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mirror of https://git.tartarus.org/simon/putty.git synced 2025-01-10 01:48:00 +00:00
putty-source/unix/platform.h
Simon Tatham f1c8298000 Centralise most details of host-key prompting.
The text of the host key warnings was replicated in three places: the
Windows rc file, the GTK dialog setup function, and the console.c
shared between both platforms' CLI tools. Now it lives in just one
place, namely ssh/common.c where the rest of the centralised host-key
checking is done, so it'll be easier to adjust the wording in future.

This comes with some extra automation. Paragraph wrapping is no longer
done by hand in any version of these prompts. (Previously we let GTK
do the wrapping on GTK, but on Windows the resource file contained a
bunch of pre-wrapped LTEXT lines, and console.c had pre-wrapped
terminal messages.) And the dialog heights in Windows are determined
automatically based on the amount of stuff in the window.

The main idea of all this is that it'll be easier to set up more
elaborate kinds of host key prompt that deal with certificates (if,
e.g., a server sends us a certified host key which we don't trust the
CA for). But there are side benefits of this refactoring too: each
tool now reliably inserts its own appname in the prompts, and also, on
Windows the entire prompt text is copy-pastable.

Details of implementation: there's a new type SeatDialogText which
holds a set of (type, string) pairs describing the contents of a
prompt. Type codes distinguish ordinary text paragraphs, paragraphs to
be displayed prominently (like key fingerprints), the extra-bold scary
title at the top of the 'host key changed' version of the dialog, and
the various information that lives in the subsidiary 'more info' box.
ssh/common.c constructs this, and passes it to the Seat to present the
actual prompt.

In order to deal with the different UI for answering the prompt, I've
added an extra Seat method 'prompt_descriptions' which returns some
snippets of text to interpolate into the messages. ssh/common.c calls
that while it's still constructing the text, and incorporates the
resulting snippets into the SeatDialogText.

For the moment, this refactoring only affects the host key prompts.
The warnings about outmoded crypto are still done the old-fashioned
way; they probably ought to be similarly refactored to use this new
SeatDialogText system, but it's not immediately critical for the
purpose I have right now.
2022-07-07 18:05:32 +01:00

474 lines
16 KiB
C

/*
* unix/platform.h: Unix-specific inter-module stuff.
*/
#ifndef PUTTY_UNIX_PLATFORM_H
#define PUTTY_UNIX_PLATFORM_H
#include <stdio.h> /* for FILENAME_MAX */
#include <stdint.h> /* C99 int types */
#ifndef NO_LIBDL
#include <dlfcn.h> /* Dynamic library loading */
#endif /* NO_LIBDL */
#include "charset.h"
#include <sys/types.h> /* for mode_t */
#ifdef OSX_GTK
/*
* Assorted tweaks to various parts of the GTK front end which all
* need to be enabled when compiling on OS X. Because I might need the
* same tweaks on other systems in future, I don't want to
* conditionalise all of them on OSX_GTK directly, so instead, each
* one has its own name and we enable them all centrally here if
* OSX_GTK is defined at configure time.
*/
#define NOT_X_WINDOWS /* of course, all the X11 stuff should be disabled */
#define NO_PTY_PRE_INIT /* OS X gets very huffy if we try to set[ug]id */
#define SET_NONBLOCK_VIA_OPENPT /* work around missing fcntl functionality */
#define OSX_META_KEY_CONFIG /* two possible Meta keys to choose from */
/* this potential one of the Meta keys needs manual handling */
#define META_MANUAL_MASK (GDK_MOD1_MASK)
#define JUST_USE_GTK_CLIPBOARD_UTF8 /* low-level gdk_selection_* fails */
#define BUILDINFO_PLATFORM_GTK "OS X (GTK)"
#define BUILDINFO_GTK
#elif defined NOT_X_WINDOWS
#define BUILDINFO_PLATFORM_GTK "Unix (pure GTK)"
#define BUILDINFO_GTK
#else
#define BUILDINFO_PLATFORM_GTK "Unix (GTK + X11)"
#define BUILDINFO_GTK
#endif
/* BUILDINFO_PLATFORM varies its expansion between the GTK and
* pure-CLI utilities, so that Unix Plink, PSFTP etc don't announce
* themselves incongruously as having something to do with GTK. */
#define BUILDINFO_PLATFORM_CLI "Unix"
extern const bool buildinfo_gtk_relevant;
#define BUILDINFO_PLATFORM (buildinfo_gtk_relevant ? \
BUILDINFO_PLATFORM_GTK : BUILDINFO_PLATFORM_CLI)
char *buildinfo_gtk_version(void);
struct Filename {
char *path;
};
FILE *f_open(const struct Filename *, char const *, bool);
struct FontSpec {
char *name; /* may be "" to indicate no selected font at all */
};
struct FontSpec *fontspec_new(const char *name);
extern const struct BackendVtable pty_backend;
#define BROKEN_PIPE_ERROR_CODE EPIPE /* used in ssh/sharing.c */
/*
* Under GTK, we send MA_CLICK _and_ MA_2CLK, or MA_CLICK _and_
* MA_3CLK, when a button is pressed for the second or third time.
