Move SSL code into iphone.c/iphone.h

1 files changed, 257 insertions, 17 deletions

diff --git a/src/iphone.c b/src/iphone.c
index ce90299..8bc9e8d 100644
--- a/src/iphone.c
+++ b/src/iphone.c
@@ -26,6 +26,7 @@
 #include <arpa/inet.h>
 
 #include <usbmuxd.h>
+#include <gnutls/gnutls.h>
 #include "iphone.h"
 #include "debug.h"
 
@@ -222,6 +223,7 @@ iphone_error_t iphone_device_connect(iphone_device_t device, uint16_t dst_port,
                 iphone_connection_t new_connection = (iphone_connection_t)malloc(sizeof(struct iphone_connection_int));
                 new_connection->type = CONNECTION_USBMUXD;
                 new_connection->data = (void*)sfd;
+                new_connection->ssl_data = NULL;
                 *connection = new_connection;
                 return IPHONE_E_SUCCESS;
         } else {
@@ -243,6 +245,10 @@ iphone_error_t iphone_device_disconnect(iphone_connection_t connection)
         if (!connection) {
                 return IPHONE_E_INVALID_ARG;
         }
+        /* shut down ssl if enabled */
+        if (connection->ssl_data) {
+                iphone_connection_disable_ssl(connection);
+        }
         iphone_error_t result = IPHONE_E_UNKNOWN_ERROR;
         if (connection->type == CONNECTION_USBMUXD) {
                 usbmuxd_disconnect((int)(connection->data));
@@ -255,6 +261,29 @@ iphone_error_t iphone_device_disconnect(iphone_connection_t connection)
 }
 
 /**
+ * Internally used function to send raw data over the given connection.
+ */
+static iphone_error_t internal_connection_send(iphone_connection_t connection, const char *data, uint32_t len, uint32_t *sent_bytes)
+{
+        if (!connection || !data) {
+                return IPHONE_E_INVALID_ARG;
+        }
+
+        if (connection->type == CONNECTION_USBMUXD) {
+                int res = usbmuxd_send((int)(connection->data), data, len, sent_bytes);
+                if (res < 0) {
+                        debug_info("ERROR: usbmuxd_send returned %d (%s)", res, strerror(-res));
+                        return IPHONE_E_UNKNOWN_ERROR;
+                }
+                return IPHONE_E_SUCCESS;
+        } else {
+                debug_info("Unknown connection type %d", connection->type);
+        }
+        return IPHONE_E_UNKNOWN_ERROR;
+
+}
+
+/**
  * Send data to a device via the given connection.
  *
  * @param connection The connection to send data over.
@@ -267,14 +296,36 @@ iphone_error_t iphone_device_disconnect(iphone_connection_t connection)
  */
 iphone_error_t iphone_device_send(iphone_connection_t connection, const char *data, uint32_t len, uint32_t *sent_bytes)
 {
-        if (!connection || !data) {
+        if (!connection || !data || (connection->ssl_data && !connection->ssl_data->session)) {
+                return IPHONE_E_INVALID_ARG;
+        }
+
+        if (connection->ssl_data) {
+                ssize_t sent = gnutls_record_send(connection->ssl_data->session, (void*)data, (size_t)len);
+                if ((uint32_t)sent == (uint32_t)len) {
+                        *sent_bytes = sent;
+                        return IPHONE_E_SUCCESS;
+                }
+                *sent_bytes = 0;
+                return IPHONE_E_SSL_ERROR;
+        }
+        return internal_connection_send(connection, data, len, sent_bytes);
+}
+
+/**
+ * Internally used function for receiving raw data over the given connection
+ * using a timeout.
+ */
+static iphone_error_t internal_connection_recv_timeout(iphone_connection_t connection, char *data, uint32_t len, uint32_t *recv_bytes, unsigned int timeout)
+{
+        if (!connection) {
                 return IPHONE_E_INVALID_ARG;
         }
 
