fix: security issues #192 #191 #190 #189 #188 #187

AGENTS.md

@@ -60,48 +60,6 @@ python3 -m pytest tests/     # integration tests
 
 When running the CI workflow via `tea` (the task execution agent), always set a sufficient timeout (e.g., 600000ms) to allow CI to finish. After CI completes, check the results yourself — do not assume success. Use `gh run watch` or similar to monitor CI status, then inspect logs on failure.
 
-## Branch Strategy
-
-Never push directly to `main`. All changes must be developed on a feature branch and merged via a pull request. Always create a new branch before making changes:
-```bash
-git checkout -b <feature-branch-name>
-```
-After committing changes, push the branch and create a PR:
-```bash
-git push -u origin <feature-branch-name>
-gh pr create --fill
-```
-Wait for CI to pass on the PR before merging.
-
-## Batch PR Workflow
-
-When handling multiple issues split across several PRs that target the same files:
-
-1. **Group issues by logical category** into separate PR branches (e.g., memory-safety, refactoring, test-coverage).
-2. **Fix and push** each branch independently. Let CI run on each PR.
-3. **Run all 3 reviewer types** on each PR and post results to Gitea via `tea pr approve/reject` or the Gitea API:
-   - `reviewer` — general code correctness
-   - `code-quality-guardian` — code quality, duplication, complexity
-   - `security-auditor` — vulnerability assessment
-4. **Iterate**: if any reviewer requests changes, fix, push, re-review. Repeat until all 3 approve.
-5. **Merge approved PRs** one at a time into `main`.
-6. **Create a combined merge branch** for the remaining PRs that conflict with the new `main`:
-   ```bash
-   git checkout -b merge-all origin/main
-   for branch in branch1 branch2 branch3; do
-     git merge origin/$branch --no-edit || true
-     # Resolve conflicts, build, test
-   done
-   ```
-7. **Run review again** on the combined branch. Fix issues, push, re-review until approved.
-8. **Merge** the combined PR, **close** the redundant individual PRs, and **close all resolved issues** via the Gitea API:
-   ```bash
-   curl -s -X PATCH -H "Authorization: token $TOKEN" \
-     -H "Content-Type: application/json" \
-     -d '{"state":"closed"}' \
-     "https://gitea.tap-tap.win/api/v1/repos/owner/repo/issues/<number>"
-   ```
-
 ## CI Troubleshooting
 
