Annotation of src/etc/security, Revision 1.10
1.1 deraadt 1: #!/bin/sh -
2: #
1.10 ! bitblt 3: # $OpenBSD: security,v 1.9 1996/09/16 19:40:27 deraadt Exp $
1.1 deraadt 4: #
5: PATH=/sbin:/usr/sbin:/bin:/usr/bin
6:
7: umask 077
8:
1.7 deraadt 9: DIR=/tmp/_secure$$
10: ERR=$DIR/_secure1
11: TMP1=$DIR/_secure2
12: TMP2=$DIR/_secure3
13: TMP3=$DIR/_secure4
14: LIST=$DIR/_secure5
15: OUTPUT=$DIR/_secure6
1.1 deraadt 16:
1.7 deraadt 17:
18: if ! mkdir $DIR ; then
19: printf "tmp directory %s already exists, looks like:\n" $DIR
20: ls -alF $DIR
21: exit 1
22: fi
1.8 deraadt 23:
24: trap 'rm -rf $DIR' 0
1.1 deraadt 25:
26: # Check the master password file syntax.
27: MP=/etc/master.passwd
28: awk -F: '{
29: if ($0 ~ /^[ ]*$/) {
30: printf("Line %d is a blank line.\n", NR);
31: next;
32: }
33: if (NF != 10)
34: printf("Line %d has the wrong number of fields.\n", NR);
1.2 deraadt 35: if ($1 ~ /^[+-].*$/)
36: next;
37: if ($1 == "")
38: printf("Line %d has an empty login field.\n",NR);
39: else if ($1 !~ /^[A-Za-z0-9][A-Za-z0-9_-]*$/)
1.1 deraadt 40: printf("Login %s has non-alphanumeric characters.\n", $1);
41: if (length($1) > 8)
42: printf("Login %s has more than 8 characters.\n", $1);
43: if ($2 == "")
44: printf("Login %s has no password.\n", $1);
45: if (length($2) != 13 && ($10 ~ /.*sh$/ || $10 == ""))
46: printf("Login %s is off but still has a valid shell.\n", $1);
1.9 deraadt 47: if ($3 == 0 && $1 != "root")
1.1 deraadt 48: printf("Login %s has a user id of 0.\n", $1);
49: if ($3 < 0)
50: printf("Login %s has a negative user id.\n", $1);
51: if ($4 < 0)
52: printf("Login %s has a negative group id.\n", $1);
53: }' < $MP > $OUTPUT
54: if [ -s $OUTPUT ] ; then
55: printf "\nChecking the $MP file:\n"
56: cat $OUTPUT
57: fi
58:
59: awk -F: '{ print $1 }' $MP | sort | uniq -d > $OUTPUT
60: if [ -s $OUTPUT ] ; then
61: printf "\n$MP has duplicate user names.\n"
62: column $OUTPUT
63: fi
64:
1.9 deraadt 65: awk -F: '{ print $1 " " $3 }' $MP | sort -n +1 | tee $TMP1 |
1.1 deraadt 66: uniq -d -f 1 | awk '{ print $2 }' > $TMP2
67: if [ -s $TMP2 ] ; then
68: printf "\n$MP has duplicate user id's.\n"
69: while read uid; do
70: grep -w $uid $TMP1
71: done < $TMP2 | column
72: fi
73:
74: # Backup the master password file; a special case, the normal backup
75: # mechanisms also print out file differences and we don't want to do
76: # that because this file has encrypted passwords in it.
1.2 deraadt 77: if [ ! -d /var/backups ] ; then
78: mkdir /var/backups
79: chmod 755 /var/backups
80: fi
1.1 deraadt 81: CUR=/var/backups/`basename $MP`.current
82: BACK=/var/backups/`basename $MP`.backup
83: if [ -s $CUR ] ; then
84: if cmp -s $CUR $MP; then
85: :
86: else
87: cp -p $CUR $BACK
88: cp -p $MP $CUR
89: chown root.wheel $CUR
90: fi
91: else
92: cp -p $MP $CUR
93: chown root.wheel $CUR
94: fi
95:
96: # Check the group file syntax.
