exchange_api_post-purses-PURSE_PUB-merge.c (14751B)
1 /* 2 This file is part of TALER 3 Copyright (C) 2022-2023 Taler Systems SA 4 5 TALER is free software; you can redistribute it and/or modify it under the 6 terms of the GNU General Public License as published by the Free Software 7 Foundation; either version 3, or (at your option) any later version. 8 9 TALER is distributed in the hope that it will be useful, but WITHOUT ANY 10 WARRANTY; without even the implied warranty of MERCHANTABILITY or FITNESS FOR 11 A PARTICULAR PURPOSE. See the GNU General Public License for more details. 12 13 You should have received a copy of the GNU General Public License along with 14 TALER; see the file COPYING. If not, see 15 <http://www.gnu.org/licenses/> 16 */ 17 /** 18 * @file lib/exchange_api_post-purses-PURSE_PUB-merge.c 19 * @brief Implementation of the client to merge a purse 20 * into an account 21 * @author Christian Grothoff 22 */ 23 #include "taler/platform.h" 24 #include <jansson.h> 25 #include <microhttpd.h> /* just for HTTP status codes */ 26 #include <gnunet/gnunet_util_lib.h> 27 #include <gnunet/gnunet_json_lib.h> 28 #include <gnunet/gnunet_curl_lib.h> 29 #include "taler/taler_json_lib.h" 30 #include "taler/taler_exchange_service.h" 31 #include "exchange_api_handle.h" 32 #include "exchange_api_common.h" 33 #include "taler/taler_signatures.h" 34 #include "exchange_api_curl_defaults.h" 35 36 37 /** 38 * @brief A purse merge with deposit handle 39 */ 40 struct TALER_EXCHANGE_PostPursesMergeHandle 41 { 42 43 /** 44 * The curl context for this request. 45 */ 46 struct GNUNET_CURL_Context *ctx; 47 48 /** 49 * The base URL of the exchange. 50 */ 51 char *base_url; 52 53 /** 54 * The keys of the exchange this request handle will use 55 */ 56 struct TALER_EXCHANGE_Keys *keys; 57 58 /** 59 * The url for this request, set during _start. 60 */ 61 char *url; 62 63 /** 64 * Context for #TEH_curl_easy_post(). Keeps the data that must 65 * persist for Curl to make the upload. 66 */ 67 struct TALER_CURL_PostContext post_ctx; 68 69 /** 70 * Handle for the request. 71 */ 72 struct GNUNET_CURL_Job *job; 73 74 /** 75 * Function to call with the result. 76 */ 77 TALER_EXCHANGE_PostPursesMergeCallback cb; 78 79 /** 80 * Closure for @a cb. 81 */ 82 TALER_EXCHANGE_POST_PURSES_MERGE_RESULT_CLOSURE *cb_cls; 83 84 /** 85 * Base URL of the provider hosting the @e reserve_pub. 86 */ 87 char *provider_url; 88 89 /** 90 * Signature for our operation. 91 */ 92 struct TALER_PurseMergeSignatureP merge_sig; 93 94 /** 95 * Expected value in the purse after fees. 96 */ 97 struct TALER_Amount purse_value_after_fees; 98 99 /** 100 * Public key of the reserve public key. 101 */ 102 struct TALER_ReservePublicKeyP reserve_pub; 103 104 /** 105 * Public key of the purse. 106 */ 107 struct TALER_PurseContractPublicKeyP purse_pub; 108 109 /** 110 * Hash over the purse's contract terms. 111 */ 112 struct TALER_PrivateContractHashP h_contract_terms; 113 114 /** 115 * When does the purse expire. 116 */ 117 struct GNUNET_TIME_Timestamp purse_expiration; 118 119 /** 120 * Our merge key. 121 */ 122 struct TALER_PurseMergePrivateKeyP merge_priv; 123 124 /** 125 * Reserve signature affirming the merge. 126 */ 127 struct TALER_ReserveSignatureP reserve_sig; 128 129 /** 130 * The JSON body to post, built during _create and posted during _start. 