buffer: Abort if the canary is not intact in ssh_buffer_unpack()
buffer: Abort if the canary is not intact in ssh_buffer_unpack()

Signed-off-by: Andreas Schneider <5be00ddc76278cf6077f5047ca3384a88460c671@cryptomilk.org>
Reviewed-by: Aris Adamantiadis <78e305742ac743ecf22d8139502576ac8709e0ad@0xbadc0de.be>

kedazo/libssh,wangshawn/libssh,kedazo/libssh,taikoo/libssh,mwgoldsmith/ssh,Distrotech/libssh,DouglasHeriot/libssh,sebadoom/libssh,nviennot/libssh,nviennot/libssh,taikoo/libssh,sebadoom/libssh,nviennot/libssh,Distrotech/libssh,sebadoom/libssh,pouete/libssh,kedazo/libssh,Distrotech/libssh,mwgoldsmith/libssh,wangshawn/libssh,taikoo/libssh,pouete/libssh,wangshawn/libssh,DouglasHeriot/libssh,mwgoldsmith/libssh,taikoo/libssh,wangshawn/libssh,mwgoldsmith/libssh,nviennot/libssh,sebadoom/libssh,DouglasHeriot/libssh,mwgoldsmith/ssh,Distrotech/libssh,mwgoldsmith/libssh,DouglasHeriot/libssh,pouete/libssh,mwgoldsmith/ssh,kedazo/libssh,mwgoldsmith/ssh,pouete/libssh