Attachment #3347 for bug #69




char *
read_passphrase(const char *prompt, int flags)
{
	static const int askpass_never = 0, askpass_always = 1, askpass_auto = 2;
	static const char *prefix_never = "never:", *prefix_always = "always:",
		*prefix_auto = "auto:";

	char cr = '\r', *askpass = NULL, *ret, buf[1024];
	int rppflags, use_askpass, force_askpass, ttyfd;

	/* decode $SSH_ASKPASS */
	askpass = getenv(SSH_ASKPASS_ENV);

	if(askpass == NULL) {
		force_askpass = askpass_auto;
		askpass = "";
	} else if(strncmp(askpass, prefix_never, strlen(prefix_never)) == 0) {
		force_askpass = askpass_never;
		askpass += strlen(prefix_never);
	} else if(strncmp(askpass, prefix_always, strlen(prefix_always)) == 0) {
		force_askpass = askpass_always;
		askpass += strlen(prefix_always);
	} else if(strncmp(askpass, prefix_auto, strlen(prefix_auto)) == 0) {
		force_askpass = askpass_auto;
		askpass += strlen(prefix_auto);
	} else
		force_askpass = askpass_auto;

	if(askpass[0] == '\0')
		askpass = _PATH_SSH_ASKPASS_DEFAULT;

	if (force_askpass == askpass_always)
	if (flags & RP_USE_ASKPASS)
		use_askpass = 1;
	else {
		/* This block has two purposes:
			1.) automatic detection of askpass usesage.  The result will be stored
			    in use_askpass and may be overridden by force_askpass == never
			2.) determine options and print debug warnings for use with the
			    tty/stdin pasphrase reader.
		*/
		use_askpass = 0;

		rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF;
		if (flags & RP_USE_ASKPASS)
			use_askpass = 1;
		else if (flags & RP_ALLOW_STDIN) {
			if (!isatty(STDIN_FILENO)) {
				debug("read_passphrase: stdin is not a tty");
				use_askpass = 1;
			}
			/*
			 * If we're on a tty, ensure that show the prompt at
			 * the beginning of the line. This will hopefully
			 * clobber any password characters the user has
			 * optimistically typed before echo is disabled.
			 */
			(void)write(ttyfd, &cr, 1);
			close(ttyfd);
		} else {
			rppflags |= RPP_REQUIRE_TTY;
			ttyfd = open(_PATH_TTY, O_RDWR);
			if (ttyfd >= 0)
				close(ttyfd);
			else {
				debug("read_passphrase: can't open %s: %s", _PATH_TTY,
					strerror(errno));
				use_askpass = 1;
			}
		}

		if(getenv("DISPLAY") == NULL)
			use_askpass = 0;

		if(force_askpass == askpass_never)
			use_askpass = 0;
	}

	if (!use_askpass && (flags & RP_USE_ASKPASS))
		return (flags & RP_ALLOW_EOF) ? NULL : xstrdup("");

	if (use_askpass) {
		if (getenv(SSH_ASKPASS_ENV))
			askpass = getenv(SSH_ASKPASS_ENV);
		else
			askpass = _PATH_SSH_ASKPASS_DEFAULT;
		if ((ret = ssh_askpass(askpass, prompt)) == NULL)
			if (!(flags & RP_ALLOW_EOF))
				return xstrdup("");
		return ret;
	} else {
		if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL) {
			if (flags & RP_ALLOW_EOF)
				return NULL;
			return xstrdup("");
		}
		ret = xstrdup(buf);
		memset(buf, 'x', sizeof buf);
		return ret;
	}

	if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL) {
		if (flags & RP_ALLOW_EOF)
			return NULL;
		return xstrdup("");
	}

