#!/usr/bin/python
#
#	backend code for upgrading from Samba3
#	Copyright Jelmer Vernooij 2005-2007
#	Released under the GNU GPL v3 or later
#

"""Support code for upgrading from Samba 3 to Samba 4."""

from provision import findnss
import provision
import grp
import pwd
import uuid

def regkey_to_dn(name):
    """Convert a registry key to a DN.
    
    :name: The registry key name.
    :return: A matching DN."""
    dn = "hive=NONE"

    if name == "":
        return dn

    for el in name.split("/"):
        dn = "key=%s," % el + dn

    return dn

# Where prefix is any of:
# - HKLM
#   HKU
#   HKCR
#   HKPD
#   HKPT
#

def upgrade_registry(regdb,prefix,ldb):
    """Migrate registry contents."""
    assert regdb is not None
    prefix_up = prefix.upper()
    ldif = []

    for rk in regdb.keys:
        pts = rk.name.split("/")

        # Only handle selected hive
        if pts[0].upper() != prefix_up:
            continue

        keydn = regkey_to_dn(rk.name)

        pts = rk.name.split("/")

        # Convert key name to dn
        ldif[rk.name] = """
dn: %s
name: %s

""" % (keydn, pts[0])
        
        for rv in rk.values:
            ldif[rk.name + " (" + rv.name + ")"] = """
dn: %s,value=%s
value: %s
type: %d
data:: %s""" % (keydn, rv.name, rv.name, rv.type, ldb.encode(rv.data))

    return ldif

def upgrade_sam_policy(samba3,dn):
    ldif = """
dn: %s
changetype: modify
replace: minPwdLength
minPwdLength: %d
pwdHistoryLength: %d
minPwdAge: %d
maxPwdAge: %d
lockoutDuration: %d
samba3ResetCountMinutes: %d
samba3UserMustLogonToChangePassword: %d
samba3BadLockoutMinutes: %d
samba3DisconnectTime: %d

""" % (dn, samba3.policy.min_password_length, 
    samba3.policy.password_history, samba3.policy.minimum_password_age,
    samba3.policy.maximum_password_age, samba3.policy.lockout_duration,
    samba3.policy.reset_count_minutes, samba3.policy.user_must_logon_to_change_password,
    samba3.policy.bad_lockout_minutes, samba3.policy.disconnect_time)
    
    return ldif

def upgrade_sam_account(ldb,acc,domaindn,domainsid):
    """Upgrade a SAM account."""
    if acc.nt_username is None or acc.nt_username == "":
        acc.nt_username = acc.username

    if acc.fullname is None:
        acc.fullname = pwd.getpwnam(acc.fullname)[4]

    acc.fullname = acc.fullname.split(",")[0]

    if acc.fullname is None:
        acc.fullname = acc.username
    
    assert acc.fullname is not None
    assert acc.nt_username is not None

    ldif = """dn: cn=%s,%s
objectClass: top
objectClass: user
lastLogon: %d
lastLogoff: %d
unixName: %s
sAMAccountName: %s
cn: %s
description: %s
primaryGroupID: %d
badPwdcount: %d
logonCount: %d
samba3Domain: %s
samba3DirDrive: %s
samba3MungedDial: %s
samba3Homedir: %s
samba3LogonScript: %s
samba3ProfilePath: %s
samba3Workstations: %s
samba3KickOffTime: %d
samba3BadPwdTime: %d
samba3PassLastSetTime: %d
samba3PassCanChangeTime: %d
samba3PassMustChangeTime: %d
objectSid: %s-%d
lmPwdHash:: %s
ntPwdHash:: %s

