new file mode 100644
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+Qemu CCID Device Documentation.
+
+Contents
+1. USB CCID device
+2. Building
+3. Using ccid-card-emulated with hardware
+4. Using ccid-card-emulated with certificates
+5. Using ccid-card-passthru with client side hardware
+6. Using ccid-card-passthru with client side certificates
+7. Passthrough protocol scenario
+8. libcaccard
+
+1. USB CCID device
+
+The USB CCID device is a USB device implementing the CCID specification, which
+lets one connect smart card readers that implement the same spec. For more
+information see the specification:
+
+ Universal Serial Bus
+ Device Class: Smart Card
+ CCID
+ Specification for
+ Integrated Circuit(s) Cards Interface Devices
+ Revision 1.1
+ April 22rd, 2005
+
+Smartcard are used for authentication, single sign on, decryption in
+public/private schemes and digital signatures. A smartcard reader on the client
+cannot be used on a guest with simple usb passthrough since it will then not be
+available on the client, possibly locking the computer when it is "removed". On
+the other hand this device can let you use the smartcard on both the client and
+the guest machine. It is also possible to have a completely virtual smart card
+reader and smart card (i.e. not backed by a physical device) using this device.
+
+2. Building
+
+The cryptographic functions and access to the physical card is done via NSS.
+
+Installing NSS:
+
+In redhat/fedora:
+ yum install nss-devel
+In ubuntu/debian:
+ apt-get install libnss3-dev
+ (not tested on ubuntu)
+
+Configuring and building:
+ ./configure --enable-smartcard && make
+
+3. Using ccid-card-emulated with hardware
+
+Assuming you have a working smartcard on the host with the current
+user, using NSS, qemu acts as another NSS client using ccid-card-emulated:
+
+ qemu -usb -device usb-ccid -device ccid-card-emualated
+
+4. Using ccid-card-emulated with certificates
+
+You must create the certificates. This is a one time process. We use NSS
+certificates:
+
+ certutil -d /etc/pki/nssdb -x -t "CT,CT,CT" -S -s "CN=cert1" -n cert1
+
+Note: you must have exactly three certificates.
+
+Assuming the current user can access the certificates (use certutil -L to
+verify), you can use the emulated card type with the certificates backend:
+
+ qemu -usb -device usb-ccid -device ccid-card-emulated,backend=certificates,cert1=cert1,cert2=cert2,cert3=cert3
+
+5. Using ccid-card-passthru with client side hardware
+
+on the host specify the ccid-card-passthru device with a suitable chardev:
+
+ qemu -chardev socket,server,host=0.0.0.0,port=2001,id=ccid,nowait -usb -device usb-ccid -device ccid-card-passthru,chardev=ccid
+
+on the client run vscclient, built when you built the libcaccard library:
+ libcaccard/vscclient <qemu-host> 2001
+
+6. Using ccid-card-passthru with client side certificates
+
+Run qemu as per #5, and run vscclient as follows:
+(Note: vscclient command line interface is in a state of change)
+
+ libcaccard/vscclient -e "db=\"/etc/pki/nssdb\" use_hw=no soft=(,Test,CAC,,cert1,cert2,cert3)" <qemu-host> 2001
+
+7. Passthrough protocol scenario
+
+This is a typical interchange of messages when using the passthru card device.
+usb-ccid is a usb device. It defaults to an unattached usb device on startup.
+usb-ccid expects a chardev and expects the protocol defined in
+cac_card/vscard_common.h to be passed over that.
+
+A typical interchange is:
+
+client event | vscclient | passthru | usb-ccid | guest event
+----------------------------------------------------------------------------------------------
+ | VSC_Init | | |
+ | VSC_ReaderAdd | | attach |
+ | | | | sees new usb device.
+card inserted | | | |
+ | VSC_ATR | | |
+ | | | | guest operation, APDU transfer via CCID
+ | | VSC_APDU | |
+ | VSC_APDU | | |
+client<->physical | | | |
+card APDU exchange| | | |
+ [APDU<->APDU repeats several times]
+card removed | | | |
+ | VSC_CardRemove | | |
+kill/quit | | | |
+ vscclient | | | |
+ | VSC_ReaderRemove | | detach |
+ | | | | usb device removed.
