--- /dev/null
+/* -*-c-*-
+ *
+ * Buffer handling
+ *
+ * (c) 2001 Straylight/Edgeware
+ */
+
+/*----- Licensing notice --------------------------------------------------*
+ *
+ * This file is part of Catacomb.
+ *
+ * Catacomb is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU Library General Public License as
+ * published by the Free Software Foundation; either version 2 of the
+ * License, or (at your option) any later version.
+ *
+ * Catacomb 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 Library General Public License for more details.
+ *
+ * You should have received a copy of the GNU Library General Public
+ * License along with Catacomb; if not, write to the Free
+ * Software Foundation, Inc., 59 Temple Place - Suite 330, Boston,
+ * MA 02111-1307, USA.
+ */
+
+/*----- Header files ------------------------------------------------------*/
+
+#include <string.h>
+
+#include "mp.h"
+#include "ec.h"
+#include "buf.h"
+
+/*----- Main code ---------------------------------------------------------*/
+
+/* --- @buf_getmp@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ *
+ * Returns: A multiprecision integer, or null if there wasn't one there.
+ *
+ * Use: Gets a multiprecision integer from a buffer.
+ */
+
+mp *buf_getmp(buf *b)
+{
+ uint16 sz;
+ size_t n;
+ mp *m;
+ if (buf_getu16(b, &sz) || buf_ensure(b, sz))
+ return (0);
+ m = mp_loadb(MP_NEW, BCUR(b), sz);
+ n = mp_octets(m);
+ if (n != sz && n != 0 && sz != 1) {
+ mp_drop(m);
+ return (0);
+ }
+ BSTEP(b, sz);
+ return (m);
+}
+
+/* --- @buf_putmp@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @mp *m@ = a multiprecision integer
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a multiprecision integer to a buffer.
+ */
+
+int buf_putmp(buf *b, mp *m)
+{
+ size_t sz = mp_octets(m);
+ assert(sz < MASK16);
+ if (!sz) sz = 1;
+ if (buf_putu16(b, sz) || buf_ensure(b, sz))
+ return (-1);
+ mp_storeb(m, BCUR(b), sz);
+ BSTEP(b, sz);
+ return (0);
+}
+
+/* --- @buf_getec@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @ec *p@ = where to put the point
+ *
+ * Returns: Zero if it worked, nonzero if it failed.
+ *
+ * Use: Gets a multiprecision integer from a buffer. The point must
+ * be initialized.
+ */
+
+int buf_getec(buf *b, ec *p)
+{
+ mp *x = 0, *y = 0;
+ uint16 n;
+ if (buf_ensure(b, 2)) return (-1);
+ n = LOAD16(BCUR(b)); if (!n) { BSTEP(b, 2); EC_SETINF(p); return (0); }
+ if ((x = buf_getmp(b)) == 0 || (y = buf_getmp(b)) == 0) {
+ mp_drop(x); mp_drop(y); return (-1);
+ }
+ EC_DESTROY(p); p->x = x; p->y = y; p->z = 0;
+ return (0);
+}
+
+/* --- @buf_putec@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @ec *p@ = an elliptic curve point
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts an elliptic curve point to a buffer.
+ */
+
+int buf_putec(buf *b, ec *p)
+{
+ if (EC_ATINF(p)) return (buf_putu16(b, 0));
+ if (buf_putmp(b, p->x) || buf_putmp(b, p->y)) return (-1);
+ return (0);
+}
+
+/*----- That's all, folks -------------------------------------------------*/