Thank you for the answer.

I was reading the mails on lsm, but it wasn't obvious to me, that right
now libcap-2.0 is for 64-bit capabilities which are currently only in
-mm.

I personally find the situation right now a little bit unfortunate.
During holidays - I can imagine - quite a few people like to try new
features in anticipating the 2.6 24 release.
Libcap-2.x is for 64-bit caps which is now only in 2.6.24-rc5-mm1
and libcap-1.0 which works for 2.6.24-rc5/6 is not accessible.

BTW your article got slashdotted:
http://linux.slashdot.org/article.pl?sid=07/12/22/209212


... and have a nice christmas

Chris



On Sun, 23 Dec 2007 17:24:50 -0600
[EMAIL PROTECTED] wrote:

> libcap-2.0 is for 64-bit capabilities which are currently
> only in -mm.  So switch your kernel to 2.6.24-rc5-mm1, or
> use the latest libcap-1.x.
> 
> I actually confused myself the same way two weeks ago or
> so :)
> 
> It almost seems worth it to have libcap-2.x use 32-bit file
> capabilities so long as no capabilities above 31 need to
> be set, just to avoid gratuitous headaches until 2.6.25.
> Andrew, what do you think?
> 
> -serge
> 
> Quoting Chris Friedhoff ([EMAIL PROTECTED]):
> > Hello,
> > 
> > I'm (still) updating my documentation on
> > http://www.friedhoff.org/fscaps.html.
> > 
> > I just learned, that KaiGai has taken his userspace tools offline and
> > Andrews tools are updated and are now the prefered one.
> > 
> > But I have a problem ...
> > 
> > I tried it with 2.6.24-rc5 and 2.6.24-rc6 and with libcap 2.00, 2.01,
> > 20071203 (newest in git) on an 32 bit System
> > 
> > setcap sets according to attr the capability attribute with 20 byte,
> > whereby setfcaps sets a 12 byte value.
> > getcap can read the value set by setfcaps but not by setcap.
> > Executing a by setcap "capability enabled" binary gives an "Invalid argumet"
> > error.
> > What am I missing?
> > 
> > Thanks
> > Chris
> > 
> > 
> > Commands executed on a shell:
> > -----------------------------
> > 
> > When I try to set a capability:
> > -------------------------------
> > 
> > $ sudo libcap-2.01/progs/setcap cap_net_raw=ep ping
> > $ echo $?
> > 0
> > I get:
> > $ attr -l ping
> > Attribute "capability" has a 20 byte value for ping
> > $ libcap-2.01/progs/getcap ping
> > Failed to get capabilities for file `ping' (Invalid argument)
> > ./ping localhost
> > bash: ./ping: Invalid argument
> > 
> > But when I use KaiGai's tool:
> > -----------------------------
> > 
> > $ sudo setfcaps -c cap_net_raw=p -e ping
> > $ attr -l ping
> > Attribute "capability" has a 12 byte value for ping
> > $ libcap-2.01/progs/getcap ping
> > $ ./ping localhost (works also)
> > 
> > 
> > strace outputs:
> > ---------------
> > 
> > strace output without needed privileges
> > ---------------------------------------
> > 
> > $ ls -l libcap-2.01/progs/setcap
> > -rwxr-xr-x 1 chris users 611672 Dec 23 14:02 libcap-2.01/progs/setcap
> > $
> > $ strace libcap-2.01/progs/setcap cap_net_raw=ep ping
> > execve("libcap-2.01/progs/setcap", ["libcap-2.01/progs/setcap", 
> > "cap_net_raw=ep", "ping"], [/* 55 vars */]) = 0
> > uname({sys="Linux", node="apollo", ...}) = 0
> > brk(0)                                  = 0x80ca000
