Add fallback to apiclient

When apiclient fails using deploycfg, add
a multicast scan looking for replacements.

confluent_osdeploy/common/opt/confluent/bin/apiclient

@@ -5,22 +5,118 @@ except ImportError:
     import httplib as client
 import ctypes
 import ctypes.util
+import glob
 import os
+import select
 import socket
 import subprocess
 import ssl
 import sys
+import struct
 import time
 
 class InvalidApiKey(Exception):
     pass
 
-c_libcrypt = ctypes.CDLL(ctypes.util.find_library('crypt'))
+cryptname = ctypes.util.find_library('crypt')
+if not cryptname:
+    if os.path.exists('/usr/lib64/libcrypt.so.1'):
+        cryptname = 'libcrypt.so.1'
+    elif os.path.exists('/usr/lib64/libcrypt.so.2'):
+        cryptname = 'libcrypt.so.2'
+c_libcrypt = ctypes.CDLL(cryptname)
 c_crypt = c_libcrypt.crypt
 c_crypt.argtypes = (ctypes.c_char_p, ctypes.c_char_p)
 c_crypt.restype = ctypes.c_char_p
 
 
+def get_my_addresses():
+    nlhdrsz = struct.calcsize('IHHII')
+    ifaddrsz = struct.calcsize('BBBBI')
+    # RTM_GETADDR = 22
+    # nlmsghdr struct: u32 len, u16 type, u16 flags, u32 seq, u32 pid
+    nlhdr = struct.pack('IHHII', nlhdrsz + ifaddrsz, 22, 0x301, 0, 0)
+    # ifaddrmsg struct: u8 family, u8 prefixlen, u8 flags, u8 scope, u32 index
+    ifaddrmsg = struct.pack('BBBBI', 0, 0, 0, 0, 0)
+    s = socket.socket(socket.AF_NETLINK, socket.SOCK_RAW, socket.NETLINK_ROUTE)
+    s.bind((0, 0))
+    s.sendall(nlhdr + ifaddrmsg)
+    addrs = []
+    while True:
+        pdata = s.recv(65536)
+        v = memoryview(pdata)
+        if struct.unpack('H', v[4:6])[0] == 3:  # netlink done message
+            break
+        while len(v):
+            length, typ = struct.unpack('IH', v[:6])
+            if typ == 20:
+                fam, plen, _, scope, ridx = struct.unpack('BBBBI', v[nlhdrsz:nlhdrsz+ifaddrsz])
+                if scope in (253, 0):
+                    rta = v[nlhdrsz+ifaddrsz:length]
+                    while len(rta):
+                        rtalen, rtatyp = struct.unpack('HH', rta[:4])
+                        if rtatyp == 1:
+                            addrs.append((fam, rta[4:rtalen], plen, ridx))
+                        if not rtalen:
+                            break
+                        rta = rta[rtalen:]
+            v = v[length:]
+    return addrs
+
+
+def scan_confluents():
+    srvs = {}
+    s6 = socket.socket(socket.AF_INET6, socket.SOCK_DGRAM)
+    s6.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_V6ONLY, 1)
+    s4 = socket.socket(socket.AF_INET, socket.SOCK_DGRAM)
+    s4.setsockopt(socket.SOL_SOCKET, socket.SO_BROADCAST, 1)
+    doneidxs = set([])
+    msg = 'M-SEARCH * HTTP/1.1\r\nST: urn:xcat.org:service:confluent:'
+    with open('/etc/confluent/confluent.deploycfg') as dcfg:
+        for line in dcfg.read().split('\n'):
+            if line.startswith('confluent_uuid:'):
+                confluentuuid = line.split(': ')[1]
+                msg += '/confluentuuid=' + confluentuuid
+                break
+    with open('/sys/devices/virtual/dmi/id/product_uuid') as uuidin:
+        msg += '/uuid=' + uuidin.read().strip()
+    for addrf in glob.glob('/sys/class/net/*/address'):
+        with open(addrf) as addrin:
+            hwaddr = addrin.read().strip()
+            msg += '/mac=' + hwaddr
+    msg = msg.encode('utf8')
+    for addr in get_my_addresses():
+        if addr[0] == socket.AF_INET6:
+            if addr[-1] in doneidxs:
+                continue
+            s6.setsockopt(socket.IPPROTO_IPV6, socket.IPV6_MULTICAST_IF, addr[-1])
+            s6.sendto(msg, ('ff02::c', 1900))
+            doneidxs.add(addr[-1])
+        elif addr[0] == socket.AF_INET:
+            s4.setsockopt(socket.IPPROTO_IP, socket.IP_MULTICAST_IF, addr[1])
+            s4.sendto(msg, ('239.255.255.250', 1900))
+    r = select.select((s4, s6), (), (), 4)
+    if r:
+        r = r[0]
+    while r:
+        for s in r:
+            (rsp, peer) = s.recvfrom(9000)
+            rsp = rsp.split(b'\r\n')
+            current = None
+            for line in rsp:
+                if line.startswith(b'NODENAME: '):
+                    current = {}
+                elif line.startswith(b'DEFAULTNET: 1'):
+                    current['isdefault'] = True
+                elif line.startswith(b'MGTIFACE: '):
+                    current['mgtiface'] = line.replace(b'MGTIFACE: ', b'').strip().decode('utf8')
+            srvs[peer[0]] = current
+        r = select.select((s4, s6), (), (), 2)
+        if r:
+            r = r[0]
+    return srvs
+
+
 def get_net_apikey(nodename, mgr):
     alpha = 'ABCDEFGHIJKLMNOPQRSTUVWXYZabcdefghijklmnopqrstuvwxyz0123456789./'
     newpass = ''.join([alpha[x >> 2] for x in bytearray(os.urandom(32))])
@@ -155,7 +251,7 @@ class HTTPSClient(client.HTTPConnection, object):
             hosts.append(self.v4srv)
         if self.v6srv:
             hosts.append(self.v6srv)
-        for timeo in (0.1, 10):
+        for timeo in (0.1, 5):
             for host in hosts:
                 try:
                     addrinf = socket.getaddrinfo(host, self.port)[0]
@@ -171,7 +267,26 @@ class HTTPSClient(client.HTTPConnection, object):
                 continue
             break
         if not foundsrv:
-            raise Exception('Unable to reach any hosts')
+            srvs = scan_confluents()
+            hosts = []
+            for srv in srvs:
+                if srvs[srv].get('isdefault', False):
+                    hosts = [srv] + hosts
+                else:
+                    hosts = hosts + [srv]
+            for host in hosts:
+                try:
+                    addrinf = socket.getaddrinfo(host, self.port)[0]
+                    psock = socket.socket(addrinf[0])
+                    psock.settimeout(timeo)
+                    psock.connect(addrinf[4])
+                    foundsrv = host
+                    psock.close()
+                    break
+                except OSError:
+                    continue
+            else:
+                raise Exception('Unable to reach any hosts')
         return foundsrv
 
     def connect(self):