trying to connect to server on wss protocol using libwebsockets

[seniorHelloWorldDeveloper]

I've tried using JavaScript to connect to websocket server on "wss://example.com/trade/s/
But now I am trying to rewrite it to C using libwebsockets, my code is:

static struct lws_protocols protocols[] = {
{ "ws-protocols", callback_websocket, 0, 4096 }
};

int initWebSocket() {

struct lws_context_creation_info info;
memset(&info, 0, sizeof(info));
info.port = 443;
info.gid = -1;
info.uid = -1;
info.options = LWS_SERVER_OPTION_DO_SSL_GLOBAL_INIT;
info.protocols = protocols;

info.client_ssl_ca_filepath = "C:\\certs\\ca-bundle.crt";



struct lws_context* context = lws_create_context(&info);
if (!context) {
    printf("Error creating websocket context\n");
    return -1;
}
else {
    printf("Created websocket context");
}
struct lws_client_connect_info ccinfo;
memset(&ccinfo, 0, sizeof(ccinfo));
ccinfo.context = context;

ccinfo.address = "example.com";
ccinfo.port = 443;
ccinfo.path = "wss://example.com/trade/s/";
ccinfo.host = "example.com";
ccinfo.origin = "example.com";
ccinfo.protocol = "ws-protocols";
ccinfo.ssl_connection |= LCCSCF_ALLOW_SELFSIGNED;
ccinfo.ssl_connection |= LCCSCF_SKIP_SERVER_CERT_HOSTNAME_CHECK;
ccinfo.ssl_connection |= LCCSCF_USE_SSL;

struct lws* wsi = lws_client_connect_via_info(&ccinfo);
if (!wsi) {
    printf("Failed to connect to the server\n");
    lws_context_destroy(context);
    return -1;
}

while (1) {
    lws_service(context, 0);
}

lws_context_destroy(context);
return 0;

}

But i keep getting 502 bad gateway.. I dont really get the difference between address, path, host, oorigin but I tried my best to find any info on the internet, also tried path: /trade/s/

[lws-team]

ccinfo.path is not a url. It's just the path part, probably, "trade/s" in your case.

If example.com has real certs for its https server, you do not want ALLOW_SELFSIGNED or SKIP_SERVER_CERT_HOSTNAME_CHECK either.

[seniorHelloWorldDeveloper]

Thank you, tried this one but still getting the same error, here my logs after importing certs