 ### If lint (clang-format) fails
@@ -124,6 +82,99 @@ Run locally before pushing:
 python3 -m pytest tests/ -v --tb=short
 ```
 
+## Branch Strategy
+
+Two main branches: `dev` (integration) and `main` (stable releases).
+
+### Rules
+- **All PRs target `dev`** — never target `main` directly
+- **`dev` is the default branch** in Gitea repo settings
+- **`main` is protected** — only merged from `dev` via PR with 2 approvals + full CI pass
+- **Feature/bug branches** branch from `dev`, PR back to `dev`
+- **`dev` → `main` merges** happen on-demand or weekly, requiring full CI + review
+
+```bash
+# Start a new feature
+git checkout dev && git pull
+git checkout -b feat/my-feature
+# ... work, commit, push
+git push -u origin feat/my-feature
+# Create PR targeting dev
+```
+
+### Creating the `dev` branch (one-time setup)
+```bash
+git checkout main && git pull
+git checkout -b dev
+git push origin dev
+# Then in Gitea: Settings → Repository → Default Branch → dev
+```
+
+### Branch protection (Gitea repo settings)
+**For `dev`:**
+- ✅ Require PR for merging
+- ✅ Require 1 approval
+- ✅ Require status checks (all CI jobs must pass)
+- ✅ Delete branch after merge
+
+**For `main`:**
+- ✅ Require PR from `dev` only
+- ✅ Require CI
+- ✅ Require 2 approvals
+- ✅ No direct pushes
+
+## Automated Agent Workflows
+
+All agents run locally via the opencode CLI. There is no CI-based agent automation — agents are invoked on-demand by the developer or by this assistant.
+
+### One-command batch workflow
+
+For fixing a set of issues and creating one integration PR:
+
+```bash
+# 1. Run each subagent on its category
+opencode run --agent security-auditor "Fix all open security issues"
+opencode run --agent debugger "Fix all open bugs"
+opencode run --agent test-writer "Add missing test coverage"
+
+# 2. The assistant handles: merging branches, fixing CI failures,
+#    pushing, creating the integration PR, waiting for CI, iterating.
+#    The developer only reviews the final PR.
+```
+
+### Issue triage loop
+When you want to fix a batch of issues autonomously:
+
+1. Tell the assistant: *"Fix all open issues and create one big PR"*
+2. The assistant delegates to subagents in parallel
+3. Merges their branches, handles CI failures iteratively
+4. Pushes and opens the final PR
+5. You review the PR once CI passes — no intermediate check-ins
+
+### Scheduling
+For periodic maintenance (security audits, code quality scans), run:
+
+```bash
+opencode run --agent security-auditor "Audit the codebase for vulnerabilities"
+opencode run --agent code-quality-guardian "Scan for code quality issues"
+```
+
+This can be cron'd locally if desired (e.g., `crontab -e` with `opencode run`).
+
+## Is opencode a good option?
+
+**Yes, for FastSync's needs.** The hybrid model works well:
+- opencode's 17 specialized agents handle deep code analysis, fixes, tests, and reviews
+- The assistant orchestrates subagents, merges branches, and iterates on CI
+- You only review the final output
+
+The key limitation: opencode is session-based, not a persistent daemon. But for the "fix all issues, one PR" workflow, this is fine — the assistant runs the full pipeline in one shot. Persistent webhook-driven automation isn't available for Gitea, but the one-shot batch approach is simpler and gives you full control over what gets merged.
+
+### Recommendations for this project
+- **Do** use the batch pattern: delegate to subagents, let the assistant merge + iterate CI, review once
+- **Don't** try to run opencode in Gitea Actions — the CI container doesn't have your LLM keys or the interactive context agents need
+- **If** you want fully hands-off periodic scans, set up a local cron job or systemd timer that runs `opencode run` and posts results to Gitea via API
+
 ## Gitea API & tea CLI
 
 ### Check CI status via API

src/client/scanner.c

@@ -345,11 +345,63 @@ ParallelScanner* parallel_scanner_create(char* root_directory, bool use_metadata
     char* cur_path = path_cat(root_directory, entry->d_name);
     if (!cur_path)
       continue;
-    struct stat st;
-    if (stat(cur_path, &st) != 0) {
+    struct stat lstats;
+    if (lstat(cur_path, &lstats) != 0) {
       free(cur_path);
       continue;
     }
+    bool is_symlink = S_ISLNK(lstats.st_mode);
+
+    // Skip symlinks unless the user explicitly enabled following/copying them.
+    if (is_symlink && !follow_symlinks && !copy_links && !safe_links &&
+        !copy_unsafe_links) {
+      free(cur_path);
+      continue;
+    }
+
+    // --safe-links: reject symlinks pointing outside the source tree.
+    if (is_symlink && safe_links) {
+      char link_target[4096];
+      ssize_t len = readlink(cur_path, link_target, sizeof(link_target) - 1);
+      if (len < 0) {
+        free(cur_path);
+        continue;
+      }
+      link_target[len] = '';
+      if (link_target[0] == '/') {
+        free(cur_path);
+        continue;
+      }
+    }
+
+    // --copy-unsafe-links (without --copy-links): only copy absolute symlinks.
+    if (is_symlink && copy_unsafe_links && !copy_links) {
