mobilebackup2: Finish mobilebackup2_version_exchange() and use it in idevicebackup2

3 files changed, 26 insertions, 17 deletions

diff --git a/include/libimobiledevice/mobilebackup2.h b/include/libimobiledevice/mobilebackup2.h
index a58dc00..5d695e9 100644
--- a/include/libimobiledevice/mobilebackup2.h
+++ b/include/libimobiledevice/mobilebackup2.h
@@ -37,6 +37,7 @@ extern "C" {
 #define MOBILEBACKUP2_E_MUX_ERROR             -3
 #define MOBILEBACKUP2_E_BAD_VERSION           -4
 #define MOBILEBACKUP2_E_REPLY_NOT_OK          -5
+#define MOBILEBACKUP2_E_NO_COMMON_VERSION     -6
 
 #define MOBILEBACKUP2_E_UNKNOWN_ERROR       -256
 /*@}*/
@@ -52,7 +53,7 @@ mobilebackup2_error_t mobilebackup2_client_free(mobilebackup2_client_t client);
 mobilebackup2_error_t mobilebackup2_receive_message(mobilebackup2_client_t client, plist_t *msg_plist, char **dlmessage);
 mobilebackup2_error_t mobilebackup2_send_raw(mobilebackup2_client_t client, const char *data, uint32_t length, uint32_t *bytes);
 mobilebackup2_error_t mobilebackup2_receive_raw(mobilebackup2_client_t client, char *data, uint32_t length, uint32_t *bytes);
-mobilebackup2_error_t mobilebackup2_version_exchange(mobilebackup2_client_t client);
+mobilebackup2_error_t mobilebackup2_version_exchange(mobilebackup2_client_t client, double local_versions[], char count, double *remote_version);
 mobilebackup2_error_t mobilebackup2_send_request(mobilebackup2_client_t client, const char *request, const char *target_identifier, const char *source_identifier, plist_t options);
 mobilebackup2_error_t mobilebackup2_send_status_response(mobilebackup2_client_t client, int status_code, const char *status1, plist_t status2);
 
diff --git a/src/mobilebackup2.c b/src/mobilebackup2.c
index ae7ac03..a595b01 100644
--- a/src/mobilebackup2.c
+++ b/src/mobilebackup2.c
@@ -346,20 +346,26 @@ mobilebackup2_error_t mobilebackup2_receive_raw(mobilebackup2_client_t client, c
 /**
  * Performs the mobilebackup2 protocol version exchange.
  * 
- * @param The MobileBackup client to use.
+ * @param client The MobileBackup client to use.
+ * @param local_versions An array of supported versions to send to the remote.
+ * @param count The number of items in local_versions.
+ * @param remote_version Holds the protocol version of the remote on success.
  * 
  * @return MOBILEBACKUP2_E_SUCCESS on success, or a MOBILEBACKUP2_E_* error
  *     code otherwise.
  */
-mobilebackup2_error_t mobilebackup2_version_exchange(mobilebackup2_client_t client)
+mobilebackup2_error_t mobilebackup2_version_exchange(mobilebackup2_client_t client, double local_versions[], char count, double *remote_version)
 {
+        int i;
+
         if (!client || !client->parent)
                 return MOBILEBACKUP2_E_INVALID_ARG;
 
         plist_t dict = plist_new_dict();
         plist_t array = plist_new_array();
-        plist_array_append_item(array, plist_new_real(2.0));
-        plist_array_append_item(array, plist_new_real(2.1));
+        for (i = 0; i < count; i++) {
+                plist_array_append_item(array, plist_new_real(local_versions[i]));
+        }
         plist_dict_insert_item(dict, "SupportedProtocolVersions", array);
 
         mobilebackup2_error_t err = internal_mobilebackup2_send_message(client, "Hello", dict);
@@ -373,6 +379,7 @@ mobilebackup2_error_t mobilebackup2_version_exchange(mobilebackup2_client_t clie
         if (err != MOBILEBACKUP2_E_SUCCESS)
                 goto leave;
 
+        /* check if we received an error */
         plist_t node = plist_dict_get_item(dict, "ErrorCode");
         if (!node || (plist_get_node_type(node) != PLIST_UINT)) {
                 err = MOBILEBACKUP2_E_PLIST_ERROR;
@@ -381,27 +388,24 @@ mobilebackup2_error_t mobilebackup2_version_exchange(mobilebackup2_client_t clie
 
         uint64_t val = 0;
         plist_get_uint_val(node, &val);
-
         if (val != 0) {
-                err = MOBILEBACKUP2_E_REPLY_NOT_OK;
+                if (val == 1) {
+                        err = MOBILEBACKUP2_E_NO_COMMON_VERSION;
+                } else {
+                        err = MOBILEBACKUP2_E_REPLY_NOT_OK;
+                }
                 goto leave;
         }
 
+        /* retrieve the protocol version of the device */
         node = plist_dict_get_item(dict, "ProtocolVersion");
         if (!node || (plist_get_node_type(node) != PLIST_REAL)) {
                 err = MOBILEBACKUP2_E_PLIST_ERROR;
                 goto leave;
         }
 
-        double rval = 0.0;
-        plist_get_real_val(node, &rval);
-
-        debug_info("using protocol version %f\n", rval);
-
-        // TODO version check ??
-        // if version does not match
-        //      err = MOBILEBACKUP2_E_BAD_VERSION
-
+        *remote_version = 0.0;
+        plist_get_real_val(node, remote_version);
 leave:
         if (dict)
                 plist_free(dict);
diff --git a/tools/idevicebackup2.c b/tools/idevicebackup2.c
index b9187e9..113180b 100644
--- a/tools/idevicebackup2.c
+++ b/tools/idevicebackup2.c
@@ -1231,13 +1231,17 @@ int main(int argc, char *argv[])
                 mobilebackup2_client_new(phone, port, &mobilebackup2);
 
                 /* send Hello message */
-                err = mobilebackup2_version_exchange(mobilebackup2);
+                double local_versions[2] = {2.0, 2.1};
+                double remote_version = 0.0;
+                err = mobilebackup2_version_exchange(mobilebackup2, local_versions, 2, &remote_version);
                 if (err != MOBILEBACKUP2_E_SUCCESS) {
                         printf("Could not perform backup protocol version exchange, error code %d\n", err);
                         cmd = CMD_LEAVE;
                         goto checkpoint;
                 }
 
+                PRINT_VERBOSE(1, "Negotiated Protocol Version %.1f\n", remote_version);
+
                 /* check abort conditions */
                 if (quit_flag > 0) {
                         PRINT_VERBOSE(1, "Aborting as requested by user...\n");