| Message ID | 1406737212-23351-5-git-send-email-zoltan.kiss@citrix.com |
|---|---|
| State | Changes Requested, archived |
| Delegated to: | David Miller |
| Headers | show |
From: Zoltan Kiss <zoltan.kiss@citrix.com> Date: Wed, 30 Jul 2014 17:20:12 +0100 > This is a prototype patch to enable sending IPv4 TCP packets with pktgen. The > original motivation is to test TCP GSO with xen-netback/netfront, but I'm not > sure about how the checksum should be set up, and also someone should verify the > GSO settings I'm using. > > Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> > Cc: "David S. Miller" <davem@davemloft.net> > Cc: Thomas Graf <tgraf@suug.ch> > Cc: Joe Perches <joe@perches.com> > Cc: netdev@vger.kernel.org > Cc: linux-kernel@vger.kernel.org > Cc: xen-devel@lists.xenproject.org > --- > v3: > - mention explicitly that this for IPv4 > - memset the TCP header and set up doff > - rework of checksum handling and GSO setting in fill_packet_ipv4 > - bail out in pktgen_xmit if the device won't be able to handle GSO > > diff --git a/net/core/pktgen.c b/net/core/pktgen.c > index 0d0aaac..9d93bda 100644 > --- a/net/core/pktgen.c > +++ b/net/core/pktgen.c > @@ -162,6 +162,7 @@ > #include <net/checksum.h> > #include <net/ipv6.h> > #include <net/udp.h> > +#include <net/tcp.h> > #include <net/ip6_checksum.h> > #include <net/addrconf.h> > #ifdef CONFIG_XFRM > @@ -203,6 +204,7 @@ > #define F_NODE (1<<15) /* Node memory alloc*/ > #define F_UDPCSUM (1<<16) /* Include UDP checksum */ > #define F_PATTERN (1<<17) /* Fill the payload with a pattern */ > +#define F_TCP (1<<18) /* Send TCP packet instead of UDP */ > > /* Thread control flag bits */ > #define T_STOP (1<<0) /* Stop run */ > @@ -664,6 +666,9 @@ static int pktgen_if_show(struct seq_file *seq, void *v) > if (pkt_dev->flags & F_PATTERN) > seq_puts(seq, "PATTERN "); > > + if (pkt_dev->flags & F_TCP) > + seq_puts(seq, "TCP "); > + > if (pkt_dev->flags & F_MPLS_RND) > seq_puts(seq, "MPLS_RND "); > > @@ -1342,6 +1347,12 @@ static ssize_t pktgen_if_write(struct file *file, > else if (strcmp(f, "!PATTERN") == 0) > pkt_dev->flags &= ~F_PATTERN; > > + else if (strcmp(f, "TCP") == 0) > + pkt_dev->flags |= F_TCP; > + > + else if (strcmp(f, "!TCP") == 0) > + pkt_dev->flags &= ~F_TCP; > + > else { > sprintf(pg_result, > "Flag -:%s:- unknown\nAvailable flags, (prepend ! to un-set flag):\n%s", > @@ -2955,7 +2966,8 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, > { > struct sk_buff *skb = NULL; > __u8 *eth; > - struct udphdr *udph; > + struct udphdr *udph = NULL; > + struct tcphdr *tcph; > int datalen, iplen; > struct iphdr *iph; > __be16 protocol = htons(ETH_P_IP); > @@ -3017,29 +3029,40 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, > iph = (struct iphdr *) skb_put(skb, sizeof(struct iphdr)); > > skb_set_transport_header(skb, skb->len); > - udph = (struct udphdr *) skb_put(skb, sizeof(struct udphdr)); > + > + if (pkt_dev->flags & F_TCP) { > + datalen = pkt_dev->cur_pkt_size - ETH_HLEN - 20 - > + sizeof(struct tcphdr) - pkt_dev->pkt_overhead; > + tcph = (struct tcphdr *)skb_put(skb, sizeof(struct tcphdr)); > + memset(tcph, 