libcacard: initial commit

libcacard emulates a Common Access Card (CAC) which is a standard
for smartcards. It is used by the emulated ccid card introduced in
a following patch. Docs are available in docs/libcacard.txt

Signed-off-by: Alon Levy <alevy@redhat.com>

---

changes from v24->v25:
 * Fix out of tree builds.
 * Fix build with linux-user targets.

changes from v23->v24: (Jes Sorensen review 2)
 * Makefile.target: use obj-$(CONFIG_*) +=
 * remove unrequired includes, include qemu-common before qemu-thread
  * required adding #define NO_NSPR_10_SUPPORT (harmless)

changes from v22->v23:
 * configure fixes: (reported by Stefan Hajnoczi)
  * test a = b, not a == b (second isn't portable)
  * quote $source_path in case it contains spaces
   - this doesn't really help since there are many other places
     that need similar fixes, not introduced by this patch.

changes from v21->v22:
 * fix configure to not link libcacard if nss not found
    (reported by Stefan Hajnoczi)
 * fix vscclient linkage with simpletrace backend
    (reported by Stefan Hajnoczi)
 * card_7816.c: add missing break in ERROR_DATA_NOT_FOUND
    (reported by William van de Velde)

changes from v20->v21: (Jes Sorensen review)
 * use qemu infrastructure: qemu-thread, qemu-common (qemu_malloc
  and qemu_free), error_report
 * assert instead of ASSERT
 * cosmetic fixes
 * use strpbrk and isspace
 * add --disable-nss --enable-nss here, instead of in the final patch.
 * split vscclient, passthru and docs to following patches.

changes from v19->v20:
 * checkpatch.pl

changes from v15->v16:

Build:
 * don't erase self with distclean
 * fix make clean after make distclean
 * Makefile: make vscclient link quiet

Behavioral:
 * vcard_emul_nss: load coolkey in more situations
 * vscclient:
  * use hton,ntoh
  * send init on connect, only start vevent thread on response
  * read payload after header check, before type switch
  * remove Reconnect
  * update for vscard_common changes, empty Flush implementation

Style/Whitespace:
 * fix wrong variable usage
 * remove unused variable
 * use only C style comments
  * add copyright header
  * fix tabulation

