Aren
/
NetBSD
1
0
Fork 0
Code Issues Pull Requests Packages Projects Releases Wiki Activity
NetBSD/gnu/dist/postfix/global/tok822_parse.c

573 lines
16 KiB
C
Raw Blame History

/*++
/* NAME
/* tok822_parse 3
/* SUMMARY
/* RFC 822 address parser
/* SYNOPSIS
/* #include <tok822.h>
/*
/* TOK822 *tok822_scan(str, tailp)
/* const char *str;
/* TOK822 **tailp;
/*
/* TOK822 *tok822_parse(str)
/* const char *str;
/*
/* TOK822 *tok822_scan_addr(str)
/* const char *str;
/*
/* VSTRING *tok822_externalize(buffer, tree, flags)
/* VSTRING *buffer;
/* TOK822 *tree;
/* int flags;
/*
/* VSTRING *tok822_internalize(buffer, tree, flags)
/* VSTRING *buffer;
/* TOK822 *tree;
/* int flags;
/* DESCRIPTION
/* This module converts address lists between string form and parse
/* tree formats. The string form can appear in two different ways:
/* external (or quoted) form, as used in message headers, and internal
/* (unquoted) form, as used internally by the mail software.
/* Although RFC 822 expects 7-bit data, these routines pay no
/* special attention to 8-bit characters.
/*
/* tok822_scan() converts the external-form string in \fIstr\fR
/* to a linear token list. The \fItailp\fR argument is a null pointer
/* or receives the pointer value of the last result list element.
/*
/* tok822_parse() converts the external-form address list in
/* \fIstr\fR to the corresponding token tree. The parser is permissive
/* and will not throw away information that it does not understand.
/* The parser adds missing commas between addresses.
/*
/* tok822_scan_addr() converts the external-form string in
/* \fIstr\fR to an address token tree. This is just string to
/* token list conversion; no parsing is done. This routine is
/* suitable for data should contain just one address and no
/* other information.
/*
/* tok822_externalize() converts a token list to external form.
/* Where appropriate, characters and strings are quoted and white
/* space is inserted. The \fIflags\fR argument is the binary OR of
/* zero or more of the following:
/* .IP TOK822_STR_WIPE
/* Initially, truncate the result to zero length.
/* .IP TOK822_STR_TERM
/* Append a null terminator to the result when done.
/* .IP TOK822_STR_LINE
/* Append a line break after each comma token, instead of appending
/* whitespace. It is up to the caller to concatenate short lines to
/* produce longer ones.
/* .PP
/* The macro TOK_822_NONE expresses that none of the above features
/* should be activated.
/*
/* The macro TOK822_STR_DEFL combines the TOK822_STR_WIPE and
/* TOK822_STR_TERM flags. This is useful for most token to string
/* conversions.
/*
/* The macro TOK822_STR_HEAD combines the TOK822_STR_TERM and
/* TOK822_STR_LINE flags. This is useful for the special case of
/* token to mail header conversion.
/*
/* tok822_internalize() converts a token list to string form,
/* without quoting. White space is inserted where appropriate.
/* The \fIflags\fR argument is as with tok822_externalize().
/* STANDARDS
/* .ad
/* .fi
/* RFC 822 (ARPA Internet Text Messages). In addition to this standard
/* this module implements additional operators such as % and !. These
/* are needed because the real world is not all RFC 822. Also, the ':'
/* operator is allowed to appear inside addresses, to accommodate DECnet.
/* In addition, 8-bit data is not given special treatment.
/* LICENSE
/* .ad
/* .fi
/* The Secure Mailer license must be distributed with this software.
/* AUTHOR(S)
/* Wietse Venema
/* IBM T.J. Watson Research
/* P.O. Box 704
/* Yorktown Heights, NY 10598, USA
/*--*/
/* System library. */
#include <sys_defs.h>
#include <ctype.h>
#include <string.h>
/* Utility library. */
#include <vstring.h>
#include <msg.h>
/* Global library. */
#include "tok822.h"
/*
* I suppose this is my favorite macro. Used heavily for tokenizing.
