/* * DO NOT ALTER OR REMOVE COPYRIGHT NOTICES OR THIS FILE HEADER. * * This code is free software; you can redistribute it and/or modify it * under the terms of the GNU General Public License version 2 only, as * published by the Free Software Foundation. Oracle designates this * particular file as subject to the "Classpath" exception as provided * by Oracle in the LICENSE file that accompanied this code. * * This code is distributed in the hope that it will be useful, but WITHOUT * ANY WARRANTY; without even the implied warranty of MERCHANTABILITY or * FITNESS FOR A PARTICULAR PURPOSE. See the GNU General Public License * version 2 for more details (a copy is included in the LICENSE file that * accompanied this code). * * You should have received a copy of the GNU General Public License version * 2 along with this work; if not, write to the Free Software Foundation, * Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA. * * Please contact Oracle, 500 Oracle Parkway, Redwood Shores, CA 94065 USA * or visit www.oracle.com if you need additional information or have any * questions. */ /* pngset.c - storage of image information into info struct * * This file is available under and governed by the GNU General Public * License version 2 only, as published by the Free Software Foundation. * However, the following notice accompanied the original version of this * file and, per its terms, should not be removed: * * Last changed in libpng 1.6.26 [October 20, 2016] * Copyright (c) 1998-2016 Glenn Randers-Pehrson * (Version 0.96 Copyright (c) 1996, 1997 Andreas Dilger) * (Version 0.88 Copyright (c) 1995, 1996 Guy Eric Schalnat, Group 42, Inc.) * * This code is released under the libpng license. * For conditions of distribution and use, see the disclaimer * and license in png.h * * The functions here are used during reads to store data from the file * into the info struct, and during writes to store application data * into the info struct for writing into the file. This abstracts the * info struct and allows us to change the structure in the future. */ #include "pngpriv.h" #if defined(PNG_READ_SUPPORTED) || defined(PNG_WRITE_SUPPORTED) #ifdef PNG_bKGD_SUPPORTED void PNGAPI png_set_bKGD(png_const_structrp png_ptr, png_inforp info_ptr, png_const_color_16p background) { png_debug1(1, "in %s storage function", "bKGD"); if (png_ptr == NULL || info_ptr == NULL || background == NULL) return; info_ptr->background = *background; info_ptr->valid |= PNG_INFO_bKGD; } #endif #ifdef PNG_cHRM_SUPPORTED void PNGFAPI png_set_cHRM_fixed(png_const_structrp png_ptr, png_inforp info_ptr, png_fixed_point white_x, png_fixed_point white_y, png_fixed_point red_x, png_fixed_point red_y, png_fixed_point green_x, png_fixed_point green_y, png_fixed_point blue_x, png_fixed_point blue_y) { png_xy xy; png_debug1(1, "in %s storage function", "cHRM fixed"); if (png_ptr == NULL || info_ptr == NULL) return; xy.redx = red_x; xy.redy = red_y; xy.greenx = green_x; xy.greeny = green_y; xy.bluex = blue_x; xy.bluey = blue_y; xy.whitex = white_x; xy.whitey = white_y; if (png_colorspace_set_chromaticities(png_ptr, &info_ptr->colorspace, &xy, 2/* override with app values*/) != 0) info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM; png_colorspace_sync_info(png_ptr, info_ptr); } void PNGFAPI png_set_cHRM_XYZ_fixed(png_const_structrp png_ptr, png_inforp info_ptr, png_fixed_point int_red_X, png_fixed_point int_red_Y, png_fixed_point int_red_Z, png_fixed_point int_green_X, png_fixed_point int_green_Y, png_fixed_point int_green_Z, png_fixed_point int_blue_X, png_fixed_point int_blue_Y, png_fixed_point int_blue_Z) { png_XYZ XYZ; png_debug1(1, "in %s storage function", "cHRM XYZ fixed"); if (png_ptr == NULL || info_ptr == NULL) return; XYZ.red_X = int_red_X; XYZ.red_Y = int_red_Y; XYZ.red_Z = int_red_Z; XYZ.green_X = int_green_X; XYZ.green_Y = int_green_Y; XYZ.green_Z = int_green_Z; XYZ.blue_X = int_blue_X; XYZ.blue_Y = int_blue_Y; XYZ.blue_Z = int_blue_Z; if (png_colorspace_set_endpoints(png_ptr, &info_ptr->colorspace, &XYZ, 2) != 0) info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_cHRM; png_colorspace_sync_info(png_ptr, info_ptr); } # ifdef PNG_FLOATING_POINT_SUPPORTED void PNGAPI png_set_cHRM(png_const_structrp png_ptr, png_inforp info_ptr, double white_x, double white_y, double red_x, double red_y, double green_x, double green_y, double blue_x, double blue_y) { png_set_cHRM_fixed(png_ptr, info_ptr, png_fixed(png_ptr, white_x, "cHRM White X"), png_fixed(png_ptr, white_y, "cHRM White Y"), png_fixed(png_ptr, red_x, "cHRM Red X"), png_fixed(png_ptr, red_y, "cHRM Red Y"), png_fixed(png_ptr, green_x, "cHRM Green X"), png_fixed(png_ptr, green_y, "cHRM Green Y"), png_fixed(png_ptr, blue_x, "cHRM Blue X"), png_fixed(png_ptr, blue_y, "cHRM Blue Y")); } void PNGAPI png_set_cHRM_XYZ(png_const_structrp png_ptr, png_inforp info_ptr, double red_X, double red_Y, double red_Z, double green_X, double green_Y, double green_Z, double blue_X, double blue_Y, double blue_Z) { png_set_cHRM_XYZ_fixed(png_ptr, info_ptr, png_fixed(png_ptr, red_X, "cHRM Red X"), png_fixed(png_ptr, red_Y, "cHRM Red Y"), png_fixed(png_ptr, red_Z, "cHRM Red Z"), png_fixed(png_ptr, green_X, "cHRM Green X"), png_fixed(png_ptr, green_Y, "cHRM Green Y"), png_fixed(png_ptr, green_Z, "cHRM Green Z"), png_fixed(png_ptr, blue_X, "cHRM Blue X"), png_fixed(png_ptr, blue_Y, "cHRM Blue Y"), png_fixed(png_ptr, blue_Z, "cHRM Blue Z")); } # endif /* FLOATING_POINT */ #endif /* cHRM */ #ifdef PNG_gAMA_SUPPORTED void PNGFAPI png_set_gAMA_fixed(png_const_structrp png_ptr, png_inforp info_ptr, png_fixed_point file_gamma) { png_debug1(1, "in %s storage function", "gAMA"); if (png_ptr == NULL || info_ptr == NULL) return; png_colorspace_set_gamma(png_ptr, &info_ptr->colorspace, file_gamma); png_colorspace_sync_info(png_ptr, info_ptr); } # ifdef PNG_FLOATING_POINT_SUPPORTED void PNGAPI png_set_gAMA(png_const_structrp png_ptr, png_inforp info_ptr, double file_gamma) { png_set_gAMA_fixed(png_ptr, info_ptr, png_fixed(png_ptr, file_gamma, "png_set_gAMA")); } # endif #endif #ifdef PNG_hIST_SUPPORTED void PNGAPI png_set_hIST(png_const_structrp png_ptr, png_inforp info_ptr, png_const_uint_16p hist) { int i; png_debug1(1, "in %s storage function", "hIST"); if (png_ptr == NULL || info_ptr == NULL) return; if (info_ptr->num_palette == 0 || info_ptr->num_palette > PNG_MAX_PALETTE_LENGTH) { png_warning(png_ptr, "Invalid palette size, hIST allocation skipped"); return; } png_free_data(png_ptr, info_ptr, PNG_FREE_HIST, 0); /* Changed from info->num_palette to PNG_MAX_PALETTE_LENGTH in * version 1.2.1 */ info_ptr->hist = png_voidcast(png_uint_16p, png_malloc_warn(png_ptr, PNG_MAX_PALETTE_LENGTH * (sizeof (png_uint_16)))); if (info_ptr->hist == NULL) { png_warning(png_ptr, "Insufficient memory for hIST chunk data"); return; } info_ptr->free_me |= PNG_FREE_HIST; for (i = 0; i < info_ptr->num_palette; i++) info_ptr->hist[i] = hist[i]; info_ptr->valid |= PNG_INFO_hIST; } #endif void PNGAPI png_set_IHDR(png_const_structrp png_ptr, png_inforp info_ptr, png_uint_32 width, png_uint_32 height, int bit_depth, int color_type, int interlace_type, int compression_type, int filter_type) { png_debug1(1, "in %s storage function", "IHDR"); if (png_ptr == NULL || info_ptr == NULL) return; info_ptr->width = width; info_ptr->height = height; info_ptr->bit_depth = (png_byte)bit_depth; info_ptr->color_type = (png_byte)color_type; info_ptr->compression_type = (png_byte)compression_type; info_ptr->filter_type = (png_byte)filter_type; info_ptr->interlace_type = (png_byte)interlace_type; png_check_IHDR (png_ptr, info_ptr->width, info_ptr->height, info_ptr->bit_depth, info_ptr->color_type, info_ptr->interlace_type, info_ptr->compression_type, info_ptr->filter_type); if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) info_ptr->channels = 1; else if ((info_ptr->color_type & PNG_COLOR_MASK_COLOR) != 0) info_ptr->channels = 3; else info_ptr->channels = 1; if ((info_ptr->color_type & PNG_COLOR_MASK_ALPHA) != 0) info_ptr->channels++; info_ptr->pixel_depth = (png_byte)(info_ptr->channels * info_ptr->bit_depth); info_ptr->rowbytes = PNG_ROWBYTES(info_ptr->pixel_depth, width); } #ifdef PNG_oFFs_SUPPORTED void PNGAPI png_set_oFFs(png_const_structrp png_ptr, png_inforp info_ptr, png_int_32 offset_x, png_int_32 offset_y, int unit_type) { png_debug1(1, "in %s storage function", "oFFs"); if (png_ptr == NULL || info_ptr == NULL) return; info_ptr->x_offset = offset_x; info_ptr->y_offset = offset_y; info_ptr->offset_unit_type = (png_byte)unit_type; info_ptr->valid |= PNG_INFO_oFFs; } #endif #ifdef PNG_pCAL_SUPPORTED void PNGAPI png_set_pCAL(png_const_structrp png_ptr, png_inforp info_ptr, png_const_charp purpose, png_int_32 X0, png_int_32 X1, int type, int nparams, png_const_charp units, png_charpp params) { png_size_t length; int i; png_debug1(1, "in %s storage function", "pCAL"); if (png_ptr == NULL || info_ptr == NULL || purpose == NULL || units == NULL || (nparams > 0 && params == NULL)) return; length = strlen(purpose) + 1; png_debug1(3, "allocating purpose for info (%lu bytes)", (unsigned long)length); /* TODO: validate format of calibration name and unit name */ /* Check that the type matches the specification. */ if (type < 0 || type > 3) { png_chunk_report(png_ptr, "Invalid pCAL equation type", PNG_CHUNK_WRITE_ERROR); return; } if (nparams < 0 || nparams > 255) { png_chunk_report(png_ptr, "Invalid pCAL parameter count", PNG_CHUNK_WRITE_ERROR); return; } /* Validate params[nparams] */ for (i=0; ipcal_purpose = png_voidcast(png_charp, png_malloc_warn(png_ptr, length)); if (info_ptr->pcal_purpose == NULL) { png_chunk_report(png_ptr, "Insufficient memory for pCAL purpose", PNG_CHUNK_WRITE_ERROR); return; } memcpy(info_ptr->pcal_purpose, purpose, length); png_debug(3, "storing X0, X1, type, and nparams in info"); info_ptr->pcal_X0 = X0; info_ptr->pcal_X1 = X1; info_ptr->pcal_type = (png_byte)type; info_ptr->pcal_nparams = (png_byte)nparams; length = strlen(units) + 1; png_debug1(3, "allocating units for info (%lu bytes)", (unsigned long)length); info_ptr->pcal_units = png_voidcast(png_charp, png_malloc_warn(png_ptr, length)); if (info_ptr->pcal_units == NULL) { png_warning(png_ptr, "Insufficient memory for pCAL units"); return; } memcpy(info_ptr->pcal_units, units, length); info_ptr->pcal_params = png_voidcast(png_charpp, png_malloc_warn(png_ptr, (png_size_t)(((unsigned int)nparams + 1) * (sizeof (png_charp))))); if (info_ptr->pcal_params == NULL) { png_warning(png_ptr, "Insufficient memory for pCAL params"); return; } memset(info_ptr->pcal_params, 0, ((unsigned int)nparams + 1) * (sizeof (png_charp))); for (i = 0; i < nparams; i++) { length = strlen(params[i]) + 1; png_debug2(3, "allocating parameter %d for info (%lu bytes)", i, (unsigned long)length); info_ptr->pcal_params[i] = (png_charp)png_malloc_warn(png_ptr, length); if (info_ptr->pcal_params[i] == NULL) { png_warning(png_ptr, "Insufficient memory for pCAL