ipcpd: Use the term "layer" and deprecate "shim"

This changes the terminology to use layer instead of DIF and deprecate
the word "shim" for the IPCPs that attach to Ethernet LLC and UDP .The
terminology has not yet been changed in the variable names etc.

This reflects the design choices in Ouroboros to make IPCPs pure
resource allocators instead of also providing an "IPC service". The
Ouroboros IPCPs that attach to Ethernet and UDP implement the
allocator and are thus not really shims.

Signed-off-by: Dimitri Staessens <dimitri.staessens@ugent.be>
Signed-off-by: Sander Vrijders <sander.vrijders@ugent.be>

25 files changed, 169 insertions, 175 deletions

diff --git a/doc/man/ouroboros-glossary.7 b/doc/man/ouroboros-glossary.7
index 5f9425f6..3b3e69f1 100644
--- a/doc/man/ouroboros-glossary.7
+++ b/doc/man/ouroboros-glossary.7
@@ -29,13 +29,13 @@ in the IRMd.
 .PP
 bootstrap
 .RS 4
-to configure an IPCP and start it as the first member of a DIF.
+to configure an IPCP and start it as the first member of a layer.
 .RE
 
 .PP
 congestion control
 .RS 4
-the mechanism by which a server DIF controls its resources and
+the mechanism by which a server layer controls its resources and
 prevents its client processes from sending more information than it
 can currently handle. This is orthogonal to flow control.
 .RE
@@ -49,17 +49,11 @@ Table.
 .RE
 
 .PP
-distributed IPC facility (DIF)
-.RS 4
-deprecate?
-.RE
-
-.PP
 enrolment
 .RS 4
-the action of connecting to a member of an existing DIF, retrieving
+the action of connecting to a member of an existing layer, retrieving
 the bootstrap information and starting the IPCP as a new member of
-that DIF.
+that layer.
 .RE
 
 .PP
diff --git a/doc/man/ouroboros-tutorial.7 b/doc/man/ouroboros-tutorial.7
index 8e135e23..a6f3eb4d 100644
--- a/doc/man/ouroboros-tutorial.7
+++ b/doc/man/ouroboros-tutorial.7
@@ -46,32 +46,32 @@ The output should be
 
 .SH PINGING A SERVER APPLICATION OVER THE LOOPBACK ADAPTER
 
-With a running irmd, let's create an IPC process. For this
-tutorial, we will create and bootstrap a shim-eth-llc shim IPCP over
-the loopback interface. To observe what's going on, open another
-terminal window. Note that "ipcp bootstrap" will create an IPCP if an
-IPCP by that name does not yet exist (See \fBouroboros\fR(8)).
+With a running irmd, let's create an IPC process. For this tutorial,
+we will create and bootstrap an eth-llc IPCP over the loopback
+interface. To observe what's going on, open another terminal
+window. Note that "ipcp bootstrap" will create an IPCP if an IPCP by
+that name does not yet exist (See \fBouroboros\fR(8)).
 
 .RS 4
-$ irm ipcp bootstrap type shim-eth-llc name shim dif llc if lo
+$ irm ipcp bootstrap type eth-llc name llc layer llc if lo
 .RE
 
 .RS 4
 ==23918== irmd(II): Created IPCP 23932.
 .br
-==23932== ipcpd/shim-eth-llc(II): Using raw socket device.
+==23932== ipcpd/eth-llc(II): Using raw socket device.
 .br
-==23918== irmd(II): Bootstrapped IPCP 23932 in DIF llc.
+==23918== irmd(II): Bootstrapped IPCP 23932 in layer llc.
 .RE
 
-Now that we have a shim IPCP bootstrapped, it can act as a local
-network that can provide full connectivity between all processes in
-the system. Let's test it using the oping application. First, let's
-choose a name for the server ("my.oping.server") and register in the
-shim DIF.
+Now that we have the IPCP bootstrapped, it can act as a local network
+layer that can provide full connectivity between all processes in the
+system. Let's test it using the oping application. First, let's choose
+a name for the server ("my.oping.server") and register in the llc
+layer.
 
 .RS 4
-$ irm reg name my.oping.server dif llc
+$ irm reg name my.oping.server layer llc
 .RE
 
 The IRMd should respond with
diff --git a/doc/man/ouroboros.8 b/doc/man/ouroboros.8
index b81c25a0..04d0990d 100644
--- a/doc/man/ouroboros.8
+++ b/doc/man/ouroboros.8
@@ -73,33 +73,34 @@ be bound to multiple names.
 
 \fBCreating an IPC Process\fR will instantiate a new IPCP in the
 system. This IPCP will be empty, with only a name and type specified,
-and ready for either \fIbootstrapping\fR into a new DIF (or a new or
-existing shim DIF) or \fIenrolling\fR in an existing DIF.
+and ready for either \fIbootstrapping\fR into a new layer or
+\fIenrolling\fR in an existing layer.
 
 \fBBootstrapping an IPC Process\fR gives it the necessary information
-from the command line to start operating as a \fIDIF\fR. Each IPCP
+from the command line to start operating as a \fIlayer\fR. Each IPCP
 type has its own set of configuration options.
 
-\fBEnrolling an IPC Process\fR in a DIF configures it by contacting
-another IPCP that is already a member of that DIF (bootstrapped or
+\fBEnrolling an IPC Process\fR in a layer configures it by contacting
+another IPCP that is already a member of that layer (bootstrapped or
 enrolled). After \fIenrollment\fR, the IPCP is configured, and may or
-may not have connections to the DIF.
+may not have connections to the layer.
 
-\fBRegistering a name in a DIF\fR inserts the name in that \fIDIF\fR's
-\fIdirectory\fR.  Once a name is \fIregistered\fR in a DIF, the name
-can be used as a destination handle for \fIflow allocation\fR.
+\fBRegistering a name in a layer\fR inserts the name in that
+\fIlayer\fR's \fIdirectory\fR.  Once a name is \fIregistered\fR in a
+layer, the name can be used as a destination handle for \fIflow
+allocation\fR.
 
 Ouroboros normal IPCPs are just like any other process, and will need
-to be bound and registered in a lower-rank DIF before they can be
+to be bound and registered in a lower-rank layer before they can be
 accessed by other processes.
 
