move chacha context and buffer out of bss and allow mmap to place them

wherever it decides it would like them. first step. ok deraadt dlg djm

diff --git a/lib/libc/crypt/arc4random.c b/lib/libc/crypt/arc4random.c
index ef2332c..57acc0d 100644 (file)
--- a/lib/libc/crypt/arc4random.c
+++ b/lib/libc/crypt/arc4random.c
@@ -1,4 +1,4 @@
-/*     $OpenBSD: arc4random.c,v 1.27 2014/05/04 20:40:08 deraadt Exp $ */
+/*     $OpenBSD: arc4random.c,v 1.28 2014/05/06 02:31:45 tedu Exp $    */
 
 /*
  * Copyright (c) 1996, David Mazieres <dm@uun.org>
@@ -31,6 +31,8 @@
 #include <sys/param.h>
 #include <sys/time.h>
 #include <sys/sysctl.h>
+#include <sys/mman.h>
+
 #include "thread_private.h"
 
 #define KEYSTREAM_ONLY
@@ -48,8 +50,8 @@
 #define RSBUFSZ        (16*BLOCKSZ)
 static int rs_initialized;
 static pid_t rs_stir_pid;
-static chacha_ctx rs;          /* chacha context for random keystream */
-static u_char rs_buf[RSBUFSZ]; /* keystream blocks */
+static chacha_ctx *rs;         /* chacha context for random keystream */
+static u_char *rs_buf;         /* keystream blocks */
 static size_t rs_have;         /* valid bytes at end of rs_buf */
 static size_t rs_count;                /* bytes till reseed */
 
@@ -60,8 +62,16 @@ _rs_init(u_char *buf, size_t n)
 {
        if (n < KEYSZ + IVSZ)
                return;
-       chacha_keysetup(&rs, buf, KEYSZ * 8, 0);
-       chacha_ivsetup(&rs, buf + KEYSZ);
+
+       if ((rs = mmap(NULL, sizeof(*rs), PROT_READ|PROT_WRITE,
+           MAP_ANON, -1, 0)) == MAP_FAILED)
+               abort();
+       if ((rs_buf = mmap(NULL, RSBUFSZ, PROT_READ|PROT_WRITE,
+           MAP_ANON, -1, 0)) == MAP_FAILED)
+               abort();
+
+       chacha_keysetup(rs, buf, KEYSZ * 8, 0);
+       chacha_ivsetup(rs, buf + KEYSZ);
 }
 
 static void
@@ -110,7 +120,7 @@ _rs_rekey(u_char *dat, size_t datlen)
        memset(rs_buf, 0,RSBUFSZ);
 #endif
        /* fill rs_buf with the keystream */
-       chacha_encrypt_bytes(&rs, rs_buf, rs_buf, RSBUFSZ);
+       chacha_encrypt_bytes(rs, rs_buf, rs_buf, RSBUFSZ);
        /* mix in optional user provided data */
        if (dat) {
                size_t i, m;