hsts: enable by default

No longer considered experimental.

Closes #6700

15 files changed, 65 insertions, 40 deletions

diff --git a/CMakeLists.txt b/CMakeLists.txt
index 3a20028ba..02474e29c 100644
--- a/CMakeLists.txt
+++ b/CMakeLists.txt
@@ -210,6 +210,8 @@ endif()
 
 option(CURL_DISABLE_ALTSVC "to disable alt-svc support" OFF)
 mark_as_advanced(CURL_DISABLE_ALTSVC)
+option(CURL_DISABLE_HSTS "to disable HSTS support" OFF)
+mark_as_advanced(CURL_DISABLE_HSTS)
 option(CURL_DISABLE_COOKIES "to disable cookies support" OFF)
 mark_as_advanced(CURL_DISABLE_COOKIES)
 option(CURL_DISABLE_CRYPTO_AUTH "to disable cryptographic authentication" OFF)
@@ -1371,6 +1373,7 @@ _add_if("Largefile"     (SIZEOF_CURL_OFF_T GREATER 4) AND
 _add_if("SSPI"          USE_WINDOWS_SSPI)
 _add_if("GSS-API"       HAVE_GSSAPI)
 _add_if("alt-svc"       NOT CURL_DISABLE_ALTSVC)
+_add_if("HSTS"          NOT CURL_DISABLE_HSTS)
 # TODO SSP1 missing for SPNEGO
 _add_if("SPNEGO"        NOT CURL_DISABLE_CRYPTO_AUTH AND
                         (HAVE_GSSAPI OR USE_WINDOWS_SSPI))
diff --git a/configure.ac b/configure.ac
index 2a00aea2b..5da2ac37c 100755
--- a/configure.ac
+++ b/configure.ac
@@ -165,13 +165,15 @@ curl_verbose_msg="enabled (--disable-verbose)"
    curl_rtmp_msg="no      (--with-librtmp)"
   curl_mtlnk_msg="no      (--with-libmetalink)"
     curl_psl_msg="no      (--with-libpsl)"
- curl_altsvc_msg="enabled";
+ curl_altsvc_msg="enabled (--disable-alt-svc)"
+   curl_hsts_msg="enabled (--disable-hsts)"
     ssl_backends=
      curl_h1_msg="enabled (internal)"
      curl_h2_msg="no      (--with-nghttp2, --with-hyper)"
      curl_h3_msg="no      (--with-ngtcp2, --with-quiche)"
 
 enable_altsvc="yes"
+enable_hsts="yes"
 
 dnl
 dnl Save some initial values the user might have provided
@@ -395,9 +397,12 @@ AS_HELP_STRING([--disable-http],[Disable HTTP support]),
        AC_SUBST(CURL_DISABLE_RTSP, [1])
        dnl toggle off alt-svc too when HTTP is disabled
        AC_DEFINE(CURL_DISABLE_ALTSVC, 1, [disable alt-svc])
+       AC_DEFINE(CURL_DISABLE_HSTS, 1, [disable HSTS])
        curl_h1_msg="no      (--enable-http, --with-hyper)"
        curl_altsvc_msg="no";
+       curl_hsts_msg="no      (--enable-hsts)";
        enable_altsvc="no"
+       enable_hsts="no"
        ;;
   *)   AC_MSG_RESULT(yes)
        ;;
@@ -5071,29 +5076,34 @@ AS_HELP_STRING([--disable-alt-svc],[Disable alt-svc support]),
        AC_MSG_RESULT(no)
 )
 
-dnl ************************************************************
-dnl switch on/off hsts
-dnl
-curl_hsts_msg="no      (--enable-hsts)";
-AC_MSG_CHECKING([whether to support HSTS])
-AC_ARG_ENABLE(hsts,
-AS_HELP_STRING([--enable-hsts],[Enable HSTS support])
-AS_HELP_STRING([--disable-hsts],[Disable HSTS support]),
-[ case "$enableval" in
-  no)
+dnl only check for HSTS if there's SSL present
+if test -n "$SSL_ENABLED"; then
+
+  dnl ************************************************************
+  dnl switch on/off hsts
+  dnl
+  AC_MSG_CHECKING([whether to support HSTS])
+  AC_ARG_ENABLE(hsts,
+  AS_HELP_STRING([--enable-hsts],[Enable HSTS support])
+  AS_HELP_STRING([--disable-hsts],[Disable HSTS support]),
+  [ case "$enableval" in
+    no)
        AC_MSG_RESULT(no)
+       enable_hsts="no"
        ;;
-  *) AC_MSG_RESULT(yes)
-       curl_hsts_msg="enabled";
-       enable_hsts="yes"
+    *) AC_MSG_RESULT(yes)
        ;;
-  esac ],
+    esac ],
        AC_MSG_RESULT(no)
-)
+  )
+else
+  AC_MSG_NOTICE([disables HSTS due to lack of SSL])
+  enable_hsts="no"
+fi
 
