Commit bda33169 authored by Shane Kerr's avatar Shane Kerr

Handle IPv6 parsing better. Adds generic whitespace handling to

parser.
See RT ticket #16862 for more.
parent 9b21e73e
......@@ -54,6 +54,8 @@ suggested fixes to <dhcp-users@isc.org>.
Changes since 4.0.0a1
- Fix for parsing error on some IPv6 addresses.
- Invalid CIDR representation for IPv6 subnets or ranges now checked
for when loading configuration.
......
......@@ -34,7 +34,7 @@
#ifndef lint
static char copyright[] =
"$Id: conflex.c,v 1.110 2007/06/08 14:58:20 dhankins Exp $ Copyright (c) 2004-2007 Internet Systems Consortium. All rights reserved.\n";
"$Id: conflex.c,v 1.111 2007/06/20 10:38:55 shane Exp $ Copyright (c) 2004-2007 Internet Systems Consortium. All rights reserved.\n";
#endif /* not lint */
#include "dhcpd.h"
......@@ -43,6 +43,7 @@ static char copyright[] =
static int get_char PROTO ((struct parse *));
static enum dhcp_token get_token PROTO ((struct parse *));
static void skip_to_eol PROTO ((struct parse *));
static enum dhcp_token read_whitespace(int c, struct parse *cfile);
static enum dhcp_token read_string PROTO ((struct parse *));
static enum dhcp_token read_number PROTO ((int, struct parse *));
static enum dhcp_token read_num_or_name PROTO ((int, struct parse *));
......@@ -58,25 +59,29 @@ isc_result_t new_parse (cfile, file, inbuf, buflen, name, eolp)
{
struct parse *tmp;
tmp = dmalloc (sizeof (struct parse), MDL);
if (!tmp)
tmp = dmalloc(sizeof(struct parse), MDL);
if (tmp == NULL) {
return ISC_R_NOMEMORY;
memset (tmp, 0, sizeof *tmp);
}
tmp->token = 0;
/*
* We don't need to initialize things to zero here, since
* dmalloc() returns memory that is set to zero.
*/
/* tmp->token = 0; */
/* tmp->warnings_occurred = 0; */
/* tmp->bufix = 0; */
/* tmp->saved_state = NULL; */
tmp->tlname = name;
tmp->lpos = tmp -> line = 1;
tmp->cur_line = tmp -> line1;
tmp->prev_line = tmp -> line2;
tmp->token_line = tmp -> cur_line;
tmp->cur_line [0] = tmp -> prev_line [0] = 0;
tmp->warnings_occurred = 0;
tmp->cur_line = tmp->line1;
tmp->prev_line = tmp->line2;
tmp->token_line = tmp->cur_line;
tmp->cur_line[0] = tmp->prev_line[0] = 0;
tmp->file = file;
tmp->eol_token = eolp;
tmp->bufix = 0;
if (inbuf) {
if (inbuf != NULL) {
tmp->inbuf = inbuf;
tmp->buflen = buflen;
tmp->bufsiz = 0;
......@@ -86,7 +91,7 @@ isc_result_t new_parse (cfile, file, inbuf, buflen, name, eolp)
if (fstat(file, &sb) < 0)
return ISC_R_IOERROR;
tmp->bufsiz = tmp->buflen = (size_t) sb.st_size;
tmp->bufsiz = tmp->buflen = (size_t)sb.st_size;
tmp->inbuf = mmap(NULL, tmp->bufsiz, PROT_READ, MAP_SHARED,
file, 0);
......@@ -107,12 +112,63 @@ isc_result_t end_parse (cfile)
munmap((*cfile)->inbuf, (*cfile)->bufsiz);
close((*cfile)->file);
}
if ((*cfile)->saved_state != NULL) {
dfree((*cfile)->saved_state, MDL);
}
dfree(*cfile, MDL);
*cfile = NULL;
return ISC_R_SUCCESS;
}
/*
* Save the current state of the parser.
*
* Only one state may be saved. Any previous saved state is
* lost.
*/
isc_result_t
save_parse_state(struct parse *cfile) {
/*
* Free any previous saved state.
*/
if (cfile->saved_state != NULL) {
dfree(cfile->saved_state, MDL);
}
/*
* Save our current state.
*/
cfile->saved_state = dmalloc(sizeof(struct parse), MDL);
if (cfile->saved_state == NULL) {
return ISC_R_NOMEMORY;
}
memcpy(cfile->saved_state, cfile, sizeof(*cfile));
return ISC_R_SUCCESS;
}
/*
* Return the parser to the previous saved state.
