raop: Add BA (Basic) and DA (Digest) HTTP authentication helpers

RAOP authentication is using standard HTTP challenge-response authentication
scheme. This patch adds two helper functions that generate the proper hash
(for both techniques) given a username, a password and session related tokens.
This commit is contained in:
Martin Blanchard 2016-11-06 12:54:06 -06:00 committed by Tanu Kaskinen
parent a33c04c0cc
commit 5ff21c3bdd
6 changed files with 365 additions and 49 deletions

View file

@ -65,6 +65,9 @@
#define VOLUME_MIN -144
#define VOLUME_MAX 0
#define USER_AGENT "iTunes/11.0.4 (Windows; N)"
#define USER_NAME "iTunes"
#define DEFAULT_RAOP_PORT 5000
#define UDP_DEFAULT_AUDIO_PORT 6000
#define UDP_DEFAULT_CONTROL_PORT 6001
@ -85,13 +88,15 @@ struct pa_raop_client {
pa_core *core;
char *host;
uint16_t port;
char *sid;
pa_rtsp_client *rtsp;
pa_raop_protocol_t protocol;
char *sci, *sid;
char *pwd;
uint8_t jack_type;
uint8_t jack_status;
pa_raop_protocol_t protocol;
int encryption; /* Enable encryption? */
pa_raop_secret *aes;
@ -125,6 +130,9 @@ struct pa_raop_client {
uint32_t udp_sync_interval;
uint32_t udp_sync_count;
pa_raop_client_auth_cb_t udp_auth_callback;
void *udp_auth_userdata;
pa_raop_client_setup_cb_t udp_setup_callback;
void *udp_setup_userdata;
@ -576,7 +584,7 @@ static void do_rtsp_announce(pa_raop_client *c) {
pa_xfree(sdp);
}
static void tcp_rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist* headers, void *userdata) {
static void tcp_rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_rtsp_status status, pa_headerlist* headers, void *userdata) {
pa_raop_client* c = userdata;
pa_assert(c);
pa_assert(rtsp);
@ -675,12 +683,13 @@ static void tcp_rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist
}
}
static void udp_rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist *headers, void *userdata) {
static void udp_rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_rtsp_status status, pa_headerlist *headers, void *userdata) {
pa_raop_client *c = userdata;
pa_assert(c);
pa_assert(rtsp);
pa_assert(rtsp == c->rtsp);
pa_assert(STATUS_OK == status);
switch (state) {
case STATE_CONNECT: {
@ -982,6 +991,178 @@ static void udp_rtsp_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_headerlist
}
}
static void rtsp_authentication_cb(pa_rtsp_client *rtsp, pa_rtsp_state state, pa_rtsp_status status, pa_headerlist *headers, void *userdata) {
pa_raop_client *c = userdata;
pa_assert(c);
pa_assert(rtsp);
pa_assert(rtsp == c->rtsp);
switch (state) {
case STATE_CONNECT: {
char *sci = NULL, *sac = NULL;
uint16_t rac;
struct {
uint32_t ci1;
uint32_t ci2;
} rci;
pa_random(&rci, sizeof(rci));
/* Generate a random Client-Instance number */
sci = pa_sprintf_malloc("%08x%08x",rci.ci1, rci.ci2);
pa_rtsp_add_header(c->rtsp, "Client-Instance", sci);
pa_random(&rac, sizeof(rac));
/* Generate a random Apple-Challenge key */
pa_raop_base64_encode(&rac, 8*sizeof(rac), &sac);
pa_log_debug ("APPLECHALLENGE >> %s | %d", sac, (int) sizeof(rac));
rtrimchar(sac, '=');
pa_rtsp_add_header(c->rtsp, "Apple-Challenge", sac);
pa_rtsp_options(c->rtsp);
pa_xfree(sac);
pa_xfree(sci);
break;
}
case STATE_OPTIONS: {
static bool waiting = false;
const char *current = NULL;
char space[] = " ";
char *token,*ath = NULL;
char *publ, *wath, *mth, *val;
char *realm = NULL, *nonce = NULL, *response = NULL;
char comma[] = ",";
pa_log_debug("RAOP: OPTIONS");
/* We do not consider the Apple-Response */
pa_rtsp_remove_header(c->rtsp, "Apple-Challenge");
if (STATUS_UNAUTHORIZED == status) {
wath = pa_xstrdup(pa_headerlist_gets(headers, "WWW-Authenticate"));
if (true == waiting) {
pa_xfree(wath);
goto failure;
}
if (wath)
mth = pa_split(wath, space, &current);
while ((token = pa_split(wath, comma, &current))) {
val = NULL;
if ((val = strstr(token, "="))) {
if (NULL == realm && val > strstr(token, "realm"))
realm = pa_xstrdup(val + 2);
else if (NULL == nonce && val > strstr(token, "nonce"))
nonce = pa_xstrdup(val + 2);
val = NULL;
}
pa_xfree(token);
}
if (pa_safe_streq(mth, "Basic")) {
rtrimchar(realm, '\"');
pa_raop_basic_response(USER_NAME, c->pwd, &response);
ath = pa_sprintf_malloc("Basic %s",
response);
pa_xfree(response);
pa_xfree(realm);
} else if (pa_safe_streq(mth, "Digest")) {
rtrimchar(realm, '\"');
rtrimchar(nonce, '\"');
pa_raop_digest_response(USER_NAME, realm, c->pwd, nonce, "*", &response);
ath = pa_sprintf_malloc("Digest username=\"%s\", realm=\"%s\", nonce=\"%s\", uri=\"*\", response=\"%s\"",
