diff options
Diffstat (limited to 'cddl/contrib/opensolaris/lib/libctf')
| -rw-r--r-- | cddl/contrib/opensolaris/lib/libctf/common/ctf.5 | 1224 | ||||
| -rw-r--r-- | cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c | 528 | ||||
| -rw-r--r-- | cddl/contrib/opensolaris/lib/libctf/common/ctf_subr.c | 83 | ||||
| -rw-r--r-- | cddl/contrib/opensolaris/lib/libctf/common/libctf.h | 60 |
4 files changed, 1895 insertions, 0 deletions
diff --git a/cddl/contrib/opensolaris/lib/libctf/common/ctf.5 b/cddl/contrib/opensolaris/lib/libctf/common/ctf.5 new file mode 100644 index 000000000000..d9f41de6a9ca --- /dev/null +++ b/cddl/contrib/opensolaris/lib/libctf/common/ctf.5 @@ -0,0 +1,1224 @@ +.\" +.\" This file and its contents are supplied under the terms of the +.\" Common Development and Distribution License ("CDDL"), version 1.0. +.\" You may only use this file in accordance with the terms of version +.\" 1.0 of the CDDL. +.\" +.\" A full copy of the text of the CDDL should have accompanied this +.\" source. A copy of the CDDL is also available via the Internet at +.\" http://www.illumos.org/license/CDDL. +.\" +.\" +.\" Copyright (c) 2014 Joyent, Inc. +.\" +.Dd Sep 26, 2014 +.Dt CTF 5 +.Os +.Sh NAME +.Nm ctf +.Nd Compact C Type Format +.Sh SYNOPSIS +.In sys/ctf.h +.Sh DESCRIPTION +.Nm +is designed to be a compact representation of the C programming +language's type information focused on serving the needs of dynamic +tracing, debuggers, and other in-situ and post-mortem introspection +tools. +.Nm +data is generally included in +.Sy ELF +objects and is tagged as +.Sy SHT_PROGBITS +to ensure that the data is accessible in a running process and in subsequent +core dumps, if generated. +.Lp +The +.Nm +data contained in each file has information about the layout and +sizes of C types, including intrinsic types, enumerations, structures, +typedefs, and unions, that are used by the corresponding +.Sy ELF +object. +The +.Nm +data may also include information about the types of global objects and +the return type and arguments of functions in the symbol table. +.Lp +Because a +.Nm +file is often embedded inside a file, rather than being a standalone +file itself, it may also be referred to as a +.Nm +.Sy container . +.Lp +On +.Fx +systems, +.Nm +data is consumed by +.Xr dtrace 1 . +Programmatic access to +.Nm +data can be obtained through libctf. +.Lp +The +.Nm +file format is broken down into seven different sections. +The first section is the +.Sy preamble +and +.Sy header , +which describes the version of the +.Nm +file, the links it has to other +.Nm +files, and the sizes of the other sections. +The next section is the +.Sy label +section, +which provides a way of identifying similar groups of +.Nm +data across multiple files. +This is followed by the +.Sy object +information section, which describes the types of global +symbols. +The subsequent section is the +.Sy function +information section, which describes the return +types and arguments of functions. +The next section is the +.Sy type +information section, which describes +the format and layout of the C types themselves, and finally the last +section is the +.Sy string +section, which contains the names of types, enumerations, members, and +labels. +.Lp +While strictly speaking, only the +.Sy preamble +and +.Sy header +are required, to be actually useful, both the type and string +sections are necessary. +.Lp +A +.Nm +file may contain all of the type information that it requires, or it +may optionally refer to another +.Nm +file which holds the remaining types. +When a +.Nm +file refers to another file, it is called the +.Sy child +and the file it refers to is called the +.Sy parent . +A given file may only refer to one parent. +This process is called +.Em uniquification +because it ensures each child only has type information that is +unique to it. +A common example of this is that most kernel modules in illumos are uniquified +against the kernel module +.Sy genunix +and the type information that comes from the +.Sy IP +module. +This means that a module only has types that are unique to itself and the most +common types in the kernel are not duplicated. +.Sh FILE FORMAT +This documents version +.Em two +of the +.Nm +file format. +All applications and tools on +.Fx +currently produce and operate on this version. +.Lp +The file format can be summarized with the following image, the +following sections will cover this in more detail. +.Bd -literal + + +-------------+ 0t0 ++--------| Preamble | +| +-------------+ 0t4 +|+-------| Header | +|| +-------------+ 0t36 + cth_lbloff +||+------| Labels | +||| +-------------+ 0t36 + cth_objtoff +|||+-----| Objects | +|||| +-------------+ 0t36 + cth_funcoff +||||+----| Functions | +||||| +-------------+ 0t36 + cth_typeoff +|||||+---| Types | +|||||| +-------------+ 0t36 + cth_stroff +||||||+--| Strings | +||||||| +-------------+ 0t36 + cth_stroff + cth_strlen +||||||| +||||||| +||||||| +||||||| +-- magic - vers flags +||||||| | | | | +||||||| +------+------+------+------+ ++---------| 0xcf | 0xf1 | 0x02 | 0x00 | + |||||| +------+------+------+------+ + |||||| 0 1 2 3 4 + |||||| + |||||| + parent label + objects + |||||| | + parent name | + functions + strings + |||||| | | + label | | + types | + strlen + |||||| | | | | | | | | + |||||| +------+------+------+------+------+-------+-------+-------+ + +--------| 0x00 | 0x00 | 0x00 | 0x08 | 0x36 | 0x110 | 0x5f4 | 0x611 | + ||||| +------+------+------+------+------+-------+-------+-------+ + ||||| 0x04 0x08 0x0c 0x10 0x14 0x18 0x1c 0x20 0x24 + ||||| + ||||| + Label name + ||||| | + Label type + ||||| | | + Next label + ||||| | | | + ||||| +-------+------+-----+ + +-----------| 0x01 | 0x42 | ... | + |||| +-------+------+-----+ + |||| cth_lbloff +0x4 +0x8 cth_objtoff + |||| + |||| + |||| Symidx 0t15 0t43 0t44 + |||| +------+------+------+-----+ + +----------| 0x00 | 0x42 | 0x36 | ... | + ||| +------+------+------+-----+ + ||| cth_objtoff +0x2 +0x4 +0x6 cth_funcoff + ||| + ||| + CTF_TYPE_INFO + CTF_TYPE_INFO + ||| | + Return type | + ||| | | + arg0 | + ||| +--------+------+------+-----+ + +---------| 0x2c10 | 0x08 | 0x0c | ... | + || +--------+------+------+-----+ + || cth_funcff +0x2 +0x4 +0x6 cth_typeoff + || + || + ctf_stype_t for type 1 + || | integer + integer encoding + || | | + ctf_stype_t for type 2 + || | | | + || +--------------------+-----------+-----+ + +--------| 0x19 * 0xc01 * 0x0 | 0x1000000 | ... | + | +--------------------+-----------+-----+ + | cth_typeoff +0x08 +0x0c cth_stroff + | + | +--- str 0 + | | +--- str 1 + str 2 + | | | | + | v v v + | +----+---+---+---+----+---+---+---+---+---+----+ + +---| \\0 | i | n | t | \\0 | f | o | o | _ | t | \\0 | + +----+---+---+---+----+---+---+---+---+---+----+ + 0 1 2 3 4 5 6 7 8 9 10 11 +.Ed +.Lp +Every +.Nm +file begins with a +.Sy preamble , +followed by a +.Sy header . +The +.Sy preamble +is defined as follows: +.Bd -literal +typedef struct ctf_preamble { + uint16_t