WebSVN – HelenOS – Diff – /branches/tracing/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, 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;
 
    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 = 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 == "/rtld.so" */
        elf->info->interp = "/rtld.so";
        break;
    case PT_DYNAMIC:
    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.\n");
        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;
    }
 
 
    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:
        /* Record pointer to dynamic section into info structure */
        elf->info->dynamic =
            (void *)((uint8_t *)entry->sh_addr + elf->bias);
        DPRINTF("Dynamic section found at 0x%x.\n",
            (uintptr_t)elf->info->dynamic);
        break;
    default:
        break;
    }
   
    return EE_OK;
}
 
/** @}
 */
 

Rev 3425	Rev 4377
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, elf_info_t info)	104	int elf_load_file(char file_name, size_t so_bias, elf_info_t info)
103	{	105	{
104	elf_ld_t elf;	106	elf_ld_t elf;
105		107
106	int fd;	108	int fd;
107	int rc;	109	int rc;
108		110
109	// printf("open and read '%s'...\n", file_name);	-
110		-
111	fd = open(file_name, O_RDONLY);	111	fd = open(file_name, O_RDONLY);
112	if (fd < 0) {	112	if (fd < 0) {
113	printf("failed opening file\n");	113	DPRINTF("failed opening file\n");
114	return -1;	114	return -1;
115	}	115	}
116		116
117	elf.fd = fd;	117	elf.fd = fd;
118	elf.info = info;	118	elf.info = info;
119		119
120	rc = elf_load(&elf, so_bias);	120	rc = elf_load(&elf, so_bias);
121		121
122	close(fd);	122	close(fd);
123		123
124	return rc;	124	return rc;
125	}	125	}
126		126
127	/** Run an ELF executable.	127	/** Run an ELF executable.
128	*	128	*
129	* Transfers control to the entry point of an ELF executable loaded	129	* Transfers control to the entry point of an ELF executable loaded
130	* earlier with elf_load_file(). This function does not return.	130	* earlier with elf_load_file(). This function does not return.
131	*	131	*
132	* @param info Info structure filled earlier by elf_load_file()	132	* @param info Info structure filled earlier by elf_load_file()
133	*/	133	*/
134	void elf_run(elf_info_t info, pcb_t pcb)	134	void elf_run(elf_info_t info, pcb_t pcb)
135	{	135	{
136	program_run(info->entry, pcb);	136	program_run(info->entry, pcb);
137		137
138	/* not reached */	138	/* not reached */
139	}	139	}
140		140
141	/** Create the program control block (PCB).	141	/** Create the program control block (PCB).
142	*	142	*
143	* Fills the program control block @a pcb with information from	143	* Fills the program control block @a pcb with information from
144	* @a info.	144	* @a info.
145	*	145	*
146	* @param info Program info structure	146	* @param info Program info structure
147	* @return EOK on success or negative error code	147	* @return EOK on success or negative error code
148	*/	148	*/
149	void elf_create_pcb(elf_info_t info, pcb_t pcb)	149	void elf_create_pcb(elf_info_t info, pcb_t pcb)
150	{	150	{
151	pcb->entry = info->entry;	151	pcb->entry = info->entry;
152	pcb->dynamic = info->dynamic;	152	pcb->dynamic = info->dynamic;
153	}	153	}
154		154
155		155
156	/** Load an ELF binary.	156	/** Load an ELF binary.
157	*	157	*
158	* The @a elf structure contains the loader state, including	158	* The @a elf structure contains the loader state, including
159	* an open file, from which the binary will be loaded,	159	* an open file, from which the binary will be loaded,
160	* a pointer to the @c info structure etc.	160	* a pointer to the @c info structure etc.
161	*	161	*
162	* @param elf Pointer to loader state buffer.	162	* @param elf Pointer to loader state buffer.
163	* @param so_bias Bias to use if the file is a shared object.	163	* @param so_bias Bias to use if the file is a shared object.
164	* @return EE_OK on success or EE_xx error code.	164	* @return EE_OK on success or EE_xx error code.
