svn list --depth infinity <your-repo-here> to get a list of files in the repo, and then svn cat to get contents. You can add --xml key to list command to make parsing a bit simpler.
If you are using TortoiseSVN you can try this IF you are willing to look Project by Project - works for me:
Create a blank project under your repository top level URL, call it BLANK
Click on the Repo URL on left pane
On the right hand pane select your BLANK project and your desired project - say trunk
Right click to pop up the browser menu and select 'Compare URLs', depending on the size of your repo it may take a minute to load. But you basically get your entire project list in a 'ready-to-search' list.
Enter your file name or other string in the search filter
Recently I've published my utility to list the repository, that's much faster than "svn ls --depth infinity" approach. Here're the benchmarks. It just calls a function that is available in Subversion internal API, but now accessible through a command line.
If your's remote repository is not huge, then an easy method is:
You can do a "checkout" to get a local repository. If you are in windows machine you use "Search" or Linux machine use "Find" command.
Not sure that it's a good idea to use additional tools to filter search results like svn+grep. Such tools like grep or svn-crawler might not be available/work on Windows or other OS, you'll need to install/upgrade them.
You may solve this task using 1 single svn command with --search flag that supports glob pattern:
> svn ls -R --search "readme.md"
branches/0.13.x/readme.md
trunk/readme.md
> svn ls -R --search "*.md"
branches/0.13.x/189.md
branches/0.13.x/readme.md
trunk/189.md
trunk/readme.md
More about svn ls --search option:
> svn ls -h
list (ls): List directory entries in the repository.
usage: list [TARGET[@REV]...]
List each TARGET file and the contents of each TARGET directory as
they exist in the repository. If TARGET is a working copy path, the
corresponding repository URL will be used. If specified, REV determines
in which revision the target is first looked up.
...
Valid options:
...
--search ARG : use ARG as search pattern (glob syntax, case-
and accent-insensitive, may require quotation marks
to prevent shell expansion)