Title of Invention	" A METHOD FOR READING INITIALIZATION DATA INTO A CHIP CARD AND A METHOD OF GENERATING A RECORD FOR INITIALIZING A CHIP CARD"
Abstract	The invention relates to a method for reading initialization data (IND) into a chip card, according to which the chip card receives an encrypted authentication value (EAV) and decrypts the same in order to receive at least one enable key (ENK). Said enable key (ENK) is checked for its concordance with an enable key (ENK') stored on the chip card (14). If the keys concord, the initialization data (EIND, IND) are received and written into a non-volatile memory of the chip card. The invention also relates to a method for producing a data record used for the initialization of a chip card, according to which the chip card and a computer-readable data carrier have matching features. The invention is especially provided for the initialization of chip cards by external partners of the chip card producer, and is especially tamper-proof. (FIG.1).

Title of Invention

" A METHOD FOR READING INITIALIZATION DATA INTO A CHIP CARD AND A METHOD OF GENERATING A RECORD FOR INITIALIZING A CHIP CARD"

Abstract

The invention relates to a method for reading initialization data (IND) into a chip card, according to which the chip card receives an encrypted authentication value (EAV) and decrypts the same in order to receive at least one enable key (ENK). Said enable key (ENK) is checked for its concordance with an enable key (ENK') stored on the chip card (14). If the keys concord, the initialization data (EIND, IND) are received and written into a non-volatile memory of the chip card. The invention also relates to a method for producing a data record used for the initialization of a chip card, according to which the chip card and a computer-readable data carrier have matching features. The invention is especially provided for the initialization of chip cards by external partners of the chip card producer, and is especially tamper-proof. (FIG.1).

