test_s2.c

Sofia SIP is an open-source SIP User-Agent library, compliant with the IETF RFC3261 specification.

  FLAGS_OPCODE = (15 << 11),	/* mask */
  FLAGS_AA = (1 << 10),		/*  */
  FLAGS_TC = (1 << 9),
  FLAGS_RD = (1 << 8),
  FLAGS_RA = (1 << 7),

  FLAGS_RCODE = (15 << 0),	/* mask of return code */

  FLAGS_OK = 0,			/* No error condition. */
  FLAGS_FORMAT_ERR = 1,		/* Server could not interpret query. */
  FLAGS_SERVER_ERR = 2,		/* Server error. */
  FLAGS_NAME_ERR = 3,		/* No domain name. */
  FLAGS_UNIMPL_ERR = 4,		/* Not implemented. */
  FLAGS_AUTH_ERR = 5,		/* Refused */
};

uint32_t s2_dns_ttl = 3600;

static int
s2_dns_query(struct tester *s2,
	     su_wait_t *w,
	     su_wakeup_arg_t *arg)
{
  union {
    struct m_header header[1];
    uint8_t buffer[1500];
  } request;
  ssize_t len;

  su_socket_t socket;
  su_sockaddr_t su[1];
  socklen_t sulen = sizeof su;
  uint16_t flags;
  struct s2_dns_response *r;
  size_t const hlen = sizeof r->header;

  (void)arg;

  socket = s2->dns.socket;

  len = su_recvfrom(socket, request.buffer, sizeof request.buffer, 0,
		    &su->su_sa, &sulen);

  flags = ntohs(request.header->mh_flags);

  if (len < (ssize_t)hlen)
    return 0;
  if ((flags & FLAGS_QR) == FLAGS_QR)
    return 0;
  if ((flags & FLAGS_RCODE) != FLAGS_OK)
    return 0;

  if ((flags & FLAGS_OPCODE) != FLAGS_QUERY
      || ntohs(request.header->mh_qdcount) != 1) {
    flags |= FLAGS_QR | FLAGS_UNIMPL_ERR;
    request.header->mh_flags = htons(flags);
    su_sendto(socket, request.buffer, len, 0, &su->su_sa, sulen);
    return 0;
  }

  for (r = zonedata; r; r = r->next) {
    if (memcmp(r->data, request.buffer + hlen, r->qlen) == 0)
      break;
  }

  if (r) {
    flags |= FLAGS_QR | FLAGS_AA | FLAGS_OK;
    request.header->mh_flags = htons(flags);
    request.header->mh_ancount = htons(r->header->mh_ancount);
    request.header->mh_nscount = htons(r->header->mh_nscount);
    request.header->mh_arcount = htons(r->header->mh_arcount);
    memcpy(request.buffer + hlen + r->qlen,
	   r->data + r->qlen,
	   r->dlen - r->qlen);
    len = hlen + r->dlen;
  }
  else {
    flags |= FLAGS_QR | FLAGS_AA | FLAGS_NAME_ERR;
  }

  request.header->mh_flags = htons(flags);
  su_sendto(socket, request.buffer, len, 0, &su->su_sa, sulen);
  return 0;
}

static void put_uint16(struct s2_dns_response *m, uint16_t h)
{
  uint8_t *p = m->data + m->dlen;

  assert(m->dlen + (sizeof h) < sizeof m->data);
  p[0] = h >> 8; p[1] = h;
  m->dlen += (sizeof h);
}

static void put_uint32(struct s2_dns_response *m, uint32_t w)
{
  uint8_t *p = m->data + m->dlen;

  assert(m->dlen + (sizeof w) < sizeof m->data);
  p[0] = w >> 24; p[1] = w >> 16; p[2] = w >> 8; p[3] = w;
  m->dlen += (sizeof w);
}

static void put_domain(struct s2_dns_response *m, char const *domain)
{
  char const *label;
  size_t llen;

  /* Copy domain into query label at a time */
  for (label = domain; label && label[0]; label += llen) {
    assert(!(label[0] == '.' && label[1] != '\0'));
    llen = strcspn(label, ".");
    assert(llen < 64);
    assert(m->dlen + llen + 1 < sizeof m->data);
    m->data[m->dlen++] = (uint8_t)llen;
    if (llen == 0)
      return;

    memcpy(m->data + m->dlen, label, llen);
    m->dlen += (uint16_t)llen;

    if (label[llen] == '\0')
      break;
    if (label[llen + 1])
      llen++;
  }

  assert(m->dlen < sizeof m->data);
  m->data[m->dlen++] = '\0';
}

static void put_string(struct s2_dns_response *m, char const *string)
{
  uint8_t *p = m->data + m->dlen;
  size_t len = strlen(string);

  assert(len <= 255);
  assert(m->dlen + len + 1 < sizeof m->data);