*/
#define COLLECT(t,s,c,cond) { \
while ((c = *(unsigned char *) s) != 0) { \
if (c == '\\') { \
if ((c = *(unsigned char *)++s) == 0) \
break; \
} else if (!(cond)) { \
break; \
} \
VSTRING_ADDCH(t->vstr, ISSPACE(c) ? ' ' : c); \
s++; \
} \
VSTRING_TERMINATE(t->vstr); \
}
#define COLLECT_SKIP_LAST(t,s,c,cond) { COLLECT(t,s,c,cond); if (*s) s++; }
/*
* Not quite as complex. The parser depends heavily on it.
*/
#define SKIP(tp, cond) { \
while (tp->type && (cond)) \
tp = tp->prev; \
}
#define MOVE_COMMENT_AND_CONTINUE(tp, right) { \
TOK822 *prev = tok822_unlink(tp); \
right = tok822_prepend(right, tp); \
tp = prev; \
continue; \
}
#define SKIP_MOVE_COMMENT(tp, cond, right) { \
while (tp->type && (cond)) { \
if (tp->type == TOK822_COMMENT) \
MOVE_COMMENT_AND_CONTINUE(tp, right); \
tp = tp->prev; \
} \
}
/*
* Single-character operators. We include the % and ! operators because not
* all the world is RFC822. XXX Make this operator list configurable when we
* have a real rewriting language.
*/
static char tok822_opchar[] = "|\"(),.:;<>@[]%!";
static void tok822_quote_atom(TOK822 *);
static const char *tok822_comment(TOK822 *, const char *);
static TOK822 *tok822_group(int, TOK822 *, TOK822 *, int);
static void tok822_copy_quoted(VSTRING *, char *, char *);
static int tok822_append_space(TOK822 *);
#define DO_WORD (1<<0) /* finding a word is ok here */
#define DO_GROUP (1<<1) /* doing an address group */
#define ADD_COMMA ',' /* resynchronize */
#define NO_MISSING_COMMA 0
/* tok822_internalize - token tree to string, internal form */
VSTRING *tok822_internalize(VSTRING *vp, TOK822 *tree, int flags)
{
TOK822 *tp;
if (flags & TOK822_STR_WIPE)
VSTRING_RESET(vp);
for (tp = tree; tp; tp = tp->next) {
switch (tp->type) {
case ',':
VSTRING_ADDCH(vp, tp->type);
if (flags & TOK822_STR_LINE) {
VSTRING_ADDCH(vp, '\n');
continue;
}
break;
case TOK822_ADDR:
tok822_internalize(vp, tp->head, TOK822_STR_NONE);
break;
case TOK822_ATOM:
case TOK822_COMMENT:
case TOK822_QSTRING:
vstring_strcat(vp, vstring_str(tp->vstr));
break;
case TOK822_DOMLIT:
VSTRING_ADDCH(vp, '[');
vstring_strcat(vp, vstring_str(tp->vstr));
VSTRING_ADDCH(vp, ']');
break;
case TOK822_STARTGRP:
VSTRING_ADDCH(vp, ':');
break;
default:
if (tp->type >= TOK822_MINTOK)
msg_panic("tok822_internalize: unknown operator %d", tp->type);
VSTRING_ADDCH(vp, tp->type);
}
if (tok822_append_space(tp))
VSTRING_ADDCH(vp, ' ');
}
if (flags & TOK822_STR_TERM)
VSTRING_TERMINATE(vp);
return (vp);
}
/* tok822_externalize - token tree to string, external form */
VSTRING *tok822_externalize(VSTRING *vp, TOK822 *tree, int flags)
{
TOK822 *tp;
if (flags & TOK822_STR_WIPE)
VSTRING_RESET(vp);
for (tp = tree; tp; tp = tp->next) {
switch (tp->type) {
case ',':
VSTRING_ADDCH(vp, tp->type);
if (flags & TOK822_STR_LINE) {
VSTRING_ADDCH(vp, '\n');
continue;
}
break;
case TOK822_ADDR:
tok822_externalize(vp, tp->head, TOK822_STR_NONE);
