- markus@cvs.openbsd.org 2002/03/18 17:13:15

     [cipher.c cipher.h]
     export/import cipher states; needed by ssh-privsep

diff --git a/ChangeLog b/ChangeLog
index 060f33b9d4acfb0e50015c9c3c146a693cc22ae4..93a4241d0b5f9ee7eb440ff7c5d4ad5641d3d64c 100644 (file)
--- a/ChangeLog
+++ b/ChangeLog
@@ -44,6 +44,9 @@
    - provos@cvs.openbsd.org 2002/03/18 03:41:08
      [auth.c session.c]
      move auth_approval into getpwnamallow with help from millert@
+   - markus@cvs.openbsd.org 2002/03/18 17:13:15
+     [cipher.c cipher.h]
+     export/import cipher states; needed by ssh-privsep
 
 20020317
  - (tim) [configure.ac] Assume path given with --with-pid-dir=PATH is wanted,

diff --git a/cipher.c b/cipher.c
index 9e8f42f5e19ff9e0d8e3ca3c488992624113cdc1..7a9c9c4918340936a49fca003d0c484d1ace6023 100644 (file)
--- a/cipher.c
+++ b/cipher.c
@@ -35,7 +35,7 @@
  */
 
 #include "includes.h"
-RCSID("$OpenBSD: cipher.c,v 1.52 2002/02/18 13:05:32 markus Exp $");
+RCSID("$OpenBSD: cipher.c,v 1.53 2002/03/18 17:13:15 markus Exp $");
 
 #include "xmalloc.h"
 #include "log.h"
@@ -88,6 +88,11 @@ cipher_keylen(Cipher *c)
 {
        return (c->key_len);
 }
+u_int  
+cipher_get_number(Cipher *c)
+{
+       return (c->number);
+}
 