         if (connection->type == CONNECTION_USBMUXD) {
-                int res = usbmuxd_send((int)(connection->data), data, len, sent_bytes);
+                int res = usbmuxd_recv_timeout((int)(connection->data), data, len, recv_bytes, timeout);
                 if (res < 0) {
-                        debug_info("ERROR: usbmuxd_send returned %d (%s)", res, strerror(-res));
+                        debug_info("ERROR: usbmuxd_recv_timeout returned %d (%s)", res, strerror(-res));
                         return IPHONE_E_UNKNOWN_ERROR;
                 }
                 return IPHONE_E_SUCCESS;
@@ -301,16 +352,38 @@ iphone_error_t iphone_device_send(iphone_connection_t connection, const char *da
  */
 iphone_error_t iphone_device_recv_timeout(iphone_connection_t connection, char *data, uint32_t len, uint32_t *recv_bytes, unsigned int timeout)
 {
+        if (!connection || (connection->ssl_data && !connection->ssl_data->session)) {
+                return IPHONE_E_INVALID_ARG;
+        }
+
+        if (connection->ssl_data) {
+                ssize_t received = gnutls_record_recv(connection->ssl_data->session, (void*)data, (size_t)len);
+                if (received > 0) {
+                        *recv_bytes = received;
+                        return IPHONE_E_SUCCESS;
+                }
+                *recv_bytes = 0;
+                return IPHONE_E_SSL_ERROR;
+        }
+        return internal_connection_recv_timeout(connection, data, len, recv_bytes, timeout);
+}
+
+/**
+ * Internally used function for receiving raw data over the given connection.
+ */
+static iphone_error_t internal_connection_recv(iphone_connection_t connection, char *data, uint32_t len, uint32_t *recv_bytes)
+{
         if (!connection) {
                 return IPHONE_E_INVALID_ARG;
         }
 
         if (connection->type == CONNECTION_USBMUXD) {
-                int res = usbmuxd_recv_timeout((int)(connection->data), data, len, recv_bytes, timeout);
+                int res = usbmuxd_recv((int)(connection->data), data, len, recv_bytes);
                 if (res < 0) {
-                        debug_info("ERROR: usbmuxd_recv_timeout returned %d (%s)", res, strerror(-res));
+                        debug_info("ERROR: usbmuxd_recv returned %d (%s)", res, strerror(-res));
                         return IPHONE_E_UNKNOWN_ERROR;
                 }
+
                 return IPHONE_E_SUCCESS;
         } else {
                 debug_info("Unknown connection type %d", connection->type);
@@ -333,22 +406,20 @@ iphone_error_t iphone_device_recv_timeout(iphone_connection_t connection, char *
  */
 iphone_error_t iphone_device_recv(iphone_connection_t connection, char *data, uint32_t len, uint32_t *recv_bytes)
 {
-        if (!connection) {
-                return -EINVAL;
+        if (!connection || (connection->ssl_data && !connection->ssl_data->session)) {
+                return IPHONE_E_INVALID_ARG;
         }
 
-        if (connection->type == CONNECTION_USBMUXD) {
-                int res = usbmuxd_recv((int)(connection->data), data, len, recv_bytes);
-                if (res < 0) {
-                        debug_info("ERROR: usbmuxd_recv returned %d (%s)", res, strerror(-res));
-                        return IPHONE_E_UNKNOWN_ERROR;
+        if (connection->ssl_data) {
+                ssize_t received = gnutls_record_recv(connection->ssl_data->session, (void*)data, (size_t)len);
+                if (received > 0) {
+                        *recv_bytes = received;
+                        return IPHONE_E_SUCCESS;
                 }
-
-                return IPHONE_E_SUCCESS;
-        } else {
-                debug_info("Unknown connection type %d", connection->type);
+                *recv_bytes = 0;
+                return IPHONE_E_SSL_ERROR;
         }
-        return IPHONE_E_UNKNOWN_ERROR;
+        return internal_connection_recv(connection, data, len, recv_bytes);
 }
 
 iphone_error_t iphone_device_get_handle(iphone_device_t device, uint32_t *handle)
@@ -374,3 +445,172 @@ iphone_error_t iphone_device_get_uuid(iphone_device_t device, char **uuid)
         return IPHONE_E_SUCCESS;
 }
 
