CFE-3294: carry the secret tag across the bundle parameter boundary - #6328
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nickanderson wants to merge 5 commits into
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CFE-3294: carry the secret tag across the bundle parameter boundary#6328nickanderson wants to merge 5 commits into
nickanderson wants to merge 5 commits into
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EvalContextVariableGet() always returned the plaintext value, so a caller had no way to ask for a secret-tagged variable to be redacted. Adds a get_secret parameter and *Plaintext wrappers, and moves every existing caller onto the plaintext form. No behaviour change: every call site asks for plaintext, exactly as before. Ticket: CFE-3293 Changelog: None
EvalContextVariableGet() kept the variable's declared type while returning the redacted scalar sentinel, so an indexed read of a secret-tagged container -- mydata[key] -- took the container branch and handed that string to RvalContainerValue(), which aborts with a ProgrammingError. Deriving the type from the value actually being returned fixes it and removes the separate type_out special case. Not reachable yet: no caller passes get_secret=false until the CFE-3294 work. test_secret_container_redacts_indexed_read aborts (SIGABRT) without this and passes with it, and asserts the plaintext reads still work so redaction cannot be faked by breaking container reads. Ticket: CFE-3293 Changelog: None
VARIABLE_TAG_SECRET was a private #define in variable.c, so no code outside that file could ask whether a variable is secret -- which is what every caller that copies a value into a new variable has to do before it can propagate the tag. Moves the constant to variable.h and adds EvalContextVariableIsTaggedSecret() next to EvalContextVariableTags(). Answering via a tag set means allocating one to test a single membership, so this goes straight through VariableResolve(). No behaviour change on its own; the propagation commits that follow use it. Ticket: CFE-3294 Changelog: None
A variable whose value references a secret-tagged variable now inherits the tag, so "laundered" string => "$(password)" is no longer an ordinary variable holding plaintext that every reporting and logging path can read. Reads the value from pp->org_pp rather than the constraint the verify function is given: promises are fully expanded before verification, so by then the "$(password)" reference this keys on has already become its value. Runs on every pass, because a copy written untagged in an earlier pass stays readable for the rest of that pass. Adds FindSecretVariableReferences() in vars.c. Its traversal deliberately mirrors ExpandScalar()'s rather than factoring out a shared iterator -- restructuring a function that central does not belong in a leak fix, but the duplication is real and worth revisiting separately. Only scalar values are inspected, so a list or container assembled out of secrets does not inherit the tag yet. Ticket: CFE-3294 Changelog: Title
ScopeAugment() read each argument with the plaintext accessor and published the callee's copy with a hardcoded "source=promise" tag list, so passing a secret-tagged list or container into a bundle laundered it: the callee's copy was an ordinary variable and getvalues() returned the plaintext. Both call sites are the two branches of one if/else feeding the same switch, so both needed the tag lookup. The test asserts both directions -- the secret container must be redacted in the callee AND a non-secret container must still arrive intact -- so "no plaintext" cannot be satisfied by breaking parameter passing. Ticket: CFE-3294 Changelog: Title
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ScopeAugment()published each bundle argument into the callee's scope with ahardcoded
"source=promise"tag list, so passing a secret-tagged list or containerinto a bundle laundered it — the callee's copy was an ordinary variable. The tag now
propagates across the parameter boundary.
Both call sites needed it: they are the two branches of one if/else feeding the same
switch.
Stacked on #6327.