[age restriction] progress 14/n - withdraw and deposit

Age restriction support for
  - withdraw is done and tested
  - deposit is done and tested

TODOs:
  - melt/refresh/reveal
  - link

------

Added functions
 - TALER_age_restriction_commit
 - TALER_age_commitment_derive
 - TALER_age_commitment_hash
 - TALER_age_restriction_commitment_free_inside
 - Hash of age commitment passed around API boundaries

Exchangedb adjustments for denominations
 - all prepared statements re: denominations now handle age_mask
 - signature parameters adjusted

Hash and signature verification of /keys adjusted
 - Hashes of (normal) denominations and age-restricted denominations are
   calculated seperately
 - The hash of the age-restricted ones will then be added to the other
   hash
 - The total hash is signed/verified

Tests for withdraw with age restriction added
 - TALER_EXCHANGE_DenomPublickey now carries age_mask
 - TALER_TESTING_cmd_withdraw_amount* takes age parameter
 - TALER_TESTING_find_pk takes boolean age_restricted
 - WithdrawState carries age_commitment and its hash
 - withdraw_run derives new age commitment, if applicable
 - Added age parameter to testing (13 as example)

Various Fixes and changes
 - Fixes of post handler for /management/extensions
 - Fixes for offline tool extensions signing
 - Slight refactoring of extensions
 - Age restriction extension simplified
   - config is now global to extension
   - added global TEH_age_restriction_enabled and TEH_age_mask in
     taler-exchange-httpd
   - helper functions and macros introduced

1 files changed, 10 insertions, 1 deletions

diff --git a/src/util/test_helper_rsa.c b/src/util/test_helper_rsa.c
index 679f5d7f4..2ead8a6e1 100644
--- a/src/util/test_helper_rsa.c
+++ b/src/util/test_helper_rsa.c
@@ -269,6 +269,7 @@ test_signing (struct TALER_CRYPTO_RsaDenominationHelper *dh)
   bool success = false;
   struct TALER_PlanchetMasterSecretP ps;
   struct TALER_ExchangeWithdrawValues alg_values;
+  struct TALER_AgeCommitmentHash ach;
   struct TALER_CoinPubHash c_hash;
   struct TALER_CoinSpendPrivateKeyP coin_priv;
   union TALER_DenominationBlindingKeyP bks;
@@ -280,6 +281,9 @@ test_signing (struct TALER_CRYPTO_RsaDenominationHelper *dh)
   alg_values.cipher = TALER_DENOMINATION_RSA;
   TALER_planchet_setup_coin_priv (&ps, &alg_values, &coin_priv);
   TALER_planchet_blinding_secret_create (&ps, &alg_values, &bks);
+  GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_WEAK,
+                              &ach,
+                              sizeof(ach));
 
   for (unsigned int i = 0; i<MAX_KEYS; i++)
   {
@@ -296,6 +300,7 @@ test_signing (struct TALER_CRYPTO_RsaDenominationHelper *dh)
                                              &alg_values,
                                              &bks,
                                              &coin_priv,
+                                             &ach,
                                              &c_hash,
                                              &pd));
       GNUNET_log (GNUNET_ERROR_TYPE_INFO,
@@ -440,6 +445,7 @@ perf_signing (struct TALER_CRYPTO_RsaDenominationHelper *dh,
   struct GNUNET_TIME_Relative duration;
   struct TALER_PlanchetMasterSecretP ps;
   struct TALER_CoinSpendPrivateKeyP coin_priv;
+  struct TALER_AgeCommitmentHash ach;
   union TALER_DenominationBlindingKeyP bks;
   struct TALER_ExchangeWithdrawValues alg_values;
 
@@ -447,7 +453,9 @@ perf_signing (struct TALER_CRYPTO_RsaDenominationHelper *dh,
   alg_values.cipher = TALER_DENOMINATION_RSA;
   TALER_planchet_setup_coin_priv (&ps, &alg_values, &coin_priv);
   TALER_planchet_blinding_secret_create (&ps, &alg_values, &bks);
-
+  GNUNET_CRYPTO_random_block (GNUNET_CRYPTO_QUALITY_WEAK,
+                              &ach,
+                              sizeof(ach));
   duration = GNUNET_TIME_UNIT_ZERO;
   TALER_CRYPTO_helper_rsa_poll (dh);
   for (unsigned int j = 0; j<NUM_SIGN_PERFS;)
@@ -477,6 +485,7 @@ perf_signing (struct TALER_CRYPTO_RsaDenominationHelper *dh,
                                                &alg_values,
                                                &bks,
                                                &coin_priv,
+                                               &ach,
                                                &c_hash,
                                                &pd));
         /* use this key as long as it works */