USER_NAME, realm, nonce,
response);
pa_xfree(response);
pa_xfree(realm);
pa_xfree(nonce);
} else {
pa_log_error("unsupported authentication method: %s", mth);
pa_xfree(wath);
pa_xfree(mth);
goto error;
}
pa_xfree(wath);
pa_xfree(mth);
pa_rtsp_add_header(c->rtsp, "Authorization", ath);
pa_xfree(ath);
waiting = true;
pa_rtsp_options(c->rtsp);
break;
}
if (STATUS_OK == status) {
publ = pa_xstrdup(pa_headerlist_gets(headers, "Public"));
c->sci = pa_xstrdup(pa_rtsp_get_header(c->rtsp, "Client-Instance"));
if (c->pwd)
pa_xfree(c->pwd);
pa_xfree(publ);
c->pwd = NULL;
}
if (c->udp_auth_callback)
c->udp_auth_callback((int) status, c->udp_auth_userdata);
pa_rtsp_client_free(c->rtsp);
c->rtsp = NULL;
waiting = false;
break;
failure:
if (c->udp_auth_callback)
c->udp_auth_callback((int) STATUS_UNAUTHORIZED, c->udp_auth_userdata);
pa_rtsp_client_free(c->rtsp);
c->rtsp = NULL;
pa_log_error("aborting RTSP authentication, wrong password");
waiting = false;
break;
error:
if (c->udp_auth_callback)
c->udp_auth_callback((int) status, c->udp_auth_userdata);
pa_rtsp_client_free(c->rtsp);
c->rtsp = NULL;
pa_log_error("aborting RTSP authentication, unexpected failure");
waiting = false;
break;
}
case STATE_ANNOUNCE:
case STATE_SETUP:
case STATE_RECORD:
case STATE_SET_PARAMETER:
case STATE_FLUSH:
case STATE_TEARDOWN:
case STATE_DISCONNECTED:
default: {
if (c->udp_auth_callback)
c->udp_auth_callback((int) STATUS_BAD_REQUEST, c->udp_auth_userdata);
pa_rtsp_client_free(c->rtsp);
c->rtsp = NULL;
if (c->sci)
pa_xfree(c->sci);
c->sci = NULL;
break;
}
}
}
pa_raop_client* pa_raop_client_new(pa_core *core, const char *host, pa_raop_protocol_t protocol) {
pa_raop_client* c;
pa_parsed_address a;
@ -1047,15 +1228,40 @@ void pa_raop_client_free(pa_raop_client *c) {
if (c->sid)
pa_xfree(c->sid);
if (c->sci)
pa_xfree(c->sci);
c->sci = c->sid = NULL;
if (c->aes)
pa_raop_secret_free(c->aes);
if (c->rtsp)
pa_rtsp_client_free(c->rtsp);
pa_xfree(c->host);
c->rtsp = NULL;
pa_xfree(c->host);
pa_xfree(c);
}
int pa_raop_client_authenticate (pa_raop_client *c, const char *password) {
pa_assert(c);
if (c->rtsp || c->pwd) {
pa_log_debug("Connection already in progress");
return 0;
}
c->pwd = NULL;
if (password)
c->pwd = pa_xstrdup(password);
c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, c->port, USER_AGENT);
pa_assert(c->rtsp);
pa_rtsp_set_callback(c->rtsp, rtsp_authentication_cb, c);
return pa_rtsp_connect(c->rtsp);
}
int pa_raop_client_connect(pa_raop_client *c) {
char *sci;
struct {
@ -1074,7 +1280,7 @@ int pa_raop_client_connect(pa_raop_client *c) {
if (c->protocol == RAOP_TCP)
c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, c->port, "iTunes/4.6 (Macintosh; U; PPC Mac OS X 10.3)");
else
c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, c->port, "iTunes/7.6.2 (Windows; N;)");
c->rtsp = pa_rtsp_client_new(c->core->mainloop, c->host, c->port, USER_AGENT);
/* Generate random instance id. */
pa_random(&rand_data, sizeof(rand_data));
@ -1116,6 +1322,17 @@ int pa_raop_client_teardown(pa_raop_client *c) {
return rv;
}
int pa_raop_client_udp_is_authenticated(pa_raop_client *c) {
int rv = 0;
pa_assert(c);
if (c->sci != NULL)
rv = 1;
return rv;
}
int pa_raop_client_udp_is_alive(pa_raop_client *c) {
int rv = 0;
@ -1147,7 +1364,6 @@ int pa_raop_client_udp_stream(pa_raop_client *c) {
if (!c->is_recording) {
c->udp_first_packet = true;
c->udp_sync_count = 0;
c->is_recording = true;
}
@ -1326,6 +1542,14 @@ ssize_t pa_raop_client_udp_send_audio_packet(pa_raop_client *c, pa_memchunk *blo
return len;
}
void pa_raop_client_set_encryption(pa_raop_client *c, int encryption) {
pa_assert(c);
c->encryption = encryption;
if (c->encryption)
c->aes = pa_raop_secret_new();
}
/* Adjust volume so that it fits into VOLUME_DEF <= v <= 0 dB */
pa_volume_t pa_raop_client_adjust_volume(pa_raop_client *c, pa_volume_t volume) {
double minv, maxv;
@ -1469,12 +1693,11 @@ void pa_raop_client_tcp_set_closed_callback(pa_raop_client *c, pa_raop_client_cl
c->tcp_closed_userdata = userdata;
}
void pa_raop_client_set_encryption(pa_raop_client *c, int encryption) {
void pa_raop_client_udp_set_auth_callback(pa_raop_client *c, pa_raop_client_auth_cb_t callback, void *userdata) {
pa_assert(c);
c->encryption = encryption;
if (c->encryption)
c->aes = pa_raop_secret_new();
c->udp_auth_callback = callback;
c->udp_auth_userdata = userdata;
}
void pa_raop_client_udp_set_setup_callback(pa_raop_client *c, pa_raop_client_setup_cb_t callback, void *userdata) {

