Note: Descriptions are shown in the official language in which they were submitted.
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Software for restricting other software to be used
by the rightful user only and method therefor
Field of the invention
The present invention relates to protection of commercial software, and
particularly, to protection of such software against unauthorised use or
copying.
Background of the invention
Conventionally, software protection methods for protecting commercial
software products such as programs, multimedia software, distributed through a
communication network, such as a telephone system, require a user computer to
have
a piece of hardware comprising decryption keys and system be installed
therein, for to
be authenticated by a software program running on the computer. Hardware,
rather
than software, are being used because software duplication facilities are
commonly
found in personal computers. However, this is extremely cumbersome and places
a
large burden on users and vendors alike.
It is therefore an object of the present invention to provide a piece of
software
to replace the above-mentioned piece of hardware and the rightful user of that
piece of
software is being discouraged from copying it to someone else, by means of a
psychological barrier.
It is therefore another object of the present invention is to provide a method
to
discourage a rightful user from copying his software to someone else.
CONFIRMATION COPY
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Summary of the invention
According to a first embodiment of the present invention, there is provided a
central program comprising 1) a sub-program for providing an Encrypted
Identity
(herein below referred to as EI sub-program), 2) a sub-program for
authorising use of a software product (herein below referred to as AS sub-
program), 3)
a sub-program for authenticating user computer (herein below referred to as AC
sub-
program).
The central program is for managing the use of the individual sub-programs
therein so that the AS sub-program can be protected from being accessed
directly,
thereby preventing it from being copied individually. The EI sub-program is
for
providing identity information(an encrypted identity) of its rightful owner
for
accessing a network central computer to obtain services or software products
or alike
in which a secure operation on a user account of that owner for payment
therefor
involved. The AC sub-program is for authenticating the computer on which it
runs as
being a particular predetermined computer, by determining the hardware and
software
characteristics of that computer by software means and comparing the result
with that
required. The AS sub-program is for using the authentication result of the AC
sub-
program and the existence of the EI sub-program which being not protected
against
unauthorised use and being capable of being used by any user thereof, on a
computer,
as preconditions for authorising those software products obtained to be used
on that
computer.
It should be noted that in the central program, as far as protection of the
software products from being unlawfully copied by the rightful user to someone
else
is concerned, the AS sub-program is the only sub-program which needs
protection and
according to the present invention, the AS sub-program is protected from being
unauthorised copied by its rightful user to someone else lies on the fact that
a rightful
user would not copy a software, i.e., the central program in which the EI sub-
program
exists and which can be used by an unauthorised user to provide the rightful
user's
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identity information for using the rightful user's account in obtaining, for
e.g., network
services or software products, to someone else. As seen from the use of
automatic
teller machine(ATM) magnetic cards, which although can readily be forged, has
been
proved to be remarkably secure.
According to a second embodiment of the present invention, the central
program comprising the EI sub-program only, and the AS sub-program become an
individual program which authorises the software products) to be used only
when the
EI sub-program exists in the same computer it runs and which is being
determined by
receiving an encrypted identity of the EI sub-program from the same.
According to a third embodiment, the EI and AS sub-programs are basically
equivalent such that copying the AS sub-program by its rightful user to
someone else
is equivalent to copying the EI sub-program to someone else, thereby
preventing the
AS sub-program from unauthorised copying or use.
Brief description of drawings
FIG.1 is a block diagram of the central program.
FIG.2 is a diagrammatic view of a program in which a part B thereof being
encrypted,
in RAM space.
Detailed description of the preferred embodiments
The present invention is directed to protecting software products) distributed
through a communication network, against unauthorised copying or use, and for
the
sake of simplicity, the following description is directed to protection of
such software
products) stored in a user's IBM PC computer. And, the present invention will
be
described under the following headings:
1 ) The Central Program.
2) The Sub-program for providing an Encrypted Identity (EI sub-program).
