fix(csp): append nonce alongside existing directives instead of stripping 'unsafe-inline'#3885
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sanjibani wants to merge 1 commit into
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fix(csp): append nonce alongside existing directives instead of stripping 'unsafe-inline'#3885sanjibani wants to merge 1 commit into
sanjibani wants to merge 1 commit into
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…ping 'unsafe-inline' Closes freshframework#3813 The csp middleware used replaceAll() to substitute any "'unsafe-inline'" with the per-request nonce, which forced the strict-CSP pattern that strips the fallback. This is exactly the wrong direction: web.dev's recommended strict-CSP fallback is to keep "'unsafe-inline'" alongside the nonce so older browsers that ignore nonces still work, while modern browsers prefer the nonce. Now the middleware simply appends the nonce to each inline directive (script-src, style-src, default-src, script-src-elem, style-src-elem, style-src-attr), preserving whatever the user wrote (including their "'unsafe-inline'" fallback). The default "'unsafe-inline'" entries remain in the rendered header alongside the nonce, matching the production pattern used by e.g. YouTube. Tests updated to assert the append behaviour; two new tests cover the explicit-fallback case and the strict-no-unsafe-inline case.
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Closes #3813
The csp middleware used
replaceAll()to substitute any'unsafe-inline'with the per-request nonce, which forced the strict-CSP pattern that strips the fallback. This is the wrong direction: web.dev's recommended strict-CSP fallback is to keep'unsafe-inline'alongside the nonce so older browsers that ignore nonces still work, while modern browsers prefer the nonce.This changes the middleware to simply append the nonce to each inline directive (script-src, style-src, default-src, script-src-elem, style-src-elem, style-src-attr), preserving whatever the user wrote — including their
'unsafe-inline'fallback. The default'unsafe-inline'entries remain in the rendered header alongside the nonce, matching the production pattern used by e.g. YouTube.Tests updated to assert the append behaviour; two new tests cover the explicit-fallback case (web.dev strict-CSP pattern) and the strict-no-unsafe-inline case. The doc page at
docs/latest/plugins/csp.mdis updated to reflect the new semantics and link to the web.dev fallback guide.