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 33static const char rcsid[] =
| 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 33static const char rcsid[] =
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35#endif /* not lint */ 36 37/* 38 * FreeBSD/amd64-specific system call handling. This is probably the most 39 * complex part of the entire truss program, although I've got lots of 40 * it handled relatively cleanly now. The system call names are generated 41 * automatically, thanks to /usr/src/sys/kern/syscalls.master. The 42 * names used for the various structures are confusing, I sadly admit. 43 */ 44 45#include <sys/types.h> 46#include <sys/ptrace.h> 47#include <sys/syscall.h> 48 49#include <machine/reg.h> 50#include <machine/psl.h> 51 52#include <errno.h> 53#include <fcntl.h> 54#include <signal.h> 55#include <stdio.h> 56#include <stdlib.h> 57#include <string.h> 58#include <time.h> 59#include <unistd.h> 60 61#include "truss.h" 62#include "syscall.h" 63#include "extern.h" 64 65static int cpid = -1; 66 67#include "syscalls.h" 68 69static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]); 70 71/* 72 * This is what this particular file uses to keep track of a system call. 73 * It is probably not quite sufficient -- I can probably use the same 74 * structure for the various syscall personalities, and I also probably 75 * need to nest system calls (for signal handlers). 76 * 77 * 'struct syscall' describes the system call; it may be NULL, however, 78 * if we don't know about this particular system call yet. 79 */ 80static struct freebsd_syscall { 81 struct syscall *sc; 82 const char *name; 83 int number; 84 unsigned long *args; 85 int nargs; /* number of arguments -- *not* number of words! */ 86 char **s_args; /* the printable arguments */ 87} fsc; 88 89/* Clear up and free parts of the fsc structure. */ 90static __inline void 91clear_fsc(void) { 92 if (fsc.args) { 93 free(fsc.args); 94 } 95 if (fsc.s_args) { 96 int i; 97 for (i = 0; i < fsc.nargs; i++) 98 if (fsc.s_args[i]) 99 free(fsc.s_args[i]); 100 free(fsc.s_args); 101 } 102 memset(&fsc, 0, sizeof(fsc)); 103} 104 105/* 106 * Called when a process has entered a system call. nargs is the 107 * number of words, not number of arguments (a necessary distinction 108 * in some cases). Note that if the STOPEVENT() code in amd64/amd64/trap.c 109 * is ever changed these functions need to keep up. 110 */ 111 112void 113amd64_syscall_entry(struct trussinfo *trussinfo, int nargs) { 114 struct reg regs; 115 int syscall_num; 116 int i, reg; 117 struct syscall *sc; 118 119 cpid = trussinfo->curthread->tid; 120 121 clear_fsc(); 122 if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) 123 { 124 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); 125 return; 126 } 127 128 /* 129 * FreeBSD has two special kinds of system call redirctions -- 130 * SYS_syscall, and SYS___syscall. The former is the old syscall() 131 * routine, basicly; the latter is for quad-aligned arguments. 132 */ 133 reg = 0; 134 syscall_num = regs.r_rax; 135 switch (syscall_num) { 136 case SYS_syscall: 137 case SYS___syscall: 138 syscall_num = regs.r_rdi; 139 reg++; 140 break; 141 } 142 143 fsc.number = syscall_num; 144 fsc.name = 145 (syscall_num < 0 || syscall_num >= nsyscalls) ? NULL : syscallnames[syscall_num]; 146 if (!fsc.name) { 147 fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n", syscall_num); 148 } 149 150 if (fsc.name && (trussinfo->flags & FOLLOWFORKS) 151 && ((!strcmp(fsc.name, "fork") 152 || !strcmp(fsc.name, "rfork") 153 || !strcmp(fsc.name, "vfork")))) 154 { 155 trussinfo->curthread->in_fork = 1; 156 } 157 158 if (nargs == 0) 159 return; 160 161 fsc.args = malloc((1+nargs) * sizeof(unsigned long)); 162 for (i = 0; i < nargs && reg < 6; i++, reg++) { 163 switch (reg) { 164 case 0: fsc.args[i] = regs.r_rdi; break; 165 case 1: fsc.args[i] = regs.r_rsi; break; 166 case 2: fsc.args[i] = regs.r_rdx; break; 167 case 3: fsc.args[i] = regs.r_rcx; break; 168 case 4: fsc.args[i] = regs.r_r8; break; 169 case 