*/
#define MULTICLICK_ONLY_EVENT 0
/*
* Under GTK, there is no context help available.
*/
typedef void *HelpCtx;
#define NULL_HELPCTX ((HelpCtx)NULL)
#define HELPCTX(x) NULL
#define FILTER_KEY_FILES NULL /* FIXME */
#define FILTER_DYNLIB_FILES NULL /* FIXME */
/*
* Under X, selection data must not be NUL-terminated.
*/
#define SELECTION_NUL_TERMINATED 0
/*
* Under X, copying to the clipboard terminates lines with just LF.
*/
#define SEL_NL { 10 }
/* Simple wraparound timer function */
unsigned long getticks(void);
#define GETTICKCOUNT getticks
#define TICKSPERSEC 1000 /* we choose to use milliseconds */
#define CURSORBLINK 450 /* no standard way to set this */
#define WCHAR wchar_t
#define BYTE unsigned char
#define PLATFORM_CLIPBOARDS(X) \
X(CLIP_PRIMARY, "X11 primary selection") \
X(CLIP_CLIPBOARD, "XDG clipboard") \
X(CLIP_CUSTOM_1, "<custom#1>") \
X(CLIP_CUSTOM_2, "<custom#2>") \
X(CLIP_CUSTOM_3, "<custom#3>") \
/* end of list */
#ifdef OSX_GTK
/* OS X has no PRIMARY selection */
#define MOUSE_SELECT_CLIPBOARD CLIP_NULL
#define MOUSE_PASTE_CLIPBOARD CLIP_LOCAL
#define CLIPNAME_IMPLICIT "Last selected text"
#define CLIPNAME_EXPLICIT "System clipboard"
#define CLIPNAME_EXPLICIT_OBJECT "system clipboard"
/* These defaults are the ones that more or less comply with the OS X
* Human Interface Guidelines, i.e. copy/paste to the system clipboard
* is _not_ implicit but requires a specific UI action. This is at
* odds with all other PuTTY front ends' defaults, but on OS X there
* is no multi-decade precedent for PuTTY working the other way. */
#define CLIPUI_DEFAULT_AUTOCOPY false
#define CLIPUI_DEFAULT_MOUSE CLIPUI_IMPLICIT
#define CLIPUI_DEFAULT_INS CLIPUI_EXPLICIT
#define MENU_CLIPBOARD CLIP_CLIPBOARD
#define COPYALL_CLIPBOARDS CLIP_CLIPBOARD
#else
#define MOUSE_SELECT_CLIPBOARD CLIP_PRIMARY
#define MOUSE_PASTE_CLIPBOARD CLIP_PRIMARY
#define CLIPNAME_IMPLICIT "PRIMARY"
#define CLIPNAME_EXPLICIT "CLIPBOARD"
#define CLIPNAME_EXPLICIT_OBJECT "CLIPBOARD"
/* These defaults are the ones Unix PuTTY has historically had since
* it was first thought of in 2002 */
#define CLIPUI_DEFAULT_AUTOCOPY false
#define CLIPUI_DEFAULT_MOUSE CLIPUI_IMPLICIT
#define CLIPUI_DEFAULT_INS CLIPUI_IMPLICIT
#define MENU_CLIPBOARD CLIP_CLIPBOARD
#define COPYALL_CLIPBOARDS CLIP_PRIMARY, CLIP_CLIPBOARD
/* X11 supports arbitrary named clipboards */
#define NAMED_CLIPBOARDS
#endif
/* The per-session frontend structure managed by window.c */
typedef struct GtkFrontend GtkFrontend;
/* Callback when a dialog box finishes, and a no-op implementation of it */
typedef void (*post_dialog_fn_t)(void *ctx, int result);
void trivial_post_dialog_fn(void *vctx, int result);
/* Start up a session window, with or without a preliminary config box */
void initial_config_box(Conf *conf, post_dialog_fn_t after, void *afterctx);
void new_session_window(Conf *conf, const char *geometry_string);
/* Defined in main-gtk-*.c */
void launch_duplicate_session(Conf *conf);
void launch_new_session(void);
void launch_saved_session(const char *str);
void session_window_closed(void);
void window_setup_error(const char *errmsg);
#ifdef MAY_REFER_TO_GTK_IN_HEADERS
GtkWidget *make_gtk_toplevel_window(GtkFrontend *frontend);
#endif
const struct BackendVtable *select_backend(Conf *conf);
/* Defined in gtk-common.c */
void gtkcomm_setup(void);
/* Used to pass application-menu operations from
* main-gtk-application.c to window.c */
enum MenuAction {