3) The Sub-program for authorising use of a software product (AS sub-program).
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4) The Sub-program for authenticating user computer (AC sub-program).
5) Other Embodiments.
1 ) The Central Program.
According to the first embodiment, there is provided a central program which
being an executable program and can be caused to be executed a) by user by
entering
its filename in DOS environment, b) by a running program. FIG.1 is a block
diagram
of the central program, details are provided as follows
a) If a user desires to access a network central computer through a
communication link, the user has to cause the central program to be executed.
The
central program will request the user to enter a password to enable its
operation and if
the password coincidents with that required, it will be responsive to user's
commands) to send an encrypted identity of its rightful user, who should be
that user,
to the central computer.
This requirement of user password is necessary to prevent someone to access
the central computer and use the account of the rightful user without his
authorisation.
The central program will cause the EI sub-program, of which details will be
described herein below, to be executed for providing an encrypted identity of
the user,
to the central computer. The central computer will permit the access request
from the
user if the encrypted identity is correct, for which details will be described
in item 2
herein below.
b) When a running program desires to cause the AS sub-program to be executed,
to authorise it to continue to run, it will first prepare an input parameter
for indicating
to the central program such a request and store the input parameter in a
predetermined
location in RAM, then through the use of a PC DOS service call for that
purpose,
cause the central program to be executed. If the central program is being
enabled
previously by the above-mentioned password, it will access the input parameter
in the
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predetermined location and from it the central program can determine that a
running
program is requesting for an authorisation command from the AS sub-program,
and
will then cause the AS sub-program to be executed. Otherwise, the central
program
will not cause the AS sub-program to authorise the running program to continue
to
run. As the password is a password for enabling use of AS sub-program, as well
as the
EI sub-program, the rightful use is discouraged from providing the password to
someone else, in order that the someone else can use his AS sub-program.
For the case the central program is being caused by user to be executed, there
will be no valid or no input parameter and the central program can thus know
this fact.
2) The Sub-program for providing an Encrypted Identity (EI sub-program).
This sub-program uses the method used in IC credit card for identity
authentication and in which an encrypted identity is generated.
When starts, the EI sub-program sends an access request to the central
computer which in return will send back a random number. The EI sub-program
will
then encrypt the random number with a predetermined algorithm A 1 and send the
result to the central computer which will permit access if the result is
identical with
another result it obtained by performing the same encryption algorithm on that
random
number.
It should be noted that for each user, there is a corresponding respective
encryption algorithm A1 for the identity authentication thereof and also that
the
central computer may use the encryption result received from the EI sub-
program, if it
being correct, as a user authorisation for payment to be made, from a user
account for
obtaining network services or software products or the like.
3) The Sub-program for authorising use of a software product ( AS sub-
program).
According to the present invention, there are 2 approaches for authorising a
software product to be used
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i) by sending encrypted command to a running software program for authorising
it to
continue to run on a computer, in a similar manner as that mentioned above in
item 2
for identity authentication. Specifically, the running software program
includes in the
input parameter, as mentioned above in item 1b, a random number it generated,
then
causes the central program to be executed. The AS sub-program, which being
caused
to be executed by the central program, as mentioned above in item 1b, sends
the result
it obtained by performing a predetermined encryption algorithm A2 on that
random
number, to the running software program which will accept the encrypted
command
and continue to run, if the result is identical to another result it obtained
by performing
the same encryption algorithm A2 on that random number.
It should be noted that continuous use of the software program requires
continuously receiving encrypted commands.
It should also be noted that for each user, each of the software products for
use
on his/her computers) use a same respective encryption algorithm A2 and the
encryption algorithm A2 being included into each such software product by the
central
computer at the time when the central computer is to supply the same to the
user
computer.
ii) by decrypting an encrypted part of a software product or a completely
encrypted
software product.
