Return-Path: Received: (majordomo@vger.kernel.org) by vger.kernel.org via listexpand id S1753018AbaDDM0z (ORCPT ); Fri, 4 Apr 2014 08:26:55 -0400 Received: from mail-wi0-f172.google.com ([209.85.212.172]:51251 "EHLO mail-wi0-f172.google.com" rhost-flags-OK-OK-OK-OK) by vger.kernel.org with ESMTP id S1752648AbaDDM0j (ORCPT ); Fri, 4 Apr 2014 08:26:39 -0400 From: Leif Lindholm To: linux-efi@vger.kernel.org, matt.fleming@intel.com Cc: linux-kernel@vger.kernel.org, "H. Peter Anvin" , Roy Franz , Leif Lindholm Subject: [PATCH 3/5] efi: x86: Improve cmdline conversion Date: Fri, 4 Apr 2014 13:25:48 +0100 Message-Id: <1396614350-20889-4-git-send-email-leif.lindholm@linaro.org> X-Mailer: git-send-email 1.7.10.4 In-Reply-To: <1396614350-20889-1-git-send-email-leif.lindholm@linaro.org> References: <1396614350-20889-1-git-send-email-leif.lindholm@linaro.org> Sender: linux-kernel-owner@vger.kernel.org List-ID: X-Mailing-List: linux-kernel@vger.kernel.org From: "H. Peter Anvin" Improve the conversion of the UTF-16 EFI command line to UTF-8 for passing to the kernel. Signed-off-by: Roy Franz Signed-off-by: H. Peter Anvin Signed-off-by: Leif Lindholm --- arch/x86/boot/compressed/eboot.c | 3 +- drivers/firmware/efi/efi-stub-helper.c | 91 ++++++++++++++++++++++++-------- 2 files changed, 70 insertions(+), 24 deletions(-) diff --git a/arch/x86/boot/compressed/eboot.c b/arch/x86/boot/compressed/eboot.c index 1e61461..255d2aa 100644 --- a/arch/x86/boot/compressed/eboot.c +++ b/arch/x86/boot/compressed/eboot.c @@ -1086,8 +1086,7 @@ struct boot_params *make_boot_params(struct efi_config *c) hdr->type_of_loader = 0x21; /* Convert unicode cmdline to ascii */ - cmdline_ptr = efi_convert_cmdline_to_ascii(sys_table, image, - &options_size); + cmdline_ptr = efi_convert_cmdline(sys_table, image, &options_size); if (!cmdline_ptr) goto fail; hdr->cmd_line_ptr = (unsigned long)cmdline_ptr; diff --git a/drivers/firmware/efi/efi-stub-helper.c b/drivers/firmware/efi/efi-stub-helper.c index 61230cb..3cc5ebe 100644 --- a/drivers/firmware/efi/efi-stub-helper.c +++ b/drivers/firmware/efi/efi-stub-helper.c @@ -503,52 +503,99 @@ static efi_status_t efi_relocate_kernel(efi_system_table_t *sys_table_arg, } /* - * Convert the unicode UEFI command line to ASCII to pass to kernel. + * Get the number of UTF-8 bytes corresponding to an UTF-16 character. + * This overestimates for surrogates, but that is okay. + */ +static int efi_utf8_bytes(u16 c) +{ + return 1 + (c >= 0x80) + (c >= 0x800); +} + +/* + * Convert an UTF-16 string, not necessarily null terminated, to UTF-8. + */ +static u8 *efi_utf16_to_utf8(u8 *dst, const u16 *src, int n) +{ + unsigned int c; + + while (n--) { + c = *src++; + if (n && c >= 0xd800 && c <= 0xdbff && + *src >= 0xdc00 && *src <= 0xdfff) { + c = 0x10000 + ((c & 0x3ff) << 10) + (*src & 0x3ff); + src++; + n--; + } + if (c >= 0xd800 && c <= 0xdfff) + c = 0xfffd; /* Unmatched surrogate */ + if (c < 0x80) { + *dst++ = c; + continue; + } + if (c < 0x800) { + *dst++ = 0xc0 + (c >> 6); + goto t1; + } + if (c < 0x10000) { + *dst++ = 0xe0 + (c >> 12); + goto t2; + } + *dst++ = 0xf0 + (c >> 18); + *dst++ = 0x80 + ((c >> 12) & 0x3f); +t2: + *dst++ = 0x80 + ((c >> 6) & 0x3f); +t1: + *dst++ = 0x80 + (c & 0x3f); + } + + return dst; +} + +/* + * Do proper conversion from UTF-16 to UTF-8 * Size of memory allocated return in *cmd_line_len. * Returns NULL on error. */ -static char *efi_convert_cmdline_to_ascii(efi_system_table_t *sys_table_arg, - efi_loaded_image_t *image, - int *cmd_line_len) +static char *efi_convert_cmdline(efi_system_table_t *sys_table_arg, + efi_loaded_image_t *image, + int *cmd_line_len) { - u16 *s2; + const u16 *s2; u8 *s1 = NULL; unsigned long cmdline_addr = 0; - int load_options_size = image->load_options_size / 2; /* ASCII */ - void *options = image->load_options; - int options_size = 0; + int load_options_chars = image->load_options_size / 2; /* UTF-16 */ + const u16 *options = image->load_options; + int options_bytes = 0; /* UTF-8 bytes */ + int options_chars = 0; /* UTF-16 chars */ efi_status_t status; - int i; u16 zero = 0; if (options) { s2 = options; - while (*s2 && *s2 != '\n' && options_size < load_options_size) { - s2++; - options_size++; + while (options_chars < load_options_chars + && *s2 && *s2 != '\n') { + options_bytes += efi_utf8_bytes(*s2++); + options_chars++; } } - if (options_size == 0) { - /* No command line options, so return empty string*/ - options_size = 1; + if (!options_chars) { + /* No command line options, so return empty string */ options = &zero; } - options_size++; /* NUL termination */ + options_bytes++; /* NUL termination */ - status = efi_low_alloc(sys_table_arg, options_size, 0, &cmdline_addr); + status = efi_low_alloc(sys_table_arg, options_bytes, 0, &cmdline_addr); if (status != EFI_SUCCESS) return NULL; s1 = (u8 *)cmdline_addr; - s2 = (u16 *)options; - - for (i = 0; i < options_size - 1; i++) - *s1++ = *s2++; + s2 = (const u16 *)options; + s1 = efi_utf16_to_utf8(s1, s2, options_chars); *s1 = '\0'; - *cmd_line_len = options_size; + *cmd_line_len = options_bytes; return (char *)cmdline_addr; } -- 1.7.10.4 -- To unsubscribe from this list: send the line "unsubscribe linux-kernel" in the body of a message to majordomo@vger.kernel.org More majordomo info at http://vger.kernel.org/majordomo-info.html Please read the FAQ at http://www.tux.org/lkml/