[openssh.git] / auth-pam.c

/*-
 * Copyright (c) 2002 Networks Associates Technology, Inc.
 * All rights reserved.
 *
 * This software was developed for the FreeBSD Project by ThinkSec AS and
 * NAI Labs, the Security Research Division of Network Associates, Inc.
 * under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
 * DARPA CHATS research program.
 *
 * 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 AND CONTRIBUTORS ``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 OR CONTRIBUTORS 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.
 */

/* Based on $FreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.11 2003/03/31 13:48:18 des Exp $ */
#include "includes.h"
RCSID("$Id$");

#ifdef USE_PAM
#include <security/pam_appl.h>

#include "auth.h"
#include "auth-pam.h"
#include "buffer.h"
#include "bufaux.h"
#include "canohost.h"
#include "log.h"
#include "monitor_wrap.h"
#include "msg.h"
#include "packet.h"
#include "readpass.h"
#include "servconf.h"
#include "ssh2.h"
#include "xmalloc.h"
#include "auth-options.h"

extern ServerOptions options;

#define __unused

#ifdef USE_POSIX_THREADS
#include <pthread.h>
/*
 * Avoid namespace clash when *not* using pthreads for systems *with* 
 * pthreads, which unconditionally define pthread_t via sys/types.h 
 * (e.g. Linux)
 */
typedef pthread_t sp_pthread_t; 
#else
/*
 * Simulate threads with processes.
 */
typedef pid_t sp_pthread_t;

static void
pthread_exit(void *value __unused)
{
	_exit(0);
}

static int
pthread_create(sp_pthread_t *thread, const void *attr __unused,
    void *(*thread_start)(void *), void *arg)
{
	pid_t pid;

	switch ((pid = fork())) {
	case -1:
		error("fork(): %s", strerror(errno));
		return (-1);
	case 0:
		thread_start(arg);
		_exit(1);
	default:
		*thread = pid;
		return (0);
	}
}

static int
pthread_cancel(sp_pthread_t thread)
{
	return (kill(thread, SIGTERM));
}

static int
pthread_join(sp_pthread_t thread, void **value __unused)
{
	int status;

	waitpid(thread, &status, 0);
	return (status);
}
#endif


static pam_handle_t *sshpam_handle;
static int sshpam_err;
static int sshpam_authenticated;
static int sshpam_new_authtok_reqd;
static int sshpam_session_open;
static int sshpam_cred_established;

struct pam_ctxt {
	sp_pthread_t	 pam_thread;
	int		 pam_psock;
	int		 pam_csock;
	int		 pam_done;
};

static void sshpam_free_ctx(void *);

/*
 * Conversation function for authentication thread.
 */
static int
sshpam_thread_conv(int n, const struct pam_message **msg,
    struct pam_response **resp, void *data)
{
	Buffer buffer;
	struct pam_ctxt *ctxt;
	int i;

	ctxt = data;
	if (n <= 0 || n > PAM_MAX_NUM_MSG)
		return (PAM_CONV_ERR);
	*resp = xmalloc(n * sizeof **resp);
	buffer_init(&buffer);
	for (i = 0; i < n; ++i) {
		resp[i]->resp_retcode = 0;
		resp[i]->resp = NULL;
		switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
		case PAM_PROMPT_ECHO_OFF:
			buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
			ssh_msg_send(ctxt->pam_csock, 
			    PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
			ssh_msg_recv(ctxt->pam_csock, &buffer);
			if (buffer_get_char(&buffer) != PAM_AUTHTOK)
				goto fail;
			resp[i]->resp = buffer_get_string(&buffer, NULL);
			break;
		case PAM_PROMPT_ECHO_ON:
			buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
			ssh_msg_send(ctxt->pam_csock, 
			    PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
			ssh_msg_recv(ctxt->pam_csock, &buffer);
			if (buffer_get_char(&buffer) != PAM_AUTHTOK)
				goto fail;
			resp[i]->resp = buffer_get_string(&buffer, NULL);
			break;
		case PAM_ERROR_MSG:
			buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
			ssh_msg_send(ctxt->pam_csock, 
			    PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
			break;
		case PAM_TEXT_INFO:
			buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
			ssh_msg_send(ctxt->pam_csock, 
			    PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
			break;
		default:
			goto fail;
		}
		buffer_clear(&buffer);
	}
	buffer_free(&buffer);
	return (PAM_SUCCESS);
 fail:
	while (i)
		xfree(resp[--i]);
	xfree(*resp);
	*resp = NULL;
	buffer_free(&buffer);
	return (PAM_CONV_ERR);
}

/*
 * Authentication thread.
 */
static void *
sshpam_thread(void *ctxtp)
{
	struct pam_ctxt *ctxt = ctxtp;
	Buffer buffer;
	struct pam_conv sshpam_conv;
#ifndef USE_POSIX_THREADS
	const char *pam_user;

	pam_get_item(sshpam_handle, PAM_USER, (const void **)&pam_user);
	setproctitle("%s [pam]", pam_user);
#endif

	sshpam_conv.conv = sshpam_thread_conv;
	sshpam_conv.appdata_ptr = ctxt;

	buffer_init(&buffer);
	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
	    (const void *)&sshpam_conv);
	if (sshpam_err != PAM_SUCCESS)
		goto auth_fail;
	sshpam_err = pam_authenticate(sshpam_handle, 0);
	if (sshpam_err != PAM_SUCCESS)
		goto auth_fail;
	buffer_put_cstring(&buffer, "OK");
	ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer);
	buffer_free(&buffer);
	pthread_exit(NULL);

 auth_fail:
	buffer_put_cstring(&buffer,
	    pam_strerror(sshpam_handle, sshpam_err));
	ssh_msg_send(ctxt->pam_csock, PAM_AUTH_ERR, &buffer);
	buffer_free(&buffer);
	pthread_exit(NULL);
	
	return (NULL); /* Avoid warning for non-pthread case */
}

static void
sshpam_thread_cleanup(void *ctxtp)
{
	struct pam_ctxt *ctxt = ctxtp;

	pthread_cancel(ctxt->pam_thread);
	pthread_join(ctxt->pam_thread, NULL);
	close(ctxt->pam_psock);
	close(ctxt->pam_csock);
}