0, sizeof(*tcph)); > + tcph->source = htons(pkt_dev->cur_udp_src); > + tcph->dest = htons(pkt_dev->cur_udp_dst); > + tcph->doff = sizeof(struct tcphdr) >> 2; > + } else { > + datalen = pkt_dev->cur_pkt_size - ETH_HLEN - 20 - > + sizeof(struct udphdr) - pkt_dev->pkt_overhead; > + udph = (struct udphdr *)skb_put(skb, sizeof(struct udphdr)); > + udph->source = htons(pkt_dev->cur_udp_src); > + udph->dest = htons(pkt_dev->cur_udp_dst); > + udph->len = htons(datalen + sizeof(struct udphdr)); > + udph->check = 0; > + } > + As more protocols (SCTP, etc.) get supported, this is going to become completely unmanageable. Please use callbacks or something like that so this function doesn't turn into even more spaghetti. > + } else if (pkt_dev->flags & F_TCP) { > + struct inet_sock inet; > + > + inet.inet_saddr = iph->saddr; > + inet.inet_daddr = iph->daddr; > + skb->ip_summed = CHECKSUM_NONE; > + tcp_v4_send_check((struct sock *)&inet, skb); Please don't do things like this. Making fake sockets on the stack, don't do it. Do other non-socket contexts compute TCP checksums this way? Check netfilter or similar, see what they do. Worst case export __tcp_v4_send_check() or just duplicate it's contents in the tcp case here. -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
On 01/08/14 05:32, David Miller wrote: > From: Zoltan Kiss <zoltan.kiss@citrix.com> >> @@ -3017,29 +3029,40 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, >> iph = (struct iphdr *) skb_put(skb, sizeof(struct iphdr)); >> >> skb_set_transport_header(skb, skb->len); >> - udph = (struct udphdr *) skb_put(skb, sizeof(struct udphdr)); >> + >> + if (pkt_dev->flags & F_TCP) { >> + datalen = pkt_dev->cur_pkt_size - ETH_HLEN - 20 - >> + sizeof(struct tcphdr) - pkt_dev->pkt_overhead; >> + tcph = (struct tcphdr *)skb_put(skb, sizeof(struct tcphdr)); >> + memset(tcph, 0, sizeof(*tcph)); >> + tcph->source = htons(pkt_dev->cur_udp_src); >> + tcph->dest = htons(pkt_dev->cur_udp_dst); >> + tcph->doff = sizeof(struct tcphdr) >> 2; >> + } else { >> + datalen = pkt_dev->cur_pkt_size - ETH_HLEN - 20 - >> + sizeof(struct udphdr) - pkt_dev->pkt_overhead; >> + udph = (struct udphdr *)skb_put(skb, sizeof(struct udphdr)); >> + udph->source = htons(pkt_dev->cur_udp_src); >> + udph->dest = htons(pkt_dev->cur_udp_dst); >> + udph->len = htons(datalen + sizeof(struct udphdr)); >> + udph->check = 0; >> + } >> + > > As more protocols (SCTP, etc.) get supported, this is going to become > completely unmanageable. Please use callbacks or something like that > so this function doesn't turn into even more spaghetti. OK > >> + } else if (pkt_dev->flags & F_TCP) { >> + struct inet_sock inet; >> + >> + inet.inet_saddr = iph->saddr; >> + inet.inet_daddr = iph->daddr; >> + skb->ip_summed = CHECKSUM_NONE; >> + tcp_v4_send_check((struct sock *)&inet, skb); > > Please don't do things like this. Making fake sockets on the stack, don't > do it. > > Do other non-socket contexts compute TCP checksums this way? Check > netfilter or similar, see what they do. > > Worst case export __tcp_v4_send_check() or just duplicate it's contents > in the tcp case here. Indeed, it was a quick and dirty solution. I'll duplicate the relevant bits __tcp_v4_send_check -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html
