Merged in sandervrijders/ouroboros/be-shm-pci (pull request #247)

ipcpd: normal: Add operations to get and set the PCI

10 files changed, 318 insertions, 127 deletions

diff --git a/src/ipcpd/normal/CMakeLists.txt b/src/ipcpd/normal/CMakeLists.txt
index 68dca4b3..654bb127 100644
--- a/src/ipcpd/normal/CMakeLists.txt
+++ b/src/ipcpd/normal/CMakeLists.txt
@@ -22,12 +22,14 @@ protobuf_generate_c(FLOW_ALLOC_SRCS FLOW_ALLOC_HDRS
 
 set(SOURCE_FILES
         # Add source files here
-        main.c
+        cdap_request.c
+        crc32.c
         fmgr.c
         frct.c
-        cdap_request.c
+        main.c
         ribmgr.c
         rmt.c
+        shm_pci.c
 )
 
 add_executable (ipcpd-normal ${SOURCE_FILES} ${IPCP_SOURCES}
diff --git a/src/ipcpd/normal/crc32.c b/src/ipcpd/normal/crc32.c
new file mode 100644
index 00000000..ad3e2b35
--- /dev/null
+++ b/src/ipcpd/normal/crc32.c
@@ -0,0 +1,83 @@
+/*
+ * Ouroboros - Copyright (C) 2016
+ *
+ * 32-bit Cyclic Redundancy Check
+ *
+ *    Sander Vrijders   <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#include <stddef.h>
+
+#include "crc32.h"
+
+static const uint32_t crc32_table[256] = {
+  0x00000000, 0x77073096, 0xee0e612c, 0x990951ba, 0x076dc419, 0x706af48f,
+  0xe963a535, 0x9e6495a3, 0x0edb8832, 0x79dcb8a4, 0xe0d5e91e, 0x97d2d988,
+  0x09b64c2b, 0x7eb17cbd, 0xe7b82d07, 0x90bf1d91, 0x1db71064, 0x6ab020f2,
+  0xf3b97148, 0x84be41de, 0x1adad47d, 0x6ddde4eb, 0xf4d4b551, 0x83d385c7,
+  0x136c9856, 0x646ba8c0, 0xfd62f97a, 0x8a65c9ec, 0x14015c4f, 0x63066cd9,
+  0xfa0f3d63, 0x8d080df5, 0x3b6e20c8, 0x4c69105e, 0xd56041e4, 0xa2677172,
+  0x3c03e4d1, 0x4b04d447, 0xd20d85fd, 0xa50ab56b, 0x35b5a8fa, 0x42b2986c,
+  0xdbbbc9d6, 0xacbcf940, 0x32d86ce3, 0x45df5c75, 0xdcd60dcf, 0xabd13d59,
+  0x26d930ac, 0x51de003a, 0xc8d75180, 0xbfd06116, 0x21b4f4b5, 0x56b3c423,
+  0xcfba9599, 0xb8bda50f, 0x2802b89e, 0x5f058808, 0xc60cd9b2, 0xb10be924,
+  0x2f6f7c87, 0x58684c11, 0xc1611dab, 0xb6662d3d, 0x76dc4190, 0x01db7106,
+  0x98d220bc, 0xefd5102a, 0x71b18589, 0x06b6b51f, 0x9fbfe4a5, 0xe8b8d433,
+  0x7807c9a2, 0x0f00f934, 0x9609a88e, 0xe10e9818, 0x7f6a0dbb, 0x086d3d2d,
+  0x91646c97, 0xe6635c01, 0x6b6b51f4, 0x1c6c6162, 0x856530d8, 0xf262004e,
+  0x6c0695ed, 0x1b01a57b, 0x8208f4c1, 0xf50fc457, 0x65b0d9c6, 0x12b7e950,
+  0x8bbeb8ea, 0xfcb9887c, 0x62dd1ddf, 0x15da2d49, 0x8cd37cf3, 0xfbd44c65,
+  0x4db26158, 0x3ab551ce, 0xa3bc0074, 0xd4bb30e2, 0x4adfa541, 0x3dd895d7,
+  0xa4d1c46d, 0xd3d6f4fb, 0x4369e96a, 0x346ed9fc, 0xad678846, 0xda60b8d0,
+  0x44042d73, 0x33031de5, 0xaa0a4c5f, 0xdd0d7cc9, 0x5005713c, 0x270241aa,
+  0xbe0b1010, 0xc90c2086, 0x5768b525, 0x206f85b3, 0xb966d409, 0xce61e49f,
+  0x5edef90e, 0x29d9c998, 0xb0d09822, 0xc7d7a8b4, 0x59b33d17, 0x2eb40d81,
+  0xb7bd5c3b, 0xc0ba6cad, 0xedb88320, 0x9abfb3b6, 0x03b6e20c, 0x74b1d29a,
