In net_send() check if an raddr struct is set.

src/crypt.h

@@ -22,7 +22,6 @@
 #define CRYPT_PKEY_HEXLEN ((CRYPT_KX_PKEY_LEN + CRYPT_SIGN_PKEY_LEN) * 2)
 #define CRYPT_SKEY_HEXLEN ((CRYPT_SIGN_PKEY_LEN + CRYPT_SIGN_SKEY_LEN) * 2)
 
-// Stores the public and secret keys used in a key exchange and for signing.
 typedef struct crypt_key_t {
     unsigned char kx_pub[crypto_kx_PUBLICKEYBYTES];
     unsigned char kx_sec[crypto_kx_SECRETKEYBYTES];
@@ -31,39 +30,21 @@ typedef struct crypt_key_t {
     bool hasSecKey;
 } crypt_key_t;
 
-// Generates the new pairs of a key exchange and sign keys.
 int crypt_key_gen(crypt_key_t *const k);
-// Initialise a crypt_key_t with a provided hex representaions of public and secret keys.
 int crypt_key_from_hex(crypt_key_t *const k, const char phex[CRYPT_PKEY_HEXLEN], const char shex[CRYPT_SKEY_HEXLEN]);
-// Initialise a crypt_key_t with a provided hex representaion of just a public key. Used for remote keys.
 int crypt_key_from_hex_public(crypt_key_t *const k, const char phex[CRYPT_PKEY_HEXLEN]);
-
-// Securely erase the fields of a crypt_key_t struct.
 void crypt_key_destroy(crypt_key_t *const k);
 
-// Export a public sign and key exchange keys as a hex string.
 int crypt_key_export_public(const crypt_key_t *const k, char hex[CRYPT_PKEY_HEXLEN]);
-// Export a secret sign and key exchange keys as a hex string.
 int crypt_key_export_secret(const crypt_key_t *const k, char hex[CRYPT_SKEY_HEXLEN]);
 
-// Load the sign and key exchange keys in a hex representaion from files
-// and initialise a crypt_key_t.
 int crypt_load_key(crypt_key_t *const k, FILE *const pub, FILE *const sec);
-// Store a hex representaion of the sign and key exchange keys into files
-// that are corresponding to a public and a secret parts.
 int crypt_store_key(const crypt_key_t *const k, FILE *const pub, FILE *const sec);
 
-// Returns a hello packet consisting of a public key and its sign.
-// The packet is of CRYPT_SIGN_LEN long.
 unsigned char *crypt_hello(const crypt_key_t *const own);
-// Verify a hello message. It only shows that a remote public key's sign is ok.
 int crypt_hello_verify(const unsigned char *const hello, crypt_key_t *const remote);
-// Combines own and remote halves of a nonce depending in a connection direction and returns it.
-// It will be of CRYPT_NONCE_LEN length.
 unsigned char *crypt_hello_get_nonce(const unsigned char *const own_hello, const unsigned char *const remote_hello, bool is_client);
 
-// Stores symmetric keys used for a data encryption in both directions
-// and a remote public key.
 typedef struct crypt_session_t {
     unsigned char rx[CRYPT_SESS_KEY_LEN];
     unsigned char tx[CRYPT_SESS_KEY_LEN];
@@ -71,13 +52,9 @@ typedef struct crypt_session_t {
     crypt_key_t *remote_key;
 } crypt_session_t;
 
-// Derives the symmetric keys for a data encryption using own public and secret and remote's public keys.
-//
-// is_client should be set to true if you are the one establishing the connection.
 int crypt_session_init(crypt_session_t *const s, const crypt_key_t *const own, crypt_key_t *const remote, const unsigned char *const nonce, bool is_client);
 unsigned char *crypt_session_encrypt(crypt_session_t *const s, const unsigned char *const m, unsigned long long mlen, unsigned long long *clen);
 unsigned char *crypt_session_decrypt(crypt_session_t *const s, const unsigned char *const c, unsigned long long clen, unsigned long long *mlen);
-// Securely erase the fields of a crypt_session_t struct.
 void crypt_session_destroy(crypt_session_t *const s);
 
 #endif /* _CRYPT_H_ */

src/net.c

@@ -16,7 +16,6 @@ int net_client_init(net_t *const n, const int af_family, const char *const raddr
     n->raddr.sin_family = af_family;
     n->raddr.sin_addr.s_addr = inet_addr(raddr);
     n->raddr.sin_port = htons(rport);
-
     return 0;
 }
 
@@ -50,12 +49,10 @@ void net_destroy(net_t *n) {
     memset(&n->raddr, 0, sizeof(n->raddr));
     n->raddr_len = sizeof(n->raddr);
     memset(&n->laddr, 0, sizeof(n->laddr));
-
-    memset(&n->buffer, 0, NET_BUFLEN);
 }
 
-int net_sendto(net_t *const n, const char *const buf, const int buf_len) {
-    if (n->fd == -1)
+int net_send(net_t *const n, const char *const buf, const int buf_len) {
+    if (n->fd == -1 || n->raddr.sin_addr.s_addr == 0)
         return -1;
 
     if (sendto(n->fd, buf, buf_len, 0, (struct sockaddr *)&n->raddr, sizeof(n->raddr)) == -1)
@@ -64,11 +61,11 @@ int net_sendto(net_t *const n, const char *const buf, const int buf_len) {
     return 0;
 }
 
-int net_recvfrom(net_t *const n) {
+int net_recv(net_t *const n, void *buf, size_t buf_len) {
     if (n->fd == -1 || n->raddr.sin_addr.s_addr == 0)
         return -1;
 
-    if ((recvfrom(n->fd, n->buffer, NET_BUFLEN, 0, (struct sockaddr *)&n->inaddr, &n->inaddr_len)) == -1)
+    if ((recvfrom(n->fd, buf, buf_len, 0, (struct sockaddr *)&n->inaddr, &n->inaddr_len)) == -1)
         return -1;
 
     if (n->raddr.sin_addr.s_addr != n->inaddr.sin_addr.s_addr) {

src/net.h

@@ -4,21 +4,17 @@
 #include <sys/socket.h>
 #include <netinet/in.h>
 
-#define NET_BUFLEN 256
-
 typedef struct net_t {
     int fd;
     struct sockaddr_in laddr, raddr, inaddr;
     socklen_t raddr_len, inaddr_len;
-
-    char buffer[NET_BUFLEN];
 } net_t;
 
 int net_client_init(net_t *const n, const int af_family, const char *const raddr, const int rport);
 int net_server_init(net_t *const n, const int af_family, const char *const laddr, const int lport);
 void net_destroy(net_t *n);
 
-int net_sendto(net_t *const n, const char *const buf, const int buf_len);
-int net_recvfrom(net_t *const n);
+int net_send(net_t *const n, const char *const buf, const int buf_len);
+int net_recv(net_t *const n, void *buf, size_t buf_len);
 
 #endif /* _NET_H_ */