- Big OpenBSD CVS update (mainly beginnings of SSH2 infrastructure)

[openssh.git] / bufaux.c

diff --git a/bufaux.c b/bufaux.c
index 422584bd2a94e9d79b3039662099fad0f691342d..aa95cb3f06811e8bb2f7e97a24f74d89a27bbf1b 100644 (file)
--- a/bufaux.c
+++ b/bufaux.c
@@ -12,6 +12,8 @@
  * Auxiliary functions for storing and retrieving various data types to/from
  * Buffers.
  *
+ * SSH2 packet format added by Markus Friedl
+ *
  */
 
 #include "includes.h"
@@ -82,6 +84,50 @@ buffer_get_bignum(Buffer *buffer, BIGNUM *value)
        return 2 + bytes;
 }
 
+/*
+ * Stores an BIGNUM in the buffer in SSH2 format.
+ */
+void
+buffer_put_bignum2(Buffer *buffer, BIGNUM *value)
+{
+       int bytes = BN_num_bytes(value) + 1;
+       unsigned char *buf = xmalloc(bytes);
+       int oi;
+       int hasnohigh = 0;
+       buf[0] = '\0';
+       /* Get the value of in binary */
+       oi = BN_bn2bin(value, buf+1);
+       if (oi != bytes-1)
+               fatal("buffer_put_bignum: BN_bn2bin() failed: oi %d != bin_size %d",
+                     oi, bytes);
+       hasnohigh = (buf[1] & 0x80) ? 0 : 1;
+       if (value->neg) {
+               /**XXX should be two's-complement */
+               int i, carry;
+               unsigned char *uc = buf;
+               log("negativ!");
+               for(i = bytes-1, carry = 1; i>=0; i--) {
+                       uc[i] ^= 0xff;
+                       if(carry)
+                               carry = !++uc[i];
+               }
+       }
+       buffer_put_string(buffer, buf+hasnohigh, bytes-hasnohigh);
+       memset(buf, 0, bytes);
+       xfree(buf);
+}
+
+int
+buffer_get_bignum2(Buffer *buffer, BIGNUM *value)
+{
+       /**XXX should be two's-complement */
+       int len;
+       unsigned char *bin = (unsigned char *)buffer_get_string(buffer, (unsigned int *)&len);
+       BN_bin2bn(bin, len, value);
+       xfree(bin);
+       return len;
+}
+
 /*
  * Returns an integer from the buffer (4 bytes, msb first).
  */
@@ -142,6 +188,11 @@ buffer_put_string(Buffer *buffer, const void *buf, unsigned int len)
        buffer_put_int(buffer, len);
        buffer_append(buffer, buf, len);
 }
+void 
+buffer_put_cstring(Buffer *buffer, const char *s)
+{
+       buffer_put_string(buffer, s, strlen(s));
+}
 
 /*
  * Returns a character from the buffer (0 - 255).