+
+
+8. libcaccard
+
+ccid-card-passthru and vscclient use libcaccard as the card emulator.
+libcaccard implements a completely virtual CAC (DoD standard for smart cards)
+compliant card and uses NSS to actually retrive certificates and do any
+encryption using the backend (real reader + card or file backed certificates).
+
+For documentation of cac_card see README in libcaccard subdirectory.
+
deleted file mode 100644
@@ -1,483 +0,0 @@
-This file documents the CAC (Common Access Card) library in the libcacard
-subdirectory.
-
-Virtual Smart Card Emulator
-
-This emulator is designed to provide emulation of actual smart cards to a
-virtual card reader running in a guest virtual machine. The emulated smart
-cards can be representations of real smart cards, where the necessary functions
-such as signing, card removal/insertion, etc. are mapped to real, physical
-cards which are shared with the client machine the emulator is running on, or
-the cards could be pure software constructs.
-
-The emulator is structured to allow multiple replacable or additional pieces,
-so it can be easily modified for future requirements. The primary envisioned
-modifications are:
-
-1) The socket connection to the virtual card reader (presumably a CCID reader,
-but other ISO-7816 compatible readers could be used). The code that handles
-this is in vscclient.c.
-
-2) The virtual card low level emulation. This is currently supplied by using
-NSS. This emulation could be replaced by implementations based on other
-security libraries, including but not limitted to openssl+pkcs#11 library,
-raw pkcs#11, Microsoft CAPI, direct opensc calls, etc. The code that handles
-this is in vcard_emul_nss.c.
-
-3) Emulation for new types of cards. The current implementation emulates the
-original DoD CAC standard with separate pki containers. This emulator lives in
-cac.c. More than one card type emulator could be included. Other cards could
-be emulated as well, including PIV, newer versions of CAC, PKCS #15, etc.
-
---------------------
-Replacing the Socket Based Virtual Reader Interface.
-
-The current implementation contains a replacable module vscclient.c. The
-current vscclient.c implements a sockets interface to the virtual ccid reader
-on the guest. CCID commands that are pertinent to emulation are passed
-across the socket, and their responses are passed back along that same socket.
-The protocol that vscclient uses is defined in vscard_common.h and connects
-to a qemu ccid usb device. Since this socket runs as a client, vscclient.c
-implements a program with a main entry. It also handles argument parsing for
-the emulator.
-
-An application that wants to use the virtual reader can replace vscclient.c
-with it's own implementation that connects to it's own CCID reader. The calls
-that the CCID reader can call are:
-
- VReaderList * vreader_get_reader_list();
-
- This function returns a list of virtual readers. These readers may map to
- physical devices, or simulated devices depending on vcard the back end. Each
- reader in the list should represent a reader to the virtual machine. Virtual
- USB address mapping is left to the CCID reader front end. This call can be
- made any time to get an updated list. The returned list is a copy of the
- internal list that can be referenced by the caller without locking. This copy
- must be freed by the caller with vreader_list_delete when it is no longer
- needed.
-
- VReaderListEntry *vreader_list_get_first(VReaderList *);
-
- This function gets the first entry on the reader list. Along with
- vreader_list_get_next(), vreader_list_get_first() can be used to walk the
- reader list returned from vreader_get_reader_list(). VReaderListEntries are
- part of the list themselves and do not need to be freed separately from the
- list. If there are no entries on the list, it will return NULL.
-
- VReaderListEntry *vreader_list_get_next(VReaderListEntry *);
-
- This function gets the next entry in the list. If there are no more entries
- it will return NULL.
-
- VReader * vreader_list_get_reader(VReaderListEntry *)
-
- This function returns the reader stored in the reader List entry. Caller gets
- a new reference to a reader. The caller must free it's reference when it is
- finished with vreader_free().
