Adding upstream version 3.4.23.upstream/3.4.23upstream

Signed-off-by: Daniel Baumann <daniel.baumann@progress-linux.org>

1 files changed, 347 insertions, 0 deletions

diff --git a/src/dns/dns_rr.c b/src/dns/dns_rr.c
new file mode 100644
index 0000000..b550788
--- /dev/null
+++ b/src/dns/dns_rr.c
@@ -0,0 +1,347 @@
+/*++
+/* NAME
+/*	dns_rr 3
+/* SUMMARY
+/*	resource record memory and list management
+/* SYNOPSIS
+/*	#include <dns.h>
+/*
+/*	DNS_RR	*dns_rr_create(qname, rname, type, class, ttl, preference,
+/*				data, data_len)
+/*	const char *qname;
+/*	const char *rname;
+/*	unsigned short type;
+/*	unsigned short class;
+/*	unsigned int ttl;
+/*	unsigned preference;
+/*	const char *data;
+/*	size_t data_len;
+/*
+/*	void	dns_rr_free(list)
+/*	DNS_RR	*list;
+/*
+/*	DNS_RR	*dns_rr_copy(record)
+/*	DNS_RR	*record;
+/*
+/*	DNS_RR	*dns_rr_append(list, record)
+/*	DNS_RR	*list;
+/*	DNS_RR	*record;
+/*
+/*	DNS_RR	*dns_rr_sort(list, compar)
+/*	DNS_RR	*list
+/*	int	(*compar)(DNS_RR *, DNS_RR *);
+/*
+/*	int	dns_rr_compare_pref_ipv6(DNS_RR *a, DNS_RR *b)
+/*	DNS_RR	*list
+/*	DNS_RR	*list
+/*
+/*	int	dns_rr_compare_pref_ipv4(DNS_RR *a, DNS_RR *b)
+/*	DNS_RR	*list
+/*	DNS_RR	*list
+/*
+/*	int	dns_rr_compare_pref_any(DNS_RR *a, DNS_RR *b)
+/*	DNS_RR	*list
+/*	DNS_RR	*list
+/*
+/*	DNS_RR	*dns_rr_shuffle(list)
+/*	DNS_RR	*list;
+/*
+/*	DNS_RR	*dns_rr_remove(list, record)
+/*	DNS_RR	*list;
+/*	DNS_RR	*record;
+/* DESCRIPTION
+/*	The routines in this module maintain memory for DNS resource record
+/*	information, and maintain lists of DNS resource records.
+/*
+/*	dns_rr_create() creates and initializes one resource record.
+/*	The \fIqname\fR field specifies the query name.
+/*	The \fIrname\fR field specifies the reply name.
+/*	\fIpreference\fR is used for MX records; \fIdata\fR is a null
+/*	pointer or specifies optional resource-specific data;
+/*	\fIdata_len\fR is the amount of resource-specific data.
+/*
+/*	dns_rr_free() releases the resource used by of zero or more
+/*	resource records.
+/*
+/*	dns_rr_copy() makes a copy of a resource record.
+/*
+/*	dns_rr_append() appends a resource record to a (list of) resource
+/*	record(s).
+/*	A null input list is explicitly allowed.
+/*
+/*	dns_rr_sort() sorts a list of resource records into ascending
+/*	order according to a user-specified criterion. The result is the
+/*	sorted list.
+/*
+/*	dns_rr_compare_pref_XXX() are dns_rr_sort() helpers to sort
+/*	records by their MX preference and by their address family.
+/*
+/*	dns_rr_shuffle() randomly permutes a list of resource records.
+/*
+/*	dns_rr_remove() removes the specified record from the specified list.
+/*	The updated list is the result value.
+/*	The record MUST be a list member.
+/* LICENSE
+/* .ad
+/* .fi
+/*	The Secure Mailer license must be distributed with this software.
