From: Ben Gras <ben@minix3.org>
Date: Thu, 2 Apr 2009 15:24:44 +0000 (+0000)
Subject: moved type and constants for random data to include file;
X-Git-Tag: v3.1.4~80
X-Git-Url: http://zhaoyanbai.com/repos/doc/%20%22?a=commitdiff_plain;h=9647fbc94e6bbef6553efe93a3fe0249a7c9fa47;p=minix.git

moved type and constants for random data to include file;
added consistency check in random; added source of randomness
internal to random using timing; only retrieve random bins that are full.
---

diff --git a/drivers/random/main.c b/drivers/random/main.c
index a032205f5..d1d135eef 100644
--- a/drivers/random/main.c
+++ b/drivers/random/main.c
@@ -6,9 +6,7 @@
 #include "../drivers.h"
 #include "../libdriver/driver.h"
 #include <sys/ioc_memory.h>
-#include "../../kernel/const.h"
-#include "../../kernel/config.h"
-#include "../../kernel/type.h"
+#include <minix/type.h>
 
 #include "assert.h"
 #include "random.h"
@@ -32,6 +30,7 @@ FORWARD _PROTOTYPE( void r_init, (void) );
 FORWARD _PROTOTYPE( int r_ioctl, (struct driver *dp, message *m_ptr, int safe) );
 FORWARD _PROTOTYPE( void r_geometry, (struct partition *entry) );
 FORWARD _PROTOTYPE( void r_random, (struct driver *dp, message *m_ptr) );
+FORWARD _PROTOTYPE( void r_updatebin, (int source, struct k_randomness_bin *rb));
 
 /* Entry points to this driver. */
 PRIVATE struct driver r_dtab = {
@@ -197,9 +196,30 @@ message *m_ptr;
  *===========================================================================*/
 PRIVATE void r_init()
 {
-  /* Initialize this task. All minor devices are initialized one by one. */
+  static struct k_randomness krandom;
+  int i, s;
+
   random_init();
   r_random(NULL, NULL);				/* also set periodic timer */
+
+  /* Retrieve first randomness buffer with parameters. */
+  if (OK != (s=sys_getrandomness(&krandom))) {
+  	report("RANDOM", "sys_getrandomness failed", s);
+	exit(1);
+  }
+
+  /* Do sanity check on parameters. */
+  if(krandom.random_sources != RANDOM_SOURCES ||
+     krandom.random_elements != RANDOM_ELEMENTS) {
+     printf("random: parameters (%d, %d) don't match kernel's (%d, %d)\n",
+	RANDOM_SOURCES, RANDOM_ELEMENTS,
+	krandom.random_sources, krandom.random_elements);
+     exit(1);
+  }
+
+  /* Feed initial batch. */
+  for(i = 0; i < RANDOM_SOURCES; i++)
+	r_updatebin(i, &krandom.bin[i]);
 }
 
 /*===========================================================================*
@@ -221,6 +241,45 @@ int safe;				/* safe i/o? */
   return(OK);
 }
 
+#define UPDATE(binnumber, bp, startitem, elems) 	{	\
+		rand_t *r, *r2;					\
+		int n = elems, item = startitem;\
+		int high;					\
+		assert(binnumber >= 0 && binnumber < RANDOM_SOURCES);	 \
+		assert(item >= 0 && item < RANDOM_ELEMENTS);	\
+		if(n > 0) {					\
+			high = item+n-1;			\
+			assert(high >= item);				\
+			assert(high >= 0 && high < RANDOM_ELEMENTS);	\
+			r = &bp->r_buf[item];		\
+			r2 = &bp->r_buf[high];		\
+	  		random_update(binnumber, r, n);			\
+		}							\
+}
+
+PRIVATE void r_updatebin(int source, struct k_randomness_bin *rb)
+{
+  	int r_next, r_size, r_high;
+
+  	r_next= rb->r_next;
+  	r_size= rb->r_size;
+
+	assert(r_next >= 0 && r_next < RANDOM_ELEMENTS);
+	assert(r_size >= 0 && r_size <= RANDOM_ELEMENTS);
+
+  	r_high= r_next+r_size;
+
+  	if (r_high <= RANDOM_ELEMENTS) {
+		UPDATE(source, rb, r_next, r_size);
+	} else {
+		assert(r_next < RANDOM_ELEMENTS);
+		UPDATE(source, rb, r_next, RANDOM_ELEMENTS-r_next);
+		UPDATE(source, rb, 0, r_high-RANDOM_ELEMENTS);
+	}
+
+	return;
+}
+
 /*============================================================================*
  *				r_random				      *
  *============================================================================*/
@@ -229,30 +288,21 @@ struct driver *dp;			/* pointer to driver structure */
 message *m_ptr;				/* pointer to alarm message */
 {
   /* Fetch random information from the kernel to update /dev/random. */
-  int i, s, r_next, r_size, r_high;
-  struct randomness krandom;
+  int s;
+  static int bin = 0;
+  static struct k_randomness_bin krandom_bin;
+  u32_t hi, lo;
+  rand_t r;
 
