WebSVN – HelenOS – Diff – /branches/dynload/uspace/srv/loader/elf_load.c


/*
 * Copyright (c) 2006 Sergey Bondari
 * Copyright (c) 2006 Jakub Jermar
 * Copyright (c) 2008 Jiri Svoboda
 * All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 *
 * - Redistributions of source code must retain the above copyright
 *   notice, this list of conditions and the following disclaimer.
 * - Redistributions in binary form must reproduce the above copyright
 *   notice, this list of conditions and the following disclaimer in the
 *   documentation and/or other materials provided with the distribution.
 * - The name of the author may not be used to endorse or promote products
 *   derived from this software without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
 * IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
 * OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
 * IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
 * INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
 * NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
 * DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
 * THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
 * (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
 * THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
 */
 
/** @addtogroup generic
 * @{
 */
 
/**
 * @file
 * @brief   Userspace ELF loader.
 *
 * This module allows loading ELF binaries (both executables and
 * shared objects) from VFS. The current implementation allocates
 * anonymous memory, fills it with segment data and then adjusts
 * the memory areas' flags to the final value. In the future,
 * the segments will be mapped directly from the file.
 */
 
#include <stdio.h>
#include <sys/types.h>
#include <align.h>
#include <assert.h>
#include <as.h>
#include <unistd.h>
#include <fcntl.h>
#include <loader/pcb.h>
 
#include "elf.h"
 
#include "elf_load.h"
#include "arch.h"
 
static char *error_codes[] = {
    "no error",
    "invalid image",
    "address space error",
    "incompatible image",
    "unsupported image type",
    "irrecoverable error"
};
 
static unsigned int elf_load(elf_ld_t *elf, size_t so_bias);
static int segment_header(elf_ld_t *elf, elf_segment_header_t *entry);
static int section_header(elf_ld_t *elf, elf_section_header_t *entry);
static int load_segment(elf_ld_t *elf, elf_segment_header_t *entry);
 
/** Load ELF binary from a file.
 *
 * Load an ELF binary from the specified file. If the file is
 * an executable program, it is loaded unbiased. If it is a shared
 * object, it is loaded with the bias @a so_bias. Some information
 * extracted from the binary is stored in a elf_info_t structure
 * pointed to by @a info.
 *
 * @param file_name Path to the ELF file.
 * @param so_bias   Bias to use if the file is a shared object.
 * @param info      Pointer to a structure for storing information
 *          extracted from the binary.
 *
 * @return EOK on success or negative error code.
 */
int elf_load_file(char *file_name, size_t so_bias, elf_info_t *info)
{
    elf_ld_t elf;
 
    int fd;
    int rc;
 
//  printf("open and read '%s'...\n", file_name);
 
    fd = open(file_name, O_RDONLY);
    if (fd < 0) {
        printf("failed opening file\n");
        return -1;
    }
 
    elf.fd = fd;
    elf.info = info;
 
    rc = elf_load(&elf, so_bias);
 
    close(fd);
 
    return rc;
}
 
/** Run an ELF executable.
 *
 * Transfers control to the entry point of an ELF executable loaded
 * earlier with elf_load_file(). This function does not return.
 *
 * @param info  Info structure filled earlier by elf_load_file()
 */
void elf_run(elf_info_t *info, pcb_t *pcb)
{
    program_run(info->entry, pcb);
 
    /* not reached */
}
 
/** Create the program control block (PCB).
 *
 * Fills the program control block @a pcb with information from
 * @a info.
 *
 * @param info  Program info structure
 * @return EOK on success or negative error code
 */
void elf_create_pcb(elf_info_t *info, pcb_t *pcb)
{
 
 
 
 
 
 
 
 
 
 
 
    pcb->entry = info->entry;
    pcb->dynamic = info->dynamic;
 
 
}
 
 
/** Load an ELF binary.
 *
 * The @a elf structure contains the loader state, including
 * an open file, from which the binary will be loaded,
 * a pointer to the @c info structure etc.
 *
 * @param elf       Pointer to loader state buffer.
 * @param so_bias   Bias to use if the file is a shared object.
 * @return EE_OK on success or EE_xx error code.
 */
static unsigned int elf_load(elf_ld_t *elf, size_t so_bias)
{
    elf_header_t header_buf;
    elf_header_t *header = &header_buf;
    int i, rc;
 
    rc = read(elf->fd, header, sizeof(elf_header_t));
    if (rc < 0) {
        printf("read error\n");
        return EE_INVALID;
    }
 
    elf->header = header;
 
//  printf("ELF-load:");
    /* Identify ELF */
    if (header->e_ident[EI_MAG0] != ELFMAG0 ||
        header->e_ident[EI_MAG1] != ELFMAG1 ||
        header->e_ident[EI_MAG2] != ELFMAG2 ||
        header->e_ident[EI_MAG3] != ELFMAG3) {
        printf("invalid header\n");
        return EE_INVALID;
    }
   
