What is my sftp server doing?

Well, I'm not familiar with DTrace, but sometimes want to find, what some application is doing. In this case I wanted to monitor my sftp server. Luckily, most illumos distributions provide dtrace patch (coming from Oracle Solaris) to find this out. Unluckily, I haven't found any documentation on it, just source code. After reading Translators chapter of DTrace Guide and looking at /usr/lib/dtrace/sftp.d I've come to this:

dtrace -n 'sftp*:::transfer-done { printf ("%d: %s %s %s %d", pid, xlate <sftpinfo_t *>((sftpproto_t*)arg0)->sfi_pathname, xlate <sftpinfo_t *>((sftpproto_t*)arg0)->sfi_user, xlate <sftpinfo_t *>((sftpproto_t*)arg0)->sfi_operation, xlate <sftpinfo_t *>((sftpproto_t*)arg0)->sfi_nbytes  ); }'

dtrace: description 'sftp*:::transfer-done ' matched 8 probes
CPU     ID                    FUNCTION:NAME
  1  80412      process_read:transfer-done 7409: /export/home/user/1.pp user read 1808
  1  80412      process_read:transfer-done 7409: /export/home/user/1.pp user read 0
  1  80411     process_write:transfer-done 7409: /export/home/user/1.pp user write 1808
  1  80412      process_read:transfer-done 7409: /export/home/user/dtrace/poll.d user read 53
  1  80412      process_read:transfer-done 7409: /export/home/user/dtrace/poll.d user read 53

Seems rather interesting to me.

DTrace: it's really cool to have it working in FreeBSD

I've just managed to enable DTrace in FreeBSD and was playing a bit with it.
I've added necessary for i386 options to my kernel config:

options KDTRACE_HOOKS
options DDB_CTF

then run:

make kernel WITH_CTF=1 KERNCONF=MyKern

and received nothing good. The only working thing was dtrace -l. Everything other complained on uid_t in psinfo.d.

ctfdump showed a lot of stuff in kernel, but there was no uid_t. So, after adding the following line to my kernel config:

makeoptions DEBUG=-g

I got working dtrace!

So, now I can launch something like this...

# dtrace -qn 'syscall::open:entry { printf ("%d %s %s\n",pid,execname,copyinstr(arg0)) ; }'
1297 sh /lib/libncurses.so.8
1297 sh /lib/libc.so.7
1297 id /etc/libmap.conf
1297 id /var/run/ld-elf.so.hints
1297 id /usr/lib/libbsm.so.3
1297 id /lib/libc.so.7
1296 make /usr/ports/Mk/bsd.licenses.mk
1296 make /usr/ports/Mk/bsd.sites.mk
1298 sh /etc/libmap.conf
1298 sh /var/run/ld-elf.so.hints
1298 sh /lib/libedit.so.7
1298 sh /lib/libncurses.so.8
1298 sh /lib/libc.so.7
1298 sysctl /etc/libmap.conf
1298 sysctl /var/run/ld-elf.so.hints
1298 sysctl /lib/libc.so.7
1296 make .depend
1299 sh /etc/libmap.conf
1299 sh /var/run/ld-elf.so.hints
1299 sh /lib/libedit.so.7
1299 sh /lib/libncurses.so.8
1299 sh /lib/libc.so.7
1299 rm /etc/libmap.conf
1299 rm /var/run/ld-elf.so.hints
1299 rm /lib/libc.so.7
1299 rm .
1299 rm /usr/ports/textproc/libxml2/work
1299 rm libxml2-2.7.7