How can I work around Subversion's port being blocked when installing something with brew? I'm running into an issue where I'm trying to follow the advice of a comment on this SO Q&amp;A titled: Use PPK file in Mac Terminal to connect to remote connection over SSH that suggested you could install putty via an Subversion repository like so:

$ brew install putty --HEAD


When attempted I get this error:

$ brew install putty --HEAD
==&gt; Cloning svn://svn.tartarus.org/sgt/putty
svn: E000060: Unable to connect to a repository at URL 'svn://svn.tartarus.org/sgt/putty'
svn: E000060: Can't connect to host 'svn.tartarus.org': Operation timed out
Error: Failed to download resource "putty"
Failure while executing: svn checkout -q --force svn://svn.tartarus.org/sgt/putty /Library/Caches/Homebrew/putty--svn-HEAD


NOTE #1: I believe the port used by Subversion is blocked by a corporate firewall.

NOTE #2: I'm ultimately trying to work around an issue with the version of putty that's included in Brew.

$ brew install putty
==&gt; Downloading https://homebrew.bintray.com/bottles/putty-0.63.yosemite.bottle.tar.gz
Already downloaded: /Library/Caches/Homebrew/putty-0.63.yosemite.bottle.tar.gz
==&gt; Pouring putty-0.63.yosemite.bottle.tar.gz
  /usr/local/Cellar/putty/0.63: 11 files, 1.4M

$ puttygen privatekey.ppk -O private-openssh -o privatekey.pem
Enter passphrase to load key:
Assertion failed: (random_active), function random_byte, file ./unix/../sshrand.c, line 313.
Abort trap: 6
Run puttygen as sudo and you'll be fine.