From 282093f1fe783b5d36a014d4495995cd64e2e3fb Mon Sep 17 00:00:00 2001 From: Ole Troan Date: Wed, 19 Sep 2018 12:38:51 +0200 Subject: IPIP and IPv6 fragmentation - Error where ICMPv6 error code doesn't reset VLIB_TX = -1 Leading to crash for ICMP generated on tunnelled packets - Missed setting VNET_BUFFER_F_LOCALLY_ORIGINATED, so IP in IPv6 packets never got fragmented. - Add support for fragmentation of buffer chains. - Remove support for inner fragmentation in frag code itself. Change-Id: If9a97301b7e35ca97ffa5c0fada2b9e7e7dbfb27 Signed-off-by: Ole Troan --- src/vnet/ip/icmp6.c | 23 ++- src/vnet/ip/ip4_forward.c | 2 +- src/vnet/ip/ip6_forward.c | 3 +- src/vnet/ip/ip_frag.c | 462 +++++++++++++++++++--------------------------- src/vnet/ip/ip_frag.h | 2 +- 5 files changed, 206 insertions(+), 286 deletions(-) (limited to 'src/vnet/ip') diff --git a/src/vnet/ip/icmp6.c b/src/vnet/ip/icmp6.c index 6ebdef4745e..4252ac7ad59 100644 --- a/src/vnet/ip/icmp6.c +++ b/src/vnet/ip/icmp6.c @@ -524,14 +524,24 @@ ip6_icmp_error (vlib_main_t * vm, { b = vlib_get_buffer (vm, b->next_buffer); b->current_length = 0; + // XXX: Buffer leak??? } } /* Add IP header and ICMPv6 header including a 4 byte data field */ - vlib_buffer_advance (p0, - -sizeof (ip6_header_t) - - sizeof (icmp46_header_t) - 4); + int headroom = sizeof (ip6_header_t) + sizeof (icmp46_header_t) + 4; + /* Verify that we're not falling off the edge */ + if (p0->current_data - headroom < -VLIB_BUFFER_PRE_DATA_SIZE) + { + next0 = IP6_ICMP_ERROR_NEXT_DROP; + error0 = ICMP6_ERROR_DROP; + goto error; + } + + vlib_buffer_advance (p0, -headroom); + vnet_buffer (p0)->sw_if_index[VLIB_TX] = ~0; + p0->flags |= VNET_BUFFER_F_LOCALLY_ORIGINATED; p0->current_length = p0->current_length > 1280 ? 1280 : p0->current_length; @@ -561,6 +571,7 @@ ip6_icmp_error (vlib_main_t * vm, { next0 = IP6_ICMP_ERROR_NEXT_DROP; error0 = ICMP6_ERROR_DROP; + goto error; } /* Fill icmp header fields */ @@ -573,11 +584,11 @@ ip6_icmp_error (vlib_main_t * vm, ip6_tcp_udp_icmp_compute_checksum (vm, p0, out_ip0, &bogus_length); - - /* Update error status */ if (error0 == ICMP6_ERROR_NONE) error0 = icmp6_icmp_type_to_error (icmp0->type); + + error: vlib_error_count (vm, node->node_index, error0, 1); /* Verify speculative enqueue, maybe switch current next frame */ @@ -602,7 +613,7 @@ VLIB_REGISTER_NODE (ip6_icmp_error_node) = { .n_next_nodes = IP6_ICMP_ERROR_N_NEXT, .next_nodes = { - [IP6_ICMP_ERROR_NEXT_DROP] = "ip6-drop", + [IP6_ICMP_ERROR_NEXT_DROP] = "error-drop", [IP6_ICMP_ERROR_NEXT_LOOKUP] = "ip6-lookup", }, diff --git a/src/vnet/ip/ip4_forward.c b/src/vnet/ip/ip4_forward.c index d5cf011b677..d5e2cd56e77 100644 --- a/src/vnet/ip/ip4_forward.c +++ b/src/vnet/ip/ip4_forward.c @@ -2097,7 +2097,7 @@ ip4_mtu_check (vlib_buffer_t * b, u16 packet_len, else { /* IP fragmentation */ - ip_frag_set_vnet_buffer (b, 0, adj_packet_bytes, + ip_frag_set_vnet_buffer (b, adj_packet_bytes, IP4_FRAG_NEXT_IP4_REWRITE, 