X-Git-Url: http://git.ozlabs.org/?p=petitboot;a=blobdiff_plain;f=discover%2Fpxe-parser.c;h=8237c4b46b2b29b8417fa661b8afacb70777b130;hp=67cb7882f46b77c85da01a8db7faa076773df7d3;hb=bdd5c29b008a4484ed141f934d97465d673a10b7;hpb=9d9f5fafe1ab15683601c03b14c35fe6a405ba45

diff --git a/discover/pxe-parser.c b/discover/pxe-parser.c
index 67cb788..8237c4b 100644
--- a/discover/pxe-parser.c
+++ b/discover/pxe-parser.c
@@ -1,39 +1,165 @@
 
+#if defined(HAVE_CONFIG_H)
+#include "config.h"
+#endif
+#include <stdlib.h>
 #include <string.h>
 
 #include <talloc/talloc.h>
 #include <url/url.h>
+#include <log/log.h>
+#include <file/file.h>
+#include <i18n/i18n.h>
 
 #include "parser.h"
 #include "parser-conf.h"
 #include "parser-utils.h"
 #include "resource.h"
+#include "paths.h"
+#include "event.h"
+#include "user-event.h"
+#include "network.h"
+
+static const char *pxelinux_prefix = "pxelinux.cfg/";
+
+static void pxe_conf_parse_cb(struct load_url_result *result, void *data);
+
+struct pxe_parser_info {
+	struct discover_boot_option	*opt;
+	const char			*default_name;
+	char				**pxe_conf_files;
+	struct pb_url			*pxe_base_url;
+	int				current;
+};
 
 static void pxe_finish(struct conf_context *conf)
 {
-	printf("%s\n", __func__);
-	discover_context_add_boot_option(conf->dc, conf->parser_info);
+	struct pxe_parser_info *info = conf->parser_info;
+	if (info->opt)
+		discover_context_add_boot_option(conf->dc, info->opt);
+}
+
+/* We need a slightly modified version of pb_url_join, to allow for the
+ * pxelinux "::filename" syntax for absolute URLs
+ */
+static struct pb_url *pxe_url_join(void *ctx, const struct pb_url *url,
+		const char *s)
+{
+	struct pb_url *new_url;
+	int len;
+
+	len = strlen(s);
+
+	if (len > 2 && s[0] == ':' && s[1] == ':') {
+		char *tmp;
+
+		if (s[2] == '/') {
+			/* ::/path -> /path */
+			tmp = talloc_strdup(ctx, s+2);
+		} else {
+			/* ::path -> /path */
+			tmp = talloc_strdup(ctx, s+1);
+			tmp[0] = '/';
+		}
+
+		new_url = pb_url_join(ctx, url, tmp);
+
+		talloc_free(tmp);
+
+	} else {
+		const char *tmp;
+		/* strip leading slashes */
+		for (tmp = s; *tmp == '/'; tmp++)
+			;
+		new_url = pb_url_join(ctx, url, tmp);
+	}
+
+	return new_url;
+}
+
+static void pxe_append_string(struct discover_boot_option *opt,
+		const char *str)
+{
+	if (opt->option->boot_args)
+		opt->option->boot_args = talloc_asprintf_append(
+				opt->option->boot_args, " %s", str);
+	else
+		opt->option->boot_args = talloc_strdup(opt->option, str);
+}
+
+static char *pxe_sysappend_mac(void *ctx, uint8_t *mac)
+{
+	if (!mac)
+		return NULL;
+
+	return talloc_asprintf(ctx,
+		"BOOTIF=01-%02x-%02x-%02x-%02x-%02x-%02x",
+		mac[0], mac[1], mac[2], mac[3], mac[4], mac[5]);
+}
+
+static void pxe_process_sysappend(struct discover_context *ctx,
+		struct discover_boot_option *opt,
+		unsigned long val)
+{
+	struct event *event = ctx->event;
+	char *str = NULL;
+
+	if (!event)
+		return;
+
+	if (val & 0x2) {
+		uint8_t *mac = find_mac_by_name(ctx, ctx->network,
+					event->device);
+		str = pxe_sysappend_mac(ctx, mac);
+		if (str) {
+			pxe_append_string(opt, str);
+			talloc_free(str);
+		}
+		val &= ~0x2;
+	}
+
+	if (val)
+		pb_log("pxe: unsupported features requested in "
+				"ipappend/sysappend: 0x%04lx", val);
+
 }
 
 static void pxe_process_pair(struct conf_context *ctx,
 		const char *name, char *value)
 {
-	struct discover_boot_option *opt = ctx->parser_info;
+	struct pxe_parser_info *parser_info = ctx->parser_info;
+	struct discover_boot_option *opt = parser_info->opt;
 	struct pb_url *url;
 