static int
sshpam_null_conv(int n, const struct pam_message **msg,
    struct pam_response **resp, void *data)
{
	return (PAM_CONV_ERR);
}

static struct pam_conv null_conv = { sshpam_null_conv, NULL };

static void
sshpam_cleanup(void *arg)
{
	(void)arg;
	debug("PAM: cleanup");
	pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv);
	if (sshpam_cred_established) {
		pam_setcred(sshpam_handle, PAM_DELETE_CRED);
		sshpam_cred_established = 0;
	}
	if (sshpam_session_open) {
		pam_close_session(sshpam_handle, PAM_SILENT);
		sshpam_session_open = 0;
	}
	sshpam_authenticated = sshpam_new_authtok_reqd = 0;
	pam_end(sshpam_handle, sshpam_err);
	sshpam_handle = NULL;
}

static int
sshpam_init(const char *user)
{
	extern u_int utmp_len;
	const char *pam_rhost, *pam_user;

	if (sshpam_handle != NULL) {
		/* We already have a PAM context; check if the user matches */
		sshpam_err = pam_get_item(sshpam_handle,
		    PAM_USER, (const void **)&pam_user);
		if (sshpam_err == PAM_SUCCESS && strcmp(user, pam_user) == 0)
			return (0);
		fatal_remove_cleanup(sshpam_cleanup, NULL);
		pam_end(sshpam_handle, sshpam_err);
		sshpam_handle = NULL;
	}
	debug("PAM: initializing for \"%s\"", user);
	sshpam_err = pam_start("sshd", user, &null_conv, &sshpam_handle);
	if (sshpam_err != PAM_SUCCESS) {
		pam_end(sshpam_handle, sshpam_err);
		sshpam_handle = NULL;
		return (-1);
	}
	pam_rhost = get_remote_name_or_ip(utmp_len, options.use_dns);
	debug("PAM: setting PAM_RHOST to \"%s\"", pam_rhost);
	sshpam_err = pam_set_item(sshpam_handle, PAM_RHOST, pam_rhost);
	if (sshpam_err != PAM_SUCCESS) {
		pam_end(sshpam_handle, sshpam_err);
		sshpam_handle = NULL;
		return (-1);
	}
#ifdef PAM_TTY_KLUDGE
        /*
         * Some silly PAM modules (e.g. pam_time) require a TTY to operate.
         * sshd doesn't set the tty until too late in the auth process and 
	 * may not even set one (for tty-less connections)
         */
	debug("PAM: setting PAM_TTY to \"ssh\"");
	sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, "ssh");
	if (sshpam_err != PAM_SUCCESS) {
		pam_end(sshpam_handle, sshpam_err);
		sshpam_handle = NULL;
		return (-1);
	}
#endif
	fatal_add_cleanup(sshpam_cleanup, NULL);
	return (0);
}

static void *
sshpam_init_ctx(Authctxt *authctxt)
{
	struct pam_ctxt *ctxt;
	int socks[2];

	/* Refuse to start if we don't have PAM enabled */
	if (!options.use_pam)
		return NULL;

	/* Initialize PAM */
	if (sshpam_init(authctxt->user) == -1) {
		error("PAM: initialization failed");
		return (NULL);
	}

	ctxt = xmalloc(sizeof *ctxt);
	ctxt->pam_done = 0;

	/* Start the authentication thread */
	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, socks) == -1) {
		error("PAM: failed create sockets: %s", strerror(errno));
		xfree(ctxt);
		return (NULL);
	}
	ctxt->pam_psock = socks[0];
	ctxt->pam_csock = socks[1];
	if (pthread_create(&ctxt->pam_thread, NULL, sshpam_thread, ctxt) == -1) {
		error("PAM: failed to start authentication thread: %s",
		    strerror(errno));
		close(socks[0]);
		close(socks[1]);
		xfree(ctxt);
		return (NULL);
	}
	fatal_add_cleanup(sshpam_thread_cleanup, ctxt);
	return (ctxt);
}

static int
sshpam_query(void *ctx, char **name, char **info,
    u_int *num, char ***prompts, u_int **echo_on)
{
	Buffer buffer;
	struct pam_ctxt *ctxt = ctx;
	size_t plen;
	u_char type;
	char *msg;
	size_t len;

	buffer_init(&buffer);
	*name = xstrdup("");
	*info = xstrdup("");
	*prompts = xmalloc(sizeof(char *));
	**prompts = NULL;
	plen = 0;
	*echo_on = xmalloc(sizeof(u_int));
	while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) {
		type = buffer_get_char(&buffer);
		msg = buffer_get_string(&buffer, NULL);
		switch (type) {
		case PAM_PROMPT_ECHO_ON:
		case PAM_PROMPT_ECHO_OFF:
			*num = 1;
			len = plen + strlen(msg) + 1;
			**prompts = xrealloc(**prompts, len);
			plen += snprintf(**prompts + plen, len, "%s", msg);
			**echo_on = (type == PAM_PROMPT_ECHO_ON);
			xfree(msg);
			return (0);
		case PAM_ERROR_MSG:
		case PAM_TEXT_INFO:
			/* accumulate messages */
			len = plen + strlen(msg) + 1;
			**prompts = xrealloc(**prompts, len);
			plen += snprintf(**prompts + plen, len, "%s", msg);
			xfree(msg);
			break;
		case PAM_SUCCESS:
		case PAM_AUTH_ERR:
			if (**prompts != NULL) {
				/* drain any accumulated messages */
#if 0 /* XXX - not compatible with privsep */
				packet_start(SSH2_MSG_USERAUTH_BANNER);
				packet_put_cstring(**prompts);
				packet_put_cstring("");
				packet_send();
				packet_write_wait();
#endif
				xfree(**prompts);
				**prompts = NULL;
			}
			if (type == PAM_SUCCESS) {
				*num = 0;
				**echo_on = 0;
				ctxt->pam_done = 1;
				xfree(msg);
				return (0);
			}
			error("PAM: %s", msg);
		default:
			*num = 0;
			**echo_on = 0;
			xfree(msg);
			ctxt->pam_done = -1;
			return (-1);
		}
	}
	return (-1);
}

