X-Git-Url: https://git.adam-barratt.org.uk/?p=mirror%2Fuserdir-ldap.git;a=blobdiff_plain;f=ud-mailgate;h=7edb3fd33b074752581d7f1b480c700babae4cb4;hp=8f9e0925876b7d3b11aa2dc041ab16f0bbe61eed;hb=f8181b0dfa59390433a8329e61f0cfbc2f720644;hpb=d5416c75fd5435530aa08379c4194894dff821e4 diff --git a/ud-mailgate b/ud-mailgate index 8f9e092..7edb3fd 100755 --- a/ud-mailgate +++ b/ud-mailgate @@ -3,12 +3,14 @@ # Prior copyright probably rmurray, troup, joey, jgg -- weasel 2008 # Copyright (c) 2009 Stephen Gran -# Copyright (c) 2008 Peter Palfrader +# Copyright (c) 2008,2009,2010 Peter Palfrader # Copyright (c) 2008 Joerg Jaspert # Copyright (c) 2010 Helmut Grohne import userdir_gpg, userdir_ldap, sys, traceback, time, ldap, os, commands import pwd, tempfile +import subprocess +import email, email.parser from userdir_gpg import * from userdir_ldap import * @@ -34,18 +36,17 @@ mailRHSBL = {} mailWhitelist = {} SeenList = {} DNS = {} -SudoPasswd = {} ValidHostNames = [] # will be initialized in later SSHFingerprint = re.compile('^(\d+) ([0-9a-f\:]{47}) (.+)$') SSHRSA1Match = re.compile('^^(.* )?\d+ \d+ \d+') -GenderTable = {"male": 1, - "1": 1, - "female": 2, - "2": 2, - "unspecified": 9, - "9": 9, +GenderTable = {"male": '1', + "1": '1', + "female": '2', + "2": '2', + "unspecified": '9', + "9": '9', }; ArbChanges = {"c": "..", @@ -322,10 +323,17 @@ def DoSSH(Str, Attrs, badkeys, uid): Match = SSHFingerprint.match(output) g = Match.groups() - if int(g[0]) < 1024: + if typekey == "ssh-rsa": + key_size_ok = (g[0]) >= 2048) + elif typekey == "ed25519": + key_size_ok = True + else: + key_size_ok = False + + if not key_size_ok: try: # Body - Subst["__ERROR__"] = "SSH keysize %s is below limit 1024" % (g[0]) + Subst["__ERROR__"] = "SSH key fails formal criteria. We only accept RSA keys (>= 2048 bits) or ed25519 keys." % (g[0]) ErrReply = TemplateSubst(Subst,open(TemplatesDir+"admin-info","r").read()) Child = os.popen("/usr/sbin/sendmail -t","w") @@ -337,7 +345,7 @@ def DoSSH(Str, Attrs, badkeys, uid): sys.exit(EX_TEMPFAIL) # And now break and stop processing input, which sends a reply to the user. - raise UDFormatError, "SSH keys must have at least 1024 bits, processing halted, NOTHING MODIFIED AT ALL" + raise UDFormatError, "SSH key fails formal criteria, NOTHING MODIFIED AT ALL" elif g[1] in badkeys: try: # Body @@ -355,14 +363,11 @@ def DoSSH(Str, Attrs, badkeys, uid): # And now break and stop processing input, which sends a reply to the user. raise UDFormatError, "Submitted SSH Key known to be bad and insecure, processing halted, NOTHING MODIFIED AT ALL" - if (typekey == "dss"): - return "DSA keys not accepted anymore" - global SeenKey; if SeenKey: Attrs.append((ldap.MOD_ADD,"sshRSAAuthKey",Str)); return "SSH Key added "+FormatSSHAuth(Str); - + Attrs.append((ldap.MOD_REPLACE,"sshRSAAuthKey",Str)); SeenKey = 1; return "SSH Keys replaced with "+FormatSSHAuth(Str); @@ -376,18 +381,20 @@ def DoDNS(Str,Attrs,DnRecord): cnamerecord = re.match("^[-\w]+\s+IN\s+CNAME\s+([-\w.]+\.)