Investigate Solaris TCP using dtrace

mishuang

client.d
client.c
server.d
server.c
readdir.c
Makefile如下：
all:
    gcc -lnsl -lsocket -o server server.c readdir.c
    gcc -lnsl -lsocket -o client client.c
首先在一台机器上起服务器进程，假设服务器hostname是necho。
客户端执行./client /sbin necho就会将necho上/sbin目录下的文件名返回。这个例子是在网上找的，稍加改动。
client端输出如下：
# ./client.d
total length:    034
sequence number:    fd919d60
acknowledgement number:    ecc39788
12
total length:    028
sequence number:    fd919d61
acknowledgement number:    ecc3978d
10
total length:    19d
sequence number:    fd919d61
acknowledgement number:    ecc3978d
18
total length:    028
sequence number:    fd919ed6
acknowledgement number:    ecc3978d
11
total length:    028
sequence number:    fd919ed7
acknowledgement number:    ecc3978e
10
server端输入如下：
# ./server.d
total length:   034
sequence number:        ecc39787
acknowledgement number: 0000
2
total length:   028
sequence number:        ecc39788
acknowledgement number: fd919d61
10
total length:   02d
sequence number:        ecc39788
acknowledgement number: fd919d61
18
total length:   028
sequence number:        ecc3978d
acknowledgement number: fd919ed6
10
total length:   028
sequence number:        ecc3978d
acknowledgement number: fd919ed7
10
total length:   028
sequence number:        ecc3978d
acknowledgement number: fd919ed7
11
分析如下：
Three-way handshake
1. Server receives client SYN.
total length:   034
sequence number:        ecc39787(x)
acknowledgement number: 0000
2(SYN)
2. Client receives SYN+ACK from server.
total length:    034
sequence number:    fd919d60(y)
acknowledgement number:    ecc39788(x+1)
12(ACK+SYN)
3. Server receives ACK from client.
total length:   028
sequence number:        ecc39788(x+1)
acknowledgement number: fd919d61(y+1)
10(ACK)
Client sends "/sbin", five bytes to server.
total length:   02d(0x2d=40+5)
sequence number:        ecc39788(x+1)
acknowledgement number: fd919d61(y+1)
18(ACK+PSH)
total length:    028(0x28=40, the length of TCP+IP headers)
sequence number:    fd919d61(y+1)
acknowledgement number:    ecc3978d(x+1+5)
10(ACK)
Server sends 373 bytes to client
total length:    19d(0x19d=40+373)
sequence number:    fd919d61(y+1)
acknowledgement number:    ecc3978d(x+1+5)
18
total length:   028
sequence number:        ecc3978d(x+1+5)
acknowledgement number: fd919ed6(y+1+373)
10
Server closes the connection.
total length:    028
sequence number:    fd919ed6(y+1+373)
acknowledgement number:    ecc3978d(x+1+5)
11(ACK+FIN)
total length:   028
sequence number:        ecc3978d(x+1+5)
acknowledgement number: fd919ed7(y+1+373+1)
10
Client closes the connection.
total length:   028
sequence number:        ecc3978d(x+1+5)
acknowledgement number: fd919ed7(y+1+373+1)
11
total length:    028
sequence number:    fd919ed7(y+1+373+1)
acknowledgement number:    ecc3978e(x+1+5+1)
10


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