Full Text	A CHIP CARD AND A METHOD OF GENERATING A RECORD FOR INITIALIZING A CHIP CARD The present invention relates to a chip card and a method of generating a record for initializing a chip card and in particular to the compilation and processing of a record that is read into the chip card in an initialization step. [0002] Chip cards are well known in many embodiments. They are used for exam- ple for access control or in payment transactions and normally have a semiconductor chip with a microcontroller and at least one memory. Besides the usual designs in checkcard size or as small card modules (e.g. SIMs - subscriber identity modules in mobile phones), chip cards are also produced in other designs (e.g. as key pendants or rings). All these embodiments are to be referred to as "chip cards" in the present text. [0003] During production of chip cards, initialization is the method step by which, after completion and successful testing of the chip card hardware, those programs and/or data are imported into the chip card that are identical for a relatively large num- ber of chip cards. The subsequent step of loading personal, individual data is referred to as personalization. [0004] The separation of these two steps is effected for reasons of production engi- neering to minimize the quantity of data to be transferred individually into individual chip cards. In some cases of application, so-called post-initialization is inserted be- tween the steps of initialization and personalization, by which additional programs and/or data are written into a relatively small number of chip cards. An overview of these production steps and their delimitation is found in Chapter 10.4 (pages 584 to 592) of the book "Handbuch der Chipkarten" by Wolfgang Rankl and Wolfgang Ef- fing, 3rd edition 1999. [0005] According to an at least internal prior art of the applicant, chip cards for the GSM mobile phone system contain a 32-byte release key in a mask-programmed ROM of the chip card. To start the initialization process a data value matching the release key must be transferred to the chip card with a suitable command (e.g. VERIFY INI- TIALIZATION KEY). The transferred value is compared with the release key stored in the chip card ROM. In case of a match, access is released to an EEPROM of the chip card and all chip card commands required for initialization. [0006] Subsequent loading of initialization data into the chip card can be done ei- ther openly or encrypted with a load key. Encrypted loading ensures that the privacy of the encrypted initialization data is retained in case of unauthorized access. [0007] However, this system still involves the problem that the release key must be known to the authority performing initialization. It is increasingly required that not only the chip card manufacturer itself but also external partners (e.g. mobile phone network operators) initialize chip cards on their own. In this case there is a danger of the release key being spied out during transfer to the external partner or when it is read into the chip card, or of the external partner not keeping the release key strictly secret. [0008] If the release key were made accessible to unauthorized persons a whole chip card product line might possibly be compromised, because the release key per- mits access to diverse basic chip card functions which can in turn be used for spying out the chip card"s hardware and software. For example, if an unauthorized third per- son knows the release key he can load his own program code into the chip card and thus spy out the code already located in the mask-programmed ROM. : [0009] German laid-open print DE 196 33 466 A1 discloses a method for post- initialization of chip cards. This method, like the procedure described above in connec- tion with initialization, uses a key to release certain commands of the chip card operat- ing system. [0010] German laid-open print DE 199 02 722 A1 shows a cryptographic method for exchanging a secret initial value between a processing station and a chip card, which avoids transfer of the initial value in plaintext. [0011] The problem of the invention is to at least partly avoid the stated problems and to provide a way to initialize chip cards that is suitable in particular for initializa- tion performed by external partners, while offering few or no possibilities of attack. In particular the risk is to be reduced of an unauthorized person gaining access to the pro- tected initialization commands and/or of unauthorized loading of program codes into the chip card. To solve this problem, methods and apparatus having the features of the independent claims are provided according to the invention. The dependent claims define preferred embodiments of the invention Accordingly, the present invention provides a method for reading initialization data into a chip card involving the steps executed by the chip card of: receiving an encrypted authentication value, decrypting the encrypted authentication value to obtain at least one release key, checking whether the obtained release key matches a release key stored on the chip card, if the release keys match, receiving and writing the initialization data to a nonvolatile memory of the chip card, characterized in that the decryption of the encrypted authentication value further obtains at least one load key, and the initialization data are received by the chip card as encrypted initialization data and decrypted there with the load key. The present invention also provides a method for generating a record for initializing a chip card involving the steps of: generating an authentication value from which at least one release key is derivable, encrypting the authentication value with an authentication value key to obtain an encrypted authentication value, incorporating the encrypted authentication value into the record, and incorporating unencrypted or encrypted initialization data into the record, characterized in that a load key is generated, and the initialization data is encrypted with the load key and incorporated into the record as encrypted initialization data. The present invention further provides a method for initializing a chip card involving the steps of: generating a record by the above method in a manufacturer station, transferring the record to a processing station and reading the record into the chip card. The invention is based on the idea of neither making the release key accessible to the external partner in plaintext nor transferring it to the chip card in plaintext. Rather, the release key (optionally together with further information) is incorporated into an authentication value, and the authentication value is transferred exclusively in an encrypted state from the manufacturer to the external partner and from the external partner"s processing station to the chip card. The invention offers considerable advantages due to the fact that the release key is not transferred either to the external partner or to the chip card in plaintext and is also inaccessible to the external partner. This reliably avoids unauthorized access to the initialization commands of the chip card. The security of the total chip card system, which is also based on the safe secrecy of the internal structures and internal programming of the chip card, is thus increased, while external partners are simultaneously given the possibility to execute initialization process on their own premises. This increases the acceptance of the chip card system e.g. with GSM network operators, and broadens the possible application range of chip cards to areas of use in which external initialization of the chip card is required or desirable. European laid-open print EP-A 0 955 603 discloses a method by which a private key of the card manufacturer is sent to the initializing authority in encrypted form for reading in initialization data. In the chip card the decrypted private key is compared with the stored private key and if there is a match the initialization data is allowed [sic]. German patent application DE 35 23 237 A1 shows an apparatus for securing the transport of chip cards. This apparatus uses a release key for releasing certain commands of the chip card operating system. European patent application EP 0 973 135 A2 discloses an information processing and data storage comprising encrypting means for encrypting management information