break;
case TOK822_ATOM:
vstring_strcat(vp, vstring_str(tp->vstr));
break;
case TOK822_COMMENT:
tok822_copy_quoted(vp, vstring_str(tp->vstr), "\\\r\n");
break;
case TOK822_QSTRING:
VSTRING_ADDCH(vp, '"');
tok822_copy_quoted(vp, vstring_str(tp->vstr), "\"\\\r\n");
VSTRING_ADDCH(vp, '"');
break;
case TOK822_DOMLIT:
VSTRING_ADDCH(vp, '[');
tok822_copy_quoted(vp, vstring_str(tp->vstr), "\"\\\r\n");
VSTRING_ADDCH(vp, ']');
break;
case TOK822_STARTGRP:
VSTRING_ADDCH(vp, ':');
break;
default:
if (tp->type >= TOK822_MINTOK)
msg_panic("tok822_externalize: unknown operator %d", tp->type);
VSTRING_ADDCH(vp, tp->type);
}
if (tok822_append_space(tp))
VSTRING_ADDCH(vp, ' ');
}
if (flags & TOK822_STR_TERM)
VSTRING_TERMINATE(vp);
return (vp);
}
/* tok822_copy_quoted - copy a string while quoting */
static void tok822_copy_quoted(VSTRING *vp, char *str, char *quote_set)
{
int ch;
while ((ch = *(unsigned char *) str++) != 0) {
if (strchr(quote_set, ch))
VSTRING_ADDCH(vp, '\\');
VSTRING_ADDCH(vp, ch);
}
}
/* tok822_append_space - see if space is needed after this token */
static int tok822_append_space(TOK822 *tp)
{
TOK822 *next;
if (tp == 0 || (next = tp->next) == 0 || tp->owner != 0)
return (0);
if (tp->type == ',' || tp->type == TOK822_STARTGRP || next->type == '<')
return (1);
#define NON_OPERATOR(x) \
(x->type == TOK822_ATOM || x->type == TOK822_QSTRING \
|| x->type == TOK822_COMMENT || x->type == TOK822_DOMLIT \
|| x->type == TOK822_ADDR)
return (NON_OPERATOR(tp) && NON_OPERATOR(next));
}
/* tok822_scan - tokenize string */
TOK822 *tok822_scan(const char *str, TOK822 **tailp)
{
TOK822 *head = 0;
TOK822 *tail = 0;
TOK822 *tp;
int ch;
while ((ch = *(unsigned char *) str++) != 0) {
if (ISSPACE(ch))
continue;
if (ch == '(') {
tp = tok822_alloc(TOK822_COMMENT, (char *) 0);
VSTRING_ADDCH(tp->vstr, ch);
str = tok822_comment(tp, str);
} else if (ch == '[') {
tp = tok822_alloc(TOK822_DOMLIT, (char *) 0);
COLLECT_SKIP_LAST(tp, str, ch, ch != ']');
} else if (ch == '"') {
tp = tok822_alloc(TOK822_QSTRING, (char *) 0);
COLLECT_SKIP_LAST(tp, str, ch, ch != '"');
} else if (ch != '\\' && strchr(tok822_opchar, ch)) {
tp = tok822_alloc(ch, (char *) 0);
} else {
tp = tok822_alloc(TOK822_ATOM, (char *) 0);
str -= 1; /* \ may be first */
COLLECT(tp, str, ch, !ISSPACE(ch) && !strchr(tok822_opchar, ch));
tok822_quote_atom(tp);
}
tail = (head == 0 ? head = tp : tok822_append(tail, tp));
}
if (tailp)
*tailp = tail;
return (head);
}
/* tok822_parse - translate external string to token tree */
TOK822 *tok822_parse(const char *str)
{
TOK822 *head;
TOK822 *tail;
TOK822 *right;
TOK822 *first_token;
TOK822 *last_token;
TOK822 *tp;
int state;
/*
* First, tokenize the string, from left to right. We are not allowed to
* throw away any information that we do not understand. With a flat
* token list that contains all tokens, we can always convert back to
* string form.