97: GRP=/etc/group
98: awk -F: '{
99: if ($0 ~ /^[ ]*$/) {
100: printf("Line %d is a blank line.\n", NR);
101: next;
102: }
1.2 deraadt 103: if ($1 ~ /^[+-].*$/)
104: next;
1.1 deraadt 105: if (NF != 4)
106: printf("Line %d has the wrong number of fields.\n", NR);
107: if ($1 !~ /^[A-za-z0-9]*$/)
108: printf("Group %s has non-alphanumeric characters.\n", $1);
109: if (length($1) > 8)
110: printf("Group %s has more than 8 characters.\n", $1);
111: if ($3 !~ /[0-9]*/)
112: printf("Login %s has a negative group id.\n", $1);
113: }' < $GRP > $OUTPUT
114: if [ -s $OUTPUT ] ; then
115: printf "\nChecking the $GRP file:\n"
116: cat $OUTPUT
117: fi
118:
119: awk -F: '{ print $1 }' $GRP | sort | uniq -d > $OUTPUT
120: if [ -s $OUTPUT ] ; then
121: printf "\n$GRP has duplicate group names.\n"
122: column $OUTPUT
123: fi
124:
125: # Check for root paths, umask values in startup files.
126: # The check for the root paths is problematical -- it's likely to fail
127: # in other environments. Once the shells have been modified to warn
128: # of '.' in the path, the path tests should go away.
129: > $OUTPUT
130: rhome=/root
131: umaskset=no
132: list="/etc/csh.cshrc /etc/csh.login ${rhome}/.cshrc ${rhome}/.login"
133: for i in $list ; do
134: if [ -f $i ] ; then
135: if egrep umask $i > /dev/null ; then
136: umaskset=yes
137: fi
138: egrep umask $i |
139: awk '$2 % 100 < 20 \
140: { print "Root umask is group writeable" }
141: $2 % 10 < 2 \
142: { print "Root umask is other writeable" }' >> $OUTPUT
143: /bin/csh -f -s << end-of-csh > /dev/null 2>&1
144: unset path
145: source $i
146: /bin/ls -ldgT \$path > $TMP1
147: end-of-csh
148: awk '{
149: if ($10 ~ /^\.$/) {
150: print "The root path includes .";
151: next;
152: }
153: }
154: $1 ~ /^d....w/ \
155: { print "Root path directory " $10 " is group writeable." } \
156: $1 ~ /^d.......w/ \
157: { print "Root path directory " $10 " is other writeable." }' \
158: < $TMP1 >> $OUTPUT
159: fi
160: done
161: if [ $umaskset = "no" -o -s $OUTPUT ] ; then
162: printf "\nChecking root csh paths, umask values:\n$list\n"
163: if [ -s $OUTPUT ]; then
164: cat $OUTPUT
165: fi
166: if [ $umaskset = "no" ] ; then
167: printf "\nRoot csh startup files do not set the umask.\n"
168: fi
169: fi
170:
171: > $OUTPUT
172: rhome=/root
173: umaskset=no
174: list="${rhome}/.profile"
175: for i in $list; do
176: if [ -f $i ] ; then
177: if egrep umask $i > /dev/null ; then
178: umaskset=yes
179: fi
180: egrep umask $i |
181: awk '$2 % 100 < 20 \
182: { print "Root umask is group writeable" } \
183: $2 % 10 < 2 \
184: { print "Root umask is other writeable" }' >> $OUTPUT
185: /bin/sh << end-of-sh > /dev/null 2>&1
186: PATH=
187: . $i
188: list=\`echo \$PATH | /usr/bin/sed -e 's/:/ /g'\`
189: /bin/ls -ldgT \$list > $TMP1
190: end-of-sh
191: awk '{
192: if ($10 ~ /^\.$/) {
193: print "The root path includes .";
194: next;
195: }
196: }
197: $1 ~ /^d....w/ \
198: { print "Root path directory " $10 " is group writeable." } \
199: $1 ~ /^d.......w/ \
200: { print "Root path directory " $10 " is other writeable." }' \
201: < $TMP1 >> $OUTPUT
202:
203: fi
204: done
205: if [ $umaskset = "no" -o -s $OUTPUT ] ; then
206: printf "\nChecking root sh paths, umask values:\n$list\n"
207: if [ -s $OUTPUT ]; then
208: cat $OUTPUT
209: fi
210: if [ $umaskset = "no" ] ; then
211: printf "\nRoot sh startup files do not set the umask.\n"
212: fi
213: fi
214:
215: # Root and uucp should both be in /etc/ftpusers.