-  if (OK != (s=sys_getrandomness(&krandom)))
-  	report("RANDOM", "sys_getrandomness failed", s);
+  bin = (bin+1) % RANDOM_SOURCES;
 
-  for (i= 0; i<RANDOM_SOURCES; i++)	
-  {
-  	r_next= krandom.bin[i].r_next;
-  	r_size= krandom.bin[i].r_size;
-  	r_high= r_next+r_size;
-  	if (r_high <= RANDOM_ELEMENTS)
-  	{
-  		random_update(i, &krandom.bin[i].r_buf[r_next], r_size);
-	}
-	else
-	{
-		assert(r_next < RANDOM_ELEMENTS);
-  		random_update(i, &krandom.bin[i].r_buf[r_next],
-  			RANDOM_ELEMENTS-r_next);
-  		random_update(i, &krandom.bin[i].r_buf[0],
-  			r_high-RANDOM_ELEMENTS);
-	}
-  }
+  if(sys_getrandom_bin(&krandom_bin, bin) == OK)
+	r_updatebin(bin, &krandom_bin);
+
+  /* Add our own timing source. */
+  read_tsc(&hi, &lo);
+  r = lo;
+  random_update(RND_TIMING, &r, 1);
 
   /* Schedule new alarm for next m_random call. */
   if (OK != (s=sys_setalarm(KRANDOM_PERIOD, 0)))
diff --git a/drivers/random/random.c b/drivers/random/random.c
index ce15c1755..001a1a78f 100644
--- a/drivers/random/random.c
+++ b/drivers/random/random.c
@@ -21,8 +21,8 @@ that data into a seed for a psuedo random number generator.
 				 * re-seed.
 				 */
 
-PRIVATE unsigned long deriv[RANDOM_SOURCES][N_DERIV];
-PRIVATE int pool_ind[RANDOM_SOURCES];
+PRIVATE unsigned long deriv[TOTAL_SOURCES][N_DERIV];
+PRIVATE int pool_ind[TOTAL_SOURCES];
 PRIVATE SHA256_CTX pool_ctx[NR_POOLS];
 PRIVATE unsigned samples= 0;
 PRIVATE int got_seeded= 0;
@@ -39,10 +39,10 @@ PUBLIC void random_init()
 {
 	int i, j;
 
-	assert(&deriv[RANDOM_SOURCES-1][N_DERIV-1] ==
-		&deriv[0][0] + RANDOM_SOURCES*N_DERIV -1);
+	assert(&deriv[TOTAL_SOURCES-1][N_DERIV-1] ==
+		&deriv[0][0] + TOTAL_SOURCES*N_DERIV -1);
 
-	for (i= 0; i<RANDOM_SOURCES; i++)
+	for (i= 0; i<TOTAL_SOURCES; i++)
 	{
 		for (j= 0; j<N_DERIV; j++)
 			deriv[i][j]= 0;
@@ -64,7 +64,7 @@ PUBLIC int random_isseeded()
 
