[u/mdw/putty] / unix / uxcons.c

/*
 * uxcons.c: various interactive-prompt routines shared between the
 * Unix console PuTTY tools
 */

#include <stdio.h>
#include <stdlib.h>
#include <stdarg.h>
#include <assert.h>
#include <termios.h>
#include <unistd.h>

#include "putty.h"
#include "storage.h"
#include "ssh.h"

int console_batch_mode = FALSE;

static void *console_logctx = NULL;

/*
 * Clean up and exit.
 */
void cleanup_exit(int code)
{
    /*
     * Clean up.
     */
    sk_cleanup();
    random_save_seed();
    exit(code);
}

void set_busy_status(void *frontend, int status)
{
}

void update_specials_menu(void *frontend)
{
}

void notify_remote_exit(void *frontend)
{
}

void timer_change_notify(long next)
{
}

int verify_ssh_host_key(void *frontend, char *host, int port, char *keytype,
                        char *keystr, char *fingerprint,
                        void (*callback)(void *ctx, int result), void *ctx)
{
    int ret;

    static const char absentmsg_batch[] =
	"The server's host key is not cached. You have no guarantee\n"
	"that the server is the computer you think it is.\n"
	"The server's %s key fingerprint is:\n"
	"%s\n"
	"Connection abandoned.\n";
    static const char absentmsg[] =
	"The server's host key is not cached. You have no guarantee\n"
	"that the server is the computer you think it is.\n"
	"The server's %s key fingerprint is:\n"
	"%s\n"
	"If you trust this host, enter \"y\" to add the key to\n"
	"PuTTY's cache and carry on connecting.\n"
	"If you want to carry on connecting just once, without\n"
	"adding the key to the cache, enter \"n\".\n"
	"If you do not trust this host, press Return to abandon the\n"
	"connection.\n"
	"Store key in cache? (y/n) ";

    static const char wrongmsg_batch[] =
	"WARNING - POTENTIAL SECURITY BREACH!\n"
	"The server's host key does not match the one PuTTY has\n"
	"cached. This means that either the server administrator\n"
	"has changed the host key, or you have actually connected\n"
	"to another computer pretending to be the server.\n"
	"The new %s key fingerprint is:\n"
	"%s\n"
	"Connection abandoned.\n";
    static const char wrongmsg[] =
	"WARNING - POTENTIAL SECURITY BREACH!\n"
	"The server's host key does not match the one PuTTY has\n"
	"cached. This means that either the server administrator\n"
	"has changed the host key, or you have actually connected\n"
	"to another computer pretending to be the server.\n"
	"The new %s key fingerprint is:\n"
	"%s\n"
	"If you were expecting this change and trust the new key,\n"
	"enter \"y\" to update PuTTY's cache and continue connecting.\n"
	"If you want to carry on connecting but without updating\n"
	"the cache, enter \"n\".\n"
	"If you want to abandon the connection completely, press\n"
	"Return to cancel. Pressing Return is the ONLY guaranteed\n"
	"safe choice.\n"
	"Update cached key? (y/n, Return cancels connection) ";

    static const char abandoned[] = "Connection abandoned.\n";

    char line[32];

    /*
     * Verify the key.
     */
    ret = verify_host_key(host, port, keytype, keystr);

    if (ret == 0)		       /* success - key matched OK */
	return 1;

    if (ret == 2) {		       /* key was different */
	if (console_batch_mode) {
	    fprintf(stderr, wrongmsg_batch, keytype, fingerprint);
	    return 0;
	}
	fprintf(stderr, wrongmsg, keytype, fingerprint);
	fflush(stderr);
    }
    if (ret == 1) {		       /* key was absent */
	if (console_batch_mode) {
	    fprintf(stderr, absentmsg_batch, keytype, fingerprint);
	    return 0;
	}
	fprintf(stderr, absentmsg, keytype, fingerprint);
	fflush(stderr);
    }

    {
	struct termios oldmode, newmode;
	tcgetattr(0, &oldmode);
	newmode = oldmode;
	newmode.c_lflag |= ECHO | ISIG | ICANON;
	tcsetattr(0, TCSANOW, &newmode);
	line[0] = '\0';
	read(0, line, sizeof(line) - 1);
	tcsetattr(0, TCSANOW, &oldmode);
    }

    if (line[0] != '\0' && line[0] != '\r' && line[0] != '\n') {
	if (line[0] == 'y' || line[0] == 'Y')
	    store_host_key(host, port, keytype, keystr);
        return 1;
    } else {
	fprintf(stderr, abandoned);
        return 0;
    }
}