$",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) + txtrecord = re.match("^[-\w]+\s+IN\s+TXT\s+([-\d. a-z\t<>@]+)", 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: + if cnamerecord is None and\ + arecord is None and\ + mxrecord is None and\ + txtrecord is None and\ + aaaarecord is None: return None; # Check if the name is already taken G = re.match('^([-\w+]+)\s',Str) - if G == None: + if G is None: raise UDFormatError, "Hostname not found although we already passed record syntax checks" hostname = G.group(1) @@ -417,19 +424,21 @@ def DoDNS(Str,Attrs,DnRecord): else: DNS[hostname] = 1 - if cnamerecord != None: + if cnamerecord is not None: sanitized = "%s IN CNAME %s" % (hostname, cnamerecord.group(1)) - elif arecord != None: + elif txtrecord is not None: + sanitized = "%s IN TXT %s" % (hostname, txtrecord.group(1)) + elif arecord is not 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: + elif mxrecord is not None: priority = mxrecord.group(1) mx = mxrecord.group(2) sanitized = "%s IN MX %s %s" % (hostname, priority, mx) - elif aaaarecord != None: + elif aaaarecord is not None: ipv6address = aaaarecord.group(1) parts = ipv6address.split(':') if len(parts) > 8: @@ -484,8 +493,8 @@ def DoRBL(Str,Attrs): return "%s replaced with %s" % (Key,Host) # Handle a ConfirmSudoPassword request -def DoConfirmSudopassword(Str): - Match = re.compile('^confirm sudopassword ('+UUID_FORMAT+') ([a-z0-9.,*]+) ([0-9a-f]{40})$').match(Str) +def DoConfirmSudopassword(Str, SudoPasswd): + Match = re.compile('^confirm sudopassword ('+UUID_FORMAT+') ([a-z0-9.,*-]+) ([0-9a-f]{40})$').match(Str) if Match == None: return None @@ -493,14 +502,15 @@ def DoConfirmSudopassword(Str): hosts = Match.group(2) hmac = Match.group(3) - global SudoPasswd SudoPasswd[uuid] = (hosts, hmac) return "got confirm for sudo password %s on host(s) %s, auth code %s" % (uuid,hosts, hmac) -def FinishConfirmSudopassword(l, uid, Attrs): - global SudoPasswd +def FinishConfirmSudopassword(l, uid, Attrs, SudoPasswd): result = "\n" + if len(SudoPasswd) == 0: + return None + res = l.search_s(BaseDn,ldap.SCOPE_ONELEVEL,"uid="+uid, ['sudoPassword']); if len(res) != 1: raise UDFormatError, "Not exactly one hit when searching for user" @@ -511,7 +521,7 @@ def FinishConfirmSudopassword(l, uid, Attrs): newldap = [] for entry in inldap: - Match = re.compile('^('+UUID_FORMAT+') (confirmed:[0-9a-f]{40}|unconfirmed) ([a-z0-9.,*]+) ([^ ]+)$').match(entry) + Match = re.compile('^('+UUID_FORMAT+') (confirmed:[0-9a-f]{40}|unconfirmed) ([a-z0-9.,*-]+) ([^ ]+)$').match(entry) if Match == None: raise UDFormatError, "Could not parse existing sudopasswd entry" uuid = Match.group(1) @@ -550,6 +560,22 @@ def FinishConfirmSudopassword(l, uid, Attrs): return result +def connect_to_ldap_and_check_if_locked(DnRecord): + # Connect to the ldap server + l = connectLDAP() + F = open(PassDir+"/pass-"+pwd.getpwuid(os.getuid())[0],"r"); + AccessPass = F.readline().strip().split(" ") + F.close(); + l.simple_bind_s("uid="+AccessPass[0]+","+BaseDn,AccessPass[1]); + + # Check for a locked account + Attrs = l.search_s(BaseDn,ldap.SCOPE_ONELEVEL,"uid="+GetAttr(DnRecord,"uid")); + if (GetAttr(Attrs[0],"userPassword").find("*LK*") != -1) \ + or GetAttr(Attrs[0],"userPassword").startswith("!"): + raise UDNotAllowedError, "This account is