gpg: Move all DNS access to Dirmngr.

* common/dns-cert.h: Move to ../dirmngr/.
* common/dns-cert.c: Move to ../dirmngr/.  Change args to return the
key as a buffer.
* common/t-dns-cert.c: Move to ../dirmngr/.
* common/pka.c, common/pka.h, common/t-pka.c: Remove.

* dirmngr/server.c (data_line_cookie_write): Factor code out to
data_line_write and make it a wrapper for that.
(data_line_write): New.
(cmd_dns_cert): New.
(register_commands): Register new command.

* g10/Makefile.am (LDADD): Remove DNSLIBS.
* g10/call-dirmngr.c (dns_cert_parm_s): New.
(dns_cert_data_cb, dns_cert_status_cb): New.
(gpg_dirmngr_dns_cert): New.
(gpg_dirmngr_get_pka): New.
* g10/gpgv.c (gpg_dirmngr_get_pka): New dummy function.
* g10/keyserver.c (keyserver_import_cert): Replace get_dns_cert by
gpg_dirmngr_dns_cert.
(keyserver_import_pka): Replace get_pka_info by gpg_dirmngr_get_pka.
* g10/mainproc.c: Include call-dirmngr.h.
(pka_uri_from_sig): Add CTX arg. Replace get_pka_info by
gpg_dirmngr_get_pka.
--

With this patch gpg does not do any network access itself but uses
dirmngr for that.  Note that we need to keep linking to NETLIBS due to
the logging code and because we need TCP for our socket emulation
under Windows.  Probably also required for Solaris etc.

Signed-off-by: Werner Koch <[email protected]>

1 files changed, 235 insertions, 0 deletions

diff --git a/g10/call-dirmngr.c b/g10/call-dirmngr.c
index bb571b2e9..e452c971e 100644
--- a/g10/call-dirmngr.c
+++ b/g10/call-dirmngr.c
@@ -78,6 +78,16 @@ struct ks_put_parm_s
 };
 
