diff options
Diffstat (limited to 'contrib/gnome-ssh-askpass3.c')
-rw-r--r-- | contrib/gnome-ssh-askpass3.c | 305 |
1 files changed, 305 insertions, 0 deletions
diff --git a/contrib/gnome-ssh-askpass3.c b/contrib/gnome-ssh-askpass3.c new file mode 100644 index 0000000..e1a0533 --- /dev/null +++ b/contrib/gnome-ssh-askpass3.c @@ -0,0 +1,305 @@ +/* + * Copyright (c) 2000-2002 Damien Miller. All rights reserved. + * + * Redistribution and use in source and binary forms, with or without + * modification, are permitted provided that the following conditions + * are met: + * 1. Redistributions of source code must retain the above copyright + * notice, this list of conditions and the following disclaimer. + * 2. Redistributions in binary form must reproduce the above copyright + * notice, this list of conditions and the following disclaimer in the + * documentation and/or other materials provided with the distribution. + * + * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR + * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES + * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED. + * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT, + * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT + * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE, + * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY + * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT + * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF + * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE. + */ + +/* GTK2 support by Nalin Dahyabhai <nalin@redhat.com> */ + +/* + * This is a simple GNOME SSH passphrase grabber. To use it, set the + * environment variable SSH_ASKPASS to point to the location of + * gnome-ssh-askpass before calling "ssh-add < /dev/null". + * + * There is only two run-time options: if you set the environment variable + * "GNOME_SSH_ASKPASS_GRAB_SERVER=true" then gnome-ssh-askpass will grab + * the X server. If you set "GNOME_SSH_ASKPASS_GRAB_POINTER=true", then the + * pointer will be grabbed too. These may have some benefit to security if + * you don't trust your X server. We grab the keyboard always. + */ + +#define GRAB_TRIES 16 +#define GRAB_WAIT 250 /* milliseconds */ + +#define PROMPT_ENTRY 0 +#define PROMPT_CONFIRM 1 +#define PROMPT_NONE 2 + +/* + * Compile with: + * + * cc -Wall `pkg-config --cflags gtk+-2.0` \ + * gnome-ssh-askpass2.c -o gnome-ssh-askpass \ + * `pkg-config --libs gtk+-2.0` + * + */ + +#include <stdlib.h> +#include <stdio.h> +#include <string.h> +#include <unistd.h> + +#include <X11/Xlib.h> +#include <gtk/gtk.h> +#include <gdk/gdkx.h> +#include <gdk/gdkkeysyms.h> + +static void +ok_dialog(GtkWidget *entry, gpointer dialog) +{ + g_return_if_fail(GTK_IS_DIALOG(dialog)); + gtk_dialog_response(GTK_DIALOG(dialog), GTK_RESPONSE_OK); +} + +static gboolean +check_none(GtkWidget *widget, GdkEventKey *event, gpointer dialog) +{ + switch (event->keyval) { + case GDK_KEY_Escape: + /* esc -> close dialog */ + gtk_dialog_response(GTK_DIALOG(dialog), GTK_RESPONSE_CLOSE); + return TRUE; + case GDK_KEY_Tab: + /* tab -> focus close button */ + gtk_widget_grab_focus(gtk_dialog_get_widget_for_response( + dialog, GTK_RESPONSE_CLOSE)); + return TRUE; + default: + /* eat all other key events */ + return TRUE; + } +} + +static int +parse_env_hex_color(const char *env, GdkColor *c) +{ + const char *s; + unsigned long ul; + char *ep; + size_t n; + + if ((s = getenv(env)) == NULL) + return 0; + + memset(c, 0, sizeof(*c)); + + /* Permit hex rgb or rrggbb optionally prefixed by '#' or '0x' */ + if (*s == '#') + s++; + else if (strncmp(s, "0x", 2) == 0) + s += 2; + n = strlen(s); + if (n != 3 && n != 6) + goto bad; + ul = strtoul(s, &ep, 16); + if (*ep != '\0' || ul > 0xffffff) { + bad: + fprintf(stderr, "Invalid $%s - invalid hex color code\n", env); + return 0; + } + /* Valid hex sequence; expand into a GdkColor */ + if (n == 3) { + /* 4-bit RGB */ + c->red = ((ul >> 8) & 0xf) << 12; + c->green = ((ul >> 4) & 0xf) << 12; + c->blue = (ul & 0xf) << 12; + } else { + /* 8-bit RGB */ + c->red = ((ul >> 16) & 0xff) << 8; + c->green = ((ul >> 8) & 0xff) << 8; + c->blue = (ul & 0xff) << 8; + } + return 1; +} + +static int +passphrase_dialog(char *message, int prompt_type) +{ + const char *failed; + char *passphrase, *local; + int result, grab_tries, grab_server, grab_pointer; + int buttons, default_response; + GtkWidget *parent_window, *dialog, *entry, *err; + GdkGrabStatus status; + GdkColor fg, bg; + GdkSeat *seat; + GdkDisplay *display; + GdkSeatCapabilities caps; + int fg_set = 0, bg_set = 0; + + grab_server = (getenv("GNOME_SSH_ASKPASS_GRAB_SERVER") != NULL); + grab_pointer = (getenv("GNOME_SSH_ASKPASS_GRAB_POINTER") != NULL); + grab_tries = 0; + + fg_set = parse_env_hex_color("GNOME_SSH_ASKPASS_FG_COLOR", &fg); + bg_set = parse_env_hex_color("GNOME_SSH_ASKPASS_BG_COLOR", &bg); + + /* Create an invisible parent window so that GtkDialog doesn't + * complain. */ + parent_window = gtk_window_new(GTK_WINDOW_TOPLEVEL); + + switch (prompt_type) { + case PROMPT_CONFIRM: + buttons = GTK_BUTTONS_YES_NO; + default_response = GTK_RESPONSE_YES; + break; + case PROMPT_NONE: + buttons = GTK_BUTTONS_CLOSE; + default_response = GTK_RESPONSE_CLOSE; + break; + default: + buttons = GTK_BUTTONS_OK_CANCEL; + default_response = GTK_RESPONSE_OK; + break; + } + + dialog = gtk_message_dialog_new(GTK_WINDOW(parent_window), 0, + GTK_MESSAGE_QUESTION, buttons, "%s", message); + + gtk_window_set_title(GTK_WINDOW(dialog), "OpenSSH"); + gtk_window_set_position (GTK_WINDOW(dialog), GTK_WIN_POS_CENTER); + gtk_window_set_keep_above(GTK_WINDOW(dialog), TRUE); + gtk_dialog_set_default_response(GTK_DIALOG(dialog), default_response); + gtk_window_set_keep_above(GTK_WINDOW(dialog), TRUE); + + if (fg_set) + gtk_widget_modify_fg(dialog, GTK_STATE_NORMAL, &fg); + if (bg_set) + gtk_widget_modify_bg(dialog, GTK_STATE_NORMAL, &bg); + + if (prompt_type == PROMPT_ENTRY || prompt_type == PROMPT_NONE) { + entry = gtk_entry_new(); + if (fg_set) + gtk_widget_modify_fg(entry, GTK_STATE_NORMAL, &fg); + if (bg_set) + gtk_widget_modify_bg(entry, GTK_STATE_NORMAL, &bg); + gtk_box_pack_start( + GTK_BOX(gtk_dialog_get_content_area(GTK_DIALOG(dialog))), + entry, FALSE, FALSE, 0); + gtk_entry_set_visibility(GTK_ENTRY(entry), FALSE); + gtk_widget_grab_focus(entry); + if (prompt_type == PROMPT_ENTRY) { + gtk_widget_show(entry); + /* Make <enter> close dialog */ + g_signal_connect(G_OBJECT(entry), "activate", + G_CALLBACK(ok_dialog), dialog); + } else { + /* + * Ensure the 'close' button is not focused by default + * but is still reachable via tab. This is a bit of a + * hack - it uses a hidden entry that responds to a + * couple of keypress events (escape and tab only). + */ + gtk_widget_realize(entry); + g_signal_connect(G_OBJECT(entry), "key_press_event", + G_CALLBACK(check_none), dialog); + } + } + /* Grab focus */ + gtk_widget_show_now(dialog); + display = gtk_widget_get_display(GTK_WIDGET(dialog)); + seat = gdk_display_get_default_seat(display); + caps = GDK_SEAT_CAPABILITY_KEYBOARD; + if (grab_pointer) + caps |= GDK_SEAT_CAPABILITY_ALL_POINTING; + if (grab_server) + caps = GDK_SEAT_CAPABILITY_ALL; + for (;;) { + status = gdk_seat_grab(seat, gtk_widget_get_window(dialog), + caps, TRUE, NULL, NULL, NULL, NULL); + if (status == GDK_GRAB_SUCCESS) + break; + usleep(GRAB_WAIT * 1000); + if (++grab_tries > GRAB_TRIES) + goto nograb; + } + + result = gtk_dialog_run(GTK_DIALOG(dialog)); + + /* Ungrab */ + gdk_seat_ungrab(seat); + gdk_display_flush(display); + + /* Report passphrase if user selected OK */ + if (prompt_type == PROMPT_ENTRY) { + passphrase = g_strdup(gtk_entry_get_text(GTK_ENTRY(entry))); + if (result == GTK_RESPONSE_OK) { + local = g_locale_from_utf8(passphrase, + strlen(passphrase), NULL, NULL, NULL); + if (local != NULL) { + puts(local); + memset(local, '\0', strlen(local)); + g_free(local); + } else { + puts(passphrase); + } + } + /* Zero passphrase in memory */ + memset(passphrase, '\b', strlen(passphrase)); + gtk_entry_set_text(GTK_ENTRY(entry), passphrase); + memset(passphrase, '\0', strlen(passphrase)); + g_free(passphrase); + } + + gtk_widget_destroy(dialog); + if (result != GTK_RESPONSE_OK && result != GTK_RESPONSE_YES) + return -1; + return 0; + + nograb: + gtk_widget_destroy(dialog); + err = gtk_message_dialog_new(GTK_WINDOW(parent_window), 0, + GTK_MESSAGE_ERROR, GTK_BUTTONS_CLOSE, + "Could not grab input. A malicious client may be eavesdropping " + "on your session."); + gtk_window_set_position(GTK_WINDOW(err), GTK_WIN_POS_CENTER); + gtk_dialog_run(GTK_DIALOG(err)); + gtk_widget_destroy(err); + return -1; +} + +int +main(int argc, char **argv) +{ + char *message, *prompt_mode; + int result, prompt_type = PROMPT_ENTRY; + + gtk_init(&argc, &argv); + + if (argc > 1) { + message = g_strjoinv(" ", argv + 1); + } else { + message = g_strdup("Enter your OpenSSH passphrase:"); + } + + if ((prompt_mode = getenv("SSH_ASKPASS_PROMPT")) != NULL) { + if (strcasecmp(prompt_mode, "confirm") == 0) + prompt_type = PROMPT_CONFIRM; + else if (strcasecmp(prompt_mode, "none") == 0) + prompt_type = PROMPT_NONE; + } + + setvbuf(stdout, 0, _IONBF, 0); + result = passphrase_dialog(message, prompt_type); + g_free(message); + + return (result); +} |