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#
#
# add_file "svr-authpam.c"
#  content [6dbb7c0181129f6871c6fbb194b5cd92d0a9d337]
#
# patch "Makefile.in"
#  from [cbca06faeb152aa4d8b47590e096d52f7fd7dfda]
#    to [597afdd77f8936704ae8e3721dd800d7e0f722bf]
#
# patch "auth.h"
#  from [42a641e0c3b3027858c3f8e8e717cca76b7eddd8]
#    to [ff1ddd99ccdd09f16eabf2e22e5384dabf33543d]
#
# patch "configure.in"
#  from [f3d9be07f83d1adafab1c522bb5459e028d6efc6]
#    to [2dab0af5acf2a9845f1c249c5c10e0fc7b8c1e2e]
#
# patch "options.h"
#  from [586757c4c005905a36d6900b1857a297c010d0e9]
#    to [64a6ffbbed9f9bdf520a8b2b33f903ae63200cf3]
#
# patch "svr-auth.c"
#  from [86f05f7a7df1de1108492ed86ba038e5a2d82eaa]
#    to [aa0862ce0910cee5bfb9c0f57d1c482c9370c225]
#
# patch "svr-runopts.c"
#  from [0dc09806e7b620e96f83e49a6c18af83ad1b887f]
#    to [d4a122f8fbe9a29b5bf8c4fa05f0a938edbeba07]
#
============================================================
--- svr-authpam.c	6dbb7c0181129f6871c6fbb194b5cd92d0a9d337
+++ svr-authpam.c	6dbb7c0181129f6871c6fbb194b5cd92d0a9d337
@@ -0,0 +1,219 @@
+/*
+ * Dropbear SSH
+ *
+ * Copyright (c) 2004 Martin Carlsson
+ * Portions (c) 2004 Matt Johnston
+ * All rights reserved.
+ *
+ * Permission is hereby granted, free of charge, to any person obtaining a copy
+ * of this software and associated documentation files (the "Software"), to deal
+ * in the Software without restriction, including without limitation the rights
+ * to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+ * copies of the Software, and to permit persons to whom the Software is
+ * furnished to do so, subject to the following conditions:
+ *
+ * The above copyright notice and this permission notice shall be included in
+ * all copies or substantial portions of the Software.
+ *
+ * THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+ * IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+ * FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+ * AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+ * LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+ * OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN THE
+ * SOFTWARE. */
+
+/* Validates a user password using PAM */
+
+#include "includes.h"
+#include "session.h"
+#include "buffer.h"
+#include "dbutil.h"
+#include "auth.h"
+
+#if defined(HAVE_SECURITY_PAM_APPL_H)
+#include <security/pam_appl.h>
+#elif defined (HAVE_PAM_PAM_APPL_H)
+#include <pam/pam_appl.h>
+#endif
+
+struct UserDataS {
+	char* user;
+	char* passwd;
+};
+
+/* PAM conversation function - for now we only handle one message */
+int
+pamConvFunc(int num_msg,
+		const struct pam_message **msg,
+		struct pam_response **respp,
+		void *appdata_ptr) {
+
+	int rc = PAM_SUCCESS;
+	struct pam_response* resp = NULL;
+	struct UserDataS* userDatap = (struct UserDataS*) appdata_ptr;
+
+	const char* message = (*msg)->msg;
+
+	TRACE(("enter pamConvFunc"));
+
+	if (num_msg != 1) {
+		/* If you're getting here - Dropbear probably can't support your pam
+		 * modules. This whole file is a bit of a hack around lack of
+		 * asynchronocity in PAM anyway */
+		dropbear_log(LOG_INFO, "pamConvFunc() called with >1 messages: not supported.");
+		return PAM_CONV_ERR;
+	}
+
+	TRACE(("msg_style is %d", (*msg)->msg_style));
+	if (message) {
+		TRACE(("message is '%s'", message));
+	} else {
+		TRACE(("null message"));
+	}
+
+	switch((*msg)->msg_style) {
+
+		case PAM_PROMPT_ECHO_OFF:
+
+			if (strcmp(message, "Password:") != 0) {
+					TRACE(("PAM_PROMPT_ECHO_OFF: unrecognized prompt"));
+					rc = PAM_CONV_ERR;
+					break;
+			}
+
+			/* This looks leaky, but the PAM module-writer docs
+			 * assure us that the caller will free it... */
+			resp = (struct pam_response*) m_malloc(sizeof(struct pam_response));
+			memset(resp, 0, sizeof(struct pam_response));
+
+			/* Safe to just use the direct pointer (no strdup) since
+			 * it shouldn't be getting munged at all */
+			resp->resp = userDatap->passwd;
+			(*respp) = resp;
+			break;
+
+
+		case PAM_PROMPT_ECHO_ON:
+
+			if ((strcmp(message, "login: " ) != 0)
+					&& (strcmp(message, "login:" ) != 0)