*
* You must call save_parse_state() before calling
* restore_parse_state(), but you can call restore_parse_state() any
* number of times after that.
*/
isc_result_t
restore_parse_state(struct parse *cfile) {
struct parse *saved_state;
if (cfile->saved_state == NULL) {
return ISC_R_NOTYET;
}
saved_state = cfile->saved_state;
memcpy(cfile, saved_state, sizeof(*cfile));
cfile->saved_state = saved_state;
return ISC_R_SUCCESS;
}
static int get_char (cfile)
struct parse *cfile;
{
......@@ -150,9 +206,29 @@ static int get_char (cfile)
return c;
}
static enum dhcp_token get_token (cfile)
struct parse *cfile;
{
/*
* GENERAL NOTE ABOUT TOKENS
*
* We normally only want non-whitespace tokens. There are some
* circumstances where we *do* want to see whitespace (for example
* when parsing IPv6 addresses).
*
* Generally we use the next_token() function to read tokens. This
* in turn calls get_token, which does *not* return tokens for
* whitespace. Rather, it skips these.
*
* When we need to see whitespace, we us next_raw_token(), which also
* returns the WHITESPACE token.
*
* The peek_token() and peek_raw_token() functions work as expected.
*
* Warning: if you invoke peek_token(), then if there is a whitespace
* token, it will be lost, and subsequent use of next_raw_token() or
* peek_raw_token() will NOT see it.
*/
static enum dhcp_token
get_raw_token(struct parse *cfile) {
int c;
enum dhcp_token ttok;
static char tb [2];
......@@ -164,20 +240,12 @@ static enum dhcp_token get_token (cfile)
u = cfile -> ugflag;
c = get_char (cfile);
#ifdef OLD_LEXER
if (c == '\n' && p == 1 && !u
&& cfile -> comment_index < sizeof cfile -> comments)
cfile -> comments [cfile -> comment_index++] = '\n';
#endif
if (!(c == '\n' && cfile -> eol_token)
&& isascii (c) && isspace (c))
continue;
if (!((c == '\n') && cfile->eol_token) &&
isascii(c) && isspace(c)) {
ttok = read_whitespace(c, cfile);
break;
}
if (c == '#') {
#ifdef OLD_LEXER
if (cfile -> comment_index < sizeof cfile -> comments)
cfile -> comments [cfile -> comment_index++] = '#';
#endif
skip_to_eol (cfile);
continue;
}
......@@ -215,11 +283,17 @@ static enum dhcp_token get_token (cfile)
return ttok;
}
enum dhcp_token next_token (rval, rlen, cfile)
const char **rval;
unsigned *rlen;
struct parse *cfile;
{
/*
* The get_next_token() function consumes the next token and
* returns it to the caller.
*
* Since the code is almost the same for "normal" and "raw"
* input, we pass a flag to alter the way it works.
*/
static enum dhcp_token
get_next_token(const char **rval, unsigned *rlen,
struct parse *cfile, isc_boolean_t raw) {
int rv;
if (cfile -> token) {
......@@ -230,9 +304,17 @@ enum dhcp_token next_token (rval, rlen, cfile)
rv = cfile -> token;
cfile -> token = 0;
} else {
rv = get_token (cfile);
rv = get_raw_token(cfile);
cfile -> token_line = cfile -> cur_line;
}
if (!raw) {
while (rv == WHITESPACE) {
rv = get_raw_token(cfile);
cfile->token_line = cfile->cur_line;
}
}
if (rval)
*rval = cfile -> tval;
if (rlen)
......@@ -243,17 +325,56 @@ enum dhcp_token next_token (rval, rlen, cfile)
return rv;
}
enum dhcp_token peek_token (rval, rlen, cfile)
const char **rval;
unsigned int *rlen;
struct parse *cfile;
{
/*
* Get the next token from cfile and return it.
*
* If rval is non-NULL, set the pointer it contains to
* the contents of the token.
*
* If rlen is non-NULL, set the integer it contains to
* the length of the token.
*/
enum dhcp_token
next_token(const char **rval, unsigned *rlen, struct parse *cfile) {
return get_next_token(rval, rlen, cfile, ISC_FALSE);
}
/*
* The same as the next_token() function above, but will return space
* as the WHITESPACE token.
