.TH "LibrarySetup" 3 "Thu Jan 28 2021" "Version 1.0.5" "libnetfilter_queue" \" -*- nroff -*-
.ad l
.nh
.SH NAME
LibrarySetup \- Library setup [DEPRECATED]
.SH SYNOPSIS
.br
.PP
.SS "Functions"

.in +1c
.ti -1c
.RI "struct nfq_handle * \fBnfq_open\fP (void)"
.br
.ti -1c
.RI "int \fBnfq_close\fP (struct nfq_handle *h)"
.br
.ti -1c
.RI "int \fBnfq_bind_pf\fP (struct nfq_handle *h, uint16_t pf)"
.br
.ti -1c
.RI "int \fBnfq_unbind_pf\fP (struct nfq_handle *h, uint16_t pf)"
.br
.in -1c
.SH "Detailed Description"
.PP 
Library initialisation is made in two steps\&.
.PP
First step is to call \fBnfq_open()\fP to open a NFQUEUE handler\&.
.PP
Second step is to tell the kernel that userspace queueing is handle by NFQUEUE for the selected protocol\&. This is made by calling \fBnfq_unbind_pf()\fP and \fBnfq_bind_pf()\fP with protocol information\&. The idea behind this is to enable simultaneously loaded modules to be used for queuing\&.
.PP
Here's a little code snippet that bind with AF_INET: 
.PP
.nf
        h = nfq_open();
        if (!h) {
                fprintf(stderr, "error during nfq_open()\n");
                exit(1);
        }

        printf("unbinding existing nf_queue handler for AF_INET (if any)\n");
        if (nfq_unbind_pf(h, AF_INET) < 0) {
                fprintf(stderr, "error during nfq_unbind_pf()\n");
                exit(1);
        }

        printf("binding nfnetlink_queue as nf_queue handler for AF_INET\n");
        if (nfq_bind_pf(h, AF_INET) < 0) {
                fprintf(stderr, "error during nfq_bind_pf()\n");
                exit(1);
        }

.fi
.PP
 Once this is done, you can setup and use a \fBQueue\fP\&.
.PP
When the program has finished with libnetfilter_queue, it has to call the \fBnfq_close()\fP function to free all associated resources\&. 
.SH "Function Documentation"
.PP 
.SS "int nfq_bind_pf (struct nfq_handle * h, uint16_t pf)"
nfq_bind_pf - bind a nfqueue handler to a given protocol family 
.PP
\fBParameters\fP
.RS 4
\fIh\fP Netfilter queue connection handle obtained via call to \fBnfq_open()\fP 
.br
\fIpf\fP protocol family to bind to nfqueue handler obtained from \fBnfq_open()\fP
.RE
.PP
Binds the given queue connection handle to process packets belonging to the given protocol family (ie\&. PF_INET, PF_INET6, etc)\&. This call is obsolete, Linux kernels from 3\&.8 onwards ignore it\&.
.PP
\fBReturns\fP
.RS 4
integer inferior to 0 in case of failure 
.RE
.PP

.PP
Definition at line 474 of file libnetfilter_queue\&.c\&.
.SS "int nfq_close (struct nfq_handle * h)"
nfq_close - close a nfqueue handler 
.PP
\fBParameters\fP
.RS 4
\fIh\fP Netfilter queue connection handle obtained via call to \fBnfq_open()\fP
.RE
.PP
This function closes the nfqueue handler and free associated resources\&.
.PP
\fBReturns\fP
.RS 4
0 on success, non-zero on failure\&. 
.RE
.PP

.PP
Definition at line 452 of file libnetfilter_queue\&.c\&.
.SS "struct nfq_handle* nfq_open (void)"
nfq_open - open a nfqueue handler
.PP
This function obtains a netfilter queue connection handle\&. When you are finished with the handle returned by this function, you should destroy it by calling \fBnfq_close()\fP\&. A new netlink connection is obtained internally and associated with the queue connection handle returned\&.
.PP
\fBReturns\fP
.RS 4
a pointer to a new queue handle or NULL on failure\&. 
.RE
.PP

.PP
Definition at line 363 of file libnetfilter_queue\&.c\&.
.SS "int nfq_unbind_pf (struct nfq_handle * h, uint16_t pf)"
nfq_unbind_pf - unbind nfqueue handler from a protocol family 
.PP
\fBParameters\fP
.RS 4
\fIh\fP Netfilter queue connection handle obtained via call to \fBnfq_open()\fP 
.br
\fIpf\fP protocol family to unbind family from
.RE
.PP
Unbinds the given queue connection handle from processing packets belonging to the given protocol family\&.
.PP
This call is obsolete, Linux kernels from 3\&.8 onwards ignore it\&. 
.PP
Definition at line 490 of file libnetfilter_queue\&.c\&.
.SH "Author"
.PP 
Generated automatically by Doxygen for libnetfilter_queue from the source code\&.