diff mbox

[v23,07/11] libcacard: add vscclient

Message ID 1300886393-2799-8-git-send-email-alevy@redhat.com
State New
Headers show

Commit Message

Alon Levy March 23, 2011, 1:19 p.m. UTC
From: Robert Relyea <rrelyea@redhat.com>

client to talk to ccid-card-passthru and use smartcard on client to
perform actual operations.
---
 libcacard/Makefile    |    7 +-
 libcacard/vscclient.c |  730 +++++++++++++++++++++++++++++++++++++++++++++++++
 2 files changed, 736 insertions(+), 1 deletions(-)
 create mode 100644 libcacard/vscclient.c

Comments

Jes Sorensen March 28, 2011, 12:43 p.m. UTC | #1
On 03/23/11 14:19, Alon Levy wrote:
> From: Robert Relyea <rrelyea@redhat.com>
> 
> client to talk to ccid-card-passthru and use smartcard on client to
> perform actual operations.
> ---
>  libcacard/Makefile    |    7 +-
>  libcacard/vscclient.c |  730 +++++++++++++++++++++++++++++++++++++++++++++++++
>  2 files changed, 736 insertions(+), 1 deletions(-)
>  create mode 100644 libcacard/vscclient.c
> 
[snip]
> diff --git a/libcacard/vscclient.c b/libcacard/vscclient.c
> new file mode 100644
> index 0000000..8dde449
> --- /dev/null
> +++ b/libcacard/vscclient.c
> @@ -0,0 +1,730 @@
> +/*
> + * Tester for VSCARD protocol, client side.
> + *
> + * Can be used with ccid-card-passthru.
> + *
> + * Copyright (c) 2011 Red Hat.
> + * Written by Alon Levy.
> + *
> + * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
> + * See the COPYING.LIB file in the top-level directory.
> + */
> +
> +#include <sys/types.h>
> +#include <stdio.h>
> +#include <stdlib.h>
> +#include <string.h>
> +#include <unistd.h>
> +
> +#include <sys/types.h>
> +#include <sys/socket.h>
> +#include <netdb.h>
> +#include <netinet/in.h>
> +#include <arpa/inet.h>
> +
> +#include "qemu-thread.h"
> +#include "qemu-common.h"

Lots of unnecessary includes here.


> +    if (verbose > 10) {
> +        printf("sending type=%d id=%d, len =%d (0x%x)\n",
> +               type, reader_id, length, length);
> +    }
> +
> +    mhHeader.type = htonl(type);
> +    mhHeader.reader_id = 0;
> +    mhHeader.length = htonl(length);
> +    rv = write(
> +        sock,
> +        &mhHeader,
> +        sizeof(mhHeader)
> +    );

Is this excessive multi-lining necessary? It makes it really hard to read.

> +    if (rv < 0) {
> +        /* Error */
> +        printf("write header error\n");
> +        close(sock);
> +        qemu_mutex_unlock(&write_lock);
> +        return 16;
> +    }

Shouldn't errors go to stderr ?

> +    rv = write(
> +        sock,
> +        msg,
> +        length
> +    );
> +    if (rv < 0) {
> +        /* Error */
> +        printf("write error\n");
> +        close(sock);
> +        qemu_mutex_unlock(&write_lock);
> +        return 16;
> +    }

Same here.

