{"assessments":[],"deployments":[],"fuzz":[],"identity":{"adapter":"0xde152afb7db5373f34876e1499fbd893a82dd336","chainId":1,"collection":"0x0000ec93127baa929e58e97dd0095a2bfb38ec1d","registry":"0x8004a169fb4a3325136eb29fa0ceb6d2e539a432"},"interpretation":"Records acceptance and evidence. Neither completion nor an AI assessment establishes correctness, safety, or independent review.","jobId":"6952d0ab-db9c-405b-b443-c3c537e71501","kind":"skill:research-report","nodes":[{"acceptedSubmissionHash":"1fa4447dad16d5505790e89fa46d4e1d9c09e982167017bb5c5d9d248d22853b","dependsOn":[],"execution":{"network":true,"profile":"none","requires":["network"],"skillHash":"3ddca93330036359dd721585e58e67820336a0398b7927b3c89369d6134f30f6","skillId":"research-report","tools":[]},"key":"research_report","kind":"code","role":"implement","skillHash":"3ddca93330036359dd721585e58e67820336a0398b7927b3c89369d6134f30f6","skillId":"research-report","state":"accepted"}],"objective":"[SIMD-COLLISION:ripemd160:24]\nFind a collision for ripemd160 truncated to the first 48 bits (λ=24).\nReturn a JSON file named collision.json with exactly:\n{\"algo\":\"ripemd160\",\"lambda\":24,\"inputA\":\"<hex 0x... or utf8>\",\"inputB\":\"<hex 0x... or utf8>\"}\nRules:\n- inputA and inputB must be distinct\n- digest(ripemd160, inputA) and digest(ripemd160, inputB), truncated to 48 bits MSB, must be identical\n- Do not invent a false collision; verification is recomputed by SIMD\nBirthday cost is about 2^24 evaluations.","parentJobId":null,"planHash":"db8cf59269792af61e6af2b5ee3f86a9745dd031d74535fb14290fe873f6a5ff","previousHash":"0000000000000000000000000000000000000000000000000000000000000000","projectId":"6952d0ab-db9c-405b-b443-c3c537e71501","publication":{"commit":null,"deliveredAt":null,"repoUrl":null},"receiptIdentity":{"adapter":"0xde152afb7db5373f34876e1499fbd893a82dd336","chainId":1,"collection":"0x0000ec93127baa929e58e97dd0095a2bfb38ec1d","registry":"0x8004a169fb4a3325136eb29fa0ceb6d2e539a432"},"registry":"0xb6d0a187b050fa5bb0b87033a203f37becf4a775","research":[],"schema":"identitymd-work-v1","signals":[{"agentId":"51091","feedbackHash":"56fb627f565188f2f105137feb148370b7a492e96845ef81c2aecc2ba1094029","nodeKey":"research_report","submissionHash":"1fa4447dad16d5505790e89fa46d4e1d9c09e982167017bb5c5d9d248d22853b","tag1":"verification:structural","tag2":"acceptance-v2","value":1}],"site":null,"snapshotHash":"47d06909ad16fc3f93bd59fe6bdb9fd47dde251d9dc0946faf8c1aac7d96a144","state":"completed","submissions":[{"artifacts":[{"bytes":3949,"hash":"c78f9b128aafb7a449ca111375431afa47c36c10795c0744396fa772e7ee3275","mediaType":"text/markdown","name":"report","path":"artifacts/report.md"}],"attempt":1,"bundleHash":"e18a724f60b84c66521cc10f6aebc73a36f624d75c25975a100909f418f64e2a","device":"9704b5b521bdf559","findings":[],"hash":"1fa4447dad16d5505790e89fa46d4e1d9c09e982167017bb5c5d9d248d22853b","nodeId":"0ad804fc-0017-4347-a5ad-965fcf58aeac","outcome":"completed","summary":"I'll start by checking the environment — available tools, CPU, memory, and repo layout.Empty repo, 2 cores, ~3.8GB free RAM, gcc available. Now let me check whether RIPEMD-160 is available via OpenSSL/Python for independent verification.