ctp_magic; /* magic number (CTF_MAGIC) */ + uint8_t ctp_version; /* data format version number (CTF_VERSION) */ + uint8_t ctp_flags; /* flags (see below) */ +} ctf_preamble_t; +.Ed +.Pp +The +.Sy preamble +is four bytes long and must be four byte aligned. +This +.Sy preamble +defines the version of the +.Nm +file which defines the format of the rest of the header. +While the header may change in subsequent versions, the preamble will not change +across versions, though the interpretation of its flags may change from +version to version. +The +.Em ctp_magic +member defines the magic number for the +.Nm +file format. +This must always be +.Li 0xcff1 . +If another value is encountered, then the file should not be treated as +a +.Nm +file. +The +.Em ctp_version +member defines the version of the +.Nm +file. +The current version is +.Li 2 . +It is possible to encounter an unsupported version. +In that case, software should not try to parse the format, as it may have +changed. +Finally, the +.Em ctp_flags +member describes aspects of the file which modify its interpretation. +The following flags are currently defined: +.Bd -literal +#define CTF_F_COMPRESS 0x01 +.Ed +.Pp +The flag +.Sy CTF_F_COMPRESS +indicates that the body of the +.Nm +file, all the data following the +.Sy header , +has been compressed through the +.Sy zlib +library and its +.Sy deflate +algorithm. +If this flag is not present, then the body has not been compressed and no +special action is needed to interpret it. +All offsets into the data as described by +.Sy header , +always refer to the +.Sy uncompressed +data. +.Lp +In version two of the +.Nm +file format, the +.Sy header +denotes whether or not this +.Nm +file is the child of another +.Nm +file and also indicates the size of the remaining sections. +The structure for the +.Sy header +logically contains a copy of the +.Sy preamble +and the two have a combined size of 36 bytes. +.Bd -literal +typedef struct ctf_header { + ctf_preamble_t cth_preamble; + uint32_t cth_parlabel; /* ref to name of parent lbl uniq'd against */ + uint32_t cth_parname; /* ref to basename of parent */ + uint32_t cth_lbloff; /* offset of label section */ + uint32_t cth_objtoff; /* offset of object section */ + uint32_t cth_funcoff; /* offset of function section */ + uint32_t cth_typeoff; /* offset of type section */ + uint32_t cth_stroff; /* offset of string section */ + uint32_t cth_strlen; /* length of string section in bytes */ +} ctf_header_t; +.Ed +.Pp +After the +.Sy preamble , +the next two members +.Em cth_parlablel +and +.Em cth_parname , +are used to identify the parent. +The value of both members are offsets into the +.Sy string +section which point to the start of a null-terminated string. +For more information on the encoding of strings, see the subsection on +.Sx String Identifiers . +If the value of either is zero, then there is no entry for that +member. +If the member +.Em cth_parlabel +is set, then the +.Em ctf_parname +member must be set, otherwise it will not be possible to find the +parent. +If +.Em ctf_parname +is set, it is not necessary to define +.Em cth_parlabel , +as the parent may not have a label. +For more information on labels and their interpretation, see +.Sx The Label Section . +.Lp +The remaining members (excepting +.Em cth_strlen ) +describe the beginning of the corresponding sections. +These offsets are relative to the end of the +.Sy header . +Therefore, something with an offset of 0 is at an offset of thirty-six +bytes relative to the start of the +.Nm +file. +The difference between members indicates the size of the section itself. +Different offsets have different alignment requirements. +The start of the +.Em cth_objotoff +and +.Em cth_funcoff +must be two byte aligned, while the sections +.Em cth_lbloff +and +.Em cth_typeoff +must be four-byte aligned. +The section +.Em cth_stroff +has no alignment requirements. +To calculate the size of a given section, excepting the +.Sy string +section, one should subtract the offset of the section from the following one. +For example, the size of the +.Sy types +section can be calculated by subtracting +.Em cth_stroff +from +.Em cth_typeoff . +.Lp +Finally, the member +.Em cth_strlen +describes the length of the string section itself. +From it, you can also calculate the size of the entire +.Nm +file by adding together the size of the +.Sy ctf_header_t , +the offset of the string section in +.Em cth_stroff , +and the size of the string section in +.Em cth_srlen . +.Ss Type Identifiers +Through the +.Nm ctf +data, types are referred to by identifiers. +A given +.Nm +file supports up to 32767 (0x7fff) types. +The first valid type identifier is 0x1. +When a given +.Nm +file is a child, indicated by a non-zero entry for the +.Sy header Ns 's +.Em cth_parname , +then the first valid type identifier is 0x8000 and the last is 0xffff. +In this case, type identifiers 0x1 through 0x7fff are references to the +parent. +.Lp +The type identifier zero is a sentinel value used to indicate that there +is no type information available or it is an unknown type. +.Lp +Throughout the file format, the identifier is stored in different sized +values; however, the minimum size to represent a given identifier is a +.Sy uint16_t . +Other consumers of +.Nm +information may use larger or opaque identifiers. +.Ss String Identifiers +String identifiers are always encoded as four byte unsigned integers +which are an offset into a string table. +The +.Nm +format supports two different string tables which have an identifier of +zero or one. +This identifier is stored in the high-order bit of the unsigned four byte +offset. +Therefore, the maximum supported offset into one of these tables is 0x7ffffffff. +.Lp +Table identifier zero, always refers to the +.Sy string +section in the CTF file itself. +String table identifier one refers to an external string table which is the ELF +string table for the ELF symbol table associated with the +.Nm +container. +.Ss Type Encoding +Every +.Nm +type begins with metadata encoded into a +.Sy uint16_t . +This encoded information tells us three different pieces of information: +.Bl -bullet -offset indent -compact +.It +The kind of the type +.It +Whether this type is a root type or not +.It +The length of the variable data +.El +.Lp +The 16 bits that make up the encoding are broken down such that you have +five bits for the kind, one bit for indicating whether or not it is a +root type, and 10 bits for the variable length. +This is laid out as follows: +.Bd -literal -offset indent ++--------------------+ +| kind | root | vlen | ++--------------------+ +15 11 10 9 0 +.Ed +.Lp +The current version of the file format defines 14 different kinds. +The interpretation of these different kinds will be discussed in the section +.Sx The Type Section . +If a kind is encountered that is not listed below, then it is not a valid +.Nm +file. +The kinds are defined as follows: +.Bd -literal -offset indent +#define