-In order to enroll an IPC process in a DIF, some other member will
-have to be reachable over a lower DIF. Shim IPCPs are all bootstrapped
-and thus need not enroll as they work directly over a physical
-connection. Ouroboros currently supports shim IPCPs over shared memory
-(local), L1 (raptor, experimental), L2 (shim-eth-llc) and L3
-(shim-udp). The normal DIF requires connections to be established
-between IPCP components for its operation.
+In order to enroll an IPC process in a layer, some other member will
+have to be reachable over a lower layer. IPCPs that wrap a legacy
+transmission technology are all bootstrapped and thus need not enroll
+as they work directly over a physical connection. Ouroboros currently
+supports IPCPs over shared memory (local), L1 (raptor, experimental),
+L2 (eth-llc) and L3 (udp). The normal layer requires connections to be
+established between IPCP components for its operation.
 
 \fBConnecting the management components\fR using \fImanagement
 flows\fR allows management information to be sent between IPCPs so
@@ -119,15 +120,15 @@ that rely on data transfer flows are the \fIdirectory\fR and the
 creates an IPCP process of type \fItype\fR in the system with name
 \fIname\fR. Allowable values for \fItype\fR are:
 .PP
-\fBlocal\fR        - create a loopback IPCP.
+\fBlocal\fR    - create a loopback IPCP.
 .PP
-\fBraptor\fR       - create an IPCP that attaches to a raptor NetFPGA device.
+\fBraptor\fR   - create an IPCP that attaches to a raptor NetFPGA device.
 .PP
-\fBshim-eth-llc\fR - create an IPCP that attaches to an Ethernet adapter.
+\fBeth-llc\fR  - create an IPCP that attaches to an Ethernet adapter.
 .PP
-\fBshim-udp\fR     - create an IPCP that attaches to a UDP socket.
+\fBsudp\fR     - create an IPCP that attaches to a UDP socket.
 .PP
-\fBnormal\fR       - create a normal IPCP that uses lower level DIFs.
+\fBnormal\fR   - create a normal IPCP that uses lower level layers.
 .RE
 
 .PP
@@ -136,12 +137,12 @@ creates an IPCP process of type \fItype\fR in the system with name
 destroys the IPCP process with name \fIname\fR.
 .RE
 .PP
-\fBirm ipcp bootstrap\fR type \fItype\fR name \fIname\fR dif \fIdif\fR \
+\fBirm ipcp bootstrap\fR type \fItype\fR name \fIname\fR layer \fIlayer\fR \
 [\fIparams\fR] [\fIautobind\fR]
 .RS 4
 bootstraps an IPCP process of type \fItype\fR and name \fIname\fR in a
-DIF \fIdif\fR. If an IPCP with that name does not exist yet, the IPCP
-will be created.
+layer \fIlayer\fR. If an IPCP with that name does not exist yet, the
+IPCP will be created.
 .PP
 Values for [\fIparam\fR] are dependent on \fItype\fR:
 .PP
@@ -162,9 +163,9 @@ Values for [\fIparam\fR] are dependent on \fItype\fR:
 .RE
 
 .PP
-\fBshim-eth-llc\fR
+\fBeth-llc\fR
 .RS 4
-if_name \fIinterface\fR specifies the interface to bind the shim to.
+if_name \fIinterface\fR specifies the interface to bind the IPCP to.
 .PP
 [hash \fIpolicy\fR] specifies the hash function used for the directory,
 .br
@@ -172,7 +173,7 @@ if_name \fIinterface\fR specifies the interface to bind the shim to.
 .RE
 
 .PP
-\fBshim-udp\fR
+\fBudp\fR
 .RS 4
 ip \fIip\fR specifies the local IP address to bind to
 
@@ -218,17 +219,17 @@ default: simple.
 .br
 default: SHA3_256.
 .PP
-[autobind] will automatically bind a normal IPCP to its name and the DIF name.
+[autobind] will automatically bind a normal IPCP to its name and the layer name.
 .RE
 .RE
 
 .PP
-\fBirm ipcp enroll\fR name \fIname\fR dif \fIdif\fR [\fIautobind\fR]
+\fBirm ipcp enroll\fR name \fIname\fR layer \fIlayer\fR [\fIautobind\fR]
 .RS 4
-enrolls a normal IPCP \fIname\fR to a dif for which the IPCPs accept flows for
+enrolls a normal IPCP \fIname\fR to a layer for which the IPCPs accept flows for
 \fIname\fR.
 .PP
-[autobind] will automatically bind this IPCP to its name and the DIF name.
+[autobind] will automatically bind this IPCP to its name and the layer name.
 .RE
 
 \fBirm ipcp connect\fR name \fIname\fR component \fIcomponent\fR dst
@@ -236,7 +237,7 @@ enrolls a normal IPCP \fIname\fR to a dif for which the IPCPs accept flows for
 .RS 4
 connects a \fIcomponent\fR (\fBdt\fR or \fBmgmt\fR) of a normal IPCP
 with name \fIname\fR to that component of the destination IPCP within the
-same DIF.
+same layer.
 .RE
 
 \fBirm ipcp disconnect\fR name \fIname\fR component \fIcomponent\fR dst
@@ -244,7 +245,7 @@ same DIF.
 .RS 4
 disconnects \fIcomponent\fR (\fBdt\fR or \fBmgmt\fR) of a normal IPCP
 with name \fIname\fR from that component of the destination IPCP within the
-same DIF.
+same layer.
 .RE
 .RE
 
@@ -256,7 +257,7 @@ same DIF.
 bind a program \fIprogram\fR, referenced by its binary, to a certain
 name. The binary can be specified by an absolute or relative path, and
 will be searched for in all directories specified in the \fBPATH\fR
-variable. If \fIname\fR is registered in a DIF, all instances of
+variable. If \fIname\fR is registered in a layer, all instances of
 \fIprogram\fR will accept flows for \fIname\fR. If the \fIauto\fR
 keyword is specified, the IRMd will start instances if there are no
 readily available instances when a new flow is requested and any
@@ -268,14 +269,14 @@ application when it is started.
 \fBirm bind\fR process \fIpid\fR name \fIname\fR
 .RS 4
 bind a process \fIpid\fR to a certain name. If \fIname\fR is registered
-in a DIF, the process \fIpid\fR will accept flows for that name.
+in a layer, the process \fIpid\fR will accept flows for that name.
 .RE
 
