diff options
author | Jonathan McCrohan <jmccrohan@gmail.com> | 2012-02-05 19:04:33 +0000 |
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committer | Jonathan McCrohan <jmccrohan@gmail.com> | 2012-02-05 19:04:33 +0000 |
commit | f3410da7f0bd208a5f2d792131b215454e782e93 (patch) | |
tree | 6e79c9acde383b91f5f21eb3a72f33e9c7fbbfce /iw_scan.c | |
parent | 03dfbc2efa31d3c4fd7e576111883ea488e3e179 (diff) | |
download | wavemon-f3410da7f0bd208a5f2d792131b215454e782e93.tar.gz |
Imported Upstream version 0.7.3upstream/0.7.3
Diffstat (limited to 'iw_scan.c')
-rw-r--r-- | iw_scan.c | 671 |
1 files changed, 671 insertions, 0 deletions
diff --git a/iw_scan.c b/iw_scan.c new file mode 100644 index 0000000..e055acb --- /dev/null +++ b/iw_scan.c @@ -0,0 +1,671 @@ +/* + * Auxiliary declarations and functions imported from iwlib in order to + * process and parse scan events. This code is copied with little change + * from wireless tools 30. It remains here until the wext code will be + * replaced by corresponding netlink calls. + */ +#include "iw_if.h" + +#define MAX_SCAN_WAIT 10000 /* maximum milliseconds spent waiting */ + +/* + * Meta-data about all the additional standard Wireless Extension events + * we know about. + */ +/* Type of headers we know about (basically union iwreq_data) */ +#define IW_HEADER_TYPE_NULL 0 /* Not available */ +#define IW_HEADER_TYPE_CHAR 2 /* char [IFNAMSIZ] */ +#define IW_HEADER_TYPE_UINT 4 /* __u32 */ +#define IW_HEADER_TYPE_FREQ 5 /* struct iw_freq */ +#define IW_HEADER_TYPE_ADDR 6 /* struct sockaddr */ +#define IW_HEADER_TYPE_POINT 8 /* struct iw_point */ +#define IW_HEADER_TYPE_PARAM 9 /* struct iw_param */ +#define IW_HEADER_TYPE_QUAL 10 /* struct iw_quality */ + +/* Size (in bytes) of various events */ +static const int event_type_size[] = { + [IW_HEADER_TYPE_NULL] = IW_EV_LCP_PK_LEN, + [IW_HEADER_TYPE_CHAR] = IW_EV_CHAR_PK_LEN, + [IW_HEADER_TYPE_UINT] = IW_EV_UINT_PK_LEN, + [IW_HEADER_TYPE_FREQ] = IW_EV_FREQ_PK_LEN, + [IW_HEADER_TYPE_ADDR] = IW_EV_ADDR_PK_LEN, + /* + * Fix IW_EV_POINT_PK_LEN: some wireless.h versions define this + * erroneously as IW_EV_LCP_LEN + 4 (e.g. ESSID will disappear). + * The value below is from wireless tools 30. + */ + [IW_HEADER_TYPE_POINT] = IW_EV_LCP_PK_LEN + 4, + [IW_HEADER_TYPE_PARAM] = IW_EV_PARAM_PK_LEN, + [IW_HEADER_TYPE_QUAL] = IW_EV_QUAL_PK_LEN +}; + +/* Handling flags */ +#define IW_DESCR_FLAG_NONE 0x0000 /* Obvious */ +/* Wrapper level flags */ +#define IW_DESCR_FLAG_DUMP 0x0001 /* Not part of the dump command */ +#define IW_DESCR_FLAG_EVENT 0x0002 /* Generate an event on SET */ +#define IW_DESCR_FLAG_RESTRICT 0x0004 /* GET : request is ROOT only */ + /* SET : Omit payload from generated iwevent */ +#define IW_DESCR_FLAG_NOMAX 0x0008 /* GET : no limit on request size */ +/* Driver level flags */ +#define IW_DESCR_FLAG_WAIT 0x0100 /* Wait for driver event */ + +struct iw_ioctl_description { + __u8 header_type; /* NULL, iw_point or other */ + __u8 token_type; /* Future */ + __u16 token_size; /* Granularity of payload */ + __u16 min_tokens; /* Min acceptable token number */ + __u16 max_tokens; /* Max acceptable token number */ + __u32 flags; /* Special handling of the request */ +}; + +/* + * Meta-data about all the standard Wireless Extension request we + * know about. + */ +static const struct iw_ioctl_description standard_ioctl_descr[] = { + [SIOCSIWCOMMIT - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_NULL, + }, + [SIOCGIWNAME - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_CHAR, + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWNWID - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + .flags = IW_DESCR_FLAG_EVENT, + }, + [SIOCGIWNWID - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWFREQ - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_FREQ, + .flags = IW_DESCR_FLAG_EVENT, + }, + [SIOCGIWFREQ - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_FREQ, + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWMODE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_UINT, + .flags = IW_DESCR_FLAG_EVENT, + }, + [SIOCGIWMODE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_UINT, + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWSENS - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWSENS - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCSIWRANGE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_NULL, + }, + [SIOCGIWRANGE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = sizeof(struct iw_range), + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWPRIV - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_NULL, + }, + [SIOCGIWPRIV - SIOCIWFIRST] = { /* (handled directly by us) */ + .header_type = IW_HEADER_TYPE_NULL, + }, + [SIOCSIWSTATS - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_NULL, + }, + [SIOCGIWSTATS - SIOCIWFIRST] = { /* (handled directly by us) */ + .header_type = IW_HEADER_TYPE_NULL, + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWSPY - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = sizeof(struct sockaddr), + .max_tokens = IW_MAX_SPY, + }, + [SIOCGIWSPY - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = sizeof(struct sockaddr) + + sizeof(struct iw_quality), + .max_tokens = IW_MAX_SPY, + }, + [SIOCSIWTHRSPY - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = sizeof(struct iw_thrspy), + .min_tokens = 1, + .max_tokens = 1, + }, + [SIOCGIWTHRSPY - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = sizeof(struct iw_thrspy), + .min_tokens = 1, + .max_tokens = 1, + }, + [SIOCSIWAP - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_ADDR, + }, + [SIOCGIWAP - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_ADDR, + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWMLME - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .min_tokens = sizeof(struct iw_mlme), + .max_tokens = sizeof(struct iw_mlme), + }, + [SIOCGIWAPLIST - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = sizeof(struct sockaddr) + + sizeof(struct iw_quality), + .max_tokens = IW_MAX_AP, + .flags = IW_DESCR_FLAG_NOMAX, + }, + [SIOCSIWSCAN - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .min_tokens = 0, + .max_tokens = sizeof(struct iw_scan_req), + }, + [SIOCGIWSCAN - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_SCAN_MAX_DATA, + .flags = IW_DESCR_FLAG_NOMAX, + }, + [SIOCSIWESSID - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_ESSID_MAX_SIZE + 1, + .flags = IW_DESCR_FLAG_EVENT, + }, + [SIOCGIWESSID - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_ESSID_MAX_SIZE + 1, + .flags = IW_DESCR_FLAG_DUMP, + }, + [SIOCSIWNICKN - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_ESSID_MAX_SIZE + 1, + }, + [SIOCGIWNICKN - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_ESSID_MAX_SIZE + 1, + }, + [SIOCSIWRATE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWRATE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCSIWRTS - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWRTS - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCSIWFRAG - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWFRAG - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCSIWTXPOW - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWTXPOW - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCSIWRETRY - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWRETRY - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCSIWENCODE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_ENCODING_TOKEN_MAX, + .flags = IW_DESCR_FLAG_EVENT | IW_DESCR_FLAG_RESTRICT, + }, + [SIOCGIWENCODE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_ENCODING_TOKEN_MAX, + .flags = IW_DESCR_FLAG_DUMP | IW_DESCR_FLAG_RESTRICT, + }, + [SIOCSIWPOWER - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWPOWER - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, +#ifdef SIOCSIWMODUL + [SIOCSIWMODUL - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, +#endif +#ifdef SIOCGIWMODUL + [SIOCGIWMODUL - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, +#endif + [SIOCSIWGENIE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_GENERIC_IE_MAX, + }, + [SIOCGIWGENIE - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_GENERIC_IE_MAX, + }, + [SIOCSIWAUTH - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCGIWAUTH - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_PARAM, + }, + [SIOCSIWENCODEEXT - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .min_tokens = sizeof(struct iw_encode_ext), + .max_tokens = sizeof(struct iw_encode_ext) + + IW_ENCODING_TOKEN_MAX, + }, + [SIOCGIWENCODEEXT - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .min_tokens = sizeof(struct iw_encode_ext), + .max_tokens = sizeof(struct iw_encode_ext) + + IW_ENCODING_TOKEN_MAX, + }, + [SIOCSIWPMKSA - SIOCIWFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .min_tokens = sizeof(struct iw_pmksa), + .max_tokens = sizeof(struct iw_pmksa), + }, +}; + +static const struct iw_ioctl_description standard_event_descr[] = { + [IWEVTXDROP - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_ADDR, + }, + [IWEVQUAL - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_QUAL, + }, + [IWEVCUSTOM - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_CUSTOM_MAX, + }, + [IWEVREGISTERED - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_ADDR, + }, + [IWEVEXPIRED - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_ADDR, + }, + [IWEVGENIE - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_GENERIC_IE_MAX, + }, + [IWEVMICHAELMICFAILURE - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = sizeof(struct iw_michaelmicfailure), + }, + [IWEVASSOCREQIE - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_GENERIC_IE_MAX, + }, + [IWEVASSOCRESPIE - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = IW_GENERIC_IE_MAX, + }, + [IWEVPMKIDCAND - IWEVFIRST] = { + .header_type = IW_HEADER_TYPE_POINT, + .token_size = 1, + .max_tokens = sizeof(struct iw_pmkid_cand), + }, +}; + +struct stream_descr { + char *current; /* Current event in stream of events */ + char *value; /* Current value in event */ + char *end; /* End of the stream */ +}; + +/* + * Extract the next event from the event stream. + */ +static int iw_extract_event_stream(struct stream_descr *stream, + struct iw_event *iwe, int we_version) +{ + const struct iw_ioctl_description *descr = NULL; + int event_type; + unsigned int event_len = 1; /* Invalid */ + unsigned cmd_index; /* *MUST* be unsigned */ + char *pointer; + + if (stream->current + IW_EV_LCP_PK_LEN > stream->end) + return 0; + + /* Extract the event header to get the event id. + * Note : the event may be unaligned, therefore copy... */ + memcpy((char *)iwe, stream->current, IW_EV_LCP_PK_LEN); + + if (iwe->len <= IW_EV_LCP_PK_LEN) + return -1; + + /* Get the type and length of that event */ + if (iwe->cmd <= SIOCIWLAST) { + cmd_index = iwe->cmd - SIOCIWFIRST; + if (cmd_index < ARRAY_SIZE(standard_ioctl_descr)) + descr = standard_ioctl_descr + cmd_index; + } else { + cmd_index = iwe->cmd - IWEVFIRST; + if (cmd_index < ARRAY_SIZE(standard_event_descr)) + descr = standard_event_descr + cmd_index; + } + + /* Unknown events -> event_type = 0 => IW_EV_LCP_PK_LEN */ + event_type = descr ? descr->header_type : 0; + event_len = event_type_size[event_type]; + + /* Check if we know about this event */ + if (event_len <= IW_EV_LCP_PK_LEN) { + stream->current += iwe->len; /* Skip to next event */ + return 2; + } + event_len -= IW_EV_LCP_PK_LEN; + + /* Fixup for earlier version of WE */ + if (we_version <= 18 && event_type == IW_HEADER_TYPE_POINT) + event_len += IW_EV_POINT_OFF; + + if (stream->value != NULL) + pointer = stream->value; /* Next value in event */ + else + pointer = stream->current + IW_EV_LCP_PK_LEN; /* First value in event */ + + /* Copy the rest of the event (at least, fixed part) */ + if (pointer + event_len > stream->end) { + stream->current += iwe->len; /* Skip to next event */ + return -2; + } + + /* Fixup for WE-19 and later: pointer no longer in the stream */ + /* Beware of alignment. Dest has local alignment, not packed */ + if (we_version > 18 && event_type == IW_HEADER_TYPE_POINT) + memcpy((char *)iwe + IW_EV_LCP_LEN + IW_EV_POINT_OFF, pointer, event_len); + else + memcpy((char *)iwe + IW_EV_LCP_LEN, pointer, event_len); + + /* Skip event in the stream */ + pointer += event_len; + + /* Special processing for iw_point events */ + if (event_type == IW_HEADER_TYPE_POINT) { + unsigned int extra_len = iwe->len - (event_len + IW_EV_LCP_PK_LEN); + + if (extra_len > 0) { + /* Set pointer on variable part (warning : non aligned) */ + iwe->u.data.pointer = pointer; + + /* Check that we have a descriptor for the command */ + if (descr == NULL) { + /* Can't check payload -> unsafe... */ + iwe->u.data.pointer = NULL; /* Discard paylod */ + } else { + unsigned int token_len = iwe->u.data.length * descr->token_size; + /* + * Ugly fixup for alignment issues. + * If the kernel is 64 bits and userspace 32 bits, we have an extra 4 + 4 + * bytes. Fixing that in the kernel would break 64 bits userspace. + */ + if (token_len != extra_len && extra_len >= 4) { + union iw_align_u16 { + __u16 value; + unsigned char byte[2]; + } alt_dlen; + unsigned int alt_token_len; + + /* Userspace seems to not always like unaligned access, + * so be careful and make sure to align value. + * I hope gcc won't play any of its aliasing tricks... */ + alt_dlen.byte[0] = *(pointer); + alt_dlen.byte[1] = *(pointer + 1); + alt_token_len = alt_dlen.value * descr->token_size; + + /* Verify that data is consistent if assuming 64 bit alignment... */ + if (alt_token_len + 8 == extra_len) { + + /* Ok, let's redo everything */ + pointer -= event_len; + pointer += 4; + + /* Dest has local alignment, not packed */ + memcpy((char *)iwe + IW_EV_LCP_LEN + IW_EV_POINT_OFF, pointer, event_len); + pointer += event_len + 4; + token_len = alt_token_len; + + /* We may have no payload */ + if (alt_token_len) + iwe->u.data.pointer = pointer; + else + iwe->u.data.pointer = NULL; + } + } + + /* Discard bogus events which advertise more tokens than they carry ... */ + if (token_len > extra_len) + iwe->u.data.pointer = NULL; /* Discard paylod */ + + /* Check that the advertised token size is not going to + * produce buffer overflow to our caller... */ + if (iwe->u.data.length > descr->max_tokens + && !(descr->flags & IW_DESCR_FLAG_NOMAX)) + iwe->u.data.pointer = NULL; /* Discard payload */ + + /* Same for underflows... */ + if (iwe->u.data.length < descr->min_tokens) + iwe->u.data.pointer = NULL; /* Discard paylod */ + } + } else { + /* No data */ + iwe->u.data.pointer = NULL; + } + + stream->current += iwe->len; /* Go to next event */ + } else { + /* + * Ugly fixup for alignment issues. + * If the kernel is 64 bits and userspace 32 bits, we have an extra 4 bytes. + * Fixing that in the kernel would break 64 bits userspace. + */ + if (stream->value == NULL && + ((iwe->len - IW_EV_LCP_PK_LEN) % event_len == 4 || + (iwe->len == 12 && (event_type == IW_HEADER_TYPE_UINT || + event_type == IW_HEADER_TYPE_QUAL)))) { + + pointer -= event_len; + pointer += 4; + + /* Beware of alignment. Dest has local alignment, not packed */ + memcpy((char *)iwe + IW_EV_LCP_LEN, pointer, event_len); + pointer += event_len; + } + + if (pointer + event_len <= stream->current + iwe->len) { + stream->value = pointer; /* Go to next value */ + } else { + stream->value = NULL; + stream->current += iwe->len; /* Go to next event */ + } + } + return 1; +} + +static void iw_extract_ie(struct