feat: add cadence script signature

[jaymengxy]

Related Issue

Closes #777

Summary of Changes

Need Regression Testing

• Yes
• No

Risk Assessment

• Low
• Medium
• High

Additional Notes

Screenshots (if applicable)

[github-actions]

PR Summary

Enhanced security by implementing signature verification for Cadence scripts. Added new functionality to verify script authenticity using NIST256P1 public key verification, with proper error handling and reporting. Updated API service to handle signature headers and implemented response body verification.

Changes

File	Summary
app/build.gradle	Added X_SIGNATURE_KEY build config field to store the signature verification key from properties
app/src/main/assets/config/cadence_api.json	Modified configuration file (no visible changes in diff)
app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt	Added signature verification using wallet.core for Cadence scripts. Implemented verifySignature method using NIST256P1 public key, added error handling and reporting for signature verification failures.
app/src/main/java/com/flowfoundation/wallet/network/ApiService.kt	Modified getCadenceScript to getCadenceScriptWithHeaders returning Response<ResponseBody> to access signature headers
app/src/main/java/com/flowfoundation/wallet/utils/error/Error.kt	Added new error types for signature verification: EMPTY_SCRIPT_SIGNATURE, INVALID_SCRIPT_SIGNATURE, SIGNATURE_VERIFICATION_ERROR, DECODE_SCRIPT_FAILED
gradle.properties	Increased version code from 270 to 271
key.properties.example	Added X_SIGNATURE_KEY to the example properties file

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autogenerated by presubmit.ai

[github-actions]

🚨 Pull request needs attention.

Review Summary

Commits Considered (1)

• 00baaf6: feat: add cadence script signature

Files Processed (8)

• app/build.gradle (1 hunk)
• app/src/main/assets/config/cadence_api.json (0 hunks)
• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt (5 hunks)
• app/src/main/java/com/flowfoundation/wallet/network/ApiService.kt (2 hunks)
• app/src/main/java/com/flowfoundation/wallet/utils/error/Error.kt (1 hunk)
• app/src/test/java/com/flowfoundation/wallet/utils/SignatureVerificationTest.kt (1 hunk)
• gradle.properties (1 hunk)
• key.properties.example (1 hunk)

Actionable Comments (2)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [76-77]

  best practice: "Response body is not properly closed after use"

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [141-144]

  possible bug: "Missing validation for signature byte length"

Skipped Comments (1)

• app/src/test/java/com/flowfoundation/wallet/utils/SignatureVerificationTest.kt [68-68]

  maintainability: "Non-ASCII character in error message"

[github-actions]

🚨 Pull request needs attention.

Review Summary

Commits Considered (1)

• f50b581: fix: close response body

Files Processed (1)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt (5 hunks)

Actionable Comments (1)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [130-130]

  security: "Potential security risk in key handling"

Skipped Comments (2)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [160-163]

  best practice: "Avoid printing stack traces to logs"

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [91-97]

  enhancement: "Improve error handling resilience"

[github-actions]

🚨 Pull request needs attention.

Review Summary

Commits Considered (1)

• b6e19b2: fix: close response body

Files Processed (1)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt (5 hunks)

Actionable Comments (2)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [161-162]

  security: "Avoid logging sensitive error details"

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [94-94]

  security: "Avoid exposing error details in logs"

Skipped Comments (1)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [127-127]

  security: "Specify message digest encoding mode"

[github-actions]

🚨 Pull request needs attention.

Review Summary

Commits Considered (1)

• fe993cc: fix: use wallet core verify

Files Processed (1)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt (5 hunks)

Actionable Comments (3)

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [71-76]

  possible bug: "Missing null check for raw response"

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [119-123]

  security: "Potential timing attack vulnerability in signature verification"

• app/src/main/java/com/flowfoundation/wallet/manager/cadence/CadenceApiManager.kt [97-102]

  security: "Missing data validation before parsing"

Skipped Comments (0)