/*
- * Copyright (c) 2008, 2009, 2010, 2011 Nicira Networks.
+ * Copyright (c) 2008, 2009, 2010, 2011, 2012, 2013 Nicira, Inc.
*
* Licensed under the Apache License, Version 2.0 (the "License");
* you may not use this file except in compliance with the License.
#include <config.h>
#include "netlink.h"
-#include <assert.h>
#include <errno.h>
#include <inttypes.h>
#include <sys/types.h>
#include <unistd.h>
#include "coverage.h"
+#include "flow.h"
#include "netlink-protocol.h"
#include "ofpbuf.h"
#include "timeval.h"
struct nlmsgerr *err = ofpbuf_at(msg, NLMSG_HDRLEN, sizeof *err);
int code = EPROTO;
if (!err) {
- VLOG_ERR_RL(&rl, "received invalid nlmsgerr (%zd bytes < %zd)",
+ VLOG_ERR_RL(&rl, "received invalid nlmsgerr (%"PRIuSIZE"d bytes < %"PRIuSIZE"d)",
msg->size, NLMSG_HDRLEN + sizeof *err);
} else if (err->error <= 0 && err->error > INT_MIN) {
code = -err->error;
ofpbuf_prealloc_tailroom(msg, NLMSG_ALIGN(size));
}
-static uint32_t
-get_nlmsg_seq(void)
-{
- /* Next nlmsghdr sequence number.
- *
- * This implementation uses sequence numbers that are unique process-wide,
- * to avoid a hypothetical race: send request, close socket, open new
- * socket that reuses the old socket's PID value, send request on new
- * socket, receive reply from kernel to old socket but with same PID and
- * sequence number. (This race could be avoided other ways, e.g. by
- * preventing PIDs from being quickly reused). */
- static uint32_t next_seq;
-
- if (next_seq == 0) {
- /* Pick initial sequence number. */
- next_seq = getpid() ^ time_wall();
- }
- return next_seq++;
-}
-
/* Puts a nlmsghdr at the beginning of 'msg', which must be initially empty.
* Uses the given 'type' and 'flags'. 'expected_payload' should be
* an estimate of the number of payload bytes to be supplied; if the size of
* is often NLM_F_REQUEST indicating that a request is being made, commonly
* or'd with NLM_F_ACK to request an acknowledgement.
*
- * Sets the new nlmsghdr's nlmsg_pid field to 0 for now. nl_sock_send() will
- * fill it in just before sending the message.
+ * Sets the new nlmsghdr's nlmsg_len, nlmsg_seq, and nlmsg_pid fields to 0 for
+ * now. Functions that send Netlink messages will fill these in just before
+ * sending the message.
*
* nl_msg_put_genlmsghdr() is more convenient for composing a Generic Netlink
* message. */
{
struct nlmsghdr *nlmsghdr;
- assert(msg->size == 0);
+ ovs_assert(msg->size == 0);
nl_msg_reserve(msg, NLMSG_HDRLEN + expected_payload);
nlmsghdr = nl_msg_put_uninit(msg, NLMSG_HDRLEN);
nlmsghdr->nlmsg_len = 0;
nlmsghdr->nlmsg_type = type;
nlmsghdr->nlmsg_flags = flags;
- nlmsghdr->nlmsg_seq = get_nlmsg_seq();
+ nlmsghdr->nlmsg_seq = 0;
nlmsghdr->nlmsg_pid = 0;
}
struct genlmsghdr *genlmsghdr;
nl_msg_put_nlmsghdr(msg, GENL_HDRLEN + expected_payload, family, flags);
- assert(msg->size == NLMSG_HDRLEN);
+ ovs_assert(msg->size == NLMSG_HDRLEN);
genlmsghdr = nl_msg_put_uninit(msg, GENL_HDRLEN);