+  0xead54739, 0x9dd277af, 0x04db2615, 0x73dc1683, 0xe3630b12, 0x94643b84,
+  0x0d6d6a3e, 0x7a6a5aa8, 0xe40ecf0b, 0x9309ff9d, 0x0a00ae27, 0x7d079eb1,
+  0xf00f9344, 0x8708a3d2, 0x1e01f268, 0x6906c2fe, 0xf762575d, 0x806567cb,
+  0x196c3671, 0x6e6b06e7, 0xfed41b76, 0x89d32be0, 0x10da7a5a, 0x67dd4acc,
+  0xf9b9df6f, 0x8ebeeff9, 0x17b7be43, 0x60b08ed5, 0xd6d6a3e8, 0xa1d1937e,
+  0x38d8c2c4, 0x4fdff252, 0xd1bb67f1, 0xa6bc5767, 0x3fb506dd, 0x48b2364b,
+  0xd80d2bda, 0xaf0a1b4c, 0x36034af6, 0x41047a60, 0xdf60efc3, 0xa867df55,
+  0x316e8eef, 0x4669be79, 0xcb61b38c, 0xbc66831a, 0x256fd2a0, 0x5268e236,
+  0xcc0c7795, 0xbb0b4703, 0x220216b9, 0x5505262f, 0xc5ba3bbe, 0xb2bd0b28,
+  0x2bb45a92, 0x5cb36a04, 0xc2d7ffa7, 0xb5d0cf31, 0x2cd99e8b, 0x5bdeae1d,
+  0x9b64c2b0, 0xec63f226, 0x756aa39c, 0x026d930a, 0x9c0906a9, 0xeb0e363f,
+  0x72076785, 0x05005713, 0x95bf4a82, 0xe2b87a14, 0x7bb12bae, 0x0cb61b38,
+  0x92d28e9b, 0xe5d5be0d, 0x7cdcefb7, 0x0bdbdf21, 0x86d3d2d4, 0xf1d4e242,
+  0x68ddb3f8, 0x1fda836e, 0x81be16cd, 0xf6b9265b, 0x6fb077e1, 0x18b74777,
+  0x88085ae6, 0xff0f6a70, 0x66063bca, 0x11010b5c, 0x8f659eff, 0xf862ae69,
+  0x616bffd3, 0x166ccf45, 0xa00ae278, 0xd70dd2ee, 0x4e048354, 0x3903b3c2,
+  0xa7672661, 0xd06016f7, 0x4969474d, 0x3e6e77db, 0xaed16a4a, 0xd9d65adc,
+  0x40df0b66, 0x37d83bf0, 0xa9bcae53, 0xdebb9ec5, 0x47b2cf7f, 0x30b5ffe9,
+  0xbdbdf21c, 0xcabac28a, 0x53b39330, 0x24b4a3a6, 0xbad03605, 0xcdd70693,
+  0x54de5729, 0x23d967bf, 0xb3667a2e, 0xc4614ab8, 0x5d681b02, 0x2a6f2b94,
+  0xb40bbe37, 0xc30c8ea1, 0x5a05df1b, 0x2d02ef8d
+};
+
+void crc32(uint32_t * crc, const uint8_t * buf, size_t len)
+{
+  size_t n;
+
+  *crc = *crc ^ 0xffffffff;
+
+  for (n = 0; n < len; n++)
+    *crc = crc32_table[(*crc ^ buf[n]) & 0xff] ^ (*crc >> 8);
+
+  *crc = *crc ^ 0xffffffff;
+}
diff --git a/src/ipcpd/normal/crc32.h b/src/ipcpd/normal/crc32.h
new file mode 100644
index 00000000..f22bbc19
--- /dev/null
+++ b/src/ipcpd/normal/crc32.h
@@ -0,0 +1,30 @@
+/*
+ * Ouroboros - Copyright (C) 2016
+ *
+ * 32-bit Cyclic Redundancy Check
+ *
+ *    Sander Vrijders   <[email protected]>
+ *
+ * This program is free software; you can redistribute it and/or modify
+ * it under the terms of the GNU General Public License as published by
+ * the Free Software Foundation; either version 2 of the License, or
+ * (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software
+ * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ */
+
+#ifndef OUROBOROS_IPCP_CRC32_H
+#define OUROBOROS_IPCP_CRC32_H
+
+#include <stdint.h>
+
+void crc32(uint32_t * crc, const uint8_t * buf, size_t len);
+
+#endif /* OUROBOROS_IPCP_CRC32_H */
diff --git a/src/ipcpd/normal/dt_const.h b/src/ipcpd/normal/dt_const.h
index b33f16c5..eda66838 100644
--- a/src/ipcpd/normal/dt_const.h
+++ b/src/ipcpd/normal/dt_const.h
@@ -25,14 +25,15 @@
 #define IPCP_DT_CONST_H
 
