From: Simon Glass <sjg@chromium.org> The pxe_utils.c file is quite large and has a mix of parsing and booting code. Split out the parsing into a new 'pxe_parse.c' file. Add function prototypes for parse_pxefile_top() and label_destroy(), the two functions used by pxe_utils.c Signed-off-by: Simon Glass <sjg@chromium.org> --- boot/Makefile | 2 +- boot/pxe_parse.c | 692 +++++++++++++++++++++++++++++++++++++++++++ boot/pxe_utils.c | 704 -------------------------------------------- include/pxe_utils.h | 24 ++ 4 files changed, 717 insertions(+), 705 deletions(-) create mode 100644 boot/pxe_parse.c diff --git a/boot/Makefile b/boot/Makefile index f4968cdcf7e..7f4126ec4ea 100644 --- a/boot/Makefile +++ b/boot/Makefile @@ -8,7 +8,7 @@ ifndef CONFIG_XPL_BUILD obj-$(CONFIG_BOOT_RETRY) += bootretry.o obj-$(CONFIG_BOOT) += bootm.o bootm_os.o -obj-$(CONFIG_PXE_UTILS) += pxe_utils.o +obj-$(CONFIG_PXE_UTILS) += pxe_utils.o pxe_parse.o endif diff --git a/boot/pxe_parse.c b/boot/pxe_parse.c new file mode 100644 index 00000000000..2402889ecdf --- /dev/null +++ b/boot/pxe_parse.c @@ -0,0 +1,692 @@ +// SPDX-License-Identifier: GPL-2.0+ +/* + * Copyright 2010-2011 Calxeda, Inc. + * Copyright (c) 2014, NVIDIA CORPORATION. All rights reserved. + */ + +#define LOG_CATEGORY LOGC_BOOT + +#include <ctype.h> +#include <malloc.h> +#include <mapmem.h> +#include "pxe_utils.h" + +/** enum token_type - Tokens for the pxe file parser */ +enum token_type { + T_EOL, + T_STRING, + T_EOF, + T_MENU, + T_TITLE, + T_TIMEOUT, + T_LABEL, + T_KERNEL, + T_LINUX, + T_APPEND, + T_INITRD, + T_LOCALBOOT, + T_DEFAULT, + T_PROMPT, + T_INCLUDE, + T_FDT, + T_FDTDIR, + T_FDTOVERLAYS, + T_ONTIMEOUT, + T_IPAPPEND, + T_BACKGROUND, + T_KASLRSEED, + T_FALLBACK, + T_SAY, + T_INVALID +}; + +/** struct token - token - given by a value and a type */ +struct token { + char *val; + enum token_type type; +}; + +/* Keywords recognized */ +static const struct token keywords[] = { + {"menu", T_MENU}, + {"title", T_TITLE}, + {"timeout", T_TIMEOUT}, + {"default", T_DEFAULT}, + {"prompt", T_PROMPT}, + {"label", T_LABEL}, + {"kernel", T_KERNEL}, + {"linux", T_LINUX}, + {"localboot", T_LOCALBOOT}, + {"append", T_APPEND}, + {"initrd", T_INITRD}, + {"include", T_INCLUDE}, + {"devicetree", T_FDT}, + {"fdt", T_FDT}, + {"devicetreedir", T_FDTDIR}, + {"fdtdir", T_FDTDIR}, + {"fdtoverlays", T_FDTOVERLAYS}, + {"devicetree-overlay", T_FDTOVERLAYS}, + {"ontimeout", T_ONTIMEOUT,}, + {"ipappend", T_IPAPPEND,}, + {"background", T_BACKGROUND,}, + {"kaslrseed", T_KASLRSEED,}, + {"fallback", T_FALLBACK,}, + {"say", T_SAY,}, + {NULL, T_INVALID} +}; + +/** + * enum lex_state - lexer state + * + * Since pxe(linux) files don't have a token to identify the start of a + * literal, we have to keep track of when we're in a state where a literal is + * expected vs when we're in a state a keyword is expected. + */ +enum lex_state { + L_NORMAL = 0, + L_KEYWORD, + L_SLITERAL +}; + +/** + * label_create() - crate a new PXE label + * + * Allocates memory for and initializes a pxe_label. This uses malloc, so the + * result must be free()'d to reclaim the memory. + * + * Returns a pointer to the label, or NULL if out of memory + */ +static struct pxe_label *label_create(void) +{ + struct pxe_label *label; + + label = malloc(sizeof(struct pxe_label)); + if (!label) + return NULL; + + memset(label, 0, sizeof(struct pxe_label)); + + return label; +} + +void label_destroy(struct pxe_label *label) +{ + free(label->name); + free(label->kernel_label); + free(label->kernel); + free(label->config); + free(label->append); + free(label->initrd); + free(label->fdt); + free(label->fdtdir); + free(label->fdtoverlays); + free(label); +} + +/** + * get_string() - retrieves a string from *p and stores it as a token in *t. + * + * This is used for scanning both string literals and keywords. + * + * Characters from *p are copied into t-val until a character equal to + * delim is found, or a NUL byte is reached. If delim has the special value of + * ' ', any whitespace character will be used as a delimiter. + * + * If