aria2c 必须使用未知的 TLS 协议连接到另一端，为什么？

Question

当我跑

aria2c https://www.example.com

我得到

02/24 15:33:38 [WARN] aria2c had to connect to the other side using an unknown TLS protocol. The integrity and confidentiality of the connection might be compromised.

为什么是这样？请注意，这不是特定于www.example.com; 它发生在许多（如果不是所有）主机上。

作为参考，这是（已编辑的）日志：

[INFO] [Context.cc:182] aria2 1.34.0
[INFO] [Context.cc:183] gcc 8.2.1 20181127
  built by  x86_64-pc-linux-gnu
  on        Feb  8 2019 09:32:06
[INFO] [Context.cc:185] zlib/1.2.11 libxml2/2.9.9 sqlite3/3.26.0 GnuTLS/3.6.6 nettle GMP/6.1.2 c-ares/1.15.0 libssh2/1.8.0
[INFO] [Context.cc:186] Logging started.
[DEBUG] [Context.cc:216] Not setting rlimit NO_FILE: 1024 >= 1024
[NOTICE] [Context.cc:311] Downloading 1 item(s)
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: common.c[_gnutls_x509_get_raw_field2]:1570
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: x509.c[gnutls_x509_crt_get_subject_unique_id]:3902
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: x509.c[gnutls_x509_crt_get_issuer_unique_id]:3952
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: dn.c[_gnutls_x509_compare_raw_dn]:990
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: dn.c[_gnutls_x509_compare_raw_dn]:990
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: dn.c[_gnutls_x509_compare_raw_dn]:990
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: dn.c[_gnutls_x509_compare_raw_dn]:990
[INFO] [LibgnutlsTLSContext.cc:158] 135 certificate(s) were imported.
[DEBUG] [RequestGroupMan.cc:591] 1 RequestGroup(s) added.
[DEBUG] [AbstractCommand.cc:184] CUID#7 - socket: read:0, write:0, hup:0, err:0
[DEBUG] [FeedbackURISelector.cc:162] Selected from normCands
[DEBUG] [FeedbackURISelector.cc:84] FeedbackURISelector selected https://www.example.com
[DEBUG] [AbstractCommand.cc:184] CUID#7 - socket: read:0, write:0, hup:0, err:0
[INFO] [AsyncNameResolverMan.cc:83] CUID#7 - Resolving hostname www.example.com
[DEBUG] [EpollEventPoll.cc:260] Failed to delete socket event:Bad file descriptor
[DEBUG] [AbstractCommand.cc:184] CUID#7 - socket: read:0, write:0, hup:0, err:0
[INFO] [AbstractCommand.cc:817] CUID#7 - Name resolution complete: www.example.com -> 93.184.216.34
[INFO] [HttpInitiateConnectionCommand.cc:123] CUID#7 - Connecting to 93.184.216.34:443
[DEBUG] [AbstractCommand.cc:184] CUID#7 - socket: read:0, write:0, hup:0, err:0
[DEBUG] [AbstractCommand.cc:184] CUID#7 - socket: read:0, write:1, hup:0, err:0
[DEBUG] [AbstractCommand.cc:184] CUID#7 - socket: read:0, write:1, hup:0, err:0
[DEBUG] [SocketCore.cc:926] Creating TLS session
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Allocating epoch #0
[DEBUG] [Platform.cc:86] GnuTLS: <2> added 6 protocols, 29 ciphersuites, 17 sig algos and 9 groups into priority list
[DEBUG] [SocketCore.cc:946] TLS Handshaking
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Allocating epoch #1
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: Adv. version: 3.3
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 13.02 (GNUTLS_AES_256_GCM_SHA384)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 13.03 (GNUTLS_CHACHA20_POLY1305_SHA256)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 13.01 (GNUTLS_AES_128_GCM_SHA256)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 13.04 (GNUTLS_AES_128_CCM_SHA256)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.2c (GNUTLS_ECDHE_ECDSA_AES_256_GCM_SHA384)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite cc.a9 (GNUTLS_ECDHE_ECDSA_CHACHA20_POLY1305)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.0a (GNUTLS_ECDHE_ECDSA_AES_256_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.ad (GNUTLS_ECDHE_ECDSA_AES_256_CCM)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.2b (GNUTLS_ECDHE_ECDSA_AES_128_GCM_SHA256)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.09 (GNUTLS_ECDHE_ECDSA_AES_128_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.ac (GNUTLS_ECDHE_ECDSA_AES_128_CCM)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.30 (GNUTLS_ECDHE_RSA_AES_256_GCM_SHA384)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite cc.a8 (GNUTLS_ECDHE_RSA_CHACHA20_POLY1305)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.14 (GNUTLS_ECDHE_RSA_AES_256_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.2f (GNUTLS_ECDHE_RSA_AES_128_GCM_SHA256)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.13 (GNUTLS_ECDHE_RSA_AES_128_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.9d (GNUTLS_RSA_AES_256_GCM_SHA384)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.35 (GNUTLS_RSA_AES_256_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.9d (GNUTLS_RSA_AES_256_CCM)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.9c (GNUTLS_RSA_AES_128_GCM_SHA256)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.2f (GNUTLS_RSA_AES_128_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.9c (GNUTLS_RSA_AES_128_CCM)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.9f (GNUTLS_DHE_RSA_AES_256_GCM_SHA384)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite cc.aa (GNUTLS_DHE_RSA_CHACHA20_POLY1305)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.39 (GNUTLS_DHE_RSA_AES_256_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.9f (GNUTLS_DHE_RSA_AES_256_CCM)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.9e (GNUTLS_DHE_RSA_AES_128_GCM_SHA256)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite 00.33 (GNUTLS_DHE_RSA_AES_128_CBC_SHA1)