 #include <stdint.h>
+#include <stdbool.h>
 
 struct dt_const {
-        uint8_t addr_size;
-        uint8_t cep_id_size;
-        uint8_t pdu_length_size;
-        uint8_t seqno_size;
-        uint8_t ttl_size;
-        uint8_t chk_size;
+        uint8_t  addr_size;
+        uint8_t  cep_id_size;
+        uint8_t  pdu_length_size;
+        uint8_t  seqno_size;
+        bool     has_ttl;
+        bool     has_chk;
         uint32_t min_pdu_size;
         uint32_t max_pdu_size;
 };
diff --git a/src/ipcpd/normal/frct.c b/src/ipcpd/normal/frct.c
index 7c2eba61..417815b7 100644
--- a/src/ipcpd/normal/frct.c
+++ b/src/ipcpd/normal/frct.c
@@ -126,6 +126,14 @@ int frct_fini()
         return 0;
 }
 
+struct dt_const * frct_dt_const()
+{
+        if (frct == NULL)
+                return NULL;
+
+        return frct->dtc;
+}
+
 int frct_dt_flow(int fd,
                  enum qos_cube qos)
 {
diff --git a/src/ipcpd/normal/frct.h b/src/ipcpd/normal/frct.h
index 91b2dfc7..09873445 100644
--- a/src/ipcpd/normal/frct.h
+++ b/src/ipcpd/normal/frct.h
@@ -30,26 +30,29 @@
 
 struct frct_i;
 
-int             frct_init(struct dt_const * dtc,
-                          uint32_t address);
-int             frct_fini();
+int               frct_init(struct dt_const * dtc,
+                            uint32_t address);
+int               frct_fini();
+
+struct dt_const * frct_dt_const();
+
+int               frct_dt_flow(int fd,
+                               enum qos_cube qos);
 
-int             frct_dt_flow(int fd,
-                             enum qos_cube qos);
 /*
  * FIXME: Will take the index in the DU map,
  * possibly cep-ids and address
  */
-int             frct_rmt_post();
+int                frct_rmt_post();
 
