Small update to random number generator

diff --git a/drivers/memory/memory.c b/drivers/memory/memory.c
index 90cd512bdb602e1a8d74aa8cfe413400e881dfdf..6ffd44baa19a6b704bd152093c71bfb176d1690e 100644 (file)
--- a/drivers/memory/memory.c
+++ b/drivers/memory/memory.c
@@ -27,7 +27,7 @@
 #include "random.h"
 
 #define NR_DEVS            7           /* number of minor devices */
-#define KRANDOM_PERIOD    10           /* ticks between krandom calls */
+#define KRANDOM_PERIOD    1            /* ticks between krandom calls */
 
 PRIVATE struct device m_geom[NR_DEVS];  /* base and size of each device */
 PRIVATE int m_seg[NR_DEVS];            /* segment index of each device */
@@ -183,12 +183,8 @@ unsigned nr_req;           /* length of request vector */
 
        /* Random number generator. Character instead of block device. */
        case RANDOM_DEV:
-           if (opcode == DEV_GATHER)
-           {
-               s= random_reseed();
-               if (s < 0)
+           if (opcode == DEV_GATHER && !random_isseeded())
                    return(EAGAIN);
-           }
            left = count;
            while (left > 0) {
                chunk = (left > RANDOM_BUF_SIZE) ? RANDOM_BUF_SIZE : left;

diff --git a/drivers/memory/random.c b/drivers/memory/random.c
index f58236ea60921adfe20f3723504421058e1ed989..f49320480d73c750e14e6c112ef8ceada30a5d3d 100644 (file)
--- a/drivers/memory/random.c
+++ b/drivers/memory/random.c
@@ -33,6 +33,7 @@ PRIVATE u32_t reseed_count;
 FORWARD _PROTOTYPE( void add_sample, (int source, unsigned long sample)        );
 FORWARD _PROTOTYPE( void data_block, (rd_keyinstance *keyp,
                                                        void *data)     );
+FORWARD _PROTOTYPE( void reseed, (void)                                        );
 
 PUBLIC void random_init()
 {
@@ -54,42 +55,11 @@ PUBLIC void random_init()
        reseed_count= 0;
 }
 
-PUBLIC int random_reseed()
+PUBLIC int random_isseeded()
 {
-       int i;
-       SHA256_CTX ctx;
-       u8_t digest[SHA256_DIGEST_LENGTH];
-
-       if (samples >= MIN_SAMPLES)
-       {
-               reseed_count++;
-               printf("random_reseed:  round %d, samples = %d\n",
-                       reseed_count, samples);
-               SHA256_Init(&ctx);
-               if (got_seeded)
-                       SHA256_Update(&ctx, random_key, sizeof(random_key));
-               SHA256_Final(digest, &pool_ctx[0]);
-               SHA256_Update(&ctx, digest, sizeof(digest));
-               SHA256_Init(&pool_ctx[0]);
-               for (i= 1; i<NR_POOLS; i++)
-               {
-                       if ((reseed_count & (1UL << (i-1))) != 0)
-                               break;
-                       printf("random_reseed: adding pool %d\n", i);
-                       SHA256_Final(digest, &pool_ctx[i]);
-                       SHA256_Update(&ctx, digest, sizeof(digest));
-                       SHA256_Init(&pool_ctx[i]);
-               }
-               SHA256_Final(digest, &ctx);
-               assert(sizeof(random_key) == sizeof(digest));
-               memcpy(random_key, &digest, sizeof(random_key));
-               samples= 0;
-
-               got_seeded= 1;
-       }
        if (got_seeded)
-               return 0;
-       return -1;
+               return 1;
+       return 0;
 }
 
 PUBLIC void random_update(source, buf, count)
@@ -106,6 +76,7 @@ int count;
                panic("memory", "random_update: bad source", source);
        for (i= 0; i<count; i++)
                add_sample(source, buf[i]);
+       reseed();
 }
 