/*
 * Ask whether the selected algorithm is acceptable (since it was
 * below the configured 'warn' threshold).
 */
int askalg(void *frontend, const char *algtype, const char *algname,
	   void (*callback)(void *ctx, int result), void *ctx)
{
    static const char msg[] =
	"The first %s supported by the server is\n"
	"%s, which is below the configured warning threshold.\n"
	"Continue with connection? (y/n) ";
    static const char msg_batch[] =
	"The first %s supported by the server is\n"
	"%s, which is below the configured warning threshold.\n"
	"Connection abandoned.\n";
    static const char abandoned[] = "Connection abandoned.\n";

    char line[32];

    if (console_batch_mode) {
	fprintf(stderr, msg_batch, algtype, algname);
	return 0;
    }

    fprintf(stderr, msg, algtype, algname);
    fflush(stderr);

    {
	struct termios oldmode, newmode;
	tcgetattr(0, &oldmode);
	newmode = oldmode;
	newmode.c_lflag |= ECHO | ISIG | ICANON;
	tcsetattr(0, TCSANOW, &newmode);
	line[0] = '\0';
	read(0, line, sizeof(line) - 1);
	tcsetattr(0, TCSANOW, &oldmode);
    }

    if (line[0] == 'y' || line[0] == 'Y') {
	return 1;
    } else {
	fprintf(stderr, abandoned);
	return 0;
    }
}

/*
 * Ask whether to wipe a session log file before writing to it.
 * Returns 2 for wipe, 1 for append, 0 for cancel (don't log).
 */
int askappend(void *frontend, Filename filename,
	      void (*callback)(void *ctx, int result), void *ctx)
{
    static const char msgtemplate[] =
	"The session log file \"%.*s\" already exists.\n"
	"You can overwrite it with a new session log,\n"
	"append your session log to the end of it,\n"
	"or disable session logging for this session.\n"
	"Enter \"y\" to wipe the file, \"n\" to append to it,\n"
	"or just press Return to disable logging.\n"
	"Wipe the log file? (y/n, Return cancels logging) ";

    static const char msgtemplate_batch[] =
	"The session log file \"%.*s\" already exists.\n"
	"Logging will not be enabled.\n";

    char line[32];

    if (console_batch_mode) {
	fprintf(stderr, msgtemplate_batch, FILENAME_MAX, filename.path);
	fflush(stderr);
	return 0;
    }
    fprintf(stderr, msgtemplate, FILENAME_MAX, filename.path);
    fflush(stderr);

    {
	struct termios oldmode, newmode;
	tcgetattr(0, &oldmode);
	newmode = oldmode;
	newmode.c_lflag |= ECHO | ISIG | ICANON;
	tcsetattr(0, TCSANOW, &newmode);
	line[0] = '\0';
	read(0, line, sizeof(line) - 1);
	tcsetattr(0, TCSANOW, &oldmode);
    }

    if (line[0] == 'y' || line[0] == 'Y')
	return 2;
    else if (line[0] == 'n' || line[0] == 'N')
	return 1;
    else
	return 0;
}

/*
 * Warn about the obsolescent key file format.
 * 
 * Uniquely among these functions, this one does _not_ expect a
 * frontend handle. This means that if PuTTY is ported to a
 * platform which requires frontend handles, this function will be
 * an anomaly. Fortunately, the problem it addresses will not have
 * been present on that platform, so it can plausibly be
 * implemented as an empty function.
 */
void old_keyfile_warning(void)
{
    static const char message[] =
	"You are loading an SSH 2 private key which has an\n"
	"old version of the file format. This means your key\n"
	"file is not fully tamperproof. Future versions of\n"
	"PuTTY may stop supporting this private key format,\n"
	"so we recommend you convert your key to the new\n"
	"format.\n"
	"\n"
	"Once the key is loaded into PuTTYgen, you can perform\n"
	"this conversion simply by saving it again.\n";

    fputs(message, stderr);
}

void console_provide_logctx(void *logctx)
{
    console_logctx = logctx;
}

void logevent(void *frontend, const char *string)
{
    if (console_logctx)
	log_eventlog(console_logctx, string);
}

int console_get_line(const char *prompt, char *str,
		     int maxlen, int is_pw)
{
    struct termios oldmode, newmode;
    int i;

    if (console_batch_mode) {
	if (maxlen > 0)
	    str[0] = '\0';
	return 0;
    } else {
	tcgetattr(0, &oldmode);
	newmode = oldmode;
	newmode.c_lflag |= ISIG | ICANON;
	if (is_pw)
	    newmode.c_lflag &= ~ECHO;
	else
	    newmode.c_lflag |= ECHO;
	tcsetattr(0, TCSANOW, &newmode);

