Add pad support

Reviewed-by: Andy Polyakov <[email protected]> (Merged from openssl#4485)
RangerRU · Oct 12, 2017 · f4403a1 · f4403a1
1 parent 9b82c8b
commit f4403a1
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Showing 2 changed files with 20 additions and 1 deletion.
diff --git a/crypto/dh/dh_pmeth.c b/crypto/dh/dh_pmeth.c
@@ -26,6 +26,7 @@ typedef struct {
     int generator;
     int use_dsa;
     int subprime_len;
+    int pad;
     /* message digest used for parameter generation */
     const EVP_MD *md;
     int rfc5114_param;
@@ -86,6 +87,7 @@ static int pkey_dh_copy(EVP_PKEY_CTX *dst, EVP_PKEY_CTX *src)
     dctx->subprime_len = sctx->subprime_len;
     dctx->generator = sctx->generator;
     dctx->use_dsa = sctx->use_dsa;
+    dctx->pad = sctx->pad;
     dctx->md = sctx->md;
     dctx->rfc5114_param = sctx->rfc5114_param;
     dctx->param_nid = sctx->param_nid;
@@ -121,6 +123,10 @@ static int pkey_dh_ctrl(EVP_PKEY_CTX *ctx, int type, int p1, void *p2)
         dctx->subprime_len = p1;
         return 1;
 
+    case EVP_PKEY_CTRL_DH_PAD:
+        dctx->pad = p1;
+        return 1;
+
     case EVP_PKEY_CTRL_DH_PARAMGEN_GENERATOR:
         if (dctx->use_dsa)
             return -2;
@@ -255,6 +261,11 @@ static int pkey_dh_ctrl_str(EVP_PKEY_CTX *ctx,
         typ = atoi(value);
         return EVP_PKEY_CTX_set_dh_paramgen_type(ctx, typ);
     }
+    if (strcmp(type, "dh_pad") == 0) {
+        int pad;
+        pad = atoi(value);
+        return EVP_PKEY_CTX_set_dh_pad(ctx, pad);
+    }
     return -2;
 }
 
@@ -423,7 +434,10 @@ static int pkey_dh_derive(EVP_PKEY_CTX *ctx, unsigned char *key,
             *keylen = DH_size(dh);
             return 1;
         }
-        ret = DH_compute_key(key, dhpub, dh);
+        if (dctx->pad)
+            ret = DH_compute_key_padded(key, dhpub, dh);
+        else
+            ret = DH_compute_key(key, dhpub, dh);
         if (ret < 0)
             return ret;
         *keylen = ret;

diff --git a/include/openssl/dh.h b/include/openssl/dh.h
@@ -247,6 +247,10 @@ int DH_meth_set_generate_params(DH_METHOD *dhm,
                         EVP_PKEY_OP_PARAMGEN | EVP_PKEY_OP_KEYGEN, \
                         EVP_PKEY_CTRL_DH_NID, nid, NULL)
 
+# define EVP_PKEY_CTX_set_dh_pad(ctx, pad) \
+        EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DH, EVP_PKEY_OP_DERIVE, \
+                          EVP_PKEY_CTRL_DH_PAD, pad, NULL)
+
 # define EVP_PKEY_CTX_set_dh_kdf_type(ctx, kdf) \
         EVP_PKEY_CTX_ctrl(ctx, EVP_PKEY_DHX, \
                                 EVP_PKEY_OP_DERIVE, \
@@ -312,6 +316,7 @@ int DH_meth_set_generate_params(DH_METHOD *dhm,
 # define EVP_PKEY_CTRL_DH_KDF_OID                (EVP_PKEY_ALG_CTRL + 13)
 # define EVP_PKEY_CTRL_GET_DH_KDF_OID            (EVP_PKEY_ALG_CTRL + 14)
 # define EVP_PKEY_CTRL_DH_NID                    (EVP_PKEY_ALG_CTRL + 15)
+# define EVP_PKEY_CTRL_DH_PAD                    (EVP_PKEY_ALG_CTRL + 16)
 
 /* KDF types */
 # define EVP_PKEY_DH_KDF_NONE                            1