1SSL_CTX_SET_TLSEXT_USE_SRTP(3ossl) OpenSSL SSL_CTX_SET_TLSEXT_USE_SRTP(3ossl)
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6 SSL_CTX_set_tlsext_use_srtp, SSL_set_tlsext_use_srtp,
7 SSL_get_srtp_profiles, SSL_get_selected_srtp_profile - Configure and
8 query SRTP support
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11 #include <openssl/srtp.h>
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13 int SSL_CTX_set_tlsext_use_srtp(SSL_CTX *ctx, const char *profiles);
14 int SSL_set_tlsext_use_srtp(SSL *ssl, const char *profiles);
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16 STACK_OF(SRTP_PROTECTION_PROFILE) *SSL_get_srtp_profiles(SSL *ssl);
17 SRTP_PROTECTION_PROFILE *SSL_get_selected_srtp_profile(SSL *s);
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20 SRTP is the Secure Real-Time Transport Protocol. OpenSSL implements
21 support for the "use_srtp" DTLS extension defined in RFC5764. This
22 provides a mechanism for establishing SRTP keying material, algorithms
23 and parameters using DTLS. This capability may be used as part of an
24 implementation that conforms to RFC5763. OpenSSL does not implement
25 SRTP itself or RFC5763. Note that OpenSSL does not support the use of
26 SRTP Master Key Identifiers (MKIs). Also note that this extension is
27 only supported in DTLS. Any SRTP configuration will be ignored if a TLS
28 connection is attempted.
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30 An OpenSSL client wishing to send the "use_srtp" extension should call
31 SSL_CTX_set_tlsext_use_srtp() to set its use for all SSL objects
32 subsequently created from an SSL_CTX. Alternatively a client may call
33 SSL_set_tlsext_use_srtp() to set its use for an individual SSL object.
34 The profiles parameters should point to a NUL-terminated, colon
35 delimited list of SRTP protection profile names.
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37 The currently supported protection profile names are:
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39 SRTP_AES128_CM_SHA1_80
40 This corresponds to SRTP_AES128_CM_HMAC_SHA1_80 defined in RFC5764.
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42 SRTP_AES128_CM_SHA1_32
43 This corresponds to SRTP_AES128_CM_HMAC_SHA1_32 defined in RFC5764.
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45 SRTP_AEAD_AES_128_GCM
46 This corresponds to the profile of the same name defined in
47 RFC7714.
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49 SRTP_AEAD_AES_256_GCM
50 This corresponds to the profile of the same name defined in
51 RFC7714.
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53 Supplying an unrecognised protection profile name will result in an
54 error.
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56 An OpenSSL server wishing to support the "use_srtp" extension should
57 also call SSL_CTX_set_tlsext_use_srtp() or SSL_set_tlsext_use_srtp() to
58 indicate the protection profiles that it is willing to negotiate.
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60 The currently configured list of protection profiles for either a
61 client or a server can be obtained by calling SSL_get_srtp_profiles().
62 This returns a stack of SRTP_PROTECTION_PROFILE objects. The memory
63 pointed to in the return value of this function should not be freed by
64 the caller.
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66 After a handshake has been completed the negotiated SRTP protection
67 profile (if any) can be obtained (on the client or the server) by
68 calling SSL_get_selected_srtp_profile(). This function will return NULL
69 if no SRTP protection profile was negotiated. The memory returned from
70 this function should not be freed by the caller.
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72 If an SRTP protection profile has been successfully negotiated then the
73 SRTP keying material (on both the client and server) should be obtained
74 via a call to SSL_export_keying_material(3). This call should provide a
75 label value of "EXTRACTOR-dtls_srtp" and a NULL context value
76 (use_context is 0). The total length of keying material obtained should
77 be equal to two times the sum of the master key length and the salt
78 length as defined for the protection profile in use. This provides the
79 client write master key, the server write master key, the client write
80 master salt and the server write master salt in that order.
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83 SSL_CTX_set_tlsext_use_srtp() and SSL_set_tlsext_use_srtp() return 0 on
84 success or 1 on error.
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86 SSL_get_srtp_profiles() returns a stack of SRTP_PROTECTION_PROFILE
87 objects on success or NULL on error or if no protection profiles have
88 been configured.
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90 SSL_get_selected_srtp_profile() returns a pointer to an
91 SRTP_PROTECTION_PROFILE object if one has been negotiated or NULL
92 otherwise.
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95 ssl(7), SSL_export_keying_material(3)
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98 Copyright 2017-2018 The OpenSSL Project Authors. All Rights Reserved.
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100 Licensed under the Apache License 2.0 (the "License"). You may not use
101 this file except in compliance with the License. You can obtain a copy
102 in the file LICENSE in the source distribution or at
103 <https://www.openssl.org/source/license.html>.
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1073.0.5 2022-11-01SSL_CTX_SET_TLSEXT_USE_SRTP(3ossl)