Signed-off-by: Alon Levy <alevy@redhat.com>

libcacard: fix out of tree builds

1 files changed, 403 insertions, 0 deletions

diff --git a/libcacard/cac.c b/libcacard/cac.c
new file mode 100644
index 0000000..f34f63a
--- /dev/null
+++ b/libcacard/cac.c
@@ -0,0 +1,403 @@
+/*
+ * implement the applets for the CAC card.
+ *
+ * This code is licensed under the GNU LGPL, version 2.1 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ */
+
+#include "qemu-common.h"
+
+#include "cac.h"
+#include "vcard.h"
+#include "vcard_emul.h"
+#include "card_7816.h"
+
+#define CAC_GET_PROPERTIES  0x56
+#define CAC_GET_ACR         0x4c
+#define CAC_READ_BUFFER     0x52
+#define CAC_UPDATE_BUFFER   0x58
+#define CAC_SIGN_DECRYPT    0x42
+#define CAC_GET_CERTIFICATE 0x36
+
+/* private data for PKI applets */
+typedef struct CACPKIAppletDataStruct {
+    unsigned char *cert;
+    int cert_len;
+    unsigned char *cert_buffer;
+    int cert_buffer_len;
+    unsigned char *sign_buffer;
+    int sign_buffer_len;
+    VCardKey *key;
+} CACPKIAppletData;
+
+/*
+ * CAC applet private data
+ */
+struct VCardAppletPrivateStruct {
+    union {
+        CACPKIAppletData pki_data;
+        void *reserved;
+    } u;
+};
+
+/*
+ * handle all the APDU's that are common to all CAC applets
+ */
+static VCardStatus
+cac_common_process_apdu(VCard *card, VCardAPDU *apdu, VCardResponse **response)
+{
+    int ef;
+
+    switch (apdu->a_ins) {
+    case VCARD7816_INS_SELECT_FILE:
+        if (apdu->a_p1 != 0x02) {
+            /* let the 7816 code handle applet switches */
+            return VCARD_NEXT;
+        }
+        /* handle file id setting */
+        if (apdu->a_Lc != 2) {
+            *response = vcard_make_response(
+                VCARD7816_STATUS_ERROR_DATA_INVALID);
+            return VCARD_DONE;
+        }
+        /* CAC 1.0 only supports ef = 0 */
+        ef = apdu->a_body[0] | (apdu->a_body[1] << 8);
+        if (ef != 0) {
+            *response = vcard_make_response(
+                VCARD7816_STATUS_ERROR_FILE_NOT_FOUND);
+            return VCARD_DONE;
+        }
+        *response = vcard_make_response(VCARD7816_STATUS_SUCCESS);
+        return VCARD_DONE;
+    case VCARD7816_INS_GET_RESPONSE:
+    case VCARD7816_INS_VERIFY:
+        /* let the 7816 code handle these */
+        return VCARD_NEXT;
+    case CAC_GET_PROPERTIES:
+    case CAC_GET_ACR:
+        /* skip these for now, this will probably be needed */
+        *response = vcard_make_response(VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
+        return VCARD_DONE;
+    }
+    *response = vcard_make_response(
+        VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
+    return VCARD_DONE;
+}
+
+/*
+ *  reset the inter call state between applet selects
+ */
+static VCardStatus
+cac_applet_pki_reset(VCard *card, int channel)
+{
+    VCardAppletPrivate *applet_private = NULL;
+    CACPKIAppletData *pki_applet = NULL;
+    applet_private = vcard_get_current_applet_private(card, channel);
+    assert(applet_private);
+    pki_applet = &(applet_private->u.pki_data);
+
+    pki_applet->cert_buffer = NULL;
+    if (pki_applet->sign_buffer) {
+        qemu_free(pki_applet->sign_buffer);
+        pki_applet->sign_buffer = NULL;
+    }
+    pki_applet->cert_buffer_len = 0;
+    pki_applet->sign_buffer_len = 0;
+    return VCARD_DONE;
+}
+
+static VCardStatus
+cac_applet_pki_process_apdu(VCard *card, VCardAPDU *apdu,
+                            VCardResponse **response)
+{
+    CACPKIAppletData *pki_applet = NULL;
+    VCardAppletPrivate *applet_private = NULL;
+    int size, next;
+    unsigned char *sign_buffer;
+    vcard_7816_status_t status;
+
+    applet_private = vcard_get_current_applet_private(card, apdu->a_channel);
+    assert(applet_private);
+    pki_applet = &(applet_private->u.pki_data);
+
+    switch (apdu->a_ins) {
+    case CAC_UPDATE_BUFFER:
+        *response = vcard_make_response(
+            VCARD7816_STATUS_ERROR_CONDITION_NOT_SATISFIED);
+        return VCARD_DONE;
+    case CAC_GET_CERTIFICATE:
+        if ((apdu->a_p2 != 0) || (apdu->a_p1 != 0)) {
+            *response = vcard_make_response(
+                             VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
+            break;
+        }
+        assert(pki_applet->cert != NULL);
+        size = apdu->a_Le;
+        if (pki_applet->cert_buffer == NULL) {
+            pki_applet->cert_buffer = pki_applet->cert;
+            pki_applet->cert_buffer_len = pki_applet->cert_len;
+        }
+        size = MIN(size, pki_applet->cert_buffer_len);