View file

@ -37,10 +37,12 @@ typedef struct pa_raop_client pa_raop_client;
pa_raop_client* pa_raop_client_new(pa_core *core, const char *host, pa_raop_protocol_t protocol);
void pa_raop_client_free(pa_raop_client *c);
int pa_raop_client_authenticate (pa_raop_client *c, const char *password);
int pa_raop_client_connect(pa_raop_client *c);
int pa_raop_client_flush(pa_raop_client *c);
int pa_raop_client_teardown(pa_raop_client *c);
int pa_raop_client_udp_is_authenticated(pa_raop_client *c);
int pa_raop_client_udp_is_alive(pa_raop_client *c);
int pa_raop_client_udp_can_stream(pa_raop_client *c);
int pa_raop_client_udp_stream(pa_raop_client *c);
@ -61,6 +63,8 @@ void pa_raop_client_tcp_set_callback(pa_raop_client *c, pa_raop_client_cb_t call
typedef void (*pa_raop_client_closed_cb_t)(void *userdata);
void pa_raop_client_tcp_set_closed_callback(pa_raop_client *c, pa_raop_client_closed_cb_t callback, void *userdata);
typedef void (*pa_raop_client_auth_cb_t)(int status, void *userdata);
void pa_raop_client_udp_set_auth_callback(pa_raop_client *c, pa_raop_client_auth_cb_t callback, void *userdata);
typedef void (*pa_raop_client_setup_cb_t)(int control_fd, int timing_fd, void *userdata);
void pa_raop_client_udp_set_setup_callback(pa_raop_client *c, pa_raop_client_setup_cb_t callback, void *userdata);