`hashlib` supports ripemd160 — that gives me an independent oracle to check my C implementation against. Let me set up the workspace.OpenSSL CLI and `hashlib` agree — I have a solid oracle (`ripemd160(\"abc\") = 8eb208f7e05d987a9b044a8e98c6b087f15a0bfc`). \n\nPlan: write an independent RIPEMD-160 in C, validate it against published vectors + OpenSSL, then run a birthday search (~2^24 evals expected) over 8-byte counter inputs, storing truncated digests in an open-addressing table.Now the self-test, a CLI hasher, and the collision search program.Compile and run the self-test.All 9 official vectors pass. Now a randomized cross-check against `hashlib` on arbitrary binary inputs to rule out subtle padding/endianness bugs.Implementation verified — 300/300 random inputs match OpenSSL. Now run the birthday search (expected ~2^24.3 ≈ 17M evaluations).Collision found after ~23.2M evaluations in 7.6s. Now verify it independently with Python `hashlib` and the OpenSSL CLI.Verified by a second implementation. Now add the durable pieces: a Makefile, a verifier script, README, and the report.Run a clean end-to-end check via the Makefile, then commit the source.Bug in my verifier: λ=24 means 48 bits total → 12 hex chars, not `2*λ` hex chars. Fixing.All checks pass. Now commit the source files (outputs stay untracked per the delivery rules).No git identity configured — I'll pass it per-command without modifying config.Done. Verified collision found and delivered.\n\n**Result** (`collision.json`):\n```json\n{\"algo\":\"ripemd160\",\"lambda\":24,\"inputA\":\"0x000000000162a52d\",\"inputB\":\"0x0000000000de27bb\"}\n```\n\n- `ripemd160(inputA)` = `18573a938b62ac143bea6201e8a91fb007aa02ad`\n- `ripemd160(inputB)` = `18573a938b62f83d5fd18457e6667947098926a1`\n- Shared 48-bit MSB prefix: `18573a938b62` — inputs distinct, digests differ after byte 6.\n\n**How it was produced.** Classical birthday search over 8-byte big-endian counter inputs (distinct by construction), storing the top 48 digest bits in a 2^26-slot open-addressed table. Found after 23,242,030 evaluations (~7.6 s) — in line with the ~2^24.3 birthday bound.\n\n**Verification.** The search uses an independent C implementation of RIPEMD-160 (`src/ripemd160.c`) validated against all 9 official test vectors plus 300 random inputs cross-checked against OpenSSL — zero mismatches. The collision itself was re-verified with a different implementation (`hashlib`/OpenSSL) via `tools/verify_collision.py`: `make check` passes end-to-end. `bin/collide 26` is deterministic and regenerates the same pair.\n\n**Deliverables.**\n- `collision.json` — untracked output, exact required schema\n- `artifacts/report.md` — report with method, evidence, and facts/inference/uncertainty separated\n- Committed source: `src/` (hash, self-test, search, CLI), `tools/verify_collision.py`, `Makefile`, `README.md`\n","treeHash":"ca032caf4f29ef90671e810f5058eafd1a1274c2","usage":{"cachedInputTokens":0,"inputTokens":0,"model":"swe-2-high","outputTokens":0,"runtime":"codex","turns":1,"wallClockMs":190732}}],"verification":[{"checks":[],"detail":"paths and tree verified; no suite was run for this kind of work","evaluation":"structural","profile":"none","status":"accepted","submissionHash":"1fa4447dad16d5505790e89fa46d4e1d9c09e982167017bb5c5d9d248d22853b","verifiedTreeHash":"ca032caf4f29ef90671e810f5058eafd1a1274c2","verifierVersion":"0.1.0+41305fb5"}]}