[2025/02/08 13:06:23:3063] D: _realloc: size 72: client ctx tcr
[2025/02/08 13:06:23:3073] I: lws_tls_client_create_vhost_context: vh default: created new client ctx 0
[2025/02/08 13:06:24:3654] I: loaded ssl_ca_filepath
[2025/02/08 13:06:24:3654] I: created client ssl context for default
[2025/02/08 13:06:24:3684] I: _lws_vhost_init_server_af: af 2
[2025/02/08 13:06:24:3694] N: [vh|0|default||443]: lws_socket_bind: source ads 0.0.0.0
[2025/02/08 13:06:24:3694] D: _realloc: size 1280: __lws_wsi_create_with_role
[2025/02/08 13:06:24:3704] D: : lws_role_transition: wsistate 0x200, ops listen
[2025/02/08 13:06:24:3714] D: _lws_vhost_init_server_af: lws_socket_bind says 443
[2025/02/08 13:06:24:3724] D: : lws_vhost_bind_wsi: vh default: wsi listen/ws-protocols, count_bound_wsi 1
[2025/02/08 13:06:24:3724] D: : __insert_wsi_socket_into_fds: tsi=0, sock=992, pos-in-fds=1
[2025/02/08 13:06:24:3734] N: __lws_lc_tag: ++ [wsi|1|listen|default||443] (2)
[2025/02/08 13:06:24:3734] I: Listening on (null):443
[2025/02/08 13:06:24:3744] I: _lws_vhost_init_server_af: af 23
[2025/02/08 13:06:24:3764] N: [vh|0|default||443]: lws_socket_bind: source ads ::
[2025/02/08 13:06:24:3764] D: _realloc: size 1280: __lws_wsi_create_with_role
[2025/02/08 13:06:24:3774] D: : lws_role_transition: wsistate 0x200, ops listen
[2025/02/08 13:06:24:3784] D: _lws_vhost_init_server_af: lws_socket_bind says 443
[2025/02/08 13:06:24:3804] D: : lws_vhost_bind_wsi: vh default: wsi listen/ws-protocols, count_bound_wsi 2
[2025/02/08 13:06:24:3834] D: : __insert_wsi_socket_into_fds: tsi=0, sock=996, pos-in-fds=2
[2025/02/08 13:06:24:3844] N: __lws_lc_tag: ++ [wsi|2|listen|default||443] (3)
[2025/02/08 13:06:24:3854] I: Listening on (null):443
[2025/02/08 13:06:24:3864] I: lws_create_context: mem: per-conn: 1280 bytes + protocol rx buf
[2025/02/08 13:06:24:3874] D: lws_cancel_service:
Created websocket context[2025/02/08 13:06:24:3894] I: lws_protocol_init:
[2025/02/08 13:06:24:3894] D: [vh|0|default||443]: lws_protocol_init_vhost: not instantiating ws-protocols
[2025/02/08 13:06:24:3914] I: [vh|0|default||443]: lws_protocol_init_vhost: init default.ws-protocols
[2025/02/08 13:06:24:3924] D: _realloc: size 1280: __lws_wsi_create_with_role
[2025/02/08 13:06:24:3934] D: : lws_role_transition: wsistate 0x200, ops (unset)
[2025/02/08 13:06:24:3954] D: : lws_vhost_bind_wsi: vh default: wsi none/none, count_bound_wsi 3
[2025/02/08 13:06:24:4014] D: _realloc: size 336: client ws struct
[2025/02/08 13:06:24:4024] D: : lws_role_transition: wsistate 0x10000200, ops h1
[2025/02/08 13:06:24:4034] I: : lws_client_connect_via_info: role binding to h1
[2025/02/08 13:06:24:4054] I: : lws_client_connect_via_info: vh default protocol binding to ws-protocols
[2025/02/08 13:06:24:4064] D: : lws_ensure_user_space: protocol pss 0, user_space=0000000000000000
[2025/02/08 13:06:24:4084] I: : lws_client_connect_via_info: : h1 ws-protocols entry
[2025/02/08 13:06:24:4104] D: _realloc: size 164: client stash
[2025/02/08 13:06:24:4144] N: __lws_lc_tag: ++ [wsicli|0|WS/h1/default/example.com] (1)
[2025/02/08 13:06:24:4154] I: lws_header_table_attach: [wsicli|0|WS/h1/default/example.com]: ah 0000000000000000 (tsi 0, count = 0) in