containing a key necessary to access a storage area. The information processing apparatus is applied for transmitting card issuing information to the chip cards. [0017] The order in which steps are listed in the claims is not intended to be restric- tive. Rather, embodiments of the invention are provided in which said steps are exe- cuted in a different order or parallel or quasi-parallel (interleaved). [0018] A "computer-readable data carrier" in the sense used here is intended to in- clude not only material data carriers, such as magnetic or optical disks or tapes, but also immaterial data carriers, such as voltage signals or optical signals with data in- formation modulated thereupon. [0019] In the wording of the present text, the term "initialization" is to refer pref- erably to the abovementioned transfer of programs and data to a relatively large num- ber of chip cards. In other embodiments of the invention, however, the term "initializa- tion" is to be understood more broadly, including not only initialization in the nar- rower sense but also post-initialization and/or personalization. In the present text, "ini- tialization data" refers not only to data in the narrower sense, but also to programs, program fragments and commands. [0020] According to the invention, a match is checked between a received release key and a release key stored on the chip card. The term "match" refers here preferably to identity of the two release keys. In other embodiments of the invention, however, another relation can be required between the two release keys. This other relation (e.g. that the two release keys are complementary) is referred to as a "match" in these em- bodiments. If the match has been detected, the initialization data are written to a mem- ory, preferably an EEPROM or a nonvolatile RAM. [0021] In preferred embodiments of the invention, it is provided that the initializa- tion data are transferred not in plaintext but as encrypted initialization data. The infor- mation required for decryption is contained in the authentication value or derivable therefrom. This information can be in particular a load key for decrypting the en- crypted initialization data. Encrypted transfer of the initialization data has the advan- tage that the chip card manufacturer"s trade secrets contained in said initialization data are safely guarded. Moreover, purposeful falsification of the initialization data is im- peded even further. [0022] In preferred embodiments of the invention, one or more initialization pa- rameters contained in the authentication value influence the loading of the initializa- tion data (e.g. by one of several practicable encryption methods being set). Alterna- tively or additionally it is provided in further embodiments of the invention that the initialization parameters influence the further run of initialization and/or the later func- tionality of the chip card. For example, the initialization parameters can make a selec- tion between several algorithms located in the mask-programmed ROM of the chip card for certain later functions of the chip card. This embodiment once again consid- erably increases the application range of the invention. [0023] To protect the authentication value from unauthorized manipulation, either the total authentication value or individual parts thereof (the release key and/or the load key and/or the initialization parameters) are secured by a cryptographic check sumin preferred embodiments of the invention. [0024] In preferred embodiments of the inventive methods as well as of the inven- tive chip card and inventive data carrier, these have features corresponding to the fea- tures described above or those defined in the dependent claims. [0025] Further features, properties and advantages of the invention will result from the following description of an embodiment and several alternative embodiments. In the schematic drawings, [0026] Fig. 1 shows an overview of the components and data communication paths involved in the overall method, [0027] Fig. 2 shows a data flowchart of the method for creating the record used for chip card initialization, and [0028] Fig. 3 shows a data flowchart of the method executed by the chip card dur- ing initialization. [0029] Fig. 1 shows schematically manufacturer station 10, processing station 12 and chip card 14. Manufacturer station 10 is disposed with the manufacturer of chip card 14, while processing station 12 and chip card 14 are located with an external part- ner of the chip card manufacturer. Between manufacturer station 10 and processing station 12 there is data transmission path 16, which can be realized for example as an electronic communication path via a telephone line or by the exchange of data carriers. Chip card 14 is connected to processing station 12 via wire connection 18. [0030] Components of chip card 14 are semiconductor chip 20 and contact bank 22 whose contacts are connected to wire connection 18. Semiconductor chip 20 has, in the way known in the art, interface circuit 24, microcontroller 26, read-write memory 28 (RAM = random access memory), nonvolatile memory 30 and mask-programmed read-only memory 32 (ROM). Nonvolatile memory 30 is designed in the present em- bodiment as an electrically erasable read-only memory (EEPROM). The stated func- tional blocks of semiconductor chip 20 are interconnected by bus 34. Interface circuit 24 is moreover connected to contact bank 22. [0031] The hitherto described embodiment of chip card 14 is known in the art. It is likewise known that read-only memory 32 has given release key ENK". Chip card 14 shown in Fig. 1 differs from the prior art, however, in that check sum key CSK" and authentication value key AVK" are also provided in mask-programmed read-only memory 32 of chip card 14. Authentication value key AVK" serves to decrypt an au- thentication value to be described in detail below, while check sum key CSK1 is pro- vided for checking the integrity of said authentication value. [0032] Manufacturer station 10 has access to initialization data IND, which nor- mally contain both program instructions and data values, to be transferred to chip card 14 in the initialization process. Further, manufacturer station 10 has one or more ini- tialization parameters INP and an identifier of external partner EXT. Finally, manufac- turer station 10 also has data values for release key ENK, check sum key CSK and au- thentication value key AVK. Values ENK, CSK and AVK are identical to values ENK", CSK" and AVK" stored in chip card 14. [0033] When compiling record DS required for initialization, manufacturer station 10 executes a method that is shown in Fig. 2 and will be described more precisely be- low. The result of this method is that record DS has encrypted initialization data EIND and encrypted authentication value EAV. Record DS is transferred to processing sta- tion 12 and buffered there. Upon initialization of chip card 14, processing station 12 transfers record DS to chip card 14. There the received data are evaluated by the method shown in Fig. 3, which is likewise described more precisely below. [0034] The method according to Fig. 2 is executed by manufacturer station 10. It starts out from given initialization data IND. From said data and the identifier of ex- ternal partner EXT, load key LDK is generated in step 40. In the embodiment de- scribed here, load key LDK is a random value that is newly generated for each pair of values IND, EXT. In alternative embodiments, load key LDK can also be calculated by another method in step 40. [0035] Load key LDK performs several functions. It firstly serves to encrypt ini- tialization data IND in step 42 to obtain encrypted initialization data EIND. Secondly, load key LDK is a component of authentication value AV. Further components of au- thentication value AV are one or more initialization parameters INP and release key ENK. [0036] In the embodiment described here, cryptographic check sum CCS is further calculated from the stated three values LDK, INP and ENK in step 44, using check sum key CSK as a key. The algorithm used for check sum calculation in the present embodiment is a MAC (message authentication code; see Chapter 4.6.4 of the above- cited book "Handbuch der Chipkarten") known in the art according to ISO 9797, while other calculation methods are provided in alternative embodiments. Cryptographic check sum CCS