summaryrefslogtreecommitdiff
path: root/src/mint-lib/mint_api_refresh.c
diff options
context:
space:
mode:
Diffstat (limited to 'src/mint-lib/mint_api_refresh.c')
-rw-r--r--src/mint-lib/mint_api_refresh.c540
1 files changed, 540 insertions, 0 deletions
diff --git a/src/mint-lib/mint_api_refresh.c b/src/mint-lib/mint_api_refresh.c
new file mode 100644
index 00000000..723fe707
--- /dev/null
+++ b/src/mint-lib/mint_api_refresh.c
@@ -0,0 +1,540 @@
+/*
+ This file is part of TALER
+ Copyright (C) 2015 Christian Grothoff (and other contributing authors)
+
+ 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, If not, see
+ <http://www.gnu.org/licenses/>
+*/
+/**
+ * @file mint-lib/mint_api_refresh.c
+ * @brief Implementation of the /refresh/melt+reveal requests of the mint's HTTP API
+ * @author Christian Grothoff
+ */
+#include "platform.h"
+#include <curl/curl.h>
+#include <jansson.h>
+#include <microhttpd.h> /* just for HTTP status codes */
+#include <gnunet/gnunet_util_lib.h>
+#include "taler_mint_service.h"
+#include "mint_api_json.h"
+#include "mint_api_context.h"
+#include "mint_api_handle.h"
+#include "taler_signatures.h"
+
+
+/* ********************* /refresh/ common ***************************** */
+
+
+/**
+ * Melt (partially spent) coins to obtain fresh coins that are
+ * unlinkable to the original coin(s). Note that melting more
+ * than one coin in a single request will make those coins linkable,
+ * so the safest operation only melts one coin at a time.
+ *
+ * This API is typically used by a wallet. Note that to ensure that
+ * no money is lost in case of hardware failures, is operation does
+ * not actually initiate the request. Instead, it generates a buffer
+ * which the caller must store before proceeding with the actual call
+ * to #TALER_MINT_refresh_execute() that will generate the request.
+ *
+ * This function does verify that the given request data is internally
+ * consistent. However, the @a melts_sigs are only verified if @a
+ * check_sigs is set to #GNUNET_YES, as this may be relatively
+ * expensive and should be redundant.
+ *
+ * Aside from some non-trivial cryptographic operations that might
+ * take a bit of CPU time to complete, this function returns
+ * its result immediately and does not start any asynchronous
+ * processing. This function is also thread-safe.
+ *
+ * @param num_melts number of coins that are being melted (typically 1)
+ * @param melt_privs array of @a num_melts private keys of the coins to melt
+ * @param melt_amounts array of @a num_melts amounts specifying how much
+ * each coin will contribute to the melt (including fee)
+ * @param melt_sigs array of @a num_melts signatures affirming the
+ * validity of the public keys corresponding to the
+ * @a melt_privs private keys
+ * @param melt_pks array of @a num_melts denomination key information
+ * records corresponding to the @a melt_sigs
+ * validity of the keys
+ * @param check_sigs verify the validity of the signatures of @a melt_sigs
+ * @param fresh_pks_len length of the @a pks array
+ * @param fresh_pks array of @a pks_len denominations of fresh coins to create
+ * @param[OUT] res_size set to the size of the return value, or 0 on error
+ * @return NULL
+ * if the inputs are invalid (i.e. denomination key not with this mint).
+ * Otherwise, pointer to a buffer of @a res_size to store persistently
+ * before proceeding to #TALER_MINT_refresh_execute().
+ * Non-null results should be freed using #GNUNET_free().
+ */
+char *
+TALER_MINT_refresh_prepare (unsigned int num_melts,
+ const struct TALER_CoinSpendPrivateKeyP *melt_privs,
+ const struct TALER_Amount *melt_amounts,
+ const struct TALER_DenominationSignature *melt_sigs,
+ const struct TALER_MINT_DenomPublicKey *melt_pks,
+ int check_sigs,
+ unsigned int fresh_pks_len,
+ const struct TALER_MINT_DenomPublicKey *fresh_pks,
+ size_t *res_size)
+{
+ GNUNET_break (0); // FIXME: not implemented
+ *res_size = 0;
+ return NULL;
+}
+
+
+/* ********************* /refresh/melt ***************************** */
+
+
+/**
+ * @brief A /refresh/melt Handle
+ */
+struct TALER_MINT_RefreshMeltHandle
+{
+
+ /**
+ * The connection to mint this request handle will use
+ */
+ struct TALER_MINT_Handle *mint;
+
+ /**
+ * The url for this request.