+	/* quirk in the syslinux config format: initrd can be separated
+	 * by an '=' */
+	if (!name && !strncasecmp(value, "initrd=", strlen("initrd="))) {
+		name = "initrd";
+		value += strlen("initrd=");
+	}
+
 	if (!name)
 		return;
 
+	if (streq(name, "DEFAULT")) {
+		parser_info->default_name = talloc_strdup(parser_info, value);
+		return;
+	}
+
 	if (streq(name, "LABEL")) {
 		if (opt)
 			pxe_finish(ctx);
 
 		opt = discover_boot_option_create(ctx->dc, ctx->dc->device);
-		ctx->parser_info = opt;
 
 		opt->option->name = talloc_strdup(opt, value);
 		opt->option->id = talloc_asprintf(opt, "%s@%p",
 				ctx->dc->device->device->id, opt);
+
+		opt->option->is_default = parser_info->default_name &&
+					streq(parser_info->default_name, value);
+
+		parser_info->opt = opt;
 		return;
 	}
 
@@ -42,39 +168,235 @@ static void pxe_process_pair(struct conf_context *ctx,
 		return;
 
 	if (streq(name, "KERNEL")) {
-		url = pb_url_join(ctx->dc, ctx->dc->conf_url, value);
+		url = pxe_url_join(ctx->dc, ctx->dc->conf_url, value);
 		opt->boot_image = create_url_resource(opt, url);
 
+		char* args_sigfile_default = talloc_asprintf(opt,
+			"%s.cmdline.sig", value);
+		url = pxe_url_join(ctx->dc, ctx->dc->conf_url,
+			args_sigfile_default);
+		opt->args_sig_file = create_url_resource(opt, url);
+		talloc_free(args_sigfile_default);
+
+	} else if (streq(name, "INITRD")) {
+		url = pxe_url_join(ctx->dc, ctx->dc->conf_url, value);
+		opt->initrd = create_url_resource(opt, url);
+
 	} else if (streq(name, "APPEND")) {
-		opt->option->boot_args = talloc_strdup(opt->option, value);
-		/* todo: initrd extraction */
+		char *str, *end;
+
+		pxe_append_string(opt, value);
+
+		str = strcasestr(value, "INITRD=");
+		if (str) {
+			str += strlen("INITRD=");
+			end = strchrnul(str, ' ');
+			*end = '\0';
+
+			url = pxe_url_join(ctx->dc, ctx->dc->conf_url, str);
+			opt->initrd = create_url_resource(opt, url);
+		}
+	} else if (streq(name, "SYSAPPEND") || streq(name, "IPAPPEND")) {
+		unsigned long type;
+		char *end;
+
+		type = strtoul(value, &end, 10);
+		if (end != value && !(*end))
+			pxe_process_sysappend(ctx->dc, opt, type);
+
+	} else if (streq(name, "DTB") || streq(name, "FDT")) {
+		url = pxe_url_join(ctx->dc, ctx->dc->conf_url, value);
+		opt->dtb = create_url_resource(opt, url);
+	}
+
+}
+
+static void pxe_load_next_filename(struct conf_context *conf)
+{
+	struct pxe_parser_info *info = conf->parser_info;
+	struct pb_url *url;
+
+	if (!info->pxe_conf_files)
+		return;
+
+	for (; info->pxe_conf_files[info->current]; info->current++) {
+		url = pb_url_join(conf->dc, info->pxe_base_url,
+				  info->pxe_conf_files[info->current]);
+		if (!url)
+			continue;
+
+		if (load_url_async(conf, url, pxe_conf_parse_cb, conf))
+			break;
 	}
+
+	return;
+}
+
+/*
+ * Callback for asynchronous loads from pxe_parse()
+ * @param result Result of load_url_async()
+ * @param data   Pointer to associated conf_context
+ */
+static void pxe_conf_parse_cb(struct load_url_result *result, void *data)
+{
+	struct conf_context *conf = data;
+	struct device_handler *handler;
+	struct pxe_parser_info *info;
+	char *buf = NULL;
+	int len, rc = 0;
+
+	if (!data)
+		return;
+
+	if (result && result->status == LOAD_OK)
+		rc = read_file(conf, result->local, &buf, &len);
+	if (!result || result->status != LOAD_OK || rc) {
+		/* This load failed so try the next available filename */
+		info = conf->parser_info;
+		if (!info->pxe_conf_files)
+			return;
+
+		info->current++;
+		pxe_load_next_filename(conf);
+		if (info->pxe_conf_files[info->current] == NULL) {
+			/* Nothing left to try */
+			goto out_clean;
+		}
+		return;
+	}
+
+	/*
+	 * Parse the first successfully downloaded file. We only want to parse
+	 * the first because otherwise we could parse options from both a
+	 * machine-specific config and a 'fallback' default config
+	 */
+
+	conf_parse_buf(conf, buf, len);
+
+	/* We may be called well after the original caller of iterate_parsers(),
+	 * commit any new boot options ourselves */
+	handler = talloc_parent(conf);
+	device_handler_discover_context_commit(handler, conf->dc);
+
+	/*
+	 * TRANSLATORS: the format specifier in this string in an IP address,
+	 * eg. 192.168.1.1
+	 */
+	device_handler_status_dev_info(handler, conf->dc->device,
+			_("Parsed PXE config from %s"),
+			conf->dc->conf_url->host);
+
+	talloc_free(buf);
+out_clean:
+	if (result->cleanup_local)
+		unlink(result->local);
+	talloc_free(conf);
 }
 