ensures the integrity of the data contained in authentication value AV. [0037] In the embodiment described here, authentication value AV is the concatena- tion of values LDK, INP, ENK and cryptographic check sum CCS, while in alternative embodiments other methods are used for determining authentication value AV and authentication value AV can contain further and/or different and/or fewer data. [0038] In further encryption step 46, authentication value AV is encrypted with au- thentication value key AVK to obtain encrypted authentication value EAV. The en- cryption method used in step 46 can be for example one of the DES or TRIPLE DES methods known in the art (DES = data encryption standard; see Chapter 4.6.1 of the above-cited book "Handbuch der Chipkarten"), preferably in the CBC mode {cipher block chaining) because this mode keeps the internal structures of authentication value AV hidden. Other encryption methods are provided for step 46 in alternative embodi- ments, however. [0039] In two final method steps 48 and 50, first encrypted authentication value EAV and then encrypted initialization data EIND are sent to processing station 12 to be buffered there and finally passed to chip card 14. Said encrypted data EAV and EIND together form record DS shown in Fig. 1, which can contain further components in alternative embodiments. [0040] Fig. 3 relates to the reception and processing of record DS (Fig. 1) by chip card 14. In step 60, chip card 14 first receives encrypted authentication value EAV, which originally comes from manufacturer station 10 and was transferred to process- ing station 12. Encrypted authentication value EAV is decrypted with authentication value key AVK" stored in read-only memory 32 of chip card 14 in step 62 to obtain authentication value AV with components LDK, INP, ENK and CCS. To simplify the present description it will be assumed that no falsification of record DS has taken place so that authentication value AV calculated in step 62 is identical with authentication value AV shown in Fig. 2. [0041] A check sum calculation is again effected (step 64), thereby determining cryptographic check sum CCS" from components LDK, INP and ENK using check sum key CSK" stored in chip card 14. Authentication value AV is rejected as faulty and the method aborted if a deviation of calculated check sum CCS1 from check sum CCS contained in decrypted authentication value AV is detected in step 66. [0042] If check sum calculation was successful, release key ENK contained in de- crypted authentication value AV is compared in further step 68 with release key ENK" stored in mask-programmed read-only memory 32 of chip card 14. If said comparison is also positive, the further loading of the initialization is released; otherwise the proc- ess is aborted. In alternative embodiments, steps 66 and 68 can be performed in a dif- ferent order. [0043] If the initialization process is continued, chip card 14 receives encrypted ini- tialization data EIND in step 70. Said data are decrypted in step 72, using load key LDK of calculated authentication value AV for decryption. The decryption method applied in step 72 can further depend on one or more of initialization parameters INP; for example, either DES or TRIPLE DES can be used depending on the parameter value. The decryption method in step 72 must of course match the method used for encryption in step 42 (Fig. 2). As the result of decryption step 72, chip card 14 obtains initialization data IND, which are written to nonvolatile memory 30 in step 74. [0044] To simplify the representation Fig. 3 shows steps 70 to 74 sequentially, while these steps are interleaved in the embodiment described here, in order to comply with the limited memory space conditions of chip card 14. [0045] After initialization data IND are loaded into nonvolatile memory 30, a fur- ther integrity check is effected in step 76 by means of a further cryptographic check sum in the way known in the art. If this integrity check is positive, initialization is ac- tivated in step 78. In the embodiment described here, one or more initialization pa- rameters INP are used for finally parameterizing the initialization. For example, it can be provided that initialization parameters INP make a selection among several algo- rithms located in read-only memory 32 for authentication in the GSM system. WE CLAIM : 1. A method for reading initialization data (IND) into a chip card (14) involving the steps executed by the chip card (14) of: - receiving an encrypted authentication value (EAV), - decrypting the encrypted authentication value (EAV) to obtain at least one release key (ENK), - checking whether the obtained release key (ENK) matches a release key (ENK") stored on the chip card (14), if the release keys (ENK, ENK") match, receiving and writing the initialization data (IND) to a nonvolatile memory (30) of the chip card (14), characterized in that the decryption of the encrypted authentication value (EAV) further obtains at least one load key (LDK), and the initialization data (IND) are received by the chip card (14) as encrypted initialization data (EIND) and decrypted there with the load key (LDK). 2. A method as claimed in claim 1, wherein the decryption of the encrypted authentication value (EAV) further obtains at least one initialization parameter (INP) such as described herein, which influences the further read-in and/or initialization process and/or the later functionality of the chip card (14). 3. A method as claimed in claim 1 or claim 2, wherein the release key (ENK) and/or the load key (LDK) and/or the at least one initialization parameter (INP) are secured by a cryptographic check sum (CCS), the cryptographic check sum (CCS) being derivable from the authentication value (AV). 4. A chip card having a microcontroller (26), a read-only memory (32) and a non- volatile memory (30) and set up to execute a method as claimed in any one of claims 1 to 4 under the control of the microcontroller (26). 5. A method for generating a record (DS) for initializing a chip card (14) involving the steps of: - generating an authentication value (AV) from which at least one release key (ENK) is derivable, - encrypting the authentication value (AV) with an authentication value key (AVK) to obtain an encrypted authentication value ((EAV), - incorporating the encrypted authentication value (EAV) into the record (DS), and - incorporating unencrypted or encrypted initialization data (IND, EIND) into the record (DS), characterized in that a load key (LDK) is generated, and the initialization data (IND) is encrypted with the load key (LDK) and incorporated into the record (DS) as encrypted initialization data (EIND). 6. A method as claimed in claim 5, wherein the authentication value (AV) is generated so that at least one initialization parameter (INP) is further derivable therefrom which influences the later read-in and/or initialization process and/or the , later functionality of the chip card (14). 7. A method as claimed in claim 5 or claim 6, wherein the release key (ENK) and/or the load key (LDK) and/or the initialization parameter (INP) are secured in the authentication value (AV) by a cryptographic check sum (CCS), the authentication value (AV) being generated so that the cryptographic check sum (CCS) is derivable therefrom. 8. A method for initializing a chip card (14) involving the steps of: - generating a record by the method as claimed any one of claims 5 to 7 in a manufacturer station (10), - transferring the record (DS) to a processing station (12), - reading the record (DS) into the chip card (14) by a method as claimed in any of claims 1 to 4. The method for reading initialization data (IND) into a chip card, the chip card receives an encrypted authentication value (EAV) and decrypts it to obtain at least one release key (ENK). The release key (ENK) is checked for a match with a release key (ENK") stored on the chip card (14). If there is a match, the initialization data (EIND, IND) are received and written to a nonvolatile memory of the chip card. A method for generating a record for initializing a chip card. A chip card and a computer-readable data carrier have corresponding features. The invention is provided in particular for initialization of chip cards by external partners of the chip card manufacturer, whereby as few possibilities of attack as possible are to be offered.

