rcolebaugh / rpms / openssh

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diff -up openssh-6.3p1/HOWTO.ssh-keycat.keycat openssh-6.3p1/HOWTO.ssh-keycat
--- openssh-6.3p1/HOWTO.ssh-keycat.keycat	2013-10-10 15:16:33.445566916 +0200
+++ openssh-6.3p1/HOWTO.ssh-keycat	2013-10-10 15:16:33.445566916 +0200
@@ -0,0 +1,12 @@
+The ssh-keycat retrieves the content of the ~/.ssh/authorized_keys
+of an user in any environment. This includes environments with
+polyinstantiation of home directories and SELinux MLS policy enabled.
+
+To use ssh-keycat, set these options in /etc/ssh/sshd_config file:
+        AuthorizedKeysCommand /usr/libexec/openssh/ssh-keycat
+        AuthorizedKeysCommandUser root
+
+Do not forget to enable public key authentication:
+        PubkeyAuthentication yes
+
+
diff -up openssh-6.3p1/Makefile.in.keycat openssh-6.3p1/Makefile.in
--- openssh-6.3p1/Makefile.in.keycat	2013-10-10 15:16:33.442566930 +0200
+++ openssh-6.3p1/Makefile.in	2013-10-10 15:16:33.445566916 +0200
@@ -27,6 +27,7 @@ SFTP_SERVER=$(libexecdir)/sftp-server
 SSH_KEYSIGN=$(libexecdir)/ssh-keysign
 SSH_LDAP_HELPER=$(libexecdir)/ssh-ldap-helper
 SSH_LDAP_WRAPPER=$(libexecdir)/ssh-ldap-wrapper
+SSH_KEYCAT=$(libexecdir)/ssh-keycat
 SSH_PKCS11_HELPER=$(libexecdir)/ssh-pkcs11-helper
 PRIVSEP_PATH=@PRIVSEP_PATH@
 SSH_PRIVSEP_USER=@SSH_PRIVSEP_USER@
@@ -64,7 +65,7 @@ EXEEXT=@EXEEXT@
 MANFMT=@MANFMT@
 INSTALL_SSH_LDAP_HELPER=@INSTALL_SSH_LDAP_HELPER@
 
-TARGETS=ssh$(EXEEXT) sshd$(EXEEXT) ssh-add$(EXEEXT) ssh-keygen$(EXEEXT) ssh-keyscan${EXEEXT} ssh-keysign${EXEEXT} ssh-pkcs11-helper$(EXEEXT) ssh-agent$(EXEEXT) scp$(EXEEXT) sftp-server$(EXEEXT) sftp$(EXEEXT) ssh-ldap-helper$(EXEEXT)
+TARGETS=ssh$(EXEEXT) sshd$(EXEEXT) ssh-add$(EXEEXT) ssh-keygen$(EXEEXT) ssh-keyscan${EXEEXT} ssh-keysign${EXEEXT} ssh-pkcs11-helper$(EXEEXT) ssh-agent$(EXEEXT) scp$(EXEEXT) sftp-server$(EXEEXT) sftp$(EXEEXT) ssh-ldap-helper$(EXEEXT) ssh-keycat$(EXEEXT)
 
 LIBSSH_OBJS=authfd.o authfile.o bufaux.o bufbn.o buffer.o \
 	canohost.o channels.o cipher.o cipher-aes.o \
@@ -172,6 +173,9 @@ ssh-pkcs11-helper$(EXEEXT): $(LIBCOMPAT)
 ssh-ldap-helper$(EXEEXT): $(LIBCOMPAT) libssh.a ldapconf.o ldapbody.o ldapmisc.o ldap-helper.o
 	$(LD) -o $@ ldapconf.o ldapbody.o ldapmisc.o ldap-helper.o $(LDFLAGS) -lssh -lopenbsd-compat -lfipscheck $(LIBS)
 
+ssh-keycat$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-keycat.o
+	$(LD) -o $@ ssh-keycat.o $(LDFLAGS) -lssh -lopenbsd-compat -lssh -lfipscheck $(SSHDLIBS)
+
 ssh-keyscan$(EXEEXT): $(LIBCOMPAT) libssh.a ssh-keyscan.o roaming_dummy.o
 	$(LD) -o $@ ssh-keyscan.o roaming_dummy.o $(LDFLAGS) -lssh -lopenbsd-compat -lssh $(LIBS)
 