parameter"); return; } memcpy(info_ptr->pcal_params[i], params[i], length); } info_ptr->valid |= PNG_INFO_pCAL; info_ptr->free_me |= PNG_FREE_PCAL; } #endif #ifdef PNG_sCAL_SUPPORTED void PNGAPI png_set_sCAL_s(png_const_structrp png_ptr, png_inforp info_ptr, int unit, png_const_charp swidth, png_const_charp sheight) { png_size_t lengthw = 0, lengthh = 0; png_debug1(1, "in %s storage function", "sCAL"); if (png_ptr == NULL || info_ptr == NULL) return; /* Double check the unit (should never get here with an invalid * unit unless this is an API call.) */ if (unit != 1 && unit != 2) png_error(png_ptr, "Invalid sCAL unit"); if (swidth == NULL || (lengthw = strlen(swidth)) == 0 || swidth[0] == 45 /* '-' */ || !png_check_fp_string(swidth, lengthw)) png_error(png_ptr, "Invalid sCAL width"); if (sheight == NULL || (lengthh = strlen(sheight)) == 0 || sheight[0] == 45 /* '-' */ || !png_check_fp_string(sheight, lengthh)) png_error(png_ptr, "Invalid sCAL height"); info_ptr->scal_unit = (png_byte)unit; ++lengthw; png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthw); info_ptr->scal_s_width = png_voidcast(png_charp, png_malloc_warn(png_ptr, lengthw)); if (info_ptr->scal_s_width == NULL) { png_warning(png_ptr, "Memory allocation failed while processing sCAL"); return; } memcpy(info_ptr->scal_s_width, swidth, lengthw); ++lengthh; png_debug1(3, "allocating unit for info (%u bytes)", (unsigned int)lengthh); info_ptr->scal_s_height = png_voidcast(png_charp, png_malloc_warn(png_ptr, lengthh)); if (info_ptr->scal_s_height == NULL) { png_free (png_ptr, info_ptr->scal_s_width); info_ptr->scal_s_width = NULL; png_warning(png_ptr, "Memory allocation failed while processing sCAL"); return; } memcpy(info_ptr->scal_s_height, sheight, lengthh); info_ptr->valid |= PNG_INFO_sCAL; info_ptr->free_me |= PNG_FREE_SCAL; } # ifdef PNG_FLOATING_POINT_SUPPORTED void PNGAPI png_set_sCAL(png_const_structrp png_ptr, png_inforp info_ptr, int unit, double width, double height) { png_debug1(1, "in %s storage function", "sCAL"); /* Check the arguments. */ if (width <= 0) png_warning(png_ptr, "Invalid sCAL width ignored"); else if (height <= 0) png_warning(png_ptr, "Invalid sCAL height ignored"); else { /* Convert 'width' and 'height' to ASCII. */ char swidth[PNG_sCAL_MAX_DIGITS+1]; char sheight[PNG_sCAL_MAX_DIGITS+1]; png_ascii_from_fp(png_ptr, swidth, (sizeof swidth), width, PNG_sCAL_PRECISION); png_ascii_from_fp(png_ptr, sheight, (sizeof sheight), height, PNG_sCAL_PRECISION); png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight); } } # endif # ifdef PNG_FIXED_POINT_SUPPORTED void PNGAPI png_set_sCAL_fixed(png_const_structrp png_ptr, png_inforp info_ptr, int unit, png_fixed_point width, png_fixed_point height) { png_debug1(1, "in %s storage function", "sCAL"); /* Check the arguments. */ if (width <= 0) png_warning(png_ptr, "Invalid sCAL width ignored"); else if (height <= 0) png_warning(png_ptr, "Invalid sCAL height ignored"); else { /* Convert 'width' and 'height' to ASCII. */ char swidth[PNG_sCAL_MAX_DIGITS+1]; char sheight[PNG_sCAL_MAX_DIGITS+1]; png_ascii_from_fixed(png_ptr, swidth, (sizeof swidth), width); png_ascii_from_fixed(png_ptr, sheight, (sizeof sheight), height); png_set_sCAL_s(png_ptr, info_ptr, unit, swidth, sheight); } } # endif #endif #ifdef PNG_pHYs_SUPPORTED void PNGAPI png_set_pHYs(png_const_structrp png_ptr, png_inforp info_ptr, png_uint_32 res_x, png_uint_32 res_y, int unit_type) { png_debug1(1, "in %s storage function", "pHYs"); if (png_ptr == NULL || info_ptr == NULL) return; info_ptr->x_pixels_per_unit = res_x; info_ptr->y_pixels_per_unit = res_y; info_ptr->phys_unit_type = (png_byte)unit_type; info_ptr->valid |= PNG_INFO_pHYs; } #endif void PNGAPI png_set_PLTE(png_structrp png_ptr, png_inforp info_ptr, png_const_colorp palette, int num_palette) { png_uint_32 max_palette_length; png_debug1(1, "in %s storage function", "PLTE"); if (png_ptr == NULL || info_ptr == NULL) return; max_palette_length = (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) ? (1 << info_ptr->bit_depth) : PNG_MAX_PALETTE_LENGTH; if (num_palette < 0 || num_palette > (int) max_palette_length) { if (info_ptr->color_type == PNG_COLOR_TYPE_PALETTE) png_error(png_ptr, "Invalid palette length"); else { png_warning(png_ptr, "Invalid palette length"); return; } } if ((num_palette > 0 && palette == NULL) || (num_palette == 0 # ifdef PNG_MNG_FEATURES_SUPPORTED && (png_ptr->mng_features_permitted & PNG_FLAG_MNG_EMPTY_PLTE) == 0 # endif )) { png_error(png_ptr, "Invalid palette"); } /* It may not actually be necessary to set png_ptr->palette here; * we do it for backward compatibility with the way the png_handle_tRNS * function used to do the allocation. * * 1.6.0: the above statement appears to be incorrect; something has to set * the palette inside png_struct on read. */ png_free_data(png_ptr, info_ptr, PNG_FREE_PLTE, 0); /* Changed in libpng-1.2.1 to allocate PNG_MAX_PALETTE_LENGTH instead * of num_palette entries, in case of an invalid PNG file or incorrect * call to png_set_PLTE() with too-large sample values. */ png_ptr->palette = png_voidcast(png_colorp, png_calloc(png_ptr, PNG_MAX_PALETTE_LENGTH * (sizeof (png_color)))); if (num_palette > 0) memcpy(png_ptr->palette, palette, (unsigned int)num_palette * (sizeof (png_color))); info_ptr->palette = png_ptr->palette; info_ptr->num_palette = png_ptr->num_palette = (png_uint_16)num_palette; info_ptr->free_me |= PNG_FREE_PLTE; info_ptr->valid |= PNG_INFO_PLTE; } #ifdef PNG_sBIT_SUPPORTED