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 "$FreeBSD$"; 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 <signal.h> 49 #include "syscall.h" 50 51 /* 52 * This should probably be in its own file. 53 */ 54 55 struct syscall syscalls[] = { 56 { "readlink", 1, 3, 57 { { String, 0 } , { String | OUT, 1 }, { Int, 2 }}}, 58 { "lseek", 2, 3, 59 { { Int, 0 }, {Quad, 2 }, { Int, 4 }}}, 60 { "mmap", 2, 6, 61 { { Hex, 0 }, {Int, 1}, {Hex, 2}, {Hex, 3}, {Int, 4}, {Quad, 6}}}, 62 { "open", 1, 3, 63 { { String | IN, 0} , { Int, 1}, {Octal, 2}}}, 64 { "linux_open", 1, 3, 65 { { String, 0 }, { Int, 1}, { Octal, 2 }}}, 66 { "close", 1, 1, { { Int, 0 } } }, 67 { "fstat", 1, 2, 68 { { Int, 0}, {Ptr | OUT , 1 }}}, 69 { "stat", 1, 2, 70 { { String | IN, 0 }, { Ptr | OUT, 1 }}}, 71 { "lstat", 1, 2, 72 { { String | IN, 0 }, { Ptr | OUT, 1 }}}, 73 { "linux_newstat", 1, 2, 74 { { String | IN, 0 }, { Ptr | OUT, 1 }}}, 75 { "linux_newfstat", 1, 2, 76 { { Int, 0 }, { Ptr | OUT, 1 }}}, 77 { "write", 1, 3, 78 { { Int, 0}, { Ptr | IN, 1 }, { Int, 2 }}}, 79 { "ioctl", 1, 3, 80 { { Int, 0}, { Ioctl, 1 }, { Hex, 2 }}}, 81 { "break", 1, 1, { { Hex, 0 }}}, 82 { "exit", 0, 1, { { Hex, 0 }}}, 83 { "access", 1, 2, { { String | IN, 0 }, { Int, 1 }}}, 84 { "sigaction", 1, 3, 85 { { Signal, 0 }, { Ptr | IN, 1 }, { Ptr | OUT, 2 }}}, 86 { 0, 0, 0, { { 0, 0 }}}, 87 }; 88 89 char * ioctlname __P((int)); 90 91 /* 92 * If/when the list gets big, it might be desirable to do it 93 * as a hash table or binary search. 94 */ 95 96 struct syscall * 97 get_syscall(const char *name) { 98 struct syscall *sc = syscalls; 99 100 while (sc->name) { 101 if (!strcmp(name, sc->name)) 102 return sc; 103 sc++; 104 } 105 return NULL; 106 } 107 108 /* 109 * get_string 110 * Copy a string from the process. Note that it is 111 * expected to be a C string, but if max is set, it will 112 * only get that much. 113 */ 114 115 char * 116 get_string(int procfd, void *offset, int max) { 117 char *buf; 118 int size, len, c, fd; 119 FILE *p; 120 121 if ((fd = dup(procfd)) == -1) 122 err(1, "dup"); 123 if ((p = fdopen(fd, "r")) == NULL) 124 err(1, "fdopen"); 125 buf = malloc( size = (max ? max : 64 ) ); 126 len = 0; 127 fseek(p, (long)offset, SEEK_SET); 128 while ((c = fgetc(p)) != EOF) { 129 buf[len++] = c; 130 if (c == 0 || len == max) { 131 buf[len] = 0; 132 break; 133 } 134 if (len == size) { 135 char *tmp; 136 tmp = realloc(buf, size+64); 137 if (tmp == NULL) { 138 buf[len] = 0; 139 fclose(p); 140 return buf; 141 } 142 size += 64; 143 buf = tmp; 144 } 145 } 146 fclose(p); 147 return buf; 148 } 149 150 151 /* 152 * Gag. This is really unportable. Multiplication is more portable. 153 * But slower, from the code I saw. 154 */ 155 156 static long long 157 make_quad(unsigned long p1, unsigned long p2) { 158 union { 159 long long ll; 160 unsigned long l[2]; 161 } t; 162 t.l[0] = p1; 163 t.l[1] = p2; 164 return t.ll; 165 } 166 167 168 /* 169 * print_arg 170 * Converts a syscall argument into a string. Said string is 171 * allocated via malloc(), so needs to be free()'d. The file 172 * descriptor is for the process' memory (via /proc), and is used 173 * to get any data (where the argument is a pointer). sc is 174 * a pointer to the syscall description (see above); args is 175 * an array of all of the system call arguments. 176 */ 177 178 char * 179 print_arg(int fd, struct syscall_args *sc, unsigned long *args) { 180 char *tmp = NULL; 181 switch (sc->type & ARG_MASK) { 182 case Hex: 183 tmp = malloc(12); 184 sprintf(tmp, "0x%lx", args[sc->offset]); 185 break; 186 case Octal: 187 tmp = malloc(13); 188 sprintf(tmp, "0%lo", args[sc->offset]); 189 break; 190 case Int: 191 tmp = malloc(12); 192 sprintf(tmp, "%ld", args[sc->offset]); 193 break; 194 case String: 195 { 196 char *tmp2; 197 tmp2 = get_string(fd, (void*)args[sc->offset], 0); 198 tmp = malloc(strlen(tmp2) + 3); 199 sprintf(tmp, "\"%s\"", tmp2); 200 free(tmp2); 201 } 202 break; 203 case Quad: 204 { 205 unsigned long long t; 206 unsigned long l1, l2; 207 l1 = args[sc->offset]; 208 l2 = args[sc->offset+1]; 209 t = make_quad(l1, l2); 210 tmp = malloc(24); 211 sprintf(tmp, "0x%qx", t); 212 break; 213 } 214 case Ptr: 215 tmp = malloc(12); 216 sprintf(tmp, "0x%lx", args[sc->offset]); 217 break; 218 case Ioctl: 219 { 220 char *temp = ioctlname(args[sc->offset]); 221 if (temp) 222 tmp = strdup(temp); 223 else { 224 tmp = malloc(12); 225 sprintf(tmp, "0x%lx", args[sc->offset]); 226 } 227 } 228 break; 229 case Signal: 230 { 231 long sig; 232 233 sig = args[sc->offset]; 234 tmp = malloc(12); 235 if (sig > 0 && sig < NSIG) { 236 int i; 237 sprintf(tmp, "sig%s", sys_signame[sig]); 238 for (i = 0; tmp[i] != '\0'; ++i) 239 tmp[i] = toupper(tmp[i]); 240 } else { 241 sprintf(tmp, "%ld", sig); 242 } 243 } 244 break; 245 } 246 return tmp; 247 } 248 249 /* 250 * print_syscall 251 * Print (to outfile) the system call and its arguments. Note that 252 * nargs is the number of arguments (not the number of words; this is 253 * potentially confusing, I know). 254 */ 255 256 void 257 print_syscall(FILE *outfile, const char *name, int nargs, char **s_args) { 258 int i; 259 fprintf(outfile, "syscall %s(", name); 260 for (i = 0; i < nargs; i++) { 261 if (s_args[i]) 262 fprintf(outfile, "%s", s_args[i]); 263 else 264 fprintf(outfile, "<missing argument>"); 265 fprintf(outfile, "%s", i < (nargs - 1) ? "," : ""); 266 } 267 fprintf(outfile, ")\n\t"); 268 } 269