diff --git a/app/Http/Controllers/Api/Admin/AdminMenuController.php b/app/Http/Controllers/Api/Admin/AdminMenuController.php
index ef62282..ac7201a 100644
--- a/app/Http/Controllers/Api/Admin/AdminMenuController.php
+++ b/app/Http/Controllers/Api/Admin/AdminMenuController.php
@@ -23,6 +23,12 @@ class AdminMenuController extends Controller
                     'title' => '赛事列表',
                     'permissionCode' => 'competition.read',
                 ],
+                [
+                    'name' => 'admin-public-source-channels',
+                    'path' => 'public-source-channels',
+                    'title' => '公开来源渠道',
+                    'permissionCode' => 'competition.read',
+                ],
                 ['section' => '评审管理'],
                 [
                     'name' => 'admin-reviewers-list',
diff --git a/app/Http/Controllers/Api/Admin/PublicSourceChannelController.php b/app/Http/Controllers/Api/Admin/PublicSourceChannelController.php
new file mode 100644
index 0000000..7b86fa2
--- /dev/null
+++ b/app/Http/Controllers/Api/Admin/PublicSourceChannelController.php
@@ -0,0 +1,116 @@
+<?php
+
+namespace App\Http\Controllers\Api\Admin;
+
+use App\Http\Controllers\Controller;
+use App\Models\PublicSourceChannel;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Http\Request;
+use Illuminate\Http\Response;
+use Illuminate\Validation\Rule;
+
+class PublicSourceChannelController extends Controller
+{
+    public function index(Request $request): JsonResponse
+    {
+        $channels = PublicSourceChannel::query()
+            ->orderByDesc('id')
+            ->get()
+            ->map(fn (PublicSourceChannel $channel) => $this->toRow($channel, $request))
+            ->values();
+
+        return response()->json(['data' => $channels]);
+    }
+
+    public function store(Request $request): JsonResponse
+    {
+        $data = $request->validate([
+            'source_code' => [
+                'required',
+                'string',
+                'min:2',
+                'max:64',
+                'regex:/^[A-Za-z0-9_-]{2,64}$/',
+                Rule::unique('public_source_channels', 'source_code'),
+            ],
+            'source_name' => ['required', 'string', 'min:1', 'max:100'],
+            'status' => ['sometimes', Rule::in(PublicSourceChannel::STATUSES)],
+        ]);
+
+        $channel = PublicSourceChannel::query()->create([
+            'source_code' => trim($data['source_code']),
+            'source_name' => trim($data['source_name']),
+            'status' => $data['status'] ?? PublicSourceChannel::STATUS_ENABLED,
+        ]);
+
+        return response()->json($this->toRow($channel, $request), 201);
+    }
+
+    public function show(Request $request, PublicSourceChannel $publicSourceChannel): JsonResponse
+    {
+        return response()->json($this->toRow($publicSourceChannel, $request));
+    }
+
+    public function update(Request $request, PublicSourceChannel $publicSourceChannel): JsonResponse
+    {
+        $data = $request->validate([
+            'source_code' => [
+                'sometimes',
+                'string',
+                'min:2',
+                'max:64',
+                'regex:/^[A-Za-z0-9_-]{2,64}$/',
+                Rule::unique('public_source_channels', 'source_code')->ignore($publicSourceChannel->id),
+            ],
+            'source_name' => ['sometimes', 'string', 'min:1', 'max:100'],
+            'status' => ['sometimes', Rule::in(PublicSourceChannel::STATUSES)],
+        ]);
+
+        if (array_key_exists('source_code', $data)) {
+            $publicSourceChannel->source_code = trim($data['source_code']);
+        }
+        if (array_key_exists('source_name', $data)) {
+            $publicSourceChannel->source_name = trim($data['source_name']);
+        }
+        if (array_key_exists('status', $data)) {
+            $publicSourceChannel->status = $data['status'];
+        }
+        $publicSourceChannel->save();
+
+        return response()->json($this->toRow($publicSourceChannel, $request));
+    }
+
+    public function destroy(PublicSourceChannel $publicSourceChannel): Response
+    {
+        $publicSourceChannel->status = PublicSourceChannel::STATUS_DISABLED;
+        $publicSourceChannel->save();
+
+        return response()->noContent();
+    }
+
+    /**
+     * @return array<string, mixed>
+     */
+    private function toRow(PublicSourceChannel $channel, Request $request): array
+    {
+        return [
+            'id' => $channel->id,
+            'source_code' => $channel->source_code,
+            'source_name' => $channel->source_name,
+            'status' => $channel->status,
+            'entry_url' => $this->entryUrl($channel, $request),
+            'created_at' => $channel->created_at?->toIso8601String(),
+            'updated_at' => $channel->updated_at?->toIso8601String(),
+        ];
+    }
+
+    private function entryUrl(PublicSourceChannel $channel, Request $request): string
+    {
+        $base = trim((string) config('public_source.frontend_url'));
+        if ($base === '') {
+            $base = $request->getSchemeAndHttpHost();
+        }
+
+        return rtrim($base, '/').'/?src='.rawurlencode($channel->source_code);
+    }
+}
diff --git a/app/Http/Controllers/Api/AuthSmsController.php b/app/Http/Controllers/Api/AuthSmsController.php
index 53ae997..18d7dab 100644
--- a/app/Http/Controllers/Api/AuthSmsController.php
+++ b/app/Http/Controllers/Api/AuthSmsController.php
@@ -5,6 +5,7 @@ namespace App\Http\Controllers\Api;
 use App\Http\Controllers\Controller;
 use App\Models\Application;
 use App\Models\Competition;
+use App\Models\PublicSourceChannel;
 use App\Models\SmsVerification;
 use App\Models\User;
 use App\Services\Sms\ParticipantSmsVerificationService;
@@ -53,6 +54,9 @@ class AuthSmsController extends Controller
             'code' => ['required', 'string', 'max:64'],
             'competition_slug' => ['required', 'string', 'max:64'],
         ]);
+        $data['public_source_code'] = is_string($request->input('public_source_code'))
+            ? (string) $request->input('public_source_code')
+            : '';
 