 .PP
 \fBirm bind\fR ipcp \fIipcp\fR name \fIname\fR
 .RS 4
 bind an IPCP \fIipcp\fR to a \fIname\fR. If \fIname\fR is registered
-in a DIF, \fIipcp\fR will accept flows for \fIname\fR. This is a
+in a layer, \fIipcp\fR will accept flows for \fIname\fR. This is a
 shorthand for binding the pid of \fipcp\fR.
 .RE
 
@@ -303,15 +304,15 @@ not accept future flow allocation requests for \fIname\fR.
 .RE
 
 .PP
-\fBirm reg\fR name \fIname\fR dif \fIdif\fR [dif \fIdif\fR ...]
+\fBirm reg\fR name \fIname\fR layer \fIlayer\fR [layer \fIlayer\fR ...]
 .RS 4
-Register name \fIname\fR in difs \fIdif\fR.
+Register name \fIname\fR in layers \fIlayer\fR.
 .RE
 
 .PP
-\fBirm unreg\fR name \fIname\fR dif \fIdif\fR [dif \fIdif\fR ...]
+\fBirm unreg\fR name \fIname\fR layer \fIlayer\fR [layer \fIlayer\fR ...]
 .RS 4
-Unregister name \fIname\fR in difs \fIdif\fR.
+Unregister name \fIname\fR in layers \fIlayer\fR.
 .RE
 
 .SH TERMINOLOGY
diff --git a/include/ouroboros/ipcp.h b/include/ouroboros/ipcp.h
index 2be654ea..210c38cf 100644
--- a/include/ouroboros/ipcp.h
+++ b/include/ouroboros/ipcp.h
@@ -27,7 +27,7 @@
 #include <unistd.h>
 #include <stdbool.h>
 
-#define DIF_NAME_SIZE 256
+#define LAYER_NAME_SIZE 256
 
 /*
  * NOTE: the IRMd uses this order to select an IPCP
@@ -37,8 +37,8 @@ enum ipcp_type {
         IPCP_LOCAL = 0,
         IPCP_NORMAL,
         IPCP_RAPTOR,
-        IPCP_SHIM_ETH_LLC,
-        IPCP_SHIM_UDP
+        IPCP_ETH_LLC,
+        IPCP_UDP
 };
 
 /* Normal IPCP policies */
@@ -63,9 +63,9 @@ enum pol_dir_hash {
         DIR_HASH_SHA3_512
 };
 
-/* Info reported back to the IRMd about the DIF on enrollment */
+/* Info reported back to the IRMd about the layer on enrollment */
 struct dif_info {
-        char dif_name[DIF_NAME_SIZE];
+        char dif_name[LAYER_NAME_SIZE];
         int  dir_hash_algo;
 };
 
@@ -84,11 +84,11 @@ struct ipcp_config {
         enum pol_routing   routing_type;
         enum pol_pff       pff_type;
 
-        /* Shim UDP */
+        /* UDP */
         uint32_t           ip_addr;
         uint32_t           dns_addr;
 
-        /* Shim Ethernet LLC */
+        /* Ethernet LLC */
         char *             if_name;
 };
 
diff --git a/src/ipcpd/CMakeLists.txt b/src/ipcpd/CMakeLists.txt
index f43dba65..67d9fccf 100644
--- a/src/ipcpd/CMakeLists.txt
+++ b/src/ipcpd/CMakeLists.txt
@@ -34,8 +34,8 @@ set(IPCP_SOURCES
 add_subdirectory(local)
 add_subdirectory(normal)
 add_subdirectory(raptor)
-add_subdirectory(shim-udp)
-add_subdirectory(shim-eth-llc)
+add_subdirectory(udp)
+add_subdirectory(eth-llc)
 
 configure_file("${CMAKE_CURRENT_SOURCE_DIR}/config.h.in"
   "${CMAKE_CURRENT_BINARY_DIR}/config.h" @ONLY)
diff --git a/src/ipcpd/config.h.in b/src/ipcpd/config.h.in
index 322c6856..0c0e2922 100644
--- a/src/ipcpd/config.h.in
+++ b/src/ipcpd/config.h.in
@@ -45,12 +45,12 @@
 #define IPCP_SCHED_THR_MUL  @IPCP_SCHED_THR_MUL@
 #define PFT_SIZE            @PFT_SIZE@
 
-/* shim-udp */
+/* udp */
 #cmakedefine HAVE_DDNS
 #define NSUPDATE_EXEC       "@NSUPDATE_EXECUTABLE@"
 #define NSLOOKUP_EXEC       "@NSLOOKUP_EXECUTABLE@"
 
-/* shim-eth-llc */
+/* eth-llc */
 #cmakedefine HAVE_NETMAP
 #cmakedefine HAVE_BPF
 #cmakedefine HAVE_RAW_SOCKETS
diff --git a/src/ipcpd/shim-eth-llc/CMakeLists.txt b/src/ipcpd/eth-llc/CMakeLists.txt
index e1eea2b5..11a631b3 100644
--- a/src/ipcpd/shim-eth-llc/CMakeLists.txt
+++ b/src/ipcpd/eth-llc/CMakeLists.txt
@@ -21,13 +21,13 @@ mark_as_advanced(NETMAP_C_INCLUDE_DIR)
 
 if (CMAKE_SYSTEM_NAME STREQUAL "Linux")
   set(DISABLE_RAW_SOCKETS FALSE CACHE BOOL
-    "Disable raw socket support for LLC shim")
+    "Disable raw socket support for LLC IPCP")
   if (NOT DISABLE_RAW_SOCKETS)
-    message(STATUS "Raw socket support for shim-eth-llc enabled")
+    message(STATUS "Raw socket support for eth-llc enabled")
     set(HAVE_RAW_SOCKETS TRUE PARENT_SCOPE)
     set(HAVE_LLC TRUE)
   else ()
-    message(STATUS "Raw socket support for shim-eth-llc disabled by user")
+    message(STATUS "Raw socket support for eth-llc disabled by user")
     unset(HAVE_RAW_SOCKETS)
     unset(HAVE_LLC)
   endif ()
@@ -43,15 +43,15 @@ if (NOT CMAKE_SYSTEM_NAME STREQUAL "Linux")
 