*/
enum dhcp_token
next_raw_token(const char **rval, unsigned *rlen, struct parse *cfile) {
return get_next_token(rval, rlen, cfile, ISC_TRUE);
}
/*
* The do_peek_token() function checks the next token without
* consuming it, and returns it to the caller.
*
* Since the code is almost the same for "normal" and "raw"
* input, we pass a flag to alter the way it works. (See the
* warning in the GENERAL NOTES ABOUT TOKENS above though.)
*/
enum dhcp_token
do_peek_token(const char **rval, unsigned int *rlen,
struct parse *cfile, isc_boolean_t raw) {
int x;
if (!cfile -> token) {
if (!cfile->token || (!raw && (cfile->token == WHITESPACE))) {
cfile -> tlpos = cfile -> lexchar;
cfile -> tline = cfile -> lexline;
cfile -> token = get_token (cfile);
do {
cfile->token = get_raw_token(cfile);
} while (!raw && (cfile->token == WHITESPACE));
if (cfile -> lexline != cfile -> tline)
cfile -> token_line = cfile -> prev_line;
......@@ -275,6 +396,36 @@ enum dhcp_token peek_token (rval, rlen, cfile)
return cfile -> token;
}
/*
* Get the next token from cfile and return it, leaving it for a
* subsequent call to next_token().
*
* Note that it WILL consume whitespace tokens.
*
* If rval is non-NULL, set the pointer it contains to
* the contents of the token.
*
* If rlen is non-NULL, set the integer it contains to
* the length of the token.
*/
enum dhcp_token
peek_token(const char **rval, unsigned *rlen, struct parse *cfile) {
return do_peek_token(rval, rlen, cfile, ISC_FALSE);
}
/*
* The same as the peek_token() function above, but will return space
* as the WHITESPACE token.
*/
enum dhcp_token
peek_raw_token(const char **rval, unsigned *rlen, struct parse *cfile) {
return do_peek_token(rval, rlen, cfile, ISC_TRUE);
}
static void skip_to_eol (cfile)
struct parse *cfile;
{
......@@ -283,16 +434,42 @@ static void skip_to_eol (cfile)
c = get_char (cfile);
if (c == EOF)
return;
#ifdef OLD_LEXER
if (cfile -> comment_index < sizeof (cfile -> comments))
comments [cfile -> comment_index++] = c;
#endif
if (c == EOL) {
return;
}
} while (1);
}
static enum dhcp_token
read_whitespace(int c, struct parse *cfile) {
int ofs;
/*
* Read as much whitespace as we have available.
*/
ofs = 0;
do {
cfile->tokbuf[ofs++] = c;
c = get_char(cfile);
} while (!((c == '\n') && cfile->eol_token) &&
isascii(c) && isspace(c));
/*
* Put the last (non-whitespace) character back.
*/
if (c != EOF) {
cfile->bufix--;
}
/*
* Return our token.
*/
cfile->tokbuf[ofs] = '\0';
cfile->tlen = ofs;
cfile->tval = cfile->tokbuf;
return WHITESPACE;
}
static enum dhcp_token read_string (cfile)
struct parse *cfile;
{
......@@ -406,9 +583,6 @@ static enum dhcp_token read_number (c, cfile)
int c;
struct parse *cfile;
{
#ifdef OLD_LEXER
int seenx = 0;
#endif
int i = 0;
int token = NUMBER;
......@@ -416,7 +590,6 @@ static enum dhcp_token read_number (c, cfile)
for (; i < sizeof cfile -> tokbuf; i++) {
c = get_char (cfile);
#ifndef OLD_LEXER
/* Promote NUMBER -> NUMBER_OR_NAME -> NAME, never demote.
* Except in the case of '0x' syntax hex, which gets called
* a NAME at '0x', and returned to NUMBER_OR_NAME once it's
......@@ -459,17 +632,6 @@ static enum dhcp_token read_number (c, cfile)
default:
log_fatal("read_number():%s:%d: impossible case", MDL);
}
#else /* OLD_LEXER */
if (!seenx && (c == 'x')) {
seenx = 1;
} else if (!isascii (c) || !isxdigit (c)) {
if (c != EOF) {
cfile -> bufix--;
cfile -> ugflag = 1;
}
break;
}
#endif /* OLD_LEXER */
cfile -> tokbuf [i] = c;
}
......