+					&& (strcmp(message, "Please enter username: " ) != 0)) {
+				TRACE(("PAM_PROMPT_ECHO_ON: unrecognized prompt"));
+				rc = PAM_CONV_ERR;
+				break;
+			}
+
+			/* This looks leaky, but the PAM module-writer docs
+			 * assure us that the caller will free it... */
+			resp = (struct pam_response*) m_malloc(sizeof(struct pam_response));
+			memset(resp, 0, sizeof(struct pam_response));
+
+			/* Safe to just use the direct pointer (no strdup) since
+			 * it shouldn't be getting munged at all */
+			resp->resp = userDatap->user;
+			TRACE(("userDatap->user='%s'", userDatap->user));
+			(*respp) = resp;
+			break;
+
+		default:
+			TRACE(("Unknown message type"));
+			rc = PAM_CONV_ERR;
+			break;
+	}
+
+	TRACE(("leave pamConvFunc, rc %d", rc));
+
+	return rc;
+}
+
+/* Process a password auth request, sending success or failure messages as
+ * appropriate. To the client it looks like it's doing normal password auth (as
+ * opposed to keyboard-interactive or something), so the pam module has to be
+ * fairly standard (ie just "what's your username, what's your password, OK").
+ *
+ * Keyboard interactive would be a lot nicer, but since PAM is synchronous, it
+ * gets very messy trying to send the interactive challenges, and read the
+ * interactive responses, over the network. */
+void svr_auth_pam() {
+
+	struct UserDataS userData;
+	struct pam_conv pamConv = {
+		pamConvFunc,
+		&userData /* submitted to pamvConvFunc as appdata_ptr */
+	};
+
+	pam_handle_t* pamHandlep = NULL;
+
+	unsigned char * password = NULL;
+	unsigned int passwordlen;
+
+	int rc = PAM_SUCCESS;
+	unsigned char changepw;
+
+	/* check if client wants to change password */
+	changepw = buf_getbyte(ses.payload);
+	if (changepw) {
+		/* not implemented by this server */
+		send_msg_userauth_failure(0, 1);
+		goto cleanup;
+	}
+
+	password = buf_getstring(ses.payload, &passwordlen);
+
+	/* used to pass data to the PAM conversation function */
+	userData.user = ses.authstate.printableuser;
+	userData.passwd = password;
+
+	/* Init pam */
+	if ((rc = pam_start("sshd", NULL, &pamConv, &pamHandlep)) != PAM_SUCCESS) {
+		dropbear_log(LOG_WARNING, "pam_start() failed, rc=%d, %s\n",
+				rc, pam_strerror(pamHandlep, rc));
+		goto cleanup;
+	}
+
+	/* just to set it to something */
+	if ((rc = pam_set_item(pamHandlep, PAM_TTY, "ssh") != PAM_SUCCESS)) {
+		dropbear_log(LOG_WARNING, "pam_set_item() failed, rc=%d, %s\n",
+				rc, pam_strerror(pamHandlep, rc));
+		goto cleanup;
+	}
+
+	(void) pam_fail_delay(pamHandlep, 0 /* musec_delay */);
+
+	/* (void) pam_set_item(pamHandlep, PAM_FAIL_DELAY, (void*) pamDelayFunc); */
+
+	if ((rc = pam_authenticate(pamHandlep, 0)) != PAM_SUCCESS) {
+		dropbear_log(LOG_WARNING, "pam_authenticate() failed, rc=%d, %s\n",
+				rc, pam_strerror(pamHandlep, rc));
+		dropbear_log(LOG_WARNING,
+				"bad pam password attempt for '%s'",
+				ses.authstate.printableuser);
+		send_msg_userauth_failure(0, 1);
+		goto cleanup;
+	}
+
+	if ((rc = pam_acct_mgmt(pamHandlep, 0)) != PAM_SUCCESS) {
+		dropbear_log(LOG_WARNING, "pam_acct_mgmt() failed, rc=%d, %s\n",
+				rc, pam_strerror(pamHandlep, rc));
+		dropbear_log(LOG_WARNING,
+				"bad pam password attempt for '%s'",
+				ses.authstate.printableuser);
+		send_msg_userauth_failure(0, 1);
+		goto cleanup;
+	}
+
+	/* successful authentication */
+	dropbear_log(LOG_NOTICE, "pam password auth succeeded for '%s'",
+			ses.authstate.printableuser);
+	send_msg_userauth_success();
+
+cleanup:
+	if (password != NULL) {
+		m_burn(password, passwordlen);
+		m_free(password);
+	}
+	if (pamHandlep != NULL) {
+		(void) pam_end(pamHandlep, 0 /* pam_status */);
+	}
+}
============================================================
--- Makefile.in	cbca06faeb152aa4d8b47590e096d52f7fd7dfda
+++ Makefile.in	597afdd77f8936704ae8e3721dd800d7e0f722bf
@@ -24,7 +24,7 @@ SVROBJS=svr-kex.o svr-algo.o svr-auth.o
 SVROBJS=svr-kex.o svr-algo.o svr-auth.o sshpty.o \
 		svr-authpasswd.o svr-authpubkey.o svr-session.o svr-service.o \
 		svr-chansession.o svr-runopts.o svr-agentfwd.o svr-main.o svr-x11fwd.o\
-		svr-tcpfwd.o
+		svr-tcpfwd.o svr-authpam.o