-
- void vreader_free(VReader *reader);
-
- This function frees a reference to a reader. Reader's are reference counted
- and are automatically deleted when the last reference is freed.
-
- void vreader_list_delete(VReaderList *list);
-
- This function frees the list, all the elements on the list, and all the
- reader references held by the list.
-
- VReaderStatus vreader_power_on(VReader *reader, char *atr, int *len);
-
- This functions simulates a card power on. Virtual cards do not care about
- the actual voltage and other physical parameters, but it does care that the
- card is actually on or off. Cycling the card causes the card to reset. If
- the caller provides enough space, vreader_power_on will return the ATR of
- the virtual card. The amount of space provided in atr should be indicated
- in *len. The function modifies *len to be the actual length of of the
- returned ATR.
-
- VReaderStatus vreader_power_off(VReader *reader);
-
- This function simulates a power off of a virtual card.
-
- VReaderStatus vreader_xfer_bytes(VReader *reader, unsigne char *send_buf,
- int send_buf_len,
- unsigned char *receive_buf,
- int receive_buf_len);
-
- This functions send a raw apdu to a card and returns the card's response.
- The CCID front end should return the response back. Most of the emulation
- is driven from these APDUs.
-
- VReaderStatus vreader_card_is_present(VReader *reader);
-
- This function returns whether or not the reader has a card inserted. The
- vreader_power_on, vreader_power_off, and vreader_xfer_bytes will return
- VREADER_NO_CARD.
-
- const char *vreader_get_name(VReader *reader);
-
- This function returns the name of the reader. The name comes from the card
- emulator level and is usually related to the name of the physical reader.
-
- VReaderID vreader_get_id(VReader *reader);
-
- This function returns the id of a reader. All readers start out with an id
- of -1. The application can set the id with vreader_set_id.
-
- VReaderStatus vreader_get_id(VReader *reader, VReaderID id);
-
- This function sets the reader id. The application is responsible for making
- sure that the id is unique for all readers it is actively using.
-
- VReader *vreader_find_reader_by_id(VReaderID id);
-
- This function returns the reader which matches the id. If two readers match,
- only one is returned. The function returns NULL if the id is -1.
-
- Event *vevent_wait_next_vevent();
-
- This function blocks waiting for reader and card insertion events. There
- will be one event for each card insertion, each card removal, each reader
- insertion and each reader removal. At start up, events are created for all
- the initial readers found, as well as all the cards that are inserted.
-
- Event *vevent_get_next_vevent();
-
- This function returns a pending event if it exists, otherwise it returns
- NULL. It does not block.
-
-----------------
-Card Type Emulator: Adding a New Virtual Card Type
-
-The ISO 7816 card spec describes 2 types of cards:
- 1) File system cards, where the smartcard is managed by reading and writing
-data to files in a file system. There is currently only boiler plate
-implemented for file system cards.
- 2) VM cards, where the card has loadable applets which perform the card
-functions. The current implementation supports VM cards.
-
-In the case of VM cards, the difference between various types of cards is
-really what applets have been installed in that card. This structure is
-mirrored in card type emulators. The 7816 emulator already handles the basic
-ISO 7186 commands. Card type emulators simply need to add the virtual applets
-which emulate the real card applets. Card type emulators have exactly one
-public entry point:
-
- VCARDStatus xxx_card_init(VCard *card, const char *flags,
- const unsigned char *cert[],
- int cert_len[],
- VCardKey *key[],
- int cert_count);
-
- The parameters for this are:
- card - the virtual card structure which will prepresent this card.
- flags - option flags that may be specific to this card type.
- cert - array of binary certificates.
- cert_len - array of lengths of each of the certificates specified in cert.
- key - array of opaque key structures representing the private keys on
- the card.
- cert_count - number of entries in cert, cert_len, and key arrays.
-
- Any cert, cert_len, or key with the same index are matching sets. That is
- cert[0] is cert_len[0] long and has the corresponsing private key of key[0].
