From: Joerg Jaspert Date: Mon, 12 May 2008 22:12:56 +0000 (+0200) Subject: First version of a check for ssh keys X-Git-Tag: userdir-ldap-0.3.22~1^2~2 X-Git-Url: https://git.adam-barratt.org.uk/?p=mirror%2Fuserdir-ldap.git;a=commitdiff_plain;h=0159c3e12f39119617f4c93319a1500284f8958a;hp=-c First version of a check for ssh keys --- 0159c3e12f39119617f4c93319a1500284f8958a diff --combined ud-mailgate index f705497,cf82b56..94a4a71 --- a/ud-mailgate +++ b/ud-mailgate @@@ -1,13 -1,9 +1,14 @@@ #!/usr/bin/env python # -*- mode: python -*- -import userdir_gpg, userdir_ldap, sys, traceback, time, ldap, os; -import pwd -from userdir_gpg import *; -from userdir_ldap import *; + +# Prior copyright probably rmurray, troup, joey, jgg -- weasel 2008 +# Copyright (c) 2008 Peter Palfrader ++# Copyright (c) 2008 Joerg Jaspert + - import userdir_gpg, userdir_ldap, sys, traceback, time, ldap, os; - import pwd - from userdir_gpg import *; - from userdir_ldap import *; ++import userdir_gpg, userdir_ldap, sys, traceback, time, ldap, os, commands ++import pwd, tmpfile ++from userdir_gpg import * ++from userdir_ldap import * # Error codes from /usr/include/sysexits.h ReplyTo = ConfModule.replyto; @@@ -15,6 -11,6 +16,7 @@@ PingFrom = ConfModule.pingfrom ChPassFrom = ConfModule.chpassfrom; ChangeFrom = ConfModule.changefrom; ReplayCacheFile = ConfModule.replaycachefile; ++SSHFingerprintFile = ConfModule.fingerprintfile EX_TEMPFAIL = 75; EX_PERMFAIL = 65; # EX_DATAERR @@@ -27,6 -23,6 +29,8 @@@ mailWhitelist = { SeenList = {} DNS = {} ++SSHFingerprint = re.compile('^(\d+) ([0-9a-f\:]{47}) (.+)$') ++ ArbChanges = {"c": "..", "l": ".*", "facsimileTelephoneNumber": ".*", @@@ -44,7 -40,6 +48,7 @@@ "mailDisableMessage": ".*", "mailGreylisting": "^(TRUE|FALSE)$", "mailCallout": "^(TRUE|FALSE)$", + "VoIP": ".*", }; DelItems = {"c": None, @@@ -72,7 -67,6 +76,7 @@@ "mailRHSBL": None, "mailWhitelist": None, "mailDisableMessage": None, + "VoIP": None, }; # Decode a GPS location from some common forms @@@ -218,16 -212,16 +222,46 @@@ def DoPosition(Str,Attrs) Attrs.append((ldap.MOD_REPLACE,"longitude",sLong)); return "Position set to %s/%s (%s/%s decimal degrees)"%(sLat,sLong,Lat,Long); ++# Load bad ssh fingerprints ++def LoadBadSSH(): ++ f = open(SSHFingerprintFile, "r") ++ bad = [] ++ FingerprintLine = re.compile('^([0-9a-f\:]{47}).*$') ++ for line in f.readlines(): ++ Match = FingerprintLine.match(line) ++ if Match is not None: ++ g = Match.groups() ++ bad.append(g[0]) ++ return bad ++ # Handle an SSH authentication key, the line format is: # [options] 1024 35 13188913666680[..] [comment] --def DoSSH(Str,Attrs): ++def DoSSH(Str,Attrs, badkeys): Match = SSH2AuthSplit.match(Str); if Match == None: Match = re.compile('^1024 (\d+) ').match(Str) if Match is not None: return "SSH1 keys not supported anymore" return None; -- ++ ++ (fd, path) = tempfile.mkstemp("", "sshkeytry") ++ f = open(path, "w") ++ f.write(Str) ++ f.close ++ (result, output) = commands.getstatusoutput("ssh-keygen -f %s -l" % (path)) ++ os.remove(path) ++ if (result != 0): ++ sys.stderr.write("ssh-keygen -l invocation failed!