Import of spilt-off random collection code

1 files changed, 124 insertions, 0 deletions

diff --git a/random.c b/random.c
new file mode 100644
index 000000000..06c8d2b3c
--- /dev/null
+++ b/random.c
@@ -0,0 +1,124 @@
+/*
+**
+** Random number collection
+**
+** Damien Miller <djm@ibs.com.au>
+** 
+** Copyright 1999 Damien Miller
+**
+** Permission is hereby granted, free of charge, to any person
+** obtaining a copy of this software and associated documentation
+** files (the "Software"), to deal in the Software without
+** restriction, including without limitation the rights to use, copy,
+** modify, merge, publish, distribute, sublicense, and/or sell copies
+** of the Software, and to permit persons to whom the Software is
+** furnished to do so, subject to the following conditions:
+**
+** The above copyright notice and this permission notice shall be
+** included in all copies or substantial portions of the Software.
+**
+** THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY
+** KIND, EXPRESS OR IMPLIED, INCLUDING BUT NOT LIMITED TO THE
+** WARRANTIES OF MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE
+** AND NONINFRINGEMENT.  IN NO EVENT SHALL DAMIEN MILLER OR INTERNET
+** BUSINESS SOLUTIONS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+** LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE,
+** ARISING FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE
+** OR OTHER DEALINGS IN THE SOFTWARE.
+**
+** Except as contained in this notice, the name of Internet Business
+** Solutions shall not be used in advertising or otherwise to promote
+** the sale, use or other dealings in this Software without prior
+** written authorization from Internet Business Solutions.
+**
+*/
+
+#include <stdio.h>
+#include <stdlib.h>
+#include <string.h>
+#include <errno.h>
+#include <unistd.h>
+
+#include <sys/types.h>
+#include <sys/stat.h>
+#include <sys/socket.h>
+#include <sys/un.h>
+#include <fcntl.h>
+#ifdef HAVE_STDDEF_H
+#include <stddef.h>
+#endif
+
+#include "ssh.h"
+#include "xmalloc.h"
+#include "random.h"
+
+#ifndef offsetof
+# define offsetof(type, member) ((size_t) &((type *)0)->member)
+#endif
+
+#ifdef HAVE_EGD
+
+/* Collect entropy from EGD */
+void get_random_bytes(unsigned char *buf, int len)
+{
+        static int random_pool;
+        int c;
+        char egd_message[2] = { 0x02, 0x00 };
+        struct sockaddr_un addr;
+        int addr_len;
+
+        memset(&addr, '\0', sizeof(addr));
+        addr.sun_family = AF_UNIX;
+        
+        /* FIXME: compile time check? */
+        if (sizeof(RANDOM_POOL) > sizeof(addr.sun_path))
+                fatal("Random pool path is too long");
+        
+        strcpy(addr.sun_path, RANDOM_POOL);
+        
+        addr_len = offsetof(struct sockaddr_un, sun_path) + sizeof(RANDOM_POOL);
+        
+        random_pool = socket(AF_UNIX, SOCK_STREAM, 0);
+        
+        if (random_pool == -1)
+                fatal("Couldn't create AF_UNIX socket: %s", strerror(errno));
+        
+        if (connect(random_pool, (struct sockaddr*)&addr, addr_len) == -1)
+                fatal("Couldn't connect to EGD socket \"%s\": %s", addr.sun_path, strerror(errno));
+
+        if (len > 255)
+                fatal("Too many bytes to read from EGD");
+        
+        /* Send blocking read request to EGD */
+        egd_message[1] = len;
+
+        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));
+
+        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);
+}
+#else /* HAVE_EGD */
+
+/* Collect entropy from /dev/urandom or pipe */
+void get_random_bytes(unsigned char *buf, int len)
+{
+        static int random_pool;
+        int c;
+
+        random_pool = open(RANDOM_POOL, O_RDONLY);
+        if (random_pool == -1)
+                fatal("Couldn't open random pool \"%s\": %s", RANDOM_POOL, strerror(errno));
+
+        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);
+}
+
+#endif /* HAVE_EGD */