    /* Identify ELF compatibility */
    if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING ||
        header->e_machine != ELF_MACHINE ||
        header->e_ident[EI_VERSION] != EV_CURRENT ||
        header->e_version != EV_CURRENT ||
        header->e_ident[EI_CLASS] != ELF_CLASS) {
        printf("incompatible data/version/class\n");
        return EE_INCOMPATIBLE;
    }
 
    if (header->e_phentsize != sizeof(elf_segment_header_t)) {
        printf("e_phentsize:%d != %d\n", header->e_phentsize,
            sizeof(elf_segment_header_t));
        return EE_INCOMPATIBLE;
    }
 
    if (header->e_shentsize != sizeof(elf_section_header_t)) {
        printf("e_shentsize:%d != %d\n", header->e_shentsize,
            sizeof(elf_section_header_t));
        return EE_INCOMPATIBLE;
    }
 
    /* Check if the object type is supported. */
    if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {
        printf("Object type %d is not supported\n", header->e_type);
        return EE_UNSUPPORTED;
    }
 
    /* Shared objects can be loaded with a bias */
//  printf("Object type: %d\n", header->e_type);
    if (header->e_type == ET_DYN)
        elf->bias = so_bias;
    else
        elf->bias = 0;
 
//  printf("Bias set to 0x%x\n", elf->bias);
    elf->info->interp = NULL;
    elf->info->dynamic = NULL;
 
//  printf("parse segments\n");
 
    /* Walk through all segment headers and process them. */
    for (i = 0; i < header->e_phnum; i++) {
        elf_segment_header_t segment_hdr;
 
        /* Seek to start of segment header */
        lseek(elf->fd, header->e_phoff
                + i * sizeof(elf_segment_header_t), SEEK_SET);
 
        rc = read(elf->fd, &segment_hdr, sizeof(elf_segment_header_t));
        if (rc < 0) { printf("read error\n"); return EE_INVALID; }
 
        rc = segment_header(elf, &segment_hdr);
        if (rc != EE_OK)
            return rc;
    }
 
//  printf("parse sections\n");
 
    /* Inspect all section headers and proccess them. */
    for (i = 0; i < header->e_shnum; i++) {
        elf_section_header_t section_hdr;
 
        /* Seek to start of section header */
        lseek(elf->fd, header->e_shoff
            + i * sizeof(elf_section_header_t), SEEK_SET);
 
        rc = read(elf->fd, &section_hdr, sizeof(elf_section_header_t));
        if (rc < 0) { printf("read error\n"); return EE_INVALID; }
 
        rc = section_header(elf, &section_hdr);
        if (rc != EE_OK)
            return rc;
    }
 
    elf->info->entry =
        (entry_point_t)((uint8_t *)header->e_entry + elf->bias);
 
//  printf("done\n");
 
    return EE_OK;
}
 
/** Print error message according to error code.
 *
 * @param rc Return code returned by elf_load().
 *
 * @return NULL terminated description of error.
 */
char *elf_error(unsigned int rc)
{
    assert(rc < sizeof(error_codes) / sizeof(char *));
 
    return error_codes[rc];
}
 
/** Process segment header.
 *
 * @param entry Segment header.
 *
 * @return EE_OK on success, error code otherwise.
 */
static int segment_header(elf_ld_t *elf, elf_segment_header_t *entry)
{
    switch (entry->p_type) {
    case PT_NULL:
    case PT_PHDR:
        break;
    case PT_LOAD:
        return load_segment(elf, entry);
        break;
    case PT_INTERP:
        /* Assume silently interp == "/rtld.so" */
        elf->info->interp = "/rtld.so";
        break;
    case PT_DYNAMIC:
    case PT_SHLIB:
    case PT_NOTE:
    case PT_LOPROC:
    case PT_HIPROC:
    default:
        printf("segment p_type %d unknown\n", entry->p_type);
        return EE_UNSUPPORTED;
        break;
    }
    return EE_OK;
}
 
/** Load segment described by program header entry.
 *
 * @param elf   Loader state.
 * @param entry Program header entry describing segment to be loaded.
 *
 * @return EE_OK on success, error code otherwise.
 */
int load_segment(elf_ld_t *elf, elf_segment_header_t *entry)
{
    void *a;
    int flags = 0;
    uintptr_t bias;
    uintptr_t base;
    size_t mem_sz;
    int rc;
 
//  printf("load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,
//      entry->p_memsz);
   
    bias = elf->bias;
 
    if (entry->p_align > 1) {
        if ((entry->p_offset % entry->p_align) !=
            (entry->p_vaddr % entry->p_align)) {
            printf("align check 1 failed offset%%align=%d, vaddr%%align=%d\n",
            entry->p_offset % entry->p_align,
            entry->p_vaddr % entry->p_align
            );
            return EE_INVALID;
        }
    }
 
    /* Final flags that will be set for the memory area */
 
    if (entry->p_flags & PF_X)
        flags |= AS_AREA_EXEC;
    if (entry->p_flags & PF_W)
        flags |= AS_AREA_WRITE;
    if (entry->p_flags & PF_R)
        flags |= AS_AREA_READ;
    flags |= AS_AREA_CACHEABLE;
   
    base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);
    mem_sz = entry->p_memsz + (entry->p_vaddr - base);
 