lower is unequal to 0, uppercase characters will be converted to + * lowercase in the result. This is useful to make keywords case + * insensitive. + * + * The location of *p is updated to point to the first character after the end + * of the token - the ending delimiter. + * + * Memory for t->val is allocated using malloc and must be free()'d to reclaim + * it. + * + * @p: Points to a pointer to the current position in the input being processed. + * Updated to point at the first character after the current token + * @t: Pointers to a token to fill in + * @delim: Delimiter character to look for, either newline or space + * @lower: true to convert the string to lower case when storing + * Returns the new value of t->val, on success, NULL if out of memory + */ +static char *get_string(char **p, struct token *t, char delim, int lower) +{ + char *b, *e; + size_t len, i; + + /* + * b and e both start at the beginning of the input stream. + * + * e is incremented until we find the ending delimiter, or a NUL byte + * is reached. Then, we take e - b to find the length of the token. + */ + b = *p; + e = *p; + while (*e) { + if ((delim == ' ' && isspace(*e)) || delim == *e) + break; + e++; + } + + len = e - b; + + /* + * Allocate memory to hold the string, and copy it in, converting + * characters to lowercase if lower is != 0. + */ + t->val = malloc(len + 1); + if (!t->val) + return NULL; + + for (i = 0; i < len; i++, b++) { + if (lower) + t->val[i] = tolower(*b); + else + t->val[i] = *b; + } + + t->val[len] = '\0'; + + /* Update *p so the caller knows where to continue scanning */ + *p = e; + t->type = T_STRING; + + return t->val; +} + +/** + * get_keyword() - Populate a keyword token with a type and value + * + * Updates the ->type field based on the keyword string in @val + * @t: Token to populate + */ +static void get_keyword(struct token *t) +{ + int i; + + for (i = 0; keywords[i].val; i++) { + if (!strcmp(t->val, keywords[i].val)) { + t->type = keywords[i].type; + break; + } + } +} + +/** + * get_token() - Get the next token + * + * We have to keep track of which state we're in to know if we're looking to get + * a string literal or a keyword. + * + * @p: Points to a pointer to the current position in the input being processed. + * Updated to point at the first character after the current token + */ +static void get_token(char **p, struct token *t, enum lex_state state) +{ + char *c = *p; + + t->type = T_INVALID; + + /* eat non EOL whitespace */ + while (isblank(*c)) + c++; + + /* + * eat comments. note that string literals can't begin with #, but + * can contain a # after their first character. + */ + if (*c == '#') { + while (*c && *c != '\n') + c++; + } + + if (*c == '\n') { + t->type = T_EOL; + c++; + } else if (*c == '\0') { + t->type = T_EOF; + c++; + } else if (state == L_SLITERAL) { + get_string(&c, t, '\n', 0); + } else if (state == L_KEYWORD) { + /* + * when we expect a keyword, we first get the next string + * token delimited by whitespace, and then check if it + * matches a keyword in our keyword list. if it does, it's + * converted to a keyword token of the appropriate type, and + * if not, it remains a string token. + */ + get_string(&c, t, ' ', 1); + get_keyword(t); + } + + *p = c; +} + +/** + * eol_or_eof() - Find end of line + * + * Increment *c until we get to the end of the current line, or EOF + * + * @c: Points to a pointer to the current position in the input being processed. + * Updated to point at the first character after the current token + */ +static void eol_or_eof(char **c) +{ + while (**c && **c != '\n') + (*c)++; +} + +/* + * All of these parse_* functions share some common behavior. + * + * They finish with *c pointing after the token they parse, and return 1 on + * success, or < 0 on error. + */ + +/* + * Parse a string literal and store a pointer it at *dst. String literals + * terminate at the end of the line. + */ +static int parse_sliteral(char **c, char **dst) +{ + struct token t; + char *s = *c; + + get_token(c, &t, L_SLITERAL); + + if (t.type != T_STRING) { + printf("Expected string literal: %.