[2025/02/08 13:06:24:4175] D: _realloc: size 984: ah struct
[2025/02/08 13:06:24:4184] D: _realloc: size 4096: ah data
[2025/02/08 13:06:24:4204] I: _lws_create_ah: created ah 000001FCBEEFCE90 (size 4096): pool length 1
[2025/02/08 13:06:24:4214] I: lws_header_table_attach: did attach wsi [wsicli|0|WS/h1/default/example.com]: ah 000001FCBEEFCE90: count 1 (on exit)
[2025/02/08 13:06:24:4234] D: [wsicli|0|WS/h1/default/example.com]: __lws_set_timeout: 10 secs, reason 25
[2025/02/08 13:06:24:4254] D: [wsicli|0|WS/h1/default/example.com]: lws_http_client_connect_via_info2: stash 000001FCBEF5E880
[2025/02/08 13:06:24:4274] D: _realloc: size 21: strdup
[2025/02/08 13:06:24:4314] D: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_2_dnsreq: new conn on no pipeline flag
[2025/02/08 13:06:24:4334] D: [wsicli|0|WS/h1/default/example.com]: lwsi_set_state: lwsi_set_state 0x10000200 -> 0x10000201
[2025/02/08 13:06:24:4344] I: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_2_dnsreq: lookup example.com:443
[2025/02/08 13:06:24:4364] I: [wsicli|0|WS/h1/default/example.com]: lws_getaddrinfo46: getaddrinfo 'example.com' says 0
[2025/02/08 13:06:24:4374] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns: sort_dns: 000001FCBEF46E90
[2025/02/08 13:06:24:4384] D: _realloc: size 144: lws_sort_dns
[2025/02/08 13:06:24:4394] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns: unsorted entry (af 23) 2606:4700:4400::ac40:9079
[2025/02/08 13:06:24:4404] D: _realloc: size 144: lws_sort_dns
[2025/02/08 13:06:24:4434] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns: unsorted entry (af 23) 2606:4700:4400::6812:2b87
[2025/02/08 13:06:24:4484] D: _realloc: size 144: lws_sort_dns
[2025/02/08 13:06:24:4504] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns: unsorted entry (af 2) 104.18.43.135
[2025/02/08 13:06:24:4514] D: _realloc: size 144: lws_sort_dns
[2025/02/08 13:06:24:4524] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns: unsorted entry (af 2) 172.64.144.121
[2025/02/08 13:06:24:4534] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns_dump: 1: (23)2606:4700:4400::ac40:9079, gw (0)(unset), idi: 0, lbl: 0, prec: 0
[2025/02/08 13:06:24:4544] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns_dump: 2: (23)2606:4700:4400::6812:2b87, gw (0)(unset), idi: 0, lbl: 0, prec: 0
[2025/02/08 13:06:24:4554] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns_dump: 3: (2)104.18.43.135, gw (0)(unset), idi: 0, lbl: 0, prec: 0
[2025/02/08 13:06:24:4574] I: [wsicli|0|WS/h1/default/example.com]: lws_sort_dns_dump: 4: (2)172.64.144.121, gw (0)(unset), idi: 0, lbl: 0, prec: 0
[2025/02/08 13:06:24:4634] W: lws_plat_set_socket_options_ip: not implemented on windows platform
[2025/02/08 13:06:24:4634] D: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_3_connect: WAITING_CONNECT
[2025/02/08 13:06:24:4644] D: [wsicli|0|WS/h1/default/example.com]: lwsi_set_state: lwsi_set_state 0x10000201 -> 0x10000202
[2025/02/08 13:06:24:4654] D: [wsicli|0|WS/h1/default/example.com]: __insert_wsi_socket_into_fds: tsi=0, sock=1000, pos-in-fds=3
[2025/02/08 13:06:24:4664] D: [wsicli|0|WS/h1/default/example.com]: _lws_change_pollfd: fd 1000 events 768 -> 768
