1 /* 2 * Copryight 1997 Sean Eric Fagan 3 * 4 * Redistribution and use in source and binary forms, with or without 5 * modification, are permitted provided that the following conditions 6 * are met: 7 * 1. Redistributions of source code must retain the above copyright 8 * notice, this list of conditions and the following disclaimer. 9 * 2. Redistributions in binary form must reproduce the above copyright 10 * notice, this list of conditions and the following disclaimer in the 11 * documentation and/or other materials provided with the distribution. 12 * 3. All advertising materials mentioning features or use of this software 13 * must display the following acknowledgement: 14 * This product includes software developed by Sean Eric Fagan 15 * 4. Neither the name of the author may be used to endorse or promote 16 * products derived from this software without specific prior written 17 * permission. 18 * 19 * THIS SOFTWARE IS PROVIDED BY THE AUTHOR 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 AUTHOR 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 #ifndef lint 33 static const char rcsid[] = 34 "$Id: syscalls.c,v 1.5 1998/07/06 21:01:48 bde Exp $"; 35 #endif /* not lint */ 36 37 /* 38 * This file has routines used to print out system calls and their 39 * arguments. 40 */ 41 42 #include <err.h> 43 #include <stdio.h> 44 #include <stdlib.h> 45 #include <string.h> 46 #include <unistd.h> 47 #include <sys/types.h> 48 #include "syscall.h" 49 50 /* 51 * This should probably be in its own file. 52 */ 53 54 struct syscall syscalls[] = { 55 { "readlink", 1, 3, 56 { { String, 0 } , { String | OUT, 1 }, { Int, 2 }}}, 57 { "lseek", 2, 3, 58 { { Int, 0 }, {Quad, 2 }, { Int, 4 }}}, 59 { "mmap", 2, 6, 60 { { Hex, 0 }, {Int, 1}, {Hex, 2}, {Hex, 3}, {Int, 4}, {Quad, 6}}}, 61 { "open", 1, 3, 62 { { String | IN, 0} , { Int, 1}, {Octal, 2}}}, 63 { "linux_open", 1, 3, 64 { { String, 0 }, { Int, 1}, { Octal, 2 }}}, 65 { "close", 1, 1, { { Int, 0 } } }, 66 { "fstat", 1, 2, 67 { { Int, 0}, {Ptr | OUT , 1 }}}, 68 { "stat", 1, 2, 69 { { String | IN, 0 }, { Ptr | OUT, 1 }}}, 70 { "lstat", 1, 2, 71 { { String | IN, 0 }, { Ptr | OUT, 1 }}}, 72 { "linux_newstat", 1, 2, 73 { { String | IN, 0 }, { Ptr | OUT, 1 }}}, 74 { "linux_newfstat", 1, 2, 75 { { Int, 0 }, { Ptr | OUT, 1 }}}, 76 { "write", 1, 3, 77 { { Int, 0}, { Ptr | IN, 1 }, { Int, 2 }}}, 78 { "ioctl", 1, 3, 79 { { Int, 0}, { Ioctl, 1 }, { Hex, 2 }}}, 80 { "break", 1, 1, { { Hex, 0 }}}, 81 { "exit", 0, 1, { { Hex, 0 }}}, 82 { 0, 0, 0, { { 0, 0 }}}, 83 }; 84 85 char * ioctlname __P((int)); 86 87 /* 88 * If/when the list gets big, it might be desirable to do it 89 * as a hash table or binary search. 