//  printf("map to p_vaddr=0x%x-0x%x...\n", entry->p_vaddr + bias,
//  entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));
 
    /*
     * For the course of loading, the area needs to be readable
     * and writeable.
     */
    a = as_area_create((uint8_t *)base + bias,
        mem_sz, AS_AREA_READ | AS_AREA_WRITE | AS_AREA_CACHEABLE);
    if (a == (void *)(-1)) {
        printf("memory mapping failed\n");
        return EE_MEMORY;
    }
 
//  printf("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",
//      entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);
 
    /*
     * Load segment data
     */
//  printf("seek to %d\n", entry->p_offset);
    rc = lseek(elf->fd, entry->p_offset, SEEK_SET);
    if (rc < 0) { printf("seek error\n"); return EE_INVALID; }
 
//  printf("read 0x%x bytes to address 0x%x\n", entry->p_filesz, entry->p_vaddr+bias);
/*  rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);
    if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/
 
    /* Long reads are not possible yet. Load segment picewise */
 
    unsigned left, now;
    uint8_t *dp;
 
    left = entry->p_filesz;
    dp = (uint8_t *)(entry->p_vaddr + bias);
 
    while (left > 0) {
        now = 16384;
        if (now > left) now = left;
 
//      printf("read %d...", now);
        rc = read(elf->fd, dp, now);
//      printf("->%d\n", rc);
 
        if (rc < 0) { printf("read error\n"); return EE_INVALID; }
 
        left -= now;
        dp += now;
    }
 
//  printf("set area flags to %d\n", flags);
    rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);
    if (rc != 0) {
        printf("failed to set memory area flags\n");
        return EE_MEMORY;
    }
 
    return EE_OK;
}
 
/** Process section header.
 *
 * @param elf   Loader state.
 * @param entry Segment header.
 *
 * @return EE_OK on success, error code otherwise.
 */
static int section_header(elf_ld_t *elf, elf_section_header_t *entry)
{
    switch (entry->sh_type) {
    case SHT_PROGBITS:
        if (entry->sh_flags & SHF_TLS) {
            /* .tdata */
        }
        break;
    case SHT_NOBITS:
        if (entry->sh_flags & SHF_TLS) {
            /* .tbss */
        }
        break;
    case SHT_DYNAMIC:
        /* Record pointer to dynamic section into info structure */
        elf->info->dynamic =
            (void *)((uint8_t *)entry->sh_addr + elf->bias);
        printf("dynamic section found at 0x%x\n",
            (uintptr_t)elf->info->dynamic);
        break;
    default:
        break;
    }
   