-
-The card type emulator is expected to own the VCardKeys, but it should copy
-any raw cert data it wants to save. It can create new applets and add them to
-the card using the following functions:
-
- VCardApplet *vcard_new_applet(VCardProcessAPDU apdu_func,
- VCardResetApplet reset_func,
- const unsigned char *aid,
- int aid_len);
-
- This function creates a new applet. Applet structures store the following
- information:
- 1) the AID of the applet (set by aid and aid_len).
- 2) a function to handle APDUs for this applet. (set by apdu_func, more on
- this below).
- 3) a function to reset the applet state when the applet is selected.
- (set by reset_func, more on this below).
- 3) applet private data, a data pointer used by the card type emulator to
- store any data or state it needs to complete requests. (set by a
- separate call).
- 4) applet private data free, a function used to free the applet private
- data when the applet itself is destroyed.
- The created applet can be added to the card with vcard_add_applet below.
-
- void vcard_set_applet_private(VCardApplet *applet,
- VCardAppletPrivate *private,
- VCardAppletPrivateFree private_free);
- This function sets the private data and the corresponding free function.
- VCardAppletPrivate is an opaque data structure to the rest of the emulator.
- The card type emulator can define it any way it wants by defining
- struct VCardAppletPrivateStruct {};. If there is already a private data
- structure on the applet, the old one is freed before the new one is set up.
- passing two NULL clear any existing private data.
-
- VCardStatus vcard_add_applet(VCard *card, VCardApplet *applet);
-
- Add an applet onto the list of applets attached to the card. Once an applet
- has been added, it can be selected by it's aid, and then commands will be
- routed to it VCardProcessAPDU function. This function adopts the applet the
- passed int applet. Note: 2 applets with the same AID should not be added to
- the same card. It's permissible to add more than one applet. Multiple applets
- may have the same VCardPRocessAPDU entry point.
-
-The certs and keys should be attached to private data associated with one or
-more appropriate applets for that card. Control will come to the card type
-emulators once one of its applets are selected through the VCardProcessAPDU
-function it specified when it created the applet.
-
-The signature of VCardResetApplet is:
- VCardStatus (*VCardResetApplet) (VCard *card, int channel);
- This function will reset the any internal applet state that needs to be
- cleared after a select applet call. It should return VCARD_DONE;
-
-The signature of VCardProcessAPDU is:
- VCardStatus (*VCardProcessAPDU)(VCard *card, VCardAPDU *apdu,
- VCardResponse **response);
- This function examines the APDU and determines whether it should process
- the apdu directly, reject the apdu as invalid, or pass the apdu on to
- the basic 7816 emulator for processing.
- If the 7816 emulator should process the apdu, then the VCardProcessAPDU
- should return VCARD_NEXT.
- If there is an error, then VCardProcessAPDU should return an error
- response using vcard_make_response and the appropriate 7816 error code
- (see card_7816t.h) or vcard_make_response with a card type specific error
- code. It should then return VCARD_DONE.
- If the apdu can be processed correctly, VCardProcessAPDU should do so,
- set the response value appropriately for that APDU, and return VCARD_DONE.
- VCardProcessAPDU should always set the response if it returns VCARD_DONE.
- It should always either return VCARD_DONE or VCARD_NEXT.
-
-Parsing the APDU --
-
-Prior to processing calling the card type emulator's VCardProcessAPDU function, the emulator has already decoded the APDU header and set several fields:
-
- apdu->a_data - The raw apdu data bytes.
- apdu->a_len - The len of the raw apdu data.
- apdu->a_body - The start of any post header parameter data.
- apdu->a_Lc - The parameter length value.
- apdu->a_Le - The expected length of any returned data.
- apdu->a_cla - The raw apdu class.
- apdu->a_channel - The channel (decoded from the class).
- apdu->a_secure_messaging_type - The decoded secure messagin type
- (from class).
- apdu->a_type - The decode class type.
- apdu->a_gen_type - the generic class type (7816, PROPRIETARY, RFU, PTS).
- apdu->a_ins - The instruction byte.
- apdu->a_p1 - Parameter 1.
- apdu->a_p2 - Parameter 2.