It should be noted that if the software product is a program, then it will be
sufficient to have a part thereof to be encrypted, for preventing unauthorised
copying
and use, however, if the software product is an audiovisual multimedia data
file, it
should be more desirable to have the whole software product be encrypted.
The decryption of a part of or an entire software product takes place on a
temporary copy of which in RAM, and that temporary copy should no longer exist
after user finish using the software product, so as to prevent illegal copy
from being
made. Given by example only, FIG. 2 is a diagrammatic view of a program in RAM
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space, with a part B thereof being encrypted. As seen, the AS sub-program
decrypts
part B and stores the result which size should be not equivalent to that of
the
encrypted copy, in 'part B decrypted'.
The AS sub-program then overwrites at the first location of 'part B encrypted'
an instruction 'JUMP TO part B decrypted' and at the end of 'part B decrypted'
appends an instruction 'JUMP TO part C'. In this way, the encrypted part of
the
software will not be executed and the decrypted part will be executed instead.
In the case of audiovisual multimedia software, the software will be decrypted
a small part by a small part and each small part is decrypted at the time it
is about to
be utilized by a audiovisual program for causing audiovisual effect. In other
words,
that audiovisual program has to cause the AS sub-program to be executed in the
manner as described above in item 1b, everytime it wants a decryption of a
small part.
Desirably, a newly decrypted small part will overwrite a previously decrypted
one so
that a whole copy of the decrypted software will not exist in RAM.
4) The Sub-program for authenticating user computer (AC sub-program).
The AC sub-program for authenticating a computer on which it runs as being a
particular predetermined computer, and prevent use of protected software if
the
computer is not, and its operation is under control of the central program.
Specifically, when the central program is being installed in a harddisk of a
user
computer and executed, it will check an encrypted status information stored in
itself
and from which it knows this is the first time it being executed and will
cause an
initialization process to take place. In the initialization process, the
central program
sends to the central computer, as mentioned herein above in item 2, an
unencrypted
identity of the rightful user of the central program, then the AC sub-program
requests
for an encrypted command from the central computer which will provide such an
encrypted command, in the manner as described herein above in item 3i, if the
rightful user has a valid account which is not closed.
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After authenticating the command, the AC sub-program determines the
hardware and software characteristics of the user computer, which includes,
for e.g.,
identities of peripherals such as mouse, printer, joystick, harddisk and
floppy disk
drive etc.; running speed determination which is a function of CPU frequency,
cache
memory size etc.; number and number of heads, cylinders, sectors of harddisk
and
locations of bad sectors therein; version number of operation system software
and
physical position of a particular software product including the central
program in the
harddisk; hardware identity code or th like of the computer ; by skills well
known to
those in the art. For instance, the running speed can be determined by causing
the
computer to execute a test program and initializing a hardware counter to
measure the
time the computer has taken to finish executing the program. For another
instance, the
version number of the operation system may be determined by using a particular
DOS
service call.
The result of the determination and a status information indicative of the
central program being initialized will be stored by the AC sub-program in a
predetermined part of the central program in the harddisk, in the form of
encrypted
data. Thereafter, everytime when the central program is executed, it will
first check
the status information, and after determining that it is being initialized, it
will perform
a job as requested, as mentioned in item 1 herein above, and in addition
thereto, it will
also automatically cause the AC sub-program to be executed which will
determine at
least a part of the above-mentioned hardware and software characteristics of
the
computer on which it runs, at a time, and the AC sub-program will encrypt an
indication information in another predetermined part of the central program
for
causing the AS sub-program not to operate, if any part of the characteristics
determined is not identical to the corresponding part of that it encrypted and
stored
previously.
In addition thereto, the AC sub-program will also reset the encrypted status
information so that another initialization process will automatically take
place when
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the user causes the central program to be executed, and for the authorisation
of which
another encrypted command from the central computer will be required. This
encrypted command should be provided free of charge or a service charge
comparatively small compared with value of the protected software.
