Move lib into src

1 files changed, 69 insertions, 0 deletions

diff --git a/src/lib/cert/x509/key_constraint.cpp b/src/lib/cert/x509/key_constraint.cpp
new file mode 100644
index 000000000..8a4b3deb3
--- /dev/null
+++ b/src/lib/cert/x509/key_constraint.cpp
@@ -0,0 +1,69 @@
+/*
+* KeyUsage
+* (C) 1999-2007 Jack Lloyd
+*
+* Distributed under the terms of the Botan license
+*/
+
+#include <botan/key_constraint.h>
+#include <botan/x509_key.h>
+#include <botan/ber_dec.h>
+
+namespace Botan {
+
+namespace BER {
+
+/*
+* Decode a BER encoded KeyUsage
+*/
+void decode(BER_Decoder& source, Key_Constraints& key_usage)
+   {
+   BER_Object obj = source.get_next_object();
+
+   if(obj.type_tag != BIT_STRING || obj.class_tag != UNIVERSAL)
+      throw BER_Bad_Tag("Bad tag for usage constraint",
+                        obj.type_tag, obj.class_tag);
+   if(obj.value.size() != 2 && obj.value.size() != 3)
+      throw BER_Decoding_Error("Bad size for BITSTRING in usage constraint");
+   if(obj.value[0] >= 8)
+      throw BER_Decoding_Error("Invalid unused bits in usage constraint");
+
+   const byte mask = (0xFF << obj.value[0]);
+   obj.value[obj.value.size()-1] &= mask;
+
+   u16bit usage = 0;
+   for(size_t j = 1; j != obj.value.size(); ++j)
+      usage = (obj.value[j] << 8) | usage;
+
+   key_usage = Key_Constraints(usage);
+   }
+
+}
+
+/*
+* Find the allowable key constraints
+*/
+Key_Constraints find_constraints(const Public_Key& pub_key,
+                                 Key_Constraints limits)
+   {
+   const std::string name = pub_key.algo_name();
+
+   size_t constraints = 0;
+
+   if(name == "DH" || name == "ECDH")
+      constraints |= KEY_AGREEMENT;
+
+   if(name == "RSA" || name == "ElGamal")
+      constraints |= KEY_ENCIPHERMENT | DATA_ENCIPHERMENT;
+
+   if(name == "RSA" || name == "RW" || name == "NR" ||
+      name == "DSA" || name == "ECDSA")
+      constraints |= DIGITAL_SIGNATURE | NON_REPUDIATION;
+
+   if(limits)
+      constraints &= limits;
+
+   return Key_Constraints(constraints);
+   }
+
+}