-struct frct_i * frct_i_create(uint32_t      address,
-                              buffer_t *    buf,
-                              enum qos_cube cube);
+struct frct_i *    frct_i_create(uint32_t      address,
+                                 buffer_t *    buf,
+                                 enum qos_cube cube);
 /* FIXME: Hand QoS cube here too? We received it in the flow alloc message. */
-int             frct_i_accept(struct frct_i * instance,
-                              buffer_t *      buf);
-int             frct_i_destroy(struct frct_i * instance,
-                               buffer_t *      buf);
+int                frct_i_accept(struct frct_i * instance,
+                                 buffer_t *      buf);
+int                frct_i_destroy(struct frct_i * instance,
+                                  buffer_t *      buf);
 
 /* FIXME: Add read/write ops for frct instances */
 
diff --git a/src/ipcpd/normal/ribmgr.c b/src/ipcpd/normal/ribmgr.c
index 007361fd..9733abc9 100644
--- a/src/ipcpd/normal/ribmgr.c
+++ b/src/ipcpd/normal/ribmgr.c
@@ -241,8 +241,8 @@ int ribmgr_cdap_write(struct cdap * instance,
                 rib->dtc.cep_id_size = msg->cep_id_size;
                 rib->dtc.pdu_length_size = msg->pdu_length_size;
                 rib->dtc.seqno_size = msg->seqno_size;
-                rib->dtc.ttl_size = msg->ttl_size;
-                rib->dtc.chk_size = msg->chk_size;
+                rib->dtc.has_ttl = msg->has_ttl;
+                rib->dtc.has_chk = msg->has_chk;
                 rib->dtc.min_pdu_size = msg->min_pdu_size;
                 rib->dtc.max_pdu_size = msg->max_pdu_size;
 
@@ -318,8 +318,8 @@ int ribmgr_cdap_start(struct cdap * instance,
                 stat_info.cep_id_size = rib->dtc.cep_id_size;
                 stat_info.pdu_length_size = rib->dtc.pdu_length_size;
                 stat_info.seqno_size = rib->dtc.seqno_size;
-                stat_info.ttl_size = rib->dtc.ttl_size;
-                stat_info.chk_size = rib->dtc.chk_size;
+                stat_info.has_ttl = rib->dtc.has_ttl;
+                stat_info.has_chk = rib->dtc.has_chk;
                 stat_info.min_pdu_size  = rib->dtc.min_pdu_size;
                 stat_info.max_pdu_size = rib->dtc.max_pdu_size;
 
@@ -529,8 +529,8 @@ int ribmgr_bootstrap(struct dif_config * conf)
         rib->dtc.cep_id_size  = conf->cep_id_size;
         rib->dtc.pdu_length_size = conf->pdu_length_size;
         rib->dtc.seqno_size = conf->seqno_size;
-        rib->dtc.ttl_size = conf->ttl_size;
-        rib->dtc.chk_size = conf->chk_size;
+        rib->dtc.has_ttl = conf->has_ttl;
+        rib->dtc.has_chk = conf->has_chk;
         rib->dtc.min_pdu_size = conf->min_pdu_size;
         rib->dtc.max_pdu_size = conf->max_pdu_size;
 
diff --git a/src/ipcpd/normal/shm_pci.c b/src/ipcpd/normal/shm_pci.c
index 144bd15e..94629790 100644
--- a/src/ipcpd/normal/shm_pci.c
+++ b/src/ipcpd/normal/shm_pci.c
@@ -21,127 +21,183 @@
  * Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
  */
 
-#include <ourboros/errno.h>
-
-#include "shm_pci.h"
-#include <stdlib.h>
-
-#define SHM_PCI_HEAD_SIZE(a, b) a.addr_size * 2 +  \
-        a.cep_id_size * 2 +                    \
-        a.pdu_length_size +                    \
-        b.ttl_size +                           \
-        a.seqno_size +                         \
-        a.qos_id_size
-#define SHM_PCI_TAIL_SIZE(b) b.chk_size
-
 #define OUROBOROS_PREFIX "ipcpd/shm_pci"
 
