%{
#include <sys/types.h>
#include <sys/queue.h>
#include <sys/socket.h>
#include <sys/stat.h>
#include <net/if.h>
#include <netinet/in.h>
#include <arpa/inet.h>
#include <ctype.h>
#include <err.h>
#include <errno.h>
#include <event.h>
#include <imsg.h>
#include <limits.h>
#include <stdarg.h>
#include <stdio.h>
#include <string.h>
#include <syslog.h>
#include <unistd.h>
#include <vis.h>
#include "log.h"
#include "dhcp6leased.h"
#include "frontend.h"
TAILQ_HEAD(files, file) files = TAILQ_HEAD_INITIALIZER(files);
struct file *file, *topfile;
int check_file_secrecy(int, const char *);
int yyparse(void);
int yylex(void);
int yyerror(const char *, ...)
__attribute__((__format__ (printf, 1, 2)))
__attribute__((__nonnull__ (1)));
int lookup(char *);
int igetc(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 *);
static struct dhcp6leased_conf *conf;
static int errors;
static struct iface_conf *iface_conf;
static struct iface_ia_conf *iface_ia_conf;
struct iface_conf *conf_get_iface(char *);
struct iface_pd_conf *conf_get_pd_iface(char *, int);
void addressing_plan(struct iface_ia_conf *);
int fls64(uint64_t);
typedef struct {
union {
int64_t number;
char *string;
} v;
int lineno;
} YYSTYPE;
%}
%token ERROR DELEGATION FOR ON PREFIX REQUEST RAPID COMMIT
%token <v.string> STRING
%token <v.number> NUMBER
%type <v.string> string
%%
grammar :
| grammar '\n'
| grammar varset '\n'
| grammar conf_main '\n'
| grammar ia_pd '\n'
| grammar error '\n' { file->errors++; }
;
string : string STRING {
if (asprintf(&$$, "%s %s", $1, $2) == -1) {
free($1);
free($2);
yyerror("string: asprintf");
YYERROR;
}
free($1);
free($2);
}
| STRING
;
varset : STRING '=' string {
char *s = $1;
if (log_getverbose() == 1)
printf("%s = \"%s\"\n", $1, $3);
while (*s++) {
if (isspace((unsigned char)*s)) {
yyerror("macro name cannot contain "
"whitespace");
free($1);
free($3);
YYERROR;
}
}
if (symset($1, $3, 0) == -1)
fatal("cannot store variable");
free($1);
free($3);
}
;
optnl : '\n' optnl
|
;
conf_main : REQUEST RAPID COMMIT {
conf->rapid_commit = 1;
}
;
ia_pd : REQUEST PREFIX DELEGATION ON STRING FOR {
iface_conf = conf_get_iface($5);
iface_ia_conf = calloc(1, sizeof(*iface_ia_conf));
if (iface_ia_conf == NULL)
err(1, "%s: calloc", __func__);
iface_ia_conf->id = iface_conf->ia_count++;
if (iface_conf->ia_count > MAX_IA) {
yyerror("Too many prefix delegation requests");
YYERROR;
}
SIMPLEQ_INIT(&iface_ia_conf->iface_pd_list);
SIMPLEQ_INSERT_TAIL(&iface_conf->iface_ia_list,
iface_ia_conf, entry);
} iface_block {
iface_conf = NULL;
iface_ia_conf = NULL;
}
;
iface_block : '{' optnl ifaceopts_l '}'
| ifaceoptsl
;
ifaceopts_l : ifaceopts_l ifaceoptsl optnl
| ifaceoptsl optnl
;
ifaceoptsl : STRING {
struct iface_pd_conf *iface_pd_conf;
int prefixlen;
char *p;
const char *errstr;
p = strchr($1, '/');
if (p != NULL) {
*p++ = '\0';
prefixlen = strtonum(p, 0, 128, &errstr);
if (errstr != NULL) {
yyerror("error parsing interface "
"\"%s/%s\"", $1, p);
free($1);
YYERROR;
}
} else
prefixlen = 64;
if ((iface_pd_conf = conf_get_pd_iface($1, prefixlen))
== NULL) {
yyerror("duplicate interface %s", $1);
free($1);
YYERROR;
}
}
;
%%
struct keywords {
const char *k_name;
int k_val;
};
int
yyerror(const char *fmt, ...)
