Public Keys are being exported to SubjectPublicKeyInfo format, instead of custom formats. For RSA keys the PKCS #1 format can be used as well.

1 files changed, 31 insertions, 10 deletions

diff --git a/libtomcrypt/pk/dsa/dsa_export.c b/libtomcrypt/pk/dsa/dsa_export.c
index 11b6638..1fef6c7 100644
--- a/libtomcrypt/pk/dsa/dsa_export.c
+++ b/libtomcrypt/pk/dsa/dsa_export.c
@@ -27,8 +27,8 @@
 */
 int dsa_export(unsigned char *out, unsigned long *outlen, int type, dsa_key *key)
 {
-   unsigned char flags[1];
    unsigned long zero=0;
+   int err;
 
    LTC_ARGCHK(out    != NULL);
    LTC_ARGCHK(outlen != NULL);
@@ -43,8 +43,6 @@ int dsa_export(unsigned char *out, unsigned long *outlen, int type, dsa_key *key
       return CRYPT_INVALID_ARG;
    }
 
-   flags[0] = (type != PK_PUBLIC) ? 1 : 0;
-
    /* This encoding is different from the one in original
     * libtomcrypt. It uses a compatible encoding with gnutls
     * and openssl 
@@ -59,13 +57,36 @@ int dsa_export(unsigned char *out, unsigned long *outlen, int type, dsa_key *key
                           LTC_ASN1_INTEGER,      1UL, &key->x,
                           LTC_ASN1_EOL,          0UL, NULL);
    } else {
-      return der_encode_sequence_multi(out, outlen,
-                                 LTC_ASN1_BIT_STRING,   1UL, flags,
-                                 LTC_ASN1_INTEGER,      1UL, &key->g,
-                                 LTC_ASN1_INTEGER,      1UL, &key->p,
-                                 LTC_ASN1_INTEGER,      1UL, &key->q,
-                                 LTC_ASN1_INTEGER,      1UL, &key->y,
-                                 LTC_ASN1_EOL,          0UL, NULL);
+      unsigned long tmplen = (mp_count_bits(&key->y)/8)+8;
+      unsigned char* tmp = XMALLOC(tmplen);
+      ltc_asn1_list int_list[3];
+   
+      if (tmp == NULL) {
+	   return CRYPT_MEM;
+      }
+      
+      err = der_encode_integer(&key->y, tmp, &tmplen);
+      if (err != CRYPT_OK) {
+		  goto error;
+      }
+
+      int_list[0].data = &key->p;
+      int_list[0].size = 1UL;
+      int_list[0].type = LTC_ASN1_INTEGER;
+      int_list[1].data = &key->q;
+      int_list[1].size = 1UL;
+      int_list[1].type = LTC_ASN1_INTEGER;
+      int_list[2].data = &key->g;
+      int_list[2].size = 1UL;
+      int_list[2].type = LTC_ASN1_INTEGER;
+
+      err = der_encode_subject_public_key_info(out, outlen, 
+        PKA_DSA, tmp, tmplen, 
+        LTC_ASN1_SEQUENCE, int_list, sizeof(int_list)/sizeof(int_list[0]));
+      
+error:
+      XFREE(tmp);
+      return err;
    }
 }