   if (BPF_C_INCLUDE_DIR)
     set(DISABLE_BPF FALSE CACHE BOOL
-      "Disable Berkeley Packet Filter support for LLC shim")
+      "Disable Berkeley Packet Filter support for LLC IPCP")
     if (NOT DISABLE_BPF)
       message(STATUS "Berkeley Packet Filter support "
-                     "for shim-eth-llc enabled")
+                     "for eth-llc enabled")
       set(HAVE_BPF TRUE PARENT_SCOPE)
       set(HAVE_LLC TRUE)
     else ()
       message(STATUS "Berkeley Packet Filter support "
-                     "for shim-eth-llc disabled by user")
+                     "for eth-llc disabled by user")
       unset(HAVE_BPF)
       unset(HAVE_LLC)
     endif ()
@@ -60,47 +60,47 @@ endif ()
 
 if (NETMAP_C_INCLUDE_DIR)
   set(DISABLE_NETMAP FALSE CACHE BOOL
-      "Disable netmap support for LLC shim")
+      "Disable netmap support for LLC IPCP")
   if (NOT DISABLE_NETMAP)
-    message(STATUS "Netmap support for shim-eth-llc enabled")
+    message(STATUS "Netmap support for eth-llc enabled")
     set(HAVE_NETMAP TRUE PARENT_SCOPE)
     test_and_set_c_compiler_flag_global(-std=c99)
     set(HAVE_LLC TRUE)
   else ()
-    message(STATUS "Netmap support for shim-eth-llc disabled by user")
+    message(STATUS "Netmap support for eth-llc disabled by user")
     unset(HAVE_NETMAP)
     unset(HAVE_LLC)
-    unset(IPCP_SHIM_ETH_LLC_TARGET CACHE)
+    unset(IPCP_ETH_LLC_TARGET CACHE)
   endif ()
 endif ()
 
 if (HAVE_LLC)
-  message(STATUS "Supported raw Ethernet API found, building shim-eth-llc")
+  message(STATUS "Supported raw Ethernet API found, building eth-llc")
 
-  set(SHIM_ETH_LLC_SOURCES
+  set(ETH_LLC_SOURCES
     # Add source files here
     ${CMAKE_CURRENT_SOURCE_DIR}/main.c
   )
 
-  set(IPCP_SHIM_ETH_LLC_TARGET ipcpd-shim-eth-llc CACHE INTERNAL "")
+  set(IPCP_ETH_LLC_TARGET ipcpd-eth-llc CACHE INTERNAL "")
 
-  add_executable(ipcpd-shim-eth-llc ${SHIM_ETH_LLC_SOURCES} ${IPCP_SOURCES})
+  add_executable(ipcpd-eth-llc ${ETH_LLC_SOURCES} ${IPCP_SOURCES})
 
   if (HAVE_BPF AND NOT APPLE)
-    target_include_directories(ipcpd-shim-eth-llc PUBLIC ${BPF_C_INCLUDE_DIR})
+    target_include_directories(ipcpd-eth-llc PUBLIC ${BPF_C_INCLUDE_DIR})
   endif ()
 
   if (HAVE_NETMAP AND NOT APPLE)
-    target_include_directories(ipcpd-shim-eth-llc PUBLIC
+    target_include_directories(ipcpd-eth-llc PUBLIC
       ${NETMAP_C_INCLUDE_DIR})
   endif ()
 
-  target_link_libraries(ipcpd-shim-eth-llc LINK_PUBLIC ouroboros-dev)
+  target_link_libraries(ipcpd-eth-llc LINK_PUBLIC ouroboros-dev)
 
   include(AddCompileFlags)
   if (CMAKE_BUILD_TYPE MATCHES "Debug*")
-    add_compile_flags(ipcpd-shim-eth-llc -DCONFIG_OUROBOROS_DEBUG)
+    add_compile_flags(ipcpd-eth-llc -DCONFIG_OUROBOROS_DEBUG)
   endif ()
 
-  install(TARGETS ipcpd-shim-eth-llc RUNTIME DESTINATION sbin)
+  install(TARGETS ipcpd-eth-llc RUNTIME DESTINATION sbin)
 endif ()
diff --git a/src/ipcpd/shim-eth-llc/main.c b/src/ipcpd/eth-llc/main.c
index 3fec7c3d..105058d3 100644
--- a/src/ipcpd/shim-eth-llc/main.c
+++ b/src/ipcpd/eth-llc/main.c
@@ -1,7 +1,7 @@
 /*
  * Ouroboros - Copyright (C) 2016 - 2017
  *
- * Shim IPC process over Ethernet with LLC
+ * IPC process over Ethernet with LLC
  *
  *    Dimitri Staessens <dimitri.staessens@ugent.be>
  *    Sander Vrijders   <sander.vrijders@ugent.be>
@@ -31,7 +31,7 @@
 
 #include "config.h"
 
-#define OUROBOROS_PREFIX "ipcpd/shim-eth-llc"
+#define OUROBOROS_PREFIX "ipcpd/eth-llc"
 
 #include <ouroboros/hash.h>
 #include <ouroboros/errno.h>
@@ -91,7 +91,7 @@
 #include <net/bpf.h>
 #endif
 
-#define THIS_TYPE                 IPCP_SHIM_ETH_LLC
+#define THIS_TYPE                 IPCP_ETH_LLC
 
 #define MGMT_SAP                  0x01
 #define MAC_SIZE                  6
@@ -1109,7 +1109,7 @@ static int eth_llc_ipcp_bootstrap(const struct ipcp_config * conf)
                 goto fail_sdu_writer;
         }
 
