diff options
Diffstat (limited to 'native/net_monitor.c')
| -rw-r--r-- | native/net_monitor.c | 229 |
1 files changed, 229 insertions, 0 deletions
diff --git a/native/net_monitor.c b/native/net_monitor.c new file mode 100644 index 0000000..2594a65 --- /dev/null +++ b/native/net_monitor.c @@ -0,0 +1,229 @@ +#include <Python.h> +#include <string.h> +#include <fcntl.h> +#include <sys/ioctl.h> +#include <unistd.h> +#include <stdlib.h> +#include <stdio.h> +#ifndef __user +#define __user +#endif +#include <sys/types.h> +#include <linux/types.h> +#include <sys/socket.h> +#include <net/if.h> +#include <wireless.h> + +/************************ CONSTANTS & MACROS ************************/ + +/* + * Constants fof WE-9->15 + */ +#define IW15_MAX_FREQUENCIES 16 +#define IW15_MAX_BITRATES 8 +#define IW15_MAX_TXPOWER 8 +#define IW15_MAX_ENCODING_SIZES 8 +#define IW15_MAX_SPY 8 +#define IW15_MAX_AP 8 + +/* + * Struct iw_range up to WE-15 + */ +struct iw15_range +{ + __u32 throughput; + __u32 min_nwid; + __u32 max_nwid; + __u16 num_channels; + __u8 num_frequency; + struct iw_freq freq[IW15_MAX_FREQUENCIES]; + __s32 sensitivity; + struct iw_quality max_qual; + __u8 num_bitrates; + __s32 bitrate[IW15_MAX_BITRATES]; + __s32 min_rts; + __s32 max_rts; + __s32 min_frag; + __s32 max_frag; + __s32 min_pmp; + __s32 max_pmp; + __s32 min_pmt; + __s32 max_pmt; + __u16 pmp_flags; + __u16 pmt_flags; + __u16 pm_capa; + __u16 encoding_size[IW15_MAX_ENCODING_SIZES]; + __u8 num_encoding_sizes; + __u8 max_encoding_tokens; + __u16 txpower_capa; + __u8 num_txpower; + __s32 txpower[IW15_MAX_TXPOWER]; + __u8 we_version_compiled; + __u8 we_version_source; + __u16 retry_capa; + __u16 retry_flags; + __u16 r_time_flags; + __s32 min_retry; + __s32 max_retry; + __s32 min_r_time; + __s32 max_r_time; + struct iw_quality avg_qual; +}; + +/* + * Union for all the versions of iwrange. + * Fortunately, I mostly only add fields at the end, and big-bang + * reorganisations are few. + */ +union iw_range_raw +{ + struct iw15_range range15; /* WE 9->15 */ + struct iw_range range; /* WE 16->current */ +}; + +/* + * Offsets in iw_range struct + */ +#define iwr15_off(f) ( ((char *) &(((struct iw15_range *) NULL)->f)) - \ + (char *) NULL) +#define iwr_off(f) ( ((char *) &(((struct iw_range *) NULL)->f)) - \ + (char *) NULL) + +typedef struct iw_range iwrange; + +/*------------------------------------------------------------------*/ +/* + * Wrapper to extract some Wireless Parameter out of the driver + */ +static inline int +iw_get_ext(int skfd, /* Socket to the kernel */ + const char * ifname, /* Device name */ + int request, /* WE ID */ + struct iwreq * pwrq) /* Fixed part of the request */ +{ + /* Set device name */ + strncpy(pwrq->ifr_name, ifname, IFNAMSIZ); + /* Do the request */ + return(ioctl(skfd, request, pwrq)); +} +/*------------------------------------------------------------------*/ +/* + * Get the range information out of the driver + */ +int +iw_get_range_info(int skfd, const char *ifname, iwrange * range) +{ + struct iwreq wrq; + char buffer[sizeof(iwrange) * 2]; /* Large enough */ + union iw_range_raw * range_raw; + + /* Cleanup */ + bzero(buffer, sizeof(buffer)); + + wrq.u.data.pointer = (caddr_t) buffer; + wrq.u.data.length = sizeof(buffer); + wrq.u.data.flags = 0; + if(iw_get_ext(skfd, ifname, SIOCGIWRANGE, &wrq) < 0) + return(-1); + + /* Point to the buffer */ + range_raw = (union iw_range_raw *) buffer; + + /* For new versions, we can check the version directly, for old versions + * we use magic. 