[src/trunk]: src/sbin/ifconfig fix bugs in ssid printing

[christos <christos%NetBSD.org@localhost>]

details:   https://anonhg.NetBSD.org/src/rev/e057fe9e845e
branches:  trunk
changeset: 347920:e057fe9e845e
user:      christos <christos%NetBSD.org@localhost>
date:      Thu Sep 22 18:22:51 2016 +0000

description:
fix bugs in ssid printing

diffstat:

 sbin/ifconfig/ieee80211.c |  71 +++++++++++++++++++++++++++++++---------------
 1 files changed, 48 insertions(+), 23 deletions(-)

diffs (149 lines):

diff -r 7599d96f8839 -r e057fe9e845e sbin/ifconfig/ieee80211.c
--- a/sbin/ifconfig/ieee80211.c Thu Sep 22 17:08:16 2016 +0000
+++ b/sbin/ifconfig/ieee80211.c Thu Sep 22 18:22:51 2016 +0000
@@ -1,4 +1,4 @@
-/*     $NetBSD: ieee80211.c,v 1.28 2015/04/28 15:14:57 christos Exp $  */
+/*     $NetBSD: ieee80211.c,v 1.29 2016/09/22 18:22:51 christos Exp $  */
 
 /*
  * Copyright (c) 1983, 1993
@@ -31,7 +31,7 @@
 
 #include <sys/cdefs.h>
 #ifndef lint
-__RCSID("$NetBSD: ieee80211.c,v 1.28 2015/04/28 15:14:57 christos Exp $");
+__RCSID("$NetBSD: ieee80211.c,v 1.29 2016/09/22 18:22:51 christos Exp $");
 #endif /* not lint */
 
 #include <sys/param.h>
@@ -765,14 +765,36 @@
        prog_close(sroute);
 }
 
+static int
+calc_len(const u_int8_t *cp, int len)
+{
+       int maxlen = 0, curlen;
+       const struct ieee80211req_scan_result *sr;
+       char buf[IEEE80211_NWID_LEN];
+
+       while (len >= (int)sizeof(*sr)) {
+               sr = (const struct ieee80211req_scan_result *)cp;
+               cp += sr->isr_len;
+               len -= sr->isr_len;
+               curlen = copy_essid(buf, sizeof(buf),
+                   (const u_int8_t *)(sr + 1), sr->isr_ssid_len);
+               if (curlen >= IEEE80211_NWID_LEN)
+                       return IEEE80211_NWID_LEN;
+               if (curlen > maxlen)
+                       maxlen = curlen;
+       }
+       return maxlen;
+}
+
 static void
 list_scan(prop_dictionary_t env)
 {
-       u_int8_t buf[24*1024];
+       u_int8_t buf[64*1024 - 1];
        struct ieee80211req ireq;
        char ssid[IEEE80211_NWID_LEN+1];
        const u_int8_t *cp;
        int len, ssidmax;
+       const struct ieee80211req_scan_result *sr;
 
        memset(&ireq, 0, sizeof(ireq));
        ireq.i_type = IEEE80211_IOC_SCAN_RESULTS;
@@ -781,10 +803,11 @@
        if (direct_ioctl(env, SIOCG80211, &ireq) < 0)
                errx(EXIT_FAILURE, "unable to get scan results");
        len = ireq.i_len;
-       if (len < (int)sizeof(struct ieee80211req_scan_result))
+       if (len < (int)sizeof(*sr))
                return;
 
-       ssidmax = IEEE80211_NWID_LEN;
+       ssidmax = calc_len(buf, len);
+
        printf("%-*.*s  %-17.17s  %4s %4s  %-7s %3s %4s\n"
                , ssidmax, ssidmax, "SSID"
                , "BSSID"
@@ -795,16 +818,14 @@
                , "CAPS"
        );
        cp = buf;
-       do {
-               const struct ieee80211req_scan_result *sr;
+       while (len >= (int)sizeof(*sr)) {
                const uint8_t *vp;
 
                sr = (const struct ieee80211req_scan_result *) cp;
                vp = (const u_int8_t *)(sr+1);
+               (void)copy_essid(ssid, sizeof(ssid), vp, sr->isr_ssid_len);
                printf("%-*.*s  %s  %3d  %3dM %3d:%-3d  %3d %-4.4s"
-                       , ssidmax
-                         , copy_essid(ssid, ssidmax, vp, sr->isr_ssid_len)
-                         , ssid
+                       , ssidmax, ssidmax, ssid
                        , ether_ntoa((const struct ether_addr *) sr->isr_bssid)
                        , ieee80211_mhz2ieee(sr->isr_freq, sr->isr_flags)
                        , getmaxrate(sr->isr_rates, sr->isr_nrates)
@@ -815,7 +836,7 @@
                printies(vp + sr->isr_ssid_len, sr->isr_ie_len, 24);
                printf("\n");
                cp += sr->isr_len, len -= sr->isr_len;
-       } while (len >= (int)sizeof(struct ieee80211req_scan_result));
+       }
 }
 /*
  * Convert MHz frequency to IEEE channel number.
@@ -1144,18 +1165,22 @@
 copy_essid(char buf[], size_t bufsize, const u_int8_t *essid, size_t essid_len)
 {
        const u_int8_t *p;
+       int printable;
        size_t maxlen, i;
 
-       if (essid_len > bufsize)
+       if (essid_len + 1 > bufsize)
                maxlen = bufsize;
        else
-               maxlen = essid_len;
+               maxlen = essid_len + 1;
        /* determine printable or not */
-       for (i = 0, p = essid; i < maxlen; i++, p++) {
-               if (*p < ' ' || *p > 0x7e)
+       printable = 1;
+       for (i = 0, p = essid; i < essid_len; i++, p++) {
+               if (*p < ' ' || *p > 0x7e) {
+                       printable = 0;
                        break;
+               }
        }
-       if (i != maxlen) {              /* not printable, print as hex */
+       if (!printable) {               /* not printable, print as hex */
                if (bufsize < 3)
                        return 0;
                strlcpy(buf, "0x", bufsize);
@@ -1165,14 +1190,14 @@
                        sprintf(&buf[2+2*i], "%02x", p[i]);
                        bufsize -= 2;
                }
-               if (i != essid_len)
-                       memcpy(&buf[2+2*i-3], "...", 3);
-       } else {                        /* printable, truncate as needed */
-               memcpy(buf, essid, maxlen);
-               if (maxlen != essid_len)
-                       memcpy(&buf[maxlen-3], "...", 3);
+               maxlen = i;
+       } else{
+               /* printable, truncate as needed */
+               strlcpy(buf, (const char *)essid, maxlen);
        }
-       return maxlen;
+       if (maxlen != essid_len + 1)
+               memcpy(&buf[maxlen - 4], "...", 4);
+       return (int)strlen(buf);
 }
 
 static void