 PUBLIC void random_update(source, buf, count)
 int source;
-unsigned short *buf;
+rand_t *buf;
 int count;
 {
 	int i;
@@ -72,7 +72,7 @@ int count;
 #if 0
 	printf("random_update: got %d samples for source %d\n", count, source);
 #endif
-	if (source < 0 || source >= RANDOM_SOURCES)
+	if (source < 0 || source >= TOTAL_SOURCES)
 		panic("memory", "random_update: bad source", source);
 	for (i= 0; i<count; i++)
 		add_sample(source, buf[i]);
diff --git a/drivers/random/random.h b/drivers/random/random.h
index f1318aad2..2930eb230 100644
--- a/drivers/random/random.h
+++ b/drivers/random/random.h
@@ -4,9 +4,13 @@ random.h
 Public interface to the random number generator 
 */
 
+/* Internal random sources */
+#define RND_TIMING		0
+#define RANDOM_SOURCES_INTERNAL	1
+#define TOTAL_SOURCES	(RANDOM_SOURCES+RANDOM_SOURCES_INTERNAL)
+
 _PROTOTYPE( void random_init, (void)					);
 _PROTOTYPE( int random_isseeded, (void)					);
-_PROTOTYPE( void random_update, (int source, unsigned short *buf, 
-							int count)	);
+_PROTOTYPE( void random_update, (int source, rand_t *buf, int count)	);
 _PROTOTYPE( void random_getbytes, (void *buf, size_t size)		);
 _PROTOTYPE( void random_putbytes, (void *buf, size_t size)		);
diff --git a/include/minix/com.h b/include/minix/com.h
index 50a13c87a..267c18734 100755
--- a/include/minix/com.h
+++ b/include/minix/com.h
@@ -461,6 +461,7 @@
 #   define GET_PRIVID	  17	/* get ID of privilege structure */
 #   define GET_HZ	  18	/* get HZ value */
 #   define GET_WHOAMI	  19	/* get own name and endpoint */
+#   define GET_RANDOMNESS_BIN 20 /* get one randomness bin */
 #define I_ENDPT      m7_i4	/* calling process */
 #define I_VAL_PTR      m7_p1	/* virtual address at caller */ 
 #define I_VAL_LEN      m7_i1	/* max length of value */
diff --git a/include/minix/syslib.h b/include/minix/syslib.h
index 24f394b82..d4facdc2c 100755
--- a/include/minix/syslib.h
+++ b/include/minix/syslib.h
@@ -156,6 +156,7 @@ _PROTOTYPE(int sys_segctl, (int *index, u16_t *seg, vir_bytes *off,
 #define sys_getprivtab(dst)	sys_getinfo(GET_PRIVTAB, dst, 0,0,0)
 #define sys_getproc(dst,nr)	sys_getinfo(GET_PROC, dst, 0,0, nr)
 #define sys_getrandomness(dst)	sys_getinfo(GET_RANDOMNESS, dst, 0,0,0)
+#define sys_getrandom_bin(d,b)	sys_getinfo(GET_RANDOMNESS_BIN, d, 0,0,b)
 #define sys_getimage(dst)	sys_getinfo(GET_IMAGE, dst, 0,0,0)
 #define sys_getirqhooks(dst)	sys_getinfo(GET_IRQHOOKS, dst, 0,0,0)
 #define sys_getirqactids(dst)	sys_getinfo(GET_IRQACTIDS, dst, 0,0,0)
diff --git a/include/minix/sysutil.h b/include/minix/sysutil.h
index 31a1edb01..e0b2987b8 100644
--- a/include/minix/sysutil.h
+++ b/include/minix/sysutil.h
@@ -58,6 +58,8 @@ _PROTOTYPE( int micro_delay, (u32_t micros));
 _PROTOTYPE( u32_t micros_to_ticks, (u32_t micros));
 _PROTOTYPE( int asynsend, (endpoint_t ep, message *msg));
 _PROTOTYPE( void ser_putc, (char c));
+_PROTOTYPE( void get_randomness, (struct k_randomness *, int));
+
 
