SSH 2 support, phase 1, debugging. Currently does Diffie-Hellman and gets

the same results as the server, which is a pretty good start.

[originally from svn r569]

ssh.h

@@ -1,10 +1,23 @@
 #include <string.h>
 
+/*
+ * Useful thing.
+ */
+#ifndef lenof
+#define lenof(x) ( (sizeof((x))) / (sizeof(*(x))))
+#endif
+
 #define SSH_CIPHER_IDEA		1
 #define SSH_CIPHER_DES		2
 #define SSH_CIPHER_3DES		3
 #define SSH_CIPHER_BLOWFISH	6
 
+#ifdef MSCRYPTOAPI
+#define APIEXTRA 8
+#else
+#define APIEXTRA 0
+#endif
+
 struct RSAKey {
     int bits;
     int bytes;
@@ -48,10 +61,43 @@ void MD5Update(struct MD5Context *context, unsigned char const *buf,
                unsigned len);
 void MD5Final(unsigned char digest[16], struct MD5Context *context);
 
+typedef struct {
+    uint32 h[5];
+    unsigned char block[64];
+    int blkused;
+    uint32 lenhi, lenlo;
+} SHA_State;
+
+void SHA_Init(SHA_State *s);
+void SHA_Bytes(SHA_State *s, void *p, int len);
+void SHA_Final(SHA_State *s, unsigned char *output);
+
 struct ssh_cipher {
     void (*sesskey)(unsigned char *key);
     void (*encrypt)(unsigned char *blk, int len);
     void (*decrypt)(unsigned char *blk, int len);
+    char *name;
+    int blksize;
+};
+
+struct ssh_mac {
+    void (*sesskey)(unsigned char *key, int len);
+    void (*generate)(unsigned char *blk, int len, unsigned long seq);
+    int (*verify)(unsigned char *blk, int len, unsigned long seq);
+    char *name;
+    int len;
+};
+
+struct ssh_kex {
+    char *name;
+};
+
+struct ssh_hostkey {
+    char *name;
+};
+
+struct ssh_compress {
+    char *name;
 };
 
 #ifndef MSCRYPTOAPI
@@ -62,3 +108,17 @@ int random_byte(void);
 void random_add_noise(void *noise, int length);
 
 void logevent (char *);
+
+/*
+ * A Bignum is stored as a sequence of `unsigned short' words. The
+ * first tells how many remain; the remaining ones are digits, LS
+ * first.
+ */
+typedef unsigned short *Bignum;
+
+Bignum newbn(int length);
+void freebn(Bignum b);
+void modpow(Bignum base, Bignum exp, Bignum mod, Bignum result);
+
+Bignum dh_create_e(void);
+Bignum dh_find_K(Bignum f);