Getting junk data while storing and accessing key

Question

I need some directions on the following. Please guide me through it:

Objective: To store and access file encryption keys for a given user. Each file will have a separate encryption key. So, a user who wants to encrypt 10 files will have 10 different keys stored on the keyring.

Issue: I am facing two issues: 1. Getting junk data while storing and accessing keys 2. Callback function is not being called

Implementation:

#include <stdio.h>
#include <gnome-keyring-1/gnome-keyring.h>
#include <gnome-keyring-1/gnome-keyring-memory.h>

GnomeKeyringPasswordSchema my_schema = {
    GNOME_KEYRING_ITEM_GENERIC_SECRET,
    {
        { "user", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
        { "file", GNOME_KEYRING_ATTRIBUTE_TYPE_STRING },
        { NULL, 0 }
    }
};

void
stored_password (GnomeKeyringResult res, gpointer user_data)
{
    printf( "DEBUG: StoredPass - BFR\n" );

        /* user_data will be the same as was passed to gnome_keyring_store_password() */
        if (res == GNOME_KEYRING_RESULT_OK)
                printf ("password saved successfully!\n");
        else
                printf ("couldn't save password: %s", gnome_keyring_result_to_message (res));

    printf( "DEBUG: StoredPass - AFR\n" );
}

void
save_my_password()
{
    GnomeKeyringResult res;
    gpointer gp = NULL, gp2 = NULL;

    printf( "DEBUG: SaveMyPass - BFR\n" );

        gp = gnome_keyring_store_password ( &my_schema,         /* The password type */
                                          GNOME_KEYRING_DEFAULT,          /* Where to save it */
                                          "My file encryption password",    /* Password description, displayed to user */
                                          "test1000",                     /* The password itself */
                                          stored_password,                /* A function called when complete */
                                          gp2, NULL,                        /* User data for callback, and destroy notify */

                                          /* Attributes */
                                          "user", "piyush",
                    "file", "abc.txt",
                                          NULL);                 /* Always end with NULL */

    printf( "DEBUG: SaveMyPass - AFR\n" );

    g_assert( gp != NULL );
    printf( "%p %s\n", gp, (char *)gp );
}

/* A callback called when the operation completes */
void
found_password (GnomeKeyringResult res, const gchar* password, gpointer user_data)
{
        /* user_data will be the same as was passed to gnome_keyring_find_password() */
    printf( "DEBUG: FoundPass - BFR\n" );

        if (res == GNOME_KEYRING_RESULT_OK)
                printf ("password found was: %s\n", password);
        else
                printf ("couldn't find password: %s", gnome_keyring_result_to_message (res));

        /* Once this function returns |password| will be freed */
    printf( "DEBUG: FoundPass - AFR\n" );
}

void
find_my_password()
{
    printf( "DEBUG: FindMyPass - BFR\n" );

        gpointer gp = gnome_keyring_find_password ( &my_schema,      /* The password type */
                                         found_password,                 /* A function called when complete */
                                         NULL, NULL,                     /* User data for callback, and destroy notify */

                                          /* Attributes */
                                          "user", "piyush", 
                                          "file", "abc.txt",
                                     NULL);                 /* Always end with NULL */

    printf( "DEBUG: FindMyPass - AFR\n" );
    g_assert( gp != NULL );
    printf( "%p %s\n", gp, (char *)gp );
}

int main() {
    save_my_password();
    find_my_password();
}

Compile: gcc gnomekey.c -o gnomekey -lgnome-keyring pkg-config --cflags --libs gnome-keyring-1

Output: ./gnomekey

DEBUG: SaveMyPass - BFR
DEBUG: SaveMyPass - AFR
0x8676800 <junk-data>
DEBUG: FindMyPass - BFR
DEBUG: FindMyPass - AFR
0x8676828 <junk-data>

score 1 · Answer 1 · answered Nov 21 '11 at 06:24

It looks like you're using the asynchronous API for gnome-keyring. These APIs rely on the glib event loop running to receive the replies from the keyring daemon.

Your application does not appear to be running the event loop, and exits before the responses to your keyring daemon requests can be answered, which would explain the problems you've seen.

There are two ways you could fix this problem:

Modify your application to run the main loop so that it can receive the responses.
Use the synchronous versions of the APIs (i.e. gnome_keyring_store_password_sync and gnome_keyring_find_password_sync), so the library calls block waiting for responses instead.

If you are writing a graphical application you're probably already doing (1), so you're using the right API. It might just be a case of modifying your test programs to also run the main loop.

If you are writing a command line script then blocking behaviour is probably not a big issue, so using the synchronous API will make your life a lot easier.

Getting junk data while storing and accessing key

1 Answers1