rgw: Rest client header parsing does not use VLAs

Signed-off-by: Adam C. Emerson <aemerson@redhat.com>

diff --git a/src/rgw/rgw_rest_client.cc b/src/rgw/rgw_rest_client.cc
index c442232f8d8542922332627f2e289c6453927aa7..5062875d19f3065fe3a1749a9b0d0f7c09d2f677 100644 (file)
--- a/src/rgw/rgw_rest_client.cc
+++ b/src/rgw/rgw_rest_client.cc
@@ -7,7 +7,6 @@
 #include "rgw_auth_s3.h"
 #include "rgw_http_errors.h"
 
-#include "common/armor.h"
 #include "common/strtol.h"
 #include "include/str_list.h"
 #include "rgw_crypt_sanitize.h"
@@ -26,17 +25,16 @@ int RGWHTTPSimpleRequest::get_status()
   return status;
 }
 
-int RGWHTTPSimpleRequest::handle_header(const string& name, const string& val) 
+int RGWHTTPSimpleRequest::handle_header(std::string_view name, std::string_view val)
 {
   if (name == "CONTENT_LENGTH") {
-    string err;
-    long len = strict_strtol(val.c_str(), 10, &err);
-    if (!err.empty()) {
+    auto len = ceph::parse<std::size_t>(val);
+    if (!len) {
       ldpp_dout(this, 0) << "ERROR: failed converting content length (" << val << ") to int " << dendl;
       return -EINVAL;
     }
 
-    max_response = len;
+    max_response = *len;
   }
 
   return 0;
@@ -46,63 +44,59 @@ int RGWHTTPSimpleRequest::receive_header(void *ptr, size_t len)
 {
   unique_lock guard(out_headers_lock);
 
-  char line[len + 1];
-  char *s = (char *)ptr, *end = (char *)ptr + len;
-  char *p = line;
+  std::string_view line(static_cast<const char*>(ptr), len);
   ldpp_dout(this, 30) << "receive_http_header" << dendl;
 
-  while (s != end) {
-    if (*s == '\r') {
-      s++;
-      continue;
-    }
-    if (*s == '\n') {
-      if (p == line) {
-        // End of headers (empty line "\r\n")
-        ldpp_dout(this, 30) << "All headers received" << dendl;
-        return handle_headers(out_headers, http_status);
-      }
-      *p = '\0';
-      ldpp_dout(this, 30) << "received header: " << line << dendl;
-      // TODO: fill whatever data required here
-      char *l = line;
-      char *tok = strsep(&l, " \t:");
-      if (tok && l) {
-        while (*l == ' ')
-          l++;
-
-        if (strcmp(tok, "HTTP") == 0 || strncmp(tok, "HTTP/", 5) == 0) {
-          http_status = atoi(l);
-          if (http_status == 100) /* 100-continue response */
-            continue;
-          status = rgw_http_error_to_errno(http_status);
-        } else {
-          /* convert header field name to upper case */
-          char *src = tok;
-          char buf[len + 1];
-          size_t i;
-          for (i = 0; i < len && *src; ++i, ++src) {
-            switch (*src) {
-              case '-':
-                buf[i] = '_';
-                break;
-              default:
-                buf[i] = toupper(*src);
-            }
-          }
-          buf[i] = '\0';
-          out_headers[buf] = l;
-          int r = handle_header(buf, l);
-          if (r < 0)
-            return r;
-        }
-      }
-      p = line;
+  if (line == "\r\n" || line == "\n") {
+    // End of headers (empty line "\r\n")
+    ldpp_dout(this, 30) << "All headers received" << dendl;
+    return handle_headers(out_headers, http_status);
+  }
+
+  if (line.ends_with("\r\n")) {
+    line.remove_suffix(2);
+  } else if (line.ends_with("\n")) {
+    line.remove_suffix(1);
+  }
+  ldpp_dout(this, 30) << "received header: " << line << dendl;
+
+  auto trim = [](std::string_view & v) {
+    auto n = v.find_first_not_of(" \t");
+    if (n == v.npos) {
+      v = std::string_view{};
+    } else {
+      v.remove_prefix(n);
     }
-    if (s != end)
-      *p++ = *s++;
+  };
+  trim(line);
+  if (line.empty()) {
+    return 0;
   }
 
+  auto sep = line.find_first_of(" \t:");
+  if (sep == line.npos) {
+    return 0;
+  }
+  auto left = line.substr(0, sep);
+  auto right = line.substr(sep + 1, line.npos);
+  trim(right);
+
+  if (left == "HTTP" || left.starts_with("HTTP/")) {
+    // First line
+    sep = right.find_first_of(" \t");
+    auto status_tok = right.substr(0, sep);
+    // .value_or(0) mimics atol's behavior on receiving no digits.
+    http_status = ceph::parse<std::uint16_t>(status_tok).value_or(0);
+    if (http_status == 100) {
+      return 0;
+    }
+    status = rgw_http_error_to_errno(http_status);
+  } else {
+    std::string header_name;
+    uppercase_dash_transform(left, std::back_inserter(header_name));
+    out_headers[header_name] = std::string{right};
+    return handle_header(header_name, right);
+  }
   return 0;
 }
 
@@ -1010,17 +1004,16 @@ int RGWHTTPStreamRWRequest::handle_headers(const map<string, string>& headers, i
   return 0;
 }
 
-int RGWHTTPStreamRWRequest::handle_header(const string& name, const string& val)
+int RGWHTTPStreamRWRequest::handle_header(std::string_view name, std::string_view val)
 {
   if (name == "RGWX_EMBEDDED_METADATA_LEN") {
-    string err;
-    long len = strict_strtol(val.c_str(), 10, &err);
-    if (!err.empty()) {
+    auto len = ceph::parse<std::uint64_t>(val);
+    if (!len) {
       ldpp_dout(this, 0) << "ERROR: failed converting embedded metadata len (" << val << ") to int " << dendl;
       return -EINVAL;
     }
 
-    cb->set_extra_data_len(len);
+    cb->set_extra_data_len(*len);
   }
   return 0;
 }

diff --git a/src/rgw/rgw_rest_client.h b/src/rgw/rgw_rest_client.h
index 7e68d681f0e9c744c463cfed95bed0874f7810b8..2d30e8313f6d590013fecc30254daf3c4838b673 100644 (file)
--- a/src/rgw/rgw_rest_client.h
+++ b/src/rgw/rgw_rest_client.h
@@ -24,7 +24,7 @@ protected:
   size_t max_response; /* we need this as we don't stream out response */
   bufferlist response;
 
-  virtual int handle_header(const std::string& name, const std::string& val);
+  virtual int handle_header(std::string_view name, std::string_view val);
   virtual int handle_headers(const std::map<std::string, std::string>& headers, int http_status) { return 0; }
   void get_params_str(std::map<std::string, std::string>& extra_args, std::string& dest);
 
@@ -126,7 +126,7 @@ private:
 protected:
   bufferlist outbl;
 
-  int handle_header(const std::string& name, const std::string& val) override;
+  int handle_header(std::string_view name, std::string_view val) override;
   int handle_headers(const std::map<std::string, std::string>& headers, int http_status) override;
 public:
   int send_data(void *ptr, size_t len, bool *pause) override;