*
* This file is part of Trivial IP Encryption (TrIPE).
*
- * TrIPE is free software; you can redistribute it and/or modify
- * it under the terms of the GNU General Public License as published by
- * the Free Software Foundation; either version 2 of the License, or
- * (at your option) any later version.
+ * TrIPE is free software: you can redistribute it and/or modify it under
+ * the terms of the GNU General Public License as published by the Free
+ * Software Foundation; either version 3 of the License, or (at your
+ * option) any later version.
*
- * TrIPE is distributed in the hope that it will be useful,
- * but WITHOUT ANY WARRANTY; without even the implied warranty of
- * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
- * GNU General Public License for more details.
+ * TrIPE is distributed in the hope that it will be useful, but WITHOUT
+ * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or
+ * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License
+ * for more details.
*
* You should have received a copy of the GNU General Public License
- * along with TrIPE; if not, write to the Free Software Foundation,
- * Inc., 59 Temple Place - Suite 330, Boston, MA 02111-1307, USA.
+ * along with TrIPE. If not, see <https://www.gnu.org/licenses/>.
*/
#ifndef TRIPE_H
#include <mLib/arena.h>
#include <mLib/base64.h>
#include <mLib/bres.h>
+#include <mLib/codec.h>
#include <mLib/daemonize.h>
#include <mLib/dstr.h>
#include <mLib/env.h>
#include <catacomb/buf.h>
#include <catacomb/ct.h>
+#include <catacomb/chacha.h>
#include <catacomb/gcipher.h>
#include <catacomb/gmac.h>
#include <catacomb/grand.h>
#include <catacomb/key.h>
#include <catacomb/paranoia.h>
+#include <catacomb/poly1305.h>
+#include <catacomb/salsa20.h>
#include <catacomb/noise.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-raw.h>
#include <catacomb/ec-keys.h>
-#include <catacomb/group.h>
+#include <catacomb/x25519.h>
+#include <catacomb/x448.h>
#include "priv.h"
#include "protocol.h"
typedef struct keyset keyset;
typedef struct algswitch algswitch;
+typedef struct kdata kdata;
+typedef struct admin admin;
-typedef struct bulkcrypto {
+typedef struct dhgrp {
+ const struct dhops *ops;
+ size_t scsz;
+} dhgrp;
+
+typedef struct dhsc dhsc;
+typedef struct dhge dhge;
+
+enum {
+ DHFMT_STD, /* Fixed-width format, suitable for encryption */
+ DHFMT_HASH, /* Deterministic format, suitable for hashing */
+ DHFMT_VAR /* Variable-width-format, mostly a bad idea */
+};
+
+typedef struct bulkalgs {
+ const struct bulkops *ops;
+} bulkalgs;
+
+typedef struct bulkctx {
+ const struct bulkops *ops;
+} bulkctx;
+
+typedef struct bulkchal {
+ const struct bulkops *ops;
+ size_t tagsz;
+} bulkchal;
+
+struct rawkey;
+
+typedef struct dhops {
+ const char *name;
+
+ int (*ldpriv)(key_file */*kf*/, key */*k*/, key_data */*d*/,
+ kdata */*kd*/, dstr */*t*/, dstr */*e*/);
+ /* Load a private key from @d@, storing the data in @kd@. The key's
+ * file and key object are in @kf@ and @k@, mostly in case its
+ * attributes are interesting; the key tag is in @t@; errors are
+ * reported by writing tokens to @e@ and returning nonzero.
+ */
+
+ int (*ldpub)(key_file */*kf*/, key */*k*/, key_data */*d*/,
+ kdata */*kd*/, dstr */*t*/, dstr */*e*/);
+ /* Load a public key from @d@, storing the data in @kd@. The key's
+ * file and key object are in @kf@ and @k@, mostly in case its
+ * attributes are interesting; the key tag is in @t@; errors are
+ * reported by writing tokens to @e@ and returning nonzero.
