diff options
| -rw-r--r-- | common/fdt_region.c | 657 | ||||
| -rw-r--r-- | common/image-fit-sig.c | 1 | ||||
| -rw-r--r-- | include/fdt_region.h | 304 | ||||
| -rw-r--r-- | include/linux/libfdt.h | 299 | ||||
| -rw-r--r-- | tools/fdtgrep.c | 1 | ||||
| -rw-r--r-- | tools/image-host.c | 1 |
6 files changed, 964 insertions, 299 deletions
diff --git a/common/fdt_region.c b/common/fdt_region.c new file mode 100644 index 0000000000..bf0a9be730 --- /dev/null +++ b/common/fdt_region.c @@ -0,0 +1,657 @@ +// SPDX-License-Identifier: GPL-2.0+ OR BSD-2-Clause +/* + * libfdt - Flat Device Tree manipulation + * Copyright (C) 2013 Google, Inc + * Written by Simon Glass <sjg@chromium.org> + */ + +#include <linux/libfdt_env.h> +#include <fdt_region.h> + +#ifndef USE_HOSTCC +#include <fdt.h> +#include <linux/libfdt.h> +#else +#include "fdt_host.h" +#endif + +#define FDT_MAX_DEPTH 32 + +static int str_in_list(const char *str, char * const list[], int count) +{ + int i; + + for (i = 0; i < count; i++) + if (!strcmp(list[i], str)) + return 1; + + return 0; +} + +int fdt_find_regions(const void *fdt, char * const inc[], int inc_count, + char * const exc_prop[], int exc_prop_count, + struct fdt_region region[], int max_regions, + char *path, int path_len, int add_string_tab) +{ + int stack[FDT_MAX_DEPTH] = { 0 }; + char *end; + int nextoffset = 0; + uint32_t tag; + int count = 0; + int start = -1; + int depth = -1; + int want = 0; + int base = fdt_off_dt_struct(fdt); + + end = path; + *end = '\0'; + do { + const struct fdt_property *prop; + const char *name; + const char *str; + int include = 0; + int stop_at = 0; + int offset; + int len; + + offset = nextoffset; + tag = fdt_next_tag(fdt, offset, &nextoffset); + stop_at = nextoffset; + + switch (tag) { + case FDT_PROP: + include = want >= 2; + stop_at = offset; + prop = fdt_get_property_by_offset(fdt, offset, NULL); + str = fdt_string(fdt, fdt32_to_cpu(prop->nameoff)); + if (str_in_list(str, exc_prop, exc_prop_count)) + include = 0; + break; + + case FDT_NOP: + include = want >= 2; + stop_at = offset; + break; + + case FDT_BEGIN_NODE: + depth++; + if (depth == FDT_MAX_DEPTH) + return -FDT_ERR_BADSTRUCTURE; + name = fdt_get_name(fdt, offset, &len); + if (end - path + 2 + len >= path_len) + return -FDT_ERR_NOSPACE; + if (end != path + 1) + *end++ = '/'; + strcpy(end, name); + end += len; + stack[depth] = want; + if (want == 1) + stop_at = offset; + if (str_in_list(path, inc, inc_count)) + want = 2; + else if (want) + want--; + else + stop_at = offset; + include = want; + break; + + case FDT_END_NODE: + /* Depth must never go below -1 */ + if (depth < 0) + return -FDT_ERR_BADSTRUCTURE; + include = want; + want = stack[depth--]; + while (end > path && *--end != '/') + ; + *end = '\0'; + break; + + case FDT_END: + include = 1; + break; + } + + if (include && start == -1) { + /* Should we merge with previous? */ + if (count && count <= max_regions && + offset == region[count - 1].offset + + region[count - 1].size - base) + start = region[--count].offset - base; + else + start = offset; + } + + if (!include && start != -1) { + if (count < max_regions) { + region[count].offset = base + start; + region[count].size = stop_at - start; + } + count++; + start = -1; + } + } while (tag != FDT_END); + + if (nextoffset != fdt_size_dt_struct(fdt)) + return -FDT_ERR_BADLAYOUT; + + /* Add a region for the END tag and the string table */ + if (count < max_regions) { + region[count].offset = base + start; + region[count].size = nextoffset - start; + if (add_string_tab) + region[count].size += fdt_size_dt_strings(fdt); + } + count++; + + return count; +} + +/** + * fdt_add_region() - Add a new region to our list + * @info: State information + * @offset: Start offset of region + * @size: Size of region + * + * The region is added if there is space, but in any case we increment the + * count. If permitted, and the new region overlaps the last one, we merge + * them. + */ +static int fdt_add_region(struct fdt_region_state *info, int offset, int size) +{ + struct fdt_region *reg; + + reg = info->region ? &info->region[info->count - 1] : NULL; + if (info->can_merge && info->count && + info->count <= info->max_regions && + reg && offset <= reg->offset + reg->size) { + reg->size = offset + size - reg->offset; + } else if (info->count++ < info->max_regions) { + if (reg) { + reg++; + reg->offset = offset; + reg->size = size; + } + } else { + return -1; + } + + return 0; +} + +static int region_list_contains_offset(struct fdt_region_state *info, + const void *fdt, int target) +{ + struct fdt_region *reg; + int num; + + target += fdt_off_dt_struct(fdt); + for (reg = info->region, num = 0; num < info->count; reg++, num++) { + if (target >= reg->offset && target < reg->offset + reg->size) + return 1; + } + + return 0; +} + +/** + * fdt_add_alias_regions() - Add regions covering the aliases that we want + * + * The /aliases node is not automatically included by fdtgrep unless the + * command-line arguments cause to be included (or not excluded). However + * aliases are special in that we generally want to include those which + * reference a node that fdtgrep includes. + * + * In fact we want to include only aliases for those nodes still included in + * the fdt, and drop the other aliases since they point to nodes that will not + * be present. + * + * This function scans the aliases and adds regions for those which we want + * to keep. + * + * @fdt: Device tree to scan + * @region: List of regions + * @count: Number of regions in the list so far (i.e. starting point for this + * function) + * @max_regions: Maximum number of regions in @region list + * @info: Place to put the region state + * @return number of regions after processing, or -FDT_ERR_NOSPACE if we did + * not have enough room in the regions table for the regions we wanted to add. + */ +int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count, + int max_regions, struct fdt_region_state *info) +{ + int base = fdt_off_dt_struct(fdt); + int node, node_end, offset; + int did_alias_header; + + node = fdt_subnode_offset(fdt, 0, "aliases"); + if (node < 0) + return -FDT_ERR_NOTFOUND; + + /* + * Find the next node so that we know where the /aliases node ends. We + * need special handling if /aliases is the last node. + */ + node_end = fdt_next_subnode(fdt, node); + if (node_end == -FDT_ERR_NOTFOUND) + /* Move back to the FDT_END_NODE tag of '/' */ + node_end = fdt_size_dt_struct(fdt) - sizeof(fdt32_t) * 2; + else if (node_end < 0) /* other error */ + return node_end; + node_end -= sizeof(fdt32_t); /* Move to FDT_END_NODE tag of /aliases */ + + did_alias_header = 0; + info->region = region; + info->count = count; + info->can_merge = 0; + info->max_regions = max_regions; + + for (offset = fdt_first_property_offset(fdt, node); + offset >= 0; + offset = fdt_next_property_offset(fdt, offset)) { + const struct fdt_property *prop; + const char *name; + int target, next; + + prop = fdt_get_property_by_offset(fdt, offset, NULL); + name = fdt_string(fdt, fdt32_to_cpu(prop->nameoff)); + target = fdt_path_offset(fdt, name); + if (!region_list_contains_offset(info, fdt, target)) + continue; + next = fdt_next_property_offset(fdt, offset); + if (next < 0) + next = node_end; + + if (!did_alias_header) { + fdt_add_region(info, base + node, 12); + did_alias_header = 1; + } + fdt_add_region(info, base + offset, next - offset); + } + + /* Add the FDT_END_NODE tag */ + if (did_alias_header) + fdt_add_region(info, base + node_end, sizeof(fdt32_t)); + + return info->count < max_regions ? info->count : -FDT_ERR_NOSPACE; +} + +/** + * fdt_include_supernodes() - Include supernodes required by this node + * @info: State information + * @depth: Current stack depth + * + * When we decided to include a node or property which is not at the top + * level, this function forces the inclusion of higher level nodes. For + * example, given this tree: + * + * / { + * testing { + * } + * } + * + * If we decide to include testing then we need the root node to have a valid + * tree. This function adds those regions. + */ +static int fdt_include_supernodes(struct fdt_region_state *info, int depth) +{ + int base = fdt_off_dt_struct(info->fdt); + int start, stop_at; + int i; + + /* + * Work down the stack looking for supernodes that we didn't include. + * The algortihm here is actually pretty simple, since we know that + * no previous subnode had to include these nodes, or if it did, we + * marked them as included (on the stack) already. + */ + for (i = 0; i <= depth; i++) { + if (!info->stack[i].included) { + start = info->stack[i].offset; + + /* Add the FDT_BEGIN_NODE tag of this supernode */ + fdt_next_tag(info->fdt, start, &stop_at); + if (fdt_add_region(info, base + start, stop_at - start)) + return -1; + + /* Remember that this supernode is now included */ + info->stack[i].included = 1; + info->can_merge = 1; + } + + /* Force (later) generation of the FDT_END_NODE tag */ + if (!info->stack[i].want) + info->stack[i].want = WANT_NODES_ONLY; + } + + return 0; +} + +enum { + FDT_DONE_NOTHING, + FDT_DONE_MEM_RSVMAP, + FDT_DONE_STRUCT, + FDT_DONE_END, + FDT_DONE_STRINGS, + FDT_DONE_ALL, +}; + +int fdt_first_region(const void *fdt, + int (*h_include)(void *priv, const void *fdt, int offset, + int type, const char *data, int size), + void *priv, struct fdt_region *region, + char *path, int path_len, int flags, + struct fdt_region_state *info) +{ + struct fdt_region_ptrs *p = &info->ptrs; + + /* Set up our state */ + info->fdt = fdt; + info->can_merge = 1; + info->max_regions = 1; + info->start = -1; + p->want = WANT_NOTHING; + p->end = path; + *p->end = '\0'; + p->nextoffset = 0; + p->depth = -1; + p->done = FDT_DONE_NOTHING; + + return fdt_next_region(fdt, h_include, priv, region, + path, path_len, flags, info); +} + +/*********************************************************************** + * + * Theory of operation + * + * Note: in this description 'included' means that a node (or other part + * of the tree) should be included in the region list, i.e. it will have + * a region which covers its part of the tree. + * + * This function maintains some state from the last time it is called. + * It checks the next part of the tree that it is supposed to look at + * (p.nextoffset) to see if that should be included or not. When it + * finds something to include, it sets info->start to its offset. This + * marks the start of the region we want to include. + * + * Once info->start is set to the start (i.e. not -1), we continue + * scanning until we find something that we don't want included. This + * will be the end of a region. At this point we can close off the + * region and add it to the list. So we do so, and reset info->start + * to -1. + * + * One complication here is that we want to merge regions. So when we + * come to add another region later, we may in fact merge it with the + * previous one if one ends where the other starts. + * + * The function fdt_add_region() will return -1 if it fails to add the + * region, because we already have a region ready to be returned, and + * the new one cannot be merged in with it. In this case, we must return + * the region we found, and wait for another call to this function. + * When it comes, we will repeat the processing of the tag and again + * try to add a region. This time it will succeed. + * + * The current state of the pointers (stack, offset, etc.) is maintained + * in a ptrs member. At the start of every loop iteration we make a copy + * of it. The copy is then updated as the tag is processed. Only if we + * get to the end of the loop iteration (and successfully call + * fdt_add_region() if we need to) can we commit the changes we have + * made to these pointers. For example, if