Artifact [75b38460fc]

Artifact 75b38460fcf09012c653cbee856f07c5a7a3062e8db3dd561b7c40b41b3b399a:

• File internal/sync/auth.go — part of check-in [f5744359d3] at 2026-04-19 16:30:54 on branch trunk — Initial open source release

  libfossil is a pure-Go implementation of the Fossil SCM, reading and writing the same .fossil SQLite repository format as upstream Fossil.

  This is the first public release of code that previously lived in a private repository. The module path is github.com/danmestas/libfossil and the binary is named libfossil to avoid $PATH collisions with upstream fossil.

  Included: - Repo lifecycle (create, clone), checkout/checkin, timeline, merge, diff, annotate, shun, tag, branch, bisect, stash, undo/redo - Sync-over-HTTP protocol (client and handler) - Two SQLite drivers: modernc (pure Go, default) and ncruces (wasm-capable) - Observer interfaces (SyncObserver, CheckoutObserver) with an optional OpenTelemetry implementation in observer/otel (separate submodule) - Deterministic simulation testing harness with BUGGIFY fault injection - Kong-based embeddable CLI under cli/ and a standalone binary under cmd/libfossil/ (user: [email protected], size: 1239) [annotate] [blame] [check-ins using]

package sync

import (
	"crypto/sha1"
	"encoding/hex"
	"fmt"

	"github.com/danmestas/libfossil/simio"
	"github.com/danmestas/libfossil/internal/xfer"
)

// computeLogin produces a LoginCard for the given credentials.
// payload is the encoded bytes of all non-login cards (including random comment).
func computeLogin(user, password, projectCode string, payload []byte) *xfer.LoginCard {
	if user == "" {
		panic("sync.computeLogin: user must not be empty")
	}
	if projectCode == "" {
		panic("sync.computeLogin: projectCode must not be empty")
	}
	if payload == nil {
		panic("sync.computeLogin: payload must not be nil")
	}
	nonce := sha1Hex(payload)
	sharedSecret := sha1Hex([]byte(projectCode + "/" + user + "/" + password))
	signature := sha1Hex([]byte(nonce + sharedSecret))
	return &xfer.LoginCard{User: user, Nonce: nonce, Signature: signature}
}

// appendRandomComment appends "# <random-hex>\n" to payload for nonce uniqueness.
func appendRandomComment(payload []byte, rng simio.Rand) []byte {
	rb := make([]byte, 20)
	rng.Read(rb)
	comment := fmt.Sprintf("# %s\n", hex.EncodeToString(rb))
	return append(payload, []byte(comment)...)
}

func sha1Hex(data []byte) string {
	h := sha1.Sum(data)
	return hex.EncodeToString(h[:])
}