View file

@ -35,6 +35,7 @@
#include <pulse/xmalloc.h>
#include <pulsecore/core-util.h>
#include <pulsecore/macro.h>
#include "raop_util.h"
@ -168,3 +169,42 @@ int pa_raop_md5_hash(const char *data, int len, char **str) {
s[MD5_HASH_LENGTH] = 0;
return strlen(s);
}
int pa_raop_basic_response(const char *user, const char *pwd, char **str) {
char *tmp, *B = NULL;
pa_assert(str);
tmp = pa_sprintf_malloc("%s:%s", user, pwd);
pa_raop_base64_encode(tmp, strlen(tmp), &B);
pa_xfree(tmp);
*str = B;
return strlen(B);
}
int pa_raop_digest_response(const char *user, const char *realm, const char *password,
const char *nonce, const char *uri, char **str) {
char *A1, *HA1, *A2, *HA2;
char *tmp, *KD = NULL;
pa_assert(str);
A1 = pa_sprintf_malloc("%s:%s:%s", user, realm, password);
pa_raop_md5_hash(A1, strlen(A1), &HA1);
pa_xfree(A1);
A2 = pa_sprintf_malloc("OPTIONS:%s", uri);
pa_raop_md5_hash(A2, strlen(A2), &HA2);
pa_xfree(A2);
tmp = pa_sprintf_malloc("%s:%s:%s", HA1, nonce, HA2);
pa_raop_md5_hash(tmp, strlen(tmp), &KD);
pa_xfree(tmp);
pa_xfree(HA1);
pa_xfree(HA2);
*str = KD;
return strlen(KD);
}

View file

@ -32,4 +32,8 @@ int pa_raop_base64_decode(const char *str, void *data);
int pa_raop_md5_hash(const char *data, int len, char **str);
int pa_raop_basic_response(const char *user, const char *pwd, char **str);
int pa_raop_digest_response(const char *user, const char *realm, const char *password,
const char *nonce, const char *uri, char **str);
#endif

