Fix for new Kerberos4. Make a fist cut at PAM-ising while I'm here.

2 files changed, 145 insertions, 27 deletions

diff --git a/libexec/ftpd/Makefile b/libexec/ftpd/Makefile
index bd5453f..ad5d142 100644
--- a/libexec/ftpd/Makefile
+++ b/libexec/ftpd/Makefile
@@ -17,13 +17,11 @@ LSDIR=	../../bin/ls
 SRCS+=	ls.c cmp.c print.c stat_flags.c util.c
 CFLAGS+=-DINTERNAL_LS -Dmain=ls_main -I${.CURDIR}/${LSDIR}
 
-.if exists(${DESTDIR}/usr/lib/libkrb.a) && defined(MAKE_KERBEROS4)
-.PATH:  ${.CURDIR}/../../lib/libpam/modules/pam_kerberosIV
-SRCS+=	klogin.c
-LDADD+=	-lkrb -ldes -lcom_err
-DPADD+= ${LIBKRB} ${LIBDES} ${LIBCOM_ERR}
-CFLAGS+=-DKERBEROS
-DISTRIBUTION=	krb
+.if defined(NOPAM)
+CFLAGS+=-DNOPAM
+.else
+DPADD+= ${LIBPAM}
+LDADD+= ${MINUSLPAM}
 .endif
 
 .include <bsd.prog.mk>
diff --git a/libexec/ftpd/ftpd.c b/libexec/ftpd/ftpd.c
index 52321ef..0f9d20c 100644
--- a/libexec/ftpd/ftpd.c
+++ b/libexec/ftpd/ftpd.c
@@ -94,6 +94,10 @@ static const char rcsid[] =
 #include <skey.h>
 #endif
 
+#if !defined(NOPAM)
+#include <security/pam_appl.h>
+#endif
+
 #include "pathnames.h"
 #include "extern.h"
 
@@ -168,19 +172,13 @@ char	*ident = NULL;
 static char ttyline[20];
 char	*tty = ttyline;		/* for klogin */
 
-#ifdef KERBEROS
-int	 klogin __P((struct passwd *, char *, char *, char *));
+#if !defined(NOPAM)
+static int	auth_pam __P((struct passwd**, const char*));
 #endif
 
 struct	in_addr bind_address;
 char	*pid_file = NULL;
 
-#if defined(KERBEROS)
-int	notickets = 1;
-int	noticketsdontcomplain = 1;
-char	*krbtkfile_env = NULL;
-#endif
-
 /*
  * Timeout intervals for retrying connections
  * to hosts that don't accept PORT cmds.  This
@@ -914,6 +912,132 @@ end_login()
 	dochroot = 0;
 }
 
