diff options
| author | Theo de Raadt <deraadt@cvs.openbsd.org> | 2011-01-06 22:49:11 +0000 |
|---|---|---|
| committer | Theo de Raadt <deraadt@cvs.openbsd.org> | 2011-01-06 22:49:11 +0000 |
| commit | 722d78ebbd2b0a01d95ed73cb7fea8b5457151af (patch) | |
| tree | b6eb719d1e2c4e414d8eed2a38cfbf7b19410c5d /sys/dev/rnd.c | |
| parent | 3545be19d5dda71a47303dae64295b3678115128 (diff) | |
For very large operations in randomread(), use a local rc4 instance
much like arc4random_buf_large does, but without re-initializing it
every 8K.
ok tedu
Diffstat (limited to 'sys/dev/rnd.c')
| -rw-r--r-- | sys/dev/rnd.c | 28 |
1 files changed, 22 insertions, 6 deletions
diff --git a/sys/dev/rnd.c b/sys/dev/rnd.c index 5bd85e00794..4cb9856feb9 100644 --- a/sys/dev/rnd.c +++ b/sys/dev/rnd.c @@ -1,4 +1,4 @@ -/* $OpenBSD: rnd.c,v 1.123 2011/01/06 15:41:50 deraadt Exp $ */ +/* $OpenBSD: rnd.c,v 1.124 2011/01/06 22:49:10 deraadt Exp $ */ /* * Copyright (c) 1996, 1997, 2000-2002 Michael Shalayeff. @@ -837,18 +837,34 @@ randomclose(dev_t dev, int flag, int mode, struct proc *p) int randomread(dev_t dev, struct uio *uio, int ioflag) { - int ret = 0; - u_int32_t *buf; + u_char lbuf[ARC4_SUB_KEY_BYTES]; + struct rc4_ctx lctx; + size_t total = uio->uio_resid; + u_char *buf; + int myctx = 0, ret = 0; if (uio->uio_resid == 0) return 0; - buf = malloc(POOLBYTES, M_TEMP, M_WAITOK); + buf = malloc(2 * PAGE_SIZE, M_TEMP, M_WAITOK); + if (total > ARC4_MAIN_MAX_BYTES) { + mtx_enter(&rndlock); + rc4_getbytes(&arc4random_state, lbuf, sizeof(lbuf)); + rndstats.arc4_reads += sizeof(lbuf); + mtx_leave(&rndlock); + + rc4_keysetup(&lctx, lbuf, sizeof(lbuf)); + rc4_skip(&lctx, 256 * 4); + myctx = 1; + } while (ret == 0 && uio->uio_resid > 0) { - int n = min(POOLBYTES, uio->uio_resid); + int n = min(2 * PAGE_SIZE, uio->uio_resid); - arc4random_buf(buf, n); + if (myctx) + rc4_getbytes(&lctx, buf, n); + else + arc4random_buf(buf, n); ret = uiomove((caddr_t)buf, n, uio); if (ret == 0 && uio->uio_resid > 0) yield(); |