CTF_K_UNKNOWN 0 +#define CTF_K_INTEGER 1 +#define CTF_K_FLOAT 2 +#define CTF_K_POINTER 3 +#define CTF_K_ARRAY 4 +#define CTF_K_FUNCTION 5 +#define CTF_K_STRUCT 6 +#define CTF_K_UNION 7 +#define CTF_K_ENUM 8 +#define CTF_K_FORWARD 9 +#define CTF_K_TYPEDEF 10 +#define CTF_K_VOLATILE 11 +#define CTF_K_CONST 12 +#define CTF_K_RESTRICT 13 +.Ed +.Lp +Programs directly reference many types; however, other types are referenced +indirectly because they are part of some other structure. +These types that are referenced directly and used are called +.Sy root +types. +Other types may be used indirectly, for example, a program may reference +a structure directly, but not one of its members which has a type. +That type is not considered a +.Sy root +type. +If a type is a +.Sy root +type, then it will have bit 10 set. +.Lp +The variable length section is specific to each kind and is discussed in the +section +.Sx The Type Section . +.Lp +The following macros are useful for constructing and deconstructing the encoded +type information: +.Bd -literal -offset indent + +#define CTF_MAX_VLEN 0x3ff +#define CTF_INFO_KIND(info) (((info) & 0xf800) >> 11) +#define CTF_INFO_ISROOT(info) (((info) & 0x0400) >> 10) +#define CTF_INFO_VLEN(info) (((info) & CTF_MAX_VLEN)) + +#define CTF_TYPE_INFO(kind, isroot, vlen) \\ + (((kind) << 11) | (((isroot) ? 1 : 0) << 10) | ((vlen) & CTF_MAX_VLEN)) +.Ed +.Ss The Label Section +When consuming +.Nm +data, it is often useful to know whether two different +.Nm +containers come from the same source base and version. +For example, when building illumos, there are many kernel modules that are built +against a single collection of source code. +A label is encoded into the +.Nm +files that corresponds with the particular build. +This ensures that if files on the system were to become mixed up from multiple +releases, that they are not used together by tools, particularly when a child +needs to refer to a type in the parent. +Because they are linked using the type identifiers, if the wrong parent is used +then the wrong type will be encountered. +.Lp +Each label is encoded in the file format using the following eight byte +structure: +.Bd -literal +typedef struct ctf_lblent { + uint32_t ctl_label; /* ref to name of label */ + uint32_t ctl_typeidx; /* last type associated with this label */ +} ctf_lblent_t; +.Ed +.Lp +Each label has two different components, a name and a type identifier. +The name is encoded in the +.Em ctl_label +member which is in the format defined in the section +.Sx String Identifiers . +Generally, the names of all labels are found in the internal string +section. +.Lp +The type identifier encoded in the member +.Em ctl_typeidx +refers to the last type identifier that a label refers to in the current +file. +Labels only refer to types in the current file, if the +.Nm +file is a child, then it will have the same label as its parent; +however, its label will only refer to its types, not its parent's. +.Lp +It is also possible, though rather uncommon, for a +.Nm +file to have multiple labels. +Labels are placed one after another, every eight bytes. +When multiple labels are present, types may only belong to a single label. +.Ss The Object Section +The object section provides a mapping from ELF symbols of type +.Sy STT_OBJECT +in the symbol table to a type identifier. +Every entry in this section is a +.Sy uint16_t +which contains a type identifier as described in the section +.Sx Type Identifiers . +If there is no information for an object, then the type identifier 0x0 +is stored for that entry. +.Lp +To walk the object section, you need to have a corresponding +.Sy symbol table +in the ELF object that contains the +.Nm +data. +Not every object is included in this section. +Specifically, when walking the symbol table, an entry is skipped if it matches +any of the following conditions: +.Lp +.Bl -bullet -offset indent -compact +.It +The symbol type is not +.Sy STT_OBJECT +.It +The symbol's section index is +.Sy SHN_UNDEF +.It +The symbol's name offset is zero +.It +The symbol's section index is +.Sy SHN_ABS +and the value of the symbol is zero. +.It +The symbol's name is +.Li _START_ +or +.Li _END_ . +These are skipped because they are used for scoping local symbols in +ELF. +.El +.Lp +The following sample code shows an example of iterating the object +section and skipping the correct symbols: +.Bd -literal +#include <gelf.h> +#include <stdio.h> + +/* + * Given the start of the object section in the CTF file, the number of symbols, + * and the ELF Data sections for the symbol table and the string table, this + * prints the type identifiers that correspond to objects. Note, a more robust + * implementation should ensure that they don't walk beyond the end of the CTF + * object section. + */ +static int +walk_symbols(uint16_t *objtoff, Elf_Data *symdata, Elf_Data *strdata, + long nsyms) +{ + long i; + uintptr_t strbase = strdata->d_buf; + + for (i = 1; i < nsyms; i++, objftoff++) { + const char *name; + GElf_Sym sym; + + if (gelf_getsym(symdata, i, &sym) == NULL) + return (1); + + if (GELF_ST_TYPE(sym.st_info) != STT_OBJECT) + continue; + if (sym.st_shndx == SHN_UNDEF || sym.st_name == 0) + continue; + if (sym.st_shndx == SHN_ABS && sym.st_value == 0) + continue; + name = (const char *)(strbase + sym.st_name); + if (strcmp(name, "_START_") == 0 || strcmp(name, "_END_") == 0) + continue; + + (void) printf("Symbol %d has type %d\n", i, *objtoff); + } + + return (0); +} +.Ed +.Ss The Function Section +The function section of the +.Nm +file encodes the types of both the function's arguments and the function's +return value. +Similar to +.Sx The Object Section , +the function section encodes information for all symbols of type +.Sy STT_FUNCTION , +excepting those that fit specific criteria. +Unlike with objects, because functions have a variable number of arguments, they +start with a type encoding as defined in +.Sx Type Encoding , +which is the size of a +.Sy uint16_t . +For functions which have no type information available, they are encoded as +.Li CTF_TYPE_INFO(CTF_K_UNKNOWN, 0, 0) . +Functions with arguments are encoded differently. +Here, the variable length is turned into the number of arguments in the +function. +If a function is a +.Sy varargs +type function, then the number of arguments is increased by one. +Functions with type information are encoded as: +.Li CTF_TYPE_INFO(CTF_K_FUNCTION, 0, nargs) . +.Lp +For functions that have no type information, nothing else is encoded, and the +next function is encoded. +For functions with type information, the next +.Sy uint16_t +is encoded with the type identifier of the return type of the function. +It is followed by each of the type identifiers of the arguments, if any exist, +in the order that they appear in the function. +Therefore, argument 0 is the first type identifier and so on. +When a function has a final varargs argument, that is encoded with the type +identifier of zero. +.Lp +Like +.Sx