locked"; + + return l + # Handle an [almost] arbitary change def HandleChange(Reply,DnRecord,Key): global PlainText; @@ -557,6 +583,7 @@ def HandleChange(Reply,DnRecord,Key): Result = ""; Attrs = []; + SudoPasswd = {} Show = 0; CommitChanges = 1 for Line in Lines: @@ -574,7 +601,7 @@ def HandleChange(Reply,DnRecord,Key): badkeys = LoadBadSSH() Res = DoPosition(Line,Attrs) or DoDNS(Line,Attrs,DnRecord) or \ DoArbChange(Line,Attrs) or DoSSH(Line,Attrs,badkeys,GetAttr(DnRecord,"uid")) or \ - DoDel(Line,Attrs) or DoRBL(Line,Attrs) or DoConfirmSudopassword(Line) + DoDel(Line,Attrs) or DoRBL(Line,Attrs) or DoConfirmSudopassword(Line, SudoPasswd) except: Res = None; Result = Result + "==> %s: %s\n" %(sys.exc_type,sys.exc_value); @@ -588,27 +615,18 @@ def HandleChange(Reply,DnRecord,Key): Result = Result + Res + "\n"; # Connect to the ldap server - l = connectLDAP() - F = open(PassDir+"/pass-"+pwd.getpwuid(os.getuid())[0],"r"); - AccessPass = F.readline().strip().split(" ") - F.close(); - - l.simple_bind_s("uid="+AccessPass[0]+","+BaseDn,AccessPass[1]); - oldAttrs = l.search_s(BaseDn,ldap.SCOPE_ONELEVEL,"uid="+GetAttr(DnRecord,"uid")); - if ((GetAttr(oldAttrs[0],"userPassword").find("*LK*") != -1) - or GetAttr(oldAttrs[0],"userPassword").startswith("!")): - raise UDNotAllowedError, "This account is locked"; + l = connect_to_ldap_and_check_if_locked(DnRecord) - if CommitChanges == 1: # only if we are still good to go + if CommitChanges == 1 and len(SudoPasswd) > 0: # only if we are still good to go try: - Res = FinishConfirmSudopassword(l, GetAttr(DnRecord,"uid"), Attrs) - Result = Result + Res + "\n"; + Res = FinishConfirmSudopassword(l, GetAttr(DnRecord,"uid"), Attrs, SudoPasswd) + if not Res is None: + Result = Result + Res + "\n"; except Error, e: CommitChanges = 0 Result = Result + "FinishConfirmSudopassword raised an error (%s) - no changes committed\n"%(e); - # Modify the record - if CommitChanges == 1: + if CommitChanges == 1 and len(Attrs) > 0: Dn = "uid=" + GetAttr(DnRecord,"uid") + "," + BaseDn; l.modify_s(Dn,Attrs); @@ -639,13 +657,23 @@ def HandlePing(Reply,DnRecord,Key): return Reply + TemplateSubst(Subst,open(TemplatesDir+"ping-reply","r").read()); + + +def get_crypttype_preamble(key): + if (key[4] == 1): + type = "Your message was encrypted using PGP 2.x\ncompatibility mode."; + else: + type = "Your message was encrypted using GPG (OpenPGP)\ncompatibility "\ + "mode, without IDEA. This message cannot be decoded using PGP 2.x"; + return type + # Handle a change password email sent to the change password address # (this program called with the chpass argument) def HandleChPass(Reply,DnRecord,Key): # Generate a random password Password = GenPass(); Pass = HashPass(Password); - + # Use GPG to encrypt it Message = GPGEncrypt("Your new password is '" + Password + "'\n",\ "0x"+Key[1],Key[4]); @@ -654,33 +682,15 @@ def HandleChPass(Reply,DnRecord,Key): if Message == None: raise UDFormatError, "Unable to generate the encrypted reply, gpg failed."; - if (Key[4] == 1): - Type = "Your message was encrypted using PGP 2.x\ncompatibility mode."; - else: - Type = "Your message was encrypted using GPG (OpenPGP)\ncompatibility "\ - "mode, without IDEA. This message cannot be decoded using PGP 2.x"; - Subst = {}; Subst["__FROM__"] = ChPassFrom; Subst["__EMAIL__"] = EmailAddress(DnRecord); - Subst["__CRYPTTYPE__"] = Type; + Subst["__CRYPTTYPE__"] = get_crypttype_preamble(Key) Subst["__PASSWORD__"] = Message; Subst["__ADMIN__"] = ReplyTo; Reply = Reply + TemplateSubst(Subst,open(TemplatesDir+"passwd-changed","r").read()); - - # Connect to the ldap server - l = connectLDAP() - F = open(PassDir+"/pass-"+pwd.getpwuid(os.getuid())[0],"r"); - AccessPass = F.readline().strip().split(" ") - F.close(); - l.simple_bind_s("uid="+AccessPass[0]+","+BaseDn,AccessPass[1]); - - # Check for a locked account - Attrs = l.search_s(BaseDn,ldap.SCOPE_ONELEVEL,"uid="+GetAttr(DnRecord,"uid")); - if (GetAttr(Attrs[0],"userPassword").find("*LK*") != -1) \ - or GetAttr(Attrs[0],"userPassword").startswith("!"): - raise UDNotAllowedError, "This account is locked"; + l = connect_to_ldap_and_check_if_locked(DnRecord) # Modify the password Rec = [(ldap.MOD_REPLACE,"userPassword","{crypt}"+Pass), (ldap.MOD_REPLACE,"shadowLastChange",str(int(time.time()/24/60/60)))]; @@ -688,7 +698,45 @@ def HandleChPass(Reply,DnRecord,Key): l.modify_s(Dn,Rec); return Reply; - + +def HandleChKrbPass(Reply,DnRecord,Key): + # Connect to the ldap server, will throw an exception if account locked. + l = connect_to_ldap_and_check_if_locked(DnRecord) + + user = GetAttr(DnRecord,"uid") + krb_proc = subprocess.Popen( ('ud-krb-reset', user), stdin=subprocess.PIPE, stdout=subprocess.PIPE, stderr=subprocess.STDOUT) + krb_proc.stdin.close() + out = krb_proc.stdout.readlines() + krb_proc.wait() + exitcode = krb_proc.returncode + + # Use GPG to encrypt it + m = "Tried to reset your kerberos principal's password.\n" + if exitcode == 0: + m += "The exitcode of the reset script was zero, indicating that everything\n" + m += "worked. However, this being software who knows. Script's output below." + else: + m += "The exitcode of the reset script was %d, indicating that something\n"%(exitcode) + m += "went terribly, terribly wrong. Please consult the script's output below\n" + m += "for more information. Contact the admins if you have any questions or\n" + m += "require assitance." + + m += "\n"+''.join( map(lambda x: "| "+x, out) ) + + Message = GPGEncrypt(m, "0x"+Key[1],Key[4]); + if Message == None: + raise UDFormatError, "Unable to generate the encrypted reply, gpg failed."; + + Subst = {}; + Subst["__FROM__"] = ChPassFrom; + Subst["__EMAIL__"] = EmailAddress(DnRecord); + Subst["__CRYPTTYPE__"] = get_crypttype_preamble(Key) + Subst["__PASSWORD__"] = Message; + Subst["__ADMIN__"] = ReplyTo; + Reply = Reply + TemplateSubst(Subst,open(TemplatesDir+"passwd-changed","r").read()); + + return Reply; + # Start of main program # Drop messages from a mailer daemon. @@ -705,8 +753,8 @@ try: # Get the email ErrType = EX_PERMFAIL; ErrMsg = "Failed to understand the email or find a signature:"; - Email = mimetools.Message(sys.stdin,0); - Msg = GetClearSig(Email); + mail = email.parser.Parser().parse(sys.stdin); + Msg = GetClearSig(mail); ErrMsg = "Message is not PGP signed:" if Msg[0].find("-----BEGIN PGP SIGNED