Head

GCC Code Coverage Report

Directory:	./		Exec	Total	Coverage
File:	usr.sbin/kvm_mkdb/nlist.c	Lines:	0	127	0.0 %
Date:	2017-11-13	Branches:	0	106	0.0 %


/*	$OpenBSD: nlist.c,v 1.51 2017/10/27 16:47:08 mpi Exp $	*/

/*-
 * Copyright (c) 1990, 1993
 *	The Regents of the University of California.  All rights reserved.
 *
 * Redistribution and use in source and binary forms, with or without
 * modification, are permitted provided that the following conditions
 * are met:
 * 1. Redistributions of source code must retain the above copyright
 *    notice, this list of conditions and the following disclaimer.
 * 2. 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.
 * 3. Neither the name of the University nor the names of its contributors
 *    may be used to endorse or promote products derived from this software
 *    without specific prior written permission.
 *
 * THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``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 REGENTS OR CONTRIBUTORS 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.
 */

#include <sys/types.h>

#include <db.h>
#include <err.h>
#include <errno.h>
#include <fcntl.h>
#include <kvm.h>
#include <limits.h>
#include <paths.h>
#include <stdio.h>
#include <stdlib.h>
#include <string.h>
#include <unistd.h>

#include "extern.h"

#include <sys/mman.h>
#include <sys/stat.h>
#include <sys/file.h>
#include <sys/sysctl.h>

#include <elf.h>

typedef struct nlist NLIST;
#define	_strx	n_un.n_strx
#define	_name	n_un.n_name

static char *kfile;
static char *fmterr;

int	__elf_knlist(int fd, DB *db, int ksyms);

int
__elf_knlist(int fd, DB *db, int ksyms)
{
	caddr_t strtab = NULL;
	off_t symstroff, symoff;
	u_long symsize, symstrsize;
	u_long kernvma, kernoffs;
	int i, error = 0;
	Elf32_Word j;
	Elf_Sym sbuf;
	char buf[1024];
	Elf_Ehdr eh;
	Elf_Shdr *sh = NULL;
	DBT data, key;
	NLIST nbuf;
	FILE *fp;
	int usemalloc = 0;

	if ((fp = fdopen(fd, "r")) == NULL)
		err(1, "%s", kfile);

	if (fseek(fp, (off_t)0, SEEK_SET) == -1 ||
	    fread(&eh, sizeof(eh), 1, fp) != 1 ||
	    !IS_ELF(eh)) {
		fclose(fp);
		return (1);
	}

	sh = calloc(sizeof(Elf_Shdr), eh.e_shnum);
	if (sh == NULL)
		errx(1, "cannot allocate %zu bytes for symbol header",
		    sizeof(Elf_Shdr) * eh.e_shnum);

	if (fseek (fp, eh.e_shoff, SEEK_SET) < 0) {
		fmterr = "no exec header";
		error = -1;
		goto done;
	}

	if (fread(sh, sizeof(Elf_Shdr) * eh.e_shnum, 1, fp) != 1) {
		fmterr = "no exec header";
		error = -1;
		goto done;
	}

	symstrsize = symsize = 0;
	kernvma = (u_long)-1;	/* 0 is a valid value (at least on hp300) */
	for (i = 0; i < eh.e_shnum; i++) {
		if (sh[i].sh_type == SHT_STRTAB) {
			for (j = 0; j < eh.e_shnum; j++)
				if (sh[j].sh_type == SHT_SYMTAB &&
				    sh[j].sh_link == (unsigned)i) {
					symstroff = sh[i].sh_offset;
					symstrsize = sh[i].sh_size;
			}
		} else if (sh[i].sh_type == SHT_SYMTAB) {
			symoff = sh[i].sh_offset;
			symsize = sh[i].sh_size;
		} else if (sh[i].sh_type == SHT_PROGBITS &&
		    (sh[i].sh_flags & SHF_EXECINSTR)) {
			kernvma = sh[i].sh_addr;
			kernoffs = sh[i].sh_offset;
		}
	}

	if (symstrsize == 0 || symsize == 0 || kernvma == (u_long)-1) {
		fmterr = "corrupt file";
		error = -1;
		goto done;
	}

