Make mg_http_upload() use predefined upload path

cesanta · Feb 4, 2024 · 89c1c9a · 89c1c9a
1 parent e4bfb2b
commit 89c1c9a
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Showing 6 changed files with 26 additions and 48 deletions.
diff --git a/examples/file-upload-multiple-posts/main.c b/examples/file-upload-multiple-posts/main.c
@@ -10,7 +10,17 @@ static void cb(struct mg_connection *c, int ev, void *ev_data) {
   if (ev == MG_EV_HTTP_MSG) {
     struct mg_http_message *hm = (struct mg_http_message *) ev_data;
     if (mg_http_match_uri(hm, "/upload")) {
-      mg_http_upload(c, hm, &mg_fs_posix, "/tmp", 99999);
+      const char *tempfile = "/tmp/upload.data";
+      long res = mg_http_upload(c, hm, &mg_fs_posix, tempfile, 99999);
+      if (res == 0) {
+        // Upload finished. Rename temprorary file into a target one
+        char path[80], file[64];
+        mg_http_get_var(&hm->query, "file", file, sizeof(file));
+        mg_snprintf(path, sizeof(path), "/tmp/%s", file);
+        if (mg_path_is_sane(path)) {
+          mg_fs_posix.mv(tempfile, path);
+        }
+      }
     } else {
       struct mg_http_serve_opts opts = {.root_dir = "web_root"};
       mg_http_serve_dir(c, ev_data, &opts);

diff --git a/mongoose.c b/mongoose.c
@@ -3134,28 +3134,20 @@ bool mg_http_match_uri(const struct mg_http_message *hm, const char *glob) {
 }
 
 long mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
-                    struct mg_fs *fs, const char *dir, size_t max_size) {
-  char buf[20] = "0", file[40], path[MG_PATH_MAX];
+                    struct mg_fs *fs, const char *path, size_t max_size) {
+  char buf[20] = "0";
   long res = 0, offset;
   mg_http_get_var(&hm->query, "offset", buf, sizeof(buf));
-  mg_http_get_var(&hm->query, "file", file, sizeof(file));
   offset = strtol(buf, NULL, 0);
-  mg_snprintf(path, sizeof(path), "%s%c%s", dir, MG_DIRSEP, file);
   if (hm->body.len == 0) {
     mg_http_reply(c, 200, "", "%ld", res);  // Nothing to write
-  } else if (file[0] == '\0') {
-    mg_http_reply(c, 400, "", "file required");
-    res = -1;
-  } else if (mg_path_is_sane(file) == false) {
-    mg_http_reply(c, 400, "", "%s: invalid file", file);
-    res = -2;
   } else if (offset < 0) {
     mg_http_reply(c, 400, "", "offset required");
-    res = -3;
+    res = -1;
   } else if ((size_t) offset + hm->body.len > max_size) {
     mg_http_reply(c, 400, "", "%s: over max size of %lu", path,
         (unsigned long) max_size);
-    res = -4;
+    res = -2;
   } else {
     struct mg_fd *fd;
     size_t current_size = 0;
@@ -3164,10 +3156,10 @@ long mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
     fs->st(path, &current_size, NULL);
     if (offset > 0 && current_size != (size_t) offset) {
       mg_http_reply(c, 400, "", "%s: offset mismatch", path);
-      res = -5;
+      res = -3;
     } else if ((fd = mg_fs_open(fs, path, MG_FS_WRITE)) == NULL) {
       mg_http_reply(c, 400, "", "open(%s): %d", path, errno);
-      res = -6;
+      res = -4;
     } else {
       res = offset + (long) fs->wr(fd->fd, hm->body.ptr, hm->body.len);
       mg_fs_close(fd);

diff --git a/mongoose.h b/mongoose.h
@@ -2287,7 +2287,7 @@ size_t mg_url_encode(const char *s, size_t n, char *buf, size_t len);
 void mg_http_creds(struct mg_http_message *, char *, size_t, char *, size_t);
 bool mg_http_match_uri(const struct mg_http_message *, const char *glob);
 long mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
-                    struct mg_fs *fs, const char *dir, size_t max_size);
+                    struct mg_fs *fs, const char *path, size_t max_size);
 void mg_http_bauth(struct mg_connection *, const char *user, const char *pass);
 struct mg_str mg_http_get_header_var(struct mg_str s, struct mg_str v);
 size_t mg_http_next_multipart(struct mg_str, size_t, struct mg_http_part *);

diff --git a/src/http.c b/src/http.c
@@ -918,28 +918,20 @@ bool mg_http_match_uri(const struct mg_http_message *hm, const char *glob) {
 }
 