	fputs(prompt, stdout);
	fflush(stdout);
	i = read(0, str, maxlen - 1);

	tcsetattr(0, TCSANOW, &oldmode);

	if (i > 0 && str[i-1] == '\n')
	    i--;
	str[i] = '\0';

	if (is_pw)
	    fputs("\n", stdout);

	return 1;
    }
}

void frontend_keypress(void *handle)
{
    /*
     * This is nothing but a stub, in console code.
     */
    return;
}

int is_interactive(void)
{
    return isatty(0);
}

/*
 * X11-forwarding-related things suitable for console.
 */

const char platform_x11_best_transport[] = "unix";

char *platform_get_x_display(void) {
    return dupstr(getenv("DISPLAY"));
}
Commit	Line	Data
c5e438ec	1	/*
	2	* uxcons.c: various interactive-prompt routines shared between the
	3	* Unix console PuTTY tools
	4	*/
	5
	6	#include <stdio.h>
	7	#include <stdlib.h>
	8	#include <stdarg.h>
	9	#include <assert.h>
	10	#include <termios.h>
	11	#include <unistd.h>
	12
	13	#include "putty.h"
	14	#include "storage.h"
	15	#include "ssh.h"
	16
	17	int console_batch_mode = FALSE;
	18
b51259f6	19	static void *console_logctx = NULL;
b51259f6	20
c5e438ec	21	/*
	22	* Clean up and exit.
	23	*/
	24	void cleanup_exit(int code)
	25	{
	26	/*
	27	* Clean up.
	28	*/
	29	sk_cleanup();
e85da6a5	30	random_save_seed();
c5e438ec	31	exit(code);
	32	}
	33
755e0524	34	void set_busy_status(void *frontend, int status)
	35	{
	36	}
	37
125105d1	38	void update_specials_menu(void *frontend)
	39	{
	40	}
	41
39934deb	42	void notify_remote_exit(void *frontend)
	43	{
	44	}
	45
	46	void timer_change_notify(long next)
	47	{
	48	}
	49
3d9449a1	50	int verify_ssh_host_key(void frontend, char host, int port, char *keytype,
	51	char keystr, char fingerprint,
	52	void (callback)(void ctx, int result), void *ctx)
c5e438ec	53	{
	54	int ret;
	55
	56	static const char absentmsg_batch[] =
	57	"The server's host key is not cached. You have no guarantee\n"
	58	"that the server is the computer you think it is.\n"
65f66c88	59	"The server's %s key fingerprint is:\n"
c5e438ec	60	"%s\n"
	61	"Connection abandoned.\n";
	62	static const char absentmsg[] =
	63	"The server's host key is not cached. You have no guarantee\n"
	64	"that the server is the computer you think it is.\n"
65f66c88	65	"The server's %s key fingerprint is:\n"
c5e438ec	66	"%s\n"
	67	"If you trust this host, enter \"y\" to add the key to\n"
	68	"PuTTY's cache and carry on connecting.\n"
	69	"If you want to carry on connecting just once, without\n"
	70	"adding the key to the cache, enter \"n\".\n"
	71	"If you do not trust this host, press Return to abandon the\n"
	72	"connection.\n"
	73	"Store key in cache? (y/n) ";
	74
	75	static const char wrongmsg_batch[] =
	76	"WARNING - POTENTIAL SECURITY BREACH!\n"
	77	"The server's host key does not match the one PuTTY has\n"
	78	"cached. This means that either the server administrator\n"
	79	"has changed the host key, or you have actually connected\n"
	80	"to another computer pretending to be the server.\n"
65f66c88	81	"The new %s key fingerprint is:\n"
c5e438ec	82	"%s\n"
	83	"Connection abandoned.\n";
	84	static const char wrongmsg[] =
	85	"WARNING - POTENTIAL SECURITY BREACH!\n"
	86	"The server's host key does not match the one PuTTY has\n"
	87	"cached. This means that either the server administrator\n"
	88	"has changed the host key, or you have actually connected\n"
	89	"to another computer pretending to be the server.\n"
65f66c88	90	"The new %s key fingerprint is:\n"
c5e438ec	91	"%s\n"
	92	"If you were expecting this change and trust the new key,\n"
	93	"enter \"y\" to update PuTTY's cache and continue connecting.\n"
	94	"If you want to carry on connecting but without updating\n"
	95	"the cache, enter \"n\".\n"
	96	"If you want to abandon the connection completely, press\n"