View file

@ -59,6 +59,7 @@ struct pa_rtsp_client {
const char *useragent;
pa_rtsp_state state;
pa_rtsp_status status;
uint8_t waiting;
pa_headerlist* headers;
@ -119,8 +120,8 @@ void pa_rtsp_client_free(pa_rtsp_client *c) {
}
static void headers_read(pa_rtsp_client *c) {
char* token;
char delimiters[] = ";";
char* token;
pa_assert(c);
pa_assert(c->response_headers);
@ -165,14 +166,14 @@ static void headers_read(pa_rtsp_client *c) {
}
/* Call our callback */
c->callback(c, c->state, c->response_headers, c->userdata);
c->callback(c, c->state, c->status, c->response_headers, c->userdata);
}
static void line_callback(pa_ioline *line, const char *s, void *userdata) {
pa_rtsp_client *c = userdata;
char *delimpos;
char *s2, *s2p;
pa_rtsp_client *c = userdata;
pa_assert(line);
pa_assert(c);
pa_assert(c->callback);
@ -180,7 +181,7 @@ static void line_callback(pa_ioline *line, const char *s, void *userdata) {
if (!s) {
/* Keep the ioline/iochannel open as they will be freed automatically */
c->ioline = NULL;
c->callback(c, STATE_DISCONNECTED, NULL, c->userdata);
c->callback(c, STATE_DISCONNECTED, STATUS_NO_RESPONSE, NULL, c->userdata);
return;
}
@ -191,17 +192,35 @@ static void line_callback(pa_ioline *line, const char *s, void *userdata) {
*s2p = '\0';
s2p -= 1;
}
if (c->waiting && pa_streq(s2, "RTSP/1.0 200 OK")) {
c->waiting = 0;
if (c->response_headers)
pa_headerlist_free(c->response_headers);
c->response_headers = pa_headerlist_new();
c->status = STATUS_OK;
c->waiting = 0;
goto exit;
} else if (c->waiting && pa_streq(s2, "RTSP/1.0 401 Unauthorized")) {
if (c->response_headers)
pa_headerlist_free(c->response_headers);
c->response_headers = pa_headerlist_new();
c->status = STATUS_UNAUTHORIZED;
c->waiting = 0;
goto exit;
} else if (c->waiting) {
pa_log_warn("Unexpected/Unhandled response: %s", s2);
if (pa_streq(s2, "RTSP/1.0 400 Bad Request"))
c->status = STATUS_BAD_REQUEST;
else if (pa_streq(s2, "RTSP/1.0 500 Internal Server Error"))
c->status = STATUS_INTERNAL_ERROR;
else
c->status = STATUS_NO_RESPONSE;
goto exit;
}
if (c->waiting) {
pa_log_warn("Unexpected response: %s", s2);
goto exit;
}
if (!strlen(s2)) {
/* End of headers */
/* We will have a header left from our looping iteration, so add it in :) */
@ -228,7 +247,7 @@ static void line_callback(pa_ioline *line, const char *s, void *userdata) {
if (c->last_header && ' ' == s2[0]) {
pa_assert(c->header_buffer);
/* Add this line to the buffer (sans the space. */
/* Add this line to the buffer (sans the space) */
pa_strbuf_puts(c->header_buffer, &(s2[1]));
goto exit;
}
@ -270,6 +289,7 @@ static void line_callback(pa_ioline *line, const char *s, void *userdata) {
/* Save the header name */
c->last_header = pa_xstrdup(s2);
exit:
pa_xfree(s2);
}
@ -317,7 +337,7 @@ static void on_connection(pa_socket_client *sc, pa_iochannel *io, void *userdata
pa_log_debug("Established RTSP connection from local ip %s", c->localip);
if (c->callback)
c->callback(c, c->state, NULL, c->userdata);
c->callback(c, c->state, STATUS_OK, NULL, c->userdata);
}
int pa_rtsp_connect(pa_rtsp_client *c) {
@ -336,6 +356,7 @@ int pa_rtsp_connect(pa_rtsp_client *c) {
pa_socket_client_set_callback(c->sc, on_connection, c);
c->waiting = 1;
c->state = STATE_CONNECT;
c->status = STATUS_NO_RESPONSE;
return 0;
}
@ -368,12 +389,25 @@ uint32_t pa_rtsp_serverport(pa_rtsp_client *c) {
return c->rtp_port;
}
bool pa_rtsp_exec_ready(const pa_rtsp_client *c) {
pa_assert(c);
return c->url != NULL && c->ioline != NULL;
}
void pa_rtsp_set_url(pa_rtsp_client *c, const char *url) {
pa_assert(c);
c->url = pa_xstrdup(url);
}
bool pa_rtsp_has_header(pa_rtsp_client *c, const char *key) {
pa_assert(c);
pa_assert(key);
return pa_headerlist_contains(c->headers, key);
}
void pa_rtsp_add_header(pa_rtsp_client *c, const char *key, const char *value) {
pa_assert(c);
pa_assert(key);
@ -382,6 +416,13 @@ void pa_rtsp_add_header(pa_rtsp_client *c, const char *key, const char *value) {
pa_headerlist_puts(c->headers, key, value);
}
const char* pa_rtsp_get_header(pa_rtsp_client *c, const char *key) {
pa_assert(c);
pa_assert(key);
return pa_headerlist_gets(c->headers, key);
}
void pa_rtsp_remove_header(pa_rtsp_client *c, const char *key) {
pa_assert(c);
pa_assert(key);
@ -389,12 +430,6 @@ void pa_rtsp_remove_header(pa_rtsp_client *c, const char *key) {
pa_headerlist_remove(c->headers, key);
}
bool pa_rtsp_exec_ready(const pa_rtsp_client *c) {
pa_assert(c);
return c->url != NULL && c->ioline != NULL;
}
static int rtsp_exec(pa_rtsp_client *c, const char *cmd,
const char *content_type, const char *content,
int expect_response,
@ -527,17 +562,6 @@ int pa_rtsp_record(pa_rtsp_client *c, uint16_t *seq, uint32_t *rtptime) {
return rv;
}
int pa_rtsp_teardown(pa_rtsp_client *c) {
int rv;
pa_assert(c);
c->state = STATE_TEARDOWN;
rv = rtsp_exec(c, "TEARDOWN", NULL, NULL, 0, NULL);
return rv;
}
int pa_rtsp_setparameter(pa_rtsp_client *c, const char *param) {
int rv;
@ -570,3 +594,14 @@ int pa_rtsp_flush(pa_rtsp_client *c, uint16_t seq, uint32_t rtptime) {
pa_headerlist_free(headers);
return rv;
}
int pa_rtsp_teardown(pa_rtsp_client *c) {
int rv;
pa_assert(c);
c->state = STATE_TEARDOWN;
rv = rtsp_exec(c, "TEARDOWN", NULL, NULL, 0, NULL);
return rv;
}