/* XXX - see also comment in auth-chall.c:verify_response */
static int
sshpam_respond(void *ctx, u_int num, char **resp)
{
	Buffer buffer;
	struct pam_ctxt *ctxt = ctx;

	debug2("PAM: %s", __func__);
	switch (ctxt->pam_done) {
	case 1:
		sshpam_authenticated = 1;
		return (0);
	case 0:
		break;
	default:
		return (-1);
	}
	if (num != 1) {
		error("PAM: expected one response, got %u", num);
		return (-1);
	}
	buffer_init(&buffer);
	buffer_put_cstring(&buffer, *resp);
	ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer);
	buffer_free(&buffer);
	return (1);
}

static void
sshpam_free_ctx(void *ctxtp)
{
	struct pam_ctxt *ctxt = ctxtp;

	fatal_remove_cleanup(sshpam_thread_cleanup, ctxt);
	sshpam_thread_cleanup(ctxtp);
	xfree(ctxt);
	/*
	 * We don't call sshpam_cleanup() here because we may need the PAM
	 * handle at a later stage, e.g. when setting up a session.  It's
	 * still on the cleanup list, so pam_end() *will* be called before
	 * the server process terminates.
	 */
}

KbdintDevice sshpam_device = {
	"pam",
	sshpam_init_ctx,
	sshpam_query,
	sshpam_respond,
	sshpam_free_ctx
};

KbdintDevice mm_sshpam_device = {
	"pam",
	mm_sshpam_init_ctx,
	mm_sshpam_query,
	mm_sshpam_respond,
	mm_sshpam_free_ctx
};

/*
 * This replaces auth-pam.c
 */
void
start_pam(const char *user)
{
	if (!options.use_pam)
		fatal("PAM: initialisation requested when UsePAM=no");

	if (sshpam_init(user) == -1)
		fatal("PAM: initialisation failed");
}

void
finish_pam(void)
{
	fatal_remove_cleanup(sshpam_cleanup, NULL);
	sshpam_cleanup(NULL);
}

u_int
do_pam_account(void)
{
	sshpam_err = pam_acct_mgmt(sshpam_handle, 0);
	debug3("%s: pam_acct_mgmt = %d", __func__, sshpam_err);
	
	if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD)
		return (0);

	if (sshpam_err == PAM_NEW_AUTHTOK_REQD) {
		sshpam_new_authtok_reqd = 1;

		/* Prevent forwardings until password changed */
		no_port_forwarding_flag |= 2;
		no_agent_forwarding_flag |= 2;
		no_x11_forwarding_flag |= 2;
	}

	return (1);
}

void
do_pam_session(const char *user, const char *tty)
{
	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV, 
	    (const void *)&null_conv);
	if (sshpam_err != PAM_SUCCESS)
		fatal("PAM: failed to set PAM_CONV: %s",
		    pam_strerror(sshpam_handle, sshpam_err));
	if (tty != NULL) {
		debug("PAM: setting PAM_TTY to \"%s\"", tty);
		sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, tty);
		if (sshpam_err != PAM_SUCCESS)
			fatal("PAM: failed to set PAM_TTY: %s",
			    pam_strerror(sshpam_handle, sshpam_err));
	}
	sshpam_err = pam_open_session(sshpam_handle, 0);
	if (sshpam_err != PAM_SUCCESS)
		fatal("PAM: pam_open_session(): %s",
		    pam_strerror(sshpam_handle, sshpam_err));
	sshpam_session_open = 1;
}

void
do_pam_setcred(int init)
{
	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
	    (const void *)&null_conv);
	if (sshpam_err != PAM_SUCCESS)
		fatal("PAM: failed to set PAM_CONV: %s",
		    pam_strerror(sshpam_handle, sshpam_err));
	if (init) {
		debug("PAM: establishing credentials");
		sshpam_err = pam_setcred(sshpam_handle, PAM_ESTABLISH_CRED);
	} else {
		debug("PAM: reinitializing credentials");
		sshpam_err = pam_setcred(sshpam_handle, PAM_REINITIALIZE_CRED);
	}
	if (sshpam_err == PAM_SUCCESS) {
		sshpam_cred_established = 1;
		return;
	}
	if (sshpam_authenticated)
		fatal("PAM: pam_setcred(): %s",
		    pam_strerror(sshpam_handle, sshpam_err));
	else
		debug("PAM: pam_setcred(): %s",
		    pam_strerror(sshpam_handle, sshpam_err));
}

int
is_pam_password_change_required(void)
{
	return (sshpam_new_authtok_reqd);
}

static int
pam_chauthtok_conv(int n, const struct pam_message **msg,
    struct pam_response **resp, void *data)
{
	char input[PAM_MAX_MSG_SIZE];
	int i;

	if (n <= 0 || n > PAM_MAX_NUM_MSG)
		return (PAM_CONV_ERR);
	*resp = xmalloc(n * sizeof **resp);
	for (i = 0; i < n; ++i) {
		switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
		case PAM_PROMPT_ECHO_OFF:
			resp[i]->resp =
			    read_passphrase(PAM_MSG_MEMBER(msg, i, msg), 
			    RP_ALLOW_STDIN);
			resp[i]->resp_retcode = PAM_SUCCESS;
			break;
		case PAM_PROMPT_ECHO_ON:
			fputs(PAM_MSG_MEMBER(msg, i, msg), stderr);
			fgets(input, sizeof input, stdin);
			resp[i]->resp = xstrdup(input);
			resp[i]->resp_retcode = PAM_SUCCESS;
			break;
		case PAM_ERROR_MSG:
		case PAM_TEXT_INFO:
			fputs(PAM_MSG_MEMBER(msg, i, msg), stderr);
			resp[i]->resp_retcode = PAM_SUCCESS;
			break;
		default:
			goto fail;
		}
	}
	return (PAM_SUCCESS);
 fail:
	while (i)
		xfree(resp[--i]);
	xfree(*resp);
	*resp = NULL;
	return (PAM_CONV_ERR);
}