	/*
	 * Map string table into our address space.  This gives us
	 * an easy way to randomly access all the strings, without
	 * making the memory allocation permanent as with malloc/free
	 * (i.e., munmap will return it to the system).
	 *
	 * XXX - we really want to check if this is a regular file.
	 *	 then we probably want a MAP_PRIVATE here.
	 */
	strtab = mmap(NULL, (size_t)symstrsize, PROT_READ,
	    MAP_SHARED|MAP_FILE, fileno(fp), symstroff);
	if (strtab == MAP_FAILED) {
		usemalloc = 1;
		if ((strtab = malloc(symstrsize)) == NULL) {
			fmterr = "out of memory";
			error = -1;
			goto done;
		}
		if (fseek(fp, symstroff, SEEK_SET) == -1) {
			fmterr = "corrupt file";
			error = -1;
			goto done;
		}
		if (fread(strtab, symstrsize, 1, fp) != 1) {
			fmterr = "corrupt file";
			error = -1;
			goto done;
		}
	}

	if (fseek(fp, symoff, SEEK_SET) == -1) {
		fmterr = "corrupt file";
		error = -1;
		goto done;
	}

	data.data = (u_char *)&nbuf;
	data.size = sizeof(NLIST);

	/* Read each symbol and enter it into the database. */
	while (symsize > 0) {
		symsize -= sizeof(Elf_Sym);
		if (fread((char *)&sbuf, sizeof(sbuf), 1, fp) != 1) {
			if (feof(fp))
				fmterr = "corrupted symbol table";
			else
				warn("%s", kfile);
			error = -1;
			goto done;
		}
		if (!sbuf.st_name)
			continue;

		nbuf.n_value = sbuf.st_value;

		/* XXX type conversion is pretty rude... */
		switch(ELF_ST_TYPE(sbuf.st_info)) {
		case STT_NOTYPE:
			switch (sbuf.st_shndx) {
			case SHN_UNDEF:
				nbuf.n_type = N_UNDF;
				break;
			case SHN_ABS:
				nbuf.n_type = N_ABS;
				break;
			case SHN_COMMON:
				nbuf.n_type = N_COMM;
				break;
			default:
				nbuf.n_type = N_COMM | N_EXT;
				break;
			}
			break;
		case STT_FUNC:
			nbuf.n_type = N_TEXT;
			break;
		case STT_OBJECT:
			nbuf.n_type = N_DATA;
			break;
		case STT_FILE:
			nbuf.n_type = N_FN;
			break;
		}
		if (ELF_ST_BIND(sbuf.st_info) == STB_LOCAL)
			nbuf.n_type = N_EXT;

		*buf = '_';
		strlcpy(buf + 1, strtab + sbuf.st_name, sizeof buf - 1);
		key.data = (u_char *)buf;
		key.size = strlen((char *)key.data);
		if (db->put(db, &key, &data, 0))
			err(1, "record enter");

		if (strcmp((char *)key.data, VRS_SYM) == 0) {
			long cur_off;
			if (!ksyms) {
				/*
				 * Calculate offset to the version string in
				 * the file. kernvma is where the kernel is
				 * really loaded; kernoffs is where in the
				 * file it starts.
				 */
				long voff;
				voff = nbuf.n_value - kernvma + kernoffs;
				cur_off = ftell(fp);
				if (fseek(fp, voff, SEEK_SET) == -1) {
					fmterr = "corrupted string table";
					error = -1;
					goto done;
				}

				/*
				 * Read version string up to, and including
				 * newline. This code assumes that a newline
				 * terminates the version line.
				 */
				if (fgets(buf, sizeof(buf), fp) == NULL) {
					fmterr = "corrupted string table";
					error = -1;
					goto done;
				}
			} else {
				/*
				 * This is /dev/ksyms or a look alike.
				 * Use sysctl() to get version since we
				 * don't have real text or data.
				 */
				int mib[2];
				size_t len;
				char *p;

				mib[0] = CTL_KERN;
				mib[1] = KERN_VERSION;
				len = sizeof(buf);
				if (sysctl(mib, 2, buf, &len, NULL, 0) == -1) {
					err(1, "sysctl can't find kernel "
					    "version string");
				}
				if ((p = strchr(buf, '\n')) != NULL)
					*(p+1) = '\0';
			}

			key.data = (u_char *)VRS_KEY;
			key.size = sizeof(VRS_KEY) - 1;
			data.data = (u_char *)buf;
			data.size = strlen(buf);
			if (db->put(db, &key, &data, 0))
				err(1, "record enter");

