/* -*-c-*-
*
- * $Id: tripe.h,v 1.12 2003/04/06 10:25:17 mdw Exp $
+ * $Id$
*
* Main header file for TrIPE
*
* Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
*/
-/*----- Revision history --------------------------------------------------*
- *
- * $Log: tripe.h,v $
- * Revision 1.12 2003/04/06 10:25:17 mdw
- * Support Linux TUN/TAP device. Fix some bugs.
- *
- * Revision 1.11 2002/01/13 14:57:42 mdw
- * Fix crap typo.
- *
- * Revision 1.10 2002/01/13 14:54:58 mdw
- * Provide MGF macros.
- *
- * Revision 1.9 2001/06/22 19:40:36 mdw
- * Support expiry of other peers' public keys.
- *
- * Revision 1.8 2001/06/19 22:10:57 mdw
- * Some more constants for the algorithms. Document the packet format
- * change for non-malleability. Moved @buf@ definitions to separate header
- * file.
- *
- * Revision 1.7 2001/03/03 12:07:08 mdw
- * Rename word get and put functions now that there's 16-bit support.
- *
- * Revision 1.6 2001/02/19 19:11:09 mdw
- * Output buffering on admin connections.
- *
- * Revision 1.5 2001/02/16 21:41:43 mdw
- * Major changes. See source files for details.
- *
- * Revision 1.4 2001/02/05 19:56:37 mdw
- * Sequence number protection, and BSD tunnels.
- *
- * Revision 1.3 2001/02/04 01:17:55 mdw
- * Create a configuration header file to tidy up command lines.
- *
- * Revision 1.2 2001/02/03 22:40:29 mdw
- * Put timer information into the entropy pool when packets are received
- * and on similar events. Reseed the generator on the interval timer.
- *
- * Revision 1.1 2001/02/03 20:26:37 mdw
- * Initial checkin.
- *
- */
-
#ifndef TRIPE_H
#define TRIPE_H
#include <assert.h>
#include <ctype.h>
#include <errno.h>
+#include <limits.h>
#include <signal.h>
#include <stdarg.h>
#include <stddef.h>
#include <arpa/inet.h>
#include <netdb.h>
-#if TUN_TYPE == TUN_LINUX
-# include <linux/if.h>
-# include <linux/if_tun.h>
-#endif
-
#include <pwd.h>
#include <grp.h>
#include <mLib/sub.h>
#include <mLib/trace.h>
+#include <catacomb/buf.h>
+
#include <catacomb/gcipher.h>
#include <catacomb/gmac.h>
#include <catacomb/grand.h>
#include <catacomb/rand.h>
#include <catacomb/mp.h>
-#include <catacomb/mpmont.h>
#include <catacomb/mprand.h>
#include <catacomb/dh.h>
+#include <catacomb/ec.h>
+#include <catacomb/ec-keys.h>
+#include <catacomb/group.h>
-#include "buf.h"
+#include "tripe-protocol.h"
#include "util.h"
#undef sun
/*----- Magic numbers -----------------------------------------------------*/
-/* --- Tunnel types --- */
-
-#define TUN_NOTDEF 0
-#define TUN_UNET 1
-#define TUN_BSD 2
-#define TUN_LINUX 3
-
/* --- Trace flags --- */
#define T_TUNNEL 1u
#define PKBUFSZ 65536
-/*----- TrIPE protocol ----------------------------------------------------*/
-
-/* --- TrIPE message format --- *
- *
- * A packet begins with a single-byte message type. The top four bits are a
- * category code used to send the message to the right general place in the
- * code; the bottom bits identify the actual message type.
- */
-
-#define MSG_CATMASK 0xf0
-#define MSG_TYPEMASK 0x0f
-
-/* --- Encrypted message packets --- *
- *
- * Messages of category @MSG_PACKET@ contain encrypted network packets. The
- * message content is a symmetric-encrypted block (see below). Reception of
- * a packet encrypted under a new key implicitly permits that key to be used
- * to send further packets.
- *
- * The only packet type accepted is zero.
- *
- * Packets may be encrypted under any live keyset, but should use the most
- * recent one.
- */
-
-#define MSG_PACKET 0x00
-
-/* --- Key exchange packets --- */
-
-#define MSG_KEYEXCH 0x10
-
-#define KX_PRECHAL 0u
-#define KX_COOKIE 1u
-#define KX_CHAL 2u
-#define KX_REPLY 3u
-#define KX_SWITCH 4u
-#define KX_SWITCHOK 5u
-#define KX_NMSG 6u
-
-/* --- Symmetric encryption and keysets --- *
- *
- * Packets consist of an 80-bit MAC, a 32-bit sequence number, and the
- * encrypted payload.
