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"
 
#define DPRINTF(...)
 
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;
 
 
 
    fd = open(file_name, O_RDONLY);
    if (fd < 0) {
        DPRINTF("failed opening file\n");
        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) {
        DPRINTF("Read error.\n");
        return EE_INVALID;
    }
 
    elf->header = header;
 
 
    /* 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) {
        DPRINTF("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) {
        DPRINTF("Incompatible data/version/class.\n");
        return EE_INCOMPATIBLE;
    }
 
    if (header->e_phentsize != sizeof(elf_segment_header_t)) {
        DPRINTF("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)) {
        DPRINTF("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) {
        DPRINTF("Object type %d is not supported\n", header->e_type);
        return EE_UNSUPPORTED;
    }
 
    /* Shared objects can be loaded with a bias */
 
    if (header->e_type == ET_DYN)
        elf->bias = so_bias;
    else
        elf->bias = 0;
 
 
    elf->info->interp = NULL;
    elf->info->dynamic = NULL;
 
 
 
    /* 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) {
            DPRINTF("Read error.\n");
            return EE_INVALID;
        }
 
        rc = segment_header(elf, &segment_hdr);
        if (rc != EE_OK)
            return rc;
    }
 
    DPRINTF("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) {
            DPRINTF("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);
 
    DPRINTF("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:
        /* Record pointer to dynamic section into info structure */
        elf->info->dynamic =
            (void *)((uint8_t *)entry->p_vaddr + elf->bias);
        DPRINTF("dynamic section found at 0x%x\n",
            (uintptr_t)elf->info->dynamic);
        break;
    case 0x70000000:
        /* FIXME: MIPS reginfo */
        break;
    case PT_SHLIB:
    case PT_NOTE:
//  case PT_LOPROC:
//  case PT_HIPROC:
    default:
        DPRINTF("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;
 
    DPRINTF("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)) {
            DPRINTF("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);
 
    DPRINTF("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)) {
        DPRINTF("memory mapping failed (0x%x, %d)\n",
            base+bias, mem_sz);
        return EE_MEMORY;
    }
 
    DPRINTF("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
     */
 
    rc = lseek(elf->fd, entry->p_offset, SEEK_SET);
    if (rc < 0) {
        printf("seek error\n");
        return EE_INVALID;
    }
 
 
/*  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 piecewise. */
 
    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;
 
 
        rc = my_read(elf->fd, dp, now);
 
 
        if (rc < 0) {
            DPRINTF("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) {
        DPRINTF("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:
        break;
    default:
        break;
    }
   
