struct mypasswd *mypwuid(uid_t uid)
{
struct mypasswd *mypwd;
while ((errno = mypwuid_err(uid, &mypwd)) != 0) {
msg_warn("getpwuid_r: %m");
sleep(MYPWD_ERROR_DELAY);
}
return (mypwd);
}
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);
}