make-secnet-sites

   1 #! /usr/bin/env python
   2 #
   3 # This file is part of secnet.
   4 # See README for full list of copyright holders.
   5 #
   6 # secnet is free software; you can redistribute it and/or modify it
   7 # under the terms of the GNU General Public License as published by
   8 # the Free Software Foundation; either version 3 of the License, or
   9 # (at your option) any later version.
  10 #
  11 # secnet is distributed in the hope that it will be useful, but
  12 # WITHOUT ANY WARRANTY; without even the implied warranty of
  13 # MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the GNU
  14 # General Public License for more details.
  15 #
  16 # You should have received a copy of the GNU General Public License
  17 # version 3 along with secnet; if not, see
  18 # https://www.gnu.org/licenses/gpl.html.
  19
  20 """VPN sites file manipulation.
  21
  22 This program enables VPN site descriptions to be submitted for
  23 inclusion in a central database, and allows the resulting database to
  24 be turned into a secnet configuration file.
  25
  26 A database file can be turned into a secnet configuration file simply:
  27 make-secnet-sites.py [infile [outfile]]
  28
  29 It would be wise to run secnet with the "--just-check-config" option
  30 before installing the output on a live system.
  31
  32 The program expects to be invoked via userv to manage the database; it
  33 relies on the USERV_USER and USERV_GROUP environment variables. The
  34 command line arguments for this invocation are:
  35
  36 make-secnet-sites.py -u header-filename groupfiles-directory output-file \
  37   group
  38
  39 All but the last argument are expected to be set by userv; the 'group'
  40 argument is provided by the user. A suitable userv configuration file
  41 fragment is:
  42
  43 reset
  44 no-disconnect-hup
  45 no-suppress-args
  46 cd ~/secnet/sites-test/
  47 execute ~/secnet/make-secnet-sites.py -u vpnheader groupfiles sites
  48
  49 This program is part of secnet. It relies on the "ipaddr" library from
  50 Cendio Systems AB.
  51
  52 """
  53
  54 from __future__ import print_function
  55
  56 import string
  57 import time
  58 import sys
  59 import os
  60 import getopt
  61 import re
  62
  63 import ipaddr
  64
  65 # entry 0 is "near the executable", or maybe from PYTHONPATH=.,
  66 # which we don't want to preempt
  67 sys.path.insert(1,"/usr/local/share/secnet")
  68 sys.path.insert(1,"/usr/share/secnet")
  69 import ipaddrset
  70
  71 VERSION="0.1.18"
  72
  73 # Are we being invoked from userv?
  74 service=0
  75 # If we are, which group does the caller want to modify?
  76 group=None
  77
  78 if len(sys.argv)<2:
  79         inputfile=None
  80         of=sys.stdout
  81 else:
  82         if sys.argv[1]=='-u':
  83                 if len(sys.argv)!=6:
  84                         print("Wrong number of arguments")
  85                         sys.exit(1)
  86                 service=1
  87                 header=sys.argv[2]
  88                 groupfiledir=sys.argv[3]
  89                 sitesfile=sys.argv[4]
  90                 group=sys.argv[5]
  91                 if not os.environ.has_key("USERV_USER"):
  92                         print("Environment variable USERV_USER not found")
  93                         sys.exit(1)
  94                 user=os.environ["USERV_USER"]
  95                 # Check that group is in USERV_GROUP
  96                 if not os.environ.has_key("USERV_GROUP"):
  97                         print("Environment variable USERV_GROUP not found")
  98                         sys.exit(1)
  99                 ugs=os.environ["USERV_GROUP"]
 100                 ok=0
 101                 for i in string.split(ugs):
 102                         if group==i: ok=1
 103                 if not ok:
 104                         print("caller not in group %s"%group)
 105                         sys.exit(1)
 106         else:
 107                 if sys.argv[1]=='-P':
 108                         prefix=sys.argv[2]
 109                         sys.argv[1:3]=[]
 110                 if len(sys.argv)>3:
 111                         print("Too many arguments")
 112                         sys.exit(1)
 113                 inputfile=sys.argv[1]
 114                 of=sys.stdout
 115                 if len(sys.argv)>2:
 116                         of=open(sys.argv[2],'w')
 117
 118 # Classes describing possible datatypes in the configuration file
 119
 120 class basetype:
 121         "Common protocol for configuration types."
 122         def add(self,obj,w):
 123                 complain("%s %s already has property %s defined"%
 124                         (obj.type,obj.name,w[0]))
 125
 126 class conflist:
 127         "A list of some kind of configuration type."