 #define ASSERT(c) if(!(c)) { panic(__FILE__, "assert " #c " failed at line", __LINE__); }
 
diff --git a/include/minix/type.h b/include/minix/type.h
index 8be6b33a6..7d182348d 100755
--- a/include/minix/type.h
+++ b/include/minix/type.h
@@ -178,6 +178,22 @@ struct kmessages {
   char km_buf[_KMESS_BUF_SIZE];          /* buffer for messages */
 };
 
+#include <ibm/interrupt.h>
+
+/* randomness struct: random sources after interrupts: */
+#define RANDOM_SOURCES			NR_IRQ_VECTORS
+#define RANDOM_ELEMENTS			64
+
+typedef unsigned short rand_t;
+
+struct k_randomness {
+  int random_elements, random_sources;
+  struct k_randomness_bin {
+        int r_next;                             /* next index to write */
+        int r_size;                             /* number of random elements */
+        rand_t r_buf[RANDOM_ELEMENTS]; /* buffer for random info */
+  } bin[RANDOM_SOURCES];
+};
 
 #endif /* _TYPE_H */
 
diff --git a/kernel/arch/i386/do_int86.c b/kernel/arch/i386/do_int86.c
index 9ff1db876..6b7510e1a 100644
--- a/kernel/arch/i386/do_int86.c
+++ b/kernel/arch/i386/do_int86.c
@@ -36,7 +36,7 @@ register message *m_ptr;	/* pointer to request message */
    * not very random.
    */
   lock;
-  get_randomness(CLOCK_IRQ);
+  get_randomness(&krandom, CLOCK_IRQ);
   unlock;
 
   return(OK);
diff --git a/kernel/config.h b/kernel/config.h
index 0fb906db7..2c0203930 100644
--- a/kernel/config.h
+++ b/kernel/config.h
@@ -49,11 +49,6 @@
  */
 #define P_NAME_LEN	   8
 
-/* Buffer to gather randomness. This is used to generate a random stream by 
- * the MEMORY driver when reading from /dev/random. 
- */
-#define RANDOM_ELEMENTS   32
-
 /* This section contains defines for valuable system resources that are used
  * by device drivers. The number of elements of the vectors is determined by 
  * the maximum needed by any given driver. The number of interrupt hooks may
diff --git a/kernel/const.h b/kernel/const.h
index 62588b35c..c3f1ea008 100755
--- a/kernel/const.h
+++ b/kernel/const.h
@@ -25,9 +25,6 @@
 #define _SRC_	0
 #define _DST_	1
 
-/* Number of random sources */
-#define RANDOM_SOURCES	16
-
 #define get_sys_bit(map,bit) \
 	( MAP_CHUNK(map.chunk,bit) & (1 << CHUNK_OFFSET(bit) )
 #define get_sys_bits(map,bit) \
diff --git a/kernel/glo.h b/kernel/glo.h
index 8e240324d..e3ed5735b 100755
--- a/kernel/glo.h
+++ b/kernel/glo.h
@@ -25,7 +25,7 @@ EXTERN char shutdown_started;		/* TRUE after shutdowns / reboots */
 EXTERN struct kinfo kinfo;		/* kernel information for users */
 EXTERN struct machine machine;		/* machine information for users */
 EXTERN struct kmessages kmess;  	/* diagnostic messages in kernel */
-EXTERN struct randomness krandom;	/* gather kernel random information */
+EXTERN struct k_randomness krandom;	/* gather kernel random information */
 EXTERN struct loadinfo kloadinfo;	/* status of load average */
 
 /* Process scheduling information and the kernel reentry count. */
diff --git a/kernel/main.c b/kernel/main.c
index 05bf762fd..1ef2474aa 100755
--- a/kernel/main.c
+++ b/kernel/main.c
@@ -175,6 +175,8 @@ PUBLIC void main()
   cprof_procs_no = 0;  /* init nr of hash table slots used */
 
   vm_running = 0;
+  krandom.random_sources = RANDOM_SOURCES;
+  krandom.random_elements = RANDOM_ELEMENTS;
 
