diff --git a/sys/conf/files b/sys/conf/files
--- a/sys/conf/files
+++ b/sys/conf/files
@@ -4099,6 +4099,7 @@
 libkern/strncmp.c		standard
 libkern/strncpy.c		standard
 libkern/strnlen.c		standard
+libkern/strnstr.c		standard
 libkern/strrchr.c		standard
 libkern/strsep.c		standard
 libkern/strspn.c		standard
diff --git a/sys/sys/libkern.h b/sys/sys/libkern.h
--- a/sys/sys/libkern.h
+++ b/sys/sys/libkern.h
@@ -186,6 +186,7 @@
 int	 strncmp(const char *, const char *, size_t);
 char	*strncpy(char * __restrict, const char * __restrict, size_t);
 size_t	 strnlen(const char *, size_t);
+char	*strnstr(const char *, const char *, size_t);
 char	*strrchr(const char *, int);
 char	*strsep(char **, const char *delim);
 size_t	 strspn(const char *, const char *);