OpenWRT SDK Error

Dear, I am facing issues with OpenWRT/LEDE-SDK-17 I am trying to build software of ShadwVPN & Minivtun but I am getting below error,

library.c:16:25: fatal error: openssl/evp.h: No such file or directory
compilation terminated.
Makefile:19: recipe for target 'library.o' failed
make[4]: *** [library.o] Error 1
make[4]: Leaving directory '/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64/build_dir/target-mips_24kc_musl-1.1.16/minivtun/minivtun-1.0.1-1a1eda256e536f5af698fa00abd22cb9a6b4f0e9/src'
Makefile:44: recipe for target '/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64/build_dir/target-mips_24kc_musl-1.1.16/minivtun//minivtun-1.0.1-1a1eda256e536f5af698fa00abd22cb9a6b4f0e9/.built' failed
make[3]: *** [/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64/build_dir/target-mips_24kc_musl-1.1.16/minivtun//minivtun-1.0.1-1a1eda256e536f5af698fa00abd22cb9a6b4f0e9/.built] Error 2
make[3]: Leaving directory '/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64/package/minivtun-openwrt'
package/Makefile:105: recipe for target 'package/minivtun-openwrt/compile' failed
make[2]: *** [package/minivtun-openwrt/compile] Error 2
make[2]: Leaving directory '/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64'
package/Makefile:101: recipe for target '/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64/staging_dir/target-mips_24kc_musl-1.1.16/stamp/.package_compile' failed
make[1]: *** [/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64/staging_dir/target-mips_24kc_musl-1.1.16/stamp/.package_compile] Error 2
make[1]: Leaving directory '/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64'
/root/lede-sdk-17.01.7-ar71xx-generic_gcc-5.4.0_musl-1.1.16.Linux-x86_64/include/toplevel.mk:198: recipe for target 'world' failed
make: *** [world] Error 2

As I feel its openssl error but I have install openssl properly, after I get that error I have install again but still didn't succeed to build my software, Please help me to solve this problem. Thank you....