0); *next = IP4_REWRITE_NEXT_FRAGMENT; } diff --git a/src/vnet/ip/ip6_forward.c b/src/vnet/ip/ip6_forward.c index 5abbba59617..e05792fe28f 100644 --- a/src/vnet/ip/ip6_forward.c +++ b/src/vnet/ip/ip6_forward.c @@ -1566,9 +1566,10 @@ ip6_mtu_check (vlib_buffer_t * b, u16 packet_bytes, if (is_locally_generated) { /* IP fragmentation */ - ip_frag_set_vnet_buffer (b, 0, adj_packet_bytes, + ip_frag_set_vnet_buffer (b, adj_packet_bytes, IP6_FRAG_NEXT_IP6_REWRITE, 0); *next = IP6_REWRITE_NEXT_FRAGMENT; + *error = IP6_ERROR_MTU_EXCEEDED; } else { diff --git a/src/vnet/ip/ip_frag.c b/src/vnet/ip/ip_frag.c index eb9bb4a5ebc..628d9d66474 100644 --- a/src/vnet/ip/ip_frag.c +++ b/src/vnet/ip/ip_frag.c @@ -27,7 +27,6 @@ typedef struct { u8 ipv6; - u16 header_offset; u16 mtu; u8 next; u16 n_fragments; @@ -39,13 +38,48 @@ format_ip_frag_trace (u8 * s, va_list * args) CLIB_UNUSED (vlib_main_t * vm) = va_arg (*args, vlib_main_t *); CLIB_UNUSED (vlib_node_t * node) = va_arg (*args, vlib_node_t *); ip_frag_trace_t *t = va_arg (*args, ip_frag_trace_t *); - s = format (s, "IPv%s offset: %u mtu: %u fragments: %u", - t->ipv6 ? "6" : "4", t->header_offset, t->mtu, t->n_fragments); + s = format (s, "IPv%s mtu: %u fragments: %u", + t->ipv6 ? "6" : "4", t->mtu, t->n_fragments); return s; } static u32 running_fragment_id; +static void +frag_set_sw_if_index (vlib_buffer_t * to, vlib_buffer_t * from) +{ + vnet_buffer (to)->sw_if_index[VLIB_RX] = + vnet_buffer (from)->sw_if_index[VLIB_RX]; + vnet_buffer (to)->sw_if_index[VLIB_TX] = + vnet_buffer (from)->sw_if_index[VLIB_TX]; + + /* Copy adj_index in case DPO based node is sending for the + * fragmentation, the packet would be sent back to the proper + * DPO next node and Index + */ + vnet_buffer (to)->ip.adj_index[VLIB_RX] = + vnet_buffer (from)->ip.adj_index[VLIB_RX]; + vnet_buffer (to)->ip.adj_index[VLIB_TX] = + vnet_buffer (from)->ip.adj_index[VLIB_TX]; +} + +static vlib_buffer_t * +frag_buffer_alloc (vlib_buffer_t * org_b, u32 * bi) +{ + vlib_main_t *vm = vlib_get_main (); + if (vlib_buffer_alloc (vm, bi, 1) != 1) + return 0; + + vlib_buffer_t *b = vlib_get_buffer (vm, *bi); + vlib_buffer_free_list_t *fl = + vlib_buffer_get_free_list (vm, VLIB_BUFFER_DEFAULT_FREE_LIST_INDEX); + vlib_buffer_init_for_free_list (b, fl); + VLIB_BUFFER_TRACE_TRAJECTORY_INIT (b); + vlib_buffer_copy_trace_flag (vm, org_b, *bi); + + return b; +} + /* * Limitation: Does follow buffer chains in the packet to fragment, * but does not generate buffer chains. I.e. a fragment is always @@ -58,23 +92,19 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, { vlib_buffer_t *from_b; ip4_header_t *ip4; - u16 mtu, len, max, rem, offset, ip_frag_id, ip_frag_offset; + u16 mtu, len, max, rem, ip_frag_id, ip_frag_offset; u8 *org_from_packet, more; from_b = vlib_get_buffer (vm, from_bi); - offset = vnet_buffer (from_b)->ip_frag.header_offset; mtu = vnet_buffer (from_b)->ip_frag.mtu; org_from_packet = vlib_buffer_get_current (from_b); - ip4 = (ip4_header_t *) vlib_buffer_get_current (from_b) + offset; + ip4 = (ip4_header_t *) vlib_buffer_get_current (from_b); rem = clib_net_to_host_u16 (ip4->length) - sizeof (ip4_header_t); - max = - (mtu - sizeof (ip4_header_t) - - vnet_buffer (from_b)->ip_frag.header_offset) & ~0x7; + max = (mtu - sizeof (ip4_header_t)) & ~0x7; if (rem > - (vlib_buffer_length_in_chain (vm, from_b) - offset - - sizeof (ip4_header_t))) + (vlib_buffer_length_in_chain (vm, from_b) - sizeof (ip4_header_t))) { *error = IP_FRAG_ERROR_MALFORMED; return; @@ -110,9 +140,9 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, u8 *from_data = (void *) (ip4 + 1); vlib_buffer_t *org_from_b = from_b; - u16 ptr = 0, fo = 0; - u16 left_in_from_buffer = - from_b->current_length - offset - sizeof (ip4_header_t); + u16 fo = 0; + u16 left_in_from_buffer = from_b->current_length - sizeof (ip4_header_t); + u16 ptr = 0; /* Do the actual fragmentation */ while (rem) @@ -122,40 +152,28 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, ip4_header_t *to_ip4; u8 *to_data; - len = (rem > (mtu - sizeof (ip4_header_t) - offset) ? max : rem); + len = (rem > (mtu - sizeof (ip4_header_t)) ? max : rem); if (len != rem) /* Last fragment does not need to divisible by 8 */ len &= ~0x7; - if (!vlib_buffer_alloc (vm, &to_bi, 1)) + if ((to_b = frag_buffer_alloc (org_from_b, &to_bi)) == 0) { *error = IP_FRAG_ERROR_MEMORY; return; } vec_add1 (*buffer, to_bi); - to_b = vlib_get_buffer (vm, to_bi); - vnet_buffer (to_b)->sw_if_index[VLIB_RX] = - vnet_buffer (org_from_b)->sw_if_index[VLIB_RX]; - vnet_buffer (to_b)->sw_if_index[VLIB_TX] = - vnet_buffer (org_from_b)->sw_if_index[VLIB_TX]; - /* Copy adj_index in case DPO based node is sending for the - * fragmentation, the packet would be sent back to the proper - * DPO next node and Index - */ - vnet_buffer (to_b)->ip.adj_index[VLIB_RX] = - vnet_buffer (org_from_b)->ip.adj_index[VLIB_RX]; - vnet_buffer (to_b)->ip.adj_index[VLIB_TX] = - vnet_buffer (org_from_b)->ip.adj_index[VLIB_TX]; - - /* Copy offset and ip4 header */ - clib_memcpy (to_b->data, org_from_packet, - offset + sizeof (ip4_header_t)); - to_ip4 = vlib_buffer_get_current (to_b) + offset; + frag_set_sw_if_index (to_b, org_from_b); + + /* Copy ip4 header */ + clib_memcpy (to_b->data, org_from_packet, sizeof (ip4_header_t)); + to_ip4 = vlib_buffer_get_current (to_b); to_data = (void *) (to_ip4 + 1); /* Spin through from buffers filling up the to buffer */ - u16 to_ptr = 0; - u16 bytes_to_copy, left_in_to_buffer = len; + u16 left_in_to_buffer = len, to_ptr = 0; while (1) { + u16 bytes_to_copy; + /* Figure out how many bytes we can safely copy */ bytes_to_copy = left_in_to_buffer <= left_in_from_buffer ? left_in_to_buffer : left_in_from_buffer; @@ -166,7 +184,7 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, if (left_in_to_buffer == 0) break; - ASSERT (left_in_from_buffer == 0); + ASSERT (left_in_from_buffer <= 0); /* Move buffer */ if (!