From b14e6b526baed29762dd8d88de4d59f3bd922ea0 Mon Sep 17 00:00:00 2001
From: Mark Spencer <markster@digium.com>
Date: Sat, 27 Sep 2003 00:22:46 +0000
Subject: [PATCH] update DNS resolver
git-svn-id: https://origsvn.digium.com/svn/asterisk/trunk@1555 65c4cc65-6c06-0410-ace0-fbb531ad65f3
---
Makefile | 2 +-
enum.c | 223 ++++++++++---------------------------------------------
srv.c | 217 ++++++++---------------------------------------------
3 files changed, 72 insertions(+), 370 deletions(-)
diff --git a/Makefile b/Makefile
index 3281d2b178..616f1d2120 100755
--- a/Makefile
+++ b/Makefile
@@ -137,7 +137,7 @@ OBJS=io.o sched.o logger.o frame.o loader.o config.o channel.o \
ulaw.o alaw.o callerid.o fskmodem.o image.o app.o \
cdr.o tdd.o acl.o rtp.o manager.o asterisk.o ast_expr.o \
dsp.o chanvars.o indications.o autoservice.o db.o privacy.o \
- astmm.o enum.o srv.o
+ astmm.o enum.o srv.o dns.o
CC=gcc
INSTALL=install
diff --git a/enum.c b/enum.c
index ef6c19b504..601754d9ed 100755
--- a/enum.c
+++ b/enum.c
@@ -11,67 +11,27 @@
*
*/
-#include <string.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <stdlib.h>
#include <sys/types.h>
#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
-#include <errno.h>
+#include <stdlib.h>
+#include <string.h>
#include <ctype.h>
#include <regex.h>
-
+#include <unistd.h>
+#include <errno.h>
#include <asterisk/logger.h>
#include <asterisk/options.h>
#include <asterisk/enum.h>
+#include <asterisk/dns.h>
#include <asterisk/channel.h>
#include <asterisk/config.h>
-#define MAX_SIZE 4096
-
#define TOPLEV "e164.arpa."
-typedef struct {
- unsigned id :16; /* query identification number */
-#if BYTE_ORDER == BIG_ENDIAN
- /* fields in third byte */
- unsigned qr: 1; /* response flag */
- unsigned opcode: 4; /* purpose of message */
- unsigned aa: 1; /* authoritive answer */
- unsigned tc: 1; /* truncated message */
- unsigned rd: 1; /* recursion desired */
- /* fields in fourth byte */
- unsigned ra: 1; /* recursion available */
- unsigned unused :1; /* unused bits (MBZ as of 4.9.3a3) */
- unsigned ad: 1; /* authentic data from named */
- unsigned cd: 1; /* checking disabled by resolver */
- unsigned rcode :4; /* response code */
-#endif
-#if BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
- /* fields in third byte */
- unsigned rd :1; /* recursion desired */
- unsigned tc :1; /* truncated message */
- unsigned aa :1; /* authoritive answer */
- unsigned opcode :4; /* purpose of message */
- unsigned qr :1; /* response flag */
- /* fields in fourth byte */
- unsigned rcode :4; /* response code */
- unsigned cd: 1; /* checking disabled by resolver */
- unsigned ad: 1; /* authentic data from named */
- unsigned unused :1; /* unused bits (MBZ as of 4.9.3a3) */
- unsigned ra :1; /* recursion available */
-#endif
- /* remaining bytes */
- unsigned qdcount :16; /* number of question entries */
- unsigned ancount :16; /* number of answer entries */
- unsigned nscount :16; /* number of authority entries */