+/**
+ * Internally used gnutls callback function for receiving encrypted data.
+ */
+static ssize_t internal_ssl_read(gnutls_transport_ptr_t transport, char *buffer, size_t length)
+{
+        int bytes = 0, pos_start_fill = 0;
+        size_t tbytes = 0;
+        int this_len = length;
+        iphone_error_t res;
+        iphone_connection_t connection = (iphone_connection_t)transport;
+        char *recv_buffer;
+
+        debug_info("pre-read client wants %zi bytes", length);
+
+        recv_buffer = (char *) malloc(sizeof(char) * this_len);
+
+        /* repeat until we have the full data or an error occurs */
+        do {
+                if ((res = internal_connection_recv(connection, recv_buffer, this_len, (uint32_t*)&bytes)) != IPHONE_E_SUCCESS) {
+                        debug_info("ERROR: iphone_device_recv returned %d", res);
+                        return res;
+                }
+                debug_info("post-read we got %i bytes", bytes);
+
+                // increase read count
+                tbytes += bytes;
+
+                // fill the buffer with what we got right now
+                memcpy(buffer + pos_start_fill, recv_buffer, bytes);
+                pos_start_fill += bytes;
+
+                if (tbytes >= length) {
+                        break;
+                }
+
+                this_len = length - tbytes;
+                debug_info("re-read trying to read missing %i bytes", this_len);
+        } while (tbytes < length);
+
+        if (recv_buffer) {
+                free(recv_buffer);
+        }
+        return tbytes;
+}
+
+/**
+ * Internally used gnutls callback function for sending encrypted data.
+ */
+static ssize_t internal_ssl_write(gnutls_transport_ptr_t transport, char *buffer, size_t length)
+{
+        uint32_t bytes = 0;
+        iphone_connection_t connection = (iphone_connection_t)transport;
+        debug_info("pre-send length = %zi", length);
+        internal_connection_send(connection, buffer, length, &bytes);
+        debug_info("post-send sent %i bytes", bytes);
+        return bytes;
+}
+
+/**
+ * Internally used function for cleaning up SSL stuff.
+ */
+static void internal_ssl_cleanup(ssl_data_t ssl_data)
+{
+        if (!ssl_data)
+                return;
+
+        if (ssl_data->session) {
+                gnutls_deinit(ssl_data->session);
+        }
+        if (ssl_data->certificate) {
+                gnutls_certificate_free_credentials(ssl_data->certificate);
+        }
+}
+
+/**
+ * Enables SSL for the given connection.
+ *
+ * @param connection The connection to enable SSL for.
+ *
+ * @return IPHONE_E_SUCCESS on success, IPHONE_E_INVALID_ARG when connection
+ *     is NULL or connection->ssl_data is non-NULL, or IPHONE_E_SSL_ERROR when
+ *     SSL initialization, setup, or handshake fails.
+ */
+iphone_error_t iphone_connection_enable_ssl(iphone_connection_t connection)
+{
+        if (!connection || connection->ssl_data)
+                return IPHONE_E_INVALID_ARG;
+
+        iphone_error_t ret = IPHONE_E_SSL_ERROR;
+        uint32_t return_me = 0;
+
+        ssl_data_t ssl_data_loc = (ssl_data_t)malloc(sizeof(struct ssl_data_int));
+
+        // Set up GnuTLS...
+        debug_info("enabling SSL mode");
+        errno = 0;
+        gnutls_global_init();
+        gnutls_certificate_allocate_credentials(&ssl_data_loc->certificate);