-        log_dbg("Bootstrapped shim IPCP over Ethernet with LLC with pid %d.",
+        log_dbg("Bootstrapped IPCP over Ethernet with LLC with pid %d.",
                 getpid());
 
         return 0;
@@ -1370,7 +1370,7 @@ int main(int    argc,
                 goto fail_init;
 
         if (eth_llc_data_init() < 0) {
-                log_err("Failed to init shim-eth-llc data.");
+                log_err("Failed to init eth-llc data.");
                 goto fail_data_init;
         }
 
diff --git a/src/ipcpd/ipcp.c b/src/ipcpd/ipcp.c
index 84c42b98..c6e819bb 100644
--- a/src/ipcpd/ipcp.c
+++ b/src/ipcpd/ipcp.c
@@ -245,10 +245,10 @@ static void * mainloop(void * o)
                                 conf.pff_type       = conf_msg->pff_type;
                         }
 
-                        if (conf_msg->ipcp_type == IPCP_SHIM_ETH_LLC)
+                        if (conf_msg->ipcp_type == IPCP_ETH_LLC)
                                 conf.if_name        = conf_msg->if_name;
 
-                        if (conf_msg->ipcp_type == IPCP_SHIM_UDP) {
+                        if (conf_msg->ipcp_type == IPCP_UDP) {
                                 conf.ip_addr  = conf_msg->ip_addr;
                                 conf.dns_addr = conf_msg->dns_addr;
 
@@ -256,8 +256,8 @@ static void * mainloop(void * o)
                                 dif_info.dir_hash_algo      = HASH_MD5;
                         }
 
-                        /* Only shim-udp needs a fixed hash algorithm */
-                        if (conf_msg->ipcp_type != IPCP_SHIM_UDP) {
+                        /* Only udp needs a fixed hash algorithm */
+                        if (conf_msg->ipcp_type != IPCP_UDP) {
                                 switch(conf_msg->dif_info->dir_hash_algo) {
                                 case DIR_HASH_SHA3_224:
                                         conf.dif_info.dir_hash_algo =
diff --git a/src/ipcpd/local/CMakeLists.txt b/src/ipcpd/local/CMakeLists.txt
index 422fa709..ab416c61 100644
--- a/src/ipcpd/local/CMakeLists.txt
+++ b/src/ipcpd/local/CMakeLists.txt
@@ -14,11 +14,11 @@ include_directories(${CMAKE_BINARY_DIR}/include)
 
 set(IPCP_LOCAL_TARGET ipcpd-local CACHE INTERNAL "")
 
-set(SHIM_LOCAL_SOURCES
+set(LOCAL_SOURCES
   # Add source files here
   ${CMAKE_CURRENT_SOURCE_DIR}/main.c)
 
-add_executable(ipcpd-local ${SHIM_LOCAL_SOURCES} ${IPCP_SOURCES})
+add_executable(ipcpd-local ${LOCAL_SOURCES} ${IPCP_SOURCES})
 target_link_libraries(ipcpd-local LINK_PUBLIC ouroboros-common ouroboros-dev)
 
 include(AddCompileFlags)
diff --git a/src/ipcpd/normal/main.c b/src/ipcpd/normal/main.c
index 772b5792..401c1578 100644
--- a/src/ipcpd/normal/main.c
+++ b/src/ipcpd/normal/main.c
@@ -55,7 +55,7 @@ static int initialize_components(const struct ipcp_config * conf)
 {
         ipcpi.dif_name = strdup(conf->dif_info.dif_name);
         if (ipcpi.dif_name == NULL) {
-                log_err("Failed to set DIF name.");
+                log_err("Failed to set layer name.");
                 goto fail_dif_name;
         }
 
@@ -263,7 +263,7 @@ static int normal_ipcp_bootstrap(const struct ipcp_config * conf)
                 goto fail_bootstrap;
         }
 
-        log_dbg("Bootstrapped in DIF %s.", conf->dif_info.dif_name);
+        log_dbg("Bootstrapped in layer %s.", conf->dif_info.dif_name);
 
         return 0;
 
diff --git a/src/ipcpd/normal/pol/flat.c b/src/ipcpd/normal/pol/flat.c
index c52ebe38..49525994 100644
--- a/src/ipcpd/normal/pol/flat.c
+++ b/src/ipcpd/normal/pol/flat.c
@@ -39,7 +39,6 @@
 #include <assert.h>
 
 #define NAME_LEN 8
-#define REC_DIF_SIZE 10000
 
 struct {
         uint8_t addr_size;
diff --git a/src/ipcpd/shim-udp/CMakeLists.txt b/src/ipcpd/udp/CMakeLists.txt
index aaf7e83b..20c1b58e 100644
--- a/src/ipcpd/shim-udp/CMakeLists.txt
+++ b/src/ipcpd/udp/CMakeLists.txt
@@ -12,14 +12,14 @@ include_directories(${CURRENT_BINARY_PARENT_DIR})
 include_directories(${CMAKE_SOURCE_DIR}/include)
 include_directories(${CMAKE_BINARY_DIR}/include)
 
-set(IPCP_SHIM_UDP_TARGET ipcpd-shim-udp CACHE INTERNAL "")
+set(IPCP_UDP_TARGET ipcpd-udp CACHE INTERNAL "")
 
-set(SHIM_UDP_SOURCES
+set(UDP_SOURCES
   # Add source files here
   ${CMAKE_CURRENT_SOURCE_DIR}/main.c)
 
-add_executable(ipcpd-shim-udp ${SHIM_UDP_SOURCES} ${IPCP_SOURCES})
-target_link_libraries(ipcpd-shim-udp LINK_PUBLIC ouroboros-dev)
+add_executable(ipcpd-udp ${UDP_SOURCES} ${IPCP_SOURCES})
+target_link_libraries(ipcpd-udp LINK_PUBLIC ouroboros-dev)
 
 # Find the nsupdate executable
 find_program(NSUPDATE_EXECUTABLE
@@ -54,7 +54,7 @@ endif ()
 
 include(AddCompileFlags)
 if (CMAKE_BUILD_TYPE MATCHES "Debug*")
-  add_compile_flags(ipcpd-shim-udp -DCONFIG_OUROBOROS_DEBUG)
+  add_compile_flags(ipcpd-udp -DCONFIG_OUROBOROS_DEBUG)
 endif ()
 
