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> -----Original Message-----
> From: [email protected] [mailto:rsyslog-
> [email protected]] On Behalf Of Dražen Kacar
> Sent: Thursday, December 02, 2010 1:48 PM
> To: [email protected]
> Subject: [rsyslog] Can't use PrivDrop with TCP listener
> 
> With rsyslog 5.6.2 I tried to use UDP and TCP listeners on port 514 in
> combination with privilege drop. Config file contains:
> 
> $PrivDropToUser bulb
> $PrivDropToGroup bulb
> 
> $Ruleset indata
> $RulesetCreateMainQueue on
> 
> $InputTCPServerBindRuleset indata
> $InputTCPServerRun 514
> $InputUDPServerBindRuleset indata
> $UDPServerRun 514
> 
> I get this error:
> 
> rsyslogd: Could not create tcp listener, ignoring port 514. [try
> http://www.rsyslog.com/e/2077 ]
> 
> strace shows:
> 
> 28240 socket(PF_INET6, SOCK_DGRAM, IPPROTO_UDP) = 4
> 28240 setsockopt(4, SOL_IPV6, IPV6_V6ONLY, [1], 4) = 0
> 28240 setsockopt(4, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
> 28240 uname({sys="Linux", node="ssm2.nat.myrio.net", ...}) = 0
> 28240 fcntl(4, F_GETFL)                 = 0x2 (flags O_RDWR)
> 28240 fcntl(4, F_SETFL, O_RDWR|O_NONBLOCK) = 0
> 28240 bind(4, {sa_family=AF_INET6, sin6_port=htons(514),
> inet_pton(AF_INET6, "::", &sin6_addr), sin6_flowinfo=0,
> sin6_scope_id=0}, 28) = 0
> 
> That was IPv6 UDP socket.
> 
> 28240 socket(PF_INET, SOCK_DGRAM, IPPROTO_UDP) = 5
> 28240 setsockopt(5, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
> 28240 fcntl(5, F_GETFL)                 = 0x2 (flags O_RDWR)
> 28240 fcntl(5, F_SETFL, O_RDWR|O_NONBLOCK) = 0
> 28240 bind(5, {sa_family=AF_INET, sin_port=htons(514),
> sin_addr=inet_addr("0.0.0.0")}, 16) = 0
> 
> That was IPv4 UDP socket.
> 
> 28241 setuid(1004)                      = 0
> 28241 futex(0x40bded1c, FUTEX_WAKE_PRIVATE, 1) = 0
> 28241 futex(0x7fffc9f38600, FUTEX_WAKE_PRIVATE, 1 <unfinished ...>
> 28240 <... futex resumed> )             = 0
> 28240 setuid(1004)                      = 0
> 
> That was privilege drop.
> 
> 28243 socket(PF_INET6, SOCK_STREAM, IPPROTO_TCP) = 9
> 28243 setsockopt(9, SOL_IPV6, IPV6_V6ONLY, [1], 4) = 0
> 28243 setsockopt(9, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
> 28243 fcntl(9, F_GETFL)                 = 0x2 (flags O_RDWR)
> 28243 fcntl(9, F_SETFL, O_RDWR|O_NONBLOCK) = 0
> 28243 bind(9, {sa_family=AF_INET6, sin6_port=htons(514),
> inet_pton(AF_INET6, "::", &sin6_addr), sin6_flowinfo=0,
> sin6_scope_id=0}, 28) = -1 EACCES (Permission denied)
> 28243 close(9)                          = 0
> 28243 socket(PF_INET, SOCK_STREAM, IPPROTO_TCP) = 9
> 28243 setsockopt(9, SOL_SOCKET, SO_REUSEADDR, [1], 4) = 0
> 28243 fcntl(9, F_GETFL)                 = 0x2 (flags O_RDWR)
> 28243 fcntl(9, F_SETFL, O_RDWR|O_NONBLOCK) = 0
> 28243 bind(9, {sa_family=AF_INET, sin_port=htons(514),
> sin_addr=inet_addr("0.0.0.0")}, 16) = -1 EACCES (Permission denied)
> 
> Those were TCP sockets. Bind() fails because it happens after privilege
> drop.
> 
> --
>  .-.   .-.    Yes, I am an agent of Satan, but my duties are largely
> (_  \ /  _)   ceremonial.
>      |
>      |        [email protected]
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