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diff --git a/src/modules/rlm_pam/rlm_pam.c b/src/modules/rlm_pam/rlm_pam.c
new file mode 100644
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--- /dev/null
+++ b/src/modules/rlm_pam/rlm_pam.c
@@ -0,0 +1,244 @@
+/*
+ *   This program is is free software; you can redistribute it and/or modify
+ *   it under the terms of the GNU General Public License as published by
+ *   the Free Software Foundation; either version 2 of the License, or (at
+ *   your option) any later version.
+ *
+ *   This program is distributed in the hope that it will be useful,
+ *   but WITHOUT ANY WARRANTY; without even the implied warranty of
+ *   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ *   GNU General Public License for more details.
+ *
+ *   You should have received a copy of the GNU General Public License
+ *   along with this program; if not, write to the Free Software
+ *   Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301, USA
+ */
+
+/**
+ * $Id$
+ * @file rlm_pam.c
+ * @brief Interfaces with the PAM library to allow auth via PAM.
+ *
+ * @note This was taken from the hacks that miguel a.l. paraz <map@iphil.net>
+ *	did on radiusd-cistron-1.5.3 and migrated to a separate file.
+ *	That, in fact, was again based on the original stuff from
+ *	Jeph Blaize <jblaize@kiva.net> done in May 1997.
+ *
+ * @copyright 2000,2006  The FreeRADIUS server project
+ * @copyright 1997  Jeph Blaize <jblaize@kiva.net>
+ * @copyright 1999  miguel a.l. paraz <map@iphil.net>
+ */
+RCSID("$Id$")
+
+#include <freeradius-devel/radiusd.h>
+#include <freeradius-devel/modules.h>
+
+#include "config.h"
+
+#ifdef HAVE_SECURITY_PAM_APPL_H
+#  include <security/pam_appl.h>
+#endif
+
+#ifdef HAVE_PAM_PAM_APPL_H
+#  include <pam/pam_appl.h>
+#endif
+
+#ifdef HAVE_SYSLOG_H
+#  include <syslog.h>
+#endif
+
+typedef struct rlm_pam_t {
+	char const *pam_auth_name;
+} rlm_pam_t;
+
+static const CONF_PARSER module_config[] = {
+	{ "pam_auth", FR_CONF_OFFSET(PW_TYPE_STRING, rlm_pam_t, pam_auth_name), "radiusd" },
+	CONF_PARSER_TERMINATOR
+};
+
+typedef struct rlm_pam_data_t {
+	REQUEST		*request;	//!< The current request.
+	char const	*username;	//!< Username to provide to PAM when prompted.
+	char const	*password;	//!< Password to provide to PAM when prompted.
+	bool		error;		//!< True if pam_conv failed.
+} rlm_pam_data_t;
+
+/** Dialogue between RADIUS and PAM modules
+ *
+ * Uses PAM's appdata_ptr so it's thread safe, and doesn't
+ * have any nasty static variables hanging around.
+ */
+static int pam_conv(int num_msg, struct pam_message const **msg, struct pam_response **resp, void *appdata_ptr)
+{
+	int count;
+	struct pam_response *reply;
+	REQUEST *request;
+	rlm_pam_data_t *pam_config = (rlm_pam_data_t *) appdata_ptr;
+
+	request = pam_config->request;
+
+/* strdup(NULL) doesn't work on some platforms */
+#define COPY_STRING(s) ((s) ? strdup(s) : NULL)
+
+	reply = rad_malloc(num_msg * sizeof(struct pam_response));
+	memset(reply, 0, num_msg * sizeof(struct pam_response));
+	for (count = 0; count < num_msg; count++) {
+		switch (msg[count]->msg_style) {
+		case PAM_PROMPT_ECHO_ON:
+			reply[count].resp_retcode = PAM_SUCCESS;
+			reply[count].resp = COPY_STRING(pam_config->username);
+			break;
+
+		case PAM_PROMPT_ECHO_OFF:
+			reply[count].resp_retcode = PAM_SUCCESS;
+			reply[count].resp = COPY_STRING(pam_config->password);
+			break;
+
+		case PAM_TEXT_INFO:
+			RDEBUG2("%s", msg[count]->msg);
+			break;
+
+		case PAM_ERROR_MSG:
+		default:
+			RERROR("PAM conversation failed");
+			/* Must be an error of some sort... */
+			for (count = 0; count < num_msg; count++) {
+				if (msg[count]->msg_style == PAM_ERROR_MSG) RERROR("%s", msg[count]->msg);
+				if (reply[count].resp) {
+	  				/* could be a password, let's be sanitary */
+	  				memset(reply[count].resp, 0, strlen(reply[count].resp));
+	  				free(reply[count].resp);
+				}
+			}
+			free(reply);
+			pam_config->error = true;
+			return PAM_CONV_ERR;
+		}
+	}
+	*resp = reply;
+	/* PAM frees reply (including reply[].resp) */
+
+	return PAM_SUCCESS;
+}
+
+/** Check the users password against the standard UNIX password table + PAM.