> +static void
> +do_command(void)
> +{
> +    char inbuf[255];
> +    char *string;
> +    VCardEmulError error;
> +    static unsigned int default_reader_id;
> +    unsigned int reader_id;
> +    VReader *reader = NULL;
> +
> +    reader_id = default_reader_id;
> +    string = fgets(inbuf, sizeof(inbuf), stdin);
> +    if (string != NULL) {
> +        if (strncmp(string, "exit", 4) == 0) {
> +            /* remove all the readers */
> +            VReaderList *list = vreader_get_reader_list();
> +            VReaderListEntry *reader_entry;
> +            printf("Active Readers:\n");
> +            for (reader_entry = vreader_list_get_first(list); reader_entry;
> +                 reader_entry = vreader_list_get_next(reader_entry)) {
> +                VReader *reader = vreader_list_get_reader(reader_entry);
> +                vreader_id_t reader_id;
> +                reader_id = vreader_get_id(reader);
> +                if (reader_id == -1) {
> +                    continue;
> +                }
> +                /* be nice and signal card removal first (qemu probably should
> +                 * do this itself) */
> +                if (vreader_card_is_present(reader) == VREADER_OK) {
> +                    send_msg(
> +                        VSC_CardRemove,
> +                        reader_id,
> +                        NULL,
> +                        0
> +                    );
> +                }
> +                send_msg(
> +                    VSC_ReaderRemove,
> +                    reader_id,
> +                    NULL,
> +                    0
> +                );
> +            }
> +            exit(0);
> +        } else if (strncmp(string, "insert", 6) == 0) {
> +            if (string[6] == ' ') {
> +                reader_id = get_id_from_string(&string[7], reader_id);
> +            }
> +            reader = vreader_get_reader_by_id(reader_id);
> +            if (reader != NULL) {
> +                error = vcard_emul_force_card_insert(reader);
> +                printf("insert %s, returned %d\n",
> +                       reader ? vreader_get_name(reader)
> +                       : "invalid reader", error);
> +            } else {
> +                printf("no reader by id %d found\n", reader_id);
> +            }
> +        } else if (strncmp(string, "remove", 6) == 0) {
> +            if (string[6] == ' ') {
> +                reader_id = get_id_from_string(&string[7], reader_id);
> +            }
> +            reader = vreader_get_reader_by_id(reader_id);
> +            if (reader != NULL) {
> +                error = vcard_emul_force_card_remove(reader);
> +                printf("remove %s, returned %d\n",
> +                        reader ? vreader_get_name(reader)
> +                        : "invalid reader", error);
> +            } else {
> +                printf("no reader by id %d found\n", reader_id);
> +            }
> +        } else if (strncmp(string, "select", 6) == 0) {
> +            if (string[6] == ' ') {
> +                reader_id = get_id_from_string(&string[7],
> +                                               VSCARD_UNDEFINED_READER_ID);
> +            }
> +            if (reader_id != VSCARD_UNDEFINED_READER_ID) {
> +                reader = vreader_get_reader_by_id(reader_id);
> +            }
> +            if (reader) {
> +                printf("Selecting reader %d, %s\n", reader_id,
> +                        vreader_get_name(reader));
> +                default_reader_id = reader_id;
> +            } else {
> +                printf("Reader with id %d not found\n", reader_id);
> +            }
> +        } else if (strncmp(string, "debug", 5) == 0) {
> +            if (string[5] == ' ') {
> +                verbose = get_id_from_string(&string[6], 0);
> +            }
> +            printf("debug level = %d\n", verbose);
> +        } else if (strncmp(string, "list", 4) == 0) {
> +            VReaderList *list = vreader_get_reader_list();
> +            VReaderListEntry *reader_entry;
> +            printf("Active Readers:\n");
> +            for (reader_entry = vreader_list_get_first(list); reader_entry;
> +                 reader_entry = vreader_list_get_next(reader_entry)) {
> +                VReader *reader = vreader_list_get_reader(reader_entry);
> +                vreader_id_t reader_id;
> +                reader_id = vreader_get_id(reader);
> +                if (reader_id == -1) {
> +                    continue;
> +                }
> +                printf("%3d %s %s\n", reader_id,
> +                       vreader_card_is_present(reader) == VREADER_OK ?
> +                       "CARD_PRESENT" : "            ",
> +                       vreader_get_name(reader));
> +            }
> +            printf("Inactive Readers:\n");
> +            for (reader_entry = vreader_list_get_first(list); reader_entry;
> +                 reader_entry = vreader_list_get_next(reader_entry)) {
> +                VReader *reader = vreader_list_get_reader(reader_entry);
> +                vreader_id_t reader_id;
> +                reader_id = vreader_get_id(reader);
> +                if (reader_id != -1) {
> +                    continue;
> +                }
> +
> +                printf("INA %s %s\n",
> +                       vreader_card_is_present(reader) == VREADER_OK ?
> +                       "CARD_PRESENT" : "            ",
> +                       vreader_get_name(reader));
> +            }
> +        } else if (*string != 0) {
> +            printf("valid commands:\n");
> +            printf("insert [reader_id]\n");
> +            printf("remove [reader_id]\n");
> +            printf("select reader_id\n");
> +            printf("list\n");
> +            printf("debug [level]\n");
> +            printf("exit\n");
> +        }
> +    }
> +    vreader_free(reader);
> +    printf("> ");
> +    fflush(stdout);
> +}
> +
> +
> +#define APDUBufSize 270
> +
> +/* just for ease of parsing command line arguments. */
> +#define MAX_CERTS 100
> +
> +static int
> +connect_to_qemu(
> +    const char *host,
> +    const char *port
> +) {
> +    struct addrinfo hints;
> +    struct addrinfo *server;
> +    int ret;
> +
> +    sock = socket(
> +        AF_INET,
> +        SOCK_STREAM,
> +        0
> +    );

We have qemu_socket() for portability.

> +    if (sock < 0) {
> +        /* Error */
> +        printf("Error opening socket!\n");
> +    }
> +
> +    memset(&hints, 0, sizeof(struct addrinfo));
> +    hints.ai_family = AF_UNSPEC;
> +    hints.ai_socktype = SOCK_STREAM;
> +    hints.ai_flags = 0;
> +    hints.ai_protocol = 0;          /* Any protocol */
> +
> +    ret = getaddrinfo(host, port, &hints, &server);
> +
> +    if (ret != 0) {
> +        printf("getaddrinfo failed\n");
> +        return 5;
> +    }

Juan just posted code to handle addrinfo and other bits that also
includes ipv6 support. You may want to look at that for a later update.

> +static int on_host_init(VSCMsgHeader *mhHeader, VSCMsgInit *incoming)
> +{
> +    uint32_t *capabilities = (incoming->capabilities);
> +    int num_capabilities =
> +        1 + ((mhHeader->length - sizeof(VSCMsgInit)) / sizeof(uint32_t));
> +    int i;
> +    int rv;
> +    pthread_t thread_id;
> +
> +    incoming->version = ntohl(incoming->version);
> +    if (incoming->version != VSCARD_VERSION) {
> +        if (verbose > 0) {
> +            printf("warning: host has version %d, we have %d\n",
> +                verbose, VSCARD_VERSION);
> +        }
> +    }
> +    if (incoming->magic != VSCARD_MAGIC) {

as mentioned in an earlier series, I think VSCARD_MAGIC needs to be
network converted too, to handle difference in endianness between hosts.