    return EE_OK;
}
 
/** @}
 */
 

Rev 3169	Rev 3170
1	/*	1	/*
2	* Copyright (c) 2006 Sergey Bondari	2	* Copyright (c) 2006 Sergey Bondari
3	* Copyright (c) 2006 Jakub Jermar	3	* Copyright (c) 2006 Jakub Jermar
4	* Copyright (c) 2008 Jiri Svoboda	4	* Copyright (c) 2008 Jiri Svoboda
5	* All rights reserved.	5	* All rights reserved.
6	*	6	*
7	* Redistribution and use in source and binary forms, with or without	7	* Redistribution and use in source and binary forms, with or without
8	* modification, are permitted provided that the following conditions	8	* modification, are permitted provided that the following conditions
9	* are met:	9	* are met:
10	*	10	*
11	* - Redistributions of source code must retain the above copyright	11	* - Redistributions of source code must retain the above copyright
12	* notice, this list of conditions and the following disclaimer.	12	* notice, this list of conditions and the following disclaimer.
13	* - Redistributions in binary form must reproduce the above copyright	13	* - Redistributions in binary form must reproduce the above copyright
14	* notice, this list of conditions and the following disclaimer in the	14	* notice, this list of conditions and the following disclaimer in the
15	* documentation and/or other materials provided with the distribution.	15	* documentation and/or other materials provided with the distribution.
16	* - The name of the author may not be used to endorse or promote products	16	* - The name of the author may not be used to endorse or promote products
17	* derived from this software without specific prior written permission.	17	* derived from this software without specific prior written permission.
18	*	18	*
19	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR	19	* THIS SOFTWARE IS PROVIDED BY THE AUTHOR ``AS IS'' AND ANY EXPRESS OR
20	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES	20	* IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE IMPLIED WARRANTIES
21	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.	21	* OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE ARE DISCLAIMED.
22	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,	22	* IN NO EVENT SHALL THE AUTHOR BE LIABLE FOR ANY DIRECT, INDIRECT,
23	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT	23	* INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL DAMAGES (INCLUDING, BUT
24	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,	24	* NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS OR SERVICES; LOSS OF USE,
25	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY	25	* DATA, OR PROFITS; OR BUSINESS INTERRUPTION) HOWEVER CAUSED AND ON ANY
26	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT	26	* THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT LIABILITY, OR TORT
27	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF	27	* (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY OUT OF THE USE OF
28	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.	28	* THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF SUCH DAMAGE.
29	*/	29	*/
30		30
31	/** @addtogroup generic	31	/** @addtogroup generic
32	* @{	32	* @{
33	*/	33	*/
34		34
35	/**	35	/**
36	* @file	36	* @file
37	* @brief Userspace ELF loader.	37	* @brief Userspace ELF loader.
38	*	38	*
39	* This module allows loading ELF binaries (both executables and	39	* This module allows loading ELF binaries (both executables and
40	* shared objects) from VFS. The current implementation allocates	40	* shared objects) from VFS. The current implementation allocates
41	* anonymous memory, fills it with segment data and then adjusts	41	* anonymous memory, fills it with segment data and then adjusts
42	* the memory areas' flags to the final value. In the future,	42	* the memory areas' flags to the final value. In the future,
43	* the segments will be mapped directly from the file.	43	* the segments will be mapped directly from the file.
44	*/	44	*/
45		45
46	#include <stdio.h>	46	#include <stdio.h>
47	#include <sys/types.h>	47	#include <sys/types.h>
48	#include <align.h>	48	#include <align.h>
49	#include <assert.h>	49	#include <assert.h>
50	#include <as.h>	50	#include <as.h>
51	#include <unistd.h>	51	#include <unistd.h>
52	#include <fcntl.h>	52	#include <fcntl.h>
53	#include <loader/pcb.h>	53	#include <loader/pcb.h>
54		54
55	#include "elf.h"	55	#include "elf.h"
56	#include "arch/pcb.h"	-
57	#include "elf_load.h"	56	#include "elf_load.h"
58	#include "arch.h"	57	#include "arch.h"
59		58
60	static char *error_codes[] = {	59	static char *error_codes[] = {
61	"no error",	60	"no error",
62	"invalid image",	61	"invalid image",
63	"address space error",	62	"address space error",
64	"incompatible image",	63	"incompatible image",
65	"unsupported image type",	64	"unsupported image type",
66	"irrecoverable error"	65	"irrecoverable error"
67	};	66	};
68		67
69	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias);	68	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias);
70	static int segment_header(elf_ld_t elf, elf_segment_header_t entry);	69	static int segment_header(elf_ld_t elf, elf_segment_header_t entry);
71	static int section_header(elf_ld_t elf, elf_section_header_t entry);	70	static int section_header(elf_ld_t elf, elf_section_header_t entry);