[DEBUG] [Platform.cc:86] GnuTLS: <2> Keeping ciphersuite c0.9e (GNUTLS_DHE_RSA_AES_128_CCM)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Maximum Record Size/1) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (OCSP Status Request/5) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension OCSP Status Request/5 (5 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Client Certificate Type/19) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Server Certificate Type/20) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Supported Groups/10) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group SECP256R1 (0x17)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group SECP384R1 (0x18)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group SECP521R1 (0x19)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group X25519 (0x1d)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group FFDHE2048 (0x100)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group FFDHE3072 (0x101)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group FFDHE4096 (0x102)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group FFDHE6144 (0x103)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sent group FFDHE8192 (0x104)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Supported Groups/10 (20 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Supported EC Point Formats/11) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Supported EC Point Formats/11 (2 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (SRP/12) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Signature Algorithms/13) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (4.1) RSA-SHA256
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (8.9) RSA-PSS-SHA256
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (8.4) RSA-PSS-RSAE-SHA256
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (4.3) ECDSA-SHA256
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (8.7) EdDSA-Ed25519
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (5.1) RSA-SHA384
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (8.10) RSA-PSS-SHA384
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (8.5) RSA-PSS-RSAE-SHA384
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (5.3) ECDSA-SHA384
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (6.1) RSA-SHA512
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (8.11) RSA-PSS-SHA512
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (8.6) RSA-PSS-RSAE-SHA512
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (6.3) ECDSA-SHA512
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sent signature algo (2.1) RSA-SHA1
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Signature Algorithms/13 (30 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (SRTP/14) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Heartbeat/15) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (ALPN/16) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Encrypt-then-MAC/22) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Encrypt-then-MAC/22 (0 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Extended Master Secret/23) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Extended Master Secret/23 (0 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Session Ticket/35) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Session Ticket/35 (0 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Key Share/51) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sending key share for SECP256R1
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: sending key share for X25519
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Key Share/51 (107 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Supported Versions/43) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <2> Advertizing version 3.4
[DEBUG] [Platform.cc:86] GnuTLS: <2> Advertizing version 3.3
[DEBUG] [Platform.cc:86] GnuTLS: <2> Advertizing version 3.2
[DEBUG] [Platform.cc:86] GnuTLS: <2> Advertizing version 3.1
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Supported Versions/43 (9 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Post Handshake Auth/49) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Safe Renegotiation/65281) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Safe Renegotiation/65281 (1 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Server Name Indication/0) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <2> HSK[0x7fffd8c6c880]: sent server name: 'www.example.com'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Server Name Indication/0 (20 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Cookie/44) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Early Data/42) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (PSK Key Exchange Modes/45) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension PSK Key Exchange Modes/45 (3 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Record Size Limit/28) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Sending extension Record Size Limit/28 (2 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (ClientHello Padding/21) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Preparing extension (Pre Shared Key/41) for 'client hello'
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: CLIENT HELLO was queued [354 bytes]
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Preparing Packet Handshake(22) with length: 354 and min pad: 0
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Sent Packet[1] Handshake(22) in epoch 0 and length: 359
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1171
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[_gnutls_io_read_buffered]:589
[DEBUG] [AbstractCommand.cc:184] CUID#7 - socket: read:1, write:0, hup:0, err:0
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1171
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: SSL 3.3 Handshake packet received. Epoch 0, length: 123
