File: [local] / src / usr.sbin / snmpd / parse.y (download)
Revision 1.14, Wed Feb 27 15:12:10 2008 UTC (16 years, 3 months ago) by mpf
Branch: MAIN
CVS Tags: OPENBSD_4_3_BASE, OPENBSD_4_3 Changes since 1.13: +2 -2 lines
Unbreak parser by initializing topfile correctly.
I got fooled by patch(1). Sorry.
Found by and OK thib@.
|
/* $OpenBSD: parse.y,v 1.14 2008/02/27 15:12:10 mpf Exp $ */
/*
* Copyright (c) 2007, 2008 Reyk Floeter <reyk@vantronix.net>
* Copyright (c) 2004, 2005 Esben Norby <norby@openbsd.org>
* Copyright (c) 2004 Ryan McBride <mcbride@openbsd.org>
* Copyright (c) 2002, 2003, 2004 Henning Brauer <henning@openbsd.org>
* Copyright (c) 2001 Markus Friedl. All rights reserved.
* Copyright (c) 2001 Daniel Hartmeier. All rights reserved.
* Copyright (c) 2001 Theo de Raadt. All rights reserved.
*
* Permission to use, copy, modify, and distribute this software for any
* purpose with or without fee is hereby granted, provided that the above
* copyright notice and this permission notice appear in all copies.
*
* THE SOFTWARE IS PROVIDED "AS IS" AND THE AUTHOR DISCLAIMS ALL WARRANTIES
* WITH REGARD TO THIS SOFTWARE INCLUDING ALL IMPLIED WARRANTIES OF
* MERCHANTABILITY AND FITNESS. IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR
* ANY SPECIAL, DIRECT, INDIRECT, OR CONSEQUENTIAL DAMAGES OR ANY DAMAGES
* WHATSOEVER RESULTING FROM LOSS OF USE, DATA OR PROFITS, WHETHER IN AN
* ACTION OF CONTRACT, NEGLIGENCE OR OTHER TORTIOUS ACTION, ARISING OUT OF
* OR IN CONNECTION WITH THE USE OR PERFORMANCE OF THIS SOFTWARE.
*/
%{
#include <sys/types.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <sys/queue.h>
#include <sys/tree.h>
#include <netinet/in.h>
#include <net/if.h>
#include <arpa/inet.h>
#include <arpa/nameser.h>
#include <ctype.h>
#include <unistd.h>
#include <err.h>
#include <errno.h>
#include <event.h>
#include <limits.h>
#include <stdint.h>
#include <stdarg.h>
#include <stdio.h>
#include <netdb.h>
#include <string.h>
#include "snmpd.h"
#include "mib.h"
TAILQ_HEAD(files, file) files = TAILQ_HEAD_INITIALIZER(files);
static struct file {
TAILQ_ENTRY(file) entry;
FILE *stream;
char *name;
int lineno;
int errors;
} *file, *topfile;
struct file *pushfile(const char *, int);
int popfile(void);
int check_file_secrecy(int, const char *);
int yyparse(void);
int yylex(void);
int yyerror(const char *, ...);
int kw_cmp(const void *, const void *);
int lookup(char *);
int lgetc(int);
int lungetc(int);
int findeol(void);
TAILQ_HEAD(symhead, sym) symhead = TAILQ_HEAD_INITIALIZER(symhead);
struct sym {
TAILQ_ENTRY(sym) entry;
int used;
int persist;
char *nam;
char *val;
};
int symset(const char *, const char *, int);
char *symget(const char *);
struct snmpd *conf = NULL;
static int errors = 0;
static struct addresslist *hlist;
struct address *host_v4(const char *);
struct address *host_v6(const char *);
int host_dns(const char *, struct addresslist *,
int, in_port_t, struct ber_oid *, char *);
int host(const char *, struct addresslist *,
int, in_port_t, struct ber_oid *, char *);
typedef struct {
union {
int64_t number;
char *string;