 128         def __init__(self,subtype,w):
 129                 self.subtype=subtype
 130                 self.list=[subtype(w)]
 131         def add(self,obj,w):
 132                 self.list.append(self.subtype(w))
 133         def __str__(self):
 134                 return ', '.join(map(str, self.list))
 135 def listof(subtype):
 136         return lambda w: conflist(subtype, w)
 137
 138 class single_ipaddr (basetype):
 139         "An IP address"
 140         def __init__(self,w):
 141                 self.addr=ipaddr.IPAddress(w[1])
 142         def __str__(self):
 143                 return '"%s"'%self.addr
 144
 145 class networks (basetype):
 146         "A set of IP addresses specified as a list of networks"
 147         def __init__(self,w):
 148                 self.set=ipaddrset.IPAddressSet()
 149                 for i in w[1:]:
 150                         x=ipaddr.IPNetwork(i,strict=True)
 151                         self.set.append([x])
 152         def __str__(self):
 153                 return ",".join(map((lambda n: '"%s"'%n), self.set.networks()))
 154
 155 class dhgroup (basetype):
 156         "A Diffie-Hellman group"
 157         def __init__(self,w):
 158                 self.mod=w[1]
 159                 self.gen=w[2]
 160         def __str__(self):
 161                 return 'diffie-hellman("%s","%s")'%(self.mod,self.gen)
 162
 163 class hash (basetype):
 164         "A choice of hash function"
 165         def __init__(self,w):
 166                 self.ht=w[1]
 167                 if (self.ht!='md5' and self.ht!='sha1'):
 168                         complain("unknown hash type %s"%(self.ht))
 169         def __str__(self):
 170                 return '%s'%(self.ht)
 171
 172 class email (basetype):
 173         "An email address"
 174         def __init__(self,w):
 175                 self.addr=w[1]
 176         def __str__(self):
 177                 return '<%s>'%(self.addr)
 178
 179 class boolean (basetype):
 180         "A boolean"
 181         def __init__(self,w):
 182                 if re.match('[TtYy1]',w[1]):
 183                         self.b=True
 184                 elif re.match('[FfNn0]',w[1]):
 185                         self.b=False
 186                 else:
 187                         complain("invalid boolean value");
 188         def __str__(self):
 189                 return ['False','True'][self.b]
 190
 191 class num (basetype):
 192         "A decimal number"
 193         def __init__(self,w):
 194                 self.n=string.atol(w[1])
 195         def __str__(self):
 196                 return '%d'%(self.n)
 197
 198 class address (basetype):
 199         "A DNS name and UDP port number"
 200         def __init__(self,w):
 201                 self.adr=w[1]
 202                 self.port=string.atoi(w[2])
 203                 if (self.port<1 or self.port>65535):
 204                         complain("invalid port number")
 205         def __str__(self):
 206                 return '"%s"; port %d'%(self.adr,self.port)
 207
 208 class rsakey (basetype):
 209         "An RSA public key"
 210         def __init__(self,w):
 211                 self.l=string.atoi(w[1])
 212                 self.e=w[2]
 213                 self.n=w[3]
 214         def __str__(self):
 215                 return 'rsa-public("%s","%s")'%(self.e,self.n)
 216
 217 # Possible properties of configuration nodes
 218 keywords={
 219  'contact':(email,"Contact address"),
 220  'dh':(dhgroup,"Diffie-Hellman group"),
 221  'hash':(hash,"Hash function"),
 222  'key-lifetime':(num,"Maximum key lifetime (ms)"),
 223  'setup-timeout':(num,"Key setup timeout (ms)"),
 224  'setup-retries':(num,"Maximum key setup packet retries"),
 225  'wait-time':(num,"Time to wait after unsuccessful key setup (ms)"),
 226  'renegotiate-time':(num,"Time after key setup to begin renegotiation (ms)"),
 227  'restrict-nets':(networks,"Allowable networks"),
 228  'networks':(networks,"Claimed networks"),
 229  'pubkey':(rsakey,"RSA public site key"),
 230  'peer':(single_ipaddr,"Tunnel peer IP address"),
 231  'address':(address,"External contact address and port"),
 232  'mobile':(boolean,"Site is mobile"),
 233 }
 234
 235 def sp(name,value):
 236         "Simply output a property - the default case"
 237         return "%s %s;\n"%(name,value)
 238
 239 # All levels support these properties
 240 global_properties={
 241         'contact':(lambda name,value:"# Contact email address: %s\n"%(value)),
 242         'dh':sp,
 243         'hash':sp,
 244         'key-lifetime':sp,
 245         'setup-timeout':sp,
 246         'setup-retries':sp,
 247         'wait-time':sp,
 248         'renegotiate-time':sp,
 249         'restrict-nets':(lambda name,value:"# restrict-nets %s\n"%value),
 250 }
 251
 252 class level:
 253         "A level in the configuration hierarchy"
 254         depth=0
 255         leaf=0