- unsigned arcount :16; /* number of resource entries */
-} dns_HEADER;
-
static struct enum_search {
char toplev[80];
struct enum_search *next;
@@ -81,36 +41,6 @@ static int enumver = 0;
static ast_mutex_t enumlock = AST_MUTEX_INITIALIZER;
-static int skip_name(unsigned char *s, int len)
-{
- /* Shamelessly take from SER */
- int x = 0;
- while(x < len) {
- if (!*s) {
- s++;
- x++;
- break;
- }
- if (((*s) & 0xc0) == 0xc0) {
- s += 2;
- x += 2;
- break;
- }
- x += *s + 1;
- s += *s + 1;
- }
- if (x >= len)
- return -1;
- return x;
-}
-
-struct dn_answer {
- unsigned short rtype;
- unsigned short class;
- unsigned int ttl;
- unsigned short size;
-} __attribute__ ((__packed__));
-
struct naptr {
unsigned short order;
unsigned short pref;
@@ -171,13 +101,8 @@ static int parse_naptr(unsigned char *dst, int dstsize, char *tech, int techsize
return -1;
}
-#if 0
- printf("Input: %s\n", naptrinput);
- printf("Flags: %s\n", flags);
- printf("Services: %s\n", services);
- printf("Regexp: %s\n", regexp);
- printf("Repl: %s\n", repl);
-#endif
+ ast_log(LOG_DEBUG, "input='%s', flags='%s', services='%s', regexp='%s', repl='%s'\n",
+ naptrinput, flags, services, regexp, repl);
if (tolower(flags[0]) != 'u') {
ast_log(LOG_WARNING, "Flag must be 'U' or 'u'.\n");
@@ -283,119 +208,56 @@ static int parse_naptr(unsigned char *dst, int dstsize, char *tech, int techsize
return 0;
}
-static int parse_answer(unsigned char *dst, int dstlen, unsigned char *tech, int techlen, unsigned char *answer, int len, char *naptrinput)
+struct enum_context {
+ char *dst;
+ int dstlen;
+ char *tech;
+ int techlen;
+ char *naptrinput;
+};
+
+static int enum_callback(void *context, u_char *answer, int len, u_char *fullanswer)
{
- /*
- * This function is influenced by "ser" the SIP router.
- */
- int x;
- int res;
- dns_HEADER *h;
- struct dn_answer *ans;
- dst[0] = '\0';
- tech[0] = '\0';
-#if 0
- for (x=0;x<len;x++) {
- if ((answer[x] < 32) || (answer[x] > 127)) {
- if (lastlit)
- printf("\"");
- printf(" 0x%02x", answer[x]);
- lastlit = 0;
- } else {
- if (!lastlit)
- printf(" \"");
- printf("%c", answer[x]);
- lastlit = 1;
- }
- }
- printf("\n");
-#endif
- h = (dns_HEADER *)answer;
- /* Skip over DNS header */
- answer += sizeof(dns_HEADER);
- len -= sizeof(dns_HEADER);
-#if 0
- printf("Query count: %d\n", ntohs(h->qdcount));
-#endif
- for (x=0;x<ntohs(h->qdcount);x++) {
- if ((res = skip_name(answer, len)) < 0) {
- ast_log(LOG_WARNING, "Couldn't skip over name\n");
- return -1;
- }
- answer += res;
- len -= res;
- answer += 4; /* Skip QCODE / QCLASS */
- len -= 4;
- if (len < 0) {
- ast_log(LOG_WARNING, "Strange query size\n");
- return -1;
- }
- }
-#if 0
- printf("Length remaining: %d\n", len);
- printf("Answer count: %d\n", ntohs(h->ancount));
- printf("Looking for %d/%d\n", C_IN, T_NAPTR);
-#endif
- for (x=0;x<ntohs(h->ancount);x++) {
- if ((res = skip_name(answer, len)) < 0) {
- ast_log(LOG_WARNING, "Failed to skip name :(\n");
- return -1;
- }