Cheers,
Jes
Alon Levy March 28, 2011, 12:51 p.m. UTC | #2
On Mon, Mar 28, 2011 at 02:43:38PM +0200, Jes Sorensen wrote:
> On 03/23/11 14:19, Alon Levy wrote:
> > From: Robert Relyea <rrelyea@redhat.com>
> > 
> > client to talk to ccid-card-passthru and use smartcard on client to
> > perform actual operations.
> > ---
> >  libcacard/Makefile    |    7 +-
> >  libcacard/vscclient.c |  730 +++++++++++++++++++++++++++++++++++++++++++++++++
> >  2 files changed, 736 insertions(+), 1 deletions(-)
> >  create mode 100644 libcacard/vscclient.c
> > 
> [snip]
> > diff --git a/libcacard/vscclient.c b/libcacard/vscclient.c
> > new file mode 100644
> > index 0000000..8dde449
> > --- /dev/null
> > +++ b/libcacard/vscclient.c
> > @@ -0,0 +1,730 @@
> > +/*
> > + * Tester for VSCARD protocol, client side.
> > + *
> > + * Can be used with ccid-card-passthru.
> > + *
> > + * Copyright (c) 2011 Red Hat.
> > + * Written by Alon Levy.
> > + *
> > + * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
> > + * See the COPYING.LIB file in the top-level directory.
> > + */
> > +
> > +#include <sys/types.h>
> > +#include <stdio.h>
> > +#include <stdlib.h>
> > +#include <string.h>
> > +#include <unistd.h>
> > +
> > +#include <sys/types.h>
> > +#include <sys/socket.h>
> > +#include <netdb.h>
> > +#include <netinet/in.h>
> > +#include <arpa/inet.h>
> > +
> > +#include "qemu-thread.h"
> > +#include "qemu-common.h"
> 
> Lots of unnecessary includes here.
Will fix.

> 
> 
> > +    if (verbose > 10) {
> > +        printf("sending type=%d id=%d, len =%d (0x%x)\n",
> > +               type, reader_id, length, length);
> > +    }
> > +
> > +    mhHeader.type = htonl(type);
> > +    mhHeader.reader_id = 0;
> > +    mhHeader.length = htonl(length);
> > +    rv = write(
> > +        sock,
> > +        &mhHeader,
> > +        sizeof(mhHeader)
> > +    );
> 
> Is this excessive multi-lining necessary? It makes it really hard to read.
It's a loop hole in the coding standard? ok, will fix.

> 
> > +    if (rv < 0) {
> > +        /* Error */
> > +        printf("write header error\n");
> > +        close(sock);
> > +        qemu_mutex_unlock(&write_lock);
> > +        return 16;
> > +    }
> 
> Shouldn't errors go to stderr ?
will fix.

> 
> > +    rv = write(
> > +        sock,
> > +        msg,
> > +        length
> > +    );
> > +    if (rv < 0) {
> > +        /* Error */
> > +        printf("write error\n");
> > +        close(sock);
> > +        qemu_mutex_unlock(&write_lock);
> > +        return 16;
> > +    }
> 
> Same here.
will fix.

> 
> > +static void
> > +do_command(void)
> > +{
> > +    char inbuf[255];
> > +    char *string;
> > +    VCardEmulError error;
> > +    static unsigned int default_reader_id;
> > +    unsigned int reader_id;
> > +    VReader *reader = NULL;
> > +
> > +    reader_id = default_reader_id;
> > +    string = fgets(inbuf, sizeof(inbuf), stdin);
> > +    if (string != NULL) {
> > +        if (strncmp(string, "exit", 4) == 0) {
> > +            /* remove all the readers */
> > +            VReaderList *list = vreader_get_reader_list();
> > +            VReaderListEntry *reader_entry;
> > +            printf("Active Readers:\n");
> > +            for (reader_entry = vreader_list_get_first(list); reader_entry;
> > +                 reader_entry = vreader_list_get_next(reader_entry)) {
> > +                VReader *reader = vreader_list_get_reader(reader_entry);
> > +                vreader_id_t reader_id;
> > +                reader_id = vreader_get_id(reader);
> > +                if (reader_id == -1) {
> > +                    continue;
> > +                }
> > +                /* be nice and signal card removal first (qemu probably should
> > +                 * do this itself) */
> > +                if (vreader_card_is_present(reader) == VREADER_OK) {
> > +                    send_msg(
> > +                        VSC_CardRemove,
> > +                        reader_id,
> > +                        NULL,
> > +                        0
> > +                    );
> > +                }
> > +                send_msg(
> > +                    VSC_ReaderRemove,
> > +                    reader_id,
> > +                    NULL,
> > +                    0
> > +                );
> > +            }
> > +            exit(0);
> > +        } else if (strncmp(string, "insert", 6) == 0) {
> > +            if (string[6] == ' ') {
> > +                reader_id = get_id_from_string(&string[7], reader_id);
> > +            }
> > +            reader = vreader_get_reader_by_id(reader_id);
> > +            if (reader != NULL) {
> > +                error = vcard_emul_force_card_insert(reader);
> > +                printf("insert %s, returned %d\n",
> > +                       reader ? vreader_get_name(reader)
> > +                       : "invalid reader", error);
> > +            } else {
> > +                printf("no reader by id %d found\n", reader_id);
> > +            }
> > +        } else if (strncmp(string, "remove", 6) == 0) {
> > +            if (string[6] == ' ') {
> > +                reader_id = get_id_from_string(&string[7], reader_id);
> > +            }
> > +            reader = vreader_get_reader_by_id(reader_id);
> > +            if (reader != NULL) {
> > +                error = vcard_emul_force_card_remove(reader);
> > +                printf("remove %s, returned %d\n",
> > +                        reader ? vreader_get_name(reader)
> > +                        : "invalid reader", error);
> > +            } else {
> > +                printf("no reader by id %d found\n", reader_id);
> > +            }
> > +        } else if (strncmp(string, "select", 6) == 0) {
> > +            if (string[6] == ' ') {
> > +                reader_id = get_id_from_string(&string[7],
> > +                                               VSCARD_UNDEFINED_READER_ID);
> > +            }
> > +            if (reader_id != VSCARD_UNDEFINED_READER_ID) {
> > +                reader = vreader_get_reader_by_id(reader_id);
> > +            }
> > +            if (reader) {
> > +                printf("Selecting reader %d, %s\n", reader_id,
> > +                        vreader_get_name(reader));
> > +                default_reader_id = reader_id;
> > +            } else {
> > +                printf("Reader with id %d not found\n", reader_id);
> > +            }
> > +        } else if (strncmp(string, "debug", 5) == 0) {
> > +            if (string[5] == ' ') {
> > +                verbose = get_id_from_string(&string[6], 0);
> > +            }
> > +            printf("debug level = %d\n", verbose);
> > +        } else if (strncmp(string, "list", 4) == 0) {
> > +            VReaderList *list = vreader_get_reader_list();
> > +            VReaderListEntry *reader_entry;
> > +            printf("Active Readers:\n");
> > +            for (reader_entry = vreader_list_get_first(list); reader_entry;
> > +                 reader_entry = vreader_list_get_next(reader_entry)) {
> > +                VReader *reader = vreader_list_get_reader(reader_entry);
> > +                vreader_id_t reader_id;
> > +                reader_id = vreader_get_id(reader);
> > +                if (reader_id == -1) {
> > +                    continue;
> > +                }
> > +                printf("%3d %s %s\n", reader_id,
> > +                       vreader_card_is_present(reader) == VREADER_OK ?
> > +                       "CARD_PRESENT" : "            ",
> > +                       vreader_get_name(reader));
> > +            }
> > +            printf("Inactive Readers:\n");
> > +            for (reader_entry = vreader_list_get_first(list); reader_entry;
> > +                 reader_entry = vreader_list_get_next(reader_entry)) {
> > +                VReader *reader = vreader_list_get_reader(reader_entry);
> > +                vreader_id_t reader_id;
> > +                reader_id = vreader_get_id(reader);
> > +                if (reader_id != -1) {
> > +                    continue;
> > +                }
> > +
> > +                printf("INA %s %s\n",
> > +                       vreader_card_is_present(reader) == VREADER_OK ?
> > +                       "CARD_PRESENT" : "            ",
> > +                       vreader_get_name(reader));
> > +            }
> > +        } else if (*string != 0) {
> > +            printf("valid commands:\n");
> > +            printf("insert [reader_id]\n");
> > +            printf("remove [reader_id]\n");
> > +            printf("select reader_id\n");
> > +            printf("list\n");
> > +            printf("debug [level]\n");
> > +            printf("exit\n");
> > +        }
> > +    }
> > +    vreader_free(reader);
> > +    printf("> ");
> > +    fflush(stdout);
> > +}
> > +
> > +
> > +#define APDUBufSize 270
> > +
> > +/* just for ease of parsing command line arguments. */
> > +#define MAX_CERTS 100
> > +
> > +static int
> > +connect_to_qemu(
> > +    const char *host,
> > +    const char *port
> > +) {
> > +    struct addrinfo hints;
> > +    struct addrinfo *server;
> > +    int ret;
> > +
> > +    sock = socket(
> > +        AF_INET,
> > +        SOCK_STREAM,
> > +        0
> > +    );
> 
> We have qemu_socket() for portability.
ok, will use.

