-/*
- * 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.
- */
+/*****************************************************************************
+
+NAME:
+ rfc822.c -- code for slicing and dicing RFC822 mail headers
+
+ENTRY POINTS:
+ nextaddr() -- parse the next address out of an RFC822 header
+ reply_hack() -- append hostname to local header addresses
+
+THEORY:
+ How to parse RFC822 headers in C. This is not a fully conformant
+implementation of RFC822 or RFC2822, but it has been in production use
+in a widely-deployed MTA (fetcmail) since 1996 without complaints.
+Really perverse combinations of quoting and commenting could break it.
+
+AUTHOR:
+ Eric S. Raymond <esr@thyrsus.com>, 1997. This source code example
+is part of fetchmail and the Unix Cookbook, and are released under the
+MIT license. Compile with -DMAIN to build the demonstrator.
+
+******************************************************************************/
+
+#include "config.h"
#include <stdio.h>
#include <ctype.h>
#include <string.h>
-#if defined(STDC_HEADERS)
+#include <strings.h>
#include <stdlib.h>
-#endif
-#include "config.h"
#include "fetchmail.h"
+#include "sdump.h"
+
+#ifndef MAIN
+#include "i18n.h"
+#else
+#include <unistd.h>
+static int verbose;
+const char *program_name = "rfc822";
+#endif /* MAIN */
+
+#ifndef TRUE
+#define TRUE 1
+#define FALSE 0
+#endif
#define HEADER_END(p) ((p)[0] == '\n' && ((p)[1] != ' ' && (p)[1] != '\t'))
-#ifdef TESTMAIN
-static int verbose;
-char *program_name = "rfc822";
-#endif /* TESTMAIN */
+#define BEFORE_EOL(s) (strcspn((s), "\r\n"))
-char *reply_hack(buf, host)
+char *reply_hack(
+ char *buf /* header to be hacked */,
+ const char *host /* server hostname */,
+ size_t *length)
/* 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
+#ifndef MAIN
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)
+#endif /* MAIN */
+
+ if (strncasecmp("From:", buf, 5)
+ && strncasecmp("To:", buf, 3)
+ && strncasecmp("Reply-To:", buf, 9)
+ && strncasecmp("Return-Path:", buf, 12)
+ && strncasecmp("Cc:", buf, 3)
+ && strncasecmp("Bcc:", buf, 4)
+ && strncasecmp("Resent-From:", buf, 12)
+ && strncasecmp("Resent-To:", buf, 10)
+ && strncasecmp("Resent-Cc:", buf, 10)
+ && strncasecmp("Resent-Bcc:", buf, 11)
&& strncasecmp("Apparently-From:", buf, 16)
&& strncasecmp("Apparently-To:", buf, 14)
&& strncasecmp("Sender:", buf, 7)
return(buf);
}
-#ifndef TESTMAIN
- if (outlevel >= O_DEBUG)
- error_build(0, 0, "About to rewrite %s", buf);
+#ifndef MAIN
+ if (outlevel >= O_DEBUG) {
+ report_build(stdout, GT_("About to rewrite %s...\n"), (cp = sdump(buf, BEFORE_EOL(buf))));
+ xfree(cp);
+ }
/* make room to hack the address; buf must be malloced */
for (cp = buf; *cp; cp++)
- if (*cp == ',' || isspace(*cp))
+ if (*cp == ',' || isspace((unsigned char)*cp))
addresscount++;
- buf = (char *)xrealloc(buf, strlen(buf) + addresscount * strlen(host) + 1);
-#endif /* TESTMAIN */
+ buf = (char *)xrealloc(buf, strlen(buf) + addresscount * (strlen(host) + 1) + 1);
+#endif /* MAIN */
/*
* This is going to foo up on some ill-formed addresses.
has_host_part = has_bare_name_part = FALSE;
for (from = buf; *from; from++)
{
-#ifdef TESTMAIN
+#ifdef MAIN
if (verbose)
{
printf("state %d: %s", state, buf);
- printf("%*s^\n", from - buf + 10, " ");
+ printf("%*s^\n", (int)(from - buf + 10), " ");
}
-#endif /* TESTMAIN */
+#endif /* MAIN */
if (state != 2)
+ {
if (*from == '(')
++parendepth;
else if (*from == ')')
--parendepth;
+ }
if (!parendepth && !has_host_part)
switch (state)
break;
case 1: /* we've seen the colon, we're looking for addresses */
- if (!isspace(*from))
+ if (!isspace((unsigned char)*from))
last_nws = *from;
if (*from == '<')
state = 3;
- else if (*from == '@')
+ else if (*from == '@' || *from == '!')
