If the reentrant versions of the functions are available, use them so
that libnftables is thread-safe in this regard.
Signed-off-by: Thomas Haller <thaller@xxxxxxxxxx>
---
Changes to v1:
- have nft_getprotobyname() return a negative integer on error or the
non-negative port number.
configure.ac | 4 +++
include/utils.h | 4 +++
src/datatype.c | 32 +++++++++---------
src/json.c | 21 ++++++------
src/rule.c | 6 ++--
src/utils.c | 88 +++++++++++++++++++++++++++++++++++++++++++++++++
6 files changed, 125 insertions(+), 30 deletions(-)
diff --git a/configure.ac b/configure.ac
index b0201ac3528e..42f0dc4cf392 100644
--- a/configure.ac
+++ b/configure.ac
@@ -108,6 +108,10 @@ AC_DEFINE([HAVE_LIBJANSSON], [1], [Define if you have libjansson])
])
AM_CONDITIONAL([BUILD_JSON], [test "x$with_json" != xno])
+AC_CHECK_DECLS([getprotobyname_r, getprotobynumber_r, getservbyport_r], [], [], [[
+#include <netdb.h>
+]])
+
AC_CONFIG_FILES([ \
Makefile \
libnftables.pc \
diff --git a/include/utils.h b/include/utils.h
index d5073e061033..80d57dae87cb 100644
--- a/include/utils.h
+++ b/include/utils.h
@@ -138,4 +138,8 @@ extern char *xstrdup(const char *s);
extern void xstrunescape(const char *in, char *out);
extern int round_pow_2(unsigned int value);
+bool nft_getprotobynumber(int number, char *out_name, size_t name_len);
+int nft_getprotobyname(const char *name);
+bool nft_getservbyport(int port, const char *proto, char *out_name, size_t name_len);
+
#endif /* NFTABLES_UTILS_H */
diff --git a/src/datatype.c b/src/datatype.c
index da802a18bccd..02d5c3ebf9b7 100644
--- a/src/datatype.c
+++ b/src/datatype.c
@@ -697,12 +697,11 @@ const struct datatype ip6addr_type = {
static void inet_protocol_type_print(const struct expr *expr,
struct output_ctx *octx)
{
- struct protoent *p;
-
if (!nft_output_numeric_proto(octx)) {
- p = getprotobynumber(mpz_get_uint8(expr->value));
- if (p != NULL) {
- nft_print(octx, "%s", p->p_name);
+ char name[1024];
+
+ if (nft_getprotobynumber(mpz_get_uint8(expr->value), name, sizeof(name))) {
+ nft_print(octx, "%s", name);
return;
}
}
@@ -711,15 +710,15 @@ static void inet_protocol_type_print(const struct expr *expr,
static void inet_protocol_type_describe(struct output_ctx *octx)
{
- struct protoent *p;
uint8_t protonum;
for (protonum = 0; protonum < UINT8_MAX; protonum++) {
- p = getprotobynumber(protonum);
- if (!p)
+ char name[1024];
+
+ if (!nft_getprotobynumber(protonum, name, sizeof(name)))
continue;
- nft_print(octx, "\t%-30s\t%u\n", p->p_name, protonum);
+ nft_print(octx, "\t%-30s\t%u\n", name, protonum);
}
}
@@ -727,7 +726,6 @@ static struct error_record *inet_protocol_type_parse(struct parse_ctx *ctx,
const struct expr *sym,
struct expr **res)
{
- struct protoent *p;
uint8_t proto;
uintmax_t i;
char *end;
@@ -740,11 +738,13 @@ static struct error_record *inet_protocol_type_parse(struct parse_ctx *ctx,
proto = i;
} else {
- p = getprotobyname(sym->identifier);
- if (p == NULL)
+ int r;
+
+ r = nft_getprotobyname(sym->identifier);
+ if (r < 0)
return error(&sym->location, "Could not resolve protocol name");
- proto = p->p_proto;
+ proto = r;
}
*res = constant_expr_alloc(&sym->location, &inet_protocol_type,
@@ -768,12 +768,12 @@ const struct datatype inet_protocol_type = {
static void inet_service_print(const struct expr *expr, struct output_ctx *octx)
{
uint16_t port = mpz_get_be16(expr->value);
- const struct servent *s = getservbyport(port, NULL);
+ char name[1024];
- if (s == NULL)
+ if (!nft_getservbyport(port, NULL, name, sizeof(name)))
nft_print(octx, "%hu", ntohs(port));
else
- nft_print(octx, "\"%s\"", s->s_name);
+ nft_print(octx, "\"%s\"", name);
}
void inet_service_type_print(const struct expr *expr, struct output_ctx *octx)
diff --git a/src/json.c b/src/json.c
index a119dfc4f1eb..969b44e3004a 100644
--- a/src/json.c
+++ b/src/json.c
@@ -297,10 +297,10 @@ static json_t *chain_print_json(const struct chain *chain)