-if test "$enable_hsts" = "yes"; then
-  AC_DEFINE(USE_HSTS, 1, [to enable HSTS])
-  experimental="$experimental HSTS"
+if test "x$enable_hsts" != "xyes"; then
+  curl_hsts_msg="no      (--enable-hsts)";
+  AC_DEFINE(CURL_DISABLE_HSTS, 1, [disable alt-svc])
 fi
 
 dnl *************************************************************
@@ -5480,6 +5490,7 @@ AC_MSG_NOTICE([Configured to build curl/libcurl:
   Metalink:         ${curl_mtlnk_msg}
   PSL:              ${curl_psl_msg}
   Alt-svc:          ${curl_altsvc_msg}
+  HSTS:             ${curl_hsts_msg}
   HTTP1:            ${curl_h1_msg}
   HTTP2:            ${curl_h2_msg}
   HTTP3:            ${curl_h3_msg}
diff --git a/docs/CURL-DISABLE.md b/docs/CURL-DISABLE.md
index 6f703a3d9..3aa9608f8 100644
--- a/docs/CURL-DISABLE.md
+++ b/docs/CURL-DISABLE.md
@@ -37,6 +37,10 @@ about existing options to `curl_easy_setopt`.
 
 Disable the GOPHER protocol.
 
+## CURL_DISABLE_HSTS
+
+Disable the HTTP Strict Transport Security support.
+
 ## CURL_DISABLE_HTTP
 
 Disable the HTTP(S) protocols. Note that this then also disable HTTP proxy
diff --git a/docs/EXPERIMENTAL.md b/docs/EXPERIMENTAL.md
index 6a84f5e17..ce9a1b8e8 100644
--- a/docs/EXPERIMENTAL.md
+++ b/docs/EXPERIMENTAL.md
@@ -21,4 +21,3 @@ Experimental support in curl means:
  - The Hyper HTTP backend
  - HTTP/3 support and options
  - CURLSSLOPT_NATIVE_CA (No configure option, feature built in when supported)
- - HSTS support and options
diff --git a/lib/curl_get_line.c b/lib/curl_get_line.c
index 438ede704..8f3b0bd8c 100644
--- a/lib/curl_get_line.c
+++ b/lib/curl_get_line.c
@@ -5,7 +5,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 1998 - 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 1998 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -23,7 +23,7 @@
 #include "curl_setup.h"
 
 #if !defined(CURL_DISABLE_COOKIES) || !defined(CURL_DISABLE_ALTSVC) ||  \
-  defined(USE_HSTS)
+  !defined(CURL_DISABLE_HSTS)
 
 #include "curl_get_line.h"
 #include "curl_memory.h"
diff --git a/lib/easy.c b/lib/easy.c
index 4ce1bbf63..460668191 100644
--- a/lib/easy.c
+++ b/lib/easy.c
@@ -895,7 +895,7 @@ struct Curl_easy *curl_easy_duphandle(struct Curl_easy *data)
       (void)Curl_altsvc_load(outcurl->asi, outcurl->set.str[STRING_ALTSVC]);
   }
 #endif
-#ifdef USE_HSTS
+#ifndef CURL_DISABLE_HSTS
   if(data->hsts) {
     outcurl->hsts = Curl_hsts_init();
     if(!outcurl->hsts)
diff --git a/lib/hsts.c b/lib/hsts.c
index fd4926f36..ef166f196 100644
--- a/lib/hsts.c
+++ b/lib/hsts.c
@@ -25,7 +25,7 @@
  */
 #include "curl_setup.h"
 