165	*/	165	*/
166	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias)	166	static unsigned int elf_load(elf_ld_t *elf, size_t so_bias)
167	{	167	{
168	elf_header_t header_buf;	168	elf_header_t header_buf;
169	elf_header_t *header = &header_buf;	169	elf_header_t *header = &header_buf;
170	int i, rc;	170	int i, rc;
171		171
172	rc = my_read(elf->fd, header, sizeof(elf_header_t));	172	rc = my_read(elf->fd, header, sizeof(elf_header_t));
173	if (rc < 0) {	173	if (rc < 0) {
174	printf("read error\n");	174	DPRINTF("Read error.\n");
175	return EE_INVALID;	175	return EE_INVALID;
176	}	176	}
177		177
178	elf->header = header;	178	elf->header = header;
179		179
180	// printf("ELF-load:");	-
181	/* Identify ELF */	180	/* Identify ELF */
182	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|	181	if (header->e_ident[EI_MAG0] != ELFMAG0 \|\|
183	header->e_ident[EI_MAG1] != ELFMAG1 \|\|	182	header->e_ident[EI_MAG1] != ELFMAG1 \|\|
184	header->e_ident[EI_MAG2] != ELFMAG2 \|\|	183	header->e_ident[EI_MAG2] != ELFMAG2 \|\|
185	header->e_ident[EI_MAG3] != ELFMAG3) {	184	header->e_ident[EI_MAG3] != ELFMAG3) {
186	printf("invalid header\n");	185	DPRINTF("Invalid header.\n");
187	return EE_INVALID;	186	return EE_INVALID;
188	}	187	}
189		188
190	/* Identify ELF compatibility */	189	/* Identify ELF compatibility */
191	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|	190	if (header->e_ident[EI_DATA] != ELF_DATA_ENCODING \|\|
192	header->e_machine != ELF_MACHINE \|\|	191	header->e_machine != ELF_MACHINE \|\|
193	header->e_ident[EI_VERSION] != EV_CURRENT \|\|	192	header->e_ident[EI_VERSION] != EV_CURRENT \|\|
194	header->e_version != EV_CURRENT \|\|	193	header->e_version != EV_CURRENT \|\|
195	header->e_ident[EI_CLASS] != ELF_CLASS) {	194	header->e_ident[EI_CLASS] != ELF_CLASS) {
196	printf("incompatible data/version/class\n");	195	DPRINTF("Incompatible data/version/class.\n");
197	return EE_INCOMPATIBLE;	196	return EE_INCOMPATIBLE;
198	}	197	}
199		198
200	if (header->e_phentsize != sizeof(elf_segment_header_t)) {	199	if (header->e_phentsize != sizeof(elf_segment_header_t)) {
201	printf("e_phentsize:%d != %d\n", header->e_phentsize,	200	DPRINTF("e_phentsize:%d != %d\n", header->e_phentsize,
202	sizeof(elf_segment_header_t));	201	sizeof(elf_segment_header_t));
203	return EE_INCOMPATIBLE;	202	return EE_INCOMPATIBLE;
204	}	203	}
205		204
206	if (header->e_shentsize != sizeof(elf_section_header_t)) {	205	if (header->e_shentsize != sizeof(elf_section_header_t)) {
207	printf("e_shentsize:%d != %d\n", header->e_shentsize,	206	DPRINTF("e_shentsize:%d != %d\n", header->e_shentsize,
208	sizeof(elf_section_header_t));	207	sizeof(elf_section_header_t));
209	return EE_INCOMPATIBLE;	208	return EE_INCOMPATIBLE;
210	}	209	}
211		210
212	/* Check if the object type is supported. */	211	/* Check if the object type is supported. */
213	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {	212	if (header->e_type != ET_EXEC && header->e_type != ET_DYN) {
214	printf("Object type %d is not supported\n", header->e_type);	213	DPRINTF("Object type %d is not supported\n", header->e_type);
215	return EE_UNSUPPORTED;	214	return EE_UNSUPPORTED;