+        next = MIN(255, pki_applet->cert_buffer_len - size);
+        *response = vcard_response_new_bytes(
+                        card, pki_applet->cert_buffer, size,
+                        apdu->a_Le, next ?
+                        VCARD7816_SW1_WARNING_CHANGE :
+                        VCARD7816_SW1_SUCCESS,
+                        next);
+        pki_applet->cert_buffer += size;
+        pki_applet->cert_buffer_len -= size;
+        if ((*response == NULL) || (next == 0)) {
+            pki_applet->cert_buffer = NULL;
+        }
+        if (*response == NULL) {
+            *response = vcard_make_response(
+                            VCARD7816_STATUS_EXC_ERROR_MEMORY_FAILURE);
+        }
+        return VCARD_DONE;
+    case CAC_SIGN_DECRYPT:
+        if (apdu->a_p2 != 0) {
+            *response = vcard_make_response(
+                             VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
+            break;
+        }
+        size = apdu->a_Lc;
+
+        sign_buffer = realloc(pki_applet->sign_buffer,
+                      pki_applet->sign_buffer_len+size);
+        if (sign_buffer == NULL) {
+            qemu_free(pki_applet->sign_buffer);
+            pki_applet->sign_buffer = NULL;
+            pki_applet->sign_buffer_len = 0;
+            *response = vcard_make_response(
+                            VCARD7816_STATUS_EXC_ERROR_MEMORY_FAILURE);
+            return VCARD_DONE;
+        }
+        memcpy(sign_buffer+pki_applet->sign_buffer_len, apdu->a_body, size);
+        size += pki_applet->sign_buffer_len;
+        switch (apdu->a_p1) {
+        case  0x80:
+            /* p1 == 0x80 means we haven't yet sent the whole buffer, wait for
+             * the rest */
+            pki_applet->sign_buffer = sign_buffer;
+            pki_applet->sign_buffer_len = size;
+            *response = vcard_make_response(VCARD7816_STATUS_SUCCESS);
+            return VCARD_DONE;
+        case 0x00:
+            /* we now have the whole buffer, do the operation, result will be
+             * in the sign_buffer */
+            status = vcard_emul_rsa_op(card, pki_applet->key,
+                                       sign_buffer, size);
+            if (status != VCARD7816_STATUS_SUCCESS) {
+                *response = vcard_make_response(status);
+                break;
+            }
+            *response = vcard_response_new(card, sign_buffer, size, apdu->a_Le,
+                                                     VCARD7816_STATUS_SUCCESS);
+            if (*response == NULL) {
+                *response = vcard_make_response(
+                                VCARD7816_STATUS_EXC_ERROR_MEMORY_FAILURE);
+            }
+            break;
+        default:
+           *response = vcard_make_response(
+                                VCARD7816_STATUS_ERROR_P1_P2_INCORRECT);
+            break;
+        }
+        qemu_free(sign_buffer);
+        pki_applet->sign_buffer = NULL;
+        pki_applet->sign_buffer_len = 0;
+        return VCARD_DONE;
+    case CAC_READ_BUFFER:
+        /* new CAC call, go ahead and use the old version for now */
+        /* TODO: implement */
+        *response = vcard_make_response(
+                                VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
+        return VCARD_DONE;
+    }
+    return cac_common_process_apdu(card, apdu, response);
+}
+
+
+static VCardStatus
+cac_applet_id_process_apdu(VCard *card, VCardAPDU *apdu,
+                           VCardResponse **response)
+{
+    switch (apdu->a_ins) {
+    case CAC_UPDATE_BUFFER:
+        *response = vcard_make_response(
+                        VCARD7816_STATUS_ERROR_CONDITION_NOT_SATISFIED);
+        return VCARD_DONE;
+    case CAC_READ_BUFFER:
+        /* new CAC call, go ahead and use the old version for now */
+        /* TODO: implement */
+        *response = vcard_make_response(
+                        VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
+        return VCARD_DONE;
+    }
+    return cac_common_process_apdu(card, apdu, response);
+}
+
+
+/*
+ * TODO: if we ever want to support general CAC middleware, we will need to
+ * implement the various containers.
+ */
+static VCardStatus
+cac_applet_container_process_apdu(VCard *card, VCardAPDU *apdu,
+                                  VCardResponse **response)
+{
+    switch (apdu->a_ins) {
+    case CAC_READ_BUFFER:
+    case CAC_UPDATE_BUFFER:
+        *response = vcard_make_response(
+                        VCARD7816_STATUS_ERROR_COMMAND_NOT_SUPPORTED);