         $verification = SmsVerification::query()
             ->where('scene', SmsVerification::SCENE_PARTICIPANT_LOGIN)
@@ -100,6 +104,10 @@ class AuthSmsController extends Controller
                 ['name' => null, 'email' => null, 'password' => null]
             );
 
+            if ($user->wasRecentlyCreated) {
+                $this->attributePublicSource($user, (string) ($data['public_source_code'] ?? ''));
+            }
+
             Application::query()->firstOrCreate(
                 [
                     'user_id' => $user->id,
@@ -134,6 +142,29 @@ class AuthSmsController extends Controller
         ]);
     }
 
+    private function attributePublicSource(User $user, string $sourceCode): void
+    {
+        $sourceCode = trim($sourceCode);
+        if (! preg_match('/^[A-Za-z0-9_-]{2,64}$/', $sourceCode)) {
+            return;
+        }
+
+        $channel = PublicSourceChannel::query()
+            ->where('source_code', $sourceCode)
+            ->where('status', PublicSourceChannel::STATUS_ENABLED)
+            ->first();
+
+        if ($channel === null) {
+            return;
+        }
+
+        $user->forceFill([
+            'public_source_channel_id' => $channel->id,
+            'public_source_code' => $channel->source_code,
+            'public_source_attributed_at' => now(),
+        ])->save();
+    }
+
     private function expirePreviousVerifications(string $mobile, int $currentId): void
     {
         SmsVerification::query()
diff --git a/app/Http/Controllers/Api/PublicSourceChannelController.php b/app/Http/Controllers/Api/PublicSourceChannelController.php
new file mode 100644
index 0000000..a832e3f
--- /dev/null
+++ b/app/Http/Controllers/Api/PublicSourceChannelController.php
@@ -0,0 +1,34 @@
+<?php
+
+namespace App\Http\Controllers\Api;
+
+use App\Http\Controllers\Controller;
+use App\Models\PublicSourceChannel;
+use Illuminate\Http\JsonResponse;
+use Illuminate\Http\Request;
+
+class PublicSourceChannelController extends Controller
+{
+    public function resolve(Request $request): JsonResponse
+    {
+        $sourceCode = trim((string) $request->query('source_code', ''));
+        if (! preg_match('/^[A-Za-z0-9_-]{2,64}$/', $sourceCode)) {
+            return response()->json(['valid' => false]);
+        }
+
+        $channel = PublicSourceChannel::query()
+            ->where('source_code', $sourceCode)
+            ->where('status', PublicSourceChannel::STATUS_ENABLED)
+            ->first();
+
+        if ($channel === null) {
+            return response()->json(['valid' => false]);
+        }
+
+        return response()->json([
+            'valid' => true,
+            'source_code' => $channel->source_code,
+            'source_name' => $channel->source_name,
+        ]);
+    }
+}
diff --git a/app/Models/PublicSourceChannel.php b/app/Models/PublicSourceChannel.php
new file mode 100644
index 0000000..42a1fb3
--- /dev/null
+++ b/app/Models/PublicSourceChannel.php
@@ -0,0 +1,37 @@
+<?php
+
+namespace App\Models;
+
+use Illuminate\Database\Eloquent\Factories\HasFactory;
+use Illuminate\Database\Eloquent\Model;
+use Illuminate\Database\Eloquent\Relations\HasMany;
+
+class PublicSourceChannel extends Model
+{
+    use HasFactory;
+
+    public const STATUS_ENABLED = 'enabled';
+
+    public const STATUS_DISABLED = 'disabled';
+
+    public const STATUSES = [
+        self::STATUS_ENABLED,
+        self::STATUS_DISABLED,
+    ];
+
+    protected $fillable = [
+        'source_code',
+        'source_name',
+        'status',
+    ];
+
+    public function users(): HasMany
+    {
+        return $this->hasMany(User::class, 'public_source_channel_id');
+    }
+
+    public function isEnabled(): bool
+    {
+        return $this->status === self::STATUS_ENABLED;
+    }
+}
diff --git a/app/Models/User.php b/app/Models/User.php
index ffb1da6..d7ca88e 100644
--- a/app/Models/User.php
+++ b/app/Models/User.php
@@ -31,6 +31,9 @@ class User extends Authenticatable
         'last_channel_id',
         'last_channel_code',
         'last_channel_entered_at',
+        'public_source_channel_id',
+        'public_source_code',
+        'public_source_attributed_at',
     ];
 