216: if egrep root /etc/ftpusers > /dev/null ; then
217: :
218: else
219: printf "\nRoot not listed in /etc/ftpusers file.\n"
220: fi
221: if egrep uucp /etc/ftpusers > /dev/null ; then
222: :
223: else
224: printf "\nUucp not listed in /etc/ftpusers file.\n"
225: fi
226:
227: # Uudecode should not be in the /etc/aliases file.
228: if egrep 'uudecode|decode' /etc/aliases; then
229: printf "\nThere is an entry for uudecode in the /etc/aliases file.\n"
230: fi
231:
232: # Files that should not have + signs.
1.2 deraadt 233: list="/etc/hosts.equiv /etc/shosts.equiv /etc/hosts.lpd"
1.1 deraadt 234: for f in $list ; do
1.6 millert 235: if [ -s $f ] ; then
1.2 deraadt 236: awk '{
1.6 millert 237: if ($0 ~ /^\+@.*$/ )
1.2 deraadt 238: next;
1.6 millert 239: if ($0 ~ /^\+.*$/ )
1.2 deraadt 240: printf("\nPlus sign in %s file.\n", FILENAME);
241: }' $f
1.1 deraadt 242: fi
243: done
244:
1.9 deraadt 245: # Check for special users with .rhosts/.shosts files. Only root should
246: # have .rhosts/.shosts files. Also, .rhosts/.shosts files
1.2 deraadt 247: # should not have plus signs.
1.9 deraadt 248: awk -F: '$1 != "root" && $1 !~ /^[+-].*$/ && \
1.1 deraadt 249: ($3 < 100 || $1 == "ftp" || $1 == "uucp") \
250: { print $1 " " $6 }' /etc/passwd |
251: while read uid homedir; do
1.2 deraadt 252: for j in .rhosts .shosts; do
253: if [ -f ${homedir}/$j ] ; then
254: rhost=`ls -ldgT ${homedir}/$j`
255: printf "$uid: $rhost\n"
256: fi
257: done
1.1 deraadt 258: done > $OUTPUT
259: if [ -s $OUTPUT ] ; then
1.2 deraadt 260: printf "\nChecking for special users with .rhosts/.shosts files.\n"
1.1 deraadt 261: cat $OUTPUT
262: fi
263:
264: awk -F: '{ print $1 " " $6 }' /etc/passwd | \
265: while read uid homedir; do
1.2 deraadt 266: for j in .rhosts .shosts; do
267: if [ -f ${homedir}/$j ] ; then
268: awk '{
269: if ($0 ~ /^+@.*$/ )
270: next;
1.4 deraadt 271: if ($0 ~ /^\+[ ]*$/ )
1.2 deraadt 272: printf("%s has + sign in it.\n",
273: FILENAME);
274: }' ${homedir}/$j
275: fi
276: done
1.1 deraadt 277: done > $OUTPUT
278: if [ -s $OUTPUT ] ; then
1.2 deraadt 279: printf "\nChecking .rhosts/.shosts files syntax.\n"
1.1 deraadt 280: cat $OUTPUT
281: fi
282:
283: # Check home directories. Directories should not be owned by someone else
284: # or writeable.
