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/* -*- Mode: C; tab-width: 8; indent-tabs-mode: t; c-basic-offset: 8 -*- */
/*
* Copyright (C) 2002 Ximian, Inc.
*
* Authors: Jeffrey Stedfast <fejj@ximian.com>
* Michael Zucchi <notzed@ximian.com>
*
* This program is free software; you can redistribute it and/or
* modify it under the terms of version 2 of the GNU General Public
* License as published by the Free Software Foundation.
*
* This program is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* General Public License for more details.
*
* You should have received a copy of the GNU General Public
* License along with this program; if not, write to the
* Free Software Foundation, Inc., 59 Temple Place - Suite 330,
* Boston, MA 02111-1307, USA.
*/
/* canonicalisation filter, used for secure mime incoming and outgoing */
#ifdef HAVE_CONFIG_H
#include <config.h>
#endif
#include <string.h>
#include <ctype.h>
#include "camel-mime-filter-canon.h"
static void filter (CamelMimeFilter *f, char *in, size_t len, size_t prespace,
char **out, size_t *outlen, size_t *outprespace);
static void complete (CamelMimeFilter *f, char *in, size_t len,
size_t prespace, char **out, size_t *outlen,
size_t *outprespace);
static void reset (CamelMimeFilter *f);
static void
camel_mime_filter_canon_class_init (CamelMimeFilterCanonClass *klass)
{
CamelMimeFilterClass *mime_filter_class = (CamelMimeFilterClass *) klass;
mime_filter_class->filter = filter;
mime_filter_class->complete = complete;
mime_filter_class->reset = reset;
}
CamelType
camel_mime_filter_canon_get_type (void)
{
static CamelType type = CAMEL_INVALID_TYPE;
if (type == CAMEL_INVALID_TYPE) {
type = camel_type_register (camel_mime_filter_get_type(), "CamelMimeFilterCanon",
sizeof (CamelMimeFilterCanon),
sizeof (CamelMimeFilterCanonClass),
(CamelObjectClassInitFunc) camel_mime_filter_canon_class_init,
NULL,
NULL,
NULL);
}
return type;
}
static void
filter(CamelMimeFilter *f, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace)
{
register unsigned char *inptr, c;
const unsigned char *inend, *start;
char *starto;
register char *o;
int lf = 0;
guint32 flags;
flags = ((CamelMimeFilterCanon *)f)->flags;
/* first, work out how much space we need */
inptr = in;
inend = in+len;
while (inptr < inend)
if (*inptr++ == '\n')
lf++;
/* worst case, extra 3 chars per line
"From \n" -> "=46rom \r\n"
We add 1 extra incase we're called from complete, when we didn't end in \n */
camel_mime_filter_set_size(f, len+lf*3+4, FALSE);
o = f->outbuf;
inptr = in;
start = inptr;
starto = o;
while (inptr < inend) {
/* first, check start of line, we always start at the start of the line */
c = *inptr;
if (flags & CAMEL_MIME_FILTER_CANON_FROM && c == 'F') {
inptr++;
if (inptr < inend-4) {
if (strncmp(inptr, "rom ", 4) == 0) {
*o++ = '=';
*o++ = '4';
*o++ = '6';
} else
*o++ = 'F';
*o++ = *inptr++;
*o++ = *inptr++;
*o++ = *inptr++;
*o++ = *inptr++;
} else {
break;
}
}
/* now scan for end of line */
while (inptr < inend) {
c = *inptr++;
if (c == '\n') {
/* check to strip trailing space */
if (flags & CAMEL_MIME_FILTER_CANON_STRIP) {
while (o>starto && (o[-1] == ' ' || o[-1] == '\t' || o[-1]=='\r'))
o--;
}
/* check end of line canonicalisation */
if (o>starto) {
if (flags & CAMEL_MIME_FILTER_CANON_CRLF) {
if (o[-1] != '\r')
*o++ = '\r';
} else {
if (o[-1] == '\r')
o--;
}
} else if (flags & CAMEL_MIME_FILTER_CANON_CRLF) {
/* empty line */
*o++ = '\r';
}
*o++ = c;
start = inptr;
starto = o;
break;
} else
*o++ = c;
}
}
/* TODO: We should probably track if we end somewhere in the middle of a line,
otherwise we potentially backup a full line, which could be large */
/* we got to the end of the data without finding anything, backup to start and re-process next time around */
camel_mime_filter_backup(f, start, inend - start);
*out = f->outbuf;
*outlen = starto - f->outbuf;
*outprespace = f->outpre;
}
static void
complete(CamelMimeFilter *f, char *in, size_t len, size_t prespace, char **out, size_t *outlen, size_t *outprespace)
{
unsigned char *inptr, *inend;
char *o, *starto;
guint32 flags;
if (len)
filter(f, in, len, prespace, out, outlen, outprespace);
/* the data didn't contain an eol or was too short for "From ", we only need to check for "From" and add an eol */
if (f->backlen) {
inptr = (unsigned char *)f->backbuf;
inend = (unsigned char *)f->backbuf + f->backlen;
starto = o = *out + *outlen;
flags = ((CamelMimeFilterCanon *)f)->flags;
/* Check any embedded "From " */
if (f->backlen >= 5
&& (flags & CAMEL_MIME_FILTER_CANON_FROM)
&& strcmp(inptr, "From ") == 0) {
strcpy(o, "=46rom ");
o += 7;
inptr += 5;
}
/* copy the rest of it */
while (inptr < inend)
*o++ = *inptr++;
/* check to strip trailing space */
if (flags & CAMEL_MIME_FILTER_CANON_STRIP) {
while (o>starto && (o[-1] == ' ' || o[-1] == '\t' || o[-1]=='\r'))
o--;
}
#if 0
/* Note: #if 0'd out because we do not want to add a
* \r\n for PGP/MIME verification if it isn't there in
* the original content stream */
/* check end of line canonicalisation */
if (o>starto) {
if (flags & CAMEL_MIME_FILTER_CANON_CRLF) {
if (o[-1] != '\r')
*o++ = '\r';
} else {
if (o[-1] == '\r')
o--;
}
}
/* and always finish with an eol */
*o++ = '\n';
#endif
*outlen = o - *out;
f->backlen = 0;
}
}
static void
reset (CamelMimeFilter *f)
{
/* no-op */
}
CamelMimeFilter *
camel_mime_filter_canon_new(guint32 flags)
{
CamelMimeFilterCanon *chomp = CAMEL_MIME_FILTER_CANON (camel_object_new (CAMEL_MIME_FILTER_CANON_TYPE));
chomp->flags = flags;
return (CamelMimeFilter *) chomp;
}
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