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 <smc.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);
 
/** Read until the buffer is read in its entirety. */
static int my_read(int fd, char *buf, size_t len)
{
    int cnt = 0;
    do {
        buf += cnt;
        len -= cnt;
        cnt = read(fd, buf, len);
    } while ((cnt > 0) && ((len - cnt) > 0));
 
    return cnt;
}
 
/** 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, eld_flags_t flags,
    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 (error %d)\n", fd);
        return -1;
    }
 
    elf.fd = fd;
    elf.info = info;
    elf.flags = flags;
 
    rc = elf_load(&elf, so_bias);
 
    close(fd);
 
    return rc;
}
 
/** 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;
    pcb->rtld_runtime = NULL;
}
 
 
/** 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 = my_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 = my_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 = my_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 == "/app/dload" */
        elf->info->interp = "/app/dload";
        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 = my_read(elf->fd, dp, now);
//      printf("->%d\n", rc);
 
        if (rc < 0) {
            printf("read error\n");
            return EE_INVALID;
        }
 
        left -= now;
        dp += now;
    }
 
    /*
     * The caller wants to modify the segments first. He will then
     * need to set the right access mode and ensure SMC coherence.
     */
    if ((elf->flags & ELDF_RW) != 0) return EE_OK;
 
//  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;
    }
 
    if (flags & AS_AREA_EXEC) {
        /* Enforce SMC coherence for the segment */
        if (smc_coherence(entry->p_vaddr + bias, entry->p_filesz))
            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 3681	Rev 3686
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 <smc.h>	53	#include <smc.h>
54	#include <loader/pcb.h>	54	#include <loader/pcb.h>
55		55
56	#include "elf.h"	56	#include "elf.h"
57	#include "elf_load.h"	57	#include "elf_load.h"
58	#include "arch.h"	58	#include "arch.h"
59		59
60	static char *error_codes[] = {	60	static char *error_codes[] = {
61	"no error",	61	"no error",
62	"invalid image",	62	"invalid image",
63	"address space error",	63	"address space error",
64	"incompatible image",	64	"incompatible image",
65	"unsupported image type",	65	"unsupported image type",
66	"irrecoverable error"	66	"irrecoverable error"
67	};	67	};
68		68
69	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias);	69	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);	70	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);	71	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);	72	static int load_segment(elf_ld_t elf, elf_segment_header_t entry);
73		73
74	/** Read until the buffer is read in its entirety. */	74	/** Read until the buffer is read in its entirety. */
75	static int my_read(int fd, char *buf, size_t len)	75	static int my_read(int fd, char *buf, size_t len)
76	{	76	{
77	int cnt = 0;	77	int cnt = 0;
78	do {	78	do {
79	buf += cnt;	79	buf += cnt;
80	len -= cnt;	80	len -= cnt;
81	cnt = read(fd, buf, len);	81	cnt = read(fd, buf, len);
82	} while ((cnt > 0) && ((len - cnt) > 0));	82	} while ((cnt > 0) && ((len - cnt) > 0));
83		83
84	return cnt;	84	return cnt;
85	}	85	}
86		86
87	/** Load ELF binary from a file.	87	/** Load ELF binary from a file.
88	*	88	*
89	* Load an ELF binary from the specified file. If the file is	89	* Load an ELF binary from the specified file. If the file is
90	* an executable program, it is loaded unbiased. If it is a shared	90	* an executable program, it is loaded unbiased. If it is a shared
91	* object, it is loaded with the bias @a so_bias. Some information	91	* object, it is loaded with the bias @a so_bias. Some information
92	* extracted from the binary is stored in a elf_info_t structure	92	* extracted from the binary is stored in a elf_info_t structure
