mirror of
https://github.com/slicer69/doas
synced 2024-07-09 03:55:50 +00:00
91622fcbb1
users to perform commands without successful commands being logged to syslogd. Added documentation to doas.conf manual page and doas.conf.sample files to include tips and and example of the "nolog" flag in action. The "nolog" flag is a feature of OpenBSD's doas command and has been introduced for compatibility and as an optional way to avoid filling up system logs with successful doas calls.
348 lines
6.8 KiB
Plaintext
348 lines
6.8 KiB
Plaintext
/* $OpenBSD: parse.y,v 1.26 2017/01/02 01:40:20 tedu Exp $ */
|
|
/*
|
|
* Copyright (c) 2015 Ted Unangst <tedu@openbsd.org>
|
|
*
|
|
* 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 <ctype.h>
|
|
#include <unistd.h>
|
|
#include <stdint.h>
|
|
#include <stdarg.h>
|
|
#include <stdio.h>
|
|
#include <stdlib.h>
|
|
#include <string.h>
|
|
#include <err.h>
|
|
|
|
#include "doas.h"
|
|
|
|
typedef struct {
|
|
union {
|
|
struct {
|
|
int action;
|
|
int options;
|
|
const char *cmd;
|
|
const char **cmdargs;
|
|
const char **envlist;
|
|
};
|
|
const char **strlist;
|
|
const char *str;
|
|
};
|
|
int lineno;
|
|
int colno;
|
|
} yystype;
|
|
#define YYSTYPE yystype
|
|
|
|
FILE *yyfp;
|
|
|
|
struct rule **rules;
|
|
size_t nrules = 0;
|
|
static size_t maxrules = 0;
|
|
|
|
int parse_errors = 0;
|
|
|
|
static void yyerror(const char *, ...);
|
|
static int yylex(void);
|
|
|
|
static size_t
|
|
arraylen(const char **arr)
|
|
{
|
|
size_t cnt = 0;
|
|
|
|
while (*arr) {
|
|
cnt++;
|
|
arr++;
|
|
}
|
|
return cnt;
|
|
}
|
|
|
|
%}
|
|
|
|
%token TPERMIT TDENY TAS TCMD TARGS
|
|
%token TNOPASS TNOLOG TPERSIST TKEEPENV TSETENV
|
|
%token TSTRING
|
|
|
|
%%
|
|
|
|
grammar: /* empty */
|
|
| grammar '\n'
|
|
| grammar rule '\n'
|
|
| error '\n'
|
|
;
|
|
|
|
rule: action ident target cmd {
|
|
struct rule *r;
|
|
r = calloc(1, sizeof(*r));
|
|
if (!r)
|
|
errx(1, "can't allocate rule");
|
|
r->action = $1.action;
|
|
r->options = $1.options;
|
|
r->envlist = $1.envlist;
|
|
r->ident = $2.str;
|
|
r->target = $3.str;
|
|
r->cmd = $4.cmd;
|
|
r->cmdargs = $4.cmdargs;
|
|
if (nrules == maxrules) {
|
|
if (maxrules == 0)
|
|
maxrules = 32;
|
|
else
|
|
maxrules *= 2;
|
|
if (!(rules = reallocarray(rules, maxrules,
|
|
sizeof(*rules))))
|
|
errx(1, "can't allocate rules");
|
|
}
|
|
rules[nrules++] = r;
|
|
} ;
|
|
|
|
action: TPERMIT options {
|
|
$$.action = PERMIT;
|
|
$$.options = $2.options;
|
|
$$.envlist = $2.envlist;
|
|
} | TDENY {
|
|
$$.action = DENY;
|
|
$$.options = 0;
|
|
$$.envlist = NULL;
|
|
} ;
|
|
|
|
options: /* none */ {
|
|
$$.options = 0;
|
|
$$.envlist = NULL;
|
|
} | options option {
|
|
$$.options = $1.options | $2.options;
|
|
$$.envlist = $1.envlist;
|
|
if (($$.options & (NOPASS|PERSIST)) == (NOPASS|PERSIST)) {
|
|
yyerror("can't combine nopass and persist");
|
|
YYERROR;
|
|
}
|
|
if ($2.envlist) {
|
|
if ($$.envlist) {
|
|
yyerror("can't have two setenv sections");
|
|
YYERROR;
|
|
} else
|
|
$$.envlist = $2.envlist;
|
|
}
|
|
} ;
|
|
option: TNOPASS {
|
|
$$.options = NOPASS;
|
|
$$.envlist = NULL;
|
|
} | TNOLOG {
|
|
$$.options = NOLOG;
|
|
$$.envlist = NULL;
|
|
} | TPERSIST {
|
|
$$.options = PERSIST;
|
|
$$.envlist = NULL;
|
|
} | TKEEPENV {
|
|
$$.options = KEEPENV;
|
|
$$.envlist = NULL;
|
|
} | TSETENV '{' strlist '}' {
|
|
$$.options = 0;
|
|
$$.envlist = $3.strlist;
|
|
} ;
|
|
|
|
strlist: /* empty */ {
|
|
if (!($$.strlist = calloc(1, sizeof(char *))))
|
|
errx(1, "can't allocate strlist");
|
|
} | strlist TSTRING {
|
|
int nstr = arraylen($1.strlist);
|
|
if (!($$.strlist = reallocarray($1.strlist, nstr + 2,
|
|
sizeof(char *))))
|
|
errx(1, "can't allocate strlist");
|
|
$$.strlist[nstr] = $2.str;
|
|
$$.strlist[nstr + 1] = NULL;
|
|
} ;
|
|
|
|
|
|
ident: TSTRING {
|
|
$$.str = $1.str;
|
|
} ;
|
|
|
|
target: /* optional */ {
|
|
$$.str = NULL;
|
|
} | TAS TSTRING {
|
|
$$.str = $2.str;
|
|
} ;
|
|
|
|
cmd: /* optional */ {
|
|
$$.cmd = NULL;
|
|
$$.cmdargs = NULL;
|
|
} | TCMD TSTRING args {
|
|
$$.cmd = $2.str;
|
|
$$.cmdargs = $3.cmdargs;
|
|
} ;
|
|
|
|
args: /* empty */ {
|
|
$$.cmdargs = NULL;
|
|
} | TARGS strlist {
|
|
$$.cmdargs = $2.strlist;
|
|
} ;
|
|
|
|
%%
|
|
|
|
void
|
|
yyerror(const char *fmt, ...)