72	static int load_segment(elf_ld_t elf, elf_segment_header_t entry);	71	static int load_segment(elf_ld_t elf, elf_segment_header_t entry);
73		72
74	/** Load ELF binary from a file.	73	/** Load ELF binary from a file.
75	*	74	*
76	* Load an ELF binary from the specified file. If the file is	75	* Load an ELF binary from the specified file. If the file is
77	* an executable program, it is loaded unbiased. If it is a shared	76	* an executable program, it is loaded unbiased. If it is a shared
78	* object, it is loaded with the bias @a so_bias. Some information	77	* object, it is loaded with the bias @a so_bias. Some information
79	* extracted from the binary is stored in a elf_info_t structure	78	* extracted from the binary is stored in a elf_info_t structure
80	* pointed to by @a info.	79	* pointed to by @a info.
81	*	80	*
82	* @param file_name Path to the ELF file.	81	* @param file_name Path to the ELF file.
83	* @param so_bias Bias to use if the file is a shared object.	82	* @param so_bias Bias to use if the file is a shared object.
84	* @param info Pointer to a structure for storing information	83	* @param info Pointer to a structure for storing information
85	* extracted from the binary.	84	* extracted from the binary.
86	*	85	*
87	* @return EOK on success or negative error code.	86	* @return EOK on success or negative error code.
88	*/	87	*/
89	int elf_load_file(char file_name, size_t so_bias, elf_info_t info)	88	int elf_load_file(char file_name, size_t so_bias, elf_info_t info)
90	{	89	{
91	elf_ld_t elf;	90	elf_ld_t elf;
92		91
93	int fd;	92	int fd;
94	int rc;	93	int rc;
95		94
96	// printf("open and read '%s'...\n", file_name);	95	// printf("open and read '%s'...\n", file_name);
97		96
98	fd = open(file_name, O_RDONLY);	97	fd = open(file_name, O_RDONLY);
99	if (fd < 0) {	98	if (fd < 0) {
100	printf("failed opening file\n");	99	printf("failed opening file\n");
101	return -1;	100	return -1;
102	}	101	}
103		102
104	elf.fd = fd;	103	elf.fd = fd;
105	elf.info = info;	104	elf.info = info;
106		105
107	rc = elf_load(&elf, so_bias);	106	rc = elf_load(&elf, so_bias);
108		107
109	close(fd);	108	close(fd);
110		109
111	return rc;	110	return rc;
112	}	111	}
113		112
114	/** Run an ELF executable.	113	/** Run an ELF executable.
115	*	114	*
116	* Transfers control to the entry point of an ELF executable loaded	115	* Transfers control to the entry point of an ELF executable loaded
117	* earlier with elf_load_file(). This function does not return.	116	* earlier with elf_load_file(). This function does not return.
118	*	117	*
119	* @param info Info structure filled earlier by elf_load_file()	118	* @param info Info structure filled earlier by elf_load_file()
120	*/	119	*/
121	void elf_run(elf_info_t info, void pcb)	120	void elf_run(elf_info_t info, pcb_t pcb)
122	{	121	{
123	program_run(info->entry, pcb);	122	program_run(info->entry, pcb);
124		123
125	/* not reached */	124	/* not reached */
126	}	125	}
127		126
128	/** Create the program control block (PCB).	127	/** Create the program control block (PCB).
129	*	128	*
130	* Create and install the program control block, initialising it	129	* Fills the program control block @a pcb with information from
131	* with program information from @a info.	130	* @a info.
132	*	131	*
133	* @param info Program info structure	132	* @param info Program info structure
134	* @return EOK on success or negative error code	133	* @return EOK on success or negative error code
135	*/	134	*/
136	int elf_create_pcb(elf_info_t *info)	135	void elf_create_pcb(elf_info_t info, pcb_t pcb)
137	{	136	{
138	pcb_t *pcb;	-
139	void *a;	-
140		-
141	pcb = __pcb_get();	-
142		-
143	a = as_area_create(pcb, sizeof(pcb_t), AS_AREA_READ \| AS_AREA_WRITE);	-
144	if (a == (void *)(-1)) {	-
145	printf("elf_create_pcb: memory mapping failed\n");	-
146	return EE_MEMORY;	-
147	}	-
148		-
149	pcb->entry = info->entry;	137	pcb->entry = info->entry;
150	pcb->dynamic = info->dynamic;	138	pcb->dynamic = info->dynamic;
151		-
152	return 0;	-
153	}	139	}
154		140
155		141
156	/** Load an ELF binary.	142	/** Load an ELF binary.
157	*	143	*
158	* The @a elf structure contains the loader state, including	144	* The @a elf structure contains the loader state, including
159	* an open file, from which the binary will be loaded,	145	* an open file, from which the binary will be loaded,
160	* a pointer to the @c info structure etc.	146	* a pointer to the @c info structure etc.
161	*	147	*
162	* @param elf Pointer to loader state buffer.	148	* @param elf Pointer to loader state buffer.
163	* @param so_bias Bias to use if the file is a shared object.	149	* @param so_bias Bias to use if the file is a shared object.
164	* @return EE_OK on success or EE_xx error code.	150	* @return EE_OK on success or EE_xx error code.
165	*/	151	*/
166	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias)	152	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias)
167	{	153	{
168	elf_header_t header_buf;	154	elf_header_t header_buf;
169	elf_header_t *header = &header_buf;	155	elf_header_t *header = &header_buf;
170	int i, rc;	156	int i, rc;
171		157
172	rc = read(elf->fd, header, sizeof(elf_header_t));	158	rc = read(elf->fd, header, sizeof(elf_header_t));