void PNGAPI png_set_sBIT(png_const_structrp png_ptr, png_inforp info_ptr, png_const_color_8p sig_bit) { png_debug1(1, "in %s storage function", "sBIT"); if (png_ptr == NULL || info_ptr == NULL || sig_bit == NULL) return; info_ptr->sig_bit = *sig_bit; info_ptr->valid |= PNG_INFO_sBIT; } #endif #ifdef PNG_sRGB_SUPPORTED void PNGAPI png_set_sRGB(png_const_structrp png_ptr, png_inforp info_ptr, int srgb_intent) { png_debug1(1, "in %s storage function", "sRGB"); if (png_ptr == NULL || info_ptr == NULL) return; (void)png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent); png_colorspace_sync_info(png_ptr, info_ptr); } void PNGAPI png_set_sRGB_gAMA_and_cHRM(png_const_structrp png_ptr, png_inforp info_ptr, int srgb_intent) { png_debug1(1, "in %s storage function", "sRGB_gAMA_and_cHRM"); if (png_ptr == NULL || info_ptr == NULL) return; if (png_colorspace_set_sRGB(png_ptr, &info_ptr->colorspace, srgb_intent) != 0) { /* This causes the gAMA and cHRM to be written too */ info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM; } png_colorspace_sync_info(png_ptr, info_ptr); } #endif /* sRGB */ #ifdef PNG_iCCP_SUPPORTED void PNGAPI png_set_iCCP(png_const_structrp png_ptr, png_inforp info_ptr, png_const_charp name, int compression_type, png_const_bytep profile, png_uint_32 proflen) { png_charp new_iccp_name; png_bytep new_iccp_profile; png_size_t length; png_debug1(1, "in %s storage function", "iCCP"); if (png_ptr == NULL || info_ptr == NULL || name == NULL || profile == NULL) return; if (compression_type != PNG_COMPRESSION_TYPE_BASE) png_app_error(png_ptr, "Invalid iCCP compression method"); /* Set the colorspace first because this validates the profile; do not * override previously set app cHRM or gAMA here (because likely as not the * application knows better than libpng what the correct values are.) Pass * the info_ptr color_type field to png_colorspace_set_ICC because in the * write case it has not yet been stored in png_ptr. */ { int result = png_colorspace_set_ICC(png_ptr, &info_ptr->colorspace, name, proflen, profile, info_ptr->color_type); png_colorspace_sync_info(png_ptr, info_ptr); /* Don't do any of the copying if the profile was bad, or inconsistent. */ if (result == 0) return; /* But do write the gAMA and cHRM chunks from the profile. */ info_ptr->colorspace.flags |= PNG_COLORSPACE_FROM_gAMA|PNG_COLORSPACE_FROM_cHRM; } length = strlen(name)+1; new_iccp_name = png_voidcast(png_charp, png_malloc_warn(png_ptr, length)); if (new_iccp_name == NULL) { png_benign_error(png_ptr, "Insufficient memory to process iCCP chunk"); return; } memcpy(new_iccp_name, name, length); new_iccp_profile = png_voidcast(png_bytep, png_malloc_warn(png_ptr, proflen)); if (new_iccp_profile == NULL) { png_free(png_ptr, new_iccp_name); png_benign_error(png_ptr, "Insufficient memory to process iCCP profile"); return; } memcpy(new_iccp_profile, profile, proflen); png_free_data(png_ptr, info_ptr, PNG_FREE_ICCP, 0); info_ptr->iccp_proflen = proflen; info_ptr->iccp_name = new_iccp_name; info_ptr->iccp_profile = new_iccp_profile; info_ptr->free_me |= PNG_FREE_ICCP; info_ptr->valid |= PNG_INFO_iCCP; } #endif #ifdef PNG_TEXT_SUPPORTED void PNGAPI png_set_text(png_const_structrp png_ptr, png_inforp info_ptr, png_const_textp text_ptr, int num_text) { int ret; ret = png_set_text_2(png_ptr, info_ptr, text_ptr, num_text); if (ret != 0) png_error(png_ptr, "Insufficient memory to store text"); } int /* PRIVATE */ png_set_text_2(png_const_structrp png_ptr, png_inforp info_ptr, png_const_textp text_ptr, int num_text) { int i; png_debug1(1, "in %lx storage function", png_ptr == NULL ? 0xabadca11U : (unsigned long)png_ptr->chunk_name); if (png_ptr == NULL || info_ptr == NULL || num_text <= 0 || text_ptr == NULL) return(0); /* Make sure we have enough space in the "text" array in info_struct * to hold all of the incoming text_ptr objects. This compare can't overflow * because max_text >= num_text (anyway, subtract of two positive integers * can't overflow in any case.) */ if (num_text > info_ptr->max_text - info_ptr->num_text) { int old_num_text = info_ptr->num_text; int max_text; png_textp new_text = NULL; /* Calculate an appropriate max_text, checking for overflow. */ max_text = old_num_text; if (num_text <= INT_MAX - max_text) { max_text += num_text; /* Round up to a multiple of 8 */ if (max_text < INT_MAX-8) max_text = (max_text + 8) & ~0x7; else max_text = INT_MAX; /* Now allocate a new array and copy the old members in; this does all * the overflow checks. */ new_text = png_voidcast(png_textp,png_realloc_array(png_ptr, info_ptr->text, old_num_text, max_text-old_num_text, sizeof *new_text)); } if (new_text == NULL) { png_chunk_report(png_ptr, "too many text chunks", PNG_CHUNK_WRITE_ERROR); return 1; } png_free(png_ptr, info_ptr->text); info_ptr->text = new_text; info_ptr->free_me |= PNG_FREE_TEXT; info_ptr->max_text = max_text; /* num_text is adjusted below as the entries are copied in */ png_debug1(3, "allocated %d entries for info_ptr->text", max_text); } for (i = 0; i < num_text; i++) { size_t text_length, key_len; size_t lang_len, lang_key_len; png_textp textp = &(info_ptr->text[info_ptr->num_text]); if (text_ptr[i].key == NULL) continue; if (text_ptr[i].compression < PNG_TEXT_COMPRESSION_NONE || text_ptr[i].compression >= PNG_TEXT_COMPRESSION_LAST) { png_chunk_report(png_ptr, "text compression mode is out of range", PNG_CHUNK_WRITE_ERROR); continue; } key_len = strlen(text_ptr[i].key); if (text_ptr[i].compression <= 0) { lang_len = 0; lang_key_len = 0; } else # ifdef PNG_iTXt_SUPPORTED { /* Set iTXt data */ if (text_ptr[i].lang != NULL) lang_len = strlen(text_ptr[i].lang); else lang_len = 0; if (text_ptr[i].lang_key != NULL) lang_key_len = strlen(text_ptr[i].lang_key); else lang_key_len = 0; } # else /* iTXt */ { png_chunk_report(png_ptr, "iTXt chunk not supported", PNG_CHUNK_WRITE_ERROR); continue; } # endif if (text_ptr[i].text == NULL || text_ptr[i].text[0] == '\0') { text_length = 0; # ifdef PNG_iTXt_SUPPORTED if (text_ptr[i].compression > 0) textp->compression = PNG_ITXT_COMPRESSION_NONE; else # endif textp->compression = PNG_TEXT_COMPRESSION_NONE; } else { text_length = strlen(text_ptr[i].text); textp->compression = text_ptr[i].compression; } textp->key = png_voidcast(png_charp,png_malloc_base(png_ptr, key_len + text_length + lang_len + lang_key_len + 4)); if (textp->key == NULL) { png_chunk_report(png_ptr, "text chunk: out of memory", PNG_CHUNK_WRITE_ERROR); return 1; } png_debug2(2, "Allocated %lu bytes at %p in png_set_text", (unsigned long)(png_uint_32) (key_len + lang_len + lang_key_len + text_length + 4), textp->key); memcpy(textp->key, text_ptr[i].key, key_len); *(textp->key + key_len) = '\0'; if (text_ptr[i].compression > 0) { textp->lang = textp->key + key_len + 1; memcpy(textp->lang, text_ptr[i].lang, lang_len); *(textp->lang + lang_len) = '\0'; textp->lang_key = textp->lang + lang_len + 1; memcpy(textp->lang_key, text_ptr[i].lang_key, lang_key_len); *(textp->lang_key + lang_key_len) = '\0'; textp->text = textp->lang_key + lang_key_len + 1; } else { textp->lang=NULL; textp->lang_key=NULL; textp->text = textp->key + key_len + 1; } if (text_length != 0) memcpy(textp->text, text_ptr[i].text, text_length); *(textp->text + text_length) = '\0'; # ifdef PNG_iTXt_SUPPORTED if (textp->compression > 0) { textp->text_length = 0; textp->itxt_length = text_length; } else # endif { textp->text_length = text_length; textp->itxt_length = 0; } info_ptr->num_text++; png_debug1(3, "transferred text chunk %d", info_ptr->num_text); } return(0); } #endif #ifdef PNG_tIME_SUPPORTED void PNGAPI png_set_tIME(png_const_structrp png_ptr, png_inforp info_ptr, png_const_timep mod_time) { png_debug1(1, "in %s storage function", "tIME"); if (png_ptr == NULL || info_ptr == NULL || mod_time == NULL || (png_ptr->mode & PNG_WROTE_tIME) != 0) return; if (mod_time->month == 0 || mod_time->month > 12 || mod_time->day == 0 || mod_time->day > 31 || mod_time->hour > 23 || mod_time->minute > 59 || mod_time->second > 60) { png_warning(png_ptr, "Ignoring invalid time value"); return; } info_ptr->mod_time = *mod_time; info_ptr->valid |= PNG_INFO_tIME; } #endif #ifdef PNG_tRNS_SUPPORTED void PNGAPI png_set_tRNS(png_structrp png_ptr, png_inforp info_ptr, png_const_bytep trans_alpha, int num_trans, png_const_color_16p trans_color) { png_debug1(1, "in %s storage function", "tRNS"); if (png_ptr == NULL || info_ptr == NULL) return; if (trans_alpha != NULL) { /* It may not actually be necessary to set png_ptr->trans_alpha here; * we do it for backward compatibility with the way the png_handle_tRNS * function used to do the allocation. * * 1.6.0: The above statement is incorrect; png_handle_tRNS effectively * relies on png_set_tRNS storing the information in png_struct * (otherwise it won't be there for the code in pngrtran.c). */ png_free_data(png_ptr, info_ptr, PNG_FREE_TRNS, 0); if (num_trans > 0 && num_trans <= PNG_MAX_PALETTE_LENGTH) { /* Changed from num_trans to PNG_MAX_PALETTE_LENGTH in version 1.2.1 */ info_ptr->trans_alpha = png_voidcast(png_bytep, png_malloc(png_ptr, PNG_MAX_PALETTE_LENGTH)); memcpy(info_ptr->trans_alpha, trans_alpha, (png_size_t)num_trans); } png_ptr->trans_alpha = info_ptr->trans_alpha; } if (trans_color != NULL) { #ifdef PNG_WARNINGS_SUPPORTED if (info_ptr->bit_depth < 16) { int sample_max = (1 << info_ptr->bit_depth) - 1; if ((info_ptr->color_type == PNG_COLOR_TYPE_GRAY && trans_color->gray > sample_max) || (info_ptr->color_type == PNG_COLOR_TYPE_RGB && (trans_color->red > sample_max || trans_color->green > sample_max || trans_color->blue > sample_max))) png_warning(png_ptr, "tRNS chunk has out-of-range samples for bit_depth"); } #endif info_ptr->trans_color = *trans_color; if (num_trans == 0) num_trans = 1; } info_ptr->num_trans = (png_uint_16)num_trans; if (num_trans != 0) { info_ptr->valid |= PNG_INFO_tRNS; info_ptr->free_me |= PNG_FREE_TRNS; } } #endif #ifdef PNG_sPLT_SUPPORTED void PNGAPI png_set_sPLT(png_const_structrp png_ptr, png_inforp info_ptr, png_const_sPLT_tp entries, int nentries) /* * entries - array of png_sPLT_t structures * to be added to the list of palettes * in the info structure. * * nentries - number of palette structures to be * added. */ { png_sPLT_tp np; if (png_ptr == NULL || info_ptr == NULL || nentries <= 0 || entries == NULL) return; /* Use the internal realloc function, which checks for all the possible * overflows. Notice that the parameters are (int) and (size_t) */ np = png_voidcast(png_sPLT_tp,png_realloc_array(png_ptr, info_ptr->splt_palettes, info_ptr->splt_palettes_num, nentries, sizeof *np)); if (np == NULL) { /* Out of memory or too many chunks */ png_chunk_report(png_ptr, "too many sPLT chunks", PNG_CHUNK_WRITE_ERROR); return; } png_free(png_ptr, info_ptr->splt_palettes); info_ptr->splt_palettes = np; info_ptr->free_me |= PNG_FREE_SPLT; np += info_ptr->splt_palettes_num; do { png_size_t length; /* Skip invalid input entries */ if (entries->name == NULL || entries->entries == NULL) { /* png_handle_sPLT doesn't do this, so this is an app error */ png_app_error(png_ptr, "png_set_sPLT: invalid sPLT"); /* Just skip the invalid entry */ continue; } np->depth = entries->depth; /* In the event of out-of-memory just return - there's no point keeping * on trying to add sPLT chunks. */ length = strlen(entries->name) + 1; np->name = png_voidcast(png_charp, png_malloc_base(png_ptr, length)); if (np->name == NULL) break; memcpy(np->name, entries->name, length); /* IMPORTANT: we have memory now that won't get freed if something else * goes wrong; this code must free it. png_malloc_array produces no * warnings; use a png_chunk_report (below) if there is an error. */ np->entries = png_voidcast(png_sPLT_entryp, png_malloc_array(png_ptr, entries->nentries, sizeof (png_sPLT_entry))); if (np->entries == NULL) { png_free(png_ptr, np->name); np->name = NULL; break; } np->nentries = entries->nentries; /* This multiply can't overflow because png_malloc_array has already * checked it when doing the allocation. */ memcpy(np->entries, entries->entries, (unsigned int)entries->nentries * sizeof (png_sPLT_entry)); /* Note that 'continue' skips the advance of the out pointer and out * count, so an invalid entry is not added. */ info_ptr->valid |= PNG_INFO_sPLT; ++(info_ptr->splt_palettes_num); ++np; } while (++entries, --nentries); if (nentries > 0) png_chunk_report(png_ptr, "sPLT out of memory", PNG_CHUNK_WRITE_ERROR); } #endif /* sPLT */ #ifdef PNG_STORE_UNKNOWN_CHUNKS_SUPPORTED static png_byte check_location(png_const_structrp png_ptr, int location) { location &= (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT); /* New in 1.6.0; copy the location and check it. This is an API * change; previously the app had to use the * png_set_unknown_chunk_location API below for each chunk. */ if (location == 0 && (png_ptr->mode & PNG_IS_READ_STRUCT) == 0) { /* Write struct, so unknown chunks come from the app */ png_app_warning(png_ptr, "png_set_unknown_chunks now expects a valid location"); /* Use the old behavior */ location = (png_byte)(png_ptr->mode & (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT)); } /* This need not be an internal error - if the app calls * png_set_unknown_chunks on a read pointer it must get the location right. */ if (location == 0) png_error(png_ptr, "invalid location in png_set_unknown_chunks"); /* Now reduce the location to the top-most set bit by removing each least * significant bit in turn. */ while (location != (location & -location)) location &= ~(location & -location); /* The cast is safe because 'location' is a bit mask and only the low four * bits are significant. */ return (png_byte)location; } void PNGAPI png_set_unknown_chunks(png_const_structrp png_ptr, png_inforp info_ptr, png_const_unknown_chunkp unknowns, int num_unknowns) { png_unknown_chunkp np; if (png_ptr == NULL || info_ptr == NULL || num_unknowns <= 0 || unknowns == NULL) return; /* Check for the failure cases where support has been disabled at compile * time. This code is hardly ever compiled - it's here because * STORE_UNKNOWN_CHUNKS is set by both read and write code (compiling in this * code) but may be meaningless if the read or write handling of unknown * chunks is not compiled in. */ # if !defined(PNG_READ_UNKNOWN_CHUNKS_SUPPORTED) && \ defined(PNG_READ_SUPPORTED) if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0) { png_app_error(png_ptr, "no unknown chunk support on read"); return; } # endif # if !defined(PNG_WRITE_UNKNOWN_CHUNKS_SUPPORTED) && \ defined(PNG_WRITE_SUPPORTED) if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0) { png_app_error(png_ptr, "no unknown chunk support on write"); return; } # endif /* Prior to 1.6.0 this code used png_malloc_warn; however, this meant that * unknown critical chunks could be lost with just a warning resulting in * undefined behavior. Now png_chunk_report is used to provide behavior * appropriate to read or write. */ np = png_voidcast(png_unknown_chunkp, png_realloc_array(png_ptr, info_ptr->unknown_chunks, info_ptr->unknown_chunks_num, num_unknowns, sizeof *np)); if (np == NULL) { png_chunk_report(png_ptr, "too many unknown chunks", PNG_CHUNK_WRITE_ERROR); return; } png_free(png_ptr, info_ptr->unknown_chunks); info_ptr->unknown_chunks = np; /* safe because it is initialized */ info_ptr->free_me |= PNG_FREE_UNKN; np += info_ptr->unknown_chunks_num; /* Increment unknown_chunks_num each time round the loop to protect the * just-allocated chunk data. */ for (; num_unknowns > 0; --num_unknowns, ++unknowns) { memcpy(np->name, unknowns->name, (sizeof np->name)); np->name[(sizeof np->name)-1] = '\0'; np->location = check_location(png_ptr, unknowns->location); if (unknowns->size == 0) { np->data = NULL; np->size = 0; } else { np->data = png_voidcast(png_bytep, png_malloc_base(png_ptr, unknowns->size)); if (np->data == NULL) { png_chunk_report(png_ptr, "unknown chunk: out of memory", PNG_CHUNK_WRITE_ERROR); /* But just skip storing the unknown chunk */ continue; } memcpy(np->data, unknowns->data, unknowns->size); np->size = unknowns->size; } /* These increments are skipped on out-of-memory for the data - the * unknown chunk entry gets overwritten if the png_chunk_report returns. * This is correct in the read case (the chunk is just dropped.) */ ++np; ++(info_ptr->unknown_chunks_num); } } void PNGAPI png_set_unknown_chunk_location(png_const_structrp png_ptr, png_inforp info_ptr, int chunk, int location) { /* This