[PATCH 7/8] g10: add cleartext parameter to receive_seckey_from_agent()

[Daniel Kahn Gillmor]

* g10/export.c, g10/main.h (receive_seckey_from_agent): add cleartext
  parameter, enabling retrieval of the secret key, unlocked.
* g10/export.c (do_export_stream): send cleartext as 0
* g10/keygen.c (card_store_key_with_backup): use cleartext=0 to ensure
  that smartcard backups are all passphrase-locked.
---
 g10/export.c | 15 ++++++++++++---
 g10/keygen.c |  2 +-
 g10/main.h   |  1 +
 3 files changed, 14 insertions(+), 4 deletions(-)

diff --git a/g10/export.c b/g10/export.c
index 695bbef..54c72a2 100644
--- a/g10/export.c
+++ b/g10/export.c
@@ -1042,10 +1042,15 @@ print_status_exported (PKT_public_key *pk)
  * Then, parse the decrypted key data in transfer format, and put
  * secret papameters into PK.
  *
+ * if CLEARTEXT is 0, store the secret key material
+ * passphrase-protected.  otherwise, store secret key material in the
+ * clear.
+ *
  * CACHE_NONCE_ADDR is used to share nonce for multple key retrievals.
  */
 gpg_error_t
 receive_seckey_from_agent (ctrl_t ctrl, gcry_cipher_hd_t cipherhd,
+                           int cleartext,
                            char **cache_nonce_addr, const char *hexgrip,
                            PKT_public_key *pk)
 {
@@ -1061,7 +1066,7 @@ receive_seckey_from_agent (ctrl_t ctrl, gcry_cipher_hd_t cipherhd,
     log_info ("key %s: asking agent for the secret parts\n", hexgrip);
 
   prompt = gpg_format_keydesc (pk, FORMAT_KEYDESC_EXPORT,1);
-  err = agent_export_key (ctrl, hexgrip, prompt, 1, cache_nonce_addr,
+  err = agent_export_key (ctrl, hexgrip, prompt, !cleartext, cache_nonce_addr,
                           &wrappedkey, &wrappedkeylen);
   xfree (prompt);
 
@@ -1089,7 +1094,10 @@ receive_seckey_from_agent (ctrl_t ctrl, gcry_cipher_hd_t cipherhd,
   err = gcry_sexp_sscan (&s_skey, NULL, key, realkeylen);
   if (!err)
     {
-      err = transfer_format_to_openpgp (s_skey, pk);
+      if (cleartext)
+        err = cleartext_secret_key_to_openpgp (s_skey, pk);
+      else
+        err = transfer_format_to_openpgp (s_skey, pk);
       gcry_sexp_release (s_skey);
     }
 
@@ -1485,7 +1493,8 @@ do_export_stream (ctrl_t ctrl, iobuf_t out, strlist_t users, int secret,
                 }
               else if (!err)
                 {
-                  err = receive_seckey_from_agent (ctrl, cipherhd, &cache_nonce,
+                  err = receive_seckey_from_agent (ctrl, cipherhd,
+                                                   0, &cache_nonce,
                                                    hexgrip, pk);
                   if (err)
                     {
diff --git a/g10/keygen.c b/g10/keygen.c
index 7a07109..83962c2 100644
--- a/g10/keygen.c
+++ b/g10/keygen.c
@@ -3957,7 +3957,7 @@ card_store_key_with_backup (ctrl_t ctrl, PKT_public_key *sub_psk,
       goto leave;
     }
 
-  err = receive_seckey_from_agent (ctrl, cipherhd, &cache_nonce, hexgrip, sk);
+  err = receive_seckey_from_agent (ctrl, cipherhd, 0, &cache_nonce, hexgrip, sk);
   if (err)
     {
       log_error ("error getting secret key from agent: %s\n", gpg_strerror (err));
diff --git a/g10/main.h b/g10/main.h
index 5b5947e..99ba164 100644
--- a/g10/main.h
+++ b/g10/main.h
@@ -383,6 +383,7 @@ gpg_error_t export_pubkey_buffer (ctrl_t ctrl, const char *keyspec,
                                   void **r_data, size_t *r_datalen);
 
 gpg_error_t receive_seckey_from_agent (ctrl_t ctrl, gcry_cipher_hd_t cipherhd,
+                                       int cleartext,
                                        char **cache_nonce_addr, const char *hexgrip,
                                        PKT_public_key *pk);
 
-- 
2.8.1