- *
- * The plaintext is encrypted using Blowfish in CBC mode with ciphertext
- * stealing (as described in [Schneier]. The initialization vector is
- * selected randomly, and prepended to the actual ciphertext.
- *
- * The MAC is computed using the HMAC construction with RIPEMD160 over the
- * sequence number and the ciphertext (with IV); the first 80 bits of the
- * output are used. (This is the minimum allowed by the draft FIPS for HMAC,
- * and the recommended truncation.)
- *
- * A keyset consists of
- *
- * * an integrity (MAC) key;
- * * a confidentiality (encryption) key; and
- * * a sequence numbering space
- *
- * in each direction. The packets sent by a host encrypted under a
- * particular keyset are assigned consecutive sequence numbers starting from
- * zero. The receiving host must ensure that it only accepts each packet at
- * most once. It should maintain a window of sequence numbers: packets with
- * numbers beyond the end of the window are accepted and cause the window to
- * be advanced; packets with numbers before the start of the window are
- * rejected; packets with numbers which appear within the window are accepted
- * only if the number has not been seen before.
- *
- * When a host sends a @KX_SWITCH@ or @KX_SWITCHOK@ message, it installs the
- * newly-negotiated keyset in a `listen-only' state: it may not send a packet
- * encrypted under the keyset until either it has received a @KX_SWITCH@ or
- * @KX_SWITCHOK@ message, or a @MSG_PACKET@ encrypted under the keyset, from
- * its peer.
- */
-
/*----- Cipher selections -------------------------------------------------*/
-#include <catacomb/blowfish.h>
-#include <catacomb/blowfish-cbc.h>
-#include <catacomb/blowfish-counter.h>
-#include <catacomb/rmd160.h>
-#include <catacomb/rmd160-hmac.h>
-
-#define CIPHER (&blowfish_cbc)
-#define MAC (&rmd160_hmac)
+typedef struct algswitch {
+ const gccipher *c; /* Symmetric encryption scheme */
+ const gccipher *mgf; /* Mask-generation function */
+ const gchash *h; /* Hash function */
+ const gcmac *m; /* Message authentication code */
+ size_t hashsz; /* Hash output size */
+ size_t tagsz; /* Length to truncate MAC tags */
+ size_t cksz, mksz; /* Key lengths for @c@ and @m@ */
+} algswitch;
-#define HASH_CTX rmd160_ctx
-#define HASH_INIT rmd160_init
-#define HASH rmd160_hash
-#define HASH_STRING(c, s) HASH((c), s, sizeof(s))
-#define HASH_DONE rmd160_done
-#define HASHSZ RMD160_HASHSZ
+extern algswitch algs;
-#define MGF_CTX blowfish_counterctx
-#define MGF_INIT blowfish_counterinit
-#define MGF_CRYPT blowfish_counterencrypt
+#define MAXHASHSZ 64 /* Largest possible hash size */
-#define SEQSZ 4
-#define IVSZ BLOWFISH_BLKSZ
-#define MACSZ 10
+#define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
/*----- Data structures ---------------------------------------------------*/
typedef struct keyset {
struct keyset *next; /* Next active keyset in the list */
unsigned ref; /* Reference count for keyset */
+ struct peer *p; /* Pointer to peer structure */
time_t t_exp; /* Expiry time for this keyset */
unsigned long sz_exp; /* Data limit for the keyset */
T( unsigned seq; ) /* Sequence number for tracing */
unsigned f; /* Various useful flags */
gcipher *cin, *cout; /* Keyset ciphers for encryption */
+ size_t tagsz; /* Length to truncate MAC tags */
gmac *min, *mout; /* Keyset MACs for integrity */
uint32 oseq; /* Outbound sequence number */
uint32 iseq, iwin; /* Inbound sequence number */
typedef struct kxchal {
struct keyexch *kx; /* Pointer back to key exchange */
- mp *c; /* Responder's challenge */
- mp *r; /* My reply to the challenge */
+ ge *c; /* Responder's challenge */
+ ge *r; /* My reply to the challenge */
keyset *ks; /* Pointer to temporary keyset */
unsigned f; /* Various useful flags */
sel_timer t; /* Response timer for challenge */
- octet hc[HASHSZ]; /* Hash of his challenge */
+ octet hc[MAXHASHSZ]; /* Hash of his challenge */
mp *ck; /* The check value */
- octet hswrq_in[HASHSZ]; /* Inbound switch request message */
- octet hswok_in[HASHSZ]; /* Inbound switch confirmation */
- octet hswrq_out[HASHSZ]; /* Outbound switch request message */
- octet hswok_out[HASHSZ]; /* Outbound switch confirmation */
+ octet hswrq_in[MAXHASHSZ]; /* Inbound switch request message */
+ octet hswok_in[MAXHASHSZ]; /* Inbound switch confirmation */