API is pretty pointless in 1.6.0 because the location can be set * before the call to png_set_unknown_chunks. * * TODO: add a png_app_warning in 1.7 */ if (png_ptr != NULL && info_ptr != NULL && chunk >= 0 && chunk < info_ptr->unknown_chunks_num) { if ((location & (PNG_HAVE_IHDR|PNG_HAVE_PLTE|PNG_AFTER_IDAT)) == 0) { png_app_error(png_ptr, "invalid unknown chunk location"); /* Fake out the pre 1.6.0 behavior: */ if (((unsigned int)location & PNG_HAVE_IDAT) != 0) /* undocumented! */ location = PNG_AFTER_IDAT; else location = PNG_HAVE_IHDR; /* also undocumented */ } info_ptr->unknown_chunks[chunk].location = check_location(png_ptr, location); } } #endif /* STORE_UNKNOWN_CHUNKS */ #ifdef PNG_MNG_FEATURES_SUPPORTED png_uint_32 PNGAPI png_permit_mng_features (png_structrp png_ptr, png_uint_32 mng_features) { png_debug(1, "in png_permit_mng_features"); if (png_ptr == NULL) return 0; png_ptr->mng_features_permitted = mng_features & PNG_ALL_MNG_FEATURES; return png_ptr->mng_features_permitted; } #endif #ifdef PNG_HANDLE_AS_UNKNOWN_SUPPORTED static unsigned int add_one_chunk(png_bytep list, unsigned int count, png_const_bytep add, int keep) { unsigned int i; /* Utility function: update the 'keep' state of a chunk if it is already in * the list, otherwise add it to the list. */ for (i=0; i= PNG_HANDLE_CHUNK_LAST) { png_app_error(png_ptr, "png_set_keep_unknown_chunks: invalid keep"); return; } if (num_chunks_in <= 0) { png_ptr->unknown_default = keep; /* '0' means just set the flags, so stop here */ if (num_chunks_in == 0) return; } if (num_chunks_in < 0) { /* Ignore all unknown chunks and all chunks recognized by * libpng except for IHDR, PLTE, tRNS, IDAT, and IEND */ static PNG_CONST png_byte chunks_to_ignore[] = { 98, 75, 71, 68, '\0', /* bKGD */ 99, 72, 82, 77, '\0', /* cHRM */ 103, 65, 77, 65, '\0', /* gAMA */ 104, 73, 83, 84, '\0', /* hIST */ 105, 67, 67, 80, '\0', /* iCCP */ 105, 84, 88, 116, '\0', /* iTXt */ 111, 70, 70, 115, '\0', /* oFFs */ 112, 67, 65, 76, '\0', /* pCAL */ 112, 72, 89, 115, '\0', /* pHYs */ 115, 66, 73, 84, '\0', /* sBIT */ 115, 67, 65, 76, '\0', /* sCAL */ 115, 80, 76, 84, '\0', /* sPLT */ 115, 84, 69, 82, '\0', /* sTER */ 115, 82, 71, 66, '\0', /* sRGB */ 116, 69, 88, 116, '\0', /* tEXt */ 116, 73, 77, 69, '\0', /* tIME */ 122, 84, 88, 116, '\0' /* zTXt */ }; chunk_list = chunks_to_ignore; num_chunks = (unsigned int)/*SAFE*/(sizeof chunks_to_ignore)/5U; } else /* num_chunks_in > 0 */ { if (chunk_list == NULL) { /* Prior to 1.6.0 this was silently ignored, now it is an app_error * which can be switched off. */ png_app_error(png_ptr, "png_set_keep_unknown_chunks: no chunk list"); return; } num_chunks = (unsigned int)num_chunks_in; } old_num_chunks = png_ptr->num_chunk_list; if (png_ptr->chunk_list == NULL) old_num_chunks = 0; /* Since num_chunks is always restricted to UINT_MAX/5 this can't overflow. */ if (num_chunks + old_num_chunks > UINT_MAX/5) { png_app_error(png_ptr, "png_set_keep_unknown_chunks: too many chunks"); return; } /* If these chunks are being reset to the default then no more memory is * required because add_one_chunk above doesn't extend the list if the 'keep' * parameter is the default. */ if (keep != 0) { new_list = png_voidcast(png_bytep, png_malloc(png_ptr, 5 * (num_chunks + old_num_chunks))); if (old_num_chunks > 0) memcpy(new_list, png_ptr->chunk_list, 5*old_num_chunks); } else if (old_num_chunks > 0) new_list = png_ptr->chunk_list; else new_list = NULL; /* Add the new chunks together with each one's handling code. If the chunk * already exists the code is updated, otherwise the chunk is added to the * end. (In libpng 1.6.0 order no longer matters because this code enforces * the earlier convention that the last setting is the one that is used.) */ if (new_list != NULL) { png_const_bytep inlist; png_bytep outlist; unsigned int i; for (i=0; ichunk_list != new_list) png_free(png_ptr, new_list); new_list = NULL; } } else num_chunks = 0; png_ptr->num_chunk_list = num_chunks; if (png_ptr->chunk_list != new_list) { if (png_ptr->chunk_list != NULL) png_free(png_ptr, png_ptr->chunk_list); png_ptr->chunk_list = new_list; } } #endif #ifdef PNG_READ_USER_CHUNKS_SUPPORTED void PNGAPI png_set_read_user_chunk_fn(png_structrp png_ptr, png_voidp user_chunk_ptr, png_user_chunk_ptr read_user_chunk_fn) { png_debug(1, "in png_set_read_user_chunk_fn"); if (png_ptr == NULL) return; png_ptr->read_user_chunk_fn = read_user_chunk_fn; png_ptr->user_chunk_ptr = user_chunk_ptr; } #endif #ifdef PNG_INFO_IMAGE_SUPPORTED void PNGAPI png_set_rows(png_const_structrp png_ptr, png_inforp info_ptr, png_bytepp row_pointers) { png_debug1(1, "in %s storage function", "rows"); if (png_ptr == NULL || info_ptr == NULL) return; if (info_ptr->row_pointers != NULL && (info_ptr->row_pointers != row_pointers)) png_free_data(png_ptr, info_ptr, PNG_FREE_ROWS, 0); info_ptr->row_pointers = row_pointers; if (row_pointers != NULL) info_ptr->valid |= PNG_INFO_IDAT; } #endif void PNGAPI png_set_compression_buffer_size(png_structrp png_ptr, png_size_t size) { if (png_ptr == NULL) return; if (size == 0 || size > PNG_UINT_31_MAX) png_error(png_ptr, "invalid compression buffer size"); # ifdef PNG_SEQUENTIAL_READ_SUPPORTED if ((png_ptr->mode & PNG_IS_READ_STRUCT) != 0) { png_ptr->IDAT_read_size = (png_uint_32)size; /* checked above */ return; } # endif # ifdef PNG_WRITE_SUPPORTED if ((png_ptr->mode & PNG_IS_READ_STRUCT) == 0) { if (png_ptr->zowner != 0) { png_warning(png_ptr, "Compression buffer