diff options
Diffstat (limited to 'src/libnm-core-impl/nm-utils.c')
| -rw-r--r-- | src/libnm-core-impl/nm-utils.c | 255 |
1 files changed, 255 insertions, 0 deletions
diff --git a/src/libnm-core-impl/nm-utils.c b/src/libnm-core-impl/nm-utils.c index 6d5df98c..9a78e947 100644 --- a/src/libnm-core-impl/nm-utils.c +++ b/src/libnm-core-impl/nm-utils.c @@ -17,6 +17,7 @@ #include <linux/pkt_sched.h> #include <linux/if_infiniband.h> +#include "libnm-glib-aux/nm-io-utils.h" #include "libnm-glib-aux/nm-uuid.h" #include "libnm-glib-aux/nm-json-aux.h" #include "libnm-glib-aux/nm-str-buf.h" @@ -6195,3 +6196,257 @@ nm_utils_ensure_gtypes(void) for (meta_type = 0; meta_type < _NM_META_SETTING_TYPE_NUM; meta_type++) nm_meta_setting_infos[meta_type].get_setting_gtype(); } + +/*****************************************************************************/ + +typedef struct { + GPid pid; + GSource *child_watch_source; + GMainLoop *loop; + GError *error; + + int child_stdout; + int child_stderr; + + GSource *output_source; + GSource *error_source; + + NMStrBuf output_buffer; + NMStrBuf error_buffer; +} HelperInfo; + +static void +helper_complete(HelperInfo *info, GError *error_take) +{ + if (error_take) { + if (!info->error) + info->error = error_take; + else + g_error_free(error_take); + } + + if (info->output_source || info->error_source || info->pid != -1) { + /* Wait that the pipe is closed and process has terminated */ + return; + } + + if (info->error && info->error_buffer.len > 0) { + /* Prefer the message from stderr as it's more informative */ + g_error_free(info->error); + info->error = g_error_new(NM_CONNECTION_ERROR, + NM_CONNECTION_ERROR_FAILED, + "%s", + nm_str_buf_get_str(&info->error_buffer)); + } + + g_main_loop_quit(info->loop); +} + +static gboolean +helper_have_err_data(int fd, GIOCondition condition, gpointer user_data) +{ + HelperInfo *info = user_data; + gssize n_read; + GError *error = NULL; + + n_read = nm_utils_fd_read(fd, &info->error_buffer); + + if (n_read > 0) + return G_SOURCE_CONTINUE; + + nm_clear_g_source_inst(&info->error_source); + nm_clear_fd(&info->child_stderr); + + if (n_read < 0) { + error = g_error_new(NM_UTILS_ERROR, + NM_UTILS_ERROR_UNKNOWN, + "read from process returned %d (%s)", + (int) -n_read, + nm_strerror_native((int) -n_read)); + } + + helper_complete(info, error); + return G_SOURCE_CONTINUE; +} + +static gboolean +helper_have_data(int fd, GIOCondition condition, gpointer user_data) +{ + HelperInfo *info = user_data; + gssize n_read; + GError *error = NULL; + + n_read = nm_utils_fd_read(fd, &info->output_buffer); + + if (n_read > 0) + return G_SOURCE_CONTINUE; + + nm_clear_g_source_inst(&info->output_source); + nm_clear_fd(&info->child_stdout); + + if (n_read < 0) { + error = g_error_new(NM_UTILS_ERROR, + NM_UTILS_ERROR_UNKNOWN, + "read from process returned %d (%s)", + (int) -n_read, + nm_strerror_native((int) -n_read)); + } + + helper_complete(info, error); + return G_SOURCE_CONTINUE; +} + +static void +helper_child_terminated(GPid pid, int status, gpointer user_data) +{ + HelperInfo *info = user_data; + gs_free char *status_desc = NULL; + GError *error = NULL; + + info->pid = -1; + nm_clear_g_source_inst(&info->child_watch_source); + + if (!WIFEXITED(status) || WEXITSTATUS(status) != 0) { + if (!status_desc) + status_desc = nm_utils_get_process_exit_status_desc(status); + error = + g_error_new(NM_UTILS_ERROR, NM_UTILS_ERROR_UNKNOWN, "helper process %s", status_desc); + } + + helper_complete(info, error); +} + +#define RUN_CERT_DIR NMRUNDIR "/cert" + +/** + * nm_utils_copy_cert_as_user: + * @filename: the file name of the certificate or key to copy + * @user: the user to impersonate when reading the file + * @error: (nullable): return location for a #GError, or %NULL + * + * Reads @filename on behalf of user @user and writes the + * content to a new file in /run/NetworkManager/cert/. + * The new file has permission 600 and is owned by root. + * + * This function is useful for VPN plugins that run as root and need + * to verify that the user owning the connection (the one listed in the + * connection.permissions property) can access the file. + * + * Returns: (transfer full): the name of the new temporary file. Or %NULL + * if an error occurred, including when the given user can't access the + * file. + * + * Since: 1.56, 1.54.3 + */ +char * +nm_utils_copy_cert_as_user(const char *filename, const char *user, GError **error) +{ + gs_unref_bytes GBytes *bytes = NULL; + char dst_path[] = RUN_CERT_DIR "/XXXXXX"; + HelperInfo info = { + .child_stdout = -1, + .child_stderr = -1, + }; + GMainContext *context; + int fd = -1; + + g_return_val_if_fail(filename, NULL); + g_return_val_if_fail(user, NULL); + g_return_val_if_fail(!error || !*error, NULL); + + if (geteuid() != 0) { + g_set_error_literal(error, + NM_CONNECTION_ERROR, + NM_CONNECTION_ERROR_INVALID_PROPERTY, + _("This function needs to be called by root")); + return NULL; + } + + if (!g_spawn_async_with_pipes( + "/", + (char **) + NM_MAKE_STRV(LIBEXECDIR "/nm-libnm-helper", "read-file-as-user", filename, user), + (char **) NM_MAKE_STRV(), + G_SPAWN_CLOEXEC_PIPES | G_SPAWN_DO_NOT_REAP_CHILD, + NULL, + NULL, + &info.pid, + NULL, + &info.child_stdout, + &info.child_stderr, + error)) { + return NULL; + } + + context = g_main_context_new(); + info.loop = g_main_loop_new(context, FALSE); + + /* Watch process */ + info.child_watch_source = nm_g_child_watch_source_new(info.pid, + G_PRIORITY_DEFAULT, + helper_child_terminated, + &info, + NULL); + g_source_attach(info.child_watch_source, context); + + /* Watch stdout */ + info.output_buffer = NM_STR_BUF_INIT(0, FALSE); + info.output_source = nm_g_unix_fd_source_new(info.child_stdout, + G_IO_IN | G_IO_ERR | G_IO_HUP, + G_PRIORITY_DEFAULT, + helper_have_data, + &info, + NULL); + g_source_attach(info.output_source, context); + + /* Watch stderr */ + info.error_buffer = NM_STR_BUF_INIT(0, FALSE); + info.error_source = nm_g_unix_fd_source_new(info.child_stderr, + G_IO_IN | G_IO_ERR | G_IO_HUP, + G_PRIORITY_DEFAULT, + helper_have_err_data, + &info, + NULL); + g_source_attach(info.error_source, context); + + /* Wait termination */ + g_main_loop_run(info.loop); + g_clear_pointer(&info.loop, g_main_loop_unref); + g_clear_pointer(&context, g_main_context_unref); + + if (info.error) { + nm_str_buf_destroy(&info.output_buffer); + nm_str_buf_destroy(&info.error_buffer); + g_propagate_error(error, g_steal_pointer(&info.error)); + return NULL; + } + + /* Write the data to a new file */ + + bytes = g_bytes_new(nm_str_buf_get_str_unsafe(&info.output_buffer), info.output_buffer.len); + nm_str_buf_destroy(&info.output_buffer); + nm_str_buf_destroy(&info.error_buffer); + + mkdir(RUN_CERT_DIR, 0600); + fd = mkstemp(dst_path); + if (fd < 0) { + g_set_error_literal(error, + NM_CONNECTION_ERROR, + NM_CONNECTION_ERROR_INVALID_PROPERTY, + _("Failure creating the temporary file")); + return NULL; + } + nm_close(fd); + + if (!nm_utils_file_set_contents(dst_path, + g_bytes_get_data(bytes, NULL), + g_bytes_get_size(bytes), + 0600, + NULL, + NULL, + error)) { + return NULL; + } + + return g_strdup(dst_path); +} |