The Object Section , +the function section is encoded in the order of the symbol table. +It has similar, but slightly different considerations from objects. +While iterating the symbol table, if any of the following conditions are true, +then the entry is skipped and no corresponding entry is written: +.Lp +.Bl -bullet -offset indent -compact +.It +The symbol type is not +.Sy STT_FUNCTION +.It +The symbol's section index is +.Sy SHN_UNDEF +.It +The symbol's name offset is zero +.It +The symbol's name is +.Li _START_ +or +.Li _END_ . +These are skipped because they are used for scoping local symbols in +ELF. +.El +.Ss The Type Section +The type section is the heart of the +.Nm +data. +It encodes all of the information about the types themselves. +The base of the type information comes in two forms, a short form and a long +form, each of which may be followed by a variable number of arguments. +The following definitions describe the short and long forms: +.Bd -literal +#define CTF_MAX_SIZE 0xfffe /* max size of a type in bytes */ +#define CTF_LSIZE_SENT 0xffff /* sentinel for ctt_size */ +#define CTF_MAX_LSIZE UINT64_MAX + +typedef struct ctf_stype { + uint32_t ctt_name; /* reference to name in string table */ + uint16_t ctt_info; /* encoded kind, variant length */ + union { + uint16_t _size; /* size of entire type in bytes */ + uint16_t _type; /* reference to another type */ + } _u; +} ctf_stype_t; + +typedef struct ctf_type { + uint32_t ctt_name; /* reference to name in string table */ + uint16_t ctt_info; /* encoded kind, variant length */ + union { + uint16_t _size; /* always CTF_LSIZE_SENT */ + uint16_t _type; /* do not use */ + } _u; + uint32_t ctt_lsizehi; /* high 32 bits of type size in bytes */ + uint32_t ctt_lsizelo; /* low 32 bits of type size in bytes */ +} ctf_type_t; + +#define ctt_size _u._size /* for fundamental types that have a size */ +#define ctt_type _u._type /* for types that reference another type */ +.Ed +.Pp +Type sizes are stored in +.Sy bytes . +The basic small form uses a +.Sy uint16_t +to store the number of bytes. +If the number of bytes in a structure would exceed 0xfffe, then the alternate +form, the +.Sy ctf_type_t , +is used instead. +To indicate that the larger form is being used, the member +.Em ctt_size +is set to value of +.Sy CTF_LSIZE_SENT +(0xffff). +In general, when going through the type section, consumers use the +.Sy ctf_type_t +structure, but pay attention to the value of the member +.Em ctt_size +to determine whether they should increment their scan by the size of the +.Sy ctf_stype_t +or +.Sy ctf_type_t . +Not all kinds of types use +.Sy ctt_size . +Those which do not, will always use the +.Sy ctf_stype_t +structure. +The individual sections for each kind have more information. +.Lp +Types are written out in order. +Therefore the first entry encountered has a type id of 0x1, or 0x8000 if a +child. +The member +.Em ctt_name +is encoded as described in the section +.Sx String Identifiers . +The string that it points to is the name of the type. +If the identifier points to an empty string (one that consists solely of a null +terminator) then the type does not have a name, this is common with anonymous +structures and unions that only have a typedef to name them, as well as +pointers and qualifiers. +.Lp +The next member, the +.Em ctt_info , +is encoded as described in the section +.Sx Type Encoding . +The type's kind tells us how to interpret the remaining data in the +.Sy ctf_type_t +and any variable length data that may exist. +The rest of this section will be broken down into the interpretation of the +various kinds. +.Ss Encoding of Integers +Integers, which are of type +.Sy CTF_K_INTEGER , +have no variable length arguments. +Instead, they are followed by a +.Sy uint32_t +which describes their encoding. +All integers must be encoded with a variable length of zero. +The +.Em ctt_size +member describes the length of the integer in bytes. +In general, integer sizes will be rounded up to the closest power of two. +.Lp +The integer encoding contains three different pieces of information: +.Bl -bullet -offset indent -compact +.It +The encoding of the integer +.It +The offset in +.Sy bits +of the type +.It +The size in +.Sy bits +of the type +.El +.Pp +This encoding can be expressed through the following macros: +.Bd -literal -offset indent +#define CTF_INT_ENCODING(data) (((data) & 0xff000000) >> 24) +#define CTF_INT_OFFSET(data) (((data) & 0x00ff0000) >> 16) +#define CTF_INT_BITS(data) (((data) & 0x0000ffff)) + +#define CTF_INT_DATA(encoding, offset, bits) \\ + (((encoding) << 24) | ((offset) << 16) | (bits)) +.Ed +.Pp +The following flags are defined for the encoding at this time: +.Bd -literal -offset indent +#define CTF_INT_SIGNED 0x01 +#define CTF_INT_CHAR 0x02 +#define CTF_INT_BOOL 0x04 +#define CTF_INT_VARARGS 0x08 +.Ed +.Lp +By default, an integer is considered to be unsigned, unless it has the +.Sy CTF_INT_SIGNED +flag set. +If the flag +.Sy CTF_INT_CHAR +is set, that indicates that the integer is of a type that stores character +data, for example the intrinsic C type +.Sy char +would have the +.Sy CTF_INT_CHAR +flag set. +If the flag +.Sy CTF_INT_BOOL +is set, that indicates that the integer represents a boolean type. +For example, the intrinsic C type +.Sy _Bool +would have the +.Sy CTF_INT_BOOL +flag set. +Finally, the flag +.Sy CTF_INT_VARARGS +indicates that the integer is used as part of a variable number of arguments. +This encoding is rather uncommon. +.Ss Encoding of Floats +Floats, which are of type +.Sy CTF_K_FLOAT , +are similar to their integer counterparts. +They have no variable length arguments and are followed by a four byte encoding +which describes the kind of float that exists. +The +.Em ctt_size +member is the size, in bytes, of the float. +The float encoding has three different pieces of information inside of it: +.Lp +.Bl -bullet -offset indent -compact +.It +The specific kind of float that exists +.It +The offset in +.Sy bits +of the float +.It +The size in +.Sy bits +of the float +.El +.Lp +This encoding can be expressed through the following macros: +.Bd -literal -offset indent +#define CTF_FP_ENCODING(data) (((data) & 0xff000000) >> 24) +#define CTF_FP_OFFSET(data) (((data) & 0x00ff0000) >> 16) +#define CTF_FP_BITS(data) (((data) & 0x0000ffff)) + +#define CTF_FP_DATA(encoding, offset, bits) \\ + (((encoding) << 24) | ((offset) << 16) | (bits)) +.Ed +.Lp +Where as the encoding for integers is a series of flags, the encoding for +floats maps to a specific kind of float. +It is not a flag-based value. +The kinds of floats correspond to both their size, and the encoding. +This covers all of the basic C intrinsic floating point types. +The following are the different kinds of floats represented in the encoding: +.Bd -literal -offset indent +#define CTF_FP_SINGLE 1 /* IEEE 32-bit float encoding */ +#define CTF_FP_DOUBLE 2 /* IEEE 64-bit float encoding */ +#define CTF_FP_CPLX 3 /* Complex