网上各种答案，各种不靠谱。
更新版本即可(7.45及以上都可以)。老版本对ssl3可能兼容不好。
不行的版本
cuihuan:~ cuixiaohuan$ curl --version
curl 7.37.1 (x86_64-apple-darwin14.0) libcurl/7.37.1 SecureTransport zlib/1.2.5
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtsp smtp smtps telnet tftp
Features: AsynchDNS GSS-Negotiate IPv6 Largefile NTLM NTLM_WB SSL libz更新后的版本
cuihuan:bin cuixiaohuan$ ./curl --version
curl 7.46.0 (x86_64-apple-darwin14.1.1) libcurl/7.46.0 SecureTransport zlib/1.2.5
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtsp smb smbs smtp smtps telnet tftp
Features: IPv6 Largefile NTLM NTLM_WB SSL libz UnixSockets然后用brew link一下即可
cuihuan:bin cuixiaohuan$ brew link curl --force
Linking /usr/local/Cellar/curl/7.46.0... 348 symlinks created如果无法绑定上，需要更换curl
cuihuan:bin cuixiaohuan$ pwd
/usr/bin
cuihuan:bin cuixiaohuan$ sudo rm curl
Password:
cuihuan:bin cuixiaohuan$ sudo cp /usr/local/Cellar/curl/7.46.0/bin/curl ./
cuihuan:bin cuixiaohuan$ curl --version
curl 7.46.0 (x86_64-apple-darwin14.1.1) libcurl/7.46.0 SecureTransport zlib/1.2.5
Protocols: dict file ftp ftps gopher http https imap imaps ldap ldaps pop3 pop3s rtsp smb smbs smtp smtps telnet tftp
Features: IPv6 Largefile NTLM NTLM_WB SSL libz UnixSockets