lockdown: Don't explicitly validate pairing unless we're dealing with an older device

On newer iOS version, ValidatePair is not mandatory to gain trusted host
status. Starting with iOS 11, the ValidatePair request has been removed from
lockdownd and will throw an error. This commit adds a version check so that
ValidatePair is only called on devices prior iOS 7.

3 files changed, 27 insertions, 12 deletions

diff --git a/src/idevice.c b/src/idevice.c
index 21b10ba..ead9b86 100644
--- a/src/idevice.c
+++ b/src/idevice.c
@@ -256,6 +256,7 @@ LIBIMOBILEDEVICE_API idevice_error_t idevice_new(idevice_t * device, const char
                 dev->udid = strdup(muxdev.udid);
                 dev->conn_type = CONNECTION_USBMUXD;
                 dev->conn_data = (void*)(long)muxdev.handle;
+                dev->version = 0;
                 *device = dev;
                 return IDEVICE_E_SUCCESS;
         }
diff --git a/src/idevice.h b/src/idevice.h
index 1354cc0..e46a7e5 100644
--- a/src/idevice.h
+++ b/src/idevice.h
@@ -76,6 +76,7 @@ struct idevice_private {
         char *udid;
         enum connection_type conn_type;
         void *conn_data;
+        int version;
 };
 
 #endif
diff --git a/src/lockdown.c b/src/lockdown.c
index 5251737..071697d 100644
--- a/src/lockdown.c
+++ b/src/lockdown.c
@@ -707,6 +707,19 @@ LIBIMOBILEDEVICE_API lockdownd_error_t lockdownd_client_new_with_handshake(idevi
         }
         free(type);
 
+        if (device->version == 0) {
+                plist_t p_version = NULL;
+                if (lockdownd_get_value(client_loc, NULL, "ProductVersion", &p_version) == LOCKDOWN_E_SUCCESS) {
+                        int vers[3] = {0, 0, 0};
+                        char *s_version = NULL;
+                        plist_get_string_val(p_version, &s_version);
+                        if (s_version && sscanf(s_version, "%d.%d.%d", &vers[0], &vers[1], &vers[2]) >= 2) {
+                                device->version = ((vers[0] & 0xFF) << 16) | ((vers[1] & 0xFF) << 8) | (vers[2] & 0xFF);
+                        }
+                        free(s_version);
+                }
+        }
+
         userpref_read_pair_record(client_loc->udid, &pair_record);
         if (pair_record) {
                 pair_record_get_host_id(pair_record, &host_id);
@@ -723,18 +736,18 @@ LIBIMOBILEDEVICE_API lockdownd_error_t lockdownd_client_new_with_handshake(idevi
         plist_free(pair_record);
         pair_record = NULL;
 
-        /* in any case, we need to validate pairing to receive trusted host status */
-        ret = lockdownd_validate_pair(client_loc, NULL);
-
-        /* if not paired yet, let's do it now */
-        if (LOCKDOWN_E_INVALID_HOST_ID == ret) {
-                free(host_id);
-                host_id = NULL;
-                ret = lockdownd_pair(client_loc, NULL);
-                if (LOCKDOWN_E_SUCCESS == ret) {
-                        ret = lockdownd_validate_pair(client_loc, NULL);
-                } else if (LOCKDOWN_E_PAIRING_DIALOG_RESPONSE_PENDING == ret) {
-                        debug_info("Device shows the pairing dialog.");
+        if (device->version < 0x070000) {
+                /* for older devices, we need to validate pairing to receive trusted host status */
+                ret = lockdownd_validate_pair(client_loc, NULL);
+
+                /* if not paired yet, let's do it now */
+                if (LOCKDOWN_E_INVALID_HOST_ID == ret) {
+                        free(host_id);
+                        host_id = NULL;
+                        ret = lockdownd_pair(client_loc, NULL);
+                        if (LOCKDOWN_E_SUCCESS == ret) {
+                                ret = lockdownd_validate_pair(client_loc, NULL);
+                        }
                 }
         }