			/* Restore to original values. */
			data.data = (u_char *)&nbuf;
			data.size = sizeof(NLIST);
			if (!ksyms && fseek(fp, cur_off, SEEK_SET) == -1) {
				fmterr = "corrupted string table";
				error = -1;
				goto done;
			}
		}
	}
done:
	if (strtab) {
		if (usemalloc)
			free(strtab);
		else
			munmap(strtab, symstrsize);
	}
	(void)fclose(fp);
	free(sh);
	return (error);
}

int
create_knlist(char *name, int fd, DB *db)
{
	int error, ksyms;

	if (strcmp(name, _PATH_KSYMS) == 0) {
		ksyms = 1;
	} else {
		ksyms = 0;
	}

	fmterr = NULL;
	kfile = name;
	/* rval of 1 means wrong executable type */
	error = __elf_knlist(fd, db, ksyms);

	if (fmterr != NULL)
		warnc(EFTYPE, "%s: %s", kfile, fmterr);

	return(error);
}


Generated by: GCOVR (Version 3.3)

Line	Branch	Exec	Source
1			/* $OpenBSD: nlist.c,v 1.51 2017/10/27 16:47:08 mpi Exp $ */
2
3			/*-
4			* Copyright (c) 1990, 1993
5			* The Regents of the University of California. All rights reserved.
6			*
7			* Redistribution and use in source and binary forms, with or without
8			* modification, are permitted provided that the following conditions
9			* are met:
10			* 1. Redistributions of source code must retain the above copyright
11			* notice, this list of conditions and the following disclaimer.
12			* 2. Redistributions in binary form must reproduce the above copyright
13			* notice, this list of conditions and the following disclaimer in the
14			* documentation and/or other materials provided with the distribution.
15			* 3. Neither the name of the University nor the names of its contributors
16			* may be used to endorse or promote products derived from this software
17			* without specific prior written permission.
18			*
19			* THIS SOFTWARE IS PROVIDED BY THE REGENTS AND CONTRIBUTORS ``AS IS'' AND
20			* ANY EXPRESS OR IMPLIED WARRANTIES, INCLUDING, BUT NOT LIMITED TO, THE
21			* IMPLIED WARRANTIES OF MERCHANTABILITY AND FITNESS FOR A PARTICULAR PURPOSE
22			* ARE DISCLAIMED. IN NO EVENT SHALL THE REGENTS OR CONTRIBUTORS BE LIABLE
23			* FOR ANY DIRECT, INDIRECT, INCIDENTAL, SPECIAL, EXEMPLARY, OR CONSEQUENTIAL
24			* DAMAGES (INCLUDING, BUT NOT LIMITED TO, PROCUREMENT OF SUBSTITUTE GOODS
25			* OR SERVICES; LOSS OF USE, DATA, OR PROFITS; OR BUSINESS INTERRUPTION)
26			* HOWEVER CAUSED AND ON ANY THEORY OF LIABILITY, WHETHER IN CONTRACT, STRICT
27			* LIABILITY, OR TORT (INCLUDING NEGLIGENCE OR OTHERWISE) ARISING IN ANY WAY
28			* OUT OF THE USE OF THIS SOFTWARE, EVEN IF ADVISED OF THE POSSIBILITY OF
29			* SUCH DAMAGE.
30			*/
31
32			#include <sys/types.h>
33
34			#include <db.h>
35			#include <err.h>
36			#include <errno.h>
37			#include <fcntl.h>
38			#include <kvm.h>
39			#include <limits.h>
40			#include <paths.h>
41			#include <stdio.h>
42			#include <stdlib.h>
43			#include <string.h>
44			#include <unistd.h>
45
46			#include "extern.h"
47
48			#include <sys/mman.h>
49			#include <sys/stat.h>
50			#include <sys/file.h>
51			#include <sys/sysctl.h>
52
53			#include <elf.h>
54
55			typedef struct nlist NLIST;
56			#define _strx n_un.n_strx
57			#define _name n_un.n_name
58
59			static char *kfile;
60			static char *fmterr;
61
62			int __elf_knlist(int fd, DB *db, int ksyms);
63
64			int
65			__elf_knlist(int fd, DB *db, int ksyms)
66			{
67			caddr_t strtab = NULL;
68			off_t symstroff, symoff;