View file

@ -31,43 +31,53 @@
#include "headerlist.h"
typedef struct pa_rtsp_client pa_rtsp_client;
typedef enum {
STATE_CONNECT,
STATE_OPTIONS,
STATE_ANNOUNCE,
STATE_SETUP,
STATE_RECORD,
STATE_SET_PARAMETER,
STATE_FLUSH,
STATE_TEARDOWN,
STATE_SET_PARAMETER,
STATE_DISCONNECTED
} pa_rtsp_state;
typedef void (*pa_rtsp_cb_t)(pa_rtsp_client *c, pa_rtsp_state state, pa_headerlist *hl, void *userdata);
typedef enum {
STATUS_OK = 200,
STATUS_BAD_REQUEST = 400,
STATUS_UNAUTHORIZED = 401,
STATUS_NO_RESPONSE = 444,
STATUS_INTERNAL_ERROR = 500
} pa_rtsp_status;
typedef void (*pa_rtsp_cb_t)(pa_rtsp_client *c, pa_rtsp_state state, pa_rtsp_status code, pa_headerlist *headers, void *userdata);
pa_rtsp_client* pa_rtsp_client_new(pa_mainloop_api *mainloop, const char *hostname, uint16_t port, const char *useragent);
void pa_rtsp_client_free(pa_rtsp_client *c);
int pa_rtsp_connect(pa_rtsp_client *c);
void pa_rtsp_set_callback(pa_rtsp_client *c, pa_rtsp_cb_t callback, void *userdata);
void pa_rtsp_disconnect(pa_rtsp_client *c);
const char* pa_rtsp_localip(pa_rtsp_client *c);
uint32_t pa_rtsp_serverport(pa_rtsp_client *c);
void pa_rtsp_set_url(pa_rtsp_client *c, const char *url);
void pa_rtsp_add_header(pa_rtsp_client *c, const char *key, const char *value);
void pa_rtsp_remove_header(pa_rtsp_client *c, const char *key);
bool pa_rtsp_exec_ready(const pa_rtsp_client *c);
void pa_rtsp_set_url(pa_rtsp_client *c, const char *url);
bool pa_rtsp_has_header(pa_rtsp_client *c, const char *key);
void pa_rtsp_add_header(pa_rtsp_client *c, const char *key, const char *value);
const char* pa_rtsp_get_header(pa_rtsp_client *c, const char *key);
void pa_rtsp_remove_header(pa_rtsp_client *c, const char *key);
int pa_rtsp_options(pa_rtsp_client *c);
int pa_rtsp_announce(pa_rtsp_client *c, const char *sdp);
int pa_rtsp_setup(pa_rtsp_client *c, const char *transport);
int pa_rtsp_record(pa_rtsp_client *c, uint16_t *seq, uint32_t *rtptime);
int pa_rtsp_teardown(pa_rtsp_client *c);
int pa_rtsp_setparameter(pa_rtsp_client *c, const char *param);
int pa_rtsp_flush(pa_rtsp_client *c, uint16_t seq, uint32_t rtptime);
int pa_rtsp_teardown(pa_rtsp_client *c);
#endif