+ octet hswrq_out[MAXHASHSZ]; /* Outbound switch request message */
+ octet hswok_out[MAXHASHSZ]; /* Outbound switch confirmation */
} kxchal;
typedef struct keyexch {
unsigned f; /* Various useful flags */
unsigned s; /* Current state in exchange */
sel_timer t; /* Timer for next exchange */
- dh_pub kpub; /* Peer's public key */
+ ge *kpub; /* Peer's public key */
time_t texp_kpub; /* Expiry time for public key */
mp *alpha; /* My temporary secret */
- mp *c; /* My challenge */
- mp *rx; /* The expected response */
+ ge *c; /* My challenge */
+ ge *rx; /* The expected response */
unsigned nr; /* Number of extant responses */
time_t t_valid; /* When this exchange goes bad */
- octet hc[HASHSZ]; /* Hash of my challenge */
+ octet hc[MAXHASHSZ]; /* Hash of my challenge */
kxchal *r[KX_NCHAL]; /* Array of challenges */
} keyexch;
* Used to maintain system-specific information about the tunnel interface.
*/
-typedef struct tunnel {
-#if TUN_TYPE == TUN_UNET
- sel_file f; /* Selector for Usernet device */
- struct peer *p; /* Pointer to my peer */
-#elif TUN_TYPE == TUN_LINUX
- sel_file f; /* Selector for TUN/TAP device */
- struct peer *p; /* Pointer to my peer */
- char ifn[IFNAMSIZ]; /* Interface name buffer */
-#elif TUN_TYPE == TUN_BSD
- sel_file f; /* Selector for tunnel device */
- struct peer *p; /* Pointer to my peer */
- unsigned n; /* Number of my tunnel device */
-#else
-# error "No support for this tunnel type"
+typedef struct tunnel tunnel;
+struct peer;
+
+typedef struct tunnel_ops {
+ const char *name; /* Name of this tunnel driver */
+ void (*init)(void); /* Initializes the system */
+ tunnel *(*create)(struct peer */*p*/); /* Initializes a new tunnel */
+ const char *(*ifname)(tunnel */*t*/); /* Returns tunnel's interface name */
+ void (*inject)(tunnel */*t*/, buf */*b*/); /* Sends packet through if */
+ void (*destroy)(tunnel */*t*/); /* Destroys a tunnel */
+} tunnel_ops;
+
+#ifndef TUN_INTERNALS
+struct tunnel { const tunnel_ops *ops; };
#endif
-} tunnel;
/* --- Peer statistics --- *
*
unsigned long sz_in, sz_out; /* Size of all data in and out */
unsigned long sz_kxin, sz_kxout; /* Size of key exchange messages */
unsigned long sz_ipin, sz_ipout; /* Size of encapsulated IP packets */
- time_t t_start, t_last; /* Time peer created, last recv */
+ time_t t_start, t_last, t_kx; /* Time peer created, last pk, kx */
unsigned long n_reject; /* Number of rejected packets */
unsigned long n_in, n_out; /* Number of packets in and out */
unsigned long n_kxin, n_kxout; /* Number of key exchange packets */
typedef struct peer {
struct peer *next, *prev; /* Links to next and previous */
char *name; /* Name of this peer */
- tunnel t; /* Tunnel for local packets */
+ tunnel *t; /* Tunnel for local packets */
keyset *ks; /* List head for keysets */
buf b; /* Buffer for sending packets */
addr peer; /* Peer socket address */
sel_file w; /* Selector for write buffering */
bres_client r; /* Background resolver task */
sel_timer t; /* Timer for resolver */
+ const tunnel_ops *tops; /* Tunnel to use */
addr peer; /* Address to set */
size_t sasz; /* Size of the address */
} admin;
#define AF_DEAD 1u /* Destroy this admin block */
#define AF_LOCK 2u /* Don't destroy it yet */
+#define AF_NOTE 4u /* Catch notifications */
+#ifndef NTRACE
+ #define AF_TRACE 8u /* Catch tracing */
+#endif
+#define AF_WARN 16u /* Catch warning messages */
+
+#ifndef NTRACE
+# define AF_ALLMSGS (AF_NOTE | AF_TRACE | AF_WARN)
+#else
+# define AF_ALLMSGS (AF_NOTE | AF_WARN)
+#endif
/*----- Global variables --------------------------------------------------*/
extern sel_state sel; /* Global I/O event state */
-extern dh_priv kpriv; /* Our private key */
-extern mpmont mg; /* Montgomery context for DH group */
+extern group *gg; /* The group we work in */
+extern mp *kpriv; /* Our private key */
extern octet buf_i[PKBUFSZ], buf_o[PKBUFSZ], buf_t[PKBUFSZ];
+extern const tunnel_ops *tunnels[]; /* Table of tunnels (0-term) */
+extern const tunnel_ops *tun_default; /* Default tunnel to use */
#ifndef NTRACE
extern const trace_opt tr_opts[]; /* Trace options array */
/* --- @km_getpubkey@ --- *
*
* Arguments: @const char *tag@ = public key tag to load
- * @dh_pub *kpub@ = where to put the public key
+ * @ge *kpub@ = where to put the public key
* @time_t *t_exp@ = where to put the expiry time
*
* Returns: Zero if OK, nonzero if it failed.