1.2 deraadt 285: awk -F: '{ if ( $1 !~ /^[+-].*$/ ) print $1 " " $6 }' /etc/passwd | \
1.1 deraadt 286: while read uid homedir; do
287: if [ -d ${homedir}/ ] ; then
288: file=`ls -ldgT ${homedir}`
289: printf "$uid $file\n"
290: fi
291: done |
292: awk '$1 != $4 && $4 != "root" \
293: { print "user " $1 " home directory is owned by " $4 }
294: $2 ~ /^-....w/ \
295: { print "user " $1 " home directory is group writeable" }
296: $2 ~ /^-.......w/ \
297: { print "user " $1 " home directory is other writeable" }' > $OUTPUT
298: if [ -s $OUTPUT ] ; then
299: printf "\nChecking home directories.\n"
300: cat $OUTPUT
301: fi
302:
303: # Files that should not be owned by someone else or readable.
1.2 deraadt 304: list=".netrc .rhosts .shosts"
1.1 deraadt 305: awk -F: '{ print $1 " " $6 }' /etc/passwd | \
306: while read uid homedir; do
307: for f in $list ; do
308: file=${homedir}/${f}
309: if [ -f $file ] ; then
310: printf "$uid $f `ls -ldgT $file`\n"
311: fi
312: done
313: done |
314: awk '$1 != $5 && $5 != "root" \
315: { print "user " $1 " " $2 " file is owned by " $5 }
316: $3 ~ /^-......r/ \
317: { print "user " $1 " " $2 " file is other readable" }
318: $3 ~ /^-....w/ \
319: { print "user " $1 " " $2 " file is group writeable" }
320: $3 ~ /^-.......w/ \
321: { print "user " $1 " " $2 " file is other writeable" }' > $OUTPUT
322:
323: # Files that should not be owned by someone else or writeable.
324: list=".bashrc .cshrc .emacs .exrc .forward .klogin .login .logout \
325: .profile .tcshrc"
326: awk -F: '{ print $1 " " $6 }' /etc/passwd | \
327: while read uid homedir; do
328: for f in $list ; do
329: file=${homedir}/${f}
330: if [ -f $file ] ; then
331: printf "$uid $f `ls -ldgT $file`\n"
332: fi
333: done
334: done |
335: awk '$1 != $5 && $5 != "root" \
336: { print "user " $1 " " $2 " file is owned by " $5 }
337: $3 ~ /^-....w/ \
338: { print "user " $1 " " $2 " file is group writeable" }
339: $3 ~ /^-.......w/ \
340: { print "user " $1 " " $2 " file is other writeable" }' >> $OUTPUT
341: if [ -s $OUTPUT ] ; then
342: printf "\nChecking dot files.\n"
343: cat $OUTPUT
344: fi
345:
346: # Mailboxes should be owned by user and unreadable.
347: ls -l /var/mail | sed 1d | \
348: awk '$3 != $9 \
349: { print "user " $9 " mailbox is owned by " $3 }
350: $1 != "-rw-------" \
351: { print "user " $9 " mailbox is " $1 ", group " $4 }' > $OUTPUT
352: if [ -s $OUTPUT ] ; then
353: printf "\nChecking mailbox ownership.\n"
354: cat $OUTPUT
355: fi
356:
1.2 deraadt 357: if [ -f /etc/exports ]; then
358: # File systems should not be globally exported.
359: awk '{
1.1 deraadt 360: readonly = 0;
361: for (i = 2; i <= NF; ++i) {
362: if ($i ~ /-ro/)
363: readonly = 1;
364: else if ($i !~ /^-/)
365: next;
366: }
367: if (readonly)
368: print "File system " $1 " globally exported, read-only."
369: else
370: print "File system " $1 " globally exported, read-write."
1.2 deraadt 371: }' < /etc/exports > $OUTPUT
372: if [ -s $OUTPUT ] ; then
1.1 deraadt 373: printf "\nChecking for globally exported file systems.\n"
374: cat $OUTPUT
1.2 deraadt 375: fi
1.1 deraadt 376: fi
377:
1.5 deraadt 378: # Display any changes in setuid/setgid files and devices.
