claws-mail/src/rfc822.c
2001-04-19 12:21:46 +00:00

424 lines
9.5 KiB
C

/*
* rfc822.c -- code for slicing and dicing RFC822 mail headers
*
* Copyright 1997 by Eric S. Raymond
* For license terms, see the file COPYING in this directory.
*
* Modified by Hiroyuki Yamamoto <hiro-y@kcn.ne.jp>
*/
#include <stdio.h>
#include <ctype.h>
#include <string.h>
#include <stdlib.h>
#include <glib.h>
#include "rfc822.h"
/* output noise level */
#define O_SILENT 0 /* mute, max squelch, etc. */
#define O_NORMAL 1 /* user-friendly */
#define O_VERBOSE 2 /* chatty */
#define O_DEBUG 3 /* prolix */
#define O_MONITOR O_VERBOSE
static int outlevel = O_SILENT;
#define POPBUFSIZE 512 /* max length of response (RFC1939) */
#define HEADER_END(p) ((p)[0] == '\n' && ((p)[1] != ' ' && (p)[1] != '\t'))
#ifdef TESTMAIN
static int verbose;
char *program_name = "rfc822";
#endif /* TESTMAIN */
char *reply_hack(buf, host)
/* hack message headers so replies will work properly */
char *buf; /* header to be hacked */
const char *host; /* server hostname */
{
char *from, *cp, last_nws = '\0', *parens_from = NULL;
int parendepth, state, has_bare_name_part, has_host_part;
#ifndef TESTMAIN
int addresscount = 1;
#endif /* TESTMAIN */
if (strncasecmp("From: ", buf, 6)
&& strncasecmp("To: ", buf, 4)
&& strncasecmp("Reply-To: ", buf, 10)
&& strncasecmp("Return-Path: ", buf, 13)
&& strncasecmp("Cc: ", buf, 4)
&& strncasecmp("Bcc: ", buf, 5)
&& strncasecmp("Resent-From: ", buf, 13)
&& strncasecmp("Resent-To: ", buf, 11)
&& strncasecmp("Resent-Cc: ", buf, 11)
&& strncasecmp("Resent-Bcc: ", buf, 12)
&& strncasecmp("Apparently-From:", buf, 16)
&& strncasecmp("Apparently-To:", buf, 14)
&& strncasecmp("Sender:", buf, 7)
&& strncasecmp("Resent-Sender:", buf, 14)
) {
return(buf);
}
#ifndef TESTMAIN
if (outlevel >= O_DEBUG)
fprintf(stdout, "About to rewrite %s", buf);
/* make room to hack the address; buf must be malloced */
for (cp = buf; *cp; cp++)
if (*cp == ',' || isspace(*cp))
addresscount++;
buf = (char *)g_realloc(buf, strlen(buf) + addresscount * strlen(host) + 1);
#endif /* TESTMAIN */
/*
* This is going to foo up on some ill-formed addresses.
* Note that we don't rewrite the fake address <> in order to
* avoid screwing up bounce suppression with a null Return-Path.
*/
parendepth = state = 0;
has_host_part = has_bare_name_part = FALSE;
for (from = buf; *from; from++)
{
#ifdef TESTMAIN
if (verbose)
{
printf("state %d: %s", state, buf);
printf("%*s^\n", from - buf + 10, " ");
}
#endif /* TESTMAIN */
if (state != 2) {
if (*from == '(')
++parendepth;
else if (*from == ')')
--parendepth;
}
if (!parendepth && !has_host_part)
switch (state)
{
case 0: /* before header colon */
if (*from == ':')
state = 1;
break;
case 1: /* we've seen the colon, we're looking for addresses */
if (!isspace(*from))
last_nws = *from;
if (*from == '<')
state = 3;
else if (*from == '@')
has_host_part = TRUE;
else if (*from == '"')
state = 2;
/*
* Not expanding on last non-WS == ';' deals with groupnames,
* an obscure misfeature described in sections
* 6.1, 6.2.6, and A.1.5 of the RFC822 standard.
*/
else if ((*from == ',' || HEADER_END(from))
&& has_bare_name_part
&& !has_host_part
&& last_nws != ';')
{
int hostlen;
char *p;
p = from;
if (parens_from)
from = parens_from;
while (isspace(*from) || (*from == ','))
--from;
from++;
hostlen = strlen(host);
for (cp = from + strlen(from); cp >= from; --cp)
cp[hostlen+1] = *cp;
*from++ = '@';
memcpy(from, host, hostlen);
from = p + hostlen + 1;
has_host_part = TRUE;
}
else if (from[1] == '('
&& has_bare_name_part
&& !has_host_part
&& last_nws != ';' && last_nws != ')')
{
parens_from = from;
}
else if (!isspace(*from))
has_bare_name_part = TRUE;
break;
case 2: /* we're in a string */
if (*from == '"')
state = 1;
break;
case 3: /* we're in a <>-enclosed address */
if (*from == '@')
has_host_part = TRUE;
else if (*from == '>' && from[-1] != '<')
{
state = 1;
if (!has_host_part)
{
int hostlen;
hostlen = strlen(host);
for (cp = from + strlen(from); cp >= from; --cp)
cp[hostlen+1] = *cp;
*from++ = '@';
memcpy(from, host, hostlen);
from += hostlen;
has_host_part = TRUE;
}
}
break;
}
/*
* If we passed a comma, reset everything.