-install(TARGETS ipcpd-shim-udp RUNTIME DESTINATION sbin)
+install(TARGETS ipcpd-udp RUNTIME DESTINATION sbin)
diff --git a/src/ipcpd/shim-udp/main.c b/src/ipcpd/udp/main.c
index 79d5ea83..c54e6624 100644
--- a/src/ipcpd/shim-udp/main.c
+++ b/src/ipcpd/udp/main.c
@@ -1,7 +1,7 @@
 /*
  * Ouroboros - Copyright (C) 2016 - 2017
  *
- * Shim IPC process over UDP
+ * IPC process over UDP
  *
  *    Dimitri Staessens <dimitri.staessens@ugent.be>
  *    Sander Vrijders   <sander.vrijders@ugent.be>
@@ -24,7 +24,7 @@
 
 #include "config.h"
 
-#define OUROBOROS_PREFIX "ipcpd/shim-udp"
+#define OUROBOROS_PREFIX "ipcpd/udp"
 
 #include <ouroboros/hash.h>
 #include <ouroboros/list.h>
@@ -53,7 +53,7 @@
 #define FLOW_REQ              1
 #define FLOW_REPLY            2
 
-#define THIS_TYPE             IPCP_SHIM_UDP
+#define THIS_TYPE             IPCP_UDP
 #define LISTEN_PORT           htons(0x0D1F)
 #define SHIM_UDP_BUF_SIZE     256
 #define SHIM_UDP_MSG_SIZE     256
@@ -638,7 +638,7 @@ static int ipcp_udp_bootstrap(const struct ipcp_config * conf)
                 goto fail_sduloop;
         }
 
-        log_dbg("Bootstrapped shim IPCP over UDP with pid %d.", getpid());
+        log_dbg("Bootstrapped IPCP over UDP with pid %d.", getpid());
         log_dbg("Bound to IP address %s.", ipstr);
         log_dbg("DNS server address is %s.", dnsstr);
 
@@ -1124,7 +1124,7 @@ int main(int    argc,
         }
 
         if (udp_data_init() < 0) {
-                log_err("Failed to init shim-udp data.");
+                log_err("Failed to init udp data.");
                 ipcp_create_r(getpid(), -1);
                 ipcp_fini();
                 exit(EXIT_FAILURE);
diff --git a/src/irmd/config.h.in b/src/irmd/config.h.in
index 83e59375..e6821256 100644
--- a/src/irmd/config.h.in
+++ b/src/irmd/config.h.in
@@ -20,8 +20,8 @@
  * Foundation, Inc., http://www.fsf.org/about/contact/.
  */
 
-#define IPCP_SHIM_UDP_EXEC      "@IPCP_SHIM_UDP_TARGET@"
-#define IPCP_SHIM_ETH_LLC_EXEC  "@IPCP_SHIM_ETH_LLC_TARGET@"
+#define IPCP_UDP_EXEC           "@IPCP_UDP_TARGET@"
+#define IPCP_ETH_LLC_EXEC       "@IPCP_ETH_LLC_TARGET@"
 #define IPCP_NORMAL_EXEC        "@IPCP_NORMAL_TARGET@"
 #define IPCP_LOCAL_EXEC         "@IPCP_LOCAL_TARGET@"
 #define IPCP_RAPTOR_EXEC        "@IPCP_RAPTOR_TARGET@"
diff --git a/src/irmd/ipcp.c b/src/irmd/ipcp.c
index dfb7c96b..60bf3512 100644
--- a/src/irmd/ipcp.c
+++ b/src/irmd/ipcp.c
@@ -139,11 +139,11 @@ pid_t ipcp_create(const char *   name,
         case IPCP_NORMAL:
                 exec_name = IPCP_NORMAL_EXEC;
                 break;
-        case IPCP_SHIM_UDP:
-                exec_name = IPCP_SHIM_UDP_EXEC;
+        case IPCP_UDP:
+                exec_name = IPCP_UDP_EXEC;
                 break;
-        case IPCP_SHIM_ETH_LLC:
-                exec_name = IPCP_SHIM_ETH_LLC_EXEC;
+        case IPCP_ETH_LLC:
+                exec_name = IPCP_ETH_LLC_EXEC;
                 break;
         case IPCP_LOCAL:
                 exec_name = IPCP_LOCAL_EXEC;
diff --git a/src/irmd/main.c b/src/irmd/main.c
index 7b4ad9d8..eb10cc4f 100644
--- a/src/irmd/main.c
+++ b/src/irmd/main.c
@@ -502,7 +502,7 @@ static int bootstrap_ipcp(pid_t               pid,
         entry->dif_name = strdup(info.dif_name);
         if (entry->dif_name == NULL) {
                 pthread_rwlock_unlock(&irmd.reg_lock);
-                log_warn("Failed to set name of DIF.");
+                log_warn("Failed to set name of layer.");
                 return -ENOMEM;
         }
 
@@ -510,7 +510,7 @@ static int bootstrap_ipcp(pid_t               pid,
 
         pthread_rwlock_unlock(&irmd.reg_lock);
 
-        log_info("Bootstrapped IPCP %d in DIF %s.",
+        log_info("Bootstrapped IPCP %d in layer %s.",
                  pid, conf->dif_info->dif_name);
 
         return 0;
@@ -564,7 +564,7 @@ static int enroll_ipcp(pid_t  pid,
 
         pthread_rwlock_unlock(&irmd.reg_lock);
 
-        log_info("Enrolled IPCP %d in DIF %s.",
+        log_info("Enrolled IPCP %d in layer %s.",
                  pid, info.dif_name);
 
         return 0;
diff --git a/src/irmd/registry.h b/src/irmd/registry.h
index f1f52b9e..6757b0ad 100644
--- a/src/irmd/registry.h
+++ b/src/irmd/registry.h
@@ -55,7 +55,7 @@ struct reg_entry {
         struct list_head    next;
         char *              name;
 