90 */ 91 92 struct syscall * 93 get_syscall(const char *name) { 94 struct syscall *sc = syscalls; 95 96 while (sc->name) { 97 if (!strcmp(name, sc->name)) 98 return sc; 99 sc++; 100 } 101 return NULL; 102 } 103 104 /* 105 * get_string 106 * Copy a string from the process. Note that it is 107 * expected to be a C string, but if max is set, it will 108 * only get that much. 109 */ 110 111 char * 112 get_string(int procfd, void *offset, int max) { 113 char *buf; 114 int size, len, c; 115 FILE *p; 116 117 if ((p = fdopen(procfd, "r")) == NULL) 118 err(1, "fdopen"); 119 buf = malloc( size = (max ? max : 64 ) ); 120 len = 0; 121 fseek(p, (long)offset, SEEK_SET); 122 while ((c = fgetc(p)) != EOF) { 123 buf[len++] = c; 124 if (c == 0 || len == max) { 125 buf[len] = 0; 126 break; 127 } 128 if (len == size) { 129 char *tmp = buf; 130 tmp = realloc(buf, size+64); 131 if (tmp == NULL) { 132 buf[len] = 0; 133 return buf; 134 } 135 size += 64; 136 } 137 } 138 return buf; 139 } 140 141 142 /* 143 * Gag. This is really unportable. Multiplication is more portable. 144 * But slower, from the code I saw. 145 */ 146 147 static long long 148 make_quad(unsigned long p1, unsigned long p2) { 149 union { 150 long long ll; 151 unsigned long l[2]; 152 } t; 153 t.l[0] = p1; 154 t.l[1] = p2; 155 return t.ll; 156 } 157 158 159 /* 160 * print_arg 161 * Converts a syscall argument into a string. Said string is 162 * allocated via malloc(), so needs to be free()'d. The file 163 * descriptor is for the process' memory (via /proc), and is used 164 * to get any data (where the argument is a pointer). sc is 165 * a pointer to the syscall description (see above); args is 166 * an array of all of the system call arguments. 167 */ 168 169 char * 170 print_arg(int fd, struct syscall_args *sc, unsigned long *args) { 171 char *tmp = NULL; 172 switch (sc->type & ARG_MASK) { 173 case Hex: 174 tmp = malloc(12); 175 sprintf(tmp, "0x%lx", args[sc->offset]); 176 break; 177 case Octal: 178 tmp = malloc(13); 179 sprintf(tmp, "0%lo", args[sc->offset]); 180 break; 181 case Int: 182 tmp = malloc(12); 183 sprintf(tmp, "%ld", args[sc->offset]); 184 break; 185 case String: 186 { 187 char *tmp2; 188 tmp2 = get_string(fd, (void*)args[sc->offset], 0); 189 tmp = malloc(strlen(tmp2) + 3); 190 sprintf(tmp, "\"%s\"", tmp2); 191 free(tmp2); 192 } 193 break; 194 case Quad: 195 { 196 unsigned long long t; 197 unsigned long l1, l2; 198 l1 = args[sc->offset]; 199 l2 = args[sc->offset+1]; 200 t = make_quad(l1, l2); 201 tmp = malloc(24); 202 sprintf(tmp, "0x%qx", t); 203 break; 204 } 205 case Ptr: 206 tmp = malloc(12); 207 sprintf(tmp, "0x%lx", args[sc->offset]); 208 break; 209 case Ioctl: 210 { 211 char *temp = ioctlname(args[sc->offset]); 212 if (temp) 213 tmp = strdup(temp); 214 else { 215 tmp = malloc(12); 216 sprintf(tmp, "0x%lx", args[sc->offset]); 217 } 218 } 219 } 220 return tmp; 221 } 222 223 /* 224 * print_syscall 225 * Print (to outfile) the system call and its arguments. Note that 226 * nargs is the number of arguments (not the number of words; this is 227 * potentially confusing, I know). 228 */ 229 230 void 231 print_syscall(FILE *outfile, const char *name, int nargs, char **s_args) { 232 int i; 233 fprintf(outfile, "syscall %s(", name); 234 for (i = 0; i < nargs; i++) { 235 if (s_args[i]) 236 fprintf(outfile, "%s", s_args[i]); 237 else 238 fprintf(outfile, "<missing argument>"); 239 fprintf(outfile, "%s", i < (nargs - 1) ? "," : ""); 240 } 241 fprintf(outfile, ")\n\t"); 242 } 243