ngx_mail_auth_http_module.c

Nginx是一个高性能的HTTP和反向代理服务器

                c = (u_char) (ch | 0x20);
                if (c >= 'a' && c <= 'z') {
                    hash = c;
                    break;
                }

                if (ch >= '0' && ch <= '9') {
                    hash = ch;
                    break;
                }

                return NGX_ERROR;
            }
            break;

        /* header name */
        case sw_name:
            c = (u_char) (ch | 0x20);
            if (c >= 'a' && c <= 'z') {
                hash += c;
                break;
            }

            if (ch == ':') {
                ctx->header_name_end = p;
                state = sw_space_before_value;
                break;
            }

            if (ch == '-') {
                hash += ch;
                break;
            }

            if (ch >= '0' && ch <= '9') {
                hash += ch;
                break;
            }

            if (ch == CR) {
                ctx->header_name_end = p;
                ctx->header_start = p;
                ctx->header_end = p;
                state = sw_almost_done;
                break;
            }

            if (ch == LF) {
                ctx->header_name_end = p;
                ctx->header_start = p;
                ctx->header_end = p;
                goto done;
            }

            return NGX_ERROR;

        /* space* before header value */
        case sw_space_before_value:
            switch (ch) {
            case ' ':
                break;
            case CR:
                ctx->header_start = p;
                ctx->header_end = p;
                state = sw_almost_done;
                break;
            case LF:
                ctx->header_start = p;
                ctx->header_end = p;
                goto done;
            default:
                ctx->header_start = p;
                state = sw_value;
                break;
            }
            break;

        /* header value */
        case sw_value:
            switch (ch) {
            case ' ':
                ctx->header_end = p;
                state = sw_space_after_value;
                break;
            case CR:
                ctx->header_end = p;
                state = sw_almost_done;
                break;
            case LF:
                ctx->header_end = p;
                goto done;
            }
            break;

        /* space* before end of header line */
        case sw_space_after_value:
            switch (ch) {
            case ' ':
                break;
            case CR:
                state = sw_almost_done;
                break;
            case LF:
                goto done;
            default:
                state = sw_value;
                break;
            }
            break;

        /* end of header line */
        case sw_almost_done:
            switch (ch) {
            case LF:
                goto done;
            default:
                return NGX_ERROR;
            }

        /* end of header */
        case sw_header_almost_done:
            switch (ch) {
            case LF:
                goto header_done;
            default:
                return NGX_ERROR;
            }
        }
    }

    ctx->response->pos = p;
    ctx->state = state;
    ctx->hash = hash;

    return NGX_AGAIN;

done:

    ctx->response->pos = p + 1;
    ctx->state = sw_start;
    ctx->hash = hash;

    return NGX_OK;

header_done:

    ctx->response->pos = p + 1;
    ctx->state = sw_start;

    return NGX_DONE;
}


static void
ngx_mail_auth_http_block_read(ngx_event_t *rev)
{
    ngx_connection_t          *c;
    ngx_mail_session_t        *s;
    ngx_mail_auth_http_ctx_t  *ctx;

    ngx_log_debug0(NGX_LOG_DEBUG_MAIL, rev->log, 0,
                   "mail auth http block read");

    if (ngx_handle_read_event(rev, 0) == NGX_ERROR) {
        c = rev->data;
        s = c->data;

        ctx = ngx_mail_get_module_ctx(s, ngx_mail_auth_http_module);

        ngx_close_connection(ctx->peer.connection);
        ngx_destroy_pool(ctx->pool);
        ngx_mail_session_internal_server_error(s);
    }
}


static void
ngx_mail_auth_http_dummy_handler(ngx_event_t *ev)
{
    ngx_log_debug0(NGX_LOG_DEBUG_MAIL, ev->log, 0,
                   "mail auth http dummy handler");
}


static ngx_buf_t *
ngx_mail_auth_http_create_request(ngx_mail_session_t *s, ngx_pool_t *pool,
    ngx_mail_auth_http_conf_t *ahcf)
{
    size_t                     len;
    ngx_buf_t                 *b;
    ngx_str_t                  login, passwd;
    ngx_mail_core_srv_conf_t  *cscf;

    if (ngx_mail_auth_http_escape(pool, &s->login, &login) != NGX_OK) {
        return NULL;
    }

    if (ngx_mail_auth_http_escape(pool, &s->passwd, &passwd) != NGX_OK) {
        return NULL;
    }

    cscf = ngx_mail_get_module_srv_conf(s, ngx_mail_core_module);

