From 1ed7c908908593346bc2e3cdf37aa26a4ac200ed Mon Sep 17 00:00:00 2001
From: Andreas Schneider <mail@cynapses.org>
Date: Thu, 16 Apr 2009 14:04:19 +0000
Subject: [PATCH] Revert commit 491.

git-svn-id: svn+ssh://svn.berlios.de/svnroot/repos/libssh/trunk@492 7dcaeef0-15fb-0310-b436-a5af3365683c
---
 include/libssh/priv.h |  9 ++---
 libssh/client.c       |  7 +---
 libssh/dh.c           | 87 +++++++++++++++++--------------------------
 libssh/init.c         |  1 +
 libssh/server.c       |  4 +-
 5 files changed, 40 insertions(+), 68 deletions(-)

diff --git a/include/libssh/priv.h b/include/libssh/priv.h
index 4a4023bc..50b82f63 100644
--- a/include/libssh/priv.h
+++ b/include/libssh/priv.h
@@ -339,10 +339,6 @@ struct ssh_session {
     int dh_handshake_state;
     STRING *dh_server_signature; //information used by dh_handshake.
 
-    /* dh crypto */
-    bignum dh_g;
-    bignum dh_p;
-
     KEX server_kex;
     KEX client_kex;
     BUFFER *in_hashbuf;
@@ -524,8 +520,9 @@ void dh_generate_x(SSH_SESSION *session);
 void dh_generate_y(SSH_SESSION *session);
 void dh_generate_f(SSH_SESSION *session);
 
-int ssh_crypto_init(SSH_SESSION *session);
-void ssh_crypto_finalize(SSH_SESSION *session);
+/* FIXME: replace me with a thread safe function */
+void ssh_crypto_init(void);
+void ssh_crypto_finalize(void);
 
 STRING *dh_get_e(SSH_SESSION *session);
 STRING *dh_get_f(SSH_SESSION *session);
diff --git a/libssh/client.c b/libssh/client.c
index 26277f03..09f522ae 100644
--- a/libssh/client.c
+++ b/libssh/client.c
@@ -449,11 +449,7 @@ int ssh_connect(SSH_SESSION *session) {
   session->alive = 0;
   session->client = 1;
 
-  if (ssh_crypto_init(session) < 0) {
-    ssh_set_error(session, SSH_FATAL, "Initializing crypto functions failed");
-    leave_function();
-    return SSH_ERROR;
-  }
+  ssh_crypto_init();
   ssh_socket_init();
 
   if (options->fd == -1 && options->host == NULL) {
@@ -632,7 +628,6 @@ void ssh_disconnect(SSH_SESSION *session) {
 
 error:
   leave_function();
-  ssh_crypto_finalize(session);
   ssh_cleanup(session);
 }
 
diff --git a/libssh/dh.c b/libssh/dh.c
index 93bd090b..1d825b2e 100644
--- a/libssh/dh.c
+++ b/libssh/dh.c
@@ -69,6 +69,9 @@ static unsigned char p_value[] = {
 #define P_LEN 128	/* Size in bytes of the p number */
 
 static unsigned long g_int = 2 ;	/* G is defined as 2 by the ssh2 standards */
+static bignum g;
+static bignum p;
+static int ssh_crypto_inited=0;
 
 int ssh_get_random(void *where, int len, int strong){
 
@@ -93,51 +96,37 @@ int ssh_get_random(void *where, int len, int strong){
 
 
 /* it inits the values g and p which are used for DH key agreement */
-int ssh_crypto_init(struct ssh_session *session) {
+void ssh_crypto_init(void){
+    if(ssh_crypto_inited == 0){
 #ifdef HAVE_LIBGCRYPT
-  gcry_check_version(NULL);
-
-  if (!gcry_control(GCRYCTL_INITIALIZATION_FINISHED_P,0)) {
-    gcry_control(GCRYCTL_INIT_SECMEM, 4096);
-    gcry_control(GCRYCTL_INITIALIZATION_FINISHED,0);
-  }
+        gcry_check_version(NULL);
+	if (!gcry_control(GCRYCTL_INITIALIZATION_FINISHED_P,0))
+	{
+	  gcry_control(GCRYCTL_INIT_SECMEM, 4096);
+	  gcry_control(GCRYCTL_INITIALIZATION_FINISHED,0);
+	}
 #endif
-
-  session->dh_g = bignum_new();
-  if (session->dh_g == NULL) {
-    return -1;
-  }
-  bignum_set_word(session->dh_g, g_int);
-
+        g=bignum_new();
+        bignum_set_word(g,g_int);
 #ifdef HAVE_LIBGCRYPT
-  bignum_bin2bn(p_value, P_LEN, &session->dh_p);
-  if (session->dh_p == NULL) {
-    bignum_free(session->dh_g);
-    session->dh_g = NULL;
-    return -1;
-  }
+        bignum_bin2bn(p_value,P_LEN,&p);
 #elif defined HAVE_LIBCRYPTO
-  session->dh_p = bignum_new();
-  if (session->dh_p == NULL) {
-    bignum_free(session->dh_g);
-    session->dh_g = NULL;
-    return -1;
-  }
-  bignum_bin2bn(p_value, P_LEN, session->dh_p);
-  OpenSSL_add_all_algorithms();
+        p=bignum_new();
+        bignum_bin2bn(p_value,P_LEN,p);
+        OpenSSL_add_all_algorithms();
 #endif
-
-  return 0;
+        ssh_crypto_inited++;
+    }
 }
 