genlmsghdr->cmd = cmd;
genlmsghdr->version = version;
{
size_t total_size = NLA_HDRLEN + size;
struct nlattr* nla = nl_msg_put_uninit(msg, total_size);
- assert(NLA_ALIGN(total_size) <= UINT16_MAX);
+ ovs_assert(NLA_ALIGN(total_size) <= UINT16_MAX);
nla->nla_len = total_size;
nla->nla_type = type;
return nla + 1;
}
+/* Appends a Netlink attribute of the given 'type' and room for 'size' bytes of
+ * data as its payload, plus Netlink padding if needed, to the tail end of
+ * 'msg', reallocating and copying its data if necessary. Returns a pointer to
+ * the first byte of data in the attribute, which is zeroed. */
+void *
+nl_msg_put_unspec_zero(struct ofpbuf *msg, uint16_t type, size_t size)
+{
+ void *data = nl_msg_put_unspec_uninit(msg, type, size);
+ memset(data, 0, size);
+ return data;
+}
+
/* Appends a Netlink attribute of the given 'type' and the 'size' bytes of
* 'data' as its payload, to the tail end of 'msg', reallocating and copying
* its data if necessary. Returns a pointer to the first byte of data in the
nl_msg_put_unspec(msg, type, &value, sizeof value);
}
+/* Appends a Netlink attribute of the given 'type' and the given odp_port_t
+ * 'value' to 'msg'. */
+void
+nl_msg_put_odp_port(struct ofpbuf *msg, uint16_t type, odp_port_t value)
+{
+ nl_msg_put_u32(msg, type, odp_to_u32(value));
+}
+
+
/* Appends a Netlink attribute of the given 'type' and the given
* null-terminated string 'value' to 'msg'. */
void
{
size_t total_size = NLA_HDRLEN + size;
struct nlattr* nla = nl_msg_push_uninit(msg, total_size);
- assert(NLA_ALIGN(total_size) <= UINT16_MAX);
+ ovs_assert(!nl_attr_oversized(size));
nla->nla_len = total_size;
nla->nla_type = type;
return nla + 1;
msg->size = 0;
return NULL;
}
+
+/* Returns true if a Netlink attribute with a payload that is 'payload_size'
+ * bytes long would be oversized, that is, if it's not possible to create an
+ * nlattr of that size because its size wouldn't fit in the 16-bit nla_len
+ * field. */
+bool
+nl_attr_oversized(size_t payload_size)
+{
+ return NL_ATTR_SIZE(payload_size) > UINT16_MAX;
+}
\f
/* Attributes. */
const void *
nl_attr_get(const struct nlattr *nla)
{
- assert(nla->nla_len >= NLA_HDRLEN);
+ ovs_assert(nla->nla_len >= NLA_HDRLEN);
return nla + 1;
}
size_t
nl_attr_get_size(const struct nlattr *nla)
{
- assert(nla->nla_len >= NLA_HDRLEN);
+ ovs_assert(nla->nla_len >= NLA_HDRLEN);
return nla->nla_len - NLA_HDRLEN;
}
const void *
nl_attr_get_unspec(const struct nlattr *nla, size_t size)
{
- assert(nla->nla_len >= NLA_HDRLEN + size);
+ ovs_assert(nla->nla_len >= NLA_HDRLEN + size);
return nla + 1;
}
return get_32aligned_be64(x);
}
+/* Returns the 32-bit odp_port_t value in 'nla''s payload.
+ *
+ * Asserts that 'nla''s payload is at least 4 bytes long. */
+odp_port_t
+nl_attr_get_odp_port(const struct nlattr *nla)
+{
+ return u32_to_odp(nl_attr_get_u32(nla));
+}
+
/* Returns the null-terminated string value in 'nla''s payload.
