This commit was manufactured by cvs2svn to create tag 'FreeBSD-release/1.1'.

[unix-history] / usr.sbin / sendmail / src / recipient.c

diff --git a/usr.sbin/sendmail/src/recipient.c b/usr.sbin/sendmail/src/recipient.c
index e80c6b5..98d800d 100644 (file)
--- a/usr.sbin/sendmail/src/recipient.c
+++ b/usr.sbin/sendmail/src/recipient.c
@@ -33,7 +33,7 @@
  */
 
 #ifndef lint
  */
 
 #ifndef lint

-static char sccsid[] = "@(#)recipient.c        8.21 (Berkeley) 10/29/93";
+static char sccsid[] = "@(#)recipient.c        8.44 (Berkeley) 2/28/94";

 #endif /* not lint */
 
 # include "sendmail.h"
 #endif /* not lint */
 
 # include "sendmail.h"


@@ -222,10 +222,25 @@ recipient(a, sendq, e)
        stripquotes(buf);
 
        /* check for direct mailing to restricted mailers */
        stripquotes(buf);
 
        /* check for direct mailing to restricted mailers */

-       if (a->q_alias == NULL && m == ProgMailer)
+       if (m == ProgMailer)

        {
        {

-               a->q_flags |= QBADADDR;
-               usrerr("550 Cannot mail directly to programs");
+               if (a->q_alias == NULL)
+               {
+                       a->q_flags |= QBADADDR;
+                       usrerr("550 Cannot mail directly to programs");
+               }
+               else if (bitset(QBOGUSSHELL, a->q_alias->q_flags))
+               {
+                       a->q_flags |= QBADADDR;
+                       usrerr("550 User %s@%s doesn't have a valid shell for mailing to programs",
+                               a->q_alias->q_ruser, MyHostName);
+               }
+               else if (bitset(QUNSAFEADDR, a->q_alias->q_flags))
+               {
+                       a->q_flags |= QBADADDR;
+                       usrerr("550 Address %s is unsafe for mailing to programs",
+                               a->q_alias->q_paddr);
+               }

        }
 
        /*
        }
 
        /*


@@ -252,6 +267,8 @@ recipient(a, sendq, e)
                                        message("duplicate suppressed");
                                q->q_flags |= a->q_flags;
                        }
                                        message("duplicate suppressed");
                                q->q_flags |= a->q_flags;
                        }

+                       else if (bitset(QSELFREF, q->q_flags))
+                               q->q_flags |= a->q_flags & ~QDONTSEND;

                        a = q;
                        goto testselfdestruct;
                }
                        a = q;
                        goto testselfdestruct;
                }


@@ -290,10 +307,12 @@ recipient(a, sendq, e)
                        {
 #ifdef LOG
                                if (LogLevel > 2)
                        {
 #ifdef LOG
                                if (LogLevel > 2)

-                                       syslog(LOG_ERR, "%s: include %s: transient error: %e",
-                                               e->e_id, a->q_user, errstring(ret));
+                                       syslog(LOG_ERR, "%s: include %s: transient error: %s",
+                                               e->e_id == NULL ? "NOQUEUE" : e->e_id,
+                                               a->q_user, errstring(ret));

 #endif
                                a->q_flags |= QQUEUEUP;
 #endif
                                a->q_flags |= QQUEUEUP;

+                               a->q_flags &= ~QDONTSEND;

                                usrerr("451 Cannot open %s: %s",
                                        a->q_user, errstring(ret));
                        }
                                usrerr("451 Cannot open %s: %s",
                                        a->q_user, errstring(ret));
                        }


@@ -307,18 +326,27 @@ recipient(a, sendq, e)
        }
        else if (m == FileMailer)
        {
        }
        else if (m == FileMailer)
        {

-               struct stat stb;

                extern bool writable();
 
                extern bool writable();
 

-               p = strrchr(buf, '/');

                /* check if writable or creatable */
                if (a->q_alias == NULL)
                {
                        a->q_flags |= QBADADDR;
                        usrerr("550 Cannot mail directly to files");
                }
                /* check if writable or creatable */
                if (a->q_alias == NULL)
                {
                        a->q_flags |= QBADADDR;
                        usrerr("550 Cannot mail directly to files");
                }