300 bytes is a also magic number, don't touch... */ + if(wrq.u.data.length < 300) + { + /* That's v10 or earlier. Ouch ! Let's make a guess...*/ + range_raw->range.we_version_compiled = 9; + } + + /* Check how it needs to be processed */ + if(range_raw->range.we_version_compiled > 15) + { + /* This is our native format, that's easy... */ + /* Copy stuff at the right place, ignore extra */ + memcpy((char *) range, buffer, sizeof(iwrange)); + } + else + { + /* Zero unknown fields */ + bzero((char *) range, sizeof(struct iw_range)); + + /* Initial part unmoved */ + memcpy((char *) range, + buffer, + iwr15_off(num_channels)); + /* Frequencies pushed futher down towards the end */ + memcpy((char *) range + iwr_off(num_channels), + buffer + iwr15_off(num_channels), + iwr15_off(sensitivity) - iwr15_off(num_channels)); + /* This one moved up */ + memcpy((char *) range + iwr_off(sensitivity), + buffer + iwr15_off(sensitivity), + iwr15_off(num_bitrates) - iwr15_off(sensitivity)); + /* This one goes after avg_qual */ + memcpy((char *) range + iwr_off(num_bitrates), + buffer + iwr15_off(num_bitrates), + iwr15_off(min_rts) - iwr15_off(num_bitrates)); + /* Number of bitrates has changed, put it after */ + memcpy((char *) range + iwr_off(min_rts), + buffer + iwr15_off(min_rts), + iwr15_off(txpower_capa) - iwr15_off(min_rts)); + /* Added encoding_login_index, put it after */ + memcpy((char *) range + iwr_off(txpower_capa), + buffer + iwr15_off(txpower_capa), + iwr15_off(txpower) - iwr15_off(txpower_capa)); + /* Hum... That's an unexpected glitch. Bummer. */ + memcpy((char *) range + iwr_off(txpower), + buffer + iwr15_off(txpower), + iwr15_off(avg_qual) - iwr15_off(txpower)); + /* Avg qual moved up next to max_qual */ + memcpy((char *) range + iwr_off(avg_qual), + buffer + iwr15_off(avg_qual), + sizeof(struct iw_quality)); + } + + return(0); +} + +static PyObject * + get_max_quality(PyObject *self, PyObject *args) +{ + const char *iface; + int max_quality; + int fd, err; + struct iw_range range; + + if (!PyArg_ParseTuple(args, "s", &iface)) + return NULL; + + fd = socket (PF_INET, SOCK_DGRAM, 0); + if (fd < 0) { + fprintf (stderr, "couldn't open socket\n"); + return NULL; + } + + err = iw_get_range_info(fd, iface, &range); + close (fd); + + if (err < 0) { + PyErr_SetFromErrno(PyExc_IOError); + return NULL; + } + max_quality = range.max_qual.qual; + return Py_BuildValue("i", max_quality); +} + +/* python module details */ +static PyMethodDef net_monitor_Methods[] = { + {"get_max_quality", get_max_quality, METH_VARARGS, + "Find maximum quality value for a wireless interface."}, + {NULL, NULL, 0, NULL} /* Sentinel */ +}; + +PyMODINIT_FUNC +initnet_monitor(void) +{ + (void) Py_InitModule("net_monitor", net_monitor_Methods); +} + |