encoding */ +#define CTF_FP_DCPLX 4 /* Double complex encoding */ +#define CTF_FP_LDCPLX 5 /* Long double complex encoding */ +#define CTF_FP_LDOUBLE 6 /* Long double encoding */ +#define CTF_FP_INTRVL 7 /* Interval (2x32-bit) encoding */ +#define CTF_FP_DINTRVL 8 /* Double interval (2x64-bit) encoding */ +#define CTF_FP_LDINTRVL 9 /* Long double interval (2x128-bit) encoding */ +#define CTF_FP_IMAGRY 10 /* Imaginary (32-bit) encoding */ +#define CTF_FP_DIMAGRY 11 /* Long imaginary (64-bit) encoding */ +#define CTF_FP_LDIMAGRY 12 /* Long double imaginary (128-bit) encoding */ +.Ed +.Ss Encoding of Arrays +Arrays, which are of type +.Sy CTF_K_ARRAY , +have no variable length arguments. +They are followed by a structure which describes the number of elements in the +array, the type identifier of the elements in the array, and the type identifier +of the index of the array. +With arrays, the +.Em ctt_size +member is set to zero. +The structure that follows an array is defined as: +.Bd -literal +typedef struct ctf_array { + uint16_t cta_contents; /* reference to type of array contents */ + uint16_t cta_index; /* reference to type of array index */ + uint32_t cta_nelems; /* number of elements */ +} ctf_array_t; +.Ed +.Lp +The +.Em cta_contents +and +.Em cta_index +members of the +.Sy ctf_array_t +are type identifiers which are encoded as per the section +.Sx Type Identifiers . +The member +.Em cta_nelems +is a simple four byte unsigned count of the number of elements. +This count may be zero when encountering C99's flexible array members. +.Ss Encoding of Functions +Function types, which are of type +.Sy CTF_K_FUNCTION , +use the variable length list to be the number of arguments in the function. +When the function has a final member which is a varargs, then the argument count +is incremented by one to account for the variable argument. +Here, the +.Em ctt_type +member is encoded with the type identifier of the return type of the function. +Note that the +.Em ctt_size +member is not used here. +.Lp +The variable argument list contains the type identifiers for the arguments of +the function, if any. +Each one is represented by a +.Sy uint16_t +and encoded according to the +.Sx Type Identifiers +section. +If the function's last argument is of type varargs, then it is also written out, +but the type identifier is zero. +This is included in the count of the function's arguments. +An extra type identifier may follow the argument and return type identifiers +in order to maintain four-byte alignment for the following type definition. +Such a type identifier is not included in the argument count and has a value +of zero. +.Ss Encoding of Structures and Unions +Structures and Unions, which are encoded with +.Sy CTF_K_STRUCT +and +.Sy CTF_K_UNION +respectively, are very similar constructs in C. +The main difference between them is the fact that members of a structure +follow one another, where as in a union, all members share the same memory. +They are also very similar in terms of their encoding in +.Nm . +The variable length argument for structures and unions represents the number of +members that they have. +The value of the member +.Em ctt_size +is the size of the structure and union. +There are two different structures which are used to encode members in the +variable list. +When the size of a structure or union is greater than or equal to the large +member threshold, 8192, then a different structure is used to encode the member, +all members are encoded using the same structure. +The structure for members is as follows: +.Bd -literal +typedef struct ctf_member { + uint32_t ctm_name; /* reference to name in string table */ + uint16_t ctm_type; /* reference to type of member */ + uint16_t ctm_offset; /* offset of this member in bits */ +} ctf_member_t; + +typedef struct ctf_lmember { + uint32_t ctlm_name; /* reference to name in string table */ + uint16_t ctlm_type; /* reference to type of member */ + uint16_t ctlm_pad; /* padding */ + uint32_t ctlm_offsethi; /* high 32 bits of member offset in bits */ + uint32_t ctlm_offsetlo; /* low 32 bits of member offset in bits */ +} ctf_lmember_t; +.Ed +.Lp +Both the +.Em ctm_name +and +.Em ctlm_name +refer to the name of the member. +The name is encoded as an offset into the string table as described by the +section +.Sx String Identifiers . +The members +.Sy ctm_type +and +.Sy ctlm_type +both refer to the type of the member. +They are encoded as per the section +.Sx Type Identifiers . +.Lp +The last piece of information that is present is the offset which describes the +offset in memory at which the member begins. +For unions, this value will always be zero because each member of a union has +an offset of zero. +For structures, this is the offset in +.Sy bits +at which the member begins. +Note that a compiler may lay out a type with padding. +This means that the difference in offset between two consecutive members may be +larger than the size of the member. +When the size of the overall structure is strictly less than 8192 bytes, the +normal structure, +.Sy ctf_member_t , +is used and the offset in bits is stored in the member +.Em ctm_offset . +However, when the size of the structure is greater than or equal to 8192 bytes, +then the number of bits is split into two 32-bit quantities. +One member, +.Em ctlm_offsethi , +represents the upper 32 bits of the offset, while the other member, +.Em ctlm_offsetlo , +represents the lower 32 bits of the offset. +These can be joined together to get a 64-bit sized offset in bits by shifting +the member +.Em ctlm_offsethi +to the left by thirty two and then doing a binary or of +.Em ctlm_offsetlo . +.Ss Encoding of Enumerations +Enumerations, noted by the type +.Sy CTF_K_ENUM , +are similar to structures. +Enumerations use the variable list to note the number of values that the +enumeration contains, which we'll term enumerators. +In C, an enumeration is always equivalent to the intrinsic type +.Sy int , +thus the value of the member +.Em ctt_size +is always the size of an integer which is determined based on the current model. +For +.Fx +systems, this will always be 4, as an integer is always defined to +be 4 bytes large in both +.Sy ILP32 +and +.Sy LP64 , +regardless of the architecture. +For further details, see +.Xr arch 7 . +.Lp +The enumerators encoded in an enumeration have the following structure in the +variable list: +.Bd -literal +typedef struct ctf_enum { + uint32_t cte_name; /* reference to name in string table */ + int32_t cte_value; /* value associated with this name */ +} ctf_enum_t; +.Ed +.Pp +The member +.Em cte_name +refers to the name of the enumerator's value, it is encoded according to the +rules in the section +.Sx String Identifiers . +The member +.Em cte_value +contains the integer value of this enumerator. +.Ss Encoding of Forward References +Forward references, types of kind +.Sy CTF_K_FORWARD , +in a +.Nm +file refer to types which may not have a definition at all, only