X-Git-Url: https://git.openssl.org/?p=openssl.git;a=blobdiff_plain;f=INSTALL;h=71d6b8883fb20f0d7483944a82b9ebd812b0fa5a;hp=08758339a2b5c987ba26b2f7bb8151b7e8cc135d;hb=4845aeba4c49e1bd65259a5014d7e3ab38657d42;hpb=b92013602b6666314ad200d48e10a1aaa2c5b2fa diff --git a/INSTALL b/INSTALL index 08758339a2..71d6b8883f 100644 --- a/INSTALL +++ b/INSTALL @@ -1,4 +1,3 @@ - OPENSSL INSTALLATION -------------------- @@ -22,6 +21,7 @@ * NOTES.VMS (OpenVMS) * NOTES.WIN (any supported Windows) * NOTES.DJGPP (DOS platform with DJGPP) + * NOTES.ANDROID (obviously Android [NDK]) Notational conventions in this document --------------------------------------- @@ -208,12 +208,40 @@ without a path). This flag must be provided if the zlib-dynamic option is not also used. If zlib-dynamic is used then this flag is optional and a default value ("ZLIB1") is - used if not provided. + used if not provided. On VMS: this is the filename of the zlib library (with or without a path). This flag is optional and if not provided then "GNV$LIBZSHR", "GNV$LIBZSHR32" or "GNV$LIBZSHR64" is used by default depending on the pointer size chosen. + + --with-rand-seed=seed1[,seed2,...] + A comma separated list of seeding methods which will be tried + by OpenSSL in order to obtain random input (a.k.a "entropy") + for seeding its cryptographically secure random number + generator (CSPRNG). The current seeding methods are: + + os: Use a trusted operating system entropy source. + This is the default method if such an entropy + source exists. + getrandom: Use the L system call if available. + devrandom: Use the the first device from the DEVRANDOM list + which can be opened to read random bytes. The + DEVRANDOM preprocessor constant expands to + "/dev/urandom","/dev/random","/dev/srandom" on + most unix-ish operating systems. + egd: Check for an entropy generating daemon. + rdcpu: Use the RDSEED or RDRAND command if provided by + the CPU. + librandom: Use librandom (not implemented yet). + none: Disable automatic seeding. This is the default + on some operating systems where no suitable + entropy source exists, or no support for it is + implemented yet. + + For more information, see the section 'Note on random number + generation' at the end of this document. + no-afalgeng Don't build the AFALG engine. This option will be forced if on a platform that does not support AFALG. @@ -536,7 +564,7 @@ these flags interact with those variables. VAR=value - Assignment if environment variable for Configure. These + Assignment of environment variable for Configure. These work just like normal environment variable assignments, but are supported on all platforms and are confined to the configuration scripts only. These assignments override @@ -561,12 +589,16 @@ CPPDEFINES List of CPP macro definitions, separated by a platform specific character (':' or space for Unix, ';' for Windows, ',' for - VMS). This can be used in place of -D. + VMS). This can be used instead of using + -D (or what corresponds to that on your + compiler) in CPPFLAGS. CPPINCLUDES List of CPP inclusion directories, separated the same way as for CPPDEFINES. This can - be used in place of -I. + be used instead of -I (or what corresponds + to that on your compiler) in CPPFLAGS. HASHBANGPERL Perl invocation to be inserted after '#!' - in public perl scripts. + in public perl scripts (only relevant on + Unix). LD The program linker (not used on Unix, $(CC) is used there). LDFLAGS Flags for the shared library, DSO and @@ -587,6 +619,24 @@ ./config -DFOO CPPFLAGS=-DBAR -DCOOKIE + Backward compatibility note: + + To be compatible with older configuration scripts, the + environment variables are ignored if compiling / linking + flags are given on the command line, except for these: + + AR, CC, CXX, CROSS_COMPILE, HASHBANGPERL, PERL, RANLIB, RC + and WINDRES + + For example, the following command will not see -DBAR: + + CPPFLAGS=-DBAR ./config -DCOOKIE + + However, the following will see both set variables: + + CC=gcc CROSS_COMPILE=x86_64-w64-mingw32- \ + ./config -DCOOKIE + reconf reconfigure Reconfigure from earlier data. This fetches the previous @@ -787,7 +837,7 @@ $ nmake TESTS='test_rsa test_dsa' test # Windows And of course, you can combine (Unix example shown): - + $ make VERBOSE=1 TESTS='test_rsa test_dsa' test You can find the list of available tests like this: @@ -860,7 +910,7 @@ command symbols. [.SYSTEST] Contains the installation verification procedure. [.HTML] Contains the HTML rendition of the manual pages. - + Additionally, install will add the following directories under OPENSSLDIR (the directory given with --openssldir or its default) @@ -1141,10 +1191,22 @@ Availability of cryptographically secure random numbers is required for secret key generation. OpenSSL provides several options to seed the - internal PRNG. If not properly seeded, the internal PRNG will refuse + internal CSPRNG. If not properly seeded, the internal CSPRNG will refuse to deliver random bytes and a "PRNG not seeded error" will occur. - On systems without /dev/urandom (or similar) device, it may be necessary - to install additional support software to obtain a random seed. - Please check out the manual pages for RAND_add(), RAND_bytes(), RAND_egd(), - and the FAQ for more information. + The seeding method can be configured using the --with-rand-seed option, + which can be used to specify a comma separated list of seed methods. + However in most cases OpenSSL will choose a suitable default method, + so it is not necessary to explicitely provide this option. Note also + that not all methods are available on all platforms. + + I) On operating systems which provide a suitable randomness source (in + form of a system call or system device), OpenSSL will use the optimal + available method to seed the CSPRNG from the operating system's + randomness sources. This corresponds to the option --with-rand-seed=os. + + II) On systems without such a suitable randomness source, automatic seeding + and reseeding is disabled (--with-rand-seed=none) and it may be necessary + to install additional support software to obtain a random seed and reseed + the CSPRNG manually. Please check out the manual pages for RAND_add(), + RAND_bytes(), RAND_egd(), and the FAQ for more information.