static json_t *proto_name_json(uint8_t proto)
{
- const struct protoent *p = getprotobynumber(proto);
+ char name[1024];
- if (p)
- return json_string(p->p_name);
+ if (nft_getprotobynumber(proto, name, sizeof(name)))
+ return json_string(name);
return json_integer(proto);
}
@@ -1093,12 +1093,11 @@ json_t *boolean_type_json(const struct expr *expr, struct output_ctx *octx)
json_t *inet_protocol_type_json(const struct expr *expr,
struct output_ctx *octx)
{
- struct protoent *p;
-
if (!nft_output_numeric_proto(octx)) {
- p = getprotobynumber(mpz_get_uint8(expr->value));
- if (p != NULL)
- return json_string(p->p_name);
+ char name[1024];
+
+ if (nft_getprotobynumber(mpz_get_uint8(expr->value), name, sizeof(name)))
+ return json_string(name);
}
return integer_type_json(expr, octx);
}
@@ -1106,13 +1105,13 @@ json_t *inet_protocol_type_json(const struct expr *expr,
json_t *inet_service_type_json(const struct expr *expr, struct output_ctx *octx)
{
uint16_t port = mpz_get_be16(expr->value);
- const struct servent *s = NULL;
+ char name[1024];
if (!nft_output_service(octx) ||
- (s = getservbyport(port, NULL)) == NULL)
+ !nft_getservbyport(port, NULL, name, sizeof(name)))
return json_integer(ntohs(port));
- return json_string(s->s_name);
+ return json_string(name);
}
json_t *mark_type_json(const struct expr *expr, struct output_ctx *octx)
diff --git a/src/rule.c b/src/rule.c
index 99c4f0bb8b00..c32c7303a28e 100644
--- a/src/rule.c
+++ b/src/rule.c
@@ -1666,10 +1666,10 @@ struct obj *obj_lookup_fuzzy(const char *obj_name,
static void print_proto_name_proto(uint8_t l4, struct output_ctx *octx)
{
- const struct protoent *p = getprotobynumber(l4);
+ char name[1024];
- if (p)
- nft_print(octx, "%s", p->p_name);
+ if (nft_getprotobynumber(l4, name, sizeof(name)))
+ nft_print(octx, "%s", name);
else
nft_print(octx, "%d", l4);
}
diff --git a/src/utils.c b/src/utils.c
index a5815018c775..5ab7be8fb323 100644
--- a/src/utils.c
+++ b/src/utils.c
@@ -14,6 +14,7 @@
#include <stdio.h>
#include <unistd.h>
#include <string.h>
+#include <netdb.h>
#include <nftables.h>
#include <utils.h>
@@ -105,3 +106,90 @@ int round_pow_2(unsigned int n)
{
return 1UL << fls(n - 1);
}
+
+bool nft_getprotobynumber(int proto, char *out_name, size_t name_len)
+{
+ const struct protoent *result;
+
+#if HAVE_DECL_GETPROTOBYNUMBER_R
+ struct protoent result_buf;
+ char buf[2048];
+ int r;
+
+ r = getprotobynumber_r(proto,
+ &result_buf,
+ buf,
+ sizeof(buf),
+ (struct protoent **) &result);
+ if (r != 0 || result != &result_buf)
+ result = NULL;
+#else
+ result = getprotobynumber(proto);
+#endif
+
+ if (!result)
+ return false;
+
+ if (strlen(result->p_name) >= name_len)
+ return false;
+ strcpy(out_name, result->p_name);
+ return true;
+}
+
+int nft_getprotobyname(const char *name)
+{
+ const struct protoent *result;
+
+#if HAVE_DECL_GETPROTOBYNAME_R
+ struct protoent result_buf;
+ char buf[2048];
+ int r;
+
+ r = getprotobyname_r(name,
+ &result_buf,
+ buf,
+ sizeof(buf),
+ (struct protoent **) &result);
+ if (r != 0 || result != &result_buf)
+ result = NULL;
+#else
+ result = getprotobyname(name);
+#endif
+
+ if (!result)
+ return -1;
+
+ if (result->p_proto < 0 || result->p_proto > UINT8_MAX)
+ return -1;
+ return (uint8_t) result->p_proto;
+}
+
+bool nft_getservbyport(int port, const char *proto, char *out_name, size_t name_len)
+{
+ const struct servent *result;
+
+#if HAVE_DECL_GETSERVBYPORT_R
+ struct servent result_buf;
+ char buf[2048];
+ int r;
+
+ r = getservbyport_r(port,
+ proto,
+ &result_buf,
+ buf,
+ sizeof(buf),
+ (struct servent**) &result);
+ if (r != 0 || result != &result_buf)
+ result = NULL;
+#else
+ result = getservbyport(port, proto);
+#endif
+
+ if (!result)
+ return false;
+
+ if (strlen(result->s_name) >= name_len)
+ return false;
+ strcpy(out_name, result->s_name);
+ return true;
+}
--
2.41.0
