/* -*-c-*-
*
- * $Id: buf.c,v 1.2 2003/11/10 22:18:30 mdw Exp $
+ * $Id$
*
* Buffer handling
*
* MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: buf.c,v $
- * Revision 1.2 2003/11/10 22:18:30 mdw
- * Build fixes.
- *
- * Revision 1.1 2003/10/11 21:02:33 mdw
- * Import buf stuff from tripe.
- *
- * Revision 1.4 2001/06/19 22:09:54 mdw
- * Expose interface, for use in the proxy.
- *
- * Revision 1.3 2001/03/03 12:06:48 mdw
- * Use 16-bit lengths on MPs, since there's a packet limit of 64K anyway.
- *
- * Revision 1.2 2001/02/16 21:23:20 mdw
- * Various minor changes. Check that MPs are in canonical form when
- * loading.
- *
- * Revision 1.1 2001/02/03 20:26:37 mdw
- * Initial checkin.
- *
- */
-
/*----- Header files ------------------------------------------------------*/
#include <string.h>
#include "mp.h"
+#include "ec.h"
#include "buf.h"
/*----- Main code ---------------------------------------------------------*/
return (0);
}
+/* --- @findz@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @size_t *nn@ = where to put the length
+ *
+ * Returns: Zero if OK, nonzero if there wasn't a null byte to be found.
+ *
+ * Use: Finds a terminating null byte.
+ */
+
+static int findz(buf *b, size_t *nn)
+{
+ octet *p;
+
+ if ((p = memchr(BCUR(b), 0, BLEN(b))) == 0) {
+ buf_break(b);
+ return (-1);
+ }
+ *nn = p - BCUR(b);
+ return (0);
+}
+
+#define DOSUFFIXES(DO) DO(8) DO(16) DO(32) DO(z)
+
+/* --- @buf_getmem{8,16,32,z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @size_t *nn@ = where to put the length
+ *
+ * Returns: Pointer to the buffer data, or null.
+ *
+ * Use: Gets a chunk of memory from a buffer. The number, @16@ or
+ * @32@, is the width of the length; @z@ means null-terminated.
+ */
+
+void *buf_getmem8(buf *b, size_t *nn)
+{
+ int n;
+
+ if ((n = buf_getbyte(b)) < 0) return (0);
+ *nn = n;
+ return (buf_get(b, n));
+}
+
+void *buf_getmem16(buf *b, size_t *nn)
+{
+ uint16 n;
+
+ if (buf_getu16(b, &n)) return (0);
+ *nn = n;
+ return (buf_get(b, n));
+}
+
+void *buf_getmem32(buf *b, size_t *nn)
+{
+ uint32 n;
+
+ if (buf_getu32(b, &n)) return (0);
+ *nn = n;
+ return (buf_get(b, n));
+}
+
+void *buf_getmemz(buf *b, size_t *nn)
+{
+ if (findz(b, nn)) return (0);
+ return (buf_get(b, *nn));
+}
+
+/* --- @buf_putmem{8,16,32,z} --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @const void *p@ = pointer to data to write
+ * @size_t n@ = length to write
+ *
+ * Returns: Zero if OK, nonzero if there wasn't enough space.
+ *
+ * Use: Writes a chunk of data to a buffer. The number, @16@ or
+ * @32@, is the width of the length; @z@ means null-terminated.
+ */
+
+int buf_putmem8(buf *b, const void *p, size_t n)
+{
+ assert(n <= 0xfful);
+ if (buf_putbyte(b, n) || buf_put(b, p, n))
+ return (-1);
+ return (0);
+}
+
+int buf_putmem16(buf *b, const void *p, size_t n)
+{
+ assert(n <= 0xfffful);
+ if (buf_putu16(b, n) || buf_put(b, p, n))
+ return (-1);
+ return (0);
+}
+
+int buf_putmem32(buf *b, const void *p, size_t n)
+{
+ assert(n <= 0xfffffffful);
+ if (buf_putu32(b, n) || buf_put(b, p, n))
+ return (-1);
+ return (0);
+}
+
+int buf_putmemz(buf *b, const void *p, size_t n)
+{
+ octet *q;
+
+ assert(!memchr(p, 0, n));
+ if ((q = buf_get(b, n + 1)) == 0)
+ return (-1);
+ memcpy(q, p, n);
+ q[n] = 0;
+ return (0);
+}
+
+/* --- @buf_getbuf{8,16,32,z}@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @buf *bb@ = where to put the result
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Gets a block of data from a buffer, and writes its bounds to
+ * another buffer. The number, @16@ or @32@, is the width of
+ * the length; @z@ means null-terminated.
+ */
+
+#define GETBUF(suff) int buf_getbuf##suff(buf *b, buf *bb) \
+{ \
+ void *p; \
+ size_t n; \
+ \
+ if ((p = buf_getmem##suff(b, &n)) == 0) \
+ return (-1); \
+ buf_init(bb, p, n); \
+ return (0); \
+}
+DOSUFFIXES(GETBUF)
+
+/* --- @buf_putbuf{8,16,32,z}@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @buf *bb@ = buffer to write
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts the contents of a buffer to a buffer. The number, @16@
+ * or @32@, is the width of the length; @z@ means null-
+ * terminated.
+ */
+
+#define PUTBUF(suff) int buf_putbuf##suff(buf *b, buf *bb) \
+ { return (buf_putmem##suff(b, BBASE(bb), BLEN(bb))); }
+DOSUFFIXES(PUTBUF)
+
+/* --- @buf_getstr{8,16,32,z}@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @dstr *d@ = where to put the result
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Gets a block of data from a buffer, and writes its contents
+ * to a string. The number, @16@ or @32@, is the width of the
+ * length; @z@ means null-terminated.
+ */
+
+#define GETSTR(suff) int buf_getstr##suff(buf *b, dstr *d) \
+{ \
+ void *p; \
+ size_t n; \
+ \
+ if ((p = buf_getmem##suff(b, &n)) == 0) \
+ return (-1); \
+ DPUTM(d, p, n); \
+ return (0); \
+}
+DOSUFFIXES(GETSTR)
+
+/* --- @buf_putstr{8,16,32,z}@ --- *
+ *
+ * Arguments: @buf *b@ = pointer to a buffer block
+ * @dstr *d@ = string to write
+ *
+ * Returns: Zero if it worked, nonzero if there wasn't enough space.
+ *
+ * Use: Puts a string to a buffer, and writes its bounds to
+ * another buffer. The number, @16@ or @32@, is the width of
+ * the length; @z@ means null-terminated.
+ */
+
+#define PUTSTR(suff) int buf_putstr##suff(buf *b, dstr *d) \
+ { return (buf_putmem##suff(b, d->buf, d->len)); }
+DOSUFFIXES(PUTSTR)
+
/* --- @buf_getmp@ --- *
*
* Arguments: @buf *b@ = pointer to a buffer block
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);
- if (mp_octets(m) != sz) {
+ n = mp_octets(m);
+ if (n != sz && n != 0 && sz != 1) {
mp_drop(m);
return (0);
}
{
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);
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 -------------------------------------------------*/
projects / u / mdw / catacomb / blobdiff