struct host *host;
struct timeval tv;
struct ber_oid *oid;
struct {
int type;
void *data;
long long value;
} data;
} v;
int lineno;
} YYSTYPE;
%}
%token INCLUDE
%token LISTEN ON
%token SYSTEM CONTACT DESCR LOCATION NAME OBJECTID SERVICES
%token READONLY READWRITE OCTETSTRING INTEGER COMMUNITY TRAP RECEIVER
%token ERROR
%token <v.string> STRING
%token <v.number> NUMBER
%type <v.string> hostcmn
%type <v.number> optwrite
%type <v.data> objtype
%type <v.oid> oid hostoid
%%
grammar : /* empty */
| grammar include '\n'
| grammar '\n'
| grammar varset '\n'
| grammar main '\n'
| grammar system '\n'
| grammar mib '\n'
| grammar error '\n' { file->errors++; }
;
include : INCLUDE STRING {
struct file *nfile;
if ((nfile = pushfile($2, 0)) == NULL) {
yyerror("failed to include file %s", $2);
free($2);
YYERROR;
}
free($2);
file = nfile;
lungetc('\n');
}
varset : STRING '=' STRING {
if (symset($1, $3, 0) == -1)
fatal("cannot store variable");
free($1);
free($3);
}
;
main : LISTEN ON STRING {
struct addresslist al;
struct address *h;
TAILQ_INIT(&al);
if (host($3, &al, 1, SNMPD_PORT, NULL, NULL) <= 0) {
yyerror("invalid ip address: %s", $3);
free($3);
YYERROR;
}
free($3);
h = TAILQ_FIRST(&al);
bcopy(&h->ss, &conf->sc_address.ss, sizeof(*h));
conf->sc_address.port = h->port;
while ((h = TAILQ_FIRST(&al)) != NULL) {
TAILQ_REMOVE(&al, h, entry);
free(h);
}
}
| READONLY COMMUNITY STRING {
if (strlcpy(conf->sc_rdcommunity, $3,
sizeof(conf->sc_rdcommunity)) >=
sizeof(conf->sc_rdcommunity)) {
yyerror("r/o community name too long");
free($3);
YYERROR;
}
free($3);
}
| READWRITE COMMUNITY STRING {
if (strlcpy(conf->sc_rwcommunity, $3,
sizeof(conf->sc_rwcommunity)) >=
sizeof(conf->sc_rwcommunity)) {
yyerror("r/w community name too long");
free($3);
YYERROR;
}
free($3);
}
| TRAP COMMUNITY STRING {
if (strlcpy(conf->sc_trcommunity, $3,
sizeof(conf->sc_trcommunity)) >=
sizeof(conf->sc_trcommunity)) {
yyerror("r/w community name too long");
free($3);
YYERROR;
}
free($3);
}
| TRAP RECEIVER {
hlist = &conf->sc_trapreceivers;
} host {
hlist = NULL;
}
;
system : SYSTEM sysmib
;
sysmib : CONTACT STRING {
struct ber_oid o = OID(MIB_sysContact);
mps_set(&o, $2, strlen($2));
}
| DESCR STRING {
struct ber_oid o = OID(MIB_sysDescr);
mps_set(&o, $2, strlen($2));
}
| LOCATION STRING {
struct ber_oid o = OID(MIB_sysLocation);
mps_set(&o, $2, strlen($2));
}
| NAME STRING {
struct ber_oid o = OID(MIB_sysName);
mps_set(&o, $2, strlen($2));
}
| OBJECTID oid {
struct ber_oid o = OID(MIB_sysOID);
mps_set(&o, $2, sizeof(struct ber_oid));
}
| SERVICES NUMBER {
struct ber_oid o = OID(MIB_sysServices);
mps_set(&o, NULL, $2);
}
;
mib : OBJECTID oid NAME STRING optwrite objtype {
struct oid *oid;
if ((oid = (struct oid *)
calloc(1, sizeof(*oid))) == NULL) {
yyerror("calloc");
free($2);
free($6.data);
YYERROR;
}
smi_oidlen($2);
bcopy($2, &oid->o_id, sizeof(struct ber_oid));
free($2);
oid->o_name = $4;
oid->o_data = $6.data;
oid->o_val = $6.value;
switch ($6.type) {
case 1:
oid->o_get = mps_getint;
oid->o_set = mps_setint;
break;
case 2:
oid->o_get = mps_getstr;
oid->o_set = mps_setstr;
break;
