sshrc is invoked by the SSH server for each successful incoming SSH session in a similar manner to a profile or rc rile for shells.
The system-wide sshrc file is located at /etc/ssh/sshrc
Individual users may have their own sshrc files at ~/.ssh/sshrc or ~/.ssh/rc
https://man7.org/linux/man-pages/man1/ssh.1.html
https://man7.org/linux/man-pages/man8/sshd.8.html#SSHRC