 u_int
 cipher_mask_ssh1(int client)
@@ -502,6 +507,174 @@ ssh_rijndael_cbc(EVP_CIPHER_CTX *ctx, u_char *dest, const u_char *src,
                for (i = blocks; i > 0; i--, cnow-=RIJNDAEL_BLOCKSIZE,
                    plain-=RIJNDAEL_BLOCKSIZE) {
                        rijndael_decrypt(&c->r_ctx, cnow, plain);
+}
+
+/* 
+ * Exports an IV from the CipherContext required to export the key
+ * state back from the unprivileged child to the privileged parent
+ * process.
+ */
+
+int
+cipher_get_keyiv_len(CipherContext *cc)
+{
+       Cipher *c = cc->cipher;
+       int ivlen;
+
+       if (c->number == SSH_CIPHER_3DES)
+               ivlen = 24;
+       else
+               ivlen = EVP_CIPHER_CTX_iv_length(&cc->evp);
+       return (ivlen);
+}
+
+void
+cipher_get_keyiv(CipherContext *cc, u_char *iv, u_int len)
+{
+       Cipher *c = cc->cipher;
+       u_char *civ = NULL;
+       int evplen;
+
+       switch (c->number) {
+       case SSH_CIPHER_SSH2:
+       case SSH_CIPHER_DES:
+       case SSH_CIPHER_BLOWFISH:
+               evplen = EVP_CIPHER_CTX_iv_length(&cc->evp);
+               if (evplen == 0)
+                       return;
+               if (evplen != len)
+                       fatal("%s: wrong iv length %d != %d", __FUNCTION__,
+                           evplen, len);
+
+               if (strncmp(c->name, "aes", 3) == 0) {
+                       struct ssh_rijndael_ctx *aesc;
+
+                       aesc = EVP_CIPHER_CTX_get_app_data(&cc->evp);
+                       if (aesc == NULL)
+                               fatal("%s: no rijndael context", __FUNCTION__);
+                       civ = aesc->r_iv;
+               } else {
+                       civ = cc->evp.iv;
+               }
+               break;
+       case SSH_CIPHER_3DES: {
+               struct ssh1_3des_ctx *desc;
+               if (len != 24)
+                       fatal("%s: bad 3des iv length: %d", __FUNCTION__, len);
+               desc = EVP_CIPHER_CTX_get_app_data(&cc->evp);
+               if (desc == NULL)
+                       fatal("%s: no 3des context", __FUNCTION__);
+               debug3("%s: Copying 3DES IV", __FUNCTION__);
+               memcpy(iv, desc->k1.iv, 8);
+               memcpy(iv + 8, desc->k2.iv, 8);
+               memcpy(iv + 16, desc->k3.iv, 8);
+               return;
+       }
+       default:
+               fatal("%s: bad cipher %d", __FUNCTION__, c->number);
+       }
+       memcpy(iv, civ, len);
+}
+
+void
+cipher_set_keyiv(CipherContext *cc, u_char *iv)
+{
+       Cipher *c = cc->cipher;
+       u_char *div = NULL;
+       int evplen = 0;
+
+       switch (c->number) {
+       case SSH_CIPHER_SSH2:
+       case SSH_CIPHER_DES:
+       case SSH_CIPHER_BLOWFISH:
+               evplen = EVP_CIPHER_CTX_iv_length(&cc->evp);
+               if (evplen == 0)
+                       return;
+
+               if (strncmp(c->name, "aes", 3) == 0) {
+                       struct ssh_rijndael_ctx *aesc;
+
+                       aesc = EVP_CIPHER_CTX_get_app_data(&cc->evp);
+                       if (aesc == NULL)
+                               fatal("%s: no rijndael context", __FUNCTION__);
+                       div = aesc->r_iv;
+               }else {
+                       div = cc->evp.iv;
+               }
+               break;
+       case SSH_CIPHER_3DES: {
+               struct ssh1_3des_ctx *desc;
+               desc = EVP_CIPHER_CTX_get_app_data(&cc->evp);
+               if (desc == NULL)
+                       fatal("%s: no 3des context", __FUNCTION__);
+               debug3("%s: Installed 3DES IV", __FUNCTION__);
+               memcpy(desc->k1.iv, iv, 8);
+               memcpy(desc->k2.iv, iv + 8, 8);
+               memcpy(desc->k3.iv, iv + 16, 8);
+               return;
+       } 
+       default:
+               fatal("%s: bad cipher %d", __FUNCTION__, c->number);
+       }
+       memcpy(div, iv, evplen);
+}
+
+#if OPENSSL_VERSION_NUMBER < 0x00907000L
+#define EVP_X_STATE(evp)       &(evp).c
+#define EVP_X_STATE_LEN(evp)   sizeof((evp).c)
+#else
+#define EVP_X_STATE(evp)       (evp).cipher_data
+#define EVP_X_STATE_LEN(evp)   (evp).cipher->ctx_size
+#endif
+
+int
+cipher_get_keycontext(CipherContext *cc, u_char *dat)
+{
+       Cipher *c = cc->cipher;
+       int plen;
+
+       if (c->number == SSH_CIPHER_3DES) {
+               struct ssh1_3des_ctx *desc;
+               desc = EVP_CIPHER_CTX_get_app_data(&cc->evp);
+               if (desc == NULL)
+                       fatal("%s: no 3des context", __FUNCTION__);
+               plen = EVP_X_STATE_LEN(desc->k1);
+               if (dat == NULL)
+                       return (3*plen);
+               memcpy(dat, EVP_X_STATE(desc->k1), plen);
+               memcpy(dat + plen, EVP_X_STATE(desc->k2), plen);
+               memcpy(dat + 2*plen, EVP_X_STATE(desc->k3), plen);
+               return (3*plen);
+       }
+
+       /* Generic EVP */
+       plen = EVP_X_STATE_LEN(cc->evp);
+       if (dat == NULL)
+               return (plen);
+
+       memcpy(dat, EVP_X_STATE(cc->evp), plen);
+       return (plen);
+}
+
+void
+cipher_set_keycontext(CipherContext *cc, u_char *dat)
+{
+       Cipher *c = cc->cipher;
+       int plen;
+
+       if (c->number == SSH_CIPHER_3DES) {
+               struct ssh1_3des_ctx *desc;
+               desc = EVP_CIPHER_CTX_get_app_data(&cc->evp);
+               if (desc == NULL)
+                       fatal("%s: no 3des context", __FUNCTION__);
+               plen = EVP_X_STATE_LEN(desc->k1);
+               memcpy(EVP_X_STATE(desc->k1), dat, plen);
+               memcpy(EVP_X_STATE(desc->k2), dat + plen, plen);
+               memcpy(EVP_X_STATE(desc->k3), dat + 2*plen, plen);
+       } else {
+               plen = EVP_X_STATE_LEN(cc->evp);
+               memcpy(EVP_X_STATE(cc->evp), dat, plen);
+       }
                        ivp = (i == 1) ? c->r_iv : cnow-RIJNDAEL_BLOCKSIZE;
                        for (j = 0; j < RIJNDAEL_BLOCKSIZE; j++)
                                plain[j] ^= ivp[j];

diff --git a/cipher.h b/cipher.h
index b3b0303c7f6079522b585d5d257462cdb6d39f04..fc7f6dd0fc46b3301938626c3a2b6d319313e28d 100644 (file)
--- a/cipher.h
+++ b/cipher.h
@@ -1,4 +1,4 @@
-/*     $OpenBSD: cipher.h,v 1.32 2002/03/04 17:27:39 stevesk Exp $     */
+/*     $OpenBSD: cipher.h,v 1.33 2002/03/18 17:13:15 markus Exp $      */
 
 /*
  * Author: Tatu Ylonen <ylo@cs.hut.fi>
@@ -81,4 +81,11 @@ void  cipher_cleanup(CipherContext *);
 void    cipher_set_key_string(CipherContext *, Cipher *, const char *, int);
 u_int   cipher_blocksize(Cipher *);
 u_int   cipher_keylen(Cipher *);
+
+u_int   cipher_get_number(Cipher *);
+void    cipher_get_keyiv(CipherContext *, u_char *, u_int);
+void    cipher_set_keyiv(CipherContext *, u_char *);
+int     cipher_get_keyiv_len(CipherContext *);
+int     cipher_get_keycontext(CipherContext *, u_char *);
+void    cipher_set_keycontext(CipherContext *, u_char *);
 #endif                         /* CIPHER_H */