+ */
+ char *url;
+
+ /**
+ * JSON encoding of the request to POST.
+ */
+ char *json_enc;
+
+ /**
+ * Handle for the request.
+ */
+ struct MAC_Job *job;
+
+ /**
+ * Function to call with refresh melt failure results.
+ */
+ TALER_MINT_RefreshMeltCallback melt_cb;
+
+ /**
+ * Closure for @e result_cb and @e melt_failure_cb.
+ */
+ void *melt_cb_cls;
+
+ /**
+ * Download buffer
+ */
+ struct MAC_DownloadBuffer db;
+
+};
+
+
+/**
+ * Function called when we're done processing the
+ * HTTP /refresh/melt request.
+ *
+ * @param cls the `struct TALER_MINT_RefreshMeltHandle`
+ * @param eh the curl request handle
+ */
+static void
+handle_refresh_melt_finished (void *cls,
+ CURL *eh)
+{
+ struct TALER_MINT_RefreshMeltHandle *rmh = cls;
+ long response_code;
+ json_t *json;
+
+ rmh->job = NULL;
+ json = MAC_download_get_result (&rmh->db,
+ eh,
+ &response_code);
+ switch (response_code)
+ {
+ case 0:
+ break;
+ case MHD_HTTP_OK:
+ GNUNET_break (0); // FIXME: NOT implemented! (parse, check sig!)
+
+ break;
+ case MHD_HTTP_BAD_REQUEST:
+ /* This should never happen, either us or the mint is buggy
+ (or API version conflict); just pass JSON reply to the application */
+ break;
+ case MHD_HTTP_FORBIDDEN:
+ /* Double spending; check signatures on transaction history */
+ GNUNET_break (0); // FIXME: NOT implemented!
+ break;
+ case MHD_HTTP_UNAUTHORIZED:
+ /* Nothing really to verify, mint says one of the signatures is
+ invalid; assuming we checked them, this should never happen, we
+ should pass the JSON reply to the application */
+ break;
+ case MHD_HTTP_NOT_FOUND:
+ /* Nothing really to verify, this should never
+ happen, we should pass the JSON reply to the application */
+ break;
+ case MHD_HTTP_INTERNAL_SERVER_ERROR:
+ /* Server had an internal issue; we should retry, but this API
+ leaves this to the application */
+ break;
+ default:
+ /* unexpected response code */
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Unexpected response code %u\n",
+ response_code);
+ GNUNET_break (0);
+ response_code = 0;
+ break;
+ }
+ if (NULL != rmh->melt_cb)
+ rmh->melt_cb (rmh->melt_cb_cls,
+ response_code,
+ UINT16_MAX,
+ json);
+ json_decref (json);
+ TALER_MINT_refresh_melt_cancel (rmh);
+}
+
+
+/**
+ * Submit a melt request to the mint and get the mint's
+ * response.
+ *
+ * This API is typically used by a wallet. Note that to ensure that
+ * no money is lost in case of hardware failures, the provided
+ * argument should have been constructed using
+ * #TALER_MINT_refresh_prepare and committed to persistent storage
+ * prior to calling this function.
+ *
+ * @param mint the mint handle; the mint must be ready to operate
+ * @param refresh_data_length size of the @a refresh_data (returned
+ * in the `res_size` argument from #TALER_MINT_refresh_prepare())
+ * @param refresh_data the refresh data as returned from
+ #TALER_MINT_refresh_prepare())
+ * @param melt_cb the callback to call with the result
+ * @param melt_cb_cls closure for @a melt_cb
+ * @return a handle for this request; NULL if the argument was invalid.
+ * In this case, neither callback will be called.