- answer += res;
- len -= res;
- ans = (struct dn_answer *)answer;
- answer += sizeof(struct dn_answer);
- len -= sizeof(struct dn_answer);
- if (len < 0)
- return -1;
-#if 0
- printf("Type: %d, class: %d, ttl: %d, length: %d\n", ntohs(ans->rtype), ntohs(ans->class),
- ntohl(ans->ttl), ntohs(ans->size));
-#endif
- len -= ntohs(ans->size);
- if (len < 0) {
- ast_log(LOG_WARNING, "Length exceeds frame\n");
- return -1;
- }
- if ((ntohs(ans->class) == C_IN) && (ntohs(ans->rtype) == T_NAPTR)) {
- if (parse_naptr(dst, dstlen, tech, techlen, answer, ntohs(ans->size), naptrinput))
- ast_log(LOG_WARNING, "Failed to parse naptr :(\n");
- if (strlen(dst))
- return 0;
- }
- answer += ntohs(ans->size);
- }
+ struct enum_context *c = (struct enum_context *)context;
+
+ if (parse_naptr(c->dst, c->dstlen, c->tech, c->techlen, answer, len, c->naptrinput))
+ ast_log(LOG_WARNING, "Failed to parse naptr :(\n");
+
+ if (strlen(c->dst))
+ return 1;
+
return 0;
}
int ast_get_enum(struct ast_channel *chan, const char *number, char *dst, int dstlen, char *tech, int techlen)
{
- unsigned char answer[MAX_SIZE];
+ struct enum_context context;
char tmp[259 + 80];
char naptrinput[80] = "+";
int pos = strlen(number) - 1;
- int newpos=0;
- int res = -1;
+ int newpos = 0;
int ret = -1;
struct enum_search *s = NULL;
int version = -1;
- struct __res_state enumstate;
- res_ninit(&enumstate);
- if (chan && ast_autoservice_start(chan) < 0)
- return -1;
strncat(naptrinput, number, sizeof(naptrinput) - 2);
+ context.naptrinput = naptrinput;
+ context.dst = dst;
+ context.dstlen = dstlen;
+ context.tech = tech;
+ context.techlen = techlen;
+
if (pos > 128)
pos = 128;
while(pos >= 0) {
tmp[newpos++] = number[pos--];
tmp[newpos++] = '.';
}
-#if 0
- printf("Looking for '%s'\n", tmp);
-#endif
+ if (chan && ast_autoservice_start(chan) < 0)
+ return -1;
+
for(;;) {
ast_mutex_lock(&enumlock);
if (version != enumver) {
@@ -411,25 +273,16 @@ int ast_get_enum(struct ast_channel *chan, const char *number, char *dst, int ds
ast_mutex_unlock(&enumlock);
if (!s)
break;
- res = res_nsearch(&enumstate, tmp, C_IN, T_NAPTR, answer, sizeof(answer));
- if (res > 0)
+ ret = ast_search_dns(&context, tmp, C_IN, T_NAPTR, enum_callback);
+ if (ret > 0)
break;
}
- if (res > 0) {
- if ((res = parse_answer(dst, dstlen, tech, techlen, answer, res, naptrinput))) {
- ast_log(LOG_WARNING, "Parse error returned %d\n", res);
- ret = 0;
- } else {
- ast_log(LOG_DEBUG, "Found technology '%s', destination '%s'\n", tech, dst);
- ret = 1;
- }
- } else {
+ if (ret < 0) {
ast_log(LOG_DEBUG, "No such number found: %s (%s)\n", tmp, strerror(errno));
ret = 0;
}
if (chan)
ret |= ast_autoservice_stop(chan);
- res_nclose(&enumstate);
return ret;
}
diff --git a/srv.c b/srv.c
index c6365e361c..25011ad52f 100755
--- a/srv.c
+++ b/srv.c
@@ -11,68 +11,19 @@
*
*/
-#include <string.h>
-#include <fcntl.h>
-#include <unistd.h>
-#include <stdlib.h>
#include <sys/types.h>
-#include <sys/socket.h>
#include <netinet/in.h>