> 
> > +    if (sock < 0) {
> > +        /* Error */
> > +        printf("Error opening socket!\n");
> > +    }
> > +
> > +    memset(&hints, 0, sizeof(struct addrinfo));
> > +    hints.ai_family = AF_UNSPEC;
> > +    hints.ai_socktype = SOCK_STREAM;
> > +    hints.ai_flags = 0;
> > +    hints.ai_protocol = 0;          /* Any protocol */
> > +
> > +    ret = getaddrinfo(host, port, &hints, &server);
> > +
> > +    if (ret != 0) {
> > +        printf("getaddrinfo failed\n");
> > +        return 5;
> > +    }
> 
> Juan just posted code to handle addrinfo and other bits that also
> includes ipv6 support. You may want to look at that for a later update.
> 
ok.

> > +static int on_host_init(VSCMsgHeader *mhHeader, VSCMsgInit *incoming)
> > +{
> > +    uint32_t *capabilities = (incoming->capabilities);
> > +    int num_capabilities =
> > +        1 + ((mhHeader->length - sizeof(VSCMsgInit)) / sizeof(uint32_t));
> > +    int i;
> > +    int rv;
> > +    pthread_t thread_id;
> > +
> > +    incoming->version = ntohl(incoming->version);
> > +    if (incoming->version != VSCARD_VERSION) {
> > +        if (verbose > 0) {
> > +            printf("warning: host has version %d, we have %d\n",
> > +                verbose, VSCARD_VERSION);
> > +        }
> > +    }
> > +    if (incoming->magic != VSCARD_MAGIC) {
> 
> as mentioned in an earlier series, I think VSCARD_MAGIC needs to be
> network converted too, to handle difference in endianness between hosts.
Same answer as to your previous comment.

> 
> Cheers,
> Jes
Jes Sorensen March 28, 2011, 1:55 p.m. UTC | #3
On 03/28/11 14:51, Alon Levy wrote:
>> > as mentioned in an earlier series, I think VSCARD_MAGIC needs to be
>> > network converted too, to handle difference in endianness between hosts.
> Same answer as to your previous comment.
> 

Yeah I saw your answer - I am happy with the code in general, so if you
fix the minor nits that is good with me.

Cheers,
Jes
diff mbox

Patch

diff --git a/libcacard/Makefile b/libcacard/Makefile
index 410fa1e..85e3376 100644
--- a/libcacard/Makefile
+++ b/libcacard/Makefile
@@ -12,6 +12,11 @@  endif
 
 QEMU_OBJS=$(QEMU_THREAD) $(oslib-obj-y) $(trace-obj-y) qemu-malloc.o qemu-timer-common.o
 
