Mercurial > hg > nginx
view src/mail/ngx_mail_pop3_module.c @ 9143:48691bab4474
QUIC: fixed probe-congestion deadlock.
When probe timeout expired while congestion window was exhausted, probe PINGs
could not be sent. As a result, lost packets could not be declared lost and
congestion window could not be freed for new packets. This deadlock
continued until connection idle timeout expiration.
Now PINGs are sent separately from the frame queue without congestion control,
as specified by RFC 9002, Section 7:
An endpoint MUST NOT send a packet if it would cause bytes_in_flight
(see Appendix B.2) to be larger than the congestion window, unless the
packet is sent on a PTO timer expiration (see Section 6.2) or when entering
recovery (see Section 7.3.2).
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 14 Aug 2023 08:28:30 +0400 |
parents | dc955d274130 |
children | 4538c1ffb0f8 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_event.h> #include <ngx_mail.h> #include <ngx_mail_pop3_module.h> static void *ngx_mail_pop3_create_srv_conf(ngx_conf_t *cf); static char *ngx_mail_pop3_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child); static ngx_str_t ngx_mail_pop3_default_capabilities[] = { ngx_string("TOP"), ngx_string("USER"), ngx_string("UIDL"), ngx_null_string }; static ngx_conf_bitmask_t ngx_mail_pop3_auth_methods[] = { { ngx_string("plain"), NGX_MAIL_AUTH_PLAIN_ENABLED }, { ngx_string("apop"), NGX_MAIL_AUTH_APOP_ENABLED }, { ngx_string("cram-md5"), NGX_MAIL_AUTH_CRAM_MD5_ENABLED }, { ngx_string("external"), NGX_MAIL_AUTH_EXTERNAL_ENABLED }, { ngx_null_string, 0 } }; static ngx_str_t ngx_mail_pop3_auth_methods_names[] = { ngx_string("PLAIN"), ngx_string("LOGIN"), ngx_null_string, /* APOP */ ngx_string("CRAM-MD5"), ngx_string("EXTERNAL"), ngx_null_string /* NONE */ }; static ngx_mail_protocol_t ngx_mail_pop3_protocol = { ngx_string("pop3"), ngx_string("\x04pop3"), { 110, 995, 0, 0 }, NGX_MAIL_POP3_PROTOCOL, ngx_mail_pop3_init_session, ngx_mail_pop3_init_protocol, ngx_mail_pop3_parse_command, ngx_mail_pop3_auth_state, ngx_string("-ERR internal server error" CRLF), ngx_string("-ERR SSL certificate error" CRLF), ngx_string("-ERR No required SSL certificate" CRLF) }; static ngx_command_t ngx_mail_pop3_commands[] = { { ngx_string("pop3_capabilities"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE, ngx_mail_capabilities, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_pop3_srv_conf_t, capabilities), NULL }, { ngx_string("pop3_auth"), NGX_MAIL_MAIN_CONF|NGX_MAIL_SRV_CONF|NGX_CONF_1MORE, ngx_conf_set_bitmask_slot, NGX_MAIL_SRV_CONF_OFFSET, offsetof(ngx_mail_pop3_srv_conf_t, auth_methods), &ngx_mail_pop3_auth_methods }, ngx_null_command }; static ngx_mail_module_t ngx_mail_pop3_module_ctx = { &ngx_mail_pop3_protocol, /* protocol */ NULL, /* create main configuration */ NULL, /* init main configuration */ ngx_mail_pop3_create_srv_conf, /* create server configuration */ ngx_mail_pop3_merge_srv_conf /* merge server configuration */ }; ngx_module_t ngx_mail_pop3_module = { NGX_MODULE_V1, &ngx_mail_pop3_module_ctx, /* module context */ ngx_mail_pop3_commands, /* module directives */ NGX_MAIL_MODULE, /* module type */ NULL, /* init master */ NULL, /* init module */ NULL, /* init process */ NULL, /* init thread */ NULL, /* exit thread */ NULL, /* exit process */ NULL, /* exit master */ NGX_MODULE_V1_PADDING }; static void * ngx_mail_pop3_create_srv_conf(ngx_conf_t *cf) { ngx_mail_pop3_srv_conf_t *pscf; pscf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_pop3_srv_conf_t)); if (pscf == NULL) { return NULL; } if (ngx_array_init(&pscf->capabilities, cf->pool, 4, sizeof(ngx_str_t)) != NGX_OK) { return NULL; } return pscf; } static char * ngx_mail_pop3_merge_srv_conf(ngx_conf_t *cf, void *parent, void *child) { ngx_mail_pop3_srv_conf_t *prev = parent; ngx_mail_pop3_srv_conf_t *conf = child; u_char *p; size_t size, stls_only_size; ngx_str_t *c, *d; ngx_uint_t i, m; ngx_conf_merge_bitmask_value(conf->auth_methods, prev->auth_methods, (NGX_CONF_BITMASK_SET |NGX_MAIL_AUTH_PLAIN_ENABLED)); if (conf->auth_methods & NGX_MAIL_AUTH_PLAIN_ENABLED) { conf->auth_methods |= NGX_MAIL_AUTH_LOGIN_ENABLED; } if (conf->capabilities.nelts == 0) { conf->capabilities = prev->capabilities; } if (conf->capabilities.nelts == 0) { for (d = ngx_mail_pop3_default_capabilities; d->len; d++) { c = ngx_array_push(&conf->capabilities); if (c == NULL) { return NGX_CONF_ERROR; } *c = *d; } } size = sizeof("+OK Capability list follows" CRLF) - 1 + sizeof("." CRLF) - 1; stls_only_size = size + sizeof("STLS" CRLF) - 1; c = conf->capabilities.elts; for (i = 0; i < conf->capabilities.nelts; i++) { size += c[i].len + sizeof(CRLF) - 1; if (ngx_strcasecmp(c[i].data, (u_char *) "USER") == 0) { continue; } stls_only_size += c[i].len + sizeof(CRLF) - 1; } size += sizeof("SASL") - 1 + sizeof(CRLF) - 1; for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_EXTERNAL_ENABLED; m <<= 1, i++) { if (ngx_mail_pop3_auth_methods_names[i].len == 0) { continue; } if (m & conf->auth_methods) { size += 1 + ngx_mail_pop3_auth_methods_names[i].len; } } p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->capability.len = size; conf->capability.data = p; p = ngx_cpymem(p, "+OK Capability list follows" CRLF, sizeof("+OK Capability list follows" CRLF) - 1); for (i = 0; i < conf->capabilities.nelts; i++) { p = ngx_cpymem(p, c[i].data, c[i].len); *p++ = CR; *p++ = LF; } p = ngx_cpymem(p, "SASL", sizeof("SASL") - 1); for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_EXTERNAL_ENABLED; m <<= 1, i++) { if (ngx_mail_pop3_auth_methods_names[i].len == 0) { continue; } if (m & conf->auth_methods) { *p++ = ' '; p = ngx_cpymem(p, ngx_mail_pop3_auth_methods_names[i].data, ngx_mail_pop3_auth_methods_names[i].len); } } *p++ = CR; *p++ = LF; *p++ = '.'; *p++ = CR; *p = LF; size += sizeof("STLS" CRLF) - 1; p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->starttls_capability.len = size; conf->starttls_capability.data = p; p = ngx_cpymem(p, conf->capability.data, conf->capability.len - (sizeof("." CRLF) - 1)); p = ngx_cpymem(p, "STLS" CRLF, sizeof("STLS" CRLF) - 1); *p++ = '.'; *p++ = CR; *p = LF; size = sizeof("+OK methods supported:" CRLF) - 1 + sizeof("." CRLF) - 1; for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_EXTERNAL_ENABLED; m <<= 1, i++) { if (ngx_mail_pop3_auth_methods_names[i].len == 0) { continue; } if (m & conf->auth_methods) { size += ngx_mail_pop3_auth_methods_names[i].len + sizeof(CRLF) - 1; } } p = ngx_pnalloc(cf->pool, size); if (p == NULL) { return NGX_CONF_ERROR; } conf->auth_capability.data = p; conf->auth_capability.len = size; p = ngx_cpymem(p, "+OK methods supported:" CRLF, sizeof("+OK methods supported:" CRLF) - 1); for (m = NGX_MAIL_AUTH_PLAIN_ENABLED, i = 0; m <= NGX_MAIL_AUTH_EXTERNAL_ENABLED; m <<= 1, i++) { if (ngx_mail_pop3_auth_methods_names[i].len == 0) { continue; } if (m & conf->auth_methods) { p = ngx_cpymem(p, ngx_mail_pop3_auth_methods_names[i].data, ngx_mail_pop3_auth_methods_names[i].len); *p++ = CR; *p++ = LF; } } *p++ = '.'; *p++ = CR; *p = LF; p = ngx_pnalloc(cf->pool, stls_only_size); if (p == NULL) { return NGX_CONF_ERROR; } conf->starttls_only_capability.len = stls_only_size; conf->starttls_only_capability.data = p; p = ngx_cpymem(p, "+OK Capability list follows" CRLF, sizeof("+OK Capability list follows" CRLF) - 1); for (i = 0; i < conf->capabilities.nelts; i++) { if (ngx_strcasecmp(c[i].data, (u_char *) "USER") == 0) { continue; } p = ngx_cpymem(p, c[i].data, c[i].len); *p++ = CR; *p++ = LF; } p = ngx_cpymem(p, "STLS" CRLF, sizeof("STLS" CRLF) - 1); *p++ = '.'; *p++ = CR; *p = LF; return NGX_CONF_OK; }