93	* pointed to by @a info.	93	* pointed to by @a info.
94	*	94	*
95	* @param file_name Path to the ELF file.	95	* @param file_name Path to the ELF file.
96	* @param so_bias Bias to use if the file is a shared object.	96	* @param so_bias Bias to use if the file is a shared object.
97	* @param info Pointer to a structure for storing information	97	* @param info Pointer to a structure for storing information
98	* extracted from the binary.	98	* extracted from the binary.
99	*	99	*
100	* @return EOK on success or negative error code.	100	* @return EOK on success or negative error code.
101	*/	101	*/
102	int elf_load_file(char *file_name, size_t so_bias, eld_flags_t flags,	102	int elf_load_file(char *file_name, size_t so_bias, eld_flags_t flags,
103	elf_info_t *info)	103	elf_info_t *info)
104	{	104	{
105	elf_ld_t elf;	105	elf_ld_t elf;
106		106
107	int fd;	107	int fd;
108	int rc;	108	int rc;
109		109
110	// printf("open and read '%s'...\n", file_name);	110	// printf("open and read '%s'...\n", file_name);
111		111
112	fd = open(file_name, O_RDONLY);	112	fd = open(file_name, O_RDONLY);
113	if (fd < 0) {	113	if (fd < 0) {
114	printf("failed opening file (error %d)\n", fd);	114	printf("failed opening file (error %d)\n", fd);
115	return -1;	115	return -1;
116	}	116	}
117		117
118	elf.fd = fd;	118	elf.fd = fd;
119	elf.info = info;	119	elf.info = info;
120	elf.flags = flags;	120	elf.flags = flags;
121		121
122	rc = elf_load(&elf, so_bias);	122	rc = elf_load(&elf, so_bias);
123		123
124	close(fd);	124	close(fd);
125		125
126	return rc;	126	return rc;
127	}	127	}
128		128
129	/** Create the program control block (PCB).	129	/** Create the program control block (PCB).
130	*	130	*
131	* Fills the program control block @a pcb with information from	131	* Fills the program control block @a pcb with information from
132	* @a info.	132	* @a info.
133	*	133	*
134	* @param info Program info structure	134	* @param info Program info structure
135	* @return EOK on success or negative error code	135	* @return EOK on success or negative error code
136	*/	136	*/
137	void elf_create_pcb(elf_info_t info, pcb_t pcb)	137	void elf_create_pcb(elf_info_t info, pcb_t pcb)
138	{	138	{
139	pcb->entry = info->entry;	139	pcb->entry = info->entry;
140	pcb->dynamic = info->dynamic;	140	pcb->dynamic = info->dynamic;
-		141	pcb->rtld_runtime = NULL;
141	}	142	}
142		143
143		144
144	/** Load an ELF binary.	145	/** Load an ELF binary.
145	*	146	*
146	* The @a elf structure contains the loader state, including	147	* The @a elf structure contains the loader state, including
147	* an open file, from which the binary will be loaded,	148	* an open file, from which the binary will be loaded,
148	* a pointer to the @c info structure etc.	149	* a pointer to the @c info structure etc.
149	*	150	*
150	* @param elf Pointer to loader state buffer.	151	* @param elf Pointer to loader state buffer.
151	* @param so_bias Bias to use if the file is a shared object.	152	* @param so_bias Bias to use if the file is a shared object.
152	* @return EE_OK on success or EE_xx error code.	153	* @return EE_OK on success or EE_xx error code.
153	*/	154	*/
154	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias)	155	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias)
155	{	156	{
156	elf_header_t header_buf;	157	elf_header_t header_buf;
157	elf_header_t *header = &header_buf;	158	elf_header_t *header = &header_buf;
158	int i, rc;	159	int i, rc;
159		160
160	rc = my_read(elf->fd, header, sizeof(elf_header_t));	161	rc = my_read(elf->fd, header, sizeof(elf_header_t));
161	if (rc < 0) {	162	if (rc < 0) {
162	printf("read error\n");	163	printf("read error\n");
163	return EE_INVALID;	164	return EE_INVALID;
164	}	165	}
165		166
166	elf->header = header;	167	elf->header = header;
167		168
168	// printf("ELF-load:");	169	// printf("ELF-load:");
169	/* Identify ELF */	170	/* Identify ELF */
170	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|	171	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|