-               else if ((stat(buf, &stb) >= 0) ? (!writable(&stb)) :
-                   (*p = '\0', safefile(buf, RealUid, RealGid, NULL, TRUE, S_IWRITE|S_IEXEC) != 0))
+               else if (bitset(QBOGUSSHELL, a->q_alias->q_flags))
+               {
+                       a->q_flags |= QBADADDR;
+                       usrerr("550 User %s@%s doesn't have a valid shell for mailing to files",
+                               a->q_alias->q_ruser, MyHostName);
+               }
+               else if (bitset(QUNSAFEADDR, a->q_alias->q_flags))
+               {
+                       a->q_flags |= QBADADDR;
+                       usrerr("550 Address %s is unsafe for mailing to files",
+                               a->q_alias->q_paddr);
+               }
+               else if (!writable(buf, getctladdr(a), SFF_ANYFILE))

                {
                        a->q_flags |= QBADADDR;
                        giveresponse(EX_CANTCREAT, m, NULL, a->q_alias, e);
                {
                        a->q_flags |= QBADADDR;
                        giveresponse(EX_CANTCREAT, m, NULL, a->q_alias, e);


@@ -340,7 +368,6 @@ recipient(a, sendq, e)
        if (!bitset(QDONTSEND|QNOTREMOTE|QVERIFIED, a->q_flags))
        {
                extern int udbexpand();
        if (!bitset(QDONTSEND|QNOTREMOTE|QVERIFIED, a->q_flags))
        {
                extern int udbexpand();

-               extern int errno;

 
                if (udbexpand(a, sendq, e) == EX_TEMPFAIL)
                {
 
                if (udbexpand(a, sendq, e) == EX_TEMPFAIL)
                {


@@ -350,7 +377,8 @@ recipient(a, sendq, e)
 # ifdef LOG
                        if (LogLevel > 8)
                                syslog(LOG_INFO, "%s: deferred: udbexpand: %s",
 # ifdef LOG
                        if (LogLevel > 8)
                                syslog(LOG_INFO, "%s: deferred: udbexpand: %s",

-                                       e->e_id, errstring(errno));
+                                       e->e_id == NULL ? "NOQUEUE" : e->e_id,
+                                       errstring(errno));

 # endif
                        message("queued (user database error): %s",
                                errstring(errno));
 # endif
                        message("queued (user database error): %s",
                                errstring(errno));


@@ -421,7 +449,10 @@ recipient(a, sendq, e)
                                (void) strcpy(buf, pw->pw_name);
                                goto trylocaluser;
                        }
                                (void) strcpy(buf, pw->pw_name);
                                goto trylocaluser;
                        }

-                       a->q_home = newstr(pw->pw_dir);
+                       if (strcmp(pw->pw_dir, "/") == 0)
+                               a->q_home = "";
+                       else
+                               a->q_home = newstr(pw->pw_dir);

                        a->q_uid = pw->pw_uid;
                        a->q_gid = pw->pw_gid;
                        a->q_ruser = newstr(pw->pw_name);
                        a->q_uid = pw->pw_uid;
                        a->q_gid = pw->pw_gid;
                        a->q_ruser = newstr(pw->pw_name);


@@ -429,6 +460,11 @@ recipient(a, sendq, e)
                        buildfname(pw->pw_gecos, pw->pw_name, nbuf);
                        if (nbuf[0] != '\0')
                                a->q_fullname = newstr(nbuf);
                        buildfname(pw->pw_gecos, pw->pw_name, nbuf);
                        if (nbuf[0] != '\0')
                                a->q_fullname = newstr(nbuf);

+                       if (pw->pw_shell != NULL && pw->pw_shell[0] != '\0' &&
+                           !usershellok(pw->pw_shell))
+                       {
+                               a->q_flags |= QBOGUSSHELL;
+                       }

                        if (!quoted)
                                forward(a, sendq, e);
                }
                        if (!quoted)
                                forward(a, sendq, e);
                }


@@ -563,7 +599,9 @@ finduser(name, fuzzyp)
 **     not writable.  This is also enforced by mailfile.
 **
 **     Parameters:
 **     not writable.  This is also enforced by mailfile.
 **
 **     Parameters:

-**             s -- pointer to a stat struct for the file.
+**             filename -- the file name to check.
+**             ctladdr -- the controlling address for this file.
+**             flags -- SFF_* flags to control the function.