> > brk(0x80cacb0)                          = 0x80cacb0
> > set_thread_area({entry_number:-1 -> 6, base_addr:0x80ca830, limit:1048575, 
> > seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, 
> > seg_not_present:0, useable:1}) = 0
> > brk(0x80ebcb0)                          = 0x80ebcb0
> > brk(0x80ec000)                          = 0x80ec000
> > capget(0x19980330, 0, NULL)             = -1 EINVAL (Invalid argument)
> > capget(0x19980330, 0, {0, 0, 0})        = 0
> > capset(0x19980330, 0, {0x80000000 /* CAP_??? */, 0, 0}) = -1 EPERM 
> > (Operation not permitted)
> > dup(2)                                  = 3
> > fcntl64(3, F_GETFL)                     = 0x2 (flags O_RDWR)
> > fstat64(3, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
> > mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 
> > 0xb7f14000
> > _llseek(3, 0, 0xbff51724, SEEK_CUR)     = -1 ESPIPE (Illegal seek)
> > write(3, "unable to set CAP_SETFCAP effect"..., 72unable to set CAP_SETFCAP 
> > effective capability: Operation not permitted
> > ) = 72
> > close(3)                                = 0
> > munmap(0xb7f14000, 4096)                = 0
> > brk(0x80eb000)                          = 0x80eb000
> > exit_group(1)                           = ?
> > Process 3718 detached
> > 
> > 
> > strace output with root owned suid bit binary
> > ---------------------------------------------
> > -rwsr-xr-x 1 root root 611672 Dec 23 14:02 libcap-2.01/progs/setcap*
> > $
> > $ strace libcap-2.01/progs/setcap cap_net_raw=ep ping
> > execve("libcap-2.01/progs/setcap", ["libcap-2.01/progs/setcap", 
> > "cap_net_raw=ep", "ping"], [/* 55 vars */]) = 0
> > uname({sys="Linux", node="apollo", ...}) = 0
> > brk(0)                                  = 0x80ca000
> > brk(0x80cacb0)                          = 0x80cacb0
> > set_thread_area({entry_number:-1 -> 6, base_addr:0x80ca830, limit:1048575, 
> > seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, 
> > seg_not_present:0, useable:1}) = 0
> > brk(0x80ebcb0)                          = 0x80ebcb0
> > brk(0x80ec000)                          = 0x80ec000
> > access("/etc/suid-debug", F_OK)         = -1 ENOENT (No such file or 
> > directory)
> > fcntl64(0, F_GETFD)                     = 0
> > fcntl64(1, F_GETFD)                     = 0
> > fcntl64(2, F_GETFD)                     = 0
> > capget(0x19980330, 0, NULL)             = -1 EINVAL (Invalid argument)
> > capget(0x19980330, 0, {0, 0, 0})        = 0
> > capset(0x19980330, 0, {0x80000000 /* CAP_??? */, 0, 0}) = -1 EPERM 
> > (Operation not permitted)
> > dup(2)                                  = 3
> > fcntl64(3, F_GETFL)                     = 0x2 (flags O_RDWR)
> > fstat64(3, {st_mode=S_IFCHR|0620, st_rdev=makedev(136, 1), ...}) = 0
> > mmap2(NULL, 4096, PROT_READ|PROT_WRITE, MAP_PRIVATE|MAP_ANONYMOUS, -1, 0) = 
> > 0xb7f99000
> > _llseek(3, 0, 0xbf9b0984, SEEK_CUR)     = -1 ESPIPE (Illegal seek)
> > write(3, "unable to set CAP_SETFCAP effect"..., 72unable to set CAP_SETFCAP 
> > effective capability: Operation not permitted
> > ) = 72
> > close(3)                                = 0
> > munmap(0xb7f99000, 4096)                = 0
> > brk(0x80eb000)                          = 0x80eb000