173	if (rc < 0) {	159	if (rc < 0) {
174	printf("read error\n");	160	printf("read error\n");
175	return EE_INVALID;	161	return EE_INVALID;
176	}	162	}
177		163
178	elf->header = header;	164	elf->header = header;
179		165
180	// printf("ELF-load:");	166	// printf("ELF-load:");
181	/* Identify ELF */	167	/* Identify ELF */
182	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|	168	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|
183	header->e_ident[EI_MAG1] != ELFMAG1 \|\|	169	header->e_ident[EI_MAG1] != ELFMAG1 \|\|
184	header->e_ident[EI_MAG2] != ELFMAG2 \|\|	170	header->e_ident[EI_MAG2] != ELFMAG2 \|\|
185	header->e_ident[EI_MAG3] != ELFMAG3) {	171	header->e_ident[EI_MAG3] != ELFMAG3) {
186	printf("invalid header\n");	172	printf("invalid header\n");
187	return EE_INVALID;	173	return EE_INVALID;
188	}	174	}
189		175
190	/* Identify ELF compatibility */	176	/* Identify ELF compatibility */
191	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|	177	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|
192	header->e_machine != ELF_MACHINE \|\|	178	header->e_machine != ELF_MACHINE \|\|
193	header->e_ident[EI_VERSION] != EV_CURRENT \|\|	179	header->e_ident[EI_VERSION] != EV_CURRENT \|\|
194	header->e_version != EV_CURRENT \|\|	180	header->e_version != EV_CURRENT \|\|
195	header->e_ident[EI_CLASS] != ELF_CLASS) {	181	header->e_ident[EI_CLASS] != ELF_CLASS) {
196	printf("incompatible data/version/class\n");	182	printf("incompatible data/version/class\n");
197	return EE_INCOMPATIBLE;	183	return EE_INCOMPATIBLE;
198	}	184	}
199		185
200	if (header->e_phentsize != sizeof(elf_segment_header_t)) {	186	if (header->e_phentsize != sizeof(elf_segment_header_t)) {
201	printf("e_phentsize:%d != %d\n", header->e_phentsize,	187	printf("e_phentsize:%d != %d\n", header->e_phentsize,
202	sizeof(elf_segment_header_t));	188	sizeof(elf_segment_header_t));
203	return EE_INCOMPATIBLE;	189	return EE_INCOMPATIBLE;
204	}	190	}
205		191
206	if (header->e_shentsize != sizeof(elf_section_header_t)) {	192	if (header->e_shentsize != sizeof(elf_section_header_t)) {
207	printf("e_shentsize:%d != %d\n", header->e_shentsize,	193	printf("e_shentsize:%d != %d\n", header->e_shentsize,
208	sizeof(elf_section_header_t));	194	sizeof(elf_section_header_t));
209	return EE_INCOMPATIBLE;	195	return EE_INCOMPATIBLE;
210	}	196	}
211		197
212	/* Check if the object type is supported. */	198	/* Check if the object type is supported. */
213	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {	199	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {
214	printf("Object type %d is not supported\n", header->e_type);	200	printf("Object type %d is not supported\n", header->e_type);
215	return EE_UNSUPPORTED;	201	return EE_UNSUPPORTED;
216	}	202	}
217		203
218	/* Shared objects can be loaded with a bias */	204	/* Shared objects can be loaded with a bias */
219	// printf("Object type: %d\n", header->e_type);	205	// printf("Object type: %d\n", header->e_type);
220	if (header->e_type == ET_DYN)	206	if (header->e_type == ET_DYN)
221	elf->bias = so_bias;	207	elf->bias = so_bias;
222	else	208	else
223	elf->bias = 0;	209	elf->bias = 0;
224		210
225	// printf("Bias set to 0x%x\n", elf->bias);	211	// printf("Bias set to 0x%x\n", elf->bias);
226	elf->info->interp = NULL;	212	elf->info->interp = NULL;
227	elf->info->dynamic = NULL;	213	elf->info->dynamic = NULL;
228		214
229	// printf("parse segments\n");	215	// printf("parse segments\n");
230		216
231	/* Walk through all segment headers and process them. */	217	/* Walk through all segment headers and process them. */
232	for (i = 0; i < header->e_phnum; i++) {	218	for (i = 0; i < header->e_phnum; i++) {
233	elf_segment_header_t segment_hdr;	219	elf_segment_header_t segment_hdr;
234		220
235	/* Seek to start of segment header */	221	/* Seek to start of segment header */
236	lseek(elf->fd, header->e_phoff	222	lseek(elf->fd, header->e_phoff
237	+ i * sizeof(elf_segment_header_t), SEEK_SET);	223	+ i * sizeof(elf_segment_header_t), SEEK_SET);
238		224
239	rc = read(elf->fd, &segment_hdr, sizeof(elf_segment_header_t));	225	rc = read(elf->fd, &segment_hdr, sizeof(elf_segment_header_t));
240	if (rc < 0) { printf("read error\n"); return EE_INVALID; }	226	if (rc < 0) { printf("read error\n"); return EE_INVALID; }
241		227
242	rc = segment_header(elf, &segment_hdr);	228	rc = segment_header(elf, &segment_hdr);
243	if (rc != EE_OK)	229	if (rc != EE_OK)
244	return rc;	230	return rc;
245	}	231	}
246		232
247	// printf("parse sections\n");	233	// printf("parse sections\n");
248		234
249	/* Inspect all section headers and proccess them. */	235	/* Inspect all section headers and proccess them. */
250	for (i = 0; i < header->e_shnum; i++) {	236	for (i = 0; i < header->e_shnum; i++) {
251	elf_section_header_t section_hdr;	237	elf_section_header_t section_hdr;
252		238
253	/* Seek to start of section header */	239	/* Seek to start of section header */
254	lseek(elf->fd, header->e_shoff	240	lseek(elf->fd, header->e_shoff
255	+ i * sizeof(elf_section_header_t), SEEK_SET);	241	+ i * sizeof(elf_section_header_t), SEEK_SET);
256		242
