ref: 2edce3dfbe6424e1db0707f0bdb4f8a8f540f194
parent: 8e3ca2b766e47e3e72587ade1767a565591cf7d2
author: 9ferno <gophone2015@gmail.com>
date: Wed Oct 20 16:11:43 EDT 2021
import 9front 9/port/random.c
--- a/include/kern.h
+++ b/include/kern.h
@@ -578,8 +578,8 @@
extern int wstat(char*, char*);
extern ulong rendezvous(ulong, ulong);
-extern u32 getpid(void);
-extern u32 getppid(void);
+extern s32 getpid(void);
+extern s32 getppid(void);
extern void rerrstr(char*, uint);
extern char* sysname(void);
extern void werrstr(char*, ...);
--- a/os/port/portdat.h
+++ b/os/port/portdat.h
@@ -505,6 +505,8 @@
u32 alarm; /* Time of call */
s32 pri; /* scheduler priority */
u32 twhen;
+
+ Timer; /* For tsleep and real-time */
Rendez* trend;
Proc* tlink;
s32 (*tfn)(void*);
--- a/os/port/random.c
+++ b/os/port/random.c
@@ -3,7 +3,10 @@
#include "mem.h"
#include "dat.h"
#include "fns.h"
+#include "../port/error.h"
+#include <libsec.h>
+
/* machine specific hardware random number generator */
void (*hwrandbuf)(void*, u32) = nil;
@@ -10,150 +13,158 @@
static struct
{QLock;
- Rendez producer;
- Rendez consumer;
- ulong randomcount;
- uchar buf[1024];
- uchar *ep;
- uchar *rp;
- uchar *wp;
- uchar next;
- uchar bits;
- uchar wakeme;
- uchar filled;
- int target;
- int kprocstarted;
- ulong randn;
-} rb;
+ Chachastate;
+} *rs;
-static int
-rbnotfull(void*)
+typedef struct Seedbuf Seedbuf;
+struct Seedbuf
{- int i;
+ ulong randomcount;
+ uchar buf[64];
+ uchar nbuf;
+ uchar next;
+ ushort bits;
- i = rb.wp - rb.rp;
- if(i < 0)
- i += sizeof(rb.buf);
- return i < rb.target;
-}
+ SHA2_512state ds;
+};
-static int
-rbnotempty(void*)
-{- return rb.wp != rb.rp;
-}
-
static void
-genrandom(void*)
+randomsample(Ureg*, Timer *t)
{- setpri(PriBackground);
+ Seedbuf *s = t->ta;
- for(;;) {- for(;;)
- if(++rb.randomcount > 100000)
- break;
- if(anyhigher())
- sched();
- if(rb.filled || !rbnotfull(0))
- sleep(&rb.producer, rbnotfull, 0);
- }
+ if(s->randomcount == 0 || s->nbuf >= sizeof(s->buf))
+ return;
+ s->bits = (s->bits<<2) ^ s->randomcount;
+ s->randomcount = 0;
+ if(++s->next < 8/2)
+ return;
+ s->next = 0;
+ s->buf[s->nbuf++] ^= s->bits;
}
/*
- * produce random bits in a circular buffer
- */
+12:57 < joe7> In os/port/random.c:^randomseed() function, the up variable is used.
+ From the timeradd() definition, it should be a Timer * variable.
+12:57 < joe7> But, I cannot find the definition of that variable in random.c
+12:58 < cinap_lenrek> joe7: the Proc structure has a timer built in
+12:58 < cinap_lenrek> joe7: anonymous struct
+12:58 < cinap_lenrek> the compiler figures out the offset within the struct
+12:59 < joe7> oh, it figures out the offset too? I was thinking that if the
+ fields should be at the beginning.
+12:59 < cinap_lenrek> nope
+12:59 < cinap_lenrek> can be anywhere
+12:59 < cinap_lenrek> welcome to plan9 c
+12:59 < joe7> I could not figure out how it could do the translation from Proc * to Timer *
+13:00 < joe7> thanks.
+*/
static void
-randomclock(void)
+randomseed(void*)
{- uchar *p;
+ Seedbuf *s;
- if(rb.randomcount == 0)
- return;
+ /* TODO
+ * use the secret memory, used to back cryptographic
+ * keys and cipher states.