   /* MINIX is now ready. All boot image processes are on the ready queue.
    * Return to the assembly code to start running the current process. 
diff --git a/kernel/proto.h b/kernel/proto.h
index 71edffa56..a3070efdd 100755
--- a/kernel/proto.h
+++ b/kernel/proto.h
@@ -58,7 +58,6 @@ _PROTOTYPE( int get_priv, (register struct proc *rc, int proc_type)	);
 _PROTOTYPE( void send_sig, (int proc_nr, int sig_nr)			);
 _PROTOTYPE( void cause_sig, (int proc_nr, int sig_nr)			);
 _PROTOTYPE( void sys_task, (void)					);
-_PROTOTYPE( void get_randomness, (int source)				);
 #define numap_local(proc_nr, vir_addr, bytes) \
 	umap_local(proc_addr(proc_nr), D, (vir_addr), (bytes))
 _PROTOTYPE( phys_bytes umap_grant, (struct proc *, cp_grant_id_t,
diff --git a/kernel/system.c b/kernel/system.c
index 03f4f9d3c..77642f62b 100755
--- a/kernel/system.c
+++ b/kernel/system.c
@@ -290,28 +290,6 @@ int proc_type;				/* system or user process flag */
   return(OK);
 }
 
-/*===========================================================================*
- *				get_randomness				     *
- *===========================================================================*/
-PUBLIC void get_randomness(source)
-int source;
-{
-/* Use architecture-dependent high-resolution clock for
- * raw entropy gathering.
- */
-  int r_next;
-  unsigned long tsc_high, tsc_low;
-
-  source %= RANDOM_SOURCES;
-  r_next= krandom.bin[source].r_next;
-  read_tsc(&tsc_high, &tsc_low);
-  krandom.bin[source].r_buf[r_next] = tsc_low;
-  if (krandom.bin[source].r_size < RANDOM_ELEMENTS) {
-  	krandom.bin[source].r_size ++;
-  }
-  krandom.bin[source].r_next = (r_next + 1 ) % RANDOM_ELEMENTS;
-}
-
 /*===========================================================================*
  *				send_sig				     *
  *===========================================================================*/
diff --git a/kernel/system/do_getinfo.c b/kernel/system/do_getinfo.c
index 5c4062e10..e40889e1c 100644
--- a/kernel/system/do_getinfo.c
+++ b/kernel/system/do_getinfo.c
@@ -31,6 +31,7 @@ register message *m_ptr;	/* pointer to request message */
   int proc_nr, nr_e, nr;
   struct proc *caller;
   phys_bytes ph;
+  int wipe_rnd_bin = -1;
 
   caller = proc_addr(who_p);
 
@@ -112,7 +113,7 @@ register message *m_ptr;	/* pointer to request message */
         break;
     }
     case GET_RANDOMNESS: {		
-        static struct randomness copy;		/* copy to keep counters */
+        static struct k_randomness copy;	/* copy to keep counters */
 	int i;
 
         copy = krandom;
@@ -120,10 +121,28 @@ register message *m_ptr;	/* pointer to request message */
   		krandom.bin[i].r_size = 0;	/* invalidate random data */
   		krandom.bin[i].r_next = 0;
 	}
-    	length = sizeof(struct randomness);
+    	length = sizeof(copy);
     	src_vir = (vir_bytes) &copy;
     	break;
     }
+    case GET_RANDOMNESS_BIN: {		
+	int i, bin = m_ptr->I_VAL_LEN2_E;
+
+	if(bin < 0 || bin >= RANDOM_SOURCES) {
+		kprintf("SYSTEM: GET_RANDOMNESS_BIN: %d out of range\n", bin);
+		return EINVAL;
+	}
+
+	if(krandom.bin[bin].r_size < RANDOM_ELEMENTS)
+		return ENOENT;
+
+    	length = sizeof(krandom.bin[bin]);
+    	src_vir = (vir_bytes) &krandom.bin[bin];
+
+	wipe_rnd_bin = bin;
+
+    	break;
+    }
     case GET_KMESSAGES: {
         length = sizeof(struct kmessages);
         src_vir = (vir_bytes) &kmess;
@@ -158,7 +177,12 @@ register message *m_ptr;	/* pointer to request message */
   if((ph=umap_local(caller, D, (vir_bytes) m_ptr->I_VAL_PTR,length)) == 0)
 	return EFAULT;
   CHECKRANGE_OR_SUSPEND(caller, ph, length, 1);
-  data_copy(SYSTEM, src_vir, who_e, (vir_bytes) m_ptr->I_VAL_PTR, length);
+  if(data_copy(SYSTEM, src_vir, who_e, (vir_bytes) m_ptr->I_VAL_PTR, length) == OK) {
+	if(wipe_rnd_bin >= 0 && wipe_rnd_bin < RANDOM_SOURCES) {
+		krandom.bin[wipe_rnd_bin].r_size = 0;
+		krandom.bin[wipe_rnd_bin].r_next = 0;
+	}
+  }
   return(OK);
 }
 
