An actually working handshake example in a main().

src/crypt.c

@@ -198,5 +198,5 @@ void crypt_session_destroy(crypt_session_t *const s) {
     sodium_memzero(s->rx, CRYPT_SESS_KEY_LEN);
     sodium_memzero(s->tx, CRYPT_SESS_KEY_LEN);
     sodium_memzero(s->nonce, CRYPT_NONCE_LEN);
-    crypt_key_destroy(s->remote_key);
+    s->remote_key = NULL;
 }

src/main.c

@@ -4,7 +4,6 @@
 #include <stdio.h>
 #include <string.h>
 #include <sys/types.h>
-#include <errno.h>
 
 // #include "audio.h"
 #include "crypt.h"
@@ -20,12 +19,12 @@ int main(int argc, char **argv) {
     (void)argv;
     (void)argc;
 
-    crypt_key_t kl, kr;
-    unsigned char *hl, *hr;
+    crypt_key_t kl = {0}, kr = {0};
+    unsigned char *hl = NULL, *hr = NULL;
     unsigned char hlr[CRYPT_HELLO_LEN], hrl[CRYPT_HELLO_LEN];
-    unsigned char *nonce;
-    net_t nl, nr;
-    crypt_session_t sl, sr;
+    unsigned char *nonce = NULL;
+    net_t nl = {0}, nr = {0};
+    crypt_session_t sl = {0}, sr = {0};
 
     const int incom_len = 512;
     char incom[incom_len];
@@ -78,29 +77,14 @@ int main(int argc, char **argv) {
         goto cleanup;
     }
 
-    if (rcvd == CRYPT_HELLO_LEN) {
-        memcpy(hrl, incom, CRYPT_HELLO_LEN);
-    }
-
-    sent = net_send(&nl, (const char *)hl, CRYPT_HELLO_LEN);
-    if (sent == -1) {
-        ret = -1;
-        goto cleanup;
-    }
-
-    rcvd = net_recv(&nr, incom, incom_len);
-    if (rcvd == -1) {
-        ret = -1;
-        goto cleanup;
-    }
-    // fprintf(stderr, "%s:%d\n", __FILE__, __LINE__);
+    nr.raddr = nr.inaddr;
+    nr.raddr_len = nr.inaddr_len;
 
     if (rcvd == CRYPT_HELLO_LEN) {
         memcpy(hrl, incom, CRYPT_HELLO_LEN);
-        nr.raddr = nr.inaddr;
-        nr.raddr_len = nr.inaddr_len;
     } else {
-        fprintf(stderr, "A broken hello packet was received.");
+        fprintf(stderr, "remote: A broken hello packet was received.");
+        net_send(&nr, "FUCKOFF", 7);
         ret = -1;
         goto cleanup;
     }
@@ -116,28 +100,43 @@ int main(int argc, char **argv) {
         ret = -1;
         goto cleanup;
     }
-    // fprintf(stderr, "%s:%d\n", __FILE__, __LINE__);
 
     if (rcvd == CRYPT_HELLO_LEN) {
         memcpy(hlr, incom, CRYPT_HELLO_LEN);
-        nl.raddr = nl.inaddr;
-        nl.raddr_len = nl.inaddr_len;
     } else {
-        fprintf(stderr, "A broken hello packet was received.");
+        if (memcmp("FUCKOFF", incom, 7) == 0) {
+            fprintf(stderr, "local: A broken hello packet was sent by me.");
+        } else {
+            fprintf(stderr, "local: A broken hello packet was received.");
+            net_send(&nl, "FUCKOFF", 7);
+        }
+
         ret = -1;
         goto cleanup;
     }
 
     if (crypt_hello_verify(hlr, &kr) == -1) {
         fprintf(stderr, "hello remote -> local: not verified\n");
+        net_send(&nl, "FUCKOFF", 7);
+        ret = -1;
+        goto cleanup;
+    } else {
+        net_send(&nl, "YOU'RE WELCOME", 14);
+    }
+
+    rcvd = net_recv(&nr, incom, incom_len);
+    if (rcvd == -1) {
         ret = -1;
         goto cleanup;
     }
 
     if (crypt_hello_verify(hrl, &kl) == -1) {
         fprintf(stderr, "hello local -> remote: not verified\n");
+        net_send(&nr, "FUCKOFF", 7);
         ret = -1;
         goto cleanup;
+    } else {
+        net_send(&nr, "YOU'RE WELCOME", 14);
     }
 
     nonce = crypt_hello_get_nonce(hl, hlr, true);
@@ -150,6 +149,8 @@ int main(int argc, char **argv) {
         goto cleanup;
     }
 
+    free(rn);
+
     if (crypt_session_init(&sl, &kl, &kr, nonce, true) == -1) {
         fprintf(stderr, "local session init fail\n");
         ret = -1;

src/net.c

@@ -33,6 +33,7 @@ int net_client_init(net_t *const n, const char *const raddr, const char *const r
 
     memset(&n->raddr, 0, sizeof(n->raddr));
     memcpy(&n->raddr, cri->ai_addr, sizeof(n->raddr));
+    n->raddr_len = sizeof(n->raddr);
 
     freeaddrinfo(ri);
 
@@ -69,9 +70,10 @@ int net_server_init(net_t *const n, const char *const laddr, const char *const l
     }
 
     memset(&n->inaddr, 0, sizeof(n->inaddr));
-    n->inaddr_len = 0;
+    n->inaddr_len = sizeof(n->inaddr);
 
     memset(&n->raddr, 0, sizeof(n->raddr));
+    n->raddr_len = sizeof(n->raddr);
 
     memset(&n->laddr, 0, sizeof(n->laddr));
     memcpy(&n->laddr, cli->ai_addr, sizeof(n->raddr));
@@ -88,10 +90,10 @@ void net_destroy(net_t *n) {
     }
 
     memset(&n->raddr, 0, sizeof(n->raddr));
-    n->raddr_len = 0;
+    n->raddr_len = sizeof(n->raddr);
     memset(&n->laddr, 0, sizeof(n->laddr));
     memset(&n->inaddr, 0, sizeof(n->inaddr));
-    n->inaddr_len = 0;
+    n->inaddr_len = sizeof(n->inaddr);
 }
 
 ssize_t net_send(net_t *const n, const char *const buf, int buf_len) {