|
|
{
|
|
va_list va;
|
|
|
|
fprintf(stderr, "doas: ");
|
|
va_start(va, fmt);
|
|
vfprintf(stderr, fmt, va);
|
|
va_end(va);
|
|
fprintf(stderr, " at line %d\n", yylval.lineno + 1);
|
|
parse_errors++;
|
|
}
|
|
|
|
static struct keyword {
|
|
const char *word;
|
|
int token;
|
|
} keywords[] = {
|
|
{ "deny", TDENY },
|
|
{ "permit", TPERMIT },
|
|
{ "as", TAS },
|
|
{ "cmd", TCMD },
|
|
{ "args", TARGS },
|
|
{ "nopass", TNOPASS },
|
|
{ "nolog", TNOLOG },
|
|
{ "persist", TPERSIST },
|
|
{ "keepenv", TKEEPENV },
|
|
{ "setenv", TSETENV },
|
|
};
|
|
|
|
int
|
|
yylex(void)
|
|
{
|
|
char buf[1024], *ebuf, *p, *str;
|
|
int i, c, quotes = 0, escape = 0, qpos = -1, nonkw = 0;
|
|
|
|
p = buf;
|
|
ebuf = buf + sizeof(buf);
|
|
|
|
repeat:
|
|
/* skip whitespace first */
|
|
for (c = getc(yyfp); c == ' ' || c == '\t'; c = getc(yyfp))
|
|
yylval.colno++;
|
|
|
|
/* check for special one-character constructions */
|
|
switch (c) {
|
|
case '\n':
|
|
yylval.colno = 0;
|
|
yylval.lineno++;
|
|
/* FALLTHROUGH */
|
|
case '{':
|
|
case '}':
|
|
return c;
|
|
case '#':
|
|
/* skip comments; NUL is allowed; no continuation */
|
|
while ((c = getc(yyfp)) != '\n')
|
|
if (c == EOF)
|
|
goto eof;
|
|
yylval.colno = 0;
|
|
yylval.lineno++;
|
|
return c;
|
|
case EOF:
|
|
goto eof;
|
|
}
|
|
|
|
/* parsing next word */
|
|
for (;; c = getc(yyfp), yylval.colno++) {
|
|
switch (c) {
|
|
case '\0':
|
|
yyerror("unallowed character NUL in column %d",
|
|
yylval.colno + 1);
|
|
escape = 0;
|
|
continue;
|
|
case '\\':
|
|
escape = !escape;
|
|
if (escape)
|
|
continue;
|
|
break;
|
|
case '\n':
|
|
if (quotes)
|
|
yyerror("unterminated quotes in column %d",
|
|
qpos + 1);
|
|
if (escape) {
|
|
nonkw = 1;
|
|
escape = 0;
|
|
yylval.colno = 0;
|
|
yylval.lineno++;
|
|
continue;
|
|
}
|
|
goto eow;
|
|
case EOF:
|
|
if (escape)
|
|
yyerror("unterminated escape in column %d",
|
|
yylval.colno);
|
|
if (quotes)
|
|
yyerror("unterminated quotes in column %d",
|
|
qpos + 1);
|
|
goto eow;
|
|
/* FALLTHROUGH */
|
|
case '{':
|
|
case '}':
|
|
case '#':
|
|
case ' ':
|
|
case '\t':
|
|
if (!escape && !quotes)
|
|
goto eow;
|
|
break;
|
|
case '"':
|
|
if (!escape) {
|
|
quotes = !quotes;
|
|
if (quotes) {
|
|
nonkw = 1;
|
|
qpos = yylval.colno;
|
|
}
|
|
continue;
|
|
}
|
|
}
|
|
*p++ = c;
|
|
if (p == ebuf) {
|
|
yyerror("too long line");
|
|
p = buf;
|
|
}
|
|
escape = 0;
|
|
}
|
|
|
|
eow:
|
|
*p = 0;
|
|
if (c != EOF)
|
|
ungetc(c, yyfp);
|
|
if (p == buf) {
|
|
/*
|
|
* There could be a number of reasons for empty buffer,
|
|
* and we handle all of them here, to avoid cluttering
|
|
* the main loop.
|
|
*/
|
|
if (c == EOF)
|
|
goto eof;
|
|
else if (qpos == -1) /* accept, e.g., empty args: cmd foo args "" */
|
|
goto repeat;
|
|
}
|
|
if (!nonkw) {
|
|
for (i = 0; i < sizeof(keywords) / sizeof(keywords[0]); i++) {
|
|
if (strcmp(buf, keywords[i].word) == 0)
|
|
return keywords[i].token;
|
|
}
|
|
}
|
|
if ((str = strdup(buf)) == NULL)
|
|
err(1, "strdup");
|
|
yylval.str = str;
|
|
return TSTRING;
|
|
|
|
eof:
|
|
if (ferror(yyfp))
|
|
yyerror("input error reading config");
|
|
return 0;
|
|
}
|