*/
if ((first_token = tok822_scan(str, &last_token)) == 0)
return (0);
/*
* For convenience, sandwich the token list between two sentinel tokens.
*/
#define GLUE(left,rite) { left->next = rite; rite->prev = left; }
head = tok822_alloc(0, (char *) 0);
GLUE(head, first_token);
tail = tok822_alloc(0, (char *) 0);
GLUE(last_token, tail);
/*
* Next step is to transform the token list into a parse tree. This is
* done most conveniently from right to left. If there is something that
* we do not understand, just leave it alone, don't throw it away. The
* address information that we're looking for sits in-between the current
* node (tp) and the one called right. Add missing commas on the fly.
*/
state = DO_WORD;
right = tail;
tp = tail->prev;
while (tp->type) {
if (tp->type == TOK822_COMMENT) { /* move comment to the side */
MOVE_COMMENT_AND_CONTINUE(tp, right);
} else if (tp->type == ';') { /* rh side of named group */
right = tok822_group(TOK822_ADDR, tp, right, ADD_COMMA);
state = DO_GROUP | DO_WORD;
} else if (tp->type == ':' && (state & DO_GROUP) != 0) {
tp->type = TOK822_STARTGRP;
(void) tok822_group(TOK822_ADDR, tp, right, NO_MISSING_COMMA);
SKIP(tp, tp->type != ',');
right = tp;
continue;
} else if (tp->type == '>') { /* rh side of <route> */
right = tok822_group(TOK822_ADDR, tp, right, ADD_COMMA);
SKIP_MOVE_COMMENT(tp, tp->type != '<', right);
(void) tok822_group(TOK822_ADDR, tp, right, NO_MISSING_COMMA);
SKIP(tp, tp->type > 0xff || strchr(">;,:", tp->type) == 0);
right = tp;
state |= DO_WORD;
continue;
} else if (tp->type == TOK822_ATOM || tp->type == TOK822_QSTRING
|| tp->type == TOK822_DOMLIT) {
if ((state & DO_WORD) == 0)
right = tok822_group(TOK822_ADDR, tp, right, ADD_COMMA)->next;
state &= ~DO_WORD;
} else if (tp->type == ',') {
right = tok822_group(TOK822_ADDR, tp, right, NO_MISSING_COMMA);
state |= DO_WORD;
} else {
state |= DO_WORD;
}
tp = tp->prev;
}
(void) tok822_group(TOK822_ADDR, tp, right, NO_MISSING_COMMA);
/*
* Discard the sentinel tokens on the left and right extremes. Properly
* terminate the resulting list.
*/
tp = (head->next != tail ? head->next : 0);
tok822_cut_before(head->next);
tok822_free(head);
tok822_cut_before(tail);
tok822_free(tail);
return (tp);
}
/* tok822_quote_atom - see if an atom needs quoting when externalized */
static void tok822_quote_atom(TOK822 *tp)
{
char *cp;
int ch;
/*
* RFC 822 expects 7-bit data. Rather than quoting every 8-bit character
* (and still passing it on as 8-bit data) we leave 8-bit data alone.