	97	"Return to cancel. Pressing Return is the ONLY guaranteed\n"
	98	"safe choice.\n"
	99	"Update cached key? (y/n, Return cancels connection) ";
	100
	101	static const char abandoned[] = "Connection abandoned.\n";
	102
	103	char line[32];
	104
	105	/*
	106	* Verify the key.
	107	*/
	108	ret = verify_host_key(host, port, keytype, keystr);
	109
	110	if (ret == 0) /* success - key matched OK */
3d9449a1	111	return 1;
c5e438ec	112
	113	if (ret == 2) { /* key was different */
	114	if (console_batch_mode) {
65f66c88	115	fprintf(stderr, wrongmsg_batch, keytype, fingerprint);
3d9449a1	116	return 0;
c5e438ec	117	}
65f66c88	118	fprintf(stderr, wrongmsg, keytype, fingerprint);
c5e438ec	119	fflush(stderr);
	120	}
	121	if (ret == 1) { /* key was absent */
	122	if (console_batch_mode) {
65f66c88	123	fprintf(stderr, absentmsg_batch, keytype, fingerprint);
3d9449a1	124	return 0;
c5e438ec	125	}
65f66c88	126	fprintf(stderr, absentmsg, keytype, fingerprint);
c5e438ec	127	fflush(stderr);
	128	}
	129
	130	{
	131	struct termios oldmode, newmode;
	132	tcgetattr(0, &oldmode);
	133	newmode = oldmode;
	134	newmode.c_lflag \|= ECHO \| ISIG \| ICANON;
	135	tcsetattr(0, TCSANOW, &newmode);
	136	line[0] = '\0';
	137	read(0, line, sizeof(line) - 1);
	138	tcsetattr(0, TCSANOW, &oldmode);
	139	}
	140
	141	if (line[0] != '\0' && line[0] != '\r' && line[0] != '\n') {
	142	if (line[0] == 'y' \|\| line[0] == 'Y')
	143	store_host_key(host, port, keytype, keystr);
3d9449a1	144	return 1;
c5e438ec	145	} else {
c5e438ec	146	fprintf(stderr, abandoned);
3d9449a1	147	return 0;
c5e438ec	148	}
	149	}
	150
	151	/*
83e7d008	152	* Ask whether the selected algorithm is acceptable (since it was
c5e438ec	153	* below the configured 'warn' threshold).
c5e438ec	154	*/
3d9449a1	155	int askalg(void frontend, const char algtype, const char *algname,
3d9449a1	156	void (callback)(void ctx, int result), void *ctx)
c5e438ec	157	{
c5e438ec	158	static const char msg[] =
83e7d008	159	"The first %s supported by the server is\n"
c5e438ec	160	"%s, which is below the configured warning threshold.\n"
	161	"Continue with connection? (y/n) ";
	162	static const char msg_batch[] =
83e7d008	163	"The first %s supported by the server is\n"
c5e438ec	164	"%s, which is below the configured warning threshold.\n"
	165	"Connection abandoned.\n";
	166	static const char abandoned[] = "Connection abandoned.\n";
	167
	168	char line[32];
	169
	170	if (console_batch_mode) {
83e7d008	171	fprintf(stderr, msg_batch, algtype, algname);
3d9449a1	172	return 0;
c5e438ec	173	}
c5e438ec	174
83e7d008	175	fprintf(stderr, msg, algtype, algname);
c5e438ec	176	fflush(stderr);
	177
	178	{
	179	struct termios oldmode, newmode;
	180	tcgetattr(0, &oldmode);
	181	newmode = oldmode;
	182	newmode.c_lflag \|= ECHO \| ISIG \| ICANON;
	183	tcsetattr(0, TCSANOW, &newmode);
	184	line[0] = '\0';
	185	read(0, line, sizeof(line) - 1);
	186	tcsetattr(0, TCSANOW, &oldmode);
	187	}
	188
	189	if (line[0] == 'y' \|\| line[0] == 'Y') {
3d9449a1	190	return 1;
c5e438ec	191	} else {
c5e438ec	192	fprintf(stderr, abandoned);
3d9449a1	193	return 0;
c5e438ec	194	}
	195	}
	196
	197	/*
	198	* Ask whether to wipe a session log file before writing to it.
	199	* Returns 2 for wipe, 1 for append, 0 for cancel (don't log).
	200	*/
919baedb	201	int askappend(void *frontend, Filename filename,
919baedb	202	void (callback)(void ctx, int result), void *ctx)
c5e438ec	203	{
	204	static const char msgtemplate[] =
	205	"The session log file \"%.*s\" already exists.\n"
	206	"You can overwrite it with a new session log,\n"
	207	"append your session log to the end of it,\n"
	208	"or disable session logging for this session.\n"
