commit e428ae4bbea17cab194a8c3acd99bc44614b0901 Author: Yawning Angel <yawning@schwanenlied.me> Date: Sat Mar 28 13:55:55 2015 +0000 Support certain Linux specific syscalls. This adds support for the following non-portable Linux-isms: * gettid(2) * getrandom(2) * futex(2) The futex(2) support assumes a semi-modern kernel (>= 2.6.7) as the futex system call had an extra argument added at that time. Signed-off-by: Yawning Angel <yawning@schwanenlied.me> --- src/common/compat.h | 12 ++++++++++ src/lib/syscall.c | 61 +++++++++++++++++++++++++++++++++++++++++++++++++++ 2 files changed, 73 insertions(+) diff --git a/src/common/compat.h b/src/common/compat.h index 766b1fd..6fca641 100644 --- a/src/common/compat.h +++ b/src/common/compat.h @@ -84,6 +84,15 @@ void tsocks_mutex_unlock(tsocks_mutex_t *m); #ifndef __NR_recvmsg #define __NR_recvmsg -9 #endif +#ifndef __NR_gettid +#define __NR_gettid -10 +#endif +#ifndef __NR_getrandom +#define __NR_getrandom -11 +#endif +#ifndef __NR_futex +#define __NR_futex -12 +#endif #define TSOCKS_NR_SOCKET __NR_socket #define TSOCKS_NR_CONNECT __NR_connect @@ -94,6 +103,9 @@ void tsocks_mutex_unlock(tsocks_mutex_t *m); #define TSOCKS_NR_GETPEERNAME __NR_getpeername #define TSOCKS_NR_LISTEN __NR_listen #define TSOCKS_NR_RECVMSG __NR_recvmsg +#define TSOCKS_NR_GETTID __NR_gettid +#define TSOCKS_NR_GETRANDOM __NR_getrandom +#define TSOCKS_NR_FUTEX __NR_futex #endif /* __linux__ */ diff --git a/src/lib/syscall.c b/src/lib/syscall.c index ec10000..52ee4c2 100644 --- a/src/lib/syscall.c +++ b/src/lib/syscall.c @@ -164,6 +164,56 @@ static LIBC_RECVMSG_RET_TYPE handle_recvmsg(va_list args) return tsocks_recvmsg(sockfd, msg, flags); } +#if defined(__linux__) +/* + * Handle gettid(2) syscall. + */ +static LIBC_SYSCALL_RET_TYPE handle_gettid(void) +{ + return tsocks_libc_syscall(TSOCKS_NR_GETTID); +} + +/* + * Handle getrandom(2) syscall. + */ +static LIBC_SYSCALL_RET_TYPE handle_getrandom(va_list args) +{ + void *buf; + size_t buflen; + unsigned int flags; + + buf = va_arg(args, __typeof__(buf)); + buflen = va_arg(args, __typeof__(buflen)); + flags = va_arg(args, __typeof__(flags)); + + return tsocks_libc_syscall(TSOCKS_NR_GETRANDOM, buf, buflen, flags); +} + +/* + * Handle futex(2) syscall. + */ +static LIBC_SYSCALL_RET_TYPE handle_futex(va_list args) +{ + /* This assumes Linux 2.6.7 or later, as that is when 'val3' was + * added to futex(2). Kernel versions prior to that are what I + * would consider historic. + */ + const struct timespec *timeout; + int *uaddr, *uaddr2; + int op, val, val3; + + uaddr = va_arg(args, __typeof__(uaddr)); + op = va_arg(args, __typeof__(op)); + val = va_arg(args, __typeof__(val)); + timeout = va_arg(args, __typeof__(timeout)); + uaddr2 = va_arg(args, __typeof__(uaddr2)); + val3 = va_arg(args, __typeof__(val3)); + + return tsocks_libc_syscall(TSOCKS_NR_FUTEX, uaddr, op, val, timeout, + uaddr2, val3); +} +#endif /* __linux__ */ + /* * Torsocks call for syscall(2) */ @@ -228,6 +278,17 @@ LIBC_SYSCALL_RET_TYPE tsocks_syscall(long int number, va_list args) case TSOCKS_NR_RECVMSG: ret = handle_recvmsg(args); break; +#if defined(__linux__) + case TSOCKS_NR_GETTID: + ret = handle_gettid(); + break; + case TSOCKS_NR_GETRANDOM: + ret = handle_getrandom(args); + break; + case TSOCKS_NR_FUTEX: + ret = handle_futex(args); + break; +#endif /* __linux__ */ default: /* * Because of the design of syscall(), we can't pass a va_list to it so