-#if !defined(CURL_DISABLE_HTTP) && defined(USE_HSTS)
+#if !defined(CURL_DISABLE_HTTP) && !defined(CURL_DISABLE_HSTS)
 #include <curl/curl.h>
 #include "urldata.h"
 #include "llist.h"
@@ -37,6 +37,7 @@
 #include "parsedate.h"
 #include "rand.h"
 #include "rename.h"
+#include "strtoofft.h"
 
 /* The last 3 #include files should be in this order */
 #include "curl_printf.h"
@@ -58,7 +59,10 @@ static time_t debugtime(void *unused)
   char *timestr = getenv("CURL_TIME");
   (void)unused;
   if(timestr) {
-    unsigned long val = strtol(timestr, NULL, 10) + deltatime;
+    curl_off_t val;
+    (void)curlx_strtoofft(timestr, NULL, 10, &val);
+
+    val += (curl_off_t)deltatime;
     return (time_t)val;
   }
   return time(NULL);
@@ -274,7 +278,7 @@ static CURLcode hsts_push(struct Curl_easy *data,
   e.namelen = strlen(sts->host);
   e.includeSubDomains = sts->includeSubDomains;
 
-  result = Curl_gmtime(sts->expires, &stamp);
+  result = Curl_gmtime((time_t)sts->expires, &stamp);
   if(result)
     return result;
 
@@ -294,7 +298,7 @@ static CURLcode hsts_push(struct Curl_easy *data,
 static CURLcode hsts_out(struct stsentry *sts, FILE *fp)
 {
   struct tm stamp;
-  CURLcode result = Curl_gmtime(sts->expires, &stamp);
+  CURLcode result = Curl_gmtime((time_t)sts->expires, &stamp);
   if(result)
     return result;
 
@@ -439,7 +443,10 @@ static CURLcode hsts_pull(struct Curl_easy *data, struct hsts *h)
           expires = Curl_getdate_capped(e.expire);
         else
           expires = TIME_T_MAX; /* the end of time */
-        result = hsts_create(h, e.name, e.includeSubDomains, expires);
+        result = hsts_create(h, e.name,
+                             /* bitfield to bool conversion: */
+                             e.includeSubDomains ? TRUE : FALSE,
+                             expires);
         if(result)
           return result;
       }
@@ -517,4 +524,4 @@ CURLcode Curl_hsts_loadcb(struct Curl_easy *data, struct hsts *h)
   return hsts_pull(data, h);
 }
 
-#endif /* CURL_DISABLE_HTTP || USE_HSTS */
+#endif /* CURL_DISABLE_HTTP || CURL_DISABLE_HSTS */
diff --git a/lib/hsts.h b/lib/hsts.h
index ae5db74a2..baa582864 100644
--- a/lib/hsts.h
+++ b/lib/hsts.h
@@ -7,7 +7,7 @@
  *                            | (__| |_| |  _ <| |___
  *                             \___|\___/|_| \_\_____|
  *
- * Copyright (C) 2020, Daniel Stenberg, <daniel@haxx.se>, et al.
+ * Copyright (C) 2020 - 2021, Daniel Stenberg, <daniel@haxx.se>, et al.
  *
  * This software is licensed as described in the file COPYING, which
  * you should have received as part of this distribution. The terms
@@ -23,7 +23,7 @@
  ***************************************************************************/
 #include "curl_setup.h"
 
-#if !defined(CURL_DISABLE_HTTP) && defined(USE_HSTS)
+#if !defined(CURL_DISABLE_HTTP) && !defined(CURL_DISABLE_HSTS)
 #include <curl/curl.h>
 #include "llist.h"
 
@@ -35,7 +35,7 @@ struct stsentry {
   struct Curl_llist_element node;
   const char *host;
   bool includeSubDomains;
-  time_t expires; /* the timestamp of this entry's expiry */
+  curl_off_t expires; /* the timestamp of this entry's expiry */
 };
 
 /* The HSTS cache. Needs to be able to tailmatch host names. */
@@ -61,5 +61,5 @@ CURLcode Curl_hsts_loadcb(struct Curl_easy *data,
 #define Curl_hsts_cleanup(x)
 #define Curl_hsts_loadcb(x,y)
 #define Curl_hsts_save(x,y,z)
-#endif /* CURL_DISABLE_HTTP || USE_HSTS */
+#endif /* CURL_DISABLE_HTTP || CURL_DISABLE_HSTS */
 #endif /* HEADER_CURL_HSTS_H */
diff --git a/lib/http.c b/lib/http.c
index 02c81c419..3cb21760d 100644
--- a/lib/http.c
+++ b/lib/http.c
@@ -3618,7 +3618,7 @@ CURLcode Curl_http_header(struct Curl_easy *data, struct connectdata *conn,
     }
   }
 