*s\n", (int)(*c - s), s); + return -EINVAL; + } + + *dst = t.val; + + return 1; +} + +/* + * Parse a base 10 (unsigned) integer and store it at *dst. + */ +static int parse_integer(char **c, int *dst) +{ + struct token t; + char *s = *c; + + get_token(c, &t, L_SLITERAL); + if (t.type != T_STRING) { + printf("Expected string: %.*s\n", (int)(*c - s), s); + return -EINVAL; + } + + *dst = simple_strtol(t.val, NULL, 10); + + free(t.val); + + return 1; +} + +/* + * Parse an include statement, and retrieve and parse the file it mentions. + * + * base should point to a location where it's safe to store the file, and + * nest_level should indicate how many nested includes have occurred. For this + * include, nest_level has already been incremented and doesn't need to be + * incremented here. + */ +static int handle_include(struct pxe_context *ctx, char **c, unsigned long base, + struct pxe_menu *cfg, int nest_level) +{ + char *include_path; + char *s = *c; + int err; + char *buf; + int ret; + + err = parse_sliteral(c, &include_path); + if (err < 0) { + printf("Expected include path: %.*s\n", (int)(*c - s), s); + return err; + } + + err = get_pxe_file(ctx, include_path, base); + if (err < 0) { + printf("Couldn't retrieve %s\n", include_path); + return err; + } + + buf = map_sysmem(base, 0); + ret = parse_pxefile_top(ctx, buf, base, cfg, nest_level); + unmap_sysmem(buf); + + return ret; +} + +/* + * Parse lines that begin with 'menu'. + * + * base and nest are provided to handle the 'menu include' case. + * + * base should point to a location where it's safe to store the included file. + * + * nest_level should be 1 when parsing the top level pxe file, 2 when parsing + * a file it includes, 3 when parsing a file included by that file, and so on. + */ +static int parse_menu(struct pxe_context *ctx, char **c, struct pxe_menu *cfg, + unsigned long base, int nest_level) +{ + struct token t; + char *s = *c; + int err = 0; + + get_token(c, &t, L_KEYWORD); + + switch (t.type) { + case T_TITLE: + err = parse_sliteral(c, &cfg->title); + + break; + + case T_INCLUDE: + err = handle_include(ctx, c, base, cfg, nest_level + 1); + break; + + case T_BACKGROUND: + err = parse_sliteral(c, &cfg->bmp); + break; + + default: + printf("Ignoring malformed menu command: %.*s\n", + (int)(*c - s), s); + } + if (err < 0) + return err; + + eol_or_eof(c); + + return 1; +} + +/* + * Handles parsing a 'menu line' when we're parsing a label. + */ +static int parse_label_menu(char **c, struct pxe_menu *cfg, + struct pxe_label *label) +{ + struct token t; + char *s; + + s = *c; + + get_token(c, &t, L_KEYWORD); + + switch (t.type) { + case T_DEFAULT: + if (!cfg->default_label) + cfg->default_label = strdup(label->name); + + if (!cfg->default_label) + return -ENOMEM; + + break; + case T_LABEL: + parse_sliteral(c, &label->menu); + break; + default: + printf("Ignoring malformed menu command: %.*s\n", + (int)(*c - s), s); + } + + eol_or_eof(c); + + return 0; +} + +/* + * Handles parsing a 'kernel' label. + * expecting "filename" or "<fit_filename>#cfg" + */ +static int parse_label_kernel(char **c, struct pxe_label *label) +{ + char *s; + int err; + + err = parse_sliteral(c, &label->kernel); + if (err < 0) + return err; + + /* copy the kernel label to compare with FDT / INITRD when FIT is used */ + label->kernel_label = strdup(label->kernel); + if (!label->kernel_label) + return -ENOMEM; + + s = strstr(label->kernel, "#"); + if (!s) + return 1; + + label->config = strdup(s); + if (!label->config) + return -ENOMEM; + + *s = 0; + + return 1; +} + +/* + * Parses a label and adds it to the list of labels for a menu. + * + * A label ends when we either get to the end of a file, or + * get some input we otherwise don't have a handler defined + * for. + * + */ +static int parse_label(char **c, struct pxe_menu *cfg) +{ + struct token t; + int len; + char *s = *c; + struct pxe_label *label; + int err; + + label = label_create(); + if (!label) + return -ENOMEM; + + err = parse_sliteral(c, &label->name); + if (err < 0) { + printf("Expected label name: %.