* Use: Fetches a public key from the keyring.
*/
-extern int km_getpubkey(const char */*tag*/, dh_pub */*kpub*/,
+extern int km_getpubkey(const char */*tag*/, ge */*kpub*/,
time_t */*t_exp*/);
/*----- Key exchange ------------------------------------------------------*/
*
* Arguments: @const void *k@ = pointer to key material
* @size_t x, y, z@ = offsets into key material (see below)
+ * @peer *p@ = pointer to peer information
*
* Returns: A pointer to the new keyset.
*
*/
extern keyset *ks_gen(const void */*k*/,
- size_t /*x*/, size_t /*y*/, size_t /*z*/);
+ size_t /*x*/, size_t /*y*/, size_t /*z*/,
+ peer */*p*/);
/* --- @ks_tregen@ --- *
*
/* --- @ks_encrypt@ --- *
*
* Arguments: @keyset *ks@ = pointer to a keyset
+ * @unsigned ty@ = message type
* @buf *b@ = pointer to input buffer
* @buf *bb@ = pointer to output buffer
*
* used even if it's marked as not for data output.
*/
-extern int ks_encrypt(keyset */*ks*/, buf */*b*/, buf */*bb*/);
+extern int ks_encrypt(keyset */*ks*/, unsigned /*ty*/,
+ buf */*b*/, buf */*bb*/);
/* --- @ks_decrypt@ --- *
*
* Arguments: @keyset *ks@ = pointer to a keyset
+ * @unsigned ty@ = expected type code
* @buf *b@ = pointer to an input buffer
* @buf *bb@ = pointer to an output buffer
*
* marking that it's not for encryption.
*/
-extern int ks_decrypt(keyset */*ks*/, buf */*b*/, buf */*bb*/);
+extern int ks_decrypt(keyset */*ks*/, unsigned /*ty*/,
+ buf */*b*/, buf */*bb*/);
/* --- @ksl_free@ --- *
*
/* --- @ksl_encrypt@ --- *
*
* Arguments: @keyset **ksroot@ = pointer to keyset list head
+ * @unsigned ty@ = message type
* @buf *b@ = pointer to input buffer
* @buf *bb@ = pointer to output buffer
*
* Use: Encrypts a packet.
*/
-extern int ksl_encrypt(keyset **/*ksroot*/, buf */*b*/, buf */*bb*/);
+extern int ksl_encrypt(keyset **/*ksroot*/, unsigned /*ty*/,
+ buf */*b*/, buf */*bb*/);
/* --- @ksl_decrypt@ --- *
*
* Arguments: @keyset **ksroot@ = pointer to keyset list head
+ * @unsigned ty@ = expected type code
* @buf *b@ = pointer to input buffer
* @buf *bb@ = pointer to output buffer
*
* Use: Decrypts a packet.
*/
-extern int ksl_decrypt(keyset **/*ksroot*/, buf */*b*/, buf */*bb*/);
+extern int ksl_decrypt(keyset **/*ksroot*/, unsigned /*ty*/,
+ buf */*b*/, buf */*bb*/);
/*----- Administration interface ------------------------------------------*/
extern void a_warn(const char */*fmt*/, ...);
+/* --- @a_notify@ --- *
+ *
+ * Arguments: @const char *fmt@ = pointer to format string
+ * @...@ = other arguments
+ *
+ * Returns: ---
+ *
+ * Use: Sends a notification to interested admin connections.