69			u_long symsize, symstrsize;
70			u_long kernvma, kernoffs;
71			int i, error = 0;
72			Elf32_Word j;
73			Elf_Sym sbuf;
74			char buf[1024];
75			Elf_Ehdr eh;
76			Elf_Shdr *sh = NULL;
77			DBT data, key;
78			NLIST nbuf;
79			FILE *fp;
80			int usemalloc = 0;
81
82			if ((fp = fdopen(fd, "r")) == NULL)
83			err(1, "%s", kfile);
84
85			if (fseek(fp, (off_t)0, SEEK_SET) == -1 \|\|
86			fread(&eh, sizeof(eh), 1, fp) != 1 \|\|
87			!IS_ELF(eh)) {
88			fclose(fp);
89			return (1);
90			}
91
92			sh = calloc(sizeof(Elf_Shdr), eh.e_shnum);
93			if (sh == NULL)
94			errx(1, "cannot allocate %zu bytes for symbol header",
95			sizeof(Elf_Shdr) * eh.e_shnum);
96
97			if (fseek (fp, eh.e_shoff, SEEK_SET) < 0) {
98			fmterr = "no exec header";
99			error = -1;
100			goto done;
101			}
102
103			if (fread(sh, sizeof(Elf_Shdr) * eh.e_shnum, 1, fp) != 1) {
104			fmterr = "no exec header";
105			error = -1;
106			goto done;
107			}
108
109			symstrsize = symsize = 0;
110			kernvma = (u_long)-1; /* 0 is a valid value (at least on hp300) */
111			for (i = 0; i < eh.e_shnum; i++) {
112			if (sh[i].sh_type == SHT_STRTAB) {
113			for (j = 0; j < eh.e_shnum; j++)
114			if (sh[j].sh_type == SHT_SYMTAB &&
115			sh[j].sh_link == (unsigned)i) {
116			symstroff = sh[i].sh_offset;
117			symstrsize = sh[i].sh_size;
118			}
119			} else if (sh[i].sh_type == SHT_SYMTAB) {
120			symoff = sh[i].sh_offset;
121			symsize = sh[i].sh_size;
122			} else if (sh[i].sh_type == SHT_PROGBITS &&
123			(sh[i].sh_flags & SHF_EXECINSTR)) {
124			kernvma = sh[i].sh_addr;
125			kernoffs = sh[i].sh_offset;
126			}
127			}
128
129			if (symstrsize == 0 \|\| symsize == 0 \|\| kernvma == (u_long)-1) {
130			fmterr = "corrupt file";
131			error = -1;
132			goto done;
133			}
134
135			/*
136			* Map string table into our address space. This gives us
137			* an easy way to randomly access all the strings, without
138			* making the memory allocation permanent as with malloc/free
139			* (i.e., munmap will return it to the system).
140			*
141			* XXX - we really want to check if this is a regular file.
142			* then we probably want a MAP_PRIVATE here.
143			*/
144			strtab = mmap(NULL, (size_t)symstrsize, PROT_READ,
145			MAP_SHARED\|MAP_FILE, fileno(fp), symstroff);
146			if (strtab == MAP_FAILED) {
147			usemalloc = 1;
148			if ((strtab = malloc(symstrsize)) == NULL) {
149			fmterr = "out of memory";
150			error = -1;
151			goto done;
152			}
153			if (fseek(fp, symstroff, SEEK_SET) == -1) {
154			fmterr = "corrupt file";
155			error = -1;
156			goto done;
157			}
158			if (fread(strtab, symstrsize, 1, fp) != 1) {
159			fmterr = "corrupt file";
160			error = -1;
161			goto done;
162			}
163			}
164
165			if (fseek(fp, symoff, SEEK_SET) == -1) {
166			fmterr = "corrupt file";
167			error = -1;
168			goto done;
169			}
170
171			data.data = (u_char *)&nbuf;
172			data.size = sizeof(NLIST);
173
174			/* Read each symbol and enter it into the database. */
175			while (symsize > 0) {
176			symsize -= sizeof(Elf_Sym);
177			if (fread((char *)&sbuf, sizeof(sbuf), 1, fp) != 1) {
178			if (feof(fp))
179			fmterr = "corrupted symbol table";
180			else
181			warn("%s", kfile);
182			error = -1;
183			goto done;
184			}
185			if (!sbuf.st_name)
186			continue;
187
188			nbuf.n_value = sbuf.st_value;
189
