet ma SV truy cap
tham chi, ca ngi dung cua cac goi tin do
Bat/tat may tram
Co nhieu c6ng nghe khac nhau h6 trg bat may
tinh tir xa qua LAN (Wake on LAN) hoac
Internet [6] Tac gia sir dung c6ng nghe ggi la
Magic Packet [7] Magic Packet la mgt goi lin
voi ngi dung 6 byte OxFF kit hgp vai 16 lln
dja chi MAC ciia NIC dugc gSn tren MT cin
bat Magic Paket dugc giri cho toan mang
LAN Khi NIC quet dugc Magic Packet voi
dja chi MAC ciia minh no se bat may tinh
Tat nhien, de NIC co the bat may tinh, trong
muc Power Management ciia BIOS Setup,
cin thill dat thugc tinh Wake On LAN vl
gia trj True
Xac djnh dja chi MAC ciia tit ca cac NIC
trong LAN va them vao danh sach la c6ng
viec kh6ng nuiy kho khan nhung doi hoi
nhieu c6ng sire Dae biet, khi so lugng may
tinh Ion va m6i khi co thay d6i NIC la phai
dieu ehinh danh sach MAC Ta co thi quel lat
ca cac nhom mang (WorkGroup) trong LAN,
sau do quel tat ca cac may tinh thugc moi
nhom [8] D6i vai m6i may tinh, diing lenh
SendARP [9] de nhan dja ehi MAC ciia no va
luu vao danh sach de dieu khiln bat may linh
tir xa diing Magic Packet
De lat MT, tac gia xay dung mgt chuong
trinh - djch vu NT va cai dat tren MT voi
quyen quan Irj vien Chuong trinh nay tu
dgng kel n6i den CTMC bang WinSock Khi
nhan dugc lh6ng diep chira lenh tat may vai
thong s6 la each thirc tSt may - PowerOff,
Shutdown, Hibernate hoac Suspend, no se
ggi chu6i cac lenh WinAPI dl tat may theo
kieu cp buoc [10]
Ngan SV tdt CTMT
Tb6ng thuong, cac he th6ng chuong trinh quan ly MT lam viec theo kjch ban sau Tai khoan Windows ma SV sir dung tren MT la lai khoan nguoi dimg bj gioi han chir khong phai la mgt tai khoan quan trj vien Va thuong, MT dirge cai dat de tir dgng dang nhap vao Windows bang lai khoan nay, Ngay sau do, CTMT se dugc khoi dgng va kh6ng che man hinh SV phai dang nhap thanh c6ng vao he tb6ng quan ly th6ng qua CTMT thi hg moi c6 the lam viec, voi dieu kien tai khoan ciia hg cho phep Ngugc lai, CTMT se chiem loan b6 man hinh va SV khong the lam viec tren MT
Van de dat ra la, neu SV tim each til CTMT lhi sao? Co the lira chgn "cam" chuong trinh Task Manager ciia Windows bang each thuc hien mgt s6 thiel dat trong he th6ng Registry ciia Windows dl SV khong thi tat CTMT Tuy nhien, lira chgn nay khong phai la diing dan Trong qua trinh sii' dung MT, co lhi ,xay
ra nhieu van de voi cac chuong trinh img dung, chang ban, cac iing dung van phong bj
treo la hoan loan co the Va SV can dimg
Task Manager de dong nhung chuong trinh
do Ngoai ra, niu chii tam tat CTMT, SV co the su' dung cac e6ng cu khac mang theo, chu' kh6ng nhat thiet phai dimg Task Manager Chimg loi thuc hien cac buoc sau dl ngan ngira SV tat CTMT D I U tien, xac djnh tat ca cac chuong trinh quet danh sach tiln trinh, chang ban nhu Task Manager Sau do giri
th6ng diep he thing LVMDELETEITEM 6i
xoa ten ciia CTMT tir danh sach tiln trinh ciia cac chuong trinh do [ I I ] Nhu thi, CTMT kh6ng CO ten trong danh sach liln trinh va SV khong the tat no Tuy vay, SV van co thi tSt true tilp CTMT bang mgt cong cu nao do chir kh6ng quet danh sach tiln trinh Nhu thi, CTMT "an minh" d6i voi cac c6ng cu kilu Task Manager la chira dii Giai phap dugc chgn la them tinh nang kilm soat viec tat CTMT boi mgt irng dung khac vao djch vu
NT ciia MT da d l cap 6 tren Vi dich vu NT nay lam viec duoi tai khoan quan trj vien
Trang 7Nguyen Tran Quoc VinI Tap chi KHOA HQC & CONG NGHE 7 1 ( 9 ) - 8^ hoac he th6ng nen SV kb6ng the tcii no Khi
SV tat CTMT no se bu6c SV thoat cua phien
lam viee (Log Off) hoac khoi dgng ep buoc
lai MT Kiem soat va thoat phien lam viec
lui> khai dgng lai may kb6ng the hoan loan
tha) the viec CTMT "an minh" d6i voi cac