5: fsc.args[i] = regs.r_r9; break; 170 } 171 } 172 if (nargs > i) { 173 struct ptrace_io_desc iorequest; 174 iorequest.piod_op = PIOD_READ_D; 175 iorequest.piod_offs = (void *)(regs.r_rsp + sizeof(register_t)); 176 iorequest.piod_addr = &fsc.args[i]; 177 iorequest.piod_len = (nargs - i) * sizeof(register_t); 178 ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0); 179 if (iorequest.piod_len == 0) 180 return; 181 } 182 183 sc = get_syscall(fsc.name); 184 if (sc) { 185 fsc.nargs = sc->nargs; 186 } else { 187#if DEBUG 188 fprintf(trussinfo->outfile, "unknown syscall %s -- setting args to %d\n", 189 fsc.name, nargs); 190#endif 191 fsc.nargs = nargs; 192 } 193 194 fsc.s_args = calloc(1, (1+fsc.nargs) * sizeof(char*)); 195 fsc.sc = sc; 196 197 /* 198 * At this point, we set up the system call arguments. 199 * We ignore any OUT ones, however -- those are arguments that 200 * are set by the system call, and so are probably meaningless 201 * now. This doesn't currently support arguments that are 202 * passed in *and* out, however. 203 */ 204 205 if (fsc.name) { 206 207#if DEBUG 208 fprintf(stderr, "syscall %s(", fsc.name); 209#endif 210 for (i = 0; i < fsc.nargs; i++) { 211#if DEBUG 212 fprintf(stderr, "0x%lx%s", 213 sc 214 ? fsc.args[sc->args[i].offset] 215 : fsc.args[i], 216 i < (fsc.nargs - 1) ? "," : ""); 217#endif 218 if (sc && !(sc->args[i].type & OUT)) { 219 fsc.s_args[i] = print_arg(&sc->args[i], fsc.args, 0, trussinfo); 220 } 221 } 222#if DEBUG 223 fprintf(stderr, ")\n"); 224#endif 225 } 226 227#if DEBUG 228 fprintf(trussinfo->outfile, "\n"); 229#endif 230 231 if (fsc.name != NULL && 232 (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) { 233 234 /* XXX 235 * This could be done in a more general 236 * manner but it still wouldn't be very pretty. 237 */ 238 if (!strcmp(fsc.name, "execve")) { 239 if ((trussinfo->flags & EXECVEARGS) == 0) 240 if (fsc.s_args[1]) { 241 free(fsc.s_args[1]); 242 fsc.s_args[1] = NULL; 243 } 244 if ((trussinfo->flags & EXECVEENVS) == 0) 245 if (fsc.s_args[2]) { 246 free(fsc.s_args[2]); 247 fsc.s_args[2] = NULL; 248 } 249 } 250 251 } 252 253 return; 254} 255 256/* 257 * And when the system call is done, we handle it here. 258 * Currently, no attempt is made to ensure that the system calls 259 * match -- this needs to be fixed (and is, in fact, why S_SCX includes 260 * the sytem call number instead of, say, an error status). 261 */ 262 263long 264amd64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused) 265{ 266 struct reg regs; 267 long retval; 268 int i; 269 int errorp; 270 struct syscall *sc; 271 272 if (fsc.name == NULL) 273 return (-1); 274 275 cpid = trussinfo->curthread->tid; 276 277 if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) 278 { 279 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); 280 return (-1); 281 } 282 retval = regs.r_rax; 283 errorp = !!(regs.r_rflags & PSL_C); 284 285 /* 286 * This code, while simpler than the initial versions I used, could 287 * stand some significant cleaning. 288 */ 289 290 sc = fsc.sc; 291 if (!sc) { 292 for (i = 0; i < fsc.nargs; i++) 293 asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]); 294 } else { 295 /* 296 * Here, we only look for arguments that have OUT masked in -- 297 * otherwise, they were handled in the syscall_entry function. 298 */ 299 for (i = 0; i < sc->nargs; i++) { 300 char *temp; 301 if (sc->args[i].type & OUT) { 302 /* 303 * If an error occurred, than don't bothe getting the data; 304 * it may not be valid. 305 */ 306 if (errorp) 307 asprintf(&temp, "0x%lx", fsc.args[sc->args[i].offset]); 308 else 309 temp = print_arg(&sc->args[i], fsc.args, retval, trussinfo); 310 fsc.s_args[i] = temp; 311 } 312 } 313 } 314 315 if (fsc.name != NULL && 316 (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) { 317 trussinfo->curthread->in_syscall = 1; 318 } 319 320 /* 321 * It would probably be a good idea to merge the error handling, 322 * but that complicates things considerably. 323 */ 324 325 print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp, 326 retval, fsc.sc); 327 clear_fsc(); 328 329 return (retval); 330}