This prevents a user from deliberately adapting the central program to
computer of other user(s), after closing his account.
In addition, the encrypted command from the central computer may
alternatively be supplied to the user via, e.g., a telephone line, and then
entered into
the user computer by the user. Specifically, to request for an encrypted
command, the
AC sub-program generates a random number and conveys the random number to the
user who in turn supplies it to the central computer by means of telephone
dual tone
signals, generated by entering the random number on a telephone keypad,
through the
telephone line, and after encrypting the random number, the central computer
sends
the result to the user via the same telephone line by means of a voice
synthesizer.
5) Other Embodiments
According to the second embodiment, the AS sub-program is separated from
the central program and become an independent program, whereas the central
program
comprises the EI sub-program only. The AS program is bound to the EI sub-
program
by requiring the AS program to operate only when the EI sub-program exists in
the
same computer. Specifically, the AS program when running, can cause the EI sub-
program to be executed for generating an encrypted identity for the AS program
to
authenticate. The EI sub-program knows that this is a request for encrypted
identity
from the AS program, not a request from user for encrypted identity for
accessing the
central computer, by the method of input parameter as mentioned above in item
1b.
Further, the EI sub-program before sending the encrypted identity to the AS
program, may first check the data integrity of itself by, for instance,
checksum
method. Alternatively, it may also be that the AS program performs the
checking.
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And, if the checking result is that some data in the EI sub-program being
altered, then
in the former case, the AS will be caused to be not operable by the EI sub-
program by
not sending it an encrypted identity, and in the latter case, the AS program
will be
caused to be not operable by itself.
According to the third embodiment, the encryption algorithms A1 and A2 that
the EI and AS sub-programs use respectively for providing an encrypted
identity to
the central computer and for generating encrypted commands to authorise use of
a
software product respectively, is a same algorithm.
Thus, it would be equivalent for a rightful user to copy his EI sub-program to
someone else if he copies his AS sub-program to someone else. In this case, a
slight
modification on the AS sub-program can make it equivalent to the EI sub-
program
and which involves adding a simple interface program for receiving a random
number
from the central computer, feeding the random number into the AS sub-program,
receiving the encryption result from the AS sub-program and supplying the
encryption result to the central computer, and such functions are commonly
found in
any network interface software. Alternatively, the A1 and A2 algorithms may be
2
different algorithms, but information representative of the A1 algorithm is
being
included into the AS sub-program and be accessible by user or when the AS sub-
program being executed, capable of being used by AS sub-program to perform the
corresponding encryption function which being user-usable.
In addition, according to another embodiment of the present invention, the
software products and AS sub-program each includes an identity of its rightful
user,
so as to facilitate legal action against piracy. Further, the AS sub-program,
when
executed, will access each of the software products, by using a particular DOS
service
call for loading a software product stored in the computer on which it runs,
from
harddisk to RAM, one by one, for checking such an identity therein, if any
software
product is found to have an identity not identical to that of the AS sub-
program, the
AS sub-program will inhibit use of all software products under its control,
including
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itself, on the computer. Such identities may be stored in a predetermined
location of
the software products, and is protected from being altered by having an
encrypted one
stored in another location in each software product, and each of those another
locations is different in different software products so that it would not be
discovered
and altered. And, each such software product, when executed, will
automatically
check the unencrypted identity stored therein against the decryption result of
the
encrypted one, if they are not consistent, the software product will fail to
operate. The
identity or encrypted identity of the rightful user being included into each
of the
software products by the central computer at the time when the central
computer is to
supply the same to the user computer. Further, to prevent the AS sub-program
from
mistakenly regarding a software product which stored in the computer and which
being not supplied from the central computer, as a software product under its
control,
the central computer may further include information in a third predetermined
location
of each software product for indicating this fact, that is, the software
product being
supplied from the central computer, to the AS sub-program and each software
product
will not operate if when being executed, it finds that information therein
being altered.