+/* AUTHOR(S)
+/*	Wietse Venema
+/*	IBM T.J. Watson Research
+/*	P.O. Box 704
+/*	Yorktown Heights, NY 10598, USA
+/*--*/
+
+/* System library. */
+
+#include <sys_defs.h>
+#include <string.h>
+#include <stdlib.h>
+
+/* Utility library. */
+
+#include <msg.h>
+#include <mymalloc.h>
+#include <myrand.h>
+
+/* DNS library. */
+
+#include "dns.h"
+
+/* dns_rr_create - fill in resource record structure */
+
+DNS_RR *dns_rr_create(const char *qname, const char *rname,
+		              ushort type, ushort class,
+		              unsigned int ttl, unsigned pref,
+		              const char *data, size_t data_len)
+{
+    DNS_RR *rr;
+
+    rr = (DNS_RR *) mymalloc(sizeof(*rr) + data_len - 1);
+    rr->qname = mystrdup(qname);
+    rr->rname = mystrdup(rname);
+    rr->type = type;
+    rr->class = class;
+    rr->ttl = ttl;
+    rr->dnssec_valid = 0;
+    rr->pref = pref;
+    if (data && data_len > 0)
+	memcpy(rr->data, data, data_len);
+    rr->data_len = data_len;
+    rr->next = 0;
+    return (rr);
+}
+
+/* dns_rr_free - destroy resource record structure */
+
+void    dns_rr_free(DNS_RR *rr)
+{
+    if (rr) {
+	if (rr->next)
+	    dns_rr_free(rr->next);
+	myfree(rr->qname);
+	myfree(rr->rname);
+	myfree((void *) rr);
+    }
+}
+
+/* dns_rr_copy - copy resource record */
+
+DNS_RR *dns_rr_copy(DNS_RR *src)
+{
+    ssize_t len = sizeof(*src) + src->data_len - 1;
+    DNS_RR *dst;
+
+    /*
+     * Combine struct assignment and data copy in one block copy operation.
+     */
+    dst = (DNS_RR *) mymalloc(len);
+    memcpy((void *) dst, (void *) src, len);
+    dst->qname = mystrdup(src->qname);
+    dst->rname = mystrdup(src->rname);
+    dst->next = 0;
+    return (dst);
+}
+
+/* dns_rr_append - append resource record to list */
+
+DNS_RR *dns_rr_append(DNS_RR *list, DNS_RR *rr)
+{
+    if (list == 0) {
+	list = rr;
+    } else {
+	list->next = dns_rr_append(list->next, rr);
+    }
+    return (list);
+}
+
+/* dns_rr_compare_pref_ipv6 - compare records by preference, ipv6 preferred */
+
+int     dns_rr_compare_pref_ipv6(DNS_RR *a, DNS_RR *b)
+{
+    if (a->pref != b->pref)
+	return (a->pref - b->pref);
+#ifdef HAS_IPV6
+    if (a->type == b->type)			/* 200412 */
+	return 0;
+    if (a->type == T_AAAA)
+	return (-1);
+    if (b->type == T_AAAA)
+	return (+1);
+#endif
+    return 0;
+}
+
+/* dns_rr_compare_pref_ipv4 - compare records by preference, ipv4 preferred */
+
+int     dns_rr_compare_pref_ipv4(DNS_RR *a, DNS_RR *b)
+{
+    if (a->pref != b->pref)
+	return (a->pref - b->pref);
+#ifdef HAS_IPV6
+    if (a->type == b->type)
+	return 0;
+    if (a->type == T_AAAA)
+	return (+1);
+    if (b->type == T_AAAA)
+	return (-1);
+#endif
+    return 0;
+}
+
+/* dns_rr_compare_pref_any - compare records by preference, protocol-neutral */
+
+int     dns_rr_compare_pref_any(DNS_RR *a, DNS_RR *b)
+{
+    if (a->pref != b->pref)
+	return (a->pref - b->pref);
+    return 0;
+}
+
+/* dns_rr_compare_pref - binary compatibility helper after name change */
+
+int     dns_rr_compare_pref(DNS_RR *a, DNS_RR *b)
+{
+    return (dns_rr_compare_pref_ipv6(a, b));
+}
+
+/* dns_rr_sort_callback - glue function */
+
+static int (*dns_rr_sort_user) (DNS_RR *, DNS_RR *);
+
+static int dns_rr_sort_callback(const void *a, const void *b)
+{
+    DNS_RR *aa = *(DNS_RR **) a;
+    DNS_RR *bb = *(DNS_RR **) b;
+
+    return (dns_rr_sort_user(aa, bb));
+}
+
+/* dns_rr_sort - sort resource record list */
+
+DNS_RR *dns_rr_sort(DNS_RR *list, int (*compar) (DNS_RR *, DNS_RR *))
+{
+    int     (*saved_user) (DNS_RR *, DNS_RR *);
+    DNS_RR **rr_array;
+    DNS_RR *rr;
+    int     len;
+    int     i;
+
+    /*
+     * Save state and initialize.
