add: backplane NIC info implementation

Author: patrislav1

.gitignore

@@ -1,4 +1,5 @@
 /.vscode
+/.cache
 /build
 *.bkp
 /doc/*.ods#

CMakeLists.txt

@@ -5,6 +5,10 @@ project(mmc-mailbox VERSION 1.0.2)
 include(GNUInstallDirs)
 include(CMakePackageConfigHelpers)
 
+set(CMAKE_C_STANDARD 11)
+set(CMAKE_C_STANDARD_REQUIRED TRUE)
+set(CMAKE_EXPORT_COMPILE_COMMANDS ON)
+
 # mmcmb library
 
 add_library(mmcmb SHARED mmcmb.c)

mmcctrld.c

@@ -11,17 +11,23 @@
  ***************************************************************************/
 
 #include <errno.h>
+#include <net/if.h>
+#include <netinet/in.h>
 #include <signal.h>
 #include <stdbool.h>
 #include <stdio.h>
 #include <stdlib.h>
 #include <string.h>
+#include <sys/ioctl.h>
+#include <sys/socket.h>
 #include <sys/stat.h>
 #include <sys/types.h>
 #include <syslog.h>
 #include <time.h>
 #include <unistd.h>
+#include <ifaddrs.h>
 
+#include "mmcmb/fpga_mailbox_layout.h"
 #include "mmcmb/mmcmb.h"
 
 // Poll FPGA control register 4 times per second.
@@ -93,6 +99,48 @@ void handle_fpga_ctrl(const mb_fpga_ctrl_t* ctrl)
     terminate = true;
 }
 
+mb_nic_information_t get_nic_info(const char* ifname)
+{
+    mb_nic_information_t result = {0};
+
+    // Get MAC address via ioctl
+    int fd = socket(AF_INET, SOCK_DGRAM, 0);
+    if (fd > 0) {
+        struct ifreq ifr;
+        ifr.ifr_addr.sa_family = AF_INET;
+        strncpy(ifr.ifr_name, ifname, IFNAMSIZ - 1);
+        if (ioctl(fd, SIOCGIFHWADDR, &ifr) == 0) {
+            const uint8_t* mac_addr = (const uint8_t*)&ifr.ifr_ifru.ifru_hwaddr.sa_data[0];
+            memcpy(result.mac_addr, mac_addr, sizeof(result.mac_addr));
+        } else {
+            syslog(LOG_ERR, "Could not get MAC address of %s: %s", ifname, strerror(errno));
+        }
+        close(fd);
+    }
+
+    // Get primary IPv4 & IPv6 addresses via getifaddrs()
+    struct ifaddrs *ifap, *ifa;
+    getifaddrs(&ifap);
+    for (ifa = ifap; ifa; ifa = ifa->ifa_next) {
+        if (ifa->ifa_addr && !strcmp(ifa->ifa_name, ifname)) {
+            switch (ifa->ifa_addr->sa_family) {
+                case AF_INET: {
+                    const struct sockaddr_in* sa = (struct sockaddr_in*)ifa->ifa_addr;
+                    memcpy(result.ipv4_addr, &sa->sin_addr, sizeof(result.ipv4_addr));
+                } break;
+                case AF_INET6: {
+                    const struct sockaddr_in6* sa = (struct sockaddr_in6*)ifa->ifa_addr;
+                    memcpy(result.ipv6_addr, sa->sin6_addr.s6_addr, sizeof(result.ipv6_addr));
+                } break;
+                default:
+                    break;
+            }
+        }
+    }
+
+    return result;
+}
+
 int main()
 {
     if (geteuid() != 0) {
@@ -122,6 +170,11 @@ int main()
         goto finish;
     }
 
+    const char* bp_eth_ifname = getenv("BP_ETH_IFNAME");
+    if (!bp_eth_ifname) {
+        bp_eth_ifname = "eth0";
+    }
+
     const struct timespec ts_poll = {
         .tv_nsec = POLL_INTERVAL_MS * 1e6,
     };
@@ -135,6 +188,10 @@ int main()
             break;
         }
         handle_fpga_ctrl(&ctrl);
+
+        mb_nic_information_t nic_info = get_nic_info(bp_eth_ifname);
+        mb_set_bp_eth_info(&nic_info);
+
         nanosleep(&ts_poll, NULL);
     }
 

mmcmb.c

@@ -10,6 +10,8 @@
  *                                                                         *
  ***************************************************************************/
 
+#include "mmcmb/mmcmb.h"
+
 #include <dirent.h>
 #include <errno.h>
 #include <fcntl.h>
@@ -207,3 +209,8 @@ bool mb_set_fpga_status(const mb_fpga_status_t* stat)
 {
     return mb_write_at(MB_EEPROM_OFFS(fpga_status), stat, sizeof(*stat));
 }
+
+bool mb_set_bp_eth_info(const mb_nic_information_t* nic_info)
+{
+    return mb_write_at(MB_EEPROM_OFFS(bp_eth_info), nic_info, sizeof(*nic_info));
+}

mmcmb/fpga_mailbox_layout.h

@@ -14,6 +14,7 @@
 
 #include <assert.h>
 #include <stdint.h>
+#include <stddef.h>
 
 #define MB_PACKED __attribute__((packed)) __attribute__((scalar_storage_order("little-endian")))
 
@@ -112,7 +113,7 @@ typedef struct mb_memory_contents {
     mb_mmc_information_t mmc_information;
     mb_mmc_sensor_t mmc_sensor[40];
     uint8_t reserved[43];
-    mb_nic_information_t bp_eth_information;
+    mb_nic_information_t bp_eth_info;
     mb_fpga_ctrl_t fpga_ctrl;
     mb_fpga_status_t fpga_status;
 } MB_PACKED mb_memory_contents_t;
@@ -147,6 +148,6 @@ static_assert(MB_EEPROM_OFFS(application_data) == 1032, "Offset of application_d
 static_assert(MB_EEPROM_OFFS(mmc_information) == 1288, "Offset of mmc_information incorrect");
 static_assert(MB_EEPROM_OFFS(mmc_sensor) == 1336, "Offset of mmc_sensor incorrect");
 static_assert(MB_EEPROM_OFFS(reserved) == 1976, "Offset of reserved incorrect");
-static_assert(MB_EEPROM_OFFS(bp_eth_information) == 2019, "Offset of NIC information incorrect");
+static_assert(MB_EEPROM_OFFS(bp_eth_info) == 2019, "Offset of NIC information incorrect");
 static_assert(MB_EEPROM_OFFS(fpga_ctrl) == 2045, "Offset of fpga_ctrl incorrect");
 static_assert(MB_EEPROM_OFFS(fpga_status) == 2046, "Offset of fpga_status incorrect");

mmcmb/mmcmb.h

@@ -16,6 +16,7 @@
 extern "C" {
 #endif
 
+#include <stdbool.h>
 #include <stddef.h>
 
 #include "fpga_mailbox_layout.h"
@@ -46,6 +47,9 @@ bool mb_get_fpga_ctrl(mb_fpga_ctrl_t* ctrl);
 // Set FPGA status
 bool mb_set_fpga_status(const mb_fpga_status_t* stat);
 
+// Set Backplane NIC addresses
+bool mb_set_bp_eth_info(const mb_nic_information_t* nic_info);
+
 // Get mmc-mailbox "EEPROM" device path, returns NULL on error
 const char* mb_get_eeprom_path(void);