 long mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
-                    struct mg_fs *fs, const char *dir, size_t max_size) {
-  char buf[20] = "0", file[40], path[MG_PATH_MAX];
+                    struct mg_fs *fs, const char *path, size_t max_size) {
+  char buf[20] = "0";
   long res = 0, offset;
   mg_http_get_var(&hm->query, "offset", buf, sizeof(buf));
-  mg_http_get_var(&hm->query, "file", file, sizeof(file));
   offset = strtol(buf, NULL, 0);
-  mg_snprintf(path, sizeof(path), "%s%c%s", dir, MG_DIRSEP, file);
   if (hm->body.len == 0) {
     mg_http_reply(c, 200, "", "%ld", res);  // Nothing to write
-  } else if (file[0] == '\0') {
-    mg_http_reply(c, 400, "", "file required");
-    res = -1;
-  } else if (mg_path_is_sane(file) == false) {
-    mg_http_reply(c, 400, "", "%s: invalid file", file);
-    res = -2;
   } else if (offset < 0) {
     mg_http_reply(c, 400, "", "offset required");
-    res = -3;
+    res = -1;
   } else if ((size_t) offset + hm->body.len > max_size) {
     mg_http_reply(c, 400, "", "%s: over max size of %lu", path,
         (unsigned long) max_size);
-    res = -4;
+    res = -2;
   } else {
     struct mg_fd *fd;
     size_t current_size = 0;
@@ -948,10 +940,10 @@ long mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
     fs->st(path, &current_size, NULL);
     if (offset > 0 && current_size != (size_t) offset) {
       mg_http_reply(c, 400, "", "%s: offset mismatch", path);
-      res = -5;
+      res = -3;
     } else if ((fd = mg_fs_open(fs, path, MG_FS_WRITE)) == NULL) {
       mg_http_reply(c, 400, "", "open(%s): %d", path, errno);
-      res = -6;
+      res = -4;
     } else {
       res = offset + (long) fs->wr(fd->fd, hm->body.ptr, hm->body.len);
       mg_fs_close(fd);

diff --git a/src/http.h b/src/http.h
@@ -59,7 +59,7 @@ size_t mg_url_encode(const char *s, size_t n, char *buf, size_t len);
 void mg_http_creds(struct mg_http_message *, char *, size_t, char *, size_t);
 bool mg_http_match_uri(const struct mg_http_message *, const char *glob);
 long mg_http_upload(struct mg_connection *c, struct mg_http_message *hm,
-                    struct mg_fs *fs, const char *dir, size_t max_size);
+                    struct mg_fs *fs, const char *path, size_t max_size);
 void mg_http_bauth(struct mg_connection *, const char *user, const char *pass);
 struct mg_str mg_http_get_header_var(struct mg_str s, struct mg_str v);
 size_t mg_http_next_multipart(struct mg_str, size_t, struct mg_http_part *);

diff --git a/test/unit_test.c b/test/unit_test.c
@@ -681,7 +681,7 @@ static void eh1(struct mg_connection *c, int ev, void *ev_data) {
       mg_http_creds(hm, user, sizeof(user), pass, sizeof(pass));
       mg_http_reply(c, 200, "", "[%s]:[%s]", user, pass);
     } else if (mg_http_match_uri(hm, "/upload")) {
-      mg_http_upload(c, hm, &mg_fs_posix, ".", 99999);
+      mg_http_upload(c, hm, &mg_fs_posix, "./uploaded.txt", 99999);
       c->is_hexdumping = 1;
     } else if (mg_http_match_uri(hm, "/test/")) {
       struct mg_http_serve_opts sopts;
@@ -1062,10 +1062,6 @@ static void test_http_server(void) {
     char *p;
     remove("uploaded.txt");
     ASSERT((p = mg_file_read(&mg_fs_posix, "uploaded.txt", NULL)) == NULL);
-    ASSERT(fetch(&mgr, buf, url,
-                 "POST /upload HTTP/1.0\n"
-                 "Content-Length: 1\n\nx") == 400);
-
     ASSERT(fetch(&mgr, buf, url,
                  "POST /upload?file=uploaded.txt HTTP/1.0\r\n"
                  "Content-Length: 5\r\n"
@@ -1080,18 +1076,6 @@ static void test_http_server(void) {
     remove("uploaded.txt");
   }
 
-  {
-    // Test upload directory traversal
-    char *p;
-    remove("uploaded.txt");
-    ASSERT((p = mg_file_read(&mg_fs_posix, "uploaded.txt", NULL)) == NULL);
-    ASSERT(fetch(&mgr, buf, url,
-                 "POST /upload?file=../uploaded.txt HTTP/1.0\r\n"
-                 "Content-Length: 5\r\n"
-                 "\r\nhello") == 400);
-    ASSERT((p = mg_file_read(&mg_fs_posix, "uploaded.txt", NULL)) == NULL);
-  }
-
   // HEAD request
   ASSERT(fetch(&mgr, buf, url, "GET /a.txt HTTP/1.0\n\n") == 200);
   ASSERT(fetch(&mgr, buf, url, "HEAD /a.txt HTTP/1.0\n\n") == 200);