#include "libavutil/avassert.h"
#include "libavutil/mem.h"
#include "network.h"
#include "os_support.h"
#include "libavutil/random_seed.h"
#include "url.h"
#include "tls.h"
#include "libavutil/opt.h"
#include <openssl/bio.h>
#include <openssl/ssl.h>
#include <openssl/err.h>
#include <openssl/x509v3.h>

Data Structures
struct	TLSContext

Functions
static int	pkey_to_pem_string (EVP_PKEY pkey, char out, size_t out_sz)
	Convert an EVP_PKEY to a PEM string. More...

static int	cert_to_pem_string (X509 cert, char out, size_t out_sz)
	Convert an X509 certificate to a PEM string. More...

static int	x509_fingerprint (X509 cert, char *fingerprint)
	Generate a SHA-256 fingerprint of an X.509 certificate. More...

int	ff_ssl_read_key_cert (char key_url, char cert_url, char key_buf, size_t key_sz, char cert_buf, size_t cert_sz, char **fingerprint)

static int	openssl_gen_private_key (EVP_PKEY **pkey)

static int	openssl_gen_certificate (EVP_PKEY pkey, X509 cert, char *fingerprint)

int	ff_ssl_gen_key_cert (char key_buf, size_t key_sz, char cert_buf, size_t cert_sz, char **fingerprint)

static EVP_PKEY *	pkey_from_pem_string (const char *pem_str, int is_priv)
	Deserialize a PEM-encoded private or public key from a NUL-terminated C string. More...

static X509 *	cert_from_pem_string (const char *pem_str)
	Deserialize a PEM-encoded certificate from a NUL-terminated C string. More...

static const char *	openssl_get_error (TLSContext *c)
	Retrieves the error message for the latest OpenSSL error. More...

int	ff_tls_set_external_socket (URLContext h, URLContext sock)

int	ff_dtls_export_materials (URLContext h, char dtls_srtp_materials, size_t materials_sz)

static int	print_ssl_error (URLContext *h, int ret)

static int	tls_close (URLContext *h)

static int	url_bio_create (BIO *b)

static int	url_bio_destroy (BIO *b)

static int	url_bio_bread (BIO b, char buf, int len)

static int	url_bio_bwrite (BIO b, const char buf, int len)

static long	url_bio_ctrl (BIO b, int cmd, long num, void ptr)

static int	url_bio_bputs (BIO b, const char str)

static av_cold void	init_bio_method (URLContext *h)

static void	openssl_info_callback (const SSL *ssl, int where, int ret)

static int	dtls_handshake (URLContext *h)

static av_cold int	openssl_init_ca_key_cert (URLContext *h)

static int	dtls_start (URLContext h, const char url, int flags, AVDictionary **options)
	Once the DTLS role has been negotiated - active for the DTLS client or passive for the DTLS server - we proceed to set up the DTLS state and initiate the handshake. More...

static int	tls_open (URLContext h, const char uri, int flags, AVDictionary **options)

static int	tls_read (URLContext h, uint8_t buf, int size)

static int	tls_write (URLContext h, const uint8_t buf, int size)

static int	tls_get_file_handle (URLContext *h)

static int	tls_get_short_seek (URLContext *h)

Variables
static const AVOption	options []

static const AVClass	tls_class

const URLProtocol	ff_tls_protocol

static const AVClass	dtls_class

const URLProtocol	ff_dtls_protocol

Function Documentation

◆ pkey_to_pem_string()

static int pkey_to_pem_string	(	EVP_PKEY *	pkey,
		char *	out,
		size_t	out_sz
	)

static

Convert an EVP_PKEY to a PEM string.

Definition at line 40 of file tls_openssl.c.

Referenced by ff_ssl_gen_key_cert(), and ff_ssl_read_key_cert().

◆ cert_to_pem_string()

static int cert_to_pem_string	(	X509 *	cert,
		char *	out,
		size_t	out_sz
	)

static

Convert an X509 certificate to a PEM string.