+vscclient: $(libcacard-y) $(QEMU_OBJS) vscclient.o
+	$(call quiet-command,$(CC) $(libcacard_libs) -lrt -o $@ $^,"  LINK  $(TARGET_DIR)$@")
+
+all: vscclient
+
 clean:
-	rm -f *.o */*.o *.d */*.d *.a */*.a *~ */*~
+	rm -f *.o */*.o *.d */*.d *.a */*.a *~ */*~ vscclient
 
diff --git a/libcacard/vscclient.c b/libcacard/vscclient.c
new file mode 100644
index 0000000..8dde449
--- /dev/null
+++ b/libcacard/vscclient.c
@@ -0,0 +1,730 @@ 
+/*
+ * Tester for VSCARD protocol, client side.
+ *
+ * Can be used with ccid-card-passthru.
+ *
+ * Copyright (c) 2011 Red Hat.
+ * Written by Alon Levy.
+ *
+ * This work is licensed under the terms of the GNU LGPL, version 2.1 or later.
+ * See the COPYING.LIB file in the top-level directory.
+ */
+
+#include <sys/types.h>
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <unistd.h>
+
+#include <sys/types.h>
+#include <sys/socket.h>
+#include <netdb.h>
+#include <netinet/in.h>
+#include <arpa/inet.h>
+
+#include "qemu-thread.h"
+#include "qemu-common.h"
+
+#include "vscard_common.h"
+
+#include "vreader.h"
+#include "vcard_emul.h"
+#include "vevent.h"
+
+int verbose;
+
+int sock;
+
+static void
+print_byte_array(
+    uint8_t *arrBytes,
+    unsigned int nSize
+) {
+    int i;
+    for (i = 0; i < nSize; i++) {
+        printf("%02X ", arrBytes[i]);
+    }
+    printf("\n");
+}
+
+static void
+print_usage(void) {
+    printf("vscclient [-c <certname> .. -e <emul_args> -d <level>%s] "
+            "<host> <port>\n",
+#ifdef USE_PASSTHRU
+    " -p");
+    printf(" -p use passthrough mode\n");
+#else
+   "");
+#endif
+    vcard_emul_usage();
+}
+
+static QemuMutex write_lock;
+
+static int
+send_msg(
+    VSCMsgType type,
+    uint32_t reader_id,
+    const void *msg,
+    unsigned int length
+) {
+    int rv;
+    VSCMsgHeader mhHeader;
+
+    qemu_mutex_lock(&write_lock);
+
+    if (verbose > 10) {
+        printf("sending type=%d id=%d, len =%d (0x%x)\n",
+               type, reader_id, length, length);
+    }
+
+    mhHeader.type = htonl(type);
+    mhHeader.reader_id = 0;
+    mhHeader.length = htonl(length);
+    rv = write(
+        sock,
+        &mhHeader,
+        sizeof(mhHeader)
+    );
+    if (rv < 0) {
+        /* Error */
+        printf("write header error\n");
+        close(sock);
+        qemu_mutex_unlock(&write_lock);
+        return 16;
+    }
+    rv = write(
+        sock,
+        msg,
+        length
+    );
+    if (rv < 0) {
+        /* Error */
+        printf("write error\n");
+        close(sock);
+        qemu_mutex_unlock(&write_lock);
+        return 16;
+    }
+    qemu_mutex_unlock(&write_lock);
+
+    return 0;
+}
+
+static VReader *pending_reader;
+static QemuMutex pending_reader_lock;
+static QemuCond pending_reader_condition;
+
+#define MAX_ATR_LEN 40
+static void *
+event_thread(void *arg)
+{
+    unsigned char atr[MAX_ATR_LEN];
+    int atr_len = MAX_ATR_LEN;
+    VEvent *event = NULL;
+    unsigned int reader_id;
+
+
+    while (1) {
+        const char *reader_name;
+
+        event = vevent_wait_next_vevent();
+        if (event == NULL) {
+            break;
+        }
+        reader_id = vreader_get_id(event->reader);
+        if (reader_id == VSCARD_UNDEFINED_READER_ID &&
+            event->type != VEVENT_READER_INSERT) {
+            /* ignore events from readers qemu has rejected */
+            /* if qemu is still deciding on this reader, wait to see if need to
+             * forward this event */
+            qemu_mutex_lock(&pending_reader_lock);
+            if (!pending_reader || (pending_reader != event->reader)) {
+                /* wasn't for a pending reader, this reader has already been
+                 * rejected by qemu */
+                qemu_mutex_unlock(&pending_reader_lock);
+                vevent_delete(event);
+                continue;
+            }
+            /* this reader hasn't been told it's status from qemu yet, wait for
+             * that status */
+            while (pending_reader != NULL) {
+                qemu_cond_wait(&pending_reader_condition, &pending_reader_lock);
+            }
+            qemu_mutex_unlock(&pending_reader_lock);
+            /* now recheck the id */
+            reader_id = vreader_get_id(event->reader);
+            if (reader_id == VSCARD_UNDEFINED_READER_ID) {
+                /* this reader was rejected */
+                vevent_delete(event);
+                continue;
+            }
+            /* reader was accepted, now forward the event */
+        }
+        switch (event->type) {
+        case VEVENT_READER_INSERT:
+            /* tell qemu to insert a new CCID reader */
+            /* wait until qemu has responded to our first reader insert
+             * before we send a second. That way we won't confuse the responses
+             * */
+            qemu_mutex_lock(&pending_reader_lock);
+            while (pending_reader != NULL) {
+                qemu_cond_wait(&pending_reader_condition, &pending_reader_lock);
+            }
+            pending_reader = vreader_reference(event->reader);
+            qemu_mutex_unlock(&pending_reader_lock);
+            reader_name = vreader_get_name(event->reader);
+            if (verbose > 10) {
+                printf(" READER INSERT: %s\n", reader_name);
+            }
+            send_msg(
+                VSC_ReaderAdd,
+                reader_id, /* currerntly VSCARD_UNDEFINED_READER_ID */
+                NULL, 0
+                /*reader_name,
+                strlen(reader_name) */
+            );
+
+            break;
+        case VEVENT_READER_REMOVE:
+            /* future, tell qemu that an old CCID reader has been removed */
+            if (verbose > 10) {
+                printf(" READER REMOVE: %d\n", reader_id);
+            }
+            send_msg(