/*
 * XXX this should be done in the authentication phase, but ssh1 doesn't
 * support that
 */
void
do_pam_chauthtok(void)
{
	struct pam_conv pam_conv;

	pam_conv.conv = pam_chauthtok_conv;
	pam_conv.appdata_ptr = NULL;

	if (use_privsep)
		fatal("Password expired (unable to change with privsep)");
	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
	    (const void *)&pam_conv);
	if (sshpam_err != PAM_SUCCESS)
		fatal("PAM: failed to set PAM_CONV: %s",
		    pam_strerror(sshpam_handle, sshpam_err));
	debug("PAM: changing password");
	sshpam_err = pam_chauthtok(sshpam_handle, PAM_CHANGE_EXPIRED_AUTHTOK);
	if (sshpam_err != PAM_SUCCESS)
		fatal("PAM: pam_chauthtok(): %s",
		    pam_strerror(sshpam_handle, sshpam_err));
}

/* 
 * Set a PAM environment string. We need to do this so that the session
 * modules can handle things like Kerberos/GSI credentials that appear
 * during the ssh authentication process.
 */

int
do_pam_putenv(char *name, char *value) 
{
	char *compound;
	int ret = 1;

#ifdef HAVE_PAM_PUTENV	
	compound = xmalloc(strlen(name)+strlen(value)+2);
	if (compound) {
		sprintf(compound,"%s=%s",name,value);
		ret = pam_putenv(sshpam_handle,compound);
		xfree(compound);
	}
#endif
	return (ret);
}

void
print_pam_messages(void)
{
	/* XXX */
}

char **
fetch_pam_environment(void)
{
#ifdef HAVE_PAM_GETENVLIST
	debug("PAM: retrieving environment");
	return (pam_getenvlist(sshpam_handle));
#else
	return (NULL);
#endif
}

void
free_pam_environment(char **env)
{
	char **envp;

	if (env == NULL)
		return;

