[gmime] Report violations of RFC 5322 address specifications (#55)

[Rico Tzschichholz <ricotz src gnome org>]

commit d7d6254cceb87169616d96ceacd502f9505bbfda
Author: albrechtd <albrecht dress arcor de>
Date:   Mon Jan 28 21:50:43 2019 +0100

    Report violations of RFC 5322 address specifications (#55)
    
    Use the GMimeParserWarning facility to report a warning if
    (1) parsing an address failed with any error or
    (2) multiple adresses in a mailbox-list are not separated properly.

 examples/msgcheck.c          |  2 ++
 gmime/gmime-parser-options.h |  4 +++-
 gmime/internet-address.c     | 11 +++++++++++
 3 files changed, 16 insertions(+), 1 deletion(-)
---
diff --git a/examples/msgcheck.c b/examples/msgcheck.c
index 88addefc..2f78a616 100644
--- a/examples/msgcheck.c
+++ b/examples/msgcheck.c
@@ -52,6 +52,8 @@ errcode2str(GMimeParserWarning errcode)
                return "truncated message";
        case GMIME_WARN_MALFORMED_MESSAGE:
                return "malformed message";
+       case GMIME_WARN_INVALID_ADDRESS_SPEC:
+               return "invalid address specification";
        case GMIME_CRIT_INVALID_HEADER_NAME:
                return "invalid header name, parser may skip the message or parts of it";
        case GMIME_CRIT_CONFLICTING_HEADER:
diff --git a/gmime/gmime-parser-options.h b/gmime/gmime-parser-options.h
index a8dedbee..2c17b798 100644
--- a/gmime/gmime-parser-options.h
+++ b/gmime/gmime-parser-options.h
@@ -52,6 +52,7 @@ typedef enum {
  * @GMIME_WARN_MALFORMED_MULTIPART: no items in a `multipart/...`
  * @GMIME_WARN_TRUNCATED_MESSAGE: the message is truncated
  * @GMIME_WARN_MALFORMED_MESSAGE: the message is malformed
+ * @GMIME_WARN_INVALID_ADDRESS_SPEC: invalid address specification
  * @GMIME_CRIT_INVALID_HEADER_NAME: invalid header name, the parser may skip the message or parts of it
  * @GMIME_CRIT_CONFLICTING_HEADER: conflicting header
  * @GMIME_CRIT_CONFLICTING_PARAMETER: conflicting header parameter
@@ -73,7 +74,8 @@ typedef enum {
        GMIME_CRIT_CONFLICTING_HEADER,
        GMIME_CRIT_CONFLICTING_PARAMETER,
        GMIME_CRIT_MULTIPART_WITHOUT_BOUNDARY,
-       GMIME_WARN_INVALID_PARAMETER
+       GMIME_WARN_INVALID_PARAMETER,
+       GMIME_WARN_INVALID_ADDRESS_SPEC
 } GMimeParserWarning;
 
 /**
diff --git a/gmime/internet-address.c b/gmime/internet-address.c
index d515088e..b899d471 100644
--- a/gmime/internet-address.c
+++ b/gmime/internet-address.c
@@ -2050,6 +2050,8 @@ address_parse (GMimeParserOptions *options, AddressParserFlags flags, const char
        }
        
  error:
+       if (g_mime_parser_options_get_warning_callback (options) != NULL)
+               _g_mime_parser_options_warn (options, offset, GMIME_WARN_INVALID_ADDRESS_SPEC, *in);
        *address = NULL;
        *in = inptr;
        
@@ -2059,6 +2061,7 @@ address_parse (GMimeParserOptions *options, AddressParserFlags flags, const char
 static gboolean
 address_list_parse (InternetAddressList *list, GMimeParserOptions *options, const char **in, gboolean 
is_group, gint64 offset)
 {
+       gboolean can_warn = g_mime_parser_options_get_warning_callback (options) != NULL;
        InternetAddress *address;
        const char *charset;
        const char *inptr;
@@ -2072,6 +2075,8 @@ address_list_parse (InternetAddressList *list, GMimeParserOptions *options, cons
                return FALSE;
        
        while (*inptr) {
+               gboolean separator_between_addrs = FALSE;
+
                if (is_group && *inptr ==  ';')
                        break;
                
@@ -2086,6 +2091,9 @@ address_list_parse (InternetAddressList *list, GMimeParserOptions *options, cons
                        
                        if (charset)
                                address->charset = g_strdup (charset);
+
+                       if (INTERNET_ADDRESS_IS_GROUP(address))
+                               separator_between_addrs = TRUE;
                }
                
                /* Note: we loop here in case there are any null addresses between commas */
@@ -2099,8 +2107,11 @@ address_list_parse (InternetAddressList *list, GMimeParserOptions *options, cons
                        if (*inptr != ',')
                                break;
                        
+                       separator_between_addrs = TRUE;
                        inptr++;
                } while (TRUE);
+               if (can_warn && !(separator_between_addrs || (*inptr == '\0') || (is_group && (*inptr == 
';'))))
+                       _g_mime_parser_options_warn (options, offset, GMIME_WARN_INVALID_ADDRESS_SPEC, *in);
        }
        
        *in = inptr;