How to modify traffic in a corporate network?

Question

Squid

Greetings!
There is a small building. network (about 20 clients), there was a task to embed arbitrary html into a list of 5-7 sites (a small block with text)
The task is as follows:
- All clients access the Internet via squid + sslbump, certificates are created and installed in trusted authorities, which include logs requests
- You can set it up as you like, but it is desirable to minimally touch client machines (for obvious reasons)
Are there any ready-made solutions for injecting html code through squid? In which direction to dig?
Thanks in advance for your reply

Answer 1

Did a similar task. Only there was a redirect to the page (for a number of sites), where it was possible, after reading, to go further (or refuse).
Implemented was squid + squidguard (possible without it) + self-written python rewriter and a little shamanism.

Answer 2

On squid, I didn't manage to do that in due time. I had to use privoxy, which can modify the content.

Answer 3

the most correct thing to look at is ICAP.. less correct - ACL.. and not at all correct - code hack. in general, the recipe with ICAP is simple - we raise the server, write the signature, modify it in the right direction.