{
va_list ap;
char *msg;
file->errors++;
va_start(ap, fmt);
if (vasprintf(&msg, fmt, ap) == -1)
fatalx("yyerror vasprintf");
va_end(ap);
logit(LOG_CRIT, "%s:%d: %s", file->name, yylval.lineno, msg);
free(msg);
return (0);
}
int
kw_cmp(const void *k, const void *e)
{
return (strcmp(k, ((const struct keywords *)e)->k_name));
}
int
lookup(char *s)
{
static const struct keywords keywords[] = {
{"commit", COMMIT},
{"delegation", DELEGATION},
{"for", FOR},
{"on", ON},
{"prefix", PREFIX},
{"rapid", RAPID},
{"request", REQUEST},
};
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 START_EXPAND 1
#define DONE_EXPAND 2
static int expanding;
int
igetc(void)
{
int c;
while (1) {
if (file->ungetpos > 0)
c = file->ungetbuf[--file->ungetpos];
else
c = getc(file->stream);
if (c == START_EXPAND)
expanding = 1;
else if (c == DONE_EXPAND)
expanding = 0;
else
break;
}
return (c);
}
int
lgetc(int quotec)
{
int c, next;
if (quotec) {
if ((c = igetc()) == EOF) {
yyerror("reached end of file while parsing "
"quoted string");
if (file == topfile || popfile() == EOF)
return (EOF);
return (quotec);
}
return (c);
}
while ((c = igetc()) == '\\') {
next = igetc();
if (next != '\n') {
c = next;
break;
}
yylval.lineno = file->lineno;
file->lineno++;
}
if (c == EOF) {
if (file->eof_reached == 0) {
file->eof_reached = 1;
return ('\n');
}
while (c == EOF) {
if (file == topfile || popfile() == EOF)
return (EOF);
c = igetc();
}
}
return (c);
}
void
lungetc(int c)
{
if (c == EOF)
return;
if (file->ungetpos >= file->ungetsize) {
void *p = reallocarray(file->ungetbuf, file->ungetsize, 2);
if (p == NULL)
err(1, "lungetc");
file->ungetbuf = p;
file->ungetsize *= 2;
}
file->ungetbuf[file->ungetpos++] = c;
}
int
findeol(void)
{
int c;
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')
;
yylval.lineno = file->lineno;
if (c == '#')
while ((c = lgetc(0)) != '\n' && c != EOF)
;
if (c == '$' && !expanding) {
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++ = c;
continue;
}
*p = '\0';
lungetc(c);
break;
}
val = symget(buf);
if (val == NULL) {
yyerror("macro '%s' not defined", buf);
return (findeol());
}
p = val + strlen(val) - 1;
lungetc(DONE_EXPAND);
while (p >= val) {
lungetc((unsigned char)*p);
p--;
}
lungetc(START_EXPAND);
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 || next == ' ' ||
next == '\t')
c = next;
else if (next == '\n') {
file->lineno++;
continue;
} else
lungetc(next);
} else if (c == quotec) {
*p = '\0';
break;
} else if (c == '\0') {
yyerror("syntax error");
return (findeol());
}
if (p + 1 >= buf + sizeof(buf) - 1) {
yyerror("string too long");
return (findeol());
}
*p++ = 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 ((size_t)(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((unsigned char)*--p);
c = (unsigned char)*--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 ((size_t)(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_IWGRP | S_IXGRP | S_IRWXO)) {
log_warnx("%s: group writable or world read/writable", fname);
return (-1);
}
return (0);
}
struct file *
pushfile(const char *name, int secret)
{
struct file *nfile;
if ((nfile = calloc(1, sizeof(struct file))) == NULL) {
log_warn("calloc");
return (NULL);
}
if ((nfile->name = strdup(name)) == NULL) {
log_warn("strdup");
free(nfile);
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 = TAILQ_EMPTY(&files) ? 1 : 0;
nfile->ungetsize = 16;
nfile->ungetbuf = malloc(nfile->ungetsize);
if (nfile->ungetbuf == NULL) {
log_warn("malloc");
fclose(nfile->stream);
free(nfile->name);
free(nfile);
return (NULL);
}
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->ungetbuf);
free(file);
file = prev;
return (file ? 0 : EOF);
}
struct dhcp6leased_conf *
parse_config(const char *filename)
{
struct sym *sym, *next;
struct iface_conf *iface;