Definition at line 67 of file tls_openssl.c.

Referenced by ff_ssl_gen_key_cert(), and ff_ssl_read_key_cert().

◆ x509_fingerprint()

static int x509_fingerprint	(	X509 *	cert,
		char **	fingerprint
	)

static

Generate a SHA-256 fingerprint of an X.509 certificate.

Definition at line 95 of file tls_openssl.c.

Referenced by ff_ssl_read_key_cert(), and openssl_gen_certificate().

◆ ff_ssl_read_key_cert()

int ff_ssl_read_key_cert	(	char *	key_url,
		char *	cert_url,
		char *	key_buf,
		size_t	key_sz,
		char *	cert_buf,
		size_t	cert_sz,
		char **	fingerprint
	)

Definition at line 116 of file tls_openssl.c.

◆ openssl_gen_private_key()

static int openssl_gen_private_key ( EVP_PKEY ** pkey )

static

Note that secp256r1 in openssl is called NID_X9_62_prime256v1 or prime256v1 in string, not NID_secp256k1 or secp256k1 in string.

TODO: Should choose the curves in ClientHello.supported_groups, for example: Supported Group: x25519 (0x001d) Supported Group: secp256r1 (0x0017) Supported Group: secp384r1 (0x0018)

Definition at line 185 of file tls_openssl.c.

Referenced by ff_ssl_gen_key_cert(), and openssl_init_ca_key_cert().

◆ openssl_gen_certificate()

static int openssl_gen_certificate	(	EVP_PKEY *	pkey,
		X509 **	cert,
		char **	fingerprint
	)

static

Definition at line 259 of file tls_openssl.c.

Referenced by ff_ssl_gen_key_cert(), and openssl_init_ca_key_cert().

◆ ff_ssl_gen_key_cert()

int ff_ssl_gen_key_cert	(	char *	key_buf,
		size_t	key_sz,
		char *	cert_buf,
		size_t	cert_sz,
		char **	fingerprint
	)

Definition at line 341 of file tls_openssl.c.

◆ pkey_from_pem_string()

static EVP_PKEY* pkey_from_pem_string	(	const char *	pem_str,
		int	is_priv
	)

static

Deserialize a PEM-encoded private or public key from a NUL-terminated C string.

Parameters

pem_str	The PEM text, e.g. "-----BEGIN PRIVATE KEY-----\n…\n-----END PRIVATE KEY-----\n"
is_priv	If non-zero, parse as a PRIVATE key; otherwise, parse as a PUBLIC key.

Returns: EVP_PKEY* on success (must EVP_PKEY_free()), or NULL on error.

Definition at line 371 of file tls_openssl.c.

Referenced by openssl_init_ca_key_cert().

◆ cert_from_pem_string()

static X509* cert_from_pem_string ( const char * pem_str )

static

Deserialize a PEM-encoded certificate from a NUL-terminated C string.

Parameters

pem_str The PEM text, e.g. "-----BEGIN CERTIFICATE-----\n…\n-----END CERTIFICATE-----\n"

Returns: X509* on success (must X509_free()), or NULL on error.

Definition at line 401 of file tls_openssl.c.

Referenced by openssl_init_ca_key_cert().

◆ openssl_get_error()

static const char* openssl_get_error ( TLSContext * c )

static

Retrieves the error message for the latest OpenSSL error.

This function retrieves the error code from the thread's error queue, converts it to a human-readable string, and stores it in the TLSContext's error_message field. The error queue is then cleared using ERR_clear_error().

Definition at line 439 of file tls_openssl.c.

Referenced by dtls_start(), ff_dtls_export_materials(), openssl_init_ca_key_cert(), and tls_open().

◆ ff_tls_set_external_socket()

int ff_tls_set_external_socket	(	URLContext *	h,
		URLContext *	sock
	)

Definition at line 451 of file tls_openssl.c.

