[RESEND PATCH v3 7/9] net/tcp: simplify tcp header filling code

[Mikhail Kshevetskiy]

actually I know nothing about sandbox emulator


On 23.08.2024 23:47, Simon Glass wrote:
> Hi Mikhail,
>
> On Fri, 23 Aug 2024 at 09:12, Mikhail Kshevetskiy
> <mikhail.kshevetskiy at genexis.eu> wrote:
>> By the way, I'd like to know your opinion:
>>  * should I add a sample implementation of http/1.1 compatible
>> web-server to this patch series?
>>
>> This can be used as a base for other implementations like firmware
>> upgrade web-server used by some vendors.
> Do you mean using the sandbox emulator? Yes I think that would be very helpful.
>
> Regards,
> Simon
>
>
>> Mikhail Kshevetskiy
>>
>>
>> On 17.08.2024 18:58, Simon Glass wrote:
>>> Hi Mikhail,
>>>
>>> On Wed, 14 Aug 2024 at 04:32, Mikhail Kshevetskiy
>>> <mikhail.kshevetskiy at iopsys.eu> wrote:
>>>> Signed-off-by: Mikhail Kshevetskiy <mikhail.kshevetskiy at iopsys.eu>
>>>> ---
>>>>  net/tcp.c | 70 +++++++++++++++++++++++++++++--------------------------
>>>>  1 file changed, 37 insertions(+), 33 deletions(-)
>>>>
>>> Reviewed-by: Simon Glass <sjg at chromium.org>
>>>
>>> nits below
>>>
>>>> diff --git a/net/tcp.c b/net/tcp.c
>>>> index 2c34556c26d..7014d5b4f43 100644
>>>> --- a/net/tcp.c
>>>> +++ b/net/tcp.c
>>>> @@ -527,10 +527,37 @@ void net_set_syn_options(struct tcp_stream *tcp, union tcp_build_pkt *b)
>>>>         b->ip.end = TCP_O_END;
>>>>  }
>>>>
>>>> +const char *tcpflags_to_str(char tcpflags, char *buf, int size)
>>>> +{
>>>> +       int i = 0, len;
>>>> +       char *orig = buf;
>>>> +       const struct {
>>>> +               int             bit;
>>>> +               const char      *name;
>>>> +       } desc[] = {{TCP_RST, "RST"}, {TCP_SYN, "SYN"}, {TCP_PUSH, "PSH"},
>>>> +                   {TCP_FIN, "FIN"}, {TCP_ACK, "ACK"}, {0, NULL}};
>>>> +
>>>> +       *orig = '\0';
>>>> +       while (desc[i].name != NULL) {
>>> try to avoid comparing with NULL or 0
>>>
>>>> +               len = strlen(desc[i].name);
>>>> +               if (size <= len + 1)
>>>> +                       break;
>>>> +               if (buf != orig) {
>>>> +                       *buf++ = ',';
>>>> +                       size--;
>>>> +               }
>>>> +               strcpy(buf, desc[i].name);
>>>> +               buf += len;
>>>> +               size -= len;
>>>> +       }
>>>> +       return orig;
>>>> +}
>>>> +
>>>>  int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int payload_len,
>>>>                        u8 action, u32 tcp_seq_num, u32 tcp_ack_num)
>>>>  {
>>>>         union tcp_build_pkt *b = (union tcp_build_pkt *)pkt;
>>>> +       char buf[24];
>>>>         int pkt_hdr_len;
>>>>         int pkt_len;
>>>>         int tcp_len;
>>>> @@ -540,55 +567,32 @@ int tcp_set_tcp_header(struct tcp_stream *tcp, uchar *pkt, int payload_len,
>>>>          *         4 bits reserved options
>>>>          */
>>>>         b->ip.hdr.tcp_flags = action;
>>>> -       pkt_hdr_len = IP_TCP_HDR_SIZE;
>>>>         b->ip.hdr.tcp_hlen = SHIFT_TO_TCPHDRLEN_FIELD(LEN_B_TO_DW(TCP_HDR_SIZE));
>>>>
>>>>         switch (action) {
>>>>         case TCP_SYN:
>>>>                 debug_cond(DEBUG_DEV_PKT,
>>>> -                          "TCP Hdr:SYN (%pI4, %pI4, sq=%u, ak=%u)\n",
>>>> -                          &tcp->rhost, &net_ip,
>>>> -                          tcp_seq_num, tcp_ack_num);
>>>> +                          "TCP Hdr:%s (%pI4, %pI4, s=%u, a=%u)\n",
>>>> +                          tcpflags_to_str(action, buf, sizeof(buf)),
>>>> +                          &tcp->rhost, &net_ip, tcp_seq_num, tcp_ack_num);
>>>>                 net_set_syn_options(tcp, b);
>>>>                 pkt_hdr_len = IP_TCP_O_SIZE;
>>>>                 break;
>>>> -       case TCP_SYN | TCP_ACK:
>>>> -       case TCP_ACK:
>>>> -               pkt_hdr_len = IP_HDR_SIZE + net_set_ack_options(tcp, b);
>>>> -               b->ip.hdr.tcp_flags = action;
>>>> -               debug_cond(DEBUG_DEV_PKT,
>>>> -                          "TCP Hdr:ACK (%pI4, %pI4, s=%u, a=%u, A=%x)\n",
>>>> -                          &tcp->rhost, &net_ip, tcp_seq_num, tcp_ack_num,
>>>> -                          action);
>>>> -               break;
>>>> -       case TCP_FIN:
>>>> -               debug_cond(DEBUG_DEV_PKT,
>>>> -                          "TCP Hdr:FIN  (%pI4, %pI4, s=%u, a=%u)\n",
>>>> -                          &tcp->rhost, &net_ip, tcp_seq_num, tcp_ack_num);
>>>> -               payload_len = 0;
>>>> -               pkt_hdr_len = IP_TCP_HDR_SIZE;
>>>> -               break;
>>>>         case TCP_RST | TCP_ACK:
>>>>         case TCP_RST:
>>>>                 debug_cond(DEBUG_DEV_PKT,
>>>> -                          "TCP Hdr:RST  (%pI4, %pI4, s=%u, a=%u)\n",
>>>> +                          "TCP Hdr:%s (%pI4, %pI4, s=%u, a=%u)\n",
>>>> +                          tcpflags_to_str(action, buf, sizeof(buf)),
>>>>                            &tcp->rhost, &net_ip, tcp_seq_num, tcp_ack_num);
>>>> +               pkt_hdr_len = IP_TCP_HDR_SIZE;
>>>>                 break;
>>>> -       /* Notify connection closing */
>>>> -       case (TCP_FIN | TCP_ACK):
>>>> -       case (TCP_FIN | TCP_ACK | TCP_PUSH):
>>>> -               debug_cond(DEBUG_DEV_PKT,
>>>> -                          "TCP Hdr:FIN ACK PSH(%pI4, %pI4, s=%u, a=%u, A=%x)\n",
>>>> -                          &tcp->rhost, &net_ip,
>>>> -                          tcp_seq_num, tcp_ack_num, action);
>>>> -               fallthrough;
>>>>         default:
>>>>                 pkt_hdr_len = IP_HDR_SIZE + net_set_ack_options(tcp, b);
>>>> -               b->ip.hdr.tcp_flags = action | TCP_PUSH | TCP_ACK;
>>>>                 debug_cond(DEBUG_DEV_PKT,
>>>> -                          "TCP Hdr:dft  (%pI4, %pI4, s=%u, a=%u, A=%x)\n",
>>>> -                          &tcp->rhost, &net_ip,
>>>> -                          tcp_seq_num, tcp_ack_num, action);
>>>> +                          "TCP Hdr:%s (%pI4, %pI4, s=%u, a=%u)\n",
>>>> +                          tcpflags_to_str(action, buf, sizeof(buf)),
>>>> +                          &tcp->rhost, &net_ip, tcp_seq_num, tcp_ack_num);
>>>> +               break;
>>>>         }
>>>>
>>>>         pkt_len = pkt_hdr_len + payload_len;
>>>> --
>>>> 2.39.2
>>>>
>>> Regards,
>>> Simon