131 */ 132 json_t *body; 133 134 }; 135 136 137 /** 138 * Function called when we're done processing the 139 * HTTP /purse/$PID/merge request. 140 * 141 * @param cls the `struct TALER_EXCHANGE_PostPursesMergeHandle` 142 * @param response_code HTTP response code, 0 on error 143 * @param response parsed JSON result, NULL on error 144 */ 145 static void 146 handle_purse_merge_finished (void *cls, 147 long response_code, 148 const void *response) 149 { 150 struct TALER_EXCHANGE_PostPursesMergeHandle *pch = cls; 151 const json_t *j = response; 152 struct TALER_EXCHANGE_PostPursesMergeResponse dr = { 153 .hr.reply = j, 154 .hr.http_status = (unsigned int) response_code, 155 .reserve_sig = &pch->reserve_sig 156 }; 157 158 pch->job = NULL; 159 switch (response_code) 160 { 161 case 0: 162 dr.hr.ec = TALER_EC_GENERIC_INVALID_RESPONSE; 163 break; 164 case MHD_HTTP_OK: 165 { 166 struct TALER_Amount total_deposited; 167 struct GNUNET_JSON_Specification spec[] = { 168 GNUNET_JSON_spec_fixed_auto ("exchange_sig", 169 &dr.details.ok.exchange_sig), 170 GNUNET_JSON_spec_fixed_auto ("exchange_pub", 171 &dr.details.ok.exchange_pub), 172 GNUNET_JSON_spec_timestamp ("exchange_timestamp", 173 &dr.details.ok.etime), 174 TALER_JSON_spec_amount ("merge_amount", 175 pch->purse_value_after_fees.currency, 176 &total_deposited), 177 GNUNET_JSON_spec_end () 178 }; 179 180 if (GNUNET_OK != 181 GNUNET_JSON_parse (j, 182 spec, 183 NULL, NULL)) 184 { 185 GNUNET_break_op (0); 186 dr.hr.http_status = 0; 187 dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED; 188 break; 189 } 190 if (GNUNET_OK != 191 TALER_EXCHANGE_test_signing_key (pch->keys, 192 &dr.details.ok.exchange_pub)) 193 { 194 GNUNET_break_op (0); 195 dr.hr.http_status = 0; 196 dr.hr.ec = TALER_EC_EXCHANGE_PURSE_MERGE_EXCHANGE_SIGNATURE_INVALID; 197 break; 198 } 199 if (GNUNET_OK != 200 TALER_exchange_online_purse_merged_verify ( 201 dr.details.ok.etime, 202 pch->purse_expiration, 203 &pch->purse_value_after_fees, 204 &pch->purse_pub, 205 &pch->h_contract_terms, 206 &pch->reserve_pub, 207 pch->provider_url, 208 &dr.details.ok.exchange_pub, 209 &dr.details.ok.exchange_sig)) 210 { 211 GNUNET_break_op (0); 212 dr.hr.http_status = 0; 213 dr.hr.ec = TALER_EC_EXCHANGE_PURSE_MERGE_EXCHANGE_SIGNATURE_INVALID; 214 break; 215 } 216 } 217 break; 218 case MHD_HTTP_BAD_REQUEST: 219 /* This should never happen, either us or the exchange is buggy 220 (or API version conflict); just pass JSON reply to the application */ 221 dr.hr.ec = TALER_JSON_get_error_code (j); 222 dr.hr.hint = TALER_JSON_get_error_hint (j); 223 break; 224 case MHD_HTTP_PAYMENT_REQUIRED: 225 /* purse was not (yet) full */ 226 dr.hr.ec = TALER_JSON_get_error_code (j); 227 dr.hr.hint = TALER_JSON_get_error_hint (j); 228 break; 229 case MHD_HTTP_FORBIDDEN: 230 dr.hr.ec = TALER_JSON_get_error_code (j); 231 dr.hr.hint = TALER_JSON_get_error_hint (j); 232 /* Nothing really to verify, exchange says one of the signatures is 233 invalid; as we checked them, this should never happen, we 234 should pass the JSON reply to the application */ 235 break; 236 case MHD_HTTP_NOT_FOUND: 237 dr.hr.ec = TALER_JSON_get_error_code (j); 238 dr.hr.hint = TALER_JSON_get_error_hint (j); 239 /* Nothing really to verify, this should never 240 happen, we should pass the JSON reply to the application */ 241 break; 242 case MHD_HTTP_CONFLICT: 243 { 244 struct TALER_PurseMergePublicKeyP merge_pub; 245 246 GNUNET_CRYPTO_eddsa_key_get_public (&pch->merge_priv.eddsa_priv, 247 &merge_pub.eddsa_pub); 248 if (GNUNET_OK != 249 TALER_EXCHANGE_check_purse_merge_conflict_ ( 250 &pch->merge_sig, 251 &merge_pub, 252 &pch->purse_pub, 253 pch->provider_url, 254 j)) 255 { 256 GNUNET_break_op (0); 257 dr.hr.http_status = 0; 258 dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED; 259 break; 260 } 261 break; 262 } 263 break; 264 case MHD_HTTP_GONE: 265 /* could happen if denomination was revoked */ 266 /* Note: one might want to check /keys for revocation 267 signature here, alas tricky in case our /keys 268 is outdated => left to clients */ 269 dr.hr.ec = TALER_JSON_get_error_code (j); 270 dr.hr.hint = TALER_JSON_get_error_hint (j); 271 break; 272 case MHD_HTTP_UNAVAILABLE_FOR_LEGAL_REASONS: 273 { 274 struct GNUNET_JSON_Specification spec[] = { 275 GNUNET_JSON_spec_uint64 ( 276 "requirement_row", 277 &dr.details.unavailable_for_legal_reasons.requirement_row), 278 GNUNET_JSON_spec_end () 279 }; 280 281 if (GNUNET_OK != 282 GNUNET_JSON_parse (j, 283 spec, 284 NULL, NULL)) 285 { 286 GNUNET_break_op (0); 287 dr.hr.http_status = 0; 288 dr.hr.ec = TALER_EC_GENERIC_REPLY_MALFORMED; 289 break; 290 } 291 } 292 break; 293 case MHD_HTTP_INTERNAL_SERVER_ERROR: 294 dr.hr.ec = TALER_JSON_get_error_code (j); 295 dr.hr.hint = TALER_JSON_get_error_hint (j); 296 /* Server had an internal issue; we should retry, but this API 297 leaves this to the application */ 298 break; 299 default: 300 /* unexpected response code */ 301 dr.hr.ec = TALER_JSON_get_error_code (j); 302 dr.hr.hint = TALER_JSON_get_error_hint (j); 303 GNUNET_log (GNUNET_ERROR_TYPE_ERROR, 304 "Unexpected response code %u/%d for exchange deposit\n", 305 (unsigned int) response_code, 306 dr.hr.ec); 307 GNUNET_break_op (0); 308 break; 309 } 310 if (NULL != pch->cb) 311 { 312 pch->cb (pch->cb_cls, 313 &dr); 314 pch->cb = NULL; 315 } 316 TALER_EXCHANGE_post_purses_merge_cancel (pch); 317 } 318 319 320 struct TALER_EXCHANGE_PostPursesMergeHandle * 321 TALER_EXCHANGE_post_purses_merge_create ( 322 struct GNUNET_CURL_Context *ctx, 323 const char *url, 324 struct TALER_EXCHANGE_Keys *keys, 325 const char *reserve_exchange_url, 326 const struct TALER_ReservePrivateKeyP *reserve_priv, 327 const struct TALER_PurseContractPublicKeyP *purse_pub, 328 const struct TALER_PurseMergePrivateKeyP *merge_priv, 329 const struct TALER_PrivateContractHashP *h_contract_terms, 330 uint8_t min_age, 331 const struct TALER_Amount *purse_value_after_fees, 332 struct GNUNET_TIME_Timestamp purse_expiration, 333 struct GNUNET_TIME_Timestamp merge_timestamp) 334 { 335 struct TALER_EXCHANGE_PostPursesMergeHandle *pch; 336 struct TALER_NormalizedPayto reserve_url; 337 338 pch = GNUNET_new (struct TALER_EXCHANGE_PostPursesMergeHandle); 339 pch->ctx = ctx; 340 pch->base_url = GNUNET_strdup (url); 341 pch->merge_priv = *merge_priv; 342 pch->purse_pub = *purse_pub; 343 pch->h_contract_terms = *h_contract_terms; 344 pch->purse_expiration = purse_expiration; 345 pch->purse_value_after_fees = *purse_value_after_fees; 346 if (NULL == reserve_exchange_url) 347 pch->provider_url = GNUNET_strdup (url); 348 else 349 pch->provider_url = GNUNET_strdup (reserve_exchange_url); 350 GNUNET_CRYPTO_eddsa_key_get_public (&reserve_priv->eddsa_priv, 351 &pch->reserve_pub.eddsa_pub); 352 353 reserve_url = TALER_reserve_make_payto (pch->provider_url, 354 &pch->reserve_pub); 355 if (NULL == reserve_url.normalized_payto) 