#include <arpa/nameser.h>
#include <resolv.h>
-#include <errno.h>
+#include <stdio.h>
+#include <string.h>
+#include <unistd.h>
+#include <asterisk/channel.h>
#include <asterisk/logger.h>
-#include <asterisk/options.h>
#include <asterisk/srv.h>
-#include <asterisk/channel.h>
-#include <asterisk/config.h>
-
-#define MAX_SIZE 4096
-
-typedef struct {
- unsigned id :16; /* query identification number */
-#if BYTE_ORDER == BIG_ENDIAN
- /* fields in third byte */
- unsigned qr: 1; /* response flag */
- unsigned opcode: 4; /* purpose of message */
- unsigned aa: 1; /* authoritive answer */
- unsigned tc: 1; /* truncated message */
- unsigned rd: 1; /* recursion desired */
- /* fields in fourth byte */
- unsigned ra: 1; /* recursion available */
- unsigned unused :1; /* unused bits (MBZ as of 4.9.3a3) */
- unsigned ad: 1; /* authentic data from named */
- unsigned cd: 1; /* checking disabled by resolver */
- unsigned rcode :4; /* response code */
-#endif
-#if BYTE_ORDER == LITTLE_ENDIAN || BYTE_ORDER == PDP_ENDIAN
- /* fields in third byte */
- unsigned rd :1; /* recursion desired */
- unsigned tc :1; /* truncated message */
- unsigned aa :1; /* authoritive answer */
- unsigned opcode :4; /* purpose of message */
- unsigned qr :1; /* response flag */
- /* fields in fourth byte */
- unsigned rcode :4; /* response code */
- unsigned cd: 1; /* checking disabled by resolver */
- unsigned ad: 1; /* authentic data from named */
- unsigned unused :1; /* unused bits (MBZ as of 4.9.3a3) */
- unsigned ra :1; /* recursion available */
-#endif
- /* remaining bytes */
- unsigned qdcount :16; /* number of question entries */
- unsigned ancount :16; /* number of answer entries */
- unsigned nscount :16; /* number of authority entries */
- unsigned arcount :16; /* number of resource entries */
-} dns_HEADER;
-
-struct dn_answer {
- unsigned short rtype;
- unsigned short class;
- unsigned int ttl;
- unsigned short size;
-} __attribute__ ((__packed__));
+#include <asterisk/dns.h>
+#include <asterisk/options.h>
struct srv {
unsigned short priority;
@@ -80,29 +31,6 @@ struct srv {
unsigned short portnum;
} __attribute__ ((__packed__));
-static int skip_name(unsigned char *s, int len)
-{
- /* Shamelessly take from SER */
- int x = 0;
- while(x < len) {
- if (!*s) {
- s++;
- x++;
- break;
- }
- if (((*s) & 0xc0) == 0xc0) {
- s += 2;
- x += 2;
- break;
- }
- x += *s + 1;
- s += *s + 1;
- }
- if (x >= len)
- return -1;
- return x;
-}
-
static int parse_ie(unsigned char *data, int maxdatalen, unsigned char *src, int srclen)
{
int len, olen;
@@ -149,124 +77,45 @@ static int parse_srv(unsigned char *host, int hostlen, int *portno, unsigned cha
return(-1);
}
-static int parse_answer(unsigned char *host, int hostlen, int *port, char *answer, int len)
+struct srv_context {
+ char *host;
+ int hostlen;
+ int *port;
+};
+
+static int srv_callback(void *context, u_char *answer, int len, u_char *fullanswer)
{
- /*
- * This function is influenced by "ser" the SIP router.