[2025/02/08 13:06:24:4674] D: [wsicli|0|WS/h1/default/example.com]: __lws_set_timeout: 20 secs, reason 2
[2025/02/08 13:06:24:4694] D: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_3_connect: connect: fd 1000 errno: 10035
[2025/02/08 13:06:24:4694] D: [wsicli|0|WS/h1/default/example.com]: _lws_change_pollfd: fd 1000 events 768 -> 784
[2025/02/08 13:06:24:4716] D: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_via_info: adoption cb 19 to h1 ws-protocols
[2025/02/08 13:06:24:4734] D: [wsicli|0|WS/h1/default/example.com]: _lws_change_pollfd: fd 1000 events 784 -> 768
[2025/02/08 13:06:24:4784] I: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_3_connect: source ads 2a0d:6fc2:5502:a901:708f:28a1:1da4:b2ee
[2025/02/08 13:06:24:4804] D: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_3_connect: going into connect_4
[2025/02/08 13:06:24:4804] I: [wsicli|0|WS/h1/default/example.com]: lws_client_connect_4_established: h1 ws-protocols client created own conn (raw 0) vh default st 0x202
[2025/02/08 13:06:24:4814] D: [wsicli|0|WS/h1/default/example.com]: lwsi_set_state: lwsi_set_state 0x10000202 -> 0x10000012
[2025/02/08 13:06:24:4824] D: [wsicli|0|WS/h1/default/example.com]: __lws_set_timeout: 15 secs, reason 8
[2025/02/08 13:06:24:4834] D: lws_http_client_socket_service: LRS_H1C_ISSUE_HANDSHAKE
[2025/02/08 13:06:24:4854] D: [wsicli|0|WS/h1/default/example.com]: _lws_change_pollfd: fd 1000 events 768 -> 768
[2025/02/08 13:06:24:4864] I: lws_tls_restrict_borrow: 0 -> 1
[2025/02/08 13:06:24:4874] N: lws_gate_accepts: on = 0
[2025/02/08 13:06:24:4944] I: lws_tls_reuse_session: no existing session for default_example.com_443
[2025/02/08 13:06:24:4954] I: h1 client conn using alpn list 'http/1.1'
[2025/02/08 13:06:24:5044] D: lws_ssl_get_error: 000001FCBEFB32E0 -1 -> 2 (errno 10035)
[2025/02/08 13:06:24:5054] D: [wsicli|0|WS/h1/default/example.com]: lwsi_set_state: lwsi_set_state 0x10000012 -> 0x10000204
[2025/02/08 13:06:24:5074] D: lws_client_create_tls: lws_ssl_client_connect1: 0
[2025/02/08 13:06:24:5094] D: _lws_state_transition: system: changed 1 'CONTEXT_CREATED' -> 2 'INITIALIZED'
[2025/02/08 13:06:24:5114] D: _lws_state_transition: system: changed 2 'INITIALIZED' -> 3 'IFACE_COLDPLUG'
[2025/02/08 13:06:24:5124] D: _lws_state_transition: system: changed 3 'IFACE_COLDPLUG' -> 4 'DHCP'
[2025/02/08 13:06:24:5134] D: _lws_state_transition: system: changed 4 'DHCP' -> 5 'CPD_PRE_TIME'
[2025/02/08 13:06:24:5144] D: _lws_state_transition: system: changed 5 'CPD_PRE_TIME' -> 6 'TIME_VALID'
[2025/02/08 13:06:24:5154] D: _lws_state_transition: system: changed 6 'TIME_VALID' -> 7 'CPD_POST_TIME'
[2025/02/08 13:06:24:5164] D: _lws_state_transition: system: changed 7 'CPD_POST_TIME' -> 8 'POLICY_VALID'
[2025/02/08 13:06:24:5184] D: _lws_state_transition: system: changed 8 'POLICY_VALID' -> 9 'REGISTERED'
[2025/02/08 13:06:24:5194] D: _lws_state_transition: system: changed 9 'REGISTERED' -> 10 'AUTH1'
[2025/02/08 13:06:24:5224] D: _lws_state_transition: system: changed 10 'AUTH1' -> 11 'AUTH2'
[2025/02/08 13:06:24:5244] D: _lws_state_transition: system: changed 11 'AUTH2' -> 12 'OPERATIONAL'