-#ifdef USE_HSTS
+#ifndef CURL_DISABLE_HSTS
   /* If enabled, the header is incoming and this is over HTTPS */
   else if(data->hsts && checkprefix("Strict-Transport-Security:", headp) &&
           (conn->handler->flags & PROTOPT_SSL)) {
diff --git a/lib/setopt.c b/lib/setopt.c
index 53b30da35..55360cba1 100644
--- a/lib/setopt.c
+++ b/lib/setopt.c
@@ -2911,7 +2911,7 @@ CURLcode Curl_vsetopt(struct Curl_easy *data, CURLoption option, va_list param)
     data->set.trailer_data = va_arg(param, void *);
 #endif
     break;
-#ifdef USE_HSTS
+#ifndef CURL_DISABLE_HSTS
   case CURLOPT_HSTSREADFUNCTION:
     data->set.hsts_read = va_arg(param, curl_hstsread_callback);
     break;
diff --git a/lib/url.c b/lib/url.c
index 19fcfb842..949e380aa 100644
--- a/lib/url.c
+++ b/lib/url.c
@@ -1944,7 +1944,7 @@ static CURLcode parseurlandfillconn(struct Curl_easy *data,
       return CURLE_OUT_OF_MEMORY;
   }
 
-#ifdef USE_HSTS
+#ifndef CURL_DISABLE_HSTS
   if(data->hsts && strcasecompare("http", data->state.up.scheme)) {
     if(Curl_hsts(data->hsts, data->state.up.hostname, TRUE)) {
       char *url;
diff --git a/lib/urldata.h b/lib/urldata.h
index fec875652..b7b17e30c 100644
--- a/lib/urldata.h
+++ b/lib/urldata.h
@@ -1664,7 +1664,7 @@ struct UserDefined {
   curl_conv_callback convtonetwork;
   /* function to convert from UTF-8 encoding: */
   curl_conv_callback convfromutf8;
-#ifdef USE_HSTS
+#ifndef CURL_DISABLE_HSTS
   curl_hstsread_callback hsts_read;
   void *hsts_read_userp;
   curl_hstswrite_callback hsts_write;
@@ -1926,7 +1926,7 @@ struct Curl_easy {
                                   NOTE that the 'cookie' field in the
                                   UserDefined struct defines if the "engine"
                                   is to be used or not. */
-#ifdef USE_HSTS
+#ifndef CURL_DISABLE_HSTS
   struct hsts *hsts;
 #endif
 #ifndef CURL_DISABLE_ALTSVC
diff --git a/lib/version.c b/lib/version.c
index b33f2fe83..d2c86baac 100644
--- a/lib/version.c
+++ b/lib/version.c
@@ -436,7 +436,7 @@ static curl_version_info_data version_info = {
 #ifndef CURL_DISABLE_ALTSVC
   | CURL_VERSION_ALTSVC
 #endif
-#if defined(USE_HSTS)
+#ifndef CURL_DISABLE_HSTS
   | CURL_VERSION_HSTS
 #endif
 #if defined(USE_GSASL)
diff --git a/tests/data/test493 b/tests/data/test493
index bb0b5dee7..1dd498f0d 100644
--- a/tests/data/test493
+++ b/tests/data/test493
@@ -27,6 +27,7 @@ http
 </server>
 <features>
 HSTS
+proxy
 </features>
 
 <file name="log/input%TESTNUMBER">
diff --git a/tests/unit/unit1660.c b/tests/unit/unit1660.c
index cc2451932..43efa24b3 100644
--- a/tests/unit/unit1660.c
+++ b/tests/unit/unit1660.c
@@ -36,7 +36,7 @@ unit_stop(void)
   curl_global_cleanup();
 }
 
-#if defined(CURL_DISABLE_HTTP) || !defined(USE_HSTS)
+#if defined(CURL_DISABLE_HTTP) || defined(CURL_DISABLE_HSTS)
 UNITTEST_START
 {
   return 0; /* nothing to do when HTTP or HSTS are disabled */