| 35#endif /* not lint */ 36 37/* 38 * FreeBSD/amd64-specific system call handling. This is probably the most 39 * complex part of the entire truss program, although I've got lots of 40 * it handled relatively cleanly now. The system call names are generated 41 * automatically, thanks to /usr/src/sys/kern/syscalls.master. The 42 * names used for the various structures are confusing, I sadly admit. 43 */ 44 45#include <sys/types.h> 46#include <sys/ptrace.h> 47#include <sys/syscall.h> 48 49#include <machine/reg.h> 50#include <machine/psl.h> 51 52#include <errno.h> 53#include <fcntl.h> 54#include <signal.h> 55#include <stdio.h> 56#include <stdlib.h> 57#include <string.h> 58#include <time.h> 59#include <unistd.h> 60 61#include "truss.h" 62#include "syscall.h" 63#include "extern.h" 64 65static int cpid = -1; 66 67#include "syscalls.h" 68 69static int nsyscalls = sizeof(syscallnames) / sizeof(syscallnames[0]); 70 71/* 72 * This is what this particular file uses to keep track of a system call. 73 * It is probably not quite sufficient -- I can probably use the same 74 * structure for the various syscall personalities, and I also probably 75 * need to nest system calls (for signal handlers). 76 * 77 * 'struct syscall' describes the system call; it may be NULL, however, 78 * if we don't know about this particular system call yet. 79 */ 80static struct freebsd_syscall { 81 struct syscall *sc; 82 const char *name; 83 int number; 84 unsigned long *args; 85 int nargs; /* number of arguments -- *not* number of words! */ 86 char **s_args; /* the printable arguments */ 87} fsc; 88 89/* Clear up and free parts of the fsc structure. */ 90static __inline void 91clear_fsc(void) { 92 if (fsc.args) { 93 free(fsc.args); 94 } 95 if (fsc.s_args) { 96 int i; 97 for (i = 0; i < fsc.nargs; i++) 98 if (fsc.s_args[i]) 99 free(fsc.s_args[i]); 100 free(fsc.s_args); 101 } 102 memset(&fsc, 0, sizeof(fsc)); 103} 104 105/* 106 * Called when a process has entered a system call. nargs is the 107 * number of words, not number of arguments (a necessary distinction 108 * in some cases). Note that if the STOPEVENT() code in amd64/amd64/trap.c 109 * is ever changed these functions need to keep up. 110 */ 111 112void 113amd64_syscall_entry(struct trussinfo *trussinfo, int nargs) { 114 struct reg regs; 115 int syscall_num; 116 int i, reg; 117 struct syscall *sc; 118 119 cpid = trussinfo->curthread->tid; 120 121 clear_fsc(); 122 if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) 123 { 124 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); 125 return; 126 } 127 128 /* 129 * FreeBSD has two special kinds of system call redirctions -- 130 * SYS_syscall, and SYS___syscall. The former is the old syscall() 131 * routine, basicly; the latter is for quad-aligned arguments. 132 */ 133 reg = 0; 134 syscall_num = regs.r_rax; 135 switch (syscall_num) { 136 case SYS_syscall: 137 case SYS___syscall: 138 syscall_num = regs.r_rdi; 139 reg++; 140 break; 141 } 142 143 fsc.number = syscall_num; 144 fsc.name = 145 (syscall_num < 0 || syscall_num >= nsyscalls) ? NULL : syscallnames[syscall_num]; 146 if (!fsc.name) { 147 fprintf(trussinfo->outfile, "-- UNKNOWN SYSCALL %d --\n", syscall_num); 148 } 149 150 if (fsc.name && (trussinfo->flags & FOLLOWFORKS) 151 && ((!strcmp(fsc.name, "fork") 152 || !strcmp(fsc.name, "rfork") 153 || !strcmp(fsc.name, "vfork")))) 154 { 155 trussinfo->curthread->in_fork = 1; 156 } 157 158 if (nargs == 0) 159 return; 160 161 fsc.args = malloc((1+nargs) * sizeof(unsigned long)); 162 for (i = 0; i < nargs && reg < 6; i++, reg++) { 163 switch (reg) { 164 case 0: fsc.args[i] = regs.r_rdi; break; 165 case 1: fsc.args[i] = regs.r_rsi; break; 166 case 2: fsc.args[i] = regs.r_rdx; break; 167 case 3: fsc.args[i] = regs.r_rcx; break; 168 case 4: fsc.args[i] = regs.r_r8; break; 169 case 5: fsc.args[i] = regs.r_r9; break; 170 } 171 } 172 if (nargs > i) { 173 struct ptrace_io_desc iorequest; 174 iorequest.piod_op = PIOD_READ_D; 175 iorequest.piod_offs = (void *)(regs.r_rsp + sizeof(register_t)); 176 iorequest.piod_addr = &fsc.args[i]; 177 iorequest.piod_len = (nargs - i) * sizeof(register_t); 178 ptrace(PT_IO, cpid, (caddr_t)&iorequest, 0); 179 if (iorequest.piod_len == 0) 180 return; 181 } 182 183 sc = get_syscall(fsc.name); 184 if (sc) { 185 fsc.nargs = sc->nargs; 186 } else { 187#if DEBUG 188 fprintf(trussinfo->outfile, "unknown syscall %s -- setting args to %d\n", 189 fsc.name, nargs); 190#endif 191 fsc.nargs = nargs; 192 } 193 194 fsc.s_args = calloc(1, (1+fsc.nargs) * sizeof(char*)); 195 fsc.sc = sc; 196 197 /* 198 * At this point, we set up the system call arguments. 199 * We ignore any OUT ones, however -- those are arguments that 200 * are set by the system call, and so are probably meaningless 201 * now. This doesn't currently support arguments that are 202 * passed in *and* out, however. 203 */ 204 205 if (fsc.name) { 206 207#if DEBUG 208 fprintf(stderr, "syscall %s(", fsc.name); 209#endif 210 for (i = 0; i < fsc.nargs; i++) { 211#if DEBUG 212 fprintf(stderr, "0x%lx%s", 213 sc 214 ? fsc.args[sc->args[i].offset] 215 : fsc.args[i], 216 i < (fsc.nargs - 1) ? "," : ""); 217#endif 218 if (sc && !(sc->args[i].type & OUT)) { 219 fsc.s_args[i] = print_arg(&sc->args[i], fsc.args, 0, trussinfo); 220 } 221 } 222#if DEBUG 223 fprintf(stderr, ")\n"); 224#endif 225 } 226 227#if DEBUG 228 fprintf(trussinfo->outfile, "\n"); 229#endif 230 231 if (fsc.name != NULL && 232 (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) { 233 234 /* XXX 235 * This could be done in a more general 236 * manner but it still wouldn't be very pretty. 237 */ 238 if (!strcmp(fsc.name, "execve")) { 239 if ((trussinfo->flags & EXECVEARGS) == 0) 240 if (fsc.s_args[1]) { 241 free(fsc.s_args[1]); 242 fsc.s_args[1] = NULL; 243 } 244 if ((trussinfo->flags & EXECVEENVS) == 0) 245 if (fsc.s_args[2]) { 246 free(fsc.s_args[2]); 247 fsc.s_args[2] = NULL; 248 } 249 } 250 251 } 252 253 return; 254} 255 256/* 257 * And when the system call is done, we handle it here. 258 * Currently, no attempt is made to ensure that the system calls 259 * match -- this needs to be fixed (and is, in fact, why S_SCX includes 260 * the sytem call number instead of, say, an error status). 261 */ 262 263long 264amd64_syscall_exit(struct trussinfo *trussinfo, int syscall_num __unused) 265{ 266 struct reg regs; 267 long retval; 268 int i; 269 int errorp; 270 struct syscall *sc; 271 272 if (fsc.name == NULL) 273 return (-1); 274 275 cpid = trussinfo->curthread->tid; 276 277 if (ptrace(PT_GETREGS, cpid, (caddr_t)®s, 0) < 0) 278 { 279 fprintf(trussinfo->outfile, "-- CANNOT READ REGISTERS --\n"); 280 return (-1); 281 } 282 retval = regs.r_rax; 283 errorp = !!(regs.r_rflags & PSL_C); 284 285 /* 286 * This code, while simpler than the initial versions I used, could 287 * stand some significant cleaning. 288 */ 289 290 sc = fsc.sc; 291 if (!sc) { 292 for (i = 0; i < fsc.nargs; i++) 293 asprintf(&fsc.s_args[i], "0x%lx", fsc.args[i]); 294 } else { 295 /* 296 * Here, we only look for arguments that have OUT masked in -- 297 * otherwise, they were handled in the syscall_entry function. 298 */ 299 for (i = 0; i < sc->nargs; i++) { 300 char *temp; 301 if (sc->args[i].type & OUT) { 302 /* 303 * If an error occurred, than don't bothe getting the data; 304 * it may not be valid. 305 */ 306 if (errorp) 307 asprintf(&temp, "0x%lx", fsc.args[sc->args[i].offset]); 308 else 309 temp = print_arg(&sc->args[i], fsc.args, retval, trussinfo); 310 fsc.s_args[i] = temp; 311 } 312 } 313 } 314 315 if (fsc.name != NULL && 316 (!strcmp(fsc.name, "execve") || !strcmp(fsc.name, "exit"))) { 317 trussinfo->curthread->in_syscall = 1; 318 } 319 320 /* 321 * It would probably be a good idea to merge the error handling, 322 * but that complicates things considerably. 323 */ 324 325 print_syscall_ret(trussinfo, fsc.name, fsc.nargs, fsc.s_args, errorp, 326 retval, fsc.sc); 327 clear_fsc(); 328 329 return (retval); 330}
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