+ *
+ * @note For most flexibility, passing a pamauth type to this function
+ *	 allows you to have multiple authentication types (i.e. multiple
+ *	 files associated with radius in /etc/pam.d).
+ *
+ * @param request The current request.
+ * @param username User to authenticate.
+ * @param passwd Password to authenticate with,
+ * @param pamauth Type of PAM authentication.
+ * @return 0 on success -1 on failure.
+ */
+static int do_pam(REQUEST *request, char const *username, char const *passwd, char const *pamauth)
+{
+	pam_handle_t *handle = NULL;
+	int ret;
+	rlm_pam_data_t pam_config;
+	struct pam_conv conv;
+
+	/*
+	 *  Initialize the structures
+	 */
+	conv.conv = pam_conv;
+	conv.appdata_ptr = &pam_config;
+	pam_config.request = request;
+	pam_config.username = username;
+	pam_config.password = passwd;
+	pam_config.error = false;
+
+	RDEBUG2("Using pamauth string \"%s\" for pam.conf lookup", pamauth);
+
+	ret = pam_start(pamauth, username, &conv, &handle);
+	if (ret != PAM_SUCCESS) {
+		RERROR("pam_start failed: %s", pam_strerror(handle, ret));
+		return -1;
+	}
+
+	ret = pam_authenticate(handle, 0);
+	if (ret != PAM_SUCCESS) {
+		RERROR("pam_authenticate failed: %s", pam_strerror(handle, ret));
+		pam_end(handle, ret);
+		return -1;
+	}
+
+	/*
+	 *	FreeBSD 3.x doesn't have account and session management
+	 *	functions in PAM, while 4.0 does.
+	 */
+#if !defined(__FreeBSD_version) || (__FreeBSD_version >= 400000)
+	ret = pam_acct_mgmt(handle, 0);
+	if (ret != PAM_SUCCESS) {
+		RERROR("pam_acct_mgmt failed: %s", pam_strerror(handle, ret));
+		pam_end(handle, ret);
+		return -1;
+	}
+#endif
+	RDEBUG2("Authentication succeeded");
+	pam_end(handle, ret);
+	return 0;
+}
+
+static rlm_rcode_t CC_HINT(nonnull) mod_authenticate(void *instance, REQUEST *request)
+{
+	int ret;
+	VALUE_PAIR *pair;
+	rlm_pam_t *data = (rlm_pam_t *) instance;
+
+	char const *pam_auth_string = data->pam_auth_name;
+
+	/*
+	 *	We can only authenticate user requests which HAVE
+	 *	a User-Name attribute.
+	 */
+	if (!request->username) {
+		RAUTH("Attribute \"User-Name\" is required for authentication");
+		return RLM_MODULE_INVALID;
+	}
+
+	/*
+	 *	We can only authenticate user requests which HAVE
+	 *	a User-Password attribute.
+	 */
+	if (!request->password) {
+		RAUTH("Attribute \"User-Password\" is required for authentication");
+		return RLM_MODULE_INVALID;
+	}
+
+	/*
+	 *  Ensure that we're being passed a plain-text password,
+	 *  and not anything else.
+	 */
+	if (request->password->da->attr != PW_USER_PASSWORD) {
+		RAUTH("Attribute \"User-Password\" is required for authentication.  Cannot use \"%s\".", request->password->da->name);
+		return RLM_MODULE_INVALID;
+	}
+
+	/*
+	 *	Let the 'users' file over-ride the PAM auth name string,
+	 *	for backwards compatibility.
+	 */
+	pair = fr_pair_find_by_num(request->config, PW_PAM_AUTH, 0, TAG_ANY);
+	if (pair) pam_auth_string = pair->vp_strvalue;
+
+	ret = do_pam(request, request->username->vp_strvalue, request->password->vp_strvalue, pam_auth_string);
+	if (ret < 0) return RLM_MODULE_REJECT;
+
+	return RLM_MODULE_OK;
+}
+
+extern module_t rlm_pam;
+module_t rlm_pam = {
+	.magic		= RLM_MODULE_INIT,
+	.name		= "pam",
+	.type		= RLM_TYPE_THREAD_UNSAFE,	/* The PAM libraries are not thread-safe */
+	.inst_size	= sizeof(rlm_pam_t),
+	.config		= module_config,
+	.methods = {
+		[MOD_AUTHENTICATE]	= mod_authenticate
+	},
+};
+