pki: Add ecdsa support for signature_to_blob.

include/libssh/pki.h

@@ -22,6 +22,13 @@
 #ifndef PKI_H_
 #define PKI_H_
 
+#ifdef HAVE_OPENSSL_EC_H
+#include <openssl/ec.h>
+#endif
+#ifdef HAVE_OPENSSL_ECDSA_H
+#include <openssl/ecdsa.h>
+#endif
+
 #include "libssh/crypto.h"
 
 #define SSH_KEY_FLAG_EMPTY   0x0
@@ -54,11 +61,16 @@ struct ssh_signature_struct {
 #ifdef HAVE_LIBGCRYPT
     gcry_sexp_t dsa_sig;
     gcry_sexp_t rsa_sig;
+    void *ecdsa_sig;
 #elif defined HAVE_LIBCRYPTO
     DSA_SIG *dsa_sig;
     ssh_string rsa_sig;
+# ifdef HAVE_OPENSSL_ECC
+    ECDSA_SIG *ecdsa_sig;
+# else
+    void *ecdsa_sig;
+# endif
 #endif
-    void *ecdsa;
 };
 
 typedef struct ssh_signature_struct *ssh_signature;

src/pki_crypto.c

@@ -1003,6 +1003,35 @@ ssh_string pki_signature_to_blob(const ssh_signature sig)
             sig_blob = ssh_string_copy(sig->rsa_sig);
             break;
         case SSH_KEYTYPE_ECDSA:
+#ifdef HAVE_OPENSSL_ECC
+            r = make_bignum_string(sig->ecdsa_sig->r);
+            if (r == NULL) {
+                return NULL;
+            }
+            s = make_bignum_string(sig->ecdsa_sig->s);
+            if (s == NULL) {
+                ssh_string_free(r);
+                return NULL;
+            }
+
+            memcpy(buffer,
+                   ((char *)ssh_string_data(r)) + ssh_string_len(r) - 20,
+                   20);
+            memcpy(buffer + 20,
+                   ((char *)ssh_string_data(s)) + ssh_string_len(s) - 20,
+                   20);
+
+            ssh_string_free(r);
+            ssh_string_free(s);
+
+            sig_blob = ssh_string_new(40);
+            if (sig_blob == NULL) {
+                return NULL;
+            }
+
+            ssh_string_fill(sig_blob, buffer, 40);
+            break;
+#endif
         case SSH_KEYTYPE_UNKNOWN:
             ssh_pki_log("Unknown signature key type: %d", sig->type);
             return NULL;