216	}	215	}
217		216
218	/* Shared objects can be loaded with a bias */	217	/* Shared objects can be loaded with a bias */
219	// printf("Object type: %d\n", header->e_type);	-
220	if (header->e_type == ET_DYN)	218	if (header->e_type == ET_DYN)
221	elf->bias = so_bias;	219	elf->bias = so_bias;
222	else	220	else
223	elf->bias = 0;	221	elf->bias = 0;
224		222
225	// printf("Bias set to 0x%x\n", elf->bias);	-
226	elf->info->interp = NULL;	223	elf->info->interp = NULL;
227	elf->info->dynamic = NULL;	224	elf->info->dynamic = NULL;
228		225
229	// printf("parse segments\n");	-
230		-
231	/* Walk through all segment headers and process them. */	226	/* Walk through all segment headers and process them. */
232	for (i = 0; i < header->e_phnum; i++) {	227	for (i = 0; i < header->e_phnum; i++) {
233	elf_segment_header_t segment_hdr;	228	elf_segment_header_t segment_hdr;
234		229
235	/* Seek to start of segment header */	230	/* Seek to start of segment header */
236	lseek(elf->fd, header->e_phoff	231	lseek(elf->fd, header->e_phoff
237	+ i * sizeof(elf_segment_header_t), SEEK_SET);	232	+ i * sizeof(elf_segment_header_t), SEEK_SET);
238		233
239	rc = my_read(elf->fd, &segment_hdr,	234	rc = my_read(elf->fd, &segment_hdr,
240	sizeof(elf_segment_header_t));	235	sizeof(elf_segment_header_t));
241	if (rc < 0) {	236	if (rc < 0) {
242	printf("read error\n");	237	DPRINTF("Read error.\n");
243	return EE_INVALID;	238	return EE_INVALID;
244	}	239	}
245		240
246	rc = segment_header(elf, &segment_hdr);	241	rc = segment_header(elf, &segment_hdr);
247	if (rc != EE_OK)	242	if (rc != EE_OK)
248	return rc;	243	return rc;
249	}	244	}
250		245
251	// printf("parse sections\n");	246	DPRINTF("Parse sections.\n");
252		247
253	/* Inspect all section headers and proccess them. */	248	/* Inspect all section headers and proccess them. */
254	for (i = 0; i < header->e_shnum; i++) {	249	for (i = 0; i < header->e_shnum; i++) {
255	elf_section_header_t section_hdr;	250	elf_section_header_t section_hdr;
256		251
257	/* Seek to start of section header */	252	/* Seek to start of section header */
258	lseek(elf->fd, header->e_shoff	253	lseek(elf->fd, header->e_shoff
259	+ i * sizeof(elf_section_header_t), SEEK_SET);	254	+ i * sizeof(elf_section_header_t), SEEK_SET);
260		255
261	rc = my_read(elf->fd, &section_hdr,	256	rc = my_read(elf->fd, &section_hdr,
262	sizeof(elf_section_header_t));	257	sizeof(elf_section_header_t));
263	if (rc < 0) {	258	if (rc < 0) {
264	printf("read error\n");	259	DPRINTF("Read error.\n");
265	return EE_INVALID;	260	return EE_INVALID;
266	}	261	}
267		262
268	rc = section_header(elf, &section_hdr);	263	rc = section_header(elf, &section_hdr);
269	if (rc != EE_OK)	264	if (rc != EE_OK)
270	return rc;	265	return rc;
271	}	266	}
272		267
273	elf->info->entry =	268	elf->info->entry =
274	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);	269	(entry_point_t)((uint8_t *)header->e_entry + elf->bias);
275		270
276	// printf("done\n");	271	DPRINTF("Done.\n");
277		272
278	return EE_OK;	273	return EE_OK;
279	}	274	}
280		275
281	/** Print error message according to error code.	276	/** Print error message according to error code.