diff --git a/kernel/system/do_irqctl.c b/kernel/system/do_irqctl.c
index 9625a9825..53893c391 100644
--- a/kernel/system/do_irqctl.c
+++ b/kernel/system/do_irqctl.c
@@ -142,7 +142,7 @@ irq_hook_t *hook;
   /* As a side-effect, the interrupt handler gathers random information by 
    * timestamping the interrupt events. This is used for /dev/random.
    */
-  get_randomness(hook->irq);
+  get_randomness(&krandom, hook->irq);
 
   /* Check if the handler is still alive.
    * If it's dead, this should never happen, as processes that die 
diff --git a/kernel/type.h b/kernel/type.h
index 8f3b6864b..f09939737 100755
--- a/kernel/type.h
+++ b/kernel/type.h
@@ -2,6 +2,7 @@
 #define TYPE_H
 
 #include <minix/com.h>
+#include <ibm/interrupt.h>
 
 typedef _PROTOTYPE( void task_t, (void) );
 
@@ -27,14 +28,6 @@ struct boot_image {
   endpoint_t endpoint;			/* endpoint number when started */
 };
 
-struct randomness {
-  struct {
-	int r_next;				/* next index to write */
-	int r_size;				/* number of random elements */
-	unsigned short r_buf[RANDOM_ELEMENTS]; /* buffer for random info */
-  } bin[RANDOM_SOURCES];
-};
-
 typedef unsigned long irq_policy_t;	
 typedef unsigned long irq_id_t;	
 
diff --git a/lib/sysutil/Makefile.in b/lib/sysutil/Makefile.in
index 4f348804f..a44addf98 100644
--- a/lib/sysutil/Makefile.in
+++ b/lib/sysutil/Makefile.in
@@ -10,6 +10,7 @@ libsys_FILES=" \
 	kprintf.c \
 	kputc.c \
 	tickdelay.c \
+	get_randomness.c \
 	getuptime.c \
 	getuptime2.c \
 	env_get_prm.c \
diff --git a/lib/sysutil/get_randomness.c b/lib/sysutil/get_randomness.c
new file mode 100644
index 000000000..a52a1e267
--- /dev/null
+++ b/lib/sysutil/get_randomness.c
@@ -0,0 +1,34 @@
+#include <lib.h>
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <minix/profile.h>
+#include <minix/syslib.h>
+#include <minix/type.h>
+#include <minix/sysutil.h>
+
+/*===========================================================================*
+ *                              get_randomness                               *
+ *===========================================================================*/
+PUBLIC void get_randomness(rand, source)
+struct k_randomness *rand;
+int source;
+{
+/* Use architecture-dependent high-resolution clock for
+ * raw entropy gathering.
+ */
+  int r_next;
+  unsigned long tsc_high, tsc_low;
+ 
+  source %= RANDOM_SOURCES;
+  r_next= rand->bin[source].r_next;  
+  read_tsc(&tsc_high, &tsc_low);  
+  rand->bin[source].r_buf[r_next] = tsc_low;  
+  if (rand->bin[source].r_size < RANDOM_ELEMENTS) {  
+        rand->bin[source].r_size ++;  
+  }
+  rand->bin[source].r_next = (r_next + 1 ) % RANDOM_ELEMENTS;  
+} 
+  
+