  *p++ = (uint8_t)len;
  memcpy(p, string, len);
  m->dlen += len + 1;
}

static uint16_t put_len_at(struct s2_dns_response *m)
{
  uint16_t at = m->dlen;
  assert(m->dlen + sizeof(at) < sizeof m->data);
  memset(m->data + m->dlen, 0, sizeof(at));
  m->dlen += sizeof(at);
  return at;
}

static void put_len(struct s2_dns_response *m, uint16_t start)
{
  uint8_t *p = m->data + start;
  uint16_t len = m->dlen - (start + 2);
  p[0] = len >> 8; p[1] = len;
}

static void put_data(struct s2_dns_response *m, void *data, uint16_t len)
{
  assert(m->dlen + len < sizeof m->data);
  memcpy(m->data + m->dlen, data, len);
  m->dlen += len;
}

static void put_query(struct s2_dns_response *m, char const *domain,
		      uint16_t qtype)
{
  assert(m->header->mh_qdcount == 0);
  put_domain(m, domain), put_uint16(m, qtype), put_uint16(m, sres_class_in);
  m->header->mh_qdcount++;
  m->qlen = m->dlen;
}

static void put_a_record(struct s2_dns_response *m,
			 char const *domain,
			 struct in_addr addr)
{
  uint16_t start;

  put_domain(m, domain);
  put_uint16(m, sres_type_a);
  put_uint16(m, sres_class_in);
  put_uint32(m, s2_dns_ttl);
  start = put_len_at(m);

  put_data(m, &addr, sizeof addr);
  put_len(m, start);
}

static void put_srv_record(struct s2_dns_response *m,
			   char const *domain,
			   uint16_t prio, uint16_t weight,
			   uint16_t port, char const *target)
{
  uint16_t start;
  put_domain(m, domain);
  put_uint16(m, sres_type_srv);
  put_uint16(m, sres_class_in);
  put_uint32(m, s2_dns_ttl);
  start = put_len_at(m);

  put_uint16(m, prio);
  put_uint16(m, weight);
  put_uint16(m, port);
  put_domain(m, target);
  put_len(m, start);
}

static void put_naptr_record(struct s2_dns_response *m,
			     char const *domain,
			     uint16_t order, uint16_t preference,
			     char const *flags,
			     char const *services,
			     char const *regexp,
			     char const *replace)
{
  uint16_t start;
  put_domain(m, domain);
  put_uint16(m, sres_type_naptr);
  put_uint16(m, sres_class_in);
  put_uint32(m, s2_dns_ttl);
  start = put_len_at(m);

  put_uint16(m, order);
  put_uint16(m, preference);
  put_string(m, flags);
  put_string(m, services);
  put_string(m, regexp);
  put_domain(m, replace);
  put_len(m, start);
}

static void put_srv_record_from_uri(struct s2_dns_response *m,
				    char const *base,
				    uint16_t prio, uint16_t weight,
				    url_t const *uri, char const *server)
{
  char domain[1024] = "none";
  char const *service = url_port(uri);
  uint16_t port;

  if (uri->url_type == url_sips) {
    strcpy(domain, "_sips._tcp.");
  }
  else if (uri->url_type == url_sip) {
    if (url_has_param(uri, "transport=udp")) {
      strcpy(domain, "_sip._udp.");
    }
    else if (url_has_param(uri, "transport=tcp")) {
      strcpy(domain, "_sip._tcp.");
    }
  }

  assert(strcmp(domain, "none"));

  strcat(domain, base);

  if (m->header->mh_qdcount == 0)
    put_query(m, domain, sres_type_srv);

  port = (uint16_t)strtoul(service, NULL, 10);

  put_srv_record(m, domain, prio, weight, port, server);
}

static
void s2_add_to_zone(struct s2_dns_response *_r)
{
  size_t size = offsetof(struct s2_dns_response, data[_r->dlen]);
  struct s2_dns_response *r = malloc(size); assert(r);

  memcpy(r, _r, size);
  r->next = zonedata;
  zonedata = r;
}


static void make_server(char *server, char const *prefix, char const *domain)
{
  strcpy(server, prefix);

  if (strlen(server) == 0 || server[strlen(server) - 1] != '.') {
    strcat(server, ".");
    strcat(server, domain);
  }
}

/** Set up DNS domain */
void s2_dns_domain(char const *domain, int use_naptr,
		   /* char *prefix, int priority, url_t const *uri, */
		   ...)
{
  struct s2_dns_response m[1];

  char server[1024], target[1024];

  va_list va0, va;
  char const *prefix; int priority; url_t const *uri;
  struct in_addr localhost;

  assert(s2->dns.reg != 0);

  su_inet_pton(AF_INET, "127.0.0.1", &localhost);

  va_start(va0, use_naptr);

  if (use_naptr) {
    memset(m, 0, sizeof m);
    put_query(m, domain, sres_type_naptr);

    va_copy(va, va0);

    for (;(prefix = va_arg(va, char *));) {
      char *services = NULL;

      priority = va_arg(va, int);
      uri = va_arg(va, url_t *); assert(uri);

      if (uri->url_type == url_sips) {
	services = "SIPS+D2T";
	strcpy(target, "_sips._tcp.");
      }
      else if (uri->url_type == url_sip) {
	if (url_has_param(uri, "transport=udp")) {
	  services = "SIP+D2U";
	  strcpy(target, "_sip._udp.");
	}
	else if (url_has_param(uri, "transport=tcp")) {
	  services = "SIP+D2T";
	  strcpy(target, "_sip._tcp.");
	}
      }