257	rc = read(elf->fd, &section_hdr, sizeof(elf_section_header_t));	243	rc = read(elf->fd, &section_hdr, sizeof(elf_section_header_t));
258	if (rc < 0) { printf("read error\n"); return EE_INVALID; }	244	if (rc < 0) { printf("read error\n"); return EE_INVALID; }
259		245
260	rc = section_header(elf, &section_hdr);	246	rc = section_header(elf, &section_hdr);
261	if (rc != EE_OK)	247	if (rc != EE_OK)
262	return rc;	248	return rc;
263	}	249	}
264		250
265	elf->info->entry =	251	elf->info->entry =
266	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);	252	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);
267		253
268	// printf("done\n");	254	// printf("done\n");
269		255
270	return EE_OK;	256	return EE_OK;
271	}	257	}
272		258
273	/** Print error message according to error code.	259	/** Print error message according to error code.
274	*	260	*
275	* @param rc Return code returned by elf_load().	261	* @param rc Return code returned by elf_load().
276	*	262	*
277	* @return NULL terminated description of error.	263	* @return NULL terminated description of error.
278	*/	264	*/
279	char *elf_error(unsigned int rc)	265	char *elf_error(unsigned int rc)
280	{	266	{
281	assert(rc < sizeof(error_codes) / sizeof(char *));	267	assert(rc < sizeof(error_codes) / sizeof(char *));
282		268
283	return error_codes[rc];	269	return error_codes[rc];
284	}	270	}
285		271
286	/** Process segment header.	272	/** Process segment header.
287	*	273	*
288	* @param entry Segment header.	274	* @param entry Segment header.
289	*	275	*
290	* @return EE_OK on success, error code otherwise.	276	* @return EE_OK on success, error code otherwise.
291	*/	277	*/
292	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)	278	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)
293	{	279	{
294	switch (entry->p_type) {	280	switch (entry->p_type) {
295	case PT_NULL:	281	case PT_NULL:
296	case PT_PHDR:	282	case PT_PHDR:
297	break;	283	break;
298	case PT_LOAD:	284	case PT_LOAD:
299	return load_segment(elf, entry);	285	return load_segment(elf, entry);
300	break;	286	break;
301	case PT_INTERP:	287	case PT_INTERP:
302	/* Assume silently interp == "/rtld.so" */	288	/* Assume silently interp == "/rtld.so" */
303	elf->info->interp = "/rtld.so";	289	elf->info->interp = "/rtld.so";
304	break;	290	break;
305	case PT_DYNAMIC:	291	case PT_DYNAMIC:
306	case PT_SHLIB:	292	case PT_SHLIB:
307	case PT_NOTE:	293	case PT_NOTE:
308	case PT_LOPROC:	294	case PT_LOPROC:
309	case PT_HIPROC:	295	case PT_HIPROC:
310	default:	296	default:
311	printf("segment p_type %d unknown\n", entry->p_type);	297	printf("segment p_type %d unknown\n", entry->p_type);
312	return EE_UNSUPPORTED;	298	return EE_UNSUPPORTED;
313	break;	299	break;
314	}	300	}
315	return EE_OK;	301	return EE_OK;
316	}	302	}
317		303
318	/** Load segment described by program header entry.	304	/** Load segment described by program header entry.
319	*	305	*
320	* @param elf Loader state.	306	* @param elf Loader state.
321	* @param entry Program header entry describing segment to be loaded.	307	* @param entry Program header entry describing segment to be loaded.
322	*	308	*
323	* @return EE_OK on success, error code otherwise.	309	* @return EE_OK on success, error code otherwise.
324	*/	310	*/
325	int load_segment(elf_ld_t elf, elf_segment_header_t entry)	311	int load_segment(elf_ld_t elf, elf_segment_header_t entry)
326	{	312	{
327	void *a;	313	void *a;
328	int flags = 0;	314	int flags = 0;
329	uintptr_t bias;	315	uintptr_t bias;
330	uintptr_t base;	316	uintptr_t base;
331	size_t mem_sz;	317	size_t mem_sz;
332	int rc;	318	int rc;
333		319
334	// printf("load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,	320	// printf("load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,
335	// entry->p_memsz);	321	// entry->p_memsz);
336		322
337	bias = elf->bias;	323	bias = elf->bias;
338		324
339	if (entry->p_align > 1) {	325	if (entry->p_align > 1) {
340	if ((entry->p_offset % entry->p_align) !=	326	if ((entry->p_offset % entry->p_align) !=
341	(entry->p_vaddr % entry->p_align)) {	327	(entry->p_vaddr % entry->p_align)) {
342	printf("align check 1 failed offset%%align=%d, vaddr%%align=%d\n",	328	printf("align check 1 failed offset%%align=%d, vaddr%%align=%d\n",
343	entry->p_offset % entry->p_align,	329	entry->p_offset % entry->p_align,
344	entry->p_vaddr % entry->p_align	330	entry->p_vaddr % entry->p_align
345	);	331	);
346	return EE_INVALID;	332	return EE_INVALID;
347	}	333	}
348	}	334	}
349		335
350	/* Final flags that will be set for the memory area */	336	/* Final flags that will be set for the memory area */
351		337
352	if (entry->p_flags & PF_X)	338	if (entry->p_flags & PF_X)
353	flags \|= AS_AREA_EXEC;	339	flags \|= AS_AREA_EXEC;
354	if (entry->p_flags & PF_W)	340	if (entry->p_flags & PF_W)
355	flags \|= AS_AREA_WRITE;	341	flags \|= AS_AREA_WRITE;
356	if (entry->p_flags & PF_R)	342	if (entry->p_flags & PF_R)
357	flags \|= AS_AREA_READ;	343	flags \|= AS_AREA_READ;
358	flags \|= AS_AREA_CACHEABLE;	344	flags \|= AS_AREA_CACHEABLE;
359		345
360	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);	346	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);
361	mem_sz = entry->p_memsz + (entry->p_vaddr - base);	347	mem_sz = entry->p_memsz + (entry->p_vaddr - base);
362		348