+     */
+    saved_user = dns_rr_sort_user;
+    dns_rr_sort_user = compar;
+
+    /*
+     * Build linear array with pointers to each list element.
+     */
+    for (len = 0, rr = list; rr != 0; len++, rr = rr->next)
+	 /* void */ ;
+    rr_array = (DNS_RR **) mymalloc(len * sizeof(*rr_array));
+    for (len = 0, rr = list; rr != 0; len++, rr = rr->next)
+	rr_array[len] = rr;
+
+    /*
+     * Sort by user-specified criterion.
+     */
+    qsort((void *) rr_array, len, sizeof(*rr_array), dns_rr_sort_callback);
+
+    /*
+     * Fix the links.
+     */
+    for (i = 0; i < len - 1; i++)
+	rr_array[i]->next = rr_array[i + 1];
+    rr_array[i]->next = 0;
+    list = rr_array[0];
+
+    /*
+     * Cleanup.
+     */
+    myfree((void *) rr_array);
+    dns_rr_sort_user = saved_user;
+    return (list);
+}
+
+/* dns_rr_shuffle - shuffle resource record list */
+
+DNS_RR *dns_rr_shuffle(DNS_RR *list)
+{
+    DNS_RR **rr_array;
+    DNS_RR *rr;
+    int     len;
+    int     i;
+    int     r;
+
+    /*
+     * Build linear array with pointers to each list element.
+     */
+    for (len = 0, rr = list; rr != 0; len++, rr = rr->next)
+	 /* void */ ;
+    rr_array = (DNS_RR **) mymalloc(len * sizeof(*rr_array));
+    for (len = 0, rr = list; rr != 0; len++, rr = rr->next)
+	rr_array[len] = rr;
+
+    /*
+     * Shuffle resource records. Every element has an equal chance of landing
+     * in slot 0.  After that every remaining element has an equal chance of
+     * landing in slot 1, ...  This is exactly n! states for n! permutations.
+     */
+    for (i = 0; i < len - 1; i++) {
+	r = i + (myrand() % (len - i));		/* Victor&Son */
+	rr = rr_array[i];
+	rr_array[i] = rr_array[r];
+	rr_array[r] = rr;
+    }
+
+    /*
+     * Fix the links.
+     */
+    for (i = 0; i < len - 1; i++)
+	rr_array[i]->next = rr_array[i + 1];
+    rr_array[i]->next = 0;
+    list = rr_array[0];
+
+    /*
+     * Cleanup.
+     */
+    myfree((void *) rr_array);
+    return (list);
+}
+
+/* dns_rr_remove - remove record from list, return new list */
+
+DNS_RR *dns_rr_remove(DNS_RR *list, DNS_RR *record)
+{
+    if (list == 0)
+	msg_panic("dns_rr_remove: record not found");
+
+    if (list == record) {
+	list = record->next;
+	record->next = 0;
+	dns_rr_free(record);
+    } else {
+	list->next = dns_rr_remove(list->next, record);
+    }
+    return (list);
+}