struct iface_ia_conf *ia_conf;
conf = config_new_empty();
file = pushfile(filename, 0);
if (file == NULL) {
free(conf);
return (NULL);
}
topfile = file;
yyparse();
errors = file->errors;
popfile();
TAILQ_FOREACH_SAFE(sym, &symhead, entry, next) {
if ((log_getverbose() == 2) && !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) {
config_clear(conf);
return (NULL);
}
SIMPLEQ_FOREACH(iface, &conf->iface_list, entry) {
SIMPLEQ_FOREACH(ia_conf, &iface->iface_ia_list, entry) {
addressing_plan(ia_conf);
}
}
return (conf);
}
int
symset(const char *nam, const char *val, int persist)
{
struct sym *sym;
TAILQ_FOREACH(sym, &symhead, entry) {
if (strcmp(nam, sym->nam) == 0)
break;
}
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);
}
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 iface_conf *
conf_get_iface(char *name)
{
struct iface_conf *iface;
size_t n;
SIMPLEQ_FOREACH(iface, &conf->iface_list, entry) {
if (strcmp(name, iface->name) == 0)
return (iface);
}
iface = calloc(1, sizeof(*iface));
if (iface == NULL)
errx(1, "%s: calloc", __func__);
n = strlcpy(iface->name, name, sizeof(iface->name));
if (n >= sizeof(iface->name))
errx(1, "%s: name too long", __func__);
SIMPLEQ_INIT(&iface->iface_ia_list);
SIMPLEQ_INSERT_TAIL(&conf->iface_list, iface, entry);
return (iface);
}
struct iface_pd_conf *
conf_get_pd_iface(char *name, int prefixlen)
{
struct iface_ia_conf *iface_ia;
struct iface_pd_conf *iface_pd;
size_t n;
if (strcmp(name, "reserve") != 0) {
SIMPLEQ_FOREACH(iface_ia, &iface_conf->iface_ia_list,
entry) {
SIMPLEQ_FOREACH(iface_pd, &iface_ia->iface_pd_list,
entry) {
if (strcmp(name, iface_pd->name) == 0)
return NULL;
}
}
}
iface_pd = calloc(1, sizeof(*iface_pd));
if (iface_pd == NULL)
err(1, "%s: calloc", __func__);
n = strlcpy(iface_pd->name, name, sizeof(iface_pd->name));
if (n >= sizeof(iface_pd->name))
errx(1, "%s: name too long", __func__);
iface_pd->prefix_len = prefixlen;
SIMPLEQ_INSERT_TAIL(&iface_ia_conf->iface_pd_list, iface_pd, entry);
return (iface_pd);
}
static inline uint64_t
get_shift(int plen)
{
if (plen > 64)
plen -= 64;
return 1ULL << (64 - plen);
}
void
addressing_plan(struct iface_ia_conf *ia_conf)
{
struct iface_pd_conf *pd_conf;
uint64_t *p, lo_counter, hi_counter, lo_shift, hi_shift;
int prev_plen = -1;
lo_counter = hi_counter = 0;
SIMPLEQ_FOREACH(pd_conf, &ia_conf->iface_pd_list, entry) {
if (ia_conf->prefix_len != 0) {
lo_shift = hi_shift = 0;
if (prev_plen > pd_conf->prefix_len) {
if (pd_conf->prefix_len > 64)
lo_shift =
get_shift(pd_conf->prefix_len);
else
hi_shift =
get_shift(pd_conf->prefix_len);
} else {
if (prev_plen > 64)
lo_shift = get_shift(prev_plen);
else
hi_shift = get_shift(prev_plen);
}
if (lo_shift != 0) {
if (lo_counter > UINT64_MAX - lo_shift) {
hi_counter++;
lo_counter = 0;
} else {
lo_counter += lo_shift;
lo_counter &= ~(lo_shift - 1);
}
} else {
hi_counter += hi_shift;
hi_counter &= ~(hi_shift - 1);
lo_counter = 0;
}
} else
ia_conf->prefix_len = pd_conf->prefix_len;
p = (uint64_t *)&pd_conf->prefix_mask.s6_addr;
*p |= htobe64(hi_counter);
p = (uint64_t *)&pd_conf->prefix_mask.s6_addr[8];
*p |= htobe64(lo_counter);
prev_plen = pd_conf->prefix_len;
}
if (hi_counter != 0)
ia_conf->prefix_len = 64 - fls64(hi_counter);
else if (lo_counter != 0)
ia_conf->prefix_len = 128 - fls64(lo_counter);
}
int
fls64(uint64_t _n)
{
int _v;
if (!_n)
return 0;
_v = 64;
if ((_n & 0xFFFFFFFF00000000ULL) == 0) {
_n <<= 32;
_v -= 32;
}
if ((_n & 0xFFFF000000000000ULL) == 0) {
_n <<= 16;
_v -= 16;
}
if ((_n & 0xFF00000000000000ULL) == 0) {
_n <<= 8;
_v -= 8;
}
if ((_n & 0xF000000000000000ULL) == 0) {
_n <<= 4;
_v -= 4;
}
if ((_n & 0xC000000000000000ULL) == 0) {
_n <<= 2;
_v -= 2;
}
if ((_n & 0x8000000000000000ULL) == 0) {
_v -= 1;
}
return _v;
}
