X-Git-Url: http://andersk.mit.edu/gitweb/openssh.git/blobdiff_plain/1647c2b5862cb00d0cbc9f48bdb3c076be6671bf..5c305c899bb2ae2ee614b054798047200a0943d4:/helper.c

diff --git a/helper.c b/helper.c
index 91a78b57..bf4e145b 100644
--- a/helper.c
+++ b/helper.c
@@ -45,7 +45,6 @@
 #include <sys/un.h>
 #include <fcntl.h>
 
-#include "rc4.h"
 #include "xmalloc.h"
 #include "ssh.h"
 #include "config.h"
@@ -57,10 +56,58 @@
 
 #ifndef HAVE_ARC4RANDOM
 
+typedef struct
+{
+	unsigned int s[256];
+	int i;
+	int j;
+} rc4_t;
+
 void get_random_bytes(unsigned char *buf, int len);
+void rc4_key(rc4_t *r, unsigned char *key, int len);
+void rc4_getbytes(rc4_t *r, unsigned char *buffer, int len);
 
 static rc4_t *rc4 = NULL;
 
+void rc4_key(rc4_t *r, unsigned char *key, int len)
+{
+	int t;
+	
+	for(r->i = 0; r->i < 256; r->i++)
+		r->s[r->i] = r->i;
+
+	r->j = 0;
+	for(r->i = 0; r->i < 256; r->i++)
+	{
+		r->j = (r->j + r->s[r->i] + key[r->i % len]) % 256;
+		t = r->s[r->i];
+		r->s[r->i] = r->s[r->j];
+		r->s[r->j] = t;
+	}
+	r->i = r->j = 0;
+}
+
+void rc4_getbytes(rc4_t *r, unsigned char *buffer, int len)
+{
+	int t;
+	int c;
+
+	c = 0;	
+	while(c < len)
+	{
+		r->i = (r->i + 1) % 256;
+		r->j = (r->j + r->s[r->i]) % 256;
+		t = r->s[r->i];
+		r->s[r->i] = r->s[r->j];
+		r->s[r->j] = t;
+
+		t = (r->s[r->i] + r->s[r->j]) % 256;
+		
+		buffer[c] = r->s[t];
+		c++;
+	}
+}
+
 unsigned int arc4random(void)
 {
 	unsigned int r;
@@ -117,7 +164,8 @@ void get_random_bytes(unsigned char *buf, int len)
 	
 	/* Send blocking read request to EGD */
 	egd_message[1] = len;
-	c = write(random_pool, egd_message, sizeof(egd_message));
+
+	c = atomicio(write, random_pool, egd_message, sizeof(egd_message));
 	if (c == -1)
 		fatal("Couldn't write to EGD socket \"%s\": %s", RANDOM_POOL, strerror(errno));
 
@@ -129,15 +177,9 @@ void get_random_bytes(unsigned char *buf, int len)
 
 #endif /* HAVE_EGD */
 
-	do {
-		c = read(random_pool, buf, len);
-
-		if ((c == -1) && (errno != EINTR))
-			fatal("Couldn't read from random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
-	} while (c == -1);
-
-	if (c != len)
-		fatal("Short read from random pool \"%s\"", RANDOM_POOL);
+	c = atomicio(read, random_pool, buf, len);
+	if (c <= 0)
+		fatal("Couldn't read from random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
 	
 	close(random_pool);
 }