GitHub CI: update list of container images

[tinc] / src / xalloc.h

diff --git a/src/xalloc.h b/src/xalloc.h
index 397f7b0..2b217e8 100644 (file)
--- a/src/xalloc.h
+++ b/src/xalloc.h
@@ -1,5 +1,8 @@
+#ifndef TINC_XALLOC_H
+#define TINC_XALLOC_H
+
 /*
-   xalloc.h -- malloc and related fuctions with out of memory checking
+   xalloc.h -- malloc and related functions with out of memory checking
    Copyright (C) 1990, 91, 92, 93, 94, 95, 96, 97 Free Software Foundation, Inc.
    Copyright (C) 2011-2013 Guus Sliepen <guus@tinc-vpn.org>
 
@@ -15,46 +18,79 @@
 
    You should have received a copy of the GNU General Public License along
    with this program; if not, write to the Free Software Foundation, Inc., Foundation,
-   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.  */
+   51 Franklin Street, Fifth Floor, Boston, MA 02110-1301 USA.
+*/
+
+#include "system.h"
 
-#ifndef __TINC_XALLOC_H__
-#define __TINC_XALLOC_H__
+#include <assert.h>
 
+static inline void *xmalloc(size_t n) ATTR_MALLOC;
 static inline void *xmalloc(size_t n) {
        void *p = malloc(n);
-       if(!p)
+
+       if(!p) {
                abort();
+       }
+
        return p;
 }
 
+static inline void *xzalloc(size_t n) ATTR_MALLOC;
 static inline void *xzalloc(size_t n) {
        void *p = calloc(1, n);
-       if(!p)
+
+       if(!p) {
                abort();
+       }
+
        return p;
 }
 
 static inline void *xrealloc(void *p, size_t n) {
        p = realloc(p, n);
-       if(!p)
+
+       if(!p) {
                abort();
+       }
+
        return p;
 }
 
+static inline char *xstrdup(const char *s) ATTR_MALLOC ATTR_NONNULL;
 static inline char *xstrdup(const char *s) {
        char *p = strdup(s);
-       if(!p)
+
+       if(!p) {
                abort();
+       }
+
        return p;
 }
 
+static inline int xvasprintf(char **strp, const char *fmt, va_list ap) ATTR_FORMAT(printf, 2, 0);
 static inline int xvasprintf(char **strp, const char *fmt, va_list ap) {
+#ifdef HAVE_WINDOWS
+       char buf[1024];
+       int result = vsnprintf(buf, sizeof(buf), fmt, ap);
+
+       if(result < 0) {
+               abort();
+       }
+
+       *strp = xstrdup(buf);
+#else
        int result = vasprintf(strp, fmt, ap);
-       if(result < 0)
+
+       if(result < 0) {
                abort();
+       }
+
+#endif
        return result;
 }
 
+static inline int xasprintf(char **strp, const char *fmt, ...) ATTR_FORMAT(printf, 2, 3);
 static inline int xasprintf(char **strp, const char *fmt, ...) {
        va_list ap;
        va_start(ap, fmt);
@@ -63,4 +99,51 @@ static inline int xasprintf(char **strp, const char *fmt, ...) {
        return result;
 }
 
+// Zero out a block of memory containing sensitive information using whatever secure
+// erase function is available on the platform (or an unreliable fallback if none are).
+// The pointer must not be NULL. Length can be zero, in which case the call is a noop.
+static inline void memzero(void *buf, size_t buflen) ATTR_NONNULL;
+static inline void memzero(void *buf, size_t buflen) {
+       assert(buf);
+
+       if(!buflen) {
+               return;
+       }
+
+#if defined(HAVE_EXPLICIT_BZERO)
+       explicit_bzero(buf, buflen);
+#elif defined(HAVE_EXPLICIT_MEMSET)
+       explicit_memset(buf, 0, buflen);
+#elif defined(HAVE_MEMSET_S)
+       errno_t err = memset_s(buf, buflen, 0, buflen);
+       assert(err == 0);
+#elif defined(HAVE_WINDOWS)
+       SecureZeroMemory(buf, buflen);
+#else
+       volatile uint8_t *p = buf;
+
+       while(buflen--) {
+               *p++ = 0;
+       }
+
 #endif
+}
+
+// Zero out a buffer of size `len` located at `ptr` and free() it.
+// Does nothing if called on NULL.
+static inline void xzfree(void *ptr, size_t len) {
+       if(ptr) {
+               memzero(ptr, len);
+               free(ptr);
+       }
+}
+
+// Zero out a NULL-terminated string using memzero() and then free it.
+// Does nothing if called on NULL.
+static inline void free_string(char *str) {
+       if(str) {
+               xzfree(str, strlen(str));
+       }
+}
+
+#endif // TINC_XALLOC_H