we see an FDT_END_NODE tag, + * we will decrement the depth value. But if we need to add a region + * for this tag (let's say because the previous tag is included and this + * FDT_END_NODE tag is not included) then we will only commit the result + * if we were able to add the region. That allows us to retry again next + * time. + * + * We keep track of a variable called 'want' which tells us what we want + * to include when there is no specific information provided by the + * h_include function for a particular property. This basically handles + * the inclusion of properties which are pulled in by virtue of the node + * they are in. So if you include a node, its properties are also + * included. In this case 'want' will be WANT_NODES_AND_PROPS. The + * FDT_REG_DIRECT_SUBNODES feature also makes use of 'want'. While we + * are inside the subnode, 'want' will be set to WANT_NODES_ONLY, so + * that only the subnode's FDT_BEGIN_NODE and FDT_END_NODE tags will be + * included, and properties will be skipped. If WANT_NOTHING is + * selected, then we will just rely on what the h_include() function + * tells us. + * + * Using 'want' we work out 'include', which tells us whether this + * current tag should be included or not. As you can imagine, if the + * value of 'include' changes, that means we are on a boundary between + * nodes to include and nodes to exclude. At this point we either close + * off a previous region and add it to the list, or mark the start of a + * new region. + * + * Apart from the nodes, we have mem_rsvmap, the FDT_END tag and the + * string list. Each of these dealt with as a whole (i.e. we create a + * region for each if it is to be included). For mem_rsvmap we don't + * allow it to merge with the first struct region. For the stringlist, + * we don't allow it to merge with the last struct region (which + * contains at minimum the FDT_END tag). + * + *********************************************************************/ + +int fdt_next_region(const void *fdt, + int (*h_include)(void *priv, const void *fdt, int offset, + int type, const char *data, int size), + void *priv, struct fdt_region *region, + char *path, int path_len, int flags, + struct fdt_region_state *info) +{ + int base = fdt_off_dt_struct(fdt); + int last_node = 0; + const char *str; + + info->region = region; + info->count = 0; + if (info->ptrs.done < FDT_DONE_MEM_RSVMAP && + (flags & FDT_REG_ADD_MEM_RSVMAP)) { + /* Add the memory reserve map into its own region */ + if (fdt_add_region(info, fdt_off_mem_rsvmap(fdt), + fdt_off_dt_struct(fdt) - + fdt_off_mem_rsvmap(fdt))) + return 0; + info->can_merge = 0; /* Don't allow merging with this */ + info->ptrs.done = FDT_DONE_MEM_RSVMAP; + } + + /* + * Work through the tags one by one, deciding whether each needs to + * be included or not. We set the variable 'include' to indicate our + * decision. 'want' is used to track what we want to include - it + * allows us to pick up all the properties (and/or subnode tags) of + * a node. + */ + while (info->ptrs.done < FDT_DONE_STRUCT) { + const struct fdt_property *prop; + struct fdt_region_ptrs p; + const char *name; + int include = 0; + int stop_at = 0; + uint32_t tag; + int offset; + int val; + int len; + + /* + * Make a copy of our pointers. If we make it to the end of + * this block then we will commit them back to info->ptrs. + * Otherwise we can try again from the same starting state + * next time we are called. + */ + p = info->ptrs; + + /* + * Find the tag, and the offset of the next one. If we need to + * stop including tags, then by default we stop *after* + * including the current tag + */ + offset = p.nextoffset; + tag = fdt_next_tag(fdt, offset, &p.nextoffset); + stop_at = p.nextoffset; + + switch (tag) { + case FDT_PROP: + stop_at = offset; + prop = fdt_get_property_by_offset(fdt, offset, NULL); + str = fdt_string(fdt, fdt32_to_cpu(prop->nameoff)); + val = h_include(priv, fdt, last_node, FDT_IS_PROP, str, + strlen(str) + 1); + if (val == -1) { + include = p.want >= WANT_NODES_AND_PROPS; + } else { + include = val; + /* + * Make sure we include the } for this block. + * It might be more correct to have this done + * by the call to fdt_include_supernodes() in + * the case where it adds the node we are + * currently in, but this is equivalent. + */ + if ((flags & FDT_REG_SUPERNODES) && val && + !p.want) + p.want = WANT_NODES_ONLY; + } + + /* Value grepping is not yet supported */ + break; + + case FDT_NOP: + include = p.want >= WANT_NODES_AND_PROPS; + stop_at = offset; + break; + + case FDT_BEGIN_NODE: + last_node = offset; + p.depth++; + if (p.depth == FDT_MAX_DEPTH) + return -FDT_ERR_BADSTRUCTURE; + name = fdt_get_name(fdt, offset, &len); + if (p.end - path + 2 + len >= path_len) + return -FDT_ERR_NOSPACE; + + /* Build the full path of this node */ + if (p.end != path + 1) + *p.end++ = '/'; + strcpy(p.end, name); + p.end += len; + info->stack[p.depth].want = p.want; + info->stack[p.depth].offset = offset; + + /* + * If we are not intending to include this node unless + * it matches, make sure we stop *before* its tag. + */ + if (p.want == WANT_NODES_ONLY || + !(flags & (FDT_REG_DIRECT_SUBNODES | + FDT_REG_ALL_SUBNODES))) { + stop_at = offset; + p.want = WANT_NOTHING; + } + val = h_include(priv, fdt, offset, FDT_IS_NODE, path, + p.end - path + 1); + + /* Include this if requested */ + if (val) { + p.want = (flags & FDT_REG_ALL_SUBNODES) ? + WANT_ALL_NODES_AND_PROPS : + WANT_NODES_AND_PROPS; + } + + /* If not requested, decay our 'p.want' value */ + else if (p.want) { + if (p.want != WANT_ALL_NODES_AND_PROPS) + p.want--; + + /* Not including this tag, so stop now */ + } else { + stop_at = offset; + } + + /* + * Decide whether to include this tag, and update our + * stack with the state for this node + */ + include = p.want; + info->stack[p.depth].included = include; + break; + + case FDT_END_NODE: + include = p.want; + if (p.depth < 0) + return -FDT_ERR_BADSTRUCTURE; + + /* + * If we don't want this node, stop right away, unless + * we are including subnodes + */ + if (!p.want && !