 CLIOBJS=cli-algo.o cli-main.o cli-auth.o cli-authpasswd.o cli-kex.o \
 		cli-session.o cli-service.o cli-runopts.o cli-chansession.o \
============================================================
--- auth.h	42a641e0c3b3027858c3f8e8e717cca76b7eddd8
+++ auth.h	ff1ddd99ccdd09f16eabf2e22e5384dabf33543d
@@ -36,6 +36,7 @@ void svr_auth_pubkey();
 void send_msg_userauth_success();
 void svr_auth_password();
 void svr_auth_pubkey();
+void svr_auth_pam();

 /* Client functions */
 void recv_msg_userauth_failure();
============================================================
--- configure.in	f3d9be07f83d1adafab1c522bb5459e028d6efc6
+++ configure.in	2dab0af5acf2a9845f1c249c5c10e0fc7b8c1e2e
@@ -117,6 +117,43 @@ AC_ARG_ENABLE(zlib,
 	]
 )

+# Check if pam is needed
+AC_ARG_WITH(pam,
+	[  --with-pam=PATH        Use pam in PATH],
+	[
+		# option is given
+		if test -d "$withval/lib"; then
+			LDFLAGS="-L${withval}/lib ${LDFLAGS}"
+		else
+			LDFLAGS="-L${withval} ${LDFLAGS}"
+		fi
+		if test -d "$withval/include"; then
+			CPPFLAGS="-I${withval}/include ${CPPFLAGS}"
+		else
+			CPPFLAGS="-I${withval} ${CPPFLAGS}"
+		fi
+	]
+)
+
+
+AC_ARG_ENABLE(pam,
+	[  --enable-pam          Try to include PAM support],
+	[
+		if test "x$enableval" = "xyes"; then
+			AC_CHECK_LIB(pam, pam_authenticate, , AC_MSG_ERROR([*** PAM missing - install first or check config.log ***]))
+			AC_MSG_RESULT(Enabling PAM)
+		else
+			AC_DEFINE(DISABLE_PAM,, Use PAM)
+			AC_MSG_RESULT(Disabling PAM)
+		fi
+	],
+	[
+		# disable it by default
+		AC_DEFINE(DISABLE_PAM,, Use PAM)
+		AC_MSG_RESULT(Disabling PAM)
+	]
+)
+
 AC_ARG_ENABLE(openpty,
 	[  --disable-openpty       Don't use openpty, use alternative method],
 	[
@@ -169,7 +206,7 @@ AC_HEADER_SYS_WAIT
 # Checks for header files.
 AC_HEADER_STDC
 AC_HEADER_SYS_WAIT
-AC_CHECK_HEADERS([fcntl.h limits.h netinet/in.h netinet/tcp.h stdlib.h string.h sys/socket.h sys/time.h termios.h unistd.h crypt.h pty.h ioctl.h libutil.h libgen.h inttypes.h stropts.h utmp.h utmpx.h lastlog.h paths.h util.h netdb.h])
+AC_CHECK_HEADERS([fcntl.h limits.h netinet/in.h netinet/tcp.h stdlib.h string.h sys/socket.h sys/time.h termios.h unistd.h crypt.h pty.h ioctl.h libutil.h libgen.h inttypes.h stropts.h utmp.h utmpx.h lastlog.h paths.h util.h netdb.h security/pam_appl.h pam/pam_appl.h])

 # Checks for typedefs, structures, and compiler characteristics.
 AC_C_CONST
============================================================
--- options.h	586757c4c005905a36d6900b1857a297c010d0e9
+++ options.h	64a6ffbbed9f9bdf520a8b2b33f903ae63200cf3
@@ -110,9 +110,19 @@ etc) slower (perhaps by 50%). Recommende
 #define MOTD_FILENAME "/etc/motd"
 #endif

