/* ------------------
* sign a plain string with the key found with fingerprint fpr
* FREE MEMORY AFTER USAGE OF RETURN VALUE!
* ------------------ */
static char* sign(const char* plain_str,const char* fpr)
{
gpgme_error_t error;
gpgme_ctx_t ctx;
gpgme_key_t key;
gpgme_data_t plain,sig;
const int MAX_LEN = 10000;
char *sig_str = NULL;
char *sig_str_dup = NULL;
size_t len = 0;
// connect to gpgme
gpgme_check_version (NULL);
error = gpgme_new(&ctx);
if (error)
{
purple_debug_error(PLUGIN_ID,"gpgme_new failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
return NULL;
}
// get key by fingerprint
error = gpgme_get_key(ctx,fpr,&key,1);
if (error || !key)
{
purple_debug_error(PLUGIN_ID,"gpgme_get_key failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
gpgme_release (ctx);
return NULL;
}
// select signers
gpgme_signers_clear(ctx);
error = gpgme_signers_add (ctx,key);
if (error)
{
purple_debug_error(PLUGIN_ID,"gpgme_signers_add failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
gpgme_release (ctx);
return NULL;
}
// create data containers
gpgme_data_new_from_mem (&plain, plain_str,strlen(plain_str),1);
gpgme_data_new(&sig);
// sign message, ascii armored
gpgme_set_armor(ctx,1);
error = gpgme_op_sign(ctx,plain,sig,GPGME_SIG_MODE_DETACH);
if (error)
{
purple_debug_error(PLUGIN_ID,"gpgme_op_sign failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
gpgme_release (ctx);
return NULL;
}
// release memory for data containers
gpgme_data_release(plain);
sig_str = gpgme_data_release_and_get_mem(sig,&len);
if (sig_str != NULL)
{
sig_str[len] = 0;
sig_str_dup = str_unarmor(sig_str);
}
gpgme_free(sig_str);
// close gpgme connection
gpgme_release (ctx);
return sig_str_dup;
}
/* ------------------
* encrypt a plain string with the key found with fingerprint fpr
* ------------------ */
static char* encrypt(const char* plain_str, const char* fpr)
{
gpgme_error_t error;
gpgme_ctx_t ctx;
gpgme_key_t key;
gpgme_data_t plain,cipher;
char* cipher_str = NULL;
char* cipher_str_dup = NULL;
size_t len;
gpgme_key_t key_arr[2];
key_arr[0] = NULL;
key_arr[1] = NULL;
// connect to gpgme
gpgme_check_version (NULL);
error = gpgme_new(&ctx);
if (error)
{
purple_debug_error(PLUGIN_ID,"gpgme_new failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
return NULL;
}
// get key by fingerprint
error = gpgme_get_key(ctx,fpr,&key,0);
if (error || !key)
{
purple_debug_error(PLUGIN_ID,"gpgme_get_key failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
gpgme_release (ctx);
return NULL;
}
key_arr[0] = key;
// create data containers
gpgme_data_new_from_mem (&plain, plain_str,strlen(plain_str),1);
gpgme_data_new(&cipher);
// encrypt, ascii armored
gpgme_set_armor(ctx,1);
error = gpgme_op_encrypt (ctx, key_arr,GPGME_ENCRYPT_ALWAYS_TRUST,plain,cipher);
if (error)
{
purple_debug_error(PLUGIN_ID,"gpgme_op_encrypt failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
gpgme_release (ctx);
return NULL;
}
// release memory for data containers
gpgme_data_release(plain);
cipher_str = gpgme_data_release_and_get_mem(cipher,&len);
if (cipher_str != NULL)
{
cipher_str_dup = str_unarmor(cipher_str);
}
gpgme_free(cipher_str);
// close gpgme connection
gpgme_release (ctx);
return cipher_str_dup;
}
/* ------------------
* encrypt a plain string with the key found with fingerprint fpr
* ------------------ */
static char* encrypt(const char* plain_str, const char* fpr)
{
gpgme_error_t error;
gpgme_ctx_t ctx;
gpgme_key_t key;
gpgme_key_t sender_key;
gpgme_data_t plain,cipher;
char* cipher_str = NULL;
char* cipher_str_dup = NULL;
size_t len;
gpgme_key_t key_arr[3];
key_arr[0] = NULL;
key_arr[1] = NULL;
key_arr[2] = NULL;
// connect to gpgme
gpgme_check_version (NULL);
error = gpgme_new(&ctx);
if (error)
{
purple_debug_error(PLUGIN_ID,"gpgme_new failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
return NULL;
}
// get key by fingerprint
error = gpgme_get_key(ctx,fpr,&key,0);
if (error || !key)
{
purple_debug_error(PLUGIN_ID,"gpgme_get_key failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
gpgme_release (ctx);
return NULL;
}
key_arr[0] = key;
// check if user selected a main key
const char* sender_fpr = purple_prefs_get_string(PREF_MY_KEY);
if ( sender_fpr != NULL && strcmp(sender_fpr,"") != 0)
{
// get own key by fingerprint
error = gpgme_get_key(ctx,sender_fpr,&sender_key,0);
if (!error && sender_key)
key_arr[1] = sender_key;
else
purple_debug_error(PLUGIN_ID,"gpgme_get_key: sender key for fingerprint %s is missing! error: %s %s\n", sender_fpr, gpgme_strsource (error), gpgme_strerror (error) );
}
else
purple_debug_error(PLUGIN_ID,"purple_prefs_get_string: PREF_MY_KEY was empty\n");
// create data containers
gpgme_data_new_from_mem (&plain, plain_str,strlen(plain_str),1);
gpgme_data_new(&cipher);
// encrypt, ascii armored
gpgme_set_armor(ctx,1);
error = gpgme_op_encrypt (ctx, key_arr,GPGME_ENCRYPT_ALWAYS_TRUST,plain,cipher);
if (error)
{
purple_debug_error(PLUGIN_ID,"gpgme_op_encrypt failed: %s %s\n",gpgme_strsource (error), gpgme_strerror (error));
gpgme_release (ctx);
return NULL;
}
// release memory for data containers
gpgme_data_release(plain);
cipher_str = gpgme_data_release_and_get_mem(cipher,&len);
if (cipher_str != NULL)
{
cipher_str_dup = str_unarmor(cipher_str);
}
gpgme_free(cipher_str);
// close gpgme connection
gpgme_release (ctx);
return cipher_str_dup;
}