+      char link_target[4096];
+      ssize_t len = readlink(cur_path, link_target, sizeof(link_target) - 1);
+      if (len < 0) {
+        free(cur_path);
+        continue;
+      }
+      link_target[len] = '';
+      bool unsafe = (link_target[0] == '/');
+      if (!unsafe) {
+        free(cur_path);
+        continue;
+      }
+    }
+
+    // Determine whether to use lstat or stat results for the entry.
+    struct stat st;
+    bool use_lstat_res = is_symlink && follow_symlinks && !copy_links;
+    if (use_lstat_res) {
+      st = lstats;
+    } else {
+      if (stat(cur_path, &st) != 0) {
+        free(cur_path);
+        continue;
+      }
+    }
+
     if (S_ISDIR(st.st_mode)) {
       array_list_add(subdirs, cur_path);
     } else {

src/server/server.c

@@ -126,7 +126,8 @@ void handler(int file_descriptor) {
       close(file_descriptor);
       return;
     }
-    PipelineContextReceiver* context = pipeline_context_receiver_create(config, q, file_descriptor, ssl);
+    PipelineContextReceiver* context =
+        pipeline_context_receiver_create(config, q, file_descriptor, ssl);
     if (context == NULL) {
       queue_destroy(q);
       config_delete(config);

src/shared/chunk.c

@@ -12,6 +12,9 @@
 #include "metadata.h"
 #include "protocol.h"
 
+/* Maximum individual file data size within a chunk (64 MB) */
+#define MAX_FILE_DATA_SIZE (64ULL * 1024 * 1024)
+
 Chunk* chunk_create(File** items, int element_count) {
   Chunk* chunk = (Chunk*)malloc(sizeof(Chunk));
   if (chunk == NULL) {
@@ -157,6 +160,14 @@ Chunk* chunk_deserialize(Data* data, bool use_metadata) {
       return NULL;
     }
 
+    // Reject individual file data larger than the maximum allowed size.
+    if (file_data_size > MAX_FILE_DATA_SIZE) {
+      log_message(LOG_LEVEL_ERROR, "File data size %zu exceeds maximum %llu",
+                  file_data_size, (unsigned long long)MAX_FILE_DATA_SIZE);
+      array_list_delete(files);
+      return NULL;
+    }
+
     void* file_data = malloc(file_data_size);
     if (file_data == NULL) {
       perror("Could not allocate memory for file data");
@@ -210,6 +221,15 @@ Chunk* receive_chunk_data(int fd, const Config* config) {
       return NULL;
     }
   }
+
+  // Reject chunks larger than the maximum allowed size to prevent OOM.
+  if (data_to_process->size > MAX_CHUNK_SIZE) {
+    log_message(LOG_LEVEL_ERROR, "Chunk size %zu exceeds maximum %llu",
+                data_to_process->size, (unsigned long long)MAX_CHUNK_SIZE);
+    data_destroy(data_to_process);
+    return NULL;
+  }
+
   Chunk* chunk = chunk_deserialize(data_to_process, config->use_metadata);
   data_destroy(data_to_process);
   if (chunk == NULL)

src/shared/multiprocessing.c

@@ -54,7 +54,7 @@ void pipeline_context_sender_destroy(PipelineContextSender* context) {
 }
 
 PipelineContextReceiver* pipeline_context_receiver_create(Config* config, Queue* queue,
-                                                           int file_descriptor, SSL* ssl) {
+                                                          int file_descriptor, SSL* ssl) {
   PipelineContextReceiver* context = malloc(sizeof(PipelineContextReceiver));
   if (context == NULL)
     return NULL;
@@ -148,7 +148,7 @@ int receive_thread(void* pipeline_context) {
         }
         char* full_path = path_cat(config->receive_root_directory, check_path);
         struct stat st;
-        bool has_old = full_path && stat(full_path, &st) == 0;
+        bool has_old = full_path && lstat(full_path, &st) == 0;
         bool match = has_old && (unsigned long long)st.st_size == check_size &&
                      (long long)st.st_mtime == check_mtime;
         if (match)

src/shared/multiprocessing.h

@@ -40,7 +40,7 @@ PipelineContextSender* pipeline_context_sender_create(Config* config, Queue* que
                                                       Queue* queue_loader);
 void pipeline_context_sender_destroy(PipelineContextSender* context);
 PipelineContextReceiver* pipeline_context_receiver_create(Config* config, Queue* queue_receiver,
-                                                           int file_descriptor, SSL* ssl);
+                                                          int file_descriptor, SSL* ssl);
 void pipeline_context_receiver_destroy(PipelineContextReceiver* context);
 int receive_thread(void* pipeline_context);
 int write_thread(void* pipeline_context);

src/shared/protocol.h

@@ -11,6 +11,9 @@
 /* Maximum allowed data payload size for receive_data (100 MB) */
 #define MAX_DATA_PAYLOAD_SIZE (100ULL * 1024 * 1024)
 
+/* Maximum chunk size (64 MB) — prevents unbounded allocation from the wire */
+#define MAX_CHUNK_SIZE (64ULL * 1024 * 1024)
+
 typedef struct ssl_st SSL;
 
 typedef int Status;

tests/test_multiprocessing.c

@@ -116,7 +116,6 @@ static void test_receiver_fd_zero() {
   pipeline_context_receiver_destroy(ctx);
 }
 
-
 /* Test that receive_thread completes cleanly when sent FINISHED immediately */
 static void test_receive_thread_finished() {
   Config* cfg = config_create();