◆ ff_dtls_export_materials()

int ff_dtls_export_materials	(	URLContext *	h,
		char *	dtls_srtp_materials,
		size_t	materials_sz
	)

Definition at line 464 of file tls_openssl.c.

◆ print_ssl_error()

static int print_ssl_error	(	URLContext *	h,
		int	ret
	)

static

Definition at line 479 of file tls_openssl.c.

Referenced by dtls_handshake(), tls_open(), tls_read(), and tls_write().

◆ tls_close()

static int tls_close ( URLContext * h )

static

Definition at line 503 of file tls_openssl.c.

Referenced by tls_open().

◆ url_bio_create()

static int url_bio_create ( BIO * b )

static

Definition at line 519 of file tls_openssl.c.

Referenced by init_bio_method().

◆ url_bio_destroy()

static int url_bio_destroy ( BIO * b )

static

Definition at line 527 of file tls_openssl.c.

Referenced by init_bio_method().

◆ url_bio_bread()

static int url_bio_bread	(	BIO *	b,
		char *	buf,
		int	len
	)

static

Definition at line 532 of file tls_openssl.c.

Referenced by init_bio_method().

◆ url_bio_bwrite()

static int url_bio_bwrite	(	BIO *	b,
		const char *	buf,
		int	len
	)

static

Definition at line 562 of file tls_openssl.c.

Referenced by init_bio_method(), and url_bio_bputs().

◆ url_bio_ctrl()

static long url_bio_ctrl	(	BIO *	b,
		int	cmd,
		long	num,
		void *	ptr
	)

static

Definition at line 578 of file tls_openssl.c.

Referenced by init_bio_method().

◆ url_bio_bputs()

static int url_bio_bputs	(	BIO *	b,
		const char *	str
	)

static

Definition at line 587 of file tls_openssl.c.

Referenced by init_bio_method().

◆ init_bio_method()

static av_cold void init_bio_method ( URLContext * h )

static

Definition at line 592 of file tls_openssl.c.

Referenced by dtls_start(), and tls_open().

◆ openssl_info_callback()

static void openssl_info_callback	(	const SSL *	ssl,
		int	where,
		int	ret
	)

static

Definition at line 609 of file tls_openssl.c.

Referenced by dtls_start(), and tls_open().

◆ dtls_handshake()

static int dtls_handshake ( URLContext * h )

static

Definition at line 628 of file tls_openssl.c.

Referenced by dtls_start().

◆ openssl_init_ca_key_cert()

static av_cold int openssl_init_ca_key_cert ( URLContext * h )

static

Definition at line 657 of file tls_openssl.c.

Referenced by dtls_start(), and tls_open().

◆ dtls_start()

static int dtls_start	(	URLContext *	h,
		const char *	url,
		int	flags,
		AVDictionary **	options
	)

static

Once the DTLS role has been negotiated - active for the DTLS client or passive for the DTLS server - we proceed to set up the DTLS state and initiate the handshake.

The profile for OpenSSL's SRTP is SRTP_AES128_CM_SHA1_80, see ssl/d1_srtp.c. The profile for FFmpeg's SRTP is SRTP_AES128_CM_HMAC_SHA1_80, see libavformat/srtp.c.

We have set the MTU to fragment the DTLS packet. It is important to note that the packet is split to ensure that each handshake packet is smaller than the MTU.

During initialization, we only need to call SSL_do_handshake once because SSL_read consumes the handshake message if the handshake is incomplete. To simplify maintenance, we initiate the handshake for both the DTLS server and client after sending out the ICE response in the start_active_handshake function. It's worth noting that although the DTLS server may receive the ClientHello immediately after sending out the ICE response, this shouldn't be an issue as the handshake function is called before any DTLS packets are received.

The SSL_do_handshake can't be called if DTLS hasn't prepare for udp.

Definition at line 745 of file tls_openssl.c.

