From cf5748cc892f78c004359ed321bf72bc8e3772ac Mon Sep 17 00:00:00 2001 From: Denys Vlasenko Date: Fri, 7 Jul 2017 16:00:07 +0200 Subject: [PATCH] setpriv: code shrink, and grouping capability code together function old new delta static.versions - 3 +3 getcaps 174 149 -25 Signed-off-by: Denys Vlasenko --- util-linux/setpriv.c | 187 +++++++++++++++++++++---------------------- 1 file changed, 91 insertions(+), 96 deletions(-) diff --git a/util-linux/setpriv.c b/util-linux/setpriv.c index 8d9c218a3..dc83549ba 100644 --- a/util-linux/setpriv.c +++ b/util-linux/setpriv.c @@ -124,7 +124,7 @@ struct caps { int u32s; }; -#if ENABLE_FEATURE_SETPRIV_CAPABILITY_NAMES +# if ENABLE_FEATURE_SETPRIV_CAPABILITY_NAMES static const char *const capabilities[] = { "chown", "dac_override", @@ -165,17 +165,14 @@ static const char *const capabilities[] = { "block_suspend", "audit_read", }; -#endif /* FEATURE_SETPRIV_CAPABILITY_NAMES */ - -#endif /* FEATURE_SETPRIV_CAPABILITIES */ +# endif /* FEATURE_SETPRIV_CAPABILITY_NAMES */ -#if ENABLE_FEATURE_SETPRIV_CAPABILITIES static void getcaps(struct caps *caps) { - int versions[] = { - _LINUX_CAPABILITY_U32S_3, - _LINUX_CAPABILITY_U32S_2, - _LINUX_CAPABILITY_U32S_1, + static const uint8_t versions[] = { + _LINUX_CAPABILITY_U32S_3, /* = 2 (fits into byte) */ + _LINUX_CAPABILITY_U32S_2, /* = 2 */ + _LINUX_CAPABILITY_U32S_1, /* = 1 */ }; int i; @@ -206,6 +203,91 @@ static void getcaps(struct caps *caps) if (capget(&caps->header, caps->data) < 0) bb_simple_perror_msg_and_die("capget"); } + +static void parse_cap(unsigned long *index, const char *cap) +{ + unsigned long i; + + switch (cap[0]) { + case '-': + break; + case '+': + break; + default: + bb_error_msg_and_die("invalid capability '%s'", cap); + break; + } + + cap++; + if ((sscanf(cap, "cap_%lu", &i)) == 1) { + if (!cap_valid(i)) + bb_error_msg_and_die("unsupported capability '%s'", cap); + *index = i; + return; + } + +# if ENABLE_FEATURE_SETPRIV_CAPABILITY_NAMES + for (i = 0; i < ARRAY_SIZE(capabilities); i++) { + if (strcmp(capabilities[i], cap) != 0) + continue; + + if (!cap_valid(i)) + bb_error_msg_and_die("unsupported capability '%s'", cap); + *index = i; + return; + } +# endif + + bb_error_msg_and_die("unknown capability '%s'", cap); +} + +static void set_inh_caps(char *capstring) +{ + struct caps caps; + + getcaps(&caps); + + capstring = strtok(capstring, ","); + while (capstring) { + unsigned long cap; + + parse_cap(&cap, capstring); + if (CAP_TO_INDEX(cap) >= caps.u32s) + bb_error_msg_and_die("invalid capability cap"); + + if (capstring[0] == '+') + caps.data[CAP_TO_INDEX(cap)].inheritable |= CAP_TO_MASK(cap); + else + caps.data[CAP_TO_INDEX(cap)].inheritable &= ~CAP_TO_MASK(cap); + capstring = strtok(NULL, ","); + } + + if ((capset(&caps.header, caps.data)) < 0) + bb_perror_msg_and_die("capset"); + + if (ENABLE_FEATURE_CLEAN_UP) + free(caps.data); +} + +static void set_ambient_caps(char *string) +{ + char *cap; + + cap = strtok(string, ","); + while (cap) { + unsigned long index; + + parse_cap(&index, cap); + if (cap[0] == '+') { + if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, index, 0, 0) < 0) + bb_perror_msg("cap_ambient_raise"); + } else { + if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_LOWER, index, 0, 0) < 0) + bb_perror_msg("cap_ambient_lower"); + } + cap = strtok(NULL, ","); + } +} #endif /* FEATURE_SETPRIV_CAPABILITIES */ #if ENABLE_FEATURE_SETPRIV_DUMP @@ -317,93 +399,6 @@ static int dump(void) } #endif /* FEATURE_SETPRIV_DUMP */ -#if ENABLE_FEATURE_SETPRIV_CAPABILITIES -static void parse_cap(unsigned long *index, const char *cap) -{ - unsigned long i; - - switch (cap[0]) { - case '-': - break; - case '+': - break; - default: - bb_error_msg_and_die("invalid capability '%s'", cap); - break; - } - - cap++; - if ((sscanf(cap, "cap_%lu", &i)) == 1) { - if (!cap_valid(i)) - bb_error_msg_and_die("unsupported capability '%s'", cap); - *index = i; - return; - } - -# if ENABLE_FEATURE_SETPRIV_CAPABILITY_NAMES - for (i = 0; i < ARRAY_SIZE(capabilities); i++) { - if (strcmp(capabilities[i], cap) != 0) - continue; - - if (!cap_valid(i)) - bb_error_msg_and_die("unsupported capability '%s'", cap); - *index = i; - return; - } -# endif - - bb_error_msg_and_die("unknown capability '%s'", cap); -} - -static void set_inh_caps(char *capstring) -{ - struct caps caps; - - getcaps(&caps); - - capstring = strtok(capstring, ","); - while (capstring) { - unsigned long cap; - - parse_cap(&cap, capstring); - if (CAP_TO_INDEX(cap) >= caps.u32s) - bb_error_msg_and_die("invalid capability cap"); - - if (capstring[0] == '+') - caps.data[CAP_TO_INDEX(cap)].inheritable |= CAP_TO_MASK(cap); - else - caps.data[CAP_TO_INDEX(cap)].inheritable &= ~CAP_TO_MASK(cap); - capstring = strtok(NULL, ","); - } - - if ((capset(&caps.header, caps.data)) < 0) - bb_perror_msg_and_die("capset"); - - if (ENABLE_FEATURE_CLEAN_UP) - free(caps.data); -} - -static void set_ambient_caps(char *string) -{ - char *cap; - - cap = strtok(string, ","); - while (cap) { - unsigned long index; - - parse_cap(&index, cap); - if (cap[0] == '+') { - if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_RAISE, index, 0, 0) < 0) - bb_perror_msg("cap_ambient_raise"); - } else { - if (prctl(PR_CAP_AMBIENT, PR_CAP_AMBIENT_LOWER, index, 0, 0) < 0) - bb_perror_msg("cap_ambient_lower"); - } - cap = strtok(NULL, ","); - } -} -#endif /* FEATURE_SETPRIV_CAPABILITIES */ - int setpriv_main(int argc, char **argv) MAIN_EXTERNALLY_VISIBLE; int setpriv_main(int argc UNUSED_PARAM, char **argv) { -- 2.25.1