(flags & FDT_REG_DIRECT_SUBNODES)) + stop_at = offset; + p.want = info->stack[p.depth].want; + p.depth--; + while (p.end > path && *--p.end != '/') + ; + *p.end = '\0'; + break; + + case FDT_END: + /* We always include the end tag */ + include = 1; + p.done = FDT_DONE_STRUCT; + break; + } + + /* If this tag is to be included, mark it as region start */ + if (include && info->start == -1) { + /* Include any supernodes required by this one */ + if (flags & FDT_REG_SUPERNODES) { + if (fdt_include_supernodes(info, p.depth)) + return 0; + } + info->start = offset; + } + + /* + * If this tag is not to be included, finish up the current + * region. + */ + if (!include && info->start != -1) { + if (fdt_add_region(info, base + info->start, + stop_at - info->start)) + return 0; + info->start = -1; + info->can_merge = 1; + } + + /* If we have made it this far, we can commit our pointers */ + info->ptrs = p; + } + + /* Add a region for the END tag and a separate one for string table */ + if (info->ptrs.done < FDT_DONE_END) { + if (info->ptrs.nextoffset != fdt_size_dt_struct(fdt)) + return -FDT_ERR_BADSTRUCTURE; + + if (fdt_add_region(info, base + info->start, + info->ptrs.nextoffset - info->start)) + return 0; + info->ptrs.done++; + } + if (info->ptrs.done < FDT_DONE_STRINGS) { + if (flags & FDT_REG_ADD_STRING_TAB) { + info->can_merge = 0; + if (fdt_off_dt_strings(fdt) < + base + info->ptrs.nextoffset) + return -FDT_ERR_BADLAYOUT; + if (fdt_add_region(info, fdt_off_dt_strings(fdt), + fdt_size_dt_strings(fdt))) + return 0; + } + info->ptrs.done++; + } + + return info->count > 0 ? 0 : -FDT_ERR_NOTFOUND; +} diff --git a/common/image-fit-sig.c b/common/image-fit-sig.c index 490566ca90..3e73578594 100644 --- a/common/image-fit-sig.c +++ b/common/image-fit-sig.c @@ -11,6 +11,7 @@ #include <malloc.h> DECLARE_GLOBAL_DATA_PTR; #endif /* !USE_HOSTCC*/ +#include <fdt_region.h> #include <image.h> #include <u-boot/rsa.h> #include <u-boot/rsa-checksum.h> diff --git a/include/fdt_region.h b/include/fdt_region.h new file mode 100644 index 0000000000..ff7a1ccb9a --- /dev/null +++ b/include/fdt_region.h @@ -0,0 +1,304 @@ +/* SPDX-License-Identifier: GPL-2.0 */ + +#ifndef _FDT_REGION_H +#define _FDT_REGION_H + +#ifndef SWIG /* Not available in Python */ +struct fdt_region { + int offset; + int size; +}; + +/* + * Flags for fdt_find_regions() + * + * Add a region for the string table (always the last region) + */ +#define FDT_REG_ADD_STRING_TAB (1 << 0) + +/* + * Add all supernodes of a matching node/property, useful for creating a + * valid subset tree + */ +#define FDT_REG_SUPERNODES (1 << 1) + +/* Add the FDT_BEGIN_NODE tags of subnodes, including their names */ +#define FDT_REG_DIRECT_SUBNODES (1 << 2) + +/* Add all subnodes of a matching node */ +#define FDT_REG_ALL_SUBNODES (1 << 3) + +/* Add a region for the mem_rsvmap table (always the first region) */ +#define FDT_REG_ADD_MEM_RSVMAP (1 << 4) + +/* Indicates what an fdt part is (node, property, value) */ +#define FDT_IS_NODE (1 << 0) +#define FDT_IS_PROP (1 << 1) +#define FDT_IS_VALUE (1 << 2) /* not supported */ +#define FDT_IS_COMPAT (1 << 3) /* used internally */ +#define FDT_NODE_HAS_PROP (1 << 4) /* node contains prop */ + +#define FDT_ANY_GLOBAL (FDT_IS_NODE | FDT_IS_PROP | FDT_IS_VALUE | \ + FDT_IS_COMPAT) +#define FDT_IS_ANY 0x1f /* all the above */ + +/* We set a reasonable limit on the number of nested nodes */ +#define FDT_MAX_DEPTH 32 + +/* Decribes what we want to include from the current tag */ +enum want_t { + WANT_NOTHING, + WANT_NODES_ONLY, /* No properties */ + WANT_NODES_AND_PROPS, /* Everything for one level */ + WANT_ALL_NODES_AND_PROPS /* Everything for all levels */ +}; + +/* Keeps track of the state at parent nodes */ +struct fdt_subnode_stack { + int offset; /* Offset of node */ + enum want_t want; /* The 'want' value here */ + int included; /* 1 if we included this node, 0 if not */ +}; + +struct fdt_region_ptrs { + int depth; /* Current tree depth */ + int done; /* What we have completed scanning */ + enum want_t want; /* What we are currently including */ + char *end; /* Pointer to end of full node path */ + int nextoffset; /* Next node offset to check */ +}; + +/* The state of our finding algortihm */ +struct fdt_region_state { + struct fdt_subnode_stack stack[FDT_MAX_DEPTH]; /* node stack */ + struct fdt_region *region; /* Contains list of regions found */ + int count; /* Numnber of regions found */ + const void *fdt; /* FDT blob */ + int max_regions; /* Maximum regions to find */ + int can_merge; /* 1 if we can merge with previous region */ + int start; /* Start position of current region */ + struct fdt_region_ptrs ptrs; /* Pointers for what we are up to */ +}; + +/** + * fdt_find_regions() - find regions in device tree + * + * Given a list of nodes to include and properties to exclude, find + * the regions of the device tree which describe those included parts. + * + * The intent is to get a list of regions which will be invariant provided + * those parts are invariant. For example, if you request a list of regions + * for all nodes but exclude the property "data", then you will get the + * same region contents regardless of any change to "data" properties. + * + * This function can be used to produce a byte-stream to send to a hashing + * function to verify that critical parts of the FDT have not changed. + * + * Nodes which are given in 'inc' are included in the region list, as + * are the names of the immediate subnodes nodes (but not the properties + * or subnodes of those subnodes). + * + * For eaxample "/" means to include the root node, all root properties + * and the FDT_BEGIN_NODE and FDT_END_NODE of all subnodes