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Expected Packet Handshake(22)
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Received Packet Handshake(22) with length: 123
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Decrypted Packet[0] Handshake(22) with length: 123
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: SERVER HELLO (2) was received. Length 119[119], frag offset 0, frag length: 119, sequence: 0
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1162
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[_gnutls_handshake_io_recv_int]:1413
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: Server's version: 3.3
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Parsing extension 'Supported Versions/43' (2 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Negotiated version: 3.4
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: Selected cipher suite: GNUTLS_AES_256_GCM_SHA384
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Parsing extension 'Key Share/51' (69 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: Selected group SECP256R1 (2)
[DEBUG] [Platform.cc:86] GnuTLS: <2> EXT[0x7fffd8c6c880]: client generated SECP256R1 shared key
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Preparing Packet ChangeCipherSpec(20) with length: 1 and min pad: 0
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Sent Packet[2] ChangeCipherSpec(20) in epoch 0 and length: 6
[DEBUG] [Platform.cc:86] GnuTLS: <4> REC[0x7fffd8c6c880]: Sent ChangeCipherSpec
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Initializing epoch #1
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Epoch #1 ready
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: TLS 1.3 re-key with cipher suite: GNUTLS_AES_256_GCM_SHA384
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1171
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: SSL 3.3 ChangeCipherSpec packet received. Epoch 1, length: 1
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Expected Packet Handshake(22)
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Received Packet ChangeCipherSpec(20) with length: 1
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: SSL 3.3 Application Data packet received. Epoch 1, length: 27
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Expected Packet Handshake(22)
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Received Packet Application Data(23) with length: 27
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Decrypted Packet[0] Handshake(22) with length: 10
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: ENCRYPTED EXTENSIONS (8) was received. Length 6[6], frag offset 0, frag length: 6, sequence: 0
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: parsing encrypted extensions
[DEBUG] [Platform.cc:86] GnuTLS: <4> EXT[0x7fffd8c6c880]: Parsing extension 'Server Name Indication/0' (0 bytes)
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1171
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: SSL 3.3 Application Data packet received. Epoch 1, length: 4502
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Expected Packet Handshake(22)
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Received Packet Application Data(23) with length: 4502
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Decrypted Packet[1] Handshake(22) with length: 4485
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: CERTIFICATE (11) was received. Length 4481[4481], frag offset 0, frag length: 4481, sequence: 0
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1162
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[_gnutls_handshake_io_recv_int]:1413
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: parsing certificate message
[DEBUG] [Platform.cc:86] GnuTLS: <4> Found OCSP response on cert 0
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1171
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: SSL 3.3 Application Data packet received. Epoch 1, length: 281
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Expected Packet Handshake(22)
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Received Packet Application Data(23) with length: 281
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Decrypted Packet[2] Handshake(22) with length: 264
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: CERTIFICATE VERIFY (15) was received. Length 260[260], frag offset 0, frag length: 260, sequence: 0
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: Parsing certificate verify
[DEBUG] [Platform.cc:86] GnuTLS: <4> HSK[0x7fffd8c6c880]: verifying TLS 1.3 handshake data using RSA-PSS-RSAE-SHA256
[DEBUG] [Platform.cc:86] GnuTLS: <3> ASSERT: buffers.c[get_last_packet]:1171
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: SSL 3.3 Application Data packet received. Epoch 1, length: 69
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Expected Packet Handshake(22)
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Received Packet Application Data(23) with length: 69
[DEBUG] [Platform.cc:86] GnuTLS: <5> REC[0x7fffd8c6c880]: Decrypted Packet[3] Handshake(22) with length:

    

Answer 1

您的日志表明aria2c正在使用 GnuTLS 库，该库选择了 TLS 1.3，因为 GnuTLS 库和服务器都支持它。

但是根据这个补丁，aria2c直到 2019 年 4 月 7日才知道 TLS 1.3 的存在。而且由于您的问题日期是 2 月 24 日，因此您的日志片段显然比该补丁更旧。

所以，这只是 GnuTLS 库报告它使用 TLS 1.3 并且aria2c不了解“TLS 1.3”是什么。

一旦您更新aria2c到包含该补丁的版本，aria2c就会理解 GnuTLS 在报告使用 TLS 1.3 的连接时所说的内容，并且能够正确地向用户报告，这样问题就会消失。

不幸的是，在撰写本文时，最新版本是 1.34.0，它于 2018 年 5 月发布，因此它太旧，无法包含 TLS 1.3 补丁。在创建新发布版本之前aria2c，获得aria2c支持 TLS 1.3 且没有那些烦人消息的版本的唯一方法是从 GitHub 获取最新源代码并自行编译，或者找人分发aria2c1.34的修改版本0.0本补丁回迁英寸

aria2c 1.35.0 版本于 2019 年 10 月 6 日发布，该版本最终包含 TLS 1.3 支持。