Full Text

A CHIP CARD AND A METHOD OF GENERATING
A RECORD FOR INITIALIZING A CHIP CARD
The present invention relates to a chip card and a method of generating a
record for initializing a chip card and in particular to the compilation and processing of
a record that is read into the chip card in an initialization step.
[0002] Chip cards are well known in many embodiments. They are used for exam-
ple for access control or in payment transactions and normally have a semiconductor
chip with a microcontroller and at least one memory. Besides the usual designs in
checkcard size or as small card modules (e.g. SIMs - subscriber identity modules in
mobile phones), chip cards are also produced in other designs (e.g. as key pendants or
rings). All these embodiments are to be referred to as "chip cards" in the present text.
[0003] During production of chip cards, initialization is the method step by which,
after completion and successful testing of the chip card hardware, those programs
and/or data are imported into the chip card that are identical for a relatively large num-
ber of chip cards. The subsequent step of loading personal, individual data is referred
to as personalization.
[0004] The separation of these two steps is effected for reasons of production engi-
neering to minimize the quantity of data to be transferred individually into individual
chip cards. In some cases of application, so-called post-initialization is inserted be-
tween the steps of initialization and personalization, by which additional programs
and/or data are written into a relatively small number of chip cards. An overview of
these production steps and their delimitation is found in Chapter 10.4 (pages 584 to
592) of the book "Handbuch der Chipkarten" by Wolfgang Rankl and Wolfgang Ef-
fing, 3rd edition 1999.
[0005] According to an at least internal prior art of the applicant, chip cards for the
GSM mobile phone system contain a 32-byte release key in a mask-programmed ROM
of the chip card. To start the initialization process a data value matching the release
key must be transferred to the chip card with a suitable command (e.g. VERIFY INI-
TIALIZATION KEY). The transferred value is compared with the release key stored
in the chip card ROM. In case of a match, access is released to an EEPROM of the
chip card and all chip card commands required for initialization.
[0006] Subsequent loading of initialization data into the chip card can be done ei-
ther openly or encrypted with a load key. Encrypted loading ensures that the privacy of
the encrypted initialization data is retained in case of unauthorized access.
[0007] However, this system still involves the problem that the release key must be
known to the authority performing initialization. It is increasingly required that not
only the chip card manufacturer itself but also external partners (e.g. mobile phone
network operators) initialize chip cards on their own. In this case there is a danger of
the release key being spied out during transfer to the external partner or when it is read
into the chip card, or of the external partner not keeping the release key strictly secret.
[0008] If the release key were made accessible to unauthorized persons a whole
chip card product line might possibly be compromised, because the release key per-
mits access to diverse basic chip card functions which can in turn be used for spying
out the chip card"s hardware and software. For example, if an unauthorized third per-
son knows the release key he can load his own program code into the chip card and
thus spy out the code already located in the mask-programmed ROM. :
[0009] German laid-open print DE 196 33 466 A1 discloses a method for post-
initialization of chip cards. This method, like the procedure described above in connec-
tion with initialization, uses a key to release certain commands of the chip card operat-
ing system.
[0010] German laid-open print DE 199 02 722 A1 shows a cryptographic method
for exchanging a secret initial value between a processing station and a chip card,
which avoids transfer of the initial value in plaintext.
[0011] The problem of the invention is to at least partly avoid the stated problems
and to provide a way to initialize chip cards that is suitable in particular for initializa-
tion performed by external partners, while offering few or no possibilities of attack. In
particular the risk is to be reduced of an unauthorized person gaining access to the pro-
tected initialization commands and/or of unauthorized loading of program codes into
the chip card.
To solve this problem, methods and apparatus having the features of the
independent claims are provided according to the invention. The dependent claims
define preferred embodiments of the invention
Accordingly, the present invention provides a method for reading initialization
data into a chip card involving the steps executed by the chip card of: receiving an
encrypted authentication value, decrypting the encrypted authentication value to obtain
at least one release key, checking whether the obtained release key matches a release
key stored on the chip card, if the release keys match, receiving and writing the
initialization data to a nonvolatile memory of the chip card, characterized in that the
decryption of the encrypted authentication value further obtains at least one load key,
and the initialization data are received by the chip card as encrypted initialization data
and decrypted there with the load key.
The present invention also provides a method for generating a record for
initializing a chip card involving the steps of: generating an authentication value from
which at least one release key is derivable, encrypting the authentication value with an
authentication value key to obtain an encrypted authentication value, incorporating the
encrypted authentication value into the record, and incorporating unencrypted or
encrypted initialization data into the record, characterized in that a load key is generated,
and the initialization data is encrypted with the load key and incorporated into the record
as encrypted initialization data.
The present invention further provides a method for initializing a chip card involving
the steps of: generating a record by the above method in a manufacturer station,
transferring the record to a processing station and reading the record into the chip card.
The invention is based on the idea of neither making the release key accessible
to the external partner in plaintext nor transferring it to the chip card in plaintext.
Rather, the release key (optionally together with further information) is incorporated
into an authentication value, and the authentication value is transferred exclusively in
an encrypted state from the manufacturer to the external partner and from the
external partner"s processing station to the chip card.
The invention offers considerable advantages due to the fact that the release
key is not transferred either to the external partner or to the chip card in plaintext and
is also inaccessible to the external partner. This reliably avoids unauthorized access
to the initialization commands of the chip card.
The security of the total chip card system, which is also based on the safe
secrecy of the internal structures and internal programming of the chip card, is thus
increased, while external partners are simultaneously given the possibility to execute
initialization process on their own premises. This increases the acceptance of the chip
card system e.g. with GSM network operators, and broadens the possible application
range of chip cards to areas of use in which external initialization of the chip card is
required or desirable.
European laid-open print EP-A 0 955 603 discloses a method by which a
private key of the card manufacturer is sent to the initializing authority in encrypted
form for reading in initialization data. In the chip card the decrypted private key is
compared with the stored private key and if there is a match the initialization data is
allowed [sic].
German patent application DE 35 23 237 A1 shows an apparatus for securing
the transport of chip cards. This apparatus uses a release key for releasing certain
commands of the chip card operating system.
European patent application EP 0 973 135 A2 discloses an information
processing and data storage comprising encrypting means for encrypting
