X-Git-Url: https://git.distorted.org.uk/~mdw/catacomb/blobdiff_plain/0f00dc4c8eb47e67bc0f148c2dd109f73a451e0a..61bd904b61ef893246791746517ef7a38ed732db:/rand/noise.c?ds=sidebyside

diff --git a/rand/noise.c b/rand/noise.c
index 6ab1070f..3bece706 100644
--- a/rand/noise.c
+++ b/rand/noise.c
@@ -30,9 +30,10 @@
 #include "config.h"
 
 #include <setjmp.h>
+#include <signal.h>
 #include <stdio.h>
+#include <stdlib.h>
 #include <string.h>
-#include <signal.h>
 
 #include <sys/types.h>
 #include <sys/time.h>
@@ -46,6 +47,8 @@
 #endif
 
 #include <mLib/bits.h>
+#include <mLib/mdup.h>
+#include <mLib/sel.h>
 #include <mLib/tv.h>
 
 #include "noise.h"
@@ -113,6 +116,7 @@ static int timer(rand_pool *r, struct timeval *tv)
   x = tv->tv_usec + MILLION * tv->tv_sec;
   d = x ^ noise_last;
   dd = d ^ noise_diff;
+  noise_last = x;
   noise_diff = d;
   de = bitcount(d);
   dde = bitcount(dd);
@@ -156,6 +160,7 @@ int noise_devrandom(rand_pool *r)
   int fd;
   octet buf[RAND_POOLSZ];
   ssize_t len;
+  size_t n = 0;
   int ret = 0;
 
   /* --- Be nice to other clients of the random device --- *
@@ -169,11 +174,13 @@ int noise_devrandom(rand_pool *r)
   if ((fd = open("/dev/urandom", O_RDONLY | O_NONBLOCK)) >= 0 ||
       (fd = open("/dev/arandom", O_RDONLY | O_NONBLOCK)) >= 0 ||
       (fd = open("/dev/random", O_RDONLY | O_NONBLOCK)) >= 0) {
-    if ((len = read(fd, buf, sizeof(buf))) > 0) {
-      rand_add(r, buf, len, len * 8);
-      BURN(buf);
-      ret = 1;
+    while (n < sizeof(buf)) {
+      if ((len = read(fd, buf + n, sizeof(buf) - n)) <= 0) break;
+      n += len;
     }
+    rand_add(r, buf, n, n * 8);
+    BURN(buf);
+    if (n == sizeof(buf)) ret = 1;
     close(fd);
   }
   noise_timer(r);
@@ -222,13 +229,43 @@ void noise_setid(uid_t uid, gid_t gid)
  *		This interface is Unix-specific.
  */
 
+struct noisekid {
+  rand_pool *r;
+  int good;
+  char buf[4096];
+  int donep;
+  int ret;
+};
+
+static void kid_read(int fd, unsigned mode, void *p)
+{
+  struct noisekid *nk = p;
+  ssize_t sz;
+  int goodbits;
+
+  noise_timer(nk->r);
+  if ((sz = read(fd, nk->buf, sizeof(nk->buf))) <= 0)
+    nk->donep = 1;
+  else {
+    goodbits = (sz * nk->good) / 128;
+    rand_add(nk->r, nk->buf, sz, goodbits);
+    nk->ret = 1;
+  }
+}
+
+static void kid_dead(struct timeval *tv, void *p)
+  { struct noisekid *nk = p; nk->donep = 1; }
+
 int noise_filter(rand_pool *r, int good, const char *c)
 {
-  char buf[4096];
   pid_t kid;
   int fd[2];
   struct timeval dead;
   int ret = 0;
+  struct noisekid nk = { 0 };
+  sel_state sel;
+  sel_file sf;
+  sel_timer st;
   const char *env[] = {
     "PATH=/bin:/usr/bin:/sbin:/usr/sbin:/etc",
     0
@@ -257,20 +294,16 @@ int noise_filter(rand_pool *r, int good, const char *c)
   /* --- Handle the child end of the deal --- */
 
   if (kid == 0) {
-    int f;
+    mdup_fd mfd[3];
+    int f, i = 0;
 
     /* --- Set the pipe as standard output, close standard input --- */
 
-    close(0); close(1); close(2);
-
-    if (fd[1] != 1) {
-      if (dup2(fd[1], 1) < 0) _exit(127);
-      close(fd[1]);
-    }
-
-    if ((f = open("/dev/null", O_RDONLY)) != 0 ||
-	(f = open("/dev/null", O_WRONLY)) != 2)
-      _exit(127);
+    if ((f = open("/dev/null", O_RDONLY)) < 0) _exit(127);
+    mfd[i].cur = f; mfd[i].want = 0; i++;
+    mfd[i].cur = fd[1]; mfd[i].want = 1; i++;
+    mfd[i].cur = f; mfd[i].want = 2; i++;
+    if (mdup(mfd, i)) _exit(127);
 
     /* --- Play games with uids --- */
 
@@ -289,46 +322,20 @@ int noise_filter(rand_pool *r, int good, const char *c)
 
     /* --- Start the process up --- */
 
-    execle("/bin/sh", "-c", c, (char *)0, env);
+    execle("/bin/sh", "sh", "-c", c, (char *)0, env);
     _exit(127);
   }
 
   /* --- Sort out my end of the deal --- */
 
   close(fd[1]);
-
-  /* --- Decide on the deadline --- */
-
+  sel_init(&sel);
+  nk.r = r; nk.good = good;
   TV_ADDL(&dead, &dead, 0, NOISE_KIDLIFE);
-
-  /* --- Now read, and think --- */
-
-  for (;;) {
-    struct timeval now, diff;
-    fd_set rd;
-
-    gettimeofday(&now, 0);
-    timer(r, &now);
-    if (TV_CMP(&now, >, &dead))
-      break;
-    TV_SUB(&diff, &dead, &now);
-
-    FD_ZERO(&rd);
-    FD_SET(fd[0], &rd);
-
-    if (select(fd[0] + 1, &rd, 0, 0, &diff) < 0)
-      break;
-    if (FD_ISSET(fd[0], &rd)) {
-      ssize_t sz;
-      int goodbits;
-
-      if ((sz = read(fd[0], buf, sizeof(buf))) <= 0)
-	break;
-      goodbits = (sz * good) / 128;
-      rand_add(r, buf, sz, goodbits);
-      ret = 1;
-    }
-  }
+  sel_initfile(&sel, &sf, fd[0], SEL_READ, kid_read, &nk);
+  sel_addfile(&sf);
+  sel_addtimer(&sel, &st, &dead, kid_dead, &nk);
+  while (!nk.donep && !sel_select(&sel));
 
   /* --- We've finished with it: kill the child process --- *
    *
@@ -338,11 +345,11 @@ int noise_filter(rand_pool *r, int good, const char *c)
    */
 
   close(fd[0]);
-  BURN(buf);
+  BURN(nk.buf);
   noise_timer(r);
   kill(kid, SIGKILL);
   waitpid(kid, 0, 0);
-  return (ret);
+  return (nk.ret);
 }
 
 /* --- @noise_freewheel@ --- *
@@ -449,7 +456,7 @@ void noise_acquire(rand_pool *r)
   unsigned i;
   for (i = 0; i < 8; i++)
     noise_freewheel(r);
-  if (!noise_devrandom(r)) {
+  if (!noise_devrandom(r) || getenv("CATACOMB_FORCE_ESOTERIC_SOURCES")) {
     noise_enquire(r);
     for (i = 0; i < 8; i++)
       noise_freewheel(r);