NOTE: This post has been archived for historical purposes. The toolchain has advanced considerably, and Apple is planning to release their own SDK. I plan to hold out on further development, toolchain or otherwise, until it's released.
Please see iPhone Toolchain Project for up-to-date instructions.
To facilitate my own iPhone development, I've committed three new ports for the iphone-binutils project to MacPorts. Once installed, you're ready to compile Hello, World. Prior to installation, you'll need to acquire a copy of the iPhone root disk image ("Heavenly") and install its contents in /opt/local/arm-apple-darwin/heavenly. The image is required to provide the necessary libraries for linking cross-compiled iPhone binaries, and can't be re-distributed.
To start, download and decompress iPhone1,1_1.0_1A543a_Restore.ipsw:
user@host> curl -O http://appldnld.apple.com.edgesuite.net/content.info.apple.com/iPhone/061-3538.20070629.B7vXa/iPhone1,1_1.0_1A543a_Restore.ipsw user@host> unzip iPhone1,1_1.0_1A543a_Restore.ipsw \*.dmg
This will extract two disk images: "694-5259-38.dmg" and "694-5262-39.dmg". The encrypted "694-5262-39.dmg" disk image contains the iPhone root. The decryption key for this image is stored in plain text within the "asr" binary on the corresponding "694-5259-38.dmg". To retrieve the key, run the following:
user@host> strings 694-5259-38.dmg| grep "^[0-9a-fA-F]*$" | awk '{ if (length($1) == 72) print; }'
This should output a 72 character hex string, which you'll use as the decryption key.
In order to perform the decryption, you'll need modified 'vfdecrypt' -- a command utility for decrypting Mac OS X disk images. The source is available here. To compile, simply type "make" in the vfdecrypt-iphone directory. The provided version of vfdecrypt was slightly modified to support direct input of the private AES and SHA1 HMAC keys -- these are normally wrapped with a user-supplied passphrase (via 3DES-EDE), which is not available. vfdecrypt was written by Ralf-Philipp Weinmann, Jacob Appelbaum, and Christian Fromme.
Once you've build vfdecrypt, use it to decrypt the disk image:
user@host> ~/vfdecrypt-iphone/vfdecrypt -i 694-5262-39.dmg -k <hex key> -o heavenly.dmg
Now, mount the disk image and copy the contents to /opt/local/arm-apple-darwin/heavenly:
user@host> open heavenly.dmg user@host> sudo mkdir -p /opt/local/arm-apple-darwin/heavenly user@host> (cd /Volumes/Heavenly1A543a.UserBundle && tar cf - .) | (cd /opt/local/arm-apple-darwin/heavenly && sudo tar xvf -)
To install the toolchain:
sudo port install arm-apple-darwin-runtime
You should now be able to compile standard Unix software:
CC=arm-apple-darwin-cc CPP=llvm-cpp ./configure --host=arm-apple-darwin
For more information on compiling your first GUI application, check out the UIKit Hello World