1 Patch to address a scalability issue when using dnsmasq in Openstack,

     2 that causes DHCP to be extremely slow.

     3 

     4 This patch was developed in-house. Since it is Solaris-specific, it is not

     5 suitable for upstream.

     6 

     7 --- dnsmasq-2.75/src/dhcp-common.c	2015-07-30 12:59:07.000000000 -0700

     8 +++ new/src/dhcp-common.c	2016-09-22 15:12:02.104708123 -0700

     9 @@ -493,6 +493,58 @@

    10        errno != EPERM)

    11      die(_("failed to set SO_BINDTODEVICE on DHCP socket: %s"), NULL, EC_BADNET);

    12  }

    13 +#elif defined(HAVE_SOLARIS_NETWORK)

    14 +int which_ifindex(void)

    15 +{

    16 +  /* If we are doing DHCP on exactly one interface, and using Solaris, we want

    17 +   * to limit packet transmission/reception to that interface using IP_BOUND_IF

    18 +   * for IPv4 and IPV6_BOUND_IF for IPv6. This is for the use case of OpenStack,

    19 +   * which runs a new dnsmasq instance for each network it creates. Without this

    20 +   * socket option, each of the dnsmasq process would unnecessarily process 

    21 +   * packets that arrive on other interfaces as well, thus slowing down the 

    22 +   * entire DHCP process.

    23 +   */

    24 +

    25 +   struct irec *iface, *found;

    26 +   struct iname *if_tmp;

    27 +

    28 +   if (!daemon->if_names)

    29 +     return -1;

    30 +

    31 +   for (if_tmp = daemon->if_names; if_tmp; if_tmp = if_tmp->next)

    32 +     if (if_tmp->name && (!if_tmp->used || strchr(if_tmp->name, '*')))

    33 +       return -1;

    34 + 

    35 +   for (found = NULL, iface = daemon->interfaces; iface; iface = iface->next)

    36 +     if (iface->dhcp_ok)

    37 +       {

    38 +	 if (!found)

    39 +	   found = iface;

    40 +	 else if (strcmp(found->name, iface->name) != 0)

    41 +	   return -1; /* more than one. */

    42 +       }

    43 +

    44 +   if (found)

    45 +     return found->index;

    46 +

    47 +   return -1;

    48 +}

    49 +

    50 +void bindtoif(int ifindex, int fd, int is_dhcp6)

    51 +{

    52 +  if (is_dhcp6)

    53 +    {

    54 +      if (setsockopt(fd, IPPROTO_IPV6, IPV6_BOUND_IF, (char *)&ifindex, sizeof(ifindex)) == -1 && 

    55 +          errno != EPERM)

    56 +        die(_("failed to set IPv6_BOUND_IF on DHCP socket: %s"), NULL, EC_BADNET);

    57 +    }

    58 +  else

    59 +    {

    60 +      if (setsockopt(fd, IPPROTO_IP, IP_BOUND_IF, &ifindex, sizeof(ifindex)) == -1 &&

    61 +          errno != EPERM)

    62 +        die(_("failed to set IP_BOUND_IF on DHCP socket: %s"), NULL, EC_BADNET);

    63 +    }

    64 +}

    65  #endif

    66  

    67  static const struct opttab_t {

    68 --- dnsmasq-2.75/src/dnsmasq.h	2016-09-22 15:20:19.502011580 -0700

    69 +++ new/src/dnsmasq.h	2016-09-22 13:17:03.865473011 -0700

    70 @@ -1464,6 +1464,9 @@

    71  #ifdef HAVE_LINUX_NETWORK

    72  char *whichdevice(void);

    73  void bindtodevice(char *device, int fd);

    74 +#elif defined(HAVE_SOLARIS_NETWORK)

    75 +int which_ifindex(void);

    76 +void bindtoif(int ifindex, int fd, int is_dhcp6);

    77  #endif

    78  #  ifdef HAVE_DHCP6

    79  void display_opts6(void);

    80 --- dnsmasq-2.75/src/dnsmasq.c	2015-07-30 12:59:07.000000000 -0700

    81 +++ new/src/dnsmasq.c	2016-09-22 15:20:03.040122945 -0700

    82 @@ -54,6 +54,10 @@

    83    char *bound_device = NULL;

    84    int did_bind = 0;

    85  #endif 

    86 +#if defined(HAVE_SOLARIS_NETWORK)

    87 +  int bound_ifindex = -1;

    88 +  int did_bind = 0;

    89 +#endif

    90  #if defined(HAVE_DHCP) || defined(HAVE_DHCP6)

    91    struct dhcp_context *context;

    92    struct dhcp_relay *relay;

    93 @@ -306,6 +310,23 @@

    94  	      did_bind = 1;

    95  	    }

    96  	}

    97 +#elif defined(HAVE_SOLARIS_NETWORK) && defined(HAVE_DHCP)

    98 +      bound_ifindex = which_ifindex();

    99 +

   100 +      if (daemon->dhcp)

   101 +	{

   102 +          if (!daemon->relay4 && bound_ifindex >= 0)

   103 +            {

   104 +	      bindtoif(bound_ifindex, daemon->dhcpfd, 0);

   105 +	      did_bind = 1;

   106 +	    }

   107 +

   108 +	  if (daemon->enable_pxe && bound_ifindex >= 0)

   109 +	    {

   110 +              bindtoif(bound_ifindex, daemon->pxefd, 0);

   111 +	      did_bind = 1;

   112 +	    }

   113 +	}

   114  #endif

   115  

   116  #if defined(HAVE_LINUX_NETWORK) && defined(HAVE_DHCP6)

   117 @@ -314,6 +335,12 @@

   118  	  bindtodevice(bound_device, daemon->dhcp6fd);

   119  	  did_bind = 1;

   120  	}

   121 +#elif defined(HAVE_SOLARIS_NETWORK) && defined(HAVE_DHCP6)

   122 +      if (daemon->doing_dhcp6 && !daemon->relay6 && bound_ifindex >= 0)

   123 +	{

   124 +          bindtoif(bound_ifindex, daemon->dhcp6fd, 1);

   125 +	  did_bind = 1;

   126 +	}

   127  #endif

   128      }

   129    else 

   130 @@ -788,6 +815,9 @@

   131  #  ifdef HAVE_LINUX_NETWORK

   132    if (did_bind)

   133      my_syslog(MS_DHCP | LOG_INFO, _("DHCP, sockets bound exclusively to interface %s"), bound_device);

   134 +#  elif defined(HAVE_SOLARIS_NETWORK)

   135 +  if (did_bind)

   136 +    my_syslog(MS_DHCP | LOG_INFO, _("DHCP, sockets bound exclusively to interface index %d"), bound_ifindex);

   137  #  endif

   138  

   139    /* after dhcp_contruct_contexts */