cong cu kieu Task Manager, vi no de dan den
viec MT bj khai dgng lai thuong xuyen
Lua chon cong nghe
"fac gia lira chgn cong nghe WinSock de trao
doi thong tin dua tren TCP/IP; ma boa d6i
xirng va phi d6i xirng; CRC32 de kiem tra
tinh dimg dan ciia thong diep nhan dugc; xiiil
de luu ciiu hinh; lap trinh xir ly du lieu ODBC
- Open Database Connectivity; thir vien
WinPcap de bat cac goi lb6ng tin luu thong
qua NIC; iig6n ngfr lap trinh C# va moi
trircTng phat trien Visual Studio 2008 cho
phep xiiy dung he th6ng de dang nhat,
Ket n6i den iigu6n dfr lieu ODBC kli6ng phu
thugc vao he quan trj co' so dir lieu Cac bang
du lieu thugc ve rieng he th6ng nay, bang du
lieu tcii khoan SV cfing nhu cac thao lac ciia
he thong ducrc xay dung tren cac bang dfr lieu
do la don gian Vi the, co the lira chgn lap
trinh xir ly dfr lieu ODBC, va no cho phep su
dung bcit cir he quan trj ca so dir lieu hien co
Ucio, Xciy dung he lh6ng He Uuing chuong
trinh quan ly phong may va SV dimg be tli6ng
may tinh cua trucing dai ligc lioim thanh bao
gom cac thanh phiin chirc luing chinh va chia
liiin 4 giai doan phat trien sau day
Quiin Iy thoi diem SV sii' dung may tinh
Quan ly thai diem SV bat dciu su dung va ket
Ihiic phien lam viec tren mgt MT cu the:
- 'Uuing lin chinh Xcic ve MT nao da dugc sir
diing dugc km gifr theo s6 MAC ciia NIC
hocic la s6 sery cua 6 cimg (nhung s6 nay
kli6iig lap)
- Thong lin lai khoan SV dugc sir dung tir co'
so dfr lieu bg phan Dao tcio, Quyen truy cap
de dcic (chi dgc, khong sira d6i, them, xoa) do
bg phcin Dao tao cung cap,
- Khoang each giira hai kin Ccip nhat thong tin
truy cap ciia SV len co sci du lieu do quan trj
vien quy djnh qua phan mem quan trj
Chuong trinh bao g6m ba thanh phan ki CTMC c6ng cu quan trj cau hinh CTMC va CTMT,
- CTMC - Mgt djch vu he thong N'F tir d6ng khoi dgng va lam viec a cap do he tli6ng chju trach nhiem lien lac voi cac MT va MC ca so'
du lieu ciia bg phan Dao tao Neu mat kel noi den CO so dir lieu, CTMC se lien tuc thir ket noi den co' so dfr lieu theo nhfrng thong so da dugc quan trj vien cho trucic
-Quan tri cau hinh CTMC cho phep quan trj tir xa hoac ngay tren MC voi dieu kien ngiroi diing phai nhap dimg mat khau ciia quan trj vien No quan trj thong so ket noi gifra CTMC
va CTMT, tli6ng s6 ket noi cua CTMC den co
so dfr lieu cung nlur thong tin ve Ccic bang dir lieu, che do bao mat trong lien lac giira CTMC va cac CTMT (SSL2, SSL3, PTL), giai ban s6 ket noi CTMC cho phep cimg mgt luc, toi da 50.000 mill kluiii de ma kboii cac C'FMT khoang tbcii gian gifra hai lan cap nhiit thong lin sir dimg M F cua SV
-CTMT dugc cai dat va luon luon llurc thi tren M'F No chi cho phep SV lam viec neu
SV nhcip dimg lining tin mgi tiii khoan co trong CO' so dfr lieu ciia bg phan Dao tao Neu nhap dimg miit khau dc; ma khoa do quan trj vien quy djnh thi co the lam viec kh6ng can dang nliiip; cluic luing niiy nham pliiic vu ciic Icip bgc tai phong may
Quan ly thoi lu'ong SV sii' dung may tinh mien phi va theo the
- Moi SV dugc su dung mien phi mgt thai lugng trong mgt gioi ban ve thai gian nhat djnh dugc quy djnh theo tirng lop Cac giai luan nay dugc quy djnh bai mgt chucTng Irinh dugc cung cap la mgt phan ciia bg cong cii
- SVco the mua the va kich boat the Co mgt chuong trinh rieng de lao ra cac the voi so the
va mat khau ngau nhien theo cac th6ng s6 do nguoi sir dung chuong trinh cho trucic nhu: menh gia, thai lugng va gioi ban so ngay phai sir dung bet thai lu'cing Neu gcin kel tluic thai gian sir diing nhung tluii lucing van con nhieu,
SV CO the kich boat the khac de dirirc duoc phep su dung ca pluin chua sir dimg cua liii khoan The duoc ban a mot tluri diem vii