-void ssh_crypto_finalize(struct ssh_session *session) {
-  bignum_free(session->dh_g);
-  session->dh_g = NULL;
-
-  bignum_free(session->dh_p);
-  session->dh_p = NULL;
+void ssh_crypto_finalize(void){
+    if(ssh_crypto_inited){
+        bignum_free(g);
+        bignum_free(p);
+        ssh_crypto_inited=0;
+    }
 }
-
+   
 /* prints the bignum on stderr */
 void ssh_print_bignum(const char *which,bignum num){
 #ifdef HAVE_LIBGCRYPT
@@ -234,11 +223,9 @@ void dh_generate_e(SSH_SESSION *session){
 #endif
     session->next_crypto->e=bignum_new();
 #ifdef HAVE_LIBGCRYPT
-    bignum_mod_exp(session->next_crypto->e, session->dh_g,
-        session->next_crypto->x, session->dh_p);
+    bignum_mod_exp(session->next_crypto->e,g,session->next_crypto->x,p);
 #elif defined HAVE_LIBCRYPTO
-    bignum_mod_exp(session->next_crypto->e, session->dh_g,
-        session->next_crypto->x, session->dh_p, ctx);
+    bignum_mod_exp(session->next_crypto->e,g,session->next_crypto->x,p,ctx);
 #endif
 #ifdef DEBUG_CRYPTO
     ssh_print_bignum("e",session->next_crypto->e);
@@ -254,11 +241,9 @@ void dh_generate_f(SSH_SESSION *session){
 #endif
     session->next_crypto->f=bignum_new();
 #ifdef HAVE_LIBGCRYPT
-    bignum_mod_exp(session->next_crypto->f, session->dh_g,
-        session->next_crypto->y, session->dh_p);
+    bignum_mod_exp(session->next_crypto->f,g,session->next_crypto->y,p);
 #elif defined HAVE_LIBCRYPTO
-    bignum_mod_exp(session->next_crypto->f, session->dh_g,
-        session->next_crypto->y, session->dh_p, ctx);
+    bignum_mod_exp(session->next_crypto->f,g,session->next_crypto->y,p,ctx);
 #endif
 #ifdef DEBUG_CRYPTO
     ssh_print_bignum("f",session->next_crypto->f);
@@ -342,19 +327,15 @@ void dh_build_k(SSH_SESSION *session){
     /* the server and clients don't use the same numbers */
 #ifdef HAVE_LIBGCRYPT
     if(session->client){
-        bignum_mod_exp(session->next_crypto->k, session->next_crypto->f,
-            session->next_crypto->x, session->dh_p);
+        bignum_mod_exp(session->next_crypto->k,session->next_crypto->f,session->next_crypto->x,p);
     } else {
-        bignum_mod_exp(session->next_crypto->k, session->next_crypto->e,
-            session->next_crypto->y, session->dh_p);
+        bignum_mod_exp(session->next_crypto->k,session->next_crypto->e,session->next_crypto->y,p);
     }
 #elif defined HAVE_LIBCRYPTO
     if(session->client){
-        bignum_mod_exp(session->next_crypto->k, session->next_crypto->f,
-            session->next_crypto->x, session->dh_p, ctx);
+        bignum_mod_exp(session->next_crypto->k,session->next_crypto->f,session->next_crypto->x,p,ctx);
     } else {
-        bignum_mod_exp(session->next_crypto->k, session->next_crypto->e,
-            session->next_crypto->y, session->dh_p, ctx);
+        bignum_mod_exp(session->next_crypto->k,session->next_crypto->e,session->next_crypto->y,p,ctx);
     }
 #endif
 #ifdef DEBUG_CRYPTO
diff --git a/libssh/init.c b/libssh/init.c
index e9c05393..6b10033b 100644
--- a/libssh/init.c
+++ b/libssh/init.c
@@ -38,6 +38,7 @@
  */
 int ssh_finalize(void)
 {
+  ssh_crypto_finalize();
 #ifdef HAVE_LIBGCRYPT
   gcry_control(GCRYCTL_TERM_SECMEM);
 #elif defined HAVE_LIBCRYPTO
diff --git a/libssh/server.c b/libssh/server.c
index 7193a285..358b13e7 100644
--- a/libssh/server.c
+++ b/libssh/server.c
@@ -332,9 +332,7 @@ static int dh_handshake_server(SSH_SESSION *session){
 /* do the banner and key exchange */
 int ssh_accept(SSH_SESSION *session){
     ssh_send_banner(session,1);
-    if (ssh_crypto_init(session) < 0) {
-      return -1;
-    }
+    ssh_crypto_init();
     session->alive=1;
     session->clientbanner=ssh_get_banner(session);
     if (server_set_kex(session) < 0) {