*s\n", (int)(*c - s), s); + label_destroy(label); + return -EINVAL; + } + + list_add_tail(&label->list, &cfg->labels); + + while (1) { + s = *c; + get_token(c, &t, L_KEYWORD); + + err = 0; + switch (t.type) { + case T_MENU: + err = parse_label_menu(c, cfg, label); + break; + + case T_KERNEL: + case T_LINUX: + err = parse_label_kernel(c, label); + break; + + case T_APPEND: + err = parse_sliteral(c, &label->append); + if (label->initrd) + break; + s = strstr(label->append, "initrd="); + if (!s) + break; + s += 7; + len = (int)(strchr(s, ' ') - s); + label->initrd = malloc(len + 1); + strlcpy(label->initrd, s, len); + label->initrd[len] = '\0'; + + break; + + case T_INITRD: + if (!label->initrd) + err = parse_sliteral(c, &label->initrd); + break; + + case T_FDT: + if (!label->fdt) + err = parse_sliteral(c, &label->fdt); + break; + + case T_FDTDIR: + if (!label->fdtdir) + err = parse_sliteral(c, &label->fdtdir); + break; + + case T_FDTOVERLAYS: + if (!label->fdtoverlays) + err = parse_sliteral(c, &label->fdtoverlays); + break; + + case T_LOCALBOOT: + label->localboot = 1; + err = parse_integer(c, &label->localboot_val); + break; + + case T_IPAPPEND: + err = parse_integer(c, &label->ipappend); + break; + + case T_KASLRSEED: + label->kaslrseed = 1; + break; + + case T_EOL: + break; + case T_SAY: { + char *p = strchr(s, '\n'); + + if (p) { + printf("%.*s\n", (int)(p - *c) - 1, *c + 1); + + *c = p; + } + break; + } + default: + /* + * put the token back! we don't want it - it's the end + * of a label and whatever token this is, it's + * something for the menu level context to handle. + */ + *c = s; + return 1; + } + + if (err < 0) + return err; + } +} + +/* + * This 16 comes from the limit pxelinux imposes on nested includes. + * + * There is no reason at all we couldn't do more, but some limit helps prevent + * infinite (until crash occurs) recursion if a file tries to include itself. + */ +#define MAX_NEST_LEVEL 16 + +int parse_pxefile_top(struct pxe_context *ctx, char *p, ulong base, + struct pxe_menu *cfg, int nest_level) +{ + struct token t; + char *s, *b, *label_name; + int err; + + b = p; + + if (nest_level > MAX_NEST_LEVEL) { + printf("Maximum nesting (%d) exceeded\n", MAX_NEST_LEVEL); + return -EMLINK; + } + + while (1) { + s = p; + + get_token(&p, &t, L_KEYWORD); + + err = 0; + switch (t.type) { + case T_MENU: + cfg->prompt = 1; + err = parse_menu(ctx, &p, cfg, + base + ALIGN(strlen(b) + 1, 4), + nest_level); + break; + + case T_TIMEOUT: + err = parse_integer(&p, &cfg->timeout); + break; + + case T_LABEL: + err = parse_label(&p, cfg); + break; + + case T_DEFAULT: + case T_ONTIMEOUT: + err = parse_sliteral(&p, &label_name); + + if (label_name) { + if (cfg->default_label) + free(cfg->default_label); + + cfg->default_label = label_name; + } + + break; + + case T_FALLBACK: + err = parse_sliteral(&p, &label_name); + + if (label_name) { + if (cfg->fallback_label) + free(cfg->fallback_label); + + cfg->fallback_label = label_name; + } + + break; + + case T_INCLUDE: + err = handle_include(ctx, &p, + base + ALIGN(strlen(b), 4), cfg, + nest_level + 1); + break; + + case T_PROMPT: + err = parse_integer(&p, &cfg->prompt); + // Do not fail if prompt configuration is undefined + if (err < 0) + eol_or_eof(&p); + break; + + case T_EOL: + break; + + case T_EOF: + return 1; + + default: + printf("Ignoring unknown command: %.*s\n", + (int)(p - s), s); + eol_or_eof(&p); + } + + if (err < 0) + return err; + } +} diff --git a/boot/pxe_utils.c b/boot/pxe_utils.c index 23c23038a92..8ff06ce6c52 100644 --- a/boot/pxe_utils.c +++ b/boot/pxe_utils.c @@ -216,54 +216,6 @@ static int get_relfile_envaddr(struct pxe_context *ctx, const char *file_path, return get_relfile(ctx, file_path, file_addr, type, filesizep); } -/** - * label_create() - crate a new PXE label - * - * Allocates memory for and initializes a pxe_label. This uses malloc, so the - * result must be free()'d to reclaim the memory. - * - * Returns a pointer to the label, or NULL if out of memory - */ -static