""" % (ldb.dn_escape(acc.fullname), domaindn, acc.logon_time, acc.logoff_time, acc.username, acc.nt_username, acc.nt_username, 
acc.acct_desc, acc.group_rid, acc.bad_password_count, acc.logon_count,
acc.domain, acc.dir_drive, acc.munged_dial, acc.homedir, acc.logon_script, 
acc.profile_path, acc.workstations, acc.kickoff_time, acc.bad_password_time, 
acc.pass_last_set_time, acc.pass_can_change_time, acc.pass_must_change_time, domainsid, acc.user_rid,
    ldb.encode(acc.lm_pw), ldb.encode(acc.nt_pw))

    return ldif

def upgrade_sam_group(group,domaindn):
    """Upgrade a SAM group."""
    if group.sid_name_use == 5: # Well-known group
        return None

    if group.nt_name in ("Domain Guests", "Domain Users", "Domain Admins"):
        return None
    
    if group.gid == -1:
        gr = grp.getgrnam(grp.nt_name)
    else:
        gr = grp.getgrgid(grp.gid)

    if gr is None:
        group.unixname = "UNKNOWN"
    else:
        group.unixname = gr.gr_name

    assert group.unixname is not None
    
    ldif = """dn: cn=%s,%s
objectClass: top
objectClass: group
description: %s
cn: %s
objectSid: %s
unixName: %s
samba3SidNameUse: %d
""" % (group.nt_name, domaindn, 
group.comment, group.nt_name, group.sid, group.unixname, group.sid_name_use)

    return ldif

def upgrade_winbind(samba3,domaindn):
    ldif = """
        
dn: dc=none
userHwm: %d
groupHwm: %d

""" % (samba3.idmap.user_hwm, samba3.idmap.group_hwm)

    for m in samba3.idmap.mappings:
        ldif += """
dn: SID=%s,%s
SID: %s
type: %d
unixID: %d""" % (m.sid, domaindn, m.sid, m.type, m.unix_id)
    
    return ldif

def upgrade_wins(samba3):
    """Upgrade the WINS database."""
    ldif = ""
    version_id = 0

    for e in samba3.winsentries:
        now = sys.nttime()
        ttl = sys.unix2nttime(e.ttl)

        version_id+=1

        numIPs = len(e.ips)

        if e.type == 0x1C:
            rType = 0x2
        elif e.type & 0x80:
            if numIPs > 1:
                rType = 0x2
            else:
                rType = 0x1
        else:
            if numIPs > 1:
                rType = 0x3
            else:
                rType = 0x0

        if ttl > now:
            rState = 0x0 # active
        else:
            rState = 0x1 # released

        nType = ((e.nb_flags & 0x60)>>5)

        ldif += """
dn: name=%s,type=0x%02X
type: 0x%02X
name: %s
objectClass: winsRecord
recordType: %u
recordState: %u
nodeType: %u
isStatic: 0
expireTime: %s
versionID: %llu
""" % (e.name, e.type, e.type, e.name, 
   rType, rState, nType, 
   ldaptime(ttl), version_id)

        for ip in e.ips:
            ldif += "address: %s\n" % ip

    ldif += """
dn: CN=VERSION
objectClass: winsMaxVersion
maxVersion: %llu
""" % version_id

    return ldif

def upgrade_provision(lp, samba3):
    domainname = samba3.configuration.get("workgroup")
    
    if domainname is None:
        domainname = samba3.secrets.domains[0].name
        print "No domain specified in smb.conf file, assuming '%s'\n" % domainname
    
    domsec = samba3.find_domainsecrets(domainname)
    hostsec = samba3.find_domainsecrets(hostname())
    realm = samba3.configuration.get("realm")

    if realm is None:
        realm = domainname
        print "No realm specified in smb.conf file, assuming '%s'\n" % realm
    random_init(local)

    subobj.realm        = realm
    subobj.domain       = domainname

    if domsec is not None:
        subobj.DOMAINGUID   = domsec.guid
        subobj.DOMAINSID    = domsec.sid
    else:
        print "Can't find domain secrets for '%s'; using random SID and GUID\n" % domainname
        subobj.DOMAINGUID = uuid.random()
        subobj.DOMAINSID = randsid()
    