> > exit_group(1)                           = ?
> > Process 3724 detached
> > 
> > 
> > and the same as root
> > --------------------
> > strace libcap-2.01/progs/setcap cap_net_raw=ep ping
> > execve("libcap-2.01/progs/setcap", ["libcap-2.01/progs/setcap", 
> > "cap_net_raw=ep", "ping"], [/* 55 vars */]) = 0
> > uname({sys="Linux", node="apollo", ...}) = 0
> > brk(0)                                  = 0x80ca000
> > brk(0x80cacb0)                          = 0x80cacb0
> > set_thread_area({entry_number:-1 -> 6, base_addr:0x80ca830, limit:1048575, 
> > seg_32bit:1, contents:0, read_exec_only:0, limit_in_pages:1, 
> > seg_not_present:0, useable:1}) = 0
> > brk(0x80ebcb0)                          = 0x80ebcb0
> > brk(0x80ec000)                          = 0x80ec000
> > capget(0x19980330, 0, NULL)             = -1 EINVAL (Invalid argument)
> > capget(0x19980330, 0, 
> > {CAP_CHOWN|CAP_DAC_OVERRIDE|CAP_DAC_READ_SEARCH|CAP_FOWNER|CAP_FSETID|CAP_KILL|CAP_SETGID|CAP_SETUID|CAP_SETPCAP|CAP_LINUX_IMMUTABLE|CAP_NET_BIND_SERVICE|CAP_NET_BROADCAST|CAP_NET_ADMIN|CAP_NET_RAW|CAP_IPC_LOCK|CAP_IPC_OWNER|CAP_SYS_MODULE|CAP_SYS_RAWIO|CAP_SYS_CHROOT|CAP_SYS_PTRACE|CAP_SYS_PACCT|CAP_SYS_ADMIN|CAP_SYS_BOOT|CAP_SYS_NICE|CAP_SYS_RESOURCE|CAP_SYS_TIME|CAP_SYS_TTY_CONFIG|0xf8000000,
> >  
> > CAP_CHOWN|CAP_DAC_OVERRIDE|CAP_DAC_READ_SEARCH|CAP_FOWNER|CAP_FSETID|CAP_KILL|CAP_SETGID|CAP_SETUID|CAP_SETPCAP|CAP_LINUX_IMMUTABLE|CAP_NET_BIND_SERVICE|CAP_NET_BROADCAST|CAP_NET_ADMIN|CAP_NET_RAW|CAP_IPC_LOCK|CAP_IPC_OWNER|CAP_SYS_MODULE|CAP_SYS_RAWIO|CAP_SYS_CHROOT|CAP_SYS_PTRACE|CAP_SYS_PACCT|CAP_SYS_ADMIN|CAP_SYS_BOOT|CAP_SYS_NICE|CAP_SYS_RESOURCE|CAP_SYS_TIME|CAP_SYS_TTY_CONFIG|0xf8000000,
> >  0}) = 0
> > capset(0x19980330, 0, 
> > {CAP_CHOWN|CAP_DAC_OVERRIDE|CAP_DAC_READ_SEARCH|CAP_FOWNER|CAP_FSETID|CAP_KILL|CAP_SETGID|CAP_SETUID|CAP_SETPCAP|CAP_LINUX_IMMUTABLE|CAP_NET_BIND_SERVICE|CAP_NET_BROADCAST|CAP_NET_ADMIN|CAP_NET_RAW|CAP_IPC_LOCK|CAP_IPC_OWNER|CAP_SYS_MODULE|CAP_SYS_RAWIO|CAP_SYS_CHROOT|CAP_SYS_PTRACE|CAP_SYS_PACCT|CAP_SYS_ADMIN|CAP_SYS_BOOT|CAP_SYS_NICE|CAP_SYS_RESOURCE|CAP_SYS_TIME|CAP_SYS_TTY_CONFIG|0xf8000000,
> >  
> > CAP_CHOWN|CAP_DAC_OVERRIDE|CAP_DAC_READ_SEARCH|CAP_FOWNER|CAP_FSETID|CAP_KILL|CAP_SETGID|CAP_SETUID|CAP_SETPCAP|CAP_LINUX_IMMUTABLE|CAP_NET_BIND_SERVICE|CAP_NET_BROADCAST|CAP_NET_ADMIN|CAP_NET_RAW|CAP_IPC_LOCK|CAP_IPC_OWNER|CAP_SYS_MODULE|CAP_SYS_RAWIO|CAP_SYS_CHROOT|CAP_SYS_PTRACE|CAP_SYS_PACCT|CAP_SYS_ADMIN|CAP_SYS_BOOT|CAP_SYS_NICE|CAP_SYS_RESOURCE|CAP_SYS_TIME|CAP_SYS_TTY_CONFIG|0xf8000000,
> >  0}) = 0
> > capget(0x19980330, 0, NULL)             = -1 EINVAL (Invalid argument)
> > setxattr("ping", "security.capability", "\x01\x00\x00\x01\x00 
> > \x00\x00\x00\x00\x00\x00\x00\x00\x00\x00\x1aW\xe4\xbf", 20, 0) = 0
> > exit_group(0)                           = ?
> > Process 3727 detached
> > 
> > 
> > 
> > 
> > 
> > --------------------
> > Chris Friedhoff
> > [EMAIL PROTECTED]
> > -
> > To unsubscribe from this list: send the line "unsubscribe 
> > linux-security-module" in
> > the body of a message to [EMAIL PROTECTED]
> > More majordomo info at  http://vger.kernel.org/majordomo-info.html


--------------------
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