◆ tls_open()

static int tls_open	(	URLContext *	h,
		const char *	uri,
		int	flags,
		AVDictionary **	options
	)

static

Definition at line 845 of file tls_openssl.c.

◆ tls_read()

static int tls_read	(	URLContext *	h,
		uint8_t *	buf,
		int	size
	)

static

Definition at line 915 of file tls_openssl.c.

◆ tls_write()

static int tls_write	(	URLContext *	h,
		const uint8_t *	buf,
		int	size
	)

static

Definition at line 932 of file tls_openssl.c.

◆ tls_get_file_handle()

static int tls_get_file_handle ( URLContext * h )

static

Definition at line 954 of file tls_openssl.c.

◆ tls_get_short_seek()

static int tls_get_short_seek ( URLContext * h )

static

Definition at line 961 of file tls_openssl.c.

Variable Documentation

◆ options

const AVOption options[]

static

Initial value:

= {
    TLS_COMMON_OPTIONS(TLSContext, tls_shared),
    { NULL }
}

Definition at line 968 of file tls_openssl.c.

◆ tls_class

const AVClass tls_class

static

Initial value:

= {
    .class_name = "tls",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
}

Definition at line 973 of file tls_openssl.c.

◆ ff_tls_protocol

const URLProtocol ff_tls_protocol

Initial value:

= {
    .name           = "tls",
    .url_open2      = tls_open,
    .url_read       = tls_read,
    .url_write      = tls_write,
    .url_close      = tls_close,
    .url_get_file_handle = tls_get_file_handle,
    .url_get_short_seek  = tls_get_short_seek,
    .priv_data_size = sizeof(TLSContext),
    .flags          = URL_PROTOCOL_FLAG_NETWORK,
    .priv_data_class = &tls_class,
}

Definition at line 980 of file tls_openssl.c.

◆ dtls_class

const AVClass dtls_class

static

Initial value:

= {
    .class_name = "dtls",
    .item_name  = av_default_item_name,
    .option     = options,
    .version    = LIBAVUTIL_VERSION_INT,
}

Definition at line 993 of file tls_openssl.c.

◆ ff_dtls_protocol

const URLProtocol ff_dtls_protocol

Initial value:

= {
    .name           = "dtls",
    .url_open2      = dtls_start,
    .url_handshake  = dtls_handshake,
    .url_close      = tls_close,
    .url_read       = tls_read,
    .url_write      = tls_write,
    .url_get_file_handle = tls_get_file_handle,
    .url_get_short_seek  = tls_get_short_seek,
    .priv_data_size = sizeof(TLSContext),
    .flags          = URL_PROTOCOL_FLAG_NETWORK,
    .priv_data_class = &dtls_class,
}

Definition at line 1000 of file tls_openssl.c.

Data Structures

Functions

Variables

Function Documentation

◆ pkey_to_pem_string()

◆ cert_to_pem_string()

◆ x509_fingerprint()

◆ ff_ssl_read_key_cert()

◆ openssl_gen_private_key()

◆ openssl_gen_certificate()

◆ ff_ssl_gen_key_cert()

◆ pkey_from_pem_string()

◆ cert_from_pem_string()

◆ openssl_get_error()

◆ ff_tls_set_external_socket()

◆ ff_dtls_export_materials()

◆ print_ssl_error()

◆ tls_close()

◆ url_bio_create()

◆ url_bio_destroy()

◆ url_bio_bread()

◆ url_bio_bwrite()

◆ url_bio_ctrl()

◆ url_bio_bputs()

◆ init_bio_method()

◆ openssl_info_callback()

◆ dtls_handshake()

◆ openssl_init_ca_key_cert()

◆ dtls_start()

◆ tls_open()

◆ tls_read()

◆ tls_write()

◆ tls_get_file_handle()

◆ tls_get_short_seek()

Variable Documentation

◆ options

◆ tls_class

◆ ff_tls_protocol

◆ dtls_class

◆ ff_dtls_protocol