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Add JA3 raw fingerprint to event logs #3

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Merged
0x4D31 merged 2 commits into from
Aug 1, 2025
Merged

Add JA3 raw fingerprint to event logs #3

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0edd517
Add JA3 raw fingerprint to events
0x4D31 Aug 1, 2025
717a558
rename hb to ch
0x4D31 Aug 1, 2025
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1 change: 1 addition & 0 deletions docs/sse-client.html
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Original file line number Diff line number Diff line change
Expand Up @@ -114,6 +114,7 @@
<div class="metadata">${highlight(`${src} → :${port}${path}`,kw)}</div>
<div class="details">
${detailHTML('JA3', m.ja3 || '—', kw)}
${detailHTML('JA3R', m.ja3Raw || '—', kw)}
${detailHTML('JA4', m.ja4 || '—', kw)}
${detailHTML('JA4H', m.ja4h || '—', kw)}
${detailHTML('HTTP2', m.http2 || '—', kw)}
Expand Down
10 changes: 10 additions & 0 deletions internal/fingerprint/context.go
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Original file line number Diff line number Diff line change
Expand Up @@ -6,13 +6,16 @@ import (
"net/http"

fp "github.com/0x4D31/fingerproxy/pkg/fingerprint"
fpja3 "github.com/0x4D31/fingerproxy/pkg/ja3"
fpja4h "github.com/0x4D31/fingerproxy/pkg/ja4h"
"github.com/0x4D31/fingerproxy/pkg/metadata"
"github.com/dreadl0ck/tlsx"
)

// RequestCtx contains request metadata needed for rule evaluation.
type RequestCtx struct {
JA3 string
JA3Raw string
JA4 string
JA4H string
HTTP2 string
Expand Down Expand Up @@ -50,6 +53,12 @@ func New(r *http.Request) (RequestCtx, error) {
if err != nil {
return RequestCtx{}, err
}
ch := &tlsx.ClientHelloBasic{}
if err := ch.Unmarshal(md.ClientHelloRecord); err != nil {
return RequestCtx{}, err
}
ja3Raw := string(fpja3.Bare(ch))

ja4, err := fp.JA4Fingerprint(md)
if err != nil {
return RequestCtx{}, err
Expand All @@ -62,6 +71,7 @@ func New(r *http.Request) (RequestCtx, error) {
}

ctx.JA3 = ja3
ctx.JA3Raw = ja3Raw
ctx.JA4 = ja4
ctx.JA4H = ja4h
ctx.HTTP2 = http2fp
Expand Down
1 change: 1 addition & 0 deletions internal/logger/jsonl.go
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Expand Up @@ -33,6 +33,7 @@ type Event struct {
ProtocolVersion string `json:"protocolVersion"`
UserAgent string `json:"userAgent"`
JA3 string `json:"ja3"`
JA3Raw string `json:"ja3Raw"`
JA4 string `json:"ja4"`
JA4H string `json:"ja4h"`
HTTP2 string `json:"http2"`
Expand Down
3 changes: 3 additions & 0 deletions internal/proxy/echo.go
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Expand Up @@ -52,6 +52,7 @@ type detailResponse struct {
type summaryResponse struct {
UserAgent string `json:"userAgent"`
JA3 string `json:"ja3"`
JA3Raw string `json:"ja3Raw"`
JA4 string `json:"ja4"`
JA4H string `json:"ja4h"`
HTTP2 string `json:"http2"`
Expand Down Expand Up @@ -156,6 +157,7 @@ func echoHandler(w http.ResponseWriter, r *http.Request) {
resp := summaryResponse{
UserAgent: r.UserAgent(),
JA3: ctx.JA3,
JA3Raw: ctx.JA3Raw,
JA4: ctx.JA4,
JA4H: ctx.JA4H,
HTTP2: ctx.HTTP2,
Expand All @@ -169,6 +171,7 @@ func echoHandler(w http.ResponseWriter, r *http.Request) {
resp := summaryResponse{
UserAgent: r.UserAgent(),
JA3: ctx.JA3,
JA3Raw: ctx.JA3Raw,
JA4: ctx.JA4,
JA4H: ctx.JA4H,
HTTP2: ctx.HTTP2,
Expand Down
2 changes: 2 additions & 0 deletions internal/proxy/server.go
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Expand Up @@ -592,6 +592,7 @@ func (h *ruleHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
ProtocolVersion: r.Proto,
UserAgent: r.UserAgent(),
JA3: reqCtx.JA3,
JA3Raw: reqCtx.JA3Raw,
JA4: reqCtx.JA4,
JA4H: reqCtx.JA4H,
HTTP2: reqCtx.HTTP2,
Expand Down Expand Up @@ -619,6 +620,7 @@ func (h *ruleHandler) ServeHTTP(w http.ResponseWriter, r *http.Request) {
ProtocolVersion: ev.ProtocolVersion,
UserAgent: ev.UserAgent,
JA3: ev.JA3,
JA3Raw: ev.JA3Raw,
JA4: ev.JA4,
JA4H: ev.JA4H,
HTTP2: ev.HTTP2,
Expand Down