    return EE_OK;
}
 
/** @}
 */
 

Rev 3772	Rev 4338
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	#define DPRINTF(...)
-		61
60	static char *error_codes[] = {	62	static char *error_codes[] = {
61	"no error",	63	"no error",
62	"invalid image",	64	"invalid image",
63	"address space error",	65	"address space error",
64	"incompatible image",	66	"incompatible image",
65	"unsupported image type",	67	"unsupported image type",
66	"irrecoverable error"	68	"irrecoverable error"
67	};	69	};
68		70
69	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias);	71	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);	72	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);	73	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);	74	static int load_segment(elf_ld_t elf, elf_segment_header_t entry);
73		75
74	/** Read until the buffer is read in its entirety. */	76	/** Read until the buffer is read in its entirety. */
75	static int my_read(int fd, char *buf, size_t len)	77	static int my_read(int fd, char *buf, size_t len)
76	{	78	{
77	int cnt = 0;	79	int cnt = 0;
78	do {	80	do {
79	buf += cnt;	81	buf += cnt;
80	len -= cnt;	82	len -= cnt;
81	cnt = read(fd, buf, len);	83	cnt = read(fd, buf, len);
82	} while ((cnt > 0) && ((len - cnt) > 0));	84	} while ((cnt > 0) && ((len - cnt) > 0));
83		85
84	return cnt;	86	return cnt;
85	}	87	}
86		88
87	/** Load ELF binary from a file.	89	/** Load ELF binary from a file.
88	*	90	*
89	* Load an ELF binary from the specified file. If the file is	91	* 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	92	* 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	93	* 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	94	* extracted from the binary is stored in a elf_info_t structure
93	* pointed to by @a info.	95	* pointed to by @a info.
94	*	96	*
95	* @param file_name Path to the ELF file.	97	* @param file_name Path to the ELF file.
96	* @param so_bias Bias to use if the file is a shared object.	98	* @param so_bias Bias to use if the file is a shared object.
97	* @param info Pointer to a structure for storing information	99	* @param info Pointer to a structure for storing information
98	* extracted from the binary.	100	* extracted from the binary.
99	*	101	*
100	* @return EOK on success or negative error code.	102	* @return EOK on success or negative error code.
101	*/	103	*/
102	int elf_load_file(char *file_name, size_t so_bias, eld_flags_t flags,	104	int elf_load_file(char *file_name, size_t so_bias, eld_flags_t flags,
103	elf_info_t *info)	105	elf_info_t *info)
104	{	106	{
105	elf_ld_t elf;	107	elf_ld_t elf;
106		108
107	int fd;	109	int fd;
108	int rc;	110	int rc;
109		111
110	// printf("open and read '%s'...\n", file_name);	-
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	DPRINTF("failed opening file\n");
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	pcb->rtld_runtime = NULL;
142	}	142	}
143		143
144		144
145	/** Load an ELF binary.	145	/** Load an ELF binary.
146	*	146	*
147	* The @a elf structure contains the loader state, including	147	* The @a elf structure contains the loader state, including
148	* an open file, from which the binary will be loaded,	148	* an open file, from which the binary will be loaded,
149	* a pointer to the @c info structure etc.	149	* a pointer to the @c info structure etc.
150	*	150	*
151	* @param elf Pointer to loader state buffer.	151	* @param elf Pointer to loader state buffer.
152	* @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.
153	* @return EE_OK on success or EE_xx error code.	153	* @return EE_OK on success or EE_xx error code.
154	*/	154	*/
155	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)
156	{	156	{
157	elf_header_t header_buf;	157	elf_header_t header_buf;
158	elf_header_t *header = &header_buf;	158	elf_header_t *header = &header_buf;
159	int i, rc;	159	int i, rc;
160		160
161	rc = my_read(elf->fd, header, sizeof(elf_header_t));	161	rc = my_read(elf->fd, header, sizeof(elf_header_t));
162	if (rc < 0) {	162	if (rc < 0) {
163	printf("read error\n");	163	DPRINTF("Read error.\n");