 
+/* Parameter structure used with the DNS_CERT command.  */
+struct dns_cert_parm_s
+{
+  estream_t memfp;
+  unsigned char *fpr;
+  size_t fprlen;
+  char *url;
+};
+
+
 /* Data used to associate an session with dirmngr contexts.  We can't
    use a simple one to one mapping because we sometimes need two
    connections to the dirmngr; for example while doing a listing and
@@ -957,3 +967,228 @@ gpg_dirmngr_ks_put (ctrl_t ctrl, void *data, size_t datalen, kbnode_t keyblock)
   close_context (ctrl, ctx);
   return err;
 }
+
+
+
+/* Data callback for the DNS_CERT command. */
+static gpg_error_t
+dns_cert_data_cb (void *opaque, const void *data, size_t datalen)
+{
+  struct dns_cert_parm_s *parm = opaque;
+  gpg_error_t err = 0;
+  size_t nwritten;
+
+  if (!data)
+    return 0;  /* Ignore END commands.  */
+  if (!parm->memfp)
+    return 0;  /* Data is not required.  */
+
+  if (es_write (parm->memfp, data, datalen, &nwritten))
+    err = gpg_error_from_syserror ();
+
+  return err;
+}
+
+
+/* Status callback for the DNS_CERT command.  */
+static gpg_error_t
+dns_cert_status_cb (void *opaque, const char *line)
+{
+  struct dns_cert_parm_s *parm = opaque;
+  gpg_error_t err = 0;
+  const char *s;
+  size_t nbytes;
+
+  if ((s = has_leading_keyword (line, "FPR")))
+    {
+      char *buf;
+
+      if (!(buf = xtrystrdup (s)))
+        err = gpg_error_from_syserror ();
+      else if (parm->fpr)
+        err = gpg_error (GPG_ERR_DUP_KEY);
+      else if (!hex2str (buf, buf, strlen (buf)+1, &nbytes))
+        err = gpg_error_from_syserror ();
+      else if (nbytes < 20)
+        err = gpg_error (GPG_ERR_TOO_SHORT);
+      else
+        {
+          parm->fpr = xtrymalloc (nbytes);
+          if (!parm->fpr)
+            err = gpg_error_from_syserror ();
+          else
+            memcpy (parm->fpr, buf, (parm->fprlen = nbytes));
+        }
+      xfree (buf);
+    }
+  else if ((s = has_leading_keyword (line, "URL")) && *s)
+    {
+      if (parm->url)
+        err = gpg_error (GPG_ERR_DUP_KEY);
+      else if (!(parm->fpr = xtrymalloc (nbytes)))
+        err = gpg_error_from_syserror ();
+      else
+        memcpy (parm->fpr, line, (parm->fprlen = nbytes));
+    }
+
+  return err;
+}
+
+/* Ask the dirmngr for a DNS CERT record.  Depending on the found
+   subtypes different return values are set:
+
+   - For a PGP subtype a new estream with that key will be returned at
+     R_KEY and the other return parameters are set to NULL/0.
+
+   - For an IPGP subtype the fingerprint is stored as a malloced block
+     at (R_FPR,R_FPRLEN).  If an URL is available it is stored as a
+     malloced string at R_URL; NULL is stored if there is no URL.
+
+   If CERTTYPE is DNS_CERTTYPE_ANY this function returns the first
+   CERT record found with a supported type; it is expected that only
+   one CERT record is used.  If CERTTYPE is one of the supported
+   certtypes, only records with this certtype are considered and the
+   first one found is returned.  All R_* args are optional. */
+gpg_error_t
+gpg_dirmngr_dns_cert (ctrl_t ctrl, const char *name, const char *certtype,
+                      estream_t *r_key,
+                      unsigned char **r_fpr, size_t *r_fprlen,
+                      char **r_url)
+{
+  gpg_error_t err;
+  assuan_context_t ctx;
+  struct dns_cert_parm_s parm;
+  char *line = NULL;
+
+  memset (&parm, 0, sizeof parm);
+  if (r_key)
+    *r_key = NULL;
+  if (r_fpr)
+    *r_fpr = NULL;
+  if (r_fprlen)
+    *r_fprlen = 0;
+  if (r_url)
+    *r_url = NULL;
+
+  err = open_context (ctrl, &ctx);
+  if (err)
+    return err;
+
+  line = es_bsprintf ("DNS_CERT %s %s", certtype, name);
+  if (!line)
+    {
+      err = gpg_error_from_syserror ();
+      goto leave;
+    }
+  if (strlen (line) + 2 >= ASSUAN_LINELENGTH)
+    {
+      err = gpg_error (GPG_ERR_TOO_LARGE);
+      goto leave;
+    }
+
+  parm.memfp = es_fopenmem (0, "rwb");
+  if (!parm.memfp)
+    {
+      err = gpg_error_from_syserror ();
+      goto leave;
+    }
+  err = assuan_transact (ctx, line, dns_cert_data_cb, &parm,
+                         NULL, NULL, dns_cert_status_cb, &parm);
+  if (err)
+    goto leave;
+
+  if (r_key)
+    {
+      es_rewind (parm.memfp);
+      *r_key = parm.memfp;
+      parm.memfp = NULL;
+    }
+
+  if (r_fpr && parm.fpr)
+    {
+      *r_fpr = parm.fpr;
+      parm.fpr = NULL;
+    }
+  if (r_fprlen)
+    *r_fprlen = parm.fprlen;
+
+  if (r_url && parm.url)
+    {
+      *r_url = parm.url;
+      parm.url = NULL;
+    }
+
+ leave:
+  xfree (parm.fpr);
+  xfree (parm.url);
+  es_fclose (parm.memfp);
+  xfree (line);
+  close_context (ctrl, ctx);
+  return err;
+}
+
+
+/* Ask the dirmngr for PKA info.  On success the retrieved fingerprint
+   is returned in a malloced buffer at R_FPR and its length is stored
+   at R_FPRLEN.  If an URL is available it is stored as a malloced
+   string at R_URL.  On error all return values are set to NULL/0.  */
+gpg_error_t
+gpg_dirmngr_get_pka (ctrl_t ctrl, const char *userid,
+                     unsigned char **r_fpr, size_t *r_fprlen,
+                     char **r_url)
+{
+  gpg_error_t err;
+  assuan_context_t ctx;
+  struct dns_cert_parm_s parm;
+  char *line = NULL;
+
+  memset (&parm, 0, sizeof parm);
+  if (r_fpr)
+    *r_fpr = NULL;
+  if (r_fprlen)
+    *r_fprlen = 0;
+  if (r_url)
+    *r_url = NULL;
+
+  err = open_context (ctrl, &ctx);
+  if (err)
+    return err;
+
+  line = es_bsprintf ("DNS_CERT --pka -- %s", userid);
+  if (!line)
+    {
+      err = gpg_error_from_syserror ();
+      goto leave;
+    }
+  if (strlen (line) + 2 >= ASSUAN_LINELENGTH)
+    {
+      err = gpg_error (GPG_ERR_TOO_LARGE);
+      goto leave;
+    }
+
+  err = assuan_transact (ctx, line, dns_cert_data_cb, &parm,
+                         NULL, NULL, dns_cert_status_cb, &parm);
+  if (err)
+    goto leave;
+
+  if (r_fpr && parm.fpr)
+    {
+      *r_fpr = parm.fpr;
+      parm.fpr = NULL;
+    }
+  if (r_fprlen)
+    *r_fprlen = parm.fprlen;
+
+  if (r_url && parm.url)
+    {
+      *r_url = parm.url;
+      parm.url = NULL;
+    }
+
+ leave:
+  xfree (parm.fpr);
+  xfree (parm.url);
+  xfree (line);
+  close_context (ctrl, ctx);
+  return err;
+}