+ * Not sure if it is relevant to inferno
+ s = secalloc(sizeof(Seedbuf));
+ */
+ s = smalloc(sizeof(Seedbuf));
- if(!rbnotfull(0)) {- rb.filled = 1;
- return;
+ if(hwrandbuf != nil)
+ (*hwrandbuf)(s->buf, sizeof(s->buf));
+
+ /* Frequency close but not equal to HZ */
+ up->tns = (vlong)(MS2HZ+3)*1000000LL;
+ up->tmode = Tperiodic;
+ up->tt = nil;
+ up->ta = s;
+ up->tf = randomsample;
+ timeradd(up);
+ while(s->nbuf < sizeof(s->buf)){+ if(++s->randomcount <= 100000)
+ continue;
+ if(anyhigher())
+ sched();
}
+ timerdel(up);
- rb.bits = (rb.bits<<2) ^ (rb.randomcount&3);
- rb.randomcount = 0;
+ sha2_512(s->buf, sizeof(s->buf), s->buf, &s->ds);
+ setupChachastate(rs, s->buf, 32, s->buf+32, 12, 20);
+ qunlock(rs);
- rb.next += 2;
- if(rb.next != 8)
- return;
+ /* secfree(s); */
+ free(s);
- rb.next = 0;
- *rb.wp ^= rb.bits ^ *rb.rp;
- p = rb.wp+1;
- if(p == rb.ep)
- p = rb.buf;
- rb.wp = p;
-
- if(rb.wakeme)
- wakeup(&rb.consumer);
+ pexit("", 1);}
void
randominit(void)
{- /* Frequency close but not equal to HZ */
- addclock0link(randomclock, 13);
- rb.target = 16;
- rb.ep = rb.buf + sizeof(rb.buf);
- rb.rp = rb.wp = rb.buf;
+ /* rs = secalloc(sizeof(*rs)); */
+ rs = smalloc(sizeof(*rs));
+ qlock(rs); /* randomseed() unlocks once seeded */
+ kproc("randomseed", randomseed, nil, 0);}
-/*
- * consume random bytes from a circular buffer
- */
ulong
-randomread(void *xp, ulong n)
+randomread(void *p, ulong n)
{- int i, sofar;
- uchar *e, *p;
+ Chachastate c;
- p = xp;
+ if(n == 0)
+ return 0;
- qlock(&rb);
- if(waserror()){- qunlock(&rb);
- nexterror();
- }
- if(!rb.kprocstarted){- rb.kprocstarted = 1;
- kproc("genrand", genrandom, nil, 0);- }
+ if(hwrandbuf != nil)
+ (*hwrandbuf)(p, n);
- for(sofar = 0; sofar < n; sofar += i){- i = rb.wp - rb.rp;
- if(i == 0){- rb.wakeme = 1;
- wakeup(&rb.producer);
- sleep(&rb.consumer, rbnotempty, 0);
- rb.wakeme = 0;
- continue;
- }
- if(i < 0)
- i = rb.ep - rb.rp;
- if((i+sofar) > n)
- i = n - sofar;
- memmove(p + sofar, rb.rp, i);
- e = rb.rp + i;
- if(e == rb.ep)
- e = rb.buf;
- rb.rp = e;
- }
- if(rb.filled && rb.wp == rb.rp){- i = 2*rb.target;
- if(i > sizeof(rb.buf) - 1)
- i = sizeof(rb.buf) - 1;
- rb.target = i;
- rb.filled = 0;
- }
- poperror();
- qunlock(&rb);
+ /* copy chacha state, rekey and increment iv */
+ qlock(rs);
+ c = *rs;
+ chacha_encrypt((uchar*)&rs->input[4], 32, &c);
+ if(++rs->input[13] == 0)
+ if(++rs->input[14] == 0)
+ ++rs->input[15];
+ qunlock(rs);
- wakeup(&rb.producer);
+ /* encrypt the buffer, can fault */
+ chacha_encrypt((uchar*)p, n, &c);
+ /* prevent state leakage */
+ memset(&c, 0, sizeof(c));
+
return n;
+}
+
+/* used by fastrand() */
+void
+genrandom(uchar *p, int n)
+{+ randomread(p, n);
+}
+
+/* used by rand(),nrand() */
+long
+lrand(void)
+{+ /* xoroshiro128+ algorithm */
+ static int seeded = 0;
+ static uvlong s[2];
+ static Lock lk;
+ ulong r;
+
+ if(seeded == 0){+ randomread(s, sizeof(s));
+ seeded = (s[0] | s[1]) != 0;
+ }
+
+ lock(&lk);
+ r = (s[0] + s[1]) >> 33;
+ s[1] ^= s[0];
+ s[0] = (s[0] << 55 | s[0] >> 9) ^ s[1] ^ (s[1] << 14);
+ s[1] = (s[1] << 36 | s[1] >> 28);
+ unlock(&lk);
+
+ return r;
}