has_host_part = TRUE;
else if (*from == '"')
state = 2;
p = from;
if (parens_from)
from = parens_from;
- while (isspace(*from) || (*from == ','))
+ while (isspace((unsigned char)*from) || (*from == ','))
--from;
from++;
hostlen = strlen(host);
{
parens_from = from;
}
- else if (!isspace(*from))
+ else if (!isspace((unsigned char)*from))
has_bare_name_part = TRUE;
break;
case 2: /* we're in a string */
if (*from == '"')
- state = 1;
+ {
+ char *bp;
+ int bscount;
+
+ bscount = 0;
+ for (bp = from - 1; *bp == '\\'; bp--)
+ bscount++;
+ if (!(bscount % 2))
+ state = 1;
+ }
break;
case 3: /* we're in a <>-enclosed address */
- if (*from == '@')
+ if (*from == '@' || *from == '!')
has_host_part = TRUE;
- else if (*from == '>' && from[-1] != '<')
+ else if (*from == '>' && (from > buf && from[-1] != '<'))
{
state = 1;
if (!has_host_part)
/*
* If we passed a comma, reset everything.
*/
- if (from[-1] == ',' && !parendepth) {
+ if ((from > buf && from[-1] == ',') && !parendepth) {
has_host_part = has_bare_name_part = FALSE;
parens_from = NULL;
}
}
-#ifndef TESTMAIN
- if (outlevel >= O_DEBUG)
- error_complete(0, 0, "Rewritten version is %s", buf);
-#endif /* TESTMAIN */
+#ifndef MAIN
+ if (outlevel >= O_DEBUG) {
+ report_complete(stdout, GT_("...rewritten version is %s.\n"),
+ (cp = sdump(buf, BEFORE_EOL(buf))));
+ xfree(cp)
+ }
+
+#endif /* MAIN */
+ *length = strlen(buf);
return(buf);
}
-char *nxtaddr(hdr)
+char *nxtaddr(const char *hdr /* header to be parsed, NUL to continue previous 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 char address[BUFSIZ];
+ static size_t tp;
static const char *hp;
static int state, oldstate;
-#ifdef TESTMAIN
+#ifdef MAIN
static const char *orighdr;
-#endif /* TESTMAIN */
+#endif /* MAIN */
int parendepth = 0;
#define START_HDR 0 /* before header colon */
#define INSIDE_BRACKETS 5 /* inside bracketed address */
#define ENDIT_ALL 6 /* after last address */
+#define NEXTTP() ((tp < sizeof(address)-1) ? tp++ : tp)
+
if (hdr)
{
hp = hdr;
state = START_HDR;
-#ifdef TESTMAIN
+#ifdef MAIN
orighdr = hdr;
-#endif /* TESTMAIN */
- tp = address;
+#endif /* MAIN */
+ tp = 0;
}
+ if (!hp) return NULL;
+
for (; *hp; hp++)
{
-#ifdef TESTMAIN
+#ifdef MAIN
if (verbose)
{
printf("state %d: %s", state, orighdr);
- printf("%*s^\n", hp - orighdr + 10, " ");
+ printf("%*s^\n", (int)(hp - orighdr + 10), " ");
}
-#endif /* TESTMAIN */
+#endif /* MAIN */
if (state == ENDIT_ALL) /* after last address */
return(NULL);
else if (HEADER_END(hp))
{
state = ENDIT_ALL;
- if (tp > address)
+ if (tp)
{
- while (isspace(*--tp))
- continue;
- *++tp = '\0';
+ while (tp > 0 && isspace((unsigned char)address[tp - 1]))
+ tp--;
+ address[tp] = '\0';
+ tp = 0;
+ return (address);
}
- return(tp > address ? (tp = address) : (char *)NULL);
+ return(NULL);
}
else if (*hp == '\\') /* handle RFC822 escaping */
{
if (state != INSIDE_PARENS)
{
- *tp++ = *hp++; /* take the escape */
- *tp++ = *hp; /* take following char */
+ address[NEXTTP()] = *hp++; /* take the escape */
+ address[NEXTTP()] = *hp; /* take following unsigned char */
