Replaced system SQLite with SQLCipher to support encrypted database

Sources/DataLiteC/libtomcrypt/pk/rsa/rsa_key.c

@@ -0,0 +1,101 @@
+/* LibTomCrypt, modular cryptographic library -- Tom St Denis */
+/* SPDX-License-Identifier: Unlicense */
+#include "tomcrypt_private.h"
+
+/**
+  @file rsa_key.c
+  Free an RSA key, Tom St Denis
+  Basic operations on an RSA key, Steffen Jaeckel
+*/
+
+#ifdef LTC_MRSA
+static void s_mpi_shrink_multi(void **a, ...)
+{
+   void **cur;
+   unsigned n;
+   int err;
+   va_list args;
+   void *tmp[10] = { 0 };
+   void **arg[10] = { 0 };
+
+   /* We re-allocate in the order that we received the varargs */
+   n = 0;
+   err = CRYPT_ERROR;
+   cur = a;
+   va_start(args, a);
+   while (cur != NULL) {
+      if (n >= sizeof(tmp)/sizeof(tmp[0])) {
+         goto out;
+      }
+      if (*cur != NULL) {
+         arg[n] = cur;
+         if ((err = ltc_mp_init_copy(&tmp[n], *arg[n])) != CRYPT_OK) {
+            goto out;
+         }
+         n++;
+      }
+      cur = va_arg(args, void**);
+   }
+   va_end(args);
+
+   /* but we clear the old values in the reverse order */
+   while (n != 0 && arg[--n] != NULL) {
+      ltc_mp_clear(*arg[n]);
+      *arg[n] = tmp[n];
+   }
+out:
+   va_end(args);
+   /* clean-up after an error
+    * or after this was called with too many args
+    */
+   if ((err != CRYPT_OK) ||
+         (n >= sizeof(tmp)/sizeof(tmp[0]))) {
+      for (n = 0; n < sizeof(tmp)/sizeof(tmp[0]); ++n) {
+         if (tmp[n] != NULL) {
+            ltc_mp_clear(tmp[n]);
+         }
+      }
+   }
+}
+
+/**
+  This shrinks the allocated memory of a RSA key
+
+     It will use up some more memory temporarily,
+     but then it will free-up the entire sequence that
+     was once allocated when the key was created/populated.
+
+     This only works with libtommath >= 1.2.0 in earlier versions
+     it has the inverse effect due to the way it worked internally.
+     Also works for GNU MP, tomsfastmath naturally shows no effect.
+
+  @param key   The RSA key to shrink
+*/
+void rsa_shrink_key(rsa_key *key)
+{
+   LTC_ARGCHKVD(key != NULL);
+   s_mpi_shrink_multi(&key->e, &key->d, &key->N, &key->dQ, &key->dP, &key->qP, &key->p, &key->q, NULL);
+}
+
+/**
+  Init an RSA key
+  @param key   The RSA key to initialize
+  @return CRYPT_OK if successful
+*/
+int rsa_init(rsa_key *key)
+{
+   LTC_ARGCHK(key != NULL);
+   return ltc_mp_init_multi(&key->e, &key->d, &key->N, &key->dQ, &key->dP, &key->qP, &key->p, &key->q, LTC_NULL);
+}
+
+/**
+  Free an RSA key from memory
+  @param key   The RSA key to free
+*/
+void rsa_free(rsa_key *key)
+{
+   LTC_ARGCHKVD(key != NULL);
+   ltc_mp_cleanup_multi(&key->q, &key->p, &key->qP, &key->dP, &key->dQ, &key->N, &key->d, &key->e, LTC_NULL);
+}
+
+#endif