ngx_http_proxy_module.c

Nginx ("engine x") 是一个高性能的 HTTP 和 反向代理 服务器

        if (conf->upstream.pass_headers == NULL) {
            conf->upstream.pass_headers = prev->upstream.pass_headers;
        }
    }

    if (ngx_array_init(&hide_headers, cf->temp_pool, 4, sizeof(ngx_hash_key_t))
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    for (header = ngx_http_proxy_hide_headers; header->len; header++) {
        hk = ngx_array_push(&hide_headers);
        if (hk == NULL) {
            return NGX_CONF_ERROR;
        }

        hk->key = *header;
        hk->key_hash = ngx_hash_key_lc(header->data, header->len);
        hk->value = (void *) 1;
    }

    if (conf->upstream.hide_headers) {

        header = conf->upstream.hide_headers->elts;

        for (i = 0; i < conf->upstream.hide_headers->nelts; i++) {

            hk = hide_headers.elts;

            for (j = 0; j < hide_headers.nelts; j++) {
                if (ngx_strcasecmp(header[i].data, hk[j].key.data) == 0) {
                    goto exist;
                }
            }

            hk = ngx_array_push(&hide_headers);
            if (hk == NULL) {
                return NGX_CONF_ERROR;
            }

            hk->key = header[i];
            hk->key_hash = ngx_hash_key_lc(header[i].data, header[i].len);
            hk->value = (void *) 1;

        exist:

            continue;
        }
    }

    if (conf->upstream.pass_headers) {

        hk = hide_headers.elts;
        header = conf->upstream.pass_headers->elts;

        for (i = 0; i < conf->upstream.pass_headers->nelts; i++) {
            for (j = 0; j < hide_headers.nelts; j++) {

                if (hk[j].key.data == NULL) {
                    continue;
                }

                if (ngx_strcasecmp(header[i].data, hk[j].key.data) == 0) {
                    hk[j].key.data = NULL;
                    break;
                }
            }
        }
    }

    hash.hash = &conf->upstream.hide_headers_hash;
    hash.key = ngx_hash_key_lc;
    hash.max_size = conf->headers_hash_max_size;
    hash.bucket_size = conf->headers_hash_bucket_size;
    hash.name = "proxy_headers_hash";
    hash.pool = cf->pool;
    hash.temp_pool = NULL;

    if (ngx_hash_init(&hash, hide_headers.elts, hide_headers.nelts) != NGX_OK) {
        return NGX_CONF_ERROR;
    }

peers:

    if (conf->upstream.upstream == NULL) {
        conf->upstream.upstream = prev->upstream.upstream;

        conf->host_header = prev->host_header;
        conf->port = prev->port;
        conf->upstream.schema = prev->upstream.schema;
    }


    if (conf->body_source.data == NULL) {
        conf->body_source = prev->body_source;
        conf->body_set_len = prev->body_set_len;
        conf->body_set = prev->body_set;
    }

    if (conf->body_source.data && conf->body_set_len == NULL) {

        ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));

        sc.cf = cf;
        sc.source = &conf->body_source;
        sc.flushes = &conf->flushes;
        sc.lengths = &conf->body_set_len;
        sc.values = &conf->body_set;
        sc.complete_lengths = 1;
        sc.complete_values = 1;

        if (ngx_http_script_compile(&sc) != NGX_OK) {
            return NGX_CONF_ERROR;
        }

        if (conf->headers_source == NULL) {
            conf->headers_source = ngx_array_create(cf->pool, 4,
                                                    sizeof(ngx_keyval_t));
            if (conf->headers_source == NULL) {
                return NGX_CONF_ERROR;
            }
        }

        s = ngx_array_push(conf->headers_source);
        if (s == NULL) {
            return NGX_CONF_ERROR;
        }

        s->key.len = sizeof("Content-Length") - 1;
        s->key.data = (u_char *) "Content-Length";
        s->value.len = sizeof("$proxy_internal_body_length") - 1;
        s->value.data = (u_char *) "$proxy_internal_body_length";
    }


    if (conf->headers_source == NULL) {
        conf->flushes = prev->flushes;
        conf->headers_set_len = prev->headers_set_len;
        conf->headers_set = prev->headers_set;
        conf->headers_set_hash = prev->headers_set_hash;
        conf->headers_source = prev->headers_source;
    }