+                VSC_ReaderRemove,
+                reader_id,
+                NULL,
+                0
+            );
+            break;
+        case VEVENT_CARD_INSERT:
+            /* get the ATR (intended as a response to a power on from the
+             * reader */
+            atr_len = MAX_ATR_LEN;
+            vreader_power_on(event->reader, atr, &atr_len);
+            /* ATR call functions as a Card Insert event */
+            if (verbose > 10) {
+                printf(" CARD INSERT %d: ", reader_id);
+                print_byte_array(atr, atr_len);
+            }
+            send_msg(
+                VSC_ATR,
+                reader_id,
+                atr,
+                atr_len
+            );
+            break;
+        case VEVENT_CARD_REMOVE:
+            /* Card removed */
+            if (verbose > 10) {
+                printf(" CARD REMOVE %d:\n", reader_id);
+            }
+            send_msg(
+                VSC_CardRemove,
+                reader_id,
+                NULL,
+                0
+            );
+            break;
+        default:
+            break;
+        }
+        vevent_delete(event);
+    }
+    return NULL;
+}
+
+
+static unsigned int
+get_id_from_string(char *string, unsigned int default_id)
+{
+    unsigned int id = atoi(string);
+
+    /* don't accidentally swith to zero because no numbers have been supplied */
+    if ((id == 0) && *string != '0') {
+        return default_id;
+    }
+    return id;
+}
+
+static void
+do_command(void)
+{
+    char inbuf[255];
+    char *string;
+    VCardEmulError error;
+    static unsigned int default_reader_id;
+    unsigned int reader_id;
+    VReader *reader = NULL;
+
+    reader_id = default_reader_id;
+    string = fgets(inbuf, sizeof(inbuf), stdin);
+    if (string != NULL) {
+        if (strncmp(string, "exit", 4) == 0) {
+            /* remove all the readers */
+            VReaderList *list = vreader_get_reader_list();
+            VReaderListEntry *reader_entry;
+            printf("Active Readers:\n");
+            for (reader_entry = vreader_list_get_first(list); reader_entry;
+                 reader_entry = vreader_list_get_next(reader_entry)) {
+                VReader *reader = vreader_list_get_reader(reader_entry);
+                vreader_id_t reader_id;
+                reader_id = vreader_get_id(reader);
+                if (reader_id == -1) {
+                    continue;
+                }
+                /* be nice and signal card removal first (qemu probably should
+                 * do this itself) */
+                if (vreader_card_is_present(reader) == VREADER_OK) {
+                    send_msg(
+                        VSC_CardRemove,
+                        reader_id,
+                        NULL,
+                        0
+                    );
+                }
+                send_msg(
+                    VSC_ReaderRemove,
+                    reader_id,
+                    NULL,
+                    0
+                );
+            }
+            exit(0);
+        } else if (strncmp(string, "insert", 6) == 0) {
+            if (string[6] == ' ') {
+                reader_id = get_id_from_string(&string[7], reader_id);
+            }
+            reader = vreader_get_reader_by_id(reader_id);
+            if (reader != NULL) {
+                error = vcard_emul_force_card_insert(reader);
+                printf("insert %s, returned %d\n",
+                       reader ? vreader_get_name(reader)
+                       : "invalid reader", error);
+            } else {
+                printf("no reader by id %d found\n", reader_id);
+            }
+        } else if (strncmp(string, "remove", 6) == 0) {
+            if (string[6] == ' ') {
+                reader_id = get_id_from_string(&string[7], reader_id);
+            }
+            reader = vreader_get_reader_by_id(reader_id);
+            if (reader != NULL) {
+                error = vcard_emul_force_card_remove(reader);
+                printf("remove %s, returned %d\n",
+                        reader ? vreader_get_name(reader)
+                        : "invalid reader", error);
+            } else {
+                printf("no reader by id %d found\n", reader_id);
+            }
+        } else if (strncmp(string, "select", 6) == 0) {
+            if (string[6] == ' ') {
+                reader_id = get_id_from_string(&string[7],
+                                               VSCARD_UNDEFINED_READER_ID);
+            }
+            if (reader_id != VSCARD_UNDEFINED_READER_ID) {
+                reader = vreader_get_reader_by_id(reader_id);
+            }
+            if (reader) {
+                printf("Selecting reader %d, %s\n", reader_id,
+                        vreader_get_name(reader));
+                default_reader_id = reader_id;
+            } else {
+                printf("Reader with id %d not found\n", reader_id);
+            }
+        } else if (strncmp(string, "debug", 5) == 0) {
+            if (string[5] == ' ') {
+                verbose = get_id_from_string(&string[6], 0);
+            }
+            printf("debug level = %d\n", verbose);
+        } else if (strncmp(string, "list", 4) == 0) {
+            VReaderList *list = vreader_get_reader_list();
+            VReaderListEntry *reader_entry;
+            printf("Active Readers:\n");
+            for (reader_entry = vreader_list_get_first(list); reader_entry;
+                 reader_entry = vreader_list_get_next(reader_entry)) {
+                VReader *reader = vreader_list_get_reader(reader_entry);
+                vreader_id_t reader_id;
+                reader_id = vreader_get_id(reader);
+                if (reader_id == -1) {
+                    continue;
+                }