of /. The latter + * ensures that we capture the names of the subnodes. In a hashing situation + * it prevents the root node from changing at all Any change to non-excluded + * properties, names of subnodes or number of subnodes would be detected. + * + * When used with FITs this provides the ability to hash and sign parts of + * the FIT based on different configurations in the FIT. Then it is + * impossible to change anything about that configuration (include images + * attached to the configuration), but it may be possible to add new + * configurations, new images or new signatures within the existing + * framework. + * + * Adding new properties to a device tree may result in the string table + * being extended (if the new property names are different from those + * already added). This function can optionally include a region for + * the string table so that this can be part of the hash too. + * + * The device tree header is not included in the list. + * + * @fdt: Device tree to check + * @inc: List of node paths to included + * @inc_count: Number of node paths in list + * @exc_prop: List of properties names to exclude + * @exc_prop_count: Number of properties in exclude list + * @region: Returns list of regions + * @max_region: Maximum length of region list + * @path: Pointer to a temporary string for the function to use for + * building path names + * @path_len: Length of path, must be large enough to hold the longest + * path in the tree + * @add_string_tab: 1 to add a region for the string table + * @return number of regions in list. If this is >max_regions then the + * region array was exhausted. You should increase max_regions and try + * the call again. + */ +int fdt_find_regions(const void *fdt, char * const inc[], int inc_count, + char * const exc_prop[], int exc_prop_count, + struct fdt_region region[], int max_regions, + char *path, int path_len, int add_string_tab); + +/** + * fdt_first_region() - find regions in device tree + * + * Given a nodes and properties to include and properties to exclude, find + * the regions of the device tree which describe those included parts. + * + * The use for this function is twofold. Firstly it provides a convenient + * way of performing a structure-aware grep of the tree. For example it is + * possible to grep for a node and get all the properties associated with + * that node. Trees can be subsetted easily, by specifying the nodes that + * are required, and then writing out the regions returned by this function. + * This is useful for small resource-constrained systems, such as boot + * loaders, which want to use an FDT but do not need to know about all of + * it. + * + * Secondly it makes it easy to hash parts of the tree and detect changes. + * The intent is to get a list of regions which will be invariant provided + * those parts are invariant. For example, if you request a list of regions + * for all nodes but exclude the property "data", then you will get the + * same region contents regardless of any change to "data" properties. + * + * This function can be used to produce a byte-stream to send to a hashing + * function to verify that critical parts of the FDT have not changed. + * Note that semantically null changes in order could still cause false + * hash misses. Such reordering might happen if the tree is regenerated + * from source, and nodes are reordered (the bytes-stream will be emitted + * in a different order and many hash functions will detect this). However + * if an existing tree is modified using libfdt functions, such as + * fdt_add_subnode() and fdt_setprop(), then this problem is avoided. + * + * The nodes/properties to include/exclude are defined by a function + * provided by the caller. This function is called for each node and + * property, and must return: + * + * 0 - to exclude this part + * 1 - to include this part + * -1 - for FDT_IS_PROP only: no information is available, so include + * if its containing node is included + * + * The last case is only used to deal with properties. Often a property is + * included if its containing node is included - this is the case where + * -1 is returned.. However if the property is specifically required to be + * included/excluded, then 0 or 1 can be returned. Note that including a + * property when the FDT_REG_SUPERNODES flag is given will force its + * containing node to be included since it is not valid to have a property + * that is not in a node. + * + * Using the information provided, the inclusion of a node can be controlled + * either by a node name or its compatible string, or any other property + * that the function can determine. + * + * As an example, including node "/" means to include the root node and all + * root properties. A flag provides a way of also including supernodes (of + * which there is none for the root node), and another flag includes + * immediate subnodes, so in this case we would get the FDT_BEGIN_NODE and + * FDT_END_NODE of all subnodes of /. + * + * The subnode feature helps in a hashing situation since it prevents the + * root node from changing at all. Any change to non-excluded properties, + * names of subnodes or number of subnodes would be detected. + * + * When used with FITs this provides the ability to hash and sign parts of + * the FIT based on different configurations in the FIT. Then it is + * impossible to change anything about that configuration (include images + * attached to the configuration), but it may be possible to add new + * configurations, new images or new signatures within the existing + * framework. + * + * Adding new properties to a device tree may result in the string table + * being extended (if the new property names are different from those + * already added). This function can optionally include a region for + * the string table so that this can be part of the hash too. This is