Changing configuration structure to enable multiple accounts.

This change enables using multiple wire plugins at the same time.
Also, we now distinguish between the wire plugin (i.e. EBICS or
taler_bank) and the wire method (i.e. SEPA or x-taler-bank) that
the wire plugin is implementing.  The "taler-bank" wire method
was renamed from "test" to "x-taler-bank".

This also changes the format of the /wire response of the exchange,
as we now need to return multiple accounts.  Note that wire fees
are specified per wire method, not per wire account.

taler-exchange-keyup now automatically signs all of the /wire
responses in the location specified by the configuration.

Account identification in wire plugins was changed to use
payto://-URLs instead of method-specific JSON fields.  Signing
and validation of /wire responses was moved from each wire
plugin to a generic validation method in libtalerutil (crypto)
or libtalerjson (for JSON-formatted inputs).
Convenience methods were added to generate JSON for wire accounts
(salting, signing).

Various section and option names were adjusted to streamline the
configuration and make it more consistent overall.  Documentation
was updated as well.

1 files changed, 57 insertions, 0 deletions

diff --git a/src/wire/wire_helper.c b/src/wire/wire_helper.c
new file mode 100644
index 000000000..34d40e11e
--- /dev/null
+++ b/src/wire/wire_helper.c
@@ -0,0 +1,57 @@
+/*
+  This file is part of TALER
+  (C) 2018 Taler Systems SA
+
+  TALER is free software; you can redistribute it and/or modify it under the
+  terms of the GNU General Public License as published by the Free Software
+  Foundation; either version 3, or (at your option) any later version.
+
+  TALER is distributed in the hope that it will be useful, but WITHOUT ANY
+  WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR
+  A PARTICULAR PURPOSE.  See the GNU General Public License for more details.
+
+  You should have received a copy of the GNU General Public License along with
+  TALER; see the file COPYING.  If not, see <http://www.gnu.org/licenses/>
+*/
+
+/**
+ * @file wire/wire_helper.c
+ * @brief Helper functions for dealing with wire formats
+ * @author Christian Grothoff <christian@grothoff.org>
+ */
+#include "platform.h"
+#include "taler_util.h"
+#include "taler_wire_lib.h"
+
+/**
+ * Prefix of PAYTO URLs.
+ */
+#define PAYTO "payto://"
+
+
+/**
+ * Obtain the payment method from a @a payto_url
+ *
+ * @param payto_url the URL to parse
+ * @return NULL on error (malformed @a payto_url)
+ */
+char *
+TALER_WIRE_payto_get_method (const char *payto_url)
+{
+  const char *start;
+  const char *end;
+
+  if (0 != strncmp (payto_url,
+                    PAYTO,
+                    strlen (PAYTO)))
+    return NULL;
+  start = &payto_url[strlen(PAYTO)];
+  end = strchr (start,
+                (unsigned char) '/');
+  if (NULL == end)
+    return NULL;
+  return GNUNET_strndup (start,
+                         end - start);
+}
+
+/* end of wire_helper.c */