	for (envp = env; *envp; envp++)
		xfree(*envp);
	xfree(env);
}

#endif /* USE_PAM */
Commit	Line	Data
05114c74	1	/*-
	2	* Copyright (c) 2002 Networks Associates Technology, Inc.
	3	* All rights reserved.
	4	*
	5	* This software was developed for the FreeBSD Project by ThinkSec AS and
	6	* NAI Labs, the Security Research Division of Network Associates, Inc.
	7	* under DARPA/SPAWAR contract N66001-01-C-8035 ("CBOSS"), as part of the
	8	* DARPA CHATS research program.
09564242	9	*
	10	* Redistribution and use in source and binary forms, with or without
	11	* modification, are permitted provided that the following conditions
	12	* are met:
	13	* 1. Redistributions of source code must retain the above copyright
	14	* notice, this list of conditions and the following disclaimer.
	15	* 2. Redistributions in binary form must reproduce the above copyright
	16	* notice, this list of conditions and the following disclaimer in the
	17	* documentation and/or other materials provided with the distribution.
09564242	18	*
05114c74	19	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR AND CONTRIBUTORS ``AS IS'' AND
	20	* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
	21	* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
	22	* ARE DISCLAIMED. IN NO EVENT SHALL THE AUTHOR OR CONTRIBUTORS BE LIABLE
	23	* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
	24	* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
	25	* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
	26	* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
	27	* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
	28	* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
	29	* SUCH DAMAGE.
a5c9cd31	30	*/
a5c9cd31	31
5ff453c0	32	/* Based on $FreeBSD: src/crypto/openssh/auth2-pam-freebsd.c,v 1.11 2003/03/31 13:48:18 des Exp $ */
a5c9cd31	33	#include "includes.h"
5ff453c0	34	RCSID("$Id$");
a5c9cd31	35
a5c9cd31	36	#ifdef USE_PAM
05114c74	37	#include <security/pam_appl.h>
05114c74	38
fde58bd4	39	#include "auth.h"
5c377b3b	40	#include "auth-pam.h"
05114c74	41	#include "buffer.h"
05114c74	42	#include "bufaux.h"
42f11eb2	43	#include "canohost.h"
05114c74	44	#include "log.h"
	45	#include "monitor_wrap.h"
	46	#include "msg.h"
	47	#include "packet.h"
42f11eb2	48	#include "readpass.h"
05114c74	49	#include "servconf.h"
	50	#include "ssh2.h"
	51	#include "xmalloc.h"
5b9e2464	52	#include "auth-options.h"
a5c9cd31	53
7fceb20d	54	extern ServerOptions options;
7fceb20d	55
05114c74	56	#define __unused
277f55cf	57
05114c74	58	#ifdef USE_POSIX_THREADS
	59	#include <pthread.h>
	60	/*
	61	* Avoid namespace clash when not using pthreads for systems with
	62	* pthreads, which unconditionally define pthread_t via sys/types.h
	63	* (e.g. Linux)
	64	*/
	65	typedef pthread_t sp_pthread_t;
	66	#else
	67	/*
	68	* Simulate threads with processes.
	69	*/
	70	typedef pid_t sp_pthread_t;
a5c9cd31	71
05114c74	72	static void
	73	pthread_exit(void *value __unused)
	74	{
	75	_exit(0);
	76	}
5daf7064	77
05114c74	78	static int
	79	pthread_create(sp_pthread_t thread, const void attr __unused,
	80	void (thread_start)(void ), void arg)
	81	{
	82	pid_t pid;
	83
	84	switch ((pid = fork())) {
	85	case -1:
	86	error("fork(): %s", strerror(errno));
	87	return (-1);
	88	case 0:
	89	thread_start(arg);
	90	_exit(1);
	91	default:
	92	*thread = pid;
	93	return (0);
	94	}
	95	}
a5c9cd31	96
05114c74	97	static int
05114c74	98	pthread_cancel(sp_pthread_t thread)
8c9fe09e	99	{
05114c74	100	return (kill(thread, SIGTERM));
8c9fe09e	101	}
8c9fe09e	102
05114c74	103	static int
05114c74	104	pthread_join(sp_pthread_t thread, void **value __unused)
8c9fe09e	105	{
05114c74	106	int status;
	107
	108	waitpid(thread, &status, 0);
	109	return (status);
8c9fe09e	110	}
05114c74	111	#endif
	112
	113
	114	static pam_handle_t *sshpam_handle;
	115	static int sshpam_err;
	116	static int sshpam_authenticated;
	117	static int sshpam_new_authtok_reqd;
	118	static int sshpam_session_open;
	119	static int sshpam_cred_established;
	120
	121	struct pam_ctxt {
	122	sp_pthread_t pam_thread;
	123	int pam_psock;
	124	int pam_csock;
	125	int pam_done;
	126	};
	127
	128	static void sshpam_free_ctx(void *);
ad55cd03	129
ad55cd03	130	/*
05114c74	131	* Conversation function for authentication thread.
ad55cd03	132	*/
05114c74	133	static int
5b9e2464	134	sshpam_thread_conv(int n, const struct pam_message **msg,
5b9e2464	135	struct pam_response *resp, void data)
a5c9cd31	136	{
05114c74	137	Buffer buffer;
	138	struct pam_ctxt *ctxt;
	139	int i;
	140
	141	ctxt = data;
	142	if (n <= 0 \|\| n > PAM_MAX_NUM_MSG)
	143	return (PAM_CONV_ERR);
	144	resp = xmalloc(n sizeof **resp);
	145	buffer_init(&buffer);
	146	for (i = 0; i < n; ++i) {
	147	resp[i]->resp_retcode = 0;
	148	resp[i]->resp = NULL;
	149	switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
	150	case PAM_PROMPT_ECHO_OFF:
	151	buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
	152	ssh_msg_send(ctxt->pam_csock,
	153	PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
	154	ssh_msg_recv(ctxt->pam_csock, &buffer);
	155	if (buffer_get_char(&buffer) != PAM_AUTHTOK)
	156	goto fail;
	157	resp[i]->resp = buffer_get_string(&buffer, NULL);
	158	break;
	159	case PAM_PROMPT_ECHO_ON:
	160	buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
	161	ssh_msg_send(ctxt->pam_csock,
	162	PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
	163	ssh_msg_recv(ctxt->pam_csock, &buffer);