+        return VCARD_DONE;
+    default:
+        break;
+    }
+    return cac_common_process_apdu(card, apdu, response);
+}
+
+/*
+ * utilities for creating and destroying the private applet data
+ */
+static void
+cac_delete_pki_applet_private(VCardAppletPrivate *applet_private)
+{
+    CACPKIAppletData *pki_applet_data = NULL;
+    if (pki_applet_data == NULL) {
+        return;
+    }
+    pki_applet_data = &(applet_private->u.pki_data);
+    if (pki_applet_data->cert != NULL) {
+        qemu_free(pki_applet_data->cert);
+    }
+    if (pki_applet_data->sign_buffer != NULL) {
+        qemu_free(pki_applet_data->sign_buffer);
+    }
+    if (pki_applet_data->key != NULL) {
+        vcard_emul_delete_key(pki_applet_data->key);
+    }
+    qemu_free(applet_private);
+}
+
+static VCardAppletPrivate *
+cac_new_pki_applet_private(const unsigned char *cert,
+                           int cert_len, VCardKey *key)
+{
+    CACPKIAppletData *pki_applet_data = NULL;
+    VCardAppletPrivate *applet_private = NULL;
+    applet_private = (VCardAppletPrivate *)qemu_malloc(sizeof(VCardAppletPrivate));
+
+    pki_applet_data = &(applet_private->u.pki_data);
+    pki_applet_data->cert_buffer = NULL;
+    pki_applet_data->cert_buffer_len = 0;
+    pki_applet_data->sign_buffer = NULL;
+    pki_applet_data->sign_buffer_len = 0;
+    pki_applet_data->key = NULL;
+    pki_applet_data->cert = (unsigned char *)qemu_malloc(cert_len+1);
+    /*
+     * if we want to support compression, then we simply change the 0 to a 1
+     * and compress the cert data with libz
+     */
+    pki_applet_data->cert[0] = 0; /* not compressed */
+    memcpy(&pki_applet_data->cert[1], cert, cert_len);
+    pki_applet_data->cert_len = cert_len+1;
+
+    pki_applet_data->key = key;
+    return applet_private;
+}
+
+
+/*
+ * create a new cac applet which links to a given cert
+ */
+static VCardApplet *
+cac_new_pki_applet(int i, const unsigned char *cert,
+                   int cert_len, VCardKey *key)
+{
+    VCardAppletPrivate *applet_private = NULL;
+    VCardApplet *applet = NULL;
+    unsigned char pki_aid[] = { 0xa0, 0x00, 0x00, 0x00, 0x79, 0x01, 0x00 };
+    int pki_aid_len = sizeof(pki_aid);
+
+    pki_aid[pki_aid_len-1] = i;
+
+    applet_private = cac_new_pki_applet_private(cert, cert_len, key);
+    if (applet_private == NULL) {
+        goto failure;
+    }
+    applet = vcard_new_applet(cac_applet_pki_process_apdu, cac_applet_pki_reset,
+                              pki_aid, pki_aid_len);
+    if (applet == NULL) {
+        goto failure;
+    }
+    vcard_set_applet_private(applet, applet_private,
+                             cac_delete_pki_applet_private);
+    applet_private = NULL;
+
+    return applet;
+
+failure:
+    if (applet_private != NULL) {
+        cac_delete_pki_applet_private(applet_private);
+    }
+    return NULL;
+}
+
+
+static unsigned char cac_default_container_aid[] = {
+    0xa0, 0x00, 0x00, 0x00, 0x30, 0x00, 0x00 };
+static unsigned char cac_id_aid[] = {
+    0xa0, 0x00, 0x00, 0x00, 0x79, 0x03, 0x00 };
+/*
+ * Initialize the cac card. This is the only public function in this file. All
+ * the rest are connected through function pointers.
+ */
+VCardStatus
+cac_card_init(VReader *reader, VCard *card,
+              const char *params,
+              unsigned char * const *cert,
+              int cert_len[],
+              VCardKey *key[] /* adopt the keys*/,
+              int cert_count)
+{
+    int i;
+    VCardApplet *applet;
+
+    /* CAC Cards are VM Cards */
+    vcard_set_type(card, VCARD_VM);
+
+    /* create one PKI applet for each cert */
+    for (i = 0; i < cert_count; i++) {
+        applet = cac_new_pki_applet(i, cert[i], cert_len[i], key[i]);
+        if (applet == NULL) {
+            goto failure;
+        }
+        vcard_add_applet(card, applet);
+    }
+
+    /* create a default blank container applet */
+    applet = vcard_new_applet(cac_applet_container_process_apdu,
+                              NULL, cac_default_container_aid,
+                              sizeof(cac_default_container_aid));
+    if (applet == NULL) {
+        goto failure;
+    }
+    vcard_add_applet(card, applet);
+
+    /* create a default blank container applet */
+    applet = vcard_new_applet(cac_applet_id_process_apdu,
+                              NULL, cac_id_aid,
+                              sizeof(cac_id_aid));
+    if (applet == NULL) {
+        goto failure;
+    }
+    vcard_add_applet(card, applet);
+    return VCARD_DONE;
+
+failure:
+    return VCARD_FAIL;
+}
+