+#if !defined(NOPAM)
+
+/*
+ * the following code is stolen from imap-uw PAM authentication module and
+ * login.c
+ */
+#define COPY_STRING(s) (s ? strdup(s) : NULL)
+
+struct cred_t {
+	const char *uname;		/* user name */
+	const char *pass;		/* password */
+};
+typedef struct cred_t cred_t;
+
+static int
+auth_conv(int num_msg, const struct pam_message **msg,
+	  struct pam_response **resp, void *appdata)
+{
+	int i;
+	cred_t *cred = (cred_t *) appdata;
+	struct pam_response *reply =
+			malloc(sizeof(struct pam_response) * num_msg);
+
+	for (i = 0; i < num_msg; i++) {
+		switch (msg[i]->msg_style) {
+		case PAM_PROMPT_ECHO_ON:	/* assume want user name */
+			reply[i].resp_retcode = PAM_SUCCESS;
+			reply[i].resp = COPY_STRING(cred->uname);
+			/* PAM frees resp. */
+			break;
+		case PAM_PROMPT_ECHO_OFF:	/* assume want password */
+			reply[i].resp_retcode = PAM_SUCCESS;
+			reply[i].resp = COPY_STRING(cred->pass);
+			/* PAM frees resp. */
+			break;
+		case PAM_TEXT_INFO:
+		case PAM_ERROR_MSG:
+			reply[i].resp_retcode = PAM_SUCCESS;
+			reply[i].resp = NULL;
+			break;
+		default:			/* unknown message style */
+			free(reply);
+			return PAM_CONV_ERR;
+		}
+	}
+
+	*resp = reply;
+	return PAM_SUCCESS;
+}
+
+/*
+ * Attempt to authenticate the user using PAM.  Returns 0 if the user is
+ * authenticated, or 1 if not authenticated.  If some sort of PAM system
+ * error occurs (e.g., the "/etc/pam.conf" file is missing) then this
+ * function returns -1.  This can be used as an indication that we should
+ * fall back to a different authentication mechanism.
+ */
+static int
+auth_pam(struct passwd **ppw, const char *pass)
+{
+	pam_handle_t *pamh = NULL;
+	const char *tmpl_user;
+	const void *item;
+	int rval;
+	int e;
+	cred_t auth_cred = { (*ppw)->pw_name, pass };
+	struct pam_conv conv = { &auth_conv, &auth_cred };
+
+	e = pam_start("ftpd", (*ppw)->pw_name, &conv, &pamh);
+	if (e != PAM_SUCCESS) {
+		syslog(LOG_ERR, "pam_start: %s", pam_strerror(pamh, e));
+		return -1;
+	}
+
+	e = pam_authenticate(pamh, 0);
+	switch (e) {
+	case PAM_SUCCESS:
+		/*
+		 * With PAM we support the concept of a "template"
+		 * user.  The user enters a login name which is
+		 * authenticated by PAM, usually via a remote service
+		 * such as RADIUS or TACACS+.  If authentication
+		 * succeeds, a different but related "template" name
+		 * is used for setting the credentials, shell, and
+		 * home directory.  The name the user enters need only
+		 * exist on the remote authentication server, but the
+		 * template name must be present in the local password
+		 * database.
+		 *
+		 * This is supported by two various mechanisms in the
+		 * individual modules.  However, from the application's
+		 * point of view, the template user is always passed
+		 * back as a changed value of the PAM_USER item.
+		 */
+		if ((e = pam_get_item(pamh, PAM_USER, &item)) ==
+		    PAM_SUCCESS) {
+			tmpl_user = (const char *) item;
+			if (strcmp((*ppw)->pw_name, tmpl_user) != 0)
+				*ppw = getpwnam(tmpl_user);
+		} else
+			syslog(LOG_ERR, "Couldn't get PAM_USER: %s",
+			    pam_strerror(pamh, e));
+		rval = 0;
+		break;
+
+	case PAM_AUTH_ERR:
+	case PAM_USER_UNKNOWN:
+	case PAM_MAXTRIES:
+		rval = 1;
+		break;
+
+	default:
+		syslog(LOG_ERR, "auth_pam: %s", pam_strerror(pamh, e));
+		rval = -1;
+		break;
+	}
+
+	if ((e = pam_end(pamh, e)) != PAM_SUCCESS) {
+		syslog(LOG_ERR, "pam_end: %s", pam_strerror(pamh, e));
+		rval = -1;
+	}
+	return rval;
+}
+
+#endif /* !defined(NOPAM) */
+
 void
 pass(passwd)
 	char *passwd;
@@ -934,9 +1058,9 @@ pass(passwd)
 			rval = 1;	/* failure below */
 			goto skip;
 		}
-#if defined(KERBEROS)
-		rval = klogin(pw, "", hostname, passwd);
-		if (rval == 0)
+#if !defined(NOPAM)
+		rval = auth_pam(&pw, passwd);
+		if (rval >= 0)
 			goto skip;
 #endif
 #ifdef SKEY
@@ -953,7 +1077,7 @@ pass(passwd)
 skip:
 		/*
 		 * If rval == 1, the user failed the authentication check
-		 * above.  If rval == 0, either Kerberos or local authentication
+		 * above.  If rval == 0, either PAM or local authentication
 		 * succeeded.
 		 */
 		if (rval) {
@@ -1085,14 +1209,14 @@ skip:
 		if (thishost != firsthost)
 			snprintf(proctitle, sizeof(proctitle),
 				 "%s: anonymous(%s)/%.*s", remotehost, hostname,
-				 sizeof(proctitle) - sizeof(remotehost) -
-				 sizeof(": anonymous/"), passwd);
+				 (int)(sizeof(proctitle) - sizeof(remotehost) -
+				 sizeof(": anonymous/")), passwd);
 		else
 #endif
 			snprintf(proctitle, sizeof(proctitle),
 				 "%s: anonymous/%.*s", remotehost,
-				 sizeof(proctitle) - sizeof(remotehost) -
-				 sizeof(": anonymous/"), passwd);
+				 (int)(sizeof(proctitle) - sizeof(remotehost) -
+				 sizeof(": anonymous/")), passwd);
 		setproctitle("%s", proctitle);
 #endif /* SETPROCTITLE */
 		if (logging)
@@ -1937,10 +2061,6 @@ dologout(status)
 	if (logged_in) {
 		(void) seteuid((uid_t)0);
 		ftpd_logwtmp(ttyline, "", "");
-#if defined(KERBEROS)
-		if (!notickets && krbtkfile_env)
-			unlink(krbtkfile_env);
-#endif
 	}
 	/* beware of flushing buffers after a SIGPIPE */
 	_exit(status);