management information containing a key necessary to access a storage area. The
information processing apparatus is applied for transmitting card issuing information to
the chip cards.
[0017] The order in which steps are listed in the claims is not intended to be restric-
tive. Rather, embodiments of the invention are provided in which said steps are exe-
cuted in a different order or parallel or quasi-parallel (interleaved).
[0018] A "computer-readable data carrier" in the sense used here is intended to in-
clude not only material data carriers, such as magnetic or optical disks or tapes, but
also immaterial data carriers, such as voltage signals or optical signals with data in-
formation modulated thereupon.
[0019] In the wording of the present text, the term "initialization" is to refer pref-
erably to the abovementioned transfer of programs and data to a relatively large num-
ber of chip cards. In other embodiments of the invention, however, the term "initializa-
tion" is to be understood more broadly, including not only initialization in the nar-
rower sense but also post-initialization and/or personalization. In the present text, "ini-
tialization data" refers not only to data in the narrower sense, but also to programs,
program fragments and commands.
[0020] According to the invention, a match is checked between a received release
key and a release key stored on the chip card. The term "match" refers here preferably
to identity of the two release keys. In other embodiments of the invention, however,
another relation can be required between the two release keys. This other relation (e.g.
that the two release keys are complementary) is referred to as a "match" in these em-
bodiments. If the match has been detected, the initialization data are written to a mem-
ory, preferably an EEPROM or a nonvolatile RAM.
[0021] In preferred embodiments of the invention, it is provided that the initializa-
tion data are transferred not in plaintext but as encrypted initialization data. The infor-
mation required for decryption is contained in the authentication value or derivable
therefrom. This information can be in particular a load key for decrypting the en-
crypted initialization data. Encrypted transfer of the initialization data has the advan-
tage that the chip card manufacturer"s trade secrets contained in said initialization data
are safely guarded. Moreover, purposeful falsification of the initialization data is im-
peded even further.
[0022] In preferred embodiments of the invention, one or more initialization pa-
rameters contained in the authentication value influence the loading of the initializa-
tion data (e.g. by one of several practicable encryption methods being set). Alterna-
tively or additionally it is provided in further embodiments of the invention that the
initialization parameters influence the further run of initialization and/or the later func-
tionality of the chip card. For example, the initialization parameters can make a selec-
tion between several algorithms located in the mask-programmed ROM of the chip
card for certain later functions of the chip card. This embodiment once again consid-
erably increases the application range of the invention.
[0023] To protect the authentication value from unauthorized manipulation, either
the total authentication value or individual parts thereof (the release key and/or the
load key and/or the initialization parameters) are secured by a cryptographic check
sumin preferred embodiments of the invention.
[0024] In preferred embodiments of the inventive methods as well as of the inven-
tive chip card and inventive data carrier, these have features corresponding to the fea-
tures described above or those defined in the dependent claims.
[0025] Further features, properties and advantages of the invention will result from
the following description of an embodiment and several alternative embodiments. In
the schematic drawings,
[0026] Fig. 1 shows an overview of the components and data communication paths
involved in the overall method,
[0027] Fig. 2 shows a data flowchart of the method for creating the record used for
chip card initialization, and
[0028] Fig. 3 shows a data flowchart of the method executed by the chip card dur-
ing initialization.
[0029] Fig. 1 shows schematically manufacturer station 10, processing station 12
and chip card 14. Manufacturer station 10 is disposed with the manufacturer of chip
card 14, while processing station 12 and chip card 14 are located with an external part-
ner of the chip card manufacturer. Between manufacturer station 10 and processing
station 12 there is data transmission path 16, which can be realized for example as an
electronic communication path via a telephone line or by the exchange of data carriers.
Chip card 14 is connected to processing station 12 via wire connection 18.
[0030] Components of chip card 14 are semiconductor chip 20 and contact bank 22
whose contacts are connected to wire connection 18. Semiconductor chip 20 has, in
the way known in the art, interface circuit 24, microcontroller 26, read-write memory
28 (RAM = random access memory), nonvolatile memory 30 and mask-programmed
read-only memory 32 (ROM). Nonvolatile memory 30 is designed in the present em-
bodiment as an electrically erasable read-only memory (EEPROM). The stated func-
tional blocks of semiconductor chip 20 are interconnected by bus 34. Interface circuit
24 is moreover connected to contact bank 22.
[0031] The hitherto described embodiment of chip card 14 is known in the art. It is
likewise known that read-only memory 32 has given release key ENK". Chip card 14
shown in Fig. 1 differs from the prior art, however, in that check sum key CSK" and
authentication value key AVK" are also provided in mask-programmed read-only
memory 32 of chip card 14. Authentication value key AVK" serves to decrypt an au-
thentication value to be described in detail below, while check sum key CSK1 is pro-
vided for checking the integrity of said authentication value.
[0032] Manufacturer station 10 has access to initialization data IND, which nor-
mally contain both program instructions and data values, to be transferred to chip card
14 in the initialization process. Further, manufacturer station 10 has one or more ini-
tialization parameters INP and an identifier of external partner EXT. Finally, manufac-
turer station 10 also has data values for release key ENK, check sum key CSK and au-
thentication value key AVK. Values ENK, CSK and AVK are identical to values
ENK", CSK" and AVK" stored in chip card 14.
[0033] When compiling record DS required for initialization, manufacturer station
10 executes a method that is shown in Fig. 2 and will be described more precisely be-
low. The result of this method is that record DS has encrypted initialization data EIND
and encrypted authentication value EAV. Record DS is transferred to processing sta-
tion 12 and buffered there. Upon initialization of chip card 14, processing station 12
transfers record DS to chip card 14. There the received data are evaluated by the
method shown in Fig. 3, which is likewise described more precisely below.
[0034] The method according to Fig. 2 is executed by manufacturer station 10. It
starts out from given initialization data IND. From said data and the identifier of ex-
ternal partner EXT, load key LDK is generated in step 40. In the embodiment de-
scribed here, load key LDK is a random value that is newly generated for each pair of
values IND, EXT. In alternative embodiments, load key LDK can also be calculated
by another method in step 40.
[0035] Load key LDK performs several functions. It firstly serves to encrypt ini-
tialization data IND in step 42 to obtain encrypted initialization data EIND. Secondly,
load key LDK is a component of authentication value AV. Further components of au-
thentication value AV are one or more initialization parameters INP and release key
ENK.
[0036] In the embodiment described here, cryptographic check sum CCS is further
calculated from the stated three values LDK, INP and ENK in step 44, using check
sum key CSK as a key. The algorithm used for check sum calculation in the present
embodiment is a MAC (message authentication code; see Chapter 4.6.4 of the above-
cited book "Handbuch der Chipkarten") known in the art according to ISO 9797, while
other calculation methods are provided in alternative embodiments. Cryptographic