a name. +If the +.Nm +file is a child, then it may be that the forward is resolved to an +actual type in the parent, otherwise the definition may be in another +.Nm +container or may not be known at all. +The only member of the +.Sy ctf_type_t +that matters for a forward declaration is the +.Em ctt_name +which points to the name of the forward reference in the string table as +described earlier. +There is no other information recorded for forward references. +.Ss Encoding of Pointers, Typedefs, Volatile, Const, and Restrict +Pointers, typedefs, volatile, const, and restrict are all similar in +.Nm . +They all refer to another type. +In the case of typedefs, they provide an alternate name, while volatile, const, +and restrict change how the type is interpreted in the C programming language. +This covers the +.Nm +kinds +.Sy CTF_K_POINTER , +.Sy CTF_K_TYPEDEF , +.Sy CTF_K_VOLATILE , +.Sy CTF_K_RESTRICT , +and +.Sy CTF_K_CONST . +.Lp +These types have no variable list entries and use the member +.Em ctt_type +to refer to the base type that they modify. +.Ss Encoding of Unknown Types +Types with the kind +.Sy CTF_K_UNKNOWN +are used to indicate gaps in the type identifier space. +These entries consume an identifier, but do not define anything. +Nothing should refer to these gap identifiers. +.Ss Dependencies Between Types +C types can be imagined as a directed, cyclic, graph. +Structures and unions may refer to each other in a way that creates a cyclic +dependency. +In cases such as these, the entire type section must be read in and processed. +Consumers must not assume that every type can be laid out in dependency order; +they cannot. +.Ss The String Section +The last section of the +.Nm +file is the +.Sy string +section. +This section encodes all of the strings that appear throughout the other +sections. +It is laid out as a series of characters followed by a null terminator. +Generally, all names are written out in ASCII, as most C compilers do not allow +any characters to appear in identifiers outside of a subset of ASCII. +However, any extended characters sets should be written out as a series of UTF-8 +bytes. +.Lp +The first entry in the section, at offset zero, is a single null +terminator to reference the empty string. +Following that, each C string should be written out, including the null +terminator. +Offsets that refer to something in this section should refer to the first byte +which begins a string. +Beyond the first byte in the section being the null terminator, the order of +strings is unimportant. +.Ss Data Encoding and ELF Considerations +.Nm +data is generally included in ELF objects which specify information to +identify the architecture and endianness of the file. +A +.Nm +container inside such an object must match the endianness of the ELF object. +Aside from the question of the endian encoding of data, there should be no other +differences between architectures. +While many of the types in this document refer to non-fixed size C integral +types, they are equivalent in the models +.Sy ILP32 +and +.Sy LP64 . +If any other model is being used with +.Nm +data that has different sizes, then it must not use the model's sizes for +those integral types and instead use the fixed size equivalents based on an +.Sy ILP32 +environment. +.Lp +When placing a +.Nm +container inside of an ELF object, there are certain conventions that are +expected for the purposes of tooling being able to find the +.Nm +data. +In particular, a given ELF object should only contain a single +.Nm +section. +Multiple containers should be merged together into a single one. +.Lp +The +.Nm +file should be included in its own ELF section. +The section's name must be +.Ql .SUNW_ctf . +The type of the section must be +.Sy SHT_PROGBITS . +The section should have a link set to the symbol table and its address +alignment must be 4. +.Sh SEE ALSO +.Xr dtrace 1 , +.Xr elf 3 , +.Xr gelf 3 , +.Xr a.out 5 , +.Xr elf 5 , +.Xr arch 7 diff --git a/cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c b/cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c new file mode 100644 index 000000000000..c35b1a526d21 --- /dev/null +++ b/cddl/contrib/opensolaris/lib/libctf/common/ctf_lib.c @@ -0,0 +1,528 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License, Version 1.0 only + * (the "License"). You may not use this file except in compliance + * with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2003 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <sys/types.h> +#include <sys/stat.h> +#include <sys/mman.h> +#include <sys/zmod.h> +#include <ctf_impl.h> +#include <unistd.h> +#include <fcntl.h> +#include <errno.h> +#ifdef illumos +#include <dlfcn.h> +#else +#include <zlib.h> +#endif +#include <gelf.h> + +#ifdef illumos +#ifdef _LP64 +static const char *_libctf_zlib = "/usr/lib/64/libz.so"; +#else +static const char *_libctf_zlib = "/usr/lib/libz.so"; +#endif +#endif + +static struct { + int (*z_uncompress)(uchar_t *, ulong_t *, const uchar_t *, ulong_t); + const char *(*z_error)(int); + void *z_dlp; +} zlib; + +static size_t _PAGESIZE; +static size_t _PAGEMASK; + +#ifdef illumos +#pragma init(_libctf_init) +#else +void _libctf_init(void) __attribute__ ((constructor)); +#endif +void +_libctf_init(void) +{ +#ifdef illumos + const char *p = getenv("LIBCTF_DECOMPRESSOR"); + + if (p != NULL) + _libctf_zlib = p; /* use alternate decompression library */ +#endif + + _libctf_debug = getenv("LIBCTF_DEBUG") != NULL; + + _PAGESIZE = getpagesize(); + _PAGEMASK = ~(_PAGESIZE - 1); +} + +/* + * Attempt to dlopen the decompression library and locate the symbols of + * interest that we will need to call. This information in cached so + * that multiple calls to ctf_bufopen() do not need to reopen the library. + */ +void * +ctf_zopen(int *errp) +{ +#ifdef illumos + ctf_dprintf("decompressing CTF data using %s\n", _libctf_zlib); + + if (zlib.z_dlp != NULL) + return (zlib.z_dlp); /* library is already loaded */ + + if (access(_libctf_zlib, R_OK) == -1) + return (ctf_set_open_errno(errp, ECTF_ZMISSING)); + + if ((zlib.z_dlp = dlopen(_libctf_zlib, RTLD_LAZY | RTLD_LOCAL)) == NULL) + return (ctf_set_open_errno(errp, ECTF_ZINIT)); + + zlib.z_uncompress = (int (*)(uchar_t *, ulong_t *, const uchar_t *, ulong_t)) dlsym(zlib.z_dlp, "uncompress"); + zlib.z_error = (const char *(*)(int)) dlsym(zlib.z_dlp, "zError"); + + if (zlib.z_uncompress == NULL || zlib.z_error == NULL) { + (void) dlclose(zlib.z_dlp); + bzero(&zlib, sizeof (zlib)); + return (ctf_set_open_errno(errp, ECTF_ZINIT)); + } +#else + zlib.z_uncompress = uncompress; + zlib.z_error = zError; + + /* Dummy return variable as 'no error' */ + zlib.z_dlp = (void *) (uintptr_t) 1; +#endif + + return (zlib.z_dlp); +} + +/* + * The ctf_bufopen() routine calls these subroutines, defined by <sys/zmod.h>, + * which we then patch through to the functions in the decompression library. + */ +int +z_uncompress(void *dst, size_t *dstlen, const void *src, size_t