\n%s\n" % (output)) ++ sys.exit(result) ++ ++ Match = SSHFingerprint.match(output) ++ ++ g = Match.groups() ++ if (g[0] < 1024): ++ return "SSH keys must have at least 1024 bits, not added" ++ elif g[0] in badkeys: ++ return "Submitted SSH Key known to be bad and insecure, not added" ++ global SeenKey; if SeenKey: Attrs.append((ldap.MOD_ADD,"sshRSAAuthKey",Str)); @@@ -238,28 -232,17 +272,28 @@@ return "SSH Keys replaced with "+FormatSSHAuth(Str); # Handle changing a dns entry -# host in a 12.12.12.12 -# host in cname foo.bar. <- Trailing dot is required +# host IN A 12.12.12.12 +# host IN AAAA 1234::5678 +# host IN CNAME foo.bar. <- Trailing dot is required +# host IN MX foo.bar. <- Trailing dot is required def DoDNS(Str,Attrs,DnRecord): - cname = re.match("^[-\w]+\s+in\s+cname\s+[-\w.]+\.$",Str,re.IGNORECASE); - if re.match('^[-\w]+\s+in\s+a\s+\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3}$',\ - Str,re.IGNORECASE) == None and cname == None and \ - re.match("^[-\w]+\s+in\s+mx\s+\d{1,3}\s+[-\w.]+\.$",Str,re.IGNORECASE) == None: - return None; + cnamerecord = re.match("^[-\w]+\s+IN\s+CNAME\s+([-\w.]+\.)$",Str,re.IGNORECASE) + arecord = re.match('^[-\w]+\s+IN\s+A\s+(\d{1,3}\.\d{1,3}\.\d{1,3}\.\d{1,3})$',Str,re.IGNORECASE) + mxrecord = re.match("^[-\w]+\s+IN\s+MX\s+(\d{1,3})\s+([-\w.]+\.)$",Str,re.IGNORECASE) + #aaaarecord = re.match('^[-\w]+\s+IN\s+AAAA\s+((?:[0-9a-f]{1,4})(?::[0-9a-f]{1,4})*(?::(?:(?::[0-9a-f]{1,4})*|:))?)$',Str,re.IGNORECASE) + aaaarecord = re.match('^[-\w]+\s+IN\s+AAAA\s+([A-F0-9:]{2,39})$',Str,re.IGNORECASE) + + if cnamerecord == None and\ + arecord == None and\ + mxrecord == None and\ + aaaarecord == None: + return None; # Check if the name is already taken - G = re.match('^([-\w+]+)\s',Str).groups(); + G = re.match('^([-\w+]+)\s',Str) + if G == None: + raise Error, "Hostname not found although we already passed record syntax checks" + hostname = G.group(1) # Check for collisions global l; @@@ -267,7 -250,7 +301,7 @@@ # since we accept either. It'd probably be better to parse the # incoming string in order to construct what we feed LDAP rather # than just passing it through as is.] - filter = "(|(dnsZoneEntry=%s *)(dnsZoneEntry=%s *))" % (G[0], G[0]) + filter = "(|(dnsZoneEntry=%s *)(dnsZoneEntry=%s *))" % (hostname, hostname) Rec = l.search_s(BaseDn,ldap.SCOPE_ONELEVEL,filter,["uid"]); for x in Rec: if GetAttr(x,"uid") != GetAttr(DnRecord,"uid"): @@@ -276,59 -259,24 +310,59 @@@ global SeenDNS; global DNS; - if cname: - if DNS.has_key(G[0]): + if cnamerecord: + if DNS.has_key(hostname): return "CNAME and other RR types not allowed: "+Str else: - DNS[G[0]] = 2 + DNS[hostname] = 2 else: - if DNS.has_key(G[0]) and DNS[G[0]] == 2: + if DNS.has_key(hostname) and DNS[hostname] == 