379: pending="\nChecking setuid/setgid files and devices:\n"
1.1 deraadt 380: (find / \( ! -fstype local -o -fstype fdesc -o -fstype kernfs \
381: -o -fstype procfs \) -a -prune -o \
1.2 deraadt 382: -type f -a \( -perm -u+s -o -perm -g+s \) -print -o \
1.10 ! bitblt 383: ! -type d -a ! -type f -a ! -type l -a ! -type s -ls | \
! 384: sort > $LIST) 2> $OUTPUT
1.1 deraadt 385:
386: # Display any errors that occurred during system file walk.
387: if [ -s $OUTPUT ] ; then
1.2 deraadt 388: printf "${pending}Setuid/device find errors:\n"
389: pending=
1.1 deraadt 390: cat $OUTPUT
391: printf "\n"
392: fi
393:
394: # Display any changes in the setuid file list.
395: egrep -v '^[bc]' $LIST > $TMP1
396: if [ -s $TMP1 ] ; then
397: # Check to make sure uudecode isn't setuid.
398: if grep -w uudecode $TMP1 > /dev/null ; then
1.2 deraadt 399: printf "${pending}\nUudecode is setuid.\n"
400: pending=
1.1 deraadt 401: fi
402:
403: CUR=/var/backups/setuid.current
404: BACK=/var/backups/setuid.backup
405:
406: if [ -s $CUR ] ; then
407: if cmp -s $CUR $TMP1 ; then
408: :
409: else
410: > $TMP2
411: join -110 -210 -v2 $CUR $TMP1 > $OUTPUT
412: if [ -s $OUTPUT ] ; then
1.2 deraadt 413: printf "${pending}Setuid additions:\n"
414: pending=
1.1 deraadt 415: tee -a $TMP2 < $OUTPUT
416: printf "\n"
417: fi
418:
419: join -110 -210 -v1 $CUR $TMP1 > $OUTPUT
420: if [ -s $OUTPUT ] ; then
1.2 deraadt 421: printf "${pending}Setuid deletions:\n"
422: pending=
1.1 deraadt 423: tee -a $TMP2 < $OUTPUT
424: printf "\n"
425: fi
426:
427: sort +9 $TMP2 $CUR $TMP1 | \
428: sed -e 's/[ ][ ]*/ /g' | uniq -u > $OUTPUT
429: if [ -s $OUTPUT ] ; then
1.2 deraadt 430: printf "${pending}Setuid changes:\n"
431: pending=
1.1 deraadt 432: column -t $OUTPUT
433: printf "\n"
434: fi
435:
436: cp $CUR $BACK
437: cp $TMP1 $CUR
438: fi
439: else
1.2 deraadt 440: printf "${pending}Setuid additions:\n"
441: pending=
1.1 deraadt 442: column -t $TMP1
443: printf "\n"
444: cp $TMP1 $CUR
445: fi
446: fi
447:
448: # Check for block and character disk devices that are readable or writeable
449: # or not owned by root.operator.
450: >$TMP1
1.2 deraadt 451: DISKLIST="dk fd hd hk hp jb kra ra rb rd rl rx xd rz sd up wd vnd ccd"
1.1 deraadt 452: for i in $DISKLIST; do
453: egrep "^b.*/${i}[0-9][0-9]*[a-h]$" $LIST >> $TMP1
454: egrep "^c.*/r${i}[0-9][0-9]*[a-h]$" $LIST >> $TMP1
455: done
456:
457: awk '$3 != "root" || $4 != "operator" || $1 !~ /.rw-r-----/ \
458: { printf("Disk %s is user %s, group %s, permissions %s.\n", \
459: $11, $3, $4, $1); }' < $TMP1 > $OUTPUT
460: if [ -s $OUTPUT ] ; then
461: printf "\nChecking disk ownership and permissions.\n"
462: cat $OUTPUT
463: printf "\n"
464: fi
465:
466: # Display any changes in the device file list.