+                printf("%3d %s %s\n", reader_id,
+                       vreader_card_is_present(reader) == VREADER_OK ?
+                       "CARD_PRESENT" : "            ",
+                       vreader_get_name(reader));
+            }
+            printf("Inactive Readers:\n");
+            for (reader_entry = vreader_list_get_first(list); reader_entry;
+                 reader_entry = vreader_list_get_next(reader_entry)) {
+                VReader *reader = vreader_list_get_reader(reader_entry);
+                vreader_id_t reader_id;
+                reader_id = vreader_get_id(reader);
+                if (reader_id != -1) {
+                    continue;
+                }
+
+                printf("INA %s %s\n",
+                       vreader_card_is_present(reader) == VREADER_OK ?
+                       "CARD_PRESENT" : "            ",
+                       vreader_get_name(reader));
+            }
+        } else if (*string != 0) {
+            printf("valid commands:\n");
+            printf("insert [reader_id]\n");
+            printf("remove [reader_id]\n");
+            printf("select reader_id\n");
+            printf("list\n");
+            printf("debug [level]\n");
+            printf("exit\n");
+        }
+    }
+    vreader_free(reader);
+    printf("> ");
+    fflush(stdout);
+}
+
+
+#define APDUBufSize 270
+
+/* just for ease of parsing command line arguments. */
+#define MAX_CERTS 100
+
+static int
+connect_to_qemu(
+    const char *host,
+    const char *port
+) {
+    struct addrinfo hints;
+    struct addrinfo *server;
+    int ret;
+
+    sock = socket(
+        AF_INET,
+        SOCK_STREAM,
+        0
+    );
+    if (sock < 0) {
+        /* Error */
+        printf("Error opening socket!\n");
+    }
+
+    memset(&hints, 0, sizeof(struct addrinfo));
+    hints.ai_family = AF_UNSPEC;
+    hints.ai_socktype = SOCK_STREAM;
+    hints.ai_flags = 0;
+    hints.ai_protocol = 0;          /* Any protocol */
+
+    ret = getaddrinfo(host, port, &hints, &server);
+
+    if (ret != 0) {
+        printf("getaddrinfo failed\n");
+        return 5;
+    }
+
+    if (connect(
+            sock,
+            server->ai_addr,
+            server->ai_addrlen
+        ) < 0
+    ) {
+        /* Error */
+        printf("Could not connect\n");
+        return 5;
+    }
+    if (verbose) {
+        printf("Connected (sizeof Header=%zd)!\n", sizeof(VSCMsgHeader));
+    }
+    return sock;
+}
+
+static int on_host_init(VSCMsgHeader *mhHeader, VSCMsgInit *incoming)
+{
+    uint32_t *capabilities = (incoming->capabilities);
+    int num_capabilities =
+        1 + ((mhHeader->length - sizeof(VSCMsgInit)) / sizeof(uint32_t));
+    int i;
+    int rv;
+    pthread_t thread_id;
+
+    incoming->version = ntohl(incoming->version);
+    if (incoming->version != VSCARD_VERSION) {
+        if (verbose > 0) {
+            printf("warning: host has version %d, we have %d\n",
+                verbose, VSCARD_VERSION);
+        }
+    }
+    if (incoming->magic != VSCARD_MAGIC) {
+        printf("unexpected magic: got %d, expected %d\n",
+            incoming->magic, VSCARD_MAGIC);
+        return -1;
+    }
+    for (i = 0 ; i < num_capabilities; ++i) {
+        capabilities[i] = ntohl(capabilities[i]);
+    }
+    /* Future: check capabilities */
+    /* remove whatever reader might be left in qemu,
+     * in case of an unclean previous exit. */
+    send_msg(
+        VSC_ReaderRemove,
+        VSCARD_MINIMAL_READER_ID,
+        NULL,
+        0
+    );
+    /* launch the event_thread. This will trigger reader adds for all the
+     * existing readers */
+    rv = pthread_create(&thread_id, NULL, event_thread, NULL);
+    if (rv < 0) {
+        perror("pthread_create");
+        return rv;
+    }
+    return 0;
+}
+
+int
+main(
+    int argc,
+    char *argv[]
+) {
+    char *qemu_host;
+    char *qemu_port;
+    VSCMsgHeader mhHeader;
+    VSCMsgError *error_msg;
+
+    int rv;
+    int dwSendLength;
+    int dwRecvLength;
+    uint8_t pbRecvBuffer[APDUBufSize];
+    uint8_t pbSendBuffer[APDUBufSize];
+     VReaderStatus reader_status;
+    VReader *reader = NULL;
+    VCardEmulOptions *command_line_options = NULL;
+
+    char *cert_names[MAX_CERTS];
+    char *emul_args = NULL;
+    int cert_count = 0;
+    int c;
+
+    while ((c = getopt(argc, argv, "c:e:pd:")) != -1) {
+        switch (c) {
+        case 'c':
+            if (cert_count >= MAX_CERTS) {
+                printf("too many certificates (max = %d)\n", MAX_CERTS);
+                exit(5);
+            }
+            cert_names[cert_count++] = optarg;
+            break;
+        case 'e':
+            emul_args = optarg;
+            break;
+        case 'p':
+            print_usage();
+            exit(4);
+            break;
+        case 'd':
+            verbose = get_id_from_string(optarg, 1);
+            break;
+        }
+    }
+
+    if (argc - optind != 2) {
+        print_usage();
+        exit(4);
+    }
+
+    if (cert_count > 0) {
+        char *new_args;
+        int len, i;
+        /* if we've given some -c options, we clearly we want do so some
+         * software emulation.  add that emulation now. this is NSS Emulator
+         * specific */
+        if (emul_args == NULL) {
+            emul_args = (char *)"db=\"/etc/pki/nssdb\"";
+        }
+#define SOFT_STRING ",soft=(,Virtual Reader,CAC,,"
+             /* 2 == close paren & null */
+        len = strlen(emul_args) + strlen(SOFT_STRING) + 2;
+        for (i = 0; i < cert_count; i++) {
+            len += strlen(cert_names[i])+1; /* 1 == comma */
+        }
+        new_args = qemu_malloc(len);
+        strcpy(new_args, emul_args);
+        strcat(new_args, SOFT_STRING);
+        for (i = 0; i < cert_count; i++) {
