1 files changed, 223 insertions, 0 deletions
diff --git a/src/local/include.c b/src/local/include.c
new file mode 100644
index 0000000..a213d3c
--- /dev/null
+++ b/src/local/include.c
@@ -0,0 +1,223 @@
+/*++
+/* NAME
+/*	deliver_include 3
+/* SUMMARY
+/*	deliver to addresses listed in include file
+/* SYNOPSIS
+/*	#include "local.h"
+/*
+/*	int	deliver_include(state, usr_attr, path)
+/*	LOCAL_STATE state;
+/*	USER_ATTR usr_attr;
+/*	char	*path;
+/* DESCRIPTION
+/*	deliver_include() processes the contents of the named include
+/*	file and delivers to each address listed. Some sanity checks
+/*	are done on the include file permissions and type.
+/*
+/*	Arguments:
+/* .IP state
+/*	The attributes that specify the message, recipient and more.
+/*	Attributes describing alias, include, or forward expansion.
+/*	A table with the results from expanding aliases or lists.
+/*	A table with delivered-to: addresses taken from the message.
+/* .IP usr_attr
+/*	Attributes describing user rights and environment.
+/* .IP path
+/*	Pathname of the include file.
+/* DIAGNOSTICS
+/*	Fatal errors: out of memory. Warnings: bad include file type
+/*	or permissions. The result is non-zero when delivery should be
+/*	tried again.
+/* SEE ALSO
+/*	token(3) tokenize list
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <sys/stat.h>
+#include <unistd.h>
+#include <string.h>
+#include <fcntl.h>
+#include <errno.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <htable.h>
+#include <mymalloc.h>
+#include <vstream.h>
+#include <open_as.h>
+#include <stat_as.h>
+#include <iostuff.h>
+#include <mypwd.h>
+
+/* Global library. */
+
+#include <bounce.h>
+#include <defer.h>
+#include <been_here.h>
+#include <mail_params.h>
+#include <ext_prop.h>
+#include <sent.h>
+
+/* Application-specific. */
+
+#include "local.h"
+
+/* deliver_include - open include file and deliver */
+
+int     deliver_include(LOCAL_STATE state, USER_ATTR usr_attr, char *path)
+{
+    const char *myname = "deliver_include";
+    struct stat st;
+    struct mypasswd *file_pwd = 0;
+    int     status;
+    VSTREAM *fp;
+    int     fd;
+
+    /*
+     * Make verbose logging easier to understand.
+     */
+    state.level++;
+    if (msg_verbose)
+	MSG_LOG_STATE(myname, state);
+
+    /*
+     * DUPLICATE ELIMINATION
+     * 
+     * Don't process this include file more than once as this particular user.
+     */
+    if (been_here(state.dup_filter, "include %ld %s", (long) usr_attr.uid, path))
+	return (0);
+    state.msg_attr.exp_from = state.msg_attr.local;
+
+    /*
+     * Can of worms. Allow this include file to be symlinked, but disallow
+     * inclusion of special files or of files with world write permission
+     * enabled.
+     */
+    if (*path != '/') {
+	msg_warn(":include:%s uses a relative path", path);
+	dsb_simple(state.msg_attr.why, "5.3.5",
+		   "mail system configuration error");
+	return (bounce_append(BOUNCE_FLAGS(state.request),
+			      BOUNCE_ATTR(state.msg_attr)));
+    }
+    if (stat_as(path, &st, usr_attr.uid, usr_attr.gid) < 0) {
+	msg_warn("unable to lookup :include: file %s: %m", path);
+	dsb_simple(state.msg_attr.why, "5.3.5",
+		   "mail system configuration error");
+	return (bounce_append(BOUNCE_FLAGS(state.request),
+			      BOUNCE_ATTR(state.msg_attr)));
+    }
+    if (S_ISREG(st.st_mode) == 0) {
+	msg_warn(":include: file %s is not a regular file", path);
+	dsb_simple(state.msg_attr.why, "5.3.5",
+		   "mail system configuration error");
+	return (bounce_append(BOUNCE_FLAGS(state.request),
+			      BOUNCE_ATTR(state.msg_attr)));
+    }
+    if (st.st_mode & S_IWOTH) {
+	msg_warn(":include: file %s is world writable", path);
+	dsb_simple(state.msg_attr.why, "5.3.5",
+		   "mail system configuration error");
+	return (bounce_append(BOUNCE_FLAGS(state.request),
+			      BOUNCE_ATTR(state.msg_attr)));
+    }
+
+    /*
+     * DELIVERY POLICY
+     * 
+     * Set the expansion type attribute so that we can decide if destinations
+     * such as /file/name and |command are allowed at all.