+ */
+struct TALER_MINT_RefreshMeltHandle *
+TALER_MINT_refresh_melt (struct TALER_MINT_Handle *mint,
+ size_t refresh_data_length,
+ const char *refresh_data,
+ TALER_MINT_RefreshMeltCallback melt_cb,
+ void *melt_cb_cls)
+{
+ json_t *melt_obj;
+ struct TALER_MINT_RefreshMeltHandle *rmh;
+ CURL *eh;
+ struct TALER_MINT_Context *ctx;
+
+ if (GNUNET_YES !=
+ MAH_handle_is_ready (mint))
+ {
+ GNUNET_break (0);
+ return NULL;
+ }
+ /* FIXME: parse "refresh_data" */
+
+ /* FIXME: totally bogus request building here: */
+ melt_obj = json_pack ("{s:o, s:O}", /* f/wire */
+ "4", 42,
+ "6", 62);
+
+
+ rmh = GNUNET_new (struct TALER_MINT_RefreshMeltHandle);
+ rmh->mint = mint;
+ rmh->melt_cb = melt_cb;
+ rmh->melt_cb_cls = melt_cb_cls;
+
+ rmh->url = MAH_path_to_url (mint,
+ "/refresh/melt");
+
+ eh = curl_easy_init ();
+ GNUNET_assert (NULL != (rmh->json_enc =
+ json_dumps (melt_obj,
+ JSON_COMPACT)));
+ json_decref (melt_obj);
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_URL,
+ rmh->url));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_POSTFIELDS,
+ rmh->json_enc));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_POSTFIELDSIZE,
+ strlen (rmh->json_enc)));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_WRITEFUNCTION,
+ &MAC_download_cb));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_WRITEDATA,
+ &rmh->db));
+ ctx = MAH_handle_to_context (mint);
+ rmh->job = MAC_job_add (ctx,
+ eh,
+ GNUNET_YES,
+ &handle_refresh_melt_finished,
+ rmh);
+ return rmh;
+}
+
+
+/**
+ * Cancel a refresh execute request. This function cannot be used
+ * on a request handle if either callback was already invoked.
+ *
+ * @param rmh the refresh melt handle
+ */
+void
+TALER_MINT_refresh_melt_cancel (struct TALER_MINT_RefreshMeltHandle *rmh)
+{
+ if (NULL != rmh->job)
+ {
+ MAC_job_cancel (rmh->job);
+ rmh->job = NULL;
+ }
+ GNUNET_free_non_null (rmh->db.buf);
+ GNUNET_free (rmh->url);
+ GNUNET_free (rmh->json_enc);
+ GNUNET_free (rmh);
+}
+
+
+/* ********************* /refresh/reveal ***************************** */
+
+
+/**
+ * @brief A /refresh/reveal Handle
+ */
+struct TALER_MINT_RefreshRevealHandle
+{
+
+ /**
+ * The connection to mint this request handle will use
+ */
+ struct TALER_MINT_Handle *mint;
+
+ /**
+ * The url for this request.
+ */
+ char *url;
+
+ /**
+ * JSON encoding of the request to POST.
+ */
+ char *json_enc;
+
+ /**
+ * Handle for the request.
+ */
+ struct MAC_Job *job;
+
+ /**
+ * Function to call with the result.
+ */
+ TALER_MINT_RefreshRevealCallback reveal_cb;
+
+ /**
+ * Closure for @e reveal_cb.
+ */
+ void *reveal_cb_cls;
+
+ /**
+ * Download buffer
+ */
+ struct MAC_DownloadBuffer db;
+
+
+};
+
+
+/**
+ * Function called when we're done processing the
+ * HTTP /refresh/reveal request.
+ *
+ * @param cls the `struct TALER_MINT_RefreshHandle`
+ * @param eh the curl request handle
+ */
+static void
+handle_refresh_reveal_finished (void *cls,
+ CURL *eh)
+{
+ struct TALER_MINT_RefreshRevealHandle *rrh = cls;
+ long response_code;
+ json_t *json;
+
+ rrh->job = NULL;
+ json = MAC_download_get_result (&rrh->db,
+ eh,
+ &response_code);
+ switch (response_code)
+ {
+ case 0:
+ break;
+ case MHD_HTTP_OK:
+ GNUNET_break (0); // FIXME: NOT implemented!
+ // rrh->reveal_cb = NULL; (call with real result, do not call again below)
+ break;
+ case MHD_HTTP_BAD_REQUEST:
+ /* This should never happen, either us or the mint is buggy
+ (or API version conflict); just pass JSON reply to the application */
+ break;
+ case MHD_HTTP_CONFLICT:
+ /* Nothing really to verify, mint says our reveal is inconsitent
+ with our commitment, so either side is buggy; we
+ should pass the JSON reply to the application */
+ break;
+ case MHD_HTTP_INTERNAL_SERVER_ERROR:
+ /* Server had an internal issue; we should retry, but this API
+ leaves this to the application */
+ break;
+ default:
+ /* unexpected response code */
+ GNUNET_log (GNUNET_ERROR_TYPE_ERROR,
+ "Unexpected response code %u\n",
+ response_code);
+ GNUNET_break (0);
+ response_code = 0;
+ break;
+ }
+ if (NULL != rrh->reveal_cb)
+ rrh->reveal_cb (rrh->reveal_cb_cls,
+ response_code,
+ 0, NULL, NULL,
+ json);
+ json_decref (json);
+ TALER_MINT_refresh_reveal_cancel (rrh);
+}
+
+
+
+/**
+ * Submit a /refresh/reval request to the mint and get the mint's
+ * response.