	164	if (buffer_get_char(&buffer) != PAM_AUTHTOK)
	165	goto fail;
	166	resp[i]->resp = buffer_get_string(&buffer, NULL);
	167	break;
	168	case PAM_ERROR_MSG:
	169	buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
	170	ssh_msg_send(ctxt->pam_csock,
	171	PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
	172	break;
	173	case PAM_TEXT_INFO:
	174	buffer_put_cstring(&buffer, PAM_MSG_MEMBER(msg, i, msg));
	175	ssh_msg_send(ctxt->pam_csock,
	176	PAM_MSG_MEMBER(msg, i, msg_style), &buffer);
	177	break;
	178	default:
	179	goto fail;
a5c9cd31	180	}
05114c74	181	buffer_clear(&buffer);
a5c9cd31	182	}
05114c74	183	buffer_free(&buffer);
	184	return (PAM_SUCCESS);
	185	fail:
	186	while (i)
	187	xfree(resp[--i]);
	188	xfree(*resp);
	189	*resp = NULL;
	190	buffer_free(&buffer);
	191	return (PAM_CONV_ERR);
	192	}
a5c9cd31	193
05114c74	194	/*
	195	* Authentication thread.
	196	*/
	197	static void *
	198	sshpam_thread(void *ctxtp)
	199	{
	200	struct pam_ctxt *ctxt = ctxtp;
	201	Buffer buffer;
c53917a9	202	struct pam_conv sshpam_conv;
05114c74	203	#ifndef USE_POSIX_THREADS
	204	const char *pam_user;
	205
	206	pam_get_item(sshpam_handle, PAM_USER, (const void **)&pam_user);
	207	setproctitle("%s [pam]", pam_user);
	208	#endif
a5c9cd31	209
c53917a9	210	sshpam_conv.conv = sshpam_thread_conv;
	211	sshpam_conv.appdata_ptr = ctxt;
	212
05114c74	213	buffer_init(&buffer);
	214	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
	215	(const void *)&sshpam_conv);
	216	if (sshpam_err != PAM_SUCCESS)
	217	goto auth_fail;
	218	sshpam_err = pam_authenticate(sshpam_handle, 0);
	219	if (sshpam_err != PAM_SUCCESS)
	220	goto auth_fail;
05114c74	221	buffer_put_cstring(&buffer, "OK");
	222	ssh_msg_send(ctxt->pam_csock, sshpam_err, &buffer);
	223	buffer_free(&buffer);
	224	pthread_exit(NULL);
	225
	226	auth_fail:
	227	buffer_put_cstring(&buffer,
	228	pam_strerror(sshpam_handle, sshpam_err));
	229	ssh_msg_send(ctxt->pam_csock, PAM_AUTH_ERR, &buffer);
	230	buffer_free(&buffer);
	231	pthread_exit(NULL);
	232
	233	return (NULL); /* Avoid warning for non-pthread case */
a5c9cd31	234	}
a5c9cd31	235
05114c74	236	static void
05114c74	237	sshpam_thread_cleanup(void *ctxtp)
a5c9cd31	238	{
05114c74	239	struct pam_ctxt *ctxt = ctxtp;
a5c9cd31	240
05114c74	241	pthread_cancel(ctxt->pam_thread);
	242	pthread_join(ctxt->pam_thread, NULL);
	243	close(ctxt->pam_psock);
	244	close(ctxt->pam_csock);
	245	}
a5c9cd31	246
05114c74	247	static int
5b9e2464	248	sshpam_null_conv(int n, const struct pam_message **msg,
5b9e2464	249	struct pam_response *resp, void data)
05114c74	250	{
05114c74	251	return (PAM_CONV_ERR);
05114c74	252	}
a5c9cd31	253
05114c74	254	static struct pam_conv null_conv = { sshpam_null_conv, NULL };
	255
	256	static void
	257	sshpam_cleanup(void *arg)
	258	{
	259	(void)arg;
	260	debug("PAM: cleanup");
	261	pam_set_item(sshpam_handle, PAM_CONV, (const void *)&null_conv);
	262	if (sshpam_cred_established) {
	263	pam_setcred(sshpam_handle, PAM_DELETE_CRED);
	264	sshpam_cred_established = 0;
	265	}
	266	if (sshpam_session_open) {
	267	pam_close_session(sshpam_handle, PAM_SILENT);
	268	sshpam_session_open = 0;
a5c9cd31	269	}
05114c74	270	sshpam_authenticated = sshpam_new_authtok_reqd = 0;
	271	pam_end(sshpam_handle, sshpam_err);
	272	sshpam_handle = NULL;
a5c9cd31	273	}
a5c9cd31	274
05114c74	275	static int
05114c74	276	sshpam_init(const char *user)
a5c9cd31	277	{
05114c74	278	extern u_int utmp_len;
	279	const char pam_rhost, pam_user;
	280
	281	if (sshpam_handle != NULL) {
	282	/* We already have a PAM context; check if the user matches */
	283	sshpam_err = pam_get_item(sshpam_handle,
	284	PAM_USER, (const void **)&pam_user);
	285	if (sshpam_err == PAM_SUCCESS && strcmp(user, pam_user) == 0)
	286	return (0);
	287	fatal_remove_cleanup(sshpam_cleanup, NULL);
	288	pam_end(sshpam_handle, sshpam_err);
	289	sshpam_handle = NULL;
	290	}
	291	debug("PAM: initializing for \"%s\"", user);
	292	sshpam_err = pam_start("sshd", user, &null_conv, &sshpam_handle);
5ff453c0	293	if (sshpam_err != PAM_SUCCESS) {
	294	pam_end(sshpam_handle, sshpam_err);
	295	sshpam_handle = NULL;
05114c74	296	return (-1);
5ff453c0	297	}
c5a7d788	298	pam_rhost = get_remote_name_or_ip(utmp_len, options.use_dns);
05d62329	299	debug("PAM: setting PAM_RHOST to \"%s\"", pam_rhost);
05114c74	300	sshpam_err = pam_set_item(sshpam_handle, PAM_RHOST, pam_rhost);
5ff453c0	301	if (sshpam_err != PAM_SUCCESS) {
5b9e2464	302	pam_end(sshpam_handle, sshpam_err);
5ff453c0	303	sshpam_handle = NULL;
	304	return (-1);
	305	}
	306	#ifdef PAM_TTY_KLUDGE
	307	/*
	308	* Some silly PAM modules (e.g. pam_time) require a TTY to operate.
	309	* sshd doesn't set the tty until too late in the auth process and
	310	* may not even set one (for tty-less connections)
	311	*/
	312	debug("PAM: setting PAM_TTY to \"ssh\"");
	313	sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, "ssh");
05114c74	314	if (sshpam_err != PAM_SUCCESS) {
	315	pam_end(sshpam_handle, sshpam_err);
	316	sshpam_handle = NULL;
	317	return (-1);
a5c9cd31	318	}
5ff453c0	319	#endif
05114c74	320	fatal_add_cleanup(sshpam_cleanup, NULL);
05114c74	321	return (0);
a5c9cd31	322	}
a5c9cd31	323
05114c74	324	static void *
05114c74	325	sshpam_init_ctx(Authctxt *authctxt)
a5c9cd31	326	{
05114c74	327	struct pam_ctxt *ctxt;
05114c74	328	int socks[2];
2b87da3b	329
7fceb20d	330	/* Refuse to start if we don't have PAM enabled */
	331	if (!options.use_pam)