164	return EE_INVALID;	164	return EE_INVALID;
165	}	165	}
166		166
167	elf->header = header;	167	elf->header = header;
168		168
169	// printf("ELF-load:");	-
170	/* Identify ELF */	169	/* Identify ELF */
171	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|	170	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|
172	header->e_ident[EI_MAG1] != ELFMAG1 \|\|	171	header->e_ident[EI_MAG1] != ELFMAG1 \|\|
173	header->e_ident[EI_MAG2] != ELFMAG2 \|\|	172	header->e_ident[EI_MAG2] != ELFMAG2 \|\|
174	header->e_ident[EI_MAG3] != ELFMAG3) {	173	header->e_ident[EI_MAG3] != ELFMAG3) {
175	printf("invalid header\n");	174	DPRINTF("Invalid header.\n");
176	return EE_INVALID;	175	return EE_INVALID;
177	}	176	}
178		177
179	/* Identify ELF compatibility */	178	/* Identify ELF compatibility */
180	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|	179	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|
181	header->e_machine != ELF_MACHINE \|\|	180	header->e_machine != ELF_MACHINE \|\|
182	header->e_ident[EI_VERSION] != EV_CURRENT \|\|	181	header->e_ident[EI_VERSION] != EV_CURRENT \|\|
183	header->e_version != EV_CURRENT \|\|	182	header->e_version != EV_CURRENT \|\|
184	header->e_ident[EI_CLASS] != ELF_CLASS) {	183	header->e_ident[EI_CLASS] != ELF_CLASS) {
185	printf("incompatible data/version/class\n");	184	DPRINTF("Incompatible data/version/class.\n");
186	return EE_INCOMPATIBLE;	185	return EE_INCOMPATIBLE;
187	}	186	}
188		187
189	if (header->e_phentsize != sizeof(elf_segment_header_t)) {	188	if (header->e_phentsize != sizeof(elf_segment_header_t)) {
190	printf("e_phentsize:%d != %d\n", header->e_phentsize,	189	DPRINTF("e_phentsize:%d != %d\n", header->e_phentsize,
191	sizeof(elf_segment_header_t));	190	sizeof(elf_segment_header_t));
192	return EE_INCOMPATIBLE;	191	return EE_INCOMPATIBLE;
193	}	192	}
194		193
195	if (header->e_shentsize != sizeof(elf_section_header_t)) {	194	if (header->e_shentsize != sizeof(elf_section_header_t)) {
196	printf("e_shentsize:%d != %d\n", header->e_shentsize,	195	DPRINTF("e_shentsize:%d != %d\n", header->e_shentsize,
197	sizeof(elf_section_header_t));	196	sizeof(elf_section_header_t));
198	return EE_INCOMPATIBLE;	197	return EE_INCOMPATIBLE;
199	}	198	}
200		199
201	/* Check if the object type is supported. */	200	/* Check if the object type is supported. */
202	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {	201	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {
203	printf("Object type %d is not supported\n", header->e_type);	202	DPRINTF("Object type %d is not supported\n", header->e_type);
204	return EE_UNSUPPORTED;	203	return EE_UNSUPPORTED;
205	}	204	}
206		205
207	/* Shared objects can be loaded with a bias */	206	/* Shared objects can be loaded with a bias */
208	// printf("Object type: %d\n", header->e_type);	-
209	if (header->e_type == ET_DYN)	207	if (header->e_type == ET_DYN)
210	elf->bias = so_bias;	208	elf->bias = so_bias;
211	else	209	else
212	elf->bias = 0;	210	elf->bias = 0;
213		211
214	// printf("Bias set to 0x%x\n", elf->bias);	-
215	elf->info->interp = NULL;	212	elf->info->interp = NULL;
216	elf->info->dynamic = NULL;	213	elf->info->dynamic = NULL;
217		214
218	// printf("parse segments\n");	-
219		-
220	/* Walk through all segment headers and process them. */	215	/* Walk through all segment headers and process them. */
221	for (i = 0; i < header->e_phnum; i++) {	216	for (i = 0; i < header->e_phnum; i++) {
222	elf_segment_header_t segment_hdr;	217	elf_segment_header_t segment_hdr;
223		218
224	/* Seek to start of segment header */	219	/* Seek to start of segment header */
225	lseek(elf->fd, header->e_phoff	220	lseek(elf->fd, header->e_phoff
226	+ i * sizeof(elf_segment_header_t), SEEK_SET);	221	+ i * sizeof(elf_segment_header_t), SEEK_SET);
227		222
228	rc = my_read(elf->fd, &segment_hdr,	223	rc = my_read(elf->fd, &segment_hdr,
229	sizeof(elf_segment_header_t));	224	sizeof(elf_segment_header_t));
230	if (rc < 0) {	225	if (rc < 0) {
231	printf("read error\n");	226	DPRINTF("Read error.\n");
232	return EE_INVALID;	227	return EE_INVALID;
233	}	228	}