 **
 **     Returns:
 **             TRUE -- if we will be able to write this file.
 **
 **     Returns:
 **             TRUE -- if we will be able to write this file.


@@ -574,35 +612,98 @@ finduser(name, fuzzyp)
 */
 
 bool
 */
 
 bool

-writable(s)
-       register struct stat *s;
+writable(filename, ctladdr, flags)
+       char *filename;
+       ADDRESS *ctladdr;
+       int flags;

 {
        uid_t euid;
        gid_t egid;
        int bits;
 {
        uid_t euid;
        gid_t egid;
        int bits;

+       register char *p;
+       char *uname;
+       struct stat stb;
+       extern char RealUserName[];

 
 

-       if (bitset(0111, s->st_mode))
-               return (FALSE);
-       euid = RealUid;
-       egid = RealGid;
-       if (geteuid() == 0)
+       if (tTd(29, 5))
+               printf("writable(%s, %x)\n", filename, flags);
+
+#ifdef HASLSTAT
+       if ((bitset(SFF_NOSLINK, flags) ? lstat(filename, &stb)
+                                       : stat(filename, &stb)) < 0)
+#else
+       if (stat(filename, &stb) < 0)
+#endif

        {
        {

-               if (bitset(S_ISUID, s->st_mode))
-                       euid = s->st_uid;
-               if (bitset(S_ISGID, s->st_mode))
-                       egid = s->st_gid;
+               /* file does not exist -- see if directory is safe */
+               p = strrchr(filename, '/');
+               if (p == NULL)
+               {
+                       errno = ENOTDIR;
+                       return FALSE;
+               }
+               *p = '\0';
+               errno = safefile(filename, RealUid, RealGid, RealUserName,
+                                SFF_MUSTOWN, S_IWRITE|S_IEXEC);
+               *p = '/';
+               return errno == 0;

        }
 
        }
 

+#ifdef SUID_ROOT_FILES_OK
+       /* really ought to be passed down -- and not a good idea */
+       flags |= SFF_ROOTOK;
+#endif
+
+       /*
+       **  File does exist -- check that it is writable.
+       */
+
+       if (bitset(0111, stb.st_mode))
+       {
+               if (tTd(29, 5))
+                       printf("failed (mode %o: x bits)\n", stb.st_mode);
+               errno = EPERM;
+               return (FALSE);
+       }
+
+       if (ctladdr != NULL && geteuid() == 0)
+       {
+               euid = ctladdr->q_uid;
+               egid = ctladdr->q_gid;
+               uname = ctladdr->q_user;
+       }
+       else
+       {
+               euid = RealUid;
+               egid = RealGid;
+               uname = RealUserName;
+       }

        if (euid == 0)
        if (euid == 0)

-               return (TRUE);
-       bits = S_IWRITE;
-       if (euid != s->st_uid)

        {
        {

-               bits >>= 3;
-               if (egid != s->st_gid)
-                       bits >>= 3;
+               euid = DefUid;
+               uname = DefUser;
+       }
+       if (egid == 0)
+               egid = DefGid;
+       if (geteuid() == 0)
+       {
+               if (bitset(S_ISUID, stb.st_mode) &&
+                   (stb.st_uid != 0 || bitset(SFF_ROOTOK, flags)))
+               {
+                       euid = stb.st_uid;
+                       uname = NULL;
+               }
+               if (bitset(S_ISGID, stb.st_mode) &&
+                   (stb.st_gid != 0 || bitset(SFF_ROOTOK, flags)))
+                       egid = stb.st_gid;

        }
        }

-       return ((s->st_mode & bits) != 0);
+
+       if (tTd(29, 5))
+               printf("\teu/gid=%d/%d, st_u/gid=%d/%d\n",
+                       euid, egid, stb.st_uid, stb.st_gid);
+
+       errno = safefile(filename, euid, egid, uname, flags, S_IWRITE);
+       return errno == 0;

 }
 \f/*
 **  INCLUDE -- handle :include: specification.
 }
 \f/*
 **  INCLUDE -- handle :include: specification.


@@ -623,11 +724,33 @@ writable(s)
 **     Side Effects:
 **             reads the :include: file and sends to everyone
 **             listed in that file.
 **     Side Effects:
 **             reads the :include: file and sends to everyone
 **             listed in that file.