282	*	277	*
283	* @param rc Return code returned by elf_load().	278	* @param rc Return code returned by elf_load().
284	*	279	*
285	* @return NULL terminated description of error.	280	* @return NULL terminated description of error.
286	*/	281	*/
287	char *elf_error(unsigned int rc)	282	char *elf_error(unsigned int rc)
288	{	283	{
289	assert(rc < sizeof(error_codes) / sizeof(char *));	284	assert(rc < sizeof(error_codes) / sizeof(char *));
290		285
291	return error_codes[rc];	286	return error_codes[rc];
292	}	287	}
293		288
294	/** Process segment header.	289	/** Process segment header.
295	*	290	*
296	* @param entry Segment header.	291	* @param entry Segment header.
297	*	292	*
298	* @return EE_OK on success, error code otherwise.	293	* @return EE_OK on success, error code otherwise.
299	*/	294	*/
300	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)	295	static int segment_header(elf_ld_t elf, elf_segment_header_t entry)
301	{	296	{
302	switch (entry->p_type) {	297	switch (entry->p_type) {
303	case PT_NULL:	298	case PT_NULL:
304	case PT_PHDR:	299	case PT_PHDR:
305	break;	300	break;
306	case PT_LOAD:	301	case PT_LOAD:
307	return load_segment(elf, entry);	302	return load_segment(elf, entry);
308	break;	303	break;
309	case PT_INTERP:	304	case PT_INTERP:
310	/* Assume silently interp == "/rtld.so" */	305	/* Assume silently interp == "/rtld.so" */
311	elf->info->interp = "/rtld.so";	306	elf->info->interp = "/rtld.so";
312	break;	307	break;
313	case PT_DYNAMIC:	308	case PT_DYNAMIC:
314	case PT_SHLIB:	309	case PT_SHLIB:
315	case PT_NOTE:	310	case PT_NOTE:
316	case PT_LOPROC:	311	case PT_LOPROC:
317	case PT_HIPROC:	312	case PT_HIPROC:
318	default:	313	default:
319	printf("segment p_type %d unknown\n", entry->p_type);	314	DPRINTF("Segment p_type %d unknown.\n", entry->p_type);
320	return EE_UNSUPPORTED;	315	return EE_UNSUPPORTED;
321	break;	316	break;
322	}	317	}
323	return EE_OK;	318	return EE_OK;
324	}	319	}
325		320
326	/** Load segment described by program header entry.	321	/** Load segment described by program header entry.
327	*	322	*
328	* @param elf Loader state.	323	* @param elf Loader state.
329	* @param entry Program header entry describing segment to be loaded.	324	* @param entry Program header entry describing segment to be loaded.
330	*	325	*
331	* @return EE_OK on success, error code otherwise.	326	* @return EE_OK on success, error code otherwise.
332	*/	327	*/
333	int load_segment(elf_ld_t elf, elf_segment_header_t entry)	328	int load_segment(elf_ld_t elf, elf_segment_header_t entry)
334	{	329	{
335	void *a;	330	void *a;
336	int flags = 0;	331	int flags = 0;
337	uintptr_t bias;	332	uintptr_t bias;
338	uintptr_t base;	333	uintptr_t base;
339	size_t mem_sz;	334	size_t mem_sz;
340	int rc;	335	int rc;
341		336
342	// printf("load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,	337	DPRINTF("Load segment at addr 0x%x, size 0x%x\n", entry->p_vaddr,
343	// entry->p_memsz);	338	entry->p_memsz);
344		339
345	bias = elf->bias;	340	bias = elf->bias;
346		341
347	if (entry->p_align > 1) {	342	if (entry->p_align > 1) {
348	if ((entry->p_offset % entry->p_align) !=	343	if ((entry->p_offset % entry->p_align) !=
349	(entry->p_vaddr % entry->p_align)) {	344	(entry->p_vaddr % entry->p_align)) {