 #include <ouroboros/logs.h>
+#include <ouroboros/errno.h>
 
-struct shm_pci {
-        /* head */
-        uint8_t * dst_addr;
-        uint8_t * src_addr;
-        uint8_t * dst_cep_id;
-        uint8_t * src_cep_id;
-        uint8_t * pdu_length;
-        uint8_t * ttl;
-        uint8_t * seqno;
-        uint8_t * qos_id;
+#include <stdlib.h>
+#include <string.h>
 
-        uint8_t * chk;
+#include "shm_pci.h"
+#include "frct.h"
+#include "crc32.h"
 
-        struct shm_du_buff * dub;
+#define QOS_ID_SIZE 1
+#define DEFAULT_TTL 60
+#define TTL_SIZE 1
+#define CHK_SIZE 4
 
-        struct ipcp_dtp_const dtpc;
-        struct ipcp_dup_const dupc;
+static int shm_pci_head_size(struct dt_const * dtc)
+{
+        int len = 0;
 
-};
+        len = dtc->addr_size * 2 + dtc->cep_id_size * 2
+                + dtc->pdu_length_size + dtc->seqno_size
+                + QOS_ID_SIZE;
 
-shm_pci_t * shm_pci_create(struct shm_du_buff      * dub,
-                           const struct ipcp_dtp_const * dtpc,
-                           const struct ipcp_dup_const * dupc)
+        if (dtc->has_ttl)
+                len += TTL_SIZE;
+
+        return len;
+}
+
+static int shm_pci_tail_size(struct dt_const * dtc)
 {
-        struct shm_pci * p;
+        return dtc->has_chk ? CHK_SIZE : 0;
+}
 
-        if (dub == NULL) {
-                LOG_DBGF("Bogus input. Bugging out.");
-                return NULL;
+int shm_pci_ser(struct shm_du_buff * sdb,
+                struct pci * pci)
+{
+        uint8_t * head;
+        uint8_t * tail;
+        int offset = 0;
+        struct dt_const * dtc;
+        uint8_t ttl = DEFAULT_TTL;
+
+        dtc = frct_dt_const();
+        if (dtc == NULL)
+                return -1;
+
+        head = shm_du_buff_head_alloc(sdb, shm_pci_head_size(dtc));
+        if (head == NULL)
+                return -1;
+
+        memcpy(head, &pci->dst_addr, dtc->addr_size);
+        offset += dtc->addr_size;
+        memcpy(head + offset, &pci->src_addr, dtc->addr_size);
+        offset += dtc->addr_size;
+        memcpy(head + offset, &pci->dst_cep_id, dtc->cep_id_size);
+        offset += dtc->cep_id_size;
+        memcpy(head + offset, &pci->src_cep_id, dtc->cep_id_size);
+        offset += dtc->cep_id_size;
+        memcpy(head + offset, &pci->pdu_length, dtc->pdu_length_size);
+        offset += dtc->pdu_length_size;
+        memcpy(head + offset, &pci->seqno, dtc->seqno_size);
+        offset += dtc->seqno_size;
+        memcpy(head + offset, &pci->qos_id, QOS_ID_SIZE);
+        offset += QOS_ID_SIZE;
+        if (dtc->has_ttl)
+                memcpy(head + offset, &ttl, TTL_SIZE);
+
+        if (dtc->has_chk) {
+                tail = shm_du_buff_tail_alloc(sdb, shm_pci_tail_size(dtc));
+                if (tail == NULL) {
+                        shm_du_buff_head_release(sdb, shm_pci_tail_size(dtc));
+                        return -1;
+                }
+
+                crc32((uint32_t *) tail, head, tail - head);
         }
 
-        p = malloc(sizeof *p);
+        return 0;
+}
 
-        if (p == NULL)
-                return NULL;
+struct pci * shm_pci_des(struct shm_du_buff * sdb)
+{
+        uint8_t * head;
+        struct pci * pci;
+        int offset = 0;
+        struct dt_const * dtc;
 