    if (conf->headers_set_hash.buckets) {
        return NGX_CONF_OK;
    }


    conf->headers_names = ngx_array_create(cf->pool, 4, sizeof(ngx_hash_key_t));
    if (conf->headers_names == NULL) {
        return NGX_CONF_ERROR;
    }

    if (conf->headers_source == NULL) {
        conf->headers_source = ngx_array_create(cf->pool, 4,
                                                sizeof(ngx_keyval_t));
        if (conf->headers_source == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    conf->headers_set_len = ngx_array_create(cf->pool, 64, 1);
    if (conf->headers_set_len == NULL) {
        return NGX_CONF_ERROR;
    }

    conf->headers_set = ngx_array_create(cf->pool, 512, 1);
    if (conf->headers_set == NULL) {
        return NGX_CONF_ERROR;
    }


    src = conf->headers_source->elts;

    for (h = ngx_http_proxy_headers; h->key.len; h++) {

        for (i = 0; i < conf->headers_source->nelts; i++) {
            if (ngx_strcasecmp(h->key.data, src[i].key.data) == 0) {
                goto next;
            }
        }

        s = ngx_array_push(conf->headers_source);
        if (s == NULL) {
            return NGX_CONF_ERROR;
        }

        *s = *h;

        src = conf->headers_source->elts;

    next:

        continue;
    }


    src = conf->headers_source->elts;
    for (i = 0; i < conf->headers_source->nelts; i++) {

        hk = ngx_array_push(conf->headers_names);
        if (hk == NULL) {
            return NGX_CONF_ERROR;
        }

        hk->key = src[i].key;
        hk->key_hash = ngx_hash_key_lc(src[i].key.data, src[i].key.len);
        hk->value = (void *) 1;

        if (src[i].value.len == 0) {
            continue;
        }

        if (ngx_http_script_variables_count(&src[i].value) == 0) {
            copy = ngx_array_push_n(conf->headers_set_len,
                                    sizeof(ngx_http_script_copy_code_t));
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = (ngx_http_script_code_pt)
                                                 ngx_http_script_copy_len_code;
            copy->len = src[i].key.len + sizeof(": ") - 1
                        + src[i].value.len + sizeof(CRLF) - 1;


            size = (sizeof(ngx_http_script_copy_code_t)
                       + src[i].key.len + sizeof(": ") - 1
                       + src[i].value.len + sizeof(CRLF) - 1
                       + sizeof(uintptr_t) - 1)
                    & ~(sizeof(uintptr_t) - 1);

            copy = ngx_array_push_n(conf->headers_set, size);
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = ngx_http_script_copy_code;
            copy->len = src[i].key.len + sizeof(": ") - 1
                        + src[i].value.len + sizeof(CRLF) - 1;

            p = (u_char *) copy + sizeof(ngx_http_script_copy_code_t);

            p = ngx_cpymem(p, src[i].key.data, src[i].key.len);
            *p++ = ':'; *p++ = ' ';
            p = ngx_cpymem(p, src[i].value.data, src[i].value.len);
            *p++ = CR; *p = LF;

        } else {
            copy = ngx_array_push_n(conf->headers_set_len,
                                    sizeof(ngx_http_script_copy_code_t));
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = (ngx_http_script_code_pt)
                                                 ngx_http_script_copy_len_code;
            copy->len = src[i].key.len + sizeof(": ") - 1;


            size = (sizeof(ngx_http_script_copy_code_t)
                    + src[i].key.len + sizeof(": ") - 1 + sizeof(uintptr_t) - 1)
                    & ~(sizeof(uintptr_t) - 1);

            copy = ngx_array_push_n(conf->headers_set, size);
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = ngx_http_script_copy_code;
            copy->len = src[i].key.len + sizeof(": ") - 1;

            p = (u_char *) copy + sizeof(ngx_http_script_copy_code_t);
            p = ngx_cpymem(p, src[i].key.data, src[i].key.len);
            *p++ = ':'; *p = ' ';


            ngx_memzero(&sc, sizeof(ngx_http_script_compile_t));

            sc.cf = cf;
            sc.source = &src[i].value;
            sc.flushes = &conf->flushes;
            sc.lengths = &conf->headers_set_len;
            sc.values = &conf->headers_set;

            if (ngx_http_script_compile(&sc) != NGX_OK) {
                return NGX_CONF_ERROR;
            }