}
}
else switch (state)
{
oldstate = SKIP_JUNK;
state = INSIDE_DQUOTE;
- *tp++ = *hp;
+ address[NEXTTP()] = *hp;
}
else if (*hp == '(') /* address comment -- ignore */
{
else if (*hp == '<') /* begin <address> */
{
state = INSIDE_BRACKETS;
- tp = address;
+ tp = 0;
}
- else if (*hp != ',' && !isspace(*hp))
+ else if (*hp != ',' && !isspace((unsigned char)*hp))
{
--hp;
state = BARE_ADDRESS;
case BARE_ADDRESS: /* collecting address without delimiters */
if (*hp == ',') /* end of address */
{
- if (tp > address)
+ if (tp)
{
- *tp++ = '\0';
+ address[NEXTTP()] = '\0';
state = SKIP_JUNK;
- return(tp = address);
+ tp = 0;
+ return(address);
}
}
else if (*hp == '(') /* beginning of comment */
else if (*hp == '<') /* beginning of real address */
{
state = INSIDE_BRACKETS;
- tp = address;
+ tp = 0;
}
- else if (!isspace(*hp)) /* just take it, ignoring whitespace */
- *tp++ = *hp;
+ else if (*hp == '"') /* quoted word, copy verbatim */
+ {
+ oldstate = state;
+ state = INSIDE_DQUOTE;
+ address[NEXTTP()] = *hp;
+ }
+ else if (!isspace((unsigned char)*hp)) /* just take it, ignoring whitespace */
+ address[NEXTTP()] = *hp;
break;
case INSIDE_DQUOTE: /* we're in a quoted string, copy verbatim */
- if (*hp != '"')
- *tp++ = *hp;
- else
- {
- *tp++ = *hp;
+ address[NEXTTP()] = *hp;
+ if (*hp == '"')
state = oldstate;
- }
break;
case INSIDE_PARENS: /* we're in a parenthesized comment, ignore */
case INSIDE_BRACKETS: /* possible <>-enclosed address */
if (*hp == '>') /* end of address */
{
- *tp++ = '\0';
+ address[NEXTTP()] = '\0';
state = SKIP_JUNK;
++hp;
- return(tp = address);
+ tp = 0;
+ return(address);
}
else if (*hp == '<') /* nested <> */
- tp = address;
+ tp = 0;
else if (*hp == '"') /* quoted address */
{
- *tp++ = *hp;
+ address[NEXTTP()] = *hp;
oldstate = INSIDE_BRACKETS;
state = INSIDE_DQUOTE;
}
else /* just copy address */
- *tp++ = *hp;
+ address[NEXTTP()] = *hp;
break;
}
}
return(NULL);
}
-#ifdef TESTMAIN
+#ifdef MAIN
static void parsebuf(char *longbuf, int reply)
{
char *cp;
+ size_t dummy;
if (reply)
{
- reply_hack(longbuf, "HOSTNAME.NET");
- printf("Rewritten buffer: %s", longbuf);
+ reply_hack(longbuf, "HOSTNAME.NET", &dummy);
+ printf("Rewritten buffer: %s", (char *)longbuf);
}
else
if ((cp = nxtaddr(longbuf)) != (char *)NULL)
do {
- printf("\t-> \"%s\"\n", cp);
+ printf("\t-> \"%s\"\n", (char *)cp);
} while
((cp = nxtaddr((char *)NULL)) != (char *)NULL);
}
-main(int argc, char *argv[])
+int main(int argc, char *argv[])
{
- char buf[MSGBUFSIZE], longbuf[BUFSIZ];
+ char buf[BUFSIZ], longbuf[BUFSIZ];
int ch, reply;
verbose = reply = FALSE;
break;
}
+ longbuf[0] = '\0';
+
while (fgets(buf, sizeof(buf)-1, stdin))
{
if (buf[0] == ' ' || buf[0] == '\t')
- strcat(longbuf, buf);
+ strlcat(longbuf, buf, sizeof(longbuf));
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);
+ strlcpy(longbuf, buf, sizeof(longbuf));
else if (longbuf[0])
{
if (verbose)
fputs(longbuf, stdout);
parsebuf(longbuf, reply);
}
+ exit(0);
}
-#endif /* TESTMAIN */
+#endif /* MAIN */
/* rfc822.c end */
projects / ~andy / fetchmail / blobdiff