+ */
+
+ const char *(*checkgrp)(const dhgrp */*g*/);
+ /* Check that the group is valid; return null on success, or an error
+ * string.
+ */
+
+ void (*grpinfo)(const dhgrp */*g*/, admin */*a*/);
+ /* Report on the group to an admin client. */
+
+ T( void (*tracegrp)(const dhgrp */*g*/); )
+ /* Trace a description of the group. */
+
+ int (*samegrpp)(const dhgrp */*g*/, const dhgrp */*gg*/);
+ /* Return nonzero if the two group objects represent the same
+ * group.
+ */
+
+ void (*freegrp)(dhgrp */*g*/);
+ /* Free a group and the resources it holds. */
+
+ dhsc *(*ldsc)(const dhgrp */*g*/, const void */*p*/, size_t /*sz*/);
+ /* Load a scalar from @p@, @sz@ and return it. Return null on
+ * error.
+ */
+
+ int (*stsc)(const dhgrp */*g*/,
+ void */*p*/, size_t /*sz*/, const dhsc */*x*/);
+ /* Store a scalar at @p@, @sz@. Return nonzero on error. */
+
+ dhsc *(*randsc)(const dhgrp */*g*/);
+ /* Return a random scalar. */
+
+ T( const char *(*scstr)(const dhgrp */*g*/, const dhsc */*x*/); )
+ /* Return a human-readable representation of @x@; @buf_t@ may be used
+ * to hold it.
+ */
+
+ void (*freesc)(const dhgrp */*g*/, dhsc */*x*/);
+ /* Free a scalar and the resources it holds. */
+
+ dhge *(*ldge)(const dhgrp */*g*/, buf */*b*/, int /*fmt*/);
+ /* Load a group element from @b@, encoded using format @fmt@. Return
+ * null on error.
+ */
+
+ int (*stge)(const dhgrp */*g*/, buf */*b*/,
+ const dhge */*Y*/, int /*fmt*/);
+ /* Store a group element in @b@, encoded using format @fmt@. Return
+ * nonzero on error.
+ */
+
+ int (*checkge)(const dhgrp */*h*/, const dhge */*Y*/);
+ /* Check a group element for validity. Return zero if everything
+ * checks out; nonzero on failure.
+ */
+
+ int (*eq)(const dhgrp */*g*/, const dhge */*Y*/, const dhge */*Z*/);
+ /* Return nonzero if @Y@ and @Z@ are equal. */
+
+ dhge *(*mul)(const dhgrp */*g*/, const dhsc */*x*/, const dhge */*Y*/);
+ /* Multiply a group element by a scalar, resulting in a shared-secret
+ * group element. If @y@ is null, then multiply the well-known
+ * generator.
+ */
+
+ T( const char *(*gestr)(const dhgrp */*g*/, const dhge */*Y*/); )
+ /* Return a human-readable representation of @Y@; @buf_t@ may be used
+ * to hold it.
+ */
+
+ void (*freege)(const dhgrp */*g*/, dhge */*Y*/);
+ /* Free a group element and the resources it holds. */
+
+} dhops;
+
+typedef struct bulkops {
const char *name;
- unsigned prim;
- int (*check)(const algswitch */*a*/, dstr */*e*/);
- size_t (*overhead)(const algswitch */*a*/);
- int (*encrypt)(keyset */*ks*/, unsigned /*ty*/, buf */*b*/, buf */*bb*/);
- int (*decrypt)(keyset */*ks*/, unsigned /*ty*/,
+
+ bulkalgs *(*getalgs)(const algswitch */*asw*/, dstr */*e*/,
+ key_file */*kf*/, key */*k*/);
+ /* Determine algorithms to use and return a @bulkalgs@ object
+ * representing the decision. On error, write tokens to @e@ and
+ * return null.
