krun: Set exec args when running nitro variant

The libkrun nitro variant expects the execution arguments to be provided
for forwarding to an enclave. If the nitro variant is configured, set
the execution arguments for the nitro enclave.

Signed-off-by: Tyler Fanelli <tfanelli@redhat.com>

Author: tylerfanelli

src/libcrun/handlers/krun.c

@@ -312,6 +312,8 @@ libkrun_exec (void *cookie, libcrun_container_t *container, const char *pathname
   int32_t (*krun_set_root_disk) (uint32_t ctx_id, const char *disk_path);
   int32_t (*krun_set_tee_config_file) (uint32_t ctx_id, const char *file_path);
   int32_t (*krun_set_console_output) (uint32_t ctx_id, const char *c_filepath);
+  int32_t (*krun_set_exec) (uint32_t ctx_id, const char *exec_path,
+                            const char *const argv[], const char *const envp[]);
   struct krun_config *kconf = (struct krun_config *) cookie;
   void *handle;
   uint32_t num_vcpus, ram_mib;
@@ -375,13 +377,19 @@ libkrun_exec (void *cookie, libcrun_container_t *container, const char *pathname
     {
       // need krun_set_exec and krun_set_console_output.
       krun_set_console_output = dlsym (handle, "krun_set_console_output");
-      if (krun_set_console_output == NULL)
-        error (EXIT_FAILURE, 0, "could not find symbol in `libkrun.so`");
+      krun_set_exec = dlsym (handle, "krun_set_exec");
+      if (krun_set_console_output == NULL || krun_set_exec == NULL)
+        error (EXIT_FAILURE, 0, "could not find symbol in `libkrun-nitro.so`");
 
       // Redirect all enclave output (read from vsock) to stdout.
       ret = krun_set_console_output (ctx_id, "/dev/stdout");
       if (UNLIKELY (ret < 0))
         error (EXIT_FAILURE, -ret, "could not redirect enclave output to stdout");
+
+      ret = krun_set_exec (ctx_id, pathname, (const char *const *) argv,
+                           (const char *const *) def->process->env);
+      if (UNLIKELY (ret < 0))
+        error (EXIT_FAILURE, -ret, "could not set enclave execution arguments");
     }
 
   ret = libkrun_configure_vm (ctx_id, handle, &configured, &config_tree, &err);