X-Git-Url: https://git.tcpdump.org/libpcap/blobdiff_plain/842012ab4d8188a66a4c03da66f1782ba31dcecb..09b51d326c38ea8e10ce4da09c09d50e08c5aeb8:/extract.h diff --git a/extract.h b/extract.h index face5b7e..33579b11 100644 --- a/extract.h +++ b/extract.h @@ -23,32 +23,115 @@ #include #endif +#include +#include +#include "portability.h" + /* - * Macros to extract possibly-unaligned big-endian integral values. + * If we have versions of GCC or Clang that support an __attribute__ + * to say "if we're building with unsigned behavior sanitization, + * don't complain about undefined behavior in this function", we + * label these functions with that attribute - we *know* it's undefined + * in the C standard, but we *also* know it does what we want with + * the ISA we're targeting and the compiler we're using. + * + * For GCC 4.9.0 and later, we use __attribute__((no_sanitize_undefined)); + * pre-5.0 GCC doesn't have __has_attribute, and I'm not sure whether + * GCC or Clang first had __attribute__((no_sanitize(XXX)). + * + * For Clang, we check for __attribute__((no_sanitize(XXX)) with + * __has_attribute, as there are versions of Clang that support + * __attribute__((no_sanitize("undefined")) but don't support + * __attribute__((no_sanitize_undefined)). + * + * We define this here, rather than in funcattrs.h, because we + * only want it used here, we don't want it to be broadly used. + * (Any printer will get this defined, but this should at least + * make it harder for people to find.) */ -#ifdef LBL_ALIGN +#if defined(__GNUC__) && ((__GNUC__ * 100 + __GNUC_MINOR__) >= 409) +#define UNALIGNED_OK __attribute__((no_sanitize_undefined)) +#elif __has_attribute(no_sanitize) +#define UNALIGNED_OK __attribute__((no_sanitize("undefined"))) +#else +#define UNALIGNED_OK +#endif + +#if (defined(__i386__) || defined(_M_IX86) || defined(__X86__) || defined(__x86_64__) || defined(_M_X64)) || \ + (defined(__m68k__) && (!defined(__mc68000__) && !defined(__mc68010__))) || \ + (defined(__ppc__) || defined(__ppc64__) || defined(_M_PPC) || defined(_ARCH_PPC) || defined(_ARCH_PPC64)) || \ + (defined(__s390__) || defined(__s390x__) || defined(__zarch__)) /* - * The processor doesn't natively handle unaligned loads. + * The processor natively handles unaligned loads, so we can just + * cast the pointer and fetch through it. + * + * XXX - are those all the x86 tests we need? + * XXX - are those the only 68k tests we need not to generated + * unaligned accesses if the target is the 68000 or 68010? + * XXX - are there any tests we don't need, because some definitions are for + * compilers that also predefine the GCC symbols? + * XXX - do we need to test for both 32-bit and 64-bit versions of those + * architectures in all cases? */ -#if defined(__GNUC__) && defined(HAVE___ATTRIBUTE__) && \ +UNALIGNED_OK static inline uint16_t +EXTRACT_BE_U_2(const void *p) +{ + return ((uint16_t)ntohs(*(const uint16_t *)(p))); +} + +UNALIGNED_OK static inline int16_t +EXTRACT_BE_S_2(const void *p) +{ + return ((int16_t)ntohs(*(const int16_t *)(p))); +} + +UNALIGNED_OK static inline uint32_t +EXTRACT_BE_U_4(const void *p) +{ + return ((uint32_t)ntohl(*(const uint32_t *)(p))); +} + +UNALIGNED_OK static inline int32_t +EXTRACT_BE_S_4(const void *p) +{ + return ((int32_t)ntohl(*(const int32_t *)(p))); +} + +UNALIGNED_OK static inline uint64_t +EXTRACT_BE_U_8(const void *p) +{ + return ((uint64_t)(((uint64_t)ntohl(*((const uint32_t *)(p) + 0))) << 32 | + ((uint64_t)ntohl(*((const uint32_t *)(p) + 1))) << 0)); + +} + +UNALIGNED_OK static inline int64_t +EXTRACT_BE_S_8(const void *p) +{ + return ((int64_t)(((int64_t)ntohl(*((const uint32_t *)(p) + 0))) << 32 | + ((uint64_t)ntohl(*((const uint32_t *)(p) + 1))) << 0)); + +} +#elif PCAP_IS_AT_LEAST_GNUC_VERSION(2,0) && \ (defined(__alpha) || defined(__alpha__) || \ defined(__mips) || defined(__mips__)) - /* - * This is a GCC-compatible compiler and we have __attribute__, which - * we assume that mean we have __attribute__((packed)), and this is - * MIPS or Alpha, which