}
oid->o_flags = OID_RD|OID_DYNAMIC;
if ($5)
oid->o_flags |= OID_WR;
smi_insert(oid);
}
;
objtype : INTEGER NUMBER {
$$.type = 1;
$$.data = NULL;
$$.value = $2;
}
| OCTETSTRING STRING {
$$.type = 2;
$$.data = $2;
$$.value = strlen($2);
}
;
optwrite : READONLY { $$ = 0; }
| READWRITE { $$ = 1; }
;
oid : STRING {
struct ber_oid *sysoid;
if ((sysoid =
calloc(1, sizeof(*sysoid))) == NULL) {
yyerror("calloc");
free($1);
YYERROR;
}
if (ber_string2oid($1, sysoid) == -1) {
yyerror("invalid OID: %s", $1);
free(sysoid);
free($1);
YYERROR;
}
free($1);
$$ = sysoid;
}
;
hostoid : /* empty */ { $$ = NULL; }
| OBJECTID oid { $$ = $2; }
;
hostcmn : /* empty */ { $$ = NULL; }
| COMMUNITY STRING { $$ = $2; }
;
hostdef : STRING hostoid hostcmn {
if (host($1, hlist, 1,
SNMPD_TRAPPORT, $2, $3) <= 0) {
yyerror("invalid host: %s", $1);
free($1);
YYERROR;
}
free($1);
}
;
hostlist : /* empty */
| hostlist comma hostdef
;
host : hostdef
| '{' hostlist '}'
;
comma : /* empty */
| ','
;
%%
struct keywords {
const char *k_name;
int k_val;
};
int
yyerror(const char *fmt, ...)
{
va_list ap;
file->errors++;
va_start(ap, fmt);
fprintf(stderr, "%s:%d: ", file->name, yylval.lineno);
vfprintf(stderr, fmt, ap);
fprintf(stderr, "\n");
va_end(ap);
return (0);
}
int
kw_cmp(const void *k, const void *e)
{
return (strcmp(k, ((const struct keywords *)e)->k_name));
}
int
lookup(char *s)
{
/* this has to be sorted always */
static const struct keywords keywords[] = {
{ "community", COMMUNITY },
{ "contact", CONTACT },
{ "description", DESCR },
{ "include", INCLUDE },
{ "integer", INTEGER },
{ "listen", LISTEN },
{ "location", LOCATION },
{ "name", NAME },
{ "oid", OBJECTID },
{ "on", ON },
{ "read-only", READONLY },
{ "read-write", READWRITE },
{ "receiver", RECEIVER },
{ "services", SERVICES },
{ "string", OCTETSTRING },
{ "system", SYSTEM },
{ "trap", TRAP }
};
const struct keywords *p;
p = bsearch(s, keywords, sizeof(keywords)/sizeof(keywords[0]),
sizeof(keywords[0]), kw_cmp);
if (p)
return (p->k_val);
else
return (STRING);
}
#define MAXPUSHBACK 128
char *parsebuf;
int parseindex;
char pushback_buffer[MAXPUSHBACK];
int pushback_index = 0;
int
lgetc(int quotec)
{
int c, next;
if (parsebuf) {
/* Read character from the parsebuffer instead of input. */
if (parseindex >= 0) {
c = parsebuf[parseindex++];
if (c != '\0')
return (c);
parsebuf = NULL;
} else
parseindex++;
}
if (pushback_index)
return (pushback_buffer[--pushback_index]);
if (quotec) {
if ((c = getc(file->stream)) == EOF) {
yyerror("reached end of file while parsing quoted string");
if (file == topfile || popfile() == EOF)
return (EOF);
return (quotec);
}
return (c);
}
while ((c = getc(file->stream)) == '\\') {
next = getc(file->stream);
if (next != '\n') {
c = next;
break;
}
yylval.lineno = file->lineno;
file->lineno++;
}
if (c == '\t' || c == ' ') {
/* Compress blanks to a single space. */
do {
c = getc(file->stream);
} while (c == '\t' || c == ' ');
ungetc(c, file->stream);
c = ' ';
}
while (c == EOF) {
if (file == topfile || popfile() == EOF)
return (EOF);
c = getc(file->stream);
}
return (c);
}
int
lungetc(int c)