struct pxe_label *label_create(void) -{ - struct pxe_label *label; - - label = malloc(sizeof(struct pxe_label)); - if (!label) - return NULL; - - memset(label, 0, sizeof(struct pxe_label)); - - return label; -} - -/** - * label_destroy() - free the memory used by a pxe_label - * - * This frees @label itself as well as memory used by its name, - * kernel, config, append, initrd, fdt, fdtdir and fdtoverlay members, if - * they're non-NULL. - * - * So - be sure to only use dynamically allocated memory for the members of - * the pxe_label struct, unless you want to clean it up first. These are - * currently only created by the pxe file parsing code. - * - * @label: Label to free - */ -static void label_destroy(struct pxe_label *label) -{ - free(label->name); - free(label->kernel_label); - free(label->kernel); - free(label->config); - free(label->append); - free(label->initrd); - free(label->fdt); - free(label->fdtdir); - free(label->fdtoverlays); - free(label); -} - /** * label_print() - Print a label and its string members if they're defined * @@ -866,662 +818,6 @@ cleanup: return 1; /* returning is always failure */ } -/** enum token_type - Tokens for the pxe file parser */ -enum token_type { - T_EOL, - T_STRING, - T_EOF, - T_MENU, - T_TITLE, - T_TIMEOUT, - T_LABEL, - T_KERNEL, - T_LINUX, - T_APPEND, - T_INITRD, - T_LOCALBOOT, - T_DEFAULT, - T_PROMPT, - T_INCLUDE, - T_FDT, - T_FDTDIR, - T_FDTOVERLAYS, - T_ONTIMEOUT, - T_IPAPPEND, - T_BACKGROUND, - T_KASLRSEED, - T_FALLBACK, - T_SAY, - T_INVALID -}; - -/** struct token - token - given by a value and a type */ -struct token { - char *val; - enum token_type type; -}; - -/* Keywords recognized */ -static const struct token keywords[] = { - {"menu", T_MENU}, - {"title", T_TITLE}, - {"timeout", T_TIMEOUT}, - {"default", T_DEFAULT}, - {"prompt", T_PROMPT}, - {"label", T_LABEL}, - {"kernel", T_KERNEL}, - {"linux", T_LINUX}, - {"localboot", T_LOCALBOOT}, - {"append", T_APPEND}, - {"initrd", T_INITRD}, - {"include", T_INCLUDE}, - {"devicetree", T_FDT}, - {"fdt", T_FDT}, - {"devicetreedir", T_FDTDIR}, - {"fdtdir", T_FDTDIR}, - {"fdtoverlays", T_FDTOVERLAYS}, - {"devicetree-overlay", T_FDTOVERLAYS}, - {"ontimeout", T_ONTIMEOUT,}, - {"ipappend", T_IPAPPEND,}, - {"background", T_BACKGROUND,}, - {"kaslrseed", T_KASLRSEED,}, - {"fallback", T_FALLBACK,}, - {"say", T_SAY,}, - {NULL, T_INVALID} -}; - -/** - * enum lex_state - lexer state - * - * Since pxe(linux) files don't have a token to identify the start of a - * literal, we have to keep track of when we're in a state where a literal is - * expected vs when we're in a state a keyword is expected. - */ -enum lex_state { - L_NORMAL = 0, - L_KEYWORD, - L_SLITERAL -}; - -/** - * get_string() - retrieves a string from *p and stores it as a token in *t. - * - * This is used for scanning both string literals and keywords. - * - * Characters from *p are copied into t-val until a character equal to - * delim is found, or a NUL byte is reached. If delim has the special value of - * ' ', any whitespace character will be used as a delimiter. - * - * If lower is unequal to 0, uppercase characters will be converted to - * lowercase in the result. This is useful to make keywords case - * insensitive. - * - * The location of *p is updated to point to the first character after the end - * of the token - the ending delimiter. - * - * Memory for t->val is allocated using malloc and must be free()'d to reclaim - * it. - * - * @p: Points to a pointer to the current position in the input being processed. - * Updated to point at the first character after the current token - * @t: Pointers to a token to fill in - * @delim: Delimiter character to look for, either newline or space - * @lower: true to convert the string to lower case when storing - * Returns the new value of t->val, on success, NULL if out of memory - */ -static char *get_string(char **p, struct token *t, char delim, int lower) -{ - char *b, *e; - size_t len, i; - - /* - * b and e both start at the beginning of the input stream. - * - * e is incremented until we find