MA_COPY, MA_PASTE, MA_COPY_ALL, MA_DUPLICATE_SESSION,
MA_RESTART_SESSION, MA_CHANGE_SETTINGS, MA_CLEAR_SCROLLBACK,
MA_RESET_TERMINAL, MA_EVENT_LOG
};
void app_menu_action(GtkFrontend *frontend, enum MenuAction);
/* Arrays of pixmap data used for GTK window icons. (main_icon is for
* the process's main window; cfg_icon is the modified icon used for
* its config box.) */
extern const char *const *const main_icon[];
extern const char *const *const cfg_icon[];
extern const int n_main_icon, n_cfg_icon;
/* Things dialog.c needs from window.c */
#ifdef MAY_REFER_TO_GTK_IN_HEADERS
enum DialogSlot {
DIALOG_SLOT_RECONFIGURE,
DIALOG_SLOT_NETWORK_PROMPT,
DIALOG_SLOT_LOGFILE_PROMPT,
DIALOG_SLOT_WARN_ON_CLOSE,
DIALOG_SLOT_CONNECTION_FATAL,
DIALOG_SLOT_LIMIT /* must remain last */
};
GtkWidget *gtk_seat_get_window(Seat *seat);
void register_dialog(Seat *seat, enum DialogSlot slot, GtkWidget *dialog);
void unregister_dialog(Seat *seat, enum DialogSlot slot);
void set_window_icon(GtkWidget *window, const char *const *const *icon,
int n_icon);
extern GdkAtom compound_text_atom;
#endif
/* Things window.c needs from dialog.c */
#ifdef MAY_REFER_TO_GTK_IN_HEADERS
GtkWidget *create_config_box(const char *title, Conf *conf,
bool midsession, int protcfginfo,
post_dialog_fn_t after, void *afterctx);
#endif
void nonfatal_message_box(void *window, const char *msg);
void about_box(void *window);
typedef struct eventlog_stuff eventlog_stuff;
eventlog_stuff *eventlogstuff_new(void);
void eventlogstuff_free(eventlog_stuff *);
void showeventlog(eventlog_stuff *estuff, void *parentwin);
void logevent_dlg(eventlog_stuff *estuff, const char *string);
int gtkdlg_askappend(Seat *seat, Filename *filename,
void (*callback)(void *ctx, int result), void *ctx);
SeatPromptResult gtk_seat_confirm_ssh_host_key(
Seat *seat, const char *host, int port, const char *keytype,
char *keystr, SeatDialogText *text, HelpCtx helpctx,
void (*callback)(void *ctx, SeatPromptResult result), void *ctx);
SeatPromptResult gtk_seat_confirm_weak_crypto_primitive(
Seat *seat, const char *algtype, const char *algname,
void (*callback)(void *ctx, SeatPromptResult result), void *ctx);
SeatPromptResult gtk_seat_confirm_weak_cached_hostkey(
Seat *seat, const char *algname, const char *betteralgs,
void (*callback)(void *ctx, SeatPromptResult result), void *ctx);
const SeatDialogPromptDescriptions *gtk_seat_prompt_descriptions(Seat *seat);
#ifdef MAY_REFER_TO_GTK_IN_HEADERS
struct message_box_button {
const char *title;
char shortcut;
int type; /* more negative means more appropriate to be the Esc action */
int value; /* message box's return value if this is pressed */
};
struct message_box_buttons {
const struct message_box_button *buttons;
int nbuttons;
};
extern const struct message_box_buttons buttons_yn, buttons_ok;
GtkWidget *create_message_box(
GtkWidget *parentwin, const char *title, const char *msg, int minwid,
bool selectable, const struct message_box_buttons *buttons,
post_dialog_fn_t after, void *afterctx);
#endif
void show_ca_config_box_synchronously(void);
/* window.c needs this special function in utils */
int keysym_to_unicode(int keysym);
/* Things storage.c needs from window.c */
char *x_get_default(const char *key);
/* Things storage.c provides to window.c */
void provide_xrm_string(const char *string, const char *progname);
/* Function that main-gtk-*.c needs from {pterm,putty}.c. Does
* early process setup that varies between applications (e.g.