(from_b->flags & VLIB_BUFFER_NEXT_PRESENT)) { @@ -180,7 +198,7 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, to_ptr += bytes_to_copy; } - to_b->current_length = offset + len + sizeof (ip4_header_t); + to_b->current_length = len + sizeof (ip4_header_t); to_ip4->fragment_id = ip_frag_id; to_ip4->flags_and_fragment_offset = @@ -214,21 +232,20 @@ ip4_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, } void -ip_frag_set_vnet_buffer (vlib_buffer_t * b, u16 offset, u16 mtu, - u8 next_index, u8 flags) +ip_frag_set_vnet_buffer (vlib_buffer_t * b, u16 mtu, u8 next_index, u8 flags) { - vnet_buffer (b)->ip_frag.header_offset = offset; vnet_buffer (b)->ip_frag.mtu = mtu; vnet_buffer (b)->ip_frag.next_index = next_index; vnet_buffer (b)->ip_frag.flags = flags; } -static uword -ip4_frag (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) + +static inline uword +frag_node_inline (vlib_main_t * vm, vlib_node_runtime_t * node, + vlib_frame_t * frame, u32 node_index, bool is_ip6) { u32 n_left_from, *from, next_index, *to_next, n_left_to_next; - vlib_node_runtime_t *error_node = - vlib_node_get_runtime (vm, ip4_frag_node.index); + vlib_node_runtime_t *error_node = vlib_node_get_runtime (vm, node_index); from = vlib_frame_vector_args (frame); n_left_from = frame->n_vectors; next_index = node->cached_next_index; @@ -244,58 +261,68 @@ ip4_frag (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) u32 pi0, *frag_from, frag_left; vlib_buffer_t *p0; ip_frag_error_t error0; - ip4_frag_next_t next0; + int next0; - //Note: The packet is not enqueued now. - //It is instead put in a vector where other fragments - //will be put as well. + /* + * Note: The packet is not enqueued now. It is instead put + * in a vector where other fragments will be put as well. + */ pi0 = from[0]; from += 1; n_left_from -= 1; error0 = IP_FRAG_ERROR_NONE; p0 = vlib_get_buffer (vm, pi0); - ip4_frag_do_fragment (vm, pi0, &buffer, &error0); + if (is_ip6) + ip6_frag_do_fragment (vm, pi0, &buffer, &error0); + else + ip4_frag_do_fragment (vm, pi0, &buffer, &error0); if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED)) { ip_frag_trace_t *tr = vlib_add_trace (vm, node, p0, sizeof (*tr)); - tr->header_offset = vnet_buffer (p0)->ip_frag.header_offset; tr->mtu = vnet_buffer (p0)->ip_frag.mtu; - tr->ipv6 = 0; + tr->ipv6 = is_ip6 ? 1 : 0; tr->n_fragments = vec_len (buffer); tr->next = vnet_buffer (p0)->ip_frag.next_index; } - if (error0 == IP_FRAG_ERROR_DONT_FRAGMENT_SET) + if (!is_ip6 && error0 == IP_FRAG_ERROR_DONT_FRAGMENT_SET) { icmp4_error_set_vnet_buffer (p0, ICMP4_destination_unreachable, ICMP4_destination_unreachable_fragmentation_needed_and_dont_fragment_set, vnet_buffer (p0)->ip_frag.mtu); - vlib_buffer_advance (p0, - vnet_buffer (p0)->ip_frag.header_offset); next0 = IP4_FRAG_NEXT_ICMP_ERROR; } else { - /* *INDENT-OFF* */ - next0 = (error0 == IP_FRAG_ERROR_NONE) ? vnet_buffer (p0)-> - ip_frag.next_index : IP4_FRAG_NEXT_DROP; - /* *INDENT-ON* */ + if (is_ip6) + next0 = + (error0 == + IP_FRAG_ERROR_NONE) ? vnet_buffer (p0)-> + ip_frag.next_index : IP6_FRAG_NEXT_DROP; + else + next0 = + (error0 == + IP_FRAG_ERROR_NONE) ? vnet_buffer (p0)-> + ip_frag.next_index : IP4_FRAG_NEXT_DROP; } if (error0 == IP_FRAG_ERROR_NONE) { /* Free original buffer chain */ - vlib_buffer_free_one (vm, pi0); frag_sent += vec_len (buffer); small_packets += (vec_len (buffer) == 1); + vlib_buffer_free_one (vm, pi0); /* Free original packet */ } else - vlib_error_count (vm, ip4_frag_node.index, error0, 1); + { + vlib_error_count (vm, node_index, error0, 1); + vec_add1 (buffer, pi0); /* Get rid of the original buffer */ + } - //Send fragments that were added in the frame + /* Send fragments that were added in the frame */ frag_from = buffer; frag_left = vec_len (buffer); @@ -325,262 +352,143 @@ ip4_frag (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) } vec_free (buffer); - vlib_node_increment_counter (vm, ip4_frag_node.index, + vlib_node_increment_counter (vm, node_index, IP_FRAG_ERROR_FRAGMENT_SENT, frag_sent); - vlib_node_increment_counter (vm, ip4_frag_node.index, + vlib_node_increment_counter (vm, node_index, IP_FRAG_ERROR_SMALL_PACKET, small_packets); return frame->n_vectors; } + +static uword +ip4_frag (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + return frag_node_inline (vm, node, frame, ip4_frag_node.index, + 0 /* is_ip6 */ ); +} + +static uword +ip6_frag (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) +{ + return frag_node_inline (vm, node, frame, ip6_frag_node.index, + 1 /* is_ip6 */ ); +} + +/* + * Fragments the packet given in from_bi. Fragments are returned in the buffer vector. + * Caller must ensure the original packet is freed. + */ void -ip6_frag_do_fragment (vlib_main_t * vm, u32 pi, u32 ** buffer, +ip6_frag_do_fragment (vlib_main_t * vm, u32 from_bi, u32 ** buffer, ip_frag_error_t * error) { - vlib_buffer_t *p; - ip6_header_t *ip6_hdr; - ip6_frag_hdr_t *frag_hdr; - u8 *payload, *next_header; - - p = vlib_get_buffer (vm, pi); - - //Parsing the IPv6 headers - ip6_hdr = - vlib_buffer_get_current (p) + vnet_buffer (p)->ip_frag.header_offset; - payload = (u8 *) (ip6_hdr + 1); - next_header = &ip6_hdr->protocol; - if (*next_header == IP_PROTOCOL_IP6_HOP_BY_HOP_OPTIONS) - { - next_header = payload; - payload += payload[1] * 8; - } + vlib_buffer_t *from_b; + ip6_header_t *ip6; + u16 mtu, len, max, rem, ip_frag_id; - if (*next_header == IP_PROTOCOL_IP6_DESTINATION_OPTIONS) - { - next_header = payload; - payload += payload[1] * 8; - } + from_b = vlib_get_buffer (vm, from_bi); + mtu = vnet_buffer (from_b)->ip_frag.mtu; + ip6 = (ip6_header_t *) vlib_buffer_get_current (from_b); - if (*next_header == IP_PROTOCOL_IPV6_ROUTE) - { - next_header = payload; - payload += payload[1] * 8; - } + rem = clib_net_to_host_u16 (ip6->payload_length); + max = (mtu - sizeof (ip6_header_t) - sizeof (ip6_frag_hdr_t)) & ~0x7; // TODO: Is max correct?? - if (PREDICT_FALSE - (payload >= (u8 *) vlib_buffer_get_current (p) + p->current_length)) + if (rem > + (vlib_buffer_length_in_chain (vm, from_b) - sizeof (ip6_header_t))) { - //A malicious packet could set an extension header with a too big size - //and make us modify another vlib_buffer *error = IP_FRAG_ERROR_MALFORMED; return; } - if (p->flags & VLIB_BUFFER_NEXT_PRESENT) + /* TODO: Look through header chain for fragmentation header */ + if (ip6->protocol == IP_PROTOCOL_IPV6_FRAGMENTATION) { *error = IP_FRAG_ERROR_MALFORMED; return; } - u8 has_more; - u16 initial_offset; - if (*next_header == IP_PROTOCOL_IPV6_FRAGMENTATION) - { - //The fragmentation header is already there - frag_hdr = (ip6_frag_hdr_t *) payload; - has_more = ip6_frag_hdr_more (frag_hdr); - initial_offset = ip6_frag_hdr_offset (frag_hdr); - } - else - { - //Insert a fragmentation header in the packet - u8 nh = *next_header; - *next_header = IP_PROTOCOL_IPV6_FRAGMENTATION; - vlib_buffer_advance (p, -sizeof (*frag_hdr)); - u8 *start = vlib_buffer_get_current (p); - memmove (start, start + sizeof (*frag_hdr), - payload - (start + sizeof (*frag_hdr))); - frag_hdr = (ip6_frag_hdr_t *) (payload - sizeof (*frag_hdr)); - frag_hdr->identification = ++running_fragment_id; - frag_hdr->next_hdr = nh; - frag_hdr->rsv = 0; - has_more = 0; - initial_offset = 0; - } - payload = (u8 *) (frag_hdr + 1); - - u16 headers_len = payload - (u8 *) vlib_buffer_get_current (p); - u16 max_payload = vnet_buffer (p)->ip_frag.mtu - headers_len; - u16 rem = p->current_length - headers_len; + u8 *from_data = (void *) (ip6 + 1); + vlib_buffer_t *org_from_b = from_b; + u16 fo = 0; + u16 left_in_from_buffer = from_b->current_length - sizeof (ip6_header_t); u16 ptr = 0; - if (max_payload < 8) - { - *error = IP_FRAG_ERROR_CANT_FRAGMENT_HEADER; - return; - } + ip_frag_id = ++running_fragment_id; // Fix + /* Do the actual fragmentation */ while (rem) { - u32 bi; - vlib_buffer_t *b; - u16 len = (rem > max_payload) ? (max_payload & ~0x7) : rem; - rem -= len; - - if (ptr != 0) - { - if (!vlib_buffer_alloc (vm, &bi, 1)) - { - *error = IP_FRAG_ERROR_MEMORY; - return; - } - b = vlib_get_buffer (vm, bi); - vnet_buffer (b)->sw_if_index[VLIB_RX] = - vnet_buffer (p)->sw_if_index[VLIB_RX]; - vnet_buffer (b)->sw_if_index[VLIB_TX] = - vnet_buffer (p)->sw_if_index[VLIB_TX]; - - /* Copy Adj_index in case DPO based node is sending for the fragmentation, - the packet would be sent back to the proper DPO next node and Index */ - vnet_buffer (b)->ip.adj_index[VLIB_RX] = - vnet_buffer (p)->ip.adj_index[VLIB_RX]; - vnet_buffer (b)->ip.adj_index[VLIB_TX] = - vnet_buffer (p)->ip.adj_index[VLIB_TX]; - - clib_memcpy (vlib_buffer_get_current (b), - vlib_buffer_get_current (p), headers_len); - clib_memcpy (vlib_buffer_get_current (b) + headers_len, - payload + ptr, len); - frag_hdr = - vlib_buffer_get_current (b) + headers_len - sizeof (*frag_hdr); - } - else - { - bi = pi; - b = vlib_get_buffer (vm, bi); - //frag_hdr already set here - } + u32 to_bi; + vlib_buffer_t *to_b; + ip6_header_t *to_ip6; + ip6_frag_hdr_t *to_frag_hdr; + u8 *to_data; - ip6_hdr = - vlib_buffer_get_current (b) + vnet_buffer (p)->ip_frag.header_offset; - frag_hdr->fragment_offset_and_more = - ip6_frag_hdr_offset_and_more (initial_offset + (ptr >> 3), - (rem || has_more)); - b->current_length = headers_len + len; - ip6_hdr->payload_length = - clib_host_to_net_u16 (b->current_length - - vnet_buffer (p)->ip_frag.header_offset - - sizeof (*ip6_hdr)); - - if (vnet_buffer (p)->ip_frag.flags & IP_FRAG_FLAG_IP4_HEADER) - { - //Encapsulating ipv4 header - ip4_header_t *encap_header4 = - (ip4_header_t *) vlib_buffer_get_current (b); - encap_header4->length = clib_host_to_net_u16 (b->current_length); - encap_header4->checksum = ip4_header_checksum (encap_header4); - } - else if (vnet_buffer (p)->ip_frag.flags & IP_FRAG_FLAG_IP6_HEADER) + len = + (rem > + (mtu - sizeof (ip6_header_t) - sizeof (ip6_frag_hdr_t)) ? max : rem); + if (len != rem) /* Last fragment does not need to divisible by 8 */ + len &= ~0x7; + if ((to_b = frag_buffer_alloc (org_from_b, &to_bi)) == 0) { - //Encapsulating ipv6 header - ip6_header_t *encap_header6 = - (ip6_header_t *) vlib_buffer_get_current (b); - encap_header6->payload_length = - clib_host_to_net_u16 (b->current_length - - sizeof (*encap_header6)); + *error = IP_FRAG_ERROR_MEMORY; + return; } + vec_add1 (*buffer, to_bi); + frag_set_sw_if_index (to_b, org_from_b); - vec_add1 (*buffer, bi); - - ptr += len; - } -} - -static uword -ip6_frag (vlib_main_t * vm, vlib_node_runtime_t * node, vlib_frame_t * frame) -{ - u32 n_left_from, *from, next_index, *to_next, n_left_to_next; - vlib_node_runtime_t *error_node = - vlib_node_get_runtime (vm, ip6_frag_node.index); - from = vlib_frame_vector_args (frame); - n_left_from = frame->n_vectors; - next_index = node->cached_next_index; - u32 frag_sent = 0, small_packets = 0; - u32 *buffer = 0; - - while (n_left_from > 0) - { - vlib_get_next_frame (vm, node, next_index, to_next, n_left_to_next); + /* Copy ip6 header */ + clib_memcpy (to_b->data, ip6, sizeof (ip6_header_t)); + to_ip6 = vlib_buffer_get_current (to_b); + to_frag_hdr = (ip6_frag_hdr_t *) (to_ip6 + 1); + to_data = (void *) (to_frag_hdr + 1); - while (n_left_from > 0 && n_left_to_next > 0) + /* Spin through from buffers filling up the to buffer */ + u16 left_in_to_buffer = len, to_ptr = 0; + while (1) { - u32 pi0, *frag_from, frag_left; - vlib_buffer_t *p0; - ip_frag_error_t error0; - ip6_frag_next_t next0; - - pi0 = from[0]; - from += 1; - n_left_from -= 1; - error0 = IP_FRAG_ERROR_NONE; + u16 bytes_to_copy; - p0 = vlib_get_buffer (vm, pi0); - ip6_frag_do_fragment (vm, pi0, &buffer, &error0); + /* Figure out how many bytes we can safely copy */ + bytes_to_copy = left_in_to_buffer <= left_in_from_buffer ? + left_in_to_buffer : left_in_from_buffer; + clib_memcpy (to_data + to_ptr, from_data + ptr, bytes_to_copy); + left_in_to_buffer -= bytes_to_copy; + ptr += bytes_to_copy; + left_in_from_buffer -= bytes_to_copy; + if (left_in_to_buffer == 0) + break; - if (PREDICT_FALSE (p0->flags & VLIB_BUFFER_IS_TRACED)) + ASSERT (left_in_from_buffer <= 0); + /* Move buffer */ + if (!