+ */
+
+ T( void (*tracealgs)(const bulkalgs */*a*/); )
+ /* Write trace information about the algorithm selection. */
+
+ int (*checkalgs)(bulkalgs */*a*/, const algswitch */*asw*/, dstr */*e*/);
+ /* Check that the algorithms in @a@ and @asw@ are acceptable. On
+ * error, write tokens to @e@ and return @-1@; otherwise return zero.
+ */
+
+ int (*samealgsp)(const bulkalgs */*a*/, const bulkalgs */*aa*/);
+ /* If @a@ and @aa@ represent the same algorithm selection, return
+ * nonzero; if not, return zero.
+ */
+
+ void (*alginfo)(const bulkalgs */*a*/, admin */*adm*/);
+ /* Report on the algorithm selection to an admin client: call
+ * @a_info@ with appropriate key-value pairs.
+ */
+
+ size_t (*overhead)(const bulkalgs */*a*/);
+ /* Return the per-packet overhead of the bulk transform, in bytes. */
+
+ size_t (*expsz)(const bulkalgs */*a*/);
+ /* Return the total size limit for the bulk transform, in bytes,
+ * after which the keys must no longer be used.
+ */
+
+ bulkctx *(*genkeys)(const bulkalgs */*a*/, const struct rawkey */*rk*/);
+ /* Generate session keys and construct and return an appropriate
+ * context for using them, by calling @ks_derive@.
+ */
+
+ bulkchal *(*genchal)(const bulkalgs */*a*/);
+ /* Construct and return a challenge issuing and verification
+ * context with a fresh random key.
+ */
+
+ void (*freealgs)(bulkalgs */*a*/);
+ /* Release an algorithm selection object. (Associated bulk
+ * encryption contexts and challenge contexts may still exist and
+ * must remain valid.)
+ */
+
+ int (*encrypt)(bulkctx */*bc*/, unsigned /*ty*/,
+ buf */*b*/, buf */*bb*/, uint32 /*seq*/);
+ /* Encrypt the packet in @b@, with type @ty@ (which doesn't need
+ * encoding separately) and sequence number @seq@ (which must be
+ * recoverable by @decrypt@), and write the result to @bb@. On
+ * error, return a @KSERR_...@ code and/or break the output buffer.
+ */
+
+ int (*decrypt)(bulkctx */*bc*/, unsigned /*ty*/,
buf */*b*/, buf */*bb*/, uint32 */*seq*/);
-} bulkcrypto;
+ /* Decrypt the packet in @b@, with type @ty@, writing the result to
+ * @bb@ and storing the incoming (claimed) sequence number in @seq@.
+ * On error, return a @KSERR_...@ code.
+ */
+
+ void (*freectx)(bulkctx */*a*/);
+ /* Release a bulk encryption context and the resources it holds. */
+
+ int (*chaltag)(bulkchal */*bc*/, const void */*m*/, size_t /*msz*/,
+ void */*t*/);
+ /* Calculate a tag for the challenge in @m@, @msz@, and write it to
+ * @t@. Return @-1@ on error, zero on success.
+ */
+
+ int (*chalvrf)(bulkchal */*bc*/, const void */*m*/, size_t /*msz*/,
+ const void */*t*/);
+ /* Check the tag @t@ on @m@, @msz@: return zero if the tag is OK,
+ * nonzero if it's bad.