    len = sizeof("GET ") - 1 + ahcf->uri.len + sizeof(" HTTP/1.0" CRLF) - 1
          + sizeof("Host: ") - 1 + ahcf->host_header.len + sizeof(CRLF) - 1
          + sizeof("Auth-Method: ") - 1
                + ngx_mail_auth_http_method[s->auth_method].len
                + sizeof(CRLF) - 1
          + sizeof("Auth-User: ") - 1 + login.len + sizeof(CRLF) - 1
          + sizeof("Auth-Pass: ") - 1 + passwd.len + sizeof(CRLF) - 1
          + sizeof("Auth-Salt: ") - 1 + s->salt.len
          + sizeof("Auth-Protocol: ") - 1 + cscf->protocol->name.len
                + sizeof(CRLF) - 1
          + sizeof("Auth-Login-Attempt: ") - 1 + NGX_INT_T_LEN
                + sizeof(CRLF) - 1
          + sizeof("Client-IP: ") - 1 + s->connection->addr_text.len
                + sizeof(CRLF) - 1
          + ahcf->header.len
          + sizeof(CRLF) - 1;

    b = ngx_create_temp_buf(pool, len);
    if (b == NULL) {
        return NULL;
    }

    b->last = ngx_cpymem(b->last, "GET ", sizeof("GET ") - 1);
    b->last = ngx_copy(b->last, ahcf->uri.data, ahcf->uri.len);
    b->last = ngx_cpymem(b->last, " HTTP/1.0" CRLF,
                         sizeof(" HTTP/1.0" CRLF) - 1);

    b->last = ngx_cpymem(b->last, "Host: ", sizeof("Host: ") - 1);
    b->last = ngx_copy(b->last, ahcf->host_header.data,
                         ahcf->host_header.len);
    *b->last++ = CR; *b->last++ = LF;

    b->last = ngx_cpymem(b->last, "Auth-Method: ",
                         sizeof("Auth-Method: ") - 1);
    b->last = ngx_cpymem(b->last,
                         ngx_mail_auth_http_method[s->auth_method].data,
                         ngx_mail_auth_http_method[s->auth_method].len);
    *b->last++ = CR; *b->last++ = LF;

    b->last = ngx_cpymem(b->last, "Auth-User: ", sizeof("Auth-User: ") - 1);
    b->last = ngx_copy(b->last, login.data, login.len);
    *b->last++ = CR; *b->last++ = LF;

    b->last = ngx_cpymem(b->last, "Auth-Pass: ", sizeof("Auth-Pass: ") - 1);
    b->last = ngx_copy(b->last, passwd.data, passwd.len);
    *b->last++ = CR; *b->last++ = LF;

    if (s->auth_method != NGX_MAIL_AUTH_PLAIN && s->salt.len) {
        b->last = ngx_cpymem(b->last, "Auth-Salt: ", sizeof("Auth-Salt: ") - 1);
        b->last = ngx_copy(b->last, s->salt.data, s->salt.len);

        s->passwd.data = NULL;
    }

    b->last = ngx_cpymem(b->last, "Auth-Protocol: ",
                         sizeof("Auth-Protocol: ") - 1);
    b->last = ngx_cpymem(b->last, cscf->protocol->name.data,
                         cscf->protocol->name.len);
    *b->last++ = CR; *b->last++ = LF;

    b->last = ngx_sprintf(b->last, "Auth-Login-Attempt: %ui" CRLF,
                          s->login_attempt);

    b->last = ngx_cpymem(b->last, "Client-IP: ", sizeof("Client-IP: ") - 1);
    b->last = ngx_copy(b->last, s->connection->addr_text.data,
                         s->connection->addr_text.len);
    *b->last++ = CR; *b->last++ = LF;

    if (ahcf->header.len) {
        b->last = ngx_copy(b->last, ahcf->header.data, ahcf->header.len);
    }

    /* add "\r\n" at the header end */
    *b->last++ = CR; *b->last++ = LF;

#if (NGX_DEBUG_MAIL_PASSWD)
    {
    ngx_str_t  l;

    l.len = b->last - b->pos;
    l.data = b->pos;
    ngx_log_debug1(NGX_LOG_DEBUG_MAIL, s->connection->log, 0,
                   "mail auth http header:\n\"%V\"", &l);
    }
#endif

    return b;
}


static ngx_int_t
ngx_mail_auth_http_escape(ngx_pool_t *pool, ngx_str_t *text, ngx_str_t *escaped)
{
    u_char     *p;
    uintptr_t   n;

    n = ngx_escape_uri(NULL, text->data, text->len, NGX_ESCAPE_MAIL_AUTH);

    if (n == 0) {
        *escaped = *text;
        return NGX_OK;
    }

    escaped->len = text->len + n * 2;

    p = ngx_palloc(pool, escaped->len);
    if (p == NULL) {
        return NGX_ERROR;
    }