            copy = ngx_array_push_n(conf->headers_set_len,
                                    sizeof(ngx_http_script_copy_code_t));
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = (ngx_http_script_code_pt)
                                                 ngx_http_script_copy_len_code;
            copy->len = sizeof(CRLF) - 1;


            size = (sizeof(ngx_http_script_copy_code_t)
                    + sizeof(CRLF) - 1 + sizeof(uintptr_t) - 1)
                    & ~(sizeof(uintptr_t) - 1);

            copy = ngx_array_push_n(conf->headers_set, size);
            if (copy == NULL) {
                return NGX_CONF_ERROR;
            }

            copy->code = ngx_http_script_copy_code;
            copy->len = sizeof(CRLF) - 1;

            p = (u_char *) copy + sizeof(ngx_http_script_copy_code_t);
            *p++ = CR; *p = LF;
        }

        code = ngx_array_push_n(conf->headers_set_len, sizeof(uintptr_t));
        if (code == NULL) {
            return NGX_CONF_ERROR;
        }

        *code = (uintptr_t) NULL;

        code = ngx_array_push_n(conf->headers_set, sizeof(uintptr_t));
        if (code == NULL) {
            return NGX_CONF_ERROR;
        }

        *code = (uintptr_t) NULL;
    }

    code = ngx_array_push_n(conf->headers_set_len, sizeof(uintptr_t));
    if (code == NULL) {
        return NGX_CONF_ERROR;
    }

    *code = (uintptr_t) NULL;


    hash.hash = &conf->headers_set_hash;
    hash.key = ngx_hash_key_lc;
    hash.max_size = conf->headers_hash_max_size;
    hash.bucket_size = conf->headers_hash_bucket_size;
    hash.name = "proxy_headers_hash";
    hash.pool = cf->pool;
    hash.temp_pool = NULL;

    if (ngx_hash_init(&hash, conf->headers_names->elts,
                      conf->headers_names->nelts)
        != NGX_OK)
    {
        return NGX_CONF_ERROR;
    }

    return NGX_CONF_OK;
}


static char *
ngx_http_proxy_pass(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_http_proxy_loc_conf_t *plcf = conf;

    u_char                    *p;
    size_t                     add;
    u_short                    port;
    ngx_str_t                 *value, *url;
    ngx_url_t                  u;
    ngx_http_core_loc_conf_t  *clcf;
#if (NGX_HTTP_SSL)
    ngx_pool_cleanup_t        *cln;
#endif

    if (plcf->upstream.schema.len) {
        return "is duplicate";
    }

    value = cf->args->elts;

    url = &value[1];

    if (ngx_strncasecmp(url->data, (u_char *) "http://", 7) == 0) {
        add = 7;
        port = 80;

    } else if (ngx_strncasecmp(url->data, (u_char *) "https://", 8) == 0) {

#if (NGX_HTTP_SSL)

        add = 8;
        port = 443;

        plcf->upstream.ssl = ngx_pcalloc(cf->pool, sizeof(ngx_ssl_t));
        if (plcf->upstream.ssl == NULL) {
            return NGX_CONF_ERROR;
        }

        plcf->upstream.ssl->log = cf->log;

        if (ngx_ssl_create(plcf->upstream.ssl,
                           NGX_SSL_SSLv2|NGX_SSL_SSLv3|NGX_SSL_TLSv1, NULL)
            != NGX_OK)
        {
            return NGX_CONF_ERROR;
        }

        cln = ngx_pool_cleanup_add(cf->pool, 0);
        if (cln == NULL) {
            return NGX_CONF_ERROR;
        }

        cln->handler = ngx_ssl_cleanup_ctx;
        cln->data = plcf->upstream.ssl;

#else
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                           "https protocol requires SSL support");
        return NGX_CONF_ERROR;
#endif

    } else {
        ngx_conf_log_error(NGX_LOG_EMERG, cf, 0, "invalid URL prefix");
        return NGX_CONF_ERROR;
    }

    ngx_memzero(&u, sizeof(ngx_url_t));

    u.url.len = url->len - add;
    u.url.data = url->data + add;
    u.default_port = port;
    u.uri_part = 1;
    u.no_resolve = 1;

    plcf->upstream.upstream = ngx_http_upstream_add(cf, &u, 0);
    if (plcf->upstream.upstream == NULL) {
        return NGX_CONF_ERROR;
    }

    if (!u.unix_socket) {
        if (u.no_port || u.port == port) {
            plcf->host_header = u.host;

            if (port == 80) {