From 967cfa7e5c1bfb4d2cf78bb3de3dc6d36b78c440 Mon Sep 17 00:00:00 2001 From: Jeremy Kerr Date: Thu, 14 Nov 2019 15:06:26 +0800 Subject: discover/grub2: implement 'source' command This change add support for the grub2 'source' command, executing a referenced script in the current parse context. We impose a limit of 10 (concurrent) source commands, to prevent infinite recursion. Signed-off-by: Jeremy Kerr --- discover/grub2/builtins.c | 51 ++++++++++++++++++- discover/grub2/grub2.h | 1 + test/parser/Makefile.am | 4 ++ test/parser/test-grub2-source-functions.c | 46 +++++++++++++++++ test/parser/test-grub2-source-recursion-infinite.c | 43 ++++++++++++++++ test/parser/test-grub2-source-recursion.c | 58 ++++++++++++++++++++++ test/parser/test-grub2-source.c | 54 ++++++++++++++++++++ 7 files changed, 256 insertions(+), 1 deletion(-) create mode 100644 test/parser/test-grub2-source-functions.c create mode 100644 test/parser/test-grub2-source-recursion-infinite.c create mode 100644 test/parser/test-grub2-source-recursion.c create mode 100644 test/parser/test-grub2-source.c diff --git a/discover/grub2/builtins.c b/discover/grub2/builtins.c index c726216..ab1407a 100644 --- a/discover/grub2/builtins.c +++ b/discover/grub2/builtins.c @@ -401,6 +401,51 @@ static int builtin_test(struct grub2_script *script, return rc ? 0 : 1; } +static int builtin_source(struct grub2_script *script, + void *data __attribute__((unused)), + int argc, char *argv[]) +{ + struct grub2_statements *statements; + struct discover_device *dev; + const char *filename; + char *path, *buf; + int rc, len; + + if (argc != 2) + return false; + + /* limit script recursion */ + if (script->include_depth >= 10) + return false; + + rc = parse_to_device_path(script, argv[1], &dev, &path); + if (rc) + return false; + + rc = parser_request_file(script->ctx, dev, path, &buf, &len); + if (rc) + return false; + + /* save current script state */ + statements = script->statements; + filename = script->filename; + script->include_depth++; + + rc = grub2_parser_parse(script->parser, argv[1], buf, len); + + if (!rc) + statements_execute(script, script->statements); + + talloc_free(script->statements); + + /* restore state */ + script->statements = statements; + script->filename = filename; + script->include_depth--; + + return !rc; +} + static int builtin_true(struct grub2_script *script __attribute__((unused)), void *data __attribute__((unused)), int argc __attribute__((unused)), @@ -491,7 +536,11 @@ static struct { { .name = "blscfg", .fn = builtin_blscfg, - } + }, + { + .name = "source", + .fn = builtin_source, + }, }; static const char *nops[] = { diff --git a/discover/grub2/grub2.h b/discover/grub2/grub2.h index deaf976..75f6aa0 100644 --- a/discover/grub2/grub2.h +++ b/discover/grub2/grub2.h @@ -100,6 +100,7 @@ struct grub2_script { const char *filename; unsigned int n_options; struct list options; + int include_depth; }; struct grub2_parser { diff --git a/test/parser/Makefile.am b/test/parser/Makefile.am index c8e059b..5f1a93b 100644 --- a/test/parser/Makefile.am +++ b/test/parser/Makefile.am @@ -46,6 +46,10 @@ parser_TESTS = \ test/parser/test-grub2-lexer-error \ test/parser/test-grub2-parser-error \ test/parser/test-grub2-test-file-ops \ + test/parser/test-grub2-source \ + test/parser/test-grub2-source-functions \ + test/parser/test-grub2-source-recursion \ + test/parser/test-grub2-source-recursion-infinite \ test/parser/test-grub2-single-yocto \ test/parser/test-grub2-blscfg-default-filename \ test/parser/test-grub2-blscfg-default-index \ diff --git a/test/parser/test-grub2-source-functions.c b/test/parser/test-grub2-source-functions.c new file mode 100644 index 0000000..a9da934 --- /dev/null +++ b/test/parser/test-grub2-source-functions.c @@ -0,0 +1,46 @@ + +/* check that we can source other scripts, and functions can be defined + * and called across sourced scripts */ + +#include "parser-test.h" + +#if 0 /* PARSER_EMBEDDED_CONFIG */ + +function f1 { + menuentry "f1$1" { linux $2 } +} + +source /grub/2.cfg + +f2 a /vmlinux + +#endif + +void run_test(struct parser_test *test) +{ + struct discover_boot_option *opt; + struct discover_context *ctx; + struct discover_device *dev; + + ctx = test->ctx; + dev = ctx->device; + + test_read_conf_embedded(test, "/grub/grub.cfg"); + + test_add_file_string(test, dev, + "/grub/2.cfg", + "function