hook/pro: Add net-crypt module, monitor network packet decryption failure

cmake/src/main/hook/pri/CMakeLists.txt

@@ -8,6 +8,7 @@ add_resources(DOG_KEY ${SRC} prihook.hasp.key)
 
 set(SOURCE_FILES
         ${SRC}/main.c
+        ${SRC}/net-crypt.c
         ${SRC}/options.c
         ${SRC}/usb-updates.c)
 

src/main/hook/pri/net-crypt.c

@@ -0,0 +1,40 @@
+#define LOG_MODULE "prinet-net-crypt"
+
+#include "capnhook/hook/lib.h"
+
+#include "util/log.h"
+
+typedef int (*crypto_box_open_easy_t)(
+        unsigned char* m,
+        const unsigned char* c,
+        unsigned long long clen,
+        unsigned long long unkn_len,
+        const unsigned char* n,
+        const unsigned char* pk,
+        const unsigned char* sk);
+
+static crypto_box_open_easy_t prihook_net_crypt_real_crypto_box_open_easy;
+
+int crypto_box_open_easy(
+        unsigned char* m,
+        const unsigned char* c,
+        unsigned long long clen,
+        unsigned long long unkn_len,
+        const unsigned char* n,
+        const unsigned char* pk,
+        const unsigned char* sk)
+{
+    if (!prihook_net_crypt_real_crypto_box_open_easy) {
+        prihook_net_crypt_real_crypto_box_open_easy =
+            (crypto_box_open_easy_t) cnh_lib_get_func_addr("crypto_box_open_easy");
+    }
+
+    int res = prihook_net_crypt_real_crypto_box_open_easy(
+        m, c, clen, unkn_len, n, pk, sk);
+
+    if (res != 0) {
+        log_error("Decrypting message (len %d) failed: %d", clen, res);
+    }
+
+    return res;
+}