Mercurial > hg > nginx
view src/stream/ngx_stream_script.c @ 7098:7bfbf73db920
Stream: relaxed next upstream condition (ticket #1317).
When switching to a next upstream, some buffers could be stuck in the middle
of the filter chain. A condition existed that raised an error when this
happened. As it turned out, this condition prevented switching to a next
upstream if ssl preread was used with the TCP protocol (see the ticket).
In fact, the condition does not make sense for TCP, since after successful
connection to an upstream switching to another upstream never happens. As for
UDP, the issue with stuck buffers is unlikely to happen, but is still possible.
Specifically, if a filter delays sending data to upstream.
The condition can be relaxed to only check the "buffered" bitmask of the
upstream connection. The new condition is simpler and fixes the ticket issue
as well. Additionally, the upstream_out chain is now reset for UDP prior to
connecting to a new upstream to prevent repeating the client data twice.
author | Roman Arutyunyan <arut@nginx.com> |
---|---|
date | Mon, 11 Sep 2017 15:32:31 +0300 |
parents | 39ff6939266e |
children | 9e25a5380a21 |
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/* * Copyright (C) Igor Sysoev * Copyright (C) Nginx, Inc. */ #include <ngx_config.h> #include <ngx_core.h> #include <ngx_stream.h> static ngx_int_t ngx_stream_script_init_arrays( ngx_stream_script_compile_t *sc); static ngx_int_t ngx_stream_script_done(ngx_stream_script_compile_t *sc); static ngx_int_t ngx_stream_script_add_copy_code( ngx_stream_script_compile_t *sc, ngx_str_t *value, ngx_uint_t last); static ngx_int_t ngx_stream_script_add_var_code( ngx_stream_script_compile_t *sc, ngx_str_t *name); #if (NGX_PCRE) static ngx_int_t ngx_stream_script_add_capture_code( ngx_stream_script_compile_t *sc, ngx_uint_t n); #endif static ngx_int_t ngx_stream_script_add_full_name_code( ngx_stream_script_compile_t *sc); static size_t ngx_stream_script_full_name_len_code( ngx_stream_script_engine_t *e); static void ngx_stream_script_full_name_code(ngx_stream_script_engine_t *e); #define ngx_stream_script_exit (u_char *) &ngx_stream_script_exit_code static uintptr_t ngx_stream_script_exit_code = (uintptr_t) NULL; void ngx_stream_script_flush_complex_value(ngx_stream_session_t *s, ngx_stream_complex_value_t *val) { ngx_uint_t *index; index = val->flushes; if (index) { while (*index != (ngx_uint_t) -1) { if (s->variables[*index].no_cacheable) { s->variables[*index].valid = 0; s->variables[*index].not_found = 0; } index++; } } } ngx_int_t ngx_stream_complex_value(ngx_stream_session_t *s, ngx_stream_complex_value_t *val, ngx_str_t *value) { size_t len; ngx_stream_script_code_pt code; ngx_stream_script_engine_t e; ngx_stream_script_len_code_pt lcode; if (val->lengths == NULL) { *value = val->value; return NGX_OK; } ngx_stream_script_flush_complex_value(s, val); ngx_memzero(&e, sizeof(ngx_stream_script_engine_t)); e.ip = val->lengths; e.session = s; e.flushed = 1; len = 0; while (*(uintptr_t *) e.ip) { lcode = *(ngx_stream_script_len_code_pt *) e.ip; len += lcode(&e); } value->len = len; value->data = ngx_pnalloc(s->connection->pool, len); if (value->data == NULL) { return NGX_ERROR; } e.ip = val->values; e.pos = value->data; e.buf = *value; while (*(uintptr_t *) e.ip) { code = *(ngx_stream_script_code_pt *) e.ip; code((ngx_stream_script_engine_t *) &e); } *value = e.buf; return NGX_OK; } ngx_int_t ngx_stream_compile_complex_value(ngx_stream_compile_complex_value_t *ccv) { ngx_str_t *v; ngx_uint_t i, n, nv, nc; ngx_array_t flushes, lengths, values, *pf, *pl, *pv; ngx_stream_script_compile_t sc; v = ccv->value; nv = 0; nc = 0; for (i = 0; i < v->len; i++) { if (v->data[i] == '$') { if (v->data[i + 1] >= '1' && v->data[i + 1] <= '9') { nc++; } else { nv++; } } } if ((v->len == 0 || v->data[0] != '$') && (ccv->conf_prefix || ccv->root_prefix)) { if (ngx_conf_full_name(ccv->cf->cycle, v, ccv->conf_prefix) != NGX_OK) { return NGX_ERROR; } ccv->conf_prefix = 0; ccv->root_prefix = 0; } ccv->complex_value->value = *v; ccv->complex_value->flushes = NULL; ccv->complex_value->lengths = NULL; ccv->complex_value->values = NULL; if (nv == 0 && nc == 0) { return NGX_OK; } n = nv + 1; if (ngx_array_init(&flushes, ccv->cf->pool, n, sizeof(ngx_uint_t)) != NGX_OK) { return NGX_ERROR; } n = nv * (2 * sizeof(ngx_stream_script_copy_code_t) + sizeof(ngx_stream_script_var_code_t)) + sizeof(uintptr_t); if (ngx_array_init(&lengths, ccv->cf->pool, n, 1) != NGX_OK) { return NGX_ERROR; } n = (nv * (2 * sizeof(ngx_stream_script_copy_code_t) + sizeof(ngx_stream_script_var_code_t)) + sizeof(uintptr_t) + v->len + sizeof(uintptr_t) - 1) & ~(sizeof(uintptr_t) - 1); if (ngx_array_init(&values, ccv->cf->pool, n, 1) != NGX_OK) { return NGX_ERROR; } pf = &flushes; pl = &lengths; pv = &values; ngx_memzero(&sc, sizeof(ngx_stream_script_compile_t)); sc.cf = ccv->cf; sc.source = v; sc.flushes = &pf; sc.lengths = &pl; sc.values = &pv; sc.complete_lengths = 1; sc.complete_values = 1; sc.zero = ccv->zero; sc.conf_prefix = ccv->conf_prefix; sc.root_prefix = ccv->root_prefix; if (ngx_stream_script_compile(&sc) != NGX_OK) { return NGX_ERROR; } if (flushes.nelts) { ccv->complex_value->flushes = flushes.elts; ccv->complex_value->flushes[flushes.nelts] = (ngx_uint_t) -1; } ccv->complex_value->lengths = lengths.elts; ccv->complex_value->values = values.elts; return NGX_OK; } char * ngx_stream_set_complex_value_slot(ngx_conf_t *cf, ngx_command_t *cmd, void *conf) { char *p = conf; ngx_str_t *value; ngx_stream_complex_value_t **cv; ngx_stream_compile_complex_value_t ccv; cv = (ngx_stream_complex_value_t **) (p + cmd->offset); if (*cv != NULL) { return "is duplicate"; } *cv = ngx_palloc(cf->pool, sizeof(ngx_stream_complex_value_t)); if (*cv == NULL) { return NGX_CONF_ERROR; } value = cf->args->elts; ngx_memzero(&ccv, sizeof(ngx_stream_compile_complex_value_t)); ccv.cf = cf; ccv.value = &value[1]; ccv.complex_value = *cv; if (ngx_stream_compile_complex_value(&ccv) != NGX_OK) { return NGX_CONF_ERROR; } return NGX_CONF_OK; } ngx_uint_t ngx_stream_script_variables_count(ngx_str_t *value) { ngx_uint_t i, n; for (n = 0, i = 0; i < value->len; i++) { if (value->data[i] == '$') { n++; } } return n; } ngx_int_t ngx_stream_script_compile(ngx_stream_script_compile_t *sc) { u_char ch; ngx_str_t name; ngx_uint_t i, bracket; if (ngx_stream_script_init_arrays(sc) != NGX_OK) { return NGX_ERROR; } for (i = 0; i < sc->source->len; /* void */ ) { name.len = 0; if (sc->source->data[i] == '$') { if (++i == sc->source->len) { goto invalid_variable; } if (sc->source->data[i] >= '1' && sc->source->data[i] <= '9') { #if (NGX_PCRE) ngx_uint_t n; n = sc->source->data[i] - '0'; if (ngx_stream_script_add_capture_code(sc, n) != NGX_OK) { return NGX_ERROR; } i++; continue; #else ngx_conf_log_error(NGX_LOG_EMERG, sc->cf, 0, "using variable \"$%c\" requires " "PCRE library", sc->source->data[i]); return NGX_ERROR; #endif } if (sc->source->data[i] == '{') { bracket = 1; if (++i == sc->source->len) { goto invalid_variable; } name.data = &sc->source->data[i]; } else { bracket = 0; name.data = &sc->source->data[i]; } for ( /* void */ ; i < sc->source->len; i++, name.len++) { ch = sc->source->data[i]; if (ch == '}' && bracket) { i++; bracket = 0; break; } if ((ch >= 'A' && ch <= 'Z') || (ch >= 'a' && ch <= 'z') || (ch >= '0' && ch <= '9') || ch == '_') { continue; } break; } if (bracket) { ngx_conf_log_error(NGX_LOG_EMERG, sc->cf, 0, "the closing bracket in \"%V\" " "variable is missing", &name); return NGX_ERROR; } if (name.len == 0) { goto invalid_variable; } sc->variables++; if (ngx_stream_script_add_var_code(sc, &name) != NGX_OK) { return NGX_ERROR; } continue; } name.data = &sc->source->data[i]; while (i < sc->source->len) { if (sc->source->data[i] == '$') { break; } i++; name.len++; } sc->size += name.len; if (ngx_stream_script_add_copy_code(sc, &name, (i == sc->source->len)) != NGX_OK) { return NGX_ERROR; } } return ngx_stream_script_done(sc); invalid_variable: ngx_conf_log_error(NGX_LOG_EMERG, sc->cf, 0, "invalid variable name"); return NGX_ERROR; } u_char * ngx_stream_script_run(ngx_stream_session_t *s, ngx_str_t *value, void *code_lengths, size_t len, void *code_values) { ngx_uint_t i; ngx_stream_script_code_pt code; ngx_stream_script_engine_t e; ngx_stream_core_main_conf_t *cmcf; ngx_stream_script_len_code_pt lcode; cmcf = ngx_stream_get_module_main_conf(s, ngx_stream_core_module); for (i = 0; i < cmcf->variables.nelts; i++) { if (s->variables[i].no_cacheable) { s->variables[i].valid = 0; s->variables[i].not_found = 0; } } ngx_memzero(&e, sizeof(ngx_stream_script_engine_t)); e.ip = code_lengths; e.session = s; e.flushed = 1; while (*(uintptr_t *) e.ip) { lcode = *(ngx_stream_script_len_code_pt *) e.ip; len += lcode(&e); } value->len = len; value->data = ngx_pnalloc(s->connection->pool, len); if (value->data == NULL) { return NULL; } e.ip = code_values; e.pos = value->data; while (*(uintptr_t *) e.ip) { code = *(ngx_stream_script_code_pt *) e.ip; code((ngx_stream_script_engine_t *) &e); } return e.pos; } void ngx_stream_script_flush_no_cacheable_variables(ngx_stream_session_t *s, ngx_array_t *indices) { ngx_uint_t n, *index; if (indices) { index = indices->elts; for (n = 0; n < indices->nelts; n++) { if (s->variables[index[n]].no_cacheable) { s->variables[index[n]].valid = 0; s->variables[index[n]].not_found = 0; } } } } static ngx_int_t ngx_stream_script_init_arrays(ngx_stream_script_compile_t *sc) { ngx_uint_t n; if (sc->flushes && *sc->flushes == NULL) { n = sc->variables ? sc->variables : 1; *sc->flushes = ngx_array_create(sc->cf->pool, n, sizeof(ngx_uint_t)); if (*sc->flushes == NULL) { return NGX_ERROR; } } if (*sc->lengths == NULL) { n = sc->variables * (2 * sizeof(ngx_stream_script_copy_code_t) + sizeof(ngx_stream_script_var_code_t)) + sizeof(uintptr_t); *sc->lengths = ngx_array_create(sc->cf->pool, n, 1); if (*sc->lengths == NULL) { return NGX_ERROR; } } if (*sc->values == NULL) { n = (sc->variables * (2 * sizeof(ngx_stream_script_copy_code_t) + sizeof(ngx_stream_script_var_code_t)) + sizeof(uintptr_t) + sc->source->len + sizeof(uintptr_t) - 1) & ~(sizeof(uintptr_t) - 1); *sc->values = ngx_array_create(sc->cf->pool, n, 1); if (*sc->values == NULL) { return NGX_ERROR; } } sc->variables = 0; return NGX_OK; } static ngx_int_t ngx_stream_script_done(ngx_stream_script_compile_t *sc) { ngx_str_t zero; uintptr_t *code; if (sc->zero) { zero.len = 1; zero.data = (u_char *) "\0"; if (ngx_stream_script_add_copy_code(sc, &zero, 0) != NGX_OK) { return NGX_ERROR; } } if (sc->conf_prefix || sc->root_prefix) { if (ngx_stream_script_add_full_name_code(sc) != NGX_OK) { return NGX_ERROR; } } if (sc->complete_lengths) { code = ngx_stream_script_add_code(*sc->lengths, sizeof(uintptr_t), NULL); if (code == NULL) { return NGX_ERROR; } *code = (uintptr_t) NULL; } if (sc->complete_values) { code = ngx_stream_script_add_code(*sc->values, sizeof(uintptr_t), &sc->main); if (code == NULL) { return NGX_ERROR; } *code = (uintptr_t) NULL; } return NGX_OK; } void * ngx_stream_script_add_code(ngx_array_t *codes, size_t size, void *code) { u_char *elts, **p; void *new; elts = codes->elts; new = ngx_array_push_n(codes, size); if (new == NULL) { return NULL; } if (code) { if (elts != codes->elts) { p = code; *p += (u_char *) codes->elts - elts; } } return new; } static ngx_int_t ngx_stream_script_add_copy_code(ngx_stream_script_compile_t *sc, ngx_str_t *value, ngx_uint_t last) { u_char *p; size_t size, len, zero; ngx_stream_script_copy_code_t *code; zero = (sc->zero && last); len = value->len + zero; code = ngx_stream_script_add_code(*sc->lengths, sizeof(ngx_stream_script_copy_code_t), NULL); if (code == NULL) { return NGX_ERROR; } code->code = (ngx_stream_script_code_pt) ngx_stream_script_copy_len_code; code->len = len; size = (sizeof(ngx_stream_script_copy_code_t) + len + sizeof(uintptr_t) - 1) & ~(sizeof(uintptr_t) - 1); code = ngx_stream_script_add_code(*sc->values, size, &sc->main); if (code == NULL) { return NGX_ERROR; } code->code = ngx_stream_script_copy_code; code->len = len; p = ngx_cpymem((u_char *) code + sizeof(ngx_stream_script_copy_code_t), value->data, value->len); if (zero) { *p = '\0'; sc->zero = 0; } return NGX_OK; } size_t ngx_stream_script_copy_len_code(ngx_stream_script_engine_t *e) { ngx_stream_script_copy_code_t *code; code = (ngx_stream_script_copy_code_t *) e->ip; e->ip += sizeof(ngx_stream_script_copy_code_t); return code->len; } void ngx_stream_script_copy_code(ngx_stream_script_engine_t *e) { u_char *p; ngx_stream_script_copy_code_t *code; code = (ngx_stream_script_copy_code_t *) e->ip; p = e->pos; if (!e->skip) { e->pos = ngx_copy(p, e->ip + sizeof(ngx_stream_script_copy_code_t), code->len); } e->ip += sizeof(ngx_stream_script_copy_code_t) + ((code->len + sizeof(uintptr_t) - 1) & ~(sizeof(uintptr_t) - 1)); ngx_log_debug2(NGX_LOG_DEBUG_STREAM, e->session->connection->log, 0, "stream script copy: \"%*s\"", e->pos - p, p); } static ngx_int_t ngx_stream_script_add_var_code(ngx_stream_script_compile_t *sc, ngx_str_t *name) { ngx_int_t index, *p; ngx_stream_script_var_code_t *code; index = ngx_stream_get_variable_index(sc->cf, name); if (index == NGX_ERROR) { return NGX_ERROR; } if (sc->flushes) { p = ngx_array_push(*sc->flushes); if (p == NULL) { return NGX_ERROR; } *p = index; } code = ngx_stream_script_add_code(*sc->lengths, sizeof(ngx_stream_script_var_code_t), NULL); if (code == NULL) { return NGX_ERROR; } code->code = (ngx_stream_script_code_pt) ngx_stream_script_copy_var_len_code; code->index = (uintptr_t) index; code = ngx_stream_script_add_code(*sc->values, sizeof(ngx_stream_script_var_code_t), &sc->main); if (code == NULL) { return NGX_ERROR; } code->code = ngx_stream_script_copy_var_code; code->index = (uintptr_t) index; return NGX_OK; } size_t ngx_stream_script_copy_var_len_code(ngx_stream_script_engine_t *e) { ngx_stream_variable_value_t *value; ngx_stream_script_var_code_t *code; code = (ngx_stream_script_var_code_t *) e->ip; e->ip += sizeof(ngx_stream_script_var_code_t); if (e->flushed) { value = ngx_stream_get_indexed_variable(e->session, code->index); } else { value = ngx_stream_get_flushed_variable(e->session, code->index); } if (value && !value->not_found) { return value->len; } return 0; } void ngx_stream_script_copy_var_code(ngx_stream_script_engine_t *e) { u_char *p; ngx_stream_variable_value_t *value; ngx_stream_script_var_code_t *code; code = (ngx_stream_script_var_code_t *) e->ip; e->ip += sizeof(ngx_stream_script_var_code_t); if (!e->skip) { if (e->flushed) { value = ngx_stream_get_indexed_variable(e->session, code->index); } else { value = ngx_stream_get_flushed_variable(e->session, code->index); } if (value && !value->not_found) { p = e->pos; e->pos = ngx_copy(p, value->data, value->len); ngx_log_debug2(NGX_LOG_DEBUG_STREAM, e->session->connection->log, 0, "stream script var: \"%*s\"", e->pos - p, p); } } } #if (NGX_PCRE) static ngx_int_t ngx_stream_script_add_capture_code(ngx_stream_script_compile_t *sc, ngx_uint_t n) { ngx_stream_script_copy_capture_code_t *code; code = ngx_stream_script_add_code(*sc->lengths, sizeof(ngx_stream_script_copy_capture_code_t), NULL); if (code == NULL) { return NGX_ERROR; } code->code = (ngx_stream_script_code_pt) ngx_stream_script_copy_capture_len_code; code->n = 2 * n; code = ngx_stream_script_add_code(*sc->values, sizeof(ngx_stream_script_copy_capture_code_t), &sc->main); if (code == NULL) { return NGX_ERROR; } code->code = ngx_stream_script_copy_capture_code; code->n = 2 * n; if (sc->ncaptures < n) { sc->ncaptures = n; } return NGX_OK; } size_t ngx_stream_script_copy_capture_len_code(ngx_stream_script_engine_t *e) { int *cap; ngx_uint_t n; ngx_stream_session_t *s; ngx_stream_script_copy_capture_code_t *code; s = e->session; code = (ngx_stream_script_copy_capture_code_t *) e->ip; e->ip += sizeof(ngx_stream_script_copy_capture_code_t); n = code->n; if (n < s->ncaptures) { cap = s->captures; return cap[n + 1] - cap[n]; } return 0; } void ngx_stream_script_copy_capture_code(ngx_stream_script_engine_t *e) { int *cap; u_char *p, *pos; ngx_uint_t n; ngx_stream_session_t *s; ngx_stream_script_copy_capture_code_t *code; s = e->session; code = (ngx_stream_script_copy_capture_code_t *) e->ip; e->ip += sizeof(ngx_stream_script_copy_capture_code_t); n = code->n; pos = e->pos; if (n < s->ncaptures) { cap = s->captures; p = s->captures_data; e->pos = ngx_copy(pos, &p[cap[n]], cap[n + 1] - cap[n]); } ngx_log_debug2(NGX_LOG_DEBUG_STREAM, e->session->connection->log, 0, "stream script capture: \"%*s\"", e->pos - pos, pos); } #endif static ngx_int_t ngx_stream_script_add_full_name_code(ngx_stream_script_compile_t *sc) { ngx_stream_script_full_name_code_t *code; code = ngx_stream_script_add_code(*sc->lengths, sizeof(ngx_stream_script_full_name_code_t), NULL); if (code == NULL) { return NGX_ERROR; } code->code = (ngx_stream_script_code_pt) ngx_stream_script_full_name_len_code; code->conf_prefix = sc->conf_prefix; code = ngx_stream_script_add_code(*sc->values, sizeof(ngx_stream_script_full_name_code_t), &sc->main); if (code == NULL) { return NGX_ERROR; } code->code = ngx_stream_script_full_name_code; code->conf_prefix = sc->conf_prefix; return NGX_OK; } static size_t ngx_stream_script_full_name_len_code(ngx_stream_script_engine_t *e) { ngx_stream_script_full_name_code_t *code; code = (ngx_stream_script_full_name_code_t *) e->ip; e->ip += sizeof(ngx_stream_script_full_name_code_t); return code->conf_prefix ? ngx_cycle->conf_prefix.len: ngx_cycle->prefix.len; } static void ngx_stream_script_full_name_code(ngx_stream_script_engine_t *e) { ngx_stream_script_full_name_code_t *code; ngx_str_t value, *prefix; code = (ngx_stream_script_full_name_code_t *) e->ip; value.data = e->buf.data; value.len = e->pos - e->buf.data; prefix = code->conf_prefix ? (ngx_str_t *) &ngx_cycle->conf_prefix: (ngx_str_t *) &ngx_cycle->prefix; if (ngx_get_full_name(e->session->connection->pool, prefix, &value) != NGX_OK) { e->ip = ngx_stream_script_exit; return; } e->buf = value; ngx_log_debug1(NGX_LOG_DEBUG_STREAM, e->session->connection->log, 0, "stream script fullname: \"%V\"", &value); e->ip += sizeof(ngx_stream_script_full_name_code_t); }