350	printf("align check 1 failed offset%%align=%d, "	345	DPRINTF("Align check 1 failed offset%%align=%d, "
351	"vaddr%%align=%d\n",	346	"vaddr%%align=%d\n",
352	entry->p_offset % entry->p_align,	347	entry->p_offset % entry->p_align,
353	entry->p_vaddr % entry->p_align	348	entry->p_vaddr % entry->p_align
354	);	349	);
355	return EE_INVALID;	350	return EE_INVALID;
356	}	351	}
357	}	352	}
358		353
359	/* Final flags that will be set for the memory area */	354	/* Final flags that will be set for the memory area */
360		355
361	if (entry->p_flags & PF_X)	356	if (entry->p_flags & PF_X)
362	flags \|= AS_AREA_EXEC;	357	flags \|= AS_AREA_EXEC;
363	if (entry->p_flags & PF_W)	358	if (entry->p_flags & PF_W)
364	flags \|= AS_AREA_WRITE;	359	flags \|= AS_AREA_WRITE;
365	if (entry->p_flags & PF_R)	360	if (entry->p_flags & PF_R)
366	flags \|= AS_AREA_READ;	361	flags \|= AS_AREA_READ;
367	flags \|= AS_AREA_CACHEABLE;	362	flags \|= AS_AREA_CACHEABLE;
368		363
369	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);	364	base = ALIGN_DOWN(entry->p_vaddr, PAGE_SIZE);
370	mem_sz = entry->p_memsz + (entry->p_vaddr - base);	365	mem_sz = entry->p_memsz + (entry->p_vaddr - base);
371		366
372	// printf("map to p_vaddr=0x%x-0x%x...\n", entry->p_vaddr + bias,	367	DPRINTF("Map to p_vaddr=0x%x-0x%x.\n", entry->p_vaddr + bias,
373	// entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));	368	entry->p_vaddr + bias + ALIGN_UP(entry->p_memsz, PAGE_SIZE));
374		369
375	/*	370	/*
376	* For the course of loading, the area needs to be readable	371	* For the course of loading, the area needs to be readable
377	* and writeable.	372	* and writeable.
378	*/	373	*/
379	a = as_area_create((uint8_t *)base + bias, mem_sz,	374	a = as_area_create((uint8_t *)base + bias, mem_sz,
380	AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);	375	AS_AREA_READ \| AS_AREA_WRITE \| AS_AREA_CACHEABLE);
381	if (a == (void *)(-1)) {	376	if (a == (void *)(-1)) {
382	printf("memory mapping failed\n");	377	DPRINTF("Memory mapping failed.\n");
383	return EE_MEMORY;	378	return EE_MEMORY;
384	}	379	}
385		380
386	// printf("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",	381	DPRINTF("as_area_create(0x%lx, 0x%x, %d) -> 0x%lx\n",
387	// entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);	382	entry->p_vaddr+bias, entry->p_memsz, flags, (uintptr_t)a);
388		383
389	/*	384	/*
390	* Load segment data	385	* Load segment data
391	*/	386	*/
392	// printf("seek to %d\n", entry->p_offset);	-
393	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);	387	rc = lseek(elf->fd, entry->p_offset, SEEK_SET);
394	if (rc < 0) {	388	if (rc < 0) {
395	printf("seek error\n");	389	printf("seek error\n");
396	return EE_INVALID;	390	return EE_INVALID;
397	}	391	}
398		392
399	// printf("read 0x%x bytes to address 0x%x\n", entry->p_filesz, entry->p_vaddr+bias);	-
400	/* rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);	393	/* rc = read(fd, (void *)(entry->p_vaddr + bias), entry->p_filesz);
401	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/	394	if (rc < 0) { printf("read error\n"); return EE_INVALID; }*/
402		395
403	/* Long reads are not possible yet. Load segment picewise */	396	/* Long reads are not possible yet. Load segment piecewise. */
404		397
405	unsigned left, now;	398	unsigned left, now;