[2025/02/08 13:06:24:5254] I: lws_state_transition_steps: CONTEXT_CREATED -> OPERATIONAL
[2025/02/08 13:06:24:5564] D: lws_ssl_get_error: 000001FCBEFB32E0 1 -> 0 (errno 0)
[2025/02/08 13:06:24:5564] I: [wsicli|0|WS/h1/default/example.com]: lws_role_call_alpn_negotiated: 'http/1.1'
[2025/02/08 13:06:24:5594] D: rops_alpn_negotiated_h1: client 1
[2025/02/08 13:06:24:5604] I: client connect OK
[2025/02/08 13:06:24:5614] I: lws_openssl_describe_cipher: [wsicli|0|WS/h1/default/example.com]: TLS_AES_256_GCM_SHA384, TLS_AES_256_GCM_SHA384, 256 bits, TLSv1.3
[2025/02/08 13:06:24:5634] D: lws_ssl_client_connect2: SSL_connect says 0
[2025/02/08 13:06:24:5644] I: lws_tls_restrict_return_handshake: 1 -> 0
[2025/02/08 13:06:24:5654] N: lws_gate_accepts: on = 0
[2025/02/08 13:06:24:5675] I: lws_http_client_socket_service: HANDSHAKE2: [wsicli|0|WS/h1/default/example.com]: sending headers (wsistate 0x10000204), w sock 1000
[2025/02/08 13:06:24:5704] D: [wsicli|0|WS/h1/default/example.com]: lwsi_set_state: lwsi_set_state 0x10000204 -> 0x1000020b
[2025/02/08 13:06:24:5714] D: [wsicli|0|WS/h1/default/example.com]: __lws_set_timeout: 15 secs, reason 4
[2025/02/08 13:06:24:5724] D: [wsicli|0|WS/h1/default/example.com]: _lws_change_pollfd: fd 1000 events 768 -> 784
[2025/02/08 13:06:24:5734] D: [wsicli|0|WS/h1/default/example.com]: lwsi_set_state: lwsi_set_state 0x1000020b -> 0x1000020b
[2025/02/08 13:06:24:5744] D: [wsicli|0|WS/h1/default/example.com]: __lws_set_timeout: 15 secs, reason 4
[2025/02/08 13:06:24:5754] D: [wsicli|0|WS/h1/default/example.com]: _lws_change_pollfd: fd 1000 events 784 -> 768
[2025/02/08 13:06:24:5764] D: [wsicli|0|WS/h1/default/example.com]: _lws_change_pollfd: fd 1000 events 768 -> 768
[2025/02/08 13:06:26:3275] D: _realloc: size 113: lws_tls_session_add_entry
[2025/02/08 13:06:26:3275] I: lws_tls_session_new_cb: 000001FCBEDA72A0: [wsicli|0|WS/h1/default/example.com]: new default_example.com_443, ttl 7200s (default:1)
[2025/02/08 13:06:26:3315] I: lws_tls_session_new_cb: 000001FCBEECCCE0: [wsicli|0|WS/h1/default/example.com]: reuse default_example.com_443, ttl 7200s (default:1)
[2025/02/08 13:06:26:3325] D: [wsicli|0|WS/h1/default/example.com]: SSL_read says 785
[2025/02/08 13:06:26:3335] D: [wsicli|0|WS/h1/default/example.com]: lws_buflist_aware_read: lws_http_client_socket_service: ssl_capable_read 785
[2025/02/08 13:06:26:3355] D: lws_http_client_socket_service: buflist-aware-read 0 785
[2025/02/08 13:06:26:3365] D: lws_parse: unk header 16 'x-frame-options:'
[2025/02/08 13:06:26:3375] D: lws_parse: unk header 16 'referrer-policy:'
[2025/02/08 13:06:26:3385] D: lws_parse: unk header 24 'content-security-policy:'
[2025/02/08 13:06:26:3395] D: lws_parse: unk header 29 'cross-origin-embedder-policy:'
[2025/02/08 13:06:26:3415] D: lws_parse: unk header 27 'cross-origin-opener-policy:'
[2025/02/08 13:06:26:3425] D: lws_parse: unk header 29 'cross-origin-resource-policy:'
[2025/02/08 13:06:26:3435] D: lws_parse: unk header 7 'cf-ray:'
[2025/02/08 13:06:26:3455] D: lws_parse: unk header 8 'alt-svc:'
[2025/02/08 13:06:26:3465] I: lws_buflist_append_segment: len 15 first 1 0000000000000000