363	// printf("map to p_vaddr=0x%x-0x%x...\n", entry->p_vaddr + bias,	349	// printf("map to p_vaddr=0x%x-0x%x...\n", entry->p_vaddr + bias,
364	// entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));	350	// entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));
365		351
366	/*	352	/*
367	* For the course of loading, the area needs to be readable	353	* For the course of loading, the area needs to be readable
368	* and writeable.	354	* and writeable.
369	*/	355	*/
370	a = as_area_create((uint8_t *)base + bias,	356	a = as_area_create((uint8_t *)base + bias,
371	mem_sz, AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);	357	mem_sz, AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);
372	if (a == (void *)(-1)) {	358	if (a == (void *)(-1)) {
373	printf("memory mapping failed\n");	359	printf("memory mapping failed\n");
374	return EE_MEMORY;	360	return EE_MEMORY;
375	}	361	}
376		362
377	// printf("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",	363	// printf("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",
378	// entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);	364	// entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);
379		365
380	/*	366	/*
381	* Load segment data	367	* Load segment data
382	*/	368	*/
383	// printf("seek to %d\n", entry->p_offset);	369	// printf("seek to %d\n", entry->p_offset);
384	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);	370	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);
385	if (rc < 0) { printf("seek error\n"); return EE_INVALID; }	371	if (rc < 0) { printf("seek error\n"); return EE_INVALID; }
386		372
387	// printf("read 0x%x bytes to address 0x%x\n", entry->p_filesz, entry->p_vaddr+bias);	373	// printf("read 0x%x bytes to address 0x%x\n", entry->p_filesz, entry->p_vaddr+bias);
388	/* rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);	374	/* rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);
389	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/	375	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/
390		376
391	/* Long reads are not possible yet. Load segment picewise */	377	/* Long reads are not possible yet. Load segment picewise */
392		378
393	unsigned left, now;	379	unsigned left, now;
394	uint8_t *dp;	380	uint8_t *dp;
395		381
396	left = entry->p_filesz;	382	left = entry->p_filesz;
397	dp = (uint8_t *)(entry->p_vaddr + bias);	383	dp = (uint8_t *)(entry->p_vaddr + bias);
398		384
399	while (left > 0) {	385	while (left > 0) {
400	now = 16384;	386	now = 16384;
401	if (now > left) now = left;	387	if (now > left) now = left;
402		388
403	// printf("read %d...", now);	389	// printf("read %d...", now);
404	rc = read(elf->fd, dp, now);	390	rc = read(elf->fd, dp, now);
405	// printf("->%d\n", rc);	391	// printf("->%d\n", rc);
406		392
407	if (rc < 0) { printf("read error\n"); return EE_INVALID; }	393	if (rc < 0) { printf("read error\n"); return EE_INVALID; }
408		394
409	left -= now;	395	left -= now;
410	dp += now;	396	dp += now;
411	}	397	}
412		398
413	// printf("set area flags to %d\n", flags);	399	// printf("set area flags to %d\n", flags);
414	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);	400	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);
415	if (rc != 0) {	401	if (rc != 0) {
416	printf("failed to set memory area flags\n");	402	printf("failed to set memory area flags\n");
417	return EE_MEMORY;	403	return EE_MEMORY;
418	}	404	}
419		405
420	return EE_OK;	406	return EE_OK;
421	}	407	}
422		408
423	/** Process section header.	409	/** Process section header.
424	*	410	*
425	* @param elf Loader state.	411	* @param elf Loader state.
426	* @param entry Segment header.	412	* @param entry Segment header.
427	*	413	*
428	* @return EE_OK on success, error code otherwise.	414	* @return EE_OK on success, error code otherwise.
429	*/	415	*/
430	static int section_header(elf_ld_t elf, elf_section_header_t entry)	416	static int section_header(elf_ld_t elf, elf_section_header_t entry)
431	{	417	{
432	switch (entry->sh_type) {	418	switch (entry->sh_type) {
433	case SHT_PROGBITS:	419	case SHT_PROGBITS:
434	if (entry->sh_flags & SHF_TLS) {	420	if (entry->sh_flags & SHF_TLS) {
435	/* .tdata */	421	/* .tdata */
436	}	422	}
437	break;	423	break;
438	case SHT_NOBITS:	424	case SHT_NOBITS:
439	if (entry->sh_flags & SHF_TLS) {	425	if (entry->sh_flags & SHF_TLS) {
440	/* .tbss */	426	/* .tbss */
441	}	427	}
442	break;	428	break;
443	case SHT_DYNAMIC:	429	case SHT_DYNAMIC:
444	/* Record pointer to dynamic section into info structure */	430	/* Record pointer to dynamic section into info structure */
445	elf->info->dynamic =	431	elf->info->dynamic =
446	(void )((uint8_t )entry->sh_addr + elf->bias);	432	(void )((uint8_t )entry->sh_addr + elf->bias);
447	printf("dynamic section found at 0x%x\n",	433	printf("dynamic section found at 0x%x\n",
448	(uintptr_t)elf->info->dynamic);	434	(uintptr_t)elf->info->dynamic);
449	break;	435	break;
450	default:	436	default:
451	break;	437	break;
452	}	438	}
453		439
454	return EE_OK;	440	return EE_OK;
455	}	441	}
456		442
457	/** @}	443	/** @}
458	*/	444	*/
459		445

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(root)/branches/dynload/uspace/srv/loader/elf_load.c – Rev 3169 → 3170