......@@ -34,7 +34,7 @@
#ifndef lint
static char copyright[] =
"$Id: parse.c,v 1.127 2007/06/07 15:52:29 dhankins Exp $ Copyright (c) 2004-2007 Internet Systems Consortium. All rights reserved.\n";
"$Id: parse.c,v 1.128 2007/06/20 10:38:55 shane Exp $ Copyright (c) 2004-2007 Internet Systems Consortium. All rights reserved.\n";
#endif /* not lint */
#include "dhcpd.h"
......@@ -274,7 +274,6 @@ int parse_ip_addr_or_hostname (expr, cfile, uniform)
unsigned len = sizeof addr;
char *name;
struct expression *x = (struct expression *)0;
struct parse cfile0;
int ipaddr = 0;
token = peek_token (&val, (unsigned *)0, cfile);
......@@ -287,12 +286,12 @@ int parse_ip_addr_or_hostname (expr, cfile, uniform)
* context first, and restore it after we know what
* we're dealing with.
*/
memcpy(&cfile0, cfile, sizeof(struct parse));
save_parse_state(cfile);
(void) next_token(NULL, NULL, cfile);
if (next_token(NULL, NULL, cfile) == DOT &&
next_token(NULL, NULL, cfile) == NUMBER)
ipaddr = 1;
memcpy(cfile, &cfile0, sizeof(struct parse));
restore_parse_state(cfile);
if (ipaddr &&
parse_numeric_aggregate (cfile, addr, &len, DOT, 10, 8))
......@@ -379,16 +378,24 @@ parse_ip6_addr(struct parse *cfile, struct iaddr *addr) {
char v6[sizeof("ffff:ffff:ffff:ffff:ffff:ffff:255.255.255.255")];
int v6_len;
/*
* First token is non-raw. This way we eat any whitespace before
* our IPv6 address begins, like one would expect.
*/
token = peek_token(&val, NULL, cfile);
/*
* Gather symbols.
*/
v6_len = 0;
for (;;) {
token = peek_token(&val, NULL, cfile);
if ((((token == NAME) || (token == NUMBER_OR_NAME)) &&
is_hex_string(val)) ||
(token == NUMBER) ||
(token == DOT) ||
(token == COLON)) {
next_token(&val, NULL, cfile);
next_raw_token(&val, NULL, cfile);
val_len = strlen(val);
if ((v6_len + val_len) >= sizeof(v6)) {
parse_warn(cfile, "Invalid IPv6 address.");
......@@ -401,9 +408,13 @@ parse_ip6_addr(struct parse *cfile, struct iaddr *addr) {
} else {
break;
}
token = peek_raw_token(&val, NULL, cfile);
}
v6[v6_len] = '\0';
/*
* Use inet_pton() for actual work.
*/
if (inet_pton(AF_INET6, v6, addr->iabuf) <= 0) {
parse_warn(cfile, "Invalid IPv6 address.");
skip_to_semi(cfile);
......
......@@ -266,15 +266,13 @@ struct parse {
int tlen;
char tokbuf [1500];
#ifdef OLD_LEXER
char comments [4096];
int comment_index;
#endif
int warnings_occurred;
int file;
char *inbuf;
size_t bufix, buflen;
size_t bufsiz;
struct parse *saved_state;
};
/* Variable-length array of data. */
......@@ -1577,8 +1575,14 @@ isc_result_t dhcp_set_control_state (control_object_state_t oldstate,
isc_result_t new_parse PROTO ((struct parse **, int,
char *, unsigned, const char *, int));
isc_result_t end_parse PROTO ((struct parse **));
isc_result_t save_parse_state(struct parse *cfile);
isc_result_t restore_parse_state(struct parse *cfile);
enum dhcp_token next_token PROTO ((const char **, unsigned *, struct parse *));
enum dhcp_token peek_token PROTO ((const char **, unsigned *, struct parse *));
enum dhcp_token next_raw_token(const char **rval, unsigned *rlen,
struct parse *cfile);
enum dhcp_token peek_raw_token(const char **rval, unsigned *rlen,
struct parse *cfile);
/* confpars.c */
void parse_trace_setup (void);
......
......@@ -342,7 +342,8 @@ enum dhcp_token {
LLT = 645,
EN = 646,
LL = 647,
RANGE6 = 648
RANGE6 = 648,
WHITESPACE = 649
};
#define is_identifier(x) ((x) >= FIRST_TOKEN && \
......
Markdown is supported
0% or .
You are about to add 0 people to the discussion. Proceed with caution.
Finish editing this message first!
Please register or to comment