234		229
235	rc = segment_header(elf, &segment_hdr);	230	rc = segment_header(elf, &segment_hdr);
236	if (rc != EE_OK)	231	if (rc != EE_OK)
237	return rc;	232	return rc;
238	}	233	}
239		234
240	// printf("parse sections\n");	235	DPRINTF("Parse sections.\n");
241		236
242	/* Inspect all section headers and proccess them. */	237	/* Inspect all section headers and proccess them. */
243	for (i = 0; i < header->e_shnum; i++) {	238	for (i = 0; i < header->e_shnum; i++) {
244	elf_section_header_t section_hdr;	239	elf_section_header_t section_hdr;
245		240
246	/* Seek to start of section header */	241	/* Seek to start of section header */
247	lseek(elf->fd, header->e_shoff	242	lseek(elf->fd, header->e_shoff
248	+ i * sizeof(elf_section_header_t), SEEK_SET);	243	+ i * sizeof(elf_section_header_t), SEEK_SET);
249		244
250	rc = my_read(elf->fd, &section_hdr,	245	rc = my_read(elf->fd, &section_hdr,
251	sizeof(elf_section_header_t));	246	sizeof(elf_section_header_t));
252	if (rc < 0) {	247	if (rc < 0) {
253	printf("read error\n");	248	DPRINTF("Read error.\n");
254	return EE_INVALID;	249	return EE_INVALID;
255	}	250	}
256		251
257	rc = section_header(elf, &section_hdr);	252	rc = section_header(elf, &section_hdr);
258	if (rc != EE_OK)	253	if (rc != EE_OK)
259	return rc;	254	return rc;
260	}	255	}
261		256
262	elf->info->entry =	257	elf->info->entry =
263	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);	258	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);
264		259
265	// printf("done\n");	260	DPRINTF("Done.\n");
266		261
267	return EE_OK;	262	return EE_OK;
268	}	263	}
269		264
270	/** Print error message according to error code.	265	/** Print error message according to error code.
271	*	266	*
272	* @param rc Return code returned by elf_load().	267	* @param rc Return code returned by elf_load().
273	*	268	*
274	* @return NULL terminated description of error.	269	* @return NULL terminated description of error.
275	*/	270	*/
276	char *elf_error(unsigned int rc)	271	char *elf_error(unsigned int rc)
277	{	272	{
278	assert(rc < sizeof(error_codes) / sizeof(char *));	273	assert(rc < sizeof(error_codes) / sizeof(char *));
279		274
280	return error_codes[rc];	275	return error_codes[rc];
281	}	276	}
282		277
283	/** Process segment header.	278	/** Process segment header.
284	*	279	*
285	* @param entry Segment header.	280	* @param entry Segment header.
286	*	281	*
287	* @return EE_OK on success, error code otherwise.	282	* @return EE_OK on success, error code otherwise.
288	*/	283	*/
289	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)	284	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)
290	{	285	{
291	switch (entry->p_type) {	286	switch (entry->p_type) {
292	case PT_NULL:	287	case PT_NULL:
293	case PT_PHDR:	288	case PT_PHDR:
294	break;	289	break;
295	case PT_LOAD:	290	case PT_LOAD:
296	return load_segment(elf, entry);	291	return load_segment(elf, entry);
297	break;	292	break;
298	case PT_INTERP:	293	case PT_INTERP:
299	/* Assume silently interp == "/app/dload" */	294	/* Assume silently interp == "/app/dload" */
300	elf->info->interp = "/app/dload";	295	elf->info->interp = "/app/dload";
301	break;	296	break;
302	case PT_DYNAMIC:	297	case PT_DYNAMIC:
303	/* Record pointer to dynamic section into info structure */	298	/* Record pointer to dynamic section into info structure */
304	elf->info->dynamic =	299	elf->info->dynamic =
305	(void )((uint8_t )entry->p_vaddr + elf->bias);	300	(void )((uint8_t )entry->p_vaddr + elf->bias);
306	printf("dynamic section found at 0x%x\n",	301	DPRINTF("dynamic section found at 0x%x\n",
307	(uintptr_t)elf->info->dynamic);	302	(uintptr_t)elf->info->dynamic);
308	break;	303	break;
309	case 0x70000000:	304	case 0x70000000:
310	/* FIXME: MIPS reginfo */	305	/* FIXME: MIPS reginfo */
311	break;	306	break;
312	case PT_SHLIB:	307	case PT_SHLIB:
313	case PT_NOTE:	308	case PT_NOTE:
314	// case PT_LOPROC:	309	// case PT_LOPROC:
315	// case PT_HIPROC:	310	// case PT_HIPROC:
316	default:	311	default:
317	printf("segment p_type %d unknown\n", entry->p_type);	312	DPRINTF("Segment p_type %d unknown.\n", entry->p_type);
