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-rw-r--r--test/monniaux/BearSSL/src/ec/ec_keygen.c86
1 files changed, 86 insertions, 0 deletions
diff --git a/test/monniaux/BearSSL/src/ec/ec_keygen.c b/test/monniaux/BearSSL/src/ec/ec_keygen.c
new file mode 100644
index 00000000..02a30962
--- /dev/null
+++ b/test/monniaux/BearSSL/src/ec/ec_keygen.c
@@ -0,0 +1,86 @@
+/*
+ * Copyright (c) 2018 Thomas Pornin <pornin@bolet.org>
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining
+ * a copy of this software and associated documentation files (the
+ * "Software"), to deal in the Software without restriction, including
+ * without limitation the rights to use, copy, modify, merge, publish,
+ * distribute, sublicense, and/or sell copies of the Software, and to
+ * permit persons to whom the Software is furnished to do so, subject to
+ * the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be
+ * included in all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND,
+ * EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF
+ * MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE AND
+ * NONINFRINGEMENT. IN NO EVENT SHALL THE AUTHORS OR COPYRIGHT HOLDERS
+ * BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER LIABILITY, WHETHER IN AN
+ * ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM, OUT OF OR IN
+ * CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE.
+ */
+
+#include "inner.h"
+
+/* see bearssl_ec.h */
+size_t
+br_ec_keygen(const br_prng_class **rng_ctx,
+ const br_ec_impl *impl, br_ec_private_key *sk,
+ void *kbuf, int curve)
+{
+ const unsigned char *order;
+ unsigned char *buf;
+ size_t len;
+ unsigned mask;
+
+ if (curve < 0 || curve >= 32
+ || ((impl->supported_curves >> curve) & 1) == 0)
+ {
+ return 0;
+ }
+ order = impl->order(curve, &len);
+ while (len > 0 && *order == 0) {
+ order ++;
+ len --;
+ }
+ if (kbuf == NULL || len == 0) {
+ return len;
+ }
+ mask = order[0];
+ mask |= (mask >> 1);
+ mask |= (mask >> 2);
+ mask |= (mask >> 4);
+
+ /*
+ * We generate sequences of random bits of the right size, until
+ * the value is strictly lower than the curve order (we also
+ * check for all-zero values, which are invalid).
+ */
+ buf = kbuf;
+ for (;;) {
+ size_t u;
+ unsigned cc, zz;
+
+ (*rng_ctx)->generate(rng_ctx, buf, len);
+ buf[0] &= mask;
+ cc = 0;
+ u = len;
+ zz = 0;
+ while (u -- > 0) {
+ cc = ((unsigned)(buf[u] - order[u] - cc) >> 8) & 1;
+ zz |= buf[u];
+ }
+ if (cc != 0 && zz != 0) {
+ break;
+ }
+ }
+
+ if (sk != NULL) {
+ sk->curve = curve;
+ sk->x = buf;
+ sk->xlen = len;
+ }
+ return len;
+}