-
-Creating a Response --
-
-The expected result of any APDU call is a response. The card type emulator must
-set *response with an appropriate VCardResponse value if it returns VCARD_DONE.
-Reponses could be as simple as returning a 2 byte status word response, to as
-complex as returning a block of data along with a 2 byte response. Which is
-returned will depend on the semantics of the APDU. The following functions will
-create card responses.
-
- VCardResponse *vcard_make_response(VCard7816Status status);
-
- This is the most basic function to get a response. This function will
- return a response the consists soley one 2 byte status code. If that status
- code is defined in card_7816t.h, then this function is guarrenteed to
- return a response with that status. If a cart type specific status code
- is passed and vcard_make_response fails to allocate the appropriate memory
- for that response, then vcard_make_response will return a VCardResponse
- of VCARD7816_STATUS_EXC_ERROR_MEMORY. In any case, this function is
- guarrenteed to return a valid VCardResponse.
-
- VCardResponse *vcard_response_new(unsigned char *buf, int len,
- VCard7816Status status);
-
- This function is similar to vcard_make_response except it includes some
- returned data with the response. It could also fail to allocate enough
- memory, in which case it will return NULL.
-
- VCardResponse *vcard_response_new_status_bytes(unsigned char sw1,
- unsigned char sw2);
-
- Sometimes in 7816 the response bytes are treated as two separate bytes with
- split meanings. This function allows you to create a response based on
- two separate bytes. This function could fail, in which case it will return
- NULL.
-
- VCardResponse *vcard_response_new_bytes(unsigned char *buf, int len,
- unsigned char sw1,
- unsigned char sw2);
-
- This function is the same as vcard_response_new except you may specify
- the status as two separate bytes like vcard_response_new_status_bytes.
-
-
-Implementing functionality ---
-
-The following helper functions access information about the current card
-and applet.
-
- VCARDAppletPrivate *vcard_get_current_applet_private(VCard *card,
- int channel);
-
- This function returns any private data set by the card type emulator on
- the currently selected applet. The card type emulator keeps track of the
- current applet state in this data structure. Any certs and keys associated
- with a particular applet is also stored here.
-
- int vcard_emul_get_login_count(VCard *card);
-
- This function returns the the number of remaing login attempts for this
- card. If the card emulator does not know, or the card does not have a
- way of giving this information, this function returns -1.
-
-
- VCard7816Status vcard_emul_login(VCard *card, unsigned char *pin,
- int pin_len);
-
- This function logins into the card and return the standard 7816 status
- word depending on the success or failure of the call.
-
- void vcard_emul_delete_key(VCardKey *key);
-
- This function frees the VCardKey passed in to xxxx_card_init. The card
- type emulator is responsible for freeing this key when it no longer needs
- it.
-
- VCard7816Status vcard_emul_rsa_op(VCard *card, VCardKey *key,
- unsigned char *buffer,
- int buffer_size);
-
- This function does a raw rsa op on the buffer with the given key.
-
-The sample card type emulator is found in cac.c. It implements the cac specific
-applets. Only those applets needed by the coolkey pkcs#11 driver on the guest
-have been implemented. To support the full range CAC middleware, a complete CAC
-card according to the CAC specs should be implemented here.
-
-------------------------------
-Virtual Card Emulator
-
-This code accesses both real smart cards and simulated smart cards through
-services provided on the client. The current implementation uses NSS, which
-already knows how to talk to various PKCS #11 modules on the client, and is
-portable to most operating systems. A particular emulator can have only one
-virtual card implementation at a time.
-
-The virtual card emulator consists of a series of virtual card services. In
-addition to the services describe above (services starting with
-vcard_emul_xxxx), the virtual card emulator also provides the following
-functions:
-
- VCardEmulError vcard_emul_init(cont VCardEmulOptions *options);
-
- The options structure is built by another function in the virtual card
- interface where a string of virtual card emulator specific strings are
- mapped to the options. The actual structure is defined by the virutal card
- emulator and is used to determine the configuration of soft cards, or to
- determine which physical cards to present to the guest.
