语法：
srp [args] [user]
参数说明：
-verbose Talk alot while doing things
-config file A config file
-name arg The particular srp definition to use
-srpvfile arg The srp verifier file name
-add add an user and srp verifier
-modify modify the srp verifier of an existing user
-delete delete user from verifier file
-list list user
-gn arg g and N values to be used for new verifier
-userinfo arg additional info to be set for user
-passin arg input file pass phrase source
-passout arg output file pass phrase source
-engine e - use engine e, possibly a hardware device.
-rand file:file:...
load the file (or the files in the directory) into
the random number generator
openssl系列命令大纲：http://www.cnblogs.com/aixiaoxiaoyu/p/8650180.html