1 files changed, 100 insertions, 0 deletions
diff --git a/common/oid.c b/common/oid.c
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+/*
+ * Copyright (C) 2012 Red Hat Inc.
+ *
+ * Redistribution and use in source and binary forms, with or without
+ * modification, are permitted provided that the following conditions
+ * are met:
+ *
+ *     * Redistributions of source code must retain the above
+ *       copyright notice, this list of conditions and the
+ *       following disclaimer.
+ *     * Redistributions in binary form must reproduce the
+ *       above copyright notice, this list of conditions and
+ *       the following disclaimer in the documentation and/or
+ *       other materials provided with the distribution.
+ *     * The names of contributors to this software may not be
+ *       used to endorse or promote products derived from this
+ *       software without specific prior written permission.
+ *
+ * THIS SOFTWARE IS PROVIDED BY THE COPYRIGHT HOLDERS AND CONTRIBUTORS
+ * "AS IS" AND ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT
+ * LIMITED TO, THE IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS
+ * FOR A PARTICULAR PURPOSE ARE DISCLAIMED. IN NO EVENT SHALL THE
+ * COPYRIGHT OWNER OR CONTRIBUTORS BE LIABLE FOR ANY DIRECT, INDIRECT,
+ * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING,
+ * BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS
+ * OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED
+ * AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY,
+ * OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF
+ * THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH
+ * DAMAGE.
+ *
+ * Author: Stef Walter <stefw@redhat.com>
+ */
+
+#include "config.h"
+
+#include "oid.h"
+
+#include <assert.h>
+#include <stdlib.h>
+#include <string.h>
+
+/*
+ * We deal with OIDs a lot in their DER form. These have the
+ * advantage of having the length encoded in their second byte,
+ * at least for all the OIDs we're interested in.
+ *
+ * The goal here is to avoid carrying around extra length
+ * information about DER encoded OIDs.
+ */
+
+bool
+p11_oid_simple (const unsigned char *oid,
+                int len)
+{
+	return (oid != NULL &&
+	        len > 3 &&                   /* minimum length */
+	        oid[0] == 0x06 &&            /* simple encoding */
+	        (oid[1] & 128) == 0 &&       /* short form length */
+	        (size_t)oid[1] == len - 2);  /* matches length */
+}
+
+unsigned int
+p11_oid_hash (const void *oid)
+{
+	const unsigned char *v = oid;
+	unsigned int hash;
+	int len;
+	int i;
+
+	len = p11_oid_length (v);
+	hash = v[0];
+
+	for (i = 1; i < len; i++)
+		hash = (hash << 5) - hash + v[i];
+
+	return hash;
+}
+
+bool
+p11_oid_equal (const void *oid_one,
+               const void *oid_two)
+{
+	int len_one;
+	int len_two;
+
+	len_one = p11_oid_length (oid_one);
+	len_two = p11_oid_length (oid_two);
+
+	return (len_one == len_two &&
+	        memcmp (oid_one, oid_two, len_one) == 0);
+}
+
+int
+p11_oid_length (const unsigned char *oid)
+{
+	assert (oid[0] == 0x06);
+	assert ((oid[1] & 128) == 0);
+	return (int)oid[1] + 2;
+}