	332	return NULL;
	333
05114c74	334	/* Initialize PAM */
	335	if (sshpam_init(authctxt->user) == -1) {
	336	error("PAM: initialization failed");
	337	return (NULL);
	338	}
5c377b3b	339
05114c74	340	ctxt = xmalloc(sizeof *ctxt);
	341	ctxt->pam_done = 0;
	342
	343	/* Start the authentication thread */
	344	if (socketpair(AF_UNIX, SOCK_STREAM, PF_UNSPEC, socks) == -1) {
	345	error("PAM: failed create sockets: %s", strerror(errno));
	346	xfree(ctxt);
	347	return (NULL);
	348	}
	349	ctxt->pam_psock = socks[0];
	350	ctxt->pam_csock = socks[1];
	351	if (pthread_create(&ctxt->pam_thread, NULL, sshpam_thread, ctxt) == -1) {
	352	error("PAM: failed to start authentication thread: %s",
	353	strerror(errno));
	354	close(socks[0]);
	355	close(socks[1]);
	356	xfree(ctxt);
	357	return (NULL);
a5c9cd31	358	}
05114c74	359	fatal_add_cleanup(sshpam_thread_cleanup, ctxt);
	360	return (ctxt);
	361	}
a5c9cd31	362
05114c74	363	static int
	364	sshpam_query(void ctx, char name, char *info,
	365	u_int num, char prompts, u_int echo_on)
	366	{
	367	Buffer buffer;
	368	struct pam_ctxt *ctxt = ctx;
	369	size_t plen;
	370	u_char type;
	371	char *msg;
cbdeccf3	372	size_t len;
05114c74	373
	374	buffer_init(&buffer);
	375	*name = xstrdup("");
	376	*info = xstrdup("");
	377	prompts = xmalloc(sizeof(char ));
	378	**prompts = NULL;
	379	plen = 0;
	380	*echo_on = xmalloc(sizeof(u_int));
	381	while (ssh_msg_recv(ctxt->pam_psock, &buffer) == 0) {
	382	type = buffer_get_char(&buffer);
	383	msg = buffer_get_string(&buffer, NULL);
	384	switch (type) {
	385	case PAM_PROMPT_ECHO_ON:
	386	case PAM_PROMPT_ECHO_OFF:
	387	*num = 1;
cbdeccf3	388	len = plen + strlen(msg) + 1;
	389	prompts = xrealloc(prompts, len);
	390	plen += snprintf(**prompts + plen, len, "%s", msg);
05114c74	391	**echo_on = (type == PAM_PROMPT_ECHO_ON);
	392	xfree(msg);
	393	return (0);
	394	case PAM_ERROR_MSG:
	395	case PAM_TEXT_INFO:
	396	/* accumulate messages */
cbdeccf3	397	len = plen + strlen(msg) + 1;
	398	prompts = xrealloc(prompts, len);
	399	plen += snprintf(**prompts + plen, len, "%s", msg);
05114c74	400	xfree(msg);
5daf7064	401	break;
05114c74	402	case PAM_SUCCESS:
	403	case PAM_AUTH_ERR:
	404	if (**prompts != NULL) {
	405	/* drain any accumulated messages */
	406	#if 0 /* XXX - not compatible with privsep */
	407	packet_start(SSH2_MSG_USERAUTH_BANNER);
	408	packet_put_cstring(**prompts);
	409	packet_put_cstring("");
	410	packet_send();
	411	packet_write_wait();
e108cd93	412	#endif
05114c74	413	xfree(**prompts);
	414	**prompts = NULL;
	415	}
	416	if (type == PAM_SUCCESS) {
	417	*num = 0;
	418	**echo_on = 0;
	419	ctxt->pam_done = 1;
	420	xfree(msg);
	421	return (0);
	422	}
	423	error("PAM: %s", msg);
5daf7064	424	default:
05114c74	425	*num = 0;
	426	**echo_on = 0;
	427	xfree(msg);
	428	ctxt->pam_done = -1;
	429	return (-1);
	430	}
a5c9cd31	431	}
05114c74	432	return (-1);
a5c9cd31	433	}
a5c9cd31	434
05114c74	435	/* XXX - see also comment in auth-chall.c:verify_response */
	436	static int
	437	sshpam_respond(void ctx, u_int num, char *resp)
a5c9cd31	438	{
05114c74	439	Buffer buffer;
	440	struct pam_ctxt *ctxt = ctx;
	441
	442	debug2("PAM: %s", __func__);
	443	switch (ctxt->pam_done) {
	444	case 1:
	445	sshpam_authenticated = 1;
	446	return (0);
	447	case 0:
	448	break;
	449	default:
	450	return (-1);
a5c9cd31	451	}
05114c74	452	if (num != 1) {
	453	error("PAM: expected one response, got %u", num);
	454	return (-1);
	455	}
	456	buffer_init(&buffer);
	457	buffer_put_cstring(&buffer, *resp);
	458	ssh_msg_send(ctxt->pam_psock, PAM_AUTHTOK, &buffer);
	459	buffer_free(&buffer);
	460	return (1);
a5c9cd31	461	}
a5c9cd31	462
05114c74	463	static void
05114c74	464	sshpam_free_ctx(void *ctxtp)
a5c9cd31	465	{
05114c74	466	struct pam_ctxt *ctxt = ctxtp;
39ce53de	467
05114c74	468	fatal_remove_cleanup(sshpam_thread_cleanup, ctxt);
	469	sshpam_thread_cleanup(ctxtp);
	470	xfree(ctxt);
	471	/*
	472	* We don't call sshpam_cleanup() here because we may need the PAM
	473	* handle at a later stage, e.g. when setting up a session. It's
	474	* still on the cleanup list, so pam_end() will be called before
	475	* the server process terminates.
	476	*/
ad55cd03	477	}
ad55cd03	478
05114c74	479	KbdintDevice sshpam_device = {
	480	"pam",
	481	sshpam_init_ctx,
	482	sshpam_query,
	483	sshpam_respond,
	484	sshpam_free_ctx
	485	};
	486
	487	KbdintDevice mm_sshpam_device = {
	488	"pam",
	489	mm_sshpam_init_ctx,
	490	mm_sshpam_query,
	491	mm_sshpam_respond,
	492	mm_sshpam_free_ctx
	493	};
2919e060	494
2b87da3b	495	/*
05114c74	496	* This replaces auth-pam.c
ad55cd03	497	*/
05114c74	498	void
05114c74	499	start_pam(const char *user)
ad55cd03	500	{
817e6d38	501	if (!options.use_pam)
	502	fatal("PAM: initialisation requested when UsePAM=no");
	503
05114c74	504	if (sshpam_init(user) == -1)
05114c74	505	fatal("PAM: initialisation failed");
a5c9cd31	506	}
a5c9cd31	507
05114c74	508	void
05114c74	509	finish_pam(void)
a5c9cd31	510	{
05114c74	511	fatal_remove_cleanup(sshpam_cleanup, NULL);
05114c74	512	sshpam_cleanup(NULL);
a5c9cd31	513	}
a5c9cd31	514
5b9e2464	515	u_int
5b9e2464	516	do_pam_account(void)
a5c9cd31	517	{
5b9e2464	518	sshpam_err = pam_acct_mgmt(sshpam_handle, 0);
	519	debug3("%s: pam_acct_mgmt = %d", __func__, sshpam_err);
	520
	521	if (sshpam_err != PAM_SUCCESS && sshpam_err != PAM_NEW_AUTHTOK_REQD)
	522	return (0);
	523
	524	if (sshpam_err == PAM_NEW_AUTHTOK_REQD) {
	525	sshpam_new_authtok_reqd = 1;