check sum CCS ensures the integrity of the data contained in authentication value AV.
[0037] In the embodiment described here, authentication value AV is the concatena-
tion of values LDK, INP, ENK and cryptographic check sum CCS, while in alternative
embodiments other methods are used for determining authentication value AV and
authentication value AV can contain further and/or different and/or fewer data.
[0038] In further encryption step 46, authentication value AV is encrypted with au-
thentication value key AVK to obtain encrypted authentication value EAV. The en-
cryption method used in step 46 can be for example one of the DES or TRIPLE DES
methods known in the art (DES = data encryption standard; see Chapter 4.6.1 of the
above-cited book "Handbuch der Chipkarten"), preferably in the CBC mode {cipher
block chaining) because this mode keeps the internal structures of authentication value
AV hidden. Other encryption methods are provided for step 46 in alternative embodi-
ments, however.
[0039] In two final method steps 48 and 50, first encrypted authentication value
EAV and then encrypted initialization data EIND are sent to processing station 12 to
be buffered there and finally passed to chip card 14. Said encrypted data EAV and
EIND together form record DS shown in Fig. 1, which can contain further components
in alternative embodiments.
[0040] Fig. 3 relates to the reception and processing of record DS (Fig. 1) by chip
card 14. In step 60, chip card 14 first receives encrypted authentication value EAV,
which originally comes from manufacturer station 10 and was transferred to process-
ing station 12. Encrypted authentication value EAV is decrypted with authentication
value key AVK" stored in read-only memory 32 of chip card 14 in step 62 to obtain
authentication value AV with components LDK, INP, ENK and CCS. To simplify the
present description it will be assumed that no falsification of record DS has taken place
so that authentication value AV calculated in step 62 is identical with authentication
value AV shown in Fig. 2.
[0041] A check sum calculation is again effected (step 64), thereby determining
cryptographic check sum CCS" from components LDK, INP and ENK using check
sum key CSK" stored in chip card 14. Authentication value AV is rejected as faulty
and the method aborted if a deviation of calculated check sum CCS1 from check sum
CCS contained in decrypted authentication value AV is detected in step 66.
[0042] If check sum calculation was successful, release key ENK contained in de-
crypted authentication value AV is compared in further step 68 with release key ENK"
stored in mask-programmed read-only memory 32 of chip card 14. If said comparison
is also positive, the further loading of the initialization is released; otherwise the proc-
ess is aborted. In alternative embodiments, steps 66 and 68 can be performed in a dif-
ferent order.
[0043] If the initialization process is continued, chip card 14 receives encrypted ini-
tialization data EIND in step 70. Said data are decrypted in step 72, using load key
LDK of calculated authentication value AV for decryption. The decryption method
applied in step 72 can further depend on one or more of initialization parameters INP;
for example, either DES or TRIPLE DES can be used depending on the parameter
value. The decryption method in step 72 must of course match the method used for
encryption in step 42 (Fig. 2). As the result of decryption step 72, chip card 14 obtains
initialization data IND, which are written to nonvolatile memory 30 in step 74.
[0044] To simplify the representation Fig. 3 shows steps 70 to 74 sequentially,
while these steps are interleaved in the embodiment described here, in order to comply
with the limited memory space conditions of chip card 14.
[0045] After initialization data IND are loaded into nonvolatile memory 30, a fur-
ther integrity check is effected in step 76 by means of a further cryptographic check
sum in the way known in the art. If this integrity check is positive, initialization is ac-
tivated in step 78. In the embodiment described here, one or more initialization pa-
rameters INP are used for finally parameterizing the initialization. For example, it can
be provided that initialization parameters INP make a selection among several algo-
rithms located in read-only memory 32 for authentication in the GSM system.
WE CLAIM :
1. A method for reading initialization data (IND) into a chip card (14) involving
the steps executed by the chip card (14) of:
- receiving an encrypted authentication value (EAV),
- decrypting the encrypted authentication value (EAV) to obtain at least one
release key (ENK),
- checking whether the obtained release key (ENK) matches a release key
(ENK") stored on the chip card (14),
if the release keys (ENK, ENK") match, receiving and writing the
initialization data (IND) to a nonvolatile memory (30) of the chip card (14),
characterized in that the decryption of the encrypted authentication value
(EAV) further obtains at least one load key (LDK), and the initialization data (IND)
are received by the chip card (14) as encrypted initialization data (EIND) and
decrypted there with the load key (LDK).
2. A method as claimed in claim 1, wherein the decryption of the encrypted
authentication value (EAV) further obtains at least one initialization parameter (INP)
such as described herein, which influences the further read-in and/or initialization
process and/or the later functionality of the chip card (14).
3. A method as claimed in claim 1 or claim 2, wherein the release key (ENK)
and/or the load key (LDK) and/or the at least one initialization parameter (INP) are
secured by a cryptographic check sum (CCS), the cryptographic check sum (CCS)
being derivable from the authentication value (AV).
4. A chip card having a microcontroller (26), a read-only memory (32) and a non-
volatile memory (30) and set up to execute a method as claimed in any one of claims 1
to 4 under the control of the microcontroller (26).
5. A method for generating a record (DS) for initializing a chip card (14)
involving the steps of:
- generating an authentication value (AV) from which at least one release
key (ENK) is derivable,
- encrypting the authentication value (AV) with an authentication value key
(AVK) to obtain an encrypted authentication value ((EAV),
- incorporating the encrypted authentication value (EAV) into the record
(DS), and
- incorporating unencrypted or encrypted initialization data (IND, EIND) into
the record (DS),
characterized in that a load key (LDK) is generated, and the initialization
data (IND) is encrypted with the load key (LDK) and incorporated into the record
(DS) as encrypted initialization data (EIND).
6. A method as claimed in claim 5, wherein the authentication value (AV) is
generated so that at least one initialization parameter (INP) is further derivable
therefrom which influences the later read-in and/or initialization process and/or the
, later functionality of the chip card (14).
7. A method as claimed in claim 5 or claim 6, wherein the release key (ENK)
and/or the load key (LDK) and/or the initialization parameter (INP) are secured in
the authentication value (AV) by a cryptographic check sum (CCS), the
authentication value (AV) being generated so that the cryptographic check sum
(CCS) is derivable therefrom.
8. A method for initializing a chip card (14) involving the steps of:
- generating a record by the method as claimed any one of claims 5 to 7 in a
manufacturer station (10),
- transferring the record (DS) to a processing station (12),
- reading the record (DS) into the chip card (14) by a method as claimed in
any of claims 1 to 4.
The method for reading initialization data (IND) into a chip card, the
chip card receives an encrypted authentication value (EAV) and decrypts it to
obtain at least one release key (ENK). The release key (ENK) is checked for
a match with a release key (ENK") stored on the chip card (14). If there is a
match, the initialization data (EIND, IND) are received and written to a
nonvolatile memory of the chip card. A method for generating a record for
initializing a chip card. A chip card and a computer-readable data carrier have
corresponding features. The invention is provided in particular for initialization
of chip cards by external partners of the chip card manufacturer, whereby as
few possibilities of attack as possible are to be offered.