-        p->dub = dub;
+        head = shm_du_buff_head(sdb);
+        if (head == NULL)
+                return NULL;
 
-        p->dtpc = *dtpc;
-        p->dupc = *dupc;
+        dtc = frct_dt_const();
+        if (dtc == NULL)
+                return NULL;
 
-        p->dst_addr   = NULL;
-        p->src_addr   = NULL;
-        p->dst_cep_id = NULL;
-        p->src_cep_id = NULL;
-        p->pdu_length = NULL;
-        p->ttl        = NULL;
-        p->seqno      = NULL;
-        p->qos_id     = NULL;
-        p->chk        = NULL;
+        pci = malloc(sizeof(*pci));
+        if (pci == NULL)
+                return NULL;
 
-        return p;
+        memcpy(&pci->dst_addr, head, dtc->addr_size);
+        offset += dtc->addr_size;
+        memcpy(&pci->src_addr, head + offset, dtc->addr_size);
+        offset += dtc->addr_size;
+        memcpy(&pci->dst_cep_id, head + offset, dtc->cep_id_size);
+        offset += dtc->cep_id_size;
+        memcpy(&pci->src_cep_id, head + offset, dtc->cep_id_size);
+        offset += dtc->cep_id_size;
+        memcpy(&pci->pdu_length, head + offset, dtc->pdu_length_size);
+        offset += dtc->pdu_length_size;
+        memcpy(&pci->seqno, head + offset, dtc->seqno_size);
+        offset += dtc->seqno_size;
+        memcpy(&pci->qos_id, head + offset, QOS_ID_SIZE);
+        offset += QOS_ID_SIZE;
+        if (dtc->has_ttl)
+                memcpy(&pci->ttl, head + offset, TTL_SIZE);
+
+        return pci;
 }
 
-void shm_pci_destroy(shm_pci_t * pci)
+int shm_pci_shrink(struct shm_du_buff * sdb)
 {
-        free(pci);
-}
+        struct dt_const * dtc;
 
-int shm_pci_init(shm_pci_t * pci)
-{
-        if (pci == NULL) {
-                LOG_DBGF("Bogus input. Bugging out.");
-                return -EINVAL;
-        }
+        if (sdb == NULL)
+                return -1;
 
-        uint8_t * pci_head = shm_du_buff_head_alloc(
-                pci->dub, SHM_PCI_HEAD_SIZE(pci->dtpc, pci->dupc));
-        uint8_t * pci_tail = shm_du_buff_tail_alloc(
-                pci->dub, SHM_PCI_TAIL_SIZE(pci->dupc));
+        dtc = frct_dt_const();
+        if (dtc == NULL)
+                return -1;
 
-        if (pci_head == NULL) {
-                LOG_DBG("Failed to allocate space for PCI at head.");
-                return -ENOBUFS;
+        if (shm_du_buff_head_release(sdb, shm_pci_head_size(dtc))) {
+                LOG_ERR("Failed to shrink head.");
+                return -1;
         }
 
-        if (pci_tail == NULL) {
-                LOG_DBG("Failed to allocate space for PCI at tail.");
-                return -ENOBUFS;
+        if (shm_du_buff_tail_release(sdb, shm_pci_tail_size(dtc))) {
+                LOG_ERR("Failed to shrink tail.");
+                return -1;
         }
 
-        pci->dst_addr   = pci_head;
-        pci->src_addr   = (pci_head += pci->dtpc.addr_size);
-        pci->dst_cep_id = (pci_head += pci->dtpc.addr_size);
-        pci->src_cep_id = (pci_head += pci->dtpc.cep_id_size);
-        pci->pdu_length = (pci_head += pci->dtpc.cep_id_size);
-        pci->ttl        = (pci_head += pci->dtpc.pdu_length_size);
-        pci->seqno      = (pci_head += pci->dupc.ttl_size);
-        pci->qos_id     = (pci_head += pci->dtpc.seqno_size);
-
-        pci->chk        = (pci_tail);
-
         return 0;
 }
 