171	header->e_ident[EI_MAG1] != ELFMAG1 \|\|	172	header->e_ident[EI_MAG1] != ELFMAG1 \|\|
172	header->e_ident[EI_MAG2] != ELFMAG2 \|\|	173	header->e_ident[EI_MAG2] != ELFMAG2 \|\|
173	header->e_ident[EI_MAG3] != ELFMAG3) {	174	header->e_ident[EI_MAG3] != ELFMAG3) {
174	printf("invalid header\n");	175	printf("invalid header\n");
175	return EE_INVALID;	176	return EE_INVALID;
176	}	177	}
177		178
178	/* Identify ELF compatibility */	179	/* Identify ELF compatibility */
179	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|	180	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|
180	header->e_machine != ELF_MACHINE \|\|	181	header->e_machine != ELF_MACHINE \|\|
181	header->e_ident[EI_VERSION] != EV_CURRENT \|\|	182	header->e_ident[EI_VERSION] != EV_CURRENT \|\|
182	header->e_version != EV_CURRENT \|\|	183	header->e_version != EV_CURRENT \|\|
183	header->e_ident[EI_CLASS] != ELF_CLASS) {	184	header->e_ident[EI_CLASS] != ELF_CLASS) {
184	printf("incompatible data/version/class\n");	185	printf("incompatible data/version/class\n");
185	return EE_INCOMPATIBLE;	186	return EE_INCOMPATIBLE;
186	}	187	}
187		188
188	if (header->e_phentsize != sizeof(elf_segment_header_t)) {	189	if (header->e_phentsize != sizeof(elf_segment_header_t)) {
189	printf("e_phentsize:%d != %d\n", header->e_phentsize,	190	printf("e_phentsize:%d != %d\n", header->e_phentsize,
190	sizeof(elf_segment_header_t));	191	sizeof(elf_segment_header_t));
191	return EE_INCOMPATIBLE;	192	return EE_INCOMPATIBLE;
192	}	193	}
193		194
194	if (header->e_shentsize != sizeof(elf_section_header_t)) {	195	if (header->e_shentsize != sizeof(elf_section_header_t)) {
195	printf("e_shentsize:%d != %d\n", header->e_shentsize,	196	printf("e_shentsize:%d != %d\n", header->e_shentsize,
196	sizeof(elf_section_header_t));	197	sizeof(elf_section_header_t));
197	return EE_INCOMPATIBLE;	198	return EE_INCOMPATIBLE;
198	}	199	}
199		200
200	/* Check if the object type is supported. */	201	/* Check if the object type is supported. */
201	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {	202	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {
202	printf("Object type %d is not supported\n", header->e_type);	203	printf("Object type %d is not supported\n", header->e_type);
203	return EE_UNSUPPORTED;	204	return EE_UNSUPPORTED;
204	}	205	}
205		206
206	/* Shared objects can be loaded with a bias */	207	/* Shared objects can be loaded with a bias */
207	// printf("Object type: %d\n", header->e_type);	208	// printf("Object type: %d\n", header->e_type);
208	if (header->e_type == ET_DYN)	209	if (header->e_type == ET_DYN)
209	elf->bias = so_bias;	210	elf->bias = so_bias;
210	else	211	else
211	elf->bias = 0;	212	elf->bias = 0;
212		213
213	// printf("Bias set to 0x%x\n", elf->bias);	214	// printf("Bias set to 0x%x\n", elf->bias);
214	elf->info->interp = NULL;	215	elf->info->interp = NULL;
215	elf->info->dynamic = NULL;	216	elf->info->dynamic = NULL;
216		217
217	// printf("parse segments\n");	218	// printf("parse segments\n");
218		219
219	/* Walk through all segment headers and process them. */	220	/* Walk through all segment headers and process them. */
220	for (i = 0; i < header->e_phnum; i++) {	221	for (i = 0; i < header->e_phnum; i++) {
221	elf_segment_header_t segment_hdr;	222	elf_segment_header_t segment_hdr;
222		223
223	/* Seek to start of segment header */	224	/* Seek to start of segment header */
224	lseek(elf->fd, header->e_phoff	225	lseek(elf->fd, header->e_phoff
225	+ i * sizeof(elf_segment_header_t), SEEK_SET);	226	+ i * sizeof(elf_segment_header_t), SEEK_SET);
226		227
227	rc = my_read(elf->fd, &segment_hdr,	228	rc = my_read(elf->fd, &segment_hdr,
228	sizeof(elf_segment_header_t));	229	sizeof(elf_segment_header_t));
229	if (rc < 0) {	230	if (rc < 0) {
230	printf("read error\n");	231	printf("read error\n");
231	return EE_INVALID;	232	return EE_INVALID;
232	}	233	}
233		234
234	rc = segment_header(elf, &segment_hdr);	235	rc = segment_header(elf, &segment_hdr);
