On Sun, Oct 28, 2018 at 11:41:14AM +0100, Bernhard Übelacker wrote: > Now it takes some time until that line "random: crng init done" > appears in dmesg. > With logging in in the qemu window this line appears just after a > few seconds, when just trying via ssh it takes much longer. > > > I tried to find out where it blocks exactly and came to that location: > > #0 0x00007fb515b1803a in getentropy (buffer=0x56285633d440, > length=length@entry=32) at ../sysdeps/unix/sysv/linux/getentropy.c:45 > #1 0x00007fb5161e3603 in syscall_random (buflen=32, buf=<optimized out>) at > ../crypto/rand/rand_unix.c:277 > #2 rand_pool_acquire_entropy (pool=pool@entry=0x5628563394e0) at > ../crypto/rand/rand_unix.c:469 > #3 0x00007fb5161e2d8d in rand_drbg_get_entropy (drbg=0x562856339e80, > pout=0x7ffd1c2bce60, entropy=<optimized out>, min_len=<optimized out>, > max_len=<optimized out>, prediction_resistance=0) at ../crypt$ > #4 0x00007fb5161e11b2 in RAND_DRBG_instantiate > (drbg=drbg@entry=0x562856339e80, pers=pers@entry=0x7fb516289d20 > <ossl_pers_string> "OpenSSL NIST SP 800-90A DRBG", perslen=perslen@entry=28) > at ../crypto/$ > #5 0x00007fb5161e21a8 in drbg_setup (parent=parent@entry=0x0) at > ../crypto/rand/drbg_lib.c:870 > #6 0x00007fb5161e222f in do_rand_drbg_init () at > ../crypto/rand/drbg_lib.c:899 > #7 do_rand_drbg_init_ossl_ () at ../crypto/rand/drbg_lib.c:884 > #8 0x00007fb5150c9827 in __pthread_once_slow (once_control=0x7fb5163118f8 > <rand_drbg_init>, init_routine=0x7fb5161e21d0 <do_rand_drbg_init_ossl_>) at > pthread_once.c:116 > #9 0x00007fb5150c98e5 in __GI___pthread_once > (once_control=once_control@entry=0x7fb5163118f8 <rand_drbg_init>, > init_routine=init_routine@entry=0x7fb5161e21d0 <do_rand_drbg_init_ossl_>) at > pthread_once.$ > #10 0x00007fb516221329 in CRYPTO_THREAD_run_once > (once=once@entry=0x7fb5163118f8 <rand_drbg_init>, > init=init@entry=0x7fb5161e21d0 <do_rand_drbg_init_ossl_>) at > ../crypto/threads_pthread.c:113 > #11 0x00007fb5161e2327 in RAND_DRBG_get0_master () at > ../crypto/rand/drbg_lib.c:1010 > #12 0x00007fb5161e235d in drbg_status () at ../crypto/rand/drbg_lib.c:992 > #13 0x00005628556a253f in seed_rng () at ../../entropy.c:238 > #14 0x000056285564b13c in main (ac=2, av=0x56285631b970) at ../../sshd.c:1696 > > Most of the stack is inside /usr/lib/x86_64-linux-gnu/libcrypto.so.1.1 > e.g libssl1.1 that got also a new upload at that time.
Thanks for the investigation. (Note also that the OpenSSH version in question is the one that switched from OpenSSL 1.0 to 1.1, which was a big change.) There were some significant changes in this area in OpenSSL 1.1.1. Would it be possible to try running OpenSSH with OpenSSL 1.1.0h to see if that makes a difference? Unfortunately this is a little complicated as it will require doing a local build of the Debian OpenSSH source package in order to reduce the dependency; let me know if you need help with setting this up. -- Colin Watson [[email protected]]