+        gnutls_certificate_set_x509_trust_file(ssl_data_loc->certificate, "hostcert.pem", GNUTLS_X509_FMT_PEM);
+        gnutls_init(&ssl_data_loc->session, GNUTLS_CLIENT);
+        {
+                int protocol_priority[16] = { GNUTLS_SSL3, 0 };
+                int kx_priority[16] = { GNUTLS_KX_ANON_DH, GNUTLS_KX_RSA, 0 };
+                int cipher_priority[16] = { GNUTLS_CIPHER_AES_128_CBC, GNUTLS_CIPHER_AES_256_CBC, 0 };
+                int mac_priority[16] = { GNUTLS_MAC_SHA1, GNUTLS_MAC_MD5, 0 };
+                int comp_priority[16] = { GNUTLS_COMP_NULL, 0 };
+
+                gnutls_cipher_set_priority(ssl_data_loc->session, cipher_priority);
+                gnutls_compression_set_priority(ssl_data_loc->session, comp_priority);
+                gnutls_kx_set_priority(ssl_data_loc->session, kx_priority);
+                gnutls_protocol_set_priority(ssl_data_loc->session, protocol_priority);
+                gnutls_mac_set_priority(ssl_data_loc->session, mac_priority);
+        }
+        gnutls_credentials_set(ssl_data_loc->session, GNUTLS_CRD_CERTIFICATE, ssl_data_loc->certificate); // this part is killing me.
+
+        debug_info("GnuTLS step 1...");
+        gnutls_transport_set_ptr(ssl_data_loc->session, (gnutls_transport_ptr_t)connection);
+        debug_info("GnuTLS step 2...");
+        gnutls_transport_set_push_function(ssl_data_loc->session, (gnutls_push_func) & internal_ssl_write);
+        debug_info("GnuTLS step 3...");
+        gnutls_transport_set_pull_function(ssl_data_loc->session, (gnutls_pull_func) & internal_ssl_read);
+        debug_info("GnuTLS step 4 -- now handshaking...");
+        if (errno)
+                debug_info("WARN: errno says %s before handshake!", strerror(errno));
+        return_me = gnutls_handshake(ssl_data_loc->session);
+        debug_info("GnuTLS handshake done...");
+
+        if (return_me != GNUTLS_E_SUCCESS) {
+                internal_ssl_cleanup(ssl_data_loc);
+                free(ssl_data_loc);
+                debug_info("GnuTLS reported something wrong.");
+                gnutls_perror(return_me);
+                debug_info("oh.. errno says %s", strerror(errno));
+        } else {
+                connection->ssl_data = ssl_data_loc;
+                ret = IPHONE_E_SUCCESS;
+                debug_info("SSL mode enabled");
+        }
+        return ret;
+}
+
+/**
+ * Disable SSL for the given connection.
+ *
+ * @param connection The connection to disable SSL for.
+ *
+ * @return IPHONE_E_SUCCESS on success, IPHONE_E_INVALID_ARG when connection
+ *     is NULL. This function also returns IPHONE_E_SUCCESS when SSL is not
+ *     enabled and does no further error checking on cleanup.
+ */
+iphone_error_t iphone_connection_disable_ssl(iphone_connection_t connection)
+{
+        if (!connection)
+                return IPHONE_E_INVALID_ARG;
+        if (!connection->ssl_data) {
+                /* ignore if ssl is not enabled */ 
+                return IPHONE_E_SUCCESS;
+        }
+
+        if (connection->ssl_data->session) {
+                gnutls_bye(connection->ssl_data->session, GNUTLS_SHUT_RDWR);
+        }
+        internal_ssl_cleanup(connection->ssl_data);
+        free(connection->ssl_data);
+        connection->ssl_data = NULL;
+
+        return IPHONE_E_SUCCESS;
+}
+