has instructions that can help when doing - * unaligned loads. + * This is MIPS or Alpha, which don't natively handle unaligned loads, + * but which have instructions that can help when doing unaligned + * loads, and this is GCC 2.0 or later or a compiler that claims to + * be GCC 2.0 or later, which we assume that mean we have + * __attribute__((packed)), which we can use to convince the compiler + * to generate those instructions. * * Declare packed structures containing a uint16_t and a uint32_t, * cast the pointer to point to one of those, and fetch through it; * the GCC manual doesn't appear to explicitly say that * __attribute__((packed)) causes the compiler to generate unaligned-safe - * code, but it apppears to do so. + * code, but it appears to do so. * * We do this in case the compiler can generate code using those * instructions to do an unaligned load and pass stuff to "ntohs()" or - * "ntohl()", which might be better than than the code to fetch the + * "ntohl()", which might be better than the code to fetch the * bytes one at a time and assemble them. (That might not be the * case on a little-endian platform, such as DEC's MIPS machines and * Alpha machines, where "ntohs()" and "ntohl()" might not be done @@ -88,46 +171,91 @@ typedef struct { uint16_t val; } __attribute__((packed)) unaligned_uint16_t; +typedef struct { + int16_t val; +} __attribute__((packed)) unaligned_int16_t; + typedef struct { uint32_t val; } __attribute__((packed)) unaligned_uint32_t; -static inline uint16_t -EXTRACT_16BITS(const void *p) +typedef struct { + int32_t val; +} __attribute__((packed)) unaligned_int32_t; + +UNALIGNED_OK static inline uint16_t +EXTRACT_BE_U_2(const void *p) { return ((uint16_t)ntohs(((const unaligned_uint16_t *)(p))->val)); } -static inline uint32_t -EXTRACT_32BITS(const void *p) +UNALIGNED_OK static inline int16_t +EXTRACT_BE_S_2(const void *p) +{ + return ((int16_t)ntohs(((const unaligned_int16_t *)(p))->val)); +} + +UNALIGNED_OK static inline uint32_t +EXTRACT_BE_U_4(const void *p) { return ((uint32_t)ntohl(((const unaligned_uint32_t *)(p))->val)); } -static inline uint64_t -EXTRACT_64BITS(const void *p) +UNALIGNED_OK static inline int32_t +EXTRACT_BE_S_4(const void *p) +{ + return ((int32_t)ntohl(((const unaligned_int32_t *)(p))->val)); +} + +UNALIGNED_OK static inline uint64_t +EXTRACT_BE_U_8(const void *p) { - return ((uint64_t)(((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 0)->val)) << 32 | \ + return ((uint64_t)(((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 0)->val)) << 32 | ((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 1)->val)) << 0)); } -#else /* have to do it a byte at a time */ +UNALIGNED_OK static inline int64_t +EXTRACT_BE_S_8(const void *p) +{ + return ((int64_t)(((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 0)->val)) << 32 | + ((uint64_t)ntohl(((const unaligned_uint32_t *)(p) + 1)->val)) << 0)); +} +#else /* - * This isn't a GCC-compatible compiler, we don't have __attribute__, + * This architecture doesn't natively support unaligned loads, and either + * this isn't a GCC-compatible compiler, we don't have __attribute__, * or we do but we don't know of any better way with this instruction * set to do unaligned loads, so do unaligned loads of big-endian * quantities the hard way - fetch the bytes one at a time and * assemble them. + * + * XXX - ARM is a special case. ARMv1 through ARMv5 didn't suppory + * unaligned loads; ARMv6 and later support it *but* have a bit in + * the system control register that the OS can set and that causes + * unaligned loads to fault rather than succeeding. + * + * At least some OSes may set that flag, so we do *not* treat ARM + * as supporting unaligned loads. If your OS supports them on ARM, + * and you want to use them, please update the tests in the #if above + * to check for ARM *and* for your OS. */ -#define EXTRACT_16BITS(p) \ +#define EXTRACT_BE_U_2(p) \ ((uint16_t)(((uint16_t)(*((const uint8_t *)(p) + 0)) << 8) | \ ((uint16_t)(*((const uint8_t *)(p) + 