@@ -279,6 +283,7 @@ install-files:
 		$(INSTALL) -m 0700 $(STRIP_OPT) ssh-ldap-helper $(DESTDIR)$(SSH_LDAP_HELPER) ; \
 		$(INSTALL) -m 0700 ssh-ldap-wrapper $(DESTDIR)$(SSH_LDAP_WRAPPER) ; \
 	fi
+	$(INSTALL) -m 0755 $(STRIP_OPT) ssh-keycat$(EXEEXT) $(DESTDIR)$(libexecdir)/ssh-keycat$(EXEEXT)
 	$(INSTALL) -m 0755 $(STRIP_OPT) sftp$(EXEEXT) $(DESTDIR)$(bindir)/sftp$(EXEEXT)
 	$(INSTALL) -m 0755 $(STRIP_OPT) sftp-server$(EXEEXT) $(DESTDIR)$(SFTP_SERVER)$(EXEEXT)
 	$(INSTALL) -m 644 ssh.1.out $(DESTDIR)$(mandir)/$(mansubdir)1/ssh.1
diff -up openssh-6.3p1/auth2-pubkey.c.keycat openssh-6.3p1/auth2-pubkey.c
--- openssh-6.3p1/auth2-pubkey.c.keycat	2013-10-10 15:16:33.429566992 +0200
+++ openssh-6.3p1/auth2-pubkey.c	2013-10-10 15:16:33.445566916 +0200
@@ -606,6 +606,14 @@ user_key_command_allowed2(struct passwd
 			_exit(1);
 		}
 
+#ifdef WITH_SELINUX
+		if (ssh_selinux_setup_env_variables() < 0) {
+			error ("failed to copy environment:  %s",
+			    strerror(errno));
+			_exit(127);
+		}
+#endif
+
 		execl(options.authorized_keys_command,
 		    options.authorized_keys_command, user_pw->pw_name, NULL);
 
diff -up openssh-6.3p1/openbsd-compat/port-linux.c.keycat openssh-6.3p1/openbsd-compat/port-linux.c
--- openssh-6.3p1/openbsd-compat/port-linux.c.keycat	2013-10-10 15:16:33.435566964 +0200
+++ openssh-6.3p1/openbsd-compat/port-linux.c	2013-10-10 15:32:19.946065189 +0200
@@ -313,7 +313,7 @@ ssh_selinux_getctxbyname(char *pwname,
 
 /* Setup environment variables for pam_selinux */
 static int
-ssh_selinux_setup_pam_variables(void)
+ssh_selinux_setup_variables(int(*set_it)(const char *, const char *))
 {
 	const char *reqlvl;
 	char *role;
@@ -324,16 +324,16 @@ ssh_selinux_setup_pam_variables(void)
 
 	ssh_selinux_get_role_level(&role, &reqlvl);
 
-	rv = do_pam_putenv("SELINUX_ROLE_REQUESTED", role ? role : "");
+	rv = set_it("SELINUX_ROLE_REQUESTED", role ? role : "");
 
 	if (inetd_flag && !rexeced_flag) {
 		use_current = "1";
 	} else {
 		use_current = "";
-		rv = rv || do_pam_putenv("SELINUX_LEVEL_REQUESTED", reqlvl ? reqlvl: "");
+		rv = rv || set_it("SELINUX_LEVEL_REQUESTED", reqlvl ? reqlvl: "");
 	}
 
-	rv = rv || do_pam_putenv("SELINUX_USE_CURRENT_RANGE", use_current);
+	rv = rv || set_it("SELINUX_USE_CURRENT_RANGE", use_current);
 
 	if (role != NULL)
 		free(role);
@@ -341,6 +341,24 @@ ssh_selinux_setup_pam_variables(void)
 	return rv;
 }
 