size cannot be changed because it is in use"); return; } #ifndef __COVERITY__ /* Some compilers complain that this is always false. However, it * can be true when integer overflow happens. */ if (size > ZLIB_IO_MAX) { png_warning(png_ptr, "Compression buffer size limited to system maximum"); size = ZLIB_IO_MAX; /* must fit */ } #endif if (size < 6) { /* Deflate will potentially go into an infinite loop on a SYNC_FLUSH * if this is permitted. */ png_warning(png_ptr, "Compression buffer size cannot be reduced below 6"); return; } if (png_ptr->zbuffer_size != size) { png_free_buffer_list(png_ptr, &png_ptr->zbuffer_list); png_ptr->zbuffer_size = (uInt)size; } } # endif } void PNGAPI png_set_invalid(png_const_structrp png_ptr, png_inforp info_ptr, int mask) { if (png_ptr != NULL && info_ptr != NULL) info_ptr->valid &= (unsigned int)(~mask); } #ifdef PNG_SET_USER_LIMITS_SUPPORTED /* This function was added to libpng 1.2.6 */ void PNGAPI png_set_user_limits (png_structrp png_ptr, png_uint_32 user_width_max, png_uint_32 user_height_max) { /* Images with dimensions larger than these limits will be * rejected by png_set_IHDR(). To accept any PNG datastream * regardless of dimensions, set both limits to 0x7fffffff. */ if (png_ptr == NULL) return; png_ptr->user_width_max = user_width_max; png_ptr->user_height_max = user_height_max; } /* This function was added to libpng 1.4.0 */ void PNGAPI png_set_chunk_cache_max (png_structrp png_ptr, png_uint_32 user_chunk_cache_max) { if (png_ptr != NULL) png_ptr->user_chunk_cache_max = user_chunk_cache_max; } /* This function was added to libpng 1.4.1 */ void PNGAPI png_set_chunk_malloc_max (png_structrp png_ptr, png_alloc_size_t user_chunk_malloc_max) { if (png_ptr != NULL) png_ptr->user_chunk_malloc_max = user_chunk_malloc_max; } #endif /* ?SET_USER_LIMITS */ #ifdef PNG_BENIGN_ERRORS_SUPPORTED void PNGAPI png_set_benign_errors(png_structrp png_ptr, int allowed) { png_debug(1, "in png_set_benign_errors"); /* If allowed is 1, png_benign_error() is treated as a warning. * * If allowed is 0, png_benign_error() is treated as an error (which * is the default behavior if png_set_benign_errors() is not called). */ if (allowed != 0) png_ptr->flags |= PNG_FLAG_BENIGN_ERRORS_WARN | PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN; else png_ptr->flags &= ~(PNG_FLAG_BENIGN_ERRORS_WARN | PNG_FLAG_APP_WARNINGS_WARN | PNG_FLAG_APP_ERRORS_WARN); } #endif /* BENIGN_ERRORS */ #ifdef PNG_CHECK_FOR_INVALID_INDEX_SUPPORTED /* Whether to report invalid palette index; added at libng-1.5.10. * It is possible for an indexed (color-type==3) PNG file to contain * pixels with invalid (out-of-range) indexes if the PLTE chunk has * fewer entries than the image's bit-depth would allow. We recover * from this gracefully by filling any incomplete palette with zeros * (opaque black). By default, when this occurs libpng will issue * a benign error. This API can be used to override that behavior. */ void PNGAPI png_set_check_for_invalid_index(png_structrp png_ptr, int allowed) { png_debug(1, "in png_set_check_for_invalid_index"); if (allowed > 0) png_ptr->num_palette_max = 0; else png_ptr->num_palette_max = -1; } #endif #if defined(PNG_TEXT_SUPPORTED) || defined(PNG_pCAL_SUPPORTED) || \ defined(PNG_iCCP_SUPPORTED) || defined(PNG_sPLT_SUPPORTED) /* Check that the tEXt or zTXt keyword is valid per PNG 1.0 specification, * and if invalid, correct the keyword rather than discarding the entire * chunk. The PNG 1.0 specification requires keywords 1-79 characters in * length, forbids leading or trailing whitespace, multiple internal spaces, * and the non-break space (0x80) from ISO 8859-1. Returns keyword length. * * The 'new_key' buffer must be 80 characters in size (for the keyword plus a * trailing '\0'). If this routine returns 0 then there was no keyword, or a * valid one could not be generated, and the caller must png_error. */ png_uint_32 /* PRIVATE */ png_check_keyword(png_structrp png_ptr, png_const_charp key, png_bytep new_key) { #ifdef PNG_WARNINGS_SUPPORTED png_const_charp orig_key = key; #endif png_uint_32 key_len = 0; int bad_character = 0; int space = 1; png_debug(1, "in png_check_keyword"); if (key == NULL) { *new_key = 0; return 0; } while (*key && key_len < 79) { png_byte ch = (png_byte)*key++; if ((ch > 32 && ch <= 126) || (ch >= 161 /*&& ch <= 255*/)) *new_key++ = ch, ++key_len, space = 0; else if (space == 0) { /* A space or an invalid character when one wasn't seen immediately * before; output just a space. */ *new_key++ = 32, ++key_len, space = 1; /* If the character was not a space then it is invalid. */ if (ch != 32) bad_character = ch; } else if (bad_character == 0) bad_character = ch; /* just skip it, record the first error */ } if (key_len > 0 && space != 0) /* trailing space */ { --key_len, --new_key; if (bad_character == 0) bad_character = 32; } /* Terminate the keyword */ *new_key = 0; if (key_len == 0) return 0; #ifdef PNG_WARNINGS_SUPPORTED /* Try to only output one warning per keyword: */ if (*key != 0) /* keyword too long */ png_warning(png_ptr, "keyword truncated"); else if (bad_character != 0) { PNG_WARNING_PARAMETERS(p) png_warning_parameter(p, 1, orig_key); png_warning_parameter_signed(p, 2, PNG_NUMBER_FORMAT_02x, bad_character); png_formatted_warning(png_ptr, p, "keyword \"@1\": bad character '0x@2'"); } #else /* !WARNINGS */ PNG_UNUSED(png_ptr) #endif /* !WARNINGS */ return key_len; } #endif /* TEXT || pCAL || iCCP || sPLT */ #endif /* READ || WRITE */