    (void) ngx_escape_uri(p, text->data, text->len, NGX_ESCAPE_MAIL_AUTH);

    escaped->data = p;

    return NGX_OK;
}


static void *
ngx_mail_auth_http_create_conf(ngx_conf_t *cf)
{
    ngx_mail_auth_http_conf_t  *ahcf;

    ahcf = ngx_pcalloc(cf->pool, sizeof(ngx_mail_auth_http_conf_t));
    if (ahcf == NULL) {
        return NGX_CONF_ERROR;
    }

    ahcf->timeout = NGX_CONF_UNSET_MSEC;

    ahcf->file = cf->conf_file->file.name.data;
    ahcf->line = cf->conf_file->line;

    return ahcf;
}


static char *
ngx_mail_auth_http_merge_conf(ngx_conf_t *cf, void *parent, void *child)
{
    ngx_mail_auth_http_conf_t *prev = parent;
    ngx_mail_auth_http_conf_t *conf = child;

    u_char           *p;
    size_t            len;
    ngx_uint_t        i;
    ngx_table_elt_t  *header;

    if (conf->peer == NULL) {
        conf->peer = prev->peer;
        conf->host_header = prev->host_header;
        conf->uri = prev->uri;

        if (conf->peer == NULL) {
            ngx_log_error(NGX_LOG_EMERG, cf->log, 0,
                          "no \"http_auth\" is defined for server in %s:%ui",
                          conf->file, conf->line);

            return NGX_CONF_ERROR;
        }
    }

    ngx_conf_merge_msec_value(conf->timeout, prev->timeout, 60000);

    if (conf->headers == NULL) {
        conf->headers = prev->headers;
        conf->header = prev->header;
    }

    if (conf->headers && conf->header.len == 0) {
        len = 0;
        header = conf->headers->elts;
        for (i = 0; i < conf->headers->nelts; i++) {
            len += header[i].key.len + 2 + header[i].value.len + 2;
        }

        p = ngx_palloc(cf->pool, len);
        if (p == NULL) {
            return NGX_CONF_ERROR;
        }

        conf->header.len = len;
        conf->header.data = p;

        for (i = 0; i < conf->headers->nelts; i++) {
            p = ngx_cpymem(p, header[i].key.data, header[i].key.len);
            *p++ = ':'; *p++ = ' ';
            p = ngx_cpymem(p, header[i].value.data, header[i].value.len);
            *p++ = CR; *p++ = LF;
        }
    }

    return NGX_CONF_OK;
}


static char *
ngx_mail_auth_http(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_mail_auth_http_conf_t *ahcf = conf;

    ngx_str_t  *value;
    ngx_url_t   u;

    value = cf->args->elts;

    ngx_memzero(&u, sizeof(ngx_url_t));

    u.url = value[1];
    u.default_port = 80;
    u.uri_part = 1;
    u.one_addr = 1;

    if (ngx_strncmp(u.url.data, "http://", 7) == 0) {
        u.url.len -= 7;
        u.url.data += 7;
    }

    if (ngx_parse_url(cf->pool, &u) != NGX_OK) {
        if (u.err) {
            ngx_conf_log_error(NGX_LOG_EMERG, cf, 0,
                               "%s in auth_http \"%V\"", u.err, &u.url);
        }

        return NGX_CONF_ERROR;
    }

    ahcf->peer = u.addrs;

    ahcf->host_header = u.host;
    ahcf->uri = u.uri;

    if (ahcf->uri.len == 0) {
        ahcf->uri.len = sizeof("/") - 1;
        ahcf->uri.data = (u_char *) "/";
    }

    return NGX_CONF_OK;
}


static char *
ngx_mail_auth_http_header(ngx_conf_t *cf, ngx_command_t *cmd, void *conf)
{
    ngx_mail_auth_http_conf_t *ahcf = conf;

    ngx_str_t        *value;
    ngx_table_elt_t  *header;

    if (ahcf->headers == NULL) {
        ahcf->headers = ngx_array_create(cf->pool, 1, sizeof(ngx_table_elt_t));
        if (ahcf->headers == NULL) {
            return NGX_CONF_ERROR;
        }
    }

    header = ngx_array_push(ahcf->headers);
    if (header == NULL) {
        return NGX_CONF_ERROR;
    }

    value = cf->args->elts;

    header->key = value[1];
    header->value = value[2];

    return NGX_CONF_OK;
}