-        /* DIFs in which this name is registered */
+        /* layers in which this name is registered */
         struct list_head    difs;
         /* Programs that can be instantiated by the irmd */
         struct list_head    reg_progs;
diff --git a/src/lib/ipcp_config.proto b/src/lib/ipcp_config.proto
index aa2803f3..1ee1edcc 100644
--- a/src/lib/ipcp_config.proto
+++ b/src/lib/ipcp_config.proto
@@ -37,9 +37,9 @@ message ipcp_config_msg {
         optional uint32 addr_auth_type =  6;
         optional uint32 routing_type   =  7;
         optional uint32 pff_type       =  8;
-        // Config for shim UDP
+        // Config for UDP
         optional uint32 ip_addr        =  9;
         optional uint32 dns_addr       = 10;
-        // Config for the shim Ethernet LLC
+        // Config for the Ethernet LLC
         optional string if_name        = 11;
 }
diff --git a/src/lib/irm.c b/src/lib/irm.c
index fa0db727..c7a19707 100644
--- a/src/lib/irm.c
+++ b/src/lib/irm.c
@@ -130,7 +130,7 @@ int irm_bootstrap_ipcp(pid_t                      pid,
                 config.pff_type           = conf->pff_type;
                 dif_info.dir_hash_algo    = conf->dif_info.dir_hash_algo;
                 break;
-        case IPCP_SHIM_UDP:
+        case IPCP_UDP:
                 config.has_ip_addr  = true;
                 config.ip_addr      = conf->ip_addr;
                 config.has_dns_addr = true;
@@ -139,7 +139,7 @@ int irm_bootstrap_ipcp(pid_t                      pid,
         case IPCP_LOCAL:
         case IPCP_RAPTOR:
                 break;
-        case IPCP_SHIM_ETH_LLC:
+        case IPCP_ETH_LLC:
                 config.if_name = conf->if_name;
                 break;
         default:
diff --git a/src/tools/irm/irm_ipcp_bootstrap.c b/src/tools/irm/irm_ipcp_bootstrap.c
index 66bb96ce..2dc6f5f6 100644
--- a/src/tools/irm/irm_ipcp_bootstrap.c
+++ b/src/tools/irm/irm_ipcp_bootstrap.c
@@ -50,8 +50,8 @@
 #include "irm_utils.h"
 
 #define NORMAL                 "normal"
-#define SHIM_UDP               "shim-udp"
-#define SHIM_ETH_LLC           "shim-eth-llc"
+#define UDP                    "udp"
+#define ETH_LLC                "eth-llc"
 #define LOCAL                  "local"
 #define RAPTOR                 "raptor"
 
@@ -79,10 +79,10 @@ static void usage(void)
         /* FIXME: Add ipcp_config stuff */
         printf("Usage: irm ipcp bootstrap\n"
                "                name <ipcp name>\n"
-               "                dif <DIF name>\n"
+               "                layer <layer name>\n"
                "                type [TYPE]\n"
                "where TYPE = {" NORMAL " " LOCAL " "
-               SHIM_UDP " " SHIM_ETH_LLC " " RAPTOR "},\n\n"
+               UDP " " ETH_LLC " " RAPTOR "},\n\n"
                "if TYPE == " NORMAL "\n"
                "                [addr <address size> (default: %d)]\n"
                "                [fd <fd size> (default: %d)]\n"
@@ -98,11 +98,11 @@ static void usage(void)
                "      PFF_POLICY = {" SIMPLE_PFF " " ALTERNATE_PFF "}\n"
                "      ALGORITHM = {" SHA3_224 " " SHA3_256 " "
                SHA3_384 " " SHA3_512 "}\n\n"
-               "if TYPE == " SHIM_UDP "\n"
+               "if TYPE == " UDP "\n"
                "                ip <IP address in dotted notation>\n"
                "                [dns <DDNS IP address in dotted notation>"
                " (default: none)]\n\n"
-               "if TYPE == " SHIM_ETH_LLC "\n"
+               "if TYPE == " ETH_LLC "\n"
                "                if_name <interface name>\n"
                "                [hash [ALGORITHM] (default: %s)]\n"
                "where ALGORITHM = {" SHA3_224 " " SHA3_256 " "
@@ -148,7 +148,7 @@ int do_bootstrap_ipcp(int     argc,
                 cargs = 2;
                 if (matches(*argv, "type") == 0) {
                         ipcp_type = *(argv + 1);
-                } else if (matches(*argv, "dif") == 0) {
+                } else if (matches(*argv, "layer") == 0) {
                         dif_name = *(argv + 1);
                 } else if (matches(*argv, "name") == 0) {
                         name = *(argv + 1);
@@ -216,7 +216,7 @@ int do_bootstrap_ipcp(int     argc,
         }
 
         strcpy(conf.dif_info.dif_name, dif_name);
-        if (strcmp(ipcp_type, SHIM_UDP) != 0)
+        if (strcmp(ipcp_type, UDP) != 0)
                 conf.dif_info.dir_hash_algo = hash_algo;
 
         if (strcmp(ipcp_type, NORMAL) == 0) {
@@ -227,8 +227,8 @@ int do_bootstrap_ipcp(int     argc,
                 conf.addr_auth_type = addr_auth_type;
                 conf.routing_type = routing_type;
                 conf.pff_type = pff_type;
-        } else if (strcmp(ipcp_type, SHIM_UDP) == 0) {
-                conf.type = IPCP_SHIM_UDP;
+        } else if (strcmp(ipcp_type, UDP) == 0) {
+                conf.type = IPCP_UDP;
                 if (ip_addr == 0) {
                         usage();
                         return -1;
@@ -239,8 +239,8 @@ int do_bootstrap_ipcp(int     argc,
                 conf.type = IPCP_LOCAL;
         } else if (strcmp(ipcp_type, RAPTOR) == 0) {
                 conf.type = IPCP_RAPTOR;
-        } else if (strcmp(ipcp_type, SHIM_ETH_LLC) == 0) {
-                conf.type = IPCP_SHIM_ETH_LLC;
+        } else if (strcmp(ipcp_type, ETH_LLC) == 0) {
+                conf.type = IPCP_ETH_LLC;
                 if (if_name == NULL) {
                         usage();
                         return -1;
diff --git a/src/tools/irm/irm_ipcp_create.c b/src/tools/irm/irm_ipcp_create.c
index 1ec73049..fa453fee 100644
--- a/src/tools/irm/irm_ipcp_create.c
+++ b/src/tools/irm/irm_ipcp_create.c
@@ -44,11 +44,11 @@
 #include "irm_ops.h"
 #include "irm_utils.h"
 
