solidity-security

[AUTO-INVOKE] MUST be invoked BEFORE writing or modifying any Solidity contract (.sol files). Covers private key handling, access control, reentrancy prevention, gas safety, and pre-audit checklists. Trigger: any task involving creating, editing, or reviewing .sol source files.

Safety Notice

This listing is imported from skills.sh public index metadata. Review upstream SKILL.md and repository scripts before running.

Copy this and send it to your AI assistant to learn

Install skill "solidity-security" with this command: npx skills add 0xlayerghost/solidity-agent-kit/0xlayerghost-solidity-agent-kit-solidity-security

Solidity Security Standards

Language Rule

  • Always respond in the same language the user is using. If the user asks in Chinese, respond in Chinese. If in English, respond in English.

Private Key Protection

  • Store private keys in .env, load via source .env — never pass keys as CLI arguments
  • Never expose private keys in logs, screenshots, conversations, or commits
  • Provide .env.example with placeholder values for team reference
  • Add .env to .gitignore — verify with git status before every commit

Security Decision Rules

When writing or reviewing Solidity code, apply these rules:

SituationRequired Action
External ETH/token transferUse ReentrancyGuard + Checks-Effects-Interactions (CEI) pattern
ERC20 token interactionUse SafeERC20 — call safeTransfer / safeTransferFrom, never raw transfer / transferFrom
Owner-only functionInherit Ownable2Step (preferred) or Ownable from OZ 4.9.x — Ownable2Step prevents accidental owner loss
Multi-role accessUse AccessControl from @openzeppelin/contracts/access/AccessControl.sol
Token approvalUse safeIncreaseAllowance / safeDecreaseAllowance from SafeERC20 — never raw approve
Price data neededUse Chainlink AggregatorV3Interface if feed exists; otherwise TWAP with min-liquidity check — never use spot pool price directly
Upgradeable contractPrefer UUPS (UUPSUpgradeable) over TransparentProxy; always use Initializable
Solidity version < 0.8.0Must use SafeMath — but strongly prefer upgrading to 0.8.20+
Emergency scenarioInherit Pausable, add whenNotPaused to user-facing functions; keep admin/emergency functions unpaused
Whitelist / airdropUse MerkleProof for gas-efficient verification — never store full address lists on-chain
Signature-based authUse ECDSA + EIP712 — never roll custom signature verification
Signature contentSignature must bind chainId + nonce + msg.sender + deadline — prevent replay and cross-chain reuse
Cross-chain bridge / third-party dependencyAudit all inherited third-party contract code — never assume dependencies are safe
Deprecated / legacy contractsPermanently pause or selfdestruct deprecated contracts — never leave unused contracts callable on-chain
UUPS upgrade pattern_authorizeUpgrade must have onlyOwner; implementation constructor calls _disableInitializers(); retain onlyProxy on upgradeToEVMbench/basin H-01
Multi-contract trust boundaryRouter/Registry relay calls must verify source contract authorization; never trust caller identity inside flash loan callbacks — EVMbench/noya H-08
Counter/ID + external callAll counter increments and ID assignments must complete before external calls; ETH refunds must be last — EVMbench/phi H-06

Reentrancy Protection

  • All contracts with external calls: inherit ReentrancyGuard, add nonReentrant modifier
    • Import: @openzeppelin/contracts/security/ReentrancyGuard.sol (OZ 4.9.x)
  • Always apply CEI pattern even with ReentrancyGuard:
    1. Checks — validate all conditions (require)
    2. Effects — update state variables
    3. Interactions — external calls last

Input Validation

  • Reject address(0) for all address parameters
  • Reject zero amounts for fund transfers
  • Validate array lengths match when processing paired arrays
  • Bound numeric inputs to reasonable ranges (prevent dust attacks, gas griefing)

Gas Control

  • Deployment commands must include --gas-limit (recommended >= 3,000,000)
  • Monitor gas with forge test --gas-report — review before every PR
  • Configure optimizer in foundry.toml: optimizer = true, optimizer_runs = 200
  • Avoid unbounded loops over dynamic arrays — use pagination or pull patterns

Pre-Audit Checklist

Before submitting code for review or audit, verify:

Access & Control:

  • All external/public functions have nonReentrant where applicable
  • No tx.origin used for authentication (use msg.sender)
  • No delegatecall to untrusted addresses
  • Owner transfer uses Ownable2Step (not Ownable) to prevent accidental loss
  • Contracts with user-facing functions inherit Pausable with pause() / unpause()
  • UUPS _authorizeUpgrade has onlyOwner modifier — EVMbench/basin H-01
  • Implementation constructor calls _disableInitializers()EVMbench/basin H-01
  • Router/Registry relay operations verify source contract authorization — EVMbench/noya H-08

Token & Fund Safety:

  • All ERC20 interactions use SafeERC20 (safeTransfer / safeTransferFrom)
  • No raw token.transfer() or require(token.transfer()) patterns
  • Token approvals use safeIncreaseAllowance, not raw approve
  • All external call return values checked

Code Quality:

  • Events emitted for every state change
  • No hardcoded addresses — use config or constructor params
  • .env is in .gitignore

Oracle & Price (if applicable):

  • Price data sourced from Chainlink feed or TWAP — never raw spot price
  • Oracle has minimum liquidity check — revert if pool reserves too low
  • Price deviation circuit breaker in place

Testing:

  • forge test passes with zero failures
  • forge coverage shows adequate coverage on security-critical paths
  • Fuzz tests cover arithmetic edge cases (zero, max uint, boundary values)

Security Verification Commands

# Run all tests with gas report
forge test --gas-report

# Fuzz testing with higher runs for critical functions
forge test --fuzz-runs 10000

# Check test coverage
forge coverage

# Dry-run deployment to verify no runtime errors
forge script script/Deploy.s.sol --fork-url $RPC_URL -vvvv

# Static analysis (if slither installed locally)
slither src/

Slither MCP Integration (if available)

When slither MCP is configured, prefer it over the CLI for structured analysis:

ApproachWhen to Use
slither src/ (CLI)Quick local scan, raw terminal output
slither MCP get_detector_resultsStructured results with impact/confidence filtering, AI can parse and reason about findings
slither MCP get_contract_metadataUnderstanding contract structure before reviewing code
slither MCP get_function_sourceLocating exact function implementations faster than grep

Recommended: Use slither MCP when working with AI agents (results are structured and actionable). Use CLI for quick local checks during development.

Graceful degradation: If neither slither MCP nor slither CLI is available, rely on the Pre-Audit Checklist above and forge test --fuzz-runs 10000 for coverage.

Source Transparency

This detail page is rendered from real SKILL.md content. Trust labels are metadata-based hints, not a safety guarantee.

Related Skills

Related by shared tags or category signals.

Security

defi-security

No summary provided by upstream source.

Repository SourceNeeds Review
Security

solidity-audit

No summary provided by upstream source.

Repository SourceNeeds Review
Automation

solidity-testing

No summary provided by upstream source.

Repository SourceNeeds Review