356 { 357 GNUNET_break (0); 358 GNUNET_free (pch->provider_url); 359 GNUNET_free (pch->base_url); 360 GNUNET_free (pch); 361 return NULL; 362 } 363 TALER_wallet_purse_merge_sign (reserve_url, 364 merge_timestamp, 365 purse_pub, 366 merge_priv, 367 &pch->merge_sig); 368 { 369 struct TALER_Amount zero_purse_fee; 370 371 GNUNET_assert (GNUNET_OK == 372 TALER_amount_set_zero (purse_value_after_fees->currency, 373 &zero_purse_fee)); 374 TALER_wallet_account_merge_sign (merge_timestamp, 375 purse_pub, 376 purse_expiration, 377 h_contract_terms, 378 purse_value_after_fees, 379 &zero_purse_fee, 380 min_age, 381 TALER_WAMF_MODE_MERGE_FULLY_PAID_PURSE, 382 reserve_priv, 383 &pch->reserve_sig); 384 } 385 // FIXME: move JSON construction into _start() function 386 pch->body = GNUNET_JSON_PACK ( 387 TALER_JSON_pack_normalized_payto ("payto_uri", 388 reserve_url), 389 GNUNET_JSON_pack_data_auto ("merge_sig", 390 &pch->merge_sig), 391 GNUNET_JSON_pack_data_auto ("reserve_sig", 392 &pch->reserve_sig), 393 GNUNET_JSON_pack_timestamp ("merge_timestamp", 394 merge_timestamp)); 395 GNUNET_free (reserve_url.normalized_payto); 396 if (NULL == pch->body) 397 { 398 GNUNET_break (0); 399 GNUNET_free (pch->provider_url); 400 GNUNET_free (pch->base_url); 401 GNUNET_free (pch); 402 return NULL; 403 } 404 pch->keys = TALER_EXCHANGE_keys_incref (keys); 405 return pch; 406 } 407 408 409 enum TALER_ErrorCode 410 TALER_EXCHANGE_post_purses_merge_start ( 411 struct TALER_EXCHANGE_PostPursesMergeHandle *pch, 412 TALER_EXCHANGE_PostPursesMergeCallback cb, 413 TALER_EXCHANGE_POST_PURSES_MERGE_RESULT_CLOSURE *cb_cls) 414 { 415 char arg_str[sizeof (pch->purse_pub) * 2 + 32]; 416 CURL *eh; 417 418 pch->cb = cb; 419 pch->cb_cls = cb_cls; 420 421 { 422 char pub_str[sizeof (pch->purse_pub) * 2]; 423 char *end; 424 425 end = GNUNET_STRINGS_data_to_string ( 426 &pch->purse_pub, 427 sizeof (pch->purse_pub), 428 pub_str, 429 sizeof (pub_str)); 430 *end = '\0'; 431 GNUNET_snprintf (arg_str, 432 sizeof (arg_str), 433 "purses/%s/merge", 434 pub_str); 435 } 436 pch->url = TALER_url_join (pch->base_url, 437 arg_str, 438 NULL); 439 if (NULL == pch->url) 440 { 441 GNUNET_break (0); 442 return TALER_EC_GENERIC_CONFIGURATION_INVALID; 443 } 444 GNUNET_log (GNUNET_ERROR_TYPE_DEBUG, 445 "URL for purse merge: `%s'\n", 446 pch->url); 447 eh = TALER_EXCHANGE_curl_easy_get_ (pch->url); 448 if ( (NULL == eh) || 449 (GNUNET_OK != 450 TALER_curl_easy_post (&pch->post_ctx, 451 eh, 452 pch->body)) ) 453 { 454 GNUNET_break (0); 455 if (NULL != eh) 456 curl_easy_cleanup (eh); 457 return TALER_EC_GENERIC_CURL_ALLOCATION_FAILURE; 458 } 459 pch->job = GNUNET_CURL_job_add2 (pch->ctx, 460 eh, 461 pch->post_ctx.headers, 462 &handle_purse_merge_finished, 463 pch); 464 if (NULL == pch->job) 465 return TALER_EC_GENERIC_INTERNAL_INVARIANT_FAILURE; 466 return TALER_EC_NONE; 467 } 468 469 470 void 471 TALER_EXCHANGE_post_purses_merge_cancel ( 472 struct TALER_EXCHANGE_PostPursesMergeHandle *pch) 473 { 474 if (NULL != pch->job) 475 { 476 GNUNET_CURL_job_cancel (pch->job); 477 pch->job = NULL; 478 } 479 GNUNET_free (pch->url); 480 GNUNET_free (pch->base_url); 481 GNUNET_free (pch->provider_url); 482 TALER_curl_easy_post_finished (&pch->post_ctx); 483 TALER_EXCHANGE_keys_decref (pch->keys); 484 json_decref (pch->body); 485 GNUNET_free (pch); 486 } 487 488 489 /* end of exchange_api_post-purses-PURSE_PUB-merge.c */