[2025/02/08 13:06:26:3485] D: _realloc: size 56: lws_buflist_append_segment
[2025/02/08 13:06:26:3525] D: [wsicli|0|WS/h1/default/example.com]: lws_buflist_aware_finished_consuming: added to rxflow list
[2025/02/08 13:06:26:3535] I: lws_client_interpret_server_handshake: incoming content length 15
[2025/02/08 13:06:26:3555] W: [wsicli|0|WS/h1/default/example.com]: lws_client_ws_upgrade: got bad HTTP response '502'
[2025/02/08 13:06:26:3565] I: closing connection (prot ws-protocols) due to bail2 connection error: HS: ws upgrade response not 101
[2025/02/08 13:06:26:3585] I: [wsicli|0|WS/h1/default/example.com]: __lws_close_free_wsi: caller: c hs interp
[2025/02/08 13:06:26:3605] I: [wsicli|0|WS/h1/default/example.com]: __lws_close_free_wsi: going down with stuff in buflist
[2025/02/08 13:06:26:3625] D: [wsicli|0|WS/h1/default/example.com]: __lws_close_free_wsi: real just_kill_connection A: (sockfd 1000)
[2025/02/08 13:06:26:3655] I: [wsicli|0|WS/h1/default/example.com]: __lws_close_free_wsi: real just_kill_connection: sockfd 1000
[2025/02/08 13:06:26:3675] D: [wsi|1|listen|default||443]: _lws_change_pollfd: fd 992 events 768 -> 768
[2025/02/08 13:06:26:3695] D: [wsi|2|listen|default||443]: _lws_change_pollfd: fd 996 events 768 -> 768
[2025/02/08 13:06:26:3705] D: [wsicli|0|WS/h1/default/example.com]: lwsi_set_state: lwsi_set_state 0x1000020b -> 0x10000020
[2025/02/08 13:06:26:3725] I: [wsicli|0|WS/h1/default/example.com]: __lws_close_free_wsi: cce=1
[2025/02/08 13:06:26:3745] I: lws_tls_restrict_return: 1 -> 0
[2025/02/08 13:06:26:3755] N: lws_gate_accepts: on = 0
[2025/02/08 13:06:26:3775] I: rops_destroy_role_h1: ah det due to close
[2025/02/08 13:06:26:3795] I: __lws_header_table_detach: [wsicli|0|WS/h1/default/example.com]: ah 000001FCBEEFCE90 (tsi=0, count = 1)
[2025/02/08 13:06:26:3835] I: __lws_header_table_detach: nobody usable waiting
[2025/02/08 13:06:26:3845] I: _lws_destroy_ah: freed ah 000001FCBEEFCE90 : pool length 0
[2025/02/08 13:06:26:3865] I: __lws_header_table_detach: [wsicli|0|WS/h1/default/example.com]: ah 000001FCBEEFCE90 (tsi=0, count = 0)
[2025/02/08 13:06:26:3865] D: [wsicli|0|WS/h1/default/example.com]: __lws_vhost_unbind_wsi: vh default: count_bound_wsi 2
[2025/02/08 13:06:26:3875] D: [wsicli|0|WS/h1/default/example.com]: __lws_free_wsi: tsi fds count 3
[2025/02/08 13:06:26:3885] N: __lws_lc_untag: -- [wsicli|0|WS/h1/default/example.com] (0) 1.974s
[2025/02/08 13:06:28:0073] I: [vh|0|default||443]: lws_tls_check_cert_lifetime: vhost default: no cert

[seniorHelloWorldDeveloper]

It even gets into my callback to LWS_CALLBACK_CLIENT_APPEND_HANDSHAKE_HEADER and sets the headers I've set but still getting 502

[lws-team]

... ultimately it's up to the server to choose if it likes what you sent or not, it's not up to lws.

A good trick is set -DLWS_TLS_LOG_PLAINTEXT_TX=1 -DLWS_TLS_LOG_PLAINTEXT_RX=1 on lws cmake and rebuild the lib, this will dump in plaintext what was sent and received on the link. It might be easier to see what's wrong then.

[seniorHelloWorldDeveloper]

Sorry, my bad. The server uses socket-io server and after reading some issues about it I fount our that I need to do some stuff before, thanks