190			/* XXX type conversion is pretty rude... */
191			switch(ELF_ST_TYPE(sbuf.st_info)) {
192			case STT_NOTYPE:
193			switch (sbuf.st_shndx) {
194			case SHN_UNDEF:
195			nbuf.n_type = N_UNDF;
196			break;
197			case SHN_ABS:
198			nbuf.n_type = N_ABS;
199			break;
200			case SHN_COMMON:
201			nbuf.n_type = N_COMM;
202			break;
203			default:
204			nbuf.n_type = N_COMM \| N_EXT;
205			break;
206			}
207			break;
208			case STT_FUNC:
209			nbuf.n_type = N_TEXT;
210			break;
211			case STT_OBJECT:
212			nbuf.n_type = N_DATA;
213			break;
214			case STT_FILE:
215			nbuf.n_type = N_FN;
216			break;
217			}
218			if (ELF_ST_BIND(sbuf.st_info) == STB_LOCAL)
219			nbuf.n_type = N_EXT;
220
221			*buf = '_';
222			strlcpy(buf + 1, strtab + sbuf.st_name, sizeof buf - 1);
223			key.data = (u_char *)buf;
224			key.size = strlen((char *)key.data);
225			if (db->put(db, &key, &data, 0))
226			err(1, "record enter");
227
228			if (strcmp((char *)key.data, VRS_SYM) == 0) {
229			long cur_off;
230			if (!ksyms) {
231			/*
232			* Calculate offset to the version string in
233			* the file. kernvma is where the kernel is
234			* really loaded; kernoffs is where in the
235			* file it starts.
236			*/
237			long voff;
238			voff = nbuf.n_value - kernvma + kernoffs;
239			cur_off = ftell(fp);
240			if (fseek(fp, voff, SEEK_SET) == -1) {
241			fmterr = "corrupted string table";
242			error = -1;
243			goto done;
244			}
245
246			/*
247			* Read version string up to, and including
248			* newline. This code assumes that a newline
249			* terminates the version line.
250			*/
251			if (fgets(buf, sizeof(buf), fp) == NULL) {
252			fmterr = "corrupted string table";
253			error = -1;
254			goto done;
255			}
256			} else {
257			/*
258			* This is /dev/ksyms or a look alike.
259			* Use sysctl() to get version since we
260			* don't have real text or data.
261			*/
262			int mib[2];
263			size_t len;
264			char *p;
265
266			mib[0] = CTL_KERN;
267			mib[1] = KERN_VERSION;
268			len = sizeof(buf);
269			if (sysctl(mib, 2, buf, &len, NULL, 0) == -1) {
270			err(1, "sysctl can't find kernel "
271			"version string");
272			}
273			if ((p = strchr(buf, '\n')) != NULL)
274			*(p+1) = '\0';
275			}
276
277			key.data = (u_char *)VRS_KEY;
278			key.size = sizeof(VRS_KEY) - 1;
279			data.data = (u_char *)buf;
280			data.size = strlen(buf);
281			if (db->put(db, &key, &data, 0))
282			err(1, "record enter");
283
284			/* Restore to original values. */
285			data.data = (u_char *)&nbuf;
286			data.size = sizeof(NLIST);
287			if (!ksyms && fseek(fp, cur_off, SEEK_SET) == -1) {
288			fmterr = "corrupted string table";
289			error = -1;
290			goto done;
291			}
292			}
293			}
294			done:
295			if (strtab) {
296			if (usemalloc)
297			free(strtab);
298			else
299			munmap(strtab, symstrsize);
300			}
301			(void)fclose(fp);
302			free(sh);
303			return (error);
304			}
305
306			int
307			create_knlist(char name, int fd, DB db)
308			{
309			int error, ksyms;
310
311			if (strcmp(name, _PATH_KSYMS) == 0) {
312			ksyms = 1;
313			} else {
314			ksyms = 0;
315			}
316
317			fmterr = NULL;
318			kfile = name;
319			/* rval of 1 means wrong executable type */
320			error = __elf_knlist(fd, db, ksyms);
321
322			if (fmterr != NULL)
323			warnc(EFTYPE, "%s: %s", kfile, fmterr);
324
325			return(error);
326			}