istream-header-filter: Fixed header name validation to use case-insensitive comparison.

diff --git a/src/lib-mail/istream-header-filter.c b/src/lib-mail/istream-header-filter.c
index 1f034c31a1b5c131d46dbec7d3148c3ad9f2fa90..8146f18e601fdee7a0d6d1211f033d416dca5537 100644 (file)
--- a/src/lib-mail/istream-header-filter.c
+++ b/src/lib-mail/istream-header-filter.c
@@ -512,7 +512,8 @@ i_stream_create_header_filter(struct istream *input,
        mstream->headers = headers_count == 0 ? NULL :
                p_new(mstream->pool, const char *, headers_count);
        for (i = j = 0; i < headers_count; i++)  {
-               ret = j == 0 ? -1 : strcmp(mstream->headers[j-1], headers[i]);
+               ret = j == 0 ? -1 :
+                       strcasecmp(mstream->headers[j-1], headers[i]);
                if (ret == 0) {
                        /* drop duplicate */
                        continue;