the ending delimiter, or a NUL byte - * is reached. Then, we take e - b to find the length of the token. - */ - b = *p; - e = *p; - while (*e) { - if ((delim == ' ' && isspace(*e)) || delim == *e) - break; - e++; - } - - len = e - b; - - /* - * Allocate memory to hold the string, and copy it in, converting - * characters to lowercase if lower is != 0. - */ - t->val = malloc(len + 1); - if (!t->val) - return NULL; - - for (i = 0; i < len; i++, b++) { - if (lower) - t->val[i] = tolower(*b); - else - t->val[i] = *b; - } - - t->val[len] = '\0'; - - /* Update *p so the caller knows where to continue scanning */ - *p = e; - t->type = T_STRING; - - return t->val; -} - -/** - * get_keyword() - Populate a keyword token with a type and value - * - * Updates the ->type field based on the keyword string in @val - * @t: Token to populate - */ -static void get_keyword(struct token *t) -{ - int i; - - for (i = 0; keywords[i].val; i++) { - if (!strcmp(t->val, keywords[i].val)) { - t->type = keywords[i].type; - break; - } - } -} - -/** - * get_token() - Get the next token - * - * We have to keep track of which state we're in to know if we're looking to get - * a string literal or a keyword. - * - * @p: Points to a pointer to the current position in the input being processed. - * Updated to point at the first character after the current token - */ -static void get_token(char **p, struct token *t, enum lex_state state) -{ - char *c = *p; - - t->type = T_INVALID; - - /* eat non EOL whitespace */ - while (isblank(*c)) - c++; - - /* - * eat comments. note that string literals can't begin with #, but - * can contain a # after their first character. - */ - if (*c == '#') { - while (*c && *c != '\n') - c++; - } - - if (*c == '\n') { - t->type = T_EOL; - c++; - } else if (*c == '\0') { - t->type = T_EOF; - c++; - } else if (state == L_SLITERAL) { - get_string(&c, t, '\n', 0); - } else if (state == L_KEYWORD) { - /* - * when we expect a keyword, we first get the next string - * token delimited by whitespace, and then check if it - * matches a keyword in our keyword list. if it does, it's - * converted to a keyword token of the appropriate type, and - * if not, it remains a string token. - */ - get_string(&c, t, ' ', 1); - get_keyword(t); - } - - *p = c; -} - -/** - * eol_or_eof() - Find end of line - * - * Increment *c until we get to the end of the current line, or EOF - * - * @c: Points to a pointer to the current position in the input being processed. - * Updated to point at the first character after the current token - */ -static void eol_or_eof(char **c) -{ - while (**c && **c != '\n') - (*c)++; -} - -/* - * All of these parse_* functions share some common behavior. - * - * They finish with *c pointing after the token they parse, and return 1 on - * success, or < 0 on error. - */ - -/* - * Parse a string literal and store a pointer it at *dst. String literals - * terminate at the end of the line. - */ -static int parse_sliteral(char **c, char **dst) -{ - struct token t; - char *s = *c; - - get_token(c, &t, L_SLITERAL); - - if (t.type != T_STRING) { - printf("Expected string literal: %.*s\n", (int)(*c - s), s); - return -EINVAL; - } - - *dst = t.val; - - return 1; -} - -/* - * Parse a base 10 (unsigned) integer and store it at *dst. - */ -static int parse_integer(char **c, int *dst) -{ - struct token t; - char *s = *c; - - get_token(c, &t, L_SLITERAL); - if (t.type != T_STRING) { - printf("Expected string: %.*s\n", (int)(*c - s), s); - return -EINVAL; - } - - *dst = simple_strtol(t.val, NULL, 10); - - free(t.val); - - return 1; -} - -static int parse_pxefile_top(struct pxe_context *ctx, char *p, ulong base, - struct pxe_menu *cfg, int nest_level); - -/* - * Parse an include statement, and retrieve and parse the file it mentions. - * - * base should point to a location where it's safe to store the file, and - * nest_level should indicate how many nested includes have occurred. For this - * include, nest_level has already been incremented and doesn't need to be - * incremented here. - */ -static int handle_include(struct pxe_context *ctx, char **c, unsigned long base, - struct pxe_menu *cfg, int nest_level) -{ - char *include_path; - char *s = *c; - int err; - char *buf; - int ret; - - err = parse_sliteral(c, &include_path); - if (err < 0) { - printf("Expected include path: %.