diff --git a/net/core/pktgen.c b/net/core/pktgen.c index 0d0aaac..9d93bda 100644 --- a/net/core/pktgen.c +++ b/net/core/pktgen.c @@ -162,6 +162,7 @@ #include <net/checksum.h> #include <net/ipv6.h> #include <net/udp.h> +#include <net/tcp.h> #include <net/ip6_checksum.h> #include <net/addrconf.h> #ifdef CONFIG_XFRM @@ -203,6 +204,7 @@ #define F_NODE (1<<15) /* Node memory alloc*/ #define F_UDPCSUM (1<<16) /* Include UDP checksum */ #define F_PATTERN (1<<17) /* Fill the payload with a pattern */ +#define F_TCP (1<<18) /* Send TCP packet instead of UDP */ /* Thread control flag bits */ #define T_STOP (1<<0) /* Stop run */ @@ -664,6 +666,9 @@ static int pktgen_if_show(struct seq_file *seq, void *v) if (pkt_dev->flags & F_PATTERN) seq_puts(seq, "PATTERN "); + if (pkt_dev->flags & F_TCP) + seq_puts(seq, "TCP "); + if (pkt_dev->flags & F_MPLS_RND) seq_puts(seq, "MPLS_RND "); @@ -1342,6 +1347,12 @@ static ssize_t pktgen_if_write(struct file *file, else if (strcmp(f, "!PATTERN") == 0) pkt_dev->flags &= ~F_PATTERN; + else if (strcmp(f, "TCP") == 0) + pkt_dev->flags |= F_TCP; + + else if (strcmp(f, "!TCP") == 0) + pkt_dev->flags &= ~F_TCP; + else { sprintf(pg_result, "Flag -:%s:- unknown\nAvailable flags, (prepend ! to un-set flag):\n%s", @@ -2955,7 +2966,8 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, { struct sk_buff *skb = NULL; __u8 *eth; - struct udphdr *udph; + struct udphdr *udph = NULL; + struct tcphdr *tcph; int datalen, iplen; struct iphdr *iph; __be16 protocol = htons(ETH_P_IP); @@ -3017,29 +3029,40 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, iph = (struct iphdr *) skb_put(skb, sizeof(struct iphdr)); skb_set_transport_header(skb, skb->len); - udph = (struct udphdr *) skb_put(skb, sizeof(struct udphdr)); + + if (pkt_dev->flags & F_TCP) { + datalen = pkt_dev->cur_pkt_size - ETH_HLEN - 20 - + sizeof(struct tcphdr) - pkt_dev->pkt_overhead; + tcph = (struct tcphdr *)skb_put(skb, sizeof(struct tcphdr)); + memset(tcph, 0, sizeof(*tcph)); + tcph->source = htons(pkt_dev->cur_udp_src); + tcph->dest = htons(pkt_dev->cur_udp_dst); + tcph->doff = sizeof(struct tcphdr) >> 2; + } else { + datalen = pkt_dev->cur_pkt_size - ETH_HLEN - 20 - + sizeof(struct udphdr) - pkt_dev->pkt_overhead; + udph = (struct udphdr *)skb_put(skb, sizeof(struct udphdr)); + udph->source = htons(pkt_dev->cur_udp_src); + udph->dest = htons(pkt_dev->cur_udp_dst); + udph->len = htons(datalen + sizeof(struct udphdr)); + udph->check = 0; + } + skb_set_queue_mapping(skb, queue_map); skb->priority = pkt_dev->skb_priority; memcpy(eth, pkt_dev->hh, 12); *(__be16 *) & eth[12] = protocol; - /* Eth + IPh + UDPh + mpls */ - datalen = pkt_dev->cur_pkt_size - 14 - 20 - 8 - - pkt_dev->pkt_overhead; if (datalen < 0 || datalen < sizeof(struct pktgen_hdr)) datalen = sizeof(struct pktgen_hdr); - udph->source = htons(pkt_dev->cur_udp_src); - udph->dest = htons(pkt_dev->cur_udp_dst); - udph->len = htons(datalen + 8); /* DATA + udphdr */ - udph->check = 0; iph->ihl = 5; iph->version = 4; iph->ttl = 32; iph->tos = pkt_dev->tos; - iph->protocol = IPPROTO_UDP; /* UDP */ + iph->protocol = pkt_dev->flags & F_TCP ? IPPROTO_TCP : IPPROTO_UDP; iph->saddr = pkt_dev->cur_saddr; iph->daddr = pkt_dev->cur_daddr; iph->id = htons(pkt_dev->ip_id); @@ -3055,9 +3078,14 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, if (!