 PUBLIC void random_getbytes(buf, size)
@@ -153,6 +124,8 @@ size_t size;
         * with the number of bits.
         */
        samples += size*8;
+
+       reseed();
 }
 
 PRIVATE void add_sample(source, sample)
@@ -230,3 +203,38 @@ void *data;
        if (count_lo == 0)
                count_hi++;
 }
+
+PRIVATE void reseed()
+{
+       int i;
+       SHA256_CTX ctx;
+       u8_t digest[SHA256_DIGEST_LENGTH];
+
+       if (samples < MIN_SAMPLES)
+               return;
+
+       reseed_count++;
+       printf("reseed: round %d, samples = %d\n", reseed_count, samples);
+       SHA256_Init(&ctx);
+       if (got_seeded)
+               SHA256_Update(&ctx, random_key, sizeof(random_key));
+       SHA256_Final(digest, &pool_ctx[0]);
+       SHA256_Update(&ctx, digest, sizeof(digest));
+       SHA256_Init(&pool_ctx[0]);
+       for (i= 1; i<NR_POOLS; i++)
+       {
+               if ((reseed_count & (1UL << (i-1))) != 0)
+                       break;
+               printf("random_reseed: adding pool %d\n", i);
+               SHA256_Final(digest, &pool_ctx[i]);
+               SHA256_Update(&ctx, digest, sizeof(digest));
+               SHA256_Init(&pool_ctx[i]);
+       }
+       SHA256_Final(digest, &ctx);
+       assert(sizeof(random_key) == sizeof(digest));
+       memcpy(random_key, &digest, sizeof(random_key));
+       samples= 0;
+
+       got_seeded= 1;
+}
+

diff --git a/drivers/memory/random.h b/drivers/memory/random.h
index d238f397cb34fd3712bccc4a510e10f1c2caae56..ffd6b3694c0df044f2deae716677d5773ea1e981 100644 (file)
--- a/drivers/memory/random.h
+++ b/drivers/memory/random.h
@@ -5,7 +5,7 @@ Public interface to the random number generator
 */
 
 _PROTOTYPE( void random_init, (void)                                   );
-_PROTOTYPE( int random_reseed, (void)                                  );
+_PROTOTYPE( int random_isseeded, (void)                                        );
 _PROTOTYPE( void random_update, (int source, unsigned long *buf, 
                                                        int count)      );
 _PROTOTYPE( void random_getbytes, (void *buf, size_t size)             );

diff --git a/etc/usr/rc b/etc/usr/rc
index 7696ff48be362fc1562a7143c19efeb3226c6ddb..106bcd79f224a56459f7194a0b44d2a14621f8dd 100644 (file)
--- a/etc/usr/rc
+++ b/etc/usr/rc
@@ -26,6 +26,8 @@ daemonize()
     done
 }
 
+RANDOM_FILE=/usr/adm/random.dat
+
 case $action in
 start)
     # Select console font.
@@ -34,6 +36,14 @@ start)
     # Cleanup.
     rm -rf /tmp/. /usr/run/. /usr/spool/lpd/. /usr/spool/locks/.
 
+    # load random number generator
+    if [ -f $RANDOM_FILE ]
+    then
+       cat < $RANDOM_FILE >/dev/random
+       # overwrite $RANDOM_FILE. We don't want to use this data again
+       dd if=/dev/random of=$RANDOM_FILE bs=1024 count=1
+    fi
+
     # Start servers.
     ifs="$IFS"; IFS=,
     for server in `sysenv servers`; do daemonize $server; done
@@ -106,4 +116,14 @@ prompt to investigate, otherwise just wait until an address is received..."
 
     # Run the daily cleanup on systems that are not on at night.
     test -f /usr/etc/daily && sh /usr/etc/daily boot &
+
+;;
+stop|down)
+       # Save random data.
+       if dd if=/dev/random of=$RANDOM_FILE.new bs=1024 count=1 2>/dev/null
+       then
+               mv $RANDOM_FILE.new $RANDOM_FILE
+       else
+               echo 'Failed to save random data.'
+       fi
 esac