*s\n", (int)(*c - s), s); - return err; - } - - err = get_pxe_file(ctx, include_path, base); - if (err < 0) { - printf("Couldn't retrieve %s\n", include_path); - return err; - } - - buf = map_sysmem(base, 0); - ret = parse_pxefile_top(ctx, buf, base, cfg, nest_level); - unmap_sysmem(buf); - - return ret; -} - -/* - * Parse lines that begin with 'menu'. - * - * base and nest are provided to handle the 'menu include' case. - * - * base should point to a location where it's safe to store the included file. - * - * nest_level should be 1 when parsing the top level pxe file, 2 when parsing - * a file it includes, 3 when parsing a file included by that file, and so on. - */ -static int parse_menu(struct pxe_context *ctx, char **c, struct pxe_menu *cfg, - unsigned long base, int nest_level) -{ - struct token t; - char *s = *c; - int err = 0; - - get_token(c, &t, L_KEYWORD); - - switch (t.type) { - case T_TITLE: - err = parse_sliteral(c, &cfg->title); - - break; - - case T_INCLUDE: - err = handle_include(ctx, c, base, cfg, nest_level + 1); - break; - - case T_BACKGROUND: - err = parse_sliteral(c, &cfg->bmp); - break; - - default: - printf("Ignoring malformed menu command: %.*s\n", - (int)(*c - s), s); - } - if (err < 0) - return err; - - eol_or_eof(c); - - return 1; -} - -/* - * Handles parsing a 'menu line' when we're parsing a label. - */ -static int parse_label_menu(char **c, struct pxe_menu *cfg, - struct pxe_label *label) -{ - struct token t; - char *s; - - s = *c; - - get_token(c, &t, L_KEYWORD); - - switch (t.type) { - case T_DEFAULT: - if (!cfg->default_label) - cfg->default_label = strdup(label->name); - - if (!cfg->default_label) - return -ENOMEM; - - break; - case T_LABEL: - parse_sliteral(c, &label->menu); - break; - default: - printf("Ignoring malformed menu command: %.*s\n", - (int)(*c - s), s); - } - - eol_or_eof(c); - - return 0; -} - -/* - * Handles parsing a 'kernel' label. - * expecting "filename" or "<fit_filename>#cfg" - */ -static int parse_label_kernel(char **c, struct pxe_label *label) -{ - char *s; - int err; - - err = parse_sliteral(c, &label->kernel); - if (err < 0) - return err; - - /* copy the kernel label to compare with FDT / INITRD when FIT is used */ - label->kernel_label = strdup(label->kernel); - if (!label->kernel_label) - return -ENOMEM; - - s = strstr(label->kernel, "#"); - if (!s) - return 1; - - label->config = strdup(s); - if (!label->config) - return -ENOMEM; - - *s = 0; - - return 1; -} - -/* - * Parses a label and adds it to the list of labels for a menu. - * - * A label ends when we either get to the end of a file, or - * get some input we otherwise don't have a handler defined - * for. - * - */ -static int parse_label(char **c, struct pxe_menu *cfg) -{ - struct token t; - int len; - char *s = *c; - struct pxe_label *label; - int err; - - label = label_create(); - if (!label) - return -ENOMEM; - - err = parse_sliteral(c, &label->name); - if (err < 0) { - printf("Expected label name: %.*s\n", (int)(*c - s), s); - label_destroy(label); - return -EINVAL; - } - - list_add_tail(&label->list, &cfg->labels); - - while (1) { - s = *c; - get_token(c, &t, L_KEYWORD); - - err = 0; - switch (t.type) { - case T_MENU: - err = parse_label_menu(c, cfg, label); - break; - - case T_KERNEL: - case T_LINUX: - err = parse_label_kernel(c, label); - break; - - case T_APPEND: - err = parse_sliteral(c, &label->append); - if (label->initrd) - break; - s = strstr(label->append, "initrd="); - if (!s) - break; - s += 7; - len = (int)(strchr(s, ' ') - s); - label->initrd = malloc(len + 1); - strncpy(label->initrd, s, len); - label->initrd[len] = '\0'; - - break; - - case T_INITRD: - if (!label->initrd) - err = parse_sliteral(c, &label->initrd); - break; - - case T_FDT: - if (!label->fdt) - err = parse_sliteral(c, &label->fdt); - break; - - case T_FDTDIR: - if (!label->fdtdir) - err = parse_sliteral(c, &label->fdtdir); - break; - - case T_FDTOVERLAYS: - if (!label->fdtoverlays) - err = parse_sliteral(c, &label->fdtoverlays); - break; - - case T_LOCALBOOT: - label->localboot = 1; - err = parse_integer(c, &label->localboot_val); - break; - - case T_IPAPPEND: - err = parse_integer(c, &label->ipappend); - break; - - case T_KASLRSEED: - label->kaslrseed = 1; - break; - - case T_EOL: - break; - - case T_SAY: { - char *p = strchr(s, '\n'); - - if (p) { - printf("%.