always + * the last region. + * + * The FDT also has a mem_rsvmap table which can also be included, and is + * always the first region if so. + * + * The device tree header is not included in the region list. Since the + * contents of the FDT are changing (shrinking, often), the caller will need + * to regenerate the header anyway. + * + * @fdt: Device tree to check + * @h_include: Function to call to determine whether to include a part or + * not: + * + * @priv: Private pointer as passed to fdt_find_regions() + * @fdt: Pointer to FDT blob + * @offset: Offset of this node / property + * @type: Type of this part, FDT_IS_... + * @data: Pointer to data (node name, property name, compatible + * string, value (not yet supported) + * @size: Size of data, or 0 if none + * @return 0 to exclude, 1 to include, -1 if no information is + * available + * @priv: Private pointer passed to h_include + * @region: Returns list of regions, sorted by offset + * @max_regions: Maximum length of region list + * @path: Pointer to a temporary string for the function to use for + * building path names + * @path_len: Length of path, must be large enough to hold the longest + * path in the tree + * @flags: Various flags that control the region algortihm, see + * FDT_REG_... + * @return number of regions in list. If this is >max_regions then the + * region array was exhausted. You should increase max_regions and try + * the call again. Only the first max_regions elements are available in the + * array. + * + * On error a -ve value is return, which can be: + * + * -FDT_ERR_BADSTRUCTURE (too deep or more END tags than BEGIN tags + * -FDT_ERR_BADLAYOUT + * -FDT_ERR_NOSPACE (path area is too small) + */ +int fdt_first_region(const void *fdt, + int (*h_include)(void *priv, const void *fdt, int offset, + int type, const char *data, int size), + void *priv, struct fdt_region *region, + char *path, int path_len, int flags, + struct fdt_region_state *info); + +/** fdt_next_region() - find next region + * + * See fdt_first_region() for full description. This function finds the + * next region according to the provided parameters, which must be the same + * as passed to fdt_first_region(). + * + * This function can additionally return -FDT_ERR_NOTFOUND when there are no + * more regions + */ +int fdt_next_region(const void *fdt, + int (*h_include)(void *priv, const void *fdt, int offset, + int type, const char *data, int size), + void *priv, struct fdt_region *region, + char *path, int path_len, int flags, + struct fdt_region_state *info); + +/** + * fdt_add_alias_regions() - find aliases that point to existing regions + * + * Once a device tree grep is complete some of the nodes will be present + * and some will have been dropped. This function checks all the alias nodes + * to figure out which points point to nodes which are still present. These + * aliases need to be kept, along with the nodes they reference. + * + * Given a list of regions function finds the aliases that still apply and + * adds more regions to the list for these. This function is called after + * fdt_next_region() has finished returning regions and requires the same + * state. + * + * @fdt: Device tree file to reference + * @region: List of regions that will be kept + * @count: Number of regions + * @max_regions: Number of entries that can fit in @region + * @info: Region state as returned from fdt_next_region() + * @return new number of regions in @region (i.e. count + the number added) + * or -FDT_ERR_NOSPACE if there was not enough space. + */ +int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count, + int max_regions, struct fdt_region_state *info); +#endif /* SWIG */ + +#endif /* _FDT_REGION_H */ diff --git a/include/linux/libfdt.h b/include/linux/libfdt.h index eeb2344971..39dbc88aa5 100644 --- a/include/linux/libfdt.h +++ b/include/linux/libfdt.h @@ -8,305 +8,6 @@ #include "../../scripts/dtc/libfdt/libfdt.h" /* U-Boot local hacks */ - -#ifndef SWIG /* Not available in Python */ -struct fdt_region { - int offset; - int size; -}; - -/* - * Flags for fdt_find_regions() - * - * Add a region for the string table (always the last region) - */ -#define FDT_REG_ADD_STRING_TAB (1 << 0) - -/* - * Add all supernodes of a matching node/property, useful for creating a - * valid subset tree - */ -#define FDT_REG_SUPERNODES (1 << 1) - -/* Add the FDT_BEGIN_NODE tags of subnodes, including their names */ -#define FDT_REG_DIRECT_SUBNODES (1 << 2) - -/* Add all subnodes of a matching node */ -#define FDT_REG_ALL_SUBNODES (1 << 3) - -/* Add a region for the mem_rsvmap table (always the first region) */ -#define FDT_REG_ADD_MEM_RSVMAP (1 << 4) - -/* Indicates what an fdt part is (node, property, value) */ -#define FDT_IS_NODE (1 << 0) -#define FDT_IS_PROP (1 << 1) -#define FDT_IS_VALUE (1 << 2) /* not supported */ -#define FDT_IS_COMPAT (1 << 3) /* used internally */ -#define FDT_NODE_HAS_PROP (1 << 4) /* node contains prop */ - -#define FDT_ANY_GLOBAL (FDT_IS_NODE | FDT_IS_PROP | FDT_IS_VALUE | \ - FDT_IS_COMPAT) -#define FDT_IS_ANY 0x1f /* all the above */ - -/* We set a reasonable limit on the number of nested nodes */ -#define FDT_MAX_DEPTH 32 - -/* Decribes what we want to include from the current tag */ -enum want_t { - WANT_NOTHING, - WANT_NODES_ONLY, /* No properties */ - WANT_NODES_AND_PROPS, /* Everything for one level */ - WANT_ALL_NODES_AND_PROPS /* Everything for all levels */ -}; - -/* Keeps track of the state at parent nodes */ -struct fdt_subnode_stack { - int offset; /* Offset of node */ - enum want_t want; /* The 'want' value here */ - int included; /* 1 if we included this node, 0 if not */ -}; - -struct fdt_region_ptrs { - int depth; /* Current tree depth */ - int done; /* What we have completed scanning */ - enum want_t want; /* What we are currently including */ - char *end; /* Pointer to end of full node path */ - int