+ *
+ * This API is typically used by a wallet. Note that to ensure that
+ * no money is lost in case of hardware failures, the provided
+ * arguments should have been committed to persistent storage
+ * prior to calling this function.
+ *
+ * @param mint the mint handle; the mint must be ready to operate
+ * @param refresh_data_length size of the @a refresh_data (returned
+ * in the `res_size` argument from #TALER_MINT_refresh_prepare())
+ * @param refresh_data the refresh data as returned from
+ #TALER_MINT_refresh_prepare())
+ * @param noreveal_index response from the mint to the
+ * #TALER_MINT_refresh_melt() invocation
+ * @param reveal_cb the callback to call with the final result of the
+ * refresh operation
+ * @param reveal_cb_cls closure for the above callback
+ * @return a handle for this request; NULL if the argument was invalid.
+ * In this case, neither callback will be called.
+ */
+struct TALER_MINT_RefreshRevealHandle *
+TALER_MINT_refresh_reveal (struct TALER_MINT_Handle *mint,
+ size_t refresh_data_length,
+ const char *refresh_data,
+ uint16_t noreveal_index,
+ TALER_MINT_RefreshRevealCallback reveal_cb,
+ void *reveal_cb_cls)
+{
+ struct TALER_MINT_RefreshRevealHandle *rrh;
+ json_t *reveal_obj;
+ CURL *eh;
+ struct TALER_MINT_Context *ctx;
+
+ if (GNUNET_YES !=
+ MAH_handle_is_ready (mint))
+ {
+ GNUNET_break (0);
+ return NULL;
+ }
+ /* FIXME: parse "refresh_data" */
+
+ /* FIXME: totally bogus request building here: */
+ reveal_obj = json_pack ("{s:o, s:O}", /* f/wire */
+ "4", 42,
+ "6", 62);
+
+ rrh = GNUNET_new (struct TALER_MINT_RefreshRevealHandle);
+ rrh->mint = mint;
+ rrh->reveal_cb = reveal_cb;
+ rrh->reveal_cb_cls = reveal_cb_cls;
+
+ rrh->url = MAH_path_to_url (rrh->mint,
+ "/refresh/reveal");
+
+ eh = curl_easy_init ();
+ GNUNET_assert (NULL != (rrh->json_enc =
+ json_dumps (reveal_obj,
+ JSON_COMPACT)));
+ json_decref (reveal_obj);
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_URL,
+ rrh->url));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_POSTFIELDS,
+ rrh->json_enc));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_POSTFIELDSIZE,
+ strlen (rrh->json_enc)));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_WRITEFUNCTION,
+ &MAC_download_cb));
+ GNUNET_assert (CURLE_OK ==
+ curl_easy_setopt (eh,
+ CURLOPT_WRITEDATA,
+ &rrh->db));
+ ctx = MAH_handle_to_context (rrh->mint);
+ rrh->job = MAC_job_add (ctx,
+ eh,
+ GNUNET_YES,
+ &handle_refresh_reveal_finished,
+ rrh);
+ return rrh;
+}
+
+
+/**
+ * Cancel a refresh reveal request. This function cannot be used
+ * on a request handle if the callback was already invoked.
+ *
+ * @param rrh the refresh reval handle
+ */
+void
+TALER_MINT_refresh_reveal_cancel (struct TALER_MINT_RefreshRevealHandle *rrh)
+{
+ if (NULL != rrh->job)
+ {
+ MAC_job_cancel (rrh->job);
+ rrh->job = NULL;
+ }
+ GNUNET_free_non_null (rrh->db.buf);
+ GNUNET_free (rrh->url);
+ GNUNET_free (rrh->json_enc);
+ GNUNET_free (rrh);
+}
+
+
+/* end of mint_api_refresh.c */