*/
if (from[-1] == ',' && !parendepth) {
has_host_part = has_bare_name_part = FALSE;
parens_from = NULL;
}
}
#ifndef TESTMAIN
if (outlevel >= O_DEBUG)
fprintf(stdout, "Rewritten version is %s\n", buf);
#endif /* TESTMAIN */
return(buf);
}
char *nxtaddr(hdr)
/* parse addresses in succession out of a specified RFC822 header */
const char *hdr; /* header to be parsed, NUL to continue previous hdr */
{
static char *tp, address[POPBUFSIZE+1];
static const char *hp;
static int state, oldstate;
#ifdef TESTMAIN
static const char *orighdr;
#endif /* TESTMAIN */
int parendepth = 0;
#define START_HDR 0 /* before header colon */
#define SKIP_JUNK 1 /* skip whitespace, \n, and junk */
#define BARE_ADDRESS 2 /* collecting address without delimiters */
#define INSIDE_DQUOTE 3 /* inside double quotes */
#define INSIDE_PARENS 4 /* inside parentheses */
#define INSIDE_BRACKETS 5 /* inside bracketed address */
#define ENDIT_ALL 6 /* after last address */
if (hdr)
{
hp = hdr;
state = START_HDR;
#ifdef TESTMAIN
orighdr = hdr;
#endif /* TESTMAIN */
tp = address;
}
for (; *hp; hp++)
{
#ifdef TESTMAIN
if (verbose)
{
printf("state %d: %s", state, orighdr);
printf("%*s^\n", hp - orighdr + 10, " ");
}
#endif /* TESTMAIN */
if (state == ENDIT_ALL) /* after last address */
return(NULL);
else if (HEADER_END(hp))
{
state = ENDIT_ALL;
if (tp > address)
{
while (isspace(*--tp))
continue;
*++tp = '\0';
}
return(tp > address ? (tp = address) : (char *)NULL);
}
else if (*hp == '\\') /* handle RFC822 escaping */
{
if (state != INSIDE_PARENS)
{
*tp++ = *hp++; /* take the escape */
*tp++ = *hp; /* take following char */
}
}
else switch (state)
{
case START_HDR: /* before header colon */
if (*hp == ':')
state = SKIP_JUNK;
break;
case SKIP_JUNK: /* looking for address start */
if (*hp == '"') /* quoted string */
{
oldstate = SKIP_JUNK;
state = INSIDE_DQUOTE;
*tp++ = *hp;
}
else if (*hp == '(') /* address comment -- ignore */
{
parendepth = 1;
oldstate = SKIP_JUNK;
state = INSIDE_PARENS;
}
else if (*hp == '<') /* begin <address> */
{
state = INSIDE_BRACKETS;
tp = address;
}
else if (*hp != ',' && !isspace(*hp))
{
--hp;
state = BARE_ADDRESS;
}
break;
case BARE_ADDRESS: /* collecting address without delimiters */
if (*hp == ',') /* end of address */
{
if (tp > address)
{
*tp++ = '\0';
state = SKIP_JUNK;
return(tp = address);
}
}
else if (*hp == '(') /* beginning of comment */
{
parendepth = 1;
oldstate = BARE_ADDRESS;
state = INSIDE_PARENS;
}
else if (*hp == '<') /* beginning of real address */
{
state = INSIDE_BRACKETS;
tp = address;
}
else if (!isspace(*hp)) /* just take it, ignoring whitespace */
*tp++ = *hp;
break;
case INSIDE_DQUOTE: /* we're in a quoted string, copy verbatim */
if (*hp != '"')
*tp++ = *hp;
else
{
*tp++ = *hp;
state = oldstate;
}
break;
case INSIDE_PARENS: /* we're in a parenthesized comment, ignore */
if (*hp == '(')
++parendepth;
else if (*hp == ')')
--parendepth;
if (parendepth == 0)
state = oldstate;
break;
case INSIDE_BRACKETS: /* possible <>-enclosed address */
if (*hp == '>') /* end of address */
{
*tp++ = '\0';
state = SKIP_JUNK;
++hp;
return(tp = address);
}
else if (*hp == '<') /* nested <> */
tp = address;
else if (*hp == '"') /* quoted address */
{
*tp++ = *hp;
oldstate = INSIDE_BRACKETS;
state = INSIDE_DQUOTE;
}
else /* just copy address */
*tp++ = *hp;
break;
}
}
return(NULL);
}
#ifdef TESTMAIN
static void parsebuf(char *longbuf, int reply)
{
char *cp;
if (reply)
{
reply_hack(longbuf, "HOSTNAME.NET");
printf("Rewritten buffer: %s", longbuf);
}
else
if ((cp = nxtaddr(longbuf)) != (char *)NULL)
do {
printf("\t-> \"%s\"\n", cp);
} while
((cp = nxtaddr((char *)NULL)) != (char *)NULL);
}
main(int argc, char *argv[])
{
char buf[MSGBUFSIZE], longbuf[BUFSIZ];
int ch, reply;
verbose = reply = FALSE;
while ((ch = getopt(argc, argv, "rv")) != EOF)
switch(ch)
{
case 'r':
reply = TRUE;
break;
case 'v':
verbose = TRUE;
break;
}
while (fgets(buf, sizeof(buf)-1, stdin))
{
if (buf[0] == ' ' || buf[0] == '\t')
strcat(longbuf, buf);
else if (!strncasecmp("From: ", buf, 6)
|| !strncasecmp("To: ", buf, 4)
|| !strncasecmp("Reply-", buf, 6)
|| !strncasecmp("Cc: ", buf, 4)
|| !strncasecmp("Bcc: ", buf, 5))
strcpy(longbuf, buf);
else if (longbuf[0])
{
if (verbose)
fputs(longbuf, stdout);
parsebuf(longbuf, reply);
longbuf[0] = '\0';
}
}
if (longbuf[0])
{
if (verbose)
fputs(longbuf, stdout);
parsebuf(longbuf, reply);
}
}
#endif /* TESTMAIN */
/* rfc822.c end */