-static int pxe_parse(struct discover_context *dc, char *buf, int len)
+/**
+ * Return a new conf_context and increment the talloc reference count on
+ * the discover_context struct.
+ * @param  ctx  Parent talloc context
+ * @param  orig Original discover_context
+ * @return      Pointer to new conf_context
+ */
+static struct conf_context *copy_context(void *ctx, struct discover_context *dc)
 {
+	struct pxe_parser_info *info;
 	struct conf_context *conf;
 
-	conf = talloc_zero(dc, struct conf_context);
+	conf = talloc_zero(ctx, struct conf_context);
 
 	if (!conf)
-		return 0;
+		return NULL;
 
-	conf->dc = dc;
 	conf->get_pair = conf_get_pair_space;
 	conf->process_pair = pxe_process_pair;
 	conf->finish = pxe_finish;
+	info = talloc_zero(conf, struct pxe_parser_info);
+	if (!info) {
+		talloc_free(conf);
+		return NULL;
+	}
+	conf->parser_info = info;
 
-	conf_parse_buf(conf, buf, len);
+	/*
+	 * The discover_context may be freed once pxe_parse() returns, but the
+	 * callback will still need it. Take a reference so that that it will
+	 * persist until the last callback completes.
+	 */
+	conf->dc = talloc_reference(conf, dc);
+
+	return conf;
+}
+
+static int pxe_parse(struct discover_context *dc)
+{
+	struct pb_url *pxe_base_url;
+	struct conf_context *conf = NULL;
+	struct load_url_result *result;
+	void *ctx = talloc_parent(dc);
+	struct pxe_parser_info *info;
+	char **pxe_conf_files;
+	bool complete_url;
+
+	/* Expects dhcp event parameters to support network boot */
+	if (!dc->event)
+		return -1;
+
+	dc->conf_url = user_event_parse_conf_url(dc, dc->event, &complete_url);
+	if (!dc->conf_url)
+		return -1;
+
+	/*
+	 * Retrieving PXE configs over the network can take some time depending
+	 * on factors such as slow network, malformed paths, bad DNS, and
+	 * overzealous firewalls. Instead of blocking the discover server while
+	 * we wait for these, spawn an asynchronous job that will attempt to
+	 * retrieve each possible URL until it successfully finds one, and
+	 * parse and process the resulting file in a callback.
+	 */
+	conf = copy_context(ctx, dc);
+	if (!conf)
+		return -1;
+
+	if (complete_url) {
+		/* we have a complete URL; use this and we're done. */
+		result = load_url_async(conf->dc, conf->dc->conf_url,
+					pxe_conf_parse_cb, conf);
+		if (!result) {
+			pb_log("load_url_async fails for %s\n",
+					dc->conf_url->path);
+			goto out_conf;
+		}
+	} else {
+		pxe_conf_files = user_event_parse_conf_filenames(dc, dc->event);
+		if (!pxe_conf_files)
+			goto out_conf;
+
+		pxe_base_url = pb_url_join(dc, dc->conf_url, pxelinux_prefix);
+		if (!pxe_base_url)
+			goto out_pxe_conf;
+
+		info = conf->parser_info;
+		info->pxe_conf_files = pxe_conf_files;
+		info->pxe_base_url = pxe_base_url;
+
+		pxe_load_next_filename(conf);
+	}
+
+	return 0;
 
+out_pxe_conf:
+	talloc_free(pxe_conf_files);
+out_conf:
 	talloc_free(conf);
-	return 1;
+	return -1;
 }
 
 static struct parser pxe_parser = {
 	.name			= "pxe",
 	.parse			= pxe_parse,
-	.method			= CONF_METHOD_DHCP,
 };
 
 register_parser(pxe_parser);