(from_b->flags & VLIB_BUFFER_NEXT_PRESENT)) { - ip_frag_trace_t *tr = - vlib_add_trace (vm, node, p0, sizeof (*tr)); - tr->header_offset = vnet_buffer (p0)->ip_frag.header_offset; - tr->mtu = vnet_buffer (p0)->ip_frag.mtu; - tr->ipv6 = 1; - tr->n_fragments = vec_len (buffer); - tr->next = vnet_buffer (p0)->ip_frag.next_index; + *error = IP_FRAG_ERROR_MALFORMED; + return; } + from_b = vlib_get_buffer (vm, from_b->next_buffer); + from_data = (u8 *) vlib_buffer_get_current (from_b); + ptr = 0; + left_in_from_buffer = from_b->current_length; + to_ptr += bytes_to_copy; + } - /* *INDENT-OFF* */ - next0 = (error0 == IP_FRAG_ERROR_NONE) ? vnet_buffer (p0)-> - ip_frag.next_index : IP6_FRAG_NEXT_DROP; - /* *INDENT-ON* */ - - frag_sent += vec_len (buffer); - small_packets += (vec_len (buffer) == 1); - - //Send fragments that were added in the frame - frag_from = buffer; - frag_left = vec_len (buffer); - while (frag_left > 0) - { - while (frag_left > 0 && n_left_to_next > 0) - { - u32 i; - i = to_next[0] = frag_from[0]; - frag_from += 1; - frag_left -= 1; - to_next += 1; - n_left_to_next -= 1; + to_b->current_length = + len + sizeof (ip6_header_t) + sizeof (ip6_frag_hdr_t); + to_ip6->payload_length = + clib_host_to_net_u16 (len + sizeof (ip6_frag_hdr_t)); + to_ip6->protocol = IP_PROTOCOL_IPV6_FRAGMENTATION; + to_frag_hdr->fragment_offset_and_more = + ip6_frag_hdr_offset_and_more ((fo >> 3), len != rem); + to_frag_hdr->identification = ip_frag_id; + to_frag_hdr->next_hdr = ip6->protocol; + to_frag_hdr->rsv = 0; - vlib_get_buffer (vm, i)->error = error_node->errors[error0]; - vlib_validate_buffer_enqueue_x1 (vm, node, next_index, - to_next, n_left_to_next, i, - next0); - } - vlib_put_next_frame (vm, node, next_index, n_left_to_next); - vlib_get_next_frame (vm, node, next_index, to_next, - n_left_to_next); - } - vec_reset_length (buffer); - } - vlib_put_next_frame (vm, node, next_index, n_left_to_next); + rem -= len; + fo += len; } - vec_free (buffer); - vlib_node_increment_counter (vm, ip6_frag_node.index, - IP_FRAG_ERROR_FRAGMENT_SENT, frag_sent); - vlib_node_increment_counter (vm, ip6_frag_node.index, - IP_FRAG_ERROR_SMALL_PACKET, small_packets); - - return frame->n_vectors; } static char *ip4_frag_error_strings[] = { diff --git a/src/vnet/ip/ip_frag.h b/src/vnet/ip/ip_frag.h index ef5eb4c0543..06eeee82bc6 100644 --- a/src/vnet/ip/ip_frag.h +++ b/src/vnet/ip/ip_frag.h @@ -84,7 +84,7 @@ typedef enum IP_FRAG_N_ERROR, } ip_frag_error_t; -void ip_frag_set_vnet_buffer (vlib_buffer_t * b, u16 offset, u16 mtu, +void ip_frag_set_vnet_buffer (vlib_buffer_t * b, u16 mtu, u8 next_index, u8 flags); void ip4_frag_do_fragment (vlib_main_t * vm, u32 pi, u32 ** buffer, -- cgit 1.2.3-korg