    if hostsec:
        hostguid = hostsec.guid
    subobj.krbtgtpass   = randpass(12)
    subobj.machinepass  = randpass(12)
    subobj.adminpass    = randpass(12)
    subobj.datestring   = datestring()
    subobj.root         = findnss(pwd.getpwnam, "root")[4]
    subobj.nobody       = findnss(pwd.getpwnam, "nobody")[4]
    subobj.nogroup      = findnss(grp.getgrnam, "nogroup", "nobody")[2]
    subobj.wheel        = findnss(grp.getgrnam, "wheel", "root")[2]
    subobj.users        = findnss(grp.getgrnam, "users", "guest", "other")[2]
    subobj.dnsdomain    = subobj.realm.lower()
    subobj.dnsname      = "%s.%s" % (subobj.hostname.lower(), subobj.dnsdomain)
    subobj.basedn       = "DC=" + ",DC=".join(subobj.realm.split("."))
    rdn_list = subobj.dnsdomain.split(".")
    subobj.domaindn     = "DC=" + ",DC=".join(rdn_list)
    subobj.domaindn_ldb = "users.ldb"
    subobj.rootdn       = subobj.domaindn

    modules_list        = ["rootdse",
                    "kludge_acl",
                    "paged_results",
                    "server_sort",
                    "extended_dn",
                    "asq",
                    "samldb",
                    "password_hash",
                    "operational",
                    "objectclass",
                    "rdn_name",
                    "show_deleted",
                    "partition"]
    subobj.modules_list = ",".join(modules_list)

    return subobj

smbconf_keep = [
    "dos charset", 
    "unix charset",
    "display charset",
    "comment",
    "path",
    "directory",
    "workgroup",
    "realm",
    "netbios name",
    "netbios aliases",
    "netbios scope",
    "server string",
    "interfaces",
    "bind interfaces only",
    "security",
    "auth methods",
    "encrypt passwords",
    "null passwords",
    "obey pam restrictions",
    "password server",
    "smb passwd file",
    "private dir",
    "passwd chat",
    "password level",
    "lanman auth",
    "ntlm auth",
    "client NTLMv2 auth",
    "client lanman auth",
    "client plaintext auth",
    "read only",
    "hosts allow",
    "hosts deny",
    "log level",
    "debuglevel",
    "log file",
    "smb ports",
    "large readwrite",
    "max protocol",
    "min protocol",
    "unicode",
    "read raw",
    "write raw",
    "disable netbios",
    "nt status support",
    "announce version",
    "announce as",
    "max mux",
    "max xmit",
    "name resolve order",
    "max wins ttl",
    "min wins ttl",
    "time server",
    "unix extensions",
    "use spnego",
    "server signing",
    "client signing",
    "max connections",
    "paranoid server security",
    "socket options",
    "strict sync",
    "max print jobs",
    "printable",
    "print ok",
    "printer name",
    "printer",
    "map system",
    "map hidden",
    "map archive",
    "preferred master",
    "prefered master",
    "local master",
    "browseable",
    "browsable",
    "wins server",
    "wins support",
    "csc policy",
    "strict locking",
    "preload",
    "auto services",
    "lock dir",
    "lock directory",
    "pid directory",
    "socket address",
    "copy",
    "include",
    "available",
    "volume",
    "fstype",
    "panic action",
    "msdfs root",
    "host msdfs",
    "winbind separator"]

def upgrade_smbconf(oldconf,mark):
    """Remove configuration variables not present in Samba4

