Use a new random secret key without keyfile

src/common.c

@@ -68,6 +68,9 @@ static inline int fromhex (const char c)
     if (c>='A' && c<='F')
         return c-'A'+10;
 
+    if (c>='a' && c<='f')
+        return c-'a'+10;
+
     return -1;
 }
 

src/ip-static.h

@@ -12,9 +12,9 @@ static inline int ip_get_version (const uint8_t *data, size_t size)
 }
 
 _pure_
-static inline ssize_t ip_get_size (const uint8_t *data, size_t size)
+static inline ssize_t ip_get_size (const int ip_version, const uint8_t *data, size_t size)
 {
-    switch (ip_get_version(data, size)) {
+    switch (ip_version) {
     case 4:
         return ((data[2]<<8)|data[3]);
     case 6:
@@ -27,9 +27,9 @@ static inline ssize_t ip_get_size (const uint8_t *data, size_t size)
 }
 
 _pure_
-static inline ssize_t ip_get_proto (const uint8_t *data, size_t size)
+static inline ssize_t ip_get_proto (const int ip_version, const uint8_t *data, size_t size)
 {
-    switch (ip_get_version(data, size)) {
+    switch (ip_version) {
     case 4:
         return data[9];
     case 6:
@@ -42,9 +42,9 @@ static inline ssize_t ip_get_proto (const uint8_t *data, size_t size)
 }
 
 _pure_
-static inline ssize_t ip_get_hdr_size (const uint8_t *data, size_t size)
+static inline ssize_t ip_get_hdr_size (const int ip_version, const uint8_t *data, size_t size)
 {
-    switch (ip_get_version(data, size)) {
+    switch (ip_version) {
     case 4:
         return (data[0]&0xF)<<2;
     case 6:

src/main.c

@@ -491,11 +491,10 @@ static int gt_decrypt (struct crypto_ctx *ctx, buffer_t *dst, buffer_t *src)
     return 0;
 }
 
-static void gt_print_hdr (uint8_t *data, size_t ip_size, const char *sockname)
+static void gt_print_hdr (const int ip_version, uint8_t *data, size_t ip_size, const char *sockname)
 {
-    const int ip_version = ip_get_version(data, GT_MTU_MAX);
-    const ssize_t ip_proto = ip_get_proto(data, GT_MTU_MAX);
-    const ssize_t ip_hdr_size = ip_get_hdr_size(data, GT_MTU_MAX);
+    const ssize_t ip_proto = ip_get_proto(ip_version, data, ip_size);
+    const ssize_t ip_hdr_size = ip_get_hdr_size(ip_version, data, ip_size);
 
     char ip_src[33];
     char ip_dst[33];
@@ -555,10 +554,16 @@ static int gt_setup_secretkey (struct crypto_ctx *ctx, char *keyfile)
 {
     const size_t size = sizeof(ctx->skey);
 
-    byte_set(ctx->skey, 1, size);
+    if (!keyfile) {
+        char buf[2*size+1];
+
+        randombytes_buf(ctx->skey, size);
+        gt_tohex(buf, sizeof(buf), ctx->skey, size);
+
+        gt_print("new secret key: %s\n", buf);
 
-    if (!keyfile)
         return 0;
+    }
 
     int fd;
 
@@ -757,11 +762,6 @@ int main (int argc, char **argv)
         return 1;
     }
 
-    struct crypto_ctx ctx;
-
-    if (gt_setup_secretkey(&ctx, keyfile))
-        return 1;
-
     struct addrinfo *ai = ai_create(host, port, listener);
 
     if (!ai)
@@ -800,6 +800,11 @@ int main (int argc, char **argv)
             return 1;
     }
 
+    struct crypto_ctx ctx;
+
+    if (gt_setup_secretkey(&ctx, keyfile))
+        return 1;
+
     if (option_is_set(opts, "daemon")) {
         switch (fork()) {
         case -1:
@@ -943,7 +948,8 @@ int main (int argc, char **argv)
                         break;
                     }
 
-                    const ssize_t ip_size = ip_get_size(data, GT_MTU_MAX);
+                    const int ip_version = ip_get_version(data, GT_MTU_MAX);
+                    const ssize_t ip_size = ip_get_size(ip_version, data, GT_MTU_MAX);
 
                     if _0_(ip_size<=0)
                         continue;
@@ -956,7 +962,7 @@ int main (int argc, char **argv)
                     }
 
                     if _0_(debug)
-                        gt_print_hdr(data, ip_size, sockname);
+                        gt_print_hdr(ip_version, data, ip_size, sockname);
 
                     blks[blk_write++].size = r;
                     blk_count++;
@@ -1031,7 +1037,9 @@ int main (int argc, char **argv)
                 }
 
                 size_t size = buffer_read_size(&tun.write);
-                ssize_t ip_size = ip_get_size(tun.write.read, size);
+
+                const int ip_version = ip_get_version(tun.write.read, size);
+                ssize_t ip_size = ip_get_size(ip_version, tun.write.read, size);
 
                 if _0_(!ip_size) {
                     gt_log("%s: bad packet!\n", sockname);