	526
	527	/* Prevent forwardings until password changed */
	528	no_port_forwarding_flag \|= 2;
	529	no_agent_forwarding_flag \|= 2;
	530	no_x11_forwarding_flag \|= 2;
	531	}
	532
05114c74	533	return (1);
05114c74	534	}
46c76c63	535
05114c74	536	void
	537	do_pam_session(const char user, const char tty)
	538	{
	539	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
	540	(const void *)&null_conv);
	541	if (sshpam_err != PAM_SUCCESS)
	542	fatal("PAM: failed to set PAM_CONV: %s",
	543	pam_strerror(sshpam_handle, sshpam_err));
26b3608b	544	if (tty != NULL) {
	545	debug("PAM: setting PAM_TTY to \"%s\"", tty);
	546	sshpam_err = pam_set_item(sshpam_handle, PAM_TTY, tty);
	547	if (sshpam_err != PAM_SUCCESS)
	548	fatal("PAM: failed to set PAM_TTY: %s",
	549	pam_strerror(sshpam_handle, sshpam_err));
	550	}
05114c74	551	sshpam_err = pam_open_session(sshpam_handle, 0);
	552	if (sshpam_err != PAM_SUCCESS)
	553	fatal("PAM: pam_open_session(): %s",
	554	pam_strerror(sshpam_handle, sshpam_err));
	555	sshpam_session_open = 1;
	556	}
cbd7492e	557
05114c74	558	void
	559	do_pam_setcred(int init)
	560	{
	561	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
	562	(const void *)&null_conv);
	563	if (sshpam_err != PAM_SUCCESS)
	564	fatal("PAM: failed to set PAM_CONV: %s",
	565	pam_strerror(sshpam_handle, sshpam_err));
	566	if (init) {
	567	debug("PAM: establishing credentials");
	568	sshpam_err = pam_setcred(sshpam_handle, PAM_ESTABLISH_CRED);
	569	} else {
	570	debug("PAM: reinitializing credentials");
	571	sshpam_err = pam_setcred(sshpam_handle, PAM_REINITIALIZE_CRED);
	572	}
	573	if (sshpam_err == PAM_SUCCESS) {
	574	sshpam_cred_established = 1;
	575	return;
	576	}
	577	if (sshpam_authenticated)
	578	fatal("PAM: pam_setcred(): %s",
	579	pam_strerror(sshpam_handle, sshpam_err));
	580	else
	581	debug("PAM: pam_setcred(): %s",
	582	pam_strerror(sshpam_handle, sshpam_err));
a5c9cd31	583	}
a5c9cd31	584
05114c74	585	int
05114c74	586	is_pam_password_change_required(void)
a5c9cd31	587	{
05114c74	588	return (sshpam_new_authtok_reqd);
a5c9cd31	589	}
a5c9cd31	590
05114c74	591	static int
5b9e2464	592	pam_chauthtok_conv(int n, const struct pam_message **msg,
5b9e2464	593	struct pam_response *resp, void data)
ee48c949	594	{
05114c74	595	char input[PAM_MAX_MSG_SIZE];
ee48c949	596	int i;
ee48c949	597
05114c74	598	if (n <= 0 \|\| n > PAM_MAX_NUM_MSG)
	599	return (PAM_CONV_ERR);
	600	resp = xmalloc(n sizeof **resp);
	601	for (i = 0; i < n; ++i) {
	602	switch (PAM_MSG_MEMBER(msg, i, msg_style)) {
	603	case PAM_PROMPT_ECHO_OFF:
	604	resp[i]->resp =
	605	read_passphrase(PAM_MSG_MEMBER(msg, i, msg),
	606	RP_ALLOW_STDIN);
	607	resp[i]->resp_retcode = PAM_SUCCESS;
	608	break;
	609	case PAM_PROMPT_ECHO_ON:
	610	fputs(PAM_MSG_MEMBER(msg, i, msg), stderr);
	611	fgets(input, sizeof input, stdin);
	612	resp[i]->resp = xstrdup(input);
	613	resp[i]->resp_retcode = PAM_SUCCESS;
	614	break;
	615	case PAM_ERROR_MSG:
	616	case PAM_TEXT_INFO:
	617	fputs(PAM_MSG_MEMBER(msg, i, msg), stderr);
	618	resp[i]->resp_retcode = PAM_SUCCESS;
	619	break;
	620	default:
	621	goto fail;
	622	}
ee48c949	623	}
05114c74	624	return (PAM_SUCCESS);
	625	fail:
	626	while (i)
	627	xfree(resp[--i]);
	628	xfree(*resp);
	629	*resp = NULL;
	630	return (PAM_CONV_ERR);
ee48c949	631	}
ee48c949	632
05114c74	633	/*
	634	* XXX this should be done in the authentication phase, but ssh1 doesn't
	635	* support that
	636	*/
	637	void
	638	do_pam_chauthtok(void)
a5c9cd31	639	{
c53917a9	640	struct pam_conv pam_conv;
	641
	642	pam_conv.conv = pam_chauthtok_conv;
	643	pam_conv.appdata_ptr = NULL;
05114c74	644
05114c74	645	if (use_privsep)
5b9e2464	646	fatal("Password expired (unable to change with privsep)");
05114c74	647	sshpam_err = pam_set_item(sshpam_handle, PAM_CONV,
	648	(const void *)&pam_conv);
	649	if (sshpam_err != PAM_SUCCESS)
	650	fatal("PAM: failed to set PAM_CONV: %s",
	651	pam_strerror(sshpam_handle, sshpam_err));
	652	debug("PAM: changing password");
	653	sshpam_err = pam_chauthtok(sshpam_handle, PAM_CHANGE_EXPIRED_AUTHTOK);
	654	if (sshpam_err != PAM_SUCCESS)
	655	fatal("PAM: pam_chauthtok(): %s",
	656	pam_strerror(sshpam_handle, sshpam_err));
5daf7064	657	}
5daf7064	658
749560dd	659	/*
	660	* Set a PAM environment string. We need to do this so that the session
	661	* modules can handle things like Kerberos/GSI credentials that appear
	662	* during the ssh authentication process.
	663	*/
	664
	665	int
	666	do_pam_putenv(char name, char value)
	667	{
	668	char *compound;
	669	int ret = 1;
	670
	671	#ifdef HAVE_PAM_PUTENV
	672	compound = xmalloc(strlen(name)+strlen(value)+2);
	673	if (compound) {
	674	sprintf(compound,"%s=%s",name,value);
	675	ret = pam_putenv(sshpam_handle,compound);
	676	xfree(compound);
	677	}
	678	#endif
	679	return (ret);
	680	}
	681
05114c74	682	void
05114c74	683	print_pam_messages(void)
5daf7064	684	{
05114c74	685	/* XXX */
05114c74	686	}
2b87da3b	687
05114c74	688	char **
	689	fetch_pam_environment(void)
	690	{
	691	#ifdef HAVE_PAM_GETENVLIST
	692	debug("PAM: retrieving environment");
	693	return (pam_getenvlist(sshpam_handle));
	694	#else
	695	return (NULL);
	696	#endif
	697	}
5c377b3b	698
05114c74	699	void
	700	free_pam_environment(char **env)
	701	{
	702	char **envp;
5daf7064	703
0eb6370a	704	if (env == NULL)
	705	return;
	706
05114c74	707	for (envp = env; *envp; envp++)
	708	xfree(*envp);
	709	xfree(env);
a5c9cd31	710	}
	711
	712	#endif /* USE_PAM */