	ret = xstrdup(buf);
	explicit_bzero(buf, sizeof(buf));
	return ret;
}

int

Return to bug 69

Lines 117-175 Link Here

(-)a/readpass.c (-38 / +69 lines)
117	char *	117	char *
118	read_passphrase(const char *prompt, int flags)	118	read_passphrase(const char *prompt, int flags)
119	{	119	{
		120	static const int askpass_never = 0, askpass_always = 1, askpass_auto = 2;
		121	static const char prefix_never = "never:", prefix_always = "always:",
		122	*prefix_auto = "auto:";
		123
120	char cr = '\r', askpass = NULL, ret, buf[1024];	124	char cr = '\r', askpass = NULL, ret, buf[1024];
121	int rppflags, use_askpass = 0, ttyfd;	125	int rppflags, use_askpass, force_askpass, ttyfd;
		126
		127	/* decode $SSH_ASKPASS */
		128	askpass = getenv(SSH_ASKPASS_ENV);
		129
		130	if(askpass == NULL) {
		131	force_askpass = askpass_auto;
		132	askpass = "";
		133	} else if(strncmp(askpass, prefix_never, strlen(prefix_never)) == 0) {
		134	force_askpass = askpass_never;
		135	askpass += strlen(prefix_never);
		136	} else if(strncmp(askpass, prefix_always, strlen(prefix_always)) == 0) {
		137	force_askpass = askpass_always;
		138	askpass += strlen(prefix_always);
		139	} else if(strncmp(askpass, prefix_auto, strlen(prefix_auto)) == 0) {
		140	force_askpass = askpass_auto;
		141	askpass += strlen(prefix_auto);
		142	} else
		143	force_askpass = askpass_auto;
		144
		145	if(askpass[0] == '\0')
		146	askpass = _PATH_SSH_ASKPASS_DEFAULT;
122		147
123	rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF;	148	if (force_askpass == askpass_always)
124	if (flags & RP_USE_ASKPASS)
125	use_askpass = 1;	149	use_askpass = 1;
126	else if (flags & RP_ALLOW_STDIN) {	150	else {
127	if (!isatty(STDIN_FILENO)) {	151	/* This block has two purposes:
128	debug("read_passphrase: stdin is not a tty");	152	1.) automatic detection of askpass usesage. The result will be stored
		153	in use_askpass and may be overridden by force_askpass == never
		154	2.) determine options and print debug warnings for use with the
		155	tty/stdin pasphrase reader.
		156	*/
		157	use_askpass = 0;
		158
		159	rppflags = (flags & RP_ECHO) ? RPP_ECHO_ON : RPP_ECHO_OFF;
		160	if (flags & RP_USE_ASKPASS)
129	use_askpass = 1;	161	use_askpass = 1;
130	}	162	else if (flags & RP_ALLOW_STDIN) {
131	} else {	163	if (!isatty(STDIN_FILENO)) {
132	rppflags \|= RPP_REQUIRE_TTY;	164	debug("read_passphrase: stdin is not a tty");
133	ttyfd = open(_PATH_TTY, O_RDWR);	165	use_askpass = 1;
134	if (ttyfd >= 0) {	166	}
135	/*
136	* If we're on a tty, ensure that show the prompt at
137	* the beginning of the line. This will hopefully
138	* clobber any password characters the user has
139	* optimistically typed before echo is disabled.
140	*/
141	(void)write(ttyfd, &cr, 1);
142	close(ttyfd);
143	} else {	167	} else {
144	debug("read_passphrase: can't open %s: %s", _PATH_TTY,	168	rppflags \|= RPP_REQUIRE_TTY;
145	strerror(errno));	169	ttyfd = open(_PATH_TTY, O_RDWR);
146	use_askpass = 1;	170	if (ttyfd >= 0)
		171	close(ttyfd);
		172	else {
		173	debug("read_passphrase: can't open %s: %s", _PATH_TTY,
		174	strerror(errno));
		175	use_askpass = 1;
		176	}
147	}	177	}
		178
		179	if(getenv("DISPLAY") == NULL)
		180	use_askpass = 0;
		181
		182	if(force_askpass == askpass_never)
		183	use_askpass = 0;
148	}	184	}
149		185
150	if ((flags & RP_USE_ASKPASS) && getenv("DISPLAY") == NULL)	186	if (!use_askpass && (flags & RP_USE_ASKPASS))
151	return (flags & RP_ALLOW_EOF) ? NULL : xstrdup("");	187	return (flags & RP_ALLOW_EOF) ? NULL : xstrdup("");
152		188
153	if (use_askpass && getenv("DISPLAY")) {	189	if (use_askpass) {
154	if (getenv(SSH_ASKPASS_ENV))
155	askpass = getenv(SSH_ASKPASS_ENV);
156	else
157	askpass = _PATH_SSH_ASKPASS_DEFAULT;
158	if ((ret = ssh_askpass(askpass, prompt)) == NULL)	190	if ((ret = ssh_askpass(askpass, prompt)) == NULL)
159	if (!(flags & RP_ALLOW_EOF))	191	if (!(flags & RP_ALLOW_EOF))
160	return xstrdup("");	192	return xstrdup("");
161	return ret;	193	return ret;
		194	} else {
		195	if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL) {
		196	if (flags & RP_ALLOW_EOF)
		197	return NULL;
		198	return xstrdup("");
		199	}
		200	ret = xstrdup(buf);
		201	memset(buf, 'x', sizeof buf);
		202	return ret;
162	}	203	}
163
164	if (readpassphrase(prompt, buf, sizeof buf, rppflags) == NULL) {
165	if (flags & RP_ALLOW_EOF)
166	return NULL;
167	return xstrdup("");
168	}
169
170	ret = xstrdup(buf);
171	explicit_bzero(buf, sizeof(buf));
172	return ret;
173	}	204	}
174		205
175	int	206	int