- */
- int x;
- int res;
- dns_HEADER *h;
- struct dn_answer *ans;
-/* int lastlit = 1; */
- char *oanswer = answer;
- host[0] = '\0';
- *port = 0;
+ struct srv_context *c = (struct srv_context *)context;
-#if 0
- for (x=0;x<len;x++) {
- if ((answer[x] < 32) || (answer[x] > 127)) {
- if (lastlit)
- printf("\"");
- printf(" 0x%02x", answer[x]);
- lastlit = 0;
- } else {
- if (!lastlit)
- printf(" \"");
- printf("%c", answer[x]);
- lastlit = 1;
- }
- }
- printf("\n");
-#endif
- h = (dns_HEADER *)answer;
- /* Skip over DNS header */
- answer += sizeof(dns_HEADER);
- len -= sizeof(dns_HEADER);
-#if 0
- printf("Query count: %d\n", ntohs(h->qdcount));
-#endif
- for (x=0;x<ntohs(h->qdcount);x++) {
- if ((res = skip_name(answer, len)) < 0) {
- ast_log(LOG_WARNING, "Couldn't skip over name\n");
- return -1;
- }
- answer += res;
- len -= res;
- answer += 4; /* Skip QCODE / QCLASS */
- len -= 4;
- if (len < 0) {
- ast_log(LOG_WARNING, "Strange query size\n");
- return -1;
- }
- }
-#if 0
- printf("Length remaining: %d, already at %04x\n", len, 0x2a + (answer - oanswer));
- printf("Answer count: %d\n", ntohs(h->ancount));
- printf("Looking for %d/%d\n", C_IN, T_SRV);
- printf("Answer so far: %02x %02x %02x %02x %02x %02x\n", answer[0], answer[1], answer[2], answer[3], answer[4], answer[5]);
-#endif
- for (x=0;x<ntohs(h->ancount);x++) {
- if ((res = skip_name(answer, len)) < 0) {
- ast_log(LOG_WARNING, "Failed to skip name :(\n");
- return -1;
- }
- answer += res;
- len -= res;
- ans = (struct dn_answer *)answer;
- answer += sizeof(struct dn_answer);
- len -= sizeof(struct dn_answer);
- if (len < 0)
- return -1;
-#if 0
- printf("Type: %d (%04x), class: %d (%04x), ttl: %d (%08x), length: %d (%04x)\n", ntohs(ans->rtype), ntohs(ans->rtype), ntohs(ans->class), ntohs(ans->class),
- ntohl(ans->ttl), ntohl(ans->ttl), ntohs(ans->size), ntohs(ans->size));
-#endif
- len -= ntohs(ans->size);
- if (len < 0) {
- ast_log(LOG_WARNING, "Length exceeds frame by %d\n", -len);
- return -1;
- }
- if ((ntohs(ans->class) == C_IN) && (ntohs(ans->rtype) == T_SRV)) {
+ if (parse_srv(c->host, c->hostlen, c->port, answer, len, fullanswer))
+ ast_log(LOG_WARNING, "Failed to parse srv\n");
- if (parse_srv(host, hostlen, port, answer, ntohs(ans->size),oanswer))
- ast_log(LOG_WARNING, "Failed to parse srv :(\n");
+ if (strlen(c->host))
+ return 1;
- if (strlen(host))
- return 0;
- }
- answer += ntohs(ans->size);
- }
- return 0;
+ return 0;
}
int ast_get_srv(struct ast_channel *chan, char *host, int hostlen, int *port, const char *service)
{
- int res;
- int ret = -1;
- struct __res_state srvstate;
- char answer[MAX_SIZE];
+ struct srv_context context;
+ int ret;
+
+ context.host = host;
+ context.hostlen = hostlen;
+ context.port = port;
- if (*port)
- *port = 0;
- res_ninit(&srvstate);
if (chan && ast_autoservice_start(chan) < 0)
return -1;
- res = res_nsearch(&srvstate, service, C_IN, T_SRV, answer, sizeof(answer));
- if (res > 0) {
- if ((res = parse_answer(host, hostlen, port, answer, res))) {
- ast_log(LOG_WARNING, "Parse error returned %d\n", res);
- ret = 0;
- } else {
- ast_log(LOG_DEBUG, "Found host '%s', port '%d'\n", host, *port);
- ret = 1;
- }
- } else {
- ast_log(LOG_DEBUG, "No such service found: %s (%s)\n", service, strerror(errno));
- ret = 0;
- }
+
+ ret = ast_search_dns(&context, service, C_IN, T_SRV, srv_callback);
+
if (chan)
ret |= ast_autoservice_stop(chan);
- res_nclose(&srvstate);
+
+ if (ret <= 0)
+ return ret;
+ strcpy(host, "");
+ *port = -1;
return ret;
}
--
GitLab