     public function application()
@@ -53,6 +56,11 @@ class User extends Authenticatable
         return $this->belongsTo(SignupChannel::class, 'last_channel_id');
     }
 
+    public function publicSourceChannel(): BelongsTo
+    {
+        return $this->belongsTo(PublicSourceChannel::class, 'public_source_channel_id');
+    }
+
     /**
      * The attributes that should be hidden for serialization.
      *
@@ -73,5 +81,6 @@ class User extends Authenticatable
         'password' => 'hashed',
         'first_channel_entered_at' => 'datetime',
         'last_channel_entered_at' => 'datetime',
+        'public_source_attributed_at' => 'datetime',
     ];
 }
diff --git a/config/public_source.php b/config/public_source.php
new file mode 100644
index 0000000..42c175a
--- /dev/null
+++ b/config/public_source.php
@@ -0,0 +1,5 @@
+<?php
+
+return [
+    'frontend_url' => env('PUBLIC_FRONTEND_URL'),
+];
diff --git a/database/migrations/2026_06_07_100000_create_public_source_channels_table.php b/database/migrations/2026_06_07_100000_create_public_source_channels_table.php
new file mode 100644
index 0000000..224a4d7
--- /dev/null
+++ b/database/migrations/2026_06_07_100000_create_public_source_channels_table.php
@@ -0,0 +1,25 @@
+<?php
+
+use App\Models\PublicSourceChannel;
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::create('public_source_channels', function (Blueprint $table) {
+            $table->id();
+            $table->string('source_code', 64)->unique();
+            $table->string('source_name', 100);
+            $table->string('status')->default(PublicSourceChannel::STATUS_ENABLED);
+            $table->timestamps();
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::dropIfExists('public_source_channels');
+    }
+};
diff --git a/database/migrations/2026_06_07_101000_add_public_source_to_users_table.php b/database/migrations/2026_06_07_101000_add_public_source_to_users_table.php
new file mode 100644
index 0000000..52429a5
--- /dev/null
+++ b/database/migrations/2026_06_07_101000_add_public_source_to_users_table.php
@@ -0,0 +1,33 @@
+<?php
+
+use Illuminate\Database\Migrations\Migration;
+use Illuminate\Database\Schema\Blueprint;
+use Illuminate\Support\Facades\Schema;
+
+return new class extends Migration
+{
+    public function up(): void
+    {
+        Schema::table('users', function (Blueprint $table) {
+            $table->foreignId('public_source_channel_id')
+                ->nullable()
+                ->after('last_channel_entered_at')
+                ->constrained('public_source_channels')
+                ->nullOnDelete();
+            $table->string('public_source_code', 64)->nullable()->after('public_source_channel_id');
+            $table->timestamp('public_source_attributed_at')->nullable()->after('public_source_code');
+        });
+    }
+
+    public function down(): void
+    {
+        Schema::table('users', function (Blueprint $table) {
+            $table->dropForeign(['public_source_channel_id']);
+            $table->dropColumn([
+                'public_source_channel_id',
+                'public_source_code',
+                'public_source_attributed_at',
+            ]);
+        });
+    }
+};
diff --git a/routes/api.php b/routes/api.php
index a6476ff..81c296b 100644
--- a/routes/api.php
+++ b/routes/api.php
@@ -6,6 +6,7 @@ use App\Http\Controllers\Api\Admin\AuthController as AdminAuthController;
 use App\Http\Controllers\Api\Admin\CompetitionController as AdminCompetitionController;
 use App\Http\Controllers\Api\Admin\CompetitionTrackController as AdminCompetitionTrackController;
 use App\Http\Controllers\Api\Admin\FormSchemaDefinitionController as AdminFormSchemaDefinitionController;
+use App\Http\Controllers\Api\Admin\PublicSourceChannelController as AdminPublicSourceChannelController;
 use App\Http\Controllers\Api\Admin\ReviewerController as AdminReviewerController;
 use App\Http\Controllers\Api\Admin\ReviewerScopeController as AdminReviewerScopeController;
 use App\Http\Controllers\Api\Admin\SignupChannelController as AdminSignupChannelController;
@@ -13,6 +14,7 @@ use App\Http\Controllers\Api\ApplicationController;
 use App\Http\Controllers\Api\ApplicationFileController;
 use App\Http\Controllers\Api\AuthSmsController;
 use App\Http\Controllers\Api\PublicCompetitionController;
+use App\Http\Controllers\Api\PublicSourceChannelController;
 use App\Http\Controllers\Api\ReviewApplicationController;
 use App\Http\Controllers\Api\ReviewAuthController;
 use App\Http\Controllers\Api\UserProfileController;
@@ -20,6 +22,7 @@ use Illuminate\Support\Facades\Route;
 
