+
+/* FreeBSD's inet_addr/inet_aton */
+
+/*
+* Check whether "cp" is a valid ASCII representation
+ * of an Internet address and convert to a binary address.
+ * Returns 1 if the address is valid, 0 if not.
+ * This replaces inet_addr, the return value from which
+ * cannot distinguish between failure and a local broadcast address.
+ */
+int
+inet_aton(cp, addr)
+register const char *cp;
+struct in_addr *addr;
+{
+ u_long parts[4];
+ in_addr_t val;
+ char *c;
+ char *endptr;
+ int gotend, n;
+
+ c = (char *)cp;
+ n = 0;
+ /*
+ * Run through the string, grabbing numbers until
+ * the end of the string, or some error
+ */
+ gotend = 0;
+ while (!gotend) {
+ errno = 0;
+ val = strtoul(c, &endptr, 0);
+
+ if (errno == ERANGE) /* Fail completely if it overflowed. */
+ return (0);
+
+ /*
+ * If the whole string is invalid, endptr will equal
+ * c.. this way we can make sure someone hasn't
+ * gone '.12' or something which would get past
+ * the next check.
+ */
+ if (endptr == c)
+ return (0);
+ parts[n] = val;
+ c = endptr;
+
+ /* Check the next character past the previous number's end */
+ switch (*c) {
+ case '.' :
+ /* Make sure we only do 3 dots .. */
+ if (n == 3) /* Whoops. Quit. */
+ return (0);
+ n++;
+ c++;
+ break;
+
+ case '\0':
+ gotend = 1;
+ break;
+
+ default:
+ if (isspace((unsigned char)*c)) {
+ gotend = 1;
+ break;
+ } else
+ return (0); /* Invalid character, so fail */
+ }
+
+ }
+
+ /*
+ * Concoct the address according to
+ * the number of parts specified.
+ */
+
+ switch (n) {
+ case 0: /* a -- 32 bits */
+ /*
+ * Nothing is necessary here. Overflow checking was
+ * already done in strtoul().
+ */
+ break;
+ case 1: /* a.b -- 8.24 bits */
+ if (val > 0xffffff || parts[0] > 0xff)
+ return (0);
+ val |= parts[0] << 24;
+ break;
+
+ case 2: /* a.b.c -- 8.8.16 bits */
+ if (val > 0xffff || parts[0] > 0xff || parts[1] > 0xff)
+ return (0);
+ val |= (parts[0] << 24) | (parts[1] << 16);
+ break;
+
+ case 3: /* a.b.c.d -- 8.8.8.8 bits */
+ if (val > 0xff || parts[0] > 0xff || parts[1] > 0xff ||
+ parts[2] > 0xff)
+ return (0);
+ val |= (parts[0] << 24) | (parts[1] << 16) | (parts[2] << 8);
+ break;
+ }
+
+ if (addr != NULL)
+ addr->s_addr = htonl(val);
+ return (1);
+}
+
+/*
+ * ASCII internet address interpretation routine.
+ * The value returned is in network order.
+ */
+in_addr_t /* XXX should be struct in_addr :( */
+inet_addr(cp)
+register const char *cp;
+{
+ struct in_addr val;
+
+ if (inet_aton(cp, &val))
+ return (val.s_addr);
+ return (INADDR_NONE);
+}
+
+int
+getgrouplist(uname, agroup, groups, grpcnt)
+const char *uname;
+gid_t agroup;
+register gid_t *groups;
+int *grpcnt;
+{
+ register struct group *grp;
+ register int i, ngroups;
+ int ret, maxgroups;
+
+ ret = 0;
+ ngroups = 0;
+ maxgroups = *grpcnt;
+ /*
+ * When installing primary group, duplicate it;
+ * the first element of groups is the effective gid
+ * and will be overwritten when a setgid file is executed.
+ */
+ groups[ngroups++] = agroup;
+ if (maxgroups > 1)
+ groups[ngroups++] = agroup;
+ /*
+ * Scan the group file to find additional groups.
+ */
+ setgrent();
+ while ((grp = getgrent())) {
+ for (i = 0; i < ngroups; i++) {
+ if (grp->gr_gid == groups[i])
+ goto skip;
+ }
+ for (i = 0; grp->gr_mem[i]; i++) {
+ if (!strcmp(grp->gr_mem[i], uname)) {
+ if (ngroups >= maxgroups) {
+ ret = -1;
+ break;
+ }
+ groups[ngroups++] = grp->gr_gid;
+ break;
+ }
+ }
+skip: ;
+ }
+ endgrent();
+ *grpcnt = ngroups;
+ return (ret);
+}
+
+int
+initgroups(uname, agroup)
+const char *uname;
+gid_t agroup;
+{
+ gid_t groups[32], ngroups;
+
+ ngroups = 32;
+ getgrouplist(uname, agroup, groups, &ngroups);
+ return (setgroups(ngroups, groups));
+}