Merge pull request #80 from pprindeville/reorg-magic

Reorg magic
kravietz · Dec 21, 2016 · 773a1ca · 773a1ca
2 parents 0a3234c + 6fac250
commit 773a1ca
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Showing 4 changed files with 65 additions and 41 deletions.
diff --git a/libtac/lib/header.c b/libtac/lib/header.c
@@ -26,17 +26,7 @@
   #include "config.h"
 #endif
 
-#if defined(HAVE_OPENSSL_RAND_H) && defined(HAVE_LIBCRYPTO)
-# include <openssl/rand.h>
-#elif defined(HAVE_GETRANDOM)
-# if defined(HAVE_LINUX_RANDOM_H)
-#  include <linux/random.h>
-# elif defined(HAVE_SYS_RANDOM_H)
-#  include <sys/random.h>
-# endif
-#else
-# include "magic.h"
-#endif
+#include "magic.h"
 
 /* Miscellaneous variables that are global, because we need
  * store their values between different functions and connections.
@@ -88,16 +78,7 @@ HDR *_tac_req_header(u_char type, int cont_session) {
 
     /* make session_id from pseudo-random number */
     if (!cont_session) {
-#if defined(HAVE_OPENSSL_RAND_H) && defined(HAVE_LIBCRYPTO)
-    	// the preferred way is to use OpenSSL abstraction as we are linking it anyway for MD5
-        RAND_pseudo_bytes((unsigned char *) &session_id, sizeof(session_id));
-#elif defined(HAVE_GETRANDOM)
-        // experimental
-        getrandom((void *) &session_id, sizeof(session_id), GRND_NONBLOCK);
-#else
-        // if everything fails use the legacy code
         session_id = magic();
-#endif
     }
     th->session_id = htonl(session_id);
 

diff --git a/libtac/lib/magic.c b/libtac/lib/magic.c
@@ -18,13 +18,6 @@
  * See `CHANGES' file for revision history.
  */
 
-#ifdef HAVE_CONFIG_H
-  #include "config.h"
-#endif
-
-/* if OpenSSL library is available this legacy code will not be compiled in */
-#if !defined(HAVE_OPENSSL_RAND_H) && !defined(HAVE_LIBCRYPTO)
-
 #include <stdio.h>
 #include <stdlib.h>
 #include <sys/types.h>
@@ -33,25 +26,81 @@
 #include <sys/stat.h>
 #include <fcntl.h>
 
+#ifdef HAVE_CONFIG_H
+  #include "config.h"
+#endif
+
 #include "magic.h"
 
-static int magic_initialised = 0;
+#ifdef _MSC_VER
+# pragma section(".CRT$XCU",read)
+# define INITIALIZER2_(f,p) \
+	static void f(void); \
+	__declspec(allocate(".CRT$XCU")) void (*f##_)(void) = f; \
+	__pragma(comment(linker,"/include:" p #f "_")) \
+	static void f(void)
+# ifdef _WIN64
+#  define INITIALIZER(f) INITIALIZER2_(f,"")
+# else
+#  define INITIALIZER(f) INITIALIZER2_(f,"_")
+# endif
+#else /* __GNUC__ */
+# define INITIALIZER(f) \
+	static void f(void) __attribute__((constructor)); \
+	static void f(void)
+#endif
+
+/* if OpenSSL library is available this legacy code will not be compiled in */
+#if defined(HAVE_OPENSSL_RAND_H) && defined(HAVE_LIBCRYPTO)
+
+#include <openssl/rand.h>
+
+/*
+ * magic - Returns the next magic number.
+ */
+u_int32_t
+magic()
+{
+    u_int32_t num;
+
+    RAND_pseudo_bytes((unsigned char *)&num, sizeof(num));
+
+    return num;
+}
+
+#elif defined(HAVE_GETRANDOM)
+
+# if defined(HAVE_LINUX_RANDOM_H)
+#  include <linux/random.h>
+# elif defined(HAVE_SYS_RANDOM_H)
+#  include <sys/random.h>
+# endif
+
+/*
+ * magic - Returns the next magic number.
+ */
+u_int32_t
+magic()
+{
+    u_int32_t num;
+
+    getrandom(&num, sizeof(num), GRND_NONBLOCK);
+    return num;
+}
+
+#else
 
 /*
  * magic_init - Initialize the magic number generator.
  *
  * Attempts to compute a random number seed which will not repeat.
  */
-void
-magic_init()
+INITIALIZER(magic_init)
 {
     struct stat statbuf;
     long seed = 0;
     struct timeval t;
 
-    if (magic_initialised)
-        return;
-
     // try to initialise seed from urandom
     if (!lstat("/dev/urandom", &statbuf) && S_ISCHR(statbuf.st_mode)) {
         int rfd = open("/dev/urandom", O_RDONLY);
@@ -67,21 +116,16 @@ magic_init()
 
     // finally seed the PRNG
     srandom(seed);
-    magic_initialised = 1;
 }
 
-#include <pthread.h>
 /*
  * magic - Returns the next magic number.
  */
 u_int32_t
 magic()
 {
-    static pthread_once_t magic_control = PTHREAD_ONCE_INIT;
-
-    pthread_once(&magic_control, &magic_init);
-
     return (u_int32_t)random();
 }
 
 #endif
+
diff --git a/libtac/lib/magic.h b/libtac/lib/magic.h
@@ -24,7 +24,6 @@
 #include "libtac.h"
 
 __BEGIN_DECLS
-void magic_init __P((void));	/* Initialize the magic number generator */
 u_int32_t magic __P((void));	/* Returns the next magic number */
 __END_DECLS
 

diff --git a/libtac/lib/md5.c b/libtac/lib/md5.c
@@ -23,7 +23,7 @@
 #endif
 
 /* if OpenSSL library is available this legacy code will not be compiled in */
-#if !defined(HAVE_OPENSSL_MD5_H) && !defined(HAVE_LIBCRYPTO)
+#if !(defined(HAVE_OPENSSL_MD5_H) && defined(HAVE_LIBCRYPTO))
 
 #include <string.h>
 #include "md5.h"