From mboxrd@z Thu Jan 1 00:00:00 1970 Return-Path: Received: by sourceware.org (Postfix, from userid 1944) id C596B3851511; Thu, 27 Oct 2022 14:00:09 +0000 (GMT) DKIM-Filter: OpenDKIM Filter v2.11.0 sourceware.org C596B3851511 DKIM-Signature: v=1; a=rsa-sha256; c=relaxed/relaxed; d=sourceware.org; s=default; t=1666879209; bh=I9lIorNU3l5hJFhD8Fv1r7sqG+/F7MKpqc4p1jCUq5Q=; h=From:To:Subject:Date:From; b=Apg45a29TnWasAEXWDla8rDQxoVHPiy3dBFMhvkg32OU0i9TsZXbwPYGH831EbcrN 78uEaOTsOkeJSyOhyilV3w18mwjOKtV1m6O/aYoOqEqmG5lGZDaYSWDCdj0wbSciH2 N2HjZyOLy6A2EqNdVbc+LFeuu6n+2nq8lXvwbZcU= Content-Type: text/plain; charset="us-ascii" MIME-Version: 1.0 Content-Transfer-Encoding: 7bit From: Szabolcs Nagy To: glibc-cvs@sourceware.org Subject: [glibc/arm/morello/main] TODO(api): cheri: misc: Implement new function getauxptr for CHERI capabilities X-Act-Checkin: glibc X-Git-Author: Carlos Eduardo Seo X-Git-Refname: refs/heads/arm/morello/main X-Git-Oldrev: fac448ae9edb57ad6a8415ecfa6ef5dad61a9d0c X-Git-Newrev: 3386ca6696dbf1578fe605f9b380931052bd7329 Message-Id: <20221027140009.C596B3851511@sourceware.org> Date: Thu, 27 Oct 2022 14:00:09 +0000 (GMT) List-Id: https://sourceware.org/git/gitweb.cgi?p=glibc.git;h=3386ca6696dbf1578fe605f9b380931052bd7329 commit 3386ca6696dbf1578fe605f9b380931052bd7329 Author: Carlos Eduardo Seo Date: Wed May 18 00:52:09 2022 +0000 TODO(api): cheri: misc: Implement new function getauxptr for CHERI capabilities New function to return values from the auxiliary vector as capabilities. This is the same as implemented by other C libraries. TODO: agree about exact semantics across libcs Diff: --- include/sys/auxv.h | 4 ++++ misc/Versions | 3 +++ misc/getauxval.c | 33 +++++++++++++++++++++++++++++++++ misc/sys/auxv.h | 4 ++++ 4 files changed, 44 insertions(+) diff --git a/include/sys/auxv.h b/include/sys/auxv.h index dd0602b08d..0bd40bd835 100644 --- a/include/sys/auxv.h +++ b/include/sys/auxv.h @@ -10,4 +10,8 @@ libc_hidden_proto (__getauxval) _Bool __getauxval2 (unsigned long int type, unsigned long int *result); libc_hidden_proto (__getauxval2) +/* Like getauxval, but for Arm Morello capabilities. */ +extern __typeof (getauxptr) __getauxptr; +libc_hidden_proto (__getauxptr) + #endif /* !_ISOMAC */ diff --git a/misc/Versions b/misc/Versions index d5b348e83a..669a03ffb3 100644 --- a/misc/Versions +++ b/misc/Versions @@ -164,6 +164,9 @@ libc { GLIBC_2.32 { __libc_single_threaded; } + GLIBC_2.36 { + __getauxptr; getauxptr; + } GLIBC_PRIVATE { __madvise; __mktemp; diff --git a/misc/getauxval.c b/misc/getauxval.c index 714ce5bd62..a4625b8596 100644 --- a/misc/getauxval.c +++ b/misc/getauxval.c @@ -20,6 +20,39 @@ #include #include +void * +__getauxptr (unsigned long int type) +{ + /* error if asking for a non-pointer from getauxptr(). This list is not a + perfect enforcement as it currently supports both transitional and draft + ABIs, which have different capability entries. */ + switch (type) { + case AT_ENTRY: + case AT_PHDR: + case AT_BASE: + case AT_SYSINFO_EHDR: + case AT_EXECFN: + case AT_RANDOM: + case AT_PLATFORM: + case AT_CHERI_EXEC_RW_CAP: + case AT_CHERI_EXEC_RX_CAP: + case AT_CHERI_INTERP_RW_CAP: + case AT_CHERI_INTERP_RX_CAP: + case AT_CHERI_SEAL_CAP: + { + ElfW(auxv_t) *p; + for (p = GLRO(dl_auxv); p->a_type != AT_NULL; p++) + if (p->a_type == type) + return (void *) p->a_un.a_val; + } + } + + __set_errno (ENOENT); + return 0; +} +weak_alias (__getauxptr, getauxptr) +libc_hidden_def (__getauxptr) + bool __getauxval2 (unsigned long int type, unsigned long int *result) { diff --git a/misc/sys/auxv.h b/misc/sys/auxv.h index b5ab30ab77..8446aeddd0 100644 --- a/misc/sys/auxv.h +++ b/misc/sys/auxv.h @@ -31,6 +31,10 @@ __BEGIN_DECLS extern unsigned long int getauxval (unsigned long int __type) __THROW; +/* Same as getauxval, but for Arm Morello capabilities. */ +extern void * getauxptr (unsigned long int __type) + __THROW; + __END_DECLS #endif /* sys/auxv.h */