    :param oldconf: Old configuration structure
    :param mark: Whether removed configuration variables should be 
        kept in the new configuration as "samba3:<name>"
    """
    data = oldconf.data()
    newconf = param_init()

    for s in data:
        for p in data[s]:
            keep = False
            for k in smbconf_keep:
                if smbconf_keep[k] == p:
                    keep = True
                    break

            if keep:
                newconf.set(s, p, oldconf.get(s, p))
            elif mark:
                newconf.set(s, "samba3:"+p, oldconf.get(s,p))

    if oldconf.get("domain logons") == "True":
        newconf.set("server role", "domain controller")
    else:
        if oldconf.get("security") == "user":
            newconf.set("server role", "standalone")
        else:
            newconf.set("server role", "member server")

    return newconf

def upgrade(subobj, samba3, message, paths, session_info, credentials):
    ret = 0
    lp = loadparm_init()
    samdb = Ldb(paths.samdb, session_info=session_info, credentials=credentials)

    message("Writing configuration")
    newconf = upgrade_smbconf(samba3.configuration,True)
    newconf.save(paths.smbconf)

    message("Importing account policies")
    ldif = upgrade_sam_policy(samba3,subobj.BASEDN)
    samdb.modify(ldif)
    regdb = Ldb(paths.hklm)

    regdb.modify("""
dn: value=RefusePasswordChange,key=Parameters,key=Netlogon,key=Services,key=CurrentControlSet,key=System,HIVE=NONE
replace: type
type: 4
replace: data
data: %d
""" % samba3.policy.refuse_machine_password_change)

    message("Importing users")
    for account in samba3.samaccounts:
        msg = "... " + account.username
        ldif = upgrade_sam_account(samdb, accounts,subobj.BASEDN,subobj.DOMAINSID)
        try:
            samdb.add(ldif)
        except LdbError, e:
            # FIXME: Ignore 'Record exists' errors
            msg += "... error: " + str(e)
            ret += 1; 
        message(msg)

    message("Importing groups")
    for mapping in samba3.groupmappings:
        msg = "... " + mapping.nt_name
        ldif = upgrade_sam_group(mapping, subobj.BASEDN)
        if ldif is not None:
            try:
                samdb.add(ldif)
            except LdbError, e:
                # FIXME: Ignore 'Record exists' errors
                msg += "... error: " + str(e)
                ret += 1
        message(msg)

    message("Importing registry data")
    for hive in ["hkcr","hkcu","hklm","hkpd","hku","hkpt"]:
        message("... " + hive)
        regdb = Ldb(paths[hive])
        ldif = upgrade_registry(samba3.registry, hive, regdb)
        for j in ldif:
            msg = "... ... " + j
            try:
                regdb.add(ldif[j])
            except LdbError, e:
                # FIXME: Ignore 'Record exists' errors
                msg += "... error: " + str(e)
                ret += 1
            message(msg)

    message("Importing WINS data")
    winsdb = Ldb(paths.winsdb)
    ldb_erase(winsdb)

    ldif = upgrade_wins(samba3)
    winsdb.add(ldif)

    # figure out ldapurl, if applicable
    ldapurl = None
    pdb = samba3.configuration.get_list("passdb backend")
    if pdb is not None:
        for backend in pdb:
            if len(backend) >= 7 and backend[0:7] == "ldapsam":
                ldapurl = backend[7:]

    # URL was not specified in passdb backend but ldap /is/ used
    if ldapurl == "":
        ldapurl = "ldap://%s" % samba3.configuration.get("ldap server")

    # Enable samba3sam module if original passdb backend was ldap
    if ldapurl is not None:
        message("Enabling Samba3 LDAP mappings for SAM database")

        samdb.modify("""
dn: @MODULES
changetype: modify
replace: @LIST
@LIST: samldb,operational,objectguid,rdn_name,samba3sam
""")

        samdb.add({"dn": "@MAP=samba3sam", "@MAP_URL": ldapurl})

    return ret

def upgrade_verify(subobj, samba3, paths, message):
    message("Verifying account policies")

    samldb = Ldb(paths.samdb)

    for account in samba3.samaccounts:
        msg = samldb.search("(&(sAMAccountName=" + account.nt_username + ")(objectclass=user))")
        assert(len(msg) >= 1)
    
    # FIXME