iw_event *iwe, struct scan_result *sr) +{ + const uint8_t wpa1_oui[3] = { 0x00, 0x50, 0xf2 }; + uint8_t *buffer = iwe->u.data.pointer; + int ielen = 0, ietype, i; + + /* Loop on each IE, each is min. 2 bytes TLV: IE-ID - Length - Value */ + for (i = 0; i <= iwe->u.data.length - 2; i += ielen + 2) { + ietype = buffer[i]; + ielen = buffer[i + 1]; + + switch (ietype) { + case 0x30: + if (ielen < 4) /* make sure we have enough data */ + continue; + sr->flags |= IW_ENC_CAPA_WPA2; + break; + case 0xdd: + /* Not all IEs that start with 0xdd are WPA1 */ + if (ielen < 8 || memcmp(buffer + i + 2, wpa1_oui, 3) || + buffer[i + 5] != 1) + continue; + sr->flags |= IW_ENC_CAPA_WPA; + break; + } + } +} +/*----------------- End of code copied from iwlib -----------------------*/ + +/* Order by descending signal strength. */ +extern int cmp_sig(const struct scan_result *a, const struct scan_result *b) +{ + return a->qual.level - b->qual.level; +} + +/* Order by ascending frequency first, then by descending signal strength. */ +extern int cmp_freq_sig(const struct scan_result *a, const struct scan_result *b) +{ + return a->freq == b->freq ? cmp_sig(a, b) : a->freq < b->freq; +} + +struct scan_result *get_scan_list(int skfd, const char *ifname, int we_version, + scan_cmp_func cmp_scan_result) +{ + struct scan_result *head = NULL; + struct iwreq wrq; + int wait, waited = 0; + + /* + * Some drivers may return very large scan results, either because there + * are many cells, or there are many large elements. Do not bother to + * guess buffer size, use maximum u16 wrq.u.data.length size. + */ + char scan_buf[0xffff]; + + /* We are checking errno when returning NULL, so reset it here */ + errno = 0; + + memset(&wrq, 0, sizeof(wrq)); + strncpy(wrq.ifr_ifrn.ifrn_name, ifname, IFNAMSIZ); + if (ioctl(skfd, SIOCSIWSCAN, &wrq) < 0) + return NULL; + + /* Larger initial timeout of 250ms between set and first get */ + for (wait = 250; (waited += wait) < MAX_SCAN_WAIT; wait = 100) { + struct timeval tv = { 0, wait * 1000 }; + + while (select(0, NULL, NULL, NULL, &tv) < 0) + if (errno != EINTR && errno != EAGAIN) + return NULL; + + wrq.u.data.pointer = scan_buf; + wrq.u.data.length = sizeof(scan_buf); + wrq.u.data.flags = 0; + + if (ioctl(skfd, SIOCGIWSCAN, &wrq) == 0) + break; + } + + if (wrq.u.data.length) { + struct iw_event iwe; + struct stream_descr stream; + struct scan_result *new = NULL; + int f = 0; /* Idea taken from waproamd */ + + memset(&stream, 0, sizeof(stream)); + stream.current = scan_buf; + stream.end = scan_buf + wrq.u.data.length; + + while (iw_extract_event_stream(&stream, &iwe, we_version) > 0) { + if (!new) + new = calloc(1, sizeof(*new)); + + switch (iwe.cmd) { + case SIOCGIWAP: + f = 1; + memcpy(&new->ap_addr, &iwe.u.ap_addr.sa_data, sizeof(new->ap_addr)); + break; + case SIOCGIWESSID: + f |= 2; + memset(new->essid, 0, sizeof(new->essid)); + + if (iwe.u.essid.flags && iwe.u.essid.pointer && iwe.u.essid.length) + memcpy(new->essid, iwe.u.essid.pointer, iwe.u.essid.length); + break; + case SIOCGIWMODE: + new->mode = iwe.u.mode; + f |= 4; + break; + case SIOCGIWFREQ: + f |= 8; + new->freq = freq_to_hz(&iwe.u.freq); + break; + case SIOCGIWENCODE: + f |= 16; + new->has_key = !(iwe.u.data.flags & IW_ENCODE_DISABLED); + break; + case IWEVQUAL: + f |= 32; + memcpy(&new->qual, &iwe.u.qual, sizeof(struct iw_quality)); + break; + case IWEVGENIE: + f |= 64; + iw_extract_ie(&iwe, new); + break; + } + if (f == 127) { + struct scan_result *cur = head, **prev = &head; + + f = 0; + + while (cur && cmp_scan_result(cur, new) > 0) + prev = &cur->next, cur = cur->next; + + *prev = new; + new->next = cur; + new = NULL; + } + } + free(new); /* may have been allocated but not filled in */ + } + return head; +} + +void free_scan_result(struct scan_result *head) +{ + if (head) { + free_scan_result(head->next); + free(head); + } +} |