Tutorial: iPhone App with compiled OpenSSL Library

This is a tutorial for using self-compiled builds of  the OpenSSL-library on the iPhone. You can build apps with XCode and the official SDK from Apple with this. I also made a small example-app for using the libraries with XCode and the iPhone/iPhone-Simulator. You can also download the precompiled OpenSSL-library (0.9.8m-beta1).

You can get the Source of the example app with compiled OpenSSL at http://github.com/x2on/OpenSSL-for-iPhone

Create OpenSSL Libary:

• Download OpenSSL Sourcecode
• Build OpenSSL for i368 iPhoneSimulator:

  • cd openssl-0.9.8m
    mkdir openssl_arm
    mkdir openssl_i386
    ./config --openssldir=/Users/<username>/openssl-0.9.8m/openssl_i386

  • Edit Makefile:
    • Change CC = cc to:

      CC= /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.0

    • Add as first item to CFLAG:

      -isysroot /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator3.1.2.sdk

  • Change in crypto/ui/ui_openssl.c

    static volatile sig_atomic_t intr_signal;

    to

    static volatile int intr_signal;

    for preventing building error

  • Build it:

    make
    make install

  • Your libcrypto.a and libssl.a are in the folder openssl_i368/lib
  • Rename the two files to libcrypto_i386.a and libssl_i386.a
• Build OpenSSL for arm iPhoneOS:
  • Edit Makefile:
    • Search and replace openssl_i386 with openssl_arm
    • Change -arch i386 in CFLAG to:
      -arch armv6
    • Change

      CC=  /Developer/Platforms/iPhoneSimulator.platform/Developer/usr/bin/gcc-4.0

      to

      CC=  /Developer/Platforms/iPhoneOS.platform/Developer/usr/bin/gcc-4.0

    • Change

      -isysroot  /Developer/Platforms/iPhoneSimulator.platform/Developer/SDKs/iPhoneSimulator3.1.2.sdk

      to

      -isysroot  /Developer/Platforms/iPhoneOS.platform/Developer/SDKs/iPhoneOS3.1.2.sdk

  • Build it:

    make
    make install

  • Your libcrypto.a and libssl.a are in the folder openssl_arm/lib
  • Rename the two files to libcrypto_arm.a and libssl_arm.a

Edit your iPhone-XCode project:

• Copy the “include” folder from OpenSSL into your project-folder
• Copy the libcrypto_*.a and libss_*.a files into your project-folder
• Drag the libcrypto_*.a and libss_*.a files into your XCode Framework Folder-Tree
• Open the Build-Info from your “Target” (Righclick on Target – Get Info)
• Change Library Search Paths to

  $(inherited) "$(SRCROOT)"

• Change User Header Search Paths to include
• Activate Always Search User Paths

Enjoy OpenSSL on the iPhone!

I have made an iPhone OS 3.1.2 XCode Project with OpenSSL 0.9.8m (Beta1) Libaries. The examples uses the MD5-algorithm to calculate an md5 hash from an UITextfield.

Download: OpenSSL-1 iPhone Example Project (2,9MB)

Download: OpenSSL-iPhone-0.9.8m-beta1-i386-arm (2,0MB)

Disclaimer: Use this at your own risk.

Links:

• http://www.therareair.com/2009/01/01/tutorial-how-to-compile-openssl-for-the-iphone/
• http://www.openssl.org/
• http://cocoawithlove.com/2009/06/base64-encoding-options-on-mac-and.html