406	uint8_t *dp;	399	uint8_t *dp;
407		400
408	left = entry->p_filesz;	401	left = entry->p_filesz;
409	dp = (uint8_t *)(entry->p_vaddr + bias);	402	dp = (uint8_t *)(entry->p_vaddr + bias);
410		403
411	while (left > 0) {	404	while (left > 0) {
412	now = 16384;	405	now = 16384;
413	if (now > left) now = left;	406	if (now > left) now = left;
414		407
415	// printf("read %d...", now);	-
416	rc = my_read(elf->fd, dp, now);	408	rc = my_read(elf->fd, dp, now);
417	// printf("->%d\n", rc);	-
418		409
419	if (rc < 0) {	410	if (rc < 0) {
420	printf("read error\n");	411	DPRINTF("Read error.\n");
421	return EE_INVALID;	412	return EE_INVALID;
422	}	413	}
423		414
424	left -= now;	415	left -= now;
425	dp += now;	416	dp += now;
426	}	417	}
427		418
428	// printf("set area flags to %d\n", flags);	-
429	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);	419	rc = as_area_change_flags((uint8_t *)entry->p_vaddr + bias, flags);
430	if (rc != 0) {	420	if (rc != 0) {
431	printf("failed to set memory area flags\n");	421	DPRINTF("Failed to set memory area flags.\n");
432	return EE_MEMORY;	422	return EE_MEMORY;
433	}	423	}
434		424
435	if (flags & AS_AREA_EXEC) {	425	if (flags & AS_AREA_EXEC) {
436	/* Enforce SMC coherence for the segment */	426	/* Enforce SMC coherence for the segment */
437	if (smc_coherence(entry->p_vaddr + bias, entry->p_filesz))	427	if (smc_coherence(entry->p_vaddr + bias, entry->p_filesz))
438	return EE_MEMORY;	428	return EE_MEMORY;
439	}	429	}
440		430
441	return EE_OK;	431	return EE_OK;
442	}	432	}
443		433
444	/** Process section header.	434	/** Process section header.
445	*	435	*
446	* @param elf Loader state.	436	* @param elf Loader state.
447	* @param entry Segment header.	437	* @param entry Segment header.
448	*	438	*
449	* @return EE_OK on success, error code otherwise.	439	* @return EE_OK on success, error code otherwise.
450	*/	440	*/
451	static int section_header(elf_ld_t elf, elf_section_header_t entry)	441	static int section_header(elf_ld_t elf, elf_section_header_t entry)
452	{	442	{
453	switch (entry->sh_type) {	443	switch (entry->sh_type) {
454	case SHT_PROGBITS:	444	case SHT_PROGBITS:
455	if (entry->sh_flags & SHF_TLS) {	445	if (entry->sh_flags & SHF_TLS) {
456	/* .tdata */	446	/* .tdata */
457	}	447	}
458	break;	448	break;
459	case SHT_NOBITS:	449	case SHT_NOBITS:
460	if (entry->sh_flags & SHF_TLS) {	450	if (entry->sh_flags & SHF_TLS) {
461	/* .tbss */	451	/* .tbss */
462	}	452	}
463	break;	453	break;
464	case SHT_DYNAMIC:	454	case SHT_DYNAMIC:
465	/* Record pointer to dynamic section into info structure */	455	/* Record pointer to dynamic section into info structure */
466	elf->info->dynamic =	456	elf->info->dynamic =
467	(void )((uint8_t )entry->sh_addr + elf->bias);	457	(void )((uint8_t )entry->sh_addr + elf->bias);
468	printf("dynamic section found at 0x%x\n",	458	DPRINTF("Dynamic section found at 0x%x.\n",
469	(uintptr_t)elf->info->dynamic);	459	(uintptr_t)elf->info->dynamic);
470	break;	460	break;
471	default:	461	default:
472	break;	462	break;
473	}	463	}
474		464
475	return EE_OK;	465	return EE_OK;
476	}	466	}
477		467
478	/** @}	468	/** @}
479	*/	469	*/
480		470

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(root)/branches/tracing/uspace/srv/loader/elf_load.c – Rev 3425 → 4377