+            strcat(new_args, cert_names[i]);
+            strcat(new_args, ",");
+        }
+        strcat(new_args, ")");
+        emul_args = new_args;
+    }
+    if (emul_args) {
+        command_line_options = vcard_emul_options(emul_args);
+    }
+
+    qemu_host = strdup(argv[argc - 2]);
+    qemu_port = strdup(argv[argc - 1]);
+    sock = connect_to_qemu(qemu_host, qemu_port);
+
+    qemu_mutex_init(&write_lock);
+    qemu_mutex_init(&pending_reader_lock);
+    qemu_cond_init(&pending_reader_condition);
+
+    vcard_emul_init(command_line_options);
+
+    printf("> ");
+    fflush(stdout);
+
+    /* Send init message, Host responds (and then we send reader attachments) */
+    VSCMsgInit init = {
+        .version = htonl(VSCARD_VERSION),
+        .magic = VSCARD_MAGIC,
+        .capabilities = {0}
+    };
+    send_msg(VSC_Init, mhHeader.reader_id, &init, sizeof(init));
+
+    do {
+        fd_set fds;
+
+        FD_ZERO(&fds);
+        FD_SET(1, &fds);
+        FD_SET(sock, &fds);
+
+        /* waiting on input from the socket */
+        rv = select(sock+1, &fds, NULL, NULL, NULL);
+        if (rv < 0) {
+            /* handle error */
+            perror("select");
+            return 7;
+        }
+        if (FD_ISSET(1, &fds)) {
+            do_command();
+        }
+        if (!FD_ISSET(sock, &fds)) {
+            continue;
+        }
+
+        rv = read(
+            sock,
+            &mhHeader,
+            sizeof(mhHeader)
+        );
+        if (rv < sizeof(mhHeader)) {
+            /* Error */
+            if (rv < 0) {
+                perror("header read error\n");
+            } else {
+                printf("header short read %d\n", rv);
+            }
+            return 8;
+        }
+        mhHeader.type = ntohl(mhHeader.type);
+        mhHeader.reader_id = ntohl(mhHeader.reader_id);
+        mhHeader.length = ntohl(mhHeader.length);
+        if (verbose) {
+            printf("Header: type=%d, reader_id=%d length=%d (0x%x)\n",
+                    mhHeader.type, mhHeader.reader_id, mhHeader.length,
+                                               mhHeader.length);
+        }
+        switch (mhHeader.type) {
+        case VSC_APDU:
+        case VSC_Flush:
+        case VSC_Error:
+        case VSC_Init:
+            rv = read(
+                sock,
+                pbSendBuffer,
+                mhHeader.length
+            );
+            break;
+        default:
+            printf("Unexpected message of type 0x%X\n", mhHeader.type);
+            return 0;
+        }
+        switch (mhHeader.type) {
+        case VSC_APDU:
+            if (rv < 0) {
+                /* Error */
+                printf("read error\n");
+                close(sock);
+                return 8;
+            }
+            if (verbose) {
+                printf(" recv APDU: ");
+                print_byte_array(pbSendBuffer, mhHeader.length);
+            }
+            /* Transmit recieved APDU */
+            dwSendLength = mhHeader.length;
+            dwRecvLength = sizeof(pbRecvBuffer);
+            reader = vreader_get_reader_by_id(mhHeader.reader_id);
+            reader_status = vreader_xfr_bytes(reader,
+                pbSendBuffer, dwSendLength,
+                pbRecvBuffer, &dwRecvLength);
+            if (reader_status == VREADER_OK) {
+                mhHeader.length = dwRecvLength;
+                if (verbose) {
+                    printf(" send response: ");
+                    print_byte_array(pbRecvBuffer, mhHeader.length);
+                }
+                send_msg(
+                    VSC_APDU,
+                    mhHeader.reader_id,
+                    pbRecvBuffer,
+                    dwRecvLength
+                );
+            } else {
+                rv = reader_status; /* warning: not meaningful */
+                send_msg(
+                    VSC_Error,
+                    mhHeader.reader_id,
+                    &rv,
+                    sizeof(uint32_t)
+                );
+            }
+            vreader_free(reader);
+            reader = NULL; /* we've freed it, don't use it by accident
+                              again */
+            break;
+        case VSC_Flush:
+            /* TODO: actually flush */
+            send_msg(VSC_FlushComplete, mhHeader.reader_id, NULL, 0);
+            break;
+        case VSC_Error:
+            error_msg = (VSCMsgError *) pbSendBuffer;
+            if (error_msg->code == VSC_SUCCESS) {
+                qemu_mutex_lock(&pending_reader_lock);
+                if (pending_reader) {
+                    vreader_set_id(pending_reader, mhHeader.reader_id);
+                    vreader_free(pending_reader);
+                    pending_reader = NULL;
+                    qemu_cond_signal(&pending_reader_condition);
+                }
+                qemu_mutex_unlock(&pending_reader_lock);
+                break;
+            }
+            printf("error: qemu refused to add reader\n");
+            if (error_msg->code == VSC_CANNOT_ADD_MORE_READERS) {
+                /* clear pending reader, qemu can't handle any more */
+                qemu_mutex_lock(&pending_reader_lock);
+                if (pending_reader) {
+                    pending_reader = NULL;
+                    /* make sure the event loop doesn't hang */
+                    qemu_cond_signal(&pending_reader_condition);
+                }
+                qemu_mutex_unlock(&pending_reader_lock);
+            }
+            break;
+        case VSC_Init:
+            if (on_host_init(&mhHeader, (VSCMsgInit *)pbSendBuffer) < 0) {
+                return -1;
+            }
+            break;
+        default:
+            printf("Default\n");
+            return 0;
+        }
+    } while (rv >= 0);
+
+
+    return 0;
+}