From 25b9655f60d192f7f3c8352c07284a679c68e25c Mon Sep 17 00:00:00 2001
From: Brendan Chandler <bchandler@anl.gov>
Date: Tue, 16 Feb 2021 12:51:11 -0600
Subject: [PATCH] RTEMS DHCP: Use safer versions of string functions

Use strtok_r rather than strtok

Use strlen() rather than harcoded string size.  GCC should optimize
this to the hardcoded string size, so the result should be the same
but maybe prevents future mistakes.

replace strncpy() with snprintf() to avoid issues with NULL terminated
strings.
---
 modules/libcom/RTEMS/posix/rtems_init.c | 27 ++++++++++++++++---------
 1 file changed, 18 insertions(+), 9 deletions(-)

diff --git a/modules/libcom/RTEMS/posix/rtems_init.c b/modules/libcom/RTEMS/posix/rtems_init.c
index 10795a66e..bd31e6033 100644
--- a/modules/libcom/RTEMS/posix/rtems_init.c
+++ b/modules/libcom/RTEMS/posix/rtems_init.c
@@ -715,43 +715,52 @@ dhcpcd_hook_handler(rtems_dhcpcd_hook *hook, char *const *env)
     sprintf(ifnamebuf, "%s", getPrimaryNetworkInterface());
 
     while (*env != NULL) {
+        char const * interface = "interface";
+        char const * reason = "reason";
+        char const * bound_str = "BOUND";
+        
         name = strtok_r(*env,"=", &env_position);
         value = strtok_r(NULL,"=", &env_position);
         printf("all out ---> %s = %s\n", name, value);
 
-        if (!strcmp(name, "interface") &&
+        if (!strncmp(name, interface, strlen(interface)) &&
             !strcmp(value,  ifnamebuf)) {
             snprintf(iName, sizeof(iName), "%s", value);
         }
 
-        if (!strcmp(name, "if_up") && !strcmp(value, "true")) {
-            printf ("Interface %s is up\n", iName);
-            bound = true;
+        if (!strncmp(name, reason, strlen(reason)) &&
+            !strncmp(value, bound_str, strlen(bound_str))) {
+            printf ("Interface %s bounded\n", iName);
+            bound = 1;
         }
         
         if (bound) {
             // as there is no ntp-support in rtems-libbsd, we call our own client
-            if (!strcmp(name, "new_ntp_servers"))
+            char const * new_ntp_servers = "new_ntp_servers";
+            char const * new_host_name = "new_host_name";
+            char const * new_tftp_server_name = "new_tftp_server_name";
+            
+            if (!strncmp(name, new_ntp_servers, strlen(new_ntp_servers)))
                 snprintf(rtemsInit_NTP_server_ip,
                          sizeof(rtemsInit_NTP_server_ip),
                          "%s", value);
             
-            if (!strcmp(name, "new_host_name"))
+            if (!strncmp(name, new_host_name, strlen(new_host_name)))
                 sethostname (value, strlen (value));
             
-            if (!strcmp(name, "new_tftp_server_name")) {
+            if (!strncmp(name, new_tftp_server_name, strlen(new_tftp_server_name))){
                 snprintf(rtems_bsdnet_bootp_server_name,
                          sizeof(bootp_server_name_init),
                          "%s", value);
                 printf(" rtems_bsdnet_bootp_server_name : %s\n", rtems_bsdnet_bootp_server_name);
             }
-            if(!strcmp(name, "new_bootfile_name")){
+            if(!strncmp(name, "new_bootfile_name", 20)){
                 snprintf(rtems_bsdnet_bootp_boot_file_name,
                          sizeof(bootp_boot_file_name_init),
                          "%s", value);
                 printf(" rtems_bsdnet_bootp_boot_file_name : %s\n", rtems_bsdnet_bootp_boot_file_name);
             }
-            if(!strcmp(name, "new_rtems_cmdline")){
+            if(!strncmp(name, "new_rtems_cmdline", 20)){
                 snprintf(rtems_bsdnet_bootp_cmdline,
                          sizeof(bootp_cmdline_init),
                          "%s", value);