nextoffset; /* Next node offset to check */ -}; - -/* The state of our finding algortihm */ -struct fdt_region_state { - struct fdt_subnode_stack stack[FDT_MAX_DEPTH]; /* node stack */ - struct fdt_region *region; /* Contains list of regions found */ - int count; /* Numnber of regions found */ - const void *fdt; /* FDT blob */ - int max_regions; /* Maximum regions to find */ - int can_merge; /* 1 if we can merge with previous region */ - int start; /* Start position of current region */ - struct fdt_region_ptrs ptrs; /* Pointers for what we are up to */ -}; - -/** - * fdt_find_regions() - find regions in device tree - * - * Given a list of nodes to include and properties to exclude, find - * the regions of the device tree which describe those included parts. - * - * The intent is to get a list of regions which will be invariant provided - * those parts are invariant. For example, if you request a list of regions - * for all nodes but exclude the property "data", then you will get the - * same region contents regardless of any change to "data" properties. - * - * This function can be used to produce a byte-stream to send to a hashing - * function to verify that critical parts of the FDT have not changed. - * - * Nodes which are given in 'inc' are included in the region list, as - * are the names of the immediate subnodes nodes (but not the properties - * or subnodes of those subnodes). - * - * For eaxample "/" means to include the root node, all root properties - * and the FDT_BEGIN_NODE and FDT_END_NODE of all subnodes of /. The latter - * ensures that we capture the names of the subnodes. In a hashing situation - * it prevents the root node from changing at all Any change to non-excluded - * properties, names of subnodes or number of subnodes would be detected. - * - * When used with FITs this provides the ability to hash and sign parts of - * the FIT based on different configurations in the FIT. Then it is - * impossible to change anything about that configuration (include images - * attached to the configuration), but it may be possible to add new - * configurations, new images or new signatures within the existing - * framework. - * - * Adding new properties to a device tree may result in the string table - * being extended (if the new property names are different from those - * already added). This function can optionally include a region for - * the string table so that this can be part of the hash too. - * - * The device tree header is not included in the list. - * - * @fdt: Device tree to check - * @inc: List of node paths to included - * @inc_count: Number of node paths in list - * @exc_prop: List of properties names to exclude - * @exc_prop_count: Number of properties in exclude list - * @region: Returns list of regions - * @max_region: Maximum length of region list - * @path: Pointer to a temporary string for the function to use for - * building path names - * @path_len: Length of path, must be large enough to hold the longest - * path in the tree - * @add_string_tab: 1 to add a region for the string table - * @return number of regions in list. If this is >max_regions then the - * region array was exhausted. You should increase max_regions and try - * the call again. - */ -int fdt_find_regions(const void *fdt, char * const inc[], int inc_count, - char * const exc_prop[], int exc_prop_count, - struct fdt_region region[], int max_regions, - char *path, int path_len, int add_string_tab); - -/** - * fdt_first_region() - find regions in device tree - * - * Given a nodes and properties to include and properties to exclude, find - * the regions of the device tree which describe those included parts. - * - * The use for this function is twofold. Firstly it provides a convenient - * way of performing a structure-aware grep of the tree. For example it is - * possible to grep for a node and get all the properties associated with - * that node. Trees can be subsetted easily, by specifying the nodes that - * are required, and then writing out the regions returned by this function. - * This is useful for small resource-constrained systems, such as boot - * loaders, which want to use an FDT but do not need to know about all of - * it. - * - * Secondly it makes it easy to hash parts of the tree and detect changes. - * The intent is to get a list of regions which will be invariant provided - * those parts are invariant. For example, if you request a list of regions - * for all nodes but exclude the property "data", then you will get the - * same region contents regardless of any change to "data" properties. - * - * This function can be used to produce a byte-stream to send to a hashing - * function to verify that critical parts of the FDT have not changed. - * Note that semantically null changes in order could still cause false - * hash misses. Such reordering might happen if the tree is regenerated - * from source, and nodes are reordered (the bytes-stream will be emitted - * in a different order and many hash functions will detect this). However - * if an existing tree is modified using libfdt functions, such as - * fdt_add_subnode() and fdt_setprop(), then this problem is avoided. - * - * The nodes/properties to include/exclude are defined by a function - * provided by the caller. This function is called for each node and - * property, and must return: - * - * 0 - to exclude this part - * 1 - to include this part - * -1 - for FDT_IS_PROP only: no information is available, so include - * if its containing node is included - * - * The last case is only used to deal with properties. Often a property is - * included if its containing node is included - this is the case where - * -1 is returned.. However if the property is specifically required to be - * included/excluded, then 0 or 1 can be returned. Note that including a - * property when the FDT_REG_SUPERNODES flag is given will