+ */
+
+ void (*freechal)(bulkchal */*bc*/);
+ /* Release a challenge context and the resources it holds. */
-#define BCP_CIPHER 1
-#define BCP_MAC 2
-#define BCP_BLKC 4
+} bulkops;
struct algswitch {
- const gchash *h; /* Hash function */
+ const gchash *h; size_t hashsz; /* Hash function */
const gccipher *mgf; /* Mask-generation function */
- const bulkcrypto *bulk; /* Bulk crypto transformation */
- const gccipher *c; /* Symmetric encryption scheme */
- const gcmac *m; /* Message authentication code */
- const gccipher *b; /* Block cipher */
- size_t hashsz; /* Hash output size */
- size_t tagsz; /* Length to truncate MAC tags */
- size_t expsz; /* Size of data to process */
- size_t cksz, mksz, bksz; /* Key lengths for things */
+ bulkalgs *bulk; /* Bulk crypto algorithms */
};
-typedef struct kdata {
+struct kdata {
unsigned ref; /* Reference counter */
struct knode *kn; /* Pointer to cache entry */
char *tag; /* Full tag name of the key */
- group *g; /* The group we work in */
- size_t indexsz; /* Size of exponent for the group */
- mp *kpriv; /* The private key (or null) */
- ge *kpub; /* The public key */
+ dhgrp *grp; /* The group we work in */
+ dhsc *k; /* The private key (or null) */
+ dhge *K; /* The public key */
time_t t_exp; /* Expiry time of the key */
algswitch algs; /* Collection of algorithms */
-} kdata;
+};
typedef struct knode {
sym_base _b; /* Symbol table intrusion */
#define HASH_STRING(h, s) GH_HASH((h), (s), sizeof(s))
-extern const bulkcrypto bulktab[];
+extern const dhops dhtab[];
+extern const bulkops bulktab[];
/*----- Data structures ---------------------------------------------------*/
* expiry.
*/
+enum { DIR_IN, DIR_OUT, NDIR };
+
struct keyset {
struct keyset *next; /* Next active keyset in the list */
unsigned ref; /* Reference count for keyset */
unsigned long sz_exp, sz_regen; /* Data limits for the keyset */
T( unsigned seq; ) /* Sequence number for tracing */
unsigned f; /* Various useful flags */
- const bulkcrypto *bulk; /* Bulk crypto transform */
- size_t tagsz; /* Length to truncate MAC tags */
- struct ksdir {
- gcipher *c; /* Keyset cipher for encryption */
- gmac *m; /* Keyset MAC for integrity */
- gcipher *b; /* Block cipher, just in case */
- } in, out;
+ bulkctx *bulk; /* Bulk crypto transform */
uint32 oseq; /* Outbound sequence number */
seqwin iseq; /* Inbound sequence number */
};
typedef struct kxchal {
struct keyexch *kx; /* Pointer back to key exchange */
- ge *c; /* Responder's challenge */
- ge *r; /* My reply to the challenge */
+ dhge *C; /* Responder's challenge */
+ dhge *R; /* My reply to the challenge */
keyset *ks; /* Pointer to temporary keyset */
unsigned f; /* Various useful flags */
sel_timer t; /* Response timer for challenge */
unsigned s; /* Current state in exchange */
sel_timer t; /* Timer for next exchange */
retry rs; /* Retry state */
- mp *alpha; /* My temporary secret */
- ge *c; /* My challenge */
- ge *rx; /* The expected response */
+ dhsc *a; /* My temporary secret */
+ dhge *C; /* My challenge */
+ dhge *RX; /* The expected response */
unsigned nr; /* Number of extant responses */
time_t t_valid; /* When this exchange goes bad */
octet hc[MAXHASHSZ]; /* Hash of my challenge */
const tunnel_ops *tops; /* Tunnel operations */
unsigned long t_ka; /* Keep alive interval */
addr sa; /* Socket address to speak to */
- size_t sasz; /* Socket address size */
unsigned f; /* Flags for the peer */
#define PSF_KXMASK 255u /* Key-exchange flags to set */
#define PSF_MOBILE 256u /* Address may change rapidly */
admin_jobentry *v; /* And the big array of entries */
} admin_jobtable;
-typedef struct admin {
+struct admin {
struct admin *next, *prev; /* Links to next and previous */
unsigned f; /* Various useful flags */
unsigned ref; /* Reference counter */
admin_jobtable j; /* Table of outstanding jobs */
selbuf b; /* Line buffer for commands */
sel_file w; /* Selector for write buffering */
-} admin;
+};
#define AF_DEAD 1u /* Destroy this admin block */
#define AF_CLOSE 2u /* Client closed connection */
#define AF_NOTE 4u /* Catch notifications */
#define AF_WARN 8u /* Catch warning messages */
#ifndef NTRACE
- #define AF_TRACE 16u /* Catch tracing */
+# define AF_TRACE 16u /* Catch tracing */
#endif
#define AF_FOREGROUND 32u /* Quit server when client closes */
extern void ks_drop(keyset */*ks*/);
+/* --- @ks_derivekey@ --- *
+ *
+ * Arguments: @octet *k@ = pointer to an output buffer of at least
+ * @MAXHASHSZ@ bytes
+ * @size_t ksz@ = actual size wanted (for tracing)
+ * @const struct rawkey *rk@ = a raw key, as passed into
+ * @genkeys@
+ * @int dir@ = direction for the key (@DIR_IN@ or @DIR_OUT@)
+ * @const char *what@ = label for the key (input to derivation)
+ *
+ * Returns: ---
+ *
+ * Use: Derives a session key, for use on incoming or outgoing data.
