[Fix] Select the correct signature when doing simple canon

Issue: #1841
Closes: #1841
MFH: rspamd-1.6

diff --git a/src/libserver/dkim.c b/src/libserver/dkim.c
index ecbddb89a380e95e48dcf2a14e53317c1c0ec1e4..29cb30fb9c2f24bdfad4c7813e43beeabbe8bb01 100644 (file)
--- a/src/libserver/dkim.c
+++ b/src/libserver/dkim.c
@@ -93,6 +93,7 @@ enum rspamd_dkim_key_type {
 
 struct rspamd_dkim_common_ctx {
        rspamd_mempool_t *pool;
+       guint64 sig_hash;
        gsize len;
        gint header_canon_type;
        gint body_canon_type;
@@ -746,6 +747,8 @@ rspamd_create_dkim_context (const gchar *sig,
        p = sig;
        c = sig;
        end = p + strlen (p);
+       ctx->common.sig_hash = rspamd_cryptobox_fast_hash (sig, end - sig,
+                       rspamd_hash_seed ());
 
        while (p <= end) {
                switch (state) {
@@ -2099,9 +2102,10 @@ rspamd_dkim_canonize_header (struct rspamd_dkim_common_ctx *ctx,
                                }
 
                                PTR_ARRAY_FOREACH (ar, i, rh) {
-                                       if (rspamd_substring_search (rh->raw_value,
-                                                       rh->raw_len, dkim_domain,
-                                                       strlen (dkim_domain)) != -1) {
+                                       guint64 th = rspamd_cryptobox_fast_hash (rh->decoded,
+                                                       strlen (rh->decoded), rspamd_hash_seed ());
+
+                                       if (th == ctx->sig_hash) {
                                                rspamd_dkim_signature_update (ctx, rh->raw_value,
                                                                rh->raw_len);
                                                break;