iothconf

Internet of Threads (IoTh) stack configuration made easy peasy

iothconf can use four sources of data to configure an ioth stack:

• static data (IPv4 and/or IPv6)
• DHCP (IPv4, RFC 2131 and 6843)
• router discovery (IPv6, RFC 4861)
• DHCPv6 (IPv6, RFC 8415 and 4704)

The API of the iothconf library has three entries:

• ioth_config: configure the stack

     int ioth_config(struct ioth *stack, char *config);

• ioth_resolvconf: return a configuration string for the domain name resolution library (e.g. iothdns. The syntax of the configuration file is consistent with resolv.conf(5). (the string is dynamically allocated: use free(3) to deallocate it). It returns NULL and errno = 0 if nothing changed since the previous call. In case of error it returns NULL and errno != 0.

     char *ioth_resolvconf(struct ioth *stack, char *config);

• ioth_newstackc is a shortcut to create a stack and configure it. It is a shortcut call for ioth_newstack+ioth_config. It needs one string for the whole creation/configuration process. It permits to create stacks with zero or one interface (the most common scenario). It supports all the option of ioth_config plus stack=... to select the stack implementation and vnl=... to select the VDE network.

     struct ioth *ioth_newstackc(const char *stack_config);

Compile and Install

Pre-requisites: libioth.

iothconf uses cmake. The standard building/installing procedure is:

mkdir build
cd build
cmake ..
make
sudo make install

An uninstaller is provided for your convenience. In the build directory run:

sudo make uninstall

examples:

Create a new IoTh stack

...as described in libioth. The following example creates an IoTh stack with one interface connected to vxvde://234.0.0.2.

     struct ioth *stack = ioth_newstack("vdestack","vxvde://234.0.0.1");

Configure the stack:

• IPv4 set static IP and gateway

     ioth_config(stack, "eth,ip=10.0.0.1/24,gw=10.0.0.254");

• IPv4 dhcp

     ioth_config(stack, "eth,dhcp");

• IPv4 and IPv6 using all the available autoconfigurations and set the fully qualified domain name

     ioth_config(stack, "eth,dhcp,dhcp6,rd,fqdn=host.v2.cs.unibo.it");

• the same above using the shortcut auto ( = eth,dhcp,dhcp6,rd )

     ioth_config(stack, "auto,fqdn=host.v2.cs.unibo.it");

Create and configure the stack using one call and one configuration string:

     struct ioth *stack = ioth_newstackc("stack=vdestack,vnl=vxvde://234.0.0.1,eth,ip=10.0.0.1/24,gw=10.0.0.254");
     struct ioth *stack = ioth_newstackc("stack=vdestack,vnl=vxvde://234.0.0.1,eth,dhcp");
     struct ioth *stack = ioth_newstackc("stack=vdestack,vnl=vxvde://234.0.0.1,auto,fqdn=host.v2.cs.unibo.it");

Options supported by ioth_config and ioth_newstackc

• stack=...: (ioth_newstackc only) define the ip stack implementation
• vnl=...: (ioth_newstackc only) define the vde network to join
• iface=... : select the interface e.g. iface=eth0 (default value vde0)
• ifindex=... : id of the interface (it can be used instead of iface)
• fqdn=.... : set the fully qualified domain name for dhcp, dhcpv6 slaac-hash-autoconf
• mac=... : (or macaddr) define the macaddr for eth here below. (e.g. eth,mac=10:a1:b2:c3:d4:e5)
• eth : turn on the interface (and set the MAC address if requested or a hash based MAC address if fqdn is defined)
• dhcp : (or dhcp4 or dhcpv4) use dhcp (IPv4)
• dhcp6 : (or dhcpv6) use dhcpv6 (for IPv6)
• rd : (or rd6) use the router discovery protocol (IPv6)
• slaac : use stateless auto-configuration (IPv6) (requires rd)
• auto : shortcut for eth+dhcp+dhcp6+rd
• auto4 : (or autov4) shortcut for eth+dhcp
• auto6 : (or autov6) shortcut for eth+dhcp6+rd
• ip=..../.. : set a static address IPv4 or IPv6 and its prefix length example: ip=10.0.0.100/24 or ip=2001:760:1:2::100/64
• gw=..... : set a static default route IPv4 or IPv6
• dns=.... : set a static address for a DNS server
• domain=.... : set a static domain for the dns search
• debug : show the status of the current configuration parameters
• -static, -eth, -dhcp, -dhcp6, -rd, -auto, -auto4, -auto6 (and all the synonyms + a heading minus) clean (undo) the configuration

TODO: missing features

• thread option to start a thread for leases renewal.