318	return EE_UNSUPPORTED;	313	return EE_UNSUPPORTED;
319	break;	314	break;
320	}	315	}
321	return EE_OK;	316	return EE_OK;
322	}	317	}
323		318
324	/** Load segment described by program header entry.	319	/** Load segment described by program header entry.
325	*	320	*
326	* @param elf Loader state.	321	* @param elf Loader state.
327	* @param entry Program header entry describing segment to be loaded.	322	* @param entry Program header entry describing segment to be loaded.
328	*	323	*
329	* @return EE_OK on success, error code otherwise.	324	* @return EE_OK on success, error code otherwise.
330	*/	325	*/
331	int load_segment(elf_ld_t elf, elf_segment_header_t entry)	326	int load_segment(elf_ld_t elf, elf_segment_header_t entry)
332	{	327	{
333	void *a;	328	void *a;
334	int flags = 0;	329	int flags = 0;
335	uintptr_t bias;	330	uintptr_t bias;
336	uintptr_t base;	331	uintptr_t base;
337	size_t mem_sz;	332	size_t mem_sz;
338	int rc;	333	int rc;
339		334
340	// printf("load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,	335	DPRINTF("Load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,
341	// entry->p_memsz);	336	entry->p_memsz);
342		337
343	bias = elf->bias;	338	bias = elf->bias;
344		339
345	if (entry->p_align > 1) {	340	if (entry->p_align > 1) {
346	if ((entry->p_offset % entry->p_align) !=	341	if ((entry->p_offset % entry->p_align) !=
347	(entry->p_vaddr % entry->p_align)) {	342	(entry->p_vaddr % entry->p_align)) {
348	printf("align check 1 failed offset%%align=%d, "	343	DPRINTF("Align check 1 failed offset%%align=%d, "
349	"vaddr%%align=%d\n",	344	"vaddr%%align=%d\n",
350	entry->p_offset % entry->p_align,	345	entry->p_offset % entry->p_align,
351	entry->p_vaddr % entry->p_align	346	entry->p_vaddr % entry->p_align
352	);	347	);
353	return EE_INVALID;	348	return EE_INVALID;
354	}	349	}
355	}	350	}
356		351
357	/* Final flags that will be set for the memory area */	352	/* Final flags that will be set for the memory area */
358		353
359	if (entry->p_flags & PF_X)	354	if (entry->p_flags & PF_X)
360	flags \|= AS_AREA_EXEC;	355	flags \|= AS_AREA_EXEC;
361	if (entry->p_flags & PF_W)	356	if (entry->p_flags & PF_W)
362	flags \|= AS_AREA_WRITE;	357	flags \|= AS_AREA_WRITE;
363	if (entry->p_flags & PF_R)	358	if (entry->p_flags & PF_R)
364	flags \|= AS_AREA_READ;	359	flags \|= AS_AREA_READ;
365	flags \|= AS_AREA_CACHEABLE;	360	flags \|= AS_AREA_CACHEABLE;
366		361
367	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);	362	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);
368	mem_sz = entry->p_memsz + (entry->p_vaddr - base);	363	mem_sz = entry->p_memsz + (entry->p_vaddr - base);
369		364
370	// printf("map to p_vaddr=0x%x-0x%x...\n", entry->p_vaddr + bias,	365	DPRINTF("Map to p_vaddr=0x%x-0x%x.\n", entry->p_vaddr + bias,
371	// entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));	366	entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));
372		367
373	/*	368	/*
374	* For the course of loading, the area needs to be readable	369	* For the course of loading, the area needs to be readable
375	* and writeable.	370	* and writeable.
376	*/	371	*/
377	a = as_area_create((uint8_t *)base + bias, mem_sz,	372	a = as_area_create((uint8_t *)base + bias, mem_sz,
378	AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);	373	AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);
379	if (a == (void *)(-1)) {	374	if (a == (void *)(-1)) {
380	printf("memory mapping failed (0x%x, %d)\n",	375	DPRINTF("memory mapping failed (0x%x, %d)\n",
381	base+bias, mem_sz);	376	base+bias, mem_sz);
382	return EE_MEMORY;	377	return EE_MEMORY;
383	}	378	}
384		379
385	// printf("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",	380	DPRINTF("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",
386	// entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);	381	entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);
387		382
388	/*	383	/*
389	* Load segment data	384	* Load segment data
390	*/	385	*/
391	// printf("seek to %d\n", entry->p_offset);	-
