Squashed commit of PIPE_CONNECT

[exim.git] / src / src / pdkim / pdkim.c

diff --git a/src/src/pdkim/pdkim.c b/src/src/pdkim/pdkim.c
index 381bdbc5dba15493d7fccfa9ddb72b9d39311ef7..594af03c526c028b0065be196984db6878623d74 100644 (file)
--- a/src/src/pdkim/pdkim.c
+++ b/src/src/pdkim/pdkim.c
@@ -80,7 +80,7 @@ const pdkim_hashtype pdkim_hashes[] = {
 const uschar * pdkim_keytypes[] = {
   [KEYTYPE_RSA] =      US"rsa",
 #ifdef SIGN_HAVE_ED25519
-  [KEYTYPE_ED25519] =  US"ed25519",            /* Works for 3.6.0 GnuTLS */
+  [KEYTYPE_ED25519] =  US"ed25519",            /* Works for 3.6.0 GnuTLS, OpenSSL 1.1.1 */
 #endif
 
 #ifdef notyet_EC_dkim_extensions       /* https://tools.ietf.org/html/draft-srose-dkim-ecc-00 */
@@ -192,6 +192,7 @@ switch(status)
   case PDKIM_ERR_RSA_SIGNING:  return US"SIGNING";
   case PDKIM_ERR_LONG_LINE:    return US"LONG_LINE";
   case PDKIM_ERR_BUFFER_TOO_SMALL:     return US"BUFFER_TOO_SMALL";
+  case PDKIM_ERR_EXCESS_SIGS:  return US"EXCESS_SIGS";
   case PDKIM_SIGN_PRIVKEY_WRAP:        return US"PRIVKEY_WRAP";
   case PDKIM_SIGN_PRIVKEY_B64D:        return US"PRIVKEY_B64D";
   default: return US"(unknown)";
@@ -792,7 +793,7 @@ pdkim_signature * sig;
 
 for (b = ctx->bodyhash; b; b = b->next)                /* Finish hashes */
   {
-  DEBUG(D_acl) debug_printf("PDKIM: finish bodyhash %d/%d/%d len %ld\n",
+  DEBUG(D_acl) debug_printf("PDKIM: finish bodyhash %d/%d/%ld len %ld\n",
            b->hashtype, b->canon_method, b->bodylength, b->signed_body_bytes);
   exim_sha_finish(&b->body_hash_ctx, &b->bh);
   }
@@ -1008,6 +1009,13 @@ else
       while (last_sig->next) last_sig = last_sig->next;
       last_sig->next = sig;
       }
+
+    if (--dkim_collect_input == 0)
+      {
+      ctx->headers = pdkim_prepend_stringlist(ctx->headers, ctx->cur_header->s);
+      ctx->cur_header->s[ctx->cur_header->ptr = 0] = '\0';
+      return PDKIM_ERR_EXCESS_SIGS;
+      }
     }
 
   /* all headers are stored for signature verification */
@@ -1033,7 +1041,7 @@ int p, rc;
 if (!data)
   pdkim_body_complete(ctx);
 
-else for (p = 0; p<len; p++)
+else for (p = 0; p < len; p++)
   {
   uschar c = data[p];
 
@@ -1336,6 +1344,28 @@ return string_from_gstring(hdr);
 
 /* -------------------------------------------------------------------------- */
 
+/* According to draft-ietf-dcrup-dkim-crypto-07 "keys are 256 bits" (referring
+to DNS, hence the pubkey).  Check for more than 32 bytes; if so assume the
+alternate possible representation (still) being discussed: a
+SubjectPublickeyInfo wrapped key - and drop all but the trailing 32-bytes (it
+should be a DER, with exactly 12 leading bytes - but we could accept a BER also,
+which could be any size).  We still rely on the crypto library for checking for
+undersize.
+
+When the RFC is published this should be re-addressed. */
+
+static void
+check_bare_ed25519_pubkey(pdkim_pubkey * p)
+{
+int excess = p->key.len - 32;
+if (excess > 0)
+  {
+  DEBUG(D_acl) debug_printf("PDKIM: unexpected pubkey len %lu\n", p->key.len);
+  p->key.data += excess; p->key.len = 32;
+  }
+}
+
+
 static pdkim_pubkey *
 pdkim_key_from_dns(pdkim_ctx * ctx, pdkim_signature * sig, ev_ctx * vctx,
   const uschar ** errstr)
@@ -1408,6 +1438,9 @@ if (sig->keytype < 0)
   }
 k_ok:
 
+if (sig->keytype == KEYTYPE_ED25519)
+  check_bare_ed25519_pubkey(p);
+
 if ((*errstr = exim_dkim_verify_init(&p->key,
            sig->keytype == KEYTYPE_ED25519 ? KEYFMT_ED25519_BARE : KEYFMT_DER,
            vctx)))
@@ -1734,11 +1767,19 @@ for (sig = ctx->sig; sig; sig = sig->next)
       sig->verify_ext_status = PDKIM_VERIFY_INVALID_SIGNATURE_ERROR;
 
       DEBUG(D_acl) debug_printf(
-         " Error in DKIM-Signature header: tags missing or invalid\n"
-         "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n");
+         " Error in DKIM-Signature header: tags missing or invalid (%s)\n"
+         "PDKIM <<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<<\n",
+         !(sig->domain && *sig->domain) ? "d="
+         : !(sig->selector && *sig->selector) ? "s="
+         : !(sig->headernames && *sig->headernames) ? "h="
+         : !sig->bodyhash.data ? "bh="
+         : !sig->sighash.data ? "b="
+         : sig->keytype < 0 || sig->hashtype < 0 ? "a="
+         : "v="
+         );
       goto NEXT_VERIFY;
       }
-
+ 
     /* Make sure sig uses supported DKIM version (only v1) */
     if (sig->version != 1)
       {