f2 { menuentry \"f2$1\" { linux $2 } }\n" + "f1 a /vmlinux\n"); + + test_run_parser(test, "grub2"); + + check_boot_option_count(ctx, 2); + + opt = get_boot_option(ctx, 0); + check_name(opt, "f1a"); + check_resolved_local_resource(opt->boot_image, dev, "/vmlinux"); + + opt = get_boot_option(ctx, 1); + check_name(opt, "f2a"); + check_resolved_local_resource(opt->boot_image, dev, "/vmlinux"); +} diff --git a/test/parser/test-grub2-source-recursion-infinite.c b/test/parser/test-grub2-source-recursion-infinite.c new file mode 100644 index 0000000..fbcc5a3 --- /dev/null +++ b/test/parser/test-grub2-source-recursion-infinite.c @@ -0,0 +1,43 @@ + +/* check that have a maximum source recursion limit */ + +#include "parser-test.h" + +#if 0 /* PARSER_EMBEDDED_CONFIG */ + +name=a$name + +menuentry $name { + linux /a +} + +source /grub/grub.cfg + +#endif + +void run_test(struct parser_test *test) +{ + struct discover_boot_option *opt; + struct discover_context *ctx; + struct discover_device *dev; + + ctx = test->ctx; + dev = ctx->device; + + test_read_conf_embedded(test, "/grub/grub.cfg"); + + test_run_parser(test, "grub2"); + + /* we error out after 10 levels, but we should still have + * parse results up to that point + */ + check_boot_option_count(ctx, 11); + + opt = get_boot_option(ctx, 0); + check_name(opt, "a"); + check_resolved_local_resource(opt->boot_image, dev, "/a"); + + opt = get_boot_option(ctx,10); + check_name(opt, "aaaaaaaaaaa"); + check_resolved_local_resource(opt->boot_image, dev, "/a"); +} diff --git a/test/parser/test-grub2-source-recursion.c b/test/parser/test-grub2-source-recursion.c new file mode 100644 index 0000000..21b6bd2 --- /dev/null +++ b/test/parser/test-grub2-source-recursion.c @@ -0,0 +1,58 @@ +/* check that we can source other files recursively */ + +#include "parser-test.h" + +#if 0 /* PARSER_EMBEDDED_CONFIG */ + +menuentry a { + linux /a +} + +source /grub/2.cfg + +menuentry c { + linux /c +} + +#endif + +void run_test(struct parser_test *test) +{ + struct discover_boot_option *opt; + struct discover_context *ctx; + struct discover_device *dev; + + ctx = test->ctx; + dev = ctx->device; + + test_read_conf_embedded(test, "/grub/grub.cfg"); + + /* four levels of config files, the last defining a boot option */ + test_add_file_string(test, dev, + "/grub/2.cfg", + "source /grub/3.cfg\n"); + + test_add_file_string(test, dev, + "/grub/3.cfg", + "source /grub/4.cfg\n"); + + test_add_file_string(test, dev, + "/grub/4.cfg", + "menuentry b { linux /b }\n"); + + test_run_parser(test, "grub2"); + + check_boot_option_count(ctx, 3); + + opt = get_boot_option(ctx, 0); + check_name(opt, "a"); + check_resolved_local_resource(opt->boot_image, dev, "/a"); + + opt = get_boot_option(ctx, 1); + check_name(opt, "b"); + check_resolved_local_resource(opt->boot_image, dev, "/b"); + + opt = get_boot_option(ctx, 2); + check_name(opt, "c"); + check_resolved_local_resource(opt->boot_image, dev, "/c"); +} diff --git a/test/parser/test-grub2-source.c b/test/parser/test-grub2-source.c new file mode 100644 index 0000000..a14bef7 --- /dev/null +++ b/test/parser/test-grub2-source.c @@ -0,0 +1,54 @@ + +/* check that we can source other scripts, and variables get passed + * in to and out of sourced scripts */ + +#include "parser-test.h" + +#if 0 /* PARSER_EMBEDDED_CONFIG */ + +menuentry a { + linux /a +} + +# var: outer -> inner -> outer +v=b + +source /grub/2.cfg + +menuentry $v { + linux /c +} + +#endif + +void run_test(struct parser_test *test) +{ + struct discover_boot_option *opt; + struct discover_context *ctx; + struct discover_device *dev; + + ctx = test->ctx; + dev = ctx->device; + + test_read_conf_embedded(test, "/grub/grub.cfg"); + + test_add_file_string(test, dev, + "/grub/2.cfg", + "menuentry $v { linux /b }\nv=c\n"); + + test_run_parser(test, "grub2"); + + check_boot_option_count(ctx, 3); + + opt = get_boot_option(ctx, 0); + check_name(opt, "a"); + check_resolved_local_resource(opt->boot_image, dev, "/a"); + + opt = get_boot_option(ctx, 1); + check_name(opt, "b"); + check_resolved_local_resource(opt->boot_image, dev, "/b"); + + opt = get_boot_option(ctx, 2); + check_name(opt, "c"); + check_resolved_local_resource(opt->boot_image, dev, "/c"); +} -- cgit v1.2.1