-#define NORMAL       "normal"
-#define SHIM_UDP     "shim-udp"
-#define SHIM_ETH_LLC "shim-eth-llc"
-#define LOCAL        "local"
-#define RAPTOR       "raptor"
+#define NORMAL  "normal"
+#define UDP     "udp"
+#define ETH_LLC "eth-llc"
+#define LOCAL   "local"
+#define RAPTOR  "raptor"
 
 static void usage(void)
 {
@@ -56,7 +56,7 @@ static void usage(void)
                "                name <ipcp name>\n"
                "                type [TYPE]\n\n"
                "where TYPE = {" NORMAL " " LOCAL " "
-               SHIM_UDP " " SHIM_ETH_LLC " " RAPTOR "}\n");
+               UDP " " ETH_LLC " " RAPTOR "}\n");
 }
 
 int do_create_ipcp(int argc, char ** argv)
@@ -88,12 +88,12 @@ int do_create_ipcp(int argc, char ** argv)
 
         if (strcmp(ipcp_type, NORMAL) == 0)
                 type = IPCP_NORMAL;
-        else if (strcmp(ipcp_type, SHIM_UDP) == 0)
-                type = IPCP_SHIM_UDP;
+        else if (strcmp(ipcp_type, UDP) == 0)
+                type = IPCP_UDP;
         else if (strcmp(ipcp_type, LOCAL) == 0)
                 type = IPCP_LOCAL;
-        else if (strcmp(ipcp_type, SHIM_ETH_LLC) == 0)
-                type = IPCP_SHIM_ETH_LLC;
+        else if (strcmp(ipcp_type, ETH_LLC) == 0)
+                type = IPCP_ETH_LLC;
         else if (strcmp(ipcp_type, RAPTOR) == 0)
                 type = IPCP_RAPTOR;
         else {
diff --git a/src/tools/irm/irm_ipcp_enroll.c b/src/tools/irm/irm_ipcp_enroll.c
index 4beb6754..dc40567f 100644
--- a/src/tools/irm/irm_ipcp_enroll.c
+++ b/src/tools/irm/irm_ipcp_enroll.c
@@ -48,7 +48,7 @@ static void usage(void)
 {
         printf("Usage: irm ipcp enroll\n"
                "                name <ipcp name>\n"
-               "                dif <dif to enroll in>\n"
+               "                layer <layer to enroll in>\n"
                "                [autobind]\n");
 }
 
@@ -67,7 +67,7 @@ int do_enroll_ipcp(int argc, char ** argv)
                 cargs = 2;
                 if (matches(*argv, "name") == 0) {
                         name = *(argv + 1);
-                } else if (matches(*argv, "dif") == 0) {
+                } else if (matches(*argv, "layer") == 0) {
                         dif_name = *(argv + 1);
                 } else if (matches(*argv, "autobind") == 0) {
                         autobind = true;
diff --git a/src/tools/irm/irm_register.c b/src/tools/irm/irm_register.c
index 0a0fa5c0..34fd760a 100644
--- a/src/tools/irm/irm_register.c
+++ b/src/tools/irm/irm_register.c
@@ -43,32 +43,32 @@
 #include "irm_ops.h"
 #include "irm_utils.h"
 
-#define MAX_DIFS 128
+#define MAX_LAYERS 128
 
 static void usage(void)
 {
         printf("Usage: irm register\n"
                "           name <name>\n"
-               "           dif <dif name to register with>\n"
-               "           [dif <dif name to register with>]\n"
-               "           [... (maximum %d difs)]\n"
-               , MAX_DIFS);
+               "           layer <layer to register with>\n"
+               "           [layer <layer to register with>]\n"
+               "           [... (maximum %d layers)]\n"
+               , MAX_LAYERS);
 }
 
 
 int do_register(int argc, char ** argv)
 {
         char * name = NULL;
-        char * difs[MAX_DIFS];
+        char * difs[MAX_LAYERS];
         size_t difs_len = 0;
 
         while (argc > 0) {
                 if (matches(*argv, "name") == 0) {
                         name = *(argv + 1);
-                } else if (matches(*argv, "dif") == 0) {
+                } else if (matches(*argv, "layer") == 0) {
                         difs[difs_len++] = *(argv + 1);
-                        if (difs_len > MAX_DIFS) {
-                                printf("Too many difs specified\n");
+                        if (difs_len > MAX_LAYERS) {
+                                printf("Too many layers specified\n");
                                 return -1;
                         }
                 } else {
diff --git a/src/tools/irm/irm_unregister.c b/src/tools/irm/irm_unregister.c
index 09b7ec21..64053706 100644
--- a/src/tools/irm/irm_unregister.c
+++ b/src/tools/irm/irm_unregister.c
@@ -44,30 +44,30 @@
 #include "irm_ops.h"
 #include "irm_utils.h"
 
-#define MAX_DIFS 128
+#define MAX_LAYERS 128
 
 static void usage(void)
 {
         printf("Usage: irm unregister\n"
                "           name <name>\n"
-               "           dif <dif name to unregister from>\n"
-               "           [dif <dif name to unregister from>]\n"
-               "           [... (maximum %d difs)]\n"
-               , MAX_DIFS);
+               "           layer <layer to unregister from>\n"
+               "           [layer <layer to unregister from>]\n"
+               "           [... (maximum %d layers)]\n"
+               , MAX_LAYERS);
 }
 
 int do_unregister(int argc, char ** argv)
 {
-        char * difs[MAX_DIFS];
+        char * difs[MAX_LAYERS];
         size_t difs_len = 0;
         char * name = NULL;
 
         while (argc > 0) {
                 if (matches(*argv, "name") == 0) {
                         name = *(argv + 1);
-                } else if (matches(*argv, "dif") == 0) {
+                } else if (matches(*argv, "layer") == 0) {
                         difs[difs_len++] = *(argv + 1);
-                        if (difs_len > MAX_DIFS) {
+                        if (difs_len > MAX_LAYERS) {
                                 printf("Too many difs specified\n");
                                 return -1;
                         }