*
* Asserts that 'nla''s payload contains a null-terminated string. */
const char *
nl_attr_get_string(const struct nlattr *nla)
{
- assert(nla->nla_len > NLA_HDRLEN);
- assert(memchr(nl_attr_get(nla), '\0', nla->nla_len - NLA_HDRLEN) != NULL);
+ ovs_assert(nla->nla_len > NLA_HDRLEN);
+ ovs_assert(memchr(nl_attr_get(nla), '\0', nla->nla_len - NLA_HDRLEN));
return nl_attr_get(nla);
}
ofpbuf_use_const(nested, nl_attr_get(nla), nl_attr_get_size(nla));
}
-/* Default minimum and maximum payload sizes for each type of attribute. */
-static const size_t attr_len_range[][2] = {
- [0 ... N_NL_ATTR_TYPES - 1] = { 0, SIZE_MAX },
- [NL_A_U8] = { 1, 1 },
- [NL_A_U16] = { 2, 2 },
- [NL_A_U32] = { 4, 4 },
- [NL_A_U64] = { 8, 8 },
- [NL_A_STRING] = { 1, SIZE_MAX },
- [NL_A_FLAG] = { 0, SIZE_MAX },
- [NL_A_NESTED] = { 0, SIZE_MAX },
-};
+/* Default minimum payload size for each type of attribute. */
+static size_t
+min_attr_len(enum nl_attr_type type)
+{
+ switch (type) {
+ case NL_A_NO_ATTR: return 0;
+ case NL_A_UNSPEC: return 0;
+ case NL_A_U8: return 1;
+ case NL_A_U16: return 2;
+ case NL_A_U32: return 4;
+ case NL_A_U64: return 8;
+ case NL_A_STRING: return 1;
+ case NL_A_FLAG: return 0;
+ case NL_A_NESTED: return 0;
+ case N_NL_ATTR_TYPES: default: OVS_NOT_REACHED();
+ }
+}
+
+/* Default maximum payload size for each type of attribute. */
+static size_t
+max_attr_len(enum nl_attr_type type)
+{
+ switch (type) {
+ case NL_A_NO_ATTR: return SIZE_MAX;
+ case NL_A_UNSPEC: return SIZE_MAX;
+ case NL_A_U8: return 1;
+ case NL_A_U16: return 2;
+ case NL_A_U32: return 4;
+ case NL_A_U64: return 8;
+ case NL_A_STRING: return SIZE_MAX;
+ case NL_A_FLAG: return SIZE_MAX;
+ case NL_A_NESTED: return SIZE_MAX;
+ case N_NL_ATTR_TYPES: default: OVS_NOT_REACHED();
+ }
+}
bool
nl_attr_validate(const struct nlattr *nla, const struct nl_policy *policy)
/* Figure out min and max length. */
min_len = policy->min_len;
if (!min_len) {
- min_len = attr_len_range[policy->type][0];
+ min_len = min_attr_len(policy->type);
}
max_len = policy->max_len;
if (!max_len) {
- max_len = attr_len_range[policy->type][1];
+ max_len = max_attr_len(policy->type);
}
/* Verify length. */
len = nl_attr_get_size(nla);
if (len < min_len || len > max_len) {
- VLOG_DBG_RL(&rl, "attr %"PRIu16" length %zu not in "
- "allowed range %zu...%zu", type, len, min_len, max_len);
+ VLOG_DBG_RL(&rl, "attr %"PRIu16" length %"PRIuSIZE" not in "
+ "allowed range %"PRIuSIZE"...%"PRIuSIZE, type, len, min_len, max_len);
return false;
}
return false;
}
- NL_ATTR_FOR_EACH (nla, left,
- (struct nlattr *) ((char *) msg->data + nla_offset),
+ NL_ATTR_FOR_EACH (nla, left, ofpbuf_at(msg, nla_offset, 0),
msg->size - nla_offset)
{
uint16_t type = nl_attr_type(nla);
for (i = 0; i < n_attrs; i++) {
const struct nl_policy *e = &policy[i];
if (!e->optional && e->type != NL_A_NO_ATTR && !attrs[i]) {
- VLOG_DBG_RL(&rl, "required attr %zu missing", i);
+ VLOG_DBG_RL(&rl, "required attr %"PRIuSIZE" missing", i);
return false;
}
}
const struct nlattr *
nl_attr_find(const struct ofpbuf *buf, size_t hdr_len, uint16_t type)
{
- const uint8_t *start = (const uint8_t *) buf->data + hdr_len;
- return nl_attr_find__((const struct nlattr *) start, buf->size - hdr_len,
+ return nl_attr_find__(ofpbuf_at(buf, hdr_len, 0), buf->size - hdr_len,
type);
}