 Route::prefix('v1')->group(function () {
     Route::get('public/competitions/by-slug/{slug}', [PublicCompetitionController::class, 'showBySlug']);
+    Route::get('public/source-channels/resolve', [PublicSourceChannelController::class, 'resolve']);
 
     Route::prefix('review')->group(function () {
         Route::post('auth/login', [ReviewAuthController::class, 'login']);
@@ -42,6 +45,10 @@ Route::prefix('v1')->group(function () {
         Route::middleware(['auth:sanctum', 'admin'])->group(function () {
             Route::get('me/menus', [AdminMenuController::class, 'index']);
             Route::get('competitions/{competition}/reviewer-scope-track-counts', [AdminReviewerScopeController::class, 'countsByTrack']);
+            Route::apiResource('public-source-channels', AdminPublicSourceChannelController::class)
+                ->parameters([
+                    'public-source-channels' => 'public_source_channel',
+                ]);
             Route::apiResource('competitions', AdminCompetitionController::class);
             /** scoped() 无参即可；切勿写 `'track' => 'tracks'`，Laravel 会把 `tracks` 当成子表列名导致 SQL 错误 */
             Route::apiResource('competitions.tracks', AdminCompetitionTrackController::class)->scoped();
diff --git a/tests/Feature/AuthSmsControllerTest.php b/tests/Feature/AuthSmsControllerTest.php
index 5567533..09915ff 100644
--- a/tests/Feature/AuthSmsControllerTest.php
+++ b/tests/Feature/AuthSmsControllerTest.php
@@ -3,6 +3,7 @@
 namespace Tests\Feature;
 
 use App\Models\Competition;
+use App\Models\PublicSourceChannel;
 use App\Models\SmsVerification;
 use App\Support\SmsConfig;
 use Illuminate\Database\Schema\Blueprint;
@@ -92,6 +93,112 @@ class AuthSmsControllerTest extends TestCase
         ])->assertUnprocessable();
     }
 