467: egrep '^[bc]' $LIST | sort +10 > $TMP1
468: if [ -s $TMP1 ] ; then
469: CUR=/var/backups/device.current
470: BACK=/var/backups/device.backup
471:
472: if [ -s $CUR ] ; then
473: if cmp -s $CUR $TMP1 ; then
474: :
475: else
476: > $TMP2
477: join -111 -211 -v2 $CUR $TMP1 > $OUTPUT
478: if [ -s $OUTPUT ] ; then
479: printf "Device additions:\n"
480: tee -a $TMP2 < $OUTPUT
481: printf "\n"
482: fi
483:
484: join -111 -211 -v1 $CUR $TMP1 > $OUTPUT
485: if [ -s $OUTPUT ] ; then
486: printf "Device deletions:\n"
487: tee -a $TMP2 < $OUTPUT
488: printf "\n"
489: fi
490:
491: # Report any block device change. Ignore character
492: # devices, only the name is significant.
493: cat $TMP2 $CUR $TMP1 | \
494: sed -e '/^c/d' | \
495: sort +10 | \
496: sed -e 's/[ ][ ]*/ /g' | \
497: uniq -u > $OUTPUT
498: if [ -s $OUTPUT ] ; then
499: printf "Block device changes:\n"
500: column -t $OUTPUT
501: printf "\n"
502: fi
503:
504: cp $CUR $BACK
505: cp $TMP1 $CUR
506: fi
507: else
508: printf "Device additions:\n"
509: column -t $TMP1
510: printf "\n"
511: cp $TMP1 $CUR
512: fi
513: fi
514:
515: # Check special files.
516: # Check system binaries.
517: #
518: # Create the mtree tree specifications using:
519: #
520: # mtree -cx -pDIR -kcksum,gid,mode,nlink,size,link,time,uid > DIR.secure
1.2 deraadt 521: # chown root.wheel DIR.secure
522: # chmod 600 DIR.secure
1.1 deraadt 523: #
524: # Note, this is not complete protection against Trojan horsed binaries, as
525: # the hacker can modify the tree specification to match the replaced binary.
526: # For details on really protecting yourself against modified binaries, see
527: # the mtree(8) manual page.
1.2 deraadt 528: if [ -d /etc/mtree ]; then
529: cd /etc/mtree
1.1 deraadt 530: mtree -e -p / -f /etc/mtree/special > $OUTPUT
531: if [ -s $OUTPUT ] ; then
532: printf "\nChecking special files and directories.\n"
533: cat $OUTPUT
534: fi
535:
536: > $OUTPUT
537: for file in *.secure; do
1.2 deraadt 538: [ $file = '*.secure' ] && continue
1.1 deraadt 539: tree=`sed -n -e '3s/.* //p' -e 3q $file`
540: mtree -f $file -p $tree > $TMP1
541: if [ -s $TMP1 ]; then
542: printf "\nChecking $tree:\n" >> $OUTPUT
543: cat $TMP1 >> $OUTPUT
544: fi
545: done
546: if [ -s $OUTPUT ] ; then
547: printf "\nChecking system binaries:\n"
548: cat $OUTPUT
549: fi
1.2 deraadt 550: else
551: echo /etc/mtree is missing
1.1 deraadt 552: fi
553:
554: # List of files that get backed up and checked for any modifications. Each
555: # file is expected to have two backups, /var/backups/file.{current,backup}.
556: # Any changes cause the files to rotate.
557: if [ -s /etc/changelist ] ; then
558: for file in `cat /etc/changelist`; do
559: CUR=/var/backups/`basename $file`.current
560: BACK=/var/backups/`basename $file`.backup
561: if [ -s $file ]; then
562: if [ -s $CUR ] ; then
563: diff $CUR $file > $OUTPUT
564: if [ -s $OUTPUT ] ; then
565: printf "\n======\n%s diffs (OLD < > NEW)\n======\n" $file
566: cat $OUTPUT
567: cp -p $CUR $BACK
568: cp -p $file $CUR
569: chown root.wheel $CUR $BACK
570: fi
571: else
572: cp -p $file $CUR
573: chown root.wheel $CUR
574: fi
575: fi
576: done
577: fi
![[BACK]](/icons/back.gif){kind=icon}
Return to security CVS log ![[TXT]](/icons/text.gif){kind=icon}
![[DIR]](/icons/dir.gif){kind=icon}
Up to [local] / src / etc