 256         allow_properties={}
 257         require_properties={}
 258         def __init__(self,w):
 259                 self.name=w[1]
 260                 self.properties={}
 261                 self.children={}
 262         def indent(self,w,t):
 263                 w.write("                 "[:t])
 264         def prop_out(self,n):
 265                 return self.allow_properties[n](n,str(self.properties[n]))
 266         def output_props(self,w,ind):
 267                 for i in self.properties.keys():
 268                         if self.allow_properties[i]:
 269                                 self.indent(w,ind)
 270                                 w.write("%s"%self.prop_out(i))
 271         def output_data(self,w,ind,np):
 272                 self.indent(w,ind)
 273                 w.write("%s {\n"%(self.name))
 274                 self.output_props(w,ind+2)
 275                 if self.depth==1: w.write("\n");
 276                 for c in self.children.values():
 277                         c.output_data(w,ind+2,np+self.name+"/")
 278                 self.indent(w,ind)
 279                 w.write("};\n")
 280
 281 class vpnlevel(level):
 282         "VPN level in the configuration hierarchy"
 283         depth=1
 284         leaf=0
 285         type="vpn"
 286         allow_properties=global_properties.copy()
 287         require_properties={
 288          'contact':"VPN admin contact address"
 289         }
 290         def __init__(self,w):
 291                 level.__init__(self,w)
 292         def output_vpnflat(self,w,ind,h):
 293                 "Output flattened list of site names for this VPN"
 294                 self.indent(w,ind)
 295                 w.write("%s {\n"%(self.name))
 296                 for i in self.children.keys():
 297                         self.children[i].output_vpnflat(w,ind+2,
 298                                 h+"/"+self.name+"/"+i)
 299                 w.write("\n")
 300                 self.indent(w,ind+2)
 301                 w.write("all-sites %s;\n"%
 302                         string.join(self.children.keys(),','))
 303                 self.indent(w,ind)
 304                 w.write("};\n")
 305
 306 class locationlevel(level):
 307         "Location level in the configuration hierarchy"
 308         depth=2
 309         leaf=0
 310         type="location"
 311         allow_properties=global_properties.copy()
 312         require_properties={
 313          'contact':"Location admin contact address",
 314         }
 315         def __init__(self,w):
 316                 level.__init__(self,w)
 317                 self.group=w[2]
 318         def output_vpnflat(self,w,ind,h):
 319                 self.indent(w,ind)
 320                 # The "h=h,self=self" abomination below exists because
 321                 # Python didn't support nested_scopes until version 2.1
 322                 w.write("%s %s;\n"%(self.name,string.join(
 323                         map(lambda x,h=h,self=self:
 324                                 h+"/"+x,self.children.keys()),',')))
 325
 326 class sitelevel(level):
 327         "Site level (i.e. a leafnode) in the configuration hierarchy"
 328         depth=3
 329         leaf=1
 330         type="site"
 331         allow_properties=global_properties.copy()
 332         allow_properties.update({
 333          'address':sp,
 334          'networks':None,
 335          'peer':None,
 336          'pubkey':(lambda n,v:"key %s;\n"%v),
 337          'mobile':sp,
 338         })
 339         require_properties={
 340          'dh':"Diffie-Hellman group",
 341          'contact':"Site admin contact address",
 342          'networks':"Networks claimed by the site",
 343          'hash':"hash function",
 344          'peer':"Gateway address of the site",
 345          'pubkey':"RSA public key of the site",
 346         }
 347         def __init__(self,w):
 348                 level.__init__(self,w)
 349         def output_data(self,w,ind,np):
 350                 self.indent(w,ind)
 351                 w.write("%s {\n"%(self.name))
 352                 self.indent(w,ind+2)
 353                 w.write("name \"%s\";\n"%(np+self.name))
 354                 self.output_props(w,ind+2)
 355                 self.indent(w,ind+2)
 356                 w.write("link netlink {\n");
 357                 self.indent(w,ind+4)
 358                 w.write("routes %s;\n"%str(self.properties["networks"]))
 359                 self.indent(w,ind+4)
 360                 w.write("ptp-address %s;\n"%str(self.properties["peer"]))
 361                 self.indent(w,ind+2)
 362                 w.write("};\n")
 363                 self.indent(w,ind)
 364                 w.write("};\n")
 365
 366 # Levels in the configuration file
 367 # (depth,properties)
 368 levels={'vpn':vpnlevel, 'location':locationlevel, 'site':sitelevel}
 369
 370 # Reserved vpn/location/site names