+    public function test_public_source_resolve_and_registration_attribution(): void
+    {
+        $this->competition('main-event');
+        $sourceA = PublicSourceChannel::query()->create([
+            'source_code' => 'poster_A',
+            'source_name' => '海报 A',
+            'status' => PublicSourceChannel::STATUS_ENABLED,
+        ]);
+        $sourceB = PublicSourceChannel::query()->create([
+            'source_code' => 'poster_B',
+            'source_name' => '海报 B',
+            'status' => PublicSourceChannel::STATUS_ENABLED,
+        ]);
+        PublicSourceChannel::query()->create([
+            'source_code' => 'closed_src',
+            'source_name' => '停用渠道',
+            'status' => PublicSourceChannel::STATUS_DISABLED,
+        ]);
+
+        $this->getJson('/api/v1/public/source-channels/resolve?source_code=poster_A')
+            ->assertOk()
+            ->assertJsonPath('valid', true)
+            ->assertJsonPath('source_name', '海报 A');
+
+        $this->getJson('/api/v1/public/source-channels/resolve?source_code=closed_src')
+            ->assertOk()
+            ->assertJsonPath('valid', false);
+        $this->getJson('/api/v1/public/source-channels/resolve?source_code=bad%20code')
+            ->assertOk()
+            ->assertJsonPath('valid', false);
+
+        SmsVerification::query()->create([
+            'scene' => SmsVerification::SCENE_PARTICIPANT_LOGIN,
+            'mobile' => '13800138100',
+            'code' => '111111',
+            'provider' => SmsVerification::PROVIDER_DISABLED,
+            'status' => SmsVerification::STATUS_SENT,
+            'expires_at' => now()->addMinutes(5),
+        ]);
+
+        $this->postJson('/api/auth/sms/login', [
+            'mobile' => '13800138100',
+            'code' => '111111',
+            'competition_slug' => 'main-event',
+            'public_source_code' => 'poster_A',
+        ])->assertOk();
+
+        $this->assertDatabaseHas('users', [
+            'mobile' => '13800138100',
+            'public_source_channel_id' => $sourceA->id,
+            'public_source_code' => 'poster_A',
+        ]);
+        $this->assertNotNull(DB::table('users')
+            ->where('mobile', '13800138100')
+            ->value('public_source_attributed_at'));
+
+        SmsVerification::query()->create([
+            'scene' => SmsVerification::SCENE_PARTICIPANT_LOGIN,
+            'mobile' => '13800138100',
+            'code' => '222222',
+            'provider' => SmsVerification::PROVIDER_DISABLED,
+            'status' => SmsVerification::STATUS_SENT,
+            'expires_at' => now()->addMinutes(5),
+        ]);
+
+        $this->postJson('/api/auth/sms/login', [
+            'mobile' => '13800138100',
+            'code' => '222222',
+            'competition_slug' => 'main-event',
+            'public_source_code' => 'poster_B',
+        ])->assertOk();
+
+        $this->assertDatabaseHas('users', [
+            'mobile' => '13800138100',
+            'public_source_channel_id' => $sourceA->id,
+            'public_source_code' => 'poster_A',
+        ]);
+        $this->assertDatabaseMissing('users', [
+            'mobile' => '13800138100',
+            'public_source_channel_id' => $sourceB->id,
+            'public_source_code' => 'poster_B',
+        ]);
+
+        SmsVerification::query()->create([
+            'scene' => SmsVerification::SCENE_PARTICIPANT_LOGIN,
+            'mobile' => '13800138101',
+            'code' => '333333',
+            'provider' => SmsVerification::PROVIDER_DISABLED,
+            'status' => SmsVerification::STATUS_SENT,
+            'expires_at' => now()->addMinutes(5),
+        ]);
+
+        $this->postJson('/api/auth/sms/login', [
+            'mobile' => '13800138101',
+            'code' => '333333',
+            'competition_slug' => 'main-event',
+            'public_source_code' => 'bad code',
+        ])->assertOk();
+
+        $this->assertDatabaseHas('users', [
+            'mobile' => '13800138101',
+            'public_source_channel_id' => null,
+            'public_source_code' => null,
+        ]);
+    }
+
     public function test_enabled_sender_fails_fast_when_app_key_is_missing(): void
     {
         config([
@@ -547,6 +654,17 @@ class AuthSmsControllerTest extends TestCase
             $table->string('email')->nullable();
             $table->string('company')->nullable();
             $table->string('password')->nullable();
+            $table->foreignId('public_source_channel_id')->nullable();
+            $table->string('public_source_code', 64)->nullable();
+            $table->timestamp('public_source_attributed_at')->nullable();
+            $table->timestamps();
+        });
+
+        Schema::create('public_source_channels', function (Blueprint $table) {
+            $table->id();
+            $table->string('source_code', 64)->unique();
+            $table->string('source_name', 100);
+            $table->string('status')->default(PublicSourceChannel::STATUS_ENABLED);
             $table->timestamps();
         });