Documents:

240-kolnp-2004-granted-abstract.pdf

240-kolnp-2004-granted-assignment.pdf

240-kolnp-2004-granted-claims.pdf

240-kolnp-2004-granted-correspondence.pdf

240-kolnp-2004-granted-description (complete).pdf

240-kolnp-2004-granted-drawings.pdf

240-kolnp-2004-granted-form 1.pdf

240-kolnp-2004-granted-form 3.pdf

240-kolnp-2004-granted-form 5.pdf

240-kolnp-2004-granted-letter patent.pdf

240-kolnp-2004-granted-pa.pdf

240-kolnp-2004-granted-reply to examination report.pdf

240-kolnp-2004-granted-specification.pdf

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Patent Number

218572

Indian Patent Application Number

00240/KOLNP/2004

PG Journal Number

14/2008

Publication Date

04-Apr-2008

Grant Date

02-Apr-2008

Date of Filing

20-Feb-2004

Name of Patentee

GIESECKE & DEVRIENT GMBH

Applicant Address

PRINZREGENTENSTRASSE 159, 81677 MUNCHEN GERMANY

Inventors:

#	Inventor's Name	Inventor's Address
1	HARTEL KARL EGLOF	REUTTERSTRASSE 74, 80689 MUNCHEN GERMANY
2	VATER HARALD	AN DEN SCHULGARTEN 23, 35389 GIESSEN GERMANY.

PCT International Classification Number

G07F7/10

PCT International Application Number

PCT/EP02/09561

PCT International Filing date

2002-08-27

PCT Conventions:

#	PCT Application Number	Date of Convention	Priority Country
1	101 42 351.9	2001-08-30	Germany