 371 reserved={'all-sites':None}
 372 reserved.update(keywords)
 373 reserved.update(levels)
 374
 375 def complain(msg):
 376         "Complain about a particular input line"
 377         global complaints
 378         print(("%s line %d: "%(file,line))+msg)
 379         complaints=complaints+1
 380 def moan(msg):
 381         "Complain about something in general"
 382         global complaints
 383         print(msg);
 384         complaints=complaints+1
 385
 386 root=level(['root','root'])   # All vpns are children of this node
 387 obstack=[root]
 388 allow_defs=0   # Level above which new definitions are permitted
 389 prefix=''
 390
 391 def set_property(obj,w):
 392         "Set a property on a configuration node"
 393         if obj.properties.has_key(w[0]):
 394                 obj.properties[w[0]].add(obj,w)
 395         else:
 396                 obj.properties[w[0]]=keywords[w[0]][0](w)
 397
 398 def pline(i,allow_include=False):
 399         "Process a configuration file line"
 400         global allow_defs, obstack, root
 401         w=string.split(i.rstrip('\n'))
 402         if len(w)==0: return [i]
 403         keyword=w[0]
 404         current=obstack[len(obstack)-1]
 405         if keyword=='end-definitions':
 406                 allow_defs=sitelevel.depth
 407                 obstack=[root]
 408                 return [i]
 409         if keyword=='include':
 410                 if not allow_include:
 411                         complain("include not permitted here")
 412                         return []
 413                 if len(w) != 2:
 414                         complain("include requires one argument")
 415                         return []
 416                 newfile=os.path.join(os.path.dirname(file),w[1])
 417                 return pfilepath(newfile,allow_include=allow_include)
 418         if levels.has_key(keyword):
 419                 # We may go up any number of levels, but only down by one
 420                 newdepth=levels[keyword].depth
 421                 currentdepth=len(obstack) # actually +1...
 422                 if newdepth<=currentdepth:
 423                         obstack=obstack[:newdepth]
 424                 if newdepth>currentdepth:
 425                         complain("May not go from level %d to level %d"%
 426                                 (currentdepth-1,newdepth))
 427                 # See if it's a new one (and whether that's permitted)
 428                 # or an existing one
 429                 current=obstack[len(obstack)-1]
 430                 if current.children.has_key(w[1]):
 431                         # Not new
 432                         current=current.children[w[1]]
 433                         if service and group and current.depth==2:
 434                                 if group!=current.group:
 435                                         complain("Incorrect group!")
 436                 else:
 437                         # New
 438                         # Ignore depth check for now
 439                         nl=levels[keyword](w)
 440                         if nl.depth<allow_defs:
 441                                 complain("New definitions not allowed at "
 442                                         "level %d"%nl.depth)
 443                                 # we risk crashing if we continue
 444                                 sys.exit(1)
 445                         current.children[w[1]]=nl
 446                         current=nl
 447                 obstack.append(current)
 448                 return [i]
 449         if not current.allow_properties.has_key(keyword):
 450                 complain("Property %s not allowed at %s level"%
 451                         (keyword,current.type))
 452                 return []
 453         elif current.depth == vpnlevel.depth < allow_defs:
 454                 complain("Not allowed to set VPN properties here")
 455                 return []
 456         else:
 457                 set_property(current,w)
 458                 return [i]
 459
 460         complain("unknown keyword '%s'"%(keyword))
 461
 462 def pfilepath(pathname,allow_include=False):
 463         f=open(pathname)
 464         outlines=pfile(pathname,f.readlines(),allow_include=allow_include)
 465         f.close()
 466         return outlines
 467
 468 def pfile(name,lines,allow_include=False):
 469         "Process a file"
 470         global file,line
 471         file=name
 472         line=0
 473         outlines=[]
 474         for i in lines:
 475                 line=line+1
 476                 if (i[0]=='#'): continue
 477                 outlines += pline(i,allow_include=allow_include)
 478         return outlines
 479
 480 def outputsites(w):
 481         "Output include file for secnet configuration"
 482         w.write("# secnet sites file autogenerated by make-secnet-sites "
 483                 +"version %s\n"%VERSION)