* pty_pre_init or sk_init), and is passed a boolean by the caller
* indicating whether this is an OS X style multi-session monolithic
* process or an ordinary Unix one-shot. */
void setup(bool single_session_in_this_process);
/*
* Per-application constants that affect behaviour of shared modules.
*/
/* Do we need an Event Log menu item? (yes for PuTTY, no for pterm) */
extern const bool use_event_log;
/* Do we need a New Session menu item? (yes for PuTTY, no for pterm) */
extern const bool new_session;
/* Do we need a Saved Sessions menu item? (yes for PuTTY, no for pterm) */
extern const bool saved_sessions;
/* When we Duplicate Session, do we need to double-check that the Conf
* is in a launchable state? (no for pterm, because conf_launchable
* returns an irrelevant answer, since we'll force use of the pty
* backend which ignores all the relevant settings) */
extern const bool dup_check_launchable;
/* In the Duplicate Session serialised data, do we send/receive an
* argv array after the main Conf? (yes for pterm, no for PuTTY) */
extern const bool use_pty_argv;
/*
* OS X environment munging: this is the prefix we expect to find on
* environment variable names that were changed by osxlaunch.
* Extracted from the command line of the OS X pterm main binary, and
* used in pty.c to restore the original environment before
* launching its subprocess.
*/
extern char *pty_osx_envrestore_prefix;
/* Things provided by console.c */
struct termios;
void stderr_tty_init(void); /* call at startup if stderr might be a tty */
void premsg(struct termios *);
void postmsg(struct termios *);
/* The interface used by uxsel.c */
typedef struct uxsel_id uxsel_id;
void uxsel_init(void);
typedef void (*uxsel_callback_fn)(int fd, int event);
void uxsel_set(int fd, int rwx, uxsel_callback_fn callback);
void uxsel_del(int fd);
enum { SELECT_R = 1, SELECT_W = 2, SELECT_X = 4 };
void select_result(int fd, int event);
int first_fd(int *state, int *rwx);
int next_fd(int *state, int *rwx);
/* The following are expected to be provided _to_ uxsel.c by the frontend */
uxsel_id *uxsel_input_add(int fd, int rwx); /* returns an id */
void uxsel_input_remove(uxsel_id *id);
/* config-unix.c */
struct controlbox;
void unix_setup_config_box(
struct controlbox *b, bool midsession, int protocol);
/* config-gtk.c */
void gtk_setup_config_box(
struct controlbox *b, bool midsession, void *window);
/*
* In the Unix Unicode layer, DEFAULT_CODEPAGE is a special value
* which causes mb_to_wc and wc_to_mb to call _libc_ rather than
* libcharset. That way, we can interface the various charsets
* supported by libcharset with the one supported by mbstowcs and
* wcstombs (which will be the character set in which stuff read
* from the command line or config files is assumed to be encoded).
*/
#define DEFAULT_CODEPAGE 0xFFFF
#define CP_UTF8 CS_UTF8 /* from libcharset */
#define strnicmp strncasecmp
#define stricmp strcasecmp
/* BSD-semantics version of signal(), and another helpful function */
void (*putty_signal(int sig, void (*func)(int)))(int);
void block_signal(int sig, bool block_it);
/* utils */
void cloexec(int);
void noncloexec(int);
bool nonblock(int);
bool no_nonblock(int);
char *make_dir_and_check_ours(const char *dirname);
char *make_dir_path(const char *path, mode_t mode);
/*
* Exports from unicode.c.