(pkt_dev->flags & F_UDPCSUM)) { skb->ip_summed = CHECKSUM_NONE; } else if (odev->features & NETIF_F_V4_CSUM) { - skb->ip_summed = CHECKSUM_PARTIAL; - skb->csum = 0; - udp4_hwcsum(skb, udph->source, udph->dest); + skb_checksum_setup(skb, true); + } else if (pkt_dev->flags & F_TCP) { + struct inet_sock inet; + + inet.inet_saddr = iph->saddr; + inet.inet_daddr = iph->daddr; + skb->ip_summed = CHECKSUM_NONE; + tcp_v4_send_check((struct sock *)&inet, skb); } else { __wsum csum = udp_csum(skb); @@ -3072,6 +3100,20 @@ static struct sk_buff *fill_packet_ipv4(struct net_device *odev, pktgen_finalize_skb(pkt_dev, skb, datalen); + if (odev->mtu < skb->len) { + int hdrlen = skb_transport_header(skb) - skb_mac_header(skb); + + if (pkt_dev->flags & F_TCP) { + skb_shinfo(skb)->gso_type = SKB_GSO_TCPV4; + hdrlen += tcp_hdrlen(skb); + } else { + skb_shinfo(skb)->gso_type = SKB_GSO_UDP; + hdrlen += sizeof(struct udphdr); + } + skb_shinfo(skb)->gso_size = odev->mtu - hdrlen; + skb_shinfo(skb)->gso_segs = DIV_ROUND_UP(skb->len - hdrlen, skb_shinfo(skb)->gso_size); + } + #ifdef CONFIG_XFRM if (!process_ipsec(pkt_dev, skb, protocol)) return NULL; @@ -3559,6 +3601,14 @@ static void pktgen_xmit(struct pktgen_dev *pkt_dev) pkt_dev->last_pkt_size = pkt_dev->skb->len; pkt_dev->allocated_skbs++; pkt_dev->clone_count = 0; /* reset counter */ + + if (netif_needs_gso(pkt_dev->skb, netif_skb_features(pkt_dev->skb))) { + pr_err("Device don't have necessary GSO features! netif_skb_features: %llX summed %u\n", + netif_skb_features(pkt_dev->skb), + pkt_dev->skb->ip_summed); + pkt_dev->sofar++; + goto out; + } } if (pkt_dev->delay && pkt_dev->last_ok) @@ -3608,7 +3658,7 @@ unlock: HARD_TX_UNLOCK(odev, txq); local_bh_enable(); - +out: /* If pkt_dev->count is zero, then run forever */ if ((pkt_dev->count != 0) && (pkt_dev->sofar >= pkt_dev->count)) { pktgen_wait_for_skb(pkt_dev);
This is a prototype patch to enable sending IPv4 TCP packets with pktgen. The original motivation is to test TCP GSO with xen-netback/netfront, but I'm not sure about how the checksum should be set up, and also someone should verify the GSO settings I'm using. Signed-off-by: Zoltan Kiss <zoltan.kiss@citrix.com> Cc: "David S. Miller" <davem@davemloft.net> Cc: Thomas Graf <tgraf@suug.ch> Cc: Joe Perches <joe@perches.com> Cc: netdev@vger.kernel.org Cc: linux-kernel@vger.kernel.org Cc: xen-devel@lists.xenproject.org --- v3: - mention explicitly that this for IPv4 - memset the TCP header and set up doff - rework of checksum handling and GSO setting in fill_packet_ipv4 - bail out in pktgen_xmit if the device won't be able to handle GSO -- To unsubscribe from this list: send the line "unsubscribe netdev" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html