+ */
+
+extern void a_notify(const char */*fmt*/, ...);
+
/* --- @a_create@ --- *
*
* Arguments: @int fd_in, fd_out@ = file descriptors to use
+ * @unsigned f@ = initial flags to set
*
* Returns: ---
*
* Use: Creates a new admin connection.
*/
-extern void a_create(int /*fd_in*/, int /*fd_out*/);
+extern void a_create(int /*fd_in*/, int /*fd_out*/, unsigned /*f*/);
/* --- @a_quit@ --- *
*
/* --- @p_init@ --- *
*
- * Arguments: @unsigned port@ = port number to listen to
+ * Arguments: @struct in_addr addr@ = address to bind to
+ * @unsigned port@ = port number to listen to
*
* Returns: ---
*
* Use: Initializes the peer system; creates the socket.
*/
-extern void p_init(unsigned /*port*/);
+extern void p_init(struct in_addr /*addr*/, unsigned /*port*/);
/* --- @p_port@ --- *
*
/* --- @p_create@ --- *
*
* Arguments: @const char *name@ = name for this peer
+ * @const tunnel_ops *tops@ = tunnel to use
* @struct sockaddr *sa@ = socket address of peer
* @size_t sz@ = size of socket address
*
* by this point.
*/
-extern peer *p_create(const char */*name*/,
+extern peer *p_create(const char */*name*/, const tunnel_ops */*tops*/,
struct sockaddr */*sa*/, size_t /*sz*/);
/* --- @p_name@ --- *
extern peer *p_first(void);
extern peer *p_next(peer */*p*/);
-/*----- Tunnel interface --------------------------------------------------*/
-
-/* --- @tun_init@ --- *
- *
- * Arguments: ---
- *
- * Returns: ---
- *
- * Use: Initializes the tunneling system. Maybe this will require
- * opening file descriptors or something.
- */
-
-extern void tun_init(void);
-
-/* --- @tun_create@ --- *
- *
- * Arguments: @tunnel *t@ = pointer to tunnel block
- * @peer *p@ = pointer to peer block
- *
- * Returns: Zero if it worked, nonzero on failure.
- *
- * Use: Initializes a new tunnel.
- */
-
-extern int tun_create(tunnel */*t*/, peer */*p*/);
-
-/* --- @tun_ifname@ --- *
- *
- * Arguments: @tunnel *t@ = pointer to tunnel block
- *
- * Returns: A pointer to the tunnel's interface name.
- */
+/*----- Tunnel drivers ----------------------------------------------------*/
-extern const char *tun_ifname(tunnel */*t*/);
-
-/* --- @tun_inject@ --- *
- *
- * Arguments: @tunnel *t@ = pointer to tunnel block
- * @buf *b@ = buffer to send
- *
- * Returns: ---
- *
- * Use: Injects a packet into the local network stack.
- */
+#ifdef TUN_LINUX
+ extern const tunnel_ops tun_linux;
+#endif
-extern void tun_inject(tunnel */*t*/, buf */*b*/);
+#ifdef TUN_UNET
+ extern const tunnel_ops tun_unet;
+#endif
-/* --- @tun_destroy@ --- *
- *
- * Arguments: @tunnel *t@ = pointer to tunnel block
- *
- * Returns: ---
- *
- * Use: Destroys a tunnel.
- */
+#ifdef TUN_BSD
+ extern const tunnel_ops tun_bsd;
+#endif
-extern void tun_destroy(tunnel */*t*/);
+extern const tunnel_ops tun_slip;
/*----- Other handy utilities ---------------------------------------------*/
extern const char *mpstr(mp */*m*/);
+/* --- @gestr@ --- *
+ *
+ * Arguments: @group *g@ = a group
+ * @ge *x@ = a group element
+ *
+ * Returns: A pointer to the element's textual representation.
+ *
+ * Use: Converts a group element to a string. Corrupts
+ * @buf_t@.
+ */
+
+extern const char *gestr(group */*g*/, ge */*x*/);
+
/* --- @timestr@ --- *
*
* Arguments: @time_t t@ = a time to convert
extern const char *timestr(time_t /*t*/);
+/* --- @mystrieq@ --- *
+ *
+ * Arguments: @const char *x, *y@ = two strings
+ *
+ * Returns: True if @x@ and @y are equal, up to case.
+ */
+
+extern int mystrieq(const char */*x*/, const char */*y*/);
+
/*----- That's all, folks -------------------------------------------------*/
#ifdef __cplusplus
~mdw / tripe / blobdiff