	209	"Enter \"y\" to wipe the file, \"n\" to append to it,\n"
	210	"or just press Return to disable logging.\n"
	211	"Wipe the log file? (y/n, Return cancels logging) ";
	212
	213	static const char msgtemplate_batch[] =
	214	"The session log file \"%.*s\" already exists.\n"
	215	"Logging will not be enabled.\n";
	216
	217	char line[32];
	218
c5e438ec	219	if (console_batch_mode) {
9a30e26b	220	fprintf(stderr, msgtemplate_batch, FILENAME_MAX, filename.path);
c5e438ec	221	fflush(stderr);
	222	return 0;
	223	}
9a30e26b	224	fprintf(stderr, msgtemplate, FILENAME_MAX, filename.path);
c5e438ec	225	fflush(stderr);
	226
	227	{
	228	struct termios oldmode, newmode;
	229	tcgetattr(0, &oldmode);
	230	newmode = oldmode;
	231	newmode.c_lflag \|= ECHO \| ISIG \| ICANON;
	232	tcsetattr(0, TCSANOW, &newmode);
	233	line[0] = '\0';
	234	read(0, line, sizeof(line) - 1);
	235	tcsetattr(0, TCSANOW, &oldmode);
	236	}
	237
	238	if (line[0] == 'y' \|\| line[0] == 'Y')
	239	return 2;
	240	else if (line[0] == 'n' \|\| line[0] == 'N')
	241	return 1;
	242	else
	243	return 0;
	244	}
	245
	246	/*
	247	* Warn about the obsolescent key file format.
	248	*
	249	* Uniquely among these functions, this one does _not_ expect a
	250	* frontend handle. This means that if PuTTY is ported to a
	251	* platform which requires frontend handles, this function will be
	252	* an anomaly. Fortunately, the problem it addresses will not have
	253	* been present on that platform, so it can plausibly be
	254	* implemented as an empty function.
	255	*/
	256	void old_keyfile_warning(void)
	257	{
	258	static const char message[] =
	259	"You are loading an SSH 2 private key which has an\n"
	260	"old version of the file format. This means your key\n"
	261	"file is not fully tamperproof. Future versions of\n"
	262	"PuTTY may stop supporting this private key format,\n"
	263	"so we recommend you convert your key to the new\n"
	264	"format.\n"
	265	"\n"
	266	"Once the key is loaded into PuTTYgen, you can perform\n"
	267	"this conversion simply by saving it again.\n";
	268
	269	fputs(message, stderr);
	270	}
	271
b51259f6	272	void console_provide_logctx(void *logctx)
	273	{
	274	console_logctx = logctx;
	275	}
	276
cbe2d68f	277	void logevent(void frontend, const char string)
c5e438ec	278	{
b51259f6	279	if (console_logctx)
b51259f6	280	log_eventlog(console_logctx, string);
c5e438ec	281	}
	282
	283	int console_get_line(const char prompt, char str,
	284	int maxlen, int is_pw)
	285	{
	286	struct termios oldmode, newmode;
	287	int i;
	288
	289	if (console_batch_mode) {
	290	if (maxlen > 0)
	291	str[0] = '\0';
a21a6a9a	292	return 0;
c5e438ec	293	} else {
	294	tcgetattr(0, &oldmode);
	295	newmode = oldmode;
	296	newmode.c_lflag \|= ISIG \| ICANON;
	297	if (is_pw)
	298	newmode.c_lflag &= ~ECHO;
	299	else
	300	newmode.c_lflag \|= ECHO;
	301	tcsetattr(0, TCSANOW, &newmode);
	302
	303	fputs(prompt, stdout);
	304	fflush(stdout);
	305	i = read(0, str, maxlen - 1);
	306
	307	tcsetattr(0, TCSANOW, &oldmode);
	308
	309	if (i > 0 && str[i-1] == '\n')
	310	i--;
	311	str[i] = '\0';
	312
	313	if (is_pw)
8d69b472	314	fputs("\n", stdout);
a21a6a9a	315
a21a6a9a	316	return 1;
c5e438ec	317	}
c5e438ec	318	}
	319
	320	void frontend_keypress(void *handle)
	321	{
	322	/*
	323	* This is nothing but a stub, in console code.
	324	*/
	325	return;
	326	}
47a6b94c	327
	328	int is_interactive(void)
	329	{
	330	return isatty(0);
	331	}
46ed7b64	332
	333	/*
	334	* X11-forwarding-related things suitable for console.
	335	*/
	336
	337	const char platform_x11_best_transport[] = "unix";
	338
	339	char *platform_get_x_display(void) {
	340	return dupstr(getenv("DISPLAY"));
	341	}