 484         w.write("# %s\n"%time.asctime(time.localtime(time.time())))
 485         w.write("# Command line: %s\n\n"%string.join(sys.argv))
 486
 487         # Raw VPN data section of file
 488         w.write(prefix+"vpn-data {\n")
 489         for i in root.children.values():
 490                 i.output_data(w,2,"")
 491         w.write("};\n")
 492
 493         # Per-VPN flattened lists
 494         w.write(prefix+"vpn {\n")
 495         for i in root.children.values():
 496                 i.output_vpnflat(w,2,prefix+"vpn-data")
 497         w.write("};\n")
 498
 499         # Flattened list of sites
 500         w.write(prefix+"all-sites %s;\n"%string.join(
 501                 map(lambda x:"%svpn/%s/all-sites"%(prefix,x),
 502                         root.children.keys()),","))
 503
 504 line=0
 505 file=None
 506 complaints=0
 507
 508 # Sanity check section
 509 # Delete nodes where leaf=0 that have no children
 510
 511 def live(n):
 512         "Number of leafnodes below node n"
 513         if n.leaf: return 1
 514         for i in n.children.keys():
 515                 if live(n.children[i]): return 1
 516         return 0
 517 def delempty(n):
 518         "Delete nodes that have no leafnode children"
 519         for i in n.children.keys():
 520                 delempty(n.children[i])
 521                 if not live(n.children[i]):
 522                         del n.children[i]
 523
 524 # Check that all constraints are met (as far as I can tell
 525 # restrict-nets/networks/peer are the only special cases)
 526
 527 def checkconstraints(n,p,ra):
 528         new_p=p.copy()
 529         new_p.update(n.properties)
 530         for i in n.require_properties.keys():
 531                 if not new_p.has_key(i):
 532                         moan("%s %s is missing property %s"%
 533                                 (n.type,n.name,i))
 534         for i in new_p.keys():
 535                 if not n.allow_properties.has_key(i):
 536                         moan("%s %s has forbidden property %s"%
 537                                 (n.type,n.name,i))
 538         # Check address range restrictions
 539         if n.properties.has_key("restrict-nets"):
 540                 new_ra=ra.intersection(n.properties["restrict-nets"].set)
 541         else:
 542                 new_ra=ra
 543         if n.properties.has_key("networks"):
 544                 if not n.properties["networks"].set <= new_ra:
 545                         moan("%s %s networks out of bounds"%(n.type,n.name))
 546                 if n.properties.has_key("peer"):
 547                         if not n.properties["networks"].set.contains(
 548                                 n.properties["peer"].addr):
 549                                 moan("%s %s peer not in networks"%(n.type,n.name))
 550         for i in n.children.keys():
 551                 checkconstraints(n.children[i],new_p,new_ra)
 552
 553 if service:
 554         headerinput=pfilepath(header,allow_include=True)
 555         userinput=sys.stdin.readlines()
 556         pfile("user input",userinput)
 557 else:
 558         if inputfile is None:
 559                 pfile("stdin",sys.stdin.readlines())
 560         else:
 561                 pfilepath(inputfile)
 562
 563 delempty(root)
 564 checkconstraints(root,{},ipaddrset.complete_set())
 565
 566 if complaints>0:
 567         if complaints==1: print("There was 1 problem.")
 568         else: print("There were %d problems."%(complaints))
 569         sys.exit(1)
 570
 571 if service:
 572         # Put the user's input into their group file, and rebuild the main
 573         # sites file
 574         f=open(groupfiledir+"/T"+group,'w')
 575         f.write("# Section submitted by user %s, %s\n"%
 576                 (user,time.asctime(time.localtime(time.time()))))
 577         f.write("# Checked by make-secnet-sites version %s\n\n"%VERSION)
 578         for i in userinput: f.write(i)
 579         f.write("\n")
 580         f.close()
 581         os.rename(groupfiledir+"/T"+group,groupfiledir+"/R"+group)
 582         f=open(sitesfile+"-tmp",'w')
 583         f.write("# sites file autogenerated by make-secnet-sites\n")
 584         f.write("# generated %s, invoked by %s\n"%
 585                 (time.asctime(time.localtime(time.time())),user))
 586         f.write("# use make-secnet-sites to turn this file into a\n")
 587         f.write("# valid /etc/secnet/sites.conf file\n\n")
 588         for i in headerinput: f.write(i)
 589         files=os.listdir(groupfiledir)
 590         for i in files:
 591                 if i[0]=='R':
 592                         j=open(groupfiledir+"/"+i)
 593                         f.write(j.read())
 594                         j.close()
 595         f.write("# end of sites file\n")
 596         f.close()
 597         os.rename(sitesfile+"-tmp",sitesfile)
 598 else:
 599         outputsites(of)