{
if (c == EOF)
return (EOF);
if (parsebuf) {
parseindex--;
if (parseindex >= 0)
return (c);
}
if (pushback_index < MAXPUSHBACK-1)
return (pushback_buffer[pushback_index++] = c);
else
return (EOF);
}
int
findeol(void)
{
int c;
parsebuf = NULL;
pushback_index = 0;
/* skip to either EOF or the first real EOL */
while (1) {
c = lgetc(0);
if (c == '\n') {
file->lineno++;
break;
}
if (c == EOF)
break;
}
return (ERROR);
}
int
yylex(void)
{
char buf[8096];
char *p, *val;
int quotec, next, c;
int token;
top:
p = buf;
while ((c = lgetc(0)) == ' ' || c == '\t')
; /* nothing */
yylval.lineno = file->lineno;
if (c == '#')
while ((c = lgetc(0)) != '\n' && c != EOF)
; /* nothing */
if (c == '$' && parsebuf == NULL) {
while (1) {
if ((c = lgetc(0)) == EOF)
return (0);
if (p + 1 >= buf + sizeof(buf) - 1) {
yyerror("string too long");
return (findeol());
}
if (isalnum(c) || c == '_') {
*p++ = (char)c;
continue;
}
*p = '\0';
lungetc(c);
break;
}
val = symget(buf);
if (val == NULL) {
yyerror("macro '%s' not defined", buf);
return (findeol());
}
parsebuf = val;
parseindex = 0;
goto top;
}
switch (c) {
case '\'':
case '"':
quotec = c;
while (1) {
if ((c = lgetc(quotec)) == EOF)
return (0);
if (c == '\n') {
file->lineno++;
continue;
} else if (c == '\\') {
if ((next = lgetc(quotec)) == EOF)
return (0);
if (next == quotec || c == ' ' || c == '\t')
c = next;
else if (next == '\n')
continue;
else
lungetc(next);
} else if (c == quotec) {
*p = '\0';
break;
}
if (p + 1 >= buf + sizeof(buf) - 1) {
yyerror("string too long");
return (findeol());
}
*p++ = (char)c;
}
yylval.v.string = strdup(buf);
if (yylval.v.string == NULL)
err(1, "yylex: strdup");
return (STRING);
}
#define allowed_to_end_number(x) \
(isspace(x) || x == ')' || x ==',' || x == '/' || x == '}' || x == '=')
if (c == '-' || isdigit(c)) {
do {
*p++ = c;
if ((unsigned)(p-buf) >= sizeof(buf)) {
yyerror("string too long");
return (findeol());
}
} while ((c = lgetc(0)) != EOF && isdigit(c));
lungetc(c);
if (p == buf + 1 && buf[0] == '-')
goto nodigits;
if (c == EOF || allowed_to_end_number(c)) {
const char *errstr = NULL;
*p = '\0';
yylval.v.number = strtonum(buf, LLONG_MIN,
LLONG_MAX, &errstr);
if (errstr) {
yyerror("\"%s\" invalid number: %s",
buf, errstr);
return (findeol());
}
return (NUMBER);
} else {
nodigits:
while (p > buf + 1)
lungetc(*--p);
c = *--p;
if (c == '-')
return (c);
}
}
#define allowed_in_string(x) \
(isalnum(x) || (ispunct(x) && x != '(' && x != ')' && \
x != '{' && x != '}' && \
x != '!' && x != '=' && x != '#' && \
x != ','))
if (isalnum(c) || c == ':' || c == '_') {
do {
*p++ = c;
if ((unsigned)(p-buf) >= sizeof(buf)) {
yyerror("string too long");
return (findeol());
}
} while ((c = lgetc(0)) != EOF && (allowed_in_string(c)));
lungetc(c);
*p = '\0';
if ((token = lookup(buf)) == STRING)
if ((yylval.v.string = strdup(buf)) == NULL)
err(1, "yylex: strdup");
return (token);
}
if (c == '\n') {
yylval.lineno = file->lineno;
file->lineno++;
}
if (c == EOF)
return (0);
return (c);
}
int
check_file_secrecy(int fd, const char *fname)
{
struct stat st;
if (fstat(fd, &st)) {
