Second night's commit.

We're a bit closer to something sane, now. We can wrap, but not unwrap,
packets.

Asymmetric encryption is *big*. encrypted text with a 4096-bit RSA
public key is 512 bytes. We can't fragment yet. Fortunately, this
isn't an infinite regress once we *can* fragment.

Performance is still a big question mark, of course.

There may still be endianness issues hanging around.

The eid<->rloc map is almost certainly far, far too slow to be of
any use in the real world.

pass-1/rlocs.h

@@ -0,0 +1,65 @@
+#ifndef _RLOCS_H_
+#define _RLOCS_H_
+
+#include <json/json_object.h>
+#include <netinet/in.h>
+
+#include <openssl/rsa.h>
+
+// For now. We can dynamically allocate later.
+#define MAX_RLOCS 64
+#define MAX_EID_MAPPINGS 256
+
+struct rloc {
+    short family;
+    union {
+        struct in_addr  ip4;
+        struct in6_addr ip6;
+    } addr;
+    
+    RSA* key;
+};
+
+
+struct ip4_eid_map_entry {
+    struct in_addr network;
+    struct in_addr broadcast;
+    unsigned int mask;
+    struct rloc *rloc;
+};
+
+struct ip6_eid_map_entry {
+    struct in6_addr network;
+    struct in6_addr broadcast;
+    unsigned int mask;
+    struct rloc *rloc;    
+};
+
+struct rlocs {
+    json_object* config;
+    
+    size_t num_entries;
+    struct rloc entries[MAX_RLOCS];
+    
+    size_t num_ip4_map_entries;
+    struct ip4_eid_map_entry ip4_mappings[MAX_EID_MAPPINGS];
+    
+    size_t num_ip6_map_entries;
+    struct ip6_eid_map_entry ip6_mappings[MAX_EID_MAPPINGS];
+};
+
+
+void rlocs_init(void);
+
+struct rlocs *rlocs_new( char *filename );
+
+struct rloc *rloc_find_for_ipv4( struct rlocs *reg, struct in_addr *eid );
+struct rloc *rloc_find_for_ipv6( struct rlocs *reg, struct in6_addr *eid );
+struct rloc *rloc_find_by_address( struct rlocs *reg, struct in_addr *ipv4, struct in6_addr *ipv6 );
+
+/* Returns -1 on error, or number of bytes written */
+ssize_t rloc_encrypt( struct rloc *rloc, unsigned char *data, size_t data_len, unsigned char *dest, size_t dest_len );
+
+void rlocs_free( struct rlocs *registry );
+
+#endif