diff options
Diffstat (limited to 'usr/src/uts/common/os/exec.c')
| -rw-r--r-- | usr/src/uts/common/os/exec.c | 53 |
1 files changed, 51 insertions, 2 deletions
diff --git a/usr/src/uts/common/os/exec.c b/usr/src/uts/common/os/exec.c index 994c034fe0..d421483279 100644 --- a/usr/src/uts/common/os/exec.c +++ b/usr/src/uts/common/os/exec.c @@ -97,6 +97,7 @@ uint_t auxv_hwcap32_2 = 0; /* 32-bit version of auxv_hwcap2 */ #endif #define PSUIDFLAGS (SNOCD|SUGID) +#define RANDOM_LEN 16 /* 16 bytes for AT_RANDOM aux entry */ /* * exece() - system call wrapper around exec_common() @@ -1498,6 +1499,27 @@ stk_add(uarg_t *args, const char *sp, enum uio_seg segflg) return (0); } +/* + * Add a fixed size byte array to the stack (only from kernel space). + */ +static int +stk_byte_add(uarg_t *args, const uint8_t *sp, size_t len) +{ + int error; + + if (STK_AVAIL(args) < sizeof (int)) + return (E2BIG); + *--args->stk_offp = args->stk_strp - args->stk_base; + + if (len > STK_AVAIL(args)) + return (E2BIG); + bcopy(sp, args->stk_strp, len); + + args->stk_strp += len; + + return (0); +} + static int stk_getptr(uarg_t *args, char *src, char **dst) { @@ -1534,6 +1556,9 @@ stk_copyin(execa_t *uap, uarg_t *args, intpdata_t *intp, void **auxvpp) size_t size, pad; char *argv = (char *)uap->argp; char *envp = (char *)uap->envp; + uint32_t rvals; + uint8_t *rtp; + uint8_t rdata[RANDOM_LEN]; /* * Copy interpreter's name and argument to argv[0] and argv[1]. @@ -1604,7 +1629,7 @@ stk_copyin(execa_t *uap, uarg_t *args, intpdata_t *intp, void **auxvpp) /* * Add AT_SUN_PLATFORM, AT_SUN_EXECNAME, AT_SUN_BRANDNAME, and - * AT_SUN_EMULATOR strings to the stack. + * AT_SUN_EMULATOR strings, as well as AT_RANDOM array, to the stack. */ if (auxvpp != NULL && *auxvpp != NULL) { if ((error = stk_add(args, platform, UIO_SYSSPACE)) != 0) @@ -1617,6 +1642,28 @@ stk_copyin(execa_t *uap, uarg_t *args, intpdata_t *intp, void **auxvpp) if (args->emulator != NULL && (error = stk_add(args, args->emulator, UIO_SYSSPACE)) != 0) return (error); + + /* + * For the AT_RANDOM aux vector we provide 16 bytes of random + * data. However, we don't want to depend on + * kcf_rnd_get_pseudo_bytes for early processes, so just jumble + * some bits from hrtime to get some (pseudo)randomness. + */ + rvals = (uint32_t)gethrtime(); + rtp = (uint8_t *)&rvals; + rdata[0] = rdata[11] = *rtp++; + rdata[1] = rdata[15] = *rtp++; + rdata[2] = rdata[9] = *rtp++; + rdata[3] = rdata[12] = *rtp; + + rtp = (uint8_t *)&rvals; + rdata[4] = rdata[8] = ~(*rtp++); + rdata[5] = rdata[14] = ~(*rtp++); + rdata[6] = rdata[13] = ~(*rtp++); + rdata[7] = rdata[10] = ~(*rtp); + + if ((error = stk_byte_add(args, rdata, sizeof (rdata))) != 0) + return (error); } /* @@ -1723,7 +1770,7 @@ stk_copyout(uarg_t *args, char *usrstack, void **auxvpp, user_t *up) /* * Fill in the aux vector now that we know the user stack addresses * for the AT_SUN_PLATFORM, AT_SUN_EXECNAME, AT_SUN_BRANDNAME and - * AT_SUN_EMULATOR strings. + * AT_SUN_EMULATOR strings, as well as the AT_RANDOM array. */ if (auxvpp != NULL && *auxvpp != NULL) { if (args->to_model == DATAMODEL_NATIVE) { @@ -1736,6 +1783,7 @@ stk_copyout(uarg_t *args, char *usrstack, void **auxvpp, user_t *up) if (args->emulator != NULL) ADDAUX(*a, AT_SUN_EMULATOR, (long)&ustrp[*--offp]) + ADDAUX(*a, AT_RANDOM, (long)&ustrp[*--offp]) } else { auxv32_t **a = (auxv32_t **)auxvpp; ADDAUX(*a, @@ -1748,6 +1796,7 @@ stk_copyout(uarg_t *args, char *usrstack, void **auxvpp, user_t *up) if (args->emulator != NULL) ADDAUX(*a, AT_SUN_EMULATOR, (int)(uintptr_t)&ustrp[*--offp]) + ADDAUX(*a, AT_RANDOM, (int)(uintptr_t)&ustrp[*--offp]) } } |