      strcat(target, domain);
      assert(services);
      put_naptr_record(m, domain, 1, priority, "s", services, "", target);
      m->header->mh_ancount++;
    }

    va_end(va);
    va_copy(va, va0);

    for (;(prefix = va_arg(va, char *));) {
      priority = va_arg(va, int);
      uri = va_arg(va, url_t *); assert(uri);

      make_server(server, prefix, domain);

      put_srv_record_from_uri(m, domain, priority, 10, uri, server);
      m->header->mh_arcount++;

      put_a_record(m, server, localhost);
      m->header->mh_arcount++;
    }
    va_end(va);

    s2_add_to_zone(m);
  }

  /* Add SRV records */
  va_copy(va, va0);
  for (;(prefix = va_arg(va, char *));) {
    priority = va_arg(va, int);
    uri = va_arg(va, url_t *); assert(uri);

    make_server(server, prefix, domain);

    memset(m, 0, sizeof m);
    put_srv_record_from_uri(m, domain, priority, 10, uri, server);
    m->header->mh_ancount++;

    strcpy(server, prefix); strcat(server, domain);

    put_a_record(m, server, localhost);
    m->header->mh_arcount++;

    s2_add_to_zone(m);
  }
  va_end(va);

  /* Add A records */
  va_copy(va, va0);
  for (;(prefix = va_arg(va, char *));) {
    (void)va_arg(va, int);
    (void)va_arg(va, url_t *);

    memset(m, 0, sizeof m);
    make_server(server, prefix, domain);

    put_query(m, server, sres_type_a);
    put_a_record(m, server, localhost);
    m->header->mh_ancount++;

    s2_add_to_zone(m);
  }
  va_end(va);

  va_end(va0);
}

void
s2_teardown(void)
{
  s2 = NULL;
  su_deinit();
}

/* ====================================================================== */

#include <sofia-sip/sresolv.h>

nua_t *s2_nua_setup(tag_type_t tag, tag_value_t value, ...)
{
  ta_list ta;

  s2_setup_base(NULL);
  s2_setup_dns();

  s2_setup_logs(0);
  s2_setup_tport(NULL, TPTAG_LOG(0), TAG_END());
  assert(s2->contact);

  s2_dns_domain("example.org", 1,
		"s2", 1, s2->udp.contact->m_url,
		"s2", 1, s2->tcp.contact->m_url,
		NULL);

  ta_start(ta, tag, value);
  s2->nua = 
    nua_create(s2->root,
	       s2_nua_callback,
	       s2,
	       SIPTAG_FROM_STR("Alice <sip:[e-mail]>"),
	       /* NUTAG_PROXY((url_string_t *)s2->contact->m_url), */
	       /* Use internal DNS server */
	       NUTAG_PROXY("sip:example.org"),
#if HAVE_WIN32
	       SRESTAG_RESOLV_CONF("NUL"),
#else
	       SRESTAG_RESOLV_CONF("/dev/null"),
#endif
	       ta_tags(ta));
  ta_end(ta);
  
  return s2->nua;
}

void s2_nua_teardown(void)
{
  nua_destroy(s2->nua);
  s2->nua = NULL;
  s2_teardown();
}

/* ====================================================================== */

/** Register NUA user.
 *
 * <pre>
 *  A                  B
 *  |-----REGISTER---->|
 *  |<-----200 OK------|
 *  |                  |
 * </pre>
 */
void s2_register_setup(void)
{
  nua_handle_t *nh;
  struct message *m;

  assert(s2 && s2->nua);
  assert(!s2->registration->nh);

  nh = nua_handle(s2->nua, NULL, TAG_END());

  nua_register(nh, TAG_END());

  m = s2_wait_for_request(SIP_METHOD_REGISTER);
  assert(m);
  s2_save_register(m);

  s2_respond_to(m, NULL,
		SIP_200_OK,
		SIPTAG_CONTACT(s2->registration->contact),
		TAG_END());
  s2_free_message(m);

  assert(s2->registration->contact != NULL);
  s2_check_event(nua_r_register, 200);

  s2->registration->nh = nh;
}

/** Un-register NUA user.
 *
 * <pre>
 *  A                  B
 *  |-----REGISTER---->|
 *  |<-----200 OK------|
 *  |                  |
 * </pre>
 */
void s2_register_teardown(void)
{
  if (s2 && s2->registration->nh) {
    nua_handle_t *nh = s2->registration->nh;
    struct message *m;

    nua_unregister(nh, TAG_END());
    
    m = s2_wait_for_request(SIP_METHOD_REGISTER); assert(m);
    s2_save_register(m);
    s2_respond_to(m, NULL,
		  SIP_200_OK,
		  SIPTAG_CONTACT(s2->registration->contact),
		  TAG_END());
    assert(s2->registration->contact == NULL);

    s2_free_message(m);

    s2_check_event(nua_r_unregister, 200);

    nua_handle_destroy(nh);
    s2->registration->nh = NULL;
  }
}