+**
+**     Security Note:
+**             If you have restricted chown (that is, you can't
+**             give a file away), it is reasonable to allow programs
+**             and files called from this :include: file to be to be
+**             run as the owner of the :include: file.  This is bogus
+**             if there is any chance of someone giving away a file.
+**             We assume that pre-POSIX systems can give away files.
+**
+**             There is an additional restriction that if you
+**             forward to a :include: file, it will not take on
+**             the ownership of the :include: file.  This may not
+**             be necessary, but shouldn't hurt.

 */
 
 static jmp_buf CtxIncludeTimeout;
 static int     includetimeout();
 
 */
 
 static jmp_buf CtxIncludeTimeout;
 static int     includetimeout();
 

+#ifndef S_IWOTH
+# define S_IWOTH       (S_IWRITE >> 6)
+#endif
+
+#if defined(__FreeBSD__) && defined(_POSIX_CHOWN_RESTRICTED)
+#      undef _POSIX_CHOWN_RESTRICTED
+#      define _POSIX_CHOWN_RESTRICTED 1
+#endif
+

 int
 include(fname, forwarding, ctladdr, sendq, e)
        char *fname;
 int
 include(fname, forwarding, ctladdr, sendq, e)
        char *fname;


@@ -647,7 +770,27 @@ include(fname, forwarding, ctladdr, sendq, e)
        gid_t savedgid, gid;
        char *uname;
        int rval = 0;
        gid_t savedgid, gid;
        char *uname;
        int rval = 0;

+       int sfflags = forwarding ? SFF_MUSTOWN : SFF_ANYFILE;
+       struct stat st;

        char buf[MAXLINE];
        char buf[MAXLINE];

+#ifdef _POSIX_CHOWN_RESTRICTED
+# if _POSIX_CHOWN_RESTRICTED == -1
+#  define safechown    FALSE
+# else
+#  define safechown    TRUE
+# endif
+#else
+# ifdef _PC_CHOWN_RESTRICTED
+       bool safechown;
+# else
+#  ifdef BSD
+#   define safechown   TRUE
+#  else
+#   define safechown   FALSE
+#  endif
+# endif
+#endif
+       extern bool chownsafe();

 
        if (tTd(27, 2))
                printf("include(%s)\n", fname);
 
        if (tTd(27, 2))
                printf("include(%s)\n", fname);


@@ -665,9 +808,9 @@ include(fname, forwarding, ctladdr, sendq, e)
        ca = getctladdr(ctladdr);
        if (ca == NULL)
        {
        ca = getctladdr(ctladdr);
        if (ca == NULL)
        {

-               uid = 0;
-               gid = 0;
-               uname = NULL;
+               uid = DefUid;
+               gid = DefGid;
+               uname = DefUser;

                saveduid = -1;
        }
        else
                saveduid = -1;
        }
        else


@@ -699,7 +842,6 @@ include(fname, forwarding, ctladdr, sendq, e)
        {
                ctladdr->q_flags |= QQUEUEUP;
                errno = 0;
        {
                ctladdr->q_flags |= QQUEUEUP;
                errno = 0;

-               usrerr("451 open timeout on %s", fname);

 
                /* return pseudo-error code */
                rval = EOPENTIMEOUT;
 
                /* return pseudo-error code */
                rval = EOPENTIMEOUT;


@@ -708,41 +850,24 @@ include(fname, forwarding, ctladdr, sendq, e)
        ev = setevent((time_t) 60, includetimeout, 0);
 
        /* the input file must be marked safe */
        ev = setevent((time_t) 60, includetimeout, 0);
 
        /* the input file must be marked safe */

-       rval = safefile(fname, uid, gid, uname, forwarding, S_IREAD);
+       rval = safefile(fname, uid, gid, uname, sfflags, S_IREAD);

        if (rval != 0)
        {
                /* don't use this :include: file */
        if (rval != 0)
        {
                /* don't use this :include: file */

-               clrevent(ev);

                if (tTd(27, 4))
                        printf("include: not safe (uid=%d): %s\n",
                                uid, errstring(rval));
                if (tTd(27, 4))
                        printf("include: not safe (uid=%d): %s\n",
                                uid, errstring(rval));

-               goto resetuid;
-       }
-
-       fp = fopen(fname, "r");
-       if (fp == NULL)
-       {
-               rval = errno;
-               if (tTd(27, 4))
-                       printf("include: open: %s\n", errstring(rval));