-void shm_pci_release(shm_pci_t * pci)
+int shm_pci_dec_ttl(struct shm_du_buff * sdb)
 {
-        if (pci == NULL)
-                return;
+        struct dt_const * dtc;
+        int offset = 0;
+        uint8_t * head;
+        uint8_t * tail;
 
-        if (pci->dub == NULL)
-                return;
+        dtc = frct_dt_const();
+        if (dtc == NULL)
+                return -1;
 
-        shm_du_buff_head_release(pci->dub, SHM_PCI_HEAD_SIZE(pci->dtpc,
-                                                             pci->dupc));
-        shm_du_buff_tail_release(pci->dub, SHM_PCI_TAIL_SIZE(pci->dupc));
+        if (dtc->has_ttl == false)
+                return 0;
+
+        offset = shm_pci_head_size(dtc) - 1;
+
+        head = shm_du_buff_head(sdb);
+        if (head == NULL)
+                return -1;
+
+        head[offset]--;
+
+        if (dtc->has_chk) {
+                tail = shm_du_buff_tail(sdb);
+                if (tail == NULL)
+                        return -1;
+
+                tail -= CHK_SIZE;
+
+                crc32((uint32_t *) tail, head, tail - head);
+        }
+
+        return 0;
 }
diff --git a/src/ipcpd/normal/shm_pci.h b/src/ipcpd/normal/shm_pci.h
index cb8dd5dd..aa9770b4 100644
--- a/src/ipcpd/normal/shm_pci.h
+++ b/src/ipcpd/normal/shm_pci.h
@@ -24,20 +24,28 @@
 #ifndef OUROBOROS_IPCP_SHM_PCI_H
 #define OUROBOROS_IPCP_SHM_PCI_H
 
-#include <ouroboros/shm_du_map.h>
+#include <ouroboros/shm_rdrbuff.h>
 
 #include <dt_const.h>
 
-struct shm_pci;
+struct pci {
+        uint64_t dst_addr;
+        uint64_t src_addr;
+        uint32_t dst_cep_id;
+        uint32_t src_cep_id;
+        uint32_t pdu_length;
+        uint64_t seqno;
+        uint8_t  qos_id;
+        uint8_t  ttl;
+};
 
-typedef struct shm_pci shm_pci_t;
+int          shm_pci_ser(struct shm_du_buff * sdb,
+                         struct pci * pci);
 
-shm_pci_t * shm_pci_create(struct shm_du_buff          * dub,
-                           const struct ipcp_dtp_const * dtpc,
-                           const struct ipcp_dup_const * dupc);
-void    shm_pci_destroy(shm_pci_t * pci);
+struct pci * shm_pci_des(struct shm_du_buff * sdb);
 
-int     shm_pci_init(shm_pci_t * pci);
-void    shm_pci_release(shm_pci_t * pci);
+int          shm_pci_shrink(struct shm_du_buff * sdb);
+
+int          shm_pci_dec_ttl(struct shm_du_buff * sdb);
 
 #endif /* OUROBOROS_IPCP_SHM_PCI_H */
diff --git a/src/ipcpd/normal/static_info.proto b/src/ipcpd/normal/static_info.proto
index 24b7994a..04824a38 100644
--- a/src/ipcpd/normal/static_info.proto
+++ b/src/ipcpd/normal/static_info.proto
@@ -3,8 +3,8 @@ message static_info_msg {
         required uint32 cep_id_size     = 2;
         required uint32 pdu_length_size = 3;
         required uint32 seqno_size      = 4;
-        required uint32 ttl_size        = 5;
-        required uint32 chk_size        = 6;
+        required bool   has_ttl         = 5;
+        required bool   has_chk         = 6;
         required uint32 min_pdu_size    = 7;
         required uint32 max_pdu_size    = 8;
         required uint32 address         = 9;