*/
bool init_ucs(struct unicode_data *ucsdata, char *line_codepage,
bool utf8_override, int font_charset, int vtmode);
/*
* Spare functions exported directly from network.c.
*/
void *sk_getxdmdata(Socket *sock, int *lenp);
int sk_net_get_fd(Socket *sock);
SockAddr *unix_sock_addr(const char *path);
Socket *new_unix_listener(SockAddr *listenaddr, Plug *plug);
/*
* General helpful Unix stuff: more helpful version of the FD_SET
* macro, which also handles maxfd.
*/
#define FD_SET_MAX(fd, max, set) do { \
FD_SET(fd, &set); \
if (max < fd + 1) max = fd + 1; \
} while (0)
/*
* Exports from serial.c.
*/
extern const struct BackendVtable serial_backend;
/*
* peerinfo.c, wrapping getsockopt(SO_PEERCRED).
*/
bool so_peercred(int fd, int *pid, int *uid, int *gid);
/*
* fd-socket.c.
*/
Socket *make_fd_socket(int infd, int outfd, int inerrfd,
SockAddr *addr, int port, Plug *plug);
Socket *make_deferred_fd_socket(DeferredSocketOpener *opener,
SockAddr *addr, int port, Plug *plug);
void setup_fd_socket(Socket *s, int infd, int outfd, int inerrfd);
/*
* Default font setting, which can vary depending on NOT_X_WINDOWS.
*/
#ifdef NOT_X_WINDOWS
#define DEFAULT_GTK_FONT "client:Monospace 12"
#else
#define DEFAULT_GTK_FONT "server:fixed"
#endif
/*
* pty.c.
*/
void pty_pre_init(void); /* pty+utmp setup before dropping privilege */
/* Pass in the argv[] for an instance of the pty backend created by
* the standard vtable constructor. Only called from (non-OSX) pterm,
* which will construct exactly one such instance, and initialises
* this from the command line. */
extern char **pty_argv;
/*
* askpass.c.
*/
char *gtk_askpass_main(const char *display, const char *wintitle,
const char *prompt, bool *success);
/*
* procnet.c.
*/
bool socket_peer_is_same_user(int fd);
static inline bool sk_peer_trusted(Socket *sock)
{
int fd = sk_net_get_fd(sock);
return fd >= 0 && socket_peer_is_same_user(fd);
}
/*
* sftpserver.c.
*/
extern const SftpServerVtable unix_live_sftpserver_vt;
/*
* utils/pollwrap.c.
*/
typedef struct pollwrapper pollwrapper;
pollwrapper *pollwrap_new(void);
void pollwrap_free(pollwrapper *pw);
void pollwrap_clear(pollwrapper *pw);
void pollwrap_add_fd_events(pollwrapper *pw, int fd, int events);
void pollwrap_add_fd_rwx(pollwrapper *pw, int fd, int rwx);
int pollwrap_poll_instant(pollwrapper *pw);
int pollwrap_poll_endless(pollwrapper *pw);
int pollwrap_poll_timeout(pollwrapper *pw, int milliseconds);
int pollwrap_get_fd_events(pollwrapper *pw, int fd);
int pollwrap_get_fd_rwx(pollwrapper *pw, int fd);
static inline bool pollwrap_check_fd_rwx(pollwrapper *pw, int fd, int rwx)
{
return (pollwrap_get_fd_rwx(pw, fd) & rwx) != 0;
}
/*
* cliloop.c.
*/
typedef bool (*cliloop_pw_setup_t)(void *ctx, pollwrapper *pw);
typedef void (*cliloop_pw_check_t)(void *ctx, pollwrapper *pw);
typedef bool (*cliloop_continue_t)(void *ctx, bool found_any_fd,
bool ran_any_callback);
void cli_main_loop(cliloop_pw_setup_t pw_setup,
cliloop_pw_check_t pw_check,
cliloop_continue_t cont, void *ctx);
bool cliloop_no_pw_setup(void *ctx, pollwrapper *pw);
void cliloop_no_pw_check(void *ctx, pollwrapper *pw);
bool cliloop_always_continue(void *ctx, bool, bool);
/* network.c: network error reporting helper taking an OS error code */
void plug_closing_errno(Plug *plug, int error);
SeatPromptResult make_spr_sw_abort_errno(const char *prefix, int errno_value);
#endif /* PUTTY_UNIX_PLATFORM_H */