1)) << 0))) -#define EXTRACT_32BITS(p) \ +#define EXTRACT_BE_S_2(p) \ + ((int16_t)(((uint16_t)(*((const uint8_t *)(p) + 0)) << 8) | \ + ((uint16_t)(*((const uint8_t *)(p) + 1)) << 0))) +#define EXTRACT_BE_U_4(p) \ ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 24) | \ ((uint32_t)(*((const uint8_t *)(p) + 1)) << 16) | \ ((uint32_t)(*((const uint8_t *)(p) + 2)) << 8) | \ ((uint32_t)(*((const uint8_t *)(p) + 3)) << 0))) -#define EXTRACT_64BITS(p) \ +#define EXTRACT_BE_S_4(p) \ + ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 24) | \ + ((uint32_t)(*((const uint8_t *)(p) + 1)) << 16) | \ + ((uint32_t)(*((const uint8_t *)(p) + 2)) << 8) | \ + ((uint32_t)(*((const uint8_t *)(p) + 3)) << 0))) +#define EXTRACT_BE_U_8(p) \ ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 56) | \ ((uint64_t)(*((const uint8_t *)(p) + 1)) << 48) | \ ((uint64_t)(*((const uint8_t *)(p) + 2)) << 40) | \ @@ -136,47 +264,67 @@ EXTRACT_64BITS(const void *p) ((uint64_t)(*((const uint8_t *)(p) + 5)) << 16) | \ ((uint64_t)(*((const uint8_t *)(p) + 6)) << 8) | \ ((uint64_t)(*((const uint8_t *)(p) + 7)) << 0))) -#endif /* must special-case unaligned accesses */ -#else /* LBL_ALIGN */ +#define EXTRACT_BE_S_8(p) \ + ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 56) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 48) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 40) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 5)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 6)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 7)) << 0))) + /* - * The processor natively handles unaligned loads, so we can just - * cast the pointer and fetch through it. + * Extract an IPv4 address, which is in network byte order, and not + * necessarily aligned, and provide the result in host byte order. */ -static inline uint16_t -EXTRACT_16BITS(const void *p) -{ - return ((uint16_t)ntohs(*(const uint16_t *)(p))); -} - -static inline uint32_t -EXTRACT_32BITS(const void *p) -{ - return ((uint32_t)ntohl(*(const uint32_t *)(p))); -} - -static inline uint64_t -EXTRACT_64BITS(const void *p) -{ - return ((uint64_t)(((uint64_t)ntohl(*((const uint32_t *)(p) + 0))) << 32 | \ - ((uint64_t)ntohl(*((const uint32_t *)(p) + 1))) << 0)); - -} - -#endif /* LBL_ALIGN */ +#define EXTRACT_IPV4_TO_HOST_ORDER(p) \ + ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 24) | \ + ((uint32_t)(*((const uint8_t *)(p) + 1)) << 16) | \ + ((uint32_t)(*((const uint8_t *)(p) + 2)) << 8) | \ + ((uint32_t)(*((const uint8_t *)(p) + 3)) << 0))) +#endif /* unaligned access checks */ -#define EXTRACT_24BITS(p) \ +/* + * Non-power-of-2 sizes. + */ +#define EXTRACT_BE_U_3(p) \ ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 16) | \ ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \ ((uint32_t)(*((const uint8_t *)(p) + 2)) << 0))) -#define EXTRACT_40BITS(p) \ +#define EXTRACT_BE_S_3(p) \ + (((*((const uint8_t *)(p) + 0)) & 0x80) ? \ + ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 0)) << 16) | \ + ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \ + ((uint32_t)(*((const uint8_t *)(p) + 2)) << 0))) : \ + ((int32_t)(0xFF000000U | \ + ((uint32_t)(*((const uint8_t *)(p) + 0)) << 16) | \ + ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \ + ((uint32_t)(*((const uint8_t *)(p) + 2)) << 0)))) + +#define EXTRACT_BE_U_5(p) \ ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 32) | \ ((uint64_t)(*((const uint8_t *)(p) + 1)) << 24) | \ ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \ ((uint64_t)(*((const uint8_t *)(p) + 3)) << 8) | \ ((uint64_t)(*((const uint8_t *)(p) + 4)) << 0))) -#define EXTRACT_48BITS(p) \ +#define EXTRACT_BE_S_5(p) \ + (((*((const uint8_t *)(p) + 0)) & 0x80) ? \ + ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 0))) : \ + ((int64_t)(INT64_T_CONSTANT(0xFFFFFF0000000000U) | \ + ((uint64_t)(*((const uint8_t *)(p) + 0)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 0)))) + +#define EXTRACT_BE_U_6(p) \ ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 40) | \ ((uint64_t)(*((const uint8_t *)(p) + 1)) << 32) | \ ((uint64_t)(*((const uint8_t *)(p) + 2)) << 24) | \ @@ -184,7 +332,23 @@ EXTRACT_64BITS(const void *p) ((uint64_t)(*((const uint8_t *)(p) + 4)) << 8) | \ ((uint64_t)(*((const uint8_t *)(p) + 5)) << 0))) -#define EXTRACT_56BITS(p) \ +#define EXTRACT_BE_S_6(p) \ + (((*((const uint8_t *)(p) + 0)) & 0x80) ? \ + ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 40) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 5)) << 0))) : \ + ((int64_t)(INT64_T_CONSTANT(0xFFFFFFFF00000000U) | \ + ((uint64_t)(*((const uint8_t *)(p) + 0)) << 40) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 5)) << 0)))) + +#define EXTRACT_BE_U_7(p) \ ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 48) | \ ((uint64_t)(*((const uint8_t *)(p) + 1)) << 40) | \ ((uint64_t)(*((const uint8_t *)(p) + 2)) << 32) | \ @@ -193,24 +357,53 @@ EXTRACT_64BITS(const void *p) ((uint64_t)(*((const uint8_t *)(p) + 5)) << 8) | \ ((uint64_t)(*((const uint8_t *)(p) + 6)) << 0))) +#define EXTRACT_BE_S_7(p) \ + (((*((const uint8_t *)(p) + 0)) & 0x80) ? \ + ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 0)) << 48) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 40) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 5)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 6)) << 0))) : \ + ((int64_t)(INT64_T_CONSTANT(0xFFFFFFFFFF000000U) | \ + ((uint64_t)(*((const uint8_t *)(p) + 0)) << 48) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 40) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 5)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 6)) << 0)))) + /* * Macros to extract possibly-unaligned little-endian integral values. * XXX - do loads on little-endian machines that support unaligned loads? */ -#define EXTRACT_LE_8BITS(p) (*(p)) -#define EXTRACT_LE_16BITS(p) \ +#define EXTRACT_LE_U_2(p) \ ((uint16_t)(((uint16_t)(*((const uint8_t *)(p) + 1)) << 8) | \ ((uint16_t)(*((const uint8_t *)(p) + 0)) << 0))) -#define EXTRACT_LE_32BITS(p) \ +#define EXTRACT_LE_S_2(p) \ + ((int16_t)(((uint16_t)(*((const uint8_t *)(p) + 1)) << 8) | \ + ((uint16_t)(*((const uint8_t *)(p) + 0)) << 0))) +#define EXTRACT_LE_U_4(p) \ ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 3)) << 24) | \ ((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \ ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \ ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0))) -#define EXTRACT_LE_24BITS(p) \ +#define EXTRACT_LE_S_4(p) \ + ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 3)) << 24) | \ + ((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \ + ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \ + ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0))) +#define EXTRACT_LE_U_3(p) \ ((uint32_t)(((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \ ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \ ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0))) -#define EXTRACT_LE_64BITS(p) \ +#define EXTRACT_LE_S_3(p) \ + ((int32_t)(((uint32_t)(*((const uint8_t *)(p) + 2)) << 16) | \ + ((uint32_t)(*((const uint8_t *)(p) + 1)) << 8) | \ + ((uint32_t)(*((const uint8_t *)(p) + 0)) << 0))) +#define EXTRACT_LE_U_8(p) \ ((uint64_t)(((uint64_t)(*((const uint8_t *)(p) + 7)) << 56) | \ ((uint64_t)(*((const uint8_t *)(p) + 6)) << 48) | \ ((uint64_t)(*((const uint8_t *)(p) + 5)) << 40) | \ @@ -219,3 +412,12 @@ EXTRACT_64BITS(const void *p) ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \ ((uint64_t)(*((const uint8_t *)(p) + 1)) << 8) | \ ((uint64_t)(*((const uint8_t *)(p) + 0)) << 0))) +#define EXTRACT_LE_S_8(p) \ + ((int64_t)(((uint64_t)(*((const uint8_t *)(p) + 7)) << 56) | \ + ((uint64_t)(*((const uint8_t *)(p) + 6)) << 48) | \ + ((uint64_t)(*((const uint8_t *)(p) + 5)) << 40) | \ + ((uint64_t)(*((const uint8_t *)(p) + 4)) << 32) | \ + ((uint64_t)(*((const uint8_t *)(p) + 3)) << 24) | \ + ((uint64_t)(*((const uint8_t *)(p) + 2)) << 16) | \ + ((uint64_t)(*((const uint8_t *)(p) + 1)) << 8) | \ + ((uint64_t)(*((const uint8_t *)(p) + 0)) << 0)))