*/
for (cp = vstring_str(tp->vstr); (ch = *(unsigned char *) cp) != 0; cp++) {
if ( /* !ISASCII(ch) || */ ISSPACE(ch)
|| ISCNTRL(ch) || strchr(tok822_opchar, ch)) {
tp->type = TOK822_QSTRING;
break;
}
}
}
/* tok822_comment - tokenize comment */
const char *tok822_comment(TOK822 *tp, const char *str)
{
int ch;
while ((ch = *(unsigned char *) str) != 0) {
VSTRING_ADDCH(tp->vstr, ISSPACE(ch) ? ' ' : ch);
str++;
if (ch == '(') { /* comments can nest! */
str = tok822_comment(tp, str);
} else if (ch == ')') {
break;
} else if (ch == '\\') {
vstring_truncate(tp->vstr, VSTRING_LEN(tp->vstr) - 1);
if ((ch = *(unsigned char *) str) == 0)
break;
VSTRING_ADDCH(tp->vstr, ch);
str++;
}
}
VSTRING_TERMINATE(tp->vstr);
return (str);
}
/* tok822_group - cluster a group of tokens */
TOK822 *tok822_group(int group_type, TOK822 *left, TOK822 *right, int sync_type)
{
TOK822 *group;
TOK822 *sync;
TOK822 *first;
/*
* Cluster the tokens between left and right under their own parse tree
* node. Optionally insert a resync token.
*/
if (left != right && (first = left->next) != right) {
tok822_cut_before(right);
tok822_cut_before(first);
group = tok822_alloc(group_type, (char *) 0);
tok822_sub_append(group, first);
tok822_append(left, group);
tok822_append(group, right);
if (sync_type) {
sync = tok822_alloc(sync_type, (char *) 0);
tok822_append(left, sync);
}
}
return (left);
}
/* tok822_scan_addr - convert external address string to address token */
TOK822 *tok822_scan_addr(const char *addr)
{
TOK822 *tree = tok822_alloc(TOK822_ADDR, (char *) 0);
tree->head = tok822_scan(addr, &tree->tail);
return (tree);
}
#ifdef TEST
#include <vstream.h>
#include <vstring_vstream.h>
/* tok822_print - display token */
static void tok822_print(TOK822 *tp, int indent)
{
if (tp->type < TOK822_MINTOK) {
vstream_printf("%*s %s \"%c\"\n", indent, "", "OP", tp->type);
} else if (tp->type == TOK822_ADDR) {
vstream_printf("%*s %s\n", indent, "", "address");
} else {
vstream_printf("%*s %s \"%s\"\n", indent, "",
tp->type == TOK822_COMMENT ? "comment" :
tp->type == TOK822_ATOM ? "atom" :
tp->type == TOK822_QSTRING ? "quoted string" :
tp->type == TOK822_DOMLIT ? "domain literal" :
tp->type == TOK822_ADDR ? "address" :
"unknown\n", vstring_str(tp->vstr));
}
}
int main(int unused_argc, char **unused_argv)
{
VSTRING *vp = vstring_alloc(100);
TOK822 *list;
TOK822 *tp;
TOK822 *ap;
int indent = 0;
VSTRING *buf = vstring_alloc(100);
while (vstring_fgets(buf, VSTREAM_IN)) {
list = tok822_parse(vstring_str(buf));
for (tp = list; tp; tp = tp->next) {
tok822_print(tp, indent);
if (tp->type == TOK822_ADDR) {
indent += 2;
for (ap = tp->head; ap; ap = ap->next)
tok822_print(ap, indent);
indent -= 2;
}
}
vstream_printf("\n");
vstream_printf("Internalized:\n%s\n\n",
vstring_str(tok822_internalize(vp, list, TOK822_STR_DEFL)));
vstream_printf("Externalized, no newlines inserted:\n%s\n\n",
vstring_str(tok822_externalize(vp, list, TOK822_STR_DEFL)));
vstream_printf("Externalized, newlines inserted:\n%s\n\n",
vstring_str(tok822_externalize(vp, list,
TOK822_STR_DEFL | TOK822_STR_LINE)));
vstream_fflush(VSTREAM_OUT);
tok822_free_tree(list);
}
vstring_free(vp);
vstring_free(buf);
}
#endif
Reference in New Issue View Git Blame Copy Permalink