        }
        }

-       else if (ca == NULL)
+       else

        {
        {

-               struct stat st;
-
-               if (fstat(fileno(fp), &st) < 0)
+               fp = fopen(fname, "r");
+               if (fp == NULL)

                {
                        rval = errno;
                {
                        rval = errno;

-                       syserr("Cannot fstat %s!", fname);
-               }
-               else
-               {
-                       ctladdr->q_uid = st.st_uid;
-                       ctladdr->q_gid = st.st_gid;
-                       ctladdr->q_flags |= QGOODUID;
+                       if (tTd(27, 4))
+                               printf("include: open: %s\n", errstring(rval));

                }
        }
                }
        }

-

        clrevent(ev);
 
 resetuid:
        clrevent(ev);
 
 resetuid:


@@ -761,9 +886,58 @@ resetuid:
        if (tTd(27, 9))
                printf("include: reset uid = %d/%d\n", getuid(), geteuid());
 
        if (tTd(27, 9))
                printf("include: reset uid = %d/%d\n", getuid(), geteuid());
 

+       if (rval == EOPENTIMEOUT)
+               usrerr("451 open timeout on %s", fname);
+

        if (fp == NULL)
                return rval;
 
        if (fp == NULL)
                return rval;
 

+       if (fstat(fileno(fp), &st) < 0)
+       {
+               rval = errno;
+               syserr("Cannot fstat %s!", fname);
+               return rval;
+       }
+
+#ifndef safechown
+       safechown = chownsafe(fileno(fp));
+#endif
+       if (ca == NULL && safechown)
+       {
+               ctladdr->q_uid = st.st_uid;
+               ctladdr->q_gid = st.st_gid;
+               ctladdr->q_flags |= QGOODUID;
+       }
+       if (ca != NULL && ca->q_uid == st.st_uid)
+       {
+               /* optimization -- avoid getpwuid if we already have info */
+               ctladdr->q_flags |= ca->q_flags & QBOGUSSHELL;
+               ctladdr->q_ruser = ca->q_ruser;
+       }
+       else
+       {
+               char *sh;
+               register struct passwd *pw;
+
+               sh = "/SENDMAIL/ANY/SHELL/";
+               pw = getpwuid(st.st_uid);
+               if (pw != NULL)
+               {
+                       ctladdr->q_ruser = newstr(pw->pw_name);
+                       if (safechown)
+                               sh = pw->pw_shell;
+               }
+               if (pw == NULL)
+                       ctladdr->q_flags |= QBOGUSSHELL;
+               else if(!usershellok(sh))
+               {
+                       if (safechown)
+                               ctladdr->q_flags |= QBOGUSSHELL;
+                       else
+                               ctladdr->q_flags |= QUNSAFEADDR;
+               }
+       }
+

        if (bitset(EF_VRFYONLY, e->e_flags))
        {
                /* don't do any more now */
        if (bitset(EF_VRFYONLY, e->e_flags))
        {
                /* don't do any more now */


@@ -773,6 +947,19 @@ resetuid:
                return rval;
        }
 
                return rval;
        }
 

+       /*
+       ** Check to see if some bad guy can write this file
+       **
+       **      This should really do something clever with group
+       **      permissions; currently we just view world writable
+       **      as unsafe.  Also, we don't check for writable
+       **      directories in the path.  We've got to leave
+       **      something for the local sysad to do.
+       */
+
+       if (bitset(S_IWOTH, st.st_mode))
+               ctladdr->q_flags |= QUNSAFEADDR;
+

        /* read the file -- each line is a comma-separated list. */
        FileName = fname;
        LineNumber = 0;
        /* read the file -- each line is a comma-separated list. */
        FileName = fname;
        LineNumber = 0;


@@ -793,7 +980,8 @@ resetuid:
 #ifdef LOG
                if (forwarding && LogLevel > 9)
                        syslog(LOG_INFO, "%s: forward %s => %s",
 #ifdef LOG
                if (forwarding && LogLevel > 9)
                        syslog(LOG_INFO, "%s: forward %s => %s",

-                               e->e_id, oldto, buf);
+                               e->e_id == NULL ? "NOQUEUE" : e->e_id,
+                               oldto, buf);

 #endif
 
                AliasLevel++;
 #endif
 
                AliasLevel++;