2: return "CNAME and other RR types not allowed: "+Str else: - DNS[G[0]] = 1 - + DNS[hostname] = 1 + + if cnamerecord != None: + sanitized = "%s IN CNAME %s" % (hostname, cnamerecord.group(1)) + elif arecord != None: + ipaddress = arecord.group(1) + for quad in ipaddress.split('.'): + if not (int(quad) >=0 and int(quad) <= 255): + return "Invalid quad %s in IP address %s in line %s" %(quad, ipaddress, Str) + sanitized = "%s IN A %s"% (hostname, ipaddress) + elif mxrecord != None: + priority = mxrecord.group(1) + mx = mxrecord.group(2) + sanitized = "%s IN MX %s %s" % (hostname, priority, mx) + elif aaaarecord != None: + ipv6address = aaaarecord.group(1) + parts = ipv6address.split(':') + if len(parts) > 8: + return "Invalid IPv6 address (%s): too many parts"%(ipv6address) + if len(parts) <= 2: + return "Invalid IPv6 address (%s): too few parts"%(ipv6address) + if parts[0] == "": + parts.pop(0) + if parts[-1] == "": + parts.pop(-1) + seenEmptypart = False + for p in parts: + if len(p) > 4: + return "Invalid IPv6 address (%s): part %s is longer than 4 characters"%(ipv6address, p) + if p == "": + if seenEmptypart: + return "Invalid IPv6 address (%s): more than one :: (nothing in between colons) is not allowed"%(ipv6address) + seenEmptypart = True + sanitized = "%s IN AAAA %s" % (hostname, ipv6address) + else: + raise Error, "None of the types I recognize was it. I shouldn't be here. confused." + if SeenDNS: - Attrs.append((ldap.MOD_ADD,"dnsZoneEntry",Str)); - return "DNS Entry added "+Str; - - Attrs.append((ldap.MOD_REPLACE,"dnsZoneEntry",Str)); + Attrs.append((ldap.MOD_ADD,"dnsZoneEntry",sanitized)); + return "DNS Entry added "+sanitized; + + Attrs.append((ldap.MOD_REPLACE,"dnsZoneEntry",sanitized)); SeenDNS = 1; - return "DNS Entry replaced with "+Str; + return "DNS Entry replaced with "+sanitized; # Handle an RBL list (mailRBL, mailRHSBL, mailWhitelist) def DoRBL(Str,Attrs): @@@ -371,11 -319,11 +405,12 @@@ def HandleChange(Reply,DnRecord,Key) try: if Line == "show": Show = 1; -- Res = "OK"; ++ Res = "OK"; else: -- Res = DoPosition(Line,Attrs) or DoDNS(Line,Attrs,DnRecord) or \ -- DoArbChange(Line,Attrs) or DoSSH(Line,Attrs) or \ -- DoDel(Line,Attrs) or DoRBL(Line,Attrs); ++ badkeys = LoadBadSSH() ++ Res = DoPosition(Line,Attrs) or DoDNS(Line,Attrs,DnRecord) or \ ++ DoArbChange(Line,Attrs) or DoSSH(Line,Attrs,badkeys) or \ ++ DoDel(Line,Attrs) or DoRBL(Line,Attrs) except: Res = None; Result = Result + "==> %s: %s\n" %(sys.exc_type,sys.exc_value); diff --combined userdir-ldap.conf index 048e907,048e907..d3a37bb --- a/userdir-ldap.conf +++ b/userdir-ldap.conf @@@ -24,6 -24,6 +24,7 @@@ changefrom = "change@" + maildomain templatesdir = "/etc/userdir-ldap/templates/"; replaycachefile = "/var/cache/userdir-ldap/mail/replay"; #replaycachefile = "/tmp/replay"; ++fingerprintfile = "/etc/userdir-ldap/badfingerprints" # Echelon ech_errorlog = "/org/db.debian.org/mail/Log/ech-errors.log"