srclen) +{ + return (zlib.z_uncompress(dst, (ulong_t *)dstlen, src, srclen)); +} + +const char * +z_strerror(int err) +{ + return (zlib.z_error(err)); +} + +/* + * Convert a 32-bit ELF file header into GElf. + */ +static void +ehdr_to_gelf(const Elf32_Ehdr *src, GElf_Ehdr *dst) +{ + bcopy(src->e_ident, dst->e_ident, EI_NIDENT); + dst->e_type = src->e_type; + dst->e_machine = src->e_machine; + dst->e_version = src->e_version; + dst->e_entry = (Elf64_Addr)src->e_entry; + dst->e_phoff = (Elf64_Off)src->e_phoff; + dst->e_shoff = (Elf64_Off)src->e_shoff; + dst->e_flags = src->e_flags; + dst->e_ehsize = src->e_ehsize; + dst->e_phentsize = src->e_phentsize; + dst->e_phnum = src->e_phnum; + dst->e_shentsize = src->e_shentsize; + dst->e_shnum = src->e_shnum; + dst->e_shstrndx = src->e_shstrndx; +} + +/* + * Convert a 32-bit ELF section header into GElf. + */ +static void +shdr_to_gelf(const Elf32_Shdr *src, GElf_Shdr *dst) +{ + dst->sh_name = src->sh_name; + dst->sh_type = src->sh_type; + dst->sh_flags = src->sh_flags; + dst->sh_addr = src->sh_addr; + dst->sh_offset = src->sh_offset; + dst->sh_size = src->sh_size; + dst->sh_link = src->sh_link; + dst->sh_info = src->sh_info; + dst->sh_addralign = src->sh_addralign; + dst->sh_entsize = src->sh_entsize; +} + +/* + * In order to mmap a section from the ELF file, we must round down sh_offset + * to the previous page boundary, and mmap the surrounding page. We store + * the pointer to the start of the actual section data back into sp->cts_data. + */ +const void * +ctf_sect_mmap(ctf_sect_t *sp, int fd) +{ + size_t pageoff = sp->cts_offset & ~_PAGEMASK; + + caddr_t base = mmap64(NULL, sp->cts_size + pageoff, PROT_READ, + MAP_PRIVATE, fd, sp->cts_offset & _PAGEMASK); + + if (base != MAP_FAILED) + sp->cts_data = base + pageoff; + + return (base); +} + +/* + * Since sp->cts_data has the adjusted offset, we have to again round down + * to get the actual mmap address and round up to get the size. + */ +void +ctf_sect_munmap(const ctf_sect_t *sp) +{ + uintptr_t addr = (uintptr_t)sp->cts_data; + uintptr_t pageoff = addr & ~_PAGEMASK; + + (void) munmap((void *)(addr - pageoff), sp->cts_size + pageoff); +} + +/* + * Open the specified file descriptor and return a pointer to a CTF container. + * The file can be either an ELF file or raw CTF file. The caller is + * responsible for closing the file descriptor when it is no longer needed. + */ +ctf_file_t * +ctf_fdopen(int fd, int *errp) +{ + ctf_sect_t ctfsect, symsect, strsect; + ctf_file_t *fp = NULL; + size_t shstrndx, shnum; + + struct stat64 st; + ssize_t nbytes; + + union { + ctf_preamble_t ctf; + Elf32_Ehdr e32; + GElf_Ehdr e64; + } hdr; + + bzero(&ctfsect, sizeof (ctf_sect_t)); + bzero(&symsect, sizeof (ctf_sect_t)); + bzero(&strsect, sizeof (ctf_sect_t)); + bzero(&hdr, sizeof (hdr)); + + if (fstat64(fd, &st) == -1) + return (ctf_set_open_errno(errp, errno)); + + if ((nbytes = pread64(fd, &hdr, sizeof (hdr), 0)) <= 0) + return (ctf_set_open_errno(errp, nbytes < 0? errno : ECTF_FMT)); + + /* + * If we have read enough bytes to form a CTF header and the magic + * string matches, attempt to interpret the file as raw CTF. + */ + if (nbytes >= (ssize_t) sizeof (ctf_preamble_t) && + hdr.ctf.ctp_magic == CTF_MAGIC) { + if (hdr.ctf.ctp_version > CTF_VERSION) + return (ctf_set_open_errno(errp, ECTF_CTFVERS)); + + ctfsect.cts_data = mmap64(NULL, st.st_size, PROT_READ, + MAP_PRIVATE, fd, 0); + + if (ctfsect.cts_data == MAP_FAILED) + return (ctf_set_open_errno(errp, errno)); + + ctfsect.cts_name = _CTF_SECTION; + ctfsect.cts_type = SHT_PROGBITS; + ctfsect.cts_flags = SHF_ALLOC; + ctfsect.cts_size = (size_t)st.st_size; + ctfsect.cts_entsize = 1; + ctfsect.cts_offset = 0; + + if ((fp = ctf_bufopen(&ctfsect, NULL, NULL, errp)) == NULL) + ctf_sect_munmap(&ctfsect); + + return (fp); + } + + /* + * If we have read enough bytes to form an ELF header and the magic + * string matches, attempt to interpret the file as an ELF file. We + * do our own largefile ELF processing, and convert everything to + * GElf structures so that clients can operate on any data model. + */ + if (nbytes >= (ssize_t) sizeof (Elf32_Ehdr) && + bcmp(&hdr.e32.e_ident[EI_MAG0], ELFMAG, SELFMAG) == 0) { +#if BYTE_ORDER == _BIG_ENDIAN + uchar_t order = ELFDATA2MSB; +#else + uchar_t order = ELFDATA2LSB; +#endif + GElf_Shdr *sp; + + void *strs_map; + size_t strs_mapsz, i; + char *strs; + + if (hdr.e32.e_ident[EI_DATA] != order) + return (ctf_set_open_errno(errp, ECTF_ENDIAN)); + if (hdr.e32.e_version != EV_CURRENT) + return (ctf_set_open_errno(errp, ECTF_ELFVERS)); + + if (hdr.e32.e_ident[EI_CLASS] == ELFCLASS64) { + if (nbytes < (ssize_t) sizeof (GElf_Ehdr)) + return (ctf_set_open_errno(errp, ECTF_FMT)); + } else { + Elf32_Ehdr e32 = hdr.e32; + ehdr_to_gelf(&e32, &hdr.e64); + } + + shnum = hdr.e64.e_shnum; + shstrndx = hdr.e64.e_shstrndx; + + /* Extended ELF sections */ + if ((shstrndx == SHN_XINDEX) || (shnum == 0)) { + if (hdr.e32.e_ident[EI_CLASS] == ELFCLASS32) { + Elf32_Shdr x32; + + if (pread64(fd, &x32, sizeof (x32), + hdr.e64.e_shoff) != sizeof (x32)) + return (ctf_set_open_errno(errp, + errno)); + + shnum = x32.sh_size; + shstrndx = x32.sh_link; + } else { + Elf64_Shdr x64; + + if (pread64(fd, &x64, sizeof (x64), + hdr.e64.e_shoff) != sizeof (x64)) + return (ctf_set_open_errno(errp, + errno)); + + shnum = x64.sh_size; + shstrndx = x64.sh_link; + } + } + + if (shstrndx >= shnum) + return (ctf_set_open_errno(errp, ECTF_CORRUPT)); + + nbytes = sizeof (GElf_Shdr) * shnum; + + if ((sp = malloc(nbytes)) == NULL) + return (ctf_set_open_errno(errp, errno)); + + /* + * Read in and convert to GElf the array of Shdr structures + * from e_shoff so we can locate sections of interest. + */ + if (hdr.e32.e_ident[EI_CLASS] == ELFCLASS32) { + Elf32_Shdr *sp32; + + nbytes = sizeof (Elf32_Shdr) * shnum; + + if ((sp32 = malloc(nbytes)) == NULL || pread64(fd, + sp32, nbytes, hdr.e64.e_shoff) != nbytes) { + free(sp); + free(sp32); + return (ctf_set_open_errno(errp, errno)); + } + + for (i = 0; i < shnum; i++) + shdr_to_gelf(&sp32[i], &sp[i]); + + free(sp32); + + } else if (pread64(fd, sp, nbytes, hdr.e64.e_shoff) != nbytes) { + free(sp); + return (ctf_set_open_errno(errp, errno)); + } + + /* + * Now mmap the section header strings section so that we can + * perform string comparison on the section names. + */ + strs_mapsz = sp[shstrndx].sh_size + + (sp[shstrndx].sh_offset & ~_PAGEMASK); + + strs_map = mmap64(NULL, strs_mapsz, PROT_READ, MAP_PRIVATE, + fd, sp[shstrndx].sh_offset & _PAGEMASK); + + strs = (char *)strs_map + + (sp[shstrndx].sh_offset & ~_PAGEMASK); + + if (strs_map == MAP_FAILED) { + free(sp); + return (ctf_set_open_errno(errp, ECTF_MMAP)); + } + + /* + * Iterate over the section header array looking for the CTF + * section and symbol table. The strtab is linked to symtab. + */ + for (i = 0; i < shnum; i++) { + const GElf_Shdr *shp = &sp[i]; + const GElf_Shdr *lhp = &sp[shp->sh_link]; + + if (shp->sh_link >= shnum) + continue; /* corrupt