-/* Authentication types to enable, at least one required.
+/* Authentication Types - at least one required.
    RFC Draft requires pubkey auth, and recommends password */
-#define ENABLE_SVR_PASSWORD_AUTH
+
+/* PAM auth is quite simple, and only works for PAM modules which just do a
+ * simple "Login: " "Password: " (or something like that - if your module is
+ * similar but not quite like that, edit the strings in svr-authpam.c).
+ * Basically, it's useful for systems like OS X where standard password crypts
+ * don't work, but there's and interface via a PAM module. You'll need to
+ * configure with --enable-pam as well, since it's off by default. And you
+ * should only enable either PASSWORD _or_ PAM auth, not both. */
+
+/*#define ENABLE_SVR_PASSWORD_AUTH*/
+#define ENABLE_SVR_PAM_AUTH
 #define ENABLE_SVR_PUBKEY_AUTH

 #define ENABLE_CLI_PASSWORD_AUTH
@@ -173,7 +183,7 @@ etc) slower (perhaps by 50%). Recommende
  *******************************************************************/

 #ifndef DROPBEAR_VERSION
-#define DROPBEAR_VERSION "0.44test3"
+#define DROPBEAR_VERSION "0.44rez1"
 #endif

 #define LOCAL_IDENT "SSH-2.0-dropbear_" DROPBEAR_VERSION
@@ -322,6 +332,10 @@ etc) slower (perhaps by 50%). Recommende
 #define DROPBEAR_KEY_LINES /* ie we're using authorized_keys or known_hosts */
 #endif

+#if defined(ENABLE_SVR_PASSWORD_AUTH) && defined(ENABLE_SVR_PAM_AUTH)
+#error "You can't turn on PASSWORD and PAM auth both at once. Fix it in options.h"
+#endif
+
 /* We use dropbear_client and dropbear_server as shortcuts to avoid redundant
  * code, if we're just compiling as client or server */
 #if defined(DROPBEAR_SERVER) && defined(DROPBEAR_CLIENT)
============================================================
--- svr-auth.c	86f05f7a7df1de1108492ed86ba038e5a2d82eaa
+++ svr-auth.c	aa0862ce0910cee5bfb9c0f57d1c482c9370c225
@@ -55,7 +55,7 @@ static void authclear() {
 #ifdef ENABLE_SVR_PUBKEY_AUTH
 	ses.authstate.authtypes |= AUTH_TYPE_PUBKEY;
 #endif
-#ifdef ENABLE_SVR_PASSWORD_AUTH
+#if defined(ENABLE_SVR_PASSWORD_AUTH) || defined(ENABLE_SVR_PAM_AUTH)
 	if (!svr_opts.noauthpass) {
 		ses.authstate.authtypes |= AUTH_TYPE_PASSWORD;
 	}
@@ -154,6 +154,19 @@ void recv_msg_userauth_request() {
 	}
 #endif

+#ifdef ENABLE_SVR_PAM_AUTH
+	if (!svr_opts.noauthpass &&
+			!(svr_opts.norootpass && ses.authstate.pw->pw_uid == 0) ) {
+		/* user wants to try password auth */
+		if (methodlen == AUTH_METHOD_PASSWORD_LEN &&
+				strncmp(methodname, AUTH_METHOD_PASSWORD,
+					AUTH_METHOD_PASSWORD_LEN) == 0) {
+			svr_auth_pam();
+			goto out;
+		}
+	}
+#endif
+
 #ifdef ENABLE_SVR_PUBKEY_AUTH
 	/* user wants to try pubkey auth */
 	if (methodlen == AUTH_METHOD_PUBKEY_LEN &&
============================================================
--- svr-runopts.c	0dc09806e7b620e96f83e49a6c18af83ad1b887f
+++ svr-runopts.c	d4a122f8fbe9a29b5bf8c4fa05f0a938edbeba07
@@ -59,7 +59,7 @@ static void printhelp(const char * progn
 					"-m		Don't display the motd on login\n"
 #endif
 					"-w		Disallow root logins\n"
-#ifdef ENABLE_SVR_PASSWORD_AUTH
+#if defined(ENABLE_SVR_PASSWORD_AUTH) || defined(ENABLE_SVR_PAM_AUTH)
 					"-s		Disable password logins\n"
 					"-g		Disable password logins for root\n"
 #endif
@@ -183,7 +183,7 @@ void svr_getopts(int argc, char ** argv)
 				case 'w':
 					svr_opts.norootlogin = 1;
 					break;
-#ifdef ENABLE_SVR_PASSWORD_AUTH
+#if defined(ENABLE_SVR_PASSWORD_AUTH) || defined(ENABLE_SVR_PAM_AUTH)
 				case 's':
 					svr_opts.noauthpass = 1;
 					break;