235	if (rc != EE_OK)	236	if (rc != EE_OK)
236	return rc;	237	return rc;
237	}	238	}
238		239
239	// printf("parse sections\n");	240	// printf("parse sections\n");
240		241
241	/* Inspect all section headers and proccess them. */	242	/* Inspect all section headers and proccess them. */
242	for (i = 0; i < header->e_shnum; i++) {	243	for (i = 0; i < header->e_shnum; i++) {
243	elf_section_header_t section_hdr;	244	elf_section_header_t section_hdr;
244		245
245	/* Seek to start of section header */	246	/* Seek to start of section header */
246	lseek(elf->fd, header->e_shoff	247	lseek(elf->fd, header->e_shoff
247	+ i * sizeof(elf_section_header_t), SEEK_SET);	248	+ i * sizeof(elf_section_header_t), SEEK_SET);
248		249
249	rc = my_read(elf->fd, &section_hdr,	250	rc = my_read(elf->fd, &section_hdr,
250	sizeof(elf_section_header_t));	251	sizeof(elf_section_header_t));
251	if (rc < 0) {	252	if (rc < 0) {
252	printf("read error\n");	253	printf("read error\n");
253	return EE_INVALID;	254	return EE_INVALID;
254	}	255	}
255		256
256	rc = section_header(elf, &section_hdr);	257	rc = section_header(elf, &section_hdr);
257	if (rc != EE_OK)	258	if (rc != EE_OK)
258	return rc;	259	return rc;
259	}	260	}
260		261
261	elf->info->entry =	262	elf->info->entry =
262	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);	263	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);
263		264
264	// printf("done\n");	265	// printf("done\n");
265		266
266	return EE_OK;	267	return EE_OK;
267	}	268	}
268		269
269	/** Print error message according to error code.	270	/** Print error message according to error code.
270	*	271	*
271	* @param rc Return code returned by elf_load().	272	* @param rc Return code returned by elf_load().
272	*	273	*
273	* @return NULL terminated description of error.	274	* @return NULL terminated description of error.
274	*/	275	*/
275	char *elf_error(unsigned int rc)	276	char *elf_error(unsigned int rc)
276	{	277	{
277	assert(rc < sizeof(error_codes) / sizeof(char *));	278	assert(rc < sizeof(error_codes) / sizeof(char *));
278		279
279	return error_codes[rc];	280	return error_codes[rc];
280	}	281	}
281		282
282	/** Process segment header.	283	/** Process segment header.
283	*	284	*
284	* @param entry Segment header.	285	* @param entry Segment header.
285	*	286	*
286	* @return EE_OK on success, error code otherwise.	287	* @return EE_OK on success, error code otherwise.
287	*/	288	*/
288	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)	289	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)
289	{	290	{
290	switch (entry->p_type) {	291	switch (entry->p_type) {
291	case PT_NULL:	292	case PT_NULL:
292	case PT_PHDR:	293	case PT_PHDR:
293	break;	294	break;
294	case PT_LOAD:	295	case PT_LOAD:
295	return load_segment(elf, entry);	296	return load_segment(elf, entry);
296	break;	297	break;
297	case PT_INTERP:	298	case PT_INTERP:
298	/* Assume silently interp == "/app/dload" */	299	/* Assume silently interp == "/app/dload" */
299	elf->info->interp = "/app/dload";	300	elf->info->interp = "/app/dload";
300	break;	301	break;
301	case PT_DYNAMIC:	302	case PT_DYNAMIC:
302	case PT_SHLIB:	303	case PT_SHLIB:
303	case PT_NOTE:	304	case PT_NOTE:
304	case PT_LOPROC:	305	case PT_LOPROC:
305	case PT_HIPROC:	306	case PT_HIPROC:
306	default:	307	default:
307	printf("segment p_type %d unknown\n", entry->p_type);	308	printf("segment p_type %d unknown\n", entry->p_type);
308	return EE_UNSUPPORTED;	309	return EE_UNSUPPORTED;
309	break;	310	break;
310	}	311	}
311	return EE_OK;	312	return EE_OK;
312	}	313	}
313		314
314	/** Load segment described by program header entry.	315	/** Load segment described by program header entry.
315	*	316	*
316	* @param elf Loader state.	317	* @param elf Loader state.
317	* @param entry Program header entry describing segment to be loaded.	318	* @param entry Program header entry describing segment to be loaded.
318	*	319	*
319	* @return EE_OK on success, error code otherwise.	320	* @return EE_OK on success, error code otherwise.
