Avoid caches to get the most recent copy of the key. This is bug

#1061

keyserver/ChangeLog

@@ -1,3 +1,13 @@
+2009-05-26  David Shaw  <dshaw@jabberwocky.com>
+
+	* curl-shim.c (curl_slist_append, curl_slist_free_all): New.
+	Simple wrappers around STRLIST to emulate the curl way of doing
+	string lists.
+	(curl_easy_setopt): Handle the curl HTTPHEADER option.
+
+	* gpgkeys_curl.c, gpgkeys_hkp.c (main): Avoid caches to get the
+	most recent copy of the key.  This is bug #1061.
+
 2009-05-03  David Shaw  <dshaw@jabberwocky.com>
 
 	* gpgkeys_mailto.in: Set 'mail-from' as a keyserver-option, rather

keyserver/curl-shim.c

@@ -146,6 +146,9 @@ curl_easy_setopt(CURL *curl,CURLoption option,...)
     case CURLOPT_STDERR:
       curl->errors=va_arg(ap,FILE *);
       break;
+    case CURLOPT_HTTPHEADER:
+      curl->headers=va_arg(ap,struct curl_slist *);
+      break;
     default:
       /* We ignore the huge majority of curl options */
       break;
@@ -186,7 +189,7 @@ curl_easy_perform(CURL *curl)
   if(curl->flags.post)
     {
       rc=http_open(&curl->hd,HTTP_REQ_POST,curl->url,curl->auth,0,proxy,
-		   curl->srvtag);
+		   curl->srvtag,curl->headers?curl->headers->list:NULL);
       if(rc==0)
 	{
 	  char content_len[50];
@@ -208,7 +211,7 @@ curl_easy_perform(CURL *curl)
   else
     {
       rc=http_open(&curl->hd,HTTP_REQ_GET,curl->url,curl->auth,0,proxy,
-		   curl->srvtag);
+		   curl->srvtag,curl->headers?curl->headers->list:NULL);
       if(rc==0)
 	{
 	  rc=http_wait_response(&curl->hd,&curl->status);
@@ -335,3 +338,28 @@ curl_version_info(int type)
 
   return &data;
 }
+
+struct curl_slist *
+curl_slist_append(struct curl_slist *list,const char *string)
+{
+  if(!list)
+    {
+      list=calloc(1,sizeof(*list));
+      if(!list)
+	return NULL;
+    }
+
+  add_to_strlist(&list->list,string);
+
+  return list;
+}
+
+void
+curl_slist_free_all(struct curl_slist *list)
+{
+  if(list)
+    {
+      free_strlist(list->list);
+      free(list);
+    }
+}

keyserver/curl-shim.h

@@ -49,6 +49,7 @@ typedef enum
     CURLOPT_POST,
     CURLOPT_POSTFIELDS,
     CURLOPT_FAILONERROR,
+    CURLOPT_HTTPHEADER,
     CURLOPT_SRVTAG_GPG_HACK
   } CURLoption;
 
@@ -67,6 +68,7 @@ typedef struct
   char *srvtag;
   unsigned int status;
   FILE *errors;
+  struct curl_slist *headers;
   struct
   {
     unsigned int post:1;
@@ -96,4 +98,13 @@ char *curl_easy_escape(CURL *curl,char *str,int len);
 #define curl_version() "GnuPG curl-shim"
 curl_version_info_data *curl_version_info(int type);
 
+struct curl_slist
+{
+  STRLIST list;
+};
+
+struct curl_slist *curl_slist_append(struct curl_slist *list,
+				     const char *string);
+void curl_slist_free_all(struct curl_slist *list);
+
 #endif /* !_CURL_SHIM_H_ */

keyserver/gpgkeys_curl.c

@@ -118,6 +118,7 @@ main(int argc,char *argv[])
   long follow_redirects=5;
   char *proxy=NULL;
   curl_version_info_data *curldata;
+  struct curl_slist *headers=NULL;
 
   console=stderr;
 
@@ -306,6 +307,26 @@ main(int argc,char *argv[])
   curl_easy_setopt(curl,CURLOPT_SSL_VERIFYPEER,(long)opt->flags.check_cert);
   curl_easy_setopt(curl,CURLOPT_CAINFO,opt->ca_cert_file);
 
+  /* Avoid caches to get the most recent copy of the key.  This is bug
+     #1061.  In pre-curl versions of the code, we didn't do it.  Then
+     we did do it (as a curl default) until curl changed the default.
+     Now we're doing it again, but in such a way that changing
+     defaults in the future won't impact us.  We set both the Pragma
+     and Cache-Control versions of the header, so we're good with both
+     HTTP 1.0 and 1.1. */
+  headers=curl_slist_append(headers,"Pragma: no-cache");
+  if(headers)
+    headers=curl_slist_append(headers,"Cache-Control: no-cache");
+
+  if(!headers)
+    {
+      fprintf(console,"gpgkeys: out of memory when building HTTP headers\n");
+      ret=KEYSERVER_NO_MEMORY;
+      goto fail;
+    }
+
+  curl_easy_setopt(curl,CURLOPT_HTTPHEADER,headers);
+
   if(proxy)
     curl_easy_setopt(curl,CURLOPT_PROXY,proxy);
 
@@ -386,6 +407,8 @@ main(int argc,char *argv[])
 
   free_ks_options(opt);
 
+  curl_slist_free_all(headers);
+
   if(curl)
     curl_easy_cleanup(curl);
 

keyserver/gpgkeys_hkp.c

@@ -550,6 +550,7 @@ main(int argc,char *argv[])
   int failed=0;
   struct keylist *keylist=NULL,*keyptr=NULL;
   char *proxy=NULL;
+  struct curl_slist *headers=NULL;
 
   console=stderr;
 
@@ -746,6 +747,26 @@ main(int argc,char *argv[])
   curl_easy_setopt(curl,CURLOPT_SSL_VERIFYPEER,(long)opt->flags.check_cert);
   curl_easy_setopt(curl,CURLOPT_CAINFO,opt->ca_cert_file);
 
+  /* Avoid caches to get the most recent copy of the key.  This is bug
+     #1061.  In pre-curl versions of the code, we didn't do it.  Then
+     we did do it (as a curl default) until curl changed the default.
+     Now we're doing it again, but in such a way that changing
+     defaults in the future won't impact us.  We set both the Pragma
+     and Cache-Control versions of the header, so we're good with both
+     HTTP 1.0 and 1.1. */
+  headers=curl_slist_append(headers,"Pragma: no-cache");
+  if(headers)
+    headers=curl_slist_append(headers,"Cache-Control: no-cache");
+
+  if(!headers)
+    {
+      fprintf(console,"gpgkeys: out of memory when building HTTP headers\n");
+      ret=KEYSERVER_NO_MEMORY;
+      goto fail;
+    }
+
+  curl_easy_setopt(curl,CURLOPT_HTTPHEADER,headers);
+
   if(proxy)
     curl_easy_setopt(curl,CURLOPT_PROXY,proxy);
 
@@ -923,6 +944,8 @@ main(int argc,char *argv[])
 
   free_ks_options(opt);
 
+  curl_slist_free_all(headers);
+
   if(curl)
     curl_easy_cleanup(curl);