sh_link field */ + + if (shp->sh_name >= sp[shstrndx].sh_size || + lhp->sh_name >= sp[shstrndx].sh_size) + continue; /* corrupt sh_name field */ + + if (shp->sh_type == SHT_PROGBITS && + strcmp(strs + shp->sh_name, _CTF_SECTION) == 0) { + ctfsect.cts_name = strs + shp->sh_name; + ctfsect.cts_type = shp->sh_type; + ctfsect.cts_flags = shp->sh_flags; + ctfsect.cts_size = shp->sh_size; + ctfsect.cts_entsize = shp->sh_entsize; + ctfsect.cts_offset = (off64_t)shp->sh_offset; + + } else if (shp->sh_type == SHT_SYMTAB) { + symsect.cts_name = strs + shp->sh_name; + symsect.cts_type = shp->sh_type; + symsect.cts_flags = shp->sh_flags; + symsect.cts_size = shp->sh_size; + symsect.cts_entsize = shp->sh_entsize; + symsect.cts_offset = (off64_t)shp->sh_offset; + + strsect.cts_name = strs + lhp->sh_name; + strsect.cts_type = lhp->sh_type; + strsect.cts_flags = lhp->sh_flags; + strsect.cts_size = lhp->sh_size; + strsect.cts_entsize = lhp->sh_entsize; + strsect.cts_offset = (off64_t)lhp->sh_offset; + } + } + + free(sp); /* free section header array */ + + if (ctfsect.cts_type == SHT_NULL) { + (void) munmap(strs_map, strs_mapsz); + return (ctf_set_open_errno(errp, ECTF_NOCTFDATA)); + } + + /* + * Now mmap the CTF data, symtab, and strtab sections and + * call ctf_bufopen() to do the rest of the work. + */ + if (ctf_sect_mmap(&ctfsect, fd) == MAP_FAILED) { + (void) munmap(strs_map, strs_mapsz); + return (ctf_set_open_errno(errp, ECTF_MMAP)); + } + + if (symsect.cts_type != SHT_NULL && + strsect.cts_type != SHT_NULL) { + if (ctf_sect_mmap(&symsect, fd) == MAP_FAILED || + ctf_sect_mmap(&strsect, fd) == MAP_FAILED) { + (void) ctf_set_open_errno(errp, ECTF_MMAP); + goto bad; /* unmap all and abort */ + } + fp = ctf_bufopen(&ctfsect, &symsect, &strsect, errp); + } else + fp = ctf_bufopen(&ctfsect, NULL, NULL, errp); +bad: + if (fp == NULL) { + ctf_sect_munmap(&ctfsect); + ctf_sect_munmap(&symsect); + ctf_sect_munmap(&strsect); + } else + fp->ctf_flags |= LCTF_MMAP; + + (void) munmap(strs_map, strs_mapsz); + return (fp); + } + + return (ctf_set_open_errno(errp, ECTF_FMT)); +} + +/* + * Open the specified file and return a pointer to a CTF container. The file + * can be either an ELF file or raw CTF file. This is just a convenient + * wrapper around ctf_fdopen() for callers. + */ +ctf_file_t * +ctf_open(const char *filename, int *errp) +{ + ctf_file_t *fp; + int fd; + + if ((fd = open64(filename, O_RDONLY)) == -1) { + if (errp != NULL) + *errp = errno; + return (NULL); + } + + fp = ctf_fdopen(fd, errp); + (void) close(fd); + return (fp); +} + +/* + * Write the uncompressed CTF data stream to the specified file descriptor. + * This is useful for saving the results of dynamic CTF containers. + */ +int +ctf_write(ctf_file_t *fp, int fd) +{ + const uchar_t *buf = fp->ctf_base; + ssize_t resid = fp->ctf_size; + ssize_t len; + + while (resid != 0) { + if ((len = write(fd, buf, resid)) <= 0) + return (ctf_set_errno(fp, errno)); + resid -= len; + buf += len; + } + + return (0); +} + +/* + * Set the CTF library client version to the specified version. If version is + * zero, we just return the default library version number. + */ +int +ctf_version(int version) +{ + if (version < 0) { + errno = EINVAL; + return (-1); + } + + if (version > 0) { + if (version > CTF_VERSION) { + errno = ENOTSUP; + return (-1); + } + ctf_dprintf("ctf_version: client using version %d\n", version); + _libctf_version = version; + } + + return (_libctf_version); +} diff --git a/cddl/contrib/opensolaris/lib/libctf/common/ctf_subr.c b/cddl/contrib/opensolaris/lib/libctf/common/ctf_subr.c new file mode 100644 index 000000000000..e9f5ad7a1f71 --- /dev/null +++ b/cddl/contrib/opensolaris/lib/libctf/common/ctf_subr.c @@ -0,0 +1,83 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License, Version 1.0 only + * (the "License"). You may not use this file except in compliance + * with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2003 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <ctf_impl.h> +#include <sys/mman.h> +#include <stdarg.h> + +void * +ctf_data_alloc(size_t size) +{ + return (mmap(NULL, size, PROT_READ | PROT_WRITE, + MAP_PRIVATE | MAP_ANON, -1, 0)); +} + +void +ctf_data_free(void *buf, size_t size) +{ + (void) munmap(buf, size); +} + +void +ctf_data_protect(void *buf, size_t size) +{ + (void) mprotect(buf, size, PROT_READ); +} + +void * +ctf_alloc(size_t size) +{ + return (malloc(size)); +} + +/*ARGSUSED*/ +void +ctf_free(void *buf, __unused size_t size) +{ + free(buf); +} + +const char * +ctf_strerror(int err) +{ + return ((const char *) strerror(err)); +} + +/*PRINTFLIKE1*/ +void +ctf_dprintf(const char *format, ...) +{ + if (_libctf_debug) { + va_list alist; + + va_start(alist, format); + (void) fputs("libctf DEBUG: ", stderr); + (void) vfprintf(stderr, format, alist); + va_end(alist); + } +} diff --git a/cddl/contrib/opensolaris/lib/libctf/common/libctf.h b/cddl/contrib/opensolaris/lib/libctf/common/libctf.h new file mode 100644 index 000000000000..3fd69318ded0 --- /dev/null +++ b/cddl/contrib/opensolaris/lib/libctf/common/libctf.h @@ -0,0 +1,60 @@ +/* + * CDDL HEADER START + * + * The contents of this file are subject to the terms of the + * Common Development and Distribution License, Version 1.0 only + * (the "License"). You may not use this file except in compliance + * with the License. + * + * You can obtain a copy of the license at usr/src/OPENSOLARIS.LICENSE + * or http://www.opensolaris.org/os/licensing. + * See the License for the specific language governing permissions + * and limitations under the License. + * + * When distributing Covered Code, include this CDDL HEADER in each + * file and include the License file at usr/src/OPENSOLARIS.LICENSE. + * If applicable, add the following below this CDDL HEADER, with the + * fields enclosed by brackets "[]" replaced with your own identifying + * information: Portions Copyright [yyyy] [name of copyright owner] + * + * CDDL HEADER END + */ +/* + * Copyright 2001-2003 Sun Microsystems, Inc. All rights reserved. + * Use is subject to license terms. + */ + +/* + * This header file defines the interfaces available from the CTF debugger + * library, libctf. This library provides functions that a debugger can + * use to operate on data in the Compact ANSI-C Type Format (CTF). This + * is NOT a public interface, although it may eventually become one in + * the fullness of time after we gain more experience with the interfaces. + * + * In the meantime, be aware that any program linked with libctf in this + * release of Solaris is almost guaranteed to break in the next release. + * + * In short, do not user this header file or libctf for any purpose. + */ + +#ifndef _LIBCTF_H +#define _LIBCTF_H + +#pragma ident "%Z%%M% %I% %E% SMI" + +#include <sys/ctf_api.h> + +#ifdef __cplusplus +extern "C" { +#endif + +/* + * This flag can be used to enable debug messages. + */ +extern int _libctf_debug; + +#ifdef __cplusplus +} +#endif + +#endif /* _LIBCTF_H */ |