+ * This function is part of a private protocol between @ks_gen@
+ * and the bulk crypto transform @genkeys@ operation.
+ */
+
+extern void ks_derivekey(octet */*k*/, size_t /*ksz*/,
+ const struct rawkey */*rk*/,
+ int /*dir*/, const char */*what*/);
+
/* --- @ks_gen@ --- *
*
* Arguments: @const void *k@ = pointer to key material
* the key material; between @k + x@ and @k + y@ is `your'
* contribution; and between @k + y@ and @k + z@ is a shared
* value we made together. These are used to construct two
- * pairs of symmetric keys. Each pair consists of an encryption
- * key and a message authentication key. One pair is used for
- * outgoing messages, the other for incoming messages.
+ * collections of symmetric keys: one for outgoing messages, the
+ * other for incoming messages.
*
* The new key is marked so that it won't be selected for output
* by @ksl_encrypt@. You can still encrypt data with it by
extern void EXECL_LIKE(0) a_format(dstr */*d*/, const char */*fmt*/, ...);
+/* --- @a_info@ --- *
+ *
+ * Arguments: @admin *a@ = connection
+ * @const char *fmt@ = format string
+ * @...@ = other arguments
+ *
+ * Returns: ---
+ *
+ * Use: Report information to an admin client.
+ */
+
+extern void EXECL_LIKE(0) a_info(admin */*a*/, const char */*fmt*/, ...);
+
/* --- @a_warn@ --- *
*
* Arguments: @const char *fmt@ = pointer to format string
/*----- Peer management ---------------------------------------------------*/
+/* --- @p_updateaddr@ --- *
+ *
+ * Arguments: @peer *p@ = pointer to peer block
+ * @const addr *a@ = address to associate with this peer
+ *
+ * Returns: Zero if the address was changed; @+1@ if it was already
+ * right.
+ *
+ * Use: Updates our idea of @p@'s address.
+ */
+
+extern int p_updateaddr(peer */*p*/, const addr */*a*/);
+
/* --- @p_txstart@ --- *
*
* Arguments: @peer *p@ = pointer to peer block
/*----- Other handy utilities ---------------------------------------------*/
-/* --- @mpstr@ --- *
- *
- * Arguments: @mp *m@ = a multiprecision integer
- *
- * Returns: A pointer to the integer's textual representation.
- *
- * Use: Converts a multiprecision integer to a string. Corrupts
- * @buf_u@.
- */
-
-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_u@.
- */
-
-extern const char *gestr(group */*g*/, ge */*x*/);
-
/* --- @timestr@ --- *
*
* Arguments: @time_t t@ = a time to convert
extern int mystrieq(const char */*x*/, const char */*y*/);
+/* --- @addrsz@ --- *
+ *
+ * Arguments: @const addr *a@ = a network address
+ *
+ * Returns: The size of the address, for passing into the sockets API.
+ */
+
+extern socklen_t addrsz(const addr */*a*/);
+
/* --- @seq_reset@ --- *
*
* Arguments: @seqwin *s@ = sequence-checking window