*s\n", (int)(p - *c) - 1, *c + 1); - - *c = p; - } - break; - } - - default: - /* - * put the token back! we don't want it - it's the end - * of a label and whatever token this is, it's - * something for the menu level context to handle. - */ - *c = s; - return 1; - } - - if (err < 0) - return err; - } -} - -/* - * This 16 comes from the limit pxelinux imposes on nested includes. - * - * There is no reason at all we couldn't do more, but some limit helps prevent - * infinite (until crash occurs) recursion if a file tries to include itself. - */ -#define MAX_NEST_LEVEL 16 - -/* - * Entry point for parsing a menu file. nest_level indicates how many times - * we've nested in includes. It will be 1 for the top level menu file. - * - * Returns 1 on success, < 0 on error. - */ -static int parse_pxefile_top(struct pxe_context *ctx, char *p, unsigned long base, - struct pxe_menu *cfg, int nest_level) -{ - struct token t; - char *s, *b, *label_name; - int err; - - b = p; - - if (nest_level > MAX_NEST_LEVEL) { - printf("Maximum nesting (%d) exceeded\n", MAX_NEST_LEVEL); - return -EMLINK; - } - - while (1) { - s = p; - - get_token(&p, &t, L_KEYWORD); - - err = 0; - switch (t.type) { - case T_MENU: - cfg->prompt = 1; - err = parse_menu(ctx, &p, cfg, - base + ALIGN(strlen(b) + 1, 4), - nest_level); - break; - - case T_TIMEOUT: - err = parse_integer(&p, &cfg->timeout); - break; - - case T_LABEL: - err = parse_label(&p, cfg); - break; - - case T_DEFAULT: - case T_ONTIMEOUT: - err = parse_sliteral(&p, &label_name); - - if (label_name) { - if (cfg->default_label) - free(cfg->default_label); - - cfg->default_label = label_name; - } - - break; - - case T_FALLBACK: - err = parse_sliteral(&p, &label_name); - - if (label_name) { - if (cfg->fallback_label) - free(cfg->fallback_label); - - cfg->fallback_label = label_name; - } - - break; - - case T_INCLUDE: - err = handle_include(ctx, &p, - base + ALIGN(strlen(b), 4), cfg, - nest_level + 1); - break; - - case T_PROMPT: - err = parse_integer(&p, &cfg->prompt); - // Do not fail if prompt configuration is undefined - if (err < 0) - eol_or_eof(&p); - break; - - case T_EOL: - break; - - case T_EOF: - return 1; - - default: - printf("Ignoring unknown command: %.*s\n", - (int)(p - s), s); - eol_or_eof(&p); - } - - if (err < 0) - return err; - } -} - /* */ void destroy_pxe_menu(struct pxe_menu *cfg) diff --git a/include/pxe_utils.h b/include/pxe_utils.h index 6425e349d19..a63d0123059 100644 --- a/include/pxe_utils.h +++ b/include/pxe_utils.h @@ -324,4 +324,28 @@ int pxe_probe(struct pxe_context *ctx, ulong pxefile_addr_r, bool prompt); */ int pxe_do_boot(struct pxe_context *ctx); +/* + * Entry point for parsing a menu file. nest_level indicates how many times + * we've nested in includes. It will be 1 for the top level menu file. + * + * Returns 1 on success, < 0 on error. + */ +int parse_pxefile_top(struct pxe_context *ctx, char *p, ulong base, + struct pxe_menu *cfg, int nest_level); + +/** + * label_destroy() - free the memory used by a pxe_label + * + * This frees @label itself as well as memory used by its name, + * kernel, config, append, initrd, fdt, fdtdir and fdtoverlay members, if + * they're non-NULL. + * + * So - be sure to only use dynamically allocated memory for the members of + * the pxe_label struct, unless you want to clean it up first. These are + * currently only created by the pxe file parsing code. + * + * @label: Label to free + */ +void label_destroy(struct pxe_label *label); + #endif /* __PXE_UTILS_H */ -- 2.43.0