392	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);	386	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);
393	if (rc < 0) {	387	if (rc < 0) {
394	printf("seek error\n");	388	printf("seek error\n");
395	return EE_INVALID;	389	return EE_INVALID;
396	}	390	}
397		391
398	// printf("read 0x%x bytes to address 0x%x\n", entry->p_filesz, entry->p_vaddr+bias);	-
399	/* rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);	392	/* rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);
400	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/	393	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/
401		394
402	/* Long reads are not possible yet. Load segment picewise */	395	/* Long reads are not possible yet. Load segment piecewise. */
403		396
404	unsigned left, now;	397	unsigned left, now;
405	uint8_t *dp;	398	uint8_t *dp;
406		399
407	left = entry->p_filesz;	400	left = entry->p_filesz;
408	dp = (uint8_t *)(entry->p_vaddr + bias);	401	dp = (uint8_t *)(entry->p_vaddr + bias);
409		402
410	while (left > 0) {	403	while (left > 0) {
411	now = 16384;	404	now = 16384;
412	if (now > left) now = left;	405	if (now > left) now = left;
413		406
414	// printf("read %d...", now);	-
415	rc = my_read(elf->fd, dp, now);	407	rc = my_read(elf->fd, dp, now);
416	// printf("->%d\n", rc);	-
417		408
418	if (rc < 0) {	409	if (rc < 0) {
419	printf("read error\n");	410	DPRINTF("Read error.\n");
420	return EE_INVALID;	411	return EE_INVALID;
421	}	412	}
422		413
423	left -= now;	414	left -= now;
424	dp += now;	415	dp += now;
425	}	416	}
426		417
427	/*	418	/*
428	* The caller wants to modify the segments first. He will then	419	* The caller wants to modify the segments first. He will then
429	* need to set the right access mode and ensure SMC coherence.	420	* need to set the right access mode and ensure SMC coherence.
430	*/	421	*/
431	if ((elf->flags & ELDF_RW) != 0) return EE_OK;	422	if ((elf->flags & ELDF_RW) != 0) return EE_OK;
432		423
433	// printf("set area flags to %d\n", flags);	424	// printf("set area flags to %d\n", flags);
434	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);	425	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);
435	if (rc != 0) {	426	if (rc != 0) {
436	printf("failed to set memory area flags\n");	427	DPRINTF("Failed to set memory area flags.\n");
437	return EE_MEMORY;	428	return EE_MEMORY;
438	}	429	}
439		430
440	if (flags & AS_AREA_EXEC) {	431	if (flags & AS_AREA_EXEC) {
441	/* Enforce SMC coherence for the segment */	432	/* Enforce SMC coherence for the segment */
442	if (smc_coherence(entry->p_vaddr + bias, entry->p_filesz))	433	if (smc_coherence(entry->p_vaddr + bias, entry->p_filesz))
443	return EE_MEMORY;	434	return EE_MEMORY;
444	}	435	}
445		436
446	return EE_OK;	437	return EE_OK;
447	}	438	}
448		439
449	/** Process section header.	440	/** Process section header.
450	*	441	*
451	* @param elf Loader state.	442	* @param elf Loader state.
452	* @param entry Segment header.	443	* @param entry Segment header.
453	*	444	*
454	* @return EE_OK on success, error code otherwise.	445	* @return EE_OK on success, error code otherwise.
455	*/	446	*/
456	static int section_header(elf_ld_t elf, elf_section_header_t entry)	447	static int section_header(elf_ld_t elf, elf_section_header_t entry)
457	{	448	{
458	switch (entry->sh_type) {	449	switch (entry->sh_type) {
459	case SHT_PROGBITS:	450	case SHT_PROGBITS:
460	if (entry->sh_flags & SHF_TLS) {	451	if (entry->sh_flags & SHF_TLS) {
461	/* .tdata */	452	/* .tdata */
462	}	453	}
463	break;	454	break;
464	case SHT_NOBITS:	455	case SHT_NOBITS:
465	if (entry->sh_flags & SHF_TLS) {	456	if (entry->sh_flags & SHF_TLS) {
466	/* .tbss */	457	/* .tbss */
467	}	458	}
468	break;	459	break;
469	case SHT_DYNAMIC:	460	case SHT_DYNAMIC:
470	break;	461	break;
471	default:	462	default:
472	break;	463	break;
473	}	464	}
474		465
475	return EE_OK;	466	return EE_OK;
476	}	467	}
477		468
478	/** @}	469	/** @}
479	*/	470	*/
480		471

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(root)/branches/dynload/uspace/srv/loader/elf_load.c @ 3772 – Rev 3772 → 4338