force its - * containing node to be included since it is not valid to have a property - * that is not in a node. - * - * Using the information provided, the inclusion of a node can be controlled - * either by a node name or its compatible string, or any other property - * that the function can determine. - * - * As an example, including node "/" means to include the root node and all - * root properties. A flag provides a way of also including supernodes (of - * which there is none for the root node), and another flag includes - * immediate subnodes, so in this case we would get the FDT_BEGIN_NODE and - * FDT_END_NODE of all subnodes of /. - * - * The subnode feature helps in a hashing situation since it prevents the - * root node from changing at all. Any change to non-excluded properties, - * names of subnodes or number of subnodes would be detected. - * - * When used with FITs this provides the ability to hash and sign parts of - * the FIT based on different configurations in the FIT. Then it is - * impossible to change anything about that configuration (include images - * attached to the configuration), but it may be possible to add new - * configurations, new images or new signatures within the existing - * framework. - * - * Adding new properties to a device tree may result in the string table - * being extended (if the new property names are different from those - * already added). This function can optionally include a region for - * the string table so that this can be part of the hash too. This is always - * the last region. - * - * The FDT also has a mem_rsvmap table which can also be included, and is - * always the first region if so. - * - * The device tree header is not included in the region list. Since the - * contents of the FDT are changing (shrinking, often), the caller will need - * to regenerate the header anyway. - * - * @fdt: Device tree to check - * @h_include: Function to call to determine whether to include a part or - * not: - * - * @priv: Private pointer as passed to fdt_find_regions() - * @fdt: Pointer to FDT blob - * @offset: Offset of this node / property - * @type: Type of this part, FDT_IS_... - * @data: Pointer to data (node name, property name, compatible - * string, value (not yet supported) - * @size: Size of data, or 0 if none - * @return 0 to exclude, 1 to include, -1 if no information is - * available - * @priv: Private pointer passed to h_include - * @region: Returns list of regions, sorted by offset - * @max_regions: Maximum length of region list - * @path: Pointer to a temporary string for the function to use for - * building path names - * @path_len: Length of path, must be large enough to hold the longest - * path in the tree - * @flags: Various flags that control the region algortihm, see - * FDT_REG_... - * @return number of regions in list. If this is >max_regions then the - * region array was exhausted. You should increase max_regions and try - * the call again. Only the first max_regions elements are available in the - * array. - * - * On error a -ve value is return, which can be: - * - * -FDT_ERR_BADSTRUCTURE (too deep or more END tags than BEGIN tags - * -FDT_ERR_BADLAYOUT - * -FDT_ERR_NOSPACE (path area is too small) - */ -int fdt_first_region(const void *fdt, - int (*h_include)(void *priv, const void *fdt, int offset, - int type, const char *data, int size), - void *priv, struct fdt_region *region, - char *path, int path_len, int flags, - struct fdt_region_state *info); - -/** fdt_next_region() - find next region - * - * See fdt_first_region() for full description. This function finds the - * next region according to the provided parameters, which must be the same - * as passed to fdt_first_region(). - * - * This function can additionally return -FDT_ERR_NOTFOUND when there are no - * more regions - */ -int fdt_next_region(const void *fdt, - int (*h_include)(void *priv, const void *fdt, int offset, - int type, const char *data, int size), - void *priv, struct fdt_region *region, - char *path, int path_len, int flags, - struct fdt_region_state *info); - -/** - * fdt_add_alias_regions() - find aliases that point to existing regions - * - * Once a device tree grep is complete some of the nodes will be present - * and some will have been dropped. This function checks all the alias nodes - * to figure out which points point to nodes which are still present. These - * aliases need to be kept, along with the nodes they reference. - * - * Given a list of regions function finds the aliases that still apply and - * adds more regions to the list for these. This function is called after - * fdt_next_region() has finished returning regions and requires the same - * state. - * - * @fdt: Device tree file to reference - * @region: List of regions that will be kept - * @count: Number of regions - * @max_regions: Number of entries that can fit in @region - * @info: Region state as returned from fdt_next_region() - * @return new number of regions in @region (i.e. count + the number added) - * or -FDT_ERR_NOSPACE if there was not enough space. - */ -int fdt_add_alias_regions(const void *fdt, struct fdt_region *region, int count, - int max_regions, struct fdt_region_state *info); -#endif /* SWIG */ - extern struct fdt_header *working_fdt; /* Pointer to the working fdt */ #endif /* _INCLUDE_LIBFDT_H_ */ diff --git a/tools/fdtgrep.c b/tools/fdtgrep.c index 2a8058f57f..7e168a1e6b 100644 --- a/tools/fdtgrep.c +++ b/tools/fdtgrep.c @@ -17,6 +17,7 @@ #include <stdlib.h> #include <string.h> #include <unistd.h> +#include <fdt_region.h> #include "fdt_host.h" #include "libfdt_internal.h" diff --git a/tools/image-host.c b/tools/image-host.c index 5bb68965e7..9a83b7f675 100644 --- a/tools/image-host.c +++ b/tools/image-host.c @@ -10,6 +10,7 @@ #include "mkimage.h" #include <bootm.h> +#include <fdt_region.h> #include <image.h> #include <version.h> |