320	*/	321	*/
321	int load_segment(elf_ld_t elf, elf_segment_header_t entry)	322	int load_segment(elf_ld_t elf, elf_segment_header_t entry)
322	{	323	{
323	void *a;	324	void *a;
324	int flags = 0;	325	int flags = 0;
325	uintptr_t bias;	326	uintptr_t bias;
326	uintptr_t base;	327	uintptr_t base;
327	size_t mem_sz;	328	size_t mem_sz;
328	int rc;	329	int rc;
329		330
330	// printf("load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,	331	// printf("load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,
331	// entry->p_memsz);	332	// entry->p_memsz);
332		333
333	bias = elf->bias;	334	bias = elf->bias;
334		335
335	if (entry->p_align > 1) {	336	if (entry->p_align > 1) {
336	if ((entry->p_offset % entry->p_align) !=	337	if ((entry->p_offset % entry->p_align) !=
337	(entry->p_vaddr % entry->p_align)) {	338	(entry->p_vaddr % entry->p_align)) {
338	printf("align check 1 failed offset%%align=%d, "	339	printf("align check 1 failed offset%%align=%d, "
339	"vaddr%%align=%d\n",	340	"vaddr%%align=%d\n",
340	entry->p_offset % entry->p_align,	341	entry->p_offset % entry->p_align,
341	entry->p_vaddr % entry->p_align	342	entry->p_vaddr % entry->p_align
342	);	343	);
343	return EE_INVALID;	344	return EE_INVALID;
344	}	345	}
345	}	346	}
346		347
347	/* Final flags that will be set for the memory area */	348	/* Final flags that will be set for the memory area */
348		349
349	if (entry->p_flags & PF_X)	350	if (entry->p_flags & PF_X)
350	flags \|= AS_AREA_EXEC;	351	flags \|= AS_AREA_EXEC;
351	if (entry->p_flags & PF_W)	352	if (entry->p_flags & PF_W)
352	flags \|= AS_AREA_WRITE;	353	flags \|= AS_AREA_WRITE;
353	if (entry->p_flags & PF_R)	354	if (entry->p_flags & PF_R)
354	flags \|= AS_AREA_READ;	355	flags \|= AS_AREA_READ;
355	flags \|= AS_AREA_CACHEABLE;	356	flags \|= AS_AREA_CACHEABLE;
356		357
357	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);	358	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);
358	mem_sz = entry->p_memsz + (entry->p_vaddr - base);	359	mem_sz = entry->p_memsz + (entry->p_vaddr - base);
359		360
360	// printf("map to p_vaddr=0x%x-0x%x...\n", entry->p_vaddr + bias,	361	// printf("map to p_vaddr=0x%x-0x%x...\n", entry->p_vaddr + bias,
361	// entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));	362	// entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));
362		363
363	/*	364	/*
364	* For the course of loading, the area needs to be readable	365	* For the course of loading, the area needs to be readable
365	* and writeable.	366	* and writeable.
366	*/	367	*/
367	a = as_area_create((uint8_t *)base + bias, mem_sz,	368	a = as_area_create((uint8_t *)base + bias, mem_sz,
368	AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);	369	AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);
369	if (a == (void *)(-1)) {	370	if (a == (void *)(-1)) {
370	printf("memory mapping failed\n");	371	printf("memory mapping failed\n");
371	return EE_MEMORY;	372	return EE_MEMORY;
372	}	373	}
373		374
374	// printf("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",	375	// printf("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",
375	// entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);	376	// entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);
376		377
377	/*	378	/*
378	* Load segment data	379	* Load segment data
379	*/	380	*/
380	// printf("seek to %d\n", entry->p_offset);	381	// printf("seek to %d\n", entry->p_offset);
381	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);	382	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);
382	if (rc < 0) {	383	if (rc < 0) {
383	printf("seek error\n");	384	printf("seek error\n");
384	return EE_INVALID;	385	return EE_INVALID;
385	}	386	}
386		387
387	// printf("read 0x%x bytes to address 0x%x\n", entry->p_filesz, entry->p_vaddr+bias);	388	// 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);	389	/* rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);
389	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/	390	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/
