DKIM: fix errorcheck in signing, lilbgcrypt version. Bug 2450

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

diff --git a/src/src/pdkim/signing.c b/src/src/pdkim/signing.c
index d7491565f97d89b083e5e8c8598f9ebcc3abd1be..102e7bf5152738128eb6ac4b8b68df07e6ccecd9 100644 (file)
--- a/src/src/pdkim/signing.c
+++ b/src/src/pdkim/signing.c
@@ -28,8 +28,8 @@ features_crypto(void)
 
 #ifndef DISABLE_DKIM   /* rest of file */
 
-#ifndef SUPPORT_TLS
-# error Need SUPPORT_TLS for DKIM
+#ifdef DISABLE_TLS
+# error Must no DISABLE_TLS, for DKIM
 #endif
 
 
@@ -412,8 +412,9 @@ if (  !(s1 = Ustrstr(CS privkey_pem, "-----BEGIN RSA PRIVATE KEY-----"))
 
 *s2 = '\0';
 
-if ((der.len = b64decode(s1, &der.data)) < 0)
+if ((rc = b64decode(s1, &der.data) < 0))
   return US"Bad PEM-DER b64 decode";
+der.len = rc;
 
 /* untangle asn.1 */
 
@@ -499,7 +500,7 @@ switch (hash)
   }
 
 #define SIGSPACE 128
-sig->data = store_get(SIGSPACE);
+sig->data = store_get(SIGSPACE, FALSE);
 
 if (gcry_mpi_cmp (sign_ctx->p, sign_ctx->q) > 0)
   {
@@ -712,7 +713,7 @@ Return: NULL for success, or an error string */
 const uschar *
 exim_dkim_signing_init(const uschar * privkey_pem, es_ctx * sign_ctx)
 {
-BIO * bp = BIO_new_mem_buf(privkey_pem, -1);
+BIO * bp = BIO_new_mem_buf((void *)privkey_pem, -1);
 
 if (!(sign_ctx->key = PEM_read_bio_PrivateKey(bp, NULL, NULL, NULL)))
   return string_sprintf("privkey PEM-block import: %s",
@@ -755,7 +756,7 @@ switch (hash)
 if (  (ctx = EVP_MD_CTX_new())
    && EVP_DigestSignInit(ctx, NULL, md, NULL, sign_ctx->key) > 0
    && EVP_DigestSign(ctx, NULL, &siglen, NULL, 0) > 0
-   && (sig->data = store_get(siglen))
+   && (sig->data = store_get(siglen, FALSE))
 
    /* Obtain the signature (slen could change here!) */
    && EVP_DigestSign(ctx, sig->data, &siglen, data->data, data->len) > 0
@@ -771,7 +772,7 @@ if (  (ctx = EVP_MD_CTX_create())
    && EVP_DigestSignInit(ctx, NULL, md, NULL, sign_ctx->key) > 0
    && EVP_DigestSignUpdate(ctx, data->data, data->len) > 0
    && EVP_DigestSignFinal(ctx, NULL, &siglen) > 0
-   && (sig->data = store_get(siglen))
+   && (sig->data = store_get(siglen, FALSE))
  
    /* Obtain the signature (slen could change here!) */
    && EVP_DigestSignFinal(ctx, sig->data, &siglen) > 0
@@ -831,7 +832,6 @@ const uschar *
 exim_dkim_verify(ev_ctx * verify_ctx, hashmethod hash, blob * data, blob * sig)
 {
 const EVP_MD * md;
-const uschar * where;
 
 switch (hash)
   {
@@ -847,36 +847,39 @@ if (!md)
   {
   EVP_MD_CTX * ctx;
 
-  if (  (ctx = EVP_MD_CTX_new())
-     && EVP_DigestVerifyInit(ctx, NULL, md, NULL, verify_ctx->key) > 0
-     && EVP_DigestVerify(ctx, sig->data, sig->len, data->data, data->len) > 0
-     )
-    { EVP_MD_CTX_free(ctx); return NULL; }
-
-  if (ctx) EVP_MD_CTX_free(ctx);
+  if ((ctx = EVP_MD_CTX_new()))
+    {
+    if (  EVP_DigestVerifyInit(ctx, NULL, md, NULL, verify_ctx->key) > 0
+       && EVP_DigestVerify(ctx, sig->data, sig->len, data->data, data->len) > 0
+       )
+      { EVP_MD_CTX_free(ctx); return NULL; }
+    EVP_MD_CTX_free(ctx);
+    }
   }
 else
 #endif
   {
   EVP_PKEY_CTX * ctx;
 
-  if (  (where = US"EVP_PKEY_CTX_new",
-            (ctx = EVP_PKEY_CTX_new(verify_ctx->key, NULL)))
-     && (where = US"EVP_PKEY_verify_init",
-                   EVP_PKEY_verify_init(ctx) > 0)
-     && (where = US"EVP_PKEY_CTX_set_rsa_padding",
-                   EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) > 0)
-     && (where = US"EVP_PKEY_CTX_set_signature_md",
-                   EVP_PKEY_CTX_set_signature_md(ctx, md) > 0)
-     && (where = US"EVP_PKEY_verify",
-                   EVP_PKEY_verify(ctx, sig->data, sig->len,
-                                   data->data, data->len) == 1)
-     )
-    { EVP_PKEY_CTX_free(ctx); return NULL; }
-
-  if (ctx) EVP_PKEY_CTX_free(ctx);
+  if ((ctx = EVP_PKEY_CTX_new(verify_ctx->key, NULL)))
+    {
+    if (  EVP_PKEY_verify_init(ctx) > 0
+       && EVP_PKEY_CTX_set_rsa_padding(ctx, RSA_PKCS1_PADDING) > 0
+       && EVP_PKEY_CTX_set_signature_md(ctx, md) > 0
+       && EVP_PKEY_verify(ctx, sig->data, sig->len,
+                                     data->data, data->len) == 1
+       )
+      { EVP_PKEY_CTX_free(ctx); return NULL; }
+    EVP_PKEY_CTX_free(ctx);
+
+    DEBUG(D_tls)
+      if (Ustrcmp(ERR_reason_error_string(ERR_peek_error()), "wrong signature length") == 0)
+       debug_printf("sig len (from msg hdr): %d, expected (from dns pubkey) %d\n",
+        (int) sig->len, EVP_PKEY_size(verify_ctx->key));
+    }
   }
-return string_sprintf("%s: %s", where, ERR_error_string(ERR_get_error(), NULL));
+
+return US ERR_error_string(ERR_get_error(), NULL);
 }