+     */
+    state.msg_attr.exp_type = EXPAND_TYPE_INCL;
+
+    /*
+     * DELIVERY RIGHTS
+     * 
+     * When a non-root include file is listed in a root-owned alias, use the
+     * rights of the include file owner.  We do not want to give the include
+     * file owner control of the default account.
+     * 
+     * When an include file is listed in a user-owned alias or .forward file,
+     * leave the delivery rights alone. Users should not be able to make
+     * things happen with someone else's rights just by including some file
+     * that is owned by their victim.
+     */
+    if (usr_attr.uid == 0) {
+	if ((errno = mypwuid_err(st.st_uid, &file_pwd)) != 0 || file_pwd == 0) {
+	    msg_warn(errno ? "cannot find username for uid %ld: %m" :
+		     "cannot find username for uid %ld", (long) st.st_uid);
+	    msg_warn("%s: cannot find :include: file owner username", path);
+	    dsb_simple(state.msg_attr.why, "4.3.5",
+		       "mail system configuration error");
+	    return (defer_append(BOUNCE_FLAGS(state.request),
+				 BOUNCE_ATTR(state.msg_attr)));
+	}
+	if (file_pwd->pw_uid != 0)
+	    SET_USER_ATTR(usr_attr, file_pwd, state.level);
+    }
+
+    /*
+     * MESSAGE FORWARDING
+     * 
+     * When no owner attribute is set (either via an owner- alias, or as part of
+     * .forward file processing), set the owner attribute, to disable direct
+     * delivery of local recipients. By now it is clear that the owner
+     * attribute should have been called forwarder instead.
+     */
+    if (state.msg_attr.owner == 0)
+	state.msg_attr.owner = state.msg_attr.rcpt.address;
+
+    /*
+     * From here on no early returns or we have a memory leak.
+     * 
+     * FILE OPEN RIGHTS
+     * 
+     * Use the delivery rights to open the include file. When no delivery rights
+     * were established sofar, the file containing the :include: is owned by
+     * root, so it should be OK to open any file that is accessible to root.
+     * The command and file delivery routines are responsible for setting the
+     * proper delivery rights. These are the rights of the default user, in
+     * case the :include: is in a root-owned alias.
+     * 
+     * Don't propagate unmatched extensions unless permitted to do so.
+     */
+#define FOPEN_AS(p,u,g) ((fd = open_as(p,O_RDONLY,0,u,g)) >= 0 ? \
+				vstream_fdopen(fd,O_RDONLY) : 0)
+
+    if ((fp = FOPEN_AS(path, usr_attr.uid, usr_attr.gid)) == 0) {
+	msg_warn("cannot open include file %s: %m", path);
+	dsb_simple(state.msg_attr.why, "5.3.5",
+		   "mail system configuration error");
+	status = bounce_append(BOUNCE_FLAGS(state.request),
+			       BOUNCE_ATTR(state.msg_attr));
+    } else {
+	if ((local_ext_prop_mask & EXT_PROP_INCLUDE) == 0)
+	    state.msg_attr.unmatched = 0;
+	close_on_exec(vstream_fileno(fp), CLOSE_ON_EXEC);
+	status = deliver_token_stream(state, usr_attr, fp, (int *) 0);
+	if (vstream_fclose(fp))
+	    msg_warn("close %s: %m", path);
+    }
+
+    /*
+     * Cleanup.
+     */
+    if (file_pwd)
+	mypwfree(file_pwd);
+
+    return (status);
+}