libexport.a: Prepare to recognize IPv6 addresses in client_gettype()

[nfs-utils.git] / support / export / client.c

diff --git a/support/export/client.c b/support/export/client.c
index 9a0fc9dabd1f58068a46cfea13d41838e618a830..3e797c94f3d024f417ad54aefc74076732268e06 100644 (file)
--- a/support/export/client.c
+++ b/support/export/client.c
@@ -134,9 +134,13 @@ client_add(nfs_client *clp)
        *cpp = clp;
 }
 
-/* if canonical is set, then we *know* this is already a canonical name
- * so hostname lookup is avoided.
- * This is used when reading /proc/fs/nfs/exports
+/**
+ * client_lookup - look for @hname in our list of cached nfs_clients
+ * @hname: '\0'-terminated ASCII string containing hostname to look for
+ * @canonical: if set, @hname is known to be canonical DNS name
+ *
+ * Returns pointer to a matching or freshly created nfs_client.  NULL
+ * is returned if some problem occurs.
  */
 nfs_client *
 client_lookup(char *hname, int canonical)
@@ -215,6 +219,10 @@ client_dup(const nfs_client *clp, const struct addrinfo *ai)
        return new;
 }
 
+/**
+ * client_release - drop a reference to an nfs_client record
+ *
+ */
 void
 client_release(nfs_client *clp)
 {
@@ -223,6 +231,10 @@ client_release(nfs_client *clp)
        clp->m_count--;
 }
 
+/**
+ * client_freeall - deallocate all nfs_client records
+ *
+ */
 void
 client_freeall(void)
 {
@@ -478,43 +490,65 @@ static int
 check_netgroup(const nfs_client *clp, const struct addrinfo *ai)
 {
        const char *netgroup = clp->m_hostname + 1;
-       const char *hname = ai->ai_canonname;
        struct addrinfo *tmp = NULL;
        struct hostent *hp;
+       char *dot, *hname;
        int i, match;
-       char *dot;
+
+       match = 0;
+
+       hname = strdup(ai->ai_canonname);
+       if (hname == NULL) {
+               xlog(D_GENERAL, "%s: no memory for strdup", __func__);
+               goto out;
+       }
 
        /* First, try to match the hostname without
         * splitting off the domain */
-       if (innetgr(netgroup, hname, NULL, NULL))
-               return 1;
+       if (innetgr(netgroup, hname, NULL, NULL)) {
+               match = 1;
+               goto out;
+       }
 
        /* See if hname aliases listed in /etc/hosts or nis[+]
         * match the requested netgroup */
        hp = gethostbyname(hname);
        if (hp != NULL) {
                for (i = 0; hp->h_aliases[i]; i++)
-                       if (innetgr(netgroup, hp->h_aliases[i], NULL, NULL))
-                               return 1;
+                       if (innetgr(netgroup, hp->h_aliases[i], NULL, NULL)) {
+                               match = 1;
+                               goto out;
+                       }
        }
 
-       /* If hname is ip address convert to FQDN */
+       /* If hname happens to be an IP address, convert it
+        * to a the canonical DNS name bound to this address. */
        tmp = host_pton(hname);
        if (tmp != NULL) {
+               char *cname = host_canonname(tmp->ai_addr);
                freeaddrinfo(tmp);
-               if (innetgr(netgroup, hname, NULL, NULL))
-                       return 1;
+
+               /* The resulting FQDN may be in our netgroup. */
+               if (cname != NULL) {
+                       free(hname);
+                       hname = cname;
+                       if (innetgr(netgroup, hname, NULL, NULL)) {
+                               match = 1;
+                               goto out;
+                       }
+               }
        }
 
        /* Okay, strip off the domain (if we have one) */
        dot = strchr(hname, '.');
        if (dot == NULL)
-               return 0;
+               goto out;
 
        *dot = '\0';
        match = innetgr(netgroup, hname, NULL, NULL);
-       *dot = '.';
 
+out:
+       free(hname);
        return match;
 }
 #else  /* !HAVE_INNETGR */
@@ -558,10 +592,18 @@ client_check(const nfs_client *clp, const struct addrinfo *ai)
        return 0;
 }
 
+/**
+ * client_gettype - determine type of nfs_client given an identifier
+ * @ident: '\0'-terminated ASCII string containing a client identifier
+ *
+ * Returns the type of nfs_client record that would be used for
+ * this client.
+ */
 int
 client_gettype(char *ident)
 {
-       char    *sp;
+       struct addrinfo *ai;
+       char *sp;
 
        if (ident[0] == '\0' || strcmp(ident, "*")==0)
                return MCL_ANONYMOUS;
@@ -581,12 +623,16 @@ client_gettype(char *ident)
                if (*sp == '\\' && sp[1])
                        sp++;
        }
-       /* check for N.N.N.N */
-       sp = ident;
-       if(!isdigit(*sp) || strtoul(sp, &sp, 10) > 255 || *sp != '.') return MCL_FQDN;
-       sp++; if(!isdigit(*sp) || strtoul(sp, &sp, 10) > 255 || *sp != '.') return MCL_FQDN;
-       sp++; if(!isdigit(*sp) || strtoul(sp, &sp, 10) > 255 || *sp != '.') return MCL_FQDN;
-       sp++; if(!isdigit(*sp) || strtoul(sp, &sp, 10) > 255 || *sp != '\0') return MCL_FQDN;
-       /* we lie here a bit. but technically N.N.N.N == N.N.N.N/32 :) */
-       return MCL_SUBNETWORK;
+
+       /*
+        * Treat unadorned IP addresses as MCL_SUBNETWORK.
+        * Everything else is MCL_FQDN.
+        */
+       ai = host_pton(ident);
+       if (ai != NULL) {
+               freeaddrinfo(ai);
+               return MCL_SUBNETWORK;
+       }
+
+       return MCL_FQDN;
 }