log_warn("cannot stat %s", fname);
return (-1);
}
if (st.st_uid != 0 && st.st_uid != getuid()) {
log_warnx("%s: owner not root or current user", fname);
return (-1);
}
if (st.st_mode & (S_IRWXG | S_IRWXO)) {
log_warnx("%s: group/world readable/writeable", fname);
return (-1);
}
return (0);
}
struct file *
pushfile(const char *name, int secret)
{
struct file *nfile;
if ((nfile = calloc(1, sizeof(struct file))) == NULL ||
(nfile->name = strdup(name)) == NULL) {
log_warn("malloc");
return (NULL);
}
if ((nfile->stream = fopen(nfile->name, "r")) == NULL) {
log_warn("%s", nfile->name);
free(nfile->name);
free(nfile);
return (NULL);
} else if (secret &&
check_file_secrecy(fileno(nfile->stream), nfile->name)) {
fclose(nfile->stream);
free(nfile->name);
free(nfile);
return (NULL);
}
nfile->lineno = 1;
TAILQ_INSERT_TAIL(&files, nfile, entry);
return (nfile);
}
int
popfile(void)
{
struct file *prev;
if ((prev = TAILQ_PREV(file, files, entry)) != NULL)
prev->errors += file->errors;
TAILQ_REMOVE(&files, file, entry);
fclose(file->stream);
free(file->name);
free(file);
file = prev;
return (file ? 0 : EOF);
}
struct snmpd *
parse_config(const char *filename, u_int flags)
{
struct sym *sym, *next;
if ((conf = calloc(1, sizeof(*conf))) == NULL) {
log_warn("cannot allocate memory");
return (NULL);
}
conf->sc_flags = flags;
conf->sc_confpath = filename;
conf->sc_address.ss.ss_family = AF_INET;
conf->sc_address.port = SNMPD_PORT;
strlcpy(conf->sc_rdcommunity, "public", SNMPD_MAXCOMMUNITYLEN);
strlcpy(conf->sc_rwcommunity, "private", SNMPD_MAXCOMMUNITYLEN);
strlcpy(conf->sc_trcommunity, "public", SNMPD_MAXCOMMUNITYLEN);
TAILQ_INIT(&conf->sc_trapreceivers);
if ((file = pushfile(filename, 0)) == NULL) {
free(conf);
return (NULL);
}
topfile = file;
setservent(1);
yyparse();
errors = file->errors;
popfile();
endservent();
/* Free macros and check which have not been used. */
for (sym = TAILQ_FIRST(&symhead); sym != NULL; sym = next) {
next = TAILQ_NEXT(sym, entry);
if ((conf->sc_flags & SNMPD_F_VERBOSE) && !sym->used)
fprintf(stderr, "warning: macro '%s' not "
"used\n", sym->nam);
if (!sym->persist) {
free(sym->nam);
free(sym->val);
TAILQ_REMOVE(&symhead, sym, entry);
free(sym);
}
}
if (errors) {
free(conf);
return (NULL);
}
return (conf);
}
int
symset(const char *nam, const char *val, int persist)
{
struct sym *sym;
for (sym = TAILQ_FIRST(&symhead); sym && strcmp(nam, sym->nam);
sym = TAILQ_NEXT(sym, entry))
; /* nothing */
if (sym != NULL) {
if (sym->persist == 1)
return (0);
else {
free(sym->nam);
free(sym->val);
TAILQ_REMOVE(&symhead, sym, entry);
free(sym);
}
}
if ((sym = calloc(1, sizeof(*sym))) == NULL)
return (-1);
sym->nam = strdup(nam);
if (sym->nam == NULL) {
free(sym);
return (-1);
}
sym->val = strdup(val);
if (sym->val == NULL) {
free(sym->nam);
free(sym);
return (-1);
}
sym->used = 0;
sym->persist = persist;
TAILQ_INSERT_TAIL(&symhead, sym, entry);
return (0);
}
int
cmdline_symset(char *s)
{
char *sym, *val;
int ret;
size_t len;
if ((val = strrchr(s, '=')) == NULL)
return (-1);
len = strlen(s) - strlen(val) + 1;
if ((sym = malloc(len)) == NULL)