-
- The vcard_emul_init function will build up sets of readers, create any
- threads that are needed to watch for changes in the reader state. If readers
- have cards present in them, they are also initialized.
-
- Readers are created with the function.
-
- VReader *vreader_new(VReaderEmul *reader_emul,
- VReaderEmulFree reader_emul_free);
-
- The freeFunc is used to free the VReaderEmul * when the reader is
- destroyed. The VReaderEmul structure is an opaque structure to the
- rest of the code, but defined by the virtual card emulator, which can
- use it to store any reader specific state.
-
- Once the reader has been created, it can be added to the front end with the
- call:
-
- VReaderStatus vreader_add_reader(VReader *reader);
-
- This function will automatically generate the appropriate new reader
- events and add the reader to the list.
-
- To create a new card, the virtual card emulator will call a similiar
- function.
-
- VCard *vcard_new(VCardEmul *card_emul,
- VCardEmulFree card_emul_free);
-
- Like vreader_new, this function takes a virtual card emulator specific
- structure which it uses to keep track of the card state.
-
- Once the card is created, it is attached to a card type emulator with the
- following function:
-
- VCardStatus vcard_init(VCard *vcard, VCardEmulType type,
- const char *flags,
- unsigned char *const *certs,
- int *cert_len,
- VCardKey *key[],
- int cert_count);
-
- The vcard is the value returned from vcard_new. The type is the
- card type emulator that this card should presented to the guest as.
- The flags are card type emulator specific options. The certs,
- cert_len, and keys are all arrays of length cert_count. These are the
- the same of the parameters xxxx_card_init() accepts.
-
- Finally the card is associated with it's reader by the call:
-
- VReaderStatus vreader_insert_card(VReader *vreader, VCard *vcard);
-
- This function, like vreader_add_reader, will take care of any event
- notification for the card insert.
-
-
- VCardEmulError vcard_emul_force_card_remove(VReader *vreader);
-
- Force a card that is present to appear to be removed to the guest, even if
- that card is a physical card and is present.
-
-
- VCardEmulError vcard_emul_force_card_insert(VReader *reader);
-
- Force a card that has been removed by vcard_emul_force_card_remove to be
- reinserted from the point of view of the guest. This will only work if the
- card is physically present (which is always true fro a soft card).
-
- void vcard_emul_get_atr(Vcard *card, unsigned char *atr, int *atr_len);
-
- Return the virtual ATR for the card. By convention this should be the value
- VCARD_ATR_PREFIX(size) followed by several ascii bytes related to this
- particular emulator. For instance the NSS emulator returns
- {VCARD_ATR_PREFIX(3), 'N', 'S', 'S' }. Do ot return more data then *atr_len;
-
- void vcard_emul_reset(VCard *card, VCardPower power)
-
- Set the state of 'card' to the current power level and reset its internal
- state (logout, etc).
-
--------------------------------------------------------
-List of files and their function:
-README - This file
-card_7816.c - emulate basic 7816 functionality. Parse APDUs.
-card_7816.h - apdu and response services definitions.
-card_7816t.h - 7816 specific structures, types and definitions.
-event.c - event handling code.
-event.h - event handling services definitions.
-eventt.h - event handling structures and types
-vcard.c - handle common virtual card services like creation, destruction, and
- applet management.
-vcard.h - common virtual card services function definitions.
-vcardt.h - comon virtual card types
-vreader.c - common virtual reader services.
-vreader.h - common virtual reader services definitions.
-vreadert.h - comon virtual reader types.
-vcard_emul_type.c - manage the card type emulators.
-vcard_emul_type.h - definitions for card type emulators.
-cac.c - card type emulator for CAC cards
-vcard_emul.h - virtual card emulator service definitions.
-vcard_emul_nss.c - virtual card emulator implementation for nss.
-vscclient.c - socket connection to guest qemu usb driver.
-vscard_common.h - common header with the guest qemu usb driver.
-mutex.h - header file for machine independent mutexes.
-link_test.c - static test to make sure all the symbols are properly defined.