390		391
391	/* Long reads are not possible yet. Load segment picewise */	392	/* Long reads are not possible yet. Load segment picewise */
392		393
393	unsigned left, now;	394	unsigned left, now;
394	uint8_t *dp;	395	uint8_t *dp;
395		396
396	left = entry->p_filesz;	397	left = entry->p_filesz;
397	dp = (uint8_t *)(entry->p_vaddr + bias);	398	dp = (uint8_t *)(entry->p_vaddr + bias);
398		399
399	while (left > 0) {	400	while (left > 0) {
400	now = 16384;	401	now = 16384;
401	if (now > left) now = left;	402	if (now > left) now = left;
402		403
403	// printf("read %d...", now);	404	// printf("read %d...", now);
404	rc = my_read(elf->fd, dp, now);	405	rc = my_read(elf->fd, dp, now);
405	// printf("->%d\n", rc);	406	// printf("->%d\n", rc);
406		407
407	if (rc < 0) {	408	if (rc < 0) {
408	printf("read error\n");	409	printf("read error\n");
409	return EE_INVALID;	410	return EE_INVALID;
410	}	411	}
411		412
412	left -= now;	413	left -= now;
413	dp += now;	414	dp += now;
414	}	415	}
415		416
416	/*	417	/*
417	* The caller wants to modify the segments first. He will then	418	* The caller wants to modify the segments first. He will then
418	* need to set the right access mode and ensure SMC coherence.	419	* need to set the right access mode and ensure SMC coherence.
419	*/	420	*/
420	if ((elf->flags & ELDF_RW) != 0) return EE_OK;	421	if ((elf->flags & ELDF_RW) != 0) return EE_OK;
421		422
422	// printf("set area flags to %d\n", flags);	423	// printf("set area flags to %d\n", flags);
423	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);	424	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);
424	if (rc != 0) {	425	if (rc != 0) {
425	printf("failed to set memory area flags\n");	426	printf("failed to set memory area flags\n");
426	return EE_MEMORY;	427	return EE_MEMORY;
427	}	428	}
428		429
429	if (flags & AS_AREA_EXEC) {	430	if (flags & AS_AREA_EXEC) {
430	/* Enforce SMC coherence for the segment */	431	/* Enforce SMC coherence for the segment */
431	if (smc_coherence(entry->p_vaddr + bias, entry->p_filesz))	432	if (smc_coherence(entry->p_vaddr + bias, entry->p_filesz))
432	return EE_MEMORY;	433	return EE_MEMORY;
433	}	434	}
434		435
435	return EE_OK;	436	return EE_OK;
436	}	437	}
437		438
438	/** Process section header.	439	/** Process section header.
439	*	440	*
440	* @param elf Loader state.	441	* @param elf Loader state.
441	* @param entry Segment header.	442	* @param entry Segment header.
442	*	443	*
443	* @return EE_OK on success, error code otherwise.	444	* @return EE_OK on success, error code otherwise.
444	*/	445	*/
445	static int section_header(elf_ld_t elf, elf_section_header_t entry)	446	static int section_header(elf_ld_t elf, elf_section_header_t entry)
446	{	447	{
447	switch (entry->sh_type) {	448	switch (entry->sh_type) {
448	case SHT_PROGBITS:	449	case SHT_PROGBITS:
449	if (entry->sh_flags & SHF_TLS) {	450	if (entry->sh_flags & SHF_TLS) {
450	/* .tdata */	451	/* .tdata */
451	}	452	}
452	break;	453	break;
453	case SHT_NOBITS:	454	case SHT_NOBITS:
454	if (entry->sh_flags & SHF_TLS) {	455	if (entry->sh_flags & SHF_TLS) {
455	/* .tbss */	456	/* .tbss */
456	}	457	}
457	break;	458	break;
458	case SHT_DYNAMIC:	459	case SHT_DYNAMIC:
459	/* Record pointer to dynamic section into info structure */	460	/* Record pointer to dynamic section into info structure */
460	elf->info->dynamic =	461	elf->info->dynamic =
461	(void )((uint8_t )entry->sh_addr + elf->bias);	462	(void )((uint8_t )entry->sh_addr + elf->bias);
462	printf("dynamic section found at 0x%x\n",	463	printf("dynamic section found at 0x%x\n",
463	(uintptr_t)elf->info->dynamic);	464	(uintptr_t)elf->info->dynamic);
464	break;	465	break;
465	default:	466	default:
466	break;	467	break;
467	}	468	}
468		469
469	return EE_OK;	470	return EE_OK;
470	}	471	}
471		472
472	/** @}	473	/** @}
473	*/	474	*/
474		475

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(root)/branches/dynload/uspace/srv/loader/elf_load.c – Rev 3681 → 3686