errx(1, "cmdline_symset: malloc");
(void)strlcpy(sym, s, len);
ret = symset(sym, val + 1, 1);
free(sym);
return (ret);
}
char *
symget(const char *nam)
{
struct sym *sym;
TAILQ_FOREACH(sym, &symhead, entry)
if (strcmp(nam, sym->nam) == 0) {
sym->used = 1;
return (sym->val);
}
return (NULL);
}
struct address *
host_v4(const char *s)
{
struct in_addr ina;
struct sockaddr_in *sain;
struct address *h;
bzero(&ina, sizeof(ina));
if (inet_pton(AF_INET, s, &ina) != 1)
return (NULL);
if ((h = calloc(1, sizeof(*h))) == NULL)
fatal(NULL);
sain = (struct sockaddr_in *)&h->ss;
sain->sin_len = sizeof(struct sockaddr_in);
sain->sin_family = AF_INET;
sain->sin_addr.s_addr = ina.s_addr;
return (h);
}
struct address *
host_v6(const char *s)
{
struct in6_addr ina6;
struct sockaddr_in6 *sin6;
struct address *h;
bzero(&ina6, sizeof(ina6));
if (inet_pton(AF_INET6, s, &ina6) != 1)
return (NULL);
if ((h = calloc(1, sizeof(*h))) == NULL)
fatal(NULL);
sin6 = (struct sockaddr_in6 *)&h->ss;
sin6->sin6_len = sizeof(struct sockaddr_in6);
sin6->sin6_family = AF_INET6;
memcpy(&sin6->sin6_addr, &ina6, sizeof(ina6));
return (h);
}
int
host_dns(const char *s, struct addresslist *al, int max,
in_port_t port, struct ber_oid *oid, char *cmn)
{
struct addrinfo hints, *res0, *res;
int error, cnt = 0;
struct sockaddr_in *sain;
struct sockaddr_in6 *sin6;
struct address *h;
bzero(&hints, sizeof(hints));
hints.ai_family = PF_UNSPEC;
hints.ai_socktype = SOCK_DGRAM; /* DUMMY */
error = getaddrinfo(s, NULL, &hints, &res0);
if (error == EAI_AGAIN || error == EAI_NODATA || error == EAI_NONAME)
return (0);
if (error) {
log_warnx("host_dns: could not parse \"%s\": %s", s,
gai_strerror(error));
return (-1);
}
for (res = res0; res && cnt < max; res = res->ai_next) {
if (res->ai_family != AF_INET &&
res->ai_family != AF_INET6)
continue;
if ((h = calloc(1, sizeof(*h))) == NULL)
fatal(NULL);
h->port = port;
if (oid != NULL) {
if ((h->sa_oid = calloc(1, sizeof(*oid))) == NULL)
fatal(NULL);
bcopy(oid, h->sa_oid, sizeof(*oid));
}
if (cmn != NULL) {
if ((h->sa_community = strdup(cmn)) == NULL)
fatal(NULL);
}
h->ss.ss_family = res->ai_family;
if (res->ai_family == AF_INET) {
sain = (struct sockaddr_in *)&h->ss;
sain->sin_len = sizeof(struct sockaddr_in);
sain->sin_addr.s_addr = ((struct sockaddr_in *)
res->ai_addr)->sin_addr.s_addr;
} else {
sin6 = (struct sockaddr_in6 *)&h->ss;
sin6->sin6_len = sizeof(struct sockaddr_in6);
memcpy(&sin6->sin6_addr, &((struct sockaddr_in6 *)
res->ai_addr)->sin6_addr, sizeof(struct in6_addr));
}
TAILQ_INSERT_HEAD(al, h, entry);
cnt++;
}
if (cnt == max && res) {
log_warnx("host_dns: %s resolves to more than %d hosts",
s, max);
}
freeaddrinfo(res0);
if (oid != NULL)
free(oid);
if (cmn != NULL)
free(cmn);
return (cnt);
}
int
host(const char *s, struct addresslist *al, int max,
in_port_t port, struct ber_oid *oid, char *cmn)
{
struct address *h;
h = host_v4(s);
/* IPv6 address? */
if (h == NULL)
h = host_v6(s);
if (h != NULL) {
h->port = port;
h->sa_oid = oid;
h->sa_community = cmn;
TAILQ_INSERT_HEAD(al, h, entry);
return (1);
}
return (host_dns(s, al, max, port, oid, cmn));
}