MESSAGE-----") == -1 and \ @@ -715,25 +763,22 @@ try: # Check the signature ErrMsg = "Unable to check the signature or the signature was invalid:"; - Res = GPGCheckSig(Msg[0]); + pgp = GPGCheckSig2(Msg[0]) - if Res[0] != None: - raise UDFormatError, Res[0]; + if not pgp.ok: + raise UDFormatError, pgp.why - if Res[3] == None: - raise UDFormatError, "Null signature text"; + if pgp.text is None: + raise UDFormatError, "Null signature text" # Extract the plain message text in the event of mime encoding global PlainText; ErrMsg = "Problem stripping MIME headers from the decoded message" if Msg[1] == 1: - try: - Index = Res[3].index("\n\n") + 2; - except ValueError: - Index = Res[3].index("\n\r\n") + 3; - PlainText = Res[3][Index:]; + e = email.parser.Parser().parsestr(pgp.text) + PlainText = e.get_payload(decode=True) else: - PlainText = Res[3]; + PlainText = pgp.text # Connect to the ldap server ErrType = EX_TEMPFAIL; @@ -743,7 +788,7 @@ try: l.simple_bind_s("",""); # Search for the matching key fingerprint - Attrs = l.search_s(BaseDn,ldap.SCOPE_ONELEVEL,"keyFingerPrint=" + Res[2][1]); + Attrs = l.search_s(BaseDn,ldap.SCOPE_ONELEVEL,"keyFingerPrint=" + pgp.key_fpr) ErrType = EX_PERMFAIL; if len(Attrs) == 0: @@ -754,22 +799,13 @@ try: # Check the signature against the replay cache RC = ReplayCache(ReplayCacheFile); - RC.Clean(); - ErrMsg = "The replay cache rejected your message. Check your clock!"; - Rply = RC.Check(Res[1]); - if Rply != None: - RC.close() - raise UDNotAllowedError, Rply; - RC.Add(Res[1]); - RC.close() + RC.process(pgp.sig_info) # Determine the sender address ErrMsg = "A problem occured while trying to formulate the reply"; - Sender = Email.getheader("Reply-To"); - if Sender == None: - Sender = Email.getheader("From"); - if Sender == None: - raise UDFormatError, "Unable to determine the sender's address"; + Sender = mail['Reply-To'] + if not Sender: Sender = mail['From'] + if not Sender: raise UDFormatError, "Unable to determine the sender's address"; # Formulate a reply Date = time.strftime("%a, %d %b %Y %H:%M:%S +0000",time.gmtime(time.time())); @@ -784,13 +820,16 @@ try: # Dispatch if sys.argv[1] == "ping": - Reply = HandlePing(Reply,Attrs[0],Res[2]); + Reply = HandlePing(Reply,Attrs[0],pgp.key_info); elif sys.argv[1] == "chpass": - if PlainText.strip().find("Please change my Debian password") != 0: - raise UDFormatError,"Please send a signed message where the first line of text is the string 'Please change my Debian password'"; - Reply = HandleChPass(Reply,Attrs[0],Res[2]); + if PlainText.strip().find("Please change my Debian password") >= 0: + Reply = HandleChPass(Reply,Attrs[0],pgp.key_info); + elif PlainText.strip().find("Please change my Kerberos password") >= 0: + Reply = HandleChKrbPass(Reply,Attrs[0],pgp.key_info); + else: + raise UDFormatError,"Please send a signed message where the first line of text is the string 'Please change my Debian password' or some other string we accept here."; elif sys.argv[1] == "change": - Reply = HandleChange(Reply,Attrs[0],Res[2]); + Reply = HandleChange(Reply,Attrs[0],pgp.key_info); else: print sys.argv; raise UDFormatError, "Incorrect Invokation";