+static int
+ssh_selinux_setup_pam_variables(void)
+{
+	return ssh_selinux_setup_variables(do_pam_putenv);
+}
+
+static int
+do_setenv(char *name, char *value)
+{
+	return setenv(name, value, 1);
+}
+
+int
+ssh_selinux_setup_env_variables(void)
+{
+	return ssh_selinux_setup_variables(do_setenv);
+}
+
 /* Set the execution context to the default for the specified user */
 void
 ssh_selinux_setup_exec_context(char *pwname)
diff -up openssh-6.3p1/ssh-keycat.c.keycat openssh-6.3p1/ssh-keycat.c
--- openssh-6.3p1/ssh-keycat.c.keycat	2013-10-10 15:16:33.446566911 +0200
+++ openssh-6.3p1/ssh-keycat.c	2013-10-10 15:16:33.446566911 +0200
@@ -0,0 +1,238 @@
+/*
+ * 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, and the entire permission notice in its entirety,
+ *    including the disclaimer of warranties.
+ * 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.
+ * 3. The name of the author may not be used to endorse or promote
+ *    products derived from this software without specific prior
+ *    written permission.
+ *
+ * ALTERNATIVELY, this product may be distributed under the terms of
+ * the GNU Public License, in which case the provisions of the GPL are
+ * required INSTEAD OF the above restrictions.  (This clause is
+ * necessary due to a potential bad interaction between the GPL and
+ * the restrictions contained in a BSD-style copyright.)
+ *
+ * THIS SOFTWARE IS PROVIDED ``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 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.
+ */
+
+/*
+ * Copyright (c) 2011 Red Hat, Inc.
+ * Written by Tomas Mraz <tmraz@redhat.com>
+*/
+
+#define _GNU_SOURCE
+
+#include "config.h"
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <pwd.h>
+#include <fcntl.h>
+#include <unistd.h>
+
+#include <security/pam_appl.h>
+
+#include "uidswap.h"
+#include "misc.h"
+
+#define ERR_USAGE 1
+#define ERR_PAM_START 2
+#define ERR_OPEN_SESSION 3
+#define ERR_CLOSE_SESSION 4
+#define ERR_PAM_END 5
+#define ERR_GETPWNAM 6
+#define ERR_MEMORY 7
+#define ERR_OPEN 8
+#define ERR_FILE_MODE 9
+#define ERR_FDOPEN 10
+#define ERR_STAT 11
+#define ERR_WRITE 12
+#define ERR_PAM_PUTENV 13
+#define BUFLEN 4096
+
+/* Just ignore the messages in the conversation function */
+static int
+dummy_conv(int num_msg, const struct pam_message **msgm,
+	   struct pam_response **response, void *appdata_ptr)
+{
+	struct pam_response *rsp;
+
+	(void)msgm;
+	(void)appdata_ptr;
+
+	if (num_msg <= 0)
+		return PAM_CONV_ERR;
+
+	/* Just allocate the array as empty responses */
+	rsp = calloc (num_msg, sizeof (struct pam_response));
+	if (rsp == NULL)
+		return PAM_CONV_ERR;
+
+	*response = rsp;
+	return PAM_SUCCESS;
+}
+
+static struct pam_conv conv = {
+	dummy_conv,
+	NULL
+};
+
+char *
+make_auth_keys_name(const struct passwd *pwd)
+{
+	char *fname;
+
+	if (asprintf(&fname, "%s/.ssh/authorized_keys", pwd->pw_dir) < 0)
+		return NULL;
+
+	return fname;
+}
+
+int
+dump_keys(const char *user)
+{
+	struct passwd *pwd;
+	int fd = -1;
+	FILE *f = NULL;
+	char *fname = NULL;
+	int rv = 0;
+	char buf[BUFLEN];
+	size_t len;
+	struct stat st;
+
+	if ((pwd = getpwnam(user)) == NULL) {
+		return ERR_GETPWNAM;
+	}
+
+	if ((fname = make_auth_keys_name(pwd)) == NULL) {
+		return ERR_MEMORY;
+	}
+
+	temporarily_use_uid(pwd);
+
+	if ((fd = open(fname, O_RDONLY|O_NONBLOCK|O_NOFOLLOW, 0)) < 0) {
+		rv = ERR_OPEN;
+		goto fail;
+	}
+
+	if (fstat(fd, &st) < 0) {
+		rv = ERR_STAT;
+		goto fail;
+	}
+
+	if (!S_ISREG(st.st_mode) || 
+		(st.st_uid != pwd->pw_uid && st.st_uid != 0)) {
+		rv = ERR_FILE_MODE;
+		goto fail;
+	}
+
+	unset_nonblock(fd);
+
+	if ((f = fdopen(fd, "r")) == NULL) {
+		rv = ERR_FDOPEN;
+		goto fail;
+	}
+
+	fd = -1;
+
+	while ((len = fread(buf, 1, sizeof(buf), f)) > 0) {
+		rv = fwrite(buf, 1, len, stdout) != len ? ERR_WRITE : 0;
+	}
+
+fail:
+	if (fd != -1)
+		close(fd);
+	if (f != NULL)
+		fclose(f);
+	free(fname);
+	restore_uid();
+	return rv;
+}
+
+static const char *env_names[] = { "SELINUX_ROLE_REQUESTED",
+	"SELINUX_LEVEL_REQUESTED",
+	"SELINUX_USE_CURRENT_RANGE"
+};
+
+extern char **environ;
+
+int
+set_pam_environment(pam_handle_t *pamh)
+{
+	int i;
+	size_t j;
+
+	for (j = 0; j < sizeof(env_names)/sizeof(env_names[0]); ++j) {
+		int len = strlen(env_names[j]);
+
+		for (i = 0; environ[i] != NULL; ++i) {
+			if (strncmp(env_names[j], environ[i], len) == 0 &&
+			    environ[i][len] == '=') {
+				if (pam_putenv(pamh, environ[i]) != PAM_SUCCESS)
+					return ERR_PAM_PUTENV;
+			}
+		}
+	}
+
+	return 0;
+}
+
+int
+main(int argc, char *argv[])
+{
+	pam_handle_t *pamh = NULL;
+	int retval;
+	int ev = 0;
+
+	if (argc != 2) {
+		fprintf(stderr, "Usage: %s <user-name>\n", argv[0]);
+		return ERR_USAGE;
+	}
+
+	retval = pam_start("ssh-keycat", argv[1], &conv, &pamh);
+	if (retval != PAM_SUCCESS) {
+		return ERR_PAM_START;
+	}
+
+	ev = set_pam_environment(pamh);
+	if (ev != 0)
+		goto finish;
+
+	retval = pam_open_session(pamh, PAM_SILENT);
+	if (retval != PAM_SUCCESS) {
+		ev = ERR_OPEN_SESSION;
+		goto finish;
+	}
+
+	ev = dump_keys(argv[1]);
+
+	retval = pam_close_session(pamh, PAM_SILENT);
+	if (retval != PAM_SUCCESS) {
+		ev = ERR_CLOSE_SESSION;
+	}
+
+finish:
+	retval = pam_end (pamh,retval);
+	if (retval != PAM_SUCCESS) {
+		ev = ERR_PAM_END;
+	}
+	return ev;
+}