utmpdump: make IPv6 addresses work

(unless bug[s]) This change is backwards compatibile.  Earlier binary to
text dumps can be converted back to binary, or otherway around.

The only thing that will not work are IPv6 addresses that possible
earlier conversion had broke.  Such conversions resulted with random IPv4
in place of IPv6 address in text format, and original information is gone
forever.

Signed-off-by: Sami Kerola <kerolasa@iki.fi>

diff --git a/login-utils/utmpdump.c b/login-utils/utmpdump.c
index acc10db16bb98067dec8814d1fe70d9dea4b2a0a..4451363fbc50faf1986de32749a1fbc6baa06dc9 100644 (file)
--- a/login-utils/utmpdump.c
+++ b/login-utils/utmpdump.c
@@ -85,11 +85,14 @@ static void xcleanse(char *s, int len)
 
 static void print_utline(struct utmp ut, FILE *out)
 {
-       char *addr_string, *time_string;
-       struct in_addr in;
+       const char *addr_string, *time_string;
+       char buffer[INET6_ADDRSTRLEN];
+
+       if (ut.ut_addr_v6[1] || ut.ut_addr_v6[2] || ut.ut_addr_v6[3])
+               addr_string = inet_ntop(AF_INET6, &(ut.ut_addr_v6), buffer, sizeof(buffer));
+       else
+               addr_string = inet_ntop(AF_INET, &(ut.ut_addr_v6), buffer, sizeof(buffer));
 
-       in.s_addr = ut.ut_addr;
-       addr_string = inet_ntoa(in);
 #if defined(_HAVE_UT_TV)
        time_string = timetostr(ut.ut_tv.tv_sec);
 #else
@@ -101,7 +104,7 @@ static void print_utline(struct utmp ut, FILE *out)
        cleanse(ut.ut_host);
 
        /*            pid    id       user     line     host     addr       time */
-       fprintf(out, "[%d] [%05d] [%-4.4s] [%-*.*s] [%-*.*s] [%-*.*s] [%-15.15s] [%-28.28s]\n",
+       fprintf(out, "[%d] [%05d] [%-4.4s] [%-*.*s] [%-*.*s] [%-*.*s] [%-15s] [%-28.28s]\n",
               ut.ut_type, ut.ut_pid, ut.ut_id, 8, UT_NAMESIZE, ut.ut_user,
               12, UT_LINESIZE, ut.ut_line, 20, UT_HOSTSIZE, ut.ut_host,
               addr_string, time_string);
@@ -252,11 +255,10 @@ static int gettok(char *line, char *dest, int size, int eatspace)
 static void undump(FILE *in, FILE *out)
 {
        struct utmp ut;
-       char s_addr[16], s_time[29], *linestart, *line;
+       char s_addr[INET6_ADDRSTRLEN + 1], s_time[29], *linestart, *line;
        int count = 0;
 
        linestart = xmalloc(1024 * sizeof(*linestart));
-       s_addr[15] = 0;
        s_time[28] = 0;
 
        while (fgets(linestart, 1023, in)) {
@@ -270,8 +272,10 @@ static void undump(FILE *in, FILE *out)
                line += gettok(line, ut.ut_host, sizeof(ut.ut_host), 1);
                line += gettok(line, s_addr, sizeof(s_addr) - 1, 1);
                gettok(line, s_time, sizeof(s_time) - 1, 0);
-
-               ut.ut_addr = inet_addr(s_addr);
+               if (strchr(s_addr, '.'))
+                       